Genotoxic Effects of Exposure to Gasoline Fumes on Petrol Pump Workers.

PubMed

Shaikh, Amrin; Barot, Darshana; Chandel, Divya

2018-04-01

Petrol pump workers are occupationally exposed to gasoline and its fumes consisting of several mutagenic chemicals. To evaluate the genotoxic effects of exposure to gasoline fumes on petrol pump workers. The study groups included 70 petrol pump workers (exposed group) and 70 healthy age-matched individuals with no known exposure (comparison group). Buccal micronucleus cytome assay (BMCyt) was performed to check the genotoxicity caused due to inhalation of gasoline fumes. The frequencies of micronucleated cells, nuclear bud, condensed chromatin cells, karyorrhectic cells, pyknotic cells, and karyolytic cells were significantly higher in the exposed workers compared to the comparison group. Exposure to gasoline fumes is associated with increased frequency of cell abnormalities. This may lead to various health consequences including cancer in those occupationally exposed to gasoline fumes.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pearce, T.C.; Waters, M.H.L.

Measurements have been made of the fuel consumption of a petrol and a diesel car when starting from cold. The cars were the 1.1 liter petrol VW Golf and the 1.5 liter diesel version, which have the same passenger accommodation and nearly identical road performance. It was found that the diesel car used less fuel in the warm-up period than the petrol, both when being driven at constant speed on a test track and with the engine idling and the car stationary. (Copyright (c) Crown Copyright 1980.)

British and German Logistics Support during the World War 2 North African Campaign

DTIC Science & Technology

1990-02-05

situation was now approaching disaster. The tanker, Prosperina, which we had hoped would bring some relief in the petrol situation, had been bombed...and sunk outside Tobruk. There was only enough petrol left to keep supply traffic going between Tripoli and the front for another three days, and that...had not the petrol to do It. So we were compelled to allow the armored formations In the northern part of our line to assault the British salient

Detection of adulteration in diesel and petrol by kerosene using SPR based fiber optic technique

NASA Astrophysics Data System (ADS)

Verma, Rajneesh K.; Suwalka, Payal; Yadav, Jatin

2018-07-01

In this paper we focused on the experimental investigations for fabricating a surface plasmon resonance (SPR) based fiber optic sensor for the detection of the extent of adulteration in petrochemicals: petrol and diesel by kerosene. Primarily it is observed that the refractive index of the petrol and diesel changes if we mix kerosene in it. The variation in refractive index is linear in nature. Utilizing the phenomenon of surface plasmon resonance in Krestchmann configuration on optical fiber, the percentage of adulteration in petrol and diesel is detected. The detection level of adulteration is quantified systematically for both the petrol and diesel. The study carried out here explores the possibility of utilizing SPR technique for the detection of the level of adulteration in petrochemicals. The suitability of the optical fiber for remote sensing and its immunity towards electromagnetic interaction makes this probe very useful for such endeavor. High sensitivity, easy construction and its portability, makes this study important in the development of SPR based optical fiber sensors for petrochemical industries. Apart from this various aspects of environment polluting hazardous/toxic gases as an emission product of automobile fuels has also been discussed.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jakobsson, R.; Bellander, T.; Lundberg, I.

The risk of acute myeloid leukemia (AML) within different occupations was studied, using occupational information obtained from the Swedish 1970 census. Follow-up in the Swedish Cancer Register was carried out from 1971 to 1984. Among male petrol station attendants, 10 cases were observed versus 2.8 expected (observed/expected = 3.6, 95% confidence interval 1.7--6.6). For several decades, Swedish petrol has contained 3--5% of benzene. Thus, a hypothesis was that benzene had contributed to the excess risk. The work histories of the 10 cases were reconstructed through interviews with surviving relatives and were compatible with the hypothesis. However, because the air benzenemore » exposures at petrol stations always have been lower than benzene exposures associated previously with an increased risk of AML, the leukemogenic effect of benzene may have been potentiated by other petrol or vehicle exhaust components. 23 refs., 1 fig., 1 tab.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wood, R.A.; Downing, B.R.; Pearce, T.C.

The consumption of primary energy by diesel, petrol and electric versions of a light van was compared under high-density urban traffic conditions. The vehicles were driven repeatedly round a 10km route in Central London and measurements of fuel consumption, distance travelled and time were made for each route section. Multiple regression analysis established vehicle sensitivities to variations in average speed, payload, road type, regenerated energy (electric vehicle), kinetic energy, weather and driver. The diesel vehicle used primary energy more efficiently than either the petrol or the electric vehicle over the entire speed range observed, the ratio of energy consumption (diesel:petrol:electric)more » being 100:185:198 at the average speed during the experiment (17.58km/h). The petrol vehicle was more efficient than the electric over most of the speed range, but was less efficient at speeds below about 14km/h. It is concluded that the diesel vehicle is the most efficient for urban delivery duties.« less

Characterization of biosurfactants from indigenous soil bacteria recovered from oil contaminated sites.

PubMed

Kumar, Govind; Kumar, Rajesh; Sharma, Anita

2015-09-01

Three bacterial isolates (G1, G2 and G3) characterized as Pseudomonas plecoglossicida, Lysinibacillus fusiformis and Bacillus safensis were recovered from contaminated soil of oil refinery. These bacterial isolates produced biosurfactants in MSM medium in stationary phase. Biosurfactants were characterized on the basis of their emulsifying properties with petrol, diesel, mobil oil and petrol engine oil. Reduction in surface tension (below 40 mN m(-1)) and blood hemolysis were also included in biosurfactants characterization. Emulsification indices of G1, G2 and G3 were in the range of 98.82, 23.53 and 58.82 for petrol; 29.411,1.05 and 70.588 for diesel; 35.31, 2.93 and 17.60 for mobil oil and 35.284, 58.82 and 17.647 for petrol engine oil respectively. Dry weight of the extracted biosurfactant was 4.6, 1.4 and 2.4 g I(-1) for G1, G2 and G3 respectively. Structural analysis of the biosurfactants by Fourier Transform Infrared Spectroscopy (FTIR) revealed significant differences in the bonding pattern of individual biosurfactant.

Exposure of Petrol Station Attendants and Auto Mechanics to Premium Motor Sprit Fumes in Calabar, Nigeria

PubMed Central

Udonwa, N. E.; Uko, E. K.; Ikpeme, B. M.; Ibanga, I. A.; Okon, B. O.

2009-01-01

A population-based-cross-sectional survey was carried out to investigate the potential risk of exposure to premium motor spirit (PMS) fumes in Calabar, Nigeria, among Automobile Mechanics (AM), Petrol Station Attendants (PSA) and the general population. Structured questionnaire was administered on the randomly chosen subjects to elicit information on their exposure to PMS. Duration of exposure was taken as the length of work in their various occupations. Venous blood was taken for methaemoglobin (MetHb) and packed cells volume (PCV). Mean MetHb value was higher in AM (7.3%) and PSA (5.8%) than in the subjects from the general population (2.7%). PCV was lower in PSA (30.8%), than AM (33.3%) and the subjects from the general population (40.8%). MetHb level was directly proportional, and PCV inversely related, to the duration of exposure. The study suggested increased exposure to petrol fumes among AM, PSA, and MetHb as a useful biomarker in determining the level of exposure to benzene in petrol vapour. PMID:19936128

Urban traffic pollution reduction for sedan cars using petrol engines by hydro-oxide gas inclusion.

PubMed

Al-Rousan, Ammar A; Alkheder, Sharaf; Musmar, Sa'ed A

2015-12-01

Petrol cars, in particular nonhybrid cars, contribute significantly to the pollution problem as compared with other types of cars. The originality of this article falls in the direction of using hydro-oxy gas to reduce pollution from petrol car engines. Experiments were performed in city areas at low real speeds, with constant engine speeds in the average of 2500 rpm and at variable velocity ratios (first speed was 10-20 km/hr, second speed was 20-35 km/hr, and third speed was 35-50 km/hr). Results indicated that through using hydro-oxy gas, a noticeable reduction in pollution was recorded. Oxygen (O2) percentage has increased by about 2.5%, and nitric oxide (NO) level has been reduced by about 500 ppm. Carbon monoxide (CO) has decreased by about 2.2%, and also CO2 has decreased by 2.1%. It's worth mentioning that for hybrid system in cars at speeds between 10 and 50 km/hr, the emission percentage change is zero. However, hybrid cars are less abundant than petrol cars. The originality of this paper falls in the direction of using hydro-oxy gas to reduce pollution from petrol car engines. Experiments were performed in city areas at low real speeds, with constant engine speeds in the average of 2500 rpm and at variable velocity ratios (first speed was 10-20 km/hr, second speed was 20-35 km/hr, and third speed was 35-50 km/h).

Assessing cognition following petrol sniffing for Indigenous Australians.

PubMed

Dingwall, Kylie M; Lewis, Matthew S; Maruff, Paul; Cairney, Sheree

2010-07-01

Chronic petrol inhalation can be associated with significant cognitive impairment. While rehabilitation programs can rely on such skills to educate clients and achieve treatment outcomes, cognitive function is rarely assessed on admission. This is particularly true for Indigenous populations where standard assessments are not appropriate. This paper describes a process for assessing cognition in Indigenous Australians. Two studies investigate firstly the demographic factors impacting on cognition for healthy Indigenous Australians and secondly the utility of the assessment process for detecting petrol sniffing related cognitive impairments. Study One assessed a naturalistic sample of healthy Indigenous Australians from the Northern Territory (N = 206; mean age = 28.03) on computerised tests of psychomotor speed, visual attention, memory, learning, spatial awareness and executive functions. Multiple regression analyses determined the unique contributions of six factors (age, education, gender, familiarity with computers, regular long term cannabis use and locality) to the variance in performance for this group. Study Two examined group differences in cognitive performance on the same tests between healthy Indigenous Australians (N = 96) and Indigenous petrol sniffers (N = 50; both age restricted to < 26 years) while controlling those factors found to impact on performance from Study One. Age, computer familiarity, and education significantly contributed to the variance in performance measures. While controlling these factors, petrol abuse was associated with poorer performance on complex tasks of psychomotor, visual attention, memory, learning, spatial awareness and executive function. This assessment process is useful for detecting substance abuse related impairments in Indigenous Australians and when using this assessment process, age and computer familiarity in particular should be controlled for.

Pipes, Petrol, Paint and Pewter: The Rise and Fall of Lead

ERIC Educational Resources Information Center

Peacock, Alan

2010-01-01

Lead is a good example of a metal that was used for many things over centuries--in water pipes, paints, on roofs, and in leaded petrol, for example--but was superseded as scientists discovered "new" metals, and because its toxicity became a problem. It was originally an important element in pewter utensils, alloyed with tin; it made the…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Conway, R.

This article describes a petrol (gasoline) engine development project to combine the duel technologies of an Otto cycle engine with a modified cooling system and a high-tech processor-controlled bottoming cycle to harness not only the waste heat from the exhaust gases but also a significant proportion of the heat lost by a conventional petrol engine to the water coolant, resulting in a very substantial increase in energy conversion efficiency.

Petroleum hydrocarbon pollution of urban topsoil in Ibadan city, Nigeria

DOE Office of Scientific and Technical Information (OSTI.GOV)

Onianwa, P.C.

The distribution of total petroleum hydrocarbon in topsoils from various parts of Ibadan city, Nigeria, was studied. Samples were selected from around the following zones: (a) railway tracks, (b) petrol stations, (c) refuse dumps, (d) residential areas, (e) high traffic density areas, (f) mechanical workshops, and (g) control zones. Contamination of the topsoil with hydrocarbons was significant only around petrol stations and mechanical workshops where the factors of accumulation were 10.1 and 4.72, respectively. The general trend in hydrocarbon levels was petrol station > mechanical workshop > refuse dumps > high traffic areas {ge} rail tracks > control residential areas.more » The results highlight the need to monitor urban environments that are remote from petroleum exploration activities for petroleum hydrocarbon contamination. 19 refs., 3 tabs.« less

Petrol filling workers as biomonitor of PAH exposure and functional health capacity in resource-limited settings of city Rawalpindi, Pakistan.

PubMed

Rashid, Audil; Tao, Shu; Uddin, Ikhtiar; Kamal, Atif

2017-07-01

This is the first study from Pakistan to report the exposure of petrol filling workers (n = 120) to naphthalene (Nap) and pyrene (Pyr) in relation to their functional capacities and health outcome. A group of non-exposed subjects (controls n = 46) was also recruited for comparison. The perceived health risk of the exposed workers was monitored using a questionnaire based on the self-reporting survey. The observed physical anomalies related to the health disorder included the acidity after meals, eye redness, appetite loss, skin lesions, and dryness of oral cavity, while those related to neurasthenic symptoms included the body aches, energy loss, twitching, fatigue, sleeplessness, fainting, and irritability. Mean Nap level observed in the exposed group (106 μg L -1 ) was significantly correlated (r = 0.49; p < 0.01) with cigarette smoking, while the average Pyr concentration (19.18 μg L -1 ) was associated with job duration. Workers exposed for 6 h per day or more had significantly high prevalence of physical disorders (OR = 2.79, 95% CI = 1.28-6.09). Neurasthenic symptoms were found in 65% of the subjects and were associated with years of involvement in job. Ten years or more work duration at petrol pumps could be associated with a substantial development of neurasthenic effects (OR = 2.80, 95% CI = 1.23-6.34). In conclusion, the subjects ascribed the disturbances in physical and neurological behavior to their occupation (petrol filling) and also rated their overall health and functional capacity as poor. To promote health of petrol pump workers, reduction in work hours and provision of masks and gloves could be introduced as occupational health interventions.

Antibacterial activity of Hygrophila stricta and Peperomia pellucida.

PubMed

Khan, M R; Omoloso, A D

2002-06-01

The crude methanolic extracts of Hygrophila scricta and Peperomia pellucida were fractionated into petrol, dichloromethane, ethyl acetate and butanol. All the crude extracts and the fractions exhibited a very good level of broad spectrum antibacterial activity. The fractions were more active than the crude extracts. The petrol fraction of H. stricta and the butanol fraction of P. pellucida were particularly good. No activity was noticed for the moulds tested.

Lead reduction of petrol and blood lead concentrations of athletes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maresky, L.S.; Kotze, T.J.V.W.; Grobler, S.R.

In 1984, it was determined that the blood of long-distance runners in South Africa contained unacceptably high concentrations of lead. Subsequently, the petrol lead level in South Africa was reduced from 0.8 g/l to 0.4 g/l. In view of this reduction, a follow-up investigation of its effect on the blood lead concentration of South African runners was undertaken. Blood lead samples were analyzed by graphite furnace atomic absorption spectrophotometry. The mean values of blood lead concentrations dropped from 52 to 13 {mu}g/dl and from 20 to 8.5 {mu}g/dl for the urban and rural trainers, respectively. A highly significant decrease inmore » blood lead levels was found and was mainly attributable to the reduction in the petrol lead levels. The blood lead results for rural trainers indicated that there still exists a certain degree of lead pollution in athletes from nonremote areas.« less

Measurement of 238U and 232Th in Petrol, Gas-oil and Lubricant Samples by Using Nuclear Track Detectors and Resulting Radiation Doses to the Skin of Mechanic Workers.

PubMed

Misdaq, M A; Chaouqi, A; Ouguidi, J; Touti, R; Mortassim, A

2015-10-01

Workers in repair shops of vehicles (cars, buses, truck, etc.) clean carburetors, check fuel distribution, and perform oil changes and greasing. To explore the exposure pathway of (238)U and (232)Th and its decay products to the skin of mechanic workers, these radionuclides were measured inside petrol, gas-oil, and lubricant material samples by means of CR-39 and LR-115 type II solid state nuclear track detectors (SSNTDs), and corresponding annual committed equivalent doses to skin were determined. The maximum total equivalent effective dose to skin due to the (238)U and (232)Th series from the application of different petrol, gas-oil, and lubricant samples by mechanic workers was found equal to 1.2 mSv y(-1) cm(-2).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghosh, B.B.

The object of the study reported in this paper was to investigate the possibility of using the blend of kerosene with petrol in a gasoline engines, without much losses in performance. The authors carried out experiments on a four-stroke cycle Briggs and Stratton S. I. Engine using five blends of kerosene with petrol at a compression ratios 5.3 and 7.47 to 1 with and without surge chambers, at a constant engine speed of 1500 rev/min with the following conclusions: 1. At part-load and the lower compression ratio the brake thermal efficiency is improved with percentage increase of kerosene but atmore » the higher compression ratio it is improved only upto 50% kerosene blend with petrol. 2. The knock-free maximum bhp is reduced with (a) the percentage increase of kerosene, (b) the increase of compression ratio. 3. Use of a surge chamber increase the knock-free maximum bhp, and reduces the brake thermal efficiency.« less

Remobilisation of industrial lead depositions in ash during Australian wildfires.

PubMed

Wu, Liqin; Taylor, Mark Patrick; Handley, Heather K

2017-12-01

This study examined the recycling of lead (Pb) in ash from wildfires, its source and potential contribution to environmental contamination. Ash from wildfires was collected from four Australian sites following uncontrolled fires during 2012 to 2013 close to major urban populations in Sydney (New South Wales), Hobart (Tasmania) and Adelaide (South Australia). The samples were analysed for their total Pb concentration and Pb isotopic composition to determine the sources of Pb and the extent, if any, of industrial contamination and its recycling into the ecosystem. Median ash concentrations (23mg/kg) released from a wildfire close to Australia's largest city, Sydney, exceeded the median ash Pb concentrations from wildfires from the less populated locations of Hobart, Adelaide and NSW Central Coast. Lead isotopic compositions of Duffys Forest wildfire ash demonstrate that anthropogenic inputs from legacy leaded petrol depositions were the predominant source of contamination. Despite the cessation of leaded petrol use in Australia in 2002, historic petrol Pb deposits continue to be a substantial source of contamination in ash: petrol Pb contributed 35% of the Pb in the Woy Woy ash, 73% in Duffys Forest ash, 39% in Forcett ash and 5% in Cherryville ash. The remobilisation of legacy industrial Pb depositions by wildfires in ash results in it being a persistent and problematic contaminant in contemporary environmental systems because of its known toxicity. Copyright © 2017 Elsevier B.V. All rights reserved.

Air pollution and fuel vapour induced changes in lung functions: are fuel handlers safe?

PubMed

Chawla, Anuj; Lavania, A K

2008-01-01

Automobile exhaust derived air pollutants have become a major health hazard. Coupled with the inhalation of fuel vapour, as occurs in petrol station workers, this may lead to significant impairment of lung function. Spirometric lung functions were studied in 58 petrol station workers to examine this possibility. The forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), forced expiratory flow 25%-75% (FEF25-75) and peak expiratory flow (PEF) were recorded and analysed separately for smokers and non-smokers. The workers were divided into 5 groups for analysis of data based on the number of years of work in the petrol pumps. Outdoor air analysis was also carried out. The FVC, FEV1 and PEF declined significantly with increasing years of work in petrol stations in both smokers and non-smokers. Smoking as an independent variable was found to affect the FEV1 significantly but not FVC or PEF. The FEF25-75 was found to be the most affected spirometric value with a significant reduction with increasing years of work. Smoking as such did not affect it. Oxides of nitrogen (NOx), suspended particulate matter (SPM) and particulate matter less than 10 microns (PM10) in outdoor air were higher than the national ambient air quality standards. Exposure to automobile exhaust and fuel vapour impairs lung function in a time-dependent manner. Cigarette smoking appears to accelerate the decline.

Assessment of 8-oxo-7,8-dihydro-2'-deoxyguanosine as a marker of oxidative DNA damage in gasoline filling station attendants.

PubMed

Beerappa, Ravichandran; Venugopal, Dhananjayan; Sen, Somnath; Ambikapathy, Mala; Rao, Rajmohan Hirehal Raghavendra

2013-10-01

The urinary excretion of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) was used as a biomarker of oxidative DNA damage. The urinary 8-oxodG levels in petrol filling station attendants (exposed) at various petrol bunks were estimated as well as in the unexposed (cashier) population. A total of 100 workers (79 petrol fillers and 21 cashiers) aged from 20 to 41 years participated in the study. An informed consent was taken from each participant. Information on personal habits and health was obtained through a questionnaire. After shifts, urine samples were collected analyzed for 8-oxodG using enzyme-linked immunosorbent assay (ELISA). Fifty-three percent of workers were in the 21-30 years age group. The maximum level of 8-oxodG was observed in the age group ≥ 41 years and the minimum in the age group of 31-40 years. The maximum level of 8-oxodG was observed among those workers who had ≥ 21 years of experience. The concentrations of 8-oxodG were significantly higher in petrol fillers than those in cashiers (p < 0.05). Despite the conflicting results obtained in our study it was shown that 8-oxodG is related to chemical exposure. Further research is needed embracing a bigger number of participants to highlight the correlations between the exposure and the effects.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Facchetti, S.

Many studies were dedicated to the evaluation of the impact of automotive lead on the environment and to the assessment of its absorption in the human population. They can be subdivided into two groups, those based on changes of air and blood lead concentrations and those based on changes of air and blood lead isotopic compositions. According to various authors, 50-66% of the lead added to petrol is mobilized in the atmosphere, while most of the remainder adheres to the walls of the exhaust system from which it is expelled by mechanical and thermal shocks in the forms of easilymore » sedimented particles. The fraction directly emitted by engine exhaust fumes is found in the form of fine particles, which can be transferred a long way from the emitting sources. However important the contribution of petrol lead to the total airborne lead may be, our knowledge does not permit a straightforward calculation of the percentage of petrol lead in total blood lead, which of course can also originate from other sources (e.g., industrial, natural). To evaluate this percentage in 1973, the idea of the Isotopic Lead Experiment (ILE project) was conceived to label, on a regional scale, petrol with a nonradioactive lead of an isotopic composition sufficiently different from that of background lead and sufficiently stable in time. This Account summarizes the main results obtained by the ILE project.« less

Dynamic Geochemistry of Tetraethyl Lead Dust during the 20th Century: Getting the Lead In, Out, and Translational Beyond

PubMed Central

2018-01-01

This commentary provides a brief overview of policy decisions that permitted getting tetraethyl lead (TEL) into petrol; global geochemical lead-dust deposition evidence; 1975 catalytic converter requirements; concern about habitability of cities; a personal perspective on legacy lead research that accelerated getting TEL out of petrol; and translational beyond, including New Orleans pre- vs. post-Hurricane Katrina observations about legacy lead interventions that effectively improve urban children’s health outcomes. PMID:29701636

A Guide to Interagency Support for DoD: Military Force Deployment, Civilian Noncombatant Repatriation, and Military Patient Regulation

DTIC Science & Technology

1986-10-01

organizations for facility support of bulk petrole - um products if necessary. Military construction of petroleum storage terminals is a joint responsibili...and MSC in arranging for domestic transport of petrole - um products. These two TOAs have specific responsibilities, depending on the type of vehicle...Military Liaison Office, Kuwait U.S. Liaison Office, Tunisia U.S. Mutual Defense Assistance Office U.S. Military Group U.S. Military Liaison Office U.S

Dismissive and deceptive car dealerships create barriers to electric vehicle adoption at the point of sale

NASA Astrophysics Data System (ADS)

Zarazua de Rubens, Gerardo; Noel, Lance; Sovacool, Benjamin K.

2018-06-01

As most consumers do not have pre-existing knowledge of electric vehicles (EVs), and current market conditions favour petrol and diesel vehicles, car dealership experiences may strongly influence EV purchasing decisions. Here, we show that car dealerships pose a significant barrier at the point of sale due to a perceived lack of business case viability in relation to petrol and diesel vehicles. In 126 shopping experiences at 82 car dealerships across Denmark, Finland, Iceland, Norway and Sweden, we find that dealers were dismissive of EVs, misinformed shoppers on vehicle specifications, omitted EVs from the sales conversation and strongly oriented customers towards petrol and diesel vehicle options. Dealers' technological orientation, willingness to sell and displayed knowledge of EVs were the main contributors to likely purchase intentions. These findings combined with expert interviews suggest that government and industry signalling affect sales strategies and purchasing trends. Policy and business strategies that address barriers at the point of sale are needed to accelerate EV adoption.

Observation of increases in emission from modern vehicles over time in Hong Kong using remote sensing.

PubMed

Lau, Jason; Hung, W T; Cheung, C S

2012-04-01

In this study on-road gaseous emissions of vehicles are investigated using remote sensing measurements collected over three different periods. The results show that a high percentage of gaseous pollutants were emitted from a small percentage of vehicles. Liquified Petroleum Gas (LPG) vehicles generally have higher gaseous emissions compared to other vehicles, particularly among higher-emitting vehicles. Vehicles with high vehicle specific power (VSP) tend to have lower CO and HC emissions while petrol and LPG vehicles tend to have higher NO emissions when engine load is high. It can be observed that gaseous emission factors of petrol and LPG vehicles increase greatly within 2 years of being introduced to the vehicle fleet, suggesting that engine and catalyst performance deteriorate rapidly. It can be observed that LPG vehicles have higher levels of gaseous emissions than petrol vehicles, suggesting that proper maintenance of LPG vehicles is essential in reducing gaseous emissions from vehicles. Copyright © 2011 Elsevier Ltd. All rights reserved.

Tracing changes in atmospheric sources of lead contamination using lead isotopic compositions in Australian red wine.

PubMed

Kristensen, Louise Jane; Taylor, Mark Patrick; Evans, Andrew James

2016-07-01

Air quality data detailing changes to atmospheric composition from Australia's leaded petrol consumption is spatially and temporally limited. In order to address this data gap, wine was investigated as a potential proxy for atmospheric lead conditions. Wine spanning sixty years was collected from two wine regions proximal to the South Australian capital city, Adelaide, and analysed for lead concentration and lead and strontium isotopic composition for source apportionment. Maximum wine lead concentrations (328 μg/L) occur prior to the lead-in-air monitoring in South Australia in the later 1970s. Wine lead concentrations mirror available lead-in-air measurements and show a declining trend reflecting parallel reductions in leaded petrol emissions. Lead from petrol dominated the lead in wine ((206)Pb/(207)Pb: 1.086; (208)Pb/(207)Pb: 2.360) until the introduction of unleaded petrol, which resulted in a shift in the wine lead isotopic composition closer to vineyard soil ((206)Pb/(207)Pb: 1.137; (208)Pb/(207)Pb: 2.421). Current mining activities or vinification processes appear to have no impact with recent wine samples containing less than 4 μg/L of lead. This study demonstrates wine can be used to chronicle changes in environmental lead emissions and is an effective proxy for atmospherically sourced depositions of lead in the absence of air quality data. Copyright © 2016 Elsevier Ltd. All rights reserved.

Health Risk Assessment for Inhalation Exposure to Methyl Tertiary Butyl Ether at Petrol Stations in Southern China

PubMed Central

Hu, Dalin; Yang, Jianping; Liu, Yungang; Zhang, Wenjuan; Peng, Xiaowu; Wei, Qinzhi; Yuan, Jianhui; Zhu, Zhiliang

2016-01-01

Methyl tertiary butyl ether (MTBE), a well known gasoline additive, is used in China nationwide to enhance the octane number of gasoline and reduce harmful exhaust emissions, yet  little is known regarding the potential health risk associated with occupational exposure to MTBE in petrol stations. In this study, 97 petrol station attendants (PSAs) in southern China were recruited for an assessment of the health risk associated with inhalation exposure to MTBE. The personal exposure levels of MTBE were analyzed by Head Space Solid Phase Microextraction GC/MS, and the demographic characteristics of the PSAs were investigated. Cancer and non-cancer risks were calculated with the methods recommended by the United States Environmental Protection Agency. The results showed that the exposure levels of MTBE in operating workers were much higher than among support staff (p < 0.01) and both were lower than 50 ppm (an occupational threshold limit value). The calculated cancer risks (CRs) at the investigated petrol stations was 0.170 to 0.240 per 106 for operating workers, and 0.026 to 0.049 per 106 for support staff, which are below the typical target range for risk management of 1 × 10−6 to 1 × 10−4; The hazard quotients (HQs) for all subjects were <1. In conclusion, our study indicates that the MTBE exposure of PSAs in southern China is in a low range which does not seem to be a significant health risk. PMID:26861375

Childhood leukemia and traffic air pollution in Taiwan: petrol station density as an indicator.

PubMed

Weng, Hsu-Huei; Tsai, Shang-Shyue; Chiu, Hui-Fen; Wu, Trong-Neng; Yang, Chun-Yuh

2009-01-01

To investigate the relationship between traffic air pollution exposure and development of childhood leukemia (14 yr of age or younger), a matched case-control study was conducted using childhood deaths that occurred in Taiwan from 1996 through 2006. Data on all eligible childhood leukemia deaths were obtained from the Bureau of Vital Statistics of the Taiwan Provincial Department of Health. The control group consisted of children who died from causes other than neoplasms or diseases that were not associated with respiratory complications. The controls were pair matched to the cancer cases by gender, year of birth, and year of death. Each matched control was selected randomly from the set of possible controls for each case. Data on the number of petrol stations in study municipalities were collected from the two major petroleum supply companies, Chinese Petroleum Corporation (CPC) and Formosa Petrochemical Corporation (FPCC). The petrol station density (per square kilometer) (PSD) for study municipalities was used as an indicator of a subject's exposure to benzene and other hydrocarbons present in evaporative losses of petrol or to air emissions from motor vehicles. The subjects were divided into tertiles according to PSD in their residential municipality. The results showed that there was a significant exposure-response relationship between PSD and the risk of leukemia development in young children after controlling for possible confounders. The findings of this study warrant further investigation of the role of traffic air pollution exposure in the etiology of childhood leukemia.

Lead Exposure Assessment among Pregnant Women, Newborns, and Children: Case Study from Karachi, Pakistan.

PubMed

Fatmi, Zafar; Sahito, Ambreen; Ikegami, Akihiko; Mizuno, Atsuko; Cui, Xiaoyi; Mise, Nathan; Takagi, Mai; Kobayashi, Yayoi; Kayama, Fujio

2017-04-13

Lead (Pb) in petrol has been banned in developed countries. Despite the control of Pb in petrol since 2001, high levels were reported in the blood of pregnant women and children in Pakistan. However, the identification of sources of Pb has been elusive due to its pervasiveness. In this study, we assessed the lead intake of pregnant women and one- to three-year-old children from food, water, house dust, respirable dust, and soil. In addition, we completed the fingerprinting of the Pb isotopic ratios (LIR) of petrol and secondary sources (food, house-dust, respirable dust, soil, surma (eye cosmetics)) of exposure within the blood of pregnant women, newborns, and children. Eight families, with high (~50 μg/dL), medium (~20 μg/dL), and low blood levels (~10 μg/dL), were selected from 60 families. The main sources of exposure to lead for children were food and house-dust, and those for pregnant women were soil, respirable dust, and food. LIR was determined by inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) with a two sigma uncertainty of ±0.03%. The LIR of mothers and newborns was similar. In contrast, surma , and to a larger extent petrol, exhibited a negligible contribution to both the child's and mother's blood Pb. Household wet-mopping could be effective in reducing Pb exposure. This intake assessment could be replicated for other developing countries to identify sources of lead and the burden of lead exposure in the population.

Health Risk Assessment for Inhalation Exposure to Methyl Tertiary Butyl Ether at Petrol Stations in Southern China.

PubMed

Hu, Dalin; Yang, Jianping; Liu, Yungang; Zhang, Wenjuan; Peng, Xiaowu; Wei, Qinzhi; Yuan, Jianhui; Zhu, Zhiliang

2016-02-06

Methyl tertiary butyl ether (MTBE), a well known gasoline additive, is used in China nationwide to enhance the octane number of gasoline and reduce harmful exhaust emissions, yet little is known regarding the potential health risk associated with occupational exposure to MTBE in petrol stations. In this study, 97 petrol station attendants (PSAs) in southern China were recruited for an assessment of the health risk associated with inhalation exposure to MTBE. The personal exposure levels of MTBE were analyzed by Head Space Solid Phase Microextraction GC/MS, and the demographic characteristics of the PSAs were investigated. Cancer and non-cancer risks were calculated with the methods recommended by the United States Environmental Protection Agency. The results showed that the exposure levels of MTBE in operating workers were much higher than among support staff (p < 0.01) and both were lower than 50 ppm (an occupational threshold limit value). The calculated cancer risks (CRs) at the investigated petrol stations was 0.170 to 0.240 per 10⁶ for operating workers, and 0.026 to 0.049 per 10⁶ for support staff, which are below the typical target range for risk management of 1 × 10(-6) to 1 × 10(-4); The hazard quotients (HQs) for all subjects were <1. In conclusion, our study indicates that the MTBE exposure of PSAs in southern China is in a low range which does not seem to be a significant health risk.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Magi, F.; Facchetti, S.; Garibaldi, P.

An experiment is proposed aimed at determining the role of motor traffic in the pollution of the environment by lead, in particular of air, soil, vegetation, food and the human body. The technique of determining the isotopic composition of lead, used in the right way, should enable the whole problem to be solved. It is intended to add lead with a constant isotopic composition different from that of normally occurring lead, whether natural in origin or otherwise, to petrol in at least two regions of Italy. Analyses of lead samples taken from the principal mines have shown that Australian leadmore » (Broken Hill Mine) has quite a different isotopic composition. This lead will therefore be used to prepare the antiknock additives for petrol sold in the regions in question. Adequate sampling should make it possible to determine the contribution to pollution of lead from motor vehicle exhausts. The regions chosen for the experiment are Piedmont (city and province of Cagliari)--the first because of its high traffic density and level of industrialization, the second because of its remoteness and the lead content of the soil, which may affect food. Both regions present favourable conditions for supplying petrol of the intended type. The experiment is intended to last three years; the petrol with Australian lead will be marketed for a period of 18 months. The first results of analyses of the isotopic composition of lead contained in atmospheric dust in the city of Turin and of lead from a number of blood samples are reported in the paper. (auth)« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Erel, Y.

The isotopic composition of Pb measured in soil samples was used to determine rates and mechanisms of anthropogenic Pb migration in the soil. Petrol-Pb found in soluble halogenated aerosols migrates into the soil and is retained in the soil by the stationary soil particles. Lead infiltration velocity is approximately 5 {times} 10{sup {minus}1} cm/year, and its retardation factor is estimated to be on the order of 1 {times} 10{sup 3}. The infiltration of Pb into the soil is best described by the advection-dispersion equation under the assumption that the time scale of the longitudinal dispersion is much longer than themore » time scale of advection. Therefore, the contribution of dispersion to the solution of the advection-dispersion equation is negligible. As a result, the soil profile of petrol-Pb resembles the time-dependent input function of petrol-Pb. The estimated petrol-Pb penetration velocity and the isotopic composition profile of Pb in off-road soil are used for the computation of the fraction of anthropogenic Pb in this soil. It is calculated that the fraction of anthropogenic Pb in the acid-leached soil samples and in the soil residue of this soil profile drops from 60 and 22% near the surface to 6 and 0% at a depth of 33 cm, respectively. The downward migration velocity of Pb in soils of the studied area, which are typically 50 to 100 cm deep, implies a residence time of Pb in the soil of 100 to 200 years.« less

Associations between petrol-station density and manganese and lead in the cord blood of newborns living in Taiwan.

PubMed

Lin, Ying-Ying; Guo, Yue-Liang Leon; Chen, Pau-Chung; Liu, Jyung-Hung; Wu, Hui-Chen; Hwang, Yaw-Huei

2011-02-01

Although the anti-knocking agents used in Taiwan do not contain manganese, there are relatively high concentrations of the element in diesel fuel. As such, there have been many concerns about the impact of exposure to diesel fuels on health. This study was conducted in Taiwan to investigate the relationship between the concentration of manganese in cord blood of Taiwanese newborns and the geographic density of petrol stations as a surrogate for determining manganese emissions from vehicular traffic. A total of 1526 full-term newborns without major congenital malformations were consecutively recruited from various medical facilities from May 2004 to July 2005. Questionnaires were completed by the newborns' mothers after delivery to collect information on demographic characteristics, medical history, living environment, and other factors. Cord blood samples were collected at birth and analyzed for manganese and lead using inductively coupled plasma mass spectrometry. The geographic density of petrol stations within a 10 km zone around each newborn's residence was calculated for 1343 newborns using the Arc9 Geographic Information System. The geometric means of cord blood manganese and lead concentrations were 47.0 μg/L (GSD=1.42) and 12.6 μg/L (GSD=1.76), respectively. After adjusting for potential confounding factors, including maternal age, and maternal education, the results of a multiple linear regression model indicated that the concentration of cord blood manganese increased monotonically with an increasing density of petrol stations. However, no such association was found for levels of lead in cord blood. Further smoothing spline model analysis indicated that a ten unit increment in petrol station density made cord blood manganese and lead levels change by factors of 1.0092 (95% CI: 1.0058, 1.0127) and 0.9994 (95% CI: 0.9890, 0.9998), respectively. This finding suggests that exposure to manganese-containing fuel from motor vehicles may result in elevated manganese levels in the fetus. Further research is warranted to explore the relationship between traffic-related manganese exposure and potential adverse effects on fetal development. Copyright © 2011 Elsevier Inc. All rights reserved.

Nucleation and Growth Rates of Pyroxene, Plagioclase and Fe-Ti Oxides in Basalt

NASA Astrophysics Data System (ADS)

Burkhard, D. J.

2003-12-01

Rock textures and physical and chemical properties are determined by the time-temperature path of a magma, and the nucleation and growth rates (J, G) of crystallizing mineral phases. We applied the crystal size distribution theory (CSD) to derived J and G of pyroxene, plagioclase and of Fe-Ti oxides in basalt glass during heat treatment [1,2,3,4]. The glass was sampled from active Pu`u O`o, Kilauea, Hawaii, by hammer-dipping and subsequent quenching [5]. Temperature (T) and time (t) dependent heat treatment of the glass above temperature of nucleation and growth maxima, about 930° C, allows one to derive the activation energy of J and G, EJ, EG, which are at steady state after about 100 hrs, at 180/200, 353/307, 292/343 kJ/mol (EJ/EG, for pyroxene, plagioclase and Fe-Ti oxides). On a logarithmic scale, J and G are linear with t. A comparison with growth rates of lava cooled within a lava lobe, from top to bottom [6], suggests that independent of depth, all mineral phases crystallized at T < 1000° C. According to our results of t and T dependent J and G, such rock textures should first crystallize pyroxene, and intersertal plagioclase which is, indeed, observed. Slow cooling or a hold at T > 1000° C, should result in a first crystallization of plagioclase. This is reported in the literature [e.g., 7]. In agreement with this, we detected anorthite nuclei in the glass with HRTEM [8]. [1] Randolph R.D., Larson M.A (1979); Theory of particulate processes. Academic Press, New York. [2] Marsh B.D. (1988); Contrib.Mineral. Petrol. 99, 277-291. [3] Cashman K.V., Marsh (1988) Contrib. Mineral. Petrol. 99, 292-305. [4] Burkhard D.J.M. (2002); Contrib. Mineral. Petrol. 142, 724-527. [5] Burkhard D.J.M. (2001); J. Petrol. 42, 507-527. [6] Burkhard D.J.M. (2003; Bull. Volcanol. 65, 136-143. [7] Lofgren G.E 1983; J. Petrol., 24, 229-225. [8] Burkhard D.J.M., Wirth, R. (2001); EOS Trans. AGU, 82 (47), Fall Meet. Suppl., abstract V51B-1014.

Traffic air pollution and risk of death from bladder cancer in Taiwan using petrol station density as a pollutant indicator.

PubMed

Ho, Chi-Kung; Peng, Chiung-Yu; Yang, Chun-Yuh

2010-01-01

To investigate the relationship between air pollution and risk of death from bladder cancer, a matched cancer case-control study was conducted using deaths that occurred in Taiwan from 1997 through 2006. Data for all eligible bladder cancer deaths were obtained from the Bureau of Vital Statistics of the Taiwan Provincial Department of Health. The control group consisted of individuals who died from causes other than cancer or diseases associated with genitourinary problems. The controls were pair matched to the cases by gender, year of birth, and year of death. Each matched control was selected randomly from the set of possible controls for each case. Data for the number of petrol stations in study municipalities were collected from the two major petroleum supply companies, Chinese Petroleum Corporation (CPC) and Formosa Petrochemical Corporation (FPCC). The petrol station density (per square kilometer) (PSD) for study municipalities was used as an indicator of a subject's exposure to benzene and other hydrocarbons present in ambient evaporative losses of petrol or to air emissions from motor vehicles. The subjects were divided into tertiles according to PSD in their residential municipality. The present study showed that individuals who resided in municipalities with high PSD levels were at an increased risk of death from bladder cancer compared to subjects living in municipalities with a low PSD level; however, the differences are not statistically significant. The findings of this study warrant further investigation of the role of vehicular air pollutant emissions in the etiology of bladder cancer development.

Lead Exposure Assessment among Pregnant Women, Newborns, and Children: Case Study from Karachi, Pakistan

PubMed Central

Fatmi, Zafar; Sahito, Ambreen; Ikegami, Akihiko; Mizuno, Atsuko; Cui, Xiaoyi; Mise, Nathan; Takagi, Mai; Kobayashi, Yayoi; Kayama, Fujio

2017-01-01

Lead (Pb) in petrol has been banned in developed countries. Despite the control of Pb in petrol since 2001, high levels were reported in the blood of pregnant women and children in Pakistan. However, the identification of sources of Pb has been elusive due to its pervasiveness. In this study, we assessed the lead intake of pregnant women and one- to three-year-old children from food, water, house dust, respirable dust, and soil. In addition, we completed the fingerprinting of the Pb isotopic ratios (LIR) of petrol and secondary sources (food, house-dust, respirable dust, soil, surma (eye cosmetics)) of exposure within the blood of pregnant women, newborns, and children. Eight families, with high (~50 μg/dL), medium (~20 μg/dL), and low blood levels (~10 μg/dL), were selected from 60 families. The main sources of exposure to lead for children were food and house-dust, and those for pregnant women were soil, respirable dust, and food. LIR was determined by inductively coupled plasma quadrupole mass spectrometry (ICP-QMS) with a two sigma uncertainty of ±0.03%. The LIR of mothers and newborns was similar. In contrast, surma, and to a larger extent petrol, exhibited a negligible contribution to both the child’s and mother’s blood Pb. Household wet-mopping could be effective in reducing Pb exposure. This intake assessment could be replicated for other developing countries to identify sources of lead and the burden of lead exposure in the population. PMID:28406467

Radon and Thoron Measured in Petrol and Gas-oil Exhaust Fumes by Using CR-39 and LR-115 II Nuclear Track Detectors: Radiation Doses to the Respiratory Tract of Mechanic Workers.

PubMed

Misdaq, M A; Chaouqi, A; Ouguidi, J; Touti, R; Mortassim, A

2015-06-01

Mechanic workers are exposed to exhaust fumes when controlling vehicle engines in motion inside repair shops. To assess radiation doses due to radon short-lived progeny from the inhalation of exhaust fumes by mechanic workers, concentrations of these radionuclides were measured in petrol (gasoline) and gas-oil exhaust fumes by evaluating mean critical angles of etching of the CR-39 and LR-115 type II SSNTDs for alpha particles emitted by the radon and thoron decay series. Committed effective doses due to ²¹⁸Po and ²¹⁴Po short-lived radon decay products from the inhalation of petrol and gas-oil exhaust fumes by workers were evaluated. A maximum value of 1.35 mSv y⁻¹ due to radon short-lived decay products from the inhalation of gas-oil exhaust fumes by mechanic workers was found, which is lower than the (3-10 mSv y⁻¹) dose limit interval for workers.

Numerical investigation of VOC levels in the area of petrol stations.

PubMed

Kountouriotis, A; Aleiferis, P G; Charalambides, A G

2014-02-01

In the area of petrol stations several Volatile Organic Compounds (VOCs) leak into the atmosphere due to the evaporation of liquid fuels, especially of gasoline that is predominantly composed of light hydrocarbons. The aim of the present study is to investigate the spatial distribution of various VOCs when leaked into the atmosphere in the area of a petrol station. The study is based on numerical simulations. The effect of wind speed and direction, as well as of air temperature has been studied. Gasoline components of different properties have been studied (e.g. pentane, iso-octane, o-xylene, toluene, benzene), as well as ethanol that is considered a new fuel blend component that can be found in different fractions in new gasoline blends worldwide. The area of flammable cloud near the source of the leak is investigated for various atmospheric conditions taking into account the lower and higher flammable limits of each compound. Lastly, the exposure to gasoline vapour is studied taking into consideration the recommended occupational exposure limits of various organisations. © 2013 Elsevier B.V. All rights reserved.

Relative effects of climate and source strength on atmospheric lead concentrations in Auckland, New Zealand

NASA Astrophysics Data System (ADS)

Power, H. C.; de Freitas, C. R.; Hay, J. E.

1992-06-01

Atmospheric lead levels were examined to assess the consequences of the 46 percent reduction in the lead content of premium grade petrol in New Zealand. Since this change was implemented in July 1986 observed levels of atmospheric lead decreased by 38 percent, but all or part of this reduction may have been due to factors other than fluctuations in lead emissions, notably variations in climate. Analysis of detailed atmospheric lead, meteorological and traffic data measured contemporaneously provided insight into the atmospheric processes influencing lead levels in Auckland and formed the basis of a statistical model capable of predicting monthly lead concentrations. The model was used to predict lead levels in Auckland for the period July 1986 through to July 1989 in the absence of any reduction in the lead content of petrol. Comparison with values observed for the same period showed that all of the reduction in atmospheric lead levels since July 1986 can be attributed to the reduction in the lead content of petrol. Policy planning implications of such a finding are considered.

Oxygen fugacity control in piston-cylinder experiments: a re-evaluation

NASA Astrophysics Data System (ADS)

Jakobsson, Sigurdur; Blundy, Jon; Moore, Gordon

2014-06-01

Jakobsson (Contrib Miner Petrol 164(3):397-407, 2012) investigated a double capsule assembly for use in piston-cylinder experiments that would allow hydrous, high-temperature, and high-pressure experiments to be conducted under controlled oxygen fugacity conditions. Using a platinum outer capsule containing a metal oxide oxygen buffer (Ni-NiO or Co-CoO) and H2O, with an inner gold-palladium capsule containing hydrous melt, this study was able to compare the oxygen fugacity imposed by the outer capsule oxygen buffer with an oxygen fugacity estimated by the AuPdFe ternary system calibrated by Barr and Grove (Contrib Miner Petrol 160(5):631-643, 2010). H2O loss or gain, as well as iron loss to the capsule walls and carbon contamination, is often observed in piston-cylinder experiments and often go unexplained. Only a few have attempted to actually quantify various aspects of these changes (Brooker et al. in Am Miner 83(9-10):985-994, 1998; Truckenbrodt and Johannes in Am Miner 84:1333-1335, 1999). It was one of the goals of Jakobsson (Contrib Miner Petrol 164(3):397-407, 2012) to address these issues by using and testing the AuPdFe solution model of Barr and Grove (Contrib Miner Petrol 160(5):631-643, 2010), as well as to constrain the oxygen fugacity of the inner capsule. The oxygen fugacities of the analyzed melts were assumed to be equal to those of the solid Ni-NiO and Co-CoO buffers, which is incorrect since the melts are all undersaturated in H2O and the oxygen fugacities should therefore be lower than that of the buffer by 2 log.

Environmental assessment of food waste valorization in producing biogas for various types of energy use based on LCA approach.

PubMed

Woon, Kok Sin; Lo, Irene M C; Chiu, Sam L H; Yan, Dickson Y S

2016-04-01

This paper aims to evaluate the environmental impacts of valorizing food waste for three types of energy use, namely electricity and heat, city gas, and biogas fuel as a petrol, diesel, and liquefied petroleum gas substitute for vehicle use, with reference to the Hong Kong scenario. The life cycle based environmental assessment is conducted from bin-to-cradle system boundary via SimaPro 7.2.4 with ReCiPe 1.04. All of the inventory data of included processes is based on reports of government and industrial sectors. The results show that biogas fuel as a petrol substitute for vehicle use is advantageous over other types of energy use in regard to human health and ecosystems, and it is also the best considering the government's future emission reduction targets set out for the power and transport sectors in Hong Kong. By turning 1080 tonnes per day of food waste into biogas vehicle fuel as petrol substitute, it reduces 1.9% of greenhouse gas emissions in the transport sectors, which results a larger decrease of GHG emissions than the achieved mitigation in Hong Kong from 2005 to 2010. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of land use activities on PAH contamination in urban soils of Rawalpindi and Islamabad, Pakistan.

PubMed

Ud Din, Ikhtiar; Rashid, Audil; Mahmood, Tariq; Khalid, Azeem

2013-10-01

Urbanization can increase the vulnerability of soils to various types of contamination. Increased contamination of urban soils with polycyclic aromatic hydrocarbon (PAH) could relate to increased number of petrol pump stations and mechanical workshops-a phenomenon that needs to be constantly monitored. This study was undertaken to explore the soil PAH levels in Rawalpindi and Islamabad urban areas in relation to land use activities. Composite soil samples from petrol pump stations and mechanical workshops (n = 32) areas were evaluated for five PAHs--naphthalene, phenanthrene, pyrene, benzo[a]pyrene, and indeno(1,2,3-cd)pyrene-and compared with control area locations with minimum petroleum-related activity (n = 16). Surface samples up to 3 cm depth were collected and extraction of analytes was carried out using n-hexane and dichloromethane. Prior to running the samples, standards (100 μg ml(-1)) were run on HPLC to optimize signal to noise ratio using acetonitrile as mobile phase at a flow rate of 1.25 ml/min at 40 °C. Significant differences between petrol pump stations and mechanical workshop areas were observed for individual PAH as well as with control area soil samples. Naphthalene was found to be the most abundant PAH in soil, ranging from 2.47 to 24.36 mg kg(-1). Correlation between the benzo[a]pyrene (BaP) level in soil and the total PAH concentration (r = 0.82, P < 0.0001) revealed that BaP can be used as a potential marker for PAH pollution. A clear segregation between petrogenic and pyrogenic sources of contamination was observed when low molecular weight PAHs detected in soil was plotted against high molecular weight PAHs. The former source comprised lubricants and used engine oil found at mechanical workshops, whereas the latter could be mostly attributed to vehicular emission at petrol pumps. The results indicate that PAH contamination in urban areas of Rawalpindi and Islamabad has direct relevance with land use for petroleum activity. We conclude that in order to reduce the soil PAH exposure in urban environment, petrol pumps and mechanical workshops must be shifted to less densely populated areas because of their role as important point sources for PAH emission.

Elements and polycyclic aromatic hydrocarbons in exhaust particles emitted by light-duty vehicles.

PubMed

Alves, Célia A; Barbosa, Cátia; Rocha, Sónia; Calvo, Ana; Nunes, Teresa; Cerqueira, Mário; Pio, Casimiro; Karanasiou, Angeliki; Querol, Xavier

2015-08-01

The main purpose of this work was to evaluate the chemical composition of particulate matter (PM) emitted by eight different light-duty vehicles. Exhaust samples from petrol and diesel cars (Euro 3 to Euro 5) were collected in a chassis dynamometer facility. To simulate the real-world driving conditions, three ARTEMIS cycles were followed: road, to simulate a fluid traffic flow and urban with hot and cold starts, to simulate driving conditions in cities. Samples were analysed for the water-soluble ions, for the elemental composition and for polycyclic aromatic hydrocarbons (PAHs), respectively, by ion chromatography, inductively coupled plasma atomic emission spectroscopy (ICP-AES), inductively coupled plasma mass spectrometry (ICP-MS) and gas chromatography-mass spectrometry (GC-MS). Nitrate and phosphate were the major water-soluble ions in the exhaust particles emitted from diesel and petrol vehicles, respectively. The amount of material emitted is affected by the vehicle age. For vehicles ≥Euro 4, most elements were below the detection limits. Sodium, with emission factors in the ranges 23.5-62.4 and 78.2-227μg km(-1), for petrol and diesel Euro 3 vehicles, respectively, was the major element. The emission factors of metallic elements indicated that diesel vehicles release three to five times more than petrol automobiles. Element emissions under urban cycles are higher than those found for on-road driving, being three or four times higher, for petrol vehicles, and two or three times, for diesel vehicles. The difference between cycles is mainly due to the high emissions for the urban cycle with hot start-up. As registered for elements, most of the PAH emissions for vehicles ≥Euro 4 were also below the detection limits. Regardless of the vehicle models or driving cycles, the two- to four-ring PAHs were always dominant. Naphthalene, with emission factors up to 925 μg km(-1), was always the most abundant PAH. The relative cancer risk associated with naphthalene was estimated to be up to several orders of magnitude higher than any of the chemical species found in the PM phase. The highest PAH emission factors were registered for diesel-powered vehicles. The condition of the vehicle can exert a decisive influence on both element and PAH emissions.

Exposure to BTEX and Ethers in Petrol Station Attendants and Proposal of Biological Exposure Equivalents for Urinary Benzene and MTBE.

PubMed

Campo, Laura; Rossella, Federica; Mercadante, Rosa; Fustinoni, Silvia

2016-04-01

To assess exposure to benzene (BEN) and other aromatic compounds (toluene, ethylbenzene, m+p-xylene, o-xylene) (BTEX), methyl tert-butyl ether (MTBE), and ethyl tert-butyl ether (ETBE) in petrol station workers using air sampling and biological monitoring and to propose biological equivalents to occupational limit values. Eighty-nine petrol station workers and 90 control subjects were investigated. Personal exposure to airborne BTEX and ethers was assessed during a mid-week shift; urine samples were collected at the beginning of the work week, prior to and at the end of air sampling. Petrol station workers had median airborne exposures to benzene and MTBE of 59 and 408 µg m(-3), respectively, with urinary benzene (BEN-U) and MTBE (MTBE-U) of 339 and 780 ng l(-1), respectively. Concentrations in petrol station workers were higher than in control subjects. There were significant positive correlations between airborne exposure and the corresponding biological marker, with Pearson's correlation coefficient (r) values of 0.437 and 0.865 for benzene and MTBE, respectively. There was also a strong correlation between airborne benzene and urinary MTBE (r = 0.835). Multiple linear regression analysis showed that the urinary levels of benzene were influenced by personal airborne exposure, urinary creatinine, and tobacco smoking [determination coefficient (R(2)) 0.572], while MTBE-U was influenced only by personal exposure (R(2) = 0.741). BEN-U and MTBE-U are sensitive and specific biomarkers of low occupational exposures. We propose using BEN-U as biomarker of exposure to benzene in nonsmokers and suggest 1457 ng l(-1) in end shift urine samples as biological exposure equivalent to the EU occupational limit value of 1 p.p.m.; for both smokers and nonsmokers, MTBE-U may be proposed as a surrogate biomarker of benzene exposure, with a biological exposure equivalent of 22 µg l(-1) in end shift samples. For MTBE exposure, we suggest the use of MTBE-U with a biological exposure equivalent of 22 µg l(-1) corresponding to the occupational limit value of 50 p.p.m. © The Author 2015. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frederick, P.R.

The purpose of this research was to provide a handbook on Project PETROL RAM and its ideas for enhancing the base-level fuels operations. This handbook is to serve as an introduction and reference guide to the components, characteristics, and capabilities of the proposed initiative. In preparing this handbook, available information on the structure, operations, and procedures of a typical base Fuels Management Branch was gathered, then condensed and simplified. For added depth and understanding, personal interviews with personnel involved in the design and development of this project were conducted. The research resulted in a handbook that describes, in simplified terminology,more » the different systems which are being developed under the Project PETROL RAM initiative.« less

Adolescent inhalant abuse leads to other drug use and impaired growth; implications for diagnosis.

PubMed

Crossin, Rose; Cairney, Sheree; Lawrence, Andrew J; Duncan, Jhodie R

2017-02-01

Abuse of inhalants containing the volatile solvent toluene is a significant public health issue, especially for adolescent and Indigenous communities. Adolescent inhalant abuse can lead to chronic health issues and may initiate a trajectory towards further drug use. Identification of at-risk individuals is difficult and diagnostic tools are limited primarily to measurement of serum toluene. Our objective was to identify the effects of adolescent inhalant abuse on subsequent drug use and growth parameters, and to test the predictive power of growth parameters as a diagnostic measure for inhalant abuse. We retrospectively analysed drug use and growth data from 118 Indigenous males; 86 chronically sniffed petrol as adolescents. Petrol sniffing was the earliest drug used (mean 13 years) and increased the likelihood and earlier use of other drugs. Petrol sniffing significantly impaired height and weight and was associated with meeting 'failure to thrive' criteria; growth diagnostically out-performed serum toluene. Adolescent inhalant abuse increases the risk for subsequent and earlier drug use. It also impairs growth such that individuals meet 'failure to thrive' criteria, representing an improved diagnostic model for inhalant abuse. Implications for Public Health: Improved diagnosis of adolescent inhalant abuse may lead to earlier detection and enhanced health outcomes. © 2016 The Authors.

Brain cancer associated with environmental lead exposure: evidence from implementation of a National Petrol-Lead Phase-Out Program (PLPOP) in Taiwan between 1979 and 2007.

PubMed

Wu, Wei-Te; Lin, Yu-Jen; Liou, Saou-Hsing; Yang, Chun-Yuh; Cheng, Kuang-Fu; Tsai, Perng-Jy; Wu, Trong-Neng

2012-04-01

In 1981, a Petrol-Lead Phase-Out Program (PLPOP) was launched in Taiwan for the abatement of environmental lead emissions. The present study was intended to examine whether the high Petrol-Lead Emission Areas (PLEA) would result in an increase in the incidence rate of brain cancer based on a national data bank. The national brain cancer incidence data was obtained from the Taiwan National Cancer Registry. Age standardized incidence rates were calculated based on the 2000 WHO world standard population, and gasoline consumption data was obtained from the Bureau of Energy. The differences in the trend tests for age-standardized incidence rates of brain cancer between high, median, low, and small PLEA were analyzed. A significant increase was found from small to high PLEA in age-standardized incidence rates of brain cancer. By taking six possible confounders into account, the age-standardized incidence rates for brain cancer were highly correlated with the median and high PLEA by reference to the small PLEA. After being adjusted for a number of relevant confounders, it could be concluded that high PLEA might result in an increase in the incidence rate of brain cancer resulting from high lead exposures. Copyright © 2011 Elsevier Ltd. All rights reserved.

Haematopoietic cancer mortality among vehicle mechanics.

PubMed Central

Hunting, K L; Longbottom, H; Kalavar, S S; Stern, F; Schwartz, E; Welch, L S

1995-01-01

OBJECTIVE AND METHODS--This historical cohort study investigated causes of death among car and mobile equipment mechanics in the District of Columbia's Department of Public Works. Men who were employed for at least one year between 1977 and 1989 were eligible for inclusion in the cohort; follow up was up to the end of 1991. Three cases of leukaemia (index cases) had been reported among these workers before the inception of this study. This research was undertaken to estimate the relative risk of haematological cancer among mechanics working for the District of Columbia. RESULTS--Among the 335 male fleet maintenance workers, the all cause standardised mortality ratio (SMR) was 0.50 (33 observed deaths, 95% confidence interval (95% CI) 0.35-0.70), and the all cancer SMR was 0.55 (nine deaths, 95% CI 0.25-1.05). Three deaths from lymphatic and haematopoietic cancer were observed; the SMR was 3.63 (95% CI 0.75-10.63). In the subgroup with highest potential for exposure to fuels and solvents, the SMR for leukaemia and aleukaemia was 9.26 (two deaths, 95% CI 1.12-33.43), and the SMR for other lymphatic and haematopoietic neoplasms was 2.57 (one death from malignant lymphoma, 95% CI 0.06-14.27). All three lymphatic and haematopoietic cancer deaths were among car and mobile equipment mechanics (one was an index case). The two additional index cases were a fourth mechanic who died of leukaemia in 1992, after mortality follow up ended, and a fifth mechanic who was diagnosed with leukaemia in 1988 and is still alive. CONCLUSION--Many garage mechanics in this cohort regularly used petrol to clean parts and to wash their hands; some workers would occasionally siphon petrol by mouth. Benzene, a recognised cause of haematological cancer, is a component of petrol. Previous research indicates that garage mechanics may be at risk of leukaemia and other haematological cancers, presumably due to exposure to petrol; this study supports those findings. PMID:7489058

Haematopoietic cancer mortality among vehicle mechanics.

PubMed

Hunting, K L; Longbottom, H; Kalavar, S S; Stern, F; Schwartz, E; Welch, L S

1995-10-01

This historical cohort study investigated causes of death among car and mobile equipment mechanics in the District of Columbia's Department of Public Works. Men who were employed for at least one year between 1977 and 1989 were eligible for inclusion in the cohort; follow up was up to the end of 1991. Three cases of leukaemia (index cases) had been reported among these workers before the inception of this study. This research was undertaken to estimate the relative risk of haematological cancer among mechanics working for the District of Columbia. Among the 335 male fleet maintenance workers, the all cause standardised mortality ratio (SMR) was 0.50 (33 observed deaths, 95% confidence interval (95% CI) 0.35-0.70), and the all cancer SMR was 0.55 (nine deaths, 95% CI 0.25-1.05). Three deaths from lymphatic and haematopoietic cancer were observed; the SMR was 3.63 (95% CI 0.75-10.63). In the subgroup with highest potential for exposure to fuels and solvents, the SMR for leukaemia and aleukaemia was 9.26 (two deaths, 95% CI 1.12-33.43), and the SMR for other lymphatic and haematopoietic neoplasms was 2.57 (one death from malignant lymphoma, 95% CI 0.06-14.27). All three lymphatic and haematopoietic cancer deaths were among car and mobile equipment mechanics (one was an index case). The two additional index cases were a fourth mechanic who died of leukaemia in 1992, after mortality follow up ended, and a fifth mechanic who was diagnosed with leukaemia in 1988 and is still alive. Many garage mechanics in this cohort regularly used petrol to clean parts and to wash their hands; some workers would occasionally siphon petrol by mouth. Benzene, a recognised cause of haematological cancer, is a component of petrol. Previous research indicates that garage mechanics may be at risk of leukaemia and other haematological cancers, presumably due to exposure to petrol; this study supports those findings.

An update of the Pb isotope inventory in post leaded-petrol Singapore environments.

PubMed

Carrasco, Gonzalo; Chen, Mengli; Boyle, Edward A; Tanzil, Jani; Zhou, Kuanbo; Goodkin, Nathalie F

2018-02-01

Pb is a trace metal that tracks anthropogenic pollution in natural environments. Despite recent leaded petrol phase out around Southeast Asia, the region's growth has resulted in continued exposure of Pb from a variety of sources. In this study, sources of Pb into Singapore, a highly urbanised city-state situated in the central axis of Southeast Asia, are investigated using isotopic ratios and concentrations. We compiled data from our previous analyses of aerosols, incineration fly ash and sediments, with new data from analyses of soil from gas stations, water from runoff and round-island coastal seawater to obtain a spatio-temporal overview of sources of Pb into the Singapore environment. Using 206 Pb/ 207 Pb ratio, we identified three main Pb source origins: natural Pb (1.215 ± 0.001), historic/remnant leaded petrol (1.123 ± 0.013), and present-day industrial and incinerated waste (1.148 ± 0.005). Deep reservoir sediments bore larger traces of Pb from leaded petrol, but present-day runoff waters and coastal seawater were a mix of industrial and natural sources with somewhat variable concentrations. We found temporal variability in Pb isotopic ratio in aerosols indicating alternating transboundary Pb sources to Singapore that correspond to seasonal changes in monsoon winds. By contrast, seasonal monsoon circulation did not significantly influence isotopic ratios of coastal seawater Pb. Instead, seawater Pb was driven more by location differences, suggesting stronger local-scale drivers of Pb such as point sources, water flushing, and isotope exchange. The combination of multiple historic and current sources of Pb shown in this study highlights the need for continued monitoring of Pb in Southeast Asia, especially in light of emerging industries and potential large sources of Pb such as coal combustion. Copyright © 2017 Elsevier Ltd. All rights reserved.

Work-exposure to PM10 and aromatic volatile organic compounds, excretion of urinary biomarkers and effect on the pulmonary function and heme-metabolism: A study of petrol pump workers and traffic police personnel in Kolkata City, India.

PubMed

Mukherjee, Ashit K; Chattopadhyay, Bhaskar P; Roy, Sanjit K; Das, Surojit; Mazumdar, Dipanjali; Roy, Moumita; Chakraborty, Rajarshi; Yadav, Anupa

2016-01-28

This study focused work-exposure to particulate matter ≤ 10 µm (PM 10 ), volatile organic compounds (VOCs) and biological monitoring of major VOCs (BTEX) to observe the significant effects of traffic related pollutants on respiratory and hematological systems of workers engaged in two occupational settings, petrol pumps and traffic areas of Kolkata metropolitan city, India. PM 10 was assessed by personal sampling and particle size distribution by 8-stage Cascade Impactor. VOCs were analysed by gas chromatography-flame ionization detector (GC-FID) and five urinary metabolites, trans trans- mercapturic acid (tt-MA), S-phenyl mercapturic acid (SPMA), hippuric acid (HA), mandelic acid (MA) and methyl hippuric acid (MHA) of VOCs, benzene, toluene, ethyl benzene and xylenes (BTEX) by reverse phase high performance liquid chromatography (HPLC). Pulmonary functions test (PFT) was measured Spirometrically. ∂-aminoleavulinic acid (ALA) and porphobilinogen (PBG) in lymphocytes were measured spectrophometrically following column chromatographic separation. High exposure to PM 10 , having 50% of particles, ≤ 5.0 µm in both the occupational settings. Exposure to toluene was highest in petrol pumps whereas benzene was highest (104.6 ± 99.0 μg m -3 ) for traffic police personnel. Workplace Benzene is found many fold higher than the National ambient standard. Air-benzene is correlated significantly with pre- and post-shift tt-MA (p < 0.001) and SPMA (p < 0.001) of exposed workers. Blood cell counts indicated benzene induced hematotoxicity. ALA and PBG accumulation in lymphocytes indicated alteration in heme-metabolism, especially among traffic police. Significant reduction of force exploratory volume in one second (FEV 1 ) and forced vital capacity (FVC) of fuel fillers are observed with increased tt-MA and SPMA. Study revealed PFT impairments 11.11% (6.66% restrictive and 2.22% obstructive and combined restrictive and obstructive type, each) among petrol pumps and 8.3% obstructive type among traffic police.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bates, G.J.; Germano, S.

Tests were undertaken with a Renault Express 1.4 litre converted to natural gas operation. The effect of cold starts at cold temperatures and vehicle weight on tail pipe emissions were investigated with petrol and natural gas operation over the FTP75 and the 91/441/EEC drive cycles. The results show that the emissions with natural gas are unaffected by cold temperature, unlike petrol emissions which are several times higher at -15{degree}-C than at 25{degree}-C. A crude simulation, accounting for the actual temperature, shows that the conversion of a significant quantity of light duty vehicles to natural gas operation could reduce the emissionsmore » of CO and HC by more than 90% in Switzerland. 15 refs., 17 figs., 8 tabs.« less

Ignition study of a petrol/CNG single cylinder engine

NASA Astrophysics Data System (ADS)

Khan, N.; Saleem, Z.; Mirza, A. A.

2005-11-01

Benefits of laser ignition over the electrical ignition system for Compressed Natural Gas (CNG) engines have fuelled automobile industry and led to an extensive research on basic characteristics to switch over to the emerging technologies. This study was undertaken to determine the electrical and physical characteristics of the electric spark ignition of single cylinder petrol/CNG engine to determine minimum ignition requirements and timeline of ignition events to use in subsequent laser ignition study. This communication briefly reviews the ongoing research activities and reports the results of this experimental study. The premixed petrol and CNG mixtures were tested for variation of current and voltage characteristics of the spark with speed of engine. The current magnitude of discharge circuit was found to vary linearly over a wide range of speed but the stroke to stroke fire time was found to vary nonlinearly. The DC voltage profiles were observed to fluctuate randomly during ignition process and staying constant in rest of the combustion cycle. Fire to fire peaks of current amplitudes fluctuated up to 10% of the peak values at constant speed but increased almost linearly with increase in speed. Technical barriers of laser ignition related to threshold minimum ignition energy, inter-pulse durations and firing sequence are discussed. Present findings provide a basic initiative and background information for designing suitable timeline algorithms for laser ignited leaner direct injected CNG engines.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Startsev, Aleksandr V; Stoilov, Yurii Yu

It is found that narrow non-diverging laser tracks, earlier studied in free soap films, can also arise in thin rainbow films, e.g., of petrol, on water. (laser applications and other topics in quantum electronics)

TitaniQ recrystallized: experimental confirmation of the original Ti-in-quartz calibrations

NASA Astrophysics Data System (ADS)

Thomas, Jay B.; Watson, E. Bruce; Spear, Frank S.; Wark, D. A.

2015-03-01

Several studies have reported the P- T dependencies of Ti-in-quartz solubility, and there is close agreement among three of the four experimental calibrations. New experiments were conducted in the present study to identify potential experimental disequilibrium, and to determine which Ti-in-quartz solubility calibration is most accurate. Crystals of quartz, rutile and zircon were grown from SiO2-, TiO2-, and ZrSiO4-saturated aqueous fluids in an initial synthesis experiment at 925 °C and 10 kbar in a piston-cylinder apparatus. A range of quartz crystal sizes was produced in this experiment; both large and small examples were analyzed by electron microprobe to determine whether Ti concentrations are correlated with crystal size. Cathodoluminescence images and EPMA measurements show that intercrystalline and intracrystalline variations in Ti concentrations are remarkably small regardless of crystal size. The average Ti-in-quartz concentration from the synthesis experiment is 392 ± 1 ppmw Ti, which is within 95 % confidence interval of data from the 10 kbar isobar of Wark and Watson (Contrib Mineral Petrol 152:743-754, 2006) and Thomas et al. (Contrib Mineral Petrol 160:743-759, 2010). As a cross-check on the Ti-in-quartz calibration, we also measured the concentration of Zr in rutile from the synthesis experiment. The average Zr-in-rutile concentration is 4337 ± 32 ppmw Zr, which is also within the 95 % confidence interval of the Zr-in-rutile solubility calibration of Ferry and Watson (Contrib Mineral Petrol 154:429-437, 2007). The P- T dependencies of Ti solubility in quartz and Zr solubility in rutile were applied as a thermobarometer to the experimental sample. The average Ti-in-quartz isopleth calculated from the calibration of Thomas et al. (Contrib Mineral Petrol 160:743-759, 2010) and the average Zr-in-rutile isopleth calculated from the calibration of Tomkins et al. (J Metamorph Geol 25:703-713, 2007) cross at 9.5 kbar and 920 °C, which is in excellent agreement with the P- T conditions of the synthesis experiment. Separates of the high-Ti quartz from the initial synthesis experiment described above were used as starting material in subsequent experiments at 20 kbar, at which pressure the solubility of Ti in quartz is expected to be significantly lower in the recrystallized quartz. These recrystallization experiments were conducted under wet and dry conditions at 925 °C, and under wet conditions at 850 °C. Both wet and dry recrystallization experiments produced polycrystalline quartzites. Rutile occurs as inclusions in quartz, and as individual crystals dispersed along quartz grain boundaries. Quartz that grew during the recrystallization experiments has dark cathodoluminescence indicating substantially lower Ti concentrations. The average Ti concentrations in quartz from the recrystallization experiments are within the 95 % confidence interval of a linear fit to the 20 kbar data of Thomas et al. (Contrib Mineral Petrol 160:743-759, 2010). Collectively, the results from the synthesis and recrystallization experiments confirm that the Ti-in-quartz concentrations used to calibrate the P- T dependencies of Ti-in-quartz solubility in Thomas et al.'s (Contrib Mineral Petrol 160:743-759, 2010) calibration represent the equilibrium concentrations of Ti in quartz.

Impact of organic solvents and environmental pollutants on the physiological function in petrol filling workers.

PubMed

Uzma, Nazia; Salar, B M Khaja Mohinuddin; Kumar, B Santhosh; Aziz, Nusrat; David, M Anthony; Reddy, V Devender

2008-09-01

Long term exposure to solvents and air pollutants can lead to deleterious effects on respiratory, haematological and thyroid functioning. The aim of this study was to investigate whether chronic exposure to solvents like benzene and pollutants like carbon monoxide in petrol filling workers had adverse effect on blood parameters, thyroid and respiratory functions. The study group consisted of 42 healthy, non-smoker petrol filling workers, aged 20-50 years with work (exposure) duration from 2-15 years while 36 healthy subjects of the same age group served as controls. Physical examination and measurement of pulmonary functions by portable electronic spirometer were performed. Complete blood pictures (CBP) were determined by normal haematology lab procedure and hormones by Chemiluminescence immunoassay (CLIA) light absorption techniques. There was a significant decrease in the lung volumes and capacities; the restrictive pattern was more prevalent in the workers when compared with the control groups. But in the workers exposed for long period (more than 10 years) the restrictive pattern was changed to mixed pattern. A significant increase in haemoglobin (Hb) (>16 mg %) and red blood cells (RBC) (5.4 million cells/mm3) were observed in workers with longer period of exposure when compared with the control subjects (14.483 mg% and 4.83 million cells/mm3 for Hb and RBC respectively). White blood cell count except eosinophils and platelets were significantly lower in workers compared to controls. Marked increase in the tetra iodothyroinine (T4), free thyroxine (T4F) level and significant decrease in thyroid stimulating hormones (TSH), and tri-iodothyronine (T3) were observed between long term exposed and non-exposed groups. Till now researchers focused only on the effect of solvents in workers professionally exposed to solvents without considering the effect of concomittant air pollution. The result obtained from present study indicates that there is a significant toxic effect of solvents and air pollutants on workers exposed for longer duration. Improved detection and prevention technologies are needed to answer environmentally related health questions for petrol filling workers.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nai-Yang, S.

The Chinese National Standard for Emission from Vehicles was published in 1983. The most important one is Emission Standards for Pollutants at Idle Speed from Road Vehicles with Petrol Engines. This paper discusses experiences gained and lessons learned since publication.

The Closure of the Cycle: Enzymatic Synthesis and Functionalization of Bio-Based Polyesters.

PubMed

Pellis, Alessandro; Herrero Acero, Enrique; Ferrario, Valerio; Ribitsch, Doris; Guebitz, Georg M; Gardossi, Lucia

2016-04-01

The polymer industry is under pressure to mitigate the environmental cost of petrol-based plastics. Biotechnologies contribute to the gradual replacement of petrol-based chemistry and the development of new renewable products, leading to the closure of carbon circle. An array of bio-based building blocks is already available on an industrial scale and is boosting the development of new generations of sustainable and functionally competitive polymers, such as polylactic acid (PLA). Biocatalysts add higher value to bio-based polymers by catalyzing not only their selective modification, but also their synthesis under mild and controlled conditions. The ultimate aim is the introduction of chemical functionalities on the surface of the polymer while retaining its bulk properties, thus enlarging the spectrum of advanced applications. Copyright © 2015 Elsevier Ltd. All rights reserved.

Rate of Heat Release in Diesel Engines

DOT National Transportation Integrated Search

1977-10-01

In this report, the concept of heat release in diesel engines is compared with reaction rates in petrol engines as a means of describing combustion. The intimate relationships between heat release, cylinder pressure development and cylinder pressure ...

Cost effectiveness of introducing a new European evaporative emissions test procedure for petrol vehicles

NASA Astrophysics Data System (ADS)

Haq, Gary; Martini, Giorgio; Mellios, Giorgos

2014-10-01

Evaporative emissions of non-methane volatile organic compounds (NMVOCs) arise from the vehicle's fuel system due to changes in ambient and vehicle temperatures, and contribute to urban smog. This paper presents an economic analysis of the societal costs and benefits of implementing a revised European evaporative emission test procedure for petrol vehicles under four scenarios for the period 2015-2040. The paper concludes that the most cost-effective option is the implementation of an aggressive purging strategy over 48 h and improved canister durability (scenario 2+). The average net benefit of implementing this scenario is €146,709,441 at a 6% discount rate. Per vehicle benefits range from €6-9 but when fuel savings benefits are added, total benefits range from €13-18. This is compared to average additional cost per vehicle of €9.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Valery, N.

The calorific values of the fuels being studied were compared. Petrol is the most efficient, followed by methane in the form of LGN, then methanol and liquid hydrogen. Hydrogen is attractive only on a weight basis, but the storage problems are serious for its liquefied state. Liquid methane requires the same costly storage equipment as hydrogen, making it prohibitive for road vehicles. Methanol is a clean burning fuel and manufacturing processes are being developed. Tests are being sponsored by the Office of Coal Research and the American Gas Association and large-scale commercial plants could be capable of being onstream bymore » 1978. Synthetic crude oil has been manufactured in Sasol, South Africa since 1955. The technique is based on the Fischer-Tropsch process for synthesizing oil from coal, not only making synthetic petrol from coal but also the full range of products normally derived from crude oil. (MCW)« less

Development of haemostatic decontaminants for the treatment of wounds contaminated with chemical warfare agents. 1: evaluation of in vitro clotting efficacy in the presence of certain contaminants.

PubMed

Hall, Charlotte A; Lydon, Helen L; Dalton, Christopher H; Chipman, J K; Graham, John S; Chilcott, Robert P

2015-05-01

The treatment of penetrating, haemorrhaging injuries sustained within a hazardous environment may be complicated by contamination with toxic chemicals. There are currently no specific medical countermeasures for such injuries. Haemostats with an absorbent mechanism of action have the potential to simultaneously stop bleeding and decontaminate wounds. However, a primary requirement of a 'haemostatic decontaminant' is the retention of clotting function in the presence of chemical contaminants. Thus, the aim of this study was to investigate the haemostatic efficacy of seven commercially available haemostats in the presence of toxic chemicals (soman, VX, sulphur mustard, petrol, aviation fuel and motor oil). Clot viscosity was assessed ex vivo using thrombelastography following treatment of pig blood with: (i) toxic chemical; (ii) haemostat; or (iii) haemostat in combination with toxic chemical. Several contaminants (VX, petrol and GD) were found to be pro-haemostatic and none had an adverse effect on the rate with which the test products attained haemostasis. However, the total clot strength for blood treated with certain haemostats in the presence of sulphur mustard, soman and petrol was significantly decreased. Three test products failed to demonstrate haemostatic function in this ex vivo (thrombelastography) model; this was tentatively ascribed to the products achieving haemostasis through a tamponade mechanism of action, which can only be replicated using in vivo models. Overall, this study has identified a number of commercial products that may have potential as haemostatic decontaminants and warrant further investigation to establish their decontaminant efficacy. Copyright © 2014 John Wiley & Sons, Ltd.

Science Notes.

ERIC Educational Resources Information Center

School Science Review, 1985

1985-01-01

Presents 23 experiments, demonstrations, activities, and computer programs in biology, chemistry, and physics. Topics include lead in petrol, production of organic chemicals, reduction of water, enthalpy, X-ray diffraction model, nuclear magnetic resonance spectroscopy, computer simulation for additive mixing of colors, Archimedes Principle, and…

EVALUATION OF THE BIOGENESIS SOIL WASHING TECHNOLOGY

EPA Science Inventory

The BioGenesis Enterprises, Inc. (BioGenesis) soil washing technology was demonstrated as part of the US Environmental Protection Agency's (EPA) Superfund Innovative Technology Evaluation (SITE) program in November 1992. The demonstration was conducted over three days at a petrol...

Oxygen isotope heterogeneity of the mantle beneath the Canary Islands: a discussion of the paper of Gurenko et al.

NASA Astrophysics Data System (ADS)

Day, James M. D.; Macpherson, Colin G.; Lowry, David; Pearson, D. Graham

2012-07-01

Gurenko et al. (Contrib Mineral Petrol 162:349-363, 2011) report laser-assisted fluorination (LF) and secondary ionization mass spectrometry (SIMS) 18O/16O datasets for olivine grains from the Canary Islands of Gran Canaria, Tenerife, La Gomera, La Palma and El Hierro. As with prior studies of oxygen isotopes in Canary Island lavas (e.g. Thirlwall et al. Chem Geol 135:233-262, 1997; Day et al. Geology 37:555-558, 2009, Geochim Cosmochim Acta 74:6565-6589, 2010), these authors find variations in δ18Ool (~4.6-6.0 ‰) beyond that measured for mantle peridotite olivine (Mattey et al. Earth Planet Sci Lett 128:231-241, 1994) and interpret this variation to reflect contributions from pyroxenite-peridotite mantle sources. Furthermore, Gurenko et al. (Contrib Mineral Petrol 162:349-363, 2011) speculate that δ18Ool values for La Palma olivine grains measured by LF (Day et al. Geology 37:555-558, 2009, Geochim Cosmochim Acta 74:6565-6589, 2010) may be biased to low values due to the presence of altered silicate, possibly serpentine. The range in δ18Ool values for Canary Island lavas are of importance for constraining their origin. Gurenko et al. (Contrib Mineral Petrol 162:349-363, 2011) took a subset (39 SIMS analyses from 13 grains from a single El Hierro lava; EH4) of a more extensive dataset (321 SIMS analyses from 110 grains from 16 Canary Island lavas) to suggest that δ18Ool is weakly correlated ( R 2 = 0.291) with the parameter used by Gurenko et al. (Earth Planet Sci Lett 277:514-524, 2009) to describe the estimated weight fraction of pyroxenite-derived melt ( Xpx). With this relationship, end-member δ18O values for HIMU-peridotite (δ18O = 5.3 ± 0.3 ‰) and depleted pyroxenite (δ18O = 5.9 ± 0.3 ‰) were defined. Although the model proposed by Gurenko et al. (Contrib Mineral Petrol 162:349-363, 2011) implicates similar pyroxenite-peridotite mantle sources to those proposed by Day et al. (Geology 37:555-558, 2009, Geochim Cosmochim Acta 74:6565-6589, 2010) and Day and Hilton (Earth Planet Sci Lett 305:226-234, 2011), there are significant differences in the predicted δ18O values of end member components in the two models. In particular, Day et al. (Geochim Cosmochim Acta 74:6565-6589, 2010) proposed a mantle source for La Palma lavas with low-δ18O (<5 ‰), rather than higher-δ18O (c.f. the HIMU-peridotite composition of Gurenko et al. in Contrib Mineral Petrol 162:349-363, 2011). Here we question the approach of using weakly correlated variations in δ18Ool and the Xpx parameter to define mantle source oxygen isotope compositions, and provide examples of why this approach appears flawed. We also provide reasons why the LF datasets previously published for Canary Island lavas remain robust and discuss why LF and SIMS data may provide complementary information on oxygen isotope variations in ocean island basalts (OIB), despite unresolved small-scale uncertainties associated with both techniques.

Reconstructing the plumbing system of Krakatau volcano

NASA Astrophysics Data System (ADS)

Troll, Valentin R.; Dahrén, Börje; Deegan, Frances M.; Jolis, Ester M.; Blythe, Lara S.; Harris, Chris; Berg, Sylvia E.; Hilton, David R.; Freda, Carmela

2014-05-01

Crustal contamination of ascending arc magmas is generally thought to be significant at lower- to mid-crustal magma storage levels where magmas inherit their chemical and isotopic character by blending, assimilation and differentiation [1]. Anak Krakatau, like many other volcanoes, erupts shallow-level crustal xenoliths [2], indicating a potential role for upper crustal modification and hence late-stage changes to magma rheology and thus eruptive behaviour. Distinguishing deep vs. shallow crustal assimilation processes at Krakatau, and elsewhere, is therefore crucial to understand and assess pre-eruptive magmatic conditions and their associated hazard potential. Here we report on a multi-disciplinary approach to unravel the crustal plumbing system of the persistently-active and dominantly explosive Anak Krakatau volcano [2, 3]. We employ rock-, mineral- and gas-isotope geochemistry and link these results with seismic tomography [4]. We show that pyroxene crystals formed at mid- and lower-crustal levels (9-11 km) and carry almost mantle-like isotope signatures (O, Sr, Nd, He), while feldspar crystals formed dominantly at shallow levels (< 5km) and display unequivocal isotopic evidence for late stage contamination (O, Sr, Nd). Coupled with tomographic evidence, the petrological and geochemical data place a significant element of magma-crust interaction (and hence magma storage) into the uppermost, sediment-rich crust beneath the volcano. Magma - sediment interaction in the uppermost crust offers a likely explanation for the compositional variations in recent Krakatau magmas and most probably provides extra impetus to increased explosivity at Anak Krakatau. [1] Annen, et al., 2006. J. Petrol. 47, 505-539. [2] Gardner, et al., 2013. J. Petrol. 54, 149-182. [3] Dahren, et al., 2012. Contrib. Mineral. Petrol. 163, 631-651. [4] Jaxybulatov, et al., 2011. J. Volcanol. Geoth. Res. 206, 96-105.

Shallow-level magma-sediment interaction and explosive behaviour at Anak Krakatau (Invited)

NASA Astrophysics Data System (ADS)

Troll, V. R.; Jolis, E. M.; Dahren, B.; Deegan, F. M.; Blythe, L. S.; Harris, C.; Berg, S. E.; Hilton, D. R.; Freda, C.

2013-12-01

Crustal contamination of ascending arc magmas is generally thought to be a significant process which occurs at lower- to mid-crustal magma storage levels where magmas inherit their chemical and isotopic character by blending, assimilation and differentiation [1]. Anak Krakatau, like many other volcanoes, erupts shallow-level crustal xenoliths [2], indicating a potential role for upper crustal modification and hence late-stage changes to magma rheology and thus potential eruptive behaviour. Distinguishing deep vs. shallow crustal contamination processes at Krakatau, and elsewhere, is therefore crucial to understand and assess pre-eruptive magmatic conditions and their associated hazard potential. Here we report on a multi-disciplinary approach to unravel the crustal plumbing system of the persistently-active and dominantly explosive Anak Krakatau volcano [2, 3], employing rock-, mineral- and gas-isotope geochemistry and link these results with seismic tomography [4]. We show that pyroxene crystals formed at mid- and lower-crustal levels (9-11 km) and carry almost mantle-like isotope signatures (O, Sr, Nd, He), while feldspar crystals formed dominantly at shallow levels (< 5km) and display unequivocal isotopic evidence for late stage contamination (O, Sr, Nd). This obeservation places a significant element of magma-crust interaction into the uppermost, sediment-rich crust beneath the volcano. Magma storage in the uppermost crust can thus offer a possible explanation for the compositional modifications of primitive Krakatau magmas, and likely provides extra impetus to increased explosivity at Anak Krakatau. [1] Annen, et al., 2006. J. Petrol. 47, 505-539. [2] Gardner, et al., 2013. J. Petrol. 54, 149-182. [3] Dahren, et al., 2012. Contrib. Mineral. Petrol. 163, 631-651. [4] Jaxybulatov, et al., 2011. J. Volcanol. Geoth. Res. 206, 96-105.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pirhonen, P.

Life-cycle assessment is usually based on regular discharges that occur at a more or less constant rate. Nevertheless, the more factors that are taken into account in the LCA the better picture it gives on the environmental aspects of a product. In this study an approach to incorporate accidental releases into a products` life-cycle assessment was developed. In this approach accidental releases are divided into two categories. The first category consists of those unplanned releases which occur with a predicted level and frequency. Due to the high frequency and small release size at a time, these accidental releases can bemore » compared to continuous emissions. Their global impacts are studied in this approach. Accidental releases of the second category are sudden, unplanned releases caused by exceptional situations, e.g. technical failure, action error or disturbances in process conditions. These releases have a singular character and local impacts are typical of them. As far as the accidental releases of the second category are concerned, the approach introduced in this study results in a risk value for every stage of a life-cycle, the sum of which is a risk value for the whole life-cycle. Risk value is based on occurrence frequencies of incidents and potential environmental damage caused by releases. Risk value illustrates the level of potential damage caused by accidental releases related to the system under study and is meant to be used for comparison of these levels of two different products. It can also be used to compare the risk levels of different stages of the life-cycle. An approach was illustrated using petrol as an example product. The whole life-cycle of petrol from crude oil production to the consumption of petrol was studied.« less

Neuropathy in a petrol sniffer.

PubMed

Hall, D M; Ramsey, J; Schwartz, M S; Dookun, D

1986-09-01

A 4 year old boy developed a profound motor neuropathy after repeated deliberate inhalation of petroleum vapour. The condition was characterised by extreme slowing of the nerve conduction velocity. He made a gradual recovery over six months. The neuropathy was attributed to the N-hexane component of petroleum.

Knock detection system to improve petrol engine performance, using microphone sensor

NASA Astrophysics Data System (ADS)

Sujono, Agus; Santoso, Budi; Juwana, Wibawa Endra

2017-01-01

An increase of power and efficiency of spark ignition engines (petrol engines) are always faced with the problem of knock. Even the characteristics of the engine itself are always determined from the occurrence of knock. Until today, this knocking problem has not been solved completely. Knock is caused by principal factors that are influenced by the engine rotation, the load or opening the throttle and spark advance (ignition timing). In this research, the engine is mounted on the engine test bed (ETB) which is equipped with the necessary sensors. Knock detection using a new method, which is based on pattern recognition, which through the knock sound detection by using a microphone sensor, active filter, the regression of the normalized envelope function, and the calculation of the Euclidean distance is used for identifying knock. This system is implemented with a microcontroller which uses fuzzy logic controller ignition (FLIC), which aims to set proper spark advance, in accordance with operating conditions. This system can improve the engine performance for approximately 15%.

Impact of bioethanol fuel implementation in transport based on modelled acetaldehyde concentration in the urban environment.

PubMed

Sundvor, Ingrid; López-Aparicio, Susana

2014-10-15

This study shows the results obtained from emission and air dispersion modelling of acetaldehyde in the city of Oslo and associated with the circulation of bioethanol vehicles. Two scenarios of bioethanol implementation, both realistic and hypothetical, have been considered under winter conditions; 1) realistic baseline scenario, which corresponds to the current situation in Oslo where one bus line is running with bioethanol (E95; 95% ethanol-5% petrol) among petrol and diesel vehicles; and 2) a hypothetical scenario characterized by a full implementation of high-blend bioethanol (i.e. E85) as fuel for transportation, and thus an entire bioethanol fleet. The results indicate that a full implementation of bioethanol will have a certain impact on urban air quality due to direct emissions of acetaldehyde. Acetaldehyde emissions are estimated to increase by 233% and concentration levels increase up to 650% with regard to the baseline. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Survey on how fluctuating petrol prices are affecting Malaysian large city dwellers in changing their trip patterns

NASA Astrophysics Data System (ADS)

Rohani, M. M.; Pahazri, N.

2018-04-01

Rising fuel prices shocks have a significant impact on the way of life of most Malaysians. Due to the rising of oil prices, the costs of travel for private vehicle users are therefore increasing. The study was conducted based on the objective of studying the impact of rising fuel prices on three types of trip patterns of Malaysians who are living in the city areas. The three types of trip patterns are, workplaces trip, leisure trip and personal purposes trip during the weekdays. This study was conducted by distributing questionnaires to respondents of private vehicle users in selected city such as Johor Bahru, Kuala Lumpur, Putrajaya, Melaka, Perak, Selangor and Kelantan. This study, found that the trip patterns of those who were using their own vehicles had changed after the rising of fuel prices. The changes showed that many private vehicle users were taking steps to save money on petrol by adjusting their trips.

Evolving Pb isotope signatures of London airborne particulate matter (PM 10)-constraints from on-filter and solution-mode MC-ICP-MS.

PubMed

Noble, Stephen R; Horstwood, Matthew S A; Davy, Pamela; Pashley, Vanessa; Spiro, Baruch; Smith, Steve

2008-07-01

Pb isotope compositions of biologically significant PM(10) atmospheric particulates from a busy roadside location in London UK were measured using solution- and laser ablation-mode MC-ICP-MS. The solution-mode data for PM(10) sampled between 1998-2001 document a dramatic shift to increasingly radiogenic compositions as leaded petrol was phased out. LA-MC-ICP-MS isotope analysis, piloted on a subset of the available samples, is shown to be a potential reconnaissance analytical technique. PM(10) particles trapped on quartz filters were liberated from the filter surface, without ablating the filter substrate, using a 266 nm UV laser and a dynamic, large diameter, low-fluence ablation protocol. The Pb isotope evolution noted in the London data set obtained by both analytical protocols is similar to that observed elsewhere in Western Europe following leaded petrol elimination. The data therefore provide important baseline isotope composition information useful for continued UK atmospheric monitoring through the early 21(st) century.

Higher fuel prices are associated with lower air pollution levels.

PubMed

Barnett, Adrian G; Knibbs, Luke D

2014-05-01

Air pollution is a persistent problem in urban areas, and traffic emissions are a major cause of poor air quality. Policies to curb pollution levels often involve raising the price of using private vehicles, for example, congestion charges. We were interested in whether higher fuel prices were associated with decreased air pollution levels. We examined an association between diesel and petrol prices and four traffic-related pollutants in Brisbane from 2010 to 2013. We used a regression model and examined pollution levels up to 16 days after the price change. Higher diesel prices were associated with statistically significant short-term reductions in carbon monoxide and nitrogen oxides. Changes in petrol prices had no impact on air pollution. Raising diesel taxes in Australia could be justified as a public health measure. As raising taxes is politically unpopular, an alternative political approach would be to remove schemes that put a downward pressure on fuel prices, such as industry subsidies and shopping vouchers that give fuel discounts. Copyright © 2014 Elsevier Ltd. All rights reserved.

Measuring market share of petrol stations using conditional probability approach

NASA Astrophysics Data System (ADS)

Sharif, Shamshuritawati; Lwee, Xue Yin

2017-05-01

Oil and gas production is the strength of Malaysia's growth over past decades. It is one of the most strategic economic branches in the world. Since the oil industry is essential for the economic growth of a country, only a few undertakings have been achieved to establish. It is a very risky business. Therefore the dealer must have some information in hand before setting up a new business plan. Understanding the current business situation is an important strategy to avoid risky ventures. In this study, the aim is to deliver a very simple but essential way to identify the market share based on customer's choice factors. This approach is presented to encourage the non-statisticians to use it easily in helping their business performance. From this study, the most important factors differ from one station to another station. The results show that the factors of customer's choice for BHPetrol, Caltex, PETRON, PETRONAS and SHELL are site location, service quality, service quality, size of the petrol station, and brand image, respectively.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scott, W.E.

As Australia's self-sufficiency in petroleum is rapidly declining and a liquid-fuel crisis looms large on the horizon, the government is backing research into biomass-derived fuels. An Australian Commonwealth Scientific and Industrial Research Organization group determined that such fuels could play a major role in supplementing the liquid fuels. They envisaged that two kinds of alcohol could be used. Ethanol would be produced by the fermentation of starches and sugars derived from special energy crops. A similar compound, methanol, or wood alcohol, would be made from fibrous or woody plant materials, namely: cereal straw, bagasse, logging and timber-mill wastes, and othermore » residues. Recently, trials were begun with a pilot-scale digester to convert waste foods into methane. Working properly, it is expected to generate the equivalent of about 30 litres of petrol per day. Generally, production costs of biomass-derived fuels are expected to be about 2 to 3 times those of petrol, with world crude oil prices at October 1978 levels.« less

Incorporating high speed passenger rail into a multimodal network model for improved regional transportation planning.

DOT National Transportation Integrated Search

2014-05-01

With increasing demand and rising fuel costs, both travel time and cost of intercity passenger : transportation are becoming increasingly significant. Around the world, high-speed rail (HSR) is seen as a : way to mitigate the risk of volatile petrole...

Neuropathy in a petrol sniffer.

PubMed Central

Hall, D M; Ramsey, J; Schwartz, M S; Dookun, D

1986-01-01

A 4 year old boy developed a profound motor neuropathy after repeated deliberate inhalation of petroleum vapour. The condition was characterised by extreme slowing of the nerve conduction velocity. He made a gradual recovery over six months. The neuropathy was attributed to the N-hexane component of petroleum. PMID:3021070

Engineering yeasts for xylose metabolism

Treesearch

Thomas W. Jeffries

2006-01-01

Technologies for the production of alternative fuels are receiving increased attention owing to concerns over the rising cost of petrol and global warming. One such technology under development is the use of yeasts for the commercial fermentation of xylose to ethanol. Several approaches have been employed to engineer xylose metabolism. These involve modeling, flux...

Turkey: A Strategic Ally.

DTIC Science & Technology

1982-04-16

France in 1830, and Tunisia in 1881. Great Britain took the Island of Cyprus in 1878 and Egypt in 1882. 3 In view of the diminishing fortunes of the...boats, 49 coastal petrol boats, 26 minesweepers, 10 mine layers, 77 amphibious ships/boats, one depot ship and five tankers.40 The command also has

The New Great Game in Muslim Central Asia

DTIC Science & Technology

1996-01-01

and maci]ine tools, petrol - chemicals, agro-processing and textiles. ’’~ 14 THE NEW GREAT GAME IN MUSLIM CENTRAL ASIA Kazakhstan is well endowed...Algeria, Tunisia , and Morocco---are keeping a wary eye. But at the popular level, this pan-Islmnism has the potential to attract a considerable amount of

The Petrol Station and the Internet Cafe: Rural Technospaces for Youth.

ERIC Educational Resources Information Center

Laegran, Anne Sofie

2002-01-01

A study in two Norwegian villages focused on the local gas station and the Internet cafe as "technospaces" for rural youth cultures--spaces at the intersection of technology and human interaction. The car and the Internet were given different symbolic and utility values in various youth subcultures. Local contexts influenced technology…

EPA/IFP EUROPEAN WORKSHOP ON THE EMISSION ON NITROUS OXIDE FROM FOSSIL FUEL COMBUSTION

EPA Science Inventory

The report summarizes the proceedings of an EPA/Institut Francais du Petrole (IFP) cosponsored workshop addressing direct nitrous oxide (N2O) emission from fossil fuel combustion. The third in a series, it was held at the IFP in Rueil-Malmaison, France, on June 1-2, 1988. Increas...

Comparison of the mopping ability of chemically modified and unmodified biological wastes on crude oil and its lower fractions.

PubMed

Nduka, John Kanayochukwu; Ezenweke, Linus Obi; Ezenwa, Emmanuel Tagbo

2008-11-01

Activated and unactivated powders of goat hair and coir (coconut husk) separated into two particle sizes were used to mop up spills of crude oil, diesel, kerosene and petrol. It was observed that the materials (sorbents) mopped up appreciable volumes of the hydrocarbon liquids (sorbates) within 90 min of contact. Activation, particle size of sorbents and molecular weight (chain length) of sorbates (hydrocarbon) are major determining factors. Carbonization and particle size enhanced the mopping ability as follows--carbonized 325 microm > uncarbonized 325 microm > carbonized 625 microm > uncarbonized 625 microm, thus activated sorbents with large surface area (small particle size) mopped more hydrocarbons than unactivated of the same particle size. The sorbates were mopped in the order--crude oil > diesel > kerosene > petrol. It was further observed that goat hair (keratin protein) with oleophilic and aquaphobic properties adsorbed more of all the hydrocarbons than coir at all sizes and treatment. Large quantities of the mopped oils were recovered by mere pressing while the waste sorbents with 0.5-2.0% leachable residual oil could be utilized as alternative to fire wood.

Helmet use and associated factors among Thai motorcyclists during Songkran festival.

PubMed

Siviroj, Penprapa; Peltzer, Karl; Pengpid, Supa; Morarit, Sompong

2012-09-10

The aim of this study was to assess helmet use and associated factors among motorcycle riders during Songkran festival in Thailand. A cross-sectional survey was conducted to determine the prevalence of helmet use among Thai motorcycle riders (sample size = 18,998) during four days of the Songkran festival. For this sample, the population of motorcycle riders was consecutively selected using quota sampling from 12 petrol stations in four provinces from each of the four main geographical regions of Thailand. The study was conducted at petrol stations at roads in town, outside town and highway at different time intervals when trained field staff administered a structured questionnaire and performed an observation checklist. Results indicate that 44.2% of the motorcycle riders and 72.5% of the motorcycle passengers had not been using a helmet. In multivariable analysis demographics, environmental factors, helmet use experiences and attitudes and recalling a lower exposure to road safety awareness (RSA) campaign were associated with non-helmet use among motorcyclists. It appears that the RSA campaign may have some positive effect on reducing non-helmet use among motorcycle riders during the Songkran festival.

A fundamental dispute: A discussion of "On some fundamentals of igneous petrology" by Bruce D. Marsh, Contributions to Mineralogy and Petrology (2013) 166: 665-690

NASA Astrophysics Data System (ADS)

Latypov, Rais; Morse, Tony; Robins, Brian; Wilson, Richard; Cawthorn, Grant; Tegner, Christian; Holness, Marian; Lesher, Charles; Barnes, Steve; O'Driscoll, Brian; Veksler, Ilya; Higgins, Michael; Wilson, Allan; Namur, Olivier; Chistyakova, Sofya; Naslund, Richard; Thy, Peter

2015-02-01

Marsh (Contrib Miner Petrol 166:665-690, 2013) again claims that crystal-free basalt magmas are unable to differentiate in crustal magma chambers and regards layered intrusions as primarily due to the repeated emplacement of crystal suspensions. He ignores an earlier critique of his unconventional inferences (Latypov, J Petrol 50:1047-1069, 2009) as well as a wealth of petrographic, geochemical and experimental evidence supporting the dominant role of fractional crystallization in the solidification of layered intrusions. Most tellingly, the cryptic variations preserved in the Skaergaard and many other basaltic layered intrusions would require an exceedingly implausible sequence of phenocrystic magmas but are wholly consistent with in situ fractional crystallization. A major flaw in Marsh's hypothesis is that it dismisses progressive fractional crystallization within any magma chamber and hence prohibits the formation of crystal slurries with phenocrysts and melts that change systematically in composition in any feeder system. This inherent attribute of the hypothesis excludes the formation of layered intrusions anywhere.

Influence of driving cycles on unit emissions from passenger cars

NASA Astrophysics Data System (ADS)

Joumard, R.; André, M.; Vidon, R.; Tassel, P.; Pruvost, C.

Small samples of petrol engine or diesel cars, equipped with or without catalysts, were tested over 36 driving cycles divided into four categories - standard cycles and three sets of cycles more representative of real-world driving conditions. The tests addressed standard gaseous pollutants and fuel consumption and also less frequently measured pollutant such as CH 4. In the first part of this paper we examine cold emissions in order to assess the duration of the cold start impact and the representativity of the cold ECE15 cycle. Then unit emissions are compared over the four driving cycle families. As compared to representative cycles, the standardised cycles underestimate hot emissions by almost 50% for petrol engine cars and 30% for diesel vehicles. Conversely, the results obtained for the three representative cycle families are in relatively close agreement with each other - within approximately 10%. However, the cinematic properties of the three families differ. Finally, we demonstrate that weighting all emission data equally, not taking into account the weight of each cycle in overall traffic, introduces significant biases, particularly when plotting emission vs. average speed curves.

Development of wireless vehicle remote control for fuel lid operation

NASA Astrophysics Data System (ADS)

Sulaiman, N.; Jadin, M. S.; Najib, M. S.; Mustafa, M.; Azmi, S. N. F.

2018-04-01

Nowadays, the evolution of the vehicle technology had made the vehicle especially car to be equipped with a remote control to control the operation of the locking and unlocking system of the car’s door and rear’s bonnet. However, for the fuel or petrol lid, it merely can be opened from inside the car’s cabin by handling the fuel level inside the car’s cabin to open the fuel lid. The petrol lid can be closed by pushing the lid by hand. Due to the high usage of using fuel lever to open the fuel lid when refilling the fuel, the car driver might encounter the malfunction of fuel lid (fail to open) when pushing or pulling the fuel lever. Thus, the main aim of the research is to enhance the operation of an existing car remote control where the car fuel lid can be controlled using two techniques; remote control-based and smartphone-based. The remote control is constructed using Arduino microcontroller, wireless sensors and XCTU software to set the transmitting and receiving parameters. Meanwhile, the smartphone can control the operation of the fuel lid by communicating with Arduino microcontroller which is attached to the fuel lid using Bluetooth sensor to open the petrol lid. In order to avoid the conflict of instruction between wireless systems with the existing mechanical-based system, the servo motor will be employed to release the fuel lid merely after receiving the instruction from Arduino microcontroller and smartphone. As a conclusion, the prototype of the multipurpose vehicle remote control is successfully invented, constructed and tested. The car fuel lid can be opened either using remote control or smartphone in a sequential manner. Therefore, the outcome of the project can be used to serve as an alternative solution to solve the car fuel lid problem even though the problem rarely occurred.

Simulation of fuel demand for wood-gas in combustion engine

NASA Astrophysics Data System (ADS)

Botwinska, Katarzyna; Mruk, Remigiusz; Tucki, Karol; Wata, Mateusz

2017-10-01

In the era of the oil crisis and proceeding contamination of the natural environment, it is attempted to substitute fossil raw materials with alternative carriers. For many years, road transport has been considered as one of the main sources of the substances deteriorating air quality. Applicable European directives oblige the member states to implement biofuels and biocomponents into the general fuel market, however, such process is proceeding gradually and relatively slowly. So far, alternative fuels have been used on a large scale to substitute diesel fuel or petrol. Derivatives of vegetable raw materials, such as vegetable oils or their esters and ethanol extracted from biomass, are used to that end. It has been noticed that there is no alternative to LPG which, due to financial reasons, is more and more popular as fuel in passenger cars. In relation to solutions adopted in the past, it has been decided to analyse the option of powering a modern passenger car with wood gas - syngas. Such fuel has been practically used since the 1920's. To that end, a computer simulation created in SciLab environment was carried out. Passenger car Fiat Seicento, fitted with Fire 1.1 8V petrol engine with power of 40kW, whose parameters were used to prepare the model, was selected as the model vehicle. The simulation allows the determination of engine demand on the given fuel. Apart from the wood gas included in the title, petrol, methane and LPG were used. Additionally, the created model enables the determination of the engine power at the time of the indicated fuels supply. The results obtained in the simulation revealed considerable decrease in the engine power when the wood gas was supplied and the increased consumption of this fuel. On the basis of the analysis of the professional literature describing numerous inconveniences connected with the use of this fuel as well as the obtained results, it has been established that using the wood gas as alternative fuel is currently unjustified.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cook, C.M.; Lanaras, T.; Sgardelis, S.P.

The combustion of petroleum fuel and exhaust emissions are major sources of atmospheric pollution in cities which result in the deposition of toxic substances, particularly heavy metals, in the surface layers of soils. Lead in particular enters the environment from the use of tetraethyl lead as an antiknock agent for petrol engines constituting 21% of fine particles emitted from cars burning leaded petrol. Antiwear protectants incorporated in lubricants often contain Cd, Cr, Cu, Hg, Ni, Pb and/or Zn which are also released into the environment by inefficient engines and irresponsible dumping of engine oils. Zn from tyre wear and Cumore » from diesel engines also add considerably to the environmental metal burden. Lowering of the permitted lead content of petrol and the growing use of unleaded fuel are expected to lead to reductions in the environmental lead burden, however, until unleaded fuel becomes universally accepted lead contamination, particularly of roadside soils and vegetation is a major cause for concern. A direct relationship between car exhaust, the Pb content of needles of Abies alba and reduced growth has been observed and can extend hundreds of metres from major highways. Lead tolerance has been observed in higher plants growing mine waste soils and to a lesser extent on lead-contaminated roadside soils. Automobiles which are responsible for line sources of pollution emissions in rural and suburban areas have a more far-reaching impact on roadside vegetation, already under considerable stress, in urban areas. Information on heavy metal effects on vegetation in urban environments however, are scarce. Modeling and multivariate analysis of a few of the factors involved have provided only limited data related to plant performance in these complex environments. Therefore in this study, the extent of heavy metal pollution by Pb, Zn, Cu and Cd in soils and in dandelion plants in the city of Thessaloniki has been examined. 20 refs., 2 figs., 3 tabs.« less

78 FR 73914 - In the Matter of ICC Worldwide, Inc., Innova Pure Water, Inc., Paladin Holdings, Inc., Performing...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-12-09

... Pure Water, Inc., Paladin Holdings, Inc., Performing Brands, Inc., Petrol Oil and Gas, Inc., Platinum Research Organization, Inc., Renew Energy Resources, Inc., and Vital Living, Inc.; Order of Suspension of... Water, Inc. because it has not filed any periodic reports since the period ended March 31, 2007. It...

An Example of the Quality of Students' Understanding: Initial Conceptions of Psychology.

ERIC Educational Resources Information Center

Gibbs, Graham; And Others

This paper discusses a survey undertaken to determine conceptions of psychology held by college students in an introductory social science course. Twenty-nine students were queried at the beginning of the course regarding the open-ended question, "If Esso garages were to invite a psychologist to improve the efficiency of petrol pump attendants,…

Antibacterial and antifungal activities of Dracontomelon dao.

PubMed

Khan, M R; Omoloso, A D

2002-07-01

The crude methanolic extracts of the leaves, stem and root barks of Drancantomelon dao and their subsequent partitioning (petrol, dichloromethane, ethyl acetate, butanol) gave fractions which demonstrated a very good level of broad spectrum antibacterial activity. The dichloromethane and butanol fractions of the leaf were the most active. Only the leaf fractions had antifungal activity, particularly the dichloromethane and butanol.

Architecting Integrated System Health Management for Airworthiness

DTIC Science & Technology

2013-09-01

aircraft safety and reliability through condition-based maintenance [Miller et al., 1991]. With the same motivation, Integrated System Health Management...diagnostics and prognostics algorithms. 2.2.2 Health and Usage Monitoring System (HUMS) in Helicopters Increased demand for improved operational safety ...offshore shuttle helicopters traversing the petrol installations in the North Sea, and increased demand for improved operational safety and reduced

Phases transitions and interfaces in temperature-sensitive colloidal systems

NASA Astrophysics Data System (ADS)

Nguyen, Duc; Schall, Peter

2013-03-01

Colloids are widely used because of their exceptional properties. Beside their own applications in food, petrol, cosmetics and drug industries, photonic, optical filters and chemical sensor, they are also known as powerful model systems to study molecular phase behavior. Here, we examine both aspects of colloids using temperature-sensitive colloidal systems to fully investigate colloidal phase behavior and colloidal assembly.

Simulation of an electric vehicle model on the new WLTC test cycle using AVL CRUISE software

NASA Astrophysics Data System (ADS)

Cristian Cioroianu, Constantin; Marinescu, Dănuţ Gabriel; Iorga, Adrian; Răzvan Sibiceanu, Adrian

2017-10-01

Nowadays, environmental pollution has become a general issue and the automotive industry is probably the most affected. The principal air-quality pollutant emissions from petrol, diesel and LPG engines are carbon dioxide, oxides of nitrogen, un-burnt hydrocarbons. Modern cars produce only quite small quantities of the air quality pollutants, but the emissions from large numbers of cars add to a significant air quality problem. Electric vehicles are an answer to this problem because they have absolutely no emissions. These vehicles have some major disadvantages regarding cost and range. In this paper, an electric vehicle model will be created in the AVL Cruise software. The constructed model is based on the existing Dacia Sandero. Also unlike the real car, the model presented has different characteristics since it is a full electric vehicle. It has an electric motor instead of the petrol engine and a battery pack placed in the trunk. The model will be simulated in order to obtain data regarding vehicle performance, energy consumption and range on the new WLTC test cycle. The obtained know-how will help on later improvements of the electric model regarding methods to increase the vehicle range on the new WLTC test cycle.

Peptide-based ambidextrous bifunctional gelator: applications in oil spill recovery and removal of toxic organic dyes for waste water management.

PubMed

Basu, Kingshuk; Nandi, Nibedita; Mondal, Biplab; Dehsorkhi, Ashkan; Hamley, Ian W; Banerjee, Arindam

2017-12-06

A low molecular weight peptide-based ambidextrous gelator molecule has been discovered for efficient control of water pollution. The gelator molecules can gel various organic solvents with diverse polarity, e.g. n -hexane, n -octane, petroleum ether, petrol, diesel, aromatic solvents like chlorobenzene, toluene, benzene, o -xylene and even aqueous phosphate buffer of pH 7.5. These gels have been thoroughly characterized using various techniques including field emission scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray powder diffraction analysis, small angle X-ray scattering and rheological experiments. Interestingly, hydrogel obtained from the gelator molecule has been found to absorb toxic organic dyes (both cationic and anionic dyes) from dye-contaminated water. The gelator molecule can be reused for several cycles, indicating its possible future use in waste water management. Moreover, this gelator can selectively gel petrol, diesel, pump oil from an oil-water mixture in the presence of a carrier solvent, ethyl acetate, suggesting its efficient application for oil spill recovery. These results indicate that the peptide-based ambidextrous gelator produces soft materials (gels) with dual function: (i) removal of toxic organic dyes in waste water treatment and (ii) oil spill recovery.

Helmet Use and Associated Factors among Thai Motorcyclists during Songkran Festival

PubMed Central

Siviroj, Penprapa; Peltzer, Karl; Pengpid, Supa; Morarit, Sompong

2012-01-01

The aim of this study was to assess helmet use and associated factors among motorcycle riders during Songkran festival in Thailand. A cross-sectional survey was conducted to determine the prevalence of helmet use among Thai motorcycle riders (sample size = 18,998) during four days of the Songkran festival. For this sample, the population of motorcycle riders was consecutively selected using quota sampling from 12 petrol stations in four provinces from each of the four main geographical regions of Thailand. The study was conducted at petrol stations at roads in town, outside town and highway at different time intervals when trained field staff administered a structured questionnaire and performed an observation checklist. Results indicate that 44.2% of the motorcycle riders and 72.5% of the motorcycle passengers had not been using a helmet. In multivariable analysis demographics, environmental factors, helmet use experiences and attitudes and recalling a lower exposure to road safety awareness (RSA) campaign were associated with non-helmet use among motorcyclists. It appears that the RSA campaign may have some positive effect on reducing non-helmet use among motorcycle riders during the Songkran festival. PMID:23202686

Assessing the environmental sustainability of ethanol from integrated biorefineries

PubMed Central

Falano, Temitope; Jeswani, Harish K; Azapagic, Adisa

2014-01-01

This paper considers the life cycle environmental sustainability of ethanol produced in integrated biorefineries together with chemicals and energy. Four types of second-generation feedstocks are considered: wheat straw, forest residue, poplar, and miscanthus. Seven out of 11 environmental impacts from ethanol are negative, including greenhouse gas (GHG) emissions, when the system is credited for the co-products, indicating environmental savings. Ethanol from poplar is the best and straw the worst option for most impacts. Land use change from forest to miscanthus increases the GHG emissions several-fold. For poplar, the effect is opposite: converting grassland to forest reduces the emissions by three-fold. Compared to fossil and first-generation ethanol, ethanol from integrated biorefineries is more sustainable for most impacts, with the exception of wheat straw. Pure ethanol saves up to 87% of GHG emissions compared to petrol per MJ of fuel. However, for the current 5% ethanol–petrol blends, the savings are much smaller (<3%). Therefore, unless much higher blends become widespread, the contribution of ethanol from integrated biorefineries to the reduction of GHG emissions will be insignificant. Yet, higher ethanol blends would lead to an increase in some impacts, notably terrestrial and freshwater toxicity as well as eutrophication for some feedstocks. PMID:24478110

Regeneration of mesoporous silica aerogel for hydrocarbon adsorption and recovery.

PubMed

Zhang, Chengzhao; Dai, Chong; Zhang, Huaqin; Peng, Shitao; Wei, Xin; Hu, Yandi

2017-09-15

Silica aerogel, with mesoporous structure and high hydrophobicity, is a promising adsorbent for oil spill clean-up. To make it economic and environmental-friendly, hydrocarbon desorption and silica aerogel regeneration were investigated. After hydrocarbon desorption at 80°C, silica aerogel maintained its hydrophobicity. After toluene, petrol, and diesel desorption, shrinkage of mesopores (from 19.9 to 16.8, 13.5, and 13.4nm) of silica aerogels occurred, causing decreased adsorption capacities (from 12.4, 11.2, and 13.6 to 12.0, 6.5, and 2.3g/g). Low surface tension of petrol caused high stress on mesopores during its desorption, resulting in significant pore shrinkage. For diesel, its incomplete desorption and oxidation further hindered the regeneration. Therefore, diesel desorption was also conducted at 200°C. Severe diesel oxidation occurred under aerobic condition and destroyed the mesopores. Under anaerobic condition, no diesel oxidation occurred and the decreases in pore size (to 13.2nm) and adsorption efficiency (to 10.0g/g) of regenerated silica aerogels were much less, compared with under aerobic condition. This study provided new insights on silica aerogel regeneration for oil spill clean-up. Copyright © 2017 Elsevier Ltd. All rights reserved.

Experimental study of the P-T stability of phlogopite in metasomatised peridotite with varying H2O contents in the deep cratonic lithosphere

NASA Astrophysics Data System (ADS)

Yaxley, Greg; Rosenthal, Anja

2014-05-01

Phlogopite is an important metasomatic, hydrous, potassic phase in peridotite from on- and off-cratonic lithospheric mantle. It is significant in petrogenesis of exotic mantle-derived magmas such as micaceous kimberlites, ultramafic lamprophyres, kamafugites, lamproites and olivine basanites[1-6]. Along with other potassic hydrous agents (fluids/melts), phlogopite is a major repository for potassium, H2O and F in K-enriched peridotitic mantle down to ~200 km or more (≡6 GPa[7-10]). Although some recent studies delineated phlogopite stability in peridotite at a given bulk H2O content1[1,8-10,12], we lack experimental investigations close to the limits of phlogopite stability in a model mantle composition enriched in K (i.e. by metasomatic agents) with varying amounts of H2O over a pressure range of 4-6 GPa, i.e. from ≡120 to 200 km deep. Variations in the %H2O available however determine the shape and location of the solidus, and hence the onset of partial melting of a K-enriched mantle enriched[8,13]. Our experimental base composition (HPK2) is fertile peridotite + 0.5wt% K2O. Mixes HPK2-0 and HPK2-13 were prepared by blending powdered high purity oxides or carbonates of Si, Ti, Al, Mg, Cr, Ni, Mn, Ca, Na and K. Mg(OH)2 was included in HPK2-13 to produce a mix with 13wt% H2O. HPK2-0 is anhydrous. HPK2-0 and HPK2-13 were blended to create 3 additional mixes with identical compositions but varying H2O contents, nominally 0.2, 2 and 5wt% H2O. Experiments were run in Au, AuPd or graphite (in Pt) capsules at 4-6 GPa and 1050-1350°C. Run products were analysed by EDS on a SEM. Experiments crystallized assemblages of olivine + orthopyroxene ± clinopyroxene ± garnet ± rutile ± phlogopite. We define the temperature stability limit of phlogopite in potassic-peridotite between 1200 and 1250°C at 4 GPa and <1300°C at 5 GPa, consistent with interpolation of data from previous lower[1] and higher pressure[14] investigations. We also demonstrate the leaching effect of large excesses of hydrous fluid. Sub-solidus runs with 13wt% H2O, at P-T conditions within the phlogopite stability field at low %H2O, are phlogopite and clinopyroxene-free, indicating that hydrous-fluids under these conditions may transport significant Na, K, Ca, Al and other solutes[8,12]. References 1 Mengel, K. & Green, D. H. Geol. Soc. Aust. Spec. Publ. 14, 571-581 (1989). 2 Mitchell, R. H. Kimberlites, orangeites, and related rocks. (Plenum Press, 1995). 3 Foley, S. Lithos 28, 435-453 (1992). 4 Prelevic, D. et al. Terra Nova 22, 443-452 (2010). 5 Tappe, S. et al. Earth Planet Sci Lett 256, 433-454 (2007). 6 Rosenthal, A., et al. Earth Planet Sci Lett 284, 236-248 (2009). 7 Foley, S. Geochim Cosmochim Acta 55, 2689-2694 (1991). 8 Green, D. H., et al. Nature 467, 448-497 (2010). 9 Konzett, J., et al. Contrib Mineral Petrol 163, 277-296 (2012). 10 Konzett, J. & Ulmer, P. J Petrol 40, 629-652 (1999). 11 Fumagalli, P., et al. Contrib Mineral Petrol 158, 723-737 (2009). 12 Kovács, I. et al. J Petrol 53, 2067-2093 (2012). 13 Niida, K. & Green, D. H. Contrib Mineral Petrol 135, 18-40 (1999). 14 Luth, R. Am Mineral 82, 1198-1209 (1997).

The isotopic composition of CO in vehicle exhaust

NASA Astrophysics Data System (ADS)

Naus, S.; Röckmann, T.; Popa, M. E.

2018-03-01

We investigated the isotopic composition of CO in the exhaust of individual vehicles. Additionally, the CO2 isotopes, and the CO:CO2, CH4:CO2 and H2:CO gas ratios were measured. This was done under idling and revving conditions, and for three vehicles in a full driving cycle on a testbench. The spread in the results, even for a single vehicle, was large: for δ13 C in CO ∼ -60 to 0‰, for δ18 O in CO ∼ +10 to +35‰, and for all gas ratios several orders of magnitude. The results show an increase in the spread of isotopic values for CO compared to previous studies, suggesting that increasing complexity of emission control in vehicles might be reflected in the isotopic composition. When including all samples, we find a weighted mean for the δ13 C and δ18 O in CO of -28.7 ± 0.5‰ and +24.8 ± 0.3‰ respectively. This result is dominated by cold petrol vehicles. Diesel vehicles behaved as a distinct group, with CO enriched in 13C and depleted in 18O, compared to petrol vehicles. For the H2:CO ratio of all vehicles, we found a value of 0.71 ± 0.31 ppb:ppb. The CO:CO2 ratio, with a mean of 19.4 ± 6.8 ppb:ppm, and the CH4:CO2 ratio, with a mean of 0.26 ± 0.05 ppb:ppm, are both higher than recent literature indicates. This is likely because our sampling distribution was biased towards cold vehicles, and therefore towards higher emission situations. The CH4:CO2 ratio was found to behave similarly to the CO:CO2 ratio, suggesting that the processes affecting CO and CH4 are similar. The δ13 C values in CO2 were close to the expected δ13 C in fuel, with no significant difference between petrol and diesel vehicles. The δ18 O values in CO2 for petrol vehicles covered a range of 20-35‰, similar to the δ18 O of CO. The δ18 O values in CO2 for diesel vehicles were close to the δ18 O in atmospheric oxygen. A set of polluted atmospheric samples, taken near a highway and inside parking garages, showed an isotopic signature of CO and a H2:CO ratio that were similar the high emitters in the individual vehicle measurements, with no significant differences between parking garage and highway samples. This suggests that in both environments, which are dominated by different driving conditions, the CO emissions from high emitters (either a few high emission vehicles, or many vehicles with brief bursts of high emissions) dominate the total traffic emissions.

Antibacterial activity of Artocarpus heterophyllus.

PubMed

Khan, M R; Omoloso, A D; Kihara, M

2003-07-01

The crude methanolic extracts of the stem and root barks, stem and root heart-wood, leaves, fruits and seeds of Artocarpus heterophyllus and their subsequent partitioning with petrol, dichloromethane, ethyl acetate and butanol gave fractions that exhibited a broad spectrum of antibacterial activity. The butanol fractions of the root bark and fruits were found to be the most active. None of the fractions were active against the fungi tested.

Defense Against Threat. Threat Recognition and Analysis Project

DTIC Science & Technology

1975-09-01

but clustering around it ( land affecting it) are other action structures of different character, now entering strongly on the world scene...seeks .o cap ur ^^’^^try to gestalts of cognition and affect , ^[Jj^ f c!anrPr or country, that put the signature of...TRAMSPORT 8, PETROL PRODUCTS 7.*, USR 27, JAP 18, IND Ik, - FRUITS +NUTS Ik, NATURAL GAS 17, LAMBSKINS 12, USR 30, PAK

Influence of test fuel properties and composition on UNECE R101 CO2 and fuel economy valuation

NASA Astrophysics Data System (ADS)

Parker, A.

2015-12-01

CO2 emission and fuel consumption of passenger cars is now assessed by using a simplistic procedure measuring the emission during a test performed without any control of the fuel properties and computing the fuel consumption through an unsophisticated formula. As pump gasoline and diesel fuels are refinery products mixture of many different hydrocarbons, and in case of gasoline may also contain a significant amount of oxygenates, the fuel properties, including the density, carbon and energy content may strongly vary from one pump fuel to the other. Being the specific test fuels carefully selected by the car manufacturers and everything but randomly chosen pump fuels, the claimed CO2 emission and fuel economy figures may differ largely from the certification values. I show from the analysis of the 2014 UK government data for 2358 diesel and 2103 petrol vehicles how same volumes of only theoretically same pump fuels used during the certification test by the cars manufacturers unfortunately do not produce the same carbon dioxide emission, and very likely do not have the same energy content. The CO2 emission per liter of diesel fuel is shown to oscillate froma maximum of 3049 g to a minimum of 2125 g, with an average of 2625 g, froma +16.13% to a -19.06% of the average. TheCO2 emission per liter of petrol fuel is shown to oscillate even more from a maximum of 3735 g to a minimum of 1767 g with an average of 2327 g, from a +60.48% to a -24.05% of the average. The proposed solution is to center the assessment on the energy demand by measuring with accuracy the mass of fuel consumed and the fuel properties of the test fuel starting from the lower heating. The corrected fuel consumption and the corrected carbon dioxide emission to mention from the test are then computed by using pure hydrocarbon reference fuels for diesel and petrol having a given lower heating value and a given hydrocarbon composition. Alternatively, exactly the same test fuel should be used by all the manufacturers.

New insights from comprehensive on-road measurements of NOx, NO2 and NH3 from vehicle emission remote sensing in London, UK

NASA Astrophysics Data System (ADS)

Carslaw, David C.; Rhys-Tyler, Glyn

2013-12-01

In this paper we report the first direct measurements of nitrogen dioxide (NO2) in the UK using a vehicle emission remote sensing technique. Measurements of NO, NO2 and ammonia (NH3) from almost 70,000 vehicles were made spanning vehicle model years from 1985 to 2012. These measurements were carefully matched with detailed vehicle information data to understand the emission characteristics of a wide range of vehicles in a detailed way. Overall it is found that only petrol fuelled vehicles have shown an appreciable reduction in total NOx emissions over the past 15-20 years. Emissions of NOx from diesel vehicles, including those with after-treatment systems designed to reduce emissions of NOx, have not reduced over the same period of time. It is also evident that the vehicle manufacturer has a strong influence on emissions of NO2 for Euro 4/5 diesel cars and urban buses. Smaller-engined Euro 4/5 diesel cars are also shown to emit less NO2 than larger-engined vehicles. It is shown that NOx emissions from urban buses fitted with Selective Catalytic Reduction (SCR) are comparable to those using Exhaust Gas Recirculation for Euro V vehicles, while reductions in NOx of about 30% are observed for Euro IV and EEV vehicles. However, the emissions of NO2 vary widely dependent on the bus technology used. Almost all the NOx emission from Euro IV buses with SCR is in the form of NO, whereas EEV vehicles (Enhanced Environmentally friendly Vehicle) emit about 30% of the NOx as NO2. We find similarly low amounts of NO2 from trucks (3.5-12t and >12t). Finally, we show that NH3 emissions are most important for older generation catalyst-equipped petrol vehicles and SCR-equipped buses. The NH3 emissions from petrol cars have decreased by over a factor of three from the vehicles manufactured in the late 1990s compared with those manufactured in 2012. Tables of emission factors are presented for NOx, NO2 and NH3 together with uncertainties to assist the development of new emission inventories.

Adverse mental health effects of cannabis use in two indigenous communities in Arnhem Land, Northern Territory, Australia: exploratory study.

PubMed

Clough, Alan R; d'Abbs, Peter; Cairney, Sheree; Gray, Dennis; Maruff, Paul; Parker, Robert; O'Reilly, Bridie

2005-07-01

We investigated adverse mental health effects and their associations with levels of cannabis use among indigenous Australian cannabis users in remote communities in the Northern Territory. Local indigenous health workers and key informants assisted in developing 28 criteria describing mental health symptoms. Five symptom clusters were identified using cluster analysis of data compiled from interviews with 103 cannabis users. Agreement was assessed (method comparison approach, kappa-statistic) with a clinician's classification of the 28 criteria into five groups labelled: 'anxiety', 'dependency', 'mood', 'vegetative' and 'psychosis'. Participants were described as showing 'anxiety', 'dependency' etc., if they reported half or more of the symptoms comprising the cluster. Associations between participants' self-reported cannabis use and each symptom cluster were assessed (logistic regression adjusting for age, sex, other substance use). Agreement between two classifications of 28 criteria into five groups was 'moderate' (64%, kappa = 0.55, p < 0.001). When five clusters were combined into three, 'anxiety-dependency', 'mood-vegetative' and 'psychosis', agreement rose to 71% (kappa = 0.56, p < 0.001). 'Anxiety-dependency' was positively associated with number of 'cones' usually smoked per week and this remained significant when adjusted for confounders (p = 0.020) and tended to remain significant in those who had never sniffed petrol (p = 0.052). Users of more than five cones per week were more likely to display 'anxiety-dependency' symptoms than those who used one cone per week (OR = 15.8, 1.8-141.2, p = 0.013). A crude association between the 'mood-vegetative' symptom cluster and number of cones usually smoked per week (p = 0.014) also remained statistically significant when adjusted for confounders (p = 0.012) but was modified by interactions with petrol sniffing (p = 0.116) and alcohol use (p = 0.276). There were no associations between cannabis use and 'psychosis'. Risks for 'anxiety-dependency' symptoms in cannabis users increased as their level of use increased. Other plausible mental health effects of cannabis in this population of comparatively new users were probably masked by alcohol use and a history of petrol sniffing.

The Applicability of Patented Technologies to Sonobuoys

DTIC Science & Technology

1988-06-30

Ave, Boulder, CO 80301 2. Compagnie Generale de Geophysique 6 Rue Galvani Paris, France 3. EIC Laboratories, Incorporated Newton, MA 02146 4. Edo...Co. 2 Compagnie de Geophysique , France 3 Cooper, Charles E. 2 M Crown Controls Corporation 1 ,6 Cyr, Reginald J. 1 DeltaLab Research, Incorporated 1...Int’l App ....... 7,5 [73) Assignees: Institut Francais du Petrole. OTHER PUBLICATIONS -" Rueil-Malmaison; Compagnie Generale de Geophysique , Massy

The Development of British Incendiary Bombs during the Period of the 1939-45 World War

DTIC Science & Technology

1946-12-01

gallons of methanised petrol and had a T.V. of 160 - 180 ft./sec., when falling suspended from its parasheet. 21.2 In the early stages of the design it...34J" lomb Mark I, filled with methanised shale spirit. 80 July ORD Note summari3ing American developments with the M69 bomb. 81 " 7RS Report on Tests

Modern steels for light automobiles (review)

NASA Astrophysics Data System (ADS)

Tikhonov, A. K.

1994-10-01

The article considers the directions of work at VAZ together with metallurgists of the CIS for creating highly efficient economically-alloyed and microalloyed steels; highly ductile forged steels with improved corrosion resistance coated with zinc and with good stamping, welding, and painting capacity. Steels are created for petrol tanks with aluminum-zinc coatings instead of lead, and new heat and corrosion-resistant steels are developed for automobile exhaust gas systems.

Effect of deregulation on the prices of nicotine replacement therapy products in Finland.

PubMed

Aalto-Setälä, Ville; Alaranta, Antti

2008-05-01

The sales of nicotine replacement therapy (NRT) products were deregulated in Finland in February 2006. Previously all medications were sold only in pharmacies, and retail mark-ups and prices were fixed; following deregulation pricing of NRT products has been free. Further more, grocery shops, petrol stations and kiosks are now licensed to sell NRT products. The objective of this study is to evaluate the impact of deregulation on prices of NRT products. We utilized price data on NRT products (n=2106) from pharmacies, grocery shops, kiosks and petrol stations. Market prices are compared with former regulated prices, as are the prices at different types of outlets. We examined the relationship between competition and prices by regression analysis. The average price of NRT products decreased 15% after deregulation. About half of the price decrease was due to exemption of NRT products from the pharmacy fee as part of deregulation, and the other half to increased competition. The least expensive NRT products are obtainable in hypermarkets; however, pharmacies have the largest variety. Deregulation of NRT products in Finland was successful in that the prices of these products have decreased and their availability increased. Based on international experience, however, it is not clear whether these decreased prices and increased availabilities have increased smoking cessation.

Generation of oxy-hydrogen gas and its effect on performance of spark ignition engine

NASA Astrophysics Data System (ADS)

Patil, N. N.; Chavan, C. B.; More, A. S.; Baskar, P.

2017-11-01

Considering the current scenario of petroleum fuels, it has been observed that, they will last for few years from now. On the other hand, the ever increasing cost of a gasoline fuels and their related adverse effects on environment caught the attention of researchers to find a supplementary source. For commercial fuels, supplementary source is not about replacing the entire fuel, instead enhancing efficiency by simply making use of it in lesser amount. From the recent research that has been carried out, focus on the use of Hydrogen rich gas as a supplementary source of fuel has increased. But the problem related to the storage of hydrogen gas confines the application of pure hydrogen in petrol engine. Using oxy-hydrogen gas (HHO) generator the difficulties of storing the hydrogen have overcome up to a certain limit. The present study highlights on performance evaluation of conventional petrol engine by using HHO gas as a supplementary fuel. HHO gas was generated from the electrolysis of water. KOH solution of 3 Molar concentration was used which act as a catalyst and accelerates the rate of generation of HHO gas. Quantity of gas to be supplied to the engine was controlled by varying amount of current. It was observed that, engine performance was improved on the introduction of HHO gas.

Lead isotope ratios in tree bark pockets: an indicator of past air pollution in the Czech Republic.

PubMed

Conkova, M; Kubiznakova, J

2008-10-15

Tree bark pockets were collected at four sites in the Czech Republic with differing levels of lead (Pb) pollution. The samples, spanning 1923-2005, were separated from beech (Fagus sylvatica) and spruce (Picea abies). Elevated Pb content (0.1-42.4 microg g(-1)) reflected air pollution in the city of Prague. The lowest Pb content (0.3-2.6 microg g(-1)) was found at the Kosetice EMEP "background pollution" site. Changes in (206)Pb/(207)Pb and (208)Pb/(206)Pb isotope ratios were in agreement with operation times of the Czech main anthropogenic Pb sources. Shortly after the Second World War, the (206)Pb/(207)Pb isotope ratio in bark pockets decreased from 1.17 to 1.14 and the (208)Pb/(206)Pb isotope ratio increased from 2.12 to 2.16. Two dominant emission sources responsible for these changes, lignite and leaded petrol combustion, contributed to the shifts in Pb isotope ratios. Low-radiogenic petrol Pb ((206)Pb/(207)Pb of 1.11) lead to lower (206)Pb/(207)Pb in bark pockets over time. High-radiogenic lignite-derived Pb ((206)Pb/(207)Pb of 1.18 to 1.19) was detected in areas affected by coal combustion rather than by traffic.

A case of acute gasoline intoxication at the scene of washing a petrol tank.

PubMed

Takamiya, Masataka; Niitsu, Hisae; Saigusa, Kiyoshi; Kanetake, Jun; Aoki, Yasuhiro

2003-09-01

We encountered a case of acute gasoline intoxication at the scene of washing the inner wall of a petrol tank. The decedent was a 50-year-old male, who was the supervisor. Two young workers wearing mask respirators began to wash the inner wall of the gasoline tank under poor ventilation. About 1 h later, because one of the workers lost consciousness, the supervisor entered the tank, without a mask respirator, to rescue the worker. However, the supervisor immediately fainted, and died 26 h after the accident. In the autopsy, blisters were observed on the skin of the face, neck, anterior chest, upper extremities, and back. The heart contained hemolyzed blood. Histologically, hemorrhagic pulmonary edema, pneumonia, and proximal tubular necrosis were found. In the toxicological analyzes, toluene, xylene, and trimethylbenzene were detected in the blood, brain, and gastric contents. Toluene concentrations in the blood and brain were 0.3 mug/ml and 3.7 mug/g, respectively. Since pathological findings were consistent with the reported findings concerning gasoline intoxication, and constituents of gasoline were in the body, death was attributed to acute gasoline intoxication. It was considered that sufficient ventilation and proper use of a mask respirator were essential for this kind of work.

Did the elimination of lead from petrol reduce crime in the USA in the 1990s?

PubMed Central

Hall, Wayne

2013-01-01

This article assesses the evidence for the hypothesis that a decline in all types of crime since the early 1990s in the USA was a consequence of removing lead from petrol between 1975 and 1985. It describes ecological and econometric studies that have generally but not always found correlations between lead exposures in childhood and some types of crime 20 years later; a small number of epidemiological studies that have found a dose-response relationship between lead exposure in childhood and self-reported and officially recorded criminal offences in young adulthood; and evidence for the biological plausibility of a causal relationship. Lead exposure in childhood may have played a small role in rising and falling crime rates in the USA but it is unlikely to account for the very high percentage of the decline suggested by the ecological studies. The major anomaly in the evidence is that the associations reported in ecological studies are much stronger (explaining 56-90% of the variation in crime rates) than the weaker relationships found in the cohort studies (that typically explain less than 1% of the variance in offending).  Suggestions are made for research that will better assess the contribution that reduced lead exposure has made to declining crime rates in the USA. PMID:24555074

Significant locations in auxiliary data as seeds for typical use cases of point clustering

NASA Astrophysics Data System (ADS)

Kröger, Johannes

2018-05-01

Random greedy clustering and grid-based clustering are highly susceptible by their initial parameters. When used for point data clustering in maps they often change the apparent distribution of the underlying data. We propose a process that uses precomputed weighted seed points for the initialization of clusters, for example from local maxima in population density data. Exemplary results from the clustering of a dataset of petrol stations are presented.

Flavonoids from Lonchocarpus latifolius roots.

PubMed

Magalhães, A F; Tozzi, A M; Magalhães, E G; Nogueira, M A; Queiroz, S C

2000-12-01

From the petrol extract of Lonchocarpus latifolius roots, 10 flavonoids were isolated. These included: 3,5-dimethoxy-2'',2''-dimethylpyrano-(5'',6'':8,7)-flavone, 3-methoxy-(2'',3'':7,8)-furanoflavanone, 3',4'-methylenedioxy-(2'',3'':7,8)-furanoflavanone, and (2,3-trans-3,4-trans)-3,4-dimethoxy-(2'',3'':7,8)-furanoflavan, as well as the previously known karanjachromene, karanjin, lanceolatin B, pongachromene, pongaglabrone and ponganpin. Only nine flavonoids could be quantified through HPLC analysis.

Africa and the Arab Spring: A New Era of Democratic Expectations

DTIC Science & Technology

2011-11-01

legislatures approve major aid packages (from the World Bank or Millennium Challenge Corporation , for example) as well as contracts with resource extraction...Moreover, Libyan businesses and finance institutions closely aligned with the Gaddafi regime had invested billions of dollars in hotels, banks , petrol...DC: The World Bank , 2011); UNESCO Institute for Statistics, 2011. 52 “Lions on the Move: The Progress and Potential of Africa’s Economies,” McKinsey

A new statistical analysis of rare earth element diffusion data in garnet

NASA Astrophysics Data System (ADS)

Chu, X.; Ague, J. J.

2015-12-01

The incorporation of rare earth elements (REE) in garnet, Sm and Lu in particular, links garnet chemical zoning to absolute age determinations. The application of REE-based geochronology depends critically on the diffusion behaviors of the parent and daughter isotopes. Previous experimental studies on REE diffusion in garnet, however, exhibit significant discrepancies that impact interpretations of garnet Sm/Nd and Lu/Hf ages.We present a new statistical framework to analyze diffusion data for REE using an Arrhenius relationship that accounts for oxygen fugacity, cation radius and garnet unit-cell dimensions [1]. Our approach is based on Bayesian statistics and is implemented by the Markov chain Monte Carlo method. A similar approach has been recently applied to model diffusion of divalent cations in garnet [2]. The analysis incorporates recent data [3] in addition to the data compilation in ref. [1]. We also include the inter-run bias that helps reconcile the discrepancies among data sets. This additional term estimates the reproducibility and other experimental variabilities not explicitly incorporated in the Arrhenius relationship [2] (e.g., compositional dependence [3] and water content).The fitted Arrhenius relationships are consistent with the models in ref. [3], as well as refs. [1]&[4] at high temperatures. Down-temperature extrapolation leads to >0.5 order of magnitude faster diffusion coefficients than in refs. [1]&[4] at <750 °C. The predicted diffusion coefficients are significantly slower than ref. [5]. The fast diffusion [5] was supported by a field test of the Pikwitonei Granulite—the garnet Sm/Nd age postdates the metamorphic peak (750 °C) by ~30 Myr [6], suggesting considerable resetting of the Sm/Nd system during cooling. However, the Pikwitonei Granulite is a recently recognized UHT terrane with peak temperature exceeding 900 °C [7]. The revised closure temperature (~730 °C) is consistent with our new diffusion model.[1] Carlson (2012) Am Mineral 97 1598-1618. [2] Chu & Ague (2015) Contrib Mineral Petrol, in press. [3] Bloch et al. (2015) Contrib Mineral Petrol 169 1-18. [4] Van Orman et al. (2002) Contrib Mineral Petrol 142 416-424. [5] Tirone et al. (2005) GCA 69 2385-2398. [6] Mezger et al. (1992) EPSL 113 397-409. [7] Kooijman et al. (2012) J Metamorph Geol 30 397-412.

PGE and Re-Os Isotope Behaviour in a Subduction-Modified Mantle Wedge: A Fresh Look into the Peridotites from the Ulten Zone, Eastern Alps

NASA Astrophysics Data System (ADS)

Aulbach, S.; Braga, R.; Gudelius, D.; Prelevic, D.; Meisel, T. C.

2015-12-01

Peridotites in the upper Austroalpine Ulten zone (Eastern Italy) sample the subduction-modified Variscan mantle wedge. Metasomatism of peridotites during four stages of mantle wedge evolution includes: (1) Intrusion of alkaline melts from an inner, subduction-modified wedge and cryptic enrichment of spinel lherzolites (SL); (2) Reaction with siliceous crustal melts after pressure increase, generating coarse-grained garnet amphibole peridotites (GAP); (3) Crystallisation of abundant amphibole (± apatite and dolomite) from residual hydrous fluids during and/or after peak metamorphism recorded by fine-grained GAP; [4] Subsequent influx of crustal fluids, causing retrograde formation of spinel chlorite amphibole peridotites (SAP) [1-5]. SL and coarse GAP are apparently more fertile, whereas fine GAP and SAP retain the most depleted major-element characteristics. Overall, samples fall on partial melting trends consistent with extraction of low degrees of melt (F≤0.15) at 2-1 GPa. SL and coarse GAP have ±flat PGE patterns normalised to Primitive Upper Mantle (PUM), or show small decreases or increases from compatible to incompatible PGE. This suggests retention of primary sulphide liquid at low degrees of melting, during which PGE concentrations are little fractionated [6]. Indeed, broad positive correlations between the PGE suggest a common host, likely sulphide, observed in the samples as assemblages of pn ± po and cpy. Most fine-GAP share these patterns, indicating robustness against massive hydrous fluid influx, while Os/Ir > PUM argue against strong Os scavenging by highly oxidising hydrous fluids. Nevertheless, elevated Ru/IrPUM in a subgroup of samples may indicate a role for spinel addition under oxidising conditions. Most samples have 187Os/188Os >PUM, despite sub-PUM Re/Os, which requires addition of, or isotopic equilibration with, 187Os-rich crustal components, most likely via the precipitation of metasomatic sulphide. [1] Nimis and Morten (2000) J Geodyn 30: 93-115; [2] Rampone and Morten (2001) J Petrol 42: 207-219; [3] Tumiati et al. (2003) Earth Planet Sci Lett 210: 509-526; [4] Sapienza et al. (2009) Contrib Mineral Petrol 158: 401-420; [5] Scambelluri et al. (2006) Contrib Mineral Petrol 151: 372-394; [6] Mungall and Brenan (2014) Geochim Cosmochim Acta 125: 265-289.

Techno-economic comparison of series hybrid, plug-in hybrid, fuel cell and regular cars

NASA Astrophysics Data System (ADS)

van Vliet, Oscar P. R.; Kruithof, Thomas; Turkenburg, Wim C.; Faaij, André P. C.

We examine the competitiveness of series hybrid compared to fuel cell, parallel hybrid, and regular cars. We use public domain data to determine efficiency, fuel consumption, total costs of ownership and greenhouse gas emissions resulting from drivetrain choices. The series hybrid drivetrain can be seen both as an alternative to petrol, diesel and parallel hybrid cars, as well as an intermediate stage towards fully electric or fuel cell cars. We calculate the fuel consumption and costs of four diesel-fuelled series hybrid, four plug-in hybrid and four fuel cell car configurations, and compared these to three reference cars. We find that series hybrid cars may reduce fuel consumption by 34-47%, but cost €5000-12,000 more. Well-to-wheel greenhouse gas emissions may be reduced to 89-103 g CO 2 km -1 compared to reference petrol (163 g km -1) and diesel cars (156 g km -1). Series hybrid cars with wheel motors have lower weight and 7-21% lower fuel consumption than those with central electric motors. The fuel cell car remains uncompetitive even if production costs of fuel cells come down by 90%. Plug-in hybrid cars are competitive when driving large distances on electricity, and/or if cost of batteries come down substantially. Well-to-wheel greenhouse gas emissions may be reduced to 60-69 g CO 2 km -1.

Automatic extraction of property norm-like data from large text corpora.

PubMed

Kelly, Colin; Devereux, Barry; Korhonen, Anna

2014-01-01

Traditional methods for deriving property-based representations of concepts from text have focused on either extracting only a subset of possible relation types, such as hyponymy/hypernymy (e.g., car is-a vehicle) or meronymy/metonymy (e.g., car has wheels), or unspecified relations (e.g., car--petrol). We propose a system for the challenging task of automatic, large-scale acquisition of unconstrained, human-like property norms from large text corpora, and discuss the theoretical implications of such a system. We employ syntactic, semantic, and encyclopedic information to guide our extraction, yielding concept-relation-feature triples (e.g., car be fast, car require petrol, car cause pollution), which approximate property-based conceptual representations. Our novel method extracts candidate triples from parsed corpora (Wikipedia and the British National Corpus) using syntactically and grammatically motivated rules, then reweights triples with a linear combination of their frequency and four statistical metrics. We assess our system output in three ways: lexical comparison with norms derived from human-generated property norm data, direct evaluation by four human judges, and a semantic distance comparison with both WordNet similarity data and human-judged concept similarity ratings. Our system offers a viable and performant method of plausible triple extraction: Our lexical comparison shows comparable performance to the current state-of-the-art, while subsequent evaluations exhibit the human-like character of our generated properties.

Contamination and UV ageing of diffuser targets used in satellite inflight and ground reference test site calibrations

NASA Astrophysics Data System (ADS)

Vaskuri, Anna; Greenwell, Claire; Hessey, Isabel; Tompkins, Jordan; Woolliams, Emma

2018-02-01

Diffuser reflectance targets are key components in in-orbit calibrations and for verifying ground reference test sites. In this work, Spectralon, Diffusil, and Heraeus diffusers were exposed to exhaust gases and ultraviolet (UV) radiation in the ambient air conditions and their degradations were monitored by measuring changes in spectral reflectances. Spectralon is a state-of-the-art diffuser made of polytetrafluoroethylene, and Diffusil and Heraeus diffusers are made of fused silica with gas bubbles inside. Based on the contamination tests, Spectralon degrades faster than fused silica diffusers. For the samples exposed to contamination for 20 minutes, the 250 nm - 400 nm total diffuse spectral reflectance of Spectralon degraded 3-5 times more when exposed to petrol-like emission and 16-23 times more when exposed to diesel-like emission, compared with Diffusil. When the reflectance changes of Spectralon were compared with those of Heraeus, Spectralon degraded 3-4 times more when exposed to petrol-like emission for 20 minutes and 5-7 times more when exposed to diesel-like emission for 7.5 minutes. When the samples contaminated were exposed to UV radiation in the ambient air, their reflectance gradually restored back to the original level. In conclusion, fused silica diffusers are more resistant to hydrocarbon contaminants present in ground reference test sites, and thus more stable under UV radiation in the air.

Updating about reductions of air and blood lead concentrations in Turin, Italy, following reductions in the lead content of gasoline.

PubMed

Bono, R; Pignata, C; Scursatone, E; Rovere, R; Natale, P; Gilli, G

1995-07-01

Considering its well-know toxicity and the chronic human exposure to lead, international law-makers enforced some directives or laws calling for the reduction of lead content of gasoline. All of these legislative acts aimed to reduce health risks for the general population. The aim of this study was to consider the effectiveness of these laws on air lead levels and consequently on blood lead levels in a randomly selected urban Italian population. In particular, these markers were analyzed over the course of several years, corresponding to the periods just before and after enforcements of the reductions of lead in petrol. Data presented point out some considerations: (1) enforcement of legislative measures concerning the reduction of lead in petrol has reduced atmospheric levels of lead. This result demonstrates a major environmental success in primary prevention efforts. (2) This success is clear especially considering that the actual Pb-B levels can be extended to the urbanized populations. Pb-B levels were consistently higher for drinkers, for older adults, and for males. The mean of Pb-B level for the present urbanized population is higher than the U.S. overall population (6.4 vs 3 microgram/dl). This difference can be also explained considering the different historical period of enforcement of the restriction laws.

Design and modelling of high gain DC-DC converters for fuel cell hybrid electric vehicles

NASA Astrophysics Data System (ADS)

Elangovan, D.; Karthigeyan, V.; Subhanu, B.; Ashwin, M.; Arunkumar, G.

2017-11-01

Transportation (Diesel and petrol internal combustion engine vehicles) approximately contributes to 25.5% of total CO2 emission. Thus diesel and petrol engine vehicles are the most dominant contributors of CO2 emission which leads global warming which causes climate change. The problem of CO2 emission and global warming can be reduced by focusing on renewable energy vehicles. Out of the available renewable energy sources fuel cell is the only source which has reasonable efficiency and can be used in vehicles. But the main disadvantage of fuel cell is its slow response time. So energy storage systems like batteries and super capacitors are used in parallel with the fuel cell. Fuel cell is used during steady state vehicle operation while during transient conditions like starting, acceleration and braking batteries and super capacitors can supply or absorb energy. In this paper a unidirectional fuel cell DC-DC converter and bidirectional energy storage system DC-DC converter is proposed, which can interface dc sources at different voltage levels to the dc bus and also it can independently control the power flow from each energy source to the dc bus and vice versa. The proposed converters are designed and simulated using PSIM version 9.1.1 and gate pulse pattern, input and output voltage waveforms of the converters for steady state operation are studied.

Determining exhaust fumes exposure in chainsaw operations.

PubMed

Neri, F; Foderi, C; Laschi, A; Fabiano, F; Cambi, M; Sciarra, G; Aprea, M C; Cenni, A; Marchi, E

2016-11-01

The objective of this study was to investigate the inhalation exposure of forest operators to polycyclic aromatic hydrocarbons (PAHs) and BTEX (benzene, toluene, ethylbenzene and total xylenes) contained in the exhaust fumes released from chainsaws and to suggest possible countermeasures. The study was carried out in four silvicultural treatments (coppice clearcut, conifer thinning, conifer pruning, and sanitary cut), using three types of chainsaw fuel (normal two-stroke petrol mix and two alkylate fuels). Eighty personal air samples were collected; IOM samplers combined with Amberlite XAD-2 sorbent tubes were used for collecting PAHs and Radiello ® samplers were used for BTEX. Results indicate that none of the four silvicultural treatments significantly affected the PAHs and BTEX inhalation exposure of forest workers. On the other hand, statistically significant differences were recorded in the inhalation exposure to PAHs and BTEX when using different fuel types. In particular, the inhalation exposure to PAHs and BTEX was generally one order of magnitude lower when using modern alkylate fuels as compared to the traditional oil and lead-free petrol mixture. The small, non-statistically significant differences in inhalation exposure recorded between the two alkylate fuels suggests that the two fuels might be equivalent in terms of quality. Our study indicates that while forest workers are exposed to PAHs and BTEX, the maximum values are generally well below accepted occupational exposure limits. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ready Reserve Civilian Skills Utilization Study (RESCON).

DTIC Science & Technology

1975-11-10

brokers, insurance, business, etc.) 6 Special Skills/Talents 7 Pilots 10 Engineers, Industrial 10 Petrol & Chem 10 Aero 11 EE 12 19 Civil 13- Math ...AD-A123 132 READY RESERVE CIVILIAN SKILLS UTILIZATION STUDY (RESCON)(U) MARINE CORPS VTU 12 -3 NAS MOFFETT FIELD CA E O AGEE ET ALS 10 NOV 75...Nov 7! ?-~1UTILIZATION STUDY (RESCON) 6. PEaRORMING OR011. REPORT MNMER VTU 12 -3 0/F 1. AUTNOR(#) CoB CONTRACT ON GRANT MUMMER(@) Lto R. J. to~r C

ISM (Industrial Scientific and Medical standard) band flex fuel sensor using electrical metamaterial device

NASA Astrophysics Data System (ADS)

Rawat, Vaishali; Nadkarni, Vihang; Kale, S. N.

2017-01-01

A stand-alone device working on the electrical metamaterial concept, operating at 2.47 GHz (ISM band), using merely 10 μL sample is proposed to detect petrol/ethanol ratio in given hybrid fuel. Systematic shifts in the transmission frequency as well as magnitude are observed, up to a maximum of 160 MHz and 12 dBm with the hybrid fuels. The sensing was fast with an instantaneous recovery, promising an accurate and sensitive device of detection of flex fuel.

Proceedings of a Workshop on the Physical Properties of Volcanic Seafloor, Held at Woods Hole, Massachusetts on April 24-26, 1990

DTIC Science & Technology

1990-04-26

peridotites, J. Petrol., 27, 999-1022. Peterson, D.W. and Tilling, R.I., 1980, Transition of basaltic lava from pahoehoe to aa, Kilauea Volcano , Hawaii : Field...Oceanographic Institution and G.J. Fryer of the University of Hawaii . Guidance in the planning and execution of the workshop was provided by a steering...sample recovery provided by ophiolite formations, subareal volcanic systems (e.g., Hawaii , Iceland) and major seafloor scarps (’windows’ into the crust

Triacetonide of Glucoheptonic Acid in the Scalable Syntheses of d-Gulose, 6-Deoxy-d-gulose, l-Glucose, 6-Deoxy-l-glucose, and Related Sugars.

PubMed

Liu, Zilei; Yoshihara, Akihide; Jenkinson, Sarah F; Wormald, Mark R; Estévez, Ramón J; Fleet, George W J; Izumori, Ken

2016-08-19

Ease of separation of petrol-soluble acetonides derived from the triacetonide of methyl glucoheptonate allows scalable syntheses of rare sugars containing the l-gluco or d-gulo structural motif with any oxidation level at the C6 or C1 position of the hexose, usually without chromatography: meso-d-glycero-d-guloheptitol available in two steps is an ideal entry point for the study of the biotechnological production of heptoses.

Escaping America’s Future: A Clarion Call for a National Energy Security Strategy

DTIC Science & Technology

2010-06-01

the heavy oils, the air by means of the ultra refined oils, and the land by means of the petrol and the illuminating oils. And in addition to these he... Deepwater Horizon oil spill incident in the Gulf, although classified an accident, demonstrates how damaging a potential attack on infrastructure could...energy, but has suffered recent setbacks due to the Deepwater Horizon oil spill in the Gulf of Mexico. The Outer Continental Shelf surrounding the

Great Power Interests and Conflicting Objectives in the Mediterranean-Middle East-Persian Gulf Region. Part I. Background Studies.

DTIC Science & Technology

1974-12-01

Tunisia , and Algeria; between Italy and 1ibya; and between Britain and Egypt, Jordan, Iraq, and the Persia.i Gulf. The British now have little more... Petrole : la troisieme guerre mondiale, pp. 215 ff (Paris, 1974) 56 All this adds up to a mixed bag of conceptual and structural differences which is...signed an agree- ment with Morocco (for two patrol vessels) and Tunisia (one patrol vessel) and expanded its arms deals with Libya. Germany and Italy

The North Atlantic Treaty Organization and Libya: Reviewing Operation Unified Protector

DTIC Science & Technology

2013-06-01

Qaddafi appeared on state TV. He de- clared he was “in pain” about the removal of Tunisia President Ben Ali, and described the demonstrators as “led...only be- cause of large petrol resources but also the existence of maritime choke points and one of the most important world trade routes, it attracts... Tunisia Uprising,” The Guardian, January 16, 2011, available from www.guardian.co.uk/ world/2011/jan/16/muammar-gaddafi-condemns- tunisia -uprising

Characterization of on-road CO, HC and NO emissions for petrol vehicle fleet in China city*

PubMed Central

Guo, Hui; Zhang, Qing-yu; Shi, Yao; Wang, Da-hui; Ding, Shu-ying; Yan, Sha-sha

2006-01-01

Vehicle emissions are a major source of air pollution in urban areas. The impact on urban air quality could be reduced if the trends of vehicle emissions are well understood. In the present study, the real-world emissions of vehicles were measured using a remote sensing system at five sites in Hangzhou, China from February 2004 to August 2005. More than 48000 valid gasoline powered vehicle emissions of carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxide (NO) were measured. The results show that petrol vehicle fleet in Hangzhou has considerably high CO emissions, with the average emission concentration of 2.71%±0.02%, while HC and NO emissions are relatively lower, with the average emission concentration of (153.72±1.16)×10−6 and (233.53±1.80)×10−6, respectively. Quintile analysis of both average emission concentration and total amount emissions by model year suggests that in-use emission differences between well maintained and badly maintained vehicles are larger than the age-dependent deterioration of emissions. In addition, relatively new high polluting vehicles are the greatest contributors to fleet emissions with, for example, 46.55% of carbon monoxide fleet emissions being produced by the top quintile high emitting vehicles from model years 2000~2004. Therefore, fleet emissions could be significantly reduced if new highly polluting vehicles were subject to effective emissions testing followed by appropriate remedial action. PMID:16773726

The determination of residence times in a pilot plant

NASA Astrophysics Data System (ADS)

Ramírez, F. Pablo; Cortés, M. Eugenia

2004-01-01

It is well known that residence time distributions (RTD) are very important in many chemical processes such as separation, reforming, hydrocracking, fluid catalytic cracking, hydrodesulfuration, hydrogenation among others [3 Procédés de transformation, Editions Technip, Institute Francais du Petrole, Paris, France, 1998]. In addition, tracers can be used to measure the velocity, distribution and residence time of any stream through any part of an industrial [Guidebook on Radioisotope Tracers in Industry, IAEA, Vienna, 1990] or experimental system. Perhaps the best quality of radiotracers is that they do not interfere with normal unit operations or production scheduling. In this paper are presented the RTDs obtained in a pilot plant for a hydrogenation process [IMP, Technical Report, Determinación del tiempo de residencia promedio en el reactor de la planta piloto de hidroagotamiento de crudo, 2002]. The RTDs show a random phenomenon, which is not typical of this type of chemical processes. Several RTDs were determined in order to confirm this random behavior. The data were obtained using as a tracer a radioactive form of sodium iodide containing iodine-131 [The Condensed Chemical Dictionary, 10th Ed., Van Nostrand Reinhold, USA, 1981]. The process works with two phases in a countercurrent flow, inside a packed column. The liquid phase goes down by gravity. The gas phase goes up due to pressure difference [3 Procédés de transformation, Editions Technip, Institute Francais du Petrole, Paris, France, 1998]. The tracer was selected such that it would follow the liquid phase.

Lead concentrations and isotope ratios in street dust determined by electrothermal atomic absorption spectrometry and inductively coupled plasma mass spectrometry.

PubMed

Nageotte, S M; Day, J P

1998-01-01

A major source of environmental lead, particularly in urban areas, has been from the combustion of leaded petrol. Street dust has previously been used to assess urban lead contamination, and the dust itself can also be a potential source of lead ingestion, particularly to children. The progressive reduction of lead in petrol, in recent years, would be expected to have been reflected in a reduction of lead in urban dust. We have tested this hypothesis by repeating an earlier survey of Manchester street dust and carrying out a comparable survey in Paris. Samples were collected from streets and parks, lead was extracted by digestion with concentrated nitric acid and determined by electrothermal atomic absorption spectrometry. Lead isotope ratios were measured by inductively coupled plasma mass spectrometry. Results for Manchester show that lead concentrations have fallen by about 40% (street dust averages, 941 micrograms g-1 (ppm) in 1975 down to 569 ppm in 1997). In Paris, the lead levels in street dust are much higher and significant differences were observed between types of street (not seen in Manchester). Additionally, lead levels in parks were much lower than in Manchester. Samples collected under the Eiffel Tower had very high concentrations and lead isotope ratios showed that this was unlikely to be fallout from motor vehicles but could be due to the paint used on the tower. Isotope ratios measurements also revealed that lead additives used in France and the UK come from different sources.

Whey-derived valuable products obtained by microbial fermentation.

PubMed

Pescuma, Micaela; de Valdez, Graciela Font; Mozzi, Fernanda

2015-08-01

Whey, the main by-product of the cheese industry, is considered as an important pollutant due to its high chemical and biological oxygen demand. Whey, often considered as waste, has high nutritional value and can be used to obtain value-added products, although some of them need expensive enzymatic synthesis. An economical alternative to transform whey into valuable products is through bacterial or yeast fermentations and by accumulation during algae growth. Fermentative processes can be applied either to produce individual compounds or to formulate new foods and beverages. In the first case, a considerable amount of research has been directed to obtain biofuels able to replace those derived from petrol. In addition, the possibility of replacing petrol-derived plastics by biodegradable polymers synthesized during bacterial fermentation of whey has been sought. Further, the ability of different organisms to produce metabolites commonly used in the food and pharmaceutical industries (i.e., lactic acid, lactobionic acid, polysaccharides, etc.) using whey as growth substrate has been studied. On the other hand, new low-cost functional whey-based foods and beverages leveraging the high nutritional quality of whey have been formulated, highlighting the health-promoting effects of fermented whey-derived products. This review aims to gather the multiple uses of whey as sustainable raw material for the production of individual compounds, foods, and beverages by microbial fermentation. This is the first work to give an overview on the microbial transformation of whey as raw material into a large repertoire of industrially relevant foods and products.

Oil fuel delivery optimization for multi product and multi depot: the case of petrol station replenishment problem (PSRP)

NASA Astrophysics Data System (ADS)

Surjandari, Isti; Rachman, Amar; Dianawati, Fauzia; Wibowo, R. Pramono

2011-10-01

With the Oil and Gas Law No. 22 of 2001, national and foreign private enterprises can invest in all sectors of Oil and Gas in Indonesia. In anticipation of this free competition, Pertamina, as a state-owned enterprises, which previously had monopolized the oil and gas business activities in Indonesia, should be able to improve services as well as the efficiency in order to compete in the free market, especially in terms of cost efficiency of fuel distribution to gas station (SPBU). To optimize the distribution activity, it is necessary to design a scheduling system and its fuel delivery routes daily to every SPBU. The determination of routes and scheduling delivery of fuel to the SPBU can be modeled as a Petrol Station Replenishment Problem (PSRP) with the multi-depot, multi-product, time windows and split deliveries, which in this study will be completed by the Tabu Search algorithm (TS). This study was conducted in the area of Bandung, the capital of West Java province, which is a big city and the neighboring city of Jakarta, the capital city of Indonesia. By using the fuel delivery data for one day, the results showed a decrease of 16.38% of the distance of the route compared to the current conditions, which impacted on the reduction of distribution costs and decrease the number of total trips by 5.22% and 3.83%.

Investigation of gasoline distributions within petrol stations: spatial and seasonal concentrations, sources, mitigation measures, and occupationally exposed symptoms.

PubMed

Sairat, Theerapong; Homwuttiwong, Sahalaph; Homwutthiwong, Kritsana; Ongwandee, Maneerat

2015-09-01

We measured levels of VOCs and determined the distributions of benzene concentrations over the area of two petrol stations in all three seasons. Using the concentrations and sampling positions, we created isoconcentration contour maps. The average concentrations ranged 18-1288 μg m(-3) for benzene and 12-81 μg m(-3) for toluene. The contour maps indicate that high-level contours of benzene were found not only at the fuel dispenser areas but also at the storage tank refilling points, open drainage areas where gasoline-polluted wastewater was flowing, and the auto service center located within the station area. An assessment of the benzene to toluene ratio contour plots implicates that airborne benzene and toluene near the fuel dispenser area were attributed to gasoline evaporation although one of the studied stations may be influenced by other VOC sources besides gasoline evaporation. Additionally, during the routine refilling of the underground fuel storage tanks by a tank truck, the ambient levels of benzene and toluene increased tremendously. The implementation of source control by replacing old dispensers with new fuel dispensers that have an efficient cutoff feature and increased delivery speed can reduce spatial benzene concentrations by 77%. Furthermore, a questionnaire survey among 63 service attendants in ten stations revealed that headache was the most reported health complaint with a response rate of 32%, followed by fatigue with 20%. These prominent symptoms could be related to an exposure to high benzene concentrations.

Biodegradability of commercial and weathered diesel oils

PubMed Central

Mariano, Adriano Pinto; Bonotto, Daniel Marcos; de Franceschi de Angelis, Dejanira; Pirôllo, Maria Paula Santos; Contiero, Jonas

2008-01-01

This work aimed to evaluate the capability of different microorganisms to degrade commercial diesel oil in comparison to a weathered diesel oil collected from the groundwater at a petrol station. Two microbiological methods were used for the biodegradability assessment: the technique based on the redox indicator 2,6 -dichlorophenol indophenol (DCPIP) and soil respirometric experiments using biometer flasks. In the former we tested the bacterial cultures Staphylococcus hominis, Kocuria palustris, Pseudomonas aeruginosa LBI, Ochrobactrum anthropi and Bacillus cereus, a commercial inoculum, consortia obtained from soil and groundwater contaminated with hydrocarbons and a consortium from an uncontaminated area. In the respirometric experiments it was evaluated the capability of the native microorganisms present in the soil from a petrol station to biodegrade the diesel oils. The redox indicator experiments showed that only the consortia, even that from an uncontaminated area, were able to biodegrade the weathered diesel. In 48 days, the removal of the total petroleum hydrocarbons (TPH) in the respirometric experiments was approximately 2.5 times greater when the commercial diesel oil was used. This difference was caused by the consumption of labile hydrocarbons, present in greater quantities in the commercial diesel oil, as demonstrated by gas chromatographic analyses. Thus, results indicate that biodegradability studies that do not consider the weathering effect of the pollutants may over estimate biodegradation rates and when the bioaugmentation is necessary, the best strategy would be that one based on injection of consortia, because even cultures with recognised capability of biodegrading hydrocarbons may fail when applied isolated. PMID:24031193

Assessing the environmental sustainability of ethanol from integrated biorefineries.

PubMed

Falano, Temitope; Jeswani, Harish K; Azapagic, Adisa

2014-06-01

This paper considers the life cycle environmental sustainability of ethanol produced in integrated biorefineries together with chemicals and energy. Four types of second-generation feedstocks are considered: wheat straw, forest residue, poplar, and miscanthus. Seven out of 11 environmental impacts from ethanol are negative, including greenhouse gas (GHG) emissions, when the system is credited for the co-products, indicating environmental savings. Ethanol from poplar is the best and straw the worst option for most impacts. Land use change from forest to miscanthus increases the GHG emissions several-fold. For poplar, the effect is opposite: converting grassland to forest reduces the emissions by three-fold. Compared to fossil and first-generation ethanol, ethanol from integrated biorefineries is more sustainable for most impacts, with the exception of wheat straw. Pure ethanol saves up to 87% of GHG emissions compared to petrol per MJ of fuel. However, for the current 5% ethanol-petrol blends, the savings are much smaller (<3%). Therefore, unless much higher blends become widespread, the contribution of ethanol from integrated biorefineries to the reduction of GHG emissions will be insignificant. Yet, higher ethanol blends would lead to an increase in some impacts, notably terrestrial and freshwater toxicity as well as eutrophication for some feedstocks. © 2014 The Authors. Biotechnology Journal published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Zr diffusion in titanite

NASA Astrophysics Data System (ADS)

Cherniak, D. J.

2006-11-01

Chemical diffusion of Zr under anhydrous, pO2-buffered conditions has been measured in natural titanite. The source of diffusant was either zircon powder or a ZrO2-Al2O3-titanite mixture. Experiments were run in sealed silica glass capsules with solid buffers (to buffer at NNO or QFM). Rutherford Backscattering Spectrometry (RBS) was used to measure diffusion profiles. The following Arrhenius parameters were obtained for Zr diffusion parallel to c over the temperature range 753-1,100°C under NNO-buffered conditions: D Zr = 5.33 × 10-7 exp(-325 ± 30 kJ mol-1/RT) m2 s-1 Diffusivities are similar for experiments buffered at QFM. These data suggest that titanite should be moderately retentive of Zr chemical signatures, with diffusivities slower than those for O and Pb in titanite, but faster than those for Sr and the REE. When applied in evaluation of the relative robustness of the recently developed Zr-in-titanite geothermometer (Hayden and Watson, Abstract, 16th V.M. Goldschmidt Conference 2006), these findings suggest that Zr concentrations in titanite will be less likely to be affected by later thermal disturbance than the geothermometer based on Zr concentrations in rutile (Zack et al. in Contrib Mineral Petrol 148:471-488, 2004; Watson et al. in Contrib Mineral. Petrol, 2006), but much less resistant to diffusional alteration subsequent to crystallization than the Ti-in-Zircon geothermometer (Watson and Harrison in Science 308:841-844, 2005).

Particle and carbon dioxide emissions from passenger vehicles operating on unleaded petrol and LPG fuel.

PubMed

Ristovski, Z D; Jayaratne, E R; Morawska, L; Ayoko, G A; Lim, M

2005-06-01

A comprehensive study of the particle and carbon dioxide emissions from a fleet of six dedicated liquefied petroleum gas (LPG) powered and five unleaded petrol (ULP) powered new Ford Falcon Forte passenger vehicles was carried out on a chassis dynamometer at four different vehicle speeds--0 (idle), 40, 60, 80 and 100 km h(-1). Emission factors and their relative values between the two fuel types together with a statistical significance for any difference were estimated for each parameter. In general, LPG was found to be a 'cleaner' fuel, although in most cases, the differences were not statistically significant owing to the large variations between emissions from different vehicles. The particle number emission factors ranged from 10(11) to 10(13) km(-1) and was over 70% less with LPG compared to ULP. Corresponding differences in particle mass emission factor between the two fuels were small and ranged from the order of 10 microg km(-1) at 40 to about 1000 microg km(-1) at 100 km h(-1). The count median particle diameter (CMD) ranged from 20 to 35 nm and was larger with LPG than with ULP in all modes except the idle mode. Carbon dioxide emission factors ranged from about 300 to 400 g km(-1) at 40 km h(-1), falling with increasing speed to about 200 g km(-1) at 100 km h(-1). At all speeds, the values were 10% to 18% greater with ULP than with LPG.

Challenging times ahead.

PubMed

While, Alison

2008-07-01

The global economic challenges will not only affect the banks but also healthcare staff and their patients. Indeed, no-one will be unaffected. At this moment community nurses are not being properly reimbursed for the cost of using their cars to deliver care in the home as the price of petrol rises ever higher and older people are counting the cost of ever rising energy and food costs. Additionally there will be less extra money available to fund public services as the government attempts to balance its expenditure against tax receipts without further increasing government debt.

Antibacterial and antifungal activities of Euroschinus papuanus.

PubMed

Khan, M R; Omoloso, A D; Kihara, M

2004-06-01

The crude methanolic extracts of the leaves, stem bark, stem heart wood, root bark and root heart wood of Euroschinus papuanus and the fractions obtained on partitioning with petrol, dichloromethane (D), ethyl acetate (E) and butanol (B), exhibited a broad spectrum antibacterial activity. Fractionation drastically enhanced the activity. Excellent activity was demonstrated by the E fractions of stem heart wood, D of root bark, and E of root heart wood. Antifungal activity was exhibited by the B fractions of leaves, stem heartwood and root bark. Copyright 2004 Elsevier B.V.

LNG projects make progress in Oman and Yemen

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1997-02-24

Two LNG projects in the Middle East, one in Oman and the other in Yemen, are due on stream at the turn of the century--each the largest single project ever put together in its country. Officials described their projects at a yearend 1996 conference in Paris by Institut Francais du Petrole and Petrostrategies. The Oman project develops gas reserves, does gas processing, and transports the gas 360 km to a liquefaction plant to be built on the coast. The Yemen project involves a liquefaction plant and an export terminal.

Mechanics

NASA Astrophysics Data System (ADS)

Maestro, P.; Gaffet, E.; Le Caër, G.; Mocellin, A.; Reynaud, E.; Rouxel, T.; Soulard, M.; Patarin, J.; Thilly, L.; Lecouturier, F.

Inorganic reinforcements are used in rubber, and in particular in tyre treads for light vehicles, in order to improve the compromise between three key features of tyres: road holding performance or road adherence, especially when the road is wet or snow-covered (road safety), roll resistance (petrol consumption), and resistance to wear (lifetime of the tyre). Over the last ten years, highly dispersible silicas (HDS) developed by Rhodia have been more and more widely used as a substitute for the traditionally used carbon black. The advantage with HDS materials is that they improve road holding and reduce roll resistance, while maintaining the same level of resistance to wear.

Wind turbines acoustic measurements

NASA Astrophysics Data System (ADS)

Trematerra, Amelia; Iannace, Gino

2017-07-01

The importance of wind turbines has increased over the last few years throughout the European Community. The European energy policy guidelines state that for the year 2020 20% of all energy must be produced by alternative energy sources. Wind turbines are an important type of energy production without petrol. A wind speed in a range from 2.5 m/s to 25.0 m/s is needed. One of the obstacles to the widespread diffusion of wind turbine is noise generation. This work presents some noise measurements of wind turbines in the South of Italy, and discusses the noise problems for the people living near wind farms.

Research on using Mineral Sorbents for A Sorption Process in the Environment Contaminated with Petroleum Substances

NASA Astrophysics Data System (ADS)

Pijarowski, Piotr Marek; Tic, Wilhelm Jan

2014-06-01

A research on diatomite sorbents was carried out to investigate their ability to remove hazardous substances from oil spillages. We used two types of sorbents available on the market with differences in material density and particles size of composition. As sorbents we used Ekoterm oil and unleaded petrol 95 coming from refinery PKN Orlen S.A. Two types of sorbents with similar chemical composition but different granulometric composition were used. They are marked as D1 and C1 samples. The fastest absorbent was C1, but D1 sample was the most absorptive.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chan, G.Y.; Chui, V.W.; Wong, M.H.

Samples of roadside dust were collected from 30 sites in Hong Kong. The total concentrations of 10 metals in the samples were analyzed, and the correlation coefficients among the metal contents and the annual average daily traffic (AADT) in 1986 were determined. Pb was found to have a significant correlation (P less than 0.01) with AADT. No correlation was found between Al, Ba, Cd, Cr, Cu, Fe, Mn, Ni, and Zn with respect to AADT. A general decrease in the level of Pb in roadside dust in the past few years has been observed since the reduction in the levelmore » of lead in petrol.« less

Impact of excess NOx emissions from diesel cars on air quality, public health and eutrophication in Europe

NASA Astrophysics Data System (ADS)

Jonson, J. E.; Borken-Kleefeld, J.; Simpson, D.; Nyíri, A.; Posch, M.; Heyes, C.

2017-09-01

Diesel cars have been emitting four to seven times more NOx in on-road driving than in type approval tests. These ‘excess emissions’ are a consequence of deliberate design of the vehicle’s after-treatment system, as investigations during the ‘Dieselgate’ scandal have revealed. Here we calculate health and environmental impacts of these excess NOx emissions in all European countries for the year 2013. We use national emissions reported officially under the UNECE Convention for Long-range Transport of Atmospheric Pollutants and employ the EMEP MSC-W Chemistry Transport Model and the GAINS Integrated Assessment Model to determine atmospheric concentrations and resulting impacts. We compare with impacts from hypothetical emissions where light duty diesel vehicles are assumed to emit only as much as their respective type approval limit value or as little as petrol cars of the same age. Excess NO2 concentrations can also have direct health impacts, but these overlap with the impacts from particulate matter (PM) and are not included here. We estimate that almost 10 000 premature deaths from PM2.5 and ozone in the adult population (age >30 years) can be attributed to the NOx emissions from diesel cars and light commercial vehicles in EU28 plus Norway and Switzerland in 2013. About 50% of these could have been avoided if diesel limits had been achieved also in on-road driving; and had diesel cars emitted as little NOx as petrol cars, 80% of these premature deaths could have been avoided. Ecosystem eutrophication impacts (critical load exceedances) from the same diesel vehicles would also have been reduced at similar rates as for the health effects.

Associations of short-term exposure to traffic-related air pollution with cardiovascular and respiratory hospital admissions in London, UK.

PubMed

Samoli, Evangelia; Atkinson, Richard W; Analitis, Antonis; Fuller, Gary W; Green, David C; Mudway, Ian; Anderson, H Ross; Kelly, Frank J

2016-05-01

There is evidence of adverse associations between short-term exposure to traffic-related pollution and health, but little is known about the relative contribution of the various sources and particulate constituents. For each day for 2011-2012 in London, UK over 100 air pollutant metrics were assembled using monitors, modelling and chemical analyses. We selected a priori metrics indicative of traffic sources: general traffic, petrol exhaust, diesel exhaust and non-exhaust (mineral dust, brake and tyre wear). Using Poisson regression models, controlling for time-varying confounders, we derived effect estimates for cardiovascular and respiratory hospital admissions at prespecified lags and evaluated the sensitivity of estimates to multipollutant modelling and effect modification by season. For single day exposure, we found consistent associations between adult (15-64 years) cardiovascular and paediatric (0-14 years) respiratory admissions with elemental and black carbon (EC/BC), ranging from 0.56% to 1.65% increase per IQR change, and to a lesser degree with carbon monoxide (CO) and aluminium (Al). The average of past 7 days EC/BC exposure was associated with elderly (65+ years) cardiovascular admissions. Indicated associations were higher during the warm period of the year. Although effect estimates were sensitive to the adjustment for other pollutants they remained consistent in direction, indicating independence of associations from different sources, especially between diesel and petrol engines, as well as mineral dust. Our results suggest that exhaust related pollutants are associated with increased numbers of adult cardiovascular and paediatric respiratory hospitalisations. More extensive monitoring in urban centres is required to further elucidate the associations. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Associations of short-term exposure to traffic-related air pollution with cardiovascular and respiratory hospital admissions in London, UK

PubMed Central

Samoli, Evangelia; Atkinson, Richard W; Analitis, Antonis; Fuller, Gary W; Green, David C; Mudway, Ian; Anderson, H Ross; Kelly, Frank J

2016-01-01

Objectives There is evidence of adverse associations between short-term exposure to traffic-related pollution and health, but little is known about the relative contribution of the various sources and particulate constituents. Methods For each day for 2011–2012 in London, UK over 100 air pollutant metrics were assembled using monitors, modelling and chemical analyses. We selected a priori metrics indicative of traffic sources: general traffic, petrol exhaust, diesel exhaust and non-exhaust (mineral dust, brake and tyre wear). Using Poisson regression models, controlling for time-varying confounders, we derived effect estimates for cardiovascular and respiratory hospital admissions at prespecified lags and evaluated the sensitivity of estimates to multipollutant modelling and effect modification by season. Results For single day exposure, we found consistent associations between adult (15–64 years) cardiovascular and paediatric (0–14 years) respiratory admissions with elemental and black carbon (EC/BC), ranging from 0.56% to 1.65% increase per IQR change, and to a lesser degree with carbon monoxide (CO) and aluminium (Al). The average of past 7 days EC/BC exposure was associated with elderly (65+ years) cardiovascular admissions. Indicated associations were higher during the warm period of the year. Although effect estimates were sensitive to the adjustment for other pollutants they remained consistent in direction, indicating independence of associations from different sources, especially between diesel and petrol engines, as well as mineral dust. Conclusions Our results suggest that exhaust related pollutants are associated with increased numbers of adult cardiovascular and paediatric respiratory hospitalisations. More extensive monitoring in urban centres is required to further elucidate the associations. PMID:26884048

Isotopic identification of natural vs. anthropogenic lead sources in marine sediments from the inner Ría de Vigo (NW Spain).

PubMed

Álvarez-Iglesias, P; Rubio, B; Millos, J

2012-10-15

San Simón Bay, the inner part of the Ría de Vigo (NW Spain), an area previously identified as highly polluted by Pb, was selected for the application of Pb stable isotope ratios as a fingerprinting tool in subtidal and intertidal sediment cores. Lead isotopic ratios were determined by inductively coupled plasma mass spectrometry on extracts from bulk samples after total acid digestion. Depth-wise profiles of (206)Pb/(207)Pb, (206)Pb/(204)Pb, (207)Pb/(204)Pb, (208)Pb/(204)Pb and (208)Pb/(207)Pb ratios showed, in general, an upward decrease for both intertidal and subtidal sediments as a consequence of the anthropogenic activities over the last century, or centuries. Waste channel samples from a nearby ceramic factory showed characteristic Pb stable isotope ratios different from those typical of coal and petrol. Natural isotope ratios from non-polluted samples were established for the study area, differentiating sediments from granitic or schist-gneiss sources. A binary mixing model employed on the polluted samples allowed estimating the anthropogenic inputs to the bay. These inputs represented between 25 and 98% of Pb inputs in intertidal samples, and 9-84% in subtidal samples, their contributions varying with time. Anthropogenic sources were apportioned according to a three-source model. Coal combustion-related emissions were the main anthropogenic source Pb to the bay (60-70%) before the establishment of the ceramic factory in the area (in the 1970s) which has since constituted the main source (95-100%), followed by petrol-related emissions. The Pb inputs history for the intertidal area was determined for the 20th century, and, for the subtidal area, the 19th and 20th centuries. Copyright © 2012 Elsevier B.V. All rights reserved.

Polycyclic aromatic hydrocarbons over a tropical urban and a high altitude Himalayan Station in India: Temporal variation and source apportionment

NASA Astrophysics Data System (ADS)

Ray, Debajyoti; Chatterjee, Abhijit; Majumdar, Dipanjali; Ghosh, Sanjay K.; Raha, Sibaji

2017-11-01

The temporal variations and major sources of polycyclic aromatic hydrocarbons (PAH) intrinsic to PM10 were investigated over a tropical urban atmosphere on the Indo-Gangetic Plain (IGP) and for the first time over a high altitude urban atmosphere at eastern Himalaya in India. Samples were collected over Kolkata, a megacity and Darjeeling, a high altitude (2200 m asl) hill station in eastern India during the dry season (October 2015-May 2016). Fourteen PAHs were detected and quantified over Kolkata and Darjeeling during three consecutive seasons, viz., post-monsoon, winter and pre-monsoon. The total-PAHs concentrations were in the order of winter (78.08-146.71 ngm- 3) > post-monsoon (83.42-113.52 ngm- 3) > pre-monsoon (37.65-109.27 ngm- 3) at Kolkata, whereas post-monsoon (22.72-36.60 ngm- 3) > winter (8.52-28.43 ngm- 3) > pre-monsoon (5.45-13.34 ngm- 3) at Darjeeling. The observed seasonality of PAHs at Kolkata vis-a-vis Darjeeling has been explored in the light of anthropogenic activities, boundary layer dynamics and meteorological parameters such as temperature, relative humidity, wind speed and solar radiation. Negative correlation was observed between total-PAHs and temperature, wind speed and solar radiation over Kolkata and Darjeeling. The positive matrix factorization (PMF) model calculations suggested that coal (26%), petrol (24%) and diesel (17%) combustion, commercial and household kitchens (18%) and municipal solid waste incineration (15%) are the possible contributors to the PM10 associated PAHs over Kolkata whereas diesel (37%), commercial and household kitchens (23%), coal (21%) and petrol (20%) are the possible PM10 associated PAH sources over Darjeeling.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Onyari, J.M.; Wandiga, S.O.; Njenga, G.K.

The advent of modern industrialization and, in particular, the motor vehicle has witnessed dramatic increases in lead usage both as a component of lead-acid storage battery and from 1923 as organic lead alkyl anti-knock additive in petroleum. Several workers have established a correlation between increasing lead concentration in roadside soils and vehicular traffic density. Although researchers studied the heavy metal content in Lake Victoria sediments, no urban roadside soils were investigated. Since lead is used as a petrol additive in Kenya, it is necessary to document the extent and magnitude of lead contamination of roadside soils in inland and coastalmore » urban environments and evaluate its environmental implications.« less

Two-stroke engine diagnostics and design

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1992-01-01

This paper focuses on research and development efforts on two-stroke cycle engines for automotive applications. Partial contents include: Velocity Field Characteristics in Motored Two-Stroke Ported Engines; Flow Vector Measurements at the Scavenging Ports in a Fired Two-Stroke Engine; A Study on Exhaust Dynamic Effect of Two-Stroke Motorcycle Petrol Engine; Characterization of Ignition and Parametric Study of a Two-Stroke-Cycle Direct-Injected Gasoline Engine; LDV Measurements of Intake Port Flow in a Two-Stroke Engine with and without Combustion; Appraisal of Regenerative Blowers for Scavenging of Small 2T S.I. Powerplants; and Development Experience of a Poppet-Valved Two-Stroke Flagship Engine.

Assessing air quality in Aksaray with time series analysis

NASA Astrophysics Data System (ADS)

Kadilar, Gamze Özel; Kadilar, Cem

2017-04-01

Sulphur dioxide (SO2) is a major air pollutant caused by the dominant usage of diesel, petrol and fuels by vehicles and industries. One of the most air-polluted city in Turkey is Aksaray. Hence, in this study, the level of SO2 is analyzed in Aksaray based on the database monitored at air quality monitoring station of Turkey. Seasonal Autoregressive Integrated Moving Average (SARIMA) approach is used to forecast the level of SO2 air quality parameter. The results indicate that the seasonal ARIMA model provides reliable and satisfactory predictions for the air quality parameters and expected to be an alternative tool for practical assessment and justification.

Electron beam welding passes initial test

DOE Office of Scientific and Technical Information (OSTI.GOV)

de Sirvy, B.

1979-11-01

Once the new electron-beam welding process is coupled with vertical or J-curve pipelaying techniques, Total-Compagnie Francaise des Petroles (Gestion and Recherches) will be able to offer a system capable of laying up to 36-in. pipe in deep water (1000-9900 ft) at a pace competitive with the best performance of a shallow-water barge: 8200 ft in 24 hr. Electron-beam welding provides the fast, single-station joining needed to make J-curve laying economical. Tests recently demonstrated that this welding technique can join 1.25-in.-wall, 24-in. pipe in less than 3 min; conventional processes require 1-1 1/2 hr.

Effects of fO2, fH2O and aoxide on formation and density of extended planar defects in olivine

NASA Astrophysics Data System (ADS)

Burgess, K.; Cooper, R. F.

2011-12-01

Melt inclusions are used in geochemistry to inform our understanding of many physiochemical processes taking place in the mantle, such as melting, melt-rock interactions and magma mixing. Fundamental to this interpretation of melt inclusions is the assumption that they act as closed systems, i.e., they are chemically isolated after trapping and preserve primitive magma compositions. However, recent work indicates that volatiles (e.g., H and F) can be rapidly reset [Portnyagin et al., 2008], and the diffusion mechanisms and rates in tracer diffusion experiments, specifically of REEs, are a matter of some debate [Spandler and O'Neill, 2010; Cherniak, 2010]. The compendium of observations and experiments suggests a role of planar extended defects in effecting and affecting diffusion kinetics in olivine. Planar extended defects are the exothermic condensation of charged point defects into two-dimensional structures, their third dimension insufficient (i.e., sub-unit cell) to describe them as a unique phase. These planar defects, in a manner similar to mechanisms of "pipe" diffusion along dislocations and of grain boundary diffusion, can lead to measured diffusivities far greater than the lattice diffusivity, and their overall effect on flux is proportional to their spatial density [cf. Hart, 1957]. High-resolution TEM and AEM investigation of experimental olivine-basalt samples show the presence of planar defects near the olivine-melt interface, with the area fraction of the high-contrast defects in the images being greatest at high fO2 and/or fH2O while temperature has an effect on the defect dimensions but not total areal density. EDS analysis of the interface regions indicate high Ti/Ca and Ti/Al ratios compared to the glass; the stability of intercalated humite-type defects in olivine, a planar defect type found in some natural olivines [e.g., Risold et al., 2001; Hermann et al., 2007], is increased to higher temperature by the incorporation of Ti. Activities of oxides clearly affect the presence and density of the defects. Olivine-ilmenite experiments were also carried out in varying fO2 and fH2O conditions. Thermodynamic calculations for concentrations of point defects, defect association(s) and defect condensation in olivine can relate experimental data for measured diffusivities to discerning natural conditions where condensed-defect, fast-path diffusion in olivine could be significant. Planar extended defects can potentially play a role in the kinetics of deformation of olivine in the mantle, particularly as the condensation reaction lowers the activity of mobile point defects. Cherniak, Am. Mineral. 95 (2010) 362-368. Hart, Acta Met. 5 (1957) 597. Hermann et al., Contrib. Mineral. Petrol. 153 (2007) 417-428. Portnyagin et al., Earth Planet. Sci.Lett. 272 (2008) 541-552. Risold et al., Contrib. Mineral. Petrol. 142 (2001) 619-628. Spandler and O'Neill, Contrib. Mineral. Petrol. 159 (2010) 791-818.

Tracing fetal and childhood exposure to lead using isotope analysis of deciduous teeth

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shepherd, Thomas J.; British Geological Survey, Keyworth, Nottingham; Dirks, Wendy

We report progress in using the isotopic composition and concentration of Pb in the dentine and enamel of deciduous teeth to provide a high resolution time frame of exposure to Pb during fetal development and early childhood. Isotope measurements (total Pb and {sup 208}Pb/{sup 206}Pb, {sup 207}Pb/{sup 206}Pb ratios) were acquired by laser ablation inductively coupled mass spectrometry at contiguous 100 micron intervals across thin sections of the teeth; from the outer enamel surface to the pulp cavity. Teeth samples (n=10) were selected from two cohorts of children, aged 5–8 years, living in NE England. By integrating the isotope datamore » with histological analysis of the teeth, using the daily incremental lines in dentine, we were able to assign true estimated ages to each ablation point (first 2–3 years for molars, first 1–2 years for incisors+pre-natal growth). Significant differences were observed in the isotope composition and concentration of Pb between children, reflecting differences in the timing and sources of exposure during early childhood. Those born in 2000, after the withdrawal of leaded petrol in 1999, have the lowest dentine Pb levels (<0.2 µg Pb/g) with {sup 208}Pb/{sup 206}Pb (mean ±2σ: 2.126–2.079) {sup 208}Pb/{sup 206}Pb (mean ±2σ: 0.879–0.856) ratios that correlate very closely with modern day Western European industrial aerosols (PM{sub 10}, PM{sub 2.5}) suggesting that diffuse airborne pollution was probably the primary source and exposure pathway. Legacy lead, if present, is insignificant. For those born in 1997, dentine lead levels are typically higher (>0.4 µgPb/g) with {sup 208}Pb/{sup 206}Pb (mean ±2σ: 2.145–2.117) {sup 208}Pb/{sup 206}Pb (mean ±2σ: 0.898–0.882) ratios that can be modelled as a binary mix between industrial aerosols and leaded petrol emissions. Short duration, high intensity exposure events (1–2 months) were readily identified, together with evidence that dentine provides a good proxy for childhood changes in the isotope composition of blood Pb. Our pilot study confirms that laser ablation Pb isotope analysis of deciduous teeth, when carried out in conjunction with histological analysis, permits a reconstruction of the timing, duration and source of exposure to Pb during early childhood. With further development, this approach has the potential to study larger cohorts and appraise environments where the levels of exposure to Pb are much higher. - Highlights: • Reconstructing a high resolution chronology of early childhood exposure to lead. • Combined laser ablation lead isotope – histological analysis of children's teeth. • Using dentine to recover information on the intensity, duration and source of lead. • Importance of industrial airborne lead pollution in a post-leaded petrol era.« less

Ancient Pb and Ti mobilization revealed by Scanning Ion Imaging

NASA Astrophysics Data System (ADS)

Kusiak, Monika A.; Whitehouse, Martin J.; Wilde, Simon A.

2014-05-01

Zircons from strongly layered early Archean ortho- and paragneisses in ultra-high temperature (UHT) metamorphic rocks of the Napier Complex, Enderby Land, East Antarctica are characterized by complex U-Th-Pb systematics [1,2,3]. A large number of zircons from three samples, Gage Ridge, Mount Sones and Dallwitz Nunatak, are reversely discordant (U/Pb ages older than 207Pb/206Pb ages) with the oldest date of 3.9 Ga [4] (for the grain from Gage Ridge orthogneiss). To further investigate this process, we utilized a novel high spatial resolution Scanning Ion Imaging technique on the CAMECA IMS 1280 at the Natural History Museum in Stockholm. Areas of 70 μm x 70 μm were selected for imaging in mono- and multicollection modes using a ~2 μm rastered primary beam to map out the distribution of 48Ti, 89Y, 180Hf, 232Th, 238U, 204Pb, 206Pb and 207Pb. The ion maps reveal variable distribution of certain elements within analysed grains that can be compared to their CL response. Yttrium, together with U and Th, exhibits zonation visible on the CL images, Hf shows expected minimal variation. Unusual patchiness is visible in the map for Ti and Pb distribution. The bright patches with enhanced signal do not correspond to any zones or to crystal imperfections (e.g. cracks). The presence of patchy titanium is likely to affect Ti-in-zircon thermometry, and patchy Pb affecting 207Pb/206Pb ages, usually considered as more robust for Archean zircons. Using the WinImage program, we produced 207Pb/206Pb ratio maps that allow calculation of 207Pb/206Pb ages for spots of any size within the frame of the picture and at any time after data collection. This provides a new and unique method for obtaining age information from zircon. These maps show areas of enhanced brightness where the 207Pb/206Pb ratio is higher and demonstrate that within these small areas (μm scale) the apparent 207Pb/206Pb age is older, in some of these patches even > 4 Ga. These data are a result of ancient Pb mobilization, which is independent of the degree of metamictisation, oxygen isotope and REE content of the zircons [5]. The Antarctic zircons experienced ancient Ti and Pb mobilization and redistribution, most likely caused by polyphase metamorphism at ~2.8 Ga and ~2.5 Ga, the latter documented as reaching temperatures of >1100ºC [5]. References: [1] Williams et al., 1984, Contr. Min. Petrol. 88, 322-327. [2] Black et al., (1986), Contr. Min. Petrol. 94, 427-437. [3] Harley & Kelly, 2007, Earth's Oldest Rocks: Developments in Precambrian Geology 15, 149-186. [4] Kusiak et al., 2013, Geology 41, 291-294. [5] Kusiak et al., 2013, American J. of Sci. 313, 933-967. [5] Hokada et al., 2004, Contr. Min. Petrol. 147, 1-20.

An unusual cause of cold injury: liquified petroleum gas leakage.

PubMed

Seyhan, Nevra; Jasharllari, Lorenc; Kayapınar, Muhammed; Savacı, Nedim

2011-11-01

Liquefied petroleum gas (LPG) is an odorless and colorless gas that is a mixture of hydrocarbons (propane and butane). It is now more commonly preferred among drivers as an auto-gas throughout the world because it is cheaper than petrol or diesel and produces the same amount of energy. Because of its rapid vaporization and consequent lowering of temperature, it may cause severe cold injuries. A 33-year-old male who suffered from hand burn due to LPG is presented in this article. In LPG-converted cars, if the conversion has not been done properly, LPG may leak. Thus, the public must be informed of this potential danger while undertaking repairs of their vehicles.

The experimental investigation of the ignition petrol mechanism at high temperature metal single particles

NASA Astrophysics Data System (ADS)

Zakharevich, Arkadiy V.; Osotova, Diana S.

2015-01-01

The flammable substance by single "hot" metallic particle ignition mechanism are experimentally investigated. On the basis experimental data it is established that the gasoline ignition occurs only with interaction of the mixture of its vapors with air and "hot" particle with the vapors concentrations, which correspond to the evaporating the gasoline conditions at room temperatures. The probability of gasoline vapors mixture with air igniting rapidly is reduced in proportion to their withdrawal from the evaporation surface. Ignition occurs neither in the vapor phase nor on the gasoline surface, even if particle is immersed in it in full or in partly, if the particle temperature is lower than the critical.

Neodymium Isotope Variability at the Grain Scale in the Sub-Continental Lithospheric Mantle: NdO+ Analyses of Individual Clinopyroxene Grains (<5 ng Nd aliquots) from a Kilbourne Hole Harzburgitic Xenolith.

NASA Astrophysics Data System (ADS)

Harvey, J.; Honn, D.; Baxter, E. F.; Warren, J. M.; Hammond, S.; Walshaw, R.

2014-12-01

It is evident that at scales of 102 to 10-2 m there is significant isotopic heterogeneity in the mantle that is not always reflected in primitive melts. The "Os isotopic gap"[1] is one such manifestation of this phenomenon but a similar offset exists between the Nd isotope composition of abyssal peridotites and the mid-ocean ridge basalts that they are inferred to have produced[2]. This study takes advantage of recent advances in the analysis of Nd isotopes as NdO+[3,4] which permit the precise analysis of single clinopyroxene grains (<1 mg mass; <5 ng Nd) from a continental harzburgitic xenolith from Kilbourne Hole, NM. Analyses of aggregates of clinopyroxenes from 5 Kilbourne Hole xenoliths reveal a wide range of 143Nd/144Nd (0.513011 ± 28 to 0.513615 ±19)[5]. This study demonstrates significant grain-to-grain isotopic heterogeneity at a scale of 10-2 m (143Nd/144Nd = 0.513089 ± 78 to 0.513364 ± 74) which (i) is equivalent to the range of values for Pacific MORB[6] and (ii) is more primitive than local basalts with an asthenospheric signature[7]. This suggests that small-scale refractory domains exist within the mantle which are either not sampled during partial melting or whose presence is obscured by the melting of higher volumes of more fusible material. Ref:[1]Alard et al. (2005) Nature 436, 1005-1008 [2]Warren et al. (2009) JGR 114, B12203, doi:10.1029/2008JB006186 [3]Harvey and Baxter (2009) Chem. Geol. 258, 251-257 [4]Honn et al. (2013) AGU Fall abstr. V33-2722 [5]Harvey et al. (2012) J. Petrol. 53, 1709-1742 [6]Hofmann (1997) Nature 385, 219-229 [7]Thompson et al. (2005) J. Petrol. 46, 1603-1643

Non-seatbelt use and associated factors among Thai drivers during Songkran festival.

PubMed

Siviroj, Penprapa; Peltzer, Karl; Pengpid, Supa; Morarit, Sompong

2012-08-04

Road traffic accidents are the second largest cause of burden of disease in Thailand, largely attributable to behavioural risk factors including drinking and driving, speeding, substance abuse and failure to use seatbelts. The aim of this study was to assess the prevalence and associated factors of non-seatbelt use among drivers during Songkran festival in Thailand. A cross-sectional survey has been performed to determine the prevalence of seatbelt use among Thai drivers (N=13722) during four days of the Songkran festival. For this sample the population of drivers was consecutively selected from 12 petrol stations in four provinces from each of the four main geographical regions of Thailand. The study was conducted at petrol stations at roads in town, outside town and highway at different time intervals when trained field staff administered a structured questionnaire and performed an observation checklist on seat belt use. An overall prevalence of 28.4% of non-seatbelt use among drivers was found. In multivariable analysis demographics (being male, younger age, coming from the Northern or Southern region in Thailand), environmental factors (earlier during the Songkran festival, in the morning and late evening and on main roads in town), seatbelt use experiences and attitudes (having been in an accident before, never having used a seatbelt, no intention to use a seatbelt, lack of awareness of danger of non-seatbelt use and lower perceived risk of being caught with non-seatbelt use) and lower exposure to road safety awareness (RSA) campaign (less frequent exposure to RSA campaign, less frequent following of RTI statistics and not talking with others about the RSA campaign) were associated with non-seatbelt use. Rates of non-seatbelt use by Thai drivers during Songkran festival was 28.4%. Lower exposure to the RSA campaign was found to be associated with non-seatbelt use among drivers during the Songkran festival.

Non-seatbelt use and associated factors among Thai drivers during Songkran festival

PubMed Central

2012-01-01

Background Road traffic accidents are the second largest cause of burden of disease in Thailand, largely attributable to behavioural risk factors including drinking and driving, speeding, substance abuse and failure to use seatbelts. The aim of this study was to assess the prevalence and associated factors of non-seatbelt use among drivers during Songkran festival in Thailand. Methods A cross-sectional survey has been performed to determine the prevalence of seatbelt use among Thai drivers (N=13722) during four days of the Songkran festival. For this sample the population of drivers was consecutively selected from 12 petrol stations in four provinces from each of the four main geographical regions of Thailand. The study was conducted at petrol stations at roads in town, outside town and highway at different time intervals when trained field staff administered a structured questionnaire and performed an observation checklist on seat belt use. Results An overall prevalence of 28.4% of non-seatbelt use among drivers was found. In multivariable analysis demographics (being male, younger age, coming from the Northern or Southern region in Thailand), environmental factors (earlier during the Songkran festival, in the morning and late evening and on main roads in town), seatbelt use experiences and attitudes (having been in an accident before, never having used a seatbelt, no intention to use a seatbelt, lack of awareness of danger of non-seatbelt use and lower perceived risk of being caught with non-seatbelt use) and lower exposure to road safety awareness (RSA) campaign (less frequent exposure to RSA campaign, less frequent following of RTI statistics and not talking with others about the RSA campaign) were associated with non-seatbelt use. Conclusion Rates of non-seatbelt use by Thai drivers during Songkran festival was 28.4%. Lower exposure to the RSA campaign was found to be associated with non-seatbelt use among drivers during the Songkran festival. PMID:22863275

Quantification of the efficiency of treatment of Anopheles gambiae breeding sites with petroleum products by local communities in areas of insecticide resistance in the Republic of Benin

PubMed Central

Djouaka, Rousseau F; Bakare, Adekunle A; Bankole, Honore S; Doannio, Julien MC MC; Kossou, Hortense; Akogbeto, Martin C

2007-01-01

Background The emergence of Anopheles populations capable of withstanding lethal doses of insecticides has weakened the efficacy of most insecticide based strategies of vector control and, has highlighted the need for developing new insecticidal molecules or, improving the efficacy of existing insecticides or abandoning those to which resistance has emerged. The use of petroleum products (PP) against mosquito larvae had an immense success during early programmes of malaria control, but these compounds were abandoned and replaced in the 1950s by synthetic insecticides probably because of the high performances given by these new products. In the current context of vector resistance, it is important to elucidate the empirical use of PP by quantifying their efficiencies on resistant strains of Anopheles. Methods Larvae of Anopheles Ladji a local resistant strain were exposed to increasing concentrations of various PP (kerosene, petrol and engine oils) for 24 hours and the lethal activities recorded. The highest concentration (HiC) having no lethal activity (also referred as the NOEL or no effect level) and the lowest concentration (LoC100) yielding 100% mortality were rated for each PP on the Ladji strain. Prior to laboratory analysis, KAP studies were conducted in three traditional communities were insecticide resistance is clearly established to confirm the use of PP against mosquitoes. Results Laboratory analysis of petrol, kerosene and engine oils, clearly established their lethal activities on resistant strains of Anopheles larvae. Contrary to existing references, this research revealed that exposed larvae of Anopheles were mostly killed by direct contact toxicity and not by suffocation as indicated in some earlier reports. Conclusion This research could serve as scientific basis to backup the empirical utilisation of PP on mosquito larvae and to envisage possibilities of using PP in some traditional settings where Anopheles have developed resistance to currently used insecticides. PMID:17488523

The role of the metasomatized oceanic lithosphere on the composition of mid-ocean ridge basalts from the East Pacific Rise

NASA Astrophysics Data System (ADS)

Shimizu, K.; Saal, A. E.

2016-12-01

In the present study, we evaluate the effect of melting of a metasomatized oceanic lithosphere on the chemical composition of MORB using the East Pacific Rise (EPR) mid-ocean ridge basalts (MORB) from the Quebrada-Discovery-GoFar (QDG) transform fault system, Northern EPR seamounts, and Macquarie Island [1-3]. EMORB from the QDG have trace element and volatile-refractory element ratios different from those measured in NEPR seamounts and Macquarie EMORB. The unique chemical composition of the QDG EMORB might indicate contribution from the oceanic lithosphere during the formation of intra-transform spreading centers due to clockwise rotation in Pacific-Nazca plate relative motion. In addition, the compositions of some of the Petit-spot lavas recently erupted along lithospheric fractures in the Pacific Plate in response to its flexure near the Japan Trench [4] have geochemical signatures that might suggest melts derived from a metasomatized oceanic mantle lithosphere. We evaluate this hypothesis using a geochemical model assuming a two-component asthenospheric mantle (DDMM and EDMM) and formation of hydrous cumulates in the oceanic mantle lithosphere by crystallization of low degree melts of the EDMM [3, 5]. The model suggests that melting of the hydrous cumulates can reproduce the composition of EMORB from QDG transform fault and some of the Petit-spot lavas. The process of melting the metasomatized oceanic lithosphere may significantly affect the chemical composition of MORB, and the common assumption for the purely asthenosphere origin of MORB could lead to inaccurate estimates of the Earth's upper mantle composition. We also show that similar process might affect not only oceanic, but also off-craton sub continental mantle lithosphere. References: [1] Niu et al., 2002 EPSL 199. [2] Kamenetsky et al., 2002 J Petrol 43. [3] Shimizu et al., 2016 GCA 176. [4] Hirano et al., 2006 Science 313. [5] Pilet et al., 2011 J Petrol 52.

Using mobile distributed pyrolysis facilities to deliver a forest residue resource for bio-fuel production

NASA Astrophysics Data System (ADS)

Brown, Duncan

Distributed mobile conversion facilities using either fast pyrolysis or torrefaction processes can be used to convert forest residues to more energy dense substances (bio-oil, bio-slurry or torrefied wood) that can be transported as feedstock for bio-fuel facilities. All feedstock are suited for gasification, which produces syngas that can be used to synthesise petrol or diesel via Fischer-Tropsch reactions, or produce hydrogen via water gas shift reactions. Alternatively, the bio-oil product of fast pyrolysis may be upgraded to produce petrol and diesel, or can undergo steam reformation to produce hydrogen. Implementing a network of mobile facilities reduces the energy content of forest residues delivered to a bio-fuel facility as mobile facilities use a fraction of the biomass energy content to meet thermal or electrical demands. The total energy delivered by bio-oil, bio-slurry and torrefied wood is 45%, 65% and 87% of the initial forest residue energy content, respectively. However, implementing mobile facilities is economically feasible when large transport distances are required. For an annual harvest of 1.717 million m3 (equivalent to 2000 ODTPD), transport costs are reduced to less than 40% of the total levelised delivered feedstock cost when mobile facilities are implemented; transport costs account for up to 80% of feedstock costs for conventional woodchip delivery. Torrefaction provides the lowest cost pathway of delivering a forest residue resource when using mobile facilities. Cost savings occur against woodchip delivery for annual forest residue harvests above 2.25 million m3 or when transport distances greater than 250 km are required. Important parameters that influence levelised delivered costs of feedstock are transport distances (forest residue spatial density), haul cost factors, thermal and electrical demands of mobile facilities, and initial moisture content of forest residues. Relocating mobile facilities can be optimised for lowest cost delivery as transport distances of raw biomass are reduced. The overall cost of bio-fuel production is determined by the feedstock delivery pathway and also the bio-fuel production process employed. Results show that the minimum cost of petrol and diesel production is 0.86 litre -1 when a bio-oil feedstock is upgraded. This corresponds to a 2750 TPD upgrading facility requiring an annual harvest of 4.30 million m3. The miniμm cost of hydrogen production is 2.92 kg -1, via the gasification of a woodchip feedstock and subsequent water gas shift reactions. This corresponds to a 1100 ODTPD facility and requires an annual harvest of 947,000 m3. The levelised cost of bio-fuel strongly depends on the size of annual harvest required for bio-fuel facilities. There are optimal harvest volumes (bio-fuel facility sizes) for each bio-fuel production route, which yield minimum bio-fuel production costs. These occur as the benefits of economies of scale for larger bio-fuel facilities compete against increasing transport costs for larger harvests. Optimal harvest volumes are larger for bio-fuel production routes that use feedstock sourced from mobile facilities, as mobile facilities reduce total transport requirements.

Feasibility Studies for a Mediterranean Neutrino Observatory - The NEMO.RD Project

NASA Astrophysics Data System (ADS)

de Marzo, C.; Ambriola, M.; Bellotti, R.; Cafagna, F.; Calicchio, M.; Ciacio, F.; Circella, M.; de Marzo, C.; Montaruli, T.; Falchieri, D.; Gabrielli, A.; Gandolfi, E.; Masetti, M.; Vitullo, C.; Zanarini, G.; Habel, R.; Usai, I.; Aiello, S.; Burrafato, G.; Caponetto, L.; Costanzo, E.; Lopresti, D.; Pappalardo, L.; Petta, C.; Randazzo, N.; Russo, G. V.; Troia, O.; Barnà, R.; D'Amico, V.; de Domenico, E.; de Pasquale, D.; Giacobbe, S.; Italiano, A.; Migliardo, F.; Salvato, G.; Trafirò, A.; Trimarchi, M.; Ameli, F.; Bonori, M.; Bottai, S.; Capone, A.; Desiati, P.; Massa, F.; Masullo, R.; Salusti, E.; Vicini, M.; Coniglione, R.; Migneco, E.; Piattelli, P.; Riccobene, R.; Sapienza, P.; Cordelli, M.; Trasatti, L.; Valente, V.; de Marchis, G.; Piccari, L.; Accerboni, E.; Mosetti, R.; Astraldi, M.; Gasparini, G. P.; Ulzega, A.; Orrù, P.

2000-06-01

The NEMO.RD Project is a feasibility study of a km3 underwater telescope for high energy astrophysical neutrinos to be located in the Mediterranea Sea. At present this study concerns: i) Monte Carlo simulation study of the capabilities of various arrays of phototubes in order to determine the detector geometry that can optimize performance and cost; ii) design of low power consumption electronic cards for data acquisition and transmission to shore; iii) feasibility study of mechanics, deployment, connection and maintenance of such a detector in collaboration with petrol industries having experience of undersea operations; iv) oceanographic exploration of various sites in search for the optimal one. A brief report on the status of points i) and iv) is presented here

Sound vibration signal processing for detection and identification detonation (knock) to optimize performance Otto engine

NASA Astrophysics Data System (ADS)

Sujono, A.; Santoso, B.; Juwana, W. E.

2016-03-01

Problems of detonation (knock) on Otto engine (petrol engine) is completely unresolved problem until now, especially if want to improve the performance. This research did sound vibration signal processing engine with a microphone sensor, for the detection and identification of detonation. A microphone that can be mounted is not attached to the cylinder block, that's high temperature, so that its performance will be more stable, durable and inexpensive. However, the method of analysis is not very easy, because a lot of noise (interference). Therefore the use of new methods of pattern recognition, through filtration, and the regression function normalized envelope. The result is quite good, can achieve a success rate of about 95%.

A High Fuel Consumption Efficiency Management Scheme for PHEVs Using an Adaptive Genetic Algorithm

PubMed Central

Lee, Wah Ching; Tsang, Kim Fung; Chi, Hao Ran; Hung, Faan Hei; Wu, Chung Kit; Chui, Kwok Tai; Lau, Wing Hong; Leung, Yat Wah

2015-01-01

A high fuel efficiency management scheme for plug-in hybrid electric vehicles (PHEVs) has been developed. In order to achieve fuel consumption reduction, an adaptive genetic algorithm scheme has been designed to adaptively manage the energy resource usage. The objective function of the genetic algorithm is implemented by designing a fuzzy logic controller which closely monitors and resembles the driving conditions and environment of PHEVs, thus trading off between petrol versus electricity for optimal driving efficiency. Comparison between calculated results and publicized data shows that the achieved efficiency of the fuzzified genetic algorithm is better by 10% than existing schemes. The developed scheme, if fully adopted, would help reduce over 600 tons of CO2 emissions worldwide every day. PMID:25587974

Performance Test on Compression Ignition Engine by Blending Ethanol and Waste Plastic Pyrolysis Oil with Cetane Additive

NASA Astrophysics Data System (ADS)

Padmanabhan, S.; Ganesan, S.; Jeswin Arputhabalan, J.; Chithrala, Varun; Ganesh Bairavan, P.

2017-05-01

The demand for diesel fuel is higher than that of petrol throughout the world hence seeking alternative to mineral diesel is a natural choice. Alternative fuels should be easily available at lower cost, environment friendly and fulfill energy needs without modifying engine’s operational parameters. Waste to energy is the trend in the selection of alternate fuels. In this work, Waste Plastic Pyrolysis oil (WPPO), Ethanol, Diesel blend with Cetane additive has been attempted as an alternative fuel. A Twin cylinder, Direct Injection engine was used to assess the engine performance and emission characteristics of waste plastic pyrolysis oil with cetane additive. Experimental results of blended plastic fuel and diesel fuel were compared.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Winterbone, D.E.; Richards, P.

A microprocessor controlled test bed was built for steady state mapping of petrol engines using a sweep mapping technique. The addition of an electric motor to the fast acting dynamometer allowed rapid load changes to be applied at nominally constant speed. This made it possible to consider the dynamic behaviour of the power generation sub-system of the engine. The engine was initially subjected to ramp changes of torque but these did not give consistent results. PRBS signals were then used for the same variable and a mathematical transfer function model developed for the engine power system. The engine was consideredmore » both as a continuous and sample data system. Results will be presented which show fuel management has an appreciable effect on the engine dynamic response.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joyce, R.J.; Natusch, D.F.S.; Richardson, D.W.

Blends of 15% methanol with petrol containing 1% isobutanol have been utilised by 45 vehicles operated for a period of two years. An additional 907 vehicles have been operated for approximately one year to obtain information about the distribution of M15 blends, about necessary co-solvent concentrations, and about general vehicle driveability. Initial studies have also been conducted using 15-20% emulsions of methanol with diesel in diesel-cycle engines. High methanol fuels ranging from M85 to M100 have been tested in six purpose-built vehicles and 45 retrofitted vehicles involving four different types of retrofit systems. In addition, high methanol fuels have alsomore » been tested in dieselcycle engines involving two different types of purpose-built engines, together with unmodified engines.« less

Experimental Study on the Plasma Purification for Diesel Engine Exhaust Gas

NASA Astrophysics Data System (ADS)

Chen, Jing; Zu, Kan; Wang, Mei

2018-02-01

It is known that the use of ternary catalysis is capable of significantly reducing the emission of pollutants from petrol vehicles. However, the disadvantages such as the temperature and other limitations make it unsuitable for diesel engines. The plasma-assisted catalyst technology has been applied in dealing with the diesel exhaust in the experiment in order to do further research on the effects of plasma in exhaust processing. The paper not only includes the experimental observation on the change of particle concentration after the operation of purification device, but also builds the kinetic model of chemical reactions to simulate the reactions of nitrogen oxides in plasma through using the software of Matlab, then compares the calculation results with experimental samples and finally gets some useful conclusions in practice.

Applications Of A Fibre Optic TV Holography System To The Study Of Large Automotive Structures.

NASA Astrophysics Data System (ADS)

Davies, Jeremy C.; Buckberry, Clive H.

1990-04-01

Mono-mode fibre optic components, including directional couplers and piezo-electric phase control elements, have been used to construct a TV holography system. The instrument has advantages of simplicity and ruggedness of construction and, with a 40m fibre optic link to a 600m argon ion laser, has proved to be an ideal tool for studying the structural behaviour of automotive assemblies. The TV holography system is described and two examples presented of its use: analysis of the deformation of a petrol engine cylinder bore due to head bolt forces, and the vibration study of a vehicle bodyshell subjected to wheel induced inputs. Limitations in the application of the technique are identified and future work to address these shortcomings outlined.

Sr-Nd-Pb isotope variability across and along the Ecuadorian volcanic arc

NASA Astrophysics Data System (ADS)

Ancellin, Marie-Anne; Samaniego, Pablo; Vlastélic, Ivan; Nauret, François; Gannoun, Mouhcine; Hidalgo, Silvana

2016-04-01

Determining the contribution of different potential sources in arc magma genesis is of paramount importance for discriminating the role of deep-seated processes at work in the slab and mantle wedge, as well as the process occurring during the magma ascent through the arc crust. The Ecuadorian volcanic arc (2°S - 1°N) results from the subduction of the oceanic Nazca plate below the continental south-American plate. This volcanic province, developed in front of the subducting Carnegie ridge, is characterized by at least 50-60 volcanic centres of Pleistocene-Holocene age, which are distributed along the Western and Eastern Cordilleras and in the back-arc region. Previous studies on this province focused on two main issues: (1) the role of the deep-seated process occurring at the level of the subducting slab and the mantle wedge ([1], [2]), and (2) the role of crustal process ([3]). In this work, we use existing and new (57 samples from 36 volcanoes of the whole Ecuadorian arc) major-trace element and Sr-Nd-Pb isotope data to resolve precisely magma compositional changes occurring across and along the volcanic arc and to precise the role of the heterogeneous crust underlying this arc segment. In the 207Pb/204Pb vs. 206Pb/204Pb diagram, most of Western Cordillera volcanic centres and Back arc volcanoes display a flat trend characterized by a large variation in 206Pb/204Pb (18.5 - 19.15), with little variation in 207Pb/204Pb (15.54-15.62). Along this trend, back arc volcanoes tend towards unradiogenic compositions with Reventador as end-member whereas western cordilleras volcanoes generally show more radiogenic compositions (Pilavo, Imbabura). In contrast, the Eastern cordillera volcanoes display more radiogenic 207Pb/204Pb (15.60 - 15.70) or 208Pb/204Pb (38.7 - 39) at a given 206Pb/204Pb compared to the Western cordillera with similar variation in 206Pb/204Pb (18.85 - 19.05). Extreme compositions are observed at Tungurahua and Antisana volcanoes. Several volcanoes of the 2 cordilleras and of the inter-andean valley plot at the junction of the two trends. These new data confirm previous observations made with the trace element and Sr-Nd systematics that suggested marked differences between the two cordilleras ([1], [3], [4]), and allow us to go forward distinguishing the back-arc. In addition, we are able to test the influence of Carnegie ridge on magma geochemistry, which is still debated. Altogether, Sr-Nd-Pb isotope variations require three different magmatic sources: (1) an unradiogenic component, represented by back-arc magmas, which may correspond to the mantle source; (2) an upper crustal radiogenic component, expressed in Eastern cordillera magmas and (3) a third component (low 87Sr/86Sr, radiogenic Nd-Pb isotopes), represented by some Western Cordillera magmas, which could either be an unradiogenic, immature oceanic basement or a slab influence. [1] Hidalgo et al., Lithos 132-133 (2012), 180-192 [2] Samaniego et al., Contrib. Mineral. Petrol. 160 (2010), 239-260 [3] Chiaradia et al., Contrib. Mineral. Petrol. 158 (2009), 563-588 [4] Schiano et al., Contrib. Mineral. Petrol. 160 (2010), 297-312

Evidence for a Late Reducing Event in IAB-Silicate Inclusions

NASA Astrophysics Data System (ADS)

Seckendorff, V. V.; O'Neill, H. St. C.; Zipfel, J.; Palme, H.

1992-07-01

Coexisting orthopyroxene (opx) and olivine (ol) in silicate inclusions of IAB-iron meteorites have different Fe/(Fe+Mg) ratios. Ferrosilite (fs) contents of opx are higher than fayalite contents (fa) of ol (e.g., Bunch and Keil 1970). Non-ideal solid solution of fs in opx and/or fa in ol is generally assumed. We reinvestigated the equilibrium Fe-Mg distribution between coexisting ol+opx in the system MgO-FeO-SiO2 (von Seckendorff and O'Neill 1992). Reversal experiments at high- Mg compositions were performed from 900 to 1600 degrees C at 16 and 20 kbar using a barium borosilicate flux. The data could be fitted to a simple thermodynamic model with ol and opx treated as regular solutions and this model was found to describe satisfactorily the literature data extending down to 700 degrees C. For Fe/(Fe+Mg) between 0.05 to 0.15 we find KD^ol-opx close to one from 1600 to 700 degrees C, virtually independent of pressure and temperature. Fig. 1 shows experimental results at the Mg-rich end. Error bars mark 1-sigma standard deviations. Ol is in all cases more Fe-rich than coexisting opx, except for a single run at 1000 degrees C that probably did not reach equilibrium because of slow reaction kinetics. Two calculated distribution curves (1300, 700 degrees C at 16 kbar) lie close together indicating the absence of any significant temperature dependence of the exchange reaction at the Mg- rich end of the system. IAB-silicate inclusions plot outside the range of experimental data (Fig. 1). Although some previous models for Fe-Mg exchange between ol and opx (e.g., Sack 1980) extrapolate to KD<1 at temperatures near 500 degrees C, such models reproduce the experimental data (700 to 1600 degrees C) less well, than our updated model. In addition, temperatures at 500 degrees C are probably too low to allow Fe diffusion in opx. Two pyroxene equilibration temperatures of IAB-silicate inclusions are around 900-1000 degrees C suggesting a similar closure temperature for Fe diffusion in opx. Because of this and because of the essentially temperature-independent Fe-Mg distribution between ol and opx from 1600 to 700 degrees C, we conclude that the Fe-Mg distribution between ol and opx in IAB-silicate inclusion does not reflect thermodynamic equilibrium. As Fe-diffusion in ol is faster than in opx, redistribution of Fe in ol should have occurred at a temperature below the closure temperature for Fe-diffusion in opx. We suggest that FeO in ol was reduced to Fe metal by some species such as C, P, S, etc. A lower limit for the temperature of the reducing event is provided by Ca-zoning in ol, which develops below 650 degrees C (Kohler et al. 1991). Since strong FeO zoning in ol is absent, reduction of FeO in ol should have occurred above 650 degrees C, assuming similar diffusion coefficients for Ca and Fe in ol. References: Bunch T.E. and Keil K. (1970) Contrib. Mineral. Petrol. 25, 297-340. Kohler T., Palme H. and Brey G. (1991) N. Jb. Miner. Mh. 9, 423-431. Sack R.O. (1980) Contrib. Mineral. Petrol. 71, 257-269. v. Seckendorff V. and O'Neill H.St.C. (1992) Contr. Min. Petrol. (submitted).

Formation and metasomatism of continental lithospheric mantle in intra-plate and subduction-related tectonic settings

NASA Astrophysics Data System (ADS)

Ionov, Dmitri

2010-05-01

Our knowledge of the origin and evolution of the continental lithospheric mantle (CLM) remains fragmentary and partly controversial in spite of recent advances in petrologic, geochemical and geophysical studies of the deep Earth and experimental work. Debate continues on a number of essential topics, like relative contributions of partial melting, metasomatism and ‘re-fertilisation' as well as the timing, conditions and tectonic settings of those processes. These topics can be addressed by studies of ultramafic xenoliths in volcanic rocks which arguably provide the least altered samples of modern and ancient CLM. The subcontinental lithosphere is thought to be a mantle region from which melts have been extracted, thus making the lithosphere more refractory. Melting degrees can be estimated from Al contents while the depth of melt extraction can be assessed from Al-Fe (Mg#) relations in unmetasomatized melting residues in comparison with experimental data, e.g. [1]. High silica and opx in the residues may indicate melting in water-rich conditions. High-precision Mg# and Mn for olivine may constrain degrees and conditions of partial melting and/or metasomatism, tectonic settings, modal compositions (e.g. presence of garnet) and equilibration conditions of mantle peridotites [2]. These estimates require both adequate sampling and high-quality major element and modal data; sampling and analytical uncertainties in published work may contribute substantially to chemical heterogeneities (and different origins) inferred for CLM domains [3]. Very fertile peridotite xenolith suites are rare worldwide [3]. They were initially viewed as representing mantle domains that experienced only very small degrees of melt extraction but are attributed by some workers to ‘refertilization' of refractory mantle by percolating asthenospheric melts. Such alternative mechanisms might be valid for some rare hybrid and Fe-enriched peridotites but they fail to comprehensively explain modal, major and trace element and isotope compositions of fertile lherzolites and thus cannot provide viable alternatives to the concept of melt extraction from pristine mantle as the major mechanism of CLM formation. Published data on xenoliths from andesitic volcanoes and on supra-subduction oceanic peridotites [4] show that the most common rocks in mantle wedge lithosphere are highly refractory harzburgites characterized by a combination of variable but generally high modal opx (18-30%) with very low modal cpx (1.5-3%). At a given olivine (or MgO) content, they have higher opx and silica, and lower cpx, Al and Ca contents than normal refractory peridotite xenoliths in continental basalts; the Mg-Si and Al-Si trends in those rocks resemble those in cratonic peridotites. These features may indicate either fluid fluxing during melting in the mantle wedge or selective post-melting metasomatic enrichments in silica to transform some olivine to opx. High oxygen fugacities and radiogenic Os-isotope compositions in those rocks may be related to enrichments by slab-derived fluids, but these features are not always coupled with trace element enrichments or patterns commonly attributed to "subduction zone metasomatism" deduced from studies of arc volcanic rocks and experiments. The valuable insights provided by experimental work and xenolith case studies are difficult to apply to many natural peridotite series because late-stage processes commonly overlap the evidence for initial melting. References: [1] Herzberg C., J. Petrol. 45: 2507 (2004). [2] Ionov D. & Sobolev A., GCA 72 (S1): A410 (2008). [3] Ionov D., Contrib. Miner. Petrol. (2007) [4] Ionov D., J. Petrol. doi: 10.1093/petrology/egp090 (2010)

Bioethanol from poplar: a commercially viable alternative to fossil fuel in the European Union.

PubMed

Littlewood, Jade; Guo, Miao; Boerjan, Wout; Murphy, Richard J

2014-01-01

The European Union has made it a strategic objective to develop its biofuels market in order to minimize greenhouse gas (GHG) emissions, to help mitigate climate change and to address energy insecurity within the transport sector. Despite targets set at national and supranational levels, lignocellulosic bioethanol production has yet to be widely commercialized in the European Union. Here, we use techno-economic modeling to compare the price of bioethanol produced from short rotation coppice (SRC) poplar feedstocks under two leading processing technologies in five European countries. Our evaluation shows that the type of processing technology and varying national costs between countries results in a wide range of bioethanol production prices (€0.275 to 0.727/l). The lowest production prices for bioethanol were found in countries that had cheap feedstock costs and high prices for renewable electricity. Taxes and other costs had a significant influence on fuel prices at the petrol station, and therefore the presence and amount of government support for bioethanol was a major factor determining the competitiveness of bioethanol with conventional fuel. In a forward-looking scenario, genetically engineering poplar with a reduced lignin content showed potential to enhance the competitiveness of bioethanol with conventional fuel by reducing overall costs by approximately 41% in four out of the five countries modeled. However, the possible wider phenotypic traits of advanced poplars needs to be fully investigated to ensure that these do not unintentionally negate the cost savings indicated. Through these evaluations, we highlight the key bottlenecks within the bioethanol supply chain from the standpoint of various stakeholders. For producers, technologies that are best suited to the specific feedstock composition and national policies should be optimized. For policymakers, support schemes that benefit emerging bioethanol producers and allow renewable fuel to be economically competitive with petrol should be established. Finally, for researchers, better control over plant genetic engineering and advanced breeding and its consequential economic impact would bring valuable contributions towards developing an economically sustainable bioethanol market within the European Union.

Method for Derivatization and Detection of Chemical Weapons Convention Related Sulfur Chlorides via Electrophilic Addition with 3-Hexyne.

PubMed

Goud, D Raghavender; Pardasani, Deepak; Purohit, Ajay Kumar; Tak, Vijay; Dubey, Devendra Kumar

2015-07-07

Sulfur monochloride (S2Cl2) and sulfur dichloride (SCl2) are important precursors of the extremely toxic chemical warfare agent sulfur mustard and classified, respectively, into schedule 3.B.12 and 3.B.13 of the Chemical Weapons Convention (CWC). Hence, their detection and identification is of vital importance for verification of CWC. These chemicals are difficult to detect directly using chromatographic techniques as they decompose and do not elute. Until now, the use of gas chromatographic approaches to follow the derivatized sulfur chlorides is not reported in the literature. The electrophilic addition reaction of sulfur monochloride and sulfur dichloride toward 3-hexyne was explored for the development of a novel derivatization protocol, and the products were subjected to gas chromatography-mass spectrometric (GC-MS) analysis. Among various unsaturated reagents like alkenes and alkynes, symmetrical alkyne 3-hexyne was optimized to be the suitable derivatizing agent for these analytes. Acetonitrile was found to be the suitable solvent for the derivatization reaction. The sample preparation protocol for the identification of these analytes from hexane spiked with petrol matrix was also optimized. Liquid-liquid extraction followed by derivatization was employed for the identification of these analytes from petrol matrix. Under the established conditions, the detection and quantification limits are 2.6 μg/mL, 8.6 μg/mL for S2Cl2 and 2.3 μg/mL, 7.7 μg/mL for SCl2, respectively, in selected ion monitoring (SIM) mode. The calibration curve had a linear relationship with y = 0.022x - 0.331 and r(2) = 0.992 for the working range of 10 to 500 μg/mL for S2Cl2 and y = 0.007x - 0.064 and r(2) = 0.991 for the working range of 10 to 100 μg/mL for SCl2, respectively. The intraday RSDs were between 4.80 to 6.41%, 2.73 to 6.44% and interday RSDs were between 2.20 to 7.25% and 2.34 to 5.95% for S2Cl2 and SCl2, respectively.

TitaniQ in reverse: backing out the equilibrium solubility of titanium in quartz

NASA Astrophysics Data System (ADS)

Thomas, J. B.

2014-12-01

There is close agreement among three of the four experimental studies that have 'calibrated' the P-T dependencies of Ti-in-quartz solubility. New experiments were conducted to identify potential experimental disequilibrium, and determine which Ti-in-quartz solubility calibration is most accurate. Quartz and rutile were synthesized from SiO2- and TiO2saturated aqueous fluids in a forward-type experiment at 925°C and 10 kbar in a piston-cylinder apparatus. A range of crystal sizes was examined to determine if growth rate affected Ti incorporation in quartz. Cathodoluminescence (CL) images and electron microprobe measurements show that intercrystalline and intracrystalline variations in Ti concentrations are remarkably small regardless of crystal size. The average Ti-in-quartz concentration from the forward-type experiment is 392±1 ppm Ti, which is within 95% confidence interval of data from the 10 kbar isobar of Wark and Watson (2006) and Thomas et al. (2010). Quartz from the forward-type experiment was used as starting material for reversal-type experiments. The high-Ti quartz starting material was recrystallized at 925°C and 20 kbar to reduce the solubility of Ti in recrystallized quartz to the equilibrium solubility concentration of the reversed P-T condition. The 'dry' and 'wet' reversal experiments produced polycrystalline quartzites. Rutile occurs as inclusions in quartz, and as individual crystals dispersed along quartz/quartz grain boundaries. Quartz that recrystallized during the reversal-type experiment has substantially lower Ti concentrations than the quartz starting material because Ti solubility at 20 kbar is significantly lower than at 10 kbar. Dark cathodoluminescent quartz with low Ti concentrations shows that extensive quartz recrystallization occurred at the reversal P-T condition. The average Ti concentration in quartz from reversal experiments is 94±2 ppm Ti, which is within the 95% confidence interval of a linear fit to the 20 kbar data of Thomas et al. (2010). Thomas JB, Watson EB, Spear FS, Shemella FS, Nayak SK, Lanzirotti A (2010) Contrib Mineral Petrol 160:743-759 Wark DA, Watson EB (2006) Contrib Mineral Petrol 152:743-754

Effects of Fertile Mantle Compositional Variation and Spreading Rate Variation on the Working of Global Ocean Ridges

NASA Astrophysics Data System (ADS)

Niu, Y.; O'Hara, M. J.

2014-12-01

Mantle temperature variation, plate spreading rate variation and mantle compositional variation have been considered to be the three fundamental variables that govern the working of global ocean ridges [1]. An analysis demonstrates that mantle compositional variation exerts the primary control on ocean ridge processes; it determines (1) variation in both composition and mode of mantle mineralogy, (2) variation of mantle density, (3) variation of ridge axial depth, (4) source-inherited MORB compositional variation, (4) density-controlled variation in the amplitude of mantle upwelling, (5) apparent variation in the extent of melting, and (6) the correlated variation of MORB chemistry with ridge axial depth [2]. The above interpretations are reinforced by the updated MORB database [3]. The new database also confirms spreading rate control on the extent of melting as shown previously [4]. Mantle temperature variation could play a part, but its overstated role [3,5] results from a basic error (1) in treating ridge axial depth variation as evidence of mantle temperature variation by ignoring the intrinsic control of mantle composition, (2) in treating "mantle plume" influenced ridges (e.g., Iceland) as normal ridges of plate spreading origin, and (3) in treating low Vs at greater depths (> 300 km vs. < 200 km beneath ridges) beneath these "mantle plume" influenced ridges as evidence for hot ridge mantle. In order to understand the working of global ocean ridges, we must avoid plume-influenced ridges (e.g., in the vicinity of Iceland) and remove/average out data from such ridges. As a result, the correlations (e.g., between ridge axial depth, mantle low Vs anomaly, and some geochemical parameters) required for the interpretation of mantle temperature control all disappear. There is thus no evidence for large mantle temperature variation away from ridges influenced by "mantle plumes". References: [1] Niu et al., 2001, Earth Planet Sci. Lett., 186, 383-399; [2] Niu & O'Hara, 2008, J. Petrol., 49, 633-664; [3] Gale et al., 2014, J. Petrol, 55, 1051-1082; [4] Niu & Hékinian, 1997, Nature, 385, 326-329; [5] Dalton et al., 2014, Science, 334, 80-83; [6]Niu & Hékinian, 2004, In Oceanic Hotspots, Springer-Verlag, 285-307.

A comparative study of the elemental composition of the exhaust emissions of cars powered by liquefied petroleum gas and unleaded petrol

NASA Astrophysics Data System (ADS)

Lim, McKenzie C. H.; Ayoko, Godwin A.; Morawska, Lidia; Ristovski, Zoran D.; Jayaratne, E. Rohan; Kokot, Serge

Elements emitted from the exhausts of new Ford Falcon Forte cars powered by unleaded petrol (ULP) and liquefied petroleum gas (LPG) were measured on a chassis dynamometer. The measurements were carried out in February, June and August 2001, and at two steady state driving conditions (60 and 80 km h -1). Thirty seven elements were quantified in the exhaust samples by inductively coupled plasma mass spectrometry (ICPMS). The total emission factors of the elements from the exhausts of ULP cars were higher than those of LPG cars at both engine speeds even though high variability in the exhaust emissions from different cars was noted. The effect of the operating conditions such as mileage of the cars, engine speed, fuel and lubricating oil compositions on the emissions was studied. To investigate the effects of these conditions, multivariate data analysis methods were employed including exploratory principal component analysis (PCA), and the multi-criteria decision making methods (MCDM), preference ranking organization method for enrichment evaluation (PROMETHEE) and geometrical analysis for interactive aid (GAIA), for ranking the cars on the basis of the emission factors of the elements. PCA biplot of the complete data matrix showed a clear discrimination of the February, June and August emission test results. In addition, (i) platinum group elements (PGE) emissions were separated from each other in the three different clusters viz. Pt with February, Pd with June and Rh with August; (ii) the motor oil related elements, Zn and P, were particularly associated with the June and August tests (these vectors were also grouped with V, Al and Cu); and (iii) highest emissions of most major elements were associated with the August test after the cars have recorded their highest mileage. Extensive analysis with the aid of the MCDM ranking methods demonstrated clearly that cars powered by LPG outperform those powered by ULP. In general, cars tested in June perform better than those tested in August, which suggested that mileage was the key criterion of car performance on the basis of elemental emission factors.

Crustal contamination and crystal entrapment during polybaric magma evolution at Mt. Somma-Vesuvius volcano, Italy: Geochemical and Sr isotope evidence

USGS Publications Warehouse

Piochi, M.; Ayuso, R.A.; de Vivo, B.; Somma, R.

2006-01-01

New major and trace element analyses and Sr-isotope determinations of rocks from Mt. Somma-Vesuvius volcano produced from 25 ky BP to 1944 AD are part of an extensive database documenting the geochemical evolution of this classic region. Volcanic rocks include silica undersaturated, potassic and ultrapotassic lavas and tephras characterized by variable mineralogy and different crystal abundance, as well as by wide ranges of trace element contents and a wide span of initial Sr-isotopic compositions. Both the degree of undersaturation in silica and the crystal content increase through time, being higher in rocks produced after the eruption at 472 AD (Pollena eruption). Compositional variations have been generally thought to reflect contributions from diverse types of mantle and crust. Magma mixing is commonly invoked as a fundamental process affecting the magmas, in addition to crystal fractionation. Our assessment of geochemical and Sr-isotopic data indicates that compositional variability also reflects the influence of crustal contamination during magma evolution during upward migration to shallow crustal levels and/or by entrapment of crystal mush generated during previous magma storage in the crust. Using a variant of the assimilation fractional crystallization model (Energy Conservation-Assimilation Fractional Crystallization; [Spera and Bohrson, 2001. Energy-constrained open-system magmatic processes I: General model and energy-constrained assimilation and fractional crystallization (EC-AFC) formulation. J. Petrol. 999-1018]; [Bohrson, W.A. and Spera, F.J., 2001. Energy-constrained open-system magmatic process II: application of energy-constrained assimilation-fractional crystallization (EC-AFC) model to magmatic systems. J. Petrol. 1019-1041]) we estimated the contributions from the crust and suggest that contamination by carbonate rocks that underlie the volcano (2 km down to 9-10 km) is a fundamental process controlling magma compositions at Mt. Somma-Vesuvius in the last 8 ky BP. Contamination in the mid- to upper crust occurred repeatedly, after the magma chamber waxed with influx of new mantle- and crustal-derived magmas and fluids, and waned as a result of magma withdrawal and production of large and energetic plinian and subplinian eruptions. ?? 2005 Elsevier B.V. All rights reserved.

Techno-economic potential of bioethanol from bamboo in China

PubMed Central

2013-01-01

Background Bamboo is potentially an interesting feedstock for advanced bioethanol production in China due to its natural abundance, rapid growth, perennial nature and low management requirements. Liquid hot water (LHW) pretreatment was selected as a promising technology to enhance sugar release from bamboo lignocellulose whilst keeping economic and environmental costs to a minimum. The present research was conducted to assess: 1) by how much LHW pretreatment can enhance sugar yields in bamboo, and 2) whether this process has the potential to be economically feasible for biofuel use at the commercial scale. Pretreatments were performed at temperatures of 170-190°C for 10–30 minutes, followed by enzymatic saccharification with a commercial enzyme cocktail at various loadings. These data were then used as inputs to a techno-economic model using AspenPlus™ to determine the production cost of bioethanol from bamboo in China. Results At the selected LHW pretreatment of 190°C for 10 minutes, 69% of the initial sugars were released under a standardised enzyme loading; this varied between 59-76% when 10–140 FPU/g glucan of commercial enzyme Cellic CTec2 was applied. Although the lowest enzyme loading yielded the least amount of bioethanol, the techno-economic evaluation revealed it to be the most economically viable scenario with a production cost of $0.484 per litre (with tax exemption and a $0.16/litre subsidy). The supply-chain analysis demonstrated that bioethanol could be economically competitive with petrol at the pump at enzyme loadings up to 60 FPU/g glucan. However, in a prospective scenario with reduced government support, this enzyme loading threshold would be reduced to 30 FPU/g glucan. Conclusions Bioethanol from bamboo is shown to be both technically and economically feasible, as well as competitive with petrol in China. Alternative approaches to reduce bioethanol production costs are still needed however, to ensure its competitiveness in a possible future scenario where neither tax exemptions nor subsidies are granted to producers. These measures may include improving sugar release with more effective pretreatments and reduced enzyme usage, accessing low cost bamboo feedstock or selecting feedstocks with higher/more accessible cellulose. PMID:24286490

Antibacterial efficacy of the seed extracts of Melia azedarach against some hospital isolated human pathogenic bacterial strains

PubMed Central

Khan, Abdul Viqar; Ahmed, Qamar Uddin; Mir, M Ramzan; Shukla, Indu; Khan, Athar Ali

2011-01-01

Objective To investigate the antibacterial potential of the polar and non-polar extracts of the seeds of Melia azedarach (M. azedarach) L. (Meliaceae) against eighteen hospital isolated human pathogenic bacterial strains. Methods Petrol, benzene, ethyl acetate, methanol, and aqueous extracts at five different concentrations (1, 2, 5, 10 and 15 mg/mL) were evaluated. Disk diffusion method was followed to evaluate the antibacterial efficacy. Results All extracts of the seeds demonstrated significant antibacterial activity against tested pathogens. Among all extracts, ethyl acetate extract revealed the highest inhibition comparatively. The present study also favored the traditional uses reported earlier. Conclusions Results of this study strongly confirm that the seed extracts of M. azedarach could be effective antibiotics, both in controlling gram-positive and gram-negative human pathogenic infections. PMID:23569812

Encephalopathy and Neuropathy due to Glue, Paint Thinner, and Gasoline Sniffing in Trinidad and Tobago-MRI Findings.

PubMed

Ramcharan, Kanterpersad; Ramesar, Amrit; Ramdath, Moshanti; Teelucksingh, Joel; Gosein, Maria

2014-01-01

A 29-year-old male petrol station pump attendant was admitted with ataxia and clinical evidence of a sensorimotor polyneuropathy which developed over the preceding 3 months. He had cognitive dysfunction, hearing loss, and cerebellar clinical abnormalities that came on slowly over the three years. He had a fifteen-year history of sniffing mostly glue, occasionally paint thinners, and, in the recent two years, gasoline. Magnetic resonance brain imaging showed abnormalities of the cerebral cortex, cerebral white matter, corpus callosum, hippocampus, brainstem and cerebellar atrophy, hypointensities of basal ganglia, red nuclei, and substantia nigra as previously described in toluene sniffing. Abstinence for six months led to partial clinical improvement. Clinicians need to be aware of this preventable entity which has peculiar radiological findings which are being increasingly accepted as typical.

Encephalopathy and Neuropathy due to Glue, Paint Thinner, and Gasoline Sniffing in Trinidad and Tobago-MRI Findings

PubMed Central

Ramcharan, Kanterpersad; Ramesar, Amrit; Ramdath, Moshanti; Teelucksingh, Joel; Gosein, Maria

2014-01-01

A 29-year-old male petrol station pump attendant was admitted with ataxia and clinical evidence of a sensorimotor polyneuropathy which developed over the preceding 3 months. He had cognitive dysfunction, hearing loss, and cerebellar clinical abnormalities that came on slowly over the three years. He had a fifteen-year history of sniffing mostly glue, occasionally paint thinners, and, in the recent two years, gasoline. Magnetic resonance brain imaging showed abnormalities of the cerebral cortex, cerebral white matter, corpus callosum, hippocampus, brainstem and cerebellar atrophy, hypointensities of basal ganglia, red nuclei, and substantia nigra as previously described in toluene sniffing. Abstinence for six months led to partial clinical improvement. Clinicians need to be aware of this preventable entity which has peculiar radiological findings which are being increasingly accepted as typical. PMID:25045557

Energy use and taxation policy in the New Zealand car fleet

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1984-02-01

The report describes the composition of the New Zealand car fleet and the relationship between design factors, fleet composition, vehicle useage and fuel consumption. The indirect energy content of the vehicle and roadway are discussed. Existing and potential Government policy instruments for promoting fuel economy in the car fleet are discussed and evaluated. The report conclusions favor flat rate sales tax on vehicles regardless of engine size together with an appropriate level of petrol tax in preference to taxation that varies with vehicle size or engine capacity. A review of hire purchase regulations is proposed. Prior to publication of thismore » report the Industries Development Commission Plan for the motor vehicle industry was released which proposes changes to the tariff, taxation and credit purchase regime applying to motor vehicles. These changes are summarized.« less

Potential dangers of accelerant use in arson.

PubMed

Heath, Karen; Kobus, Hilton; Byard, Roger W

2011-02-01

Accelerant-enhanced combustion often characterizes a fire that has been deliberately set to disguise a murder scene or to destroy property for insurance purposes. The intensity and rapidity of spread of fires where accelerants have been used are often underestimated by perpetrators who may sustain heat-related injuries. The case of a 49-year-old male who was using gasoline (petrol) as an accelerant is reported to demonstrate another danger of this type of activity. After ignition, an explosion occurred that destroyed the building and caused the death of the victim who was crushed beneath a rear wall of the commercial premises. Gasoline vapour/air mixtures are extremely volatile and may cause significant explosions if exposed to flame. Given the potential danger of explosion, arsonists using accelerants do so at significant risk to themselves and to others in the vicinity. Copyright © 2011 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

The Paul-Emile Victor group. to the rescue of the sea (in French)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

The Paul-Emile Victor Group, which includes P. E. Victor, J. Auriol, A. Bombard, J. Y. Consteau, J. Debat, L. Leprince-Ringuet, and H. Tazieff, was formed to protect man and his environment, and for about a year has been prepared to deal with problems caused by marine pollution. Eight industrial firms, including the Compagnie Francaise des Petroles, supply chemical, financial, and scientific assistance. The Service d'Action and d'Assistance Marine d'Urgence and de Recherche (SAMUR), has three functions: corrective action, research and prevention, and education; it is divided into two sections: one comprising several rapid-action units (UNIR), and the other constituting amore » center for marine bioecological study and research (''cerber-mer''). The UNIR includes professional divers, pollution-control technicians, and biologists and goes into action immediately. The ''cerber-mer'' section will constitute a 24 hr information-exchange center for all of Europe.« less

Epidemiology of burns due to domestic flammable agents.

PubMed

Pegg, S P; Beecham, L; Dore, N; Hrdlicka, D; Hukins, C

1990-04-01

An analysis of the epidemiological factors relating to domestic flammable agents has shown that 17.7 per cent of admissions over a 5-year period were involved in domestic flammable injuries; 87.7 per cent of the patients were male, with 38.9 per cent being young males between 12 and 19 years old. Petrol and diesel accounted for 56.8 per cent of the burns and the average body surface area burned was 17.7 per cent. Most commonly the face, hands and limbs were burned, and the average length of stay was 18.25 days, 69.2 per cent of the burns were due to human error and were thus potentially preventable, 21.2 per cent had predisposing conditions with 8.9 per cent being due to alcohol. It was considered that the strategies to prevent these burns injuries should be aimed particularly at young males.

Trends and sources for heavy metals in urban atmosphere

NASA Astrophysics Data System (ADS)

Kemp, Kåre

2002-04-01

The concentrations of a number of heavy metals in the air in three Danish cities have been measured by means of PIXE for more than two decades. The well-known capability of PIXE for fast and efficient analysis of aerosol samples has been employed for analysis of daily samples from several sites during the whole period. The main sources are traffic, domestic heating and long-range transport. Source apportionment and trends for single metals are assessed by means of simple statistical methods. The most striking change has occurred for the Pb concentration, which is reduced by almost a factor of 100 following the reduction of the Pb content in petrol. The main source of Cu, Cr and Zn is the traffic. The concentrations of these elements have been slightly increasing. The concentrations for most of the other heavy metals, which originate mainly from sources outside the cities, have been decreasing.

Environmental lead exposure to toll booth workers in Hong Kong

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tan, T.C.; Wong, L.T.L.; Lam, C.W.K.

1988-01-01

A survey of workers in the Lion Rock Tunnel toll booths was conducted, as they were regarded as a high risk group in lead exposure due to high density of vehicular traffic. The exposure of the workers to lead was determined by continuous sapling of air around the breathing zone of workers inside the booths. Blood lead concentration of 50 workers showed a mean of 0.65 {mu}mol/L and the mean urine lead concentration was 0.14 {mu}mol/L. Other tests, such as urinary amino-levulinic acid (ALA), erythrocyte zinc protoporphyrin (ZnPP) and hemoglobin concentration (Hb), were also preformed. The blood lead concentrations andmore » other biological parameters of the toll-booth workers were acceptable and may be attributed to the recent legislation to lower the lead content in petrol and to the good preventive measures taken by the management.« less

Molecular application for identification of polycyclic aromatic hydrocarbons degrading bacteria (PAHD) species isolated from oil polluted soil in Dammam, Saud Arabia.

PubMed

Ibrahim, Mohamed M; Al-Turki, Ameena; Al-Sewedi, Dona; Arif, Ibrahim A; El-Gaaly, Gehan A

2015-09-01

Soil contamination with petroleum hydrocarbon products such as diesel and engine oil is becoming one of the major environmental problems. This study describes hydrocarbons degrading bacteria (PHAD) isolated from long-standing petrol polluted soil from the eastern region, Dammam, Saudi Arabia. The isolated strains were firstly categorized by accessible shape detection, physiological and biochemistry tests. Thereafter, a technique established on the sequence analysis of a 16S rDNA gene was used. Isolation of DNA from the bacterial strains was performed, on which the PCR reaction was carried out. Strains were identified based on 16S rDNA sequence analysis, As follows amplified samples were spontaneously sequenced automatically and the attained results were matched to open databases. Among the isolated bacterial strains, S1 was identified as Staphylococcus aureus and strain S1 as Corynebacterium amycolatum.

[Emission of volatile components in carpenter's kumylotox into air].

PubMed

Jodynis-Liebert, J; Kiejnowska, M

1991-01-01

Study was made of Carpenter's Kumylotox, a fungicidal preparation containing: p-cumylphenol, dibutyl phthalate, machine oil, chloroparaffin, a 15% solution of ker-1500 rubber in painter's naphta, and petrol for pastas. The preparation was applied onto boards placed in an experimental chamber at 1-week intervals. In air of the chamber, dibutyl phthalate and p-cumylphenol were determined quantitatively by gas chromatography. The presence of hydrocarbons was recorded by the same method, without quantitative determination. Analyses were continued until the disappearance of the investigated from air. It was found that already after 2 weeks the p-cumylphenol level dropped below the allowable concentration amounting to 0.015 mg/dm3. The dibutyl phthalate level decreased to the allowable concentration (0.05 mg/m3) only after 9 weeks of board ageing. According to analysis by the GC-MS method, aromatic hydrocarbons disappeared from the chamber's air already after 5 weeks, and the remaining hydrocarbons--after 9 weeks.

Design of a fifth generation air superiority fighter

NASA Astrophysics Data System (ADS)

Atique, Md. Saifuddin Ahmed; Barman, Shuvrodeb; Nafi, Asif Shahriar; Bellah, Masum; Salam, Md. Abdus

2016-07-01

Air Superiority Fighter is considered to be an effective dogfighter which is stealthy & highly maneuverable to surprise enemy along with improve survivability against the missile fire. This new generation fighter aircraft requires fantastic aerodynamics design, low wing loading (W/S), high thrust to weight ratio (T/W) with super cruise ability. Conceptual design is the first step to design an aircraft. In this paper conceptual design of an Air Superiority Fighter Aircraft is proposed to carry 1 crew member (pilot) that can fly at maximum Mach No of 2.3 covering a range of 1500 km with maximum ceiling of 61,000 ft. Payload capacity of this proposed aircraft is 6000 lb that covers two advanced missiles & one advanced gun. The Air Superiority Fighter Aircraft was designed to undertake all the following missions like: combat air petrol, air to air combat, maritime attack, close air support, suppression, destruction of enemy air defense and reconnaissance.

[Chronic CO poisoning. Use of generator gas during the second world war and recent research].

PubMed

Tvedt, B; Kjuus, H

1997-06-30

The consequences of long-lasting and low-grade exposure to carbon monoxide are a matter of debate. During the second world war, lack of petrol led to widespread use of wood as fuel (generator gas vehicles), especially in the Nordic countries. This caused many cases of "acute" or "chronic" carbon monoxide poisoning. Typical symptoms of "chronic poisoning" were headache, dizziness and tiredness. Usually the symptoms disappeared after some weeks or month, but in some patients probably became permanent. The experiences from the generator gas era are now almost forgotten, and chronic carbon monoxide poisoning is easily overlooked. The authors describe two cases of such poisoning. A crane driver at a smelting works developed permanent symptoms after twenty years of exposure. A faulty oil-fired central heating system caused long-lasting symptoms in four members of a family.

A comparative evaluation on the emission characteristics of ceramic and metallic catalytic converter in internal combustion engine

NASA Astrophysics Data System (ADS)

Leman, A. M.; Jajuli, Afiqah; Rahman, Fakhrurrazi; Feriyanto, Dafit; Zakaria, Supaat

2017-09-01

Enforcement of a stricter regulation on exhaust emission by many countries has led to utilization of catalytic converter to reduce the harmful pollutant emission. Ceramic and metallic catalytic converters are the most common type of catalytic converter used. The purpose of this study is to evaluate the performance of the ceramic and metallic catalytic converter on its conversion efficiency using experimental measurement. Both catalysts were placed on a modified exhaust system equipped with a Mitshubishi 4G93 single cylinder petrol engine that was tested on an eddy current dynamometer under steady state conditions for several engine speeds. The experimental results show that the metallic catalytic converter reduced a higher percentage of CO up to 98.6% reduction emissions while ceramic catalytic converter had a better reduction efficiency of HC up to 85.4% and 87.2% reduction of NOx.

Resource-saving accommodation of the enterprises of service for travelling by car in the context of sustainable development of territories

NASA Astrophysics Data System (ADS)

Popov, Vyacheslav; Ermakov, Alexander; Mukhamedzhanova, Olga

2017-10-01

Sustainable development of trailering in Russia needs energy efficient and environmentally safe localization of the providing infrastructure which includes customer services, such as enterprises of hospitality (campings). Their rational placement minimizes the fuel consumption by vehicles, but also emissions of harmful substances into the atmosphere. The article presents rational localization of the sites for the construction of such enterprises using the MATLAB program. The program provides several levels of the task solution: from the total characteristic of the territory (the head interface) to the analysis of the possibility of forwarding charges on visit of the enterprises of car service (petrol station, automobile spare parts shops, car repair enterprises, cafe, campings and so on). The program offered implementation of the optimization by the criterion of decrease in energy costs allows to establish the preferable fields of their rational localization.

The curious case of the date of introduction of leaded fuel to Australia: Implications for the history of Southern Hemisphere atmospheric lead pollution

NASA Astrophysics Data System (ADS)

Cook, D. E.; Gale, S. J.

By comparison with the Northern Hemisphere, the history of atmospheric lead pollution in the Southern Hemisphere is still poorly understood. Until recently, the main source of atmospheric lead fallout in the Southern Hemisphere was tetraethyl lead from motor fuel and for most of the 20th century the most important single source of this pollutant was Australia. Yet there is little agreement over when leaded fuel made its first appearance in Australia. Reported dates range from the early 1920s to the late 1940s. A study of oil company advertisements and reports in motoring and oil company journals shows that leaded petrol first became available in Australia in August 1932. This date is important both for the reconstruction of lead pollution histories and in the use of lead stratigraphies to determine chronology.

Identification and Discrimination of Brands of Fuels by Gas Chromatography and Neural Networks Algorithm in Forensic Research

PubMed Central

Ugena, L.; Moncayo, S.; Manzoor, S.; Rosales, D.

2016-01-01

The detection of adulteration of fuels and its use in criminal scenes like arson has a high interest in forensic investigations. In this work, a method based on gas chromatography (GC) and neural networks (NN) has been developed and applied to the identification and discrimination of brands of fuels such as gasoline and diesel without the necessity to determine the composition of the samples. The study included five main brands of fuels from Spain, collected from fifteen different local petrol stations. The methodology allowed the identification of the gasoline and diesel brands with a high accuracy close to 100%, without any false positives or false negatives. A success rate of three blind samples was obtained as 73.3%, 80%, and 100%, respectively. The results obtained demonstrate the potential of this methodology to help in resolving criminal situations. PMID:27375919

Characterisation of particle emissions from the driving car fleet and the contribution to ambient and indoor particle concentrations

NASA Astrophysics Data System (ADS)

Palmgren, Finn; Wåhlin, Peter; Kildesø, Jan; Afshari, Alireza; Fogh, Christian L.

The population is mainly exposed to high air pollution concentrations in the urban environment, where motor vehicle emissions constitute the main source of fine and ultrafine particles. These particles can penetrate deep into the respiratory system, and studies indicate that the smaller the particle, the larger the health impacts. The chemical composition, surface reactivity and physical properties are also important. However, the knowledge about chemical and physical properties of particles and the temporal and spatial variability of the smallest particles is still very limited. The present study summarises the first results of a larger project with the aims to improve the knowledge. The concentration and the emissions of ultrafine particles from petrol and diesel vehicles, respectively, have been quantified using Scanning Mobility Particle Sizer of ultrafine particles in the size range 6-700 nm and routine monitoring data from urban streets and urban background in Denmark. The quantification was carried out using receptor modelling. The number size distributions of petrol and diesel emissions showed a maximum at 20-30 nm and non-traffic at ≈100 nm. The contribution of ultrafine particles from diesel vehicles is dominating in streets. The same technique has been applied on PM 10, and ≈50% contribution from non-traffic. The technique has also been introduced in relation to elemental and organic carbon, and the first data showed strong correlation between traffic pollution and elemental carbon. The outdoor air quality has a significant effect on indoor pollution levels, and we spend most of the time indoors. Knowledge about the influence of ambient air pollution on the concentrations in the indoor environment is therefore crucial for assessment of human health effects of traffic pollution. The results of our studies will be included in air quality models for calculation of human exposure. Preliminary results from our first campaign showed, that the deposition rate of particles in the apartment is negligible in the particle size range 100-500 nm. In the size range below 100 nm the deposition rate increases with decreasing particle diameter to a value of approximately 1 h -1 at 10 nm. The penetration efficiency shows a maximum of 60% at 100 nm. More detailed studies of exchange of particles in outdoor/indoor air and the transformation are planned to take place during three next campaigns.

Two high resolution terrestrial records of atmospheric Pb deposition from New Brunswick, Canada, and Loch Laxford, Scotland.

PubMed

Kylander, Malin E; Weiss, Domink J; Kober, Bernd

2009-02-15

Environmental archives like peat deposits allow for the reconstruction of both naturally and anthropogenically forced changes in the biogeochemical cycle of Pb as well as the quantification of past and present atmospheric Pb pollution. However, records of atmospheric Pb deposition from pre-industrial times are lacking. In a publication by Weiss et al. [Weiss, D., Shotyk, W., Boyle, E.A., Kramers, J.D., Appleby, P.G., Cheburkin, A.K., Comparative study of the temporal evolution of atmospheric lead deposition in Scotland and eastern Canada using blanket peat bogs. Sci Total Environ 2002;292:7-18]. Pb isotopes data measured by Q-ICP-MS and TIMS, concentration and enrichment data was presented for sites in eastern Canada (PeW1) and northwestern Scotland (LL7c), dating to 1586 A.D and 715 A.D., respectively. Here these same cores are re-analysed for Pb isotopes by MC-ICP-MS thereby acquiring 204Pb data and improving on the original data in terms of resolution and temporal coverage. Significant differences were found between the Q-ICP-MS/TIMS and MC-ICP-MS measurements, particularly at PeW1. These discrepancies are attributed to the problematic presence of organic matter during sample preparation and analysis complicated by the heterogeneity of the organic compounds that survived sample preparation steps. The precision and accuracy of Pb isotopes in complex matrices like peat is not always well estimated by industrial standards like NIST-SRM 981 Pb. Lead pollution histories at each site were constructed using the MC-ICP-MS data. The entire LL7c record is likely subject to anthropogenic additions. Contributions from local mining were detected in Medieval times. Later, coal use and mining in Scotland, Wales and England became important. After industrialization (ca. 1885 A.D.) contributions from Broken Hill type ores and hence, leaded petrol, dominate atmospheric Pb signatures right up to modern times. At PeW1 anthropogenic impacts are first distinguishable in the late 17th century with the mining and use of local coal. After industrialization (ca. 1810 A.D.), coal and petrol are the main Pb sources. A comprehensive estimate of the natural atmospheric background 206Pb/207Pb signature in eastern Canadian aerosols is made with a value of approximately 1.19.

Hydrocarbon emission fingerprints from contemporary vehicle/engine technologies with conventional and new fuels

NASA Astrophysics Data System (ADS)

Montero, Larisse; Duane, Matthew; Manfredi, Urbano; Astorga, Covadonga; Martini, Giorgio; Carriero, Massimo; Krasenbrink, Alois; Larsen, B. R.

2010-06-01

The present paper presents results from the analysis of 29 individual C 2-C 9 hydrocarbons (HCs) specified in the European Commission Ozone Directive. The 29 HCs are measured in exhaust from common, contemporary vehicle/engine/fuel technologies for which very little or no data is available in the literature. The obtained HC emission fingerprints are compared with fingerprints deriving from technologies that are being phased out in Europe. Based on the total of 138 emission tests, thirteen type-specific fingerprints are extracted (Mean ± SD percentage contributions from individual HCs to the total mass of the 29 HCs), essential for receptor modelling source apportionment. The different types represent exhaust from Euro3 and Euro4 light-duty (LD) diesel and petrol-vehicles, Euro3 heavy-duty (HD) diesel exhaust, and exhaust from 2-stroke preEuro, Euro1 and Euro2 mopeds. The fuels comprise liquefied petroleum gas, petrol/ethanol blends (0-85% ethanol), and mineral diesel in various blends (0-100%) with fatty acid methyl esters, rapeseed methyl esters palm oil methyl esters, soybean oil methyl or sunflower oil methyl esters. Type-specific tracer compounds (markers) are identified for the various vehicle/engine/fuel technologies. An important finding is an insignificant effect on the HC fingerprints of varying the test driving cycle, indicating that combining HC fingerprints from different emission studies for receptor modelling purposes would be a robust approach. The obtained results are discussed in the context of atmospheric ozone formation and health implications from emissions (mg km -1 for LD and mopeds and mg kW h -1 for HD, all normalised to fuel consumption: mg dm -3 fuel) of the harmful HCs, benzene and 1,3-butadiene. Another important finding is a strong linear correlation of the regulated "total" hydrocarbon emissions (tot-HC) with the ozone formation potential of the 29 HCs (ΣPO 3 = (1.66 ± 0.04) × tot-RH; r2 = 0.93). Tot-HC is routinely monitored in emission control laboratories, whereas C 2-C 9 are not. The revealed strong correlations broadens the usability of data from vehicle emission control laboratories and facilitates the comparison of the ozone formation potential of HCs in exhaust from of old and new vehicle/engine/fuel technologies.

Mantle metasomatism vs host magma interaction at Sal Island (Cape Verde Archipelago)

NASA Astrophysics Data System (ADS)

Bonadiman, Costanza; Coltorti, Massimo; Beccaluva, Luigi; Siena, Franca

2010-05-01

The Cape Verde Islands lie in the Atlantic Ocean off West Africa, in a clearly oceanic setting. Xenoliths from Miocene (16Ma) neck in the northern part of Sal Island bear extensive evidence of metasomatic reactions, characterized by secondary parageneses (ol+sp+cpx+glass+K-feld) around primary orthopyroxene, clinopyroxenes and spinel. These textures are commonly observed in many xenolith populations worldwide, independently of the nature of the carrying alkaline magma (i.e. basalts, lamproitic or kimberlitic melt). The interpretation as a product of metasomatism has been recently put under discussion by Shaw et al. (2006) and Shaw & Dingwell (2008) who consider that most of these textures are imposed on the xenoliths during magma transport and/or residence in a magma chamber. This contribution aims at emphasizing the criteria which allow to discriminate between the metasomatic and host magma infiltration processes, reinforcing the concept and validity of metasomatism within the mantle. To pursue this, various petrographic and geochemical criteria from a selected well-studied suite of mantle xenoliths that clearly testify for an interaction of the peridotites with silicate melts at depth (metasomatised samples) or during the transport to the surface (host basalt infiltration samples) will be presented. Few pristine samples (two lherzolites and one harburgite) devoid of any textural evidences for basaltic infiltration or metasomatic processes were also used for comparison. The metasomatised samples are constituted by three lherzolites and one harzburgite whose metasomatic textures include glassy pools, patches or veins with secondary parageneses made up of ol, cpx, sp and K-feld or spongy rims and sieved crystals of pyroxenes and spinels. The infiltrated samples are represented by one lherzolite and one harzburgite cut by glassy veinlets filled with euhedral to subeuhedral ol + plag + magnetites crystallites. In the metasomatic samples the secondary olivines at similar mg# [Mg/(Mg + Fe) • 100 = 86.7 - 91.5).] tend to have higher Ca and lower Ni contents with respect to the primary unmetasomatised grains. Feldspar are characterized by very high K2O content (up to 10.50 wt%, Bonadiman et al., 2005) very peculiar for mantle environment even for continental settings. Glasses are rather homogeneous in composition and characterized by relatively high SiO2 (55.73-67.13 wt %), Al2O3 (14.33-21.4 wt %) and alkali contents (Na2O 2.49-7.14 wt %; K2O 5.50-8.78 wt %). Their compositions are similar to those of most mantle xenolith glasses worldwide, apart from the exceptionally high K2O contents, which have never been found in oceanic settings before and have rarely been matched even in continental xenoliths. In the infiltrated samples secondary olivine are distinctively enriched in FeO relative to those primary and secondary of the peridotite assemblage. NiO -Fo composition of these crystallites are compatible with those calculated for olivine in equilibrium with a progressively fractionated melt. Feldspars are Ca-rich plagioclase (An 75)). Glasses of the infiltrated samples are systematically richer in FeO (and MgO), TiO2 and depleted in K2O with respect those of metasomatised samples. Hf and Nd isotopic analyses on separated cpxs from pristine and metasomatized samples are distinctly higher of those recorded both southern and northern lavas of Cape Verde Archipelago (Martins et al., 2010) [Xenoliths: 176Hf/177Hf 0.283038- 0.2831012; 143Nd/144Nd 0.512837 to 0.512955. Lavas: 176Hf/177Hf=0.28284-0.28297; 43Nd/144Nd=0.51261-0.51287]. References: Bonadiman et al. (2005), J. Petrol. 46, 2465-2493 Martins et al. (2010), Mineralogy & Petrology, OnlineFirst. Shaw & Dingwell (2008). Contrib. Mineral. Petrol., 155, 199-214 Shaw et al. (2006). Contrib. Mineral. Petrol., 151,681-697.

Trace element mobility at the slab-mantle interface: constraints from "hybrid

NASA Astrophysics Data System (ADS)

Marocchi, M.; Tropper, P.; Mair, V.; Bargossi, G. M.; Hermann, J.

2009-04-01

Subduction mélanges and hybrid rocks are considered, together with mafic rocks, metasediments and serpentinite as an important volatile-bearing portion of subducting slabs (cf. Spandler et al., 2008 and references therein; Miller et al., 2009). In particular, metasomatic rocks occurring in exhumed HP mélanges have recently attracted growing interest for two main reasons: i) metasomatic rocks forming at the interface between ultramafic and crustal rocks of subducting slabs constitute new bulk compositions which can affect the redistribution of major and trace elements and modify the composition of slab fluids moving to the mantle wedge and ii) these mineral assemblages, consisting mainly of hydrous phases can potentially store and transport water at great depth in subduction zones. Ultramafic rocks belonging to the Hochwart peridotite (Ulten Zone, central-eastern Italian Alps) preserve a series of metasomatic mineral zones generated by infiltration of hydrous fluids/melts, which occurred at the gneiss-peridotite interface (Tumiati et al., 2007; Marocchi et al., 2009). The peridotite body of Mt. Hochwart represents an almost unique occurrence where subduction-related mantle metasomatism can be studied on an outcrop scale. The ultramafic body consists of metaperidotites exposed as a hectometre-size lens along a steep gully, associated to monomineralic zones that developed at the contact between the peridotite body and the garnet-bearing gneiss country rocks. The formation of the metasomatic zones composed exclusively of hydrous phases involved extensive H2O-metasomatism as already documented for the Ulten peridotites (Scambelluri et al., 2006; Marocchi et al., 2007). Whole-rock geochemistry and trace element composition of hydrous phases (phlogopite and amphibole) in different metasomatic zones indicate mobility of many elements, including elements such as Ta, which are considered to have scarce mobility in fluids. Trace element composition of accessory minerals in the phlogopite-rich zone suggests that the trace element signature of subduction zone fluids may be fractionated in this zone. The progressive depletion in some trace elements (LREE and LILE) and enrichment in Li from the gneiss towards the peridotite suggests a strong influence of bulk composition on the trace element budget of hydrous minerals. Since these metasomatic zones can be representative of the processes occurring at the slab-mantle interface, we can infer that metasomatic reactions between slab-derived fluids and ultramafic mantle wedge will follow a specific series of reactions and create mineral zones similar to those observed in this study. Despite the mobility of many elements, in the trace element profiles for amphibole and phlogopite across the different zones, we observe a rapid decrease even of the "fluid mobile" element contents within the reaction zone. With the exception of Li, we assist to an abrupt decrease of most of trace element concentrations going towards the peridotite side contact. Thus, according to the present study, it is not likely that the "crustal trace element signature" (i.e. LILE and LREE-enriched) could be able to travel far into the mantle. Our results further favour the evidence that the primary composition of subduction zone fluids reaching the source region of arc magmas is substantially modified by metasomatic reactions occurring in the mantle wedge. Furthermore, we underline that metasomatic rocks such as those observed at Mt. Hochwart are potentially able to transport H2O and other trace elements to greater depths in subduction zones. References: Marocchi M, Hermann J, Morten L (2007)-Lithos 99: 85-104. Marocchi M, Mair V, Tropper P, Bargossi GM (2009)-Mineral Petrol, in press Miller DP, Marschall RH, Schumacher JC (2009)- Lithos 107: 53-67. Scambelluri M, Hermann J, Morten L, Rampone E (2006)- Contrib Mineral Petrol 151:372-394. Spandler CJ, Hermann J, Faure K, Mavrogenes JA, Arculus RJ (2008)- Contrib Mineral Petrol 155: 181-198. Tumiati S, Godard G, Martin S, Klőtzli U, Monticelli D (2007)- Lithos 94: 148-167.

Composition of the lithospheric mantle in the Siberian craton : New constraints from fresh peridotites from the Udachnaya-East Kimberlite

NASA Astrophysics Data System (ADS)

Doucet, Luc-Serge; Ionov, Dmitri A.; Ashchepkov, Igor

2010-05-01

Peridotite xenoliths from the Udachnaya kimberlite pipe represent the major source of lithospheric mantle samples beneath central Siberian craton. An important problem with the availble data [1], however, is that the Udachnaya xenoliths, like many other kimberlite-hosted peridotite suites worldwide, are extensively altered due to interaction with host magma and post-eruption alteration. This alteration causes particular dificulties for whole-rock studies including microstructures, modal estimates and chemical compositions. We report petrographic data and major and trace element compositions for whole-rocks and minerals of some 30 unusually fresh peridotite xenolith from the Udachnaya-East kimberlite. Our study has two goals. The first is to present and discuss trace element data on rocks and minerals from Udachnaya, whose composition remains little known. The other one is to explore how the availability of the fresh peridotites improves our knowledge of petrology and geochemistry of cratonic mantle in relation to published data on altered samples [1]. The xenoliths are spinel, garnet-spinel and garnet facies peridotites including garnet- and cpx-rich lherzolites, garnet and spinel harzburgites and dunites. Thermobarometric estimates for garnet bearing rocks yield T = 800-1350°C and P = 20-70 kbar, low-T spinel facies rocks may originate from shallower levels. Thus, the suite represents a lithospheric profile from the sub-Moho mantle down to ~210 km. The deeper peridotites commonly have porphyroclastic microstructures with mainly neoblast olivine, opx porphyroclasts and cpx and garnet with broadly variable morphologies whereas rocks of shallow origin are commonly protogranular. Trace element compositions in bulk rocks appear to be affected by host magma contamination with enrichments in highly to moderately incompatible elements as well as in alkalis. Nevertheless, the kimberlite-related contamination cannot explain a combination of low Th and U and high Sr contents. The broad range of heavy REE appears to be controlled by the presence and the abundance of garnet and is also related to microstructures such that granular spinel harzburgites have lower HREE contents than "fertile" porphyroclastic garnet lherzolites. Trace elements in cpx and garnet have equilibrated patterns in porphyroclastic peridotites and complex sinusoidal shapes in granular peridotites. Bulk-rock major element compositions show important variations in Mg# (0.89 - 0.93), SiO2 (41.5 - 46.6%), Al2O3 (0.3 - 4%) and CaO (0.3 - 4%). As for compatible trace elements, the major element compositions appear to be related to microstructures. Calculated modal compositions show highly variable opx contents (4.5 - 24%), which are generally lower than in Kaapvaal peridotites but are similar to those from the North Atlantic craton [3]. Overall, modal compositions and the contents of low-mobility elements, are consistent with an origin by variable degrees of partial melting of fertile mantle [1-3]. The range in FeO contents (6-8.5%) may indicate either variable melting depths [2] or post-melting enrichments. Enrichments in SiO2 show some similarities to those in supra-subduction xenoliths [4]; enrichments in highly incompatible elements can be explained by metasomatism with possible involvement of subduction-related fluids. Strong correlations between chemical compositions and microstructures indicate the involvement of tectonic processes in melt percolation and metasomatism. We suggest that the cratonic lithosphere in Siberia was formed in three stages: (1) formation of proto-cratonic mantle by high-degree melting at variable depth, (2) accretion of the proto-craton domains in subduction-related settings, (3) metasomatism commonly accompanied by deformation. [1] Boyd et al (1997) Contrib. Mineral. Petrol. 128, 228-246. [2] Herzberg (2004) J. Petrol. 45, 2507-2530. [3] Wittig et al (2008) Lithos 71, 289-322. [4] Ionov (2009) J. Petrol. In press

Ecotoxicological characterization of hazardous wastes.

PubMed

Wilke, B-M; Riepert, F; Koch, Christine; Kühne, T

2008-06-01

In Europe hazardous wastes are classified by 14 criteria including ecotoxicity (H 14). Standardized methods originally developed for chemical and soil testing were adapted for the ecotoxicological characterization of wastes including leachate and solid phase tests. A consensus on which tests should be recommended as mandatory is still missing. Up to now, only a guidance on how to proceed with the preparation of waste materials has been standardized by CEN as EN 14735. In this study, tests including higher plants, earthworms, collembolans, microorganisms, duckweed and luminescent bacteria were selected to characterize the ecotoxicological potential of a boiler slag, a dried sewage sludge, a thin sludge and a waste petrol. In general, the instructions given in EN 14735 were suitable for all wastes used. The evaluation of the different test systems by determining the LC/EC(50) or NOEC-values revealed that the collembolan reproduction and the duckweed frond numbers were the most sensitive endpoints. For a final classification and ranking of wastes the Toxicity Classification System (TCS) using EC/LC(50) values seems to be appropriate.

Food waste volume and origin: Case studies in the Finnish food service sector.

PubMed

Silvennoinen, Kirsi; Heikkilä, Lotta; Katajajuuri, Juha-Matti; Reinikainen, Anu

2015-12-01

We carried out a project to map the volume and composition of food waste in the Finnish food service sector. The amount, type and origin of avoidable food waste were investigated in 51 food service outlets, including schools, day-care centres, workplace canteens, petrol stations, restaurants and diners. Food service outlet personnel kept diaries and weighed the food produced and wasted during a one-week or one-day period. For weighing and sorting, the food waste was divided into two categories: originally edible (OE) food waste was separated from originally inedible (OIE) waste, such as vegetable peelings, bones and coffee grounds. In addition, food waste (OE) was divided into three categories in accordance with its origins: kitchen waste, service waste and customer leftovers. According to the results, about 20% of all food handled and prepared in the sector was wasted. The findings also suggest that the main drivers of wasted food are buffet services and overproduction. Copyright © 2015 Elsevier Ltd. All rights reserved.

Rheological and mechanical properties of recycled polyethylene films contaminated by biopolymer.

PubMed

Gere, D; Czigany, T

2018-06-01

Nowadays, with the increasing amount of biopolymers used, it can be expected that biodegradable polymers (e.g. PLA, PBAT) may appear in the petrol-based polymer waste stream. However, their impact on the recycling processes is not known yet; moreover, the properties of the products made from contaminated polymer blends are not easily predictable. Therefore, our goal was to investigate the rheological and mechanical properties of synthetic and biopolymer compounds. We made different compounds from regranulates of mixed polyethylene film waste and original polylactic acid (PLA) by extruison, and injection molded specimens from the compounds. We investigated the rheological properties of the regranulates, and the mechanical properties of the samples. When PLA was added, the viscosity and specific volume of all the blends decreased, and mechanical properties (tensile strength, modulus, and impact strength) changed significantly. Young's modulus increased, while elongation at break and impact strength decreased with the increase of the weight fraction of PLA. Copyright © 2018 Elsevier Ltd. All rights reserved.

The use of copula functions for modeling the risk of investment in shares traded on the Warsaw Stock Exchange

NASA Astrophysics Data System (ADS)

Domino, Krzysztof; Błachowicz, Tomasz

2014-11-01

In our work copula functions and the Hurst exponent calculated using the local Detrended Fluctuation Analysis (DFA) were used to investigate the risk of investment made in shares traded on the Warsaw Stock Exchange. The combination of copula functions and the Hurst exponent calculated using local DFA is a new approach. For copula function analysis bivariate variables composed of shares prices of the PEKAO bank (a big bank with high capitalization) and other banks (PKOBP, BZ WBK, MBANK and HANDLOWY in decreasing capitalization order) and companies from other branches (KGHM-mining industry, PKNORLEN-petrol industry as well as ASSECO-software industry) were used. Hurst exponents were calculated for daily shares prices and used to predict high drops of those prices. It appeared to be a valuable indicator in the copula selection procedure, since Hurst exponent’s low values were pointing on heavily tailed copulas e.g. the Clayton one.

Sustainability and in situ monitoring in battery development

NASA Astrophysics Data System (ADS)

Grey, C. P.; Tarascon, J. M.

2017-01-01

The development of improved rechargeable batteries represents a major technological challenge for this new century, as batteries constitute the limiting components in the shift from petrol (gasoline) powered to electric vehicles, while also enabling the use of more renewable energy on the grid. To minimize the ecological implications associated with their wider use, we must integrate sustainability of battery materials into our research endeavours, choosing chemistries that have a minimum footprint in nature and that are more readily recycled or integrated into a full circular economy. Sustainability and cost concerns require that we greatly increase the battery lifetime and consider second lives for batteries. As part of this, we must monitor the state of health of batteries continuously during operation to minimize their degradation. It is thus important to push the frontiers of operando techniques to monitor increasingly complex processes. In this Review, we will describe key advances in both more sustainable chemistries and operando techniques, along with some of the remaining challenges and possible solutions, as we personally perceive them.

A 59-year sedimentary record of metal pollution in the sediment core from the Huaihe River, Huainan, Anhui, China.

PubMed

Wang, Jie; Liu, Guijian; Zhang, Jiamei; Liu, Houqi; Lam, Paul K S

2016-12-01

An approximately 59-year (1955-2014) sedimentary record of metal elements (Cu, Pb, Zn, Ni, Co, Mn, and Fe) in a sediment core, collected from the Huaihe River, Huainan City, Anhui Province, China, was reconstructed by using 210 Pb geochronology. Copper, Zn, Ni, Co, and Mn evaluated by enrichment factor (EF) indicated minor contamination due to water pollution accidents of the Huaihe River that occurred in 1990s and 2004. Lead presented the most severe pollution among the metals studied, especially during 1957-1974. The use of leaded petrol and atmospheric deposition of coal combustion flue gases could have contributed to Pb contamination. In spite of the general good quality (mean sediment pollution index (SPI) 35.69) of the sediment core evaluated by SPI based on the principal component analysis, worse sediment qualities in the upper section (<6 cm, 2004) were still observed, suggesting intensive human activities causing the increasing concentrations of metals in recent decades.

Atmospheric polycyclic aromatic hydrocarbons in the urban environment: Occurrence, toxicity and source apportionment.

PubMed

Mishra, Nitika; Ayoko, Godwin A; Morawska, Lidia

2016-01-01

Polycyclic Aromatic Hydrocarbons (PAHs) represent a major class of toxic pollutants because of their carcinogenic and mutagenic characteristics. People living in urban areas are regularly exposed to PAHs because of abundance of their emission sources. Within this context, this study aimed to: (i) identify and quantify the levels of ambient PAHs in an urban environment; (ii) evaluate their toxicity; and (iii) identify their sources as well as the contribution of specific sources to measured concentrations. Sixteen PAHs were identified and quantified in air samples collected from Brisbane. Principal Component Analysis - Absolute Principal Component Scores (PCA-APCS) was used in order to conduct source apportionment of the measured PAHs. Vehicular emissions, natural gas combustion, petrol emissions and evaporative/unburned fuel were the sources identified; contributing 56%, 21%, 15% and 8% of the total PAHs emissions, respectively, all of which need to be considered for any pollution control measures implemented in urban areas. Copyright © 2015 Elsevier Ltd. All rights reserved.

A baseline study on the concentration of trace elements in the surface sediments off Southwest coast of Tamil Nadu, India.

PubMed

Godson, Prince S; Magesh, N S; Peter, T Simon; Chandrasekar, N; Krishnakumar, S; Vincent, Salom Gnana Thanga

2018-01-01

Forty two surface sediment samples were collected in order to document baseline elemental concentration along the Southwest coast of Tamil Nadu, India. The elements detected were Manganese (Mn), Zinc (Zn), Iron (Fe), Copper (Cu), Nickel (Ni) and Lead (Pb). The concentration of Fe and Mn was primarily controlled by the riverine input. The source of Pb and Zn is attributed to leaded petrol and anti-biofouling paints. The calculated index (EF, Igeo and CF) suggests that the sediments of the study area are significantly enriched with all elements except Pb. The contamination factor showed the order of Mn>Zn>Fe>Cu>Ni>Pb. The sediment pollution index (SPI) revealed that the sediments belonged to low polluted to dangerous category. The correlation matrix and dendrogram showed that the elemental distribution was chiefly controlled by riverine input as well as anthropogenic activity in the coast. Copyright © 2017 Elsevier Ltd. All rights reserved.

A Verhulst model for microalgae Botryococcus sp. growth and nutrient removal in wastewater

NASA Astrophysics Data System (ADS)

Jamaian, Siti Suhana; Bakeri, Noorhadila Mohd; Sunar, Norshuhaila Mohamed; Gani, Paran

2017-08-01

Microalgae Botryococcus sp. is a colonial green alga found in lakes and reservoirs in Malaysia. Previous studies reported that the potential of Botryococcus sp. photosynthesis as a source of fuel. The Botryococcus sp. contains hydrocarbon up to 75% of dry weight, which can be converted into petrol, diesel or turbine fuel or other liquid or gaseous hydrocarbons. Recently, an experimental study was conducted on phycoremediation technology for wastewater using Botryococcus sp. The phycoremediation technology is useful to remove the excess of nutrients such as nitrogen, phosphorus and also have the ability to remove various pollutants from wastewater. This research implements the Verhulst model to estimate the nutrient removal by microalgae Botryococcus sp. from the wastewater. This model has been validated with the experiments of microalgae Botryococcus sp. grown in domestic and palm oil wastewater. The results suggested that microalgae Botryococcus sp. could be cultured in domestic and palm oil wastewater while nutrients are reduced from these wastewaters.

Sustainability and in situ monitoring in battery development.

PubMed

Grey, C P; Tarascon, J M

2016-12-20

The development of improved rechargeable batteries represents a major technological challenge for this new century, as batteries constitute the limiting components in the shift from petrol (gasoline) powered to electric vehicles, while also enabling the use of more renewable energy on the grid. To minimize the ecological implications associated with their wider use, we must integrate sustainability of battery materials into our research endeavours, choosing chemistries that have a minimum footprint in nature and that are more readily recycled or integrated into a full circular economy. Sustainability and cost concerns require that we greatly increase the battery lifetime and consider second lives for batteries. As part of this, we must monitor the state of health of batteries continuously during operation to minimize their degradation. It is thus important to push the frontiers of operando techniques to monitor increasingly complex processes. In this Review, we will describe key advances in both more sustainable chemistries and operando techniques, along with some of the remaining challenges and possible solutions, as we personally perceive them.

Barium isotope geochemistry of subduction-zone magmas

NASA Astrophysics Data System (ADS)

Yu, H.; Nan, X.; Huang, J.; Wörner, G.; Huang, F.

2017-12-01

Subduction zones are crucial tectonic setting to study material exchange between crust and mantle, mantle partial melting with fluid addition, and formation of ore-deposits1-3. The geochemical characteristics of arc lavas from subduction zones are different from magmas erupted at mid-ocean ridges4, because there are addition of fluids/melts from subducted AOC and its overlying sediments into their source regions in the sub-arc mantle4. Ba is highly incompatible during mantle melting5, and it is enriched in crust (456 ppm)6 relative to the mantle (7.0 ppm)7. The subducted sediments are also enriched in Ba (776 ppm of GLOSS)8. Moreover, because Ba is fluid soluble during subduction, it has been used to track contributions of subduction-related fluids to arc magmas9 or recycled sediments to the mantle10-11. To study the Ba isotope fractionation behavior during subduction process, we analyzed well-characterized, chemically-diverse arc lavas from Central American, Kamchatka, Central-Eastern Aleutian, and Southern Lesser Antilles. The δ137/134Ba of Central American arc lavas range from -0.13 to 0.24‰, and have larger variation than the arc samples from other locations. Except one sample from Central-Eastern Aleutian arc with obviously heavy δ137/134Ba values (0.27‰), all other samples from Kamchatka, Central-Eastern Aleutian, Southern Lesser Antilles arcs are within the range of OIB. The δ137/134Ba is not correlated with the distance to trench, partial melting degrees (Mg#), or subducting slab-derived components. The samples enriched with heavy Ba isotopes have low Ba contents, indicating that Ba isotopes can be fractionated at the beginning of dehydration process with small amount of Ba releasing to the mantle wedge. With the dehydration degree increasing, more Ba of the subducted slab can be added to the source of arc lavas, likely homogenizing the Ba isotope signatures. 1. Rudnick, R., 1995 Nature; 2. Tatsumi, Y. & Kogiso, T., 2003; 3. Sun, W., et al., 2015 Ore Geol. Rev.; 4. Pearce, J., & Peate, D., 1995 Annu. Rev. Earth Planet. Sci.; 5. Pilet, S., et al., 2011 J. Petrol.; 6. Sun S. & McDonough, W., 1989; 7. Rudnick, R. & Gao, S., 2003 Treatise on geochem.; 8. Plank, T. & Langmuir, C., 1998, CG; 9. Hawkesworth, C. & Norry, M., 1983 Shiva Pub.; 10. Murphy, D., et al., 2002 J. Petrol.; 11. Kuritani, T., et al., 2011 Nat. Geosci.

Boron isotope systematics during magma-carbonate interaction: an experimental study from Merapi (Indonesia) and Vesuvius (Italy)

NASA Astrophysics Data System (ADS)

Deegan, F. M.; Jolis, E. M.; Troll, V. R.; Freda, C.; Whitehouse, M.

2011-12-01

Carbonate assimilation is increasingly recognized as an important process affecting the compositional evolution of magma and its inherent ability to erupt explosively due to release of carbonate-derived CO2 [e.g., 1, 2, 3]. In order to gain insights into this process, we performed short time-scale carbonate dissolution experiments in silicate melt using natural starting materials from Merapi and Vesuvius volcanoes at magmatic pressure and temperature [2, 4]. The experiments enable us to resolve in detail the timescales, textures and chemical features of carbonate assimilation. Three compositionally distinct glass domains have been defined: i) Ca-normal glass, similar in composition to the starting material; ii) Ca-rich, contaminated glass; and iii) a diffusional glass interface between the Ca-normal and Ca-rich glass, characterized by steady interchange between SiO2 and CaO. Here we present new boron isotope data for the experimental products obtained by SIMS. The glasses show distinct and systematic variation in their δ11B (%) values. The contaminated glasses generally show extremely negative δ11B values (down to -41 %) relative to both the uncontaminated experimental glass and fresh arc volcanics (-7 to +7 % [5]). Considering that carbonates have δ11B values of +9 to +26 [6], the data cannot be explained by simple mixing processes between the end-members alone. This implies that the δ11B of the original contaminant was drastically modified before being incorporated into the melt, which can be explained by B isotope fractionation during breakdown and degassing of the carbonate. Our data represents the first B isotope analyses of experimental products of carbonate assimilation. They provide novel and well constrained insights into the behavior of boron upon degassing of carbonate. This, in turn, has implications for both i) late stage contamination and volatile addition to hazardous volcanic systems located over carbonate basement (cf. [7]) and ii) studies of mass transfer in subduction zones, where B is frequently employed as a tracer of deep crustal recycling [8]. [1] Chadwick et al. (2007) J. Petrol. 48, 1793-1812. [2] Deegan et al. (2010) J. Petrol. 51, 1027-1051. [3] Freda et al. (2010) Bull. Volcanol. 73, 241-256. [4] Jolis et al. (2011) in prep. [5] Leeman & Sisson (1996) Rev. Min. 33, 645-707. [6] Ishikawa & Nakamura (1993) Earth Planet Sci. Lett. 117, 567-580. [7] Deegan et al. (2011) Geology Today 27, 63-64. [8] Rose et al. (2001) Science 293, 281-283.

The effect of water activity and oxygen fugacity on the phase relations and oxidation state of Fe in parental ferrobasaltic magma of Skaergaard

NASA Astrophysics Data System (ADS)

Botcharnikov, R.; Koepke, J.; Holtz, F.; McCammon, C.

2003-04-01

Phase relations and differentiation in the ferrobasaltic (FeO*=13wt%) system "SC1", an assumed parental liquid of the Skaergaard layered intrusion, have been investigated experimentally at dry conditions (1 atm) [1, 2]. However, the Skaergaard magma is believed to contain water. The present study investigates the role of water and fO2 on the phase relations and differentiation of the "SC1" ferrobasaltic system. The crystallization experiments have been performed in an internally heated pressure vessel equipped with a rapid quench facility and Shaw-membrane to determine the prevailing oxygen fugacity within the sample capsule [3]. To prevent the Fe-loss into the capsule material and ensure the desired conditions inside the capsule, the AuPd capsules were presaturated with iron and starting glasses were preequilibrated at the expected fO2 of the run. Water activity was varied by changing the H2O/CO2 ratio in the fluid phase. The first results of the experiments at P=200 MPa, T=1200-1000°C, various oxygen fugacities (logfO2=FMQ+4 to FMQ-1) and water activities (0 to 1) show that water influences not only the liquidus temperatures and temperature interval of mineral crystallization but also the sequence of crystallizing minerals; when compared with the dry system. Since water solubility strongly depends on pressure in the pressure range of 200-300 MPa, corresponding to the storage conditions of Skaergaard magma, the aH2O of hydrous magma may change significantly as a result of convection. Thus, convection has the potential to produce significant differences in stability and proportions of the prevailing minerals. This, in turn, may contribute to the formation of complex layering of the Skaergaard intrusion. The Moessbauer analysis of the quenched glasses shows that the Fe3+ / Sum Fe ratio of the silicate melt is a positive function of the water activity and has a linear dependence on water mole fraction in the system at 1200°C. The decrease of Fe3+ / Sum Fe ratio of the water-bearing melt with decreasing oxygen fugacity is more pronounced than that calculated for dry melts after [4]. [1] Toplis MJ &Carroll MR, J. Petrol., 36, 1137-1170, 1995. [2] Lattard D &Partsch GM, Eur. J. Mineral., 13, 467-478, 2001. [3] Berndt J et al., Am. Mineral., 87, 1717-1726, 2002. [4] Kress VC &Carmichael ISE, Contr.Min.Petrol., 108, 82-92, 1991.

Experimental and textural constraints on mafic enclave formation in volcanic rocks

USGS Publications Warehouse

Coombs, M.L.; Eichelberger, J.C.; Rutherford, M.J.

2002-01-01

We have used experiments and textural analysis to investigate the process of enclave formation during magma mixing at Southwest Trident volcano, Alaska. Andesite enclaves are present throughout the four dacite lava flows produced by the eruption, and resemble mafic enclaves commonly found in other volcanic rocks. Our experiments replicate the pressure-temperature-time path taken by enclave-forming andesite magma as it is engulfed in dacite during magma mixing. Pressure and temperature information for the andesite and dacite are from [Coombs et al., Contrib. Mineral. Petrol. 140 (2000) 99-118]. The andesite was annealed at 1000??C, and then cooled to 890??C at rates of 110??C h1, 10??C h1 and 2??C h1. Once cooled to 890??C, andesite was held at this lower temperature from times ranging from 1 to 40 h. The andesite that was cooled at the slower rates of 2??C h1 and 10??C h1 most resembles enclave groundmass texturally and compositionally. Based on simple thermal calculations, these rates are more consistent with cooling of the andesite groundmass below an andesite-dacite interface than with cooling of enclave-sized spheres. If enclaves do crystallize as spheres, post-crystallization disaggregation must occur. Calculations using the MELTS algorithm [Ghiorso and Sack, Contrib. Mineral. Petrol. 119 (1995) 197-212] show that for incoming andesite to become less dense than the dacite to become less dense ???34 volume % of its groundmass must crystallize to undergo~18 volume % vesiculation; these values are similar to those determined for Southwest Trident enclaves. Thus such crystallization may lead to 'flotation' of enclaves and be a viable mechanism for enclave formation and dispersal. The residual melt in the cooling experiments did not evolve to rhyolitic compositions such as seen in natural enclaves due to a lack of a decompression step in the experiments. Decompression experiments on Southwest Trident dacite suggest an average ascent rate for the eruption of ???2-3 MPa h1. An andesite experiment that was cooled and then decompressed at this rate contains melt that matches that of the natural enclaves. It is apparent that decompression (ascent)-induced crystallization occurs in enclaves, but not in the form of microlites as happens in the dacite host, due either to insufficient residence time at chamber temperatures or to the pre-existing microphenocrysts which act as sites for new growth. ?? 2002 Elsevier Science B.V. All rights reserved.

Termochemical Models For Slags and Silicate Melts, Review and Perspectives

NASA Astrophysics Data System (ADS)

Ottonello, G.

Thermochemical models devoted to the comprehension of reactive and mixing properties of silicate melts and slags may be roughly grouped into four main classes: 1) fictive chemical; 2) quasi chemical; 3) fictive structural; 4) polymeric. In the first class we may group the fictive regular mixture approach of Ghiorso and Carmichael [1,2]and its extensions [3-5]and the subregular model of Berman and Brown [6]. To the second class belong the modified quasi chemical approach of Pelton and coworkers [7,8] , and the Kapoor - Froberg cellular model and its extensions [9-11]. The third class has much to share with the second one (and indeed the cellular model could be ascribed to this class as well). To this class belong the "central surround model" of Sastri and Lahiri [12] , the associated solution models of Bjorkman [13], Hastie and coworkers [14]and Goel and coworkers [15], the two sublattice model of Hillert and coworkers [16]and the polynomial expansions of Hoch and Arpshofen [17] . The fourth class encompasses the models of Masson[18-20] , Toop-Samis [21,22]and its extensions [23-25] . The phylosophy beyond each one of the four classes is basically different. Benefits and drawbacks are present in any of them, and applications are often limited to simple systems (or to sufficiently complex systems, in the case of arbitrary deconvolutions of type 1) and to limited P-T ranges. The crucial aspects of the various models will be outlined to some extent. It will be shown that, often, model conflictuality is only appartent and that, in some cases, model failure is unperceived by acritical utilizers. New perspectives in the future research devoted to the comprehension of melt reactivity in compositionally complex systems, with special enphasis on the solubility of gaseous components and unmixing, will be finally discussed. References: [1] Ghiorso M.S. and Carmichael I.S.E. (1980) Contrib. Mineral. Petrol., 71, 323-342. [2] Ghiorso M.S., Carmichael I.S.E., Rivers M.L. and Sack R.O. (1983) Contrib. Mineral. Petrol., 84, 107-145. [3] Papale P. (1997) Contrib. Mineral. Petrol., 126, 237-251. [4] Papale P. (1999) Amer. Mineral., 84, 477-492. [5] Nuccio P.M. and Paonita A. (2999) Earth Planet. Sci. Letters., 183, 499-512. [6] Berman R.G. and Brown T.H. (1984) Geochim. Cosmochim. Acta, 48, 661-678. [7] Lin P.L. and Pelton A.D. (1979) Metall. Trans. B., 10B, 667-675. [8] Pelton A.D. and Blander M. (1986) Metall. Trans. B., 17B, 805-15. [9] Kapoor M.L., Mehrotre G.M. and Frohberg M.G. (1975) Proc. Aust. Inst. Mining Metall., 254, 11. [10] Kapoor M.L., Frohberg G.M. (1971) Proc. Symp. "Chemical Metallurgy of Iron and Steel" Sheffield. [11] Taylor J.R. and Dinsdale A.T. (1990] CALPHAD, 14, 71-88. [12] Sastri P. and Lahiri A.K. (1986) Metall. Trans. B., 17B, 105-110. [13] Bjorkman B. (1985) CALPHAD, 9, 271-282. [14] Hastie J.W., Horton W.S., Plante E.R. and Bonnell D.W. (1982) High Temp. High Press., 14, 669-679. [15] Goel R.P., Kellogg H.H. and Larrain J.M. (1980) Metall. Trans. B., 11B, 107-117. [16] Hillert M., Sundman B. and Wang X. (1990) Metall. Trans. B., 21B, 303-12. [17] Hoch M. and Arpshofen I. (1984) Zeits. fur Metallkde., 75, 23-29. [18] Masson C.R. (1965) Proc. Roy. Soc. London, A287, 201-221. [19] Masson C.R. (1968) J. Amer. Ceram. Soc., 51, 134-143. [20] Masson C.R. (1972) Jour. Iron Steel Inst., 210, 89-96. [21] Toop G.W. and Samis C.S. (1962) Can. Met. Quart., 1, 129-52. [22] Toop G.W. and Samis C.S. (1962) Trans. AIME, 224, 878-87. [23] Ottonello G., Moretti R., Marini L. and Vetuschi Zuccolini M. (2000) Chem. Geol., 174, 157-179. [24] Ottonello G. (2001) J. Non-Cryst. Solids, 282, 72-85. [25] Moretti R. and Ottonello G. (2002) , Metall. Trans. (submitted).

Laboratory scale bioremediation of diesel hydrocarbon in soil by indigenous bacterial consortium.

PubMed

Sharma, Anjana; Rehman, Meenal Budholia

2009-09-01

In vitro experiment was performed by taking petrol pump soils and diesel in flasks with the micronutrients and macronutrients supplements. Cemented bioreactors having sterilized soil and diesel was used for in vivo analysis of diesel hydrocarbon degradation. There were two sets of experiments, first having three bioreactors (1) inoculated by KI. pneumoniae subsp. aerogenes with soil and diesel; (2) with addition of NH4NO3; and (3) served as control. In second set, one bioreactor was inoculated by bacterial consortium containing Moraxella saccharolytica, Alteromonas putrefaciens, KI. pneumoniae subsp. aerogenes and Pseudomonas fragi along with soil and diesel. The remaining two bioreactors (having NH4NO3 and control) were similar to the first set. The experiments were incubated for 30 days. Ability of bacterial inoculum to degrade diesel was analyzed through GC-MS. Smaller chain compounds were obtained after experimental period of 30 days. Rate of diesel degradation was better with the present bacterial consortium than individual bacteria. Present bacterial consortium can be a better choice for faster and complete remediation of contaminated hydrocarbon soils.

Environmental hazards of automobile mechanics in Ibadan, Nigeria.

PubMed

Omokhodion, F O

1999-01-01

A cross sectional survey was conducted among automobile mechanics and technicians in Ibadan to determine the socio-demographic characteristics and environmental hazards of these workers. Three hundred workers were interviewed. All respondents were males aged between 13 and 72 years of age. Educational attainment was poor, with only 20% of respondents having completed secondary education. Sanitation facilities were inadequate. Forty percent of workshops provided facilities for refuse disposal. Of the 33 workshops visited, only 1 provided toilet facilities. Most workers used facilities in neighbouring residential premises. Only three workshops (9%) had designated eating areas. Occupational exposure to petrol was common to all trades. Other occupational exposures were to petrochemicals such as engine oil and brake oil. Protective clothing was not used by the majority of workers. Only 25 (8%) respondents were wearing overalls at the time of our visit. This findings illustrate the typical work conditions of workers in small scale industries. There is a need for health education programmes about occupational and non-occupational diseases. This and other health promotion activities can be organized through the unions.

Production of Alkaline Protease by Solvent-Tolerant Alkaliphilic Bacillus circulans MTCC 7942 Isolated from Hydrocarbon Contaminated Habitat: Process Parameters Optimization

PubMed Central

Patil, Ulhas; Chaudhari, Ambalal

2013-01-01

In the present investigation, a newly isolated organic solvent-tolerant and alkaliphilic bacterial strain was reported from a hydrocarbon (gasoline and diesel) contaminated soil collected from the petrol station, Shirpur (India). The strain was identified as Bacillus circulans MTCC 7942, based on phenotype, biochemical, and phylogenetic analysis of 16S rRNA gene sequence. The capability of Bacillus circulans to secrete an extracellular, thermostable, alkaline protease and grow in the presence of organic solvents was explored. Bacillus circulans produced maximum alkaline protease (412 U/mL) in optimized medium (g/L): soybean meal, 15; starch, 10; KH2PO4, 1; MgSO4·7H2O, 0.05; CaCl2, 1; Na2CO3, 8; pH 10.0 at 37°C and 100 rpm. The competence of strain to grow in various organic solvents—n-octane, dodecane, n-decane, N,N-dimethylformamide, n-hexane, and dimethyl sulfoxide, establishes its potential as solvent-stable protease source for the possible applications in nonaqueous reactions and fine chemical synthesis. PMID:25937965

Experimental Analysis of Exhaust Manifold with Ceramic Coating for Reduction of Heat Dissipation

NASA Astrophysics Data System (ADS)

Saravanan, J.; Valarmathi, T. N.; Nathc, Rajdeep; Kumar, Prasanth

2017-05-01

Exhaust manifold plays an important role in the exhaust system, the manifold delivers the waste toxic gases to a safe distance and it is used to reduce the sound pollution and air pollution. Exhaust manifold suffers with lot of thermal stress, due to this blow holes occurs in the surface of the exhaust manifold and also more noise is developed. The waste toxic gases from the multiple cylinders are collected into a single pipe by the exhaust manifold. The waste toxic gases can damage the material of the manifold. In this study, to prevent the damage zirconia powder has been coated in the inner surface and alumina (60%) combined with titania (40%) has been used for coating the outer surface of the exhaust manifold. After coating experiments have been performed using a multiple-cylinder four stroke stationary petrol engine. The test results of hardness, emission, corrosion and temperature of the coated and uncoated manifolds have been compared. The result shows that the performance is improved and also emission is reduced in the coated exhaust manifold.

The Use of Electrical Resistivity Method to Mapping The Migration of Heavy Metals by Electrokinetic

NASA Astrophysics Data System (ADS)

Azhar, A. T. S.; Ayuni, S. A.; Ezree, A. M.; Nizam, Z. M.; Aziman, M.; Hazreek, Z. A. M.; Norshuhaila, M. S.; Zaidi, E.

2017-08-01

The presence of heavy metals contamination in soil environment highly needs innovative remediation. Basically, this contamination was resulted from ex-mining sites, motor workshop, petrol station, landfill and industrial sites. Therefore, soil treatment is very important due to metal ions are characterized as non-biodegradable material that may be harmful to ecological system, food chain, human health and groundwater sources. There are various techniques that have been proposed to eliminate the heavy metal contamination from the soil such as bioremediation, phytoremediation, electrokinetic remediation, solidification and stabilization. The selection of treatment needs to fulfill some criteria such as cost-effective, easy to apply, green approach and high remediation efficiency. Electrokinetic remediation technique (EKR) offers those solutions in certain area where other methods are impractical. While, electrical resistivity method offers an alternative geophysical technique for soil subsurface profiling to mapping the heavy metals migration by the influece of electrical gradient. Consequently, this paper presents an overview of the use of EKR to treat contaminated soil by using ERM method to verify their effectiveness to remove heavy metals.

Computational Fluid Dynamics Analysis of High Injection Pressure Blended Biodiesel

NASA Astrophysics Data System (ADS)

Khalid, Amir; Jaat, Norrizam; Faisal Hushim, Mohd; Manshoor, Bukhari; Zaman, Izzuddin; Sapit, Azwan; Razali, Azahari

2017-08-01

Biodiesel have great potential for substitution with petrol fuel for the purpose of achieving clean energy production and emission reduction. Among the methods that can control the combustion properties, controlling of the fuel injection conditions is one of the successful methods. The purpose of this study is to investigate the effect of high injection pressure of biodiesel blends on spray characteristics using Computational Fluid Dynamics (CFD). Injection pressure was observed at 220 MPa, 250 MPa and 280 MPa. The ambient temperature was kept held at 1050 K and ambient pressure 8 MPa in order to simulate the effect of boost pressure or turbo charger during combustion process. Computational Fluid Dynamics were used to investigate the spray characteristics of biodiesel blends such as spray penetration length, spray angle and mixture formation of fuel-air mixing. The results shows that increases of injection pressure, wider spray angle is produced by biodiesel blends and diesel fuel. The injection pressure strongly affects the mixture formation, characteristics of fuel spray, longer spray penetration length thus promotes the fuel and air mixing.

Telecommunications equipment power supply in the Arctic by means of solar panels

NASA Astrophysics Data System (ADS)

Terekhin, Vladimir; Lagunov, Alexey

2016-09-01

Development of the Arctic region is one of the priorities in the Russian Federation. Amongst other things, a reliable telecommunications infrastructure in the Arctic is required. Petrol and diesel generators are traditionally employed but their use has considerable environmental impact. Solar panels can be used as an alternative power source. The electricity generated will be sufficient to supply small-sized telecommunications equipment with total the power of over 80 watts. An installation consisting of the solar modules, a charge controller, batteries, an inverter and load was designed. Tests were conducted at Cape Desire of the Novaya Zemlya (island). The solar panels provided in excess of 80 W from 7 a.m. to 11 p.m. The batteries charge during this time was sufficient to provide the power supply for the communication equipment during the night, from 11 p.m. to 7 a.m. The maximum value of 638 W of the power generation was observed at 3 p.m. The minimum value of 46 W was at 4 a.m. The solar modules thus can be used during the polar day to power the telecommunications equipment.

Transboundary atmospheric lead pollution.

PubMed

Erel, Yigal; Axelrod, Tamar; Veron, Alain; Mahrer, Yitzak; Katsafados, Petros; Dayan, Uri

2002-08-01

A high-temporal resolution collection technique was applied to refine aerosol sampling in Jerusalem, Israel. Using stable lead isotopes, lead concentrations, synoptic data, and atmospheric modeling, we demonstrate that lead detected in the atmosphere of Jerusalem is not only anthropogenic lead of local origin but also lead emitted in other countries. Fifty-seven percent of the collected samples contained a nontrivial fraction of foreign atmospheric lead and had 206Pb/207Pb values which deviated from the local petrol-lead value (206Pb/207Pb = 1.113) by more than two standard deviations (0.016). Foreign 206Pb/207Pb values were recorded in Jerusalem on several occasions. The synoptic conditions on these dates and reported values of the isotopic composition of lead emitted in various countries around Israel suggest that the foreign lead was transported to Jerusalem from Egypt, Turkey, and East Europe. The average concentration of foreign atmospheric lead in Jerusalem was 23 +/- 17 ng/m3, similar to the average concentration of local atmospheric lead, 21 +/- 18 ng/ m3. Hence, the load of foreign atmospheric lead is similar to the load of local atmospheric lead in Jerusalem.

Antioxidant, pro-oxidant and cytotoxic properties of parsley.

PubMed

Dorman, H J Damien; Lantto, Tiina A; Raasmaja, Atso; Hiltunen, Raimo

2011-06-01

Parsley (Petroselinum crispum) leaves were macerated with a mixture of methanol: water: acetic acid to produce a crude extract which was then defatted with (40°-60°) petrol. Antioxidant activity of the extract was evaluated using a battery of in vitro assays, viz., iron(iii) reduction, iron(ii) chelation and free radical scavenging assays. Evaluation of the pro-oxidant activity of the extract was based upon its effects upon DNA fragmentation and protein carbonylation. Cytotoxicity and apoptotic effects of the extract were determined in non-cancerous CV1-P fibroblast and cancerous A375 melanoma cells using MTT and LDH tests and caspase 3-like activity assay. The highest concentration, 2.0 mg ml(-1), decreased the viability of both cell lines, however, the cancerous melanoma cells were slightly susceptible to the effects. The observed cytotoxicity was not due to the caspase 3 activity. In conclusion, the toxicity might be explained by the pro-oxidative activity of components within the extract against proteins and/or DNA but it is not related to caspase 3-dependent apoptosis within cells.

Occupational exposures and cancer of the colon and rectum.

PubMed

Gerhardsson de Verdier, M; Plato, N; Steineck, G; Peters, J M

1992-01-01

The associations between occupational risks and colorectal cancer were examined in a Swedish population-based, case-referent study. The study was performed in Stockholm in 1986-1988 and included 569 cases and 512 referents. Relative risks (RRs) with 95% confidence intervals were calculated for different occupations/chemicals. Elevated risks of colon cancer were found among male petrol station/automobile repair workers (RR = 2.3, 0.8-6.6) and among males exposed to asbestos (RR = 1.8, 0.9-3.6), while elevated risks of rectal cancer were found among males exposed to soot (RR = 2.2, 1.1-4.3), asbestos (RR = 2.2, 1.0-4.7), cutting fluids/oils (RR = 2.1, 1.1-4.0), and combustion gases from coal/coke/wood (RR = 1.9, 1.0-3.7). However, due to a high correlation between the above-mentioned variables and the few exposed subjects, it is difficult to separate their effects properly. These analyses were adjusted for age. Further adjustments for diet, body mass, and physical activity had little or no influence on the results.

Preliminary assessment of Malaysian micro-algae strains for the production of bio jet fuel

NASA Astrophysics Data System (ADS)

Chen, J. T.; Mustafa, E. M.; Vello, V.; Lim, P.; Nik Sulaiman, N. M.; Majid, N. Abdul; Phang, S.; Tahir, P. Md.; Liew, K.

2016-10-01

Malaysia is the main hub in South-East Asia and has one of the highest air traffic movements in the region. Being rich in biodiversity, Malaysia has long been touted as country rich in biodiversity and therefore, attracts great interests as a place to setup bio-refineries and produce bio-fuels such as biodiesel, bio-petrol, green diesel, and bio-jet fuel Kerosene Jet A-1. Micro-algae is poised to alleviate certain disadvantages seen in first generation and second generation feedstock. In this study, the objective is to seek out potential micro-algae species in Malaysia to determine which are suitable to be used as the feedstock to enable bio-jet fuel production in Malaysia. From 79 samples collected over 30 sites throughout Malaysia, six species were isolated and compared for their biomass productivity and lipid content. Their lipid contents were then used to derived the require amount of micro-algae biomass to yield 1 kg of certifiable jet fuel via the HEFA process, and to meet a scenario where Malaysia implements a 2% alternative (bio-) jet fuel requirement.

A Viscoplastic Stress Relaxation Model for Predicting Variations of the Least Principal Stress With Depth in Unconventional Reservoirs

NASA Astrophysics Data System (ADS)

Zoback, M. D.; Xu, S.; Rassouli, F.; Ma, X.

2016-12-01

In this paper we extend the viscoplastic stress relaxation model of Sone and Zoback (Jour. Petrol. Sci. and Eng., 2014) for predicting variations of least principal stress with stress and its impact on the vertical propagation of hydraulic fractures. Viscoplastic stress relaxation in clay-rich (or diagenetically immature) sedimentary rocks makes the stress field more isotropic. In normal faulting and strike-slip faulting environments, this causes the least principal stress to increase making such formations likely barriers to vertical hydraulic fracture growth. In order to predict the magnitude of viscoplastic stress relaxation in different unconventional formations, we generalize a constitutive law developed from a wide range of creep experiments in our lab over the past several years and apply it to areas of stacked pay in Oklahoma and Texas. Using frac gradients were measured from minifrac and DFIT (Diagnostic Fracture Injection Test) experiments. The viscoplastic model does a good job of explaining vertical hydraulic fracture propagation, as indicated by the distribution of microseismic events recorded during stimulation.

Lipase-inorganic hybrid nanoflower constructed through biomimetic mineralization: A new support for biodiesel synthesis.

PubMed

Jiang, Wei; Wang, Xinghuo; Yang, Jiebing; Han, Haobo; Li, Quanshun; Tang, Jun

2018-03-15

We reported a facile, economic and green method based on biomimetic mineralization to acquire lipase-inorganic hybrid nanoflower, which was then employed as a biocatalyst for biodiesel production. In the hybrid nanoflower, enzyme molecules and Cu 2+ ions were utilized as the organic and inorganic components, respectively. The morphology of nanoflower and the distribution and loading of proteins were systematically characterized by scanning electron microscopy, confocal laser scanning microscopy and ultraviolet-visible spectroscopy, which indicated the successful encapsulation of lipase in the hybrid nanoflower. Using the hydrolysis of p-nitrophenyl caprylate as a model, lipase-inorganic hybrid nanoflower was observed to possess favorable catalytic activity and stability in the ester hydrolysis. Further, the hybrid nanoflower was used as a catalyst for biodiesel production, in which it could convert sunflower oil to biodiesel with 96.5% conversion and remain 72.5% conversion after being used for 5 cycles. Thus, the lipase-inorganic hybrid nanoflower is potential to be used as an economically viable biocatalyst for the production of biofuel as the future petrol-fuel replacement. Copyright © 2017 Elsevier Inc. All rights reserved.

Multiple regression analysis in modelling of carbon dioxide emissions by energy consumption use in Malaysia

NASA Astrophysics Data System (ADS)

Keat, Sim Chong; Chun, Beh Boon; San, Lim Hwee; Jafri, Mohd Zubir Mat

2015-04-01

Climate change due to carbon dioxide (CO2) emissions is one of the most complex challenges threatening our planet. This issue considered as a great and international concern that primary attributed from different fossil fuels. In this paper, regression model is used for analyzing the causal relationship among CO2 emissions based on the energy consumption in Malaysia using time series data for the period of 1980-2010. The equations were developed using regression model based on the eight major sources that contribute to the CO2 emissions such as non energy, Liquefied Petroleum Gas (LPG), diesel, kerosene, refinery gas, Aviation Turbine Fuel (ATF) and Aviation Gasoline (AV Gas), fuel oil and motor petrol. The related data partly used for predict the regression model (1980-2000) and partly used for validate the regression model (2001-2010). The results of the prediction model with the measured data showed a high correlation coefficient (R2=0.9544), indicating the model's accuracy and efficiency. These results are accurate and can be used in early warning of the population to comply with air quality standards.

Injection system used into SI engines for complete combustion and reduction of exhaust emissions in the case of alcohol and petrol alcohol mixtures feed

NASA Astrophysics Data System (ADS)

Ispas, N.; Cofaru, C.; Aleonte, M.

2017-10-01

Internal combustion engines still play a major role in today transportation but increasing the fuel efficiency and decreasing chemical emissions remain a great goal of the researchers. Direct injection and air assisted injection system can improve combustion and can reduce the concentration of the exhaust gas pollutes. Advanced air-to-fuel and combustion air-to-fuel injection system for mixtures, derivatives and alcohol gasoline blends represent a major asset in reducing pollutant emissions and controlling combustion processes in spark-ignition engines. The use of these biofuel and biofuel blending systems for gasoline results in better control of spark ignition engine processes, making combustion as complete as possible, as well as lower levels of concentrations of pollutants in exhaust gases. The main purpose of this paper was to provide most suitable tools for ensure the proven increase in the efficiency of spark ignition engines, making them more environmentally friendly. The conclusions of the paper allow to highlight the paths leading to a better use of alcohols (biofuels) in internal combustion engines of modern transport units.

Lead and cadmium content in human milk from the Northern Adriatic area of Croatia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Frkovic, A.; Kras, M.; Alebic-Juretic, A.

Though occupational exposure to toxic metals (lead, cadmium) is well documented, harmful effects of environmental exposure to lower levels of these two metals is still under investigation. Most toxic metals are emitted by human activities and the atmosphere is the main transport route for these elements. According to some authors, 332 358 t of lead and 7570 t of cadmium were emitted in the atmosphere from anthropogenic sources in 1983. The principle source of lead is traffic, e.g. leaded petrol, still widely used in Croatia, as well as coal combustion, iron and steal production. Volcanic activity, zinc production and wastemore » incineration are the main sources of cadmium. Recent study indicates that traffic could also be the main source of cadmium found along busy streets. Chronic lead exposure at low levels is associated with adverse health effects especially in fetus and young children. This study examines lead and cadmium levels in breast milk from nursing women living in the Northern Adriatic area of Croatia. 15 refs., 2 tabs.« less

Design and development of the Macpherson Proton Preve Magneto rheological damper with PID controller

NASA Astrophysics Data System (ADS)

Amiruddin, I. M.; Pauziah, M.; Aminudin, A.; Unuh, M. H.

2017-10-01

Since the creation of the first petrol-fuelled vehicle by Karl Benz in the late nineteenth century, car industry has grown considerably to meet the industrial demands. Luxurious looks and agreeable rides are the primary needs of drivers. The Magneto-rheological damper balanced their damping trademark progressively by applying the damping coefficient depending on the control system. In this research, the control calculations are assessed by utilizing the MR damper. The capacity and reliably of the target force for the damper speed is investigated from control algorithm. This is imperative to defeat the damper limitation. In this study, the simulation results of the semi-dynamic MR damper with the PID controller shows better performance in sprung mass acceleration, unsprung mass acceleration and suspension dislodging with permitting over the top tyre acceleration. The altered model of the MR damper is specially designed for Proton Preve specifications and semi-active PID control. The procedure for the advancement incorporates the numerical model to graphically recreate and break down the dynamic framework by utilizing Matlab.

Use of porous materials to remove oil contaminants from water.

PubMed

Gołub, Adam; Piekutin, Janina

2018-06-15

The purpose of the research was to remove petroleum substances from water using porous materials. Birch bark, cork, glass wool and polyurethane foam were used for the study. The model solution was distilled water enriched with a mixture of petrol and diesel fuel in a volume ratio of 1:3. The model water used had 3 different concentrations of oil substances. The research included petroleum substances expressed as mineral oil index and aliphatic hydrocarbons, n-alkanes (from C7H16 to C38H78). The process of oil substances removal was carried out applying two methods: static and dynamic. Based on the research, it was found that materials the most effective in lowering the index of mineral oil and C7H16-C38H78 n-alkane concentrations were both birch bark and glass wool, both static and dynamic, while cork and polyurethane foam were less effective. In addition, concentration of C7H16-C38H78 n-alkanes was lowered in each measurement series to a greater extent than the mineral oil index. Copyright © 2018 Elsevier B.V. All rights reserved.

Influence of fuel composition on polycyclic aromatic hydrocarbon emissions from a fleet of in-service passenger cars

NASA Astrophysics Data System (ADS)

Lim, McKenzie C. H.; Ayoko, Godwin A.; Morawska, Lidia.; Ristovski, Zoran D.; Jayaratne, E. Rohan

The composition of exhaust emissions from eight in-service passenger cars powered by liquefied petroleum gas (LPG) and unleaded petrol (ULP) were measured on a chassis dynamometer at two driving speeds (60 and 80 km h -1) with the aims of evaluating their polycyclic aromatic hydrocarbon (PAH) contents and investigating the effects of the type of fuel on vehicle performance, ambient air quality and associated health risks. Naphthalene, fluorene, phenanthrene, anthracene, pyrene, chrysene, benzo(a)anthracene and benzo(b)fluoranthene were the most prominent PAHs emitted by both ULP and LPG powered cars. The total emission factors of PAHs from LPG cars were generally lower than (but statistically comparable with) those of ULP cars. Similarly, the total BAP eq of the PAHs emitted by LPG cars were lower than those from ULP cars. Multi-criteria decision making (MCDM) methods showed that cars powered by LPG fuel performed better than those powered by ULP fuel in term of PAH levels. The implications of these observations on the advantages and disadvantages of using ULP and LPG fuels are discussed.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stechel, Ellen Beth; Ambrosini, Andrea; Coker, Eric Nicholas

The Sunshine to Petrol effort at Sandia aims to convert carbon dioxide and water to precursors for liquid hydrocarbon fuels using concentrated solar power. Significant advances have been made in the field of solar thermochemical CO{sub 2}-splitting technologies utilizing yttria-stabilized zirconia (YSZ)-supported ferrite composites. Conceptually, such materials work via the basic redox reactions: Fe{sub 3}O{sub 4} {yields} 3FeO + 0.5O{sub 2} (Thermal reduction, >1350 C) and 3FeO + CO{sub 2} {yields} Fe{sub 3}O{sub 4} + CO (CO{sub 2}-splitting oxidation, <1200 C). There has been limited fundamental characterization of the ferrite-based materials at the high temperatures and conditions present in thesemore » cycles. A systematic study of these composites is underway in an effort to begin to elucidate microstructure, structure-property relationships, and the role of the support on redox behavior under high-temperature reducing and oxidizing environments. In this paper the synthesis, structural characterization (including scanning electron microscopy and room temperature and in-situ x-ray diffraction), and thermogravimetric analysis of YSZ-supported ferrites will be reported.« less

The P-T conditions of garnet inclusion formation in diamond: thermal expansion of synthetic end-member pyrope

NASA Astrophysics Data System (ADS)

Milani, Sula; Mazzucchelli, Matteo; Nestola, Fabrizio; Alvaro, Matteo; Angel, Ross J.; Geiger, Charles A.; Domeneghetti, Chiara

2013-04-01

Pyrope, Mg3Al2Si3O12, due to the abundance of garnet in Earths's upper mantle, has been studied many times. A number of different investigations have measured its physical and thermodynamic properties at high temperature or pressure and, even more recently, under simultaneous high P-T conditions (e.g. Zou et al., 2012). This abstract reports thermal expansion results on pyrope, as part of a much wider project on the determination of the physical properties of garnet, in order to obtain geobarometric information on the formation conditions of its inclusion in diamond. Our experimental approach is based on the elastic method (e.g. Izraeli et al., 1999; Howell et al., 2010; Nestola et al., 2011; Howell et al., 2012), which takes into account the thermoelastic properties of both diamond and any tiny solid phase inclusion within it. The method requires accurate and precise knowledge of thermal expansion and compressibility behavior in order to calculate precisely the pressure and temperature formation conditions of the diamond-inclusion pair. Thus, in order to do this, we measured the thermal expansion of an end-member synthetic single crystal of pyrope up to 1100 K at 52 different temperatures. This was done by measuring the ao unit-cell edge with high precision and accuracy under heating and cooling conditions. This allows excellent experimental reproducibility, which is also checked by monitoring any diffraction peak broadening over the entire range of temperatures. Fitting the temperature-volume data to the thermal expansion equation of Berman (1988), we obtained a room temperature volume-thermal expansion coefficient equal to 2.72(2)×10-5K-1. Using the same pyrope crystal, in situ high-pressure measurements are now in progress in order to determine its isothermal bulk modulus. The use of our results, along with the dK/dT data of Zou et al ( 2012), we plan to calculate the pressure of formation of diamonds containing pyrope-rich garnet inclusions. References Berman, R.G. (1988) J. Petrol., 29, 445-522. Zou Y., Irifune T., Greaux S., Whitaker M.L., Ohfuji H., Shinmei T., Higo Y., Baosheng L. (2012) Abstract n° MR43C-2333, AGU FALL MEETING 2012. Howell, D., Wood, I.G., Dobson, D.P., Jones, A.P., Nasdala, L., Harris, J.W. (2010) Contrib. Mineral. Petrol., 160, 705-717. Howell, D., Wood, I.G., Nestola, F., Nimis, P., Nasdala, L. (2012) Eur. J. Mineral., ,. Izraeli, E.S., Harris, J.W., Navon, O. (1999) Earth Planet Sci. Lett., 173, 351-360. Nestola, F., Nimis, P., Ziberna, L., Longo, M., Marzoli, A., Harris, J.W., Manghnani, M.H., Fedortchouk, Y. (2011) Earth Plan. Sc. Lett., 305, 249-255.

Mediterranean salt giants beyond the evaporite model: The Sicily perspective

NASA Astrophysics Data System (ADS)

Carmelo Manuella, Fabio; Scribano, Vittorio; Carbone, Serafina; Hovland, Martin; Johnsen, Hans-Konrad; Rueslåtten, Håkon

2017-04-01

Mediterranean salt giants, occurring both in sub-seafloor and in onshore settings (the "Gessoso Solfifera Group"), are traditionally explained by repeated cycles of desiccation and replenishment of the entire basin. However, such hypotheses are strongly biased by mass balance calculations and geodynamic considerations. In addition, any hypothesis without full desiccation, still based on the evaporite model, should consider that seawater brines start to precipitate halite when 2/3 of the seawater has evaporated, and hence the level of the basin cannot be the same as the adjacent ocean. On the other hand, hydrothermal venting of hot saline brines onto the seafloor can precipitate salt in a deep marine basin if a layer of heavy brine exists along the seafloor. This process, likely related to sub-surface boiling or supercritical out-salting (Hovland et al., 2006), is consistent with geological evidence in the Red Sea "Deeps" (Hovland et al., 2015). Although supercritical out-salting and phase separation can sufficiently explain the formation of several marine salt deposits, even in deep marine settings, the Mediterranean salt giant formations can also be explained by the serpentinization model (Scribano et al., 2016). Serpentinization of abyssal peridotites does not involve seawater salts, and large quantities of saline brines accumulate in pores and fractures of the sub-seafloor serpentinites. If these rocks undergo thermal dehydration, for example, due to igneous intrusions, brines and salt slurries can migrate upwards as hydrothermal plumes, eventually venting at the seafloor, giving rise to giant salt deposits over time. These hydrothermal processes can take place in a temporal sequence, as it occurred in the "Caltanissetta Basin" (Sicily). There, salt accumulation associated with serpentinization started during Triassic times (and even earlier), and venting of heavy brines onto the seafloor eventually occurred in the Messinian via the hydrothermal plume mechanism (Scribano et al, 2016). This innovative model arises from the study of xenoliths in the Hyblean diatremes (southeastern Sicily), suggesting that a widely serpentinized Tethyan basement lies beneath the entire Sicily island and its offshore areas (Scribano et al., 2006; Manuella et al., 2015), according to geophysical, geological and petrological aspects. In conclusion, our viewpoint represents a plausible explanation for the origin of giant salt deposits in the Mediterranean area and elsewhere, albeit this hypothesis should be constrained by further studies. Hovland et al. (2006), Mar. Petrol. Geol., 23, 855-869. Hovland et al. (2015), In: Rasul, N.M.A., and Stewart, I.C.F., eds., The Red Sea. Springer, 187-203. DOI: 10.1007/978-3-662-45201-1_11 Manuella et al. (2015), Int. J. Earth Sci., 104, 1317-1336. Scribano et al. (2006), Mineral. Petrol., 86, 63-88. Scribano et al. (2016), Int. J. Earth Sci., submitted.

Specifics of soil temperature under winter oilseed rape canopy

NASA Astrophysics Data System (ADS)

Krčmářová, Jana; Středa, Tomáš; Pokorný, Radovan

2014-09-01

The aim of this study was to evaluate the course of soil temperature under the winter oilseed rape canopy and to determine relationships between soil temperature, air temperature and partly soil moisture. In addition, the aim was to describe the dependence by means of regression equations usable for pests and pathogens prediction, crop development, and yields models. The measurement of soil and near the ground air temperatures was performed at the experimental field Žabiče (South Moravia, the Czech Republic). The course of temperature was determined under or in the winter oilseed rape canopy during spring growth season in the course of four years (2010 - 2012 and 2014). In all years, the standard varieties (Petrol, Sherpa) were grown, in 2014 the semi-dwarf variety PX104 was added. Automatic soil sensors were positioned at three depths (0.05, 0.10 and 0.20 m) under soil surface, air temperature sensors in 0.05 m above soil surfaces. The course of soil temperature differs significantly between standard (Sherpa and Petrol) and semi-dwarf (PX104) varieties. Results of the cross correlation analysis showed, that the best interrelationships between air and soil temperature were achieved in 2 hours delay for the soil temperature in 0.05 m, 4 hour delay for 0.10 m and 7 hour delay for 0.20 m for standard varieties. For semi-dwarf variety, this delay reached 6 hour for the soil temperature in 0.05 m, 7 hour delay for 0.10 m and 11 hour for 0.20 m. After the time correction, the determination coefficient (R2) reached values from 0.67 to 0.95 for 0.05 m, 0.50 to 0.84 for 0.10 m in variety Sherpa during all experimental years. For variety PX104 this coefficient reached values from 0.51 to 0.72 in 0.05 m depth and from 0.39 to 0.67 in 0.10 m depth in the year 2014. The determination coefficient in the 0.20 m depth was lower for both varieties; its values were from 0.15 to 0.65 in variety Sherpa. In variety PX104 the values of R2 from 0.23 to 0.57 were determined. When using multiple regressions with quadratic spacing (modelling of hourly soil temperature based on the hourly near surface air temperature and hourly soil moisture in the 0.10-0.40 m profile), the difference between the measured and modelled soil temperatures in the depth of 0.05 m was -3.92 to 3.99°C. The regression equation paired with alternative agrometeorological instruments enables relatively accurate modelling of soil temperatures (R2 = 0.95).

Lithospheric heterogeneity beneath the EARS interpreted from major and trace element analyses of mafic rocks

NASA Astrophysics Data System (ADS)

Hamblock, J.; Anthony, E.; Omenda, P.; Chesley, J.

2003-04-01

We report chemical analyses for tholeiites from the axial region of the EARS and tholeiites and basanites from the Chyulu Hills Volcanic Province (CHVP), located on the SE flank of the Kenya Rift. The purpose of the study is to: i) explore contrasts in lithospheric composition from the axial region, where seismic velocities imply high temperatures and presence of melt at shallow depths, to the flanks, where geophysical studies indicate thick lithosphere and a zone of partial melt centered under the CHVP (Ritter and Kaspar, 1997, Tectonophysics 278, 149-169). ii) investigate plume components and plume-lithosphere interactions in the different settings. This study complements the characterization of lithosphere along the axis of the Rift by MacDonald et al. (2001, J. Petrol. 42, 877-900) and the study of temporal evolution of the CHVP by Späth et al. (2001, J. Petrol. 42, 765-787). Basanites within the CHVP are similar to OIB in their trace-element patterns, but with a pronounced negative K-anomaly. Späth et al. attribute this anomaly to melting of a lithospheric mantle source containing amphibole. They postulate, based on radiogenic isotopes (Sr, Pb, Nd), recent metasomatism due to interaction of the lithosphere with the EARS plume. High La/Yb suggests a source within the garnet-peridotite field. Tholeiites from the CHVP are distinct in trace-element chemistry from basanites, with flatter multi-element patterns and generally lower elemental concentrations. The CHVP tholeiites have La/Yb indicative of a spinel peridotite source. The role of crustal contamination for tholeiites remains open; however, substantial evidence exists for lithospheric heterogeneity beneath the CHVP. Axial lavas show similar elemental behavior as the CHVP: basanites have negative K-anomalies (MacDonald et al., 2001), whereas tholeiites do not. Tholeiites have flat multi-element patterns with low overall concentrations, similar to those from the CHVP, with one significant difference tholeiites from the axial region have variable and high concentrations of Ba, K, and Ta, which may represent a more pervasive plume component. The Mg-number of lavas from the axial region are significantly lower than lavas in the CHVP, suggesting greater degrees of crystal fractionation and potentially longer residence times in crustal magma chambers. In conclusion, evidence exists in both areas for lithospheric mantle heterogeneity, but in both areas the elemental signature is highly correlated to silica saturation. For a given group of lavas of similar silica saturation, the elemental patterns are similar from the axis to the flank. This observation implies that there are not strong lateral contrasts in lithospheric composition across the EARS.

Pressure variations in the Monte Rosa nappe, Western Alps

NASA Astrophysics Data System (ADS)

Luisier, Cindy; Vaughan-Hammon, Joshua; Baumgartner, Lukas; Schmalholz, Stefan

2017-04-01

The Monte Rosa nappe is part of the Penninic nappe stack of the Western Alps. It represents the southern-most European continental basement involved in the alpine orogeny. It consists of a pre-Variscan basement complex, made of mostly metapelites and paragneisses, which were intruded by a Permian-age granitic body (Pawlig, 2001). The nappe is heterogeneously deformed, with localized high strain domains separating low strain domains. The metamorphic record is tightly linked to deformation. Different thermodynamic data bases and approaches were used in the past to estimate the peak alpine metamorphic conditions. They range from 1.2 to 2.7 GPa and 490 to 650˚C, based on metagranite, metapelite, metamafic and whiteschist assemblages. The peak alpine metamorphic assemblage of zoisite, phengite and albite symplectites pseudomorphing magmatic plagioclase is preserved only in the less deformed portions of the nappe. Phengite, garnet and titanite coronas surrounding biotite, quartz and igneous K-feldspar make up the rest of the rock. The metagranite locally grades into 10 to 50 meters whiteschist bodies, consisting of talc-chloritoid-kyanite-phengite-quartz, which can contain carbonate and garnet. Their chemistry is interpreted as a metasomatic product of the late magmatic hydrothermal alteration of the granite, whereas their mineralogy results from the alpine high pressure metamorphism (Pawlig and Baumgartner, 2001; Luisier et al., 2015). We performed a phase petrology and textural study to consistently estimate peak alpine metamorphic conditions in the granite and the related whiteschists. Textural observations were used to select the best-preserved high-pressure metagranite samples. Inherited magmatic feldspar textures indicate that jadeite was never formed in these granites, confirmed independently by Si in phengite barometer (1.2 to 1.5 GPa). Note that the granite contains the phengite buffer assemblage of Massonne and Schreyer (1987). Thermodynamic calculations using internally consistent thermodynamic database on whiteschists result in a minimum P of 2.2 GPa at T of 550 to 570˚C and a water activity close to 1, unlike previous water activities proposed (Le Bayon et al., 2006). Peak alpine pressures and temperatures calculated for the metagranite and associated whiteschists hence result in significant different pressure estimates, corroborating previous results from the literature. The possible explanations for such pressure variations are i) slight underestimation of the metagranite peak pressure, due to water-undersaturation conditions, however a pressure as high as 2 GPa is unlikely, or ii) heterogeneous stress conditions, due to rheologically contrasting lithologies, consisting of weak whiteschist inclusions within strong, undeformed metagranites. References Le Bayon et al., 2006: Contrib. Mineral. Petrol. 151, 395-412 Luisier et al., 2015: GSA conference abstract Massonne and Schreyer, 1987: Contrib. Mineral. Petrol. 96, 212-224 Pawlig, S. 2001: PhD thesis, University of Mainz (Germany) Pawlig and Baumgartner, 2001: SMPM 81,329-346

The Chemical Structure of the Hawaiian Mantle Plume

NASA Astrophysics Data System (ADS)

Ren, Z.; Hirano, N.; Hirata, T.; Takahashi, E.; Ingle, S.

2004-12-01

Numerous geochemical studies of Hawaiian basaltic lavas have shown that the Hawaiian mantle plume is isotopically heterogeneous. However, the distribution and scale of these heterogeneities remain unknown. This is essentially due to the complex interactions created by melting a heterogeneous source, subsequent aggregation of the melts on their way to the surface, and mixing that takes place in shallow magma chambers prior to eruption. In sum, the measured compositions of bulk lavas may represent only _eaverage_f compositions that do not fully reflect the complexity of either the mantle source heterogeneity and/or chemical structure. Melt inclusions, or samples of the local magma frozen in olivine phenocrysts during their formation, are better at recording the complex magmatic history than are the bulk samples. Here, we report major and trace element compositions of olivine-hosted melt inclusions from submarine Haleakala lavas that were collected by 2001-2002 JAMSTEC cruises measured by EPMA and LA-ICP-MS after homogenization at 1250° C, QFM for 20min. Melt inclusions from the submarine Hana Ridge (Haleakala volcano) show large ranges in CaO/Al2O3 (0.92-1.50), TiO2/Na2O (0.79-1.60) and Sr/Nb (14.56-36.60), Zr/Nb (6.48-16.95), ranging from Kilauea-like to Mauna Loa-like compositions within separately-sampled lavas as well as in a single host lava sample. Bulk rocks geochemistry shows that major element composition and trace element ratios such as Zr/Nb, Sr/Nb (Ren et al., 2004a, in press, J. Petrol.) together with Pb, Nd and Sr isotopic ratios (Ren et al., 2004b, submitted to J. Petrol.) of Haleakala shield volcano also display systematic compositional variation changing from a Kilauea-like in the submarine Hana Ridge (main shield stage) to Kilauea-Mauna Loa-like in the subaerial Honomanu stage (late shield stage, data from Chen and Frey, 1991). Some of the compositional variations in melt inclusions in single rocks are wider range than over-all variation observed in bulk rocks. It is important that both Kilauea-like and Mauna Loa-like compositions co-exist in melt inclusions in single submarine Hana Ridge rocks which are identified as Kilauea-like based on bulk geochemistry. These observations are inconsistent with the current interpretation that magma compositions are controlled by concentric zonation of the Hawaiian mantle plume (e.g. Kea component and Loa component), manifested as the Kea trend and the Loa trend volcanoes (e.g. Hauri, 1996; Lassiter et al., 1996). Our new data from olivine-hosted melt inclusions imply that the chemical structure of the Hawaiian mantle plume is significantly more complicated than previously modeled and the length-scale of chemical heterogeneity must be remarkably smaller than estimated based on bulk rock geochemistry.

Alcohol consumption and its related harms in The Netherlands since 1960: relationships with planned and unplanned factors.

PubMed

Knibbe, Ronald A; Derickx, Mieke; Allamani, Allaman; Massini, Giulia

2014-10-01

to establish which unplanned (social developments) and planned (alcohol policy measures) factors are related to per capita consumption and alcohol-related harms in the Netherlands. linear regression was used to establish which of the planned and unplanned factors were most strongly connected with alcohol consumption and harms. Artificial Neural Analysis (ANN) was used to inspect the interconnections between all variables. mothers age at birth was most strongly associated with increase in consumption. The ban on selling alcoholic beverages at petrol station was associated with a decrease in consumption. The linear regression of harms did not show any relation between alcohol policy measures and harms. The ANN-analyses indicate a very high interconnectedness between all variables allowing no causal inferences. Exceptions are the relation between price of beer and wine and the consumption of these beverages and the relation between a decrease in transport mortality and the increased use of breathalyzers tests and a restriction of paracommercial selling. unplanned factors are most strongly associated with per capita consumption and harms. ANN-analysis indicates that price of alcoholic beverages, breath testing, and restriction of sales may have had some influence. The study's limitations are noted.

Synthesis, characterization and potential utility of doped ceramics based catalysts

NASA Astrophysics Data System (ADS)

Sharma, Ritika; Yadav, Deepshikha; Singh, G. P.; Vyas, G.; Bhojak, N.

2018-05-01

Excessive utilization of petrol, diesel and other fossil fuels, continuous increase in their prices, and the big problem of carbon dioxide mission have encouraged scientists and technologist to find either new sources of energy or to develop technologies for the sustainable utilization of fuel. Biofuels are the only energy technologies that can resolve the problem of carbon dioxide emission in the atmosphere as well as reduce the amount of fossil fuel burned. Bio ethanol and biodiesel are the most common types of biofuel which are being used at present. Biodiesel has become more interesting for all the researchers in present scenario. Various feedstock viz. edible, nonedible oils, waste cooking oil, animal fat, algae etc, are using for the production of biodiesel worldwide according to their availability. Selection of efficient heterogeneous catalysts for biodiesel preparation still needs more attention of researchers. The present investigation deals with determination of synthesis, characterization and applications of doped ceramic based materials in different medium. Two of doped ceramic based catalysts which has been potentially used for the production of biodiesel. The Engine performance of biodiesel samples, made from industrial waste oils and ceramic based catalyst, have also been investigated and found up to satisfactory levels.

Benchmarking of Decision-Support Tools Used for Tiered Sustainable Remediation Appraisal.

PubMed

Smith, Jonathan W N; Kerrison, Gavin

2013-01-01

Sustainable remediation comprises soil and groundwater risk-management actions that are selected, designed, and operated to maximize net environmental, social, and economic benefit (while assuring protection of human health and safety). This paper describes a benchmarking exercise to comparatively assess potential differences in environmental management decision making resulting from application of different sustainability appraisal tools ranging from simple (qualitative) to more quantitative (multi-criteria and fully monetized cost-benefit analysis), as outlined in the SuRF-UK framework. The appraisal tools were used to rank remedial options for risk management of a subsurface petroleum release that occurred at a petrol filling station in central England. The remediation options were benchmarked using a consistent set of soil and groundwater data for each tier of sustainability appraisal. The ranking of remedial options was very similar in all three tiers, and an environmental management decision to select the most sustainable options at tier 1 would have been the same decision at tiers 2 and 3. The exercise showed that, for relatively simple remediation projects, a simple sustainability appraisal led to the same remediation option selection as more complex appraisal, and can be used to reliably inform environmental management decisions on other relatively simple land contamination projects.

Installation-Restoration Program. Phase 2. Confirmation/quantification. Stage 1. Problem confirmation study: Otis Air National Guard Base, Massachusetts, Air National Guard Support Center, Andrews Air Force Base, Maryland. Final technical report, November 1983-July 1985

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kraybill, R.L.; Smart, G.R.; Bopp, F.

1985-09-04

A Problem Confirmation Study was performed at seven sites on Otis Air National Guard Base: the Current and Former Training Areas, the Base Landfill, the Nondestructive Inspection Laboratory, the Fuel Test Dump Site, the Railyard Fuel Pumping Station, and the Petrol Fuel Storage Area. The field investigation was conducted in two stages, in November 1983 through January 1984, and in October through December 1984. Resampling was performed at selected locations in April and July 1985. A total of 11 monitor wells were installed and sampled and test-pit investigations were conducted at six sites. In addition, the contents of a sumpmore » tank, and two header pipes for fuel-transmission lines were sampled. Analytes included TOC, TOX, cyanide, phenols, Safe Drinking Water metals, pesticides and herbicides, and in the second round, priority-pollutant volatile organic compounds and a GC fingerprint scan for fuel products. On the basis of the field-work findings, it is concluded that, to date, water-quality impacts on ground water from past activities have been minimal.« less

The shape and dynamics of the generation of the splash forms in single-phase systems after drop hitting

NASA Astrophysics Data System (ADS)

Sochan, Agata; Beczek, Michał; Mazur, Rafał; RyŻak, Magdalena; Bieganowski, Andrzej

2018-02-01

The splash phenomenon is being increasingly explored with the use of modern measurement tools, including the high-speed cameras. Recording images at a rate of several thousand frames per second facilitates parameterization and description of the dynamics of splash phases. This paper describes the impact of a single drop of a liquid falling on the surface of the same liquid. Three single-phase liquid systems, i.e., water, petrol, and diesel fuel, were examined. The falling drops were characterized by different kinetic energy values depending on the height of the fall, which ranged from 0.1 to 7.0 m. Four forms, i.e., waves, crowns, semi-closed domes, and domes, were distinguished depending on the drop energy. The analysis of the recorded images facilitated determination of the static and dynamic parameters of each form, e.g., the maximum height of each splash form, the width of the splash form at its maximum height, and the rate of growth of the splash form. We, Re, Fr, and K numbers were determined for all analyzed liquid systems. On the basis of the obtained values of dimensionless numbers, the areas of occurrence of characteristic splash forms were separated.

Evaluation of purchase intention of customers in two wheeler automobile segment: AHP and TOPSIS

NASA Astrophysics Data System (ADS)

Sri Yogi, Kottala

2018-03-01

Winning heart of customers is preeminent main design of any business organization in global business environment. This paper explored customer’s priorities while purchasing a two wheeler automobile segment using Analytical Hierarchy Process (AHP) and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) as a multi criteria decision making tools to accomplish the research objectives. Study has been done to analyze different criteria to be considered during purchasing of two wheeler automobiles among respondents using structured questionnaire based on SAATY scale. Based on our previous work on empirical & fuzzy logic approach to product quality and purchase intention of customers in two wheeler- operational, performance, economic, brand value and maintenance aspects are considered as decision criteria of customers while purchasing a two wheeler. The study suggests high pick up during overtaking, petrol saving, reasonable spare parts price, unique in design and identity and easy to change gear as main criterion in purchasing process. We also found some leading two wheeler automobiles models available in Indian market using some objective function criterion in choosing some important characteristics like price, cylinder capacity, brake horse power and weight during purchasing process of two wheeler automobile in Indian market based on respondents perception.

Health Risk Assessment of Ambient Air Concentrations of Benzene, Toluene and Xylene (BTX) in Service Station Environments

PubMed Central

Edokpolo, Benjamin; Yu, Qiming Jimmy; Connell, Des

2014-01-01

A comprehensive evaluation of the adverse health effects of human exposures to BTX from service station emissions was carried out using BTX exposure data from the scientific literature. The data was grouped into different scenarios based on activity, location and occupation and plotted as Cumulative Probability Distributions (CPD) plots. Health risk was evaluated for each scenario using the Hazard Quotient (HQ) at 50% (CEXP50) and 95% (CEXP95) exposure levels. HQ50 and HQ95 > 1 were obtained with benzene in the scenario for service station attendants and mechanics repairing petrol dispensing pumps indicating a possible health risk. The risk was minimized for service stations using vapour recovery systems which greatly reduced the benzene exposure levels. HQ50 and HQ95 < 1 were obtained for all other scenarios with benzene suggesting minimal risk for most of the exposed population. However, HQ50 and HQ95 < 1 was also found with toluene and xylene for all scenarios, suggesting minimal health risk. The lifetime excess Cancer Risk (CR) and Overall Risk Probability for cancer on exposure to benzene was calculated for all Scenarios and this was higher amongst service station attendants than any other scenario. PMID:24945191

Environmental lead exposure: a public health problem of global dimensions.

PubMed Central

Tong, S.; von Schirnding, Y. E.; Prapamontol, T.

2000-01-01

Lead is the most abundant of the heavy metals in the Earth's crust. It has been used since prehistoric times, and has become widely distributed and mobilized in the environment. Exposure to and uptake of this non-essential element have consequently increased. Both occupational and environmental exposures to lead remain a serious problem in many developing and industrializing countries, as well as in some developed countries. In most developed countries, however, introduction of lead into the human environment has decreased in recent years, largely due to public health campaigns and a decline in its commercial usage, particularly in petrol. Acute lead poisoning has become rare in such countries, but chronic exposure to low levels of the metal is still a public health issue, especially among some minorities and socioeconomically disadvantaged groups. In developing countries, awareness of the public health impact of exposure to lead is growing but relatively few of these countries have introduced policies and regulations for significantly combating the problem. This article reviews the nature and importance of environmental exposure to lead in developing and developed countries, outlining past actions, and indicating requirements for future policy responses and interventions. PMID:11019456

A survey of air quality in Singapore

NASA Astrophysics Data System (ADS)

Lai, Y. K.; Tang, S. M.

1993-04-01

Ambient aerosol samples were collected near an industrial area in Singapore during the period of July 91 to January 92. The sampling site was a highway at a height of about 20 m. PIXE analysis of these samples was carried out using 1.8 MeV protons. Thirteen trace elements were observed, ranging from Si to Pb. Among these, Cl and S had the highest concentrations. The former was attributed to the sea-salt particles and the latter could be due to the presence of oil refineries in the vicinity. Pb was found to be below the detection limit of 30 ngm -3 in most of the samples analysed. This is likely due to the fact that unleaded petrol was used by many cars in Singapore and that the sampling point was quite a distance away from the ground level. The observed variations in concentration for most of the trace elements were well-correlated with traffic intensity and meteorological conditions. Time variation patterns on weekdays and during weekends were also observed. A higher level of pollutants was detected during the period when there were prolonged forest fires in the nearby islands in Indonesia.

Developmental neurotoxicity of industrial chemicals.

PubMed

Grandjean, P; Landrigan, P J

2006-12-16

Neurodevelopmental disorders such as autism, attention deficit disorder, mental retardation, and cerebral palsy are common, costly, and can cause lifelong disability. Their causes are mostly unknown. A few industrial chemicals (eg, lead, methylmercury, polychlorinated biphenyls [PCBs], arsenic, and toluene) are recognised causes of neurodevelopmental disorders and subclinical brain dysfunction. Exposure to these chemicals during early fetal development can cause brain injury at doses much lower than those affecting adult brain function. Recognition of these risks has led to evidence-based programmes of prevention, such as elimination of lead additives in petrol. Although these prevention campaigns are highly successful, most were initiated only after substantial delays. Another 200 chemicals are known to cause clinical neurotoxic effects in adults. Despite an absence of systematic testing, many additional chemicals have been shown to be neurotoxic in laboratory models. The toxic effects of such chemicals in the developing human brain are not known and they are not regulated to protect children. The two main impediments to prevention of neurodevelopmental deficits of chemical origin are the great gaps in testing chemicals for developmental neurotoxicity and the high level of proof required for regulation. New, precautionary approaches that recognise the unique vulnerability of the developing brain are needed for testing and control of chemicals.

Mesophilic anaerobic digestion: first option for waste treatment in tropical regions.

PubMed

Suryawanshi, P C; Chaudhari, A B; Kothari, R M

2010-12-01

Rural India derives its energy needs for cooking and heating through the use of fuel wood and for lighting and agricultural operations through kerosene and diesel. Use of fuel wood has aggravated the problem of de-forestation, while availability of kerosene and diesel cannot be guaranteed due to corrupt practices in the public distribution systems. In contrast, urban India derives its energy needs through LPG cylinders, petrol, and electricity. However, their cost and uncertainty rendered them beyond the reach of lower income population. This scenario is more or less true with many developing countries. To meet these objectives, biogas generation from biodegradable waste using anaerobic digestion (AD) appears to be a sustainable avenue as it could be used for (a) water and space heating of farmhouses, animal shelters, (b) generating steam for food processing plants, and (c) electricity generation, in addition to reducing the pollution/hazard potential of these wastes. Many of the underdeveloped and developing countries are in the temperate zone and thus mesophilic AD could provide a desired pathway to achieve a long delayed need of energy for comfortable living, farming, and industrial operations. Efforts made in this direction are reviewed in the present article.

Conventional, Hybrid, or Electric Vehicles: Which Technology for an Urban Distribution Centre?

PubMed Central

Lebeau, Philippe; De Cauwer, Cedric; Macharis, Cathy; Verbeke, Wouter; Coosemans, Thierry

2015-01-01

Freight transport has an important impact on urban welfare. It is estimated to be responsible for 25% of CO2 emissions and up to 50% of particles matters generated by the transport sector in cities. Facing that problem, the European Commission set the objective of reaching free CO2 city logistics by 2030 in major urban areas. In order to achieve this goal, electric vehicles could be an important part of the solution. However, this technology still faces a number of barriers, in particular high purchase costs and limited driving range. This paper explores the possible integration of electric vehicles in urban logistics operations. In order to answer this research question, the authors have developed a fleet size and mix vehicle routing problem with time windows for electric vehicles. In particular, an energy consumption model is integrated in order to consider variable range of electric vehicles. Based on generated instances, the authors analyse different sets of vehicles in terms of vehicle class (quadricycles, small vans, large vans, and trucks) and vehicle technology (petrol, hybrid, diesel, and electric vehicles). Results show that a fleet with different technologies has the opportunity of reducing costs of the last mile. PMID:26236769

Conventional, Hybrid, or Electric Vehicles: Which Technology for an Urban Distribution Centre?

PubMed

Lebeau, Philippe; De Cauwer, Cedric; Van Mierlo, Joeri; Macharis, Cathy; Verbeke, Wouter; Coosemans, Thierry

2015-01-01

Freight transport has an important impact on urban welfare. It is estimated to be responsible for 25% of CO2 emissions and up to 50% of particles matters generated by the transport sector in cities. Facing that problem, the European Commission set the objective of reaching free CO2 city logistics by 2030 in major urban areas. In order to achieve this goal, electric vehicles could be an important part of the solution. However, this technology still faces a number of barriers, in particular high purchase costs and limited driving range. This paper explores the possible integration of electric vehicles in urban logistics operations. In order to answer this research question, the authors have developed a fleet size and mix vehicle routing problem with time windows for electric vehicles. In particular, an energy consumption model is integrated in order to consider variable range of electric vehicles. Based on generated instances, the authors analyse different sets of vehicles in terms of vehicle class (quadricycles, small vans, large vans, and trucks) and vehicle technology (petrol, hybrid, diesel, and electric vehicles). Results show that a fleet with different technologies has the opportunity of reducing costs of the last mile.

Contamination history of lead and other trace metals reconstructed from an urban winter pond in the Eastern Mediterranean coast (Israel).

PubMed

Zohar, I; Bookman, R; Levin, N; de Stigter, H; Teutsch, N

2014-12-02

Pollution history of Pb and other trace metals was reconstructed for the first time for the Eastern Mediterranean, from a small urban winter pond (Dora, Netanya), located at the densely populated coastal plain of Israel. An integrated approach including geochemical, sedimentological, and historical analyses was employed to study sediments from the center of the pond. Profiles of metal concentrations (Pb, Zn, V, Ni, Cu, Cr, Co, Cd, and Hg) and Pb isotopic composition denote two main eras of pre- and post-19th century. The deeper sediment is characterized by low concentrations and relatively constant 206Pb/207Pb (around 1.20), similar to natural Pb sources, with slight indications of ancient anthropogenic activity. The upper sediment displays an upward increase in trace metal concentrations, with the highest enrichment factor for Pb (18.4). Lead fluxes and isotopic composition point to national/regional petrol-Pb emissions as the major contributor to Pb contamination, overwhelming other potential local and transboundary sources. Traffic-related metals are correlated with Pb, emphasizing the polluting inputs of traffic. The Hg profile, however, implies global pollution rather than local sources.

[Motor transport emission, ambient air quality, and the Moscow population's health].

PubMed

Ivanenko, A V; Volkova, I F; Kornienko, A P

2007-01-01

As of 2006, the city's motor transport fleet amounted to as many as 3 million units that annually consume about 5 million tons of petrol. The use rate of all kinds of vehicles has increased, resulting in the growth of the proportion of ambient air pollutants discharged by motor transport, which surpasses the increase of the absolute size of the fleet. The contribution of traveling sources to ambient air pollution is growing steadily and it has been recently about 90% (1 million tons). Implementation of measures and developed managerial decisions, and ecological programs, improvement of Moscow town-planning measures, and environment-improving measures against motor vehicles have contributed to a reduction in chemical and physical burdens on the population. The characteristics of the capital's ambient air pollution have been recently observed to become stable and improve. There is stabilization in morbidity due to respiratory diseases in all population groups. The prevalence of chronic respiratory diseases in children is on the decrease, the increase rate was 1.4% versus 33.5% in the preceding period. Assessment of carcinogenic risk showed that ambient air pollution and drinking water contamination had a negative impact on the Moscow population.

Key issues in controlling air pollutants in Dhaka, Bangladesh

NASA Astrophysics Data System (ADS)

Begum, Bilkis A.; Biswas, Swapan K.; Hopke, Philip K.

2011-12-01

Particulate matter (PM) sampling for both coarse and fine fractions was conducted in a semi-residential site (AECD) in Dhaka from February 2005 to December 2006. The samples were analyzed for mass, black carbon (BC), and elemental compositions. The resulting data set were analyzed for sources by Positive Matrix Factorization (EPA-PMF). From previous studies, it is found that, the air quality became worse in the dry winter period compared to the rainy season because of higher particulate matter concentration in the ambient air. Therefore, seasonal source contributions were determined from seasonally segregated data using EPA-PMF modeling so that further policy interventions can be undertaken to improve air quality. From the source apportionment results, it is observed that vehicular emissions and emission from brick kiln are the major contributors to air pollution in Dhaka especially in the dry seasons, while contribution from emissions from metal smelters increases during rainy seasons. The Government of Bangladesh is considering different interventions to reduce the emissions from those sources by adopting conversion of diesel/petrol vehicles to CNG, increasing traffic speed in the city and by introducing green technologies for brick production. However, in order to reduce the transboundary effect it is necessary to take action regionally.

Cholinesterase and Prolyl Oligopeptidase Inhibitory Activities of Alkaloids from Argemone platyceras (Papaveraceae).

PubMed

Siatka, Tomáš; Adamcová, Markéta; Opletal, Lubomír; Cahlíková, Lucie; Jun, Daniel; Hrabinová, Martina; Kuneš, Jiří; Chlebek, Jakub

2017-07-14

Alzheimer's disease is an age-related, neurodegenerative disorder, characterized by cognitive impairment and restrictions in activities of daily living. This disease is the most common form of dementia with complex multifactorial pathological mechanisms. Many therapeutic approaches have been proposed. Among them, inhibition of acetylcholinesterase, butyrylcholinesterase, and prolyl oligopeptidase can be beneficial targets in the treatment of Alzheimer's disease. Roots, along with aerial parts of Argemone platyceras , were extracted with ethanol and fractionated on an alumina column using light petrol, chloroform and ethanol. Subsequently, repeated preparative thin-layer chromatography led to the isolation of (+)-laudanosine, protopine, (-)-argemonine, allocryptopine, (-)-platycerine, (-)-munitagine, and (-)-norargemonine belonging to pavine, protopine and benzyltetrahydroisoquinoline structural types. Chemical structures of the isolated alkaloids were elucidated by optical rotation, spectroscopic and spectrometric analysis (NMR, MS), and comparison with literature data. (+)-Laudanosine was isolated from A. platyceras for the first time. Isolated compounds were tested for human blood acetylcholinesterase, human plasma butyrylcholinesterase and recombinant prolyl oligopeptidase inhibitory activity. The alkaloids inhibited the enzymes in a dose-dependent manner. The most active compound (-)-munitagine, a pavine alkaloid, inhibited both acetylcholinesterase and prolyl oligopeptidase with IC 50 values of 62.3 ± 5.8 µM and 277.0 ± 31.3 µM, respectively.

The short-term impact of economic uncertainty on motor vehicle collisions.

PubMed

Vandoros, Sotiris; Avendano, Mauricio; Kawachi, Ichiro

2018-06-01

Stress and anxiety lead to attention loss and sleep deprivation and may reduce driving performance, increasing the risk of motor vehicle collision. We used evidence from a natural experiment to examine whether daily changes in economic uncertainty, potentially leading to attention or sleep loss, are associated with collisions in Great Britain. Daily data from the economic policy uncertainty index, derived from analysis of daily UK newspapers, were linked to the daily number of motor vehicle collisions in Great Britain over the period 2005-2015, obtained from the Department for Transport. Exploiting daily variations in economic uncertainty, we used a GARCH approach to model daily rates of motor vehicle collisions as a function of economic uncertainty, controlling for month and day of the week, monthly unemployment rates and weekly unleaded petrol prices. A spike in the daily economic uncertainty index was associated with an immediate increase in the number of motor vehicle collisions. Results were robust to various sensitivity analyses. Overall, daily increases in economic uncertainty are associated with short-term spikes in motor vehicle collisions. Preventive and traffic control measures may need to increase during periods of economic uncertainty. Copyright © 2018 Elsevier Inc. All rights reserved.

A Continuous Liquid-Level Sensor for Fuel Tanks Based on Surface Plasmon Resonance

PubMed Central

Pozo, Antonio M.; Pérez-Ocón, Francisco; Rabaza, Ovidio

2016-01-01

A standard problem in large tanks at oil refineries and petrol stations is that water and fuel usually occupy the same tank. This is undesirable and causes problems such as corrosion in the tanks. Normally, the water level in tanks is unknown, with the problems that this entails. We propose herein a method based on surface plasmon resonance (SPR) to detect in real time the interfaces in a tank which can simultaneously contain water, gasoline (or diesel) and air. The plasmonic sensor is composed of a hemispherical glass prism, a magnesium fluoride layer, and a gold layer. We have optimized the structural parameters of the sensor from the theoretical modeling of the reflectance curve. The sensor detects water-fuel and fuel-air interfaces and measures the level of each liquid in real time. This sensor is recommended for inflammable liquids because inside the tank there are no electrical or electronic signals which could cause explosions. The sensor proposed has a sensitivity of between 1.2 and 3.5 RIU−1 and a resolution of between 5.7 × 10−4 and 16.5 × 10−4 RIU. PMID:27213388

History of initial fifty years of ARIES: A Major National Indian Facility for Optical Observations

NASA Astrophysics Data System (ADS)

Sanwal, Basant Ballabh; Pandey, Anil Kumar; Uddin, Wahab; Kumar, Brijesh; Joshi, Santosh

2018-04-01

The idea of starting an astronomical observatory in the state of Uttar Pradesh in India germinated through the initiative of a scholarly statesman Babu Sampurnanandji. His interest in astrology coupled with his academic bent of mind got him interested in modern astronomy. Being then Education Minister and later Chief Minister of Uttar Pradesh, he established an astronomical observatory at Varanasi on April 20, 1954. Later on it was shifted to Manora Peak, Nainital. Four reflectors were commissioned at Manora Peak. For solar research an H alpha petrol unit and a horizontal solar spectrograph was setup. A detailed project report for installation of a 4-m class optical telescope was prepared indigenously in late 1980, however, the project could not take off. With the generous support of the Department of Science and Technology, the institute established a 3.6-m new technology optical telescope and a 1.3-m wide field optical telescope at a new observing site called Devasthal. Now a 4-m liquid mirror telescope is also being installed at the same observing site. I present here a brief journey of the observatory beginning right from its birth in 1954 till now.

Surface Resistance of Jute Fibre/Polylactic Acid Biocomposite to Wet Heat

NASA Astrophysics Data System (ADS)

Zandvliet, Clio; Bandyopadhyay, N. R.; Ray, Dipa

2016-04-01

Jute fibre/polylactic acid (PLA) composite is of special interest because both resin and reinforcement come from renewable resources. Thus, it could be a more eco-friendly alternative to glass fibre composite [1] and to conventional wood-based panels made with phenol-formaldehyde resin which present many drawbacks for the workers and the environment [2]. Yet the water affinity of the natural fibres, the susceptibility of PLA towards hydrolysis and the low glass transition of the PLA raise a question about the surface resistance of such composites to wet heat in service condition for a furniture application [3]. In this work, the surface resistance of PLA/jute composite alone and with two different varnishes are investigated in regard to an interior application following the standard test method in accordance to BS EN 18721:2009: "Furniture: assessment of surface resistance to wet heat". It is compared to two common wood based panels, plywood and hardboard. After test, the composite material surface is found to be more affected than plywood and hardboard, but it becomes resistant to wet heat when a layer of biosourced varnish or petrol-based polyurethane varnish are applied on the surface.

A longitudinal study of externally visible cigarette advertising on retail storefronts in Massachusetts before and after the Master Settlement Agreement

PubMed Central

Celebucki, C; Diskin, K

2002-01-01

Methods: Observations were conducted on the number of cigarette advertisements visible from outside tobacco retail establishments in a paired convenience sample (n = 556) in Massachusetts before and after the MSA. Archival databases containing information on merchant compliance with age related sales laws during the time period were used to assess the relation of total cigarette advertising with sales to underage youth. Paired sample t tests assessed planned comparisons pre- to post-MSA; Spearman's ρ tested associations for dichotomous variables. Results: Significant post-ban increases were observed in the prevalence of exterior cigarette advertising on gas (petrol) stations and gas mini/marts (gasoline retailers) buildings, windows, and doors. Significant declines were observed on windows of liquor stores. Winston advertising declined overall, while advertisements of the "all other" brand category increased. Correlations between advertising and illegal sales, while modest, were significant. Conclusions: These pre- to post-MSA increases suggest the tobacco industry may be shifting expenditures selectively from billboard advertising to retailer exteriors more favoured by youth. Greater amount of cigarette advertising visible from outside over-the-counter tobacco retailers is associated with greater cigarette sales to minors. PMID:12034982

Effect of fO2 on phase relationship in basaltic andesites during magmatic differentiation: Control of fO2 and sulphur speciation in piston cylinder experiments.

NASA Astrophysics Data System (ADS)

Matjuschkin, Vladimir; Tattitch, Brian; Blundy, Jonathan D.; Skora, Susanne

2014-05-01

Within the mantle wedge above subduction zones, oxidation reaction take place by interaction of reduced mantle rocks with more oxidized, hydrous fluids, which can cause a local drop of the solidus, resulting in partial melting (2,6,7). The resultant melts are more oxidized that their ocean floor counterparts, which has implications for their subsequent differentiation paths, the speciation of multivalent elements and the solubility and transport of chemical compounds in magmatic systems (1,4,5). We present a series of sulphur-doped high-pressure experiments conducted to investigate the effect of oxygen fugacity on phase relationships and the behaviour of sulphur in silicate melts. Natural aphyric andesite (FM37) erupted from Laguna del Maule volcano, Chile (3) was selected as a starting composition. Experiments were carried out at 5kbar, 950-1150° C and variable oxygen fugacity conditions. New experiments buffered at Co-CoO and Ni-NiO buffer conditions have been performed using a new "MTB capsule design" developed in order to accurately control fO2 by means of a double capsule containing metal-oxide buffers and a pyrex sleeve to minimise H2 diffusion. This new design constrains oxygen fugacity to within ±0.1-0.2logfO2 units of the target value. Before conducting these experiments, the assemblage was tested multiple times at 10kbar, 1000° C over 24-48 hours and demonstrated consistent, accurate fO2 control. Analyses of the preliminary experimental run products, from a related Chilean basaltic andesite starting composition, demonstrate a clear effect of fO2 on phase relationships and the proportion of melt generated during experiments. Under oxidized conditions, as temperature decreased from 1150° C to 1050° C, the amount of melt decreased from 100% to ~80%, due to the formation of orthopyroxene, anhydrite and plagioclase. In contrast, in reduced runs the system remains nearly liquid (~5% crystals) down to 950° C due to the change in sulphur speciation and onset of orthopyroxene precipitation at much lower temperatures. The change in temperature from 1150 to 950° C resulted in a drop in S content from ~2500ppm to ~1000ppm in the melt for oxidized experiments, whereas S slightly increased from ~3000 to ~3500ppm in the reduced experiments. Quantitative control over fO2 will allow for more precise determination of phase relations and control of sulphur specification, offering a possibility of detailed reconstruction of metals enrichment in silicate melts. Cited references: [1] Botcharnikov et al. (2011) Nature 4:217-230, [2] Foley (2011) J Petrol 52:1363-1391, [3] Frey et al. (1984) CMP 88:133-149, [4] Jenner et al. (2010) J Petrol 51:2445-2464, [5] Jugo et al. (2010) GCA 74:5926-5938, [6] Rohrbach et al. (2007) Nature 449:456-458, [7] Taylor and Green (1988) Nature 332:349-352

Investigating Alpine fissure rutilated quartz to constrain timing and conditions of post-metamorphic hydrothermal fluid flow

NASA Astrophysics Data System (ADS)

Shulaker, D. Z.; Schmitt, A. K.; Zack, T.; Bindeman, I. N.

2013-12-01

Rutilated quartz, aka Venus' hair, is finely-acicular rutile intergrown with host quartz generated by fluid-mediated co-crystallization. It is commonly found in hydrothermal veins, including the renown cleft mineral locations of the Swiss Alps. Previous studies of Alpine cleft mineralizations used rare hydrothermal monazite [1] and titanite [2] to constrain vein formation to ~13.5-15.2 Ma, postdating peak metamorphism by ~2-4 Ma. Temperature (T) estimates of 150-450°C are based on fluid inclusions and bulk quartz-mineral oxygen isotope exchange equilibria, and formation pressures (P) are 0.5-2.5 kbar (for a geothermal gradient of 30°C/km) [2]. The potential of rutilated quartz as a thermochronometer, however, has not been harnessed previously. Here, we present the first results of age and P-T determinations for rutilated quartz from six locations in the Swiss Alps (San Gottardo; Feldbach, Binntal; Pi Aul, Vals; Faido, Leventina; Elm, Steinbach; Binntal). Samples were cut and mounted in epoxy discs to expose rutile (0.03 to 1 mm in diameter) and its host quartz which was also imaged in cathodoluminescence (CL). CL images for half of the samples' host quartz exhibited strong sector zoning, while others reveal only weak CL zonation. Isotopic and trace element analyses were carried out by SIMS using a CAMECA ims1270 for U-Pb, O-isotopes, and Ti-in-quartz, and a LA-ICP-MS system (213 nm New Wave laser coupled to an Agilent 7500a) for Zr-in-rutile. U-Pb rutile ages average 15.5×2.0 Ma (2σ). T estimates are 352-575°C (rutile-quartz oxygen isotopes in touching domains), 470-530°C (Zr-in-rutile assuming P = 0.5 and equilibrium with host-rock zircon), and 251-391°C (Ti-in-quartz at assumed P = 0.5 kbar and aTiO2 = 1). CL zones are isotopically unzoned. Rutile-quartz oxygen isotopes are pressure insensitive, whereas Zr-in-rutile and Ti-in-quartz are minimum temperatures. These results demonstrate that rutilated quartz can constrain timing and conditions of post-metamorphic hydrothermal fluid flow and mineralization. Discrepancies in thermometers are attributed to differences between experimental calibrations of isotopic and trace element thermometers, and the conditions of post-metamorphic hydrothermal fluid flow. Only rutile-quartz oxygen isotope exchange [3] has been calibrated close to natural T conditions for rutilated quartz (500°C). This may help to extend the applicability of the Ti-in-quartz and Zr-in-rutile to T below experimental calibrations (>600°C; [4] and >700°C; [5], resp.). [1] Janots et al., 2012, Chem. Geol., 326-327, 61-71 [2] Mullis, 1996, Schweiz. Mineral. Petrogr. Mitt., 76, 159-164 [3] Matthews, 1994, J. Met. Geol., 12, 211-219 [4] Thomas et al., 2010, Contrib. Mineral. Petrol., 160, 743-759 [5] Ferry and Watson, 2007, Contrib. Mineral. Petrol., 154, 429-437

Detrital geochronology of unroofing magmatic complexes

NASA Astrophysics Data System (ADS)

Malusà, Marco Giovanni; Villa, Igor Maria; Vezzoli, Giovanni; Garzanti, Eduardo

2010-05-01

Tectonic reconstructions performed in recent years are increasingly based on petrographic (Dickinson & Suczek, 1979; Garzanti et al., 2007) and geochronological (Brandon et al., 1998; DeCelles et al., 2004) analyses of detrital systems. Detrital age patterns are traditionally interpreted as a result of cooling induced by exhumation (Jäger, 1967; Dodson, 1973). Such an approach can lead to infer extremely high erosion rates (Giger & Hurford 1989) that conflict with compelling geological evidence (Garzanti & Malusà, 2008). This indicates that interpretations solely based on exhumational cooling may not have general validity (Villa, 2006). Here we propose a new detrital geochronology model that takes into account the effects of both crystallization and exhumational cooling on geochronometers, from U-Pb on zircon to fission tracks on apatite. This model, specifically designed for unroofing magmatic complexes, predicts both stationary and moving mineral-age peaks. Because its base is the ordinary interaction between endogenic and exogenic processes, it is applicable to any geological setting. It was tested on the extremely well-studied Bregaglia-Bergell pluton in the Alps, and on the sedimentary succession derived from its erosion. The consistency between predicted and observed age patterns validates the model. Our results demonstrate that volcanoes were active on top of the growing Oligocene Alps, and resolve a long-standing paradox in quantitative erosion-sedimentation modelling, the scarcity of sediment during apparently fast erosion. Dickinson, W. R. & Suczek, C. A. Plate tectonics and sandstone composition. Am. Assoc. Petrol. Geol. Bull. 63, 2164-2172 (1979). Garzanti, E., Doglioni, C., Vezzoli. G. & Andò, S. Orogenic belts and orogenic sediment provenance. J. Geol. 115, 315-334 (2007). Brandon, M. T., Roden-Tice, M. K. & Garver, J. I. Cenozoic exhumation of the Cascadia accretionary wedge in the Olympic Mountains, northwest Washington State. Geol. Soc. Am. Bull. 110, 985-1009 (1998). DeCelles, P. G., Gehrels, G. E., Najman, Y., Martin, A. J., Carter, A., Garzanti, E. Detrital geochronology and geochemistry of Cretaceous-Early Miocene strata of Nepal: implications for timing and diachroneity of initial Himalayan orogenesis. Earth Planet. Sci. Lett. 227, 313-330 (2004). Jäger, E. in Rb-Sr Altersbestimmungen an Glimmern der Zentralalpen, Beitr. Geol. Karte Schweiz NF 134 (eds. Jäger, E., Niggli, E. & Wenk, E.) 28-31 (Bern, Kümmerly & Frey, 1967). Dodson, M. H. Closure temperature in cooling geochronological and petrological systems. Contr. Miner. Petrol. 40, 259-274 (1973). Giger, M. & Hurford, A. J. Tertiary intrusives of the Central Alps: their Tertiary uplift, erosion, redeposition and burial in the south-alpine foreland. Eclogae geol. Helv. 82, 857-866 (1989). Garzanti, E. & Malusà, M. G. The Oligocene Alps: Domal unroofing and drainage development during early orogenic growth. Earth Planet. Sci. Lett. 268, 487-500 (2008). Villa, I. M. From nanometer to megameter: Isotopes, atomic-scale processes, and continent-scale tectonic models. Lithos 87, 155-173 (2006).

Exposure to particles, elemental carbon and nitrogen dioxide in workers exposed to motor exhaust.

PubMed

Lewné, Marie; Plato, Nils; Gustavsson, Per

2007-11-01

The main aim of this study was to investigate the personal exposure to diesel and petrol exhaust fumes in occupations when exposure is prevalent and/or high. We also investigated the correlation between the five particle fractions [particles with an aerodynamic diameter <1 microm (PM(1)), particles with an aerodynamic diameter <2.5 microm (PM(2.5)), particles in size 0.1-10 microm, elemental carbon (EC) and total carbon (TC)] and nitrogen dioxide (NO(2)), in the various occupational environments. Seventy-one workers were included in the study. They were subdivided into seven groups depending on working area, working indoors, out of doors or in vehicles and type of exposure (diesel or petrol exhaust). Personal measurements were performed during 3 days per worker. We used five indicators of the particle fraction: PM(1), PM(2.5), particle measured with a real-time monitoring instrument for particles in sizes 0.1 and 10 microm (DataRAM), EC and TC. We used NO(2) as an indicator of the gas phase. Tunnel construction workers showed the highest levels of exposure for all indicators, followed by diesel-exposed garage workers. For the other five groups, the levels were statistically significantly lower, and the differences between the groups were small. The full-shift geometric average of PM(1) varied between 119 microg m(-3) (tunnel construction workers) and 11 microg m(-3) (taxi drivers). For PM(2.5), the levels varied between 231 microg m(-3) (tunnel construction workers) and 16 microg m(-3) (bus and lorry drivers). For the measurements with the real-time monitoring instrument DataRAM, the levels varied between 398 microg m(-3) (tunnel construction workers) and 14 microg m(-3) (taxi drivers). For EC, the levels varied between 87 microg m(-3) (tunnel construction workers) and 4 microg m(-3) (other outdoor workers exposed to diesel exhaust), and for TC, the levels varied between 191 microg m(-3) (tunnel construction workers) and 10 microg m(-3) (taxi drivers). Finally, for NO(2), the levels varied between 350 microg m(-3) (tunnel construction workers) and 32 microg m(-3) (other outdoor workers exposed to diesel exhaust). For the indoor workers exposed to diesel exhaust fumes only, all the indicators correlated comparatively well and statistically significantly to each other (r(2) = 0.44-0.89). For the other groups, correlations were lower and showed no consistent pattern. The tunnel construction workers had exposure levels for all indicator substances that were considerably and significantly higher than for the other groups. The NO(2) levels were higher for indoor workers exposed to diesel exhaust than for all other groups (except tunnel construction workers). All particle fractions, as well as NO(2) correlated well in occupations with indoor exposure to diesel exhaust.

Drilling the Bushveld Complex- the world's largest layered mafic intrusion

NASA Astrophysics Data System (ADS)

Ashwal, L. D.; Webb, S. J.; Trumbull, R. B.

2013-12-01

The fact that surprising new discoveries can be made in layered mafic intrusions (e.g., subtle 100-150 m cyclicity in apparently homogeneous cumulates over 1000s of m) means that we are still in the first-order characterization phase of understanding these objects. Accordingly, we have secured funding from ICDP for a planning workshop to be held in Johannesburg in early 2014, aimed at scientific drilling of the Bushveld Complex, the world's largest layered mafic intrusion. Science objectives include, but are not limited to: 1. Magma chamber processes & melt evolution. How many melts/magmas/mushes were involved, what were their compositions and how did they interact? What, if anything, is missing from the Complex, and where did it go? Did Bushveld magmatism have an effect upon Earth's atmosphere at 2 Ga? 2. Crust-mantle interactions & origin of Bushveld granitoids. Are Bushveld granites & rhyolites crustal melts, differentiates from the mafic magmas or products of immiscibility? How can the evolved isotopic signatures in the mafic rocks (e.g., epsilon Nd to -8) be understood? 3. Origin of ore deposits. What were the relative roles of gravity settling, magma mixing, immiscibility and hydrothermal fluid transport in producing the PGE, Cr and V deposits? We have identified 3 potential drilling targets representing a total of ~12 km of drill core. Exact locations of drill sites are to be discussed at the workshop. Target A- East-Central Bushveld Complex. We propose 3 overlapping 3 km boreholes that will provide the first roof-to-floor continuous coverage of the Rustenburg Layered Suite. These boreholes will represent a curated, internationally available reference collection of Bushveld material for present and future research. Target B- Southeastern Bushveld Complex. We propose a single borehole of ~2 km depth, collared in Rooiberg felsite, and positioned to intersect the Roof Zone, Upper Zone, Main Zone and floor of the Complex. Amongst other things, this site will evaluate the latest differentiates of the Complex: are they represented by felsic Rooiberg lavas (Van Tongeren & Mathez, 2012 J. Petrol. 51, 1891), or a newly-discovered sequence of hornblende quartz monzonites (Cawthorn, 2013, J. Petrol., in press)? Target C- Northern Lobe of Bushveld Complex. We propose 2 shorter ~500 m boreholes sited to (a) fill in missing stratigraphy of 2 existing deep cores (Bellevue & Moordkopje) including the unique 200 m thick troctolitic horizon in the Main Zone, and (b) to study the transgressive Main Zone - Upper Zone boundary several km north of the Bellevue/Moordkopje sites. All boreholes are intended to provide continuous down-hole geophysical measurements including magnetic susceptibility, density, electrical conductivity and radiometric data. There is also potential to obtain deep fluids and gases for biogeochemical and other studies. All interested geoscientists are welcome to attend the workshop. Watch the ICDP website for announcements (www.icdp-online.org).

Internally consistent thermodynamic data for high-pressure and ultrahigh-pressure phases in the system CaO-MgO-Al2O3-SiO2-H2O

NASA Astrophysics Data System (ADS)

Grevel, K. D.

2008-12-01

In order to enable reliable calculations of phase relations among high-pressure phases the Berman [1] data set was augmented by data for the high-pressure phases stishovite (stv), topaz-OH (toz-OH), phase pi (pi), Mg-staurolite (Mg-st), Mg-sursassite (Mg-sur), and Mg-chloritoid (Mg-cld) using a similar optimization technique as described by Berman et al. [2]. The data of several other phases of the system CaO-MgO- Al2O3-SiO2-H2O obtained in the Berman data base were slightly refined to keep the consistency to the reversal brackets and the originally measured data: andalusite (and), clinochlore (chl), coesite (cs), diaspore (dsp), kaolinite (kln), kyanite (ky), lawsonite (lws), pyrophyllite (prl), sillimanite (sil), zoisite (zo). CP-data were kept constant [1] or estimated [3]. phase; ΔfH0298 (kJ mol-1); S0298 (J K-1 mol-1); V0298 (J K-1 mol-1); v1×105 (bar-1); v2×1012 (bar-2); v3×105 (K-1); v4×108 (K-2) and; -2589.857; 91.47; 5.146; -0.0653; 0.000; 2.291; 0.170 chl; -8903.532; 437.92; 21.000; -0.1328; 3.837; 2.142; 0.962 Mg-cld; -3551.657; 142.20; 6.874; -0.0692; 0.000; 2.544; 0.000 cs; -907.510; 39.63; 2.064; -0.0998; 1.823; 0.620; 0.960 dsp; -999.115; 35.22; 1.776; -0.0719; 0.629; 3.245; 0.684 kln; -4119.400; 204.18; 9.952; -0.1200; 0.000; 3.200; 0.000 ky; -2593.767; 82.71; 4.408; -0.0593; 1.021; 1.730; 0.787 lws; -4866.665; 228.04; 10.155; -0.0825; 0.000; 3.339; 0.000 Mg-sur; -13907.329; 608.39; 26.888; -0.0826; 0.923; 3.187; 0.087 pi; -9586.742; 403.23; 18.559; -0.0678; 0.000; 2.254; 0.000 prl; -5640.501; 239.43; 12.782; -0.1800; 0.000; 2.621; 0.000 sil; -2586.169; 95.40; 4.984; -0.0601; 1.341; 1.138; 0.605 Mg-st; -24998.289; 944.53; 44.260; -0.0579; 0.000; 2.017; 0.000 stv; -870.861; 25.59; 1.401; -0.0318; 0.000; 1.849; 0.000 toz-OH; -2885.939; 117.40; 5.352; -0.0630; 0.000; 1.938; 0.000 zo; -6889.494; 297.20; 13.565; -0.0695; 0.000; 2.752; 0.000 References [1] R.G. Berman, J. Petrol., 1988, 29, 445 [2] R.G. Berman et al., J. Petrol., 1986, 27, 1331 [3] R.G. Berman, T.H. Brown, Con. Min. Pet., 1985, 89, 168

The Role of Brines in the Fluid Induced Dehydration of the Mafic Lower Crust from Amphibolite to Granulite Grade: Nature and Experiment

NASA Astrophysics Data System (ADS)

Harlov, D. E.

2016-12-01

Natural evidence for the role of low H2O activity fluids (CO2 or concentrated brines) in the dehydration of H2O-rich, mafic amphibolite-facies rocks to H2O-poor, Opx-bearing granulite-facies rocks (700-900 °C and 500-1000 MPa) for both highly localised dehydration zones (CO2; cm's) (Harlov et al. 2006, J Petrol, 47, 3) as well as regional terranes (NaCl-KCl brines; km's) (Harlov and Förster 2002, J Petrol, 43, 769; Hansen and Harlov 2007, 48, 1641) include the presence of Kfs micro-veins along Qtz-Plg grain boundaries; Plg grains metasomatised in a K-rich fluid; Mnz and/or Xn inclusions in the FAp grains; Bt enriched in Ti, F, and Cl; and FAp enriched in Cl and F. These features are not seen in the "source" amphibolite facies terrane along the same traverse. When log(fHF/fH2O) for either Bt or FAp is plotted as a function of the distance from the fluid/heat source, a uniform decrease in log(fHF/fH2O) is observed across the granulite to amphibolite facies traverse suggesting the presence of a uniform low H2O activity uniform fluid front. Dehydration experiments (900 °C; 1000 MPa; 3 weeks; Au capsule; quenched) involving a cylinder of natural tonalitic Bt gneiss (Plg, Qtz, Bt) (220 mg) and a concentrated KCl brine (20-30 % H2O; 70-80 % KCl) (8 mg) placed at the base of the cylinder have been conducted in the piston cylinder apparatus (CaF2 setup). Micro-veins primarily of Kfs, with some evidence of partial melting, formed along Qtz/Plg grain boundaries though only where Bt and Qtz were in contact. Here the Bt reacted with Qtz to form numerous small Opx and Cpx grains as well as minor Ilm from the 2-3 wt % of TiO2 present in the Bt. The two principle reactions responsible for both the formation of the Kfs micro-veins as well as the pyroxenes include: (1) An (in Plg) + Qtz + KCl (in fluid) = Kfs + CaCl2 (in fluid) and (2) Bt + Qtz = Opx + Kfs + H2O. The same experiment performed under the same P-T conditions involving either a concentrated NaCl brine (20-30 % H2O; 70-80 % NaCl) or a CO2-rich fluid (80 % CO2, 20 % H2O) or a fluid absent dry melt resulted in micro-veins approximating a granitic composition along Qtz/Plg grain boundaries with numerous small Opx grains minor Ilm forming along biotite grain boundaries, again only when the Bt and Qtz were in contact. Due to an absence of KCl in these three cases, only reaction (2) was relevant.

On the time course of lexical stress priming in speech production: Behavioral and ERPs evidence from a free-stress language.

PubMed

Sulpizio, Simone; Vespignani, Francesco; Job, Remo

2016-10-01

The goal of the present research was to study the time course of lexical stress encoding in a free-stress language with unpredictable stress. To this aim we measured event-related brain potentials (ERPs) during lexical priming. Participants named pictures bearing either the dominant or non-dominant stress pattern, and preceded by either a congruent or an incongruent word prime (e.g., CInema-FRAgola'cinema-strawberry' vs. benZIna-FRAgola'petrol-strawberry'). Behavioral results show that participants were slower in naming targets that had the same stress pattern as the prime, and were also faster in producing words with the dominant stress pattern in the language. The electrophysiological results show that both the effects are compatible with the time course of phonological encoding in speech production. Surprisingly, a dominant stress effect occurred in the ERPs elicited by the primes, with a larger positivity for non-dominant stress words in a 150-250ms time-window. The pattern of results indicates that during speech production: a) the system is sensitive to the stress patterns distribution; b) the automatic pre-activation of a metrical frame may interfere with the phonological encoding of a to-be-uttered word. Copyright © 2016 Elsevier B.V. All rights reserved.

[The new migratory deal in Southern Europe].

PubMed

Simon, G

1986-09-01

The author examines migration patterns in Southern Europe during the 1970s and early 1980s, noting particularly the reduction in migration northward from this region. It is noted that "departure potential remains sizable in certain areas of Portugal, Spain, Southern Italy, and most particularly, of Turkey and Yugoslavia. Transoceanic migrations have by no means ceased, as new flows of skilled labor have, since 1974, gone towards Arab states endowed with petrol (oil) revenues. And yet, the paramount fact is most surely the emergence and the proliferation in Greece, Spain, and (especially) in Italy, of basically clandestine (illegal) immigration. This movement is due to the convergence of several factors: economic and demographic disparities between northern and southern shores of the Mediterranean Sea, the sealing-off of borders in Northwestern Europe and the 'carry-over' effect upon nations of 'transit', the extent of the flow of refugees, and--most particularly--the appeal provided by the development, in these new employer countries, of an underground economy accompanied by the extension into industry of the practice of 'undeclared' work. And notwithstanding the series of rules lastly drawn up in Spain and in Greece, such forms of clandestine (unauthorized) migration appear highly likely--to say the least--to persist." (SUMMARY IN ENG AND SPA) excerpt

Minor access control of Hong Kong under the Framework Convention on Tobacco Control.

PubMed

Kan, Ming-yue; Lau, Maggie

2010-05-01

Asia's tobacco control movement was strengthened owing to the need to fulfill the Framework Convention on Tobacco Control (FCTC). The present study aims to assess the compliance rates of tobacco retailers to the law forbidding the sales of tobacco to minors in Hong Kong before and after the growth of the tobacco control movement brought by the enactment of the newly amended tobacco control law with effect from 2007. The legislation was enacted to fulfill the FCTC. Two waves of territory-wide compliance checks conducted in 2006 and 2008 were compared. The compliance check was conducted using Standard Protocol. The overall compliance rate was still low though it increased from 18.9% in 2006 to 27.0% in 2008. The compliance rate of convenience stores and newspaper stands improved whereas the rate for restaurants, grocery stores and petrol stations worsened. Less tobacco retailing outlets displayed a specified warning sign required in 2008 (33.7%) comparing to 2006 (41.4%). The indoor smoking ban of the FCTC unintentionally changed the cigarette retailing landscape and finally improved the compliance rate. The case study also demonstrated that the Asia region still has much room for improvement in fulfilling the FCTC in term of effective implementation and enforcement. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.

I.C. Engine emission reduction by copper oxide catalytic converter

NASA Astrophysics Data System (ADS)

Venkatesan, S. P.; Shubham Uday, Desai; Karan Hemant, Borana; Rajarshi Kushwanth Goud, Kagita; Lakshmana Kumar, G.; Pavan Kumar, K.

2017-05-01

The toxic gases emitted from diesel engines are more than petrol engines. Predicting the use of diesel engines, even more in future, this system is developed and can be used to minimize the harmful gases. Toxic gases include NOX, CO, HC and Smoke which are harmful to the atmosphere as well as to the human beings. The main aim of this work is to fabricate system, where the level of intensity of toxic gases is controlled through chemical reaction to more agreeable level. This system acts itself as an exhaust system; hence there is no needs to fit separate the silencer. The whole assembly is fitted in the exhaust pipe from engine. In this work, catalytic converter with copper oxide as a catalyst, by replacing noble catalysts such as platinum, palladium and rhodium is fabricated and fitted in the engine exhaust. With and without catalytic converter, the experimentations are carried out at different loads such as 0%, 25%, 50%, 75%, and 100% of maximum rated load. From the experimental results it is found that the maximum reduction is 32%, 61% and 21% for HC, NOx and CO respectively at 100% of maximum rated load when compared to that of without catalytic converter. This catalytic converter system is cash effective and more economical than the existing catalytic converter.

IRIS Toxicological Review and Summary Documents for ...

EPA Pesticide Factsheets

Carbon tetrachloride is a volatile haloalkane with a wide range of industrial and chemical applications. It is produced commercially from chlorination of a variety of low molecular weight hydrocarbons such as carbon disulfide, methanol, methane, propane, and ethylene dichloride. It is also produced by thermal chlorination in the production of tetrachloroethylene. Major uses of carbon tetrachloride have been in the recovery of tin from tin plating waste, in formulation of petrol additives and refrigerants, in metal degreasing and agricultural fumigants, in chlorination of organic compounds, in the production of semiconductors, in the reduction of fire hazard, as a solvent for rubber cement, and as a catalyst in polymer technology. Its production has been decreasing and it is no longer permitted in products intended for home use. Despite this ban, carbon tetrachloride has been detected at 314 hazardous waste sites. EPA's assessment of noncancer health effects and carcinogenic potential of carbon tetrachloride was last prepared and added to the IRIS database in 1991. The IRIS program is preparing an assessment that will incorporate health effects information available for carbon tetrachloride, and current risk assessment methods. The IRIS assessment for carbon tetrachloride will consist of a Toxicological Review and IRIS Summary. The Toxicological Review is a critical review of the physiochemical and toxicokinetic properties of a chemical, and its toxicity

Lead exposure in adult males in urban Transvaal Province, South Africa during the apartheid era.

PubMed

Hess, Catherine A; Cooper, Matthew J; Smith, Martin J; Trueman, Clive N; Schutkowski, Holger

2013-01-01

Human exposure to lead is a substantial public health hazard worldwide and is particularly problematic in the Republic of South Africa given the country's late cessation of leaded petrol. Lead exposure is associated with a number of serious health issues and diseases including developmental and cognitive deficiency, hypertension and heart disease. Understanding the distribution of lifetime lead burden within a given population is critical for reducing exposure rates. Femoral bone from 101 deceased adult males living in urban Transvaal Province (now Gauteng Province), South Africa between 1960 and 1998 were analyzed for lead concentration by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Of the 72 black and 29 white individuals sampled, chronic lead exposure was apparent in nearly all individuals. White males showed significantly higher median bone lead concentration (ME = 10.04 µg·g(-1)), than black males (ME = 3.80 µg·g(-1)) despite higher socioeconomic status. Bone lead concentration covaries significantly, though weakly, with individual age. There was no significant temporal trend in bone lead concentration. These results indicate that long-term low to moderate lead exposure is the historical norm among South African males. Unexpectedly, this research indicates that white males in the sample population were more highly exposed to lead.

Assessment of air quality after the implementation of compressed natural gas (CNG) as fuel in public transport in Delhi, India.

PubMed

Ravindra, Khaiwal; Wauters, Eric; Tyagi, Sushil K; Mor, Suman; Van Grieken, René

2006-04-01

Public transport in Delhi was amended by the Supreme Court of India to use Compressed Natural Gas (CNG) instead of diesel or petrol. After the implementation of CNG since April 2001, Delhi has the highest fraction of CNG-run public vehicles in the world and most of them were introduced within 20 months. In the present study, the concentrations of various criteria air pollutants (SPM, PM(10), CO, SO(2) and NO(x)) and organic pollutants such as benzene, toluene, xylene (BTX) and polycyclic aromatic hydrocarbons (PAHs) were assessed before and after the implementation of CNG. A decreasing trend was found for PAHs, SO(2) and CO concentrations, while the NO(x) level was increased in comparison to those before the implementation of CNG. Further, SPM, PM(10), and BTX concentrations showed no significant change after the implementation of CNG. However, the BTX concentration demonstrated a clear relation with the benzene content of gasoline. In addition to the impact of the introduction of CNG the daily variation in PAHs levels was also studied and the PAHs concentrations were observed to be relatively high between 10 pm to 6 am, which gives a proof of a relation with the limited day entry and movement of heavy vehicles in Delhi.

Durability of switchable QR code carriers under hydrolytic and photolytic conditions

NASA Astrophysics Data System (ADS)

Ecker, Melanie; Pretsch, Thorsten

2013-09-01

Following a guest diffusion approach, the surface of a shape memory poly(ester urethane) (PEU) was either black or blue colored. Bowtie-shaped quick response (QR) code carriers were then obtained from laser engraving and cutting, before thermo-mechanical functionalization (programming) was applied to stabilize the PEU in a thermo-responsive (switchable) state. The stability of the dye within the polymer surface and long-term functionality of the polymer were investigated against UVA and hydrolytic ageing. Spectrophotometric investigations verified UVA ageing-related color shifts from black to yellow-brownish and blue to petrol-greenish whereas hydrolytically aged samples changed from black to greenish and blue to light blue. In the case of UVA ageing, color changes were accompanied by dye decolorization, whereas hydrolytic ageing led to contrast declines due to dye diffusion. The Michelson contrast could be identified as an effective tool to follow ageing-related contrast changes between surface-dyed and laser-ablated (undyed) polymer regions. As soon as the Michelson contrast fell below a crucial value of 0.1 due to ageing, the QR code was no longer decipherable with a scanning device. Remarkably, the PEU information carrier base material could even then be adequately fixed and recovered. Hence, the surface contrast turned out to be the decisive parameter for QR code carrier applicability.

Chemical exposures and respiratory cancer among Finnish woodworkers.

PubMed Central

Kauppinen, T P; Partanen, T J; Hernberg, S G; Nickels, J I; Luukkonen, R A; Hakulinen, T R; Pukkala, E I

1993-01-01

A case-control study of respiratory cancer, nested within a cohort of male woodworkers, was updated in Finland. The update extended the initial follow up of 3805 workers from 19 plants to 7307 workers from 35 plants. Each case of respiratory cancer (n = 136) diagnosed between 1957 and 1982 within the cohort was matched by year of birth with three controls (n = 408) from the cohort. Chemical exposures were assessed for the cases and the controls by a plant and period specific job exposure matrix. An excess of respiratory cancer was associated with phenol. Concomitant exposures to several other agents occurred as well, however, and no exposure-response relation for phenol was seen. An excess risk and an increasing exposure-response relation were found for engine exhaust from petrol and diesel driven factory trucks. The excess risk associated with pesticides was lower than in our previous study, an indication of qualitative and quantitative differences in exposure between the initial and augmented cohorts. Slightly increased risks were found for terpenes and mould spores, which may be due to chance although the contribution of occupational exposure cannot be ruled out. Exposure to wood dust, mainly from pine, spruce and birch, at a level of about 1 mg/m3, was not associated with lung cancer, upper respiratory cancer, or adenocarcinoma of the lung. PMID:8435346

Volatile Organic Compounds: Characteristics, distribution and sources in urban schools

NASA Astrophysics Data System (ADS)

Mishra, Nitika; Bartsch, Jennifer; Ayoko, Godwin A.; Salthammer, Tunga; Morawska, Lidia

2015-04-01

Long term exposure to organic pollutants, both inside and outside school buildings may affect children's health and influence their learning performance. Since children spend significant amount of time in school, air quality, especially in classrooms plays a key role in determining the health risks associated with exposure at schools. Within this context, the present study investigated the ambient concentrations of Volatile Organic Compounds (VOCs) in 25 primary schools in Brisbane with the aim to quantify the indoor and outdoor VOCs concentrations, identify VOCs sources and their contribution, and based on these; propose mitigation measures to reduce VOCs exposure in schools. One of the most important findings is the occurrence of indoor sources, indicated by the I/O ratio >1 in 19 schools. Principal Component Analysis with Varimax rotation was used to identify common sources of VOCs and source contribution was calculated using an Absolute Principal Component Scores technique. The result showed that outdoor 47% of VOCs were contributed by petrol vehicle exhaust but the overall cleaning products had the highest contribution of 41% indoors followed by air fresheners and art and craft activities. These findings point to the need for a range of basic precautions during the selection, use and storage of cleaning products and materials to reduce the risk from these sources.

Self-lubricating Al-WS2 composites for efficient and greener tribological parts.

PubMed

Niste, Vlad Bogdan; Ratoi, Monica; Tanaka, Hiroyoshi; Xu, Fang; Zhu, Yanqiu; Sugimura, Joichi

2017-11-07

Due to their mechanical and physical properties, aluminium alloys possess wide potential in the automotive industry, particularly in hot reciprocating applications such as pistons for diesel and petrol engines. WS 2 particle-reinforced composites could bring further improvements by reducing friction and wear between moving parts. Reducing friction improves efficiency by lowering energy/fuel use, ultimately leading to lower greenhouse gas emissions, while antiwear properties can prolong component life. This study compares for the first time the tribological performance of powder metallurgy-consolidated Al composites reinforced with either IF- or 2H-WS 2 particles, so as to elucidate their mechanism of action in test conditions similar to those encountered in engine applications. The composites were tested in lubricated reciprocating contacts against AISI52100 steel balls and the impact of WS 2 could be seen at both 25 and 100 °C. The reduced friction and wear at ambient temperature is due to the predominantly physical mechanism of action of WS 2 , while the best antiwear performance is measured at elevated (standard operating engine) temperatures that promote the chemical reaction of WS 2 with the aluminium matrix. The investigation focused on studying the wear tracks/scars and the tribofilms generated on the composite and ball with optical profilometry, SEM, XPS and Auger spectroscopy.

Comparison of antimalarial activity of Artemisia turanica extract with current drugs in vivo.

PubMed

Taherkhani, Mahboubeh; Rustaiyan, Abdolhossein; Nahrevanian, Hossein; Naeimi, Sabah; Taherkhani, Tofigh

2013-03-01

The purpose of this study was to compare antimalarial activity of Artemisia turanica Krasch as Iranian flora with current antimalarial drugs against Plasmodium berghei in vivo in mice. Air-dried aerial parts of Iranian flora A. turanica were collected from Khorasan, northeastern Iran, extracted with Et2O/MeOH/Petrol and defatted. Toxicity of herbal extracts was assessed on male NMRI mice, and their antimalarial efficacy was compared with antimalarial drugs [artemether, chloroquine and sulfadoxinepyrimethamine (Fansidar)] on infected P. berghei animals. All the groups were investigated for parasitaemia, body weight, hepatomegaly, splenomegaly and anemia. The significance of differences was determined by Analysis of Variances (ANOVA) and Student's t-test using Graph Pad Prism software. The inhibitory effects of A. turanica extract on early decline of P. berghei parasitaemia highlights its antimalarial activity, however, this effect no longer can be observed in the late infection. This may be due to the metabolic process of A. turanica crude extract by mice and reduction of its concentration in the body. Crude extract of A. turanica represented its antisymptomatic effects by stabilization of body, liver and spleen weights. This study confirmed antimalarial effects of A. turanica extracts against murine malaria in vivo during early infection, however, there are more benefits on pathophysiological symptoms by this medication.

Occupational Exposure of Diesel Station Workers to BTEX Compounds at a Bus Depot

PubMed Central

Moolla, Raeesa; Curtis, Christopher J.; Knight, Jasper

2015-01-01

Diesel fuel is known to emit pollutants that have a negative impact on environmental and human health. In developing countries like South Africa, attendants are employed to pump fuel for customers at service stations. Attendants refuel vehicles with various octane unleaded fuel, lead-replacement petrol and diesel fuel, on a daily basis. Attendants are at risk to adverse health effects associated with the inhalation of volatile organic compounds released from these fuels. The pollutants released include benzene, toluene, ethylbenzene and xylenes (BTEX), which are significant due to their high level of toxicity. In this study, a risk assessment of BTEX was conducted at a diesel service station for public buses. Using Radiello passive samplers, it was found that benzene concentrations were above recommended international standards. Due to poor ventilation and high exposure duration, the average benzene concentration over the sampling campaign exceeded the US Environmental Protection Agency’s chronic inhalation exposure reference concentration. Lifetime cancer risk estimation showed that on average there is a 3.78 × 10−4 cancer risk, corresponding to an average chronic daily intake of 1.38 × 10−3 mg/kg/day of benzene exposure. Additionally, there were incidences where individuals were at potential hazard risk of benzene and toluene that may pose non-carcinogenic effects to employees. PMID:25872020

Occupational exposure of diesel station workers to BTEX compounds at a bus depot.

PubMed

Moolla, Raeesa; Curtis, Christopher J; Knight, Jasper

2015-04-13

Diesel fuel is known to emit pollutants that have a negative impact on environmental and human health. In developing countries like South Africa, attendants are employed to pump fuel for customers at service stations. Attendants refuel vehicles with various octane unleaded fuel, lead-replacement petrol and diesel fuel, on a daily basis. Attendants are at risk to adverse health effects associated with the inhalation of volatile organic compounds released from these fuels. The pollutants released include benzene, toluene, ethylbenzene and xylenes (BTEX), which are significant due to their high level of toxicity. In this study, a risk assessment of BTEX was conducted at a diesel service station for public buses. Using Radiello passive samplers, it was found that benzene concentrations were above recommended international standards. Due to poor ventilation and high exposure duration, the average benzene concentration over the sampling campaign exceeded the US Environmental Protection Agency's chronic inhalation exposure reference concentration. Lifetime cancer risk estimation showed that on average there is a 3.78 × 10-4 cancer risk, corresponding to an average chronic daily intake of 1.38 × 10-3 mg/kg/day of benzene exposure. Additionally, there were incidences where individuals were at potential hazard risk of benzene and toluene that may pose non-carcinogenic effects to employees.

Concentrations and sources of cadmium, copper, lead and zinc in house dust in Christchurch, New Zealand.

PubMed

Kim, N; Fergusson, J

1993-09-30

The amounts (microgram m-2) and concentrations (microgram g-1) of cadmium, copper, lead and zinc have been measured in house dust in Christchurch, New Zealand. For 120 houses surveyed the geometric mean concentrations of the four metals are 4.24 micrograms g-1, 165 micrograms g-1, 573 micrograms g-1 and 10,400 micrograms g-1, respectively. In addition eleven variables, such as house age, carpet wear and traffic density, were recorded for each property and the results analysed with respect to their effects on the amounts and concentrations of the four elements. The amounts of all the metals were highly correlated with the overall dustiness of the houses, which was found to be predominantly determined by the degree of carpet wear. No one dominant source of cadmium was identified, although several minor sources including carpet wear, galvanized iron roofs and red/orange/yellow coloured carpets were implicated. Petrol lead and lead-based paints were identified as significant sources of lead in house dust. Rubber carpet underlays or backings were identified as a significant source of zinc, with some contribution from galvanized iron roofs. Road traffic and probably the existence of a fire place appear to contribute to the copper levels.

A decade of drilling developments pays off in offshore Italian oil field

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dussert, P.; Santoro, G.; Soudet, H.

1988-02-29

As the only oil field in the world producing systematically through horizontal wells, Rospo Mare, the Italian oil field in the Adriatic, is s ''first.'' Rospo Mare is an uncommon oil field because the nature of its reservoir and the characteristics of its oil prevent it from being produced through conventional vertical wells. But thanks to horizontal drilling techniques developed since 1977 by Elf Aquitaine and the Institut Francaise du Petrole (IFP), the field was producing 22,00 b/d of crude oil on Jan. 1, 1988. Of this, 19,000 b/d came from six horizontal wells and 3,000 b/d from three verticalmore » or deviated wells. For comparison, on Jan. 1, 1987, the field produced only 4,300 b/d through a single horizontal well, two vertical wells, and one deviated well. Rospo Mare is a joint venture of Elf Italiana (61.7%), the operator, and AGIP (38.3%). A description in this article of the challenge of Rospo Mare and the results to date set the stage for a series of articles in coming weeks. They will cover the state of the art in not only drilling, but horizontal completions, production, log interpretation, and other aspects of this major oil industry technology.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Grubbs, Robert H

Over the past decade, a new family of homogeneous metathesis catalysts has been developed that will tolerate most organic functionalities as well as water and air. These homogeneous catalysts are finding numerous applications in the pharmaceutical industry as well as in the production of functional polymers. In addition the catalysts are being used to convert seed oils into products that can substitute for those that are now made from petroleum products. Seed oils are unsaturated, contain double bonds, and are a ready source of linear hydrocarbon fragments that are specifically functionalized. To increase the number of applications in the areamore » of biomaterial conversion to petrol chemicals, the activity and efficiency of the catalysts need to be as high as possible. The higher the efficiency of the catalysts, the lower the cost of the conversion and a larger number of practical applications become available. Active supported catalysts were prepared and tested in the conversion of seed oils and other important starting materials. The outcome of the work was successful and the technology has been transferred to a commercial operation to develop viable applications of the discovered systems. A biorefinery that converts seed oils is under construction in Indonesia. The catalysts developed in this study will be considered for the next generation of operations.« less

Exposure to electric power generator noise among small scale business operators in selected communities in Ibadan, Nigeria.

PubMed

Ana, Godson R E E; Luqman, Yesufu A; Shendell, Derek G; Owoaje, Eme T

2014-11-01

Inadequate and erratic power supplies mean small businesses use electric generators for alternative power. The authors' goal in the study described here was to assess noise from electric generators and impacts in the commercial areas of Agbowo and Ajibode in Ibadan, Nigeria. Noise levels (A-weighted decibels [dBA]) were measured over 12 weeks, three times a day, during the 2010 dry season using a sound level meter. A questionnaire was administered (515 respondents; 304 in Agbowo, 211 in Ajibode) and audiometric measurements were conducted on 40% of respondents. Mean noise levels varied by source (104 ± 7.7 dBA [diesel], 94.0 ± 6.3 dBA [petrol]) and were highest midday (90.6 ± 5.3 dBA [Agbowo], 70.9 ± 6.2 dBA [Ajibode]). Mean noise levels in Agbowo (78.5 ± 3.9 dBA) and Ajibode (65.7 ± 4.4 dBA) exceeded World Health Organization guidelines (65 dBA) for outdoor commercial environments. Working and living in Agbowo was significantly associated with current evidence of hearing impairment (odds ratio: 6.8, 95% confidence interval: 3.4-13.7). Reducing exposure to noise from electric power generators serving urban small businesses and homes is warranted.

Isolation and partial characterization of mutants with elevated lipid content in Chlorella sorokiniana and Scenedesmus obliquus.

PubMed

Vigeolas, Hélène; Duby, Francéline; Kaymak, Esra; Niessen, Guillaume; Motte, Patrick; Franck, Fabrice; Remacle, Claire

2012-11-30

This paper describes the isolation and partial biomass characterization of high triacylglycerol (TAG) mutants of Chlorella sorokiniana and Scenedesmus obliquus, two algal species considered as potential source of biodiesel. Following UV mutagenesis, 2000 Chlorella and 2800 Scenedesmus colonies were screened with a method based on Nile Red fluorescence. Several mutants with high Nile Red fluorescence were selected by this high-throughput method in both species. Growth and biomass parameters of the strongest mutants were analyzed in detail. All of the four Chlorella mutants showed no significant changes in growth rate, cell weight, cell size, protein and chlorophyll contents on a per cell basis. Whereas all contained elevated total lipid and TAG content per unit of dry weight, two of them were also affected for starch metabolism, suggesting a change in biomass/storage carbohydrate composition. Two Scenedesmus mutants showed a 1.5 and 2-fold increased cell weight and larger cells compared to the wild type, which led to a general increase of biomass including total lipid and TAG content on a per cell basis. Such mutants could subsequently be used as commercial oleaginous algae and serve as an alternative to conventional petrol. Copyright © 2012 Elsevier B.V. All rights reserved.

The Solubility of Diopside in Water at 10 to 15 kbar and 650 to 900 C

NASA Astrophysics Data System (ADS)

Macris, C. A.; Manning, C. E.

2005-12-01

Subduction zone fluids play a critical role in mass transfer and mantle-wedge metasomatism, yet little is known about their composition and chemical behavior. One way to better understand these important fluids is to investigate the solubility of minerals at subduction zone conditions. The solubility of diopside in H2O was measured at 10 to 15 kbar, 650 to 900 °C using a piston-cylinder apparatus with NaCl-graphite furnaces. A single gem-quality diopside crystal was placed in an inner Pt capsule, which then was perforated to allow fluid ingress and added with H2O to an outer Pt capsule, which was then sealed. The solubility was determined by the weight loss of the diopside crystals. All charges were carefully examined by SEM for composition and textural characteristics of quench material. SEM analysis revealed that in several experiments small diopside crystals nucleated and grew in the outer capsule or on the walls of the inner capsule due to fluid convection within the charge. These experiments yielded erroneously high solubilities and were omitted from final plots and equation calculations. Diopside was found to dissolve incongruently to forsterite + dissolved species at all conditions investigated. The forsterite occurs as euhedral crystals in pits etched from the diopside grain covering less than 5% of its surface. In addition, long thin wollastonite blades and a layer of SiO2 "mud" form upon quenching of the run. Experiments at 700 °C and varying times showed that diopside plus forsterite plus fluid reached equilibrium by 12 hours. The solubility of diopside + forsterite in H2O increases with increasing pressure and temperature. At 10 kbar, solubility increases from 0.004 molal at 650 °C to 0.012 molal at 900 °C. At 800 °C and 10 to 15 kbar, solubility increases from 0.008 to 0.015 molal. These preliminary data yield the equation: log mdi+fo = -0.7539 + -2135.7/T + 0.6355P, where T is in K and P is in GPa. Because temperature enhances solubility more than pressure in this system, we can predict that as a fluid moves from slab to wedge, which leads to decompression and heating, di+fo solubility will increase. The resulting fluid will be enriched in Ca and Si, but low in Mg. These results are consistent with theoretical predictions on the composition of fluids in equilibrium with eclogites (Manning 1998), experimental investigations on fluid compositions in equilibrium with high-pressure mantle rocks (Schneider and Eggler 1986; Ayers et al. 1997), and vein-mineral assemblages in blueschists and eclogites (e.g., Gao and Klemd 2001; Becker et al. 1999). Ayers J., Dittmer S.K., Layne G.D. (1997) Earth Planet. Sci. Lett. 150:381-398; Becker H., Jockum K.P., Carlson R.W. (1999) Chem. Geol. 160:291-308; Gao J., Klemd R. (2001) Contrib. Mineral. Petrol. 142:1-14; Manning C.E. (1998) Swiss Bull. Mineral. Petrol. 78:225-242; Schneider M.E., Eggler D.H. (1986) Geochim. Cosmochim. Acta 50:711-724

Strain rate and shear stress at the grain scale generated during near equilibrium antigorite dehydration

NASA Astrophysics Data System (ADS)

Padrón-Navarta, José Alberto; Tommasi, Andréa; Garrido, Carlos J.; Mainprice, David; Clément, Maxime

2016-04-01

Dehydration reactions are an outstanding case of mineral replacement reactions because they produce a significant transient fluid-filled porosity. Because fluids are present, these reactions occur by interface-coupled dissolution-precipitation. Under poorly drained conditions corresponding to foliated metamorphic rocks, they generate fluid pressure gradients that evolve in time and space eventually controlling fluid migration [1]. Despite the general agreement on this fact, we still lack of a precise knowledge of the complex coupling between the stresses generated during the reaction and the timescales for mineral growth and how they ultimate control the rate of fluid migration. Constraining these rates is challenge because the timescales of the feedback between fluid flow and mineral growth rates at near equilibrium are beyond the current experimental capabilities. For instance, numerical simulations suggest that the draining times of a dehydration front by compaction are in the order of 10-100 ky [1] difficult to translate into experimental strain rates. On the other hand, the natural record of dehydration reaction might potentially provide unique constrains on this feedback, but we need to identify microstructures related to compaction and quantify them. Features interpreted as due to compaction have been identified in a microstructural study [2] of the first stages of the antigorite dehydration at high-pressure conditions in Cerro del Almirez, Spain (ca. 1.6-1.9 GPa and 630-710 ° C). Compaction features can be mostly observed in the metamorphic enstatite in the form of (1) gradual crystallographic misorientation (up to 16°) of prismatic crystals due to buckling, (3) localized orthoenstatite(Pbca)/low clinoenstatite (P21/c) inversion (confirmed optically and by means of Electron Backscattered Diffraction) and (4) brittle fracturing of prismatic enstatite wrapped by plastically deformed chlorite. The coexistence of enstatite buckling and clinoenstatite lamellae has not been previously reported and offers an unique opportunity to estimate a lower bound for the strain rates and local shear stresses generated during the grain growth and coeval compaction. Estimated values based on experimental creep rates on pyroxene aggregates [3] result in strain rates in the order of 10-12 to 10-13 s-1 and shear stresses of 60-70 MPa. Lower shear stress values (20-40 MPa) are retrieved using the thermodynamic model clinoenstatite inversion of Coe [4] in combination with the hydrostatic high-pressure experimental data on the stability of low clinoenstatite (P21/c). These data suggest that, under low deviatoric stress, fluid extraction and compaction near equilibrium in natural systems are only marginally higher than the strain rate of the solid matrix. These observations support the relatively long residence time of fluids in dehydration fronts and the necessity to further explore and quantify the feedback between mineral grain growth and fluid migration. [1] Connolly (2010) Elements 6(3):165-172; [2] Padrón-Navarta et al. (2015). Contrib Miner Petrol 169:35 [3] Raleigh et al. (1971). J Geophys Res 76(17): 4011-4022; [4] Coe (1970). Contrib Miner Petrol 26(3):247-264

Age of metamorphic events : petrochronology and hygrochronology

NASA Astrophysics Data System (ADS)

Bosse, Valerie; Villa, Igor M.

2017-04-01

Geodynamic models of the lithosphere require quantitative data from natural samples. Time is a key parameter: it allows to calculate rates and duration of geological processes and provides informations about the involved physical processes (Vance et al. 2003). Large-scale orogenic models require linking geochronological data with other parameters: structures, kinematics, magmatic and metamorphic petrology (P-T-A-X conditions), thermobarometric evolution of the lithosphere, chemical dynamics (Muller, 2003). This requires geochronometers that are both powerful chemical and petrological tracers. In-situ techniques allow dating a mineral in its petrological-microstructural environment. Getting a "date" has become quite easy... But what do we date in the end ? What is the link between the numbers obtained from the mass spectrometer and the age of the metamorphic event we are trying to date ? How can we transform the date into a geological meaningful age ? What do we learn about the behavior of the geochronometer minerals? Now that we can perform precise dating on very small samples directly in the studied rock, it is important to improve the way we interpret the ages to give them more pertinence in the geodynamic context. We propose to discuss the Th/U/Pb system isotopic closure in various metamorphic contexts using our published examples of in situ dating on monazite and zircon (Bosse et al. 2009; Didier et al. 2014, 2015). The studied examples show that (i) fluid assisted dissolution-precipitation processes rather than temperature-dependent solid diffusion predominantly govern the closure of the Th/U/Pb system (ii) monazite and zircon are sensitive to the interaction with fluids of specific composition (F, CO2, K ...), even at low temperature (iii) in the absence of fluids, monazite is able to record HT events and to retain this information in poly-orogenic contexts or during partial melting events (iv) complex chemical and isotopic zonations, well known in monazite, reflect the interaction with the surrounding mineral assemblages. An often neglected observation is that the K-Ar chronometer minerals show similar patterns of isotopic inheritance closely tied to relict patches and heterochemical retrogression phases (Villa and Williams 2013). Isotopic closure in the U-Pb and K-Ar systems follows the same principle: thermal diffusion is very slow, dissolution and reprecipitation are several orders of magnitude faster. This means that both U-Pb and K-Ar mineral chronometers are hygrochronometers. The interpretation of the ages of the different domains cannot be decoupled from the geochemical and petrological context. The focus on petrology also requires, following Villa (1998, 2016), that the ages measured in metamorphic rocks no longer can be used in geodynamic models according to the "closure temperature" concept as originally defined by Dodson (1973). Bosse et al. (2009) Chem Geol 261: 286 Didier et al. (2014) Chem Geol 381: 206 Didier et al. (2015) Contrib Mineral Petrol 170: 45 Dodson (1973) Contrib Mineral Petrol 40: 259 Muller (2003) EPSL, 206: 237 Villa (1998) Terra Nova 10: 42 Villa (2016) Chem Geol 420: 1 Villa & Williams (2013) In: Harlov & Austrheim (eds.), Metasomatism and the Chemical Transformation of Rock. Springer, p171

Evidence for metasomatic enrichment in the oceanic lithosphere and implication for the generation of intraplate basalts

NASA Astrophysics Data System (ADS)

Pilet, S.; Buchs, D.; Cosca, M. A.; Baumgartner, P.

2011-12-01

Petrological studies play a significant role in the debate regarding the origin of intraplate magmas by providing unequivocal constraints about the source(s) composition and melting processes related to basalt formation. Two major hypotheses are currently in debate: first, intraplate magmas are produced at depth (i.e. within the asthenosphere) by low-degrees melting of an enriched peridotitic source in the presence of CO2 [1]; second, alkaline magmas are produced by the melting of metasomatic hydrous veins present within the lithospheric mantle [2]. If the existence of metasomatic veins in the continental lithospheric mantle is well documented, their existence and the mechanism of their formation in an oceanic setting are still mostly unconstrained. Here we report new petrological data demonstrating that metasomatic veins can be produced within the oceanic lithosphere by percolation and differentiation of low-degree melts initially located in the low velocity zone [3]. The existence of metasomatic veins in the oceanic lithosphere is documented by cpx xenocrysts in accreted basaltic sills from northern Costa Rica. New field observations, 40Ar-39Ar radiometric dating, biostratigraphic ages and geochemical analyses indicate that the sills represent a possible, ancient analogue of petit-spot volcanoes produced off Japan by oceanic plate flexure [4]. The cpx xenocrysts are interpreted as a relic of metasomatic veins based on their composition, which is similar to that of cpx from metasomatic veins observed in mantle outcrops and xenoliths. The major and trace element contents of the studied cpx xenocrysts indicate that they crystallized at high pressure in a differentiated liquid. This liquid represents the last stage of a fractional crystallization process that produced early anhydrous cumulates followed by later hydrous cumulates, a mechanism similar to that proposed by Harte et al. [5] for the formation of metasomatic veins in the continental lithosphere. Monte Carlo simulation of this process indicates that the differentiation of low degree melts can produce metasomatic cumulates with a mineralogical and chemical composition suitable to be a source for alkaline rocks observed in an oceanic setting [6]. The presence of low degree melts at the base of the lithosphere has been recently suggested to explain the occurrence of the ubiquitous low seismic velocity zone at the base of the oceanic lithosphere [3]. We propose that tectonic processes such as plate flexure [4] or/and small scale mantle convection [7] can allow these melts to percolate and differentiate across the lithosphere to form metasomatic cumulates (i.e. veins). Such cumulates are likely to represent a potential source of alkaline rocks observed in intraplate ocean volcanoes, especially those produced by low volumes of magma. [1] Dasgupta et al. (2007) J. of Petrol. 48, 2093; [2] Pilet et al. (2008) Science 320, 916; [3] Kawakatsu et al. (2009) Science 324, 499; [4] Hirano et al. (2006) Science 313, 1426 ; [5] Harte et al. (1993) Phil. Trans. Royal Soc. of London, Series A 342, 1; [6] Pilet et al. (2011) J. of Petrol. doi:10.1093/petrology/egr007; [7] Ballmer et al. (2009) G3 doi:10.1029/2009GC002386.

The degassing and crystallisation behaviour of basaltic lavas

NASA Astrophysics Data System (ADS)

Applegarth, L. J.; Tuffen, H.; Pinkerton, H.; James, M. R.

2010-12-01

Degassing is a fundamental volcanic process that can play a major role in controlling eruptive styles. Volatile loss during magma ascent and decompression increases the liquidus temperature of the residual melt, resulting in undercooling that can trigger crystallisation (1,2). Late-stage crystallisation and vesiculation are significant factors in controlling the eruptive behaviour of volcanoes of intermediate composition (2), but their effects on basaltic volcanic activity have yet to be fully investigated. We present the results of experiments designed to measure the degassing and crystallisation behaviour of volcanic rocks at temperatures up to 1250°C, using thermo-gravimetric analysis coupled with differential scanning calorimetry and mass spectrometry (TGA-DSC-MS). During TGA-DSC-MS analysis, volatiles released from a sample under a controlled heating programme are identified in a mass spectrometer whilst changes to the sample weight and heat flow are simultaneously recorded. By subjecting samples of basaltic lava and bombs to two heating cycles, we have shown that the onset of degassing (mass loss) is systematically followed by crystallisation (exothermic events) on the first heating cycle. During the second cycle, when the sample has been fully degassed, no mass loss or crystallisation are recorded. Our results also highlight complexities in the processes; in some cases up to four pulses of degassing and crystallisation have been identified during a single heating cycle. Our results allow us to measure the total volatile content of samples, the onset temperatures of degassing and crystallisation and the time lag between the two processes, and the enthalpy, hence percentage, of crystallisation taking place. These results have important implications for our understanding of basaltic volcanic eruptions. During effusive basaltic eruptions, lava can travel many kilometres, threatening property and infrastructure. The final areal flow extent is partly dependent on the highly variable rheology. Cooling strongly affects rheology, but is mainly restricted to thermal boundary layers. Degassing-induced undercooling and crystallisation, however, may alter the bulk rheology (1), and may have contrasting effects. Rapid microlite growth may lead to crystal-crystal interactions, and the development of non-linear rheological properties such as a yield strength (3,4), which will impede advance. Alternatively, the latent heat of crystallisation may reduce the viscosity of the residual melt and suppress further crystal nucleation (5), tending to render the lava more mobile. As yet, the complex effects of degassing on the crystallisation, and hence rheological, behaviour of basaltic melts are not yet sufficiently well constrained for inclusion in the current generation of numerical lava flow models. An improved understanding of these processes is a critical step in improving our ability to forecast flow behaviour. 1. Sparks, R.S.J. and Pinkerton, H. (1978) Nature, 276, 385. 2. Blundy, J. and Cashman, K.V. (2001) Contrib. Mineral. Petrol. 140, 631. 3. Marsh, B.D. (1981) Contrib. Mineral. Petrol. 78, 85. 4. Bagdassarov, N. and Pinkerton, H. (2004) J. Volcanol. Geotherm. Res. 132, 115. 5. Brandeis, G., Jaupart, C., and Allegre, C.J. (1984) J. Geophys. Res. 89(B12), 10161.

Archaean and Palaeoproterozoic metamorphic events in the Orekhov-Pavlograd compressional zone, Ukrainian Shield

NASA Astrophysics Data System (ADS)

Yurchenko, A. V.

2012-04-01

The Orekhov-Pavlograd zone (OPZ) is located between the Mesoarchaean-Neoarchaean Middle Dnieper Province and the Mesoarchaean-Palaeoproterozoic Azov Province in the eastern Ukrainian Shield. The OPZ consists of Archaean and Palaeoproterozoic high-grade metamorphic rocks. According U-Pb isotope analyses Archaean methaigneous rocks have age of 3.5-3.3 Ga, and latest AR events dated form both individual grains and metamorphic rims in the tonalite and the granitic vein occurred at about 2.88 Ga ego. Paleoproterozoic zircons from a hornblende granulite have a concordia age of 2.08 Ga [1]. P-T conditions of the 3.5-3.3 Ga processes calculated from the Ti content in zircon are of 730-760°C. Metamorphic event dated as 2.88 Ga is more preserved and detected in some amphibolites after mafic dykes. According to different methods of hornblende-plagioclase geothermometry along with Al- and Ti-geobarometry of hornblende, the amphibolites have formed at temperature of 735-749 °C and pressure of 5.2 to 7.8 kbar. P-T conditions of Paleoproterozoic metamorphic processes have been calculated for a Paleoproterozoic high-Al paragneiss and mafic rocks. On the base of the computer software THERIAK-DOMINO [2], near-isothermal decompression from ca. 8.5 to 6.0 kbar at 650 °C and then to 5.8 kbar at 740 °C has been determined for small irregular garnet grains (grs 4-7% and XMg 0.36-0.37) associated with the same biotite and plagioclase. P-T conditions obtained by means of the P-T pseudosection calculation are identical within errors to those defined by the Grt + Bt + Pl + Ozt geothermometer by [3] and the geobarometer by [4], T = 675 °C and P = 5.6 kbar. Temperature and pressure calculated for assemblage Grt-Pl-Opx-Amph-Ilm-Ru (mafic rock) by using the TWEEQU method shows: 1) high values of pressure and temperature (ca. 7 kbar and 800 °C) are linked with the first metamorphic event with Opx-Cpx assemblage, 2) moderate values (ca. 5 kbar and ca. 600 °C) are referred to the second metamorphic event when amphibole was crystallized instead of orthopyroxene. The latest metamorphic reworking took place at P = 3.3-4 kbar and T = ca. 600 °C. The resulting Paleoproterozoic P-T-t path suggests a clockwise P-T evolution of the OPZ area. Preferences: 1. S.B.Lobach-Zhuchenko, Yu.S.Egorova, A.V.Yurchenko, V.V.Balagansky, G.V.Artemenko, V.P.Chekulaev, N.A.Arestova, 2009. Mineralogical Journal (Kiev), 31 (1): 3-10. 2. de Capitani, C., 2005. THERIAK - DOMINO User's Guide, Version 1402005, http://titan. minpet.unibas.ch/minpet/theriak/theruser.html (04/2007). 3. Ferry, J.M., Spear, F.S., 1978. Experimental calibration of the partitioning of Fe and Mg between biotite and garnet. Contrib. Mineral. Petrol. 66, 113-117. 4. Koziol, A.M., Newton, R.C., 1989. Grossular activity-composition relationship in ternary garnets determined by reversed displaced-equilibrium experiments. Contrib. Mineral. Petrol. 103, 423-433.

Was there significant tax evasion after the 1999 50 cent per pack cigarette tax increase in California?

PubMed Central

Emery, S; White, M; Gilpin, E; Pierce, J

2002-01-01

Objectives: Several states, including California, have implemented large cigarette excise tax increases, which may encourage smokers to purchase their cigarettes in other lower taxed states, or from other lower or non-taxed sources. Such tax evasion thwarts tobacco control objectives and may cost the state substantial tax revenues. Thus, this study investigates the extent of tax evasion in the 6–12 months after the implementation of California's $0.50/pack excise tax increase. Design and setting: Retrospective data analysis from the 1999 California Tobacco Surveys (CTS), a random digit dialled telephone survey of California households. Main outcome measures: Sources of cigarettes, average daily cigarette consumption, and reported price paid. Results: Very few (5.1 (0.7)% (±95% confidence limits)) of California smokers avoided the excise tax by usually purchasing cigarettes from non- or lower taxed sources, such as out-of-state outlets, military commissaries, or the internet. The vast majority of smokers purchased their cigarettes from the most convenient and expensive sources: convenience stores/gas (petrol) stations (45.0 (1.9)%), liquor/drug stores (16.4 (1.6)%), and supermarkets (8.8 (1.2)%). Conclusions: Despite the potential savings, tax evasion by individual smokers does not appear to pose a serious threat to California's excise tax revenues or its tobacco control objectives. PMID:12035006

Quantification of Gas Emissions from Refinieries, Gas Stations, Oil Wells and Agriculture using Optical Solar Occultation Flux and Tracer Correlation Methods

NASA Astrophysics Data System (ADS)

Mellqvist, J.; Samuelsson, J.; Marianne, E.; Brohede, S.; Andersson, P.; Johansson, J.; Isoz, O.; Tisopulos, L.; Polidori, A.; Pikelnaya, O.

2016-12-01

Industrial volatile organic compound (VOC) emissions may contribute significantly to ozone formation. In order to investigate how much small sources contribute to the VOC concentrations in the Los Angeles metropolitan area a comprehensive emission study has been carried out on behalf of the South Coast Air Quality Management District (SCAQMD). VOC emissions from major sources such as refineries, oil wells, petrol stations oil depots and oil platforms were measured during September and October 2015 using several unique optical methods, including the Solar Occultation Flux method (SOF) and tracer correlation technique based on extractive FTIR and DOAS combined with an open path multi reflection cell. In addition, measurements of ammonia emissions from farming in Chino were demonstrated. The measurements in this study were quality assured by carrying out a controlled source gas release study and side by side measurements with several other techniques. The results from the field campaign show that the emissions from the above mentioned sources are largely underestimated in inventories with potential impact on the air quality in the Los Angeles metropolitan area. The results show that oil and gas production is a very significant VOC emission source. In this presentation the techniques will be discussed together with the main results from the campaign including the quality assurance work.

The neighbourhood effects of geographical access to tobacco retailers on individual smoking behaviour.

PubMed

Pearce, J; Hiscock, R; Moon, G; Barnett, R

2009-01-01

To investigate whether neighbourhood measures of geographical accessibility to outlets selling tobacco (supermarkets, convenience stores and petrol stations) are associated with individual smoking behaviour in New Zealand. Using geographical information systems, travel times from the population-weighted centroid of each neighbourhood to the closest outlet selling tobacco were calculated for all 38,350 neighbourhoods across New Zealand. These measures were appended to the 2002/03 New Zealand Health Survey, a national survey of 12, 529 adults. Two-level logistic regression models were fitted to examine the effects of neighbourhood locational access upon individual smoking behaviour after controlling for potential individual- and neighbourhood-level confounding factors, including deprivation and urban/rural status. After controlling for individual-level demographic and socioeconomic variables, individuals living in the quartiles of neighbourhoods with the best access to supermarkets (OR 1.23, 95% CI 1.06 to 1.42) and convenience stores (OR 1.19, 95% CI 1.03 to 1.38) had a higher odds of smoking compared with individuals in the worst access quartiles. However, the association between neighbourhood accessibility to supermarkets and convenience stores was not apparent once other neighbourhood-level variables (deprivation and rurality) were included. At the national level, there is little evidence to suggest that, after adjustment for neighbourhood deprivation, better locational access to tobacco retail provision in New Zealand is associated with individual-level smoking behaviour.

Short-term exposure to traffic-related air pollution and daily mortality in London, UK.

PubMed

Atkinson, Richard W; Analitis, Antonis; Samoli, Evangelia; Fuller, Gary W; Green, David C; Mudway, Ian S; Anderson, Hugh R; Kelly, Frank J

2016-01-01

Epidemiological studies have linked daily concentrations of urban air pollution to mortality, but few have investigated specific traffic sources that can inform abatement policies. We assembled a database of >100 daily, measured and modelled pollutant concentrations characterizing air pollution in London between 2011 and 2012. Based on the analyses of temporal patterns and correlations between the metrics, knowledge of local emission sources and reference to the existing literature, we selected, a priori, markers of traffic pollution: oxides of nitrogen (general traffic); elemental and black carbon (EC/BC) (diesel exhaust); carbon monoxide (petrol exhaust); copper (tyre), zinc (brake) and aluminium (mineral dust). Poisson regression accounting for seasonality and meteorology was used to estimate the percentage change in risk of death associated with an interquartile increment of each pollutant. Associations were generally small with confidence intervals that spanned 0% and tended to be negative for cardiovascular mortality and positive for respiratory mortality. The strongest positive associations were for EC and BC adjusted for particle mass and respiratory mortality, 2.66% (95% confidence interval: 0.11, 5.28) and 2.72% (0.09, 5.42) per 0.8 and 1.0 μg/m(3), respectively. These associations were robust to adjustment for other traffic metrics and regional pollutants, suggesting a degree of specificity with respiratory mortality and diesel exhaust containing EC/BC.

Risk factors affecting visual-motor coordination deficit among children residing near a petrochemical industrial estate.

PubMed

Aungudornpukdee, P; Vichit-Vadakan, N

2009-12-01

Thailand has been changed to rapid urbanization and industrialization since 1980s. During 1992 through 1996, the number of industrial factories in Rayong province increased very sharply. The major types of industries are petrol-chemical and plastic production. However, after the petrochemical industry boomed, the higher demand led to an industrial area expansion. The establishment of factories in this area leads to serious environmental and health impacts. The study aims to investigate the factors that affect visual-motor coordination deficit among children, 6-13 years of age, residing near the Petrochemical Industrial Estate, Map Ta Phut, Rayong province. A population-based cross-sectional study was employed for collecting data on neurobehavioral effects using the Digit Symbol Test. The study found one-third of 2,956 children presented with visual-motor coordination deficits. Three factors were identified that caused children to have a higher risk of visual-motor coordination deficits: gender (adjusted OR 1.934), monthly parental income (range of adjusted OR 1.977 - 2.612), and household environmental tobacco smoke (adjusted OR 1.284), while age (adjusted OR 0.874) and living period (adjusted OR 0.954) in study areas were reversed effects on visual-motor coordination deficit among children. The finding indicated that children with visual-motor coordination deficit were affected by gender, monthly parental income, age of children, length of living period, and household environmental tobacco smoke.

Modelling diffusion feedbacks between technology performance, cost and consumer behaviour for future energy-transport systems

NASA Astrophysics Data System (ADS)

Tran, Martino; Brand, Christian; Banister, David

2014-04-01

Emerging technologies will have important impacts on sustainability objectives. Yet little is known about the explicit feedbacks between consumer behaviour and technological change, and the potential impact on mass market penetration. We use the UK as a case-study to explore the dynamic interactions between technology supply, performance, cost, and heterogeneous consumer behaviour and the resulting influence on long term market diffusion. Simulations of competing vehicle technologies indicate that petrol hybrids (HEVs) dominate the market over the long-term because they benefit from improved performance and are able to reach the steep part of the diffusion curve by 2025 while competing technologies remain in the early stages of growth and are easier to displace in the market. This is due to the cumulative build-up of stock and slow fleet turnover creating inertia in the technological system. Consequently, it will be difficult to displace incumbent technologies because of system inertia, cumulative growth in stock, long operational life, and consumer risk aversion to new unproven technologies. However, when accounting for both technological and behavioural change, simulations indicate that if investment can reach 30-40% per annum growth in supply, combined with steady technology improvements, and more sophisticated agent decision making such as accounting for full technology lifecycle cost and performance, full battery electric vehicles could displace the incumbent system by 2050.

Evolution of on-road vehicle exhaust emissions in Delhi

NASA Astrophysics Data System (ADS)

Goel, Rahul; Guttikunda, Sarath K.

2015-03-01

For a 40-year horizon (1990-2030), on-road vehicle exhaust emissions were evaluated, retrospectively and prospectively, for the largest urban agglomeration in India - the Greater Delhi region with a combined population of 22 million in 2011 (Delhi along with Ghaziabad, Noida, Greater Noida, Faridabad and Gurgaon). Emissions of particulate matter, sulfur dioxide, carbon monoxide and volatile organic compounds (VOCs) reached their peak during late 1990s through early 2000s after which they reduced significantly through year 2012. On the other hand, nitrogen oxides (NOx) and carbon dioxide show an increasing trend. The most reduction in emissions between 1998 and 2012 occurred as a result of implementation of four sets of vehicular emission standards, removal of lead, reduction of sulfur content, mandatory retirement of older commercial vehicles, and conversion of diesel and petrol run public transport vehicles to compressed natural gas. In addition, changes in the vehicular technology have also contributed to controlling emissions especially in case of auto-rickshaws and motorized two-wheelers, which changed from two-stroke to four-stroke. The rising trend of NOx along with the presence of VOCs indicates increasing tendency to form ground-level ozone and as a result, smog in the region. We predict that the current regime of vehicle technology, fuel standards, and high growth rate of private vehicles, is likely to nullify all the past emission reductions by the end of 2020s.

Experimental and geochemical evidence for derivation of the El Capitan Granite, California, by partial melting of hydrous gabbroic lower crust

USGS Publications Warehouse

Ratajeski, K.; Sisson, T.W.; Glazner, A.F.

2005-01-01

Partial melting of mafic intrusions recently emplaced into the lower crust can produce voluminous silicic magmas with isotopic ratios similar to their mafic sources. Low-temperature (825 and 850??C) partial melts synthesized at 700 MPa in biotite-hornblende gabbros from the central Sierra Nevada batholith (Sisson et al. in Contrib Mineral Petrol 148:635-661, 2005) have major-element and modeled trace-element (REE, Rb, Ba, Sr, Th, U) compositions matching those of the Cretaceous El Capitan Granite, a prominent granite and silicic granodiorite pluton in the central part of the Sierra Nevada batholith (Yosemite, CA, USA) locally mingled with coeval, isotopically similar quartz diorite through gabbro intrusions (Ratajeski et al. in Geol Soc Am Bull 113:1486-1502, 2001). These results are evidence that the El Capitan Granite, and perhaps similar intrusions in the Sierra Nevada batholith with lithospheric-mantle-like isotopic values, were extracted from LILE-enriched, hydrous (hornblende-bearing) gabbroic rocks in the Sierran lower crust. Granitic partial melts derived by this process may also be silicic end members for mixing events leading to large-volume intermediate composition Sierran plutons such as the Cretaceous Lamarck Granodiorite. Voluminous gabbroic residues of partial melting may be lost to the mantle by their conversion to garnet-pyroxene assemblages during batholithic magmatic crustal thickening. ?? Springer-Verlag 2005.

Desulfurization of dibenzothiophene (DBT) by a novel strain Lysinibacillus sphaericus DMT-7 isolated from diesel contaminated soil.

PubMed

Bahuguna, Ashutosh; Lily, Madhuri K; Munjal, Ashok; Singh, Ravindra N; Dangwal, Koushalya

2011-01-01

A new bacterial strain DMT-7 capable of selectively desulfurizing dibenzothiophene (DBT) was isolated from diesel contaminated soil. The DMT-7 was characterized and identified as Lysinibacillus sphaericus DMT-7 (NCBI GenBank Accession No. GQ496620) using 16S rDNA gene sequence analysis. The desulfurized product of DBT, 2-hydroxybiphenyl (2HBP), was identified and confirmed by high performance liquid chromatography analysis and gas chromatography-mass spectroscopy analysis respectively. The desulfurization kinetics revealed that DMT-7 started desulfurization of DBT into 2HBP after the lag phase of 24 hr, exponentially increasing the accumulation of 2HBP up to 15 days leading to approximately 60% desulfurization of the DBT. However, further growth resulted into DBT degradation. The induced culture of DMT-7 showed shorter lag phase of 6 hr and early onset of stationary phase within 10 days for desulfurization as compared to that of non-induced culture clearly indicating the inducibility of the desulfurization pathway of DMT-7. In addition, Lysinibacillus sphaericus DMT-7 also possess the ability to utilize broad range of substrates as sole source of sulfur such as benzothiophene, 3,4-benzo DBT, 4,6-dimethyl DBT, and 4,6-dibutyl DBT. Therefore, Lysinibacillus sphaericus DMT-7 could serve as model system for efficient biodesulfurization of diesel and petrol.

Origin and significance of the 2011 El Hierro xeno-pumice

NASA Astrophysics Data System (ADS)

Zaczek-Pedroza, Kirsten; Troll, Valentin R.; Deegan, Frances M.; Meade, Fiona C.; Burchardt, Steffi; Carracedo, Juan C.; Klügel, Andreas; Harris, Chris; Wiesmaier, Sebastian; Berg, Sylvia E.; Barker, Abigail K.

2014-05-01

During the first week of the 2011/2012 submarine eruption off El Hierro (Canary Islands), peculiar light-coloured pumiceous rocks (xeno-pumice) were found floating on the sea. The appearance of these rocks led to a potentially inappropriate response from the authorities, because the rocks were viewed as likely indicators of high-silica magma and possible explosive eruptive behaviour. However, the eruption remained a relatively minor and dominantly effusive event and the origin and significance of these peculiar xeno-pumice rocks for volcanic monitoring remains unresolved. Three contrasting models have been put forward, describing them as: a) recycled hydrothermally altered felsic magmatic rocks (Meletlidis et al., 2012, Geophys. Res. Lett., 39:L17302), b) sediment-contaminated high-silica magma (Sigmarsson et al., 2013, Contrib. Mineral. Petrol., 165:601-622) or c) frothy xenoliths from pre-island sedimentary strata that were melted while immersed in magma (Troll et al., 2012, Solid Earth, 3:97-110). Here, we combine the three available datasets to assess the origin of El Hierro xeno-pumice in the light of texture, mineralogy, major and trace element composition, and oxygen isotope characteristics in order to discuss their significance. We note that: 1) Sedimentary relicts occur frequently in xeno-pumice samples with occasionally observed relict bedding. 2) Vesicle sizes are extremely variable, which documents multiple degassing events. The vesicles are biggest especially close to sedimentary relicts, likely the result of a complex mix of minerals and porewaters originally present. 3) The mineral assemblage of xeno-pumice includes quartz, smectite, illite, wollastonite, jasper and mica (XRD) and is akin to marine sedimentary rocks in the region (Hoernle, 1998, J. Petrol.,39:859-880; Robertson & Stillman, 1979, J. Geol. Soc., 136:47 -60; Aparicio et al., 2006, Geol. Mag. 143:181 -193). 4) CIPW norms calculated from xeno-pumice major element compositions show the samples to be Si-oversaturated, partly corundum-normative, but with not magmatic mineral components in the norm. 5) Trace element concentrations of xeno-pumice are unlike any magmatic rocks from El Hierro and La Palma, but similar to known sedimentary rocks from the region. 6) A distinct Eu anomaly, typical for continentally derived sediment, is present in xeno-pumice but absent in El Hierro and La Palma magmatic rocks. Lastly, 7) Oxygen isotope values range from 9.1 to 11.6 o (n=6), which are elevated with respect to magmatic rocks from the Canaries (5.2 to ~ 7 o), but are characteristic for sediment derived from a mixture of continental (S- and I-type) granite sources. The combined datasets allow for a more thorough discussion on the origin of El Hierro xeno-pumice and we conclude that xeno-pumice is compositionally akin to sedimentary rocks from the region, but strikingly dissimilar to magmatic rocks from El Hierro and La Palma. We suggest a dominantly sedimentary origin for xeno-pumice. Xeno-pumice is therefore not an indicator for explosive felsic magma within volcanic plumbing systems, but a reflection of magma-crust interaction during ascent and emplacement. The occurrence of similar frothy sedimentary xenoliths in recent and historical eruptions on Lanzarote, Gran Canaria, Tenerife and La Palma make a case for xeno-pumice being a common phenomenon in the region.

On means of transport of Danish veterinarians during the last two hundred years.

PubMed

Katić, Ivan; Kristiansen, Johannes

2008-01-01

For almost 20 years the authors have been selecting and editing the material referring to the means of transport which Danish veterinarians used in the 18th, 19th and 20th century. The source material contains memoirs, advertisements from veterinary medical journals, obituaries and other sources, based on which a 210-page book in the Danish language has been published. The article presents an abridged version of this book. In Denmark, the first veterinarians rendered their services at the time when this profession had not yet established itself. They were relatively poor and very often they had to walk even 15 to 20 km per day in order to visit two or three farms, where their professional help was needed. In the first half of the 19th century, the economic situation of Danish veterinarians improved, so they could afford a horse of their own. From the second half of the 19th century, the gig, a light two-wheel vehicle drawn by one horse, was in use. At the end of the 19th century, bicycles and motor-bicycles were slowly gaining ground. The gig, however, continued to be the main means of transport, because it was cheap and safe. In the 20th century, the automobile era began, but World War I prevented the widespread use of cars due to the shortage of petrol, rubber parts and the like. After the war, automobiles came into common use both in medical and veterinary practice. Only in hard winters with much snow, horses and sledges were coming to the fore again. World War II once again created the shortage of petrol and rubber tyres, so horses and gas generators were in demand. After the war, various car models completely dominated the veterinary practice, cars with built-in shelves for medicines, instruments and other medical supplies in particular. The telephone was a great help and of service to veterinarians, because many of long trips to clients were not necessary any more, thanks to the simple communication over the phone. Veterinarians were often among the first owners of the telephone in a town or village, which can still be seen in their valid phone numbers (ending with 01, 02, etc.). Some veterinarians travelled also by train, during the war in particular. When there was much snow, some used skis. Some Danish veterinarians had to accompany exotic animals on their journey from Africa or Thailand, where planes were the main means of transport. In the 19th and 20th century, veterinarians used to accompany animals during their transport at sea, for example from South America to Danish colonies in West India (Tranquebar). After World War II, several veterinarians accompanied animals transported by ships to some of the Baltic harbours in the former USSR. In Denmark, there are many islands with numerous farms, therefore, if required, veterinarians from the continent have to be ready to go to the islands any time, day or night. In such cases boats are the primary means of transport, but planes and helicopters are also used in modern times. In Greenland, veterinary services are provided by veterinarians travelling by ships or boats, helicopters, and sometimes even dog-sledges.

Experimental Determination of Fe-Mg Interdiffusion Coefficients in Orthopyroxene Using Pulsed Laser Ablation and Nanoscale Thin Films

NASA Astrophysics Data System (ADS)

Ter Heege, J. H.; Dohmen, R.; Becker, H.; Chakraborty, S.

2006-12-01

Fe-Mg interdiffusion in silicate minerals is of interest in petrological studies for determining the closure temperature of geothermometers and for determining cooling rates from compositional profiles. It is also relevant for studies of the physical properties of silicates, such as rheology or electrical conductivity, because knowledge of its dependence on oxygen fugacity can aid in the understanding of point defect chemistry. Compositionally zoned orthopyroxenes are common in meteorites, mantle rocks, lower crustal rocks and a variety of plutonic and volcanic igneous rocks. However, experimental difficulties have precluded direct determination of Fe-Mg diffusion rates in orthopyroxenes so far and the available information comes from (1) Mg tracer diffusion coefficients obtained from isotope tracer studies using enriched ^{25}MgO films [1], (2) calculations of interdiffusion rates based on the (diffusion-controlled) order-disorder kinetics measured in orthopyroxene [2], and (3) indirect estimates from the comparison of diffusion widths in coexisting garnets and olivines, in which Fe-Mg diffusion rates are relatively well known [e.g., 3]. We have directly measured Fe-Mg interdiffusion coefficients parallel to the [001] direction in two natural orthopyroxene single crystals (approximately En95Fs5 and En90Fs10) using diffusion couples consisting of an olivine thin film (Fo30Fa70, typically 20 - 50 nm thick) deposited under vacuum on pre-heated, polished and oriented pyroxene single crystals using a pulsed laser ablation deposition technique. Samples were annealed for 4 - 337 hours at 800 - 1100 °C under atmospheric pressure in a continuous flow of CO + CO2 to control the oxygen fugacity between 10-16 and 10^{-12} bar within the stability field of pyroxene. Film thickness and compositional profiles were measured using Rutherford backscattering Spectroscopy (RBS) on reference and annealed samples, and Fe concentration depth profiles were extracted from the RBS spectra and fitted numerically. At an oxygen fugacity of 10-16 bar, Fe-Mg interdiffusion coefficients in the Fs richer orthopyroxene vary between 4.10^{-22} m2/s and 2.10^{-20} m2/s for temperatures between 800 and 1000°C. Diffusion coefficients decrease by a factor of ~ 4 with decreasing oxygen fugacity between 10^{-12} and 10-16 bar at 1000 °C. Comparison of our data with other Fe-Mg diffusion data shows that these diffusion coefficients are (1) similar to Mg tracer diffusion coefficients measured in orthopyroxene at somewhat more reducing (e.g. fO2 = 10-16 to 10^{-19} bar) conditions at the same temperatures [1], (2) similar to Mg tracer diffusion in garnets measured at higher pressures of 10 kbar at an oxygen fugacity corresponding to the C-O equilibrium in graphite present systems [4], and (3) slower than Fe-Mg diffusion rates in olivine by a factor of ~10 at the same oxygen fugacities [5]. Further experiments to quantify the dependence on composition, temperature and oxygen fugacity are in progress. References: [1] Schwandt et al. (1998), Contr. Mineral. Petrol. 130: 390-396; [2] Ganguly and Tazzoli (1994), Am. Mineral. 79: 930-937; [3] Smith and Barron (1991), Am. Mineral. 76: 1950-1963; [4] Ganguly et al. (1998), Contr. Mineral. Petrol. 131: 171-180; [5] Chakraborty (1997), J. Geoph. Res. 102: 12317-12331.

Sediment dynamics and the changing nature of the subduction component beneath the Kurile volcanic Arc

NASA Astrophysics Data System (ADS)

Dreyer, B.; Morris, J.; Tera, F.; Gill, J.

2006-12-01

Strong slab signatures in the lavas of the of the Kurile volcanic arc and their systematic changes across this unusually wide (~120-200km above the downgoing slab) arc provide excellent leverage for investigating the changing nature of subduction components and mixing processes across volcanic arcs. Results of new and published geochemical transects of the Kurile arc indicate a waning fluid subduction component across the arc (Bailey et al., Contrib. Mineral. Petrol., 1987; Zhuralev et al., Chem. Geol., 1987; Ryan et al., Science, 1995; Noll, et al., Geochimica et Cosmochimica Acta, 1996; Ishikawa and Tera, Earth Planet. Sci. Lett., 1997; Morris and Ryan, Treatise on Geochemistry, 2003); little geochemical change is observed along the arc. Boron, Sb, As, Pb, Cs, Ba, and Be, are progressively distilled from the slab in approximately decreasing efficiency. When the effects of decreasing degree of partial melting towards the rear-arc are minimized, Cs, Ba, and Be do not return to Pacific MORB values, indicating that they are still being added to the mantle wedge beneath the rear-arc. Despite the longer transit times, and hence additional decay of cosmogenic 10Be (t1/2=1.5Ma), 10Be/9Be ratios in the rear arc are frequently greater than or comparable to those measured at the front and requires (young, <10Ma) sediment contribution across the width of the arc, which likely reflects a greater proportion of sediment Be in rear-arc lavas, possibly as a melt or supercritical fluid (Johnson and Plank, G3, 1999). To characterize the incoming sediment and clarify the sediment dynamics beneath the Kurile arc and, new trace element, radiogenic isotope, and 10Be concentration data have been measured for a 250 meter section of marine sediments from ODP Site 1179 ~550 km outboard of the trench; these data are integrated with those of the Kurile arc lavas. Initial calculations suggest a maximum 10Be inventory of ~1.5x1013 atoms/cm2 in the incoming sediment column, which translates to a flux to the point beneath the volcanic front of ~3.4x10^{24} atoms/km-arc-Myr (corrected for additional decay during subduction). The input values will be refined with data from samples closer to the trench, but assuming magma production rates similar to other NW Pacific island arcs (30-60 km3/km-arc-Myr; Dimalanta et al., Earth Planet. Sci. Lett., 2002), a reasonable estimate for the upper limit for the 10Be recycling efficiency (ratio of 10Be flux in / 10Be flux out) is 12-24%. This range overlaps estimates for other NW Pacific island arcs (Morris et al., Rev. in Mineral. and Geochem., 2002; Morris and Ryan, Treatise on Geochemistry, 2003), with the exception of the adjacent Kamchatkan arc, which has no 10Be enrichment and has been considered an endmember for little or no sediment involvement in arc lavas (Kersting and Arculus, Earth Planet. Sci. Lett., 1995; Turner et al., Contrib. Mineral. Petrol., 1998). Recent work details the involvement of slab components in arc lavas by integrating fluid- and melt-sensitive geochemical tracers to map the transition across the arc, which may place constraints on surface temperatures of this old, cold Pacific slab.

Abnormal Eu behavior at formation of H2O- and Cl-bearing fluids during degassing of granite magmas

NASA Astrophysics Data System (ADS)

Lukanin, Oleg

2010-05-01

One of the important features of REE behavior in the process of decompression degassing of granite melts is the presence of europium anomalies in REE spectrum of forming fluid phase. Negative Eu anomaly in REE spectrum of fluids enriched by chlorine that were formed under high pressures at early stages of degassing relative to REE spectrum of granite melts may take place. Negative Eu anomaly in fluid is replaced by positive one with pressure decrease and decline of Cl concentration in fluid [1, 2]. Observable unique features of europium redistribution between fluid and melt find an explanation in such a fact that Eu in contrast to the other REE under oxidation-reduction conditions, being typical for magmatic process, is present in acidic silica-alumina melts in two valency forms Eu3+ and Eu2+ whereas the dominant form for the other REE in such a melts is (REE)3+ [3, 4]. From the analysis of melt-fluid exchange reactions with participation of two valency forms of europium Eu3+ and Eu2+ follows that the total distribution coefficient of Eu between fluid and melt D(Eu)f-m is equal as a first approximation to [5, 6]: D(Eu)f-m = a1α [C(Cl)f]3 + a2 (1 - α)[C(Cl)f]2, where C(Cl)f - the concentration of Cl in fluid, α = Eu3+/(Eu3+ + Eu2+), i.e. fraction of Eu3+ from the general amount of europium in the melt, and, a1anda2- constants that can be approximately estimated from empirical data upon Eu fluid/melt distribution. The equation given allows to estimate the influence of oxidizing condition of europium on sign and size of Eu anomaly, which is expressed by Eu/Eu# ratio, where Eu is real concentration of europium in fluid being in equilibrium with melt with constant Eu3+/(Eu3+ + Eu2+) ratio, and Eu# is possible "virtual" concentration of europium that could be in the same fluid provided that all europium as other REE as well were exclusively present in trivalent form. The sign and size of Eu anomaly in fluid depends upon Cl concentration in fluid and Eu3+/Eu2+ ratio in melt. The abnormal behavior of Eu shows itself the stronger, the lower fO2and, accordingly, the more fraction of Eu2+is present in melt. The work is supported of the Geosciences Department of the Russian Academy of Science (the program 2- 2010) and RFBR (grant 08-05-00022). References [1] Reed M.J., Candela Ph.A., Piccoli Ph.M. Contrib. Mineral. Petrol. 2000. V. 140. P. 251-262. [2] Lukanin O.A., Dernov-Pegarev V.F. Vestnik Otd. Nauk Zemle RAN, No 1(25)'2007 URL: http://www.scgis.ru/russian/cp1251/h_dgggms/1-2007/informbul-1_2007/term-30e.pdf [3] Drake M.J. Geochim. Cosmochim. Acta. 1975. V. 39. P. 55-64. [4] Wilke M. Behrens H. Contrib. Mineral. Petrol. 1999. V. 137. P. 102-114. [5] Lukanin O.A. Vestnik Otd. Nauk o Zemle RAN, No 1(26)'2008. URL: http://www.scgis.ru/russian/cp1251/h_dgggms/1-2008/informbul-1_2008/magm-20e.pdf [6] Lukanin O.A., Dernov-Pegarev V.F. Geochemistry International, 2010 (in press)

Chemical exposure and respiratory health of children in an industrial setting.

PubMed

McCarty, Kathleen M; Cleveland, Rebecca J; Franklin, Peter; Sly, Peter D

2014-01-01

Parental exposures to chemicals, and the interplay between chemical exposures in utero and in infancy leading to respiratory disease in childhood, are not yet fully understood. In this study we investigated the impact of chemical exposures to the parent in occupational settings and to the child in the home and children's respiratory health. A cross-sectional study of lung function and respiratory health was conducted in primary school children in the Kwinana industrial area, south of Perth, Western Australia. Respiratory health was assessed using a standardized questionnaire and lung function was measured using the forced oscillation technique before and after inhaling 200 μg of salbutamol. Univariate logistic regression models were used to explore the relationship between the child's respiratory health (asthma, lung function, bronchodilator response) and exposures to ceramics, dry cleaning fluid, electroplating fluid, glues, leather, fabrics, dyes, insecticides, plastics, metal cleaning fluid, petrol, paint, photochemicals, electric wiring, machining, welding, X-rays, cleaning products, nail products, and "other exposures". The impact of cigarette smoking in the home and family history on respiratory health were also investigated. No associations were found between parental occupational exposures or child's exposures in the home and respiratory health. Significant associations were observed between current smoking in the home and cigarette exposure in the first year of life and poor respiratory health in the children. We found no strong evidence of main effects of occupational exposures in impairing the respiratory health of primary school-aged children.

Exploring Best Practice Skills to Predict Uncertainties in Venture Capital Investment Decision-Making

NASA Astrophysics Data System (ADS)

Blum, David Arthur

Algae biodiesel is the sole sustainable and abundant transportation fuel source that can replace petrol diesel use; however, high competition and economic uncertainties exist, influencing independent venture capital decision making. Technology, market, management, and government action uncertainties influence competition and economic uncertainties in the venture capital industry. The purpose of this qualitative case study was to identify the best practice skills at IVC firms to predict uncertainty between early and late funding stages. The basis of the study was real options theory, a framework used to evaluate and understand the economic and competition uncertainties inherent in natural resource investment and energy derived from plant-based oils. Data were collected from interviews of 24 venture capital partners based in the United States who invest in algae and other renewable energy solutions. Data were analyzed by coding and theme development interwoven with the conceptual framework. Eight themes emerged: (a) expected returns model, (b) due diligence, (c) invest in specific sectors, (d) reduced uncertainty-late stage, (e) coopetition, (f) portfolio firm relationships, (g) differentiation strategy, and (h) modeling uncertainty and best practice. The most noteworthy finding was that predicting uncertainty at the early stage was impractical; at the expansion and late funding stages, however, predicting uncertainty was possible. The implications of these findings will affect social change by providing independent venture capitalists with best practice skills to increase successful exits, lessen uncertainty, and encourage increased funding of renewable energy firms, contributing to cleaner and healthier communities throughout the United States..

Fractionation products of basaltic komatiite magmas at lower crustal pressures: implications for genesis of silicic magmas in the Archean

NASA Astrophysics Data System (ADS)

Mandler, B. E.; Grove, T. L.

2015-12-01

Hypotheses for the origin of crustal silicic magmas include both partial melting of basalts and fractional crystallization of mantle-derived melts[1]. Both are recognized as important processes in modern environments. When it comes to Archean rocks, however, partial melting hypotheses dominate the literature. Tonalite-trondhjemite-granodiorite (TTG)-type silicic magmas, ubiquitous in the Archean, are widely thought to be produced by partial melting of subducted, delaminated or otherwise deeply buried hydrated basalts[2]. The potential for a fractional crystallization origin for TTG-type magmas remains largely unexplored. To rectify this asymmetry in approaches to modern vs. ancient rocks, we have performed experiments at high pressures and temperatures to closely simulate fractional crystallization of a basaltic komatiite magma in the lowermost crust. These represent the first experimental determinations of the fractionation products of komatiite-type magmas at elevated pressures. The aim is to test the possibility of a genetic link between basaltic komatiites and TTGs, which are both magmas found predominantly in Archean terranes and less so in modern environments. We will present the 12-kbar fractionation paths of both Al-depleted and Al-undepleted basaltic komatiite magmas, and discuss their implications for the relative importance of magmatic fractionation vs. partial melting in producing more evolved, silicic magmas in the Archean. [1] Annen et al., J. Petrol., 47, 505-539, 2006. [2] Moyen J-F. & Martin H., Lithos, 148, 312-336, 2012.

The Public Acceptance of Biofuels and Bioethanol from Straw- how does this affect Geoscience

NASA Astrophysics Data System (ADS)

Jäger, Alexander; Ortner, Tina; Kahr, Heike

2015-04-01

The Public Acceptance of Biofuels and Bioethanol from Straw- how does this affect Geoscience The successful use of bioethanol as a fuel requires its widespread acceptance by consumers. Due to the planned introduction of a 10 per cent proportion of bioethanol in petrol in Austria, the University of Applied Sciences Upper Austria carried out a representative opinion poll to collect information on the population's acceptance of biofuels. Based on this survey, interviews with important stakeholders were held to discuss the results and collect recommendations on how to increase the information level and acceptance. The results indicate that there is a lack of interest and information about biofuels, especially among young people and women. First generation bioethanol is strongly associated with the waste of food resources, but the acceptance of the second generation, produced from agricultural remnants like straw from wheat or corn, is considerably higher. The interviewees see more transparent, objective and less technical information about biofuels as an essential way to raise the information level and acceptance rate. As the production of bioethanol from straw is now economically feasible, there is one major scientific question to answer: In which way does the withdrawal of straw from the fields affect the formation of humus and, therefore, the quality of the soil? An interdisciplinary approach of researchers in the fields of bioethanol production, geoscience and agriculture in combination with political decision makers are required to make the technologies of renewable bioenergy acceptable to the population.

Lead tolerance in plants: strategies for phytoremediation.

PubMed

Gupta, D K; Huang, H G; Corpas, F J

2013-04-01

Lead (Pb) is naturally occurring element whose distribution in the environment occurs because of its extensive use in paints, petrol, explosives, sludge, and industrial wastes. In plants, Pb uptake and translocation occurs, causing toxic effects resulting in decrease of biomass production. Commonly plants may prevent the toxic effect of heavy metals by induction of various celular mechanisms such as adsorption to the cell wall, compartmentation in vacuoles, enhancement of the active efflux, or induction of higher levels of metal chelates like a protein complex (metallothioneins and phytochelatins), organic (citrates), and inorganic (sulphides) complexes. Phyotochelains (PC) are synthesized from glutathione (GSH) and such synthesis is due to transpeptidation of γ-glutamyl cysteinyl dipeptides from GSH by the action of a constitutively present enzyme, PC synthase. Phytochelatin binds to Pb ions leading to sequestration of Pb ions in plants and thus serves as an important component of the detoxification mechanism in plants. At cellular level, Pb induces accumulation of reactive oxygen species (ROS), as a result of imbalanced ROS production and ROS scavenging processes by imposing oxidative stress. ROS include superoxide radical (O2(.-)), hydrogen peroxide (H2O2) and hydroxyl radical ((·)OH), which are necessary for the correct functioning of plants; however, in excess they caused damage to biomolecules, such as membrane lipids, proteins, and nucleic acids among others. To limit the detrimental impact of Pb, efficient strategies like phytoremediation are required. In this review, it will discuss recent advancement and potential application of plants for lead removal from the environment.

Factors associated with elevated blood lead concentrations in children in Karachi, Pakistan.

PubMed Central

Rahbar, Mohammad Hossein; White, Franklin; Agboatwalla, Mubina; Hozhabri, Siroos; Luby, Stephen

2002-01-01

OBJECTIVES: To confirm whether blood lead concentrations in Karachi were as high as reported in 1989 and to identify which types of exposure to lead contribute most to elevated blood lead concentrations in children in Karachi. METHODS: A total of 430 children aged 36-60 months were selected through a geographically stratified design from the city centre, two suburbs, a rural community and an island situated within the harbour at Karachi. Blood samples were collected from children and a pretested questionnaire was administered to assess the effect of various types of exposure. Cooked food, drinking-water and house dust samples were collected from households. FINDINGS: About 80% of children had blood lead concentrations 10 g/dl, with an overall mean of 15.6 g/dl. At the 5% level of significance, houses nearer to the main intersection in the city centre, application of surma to children's eyes, father's exposure to lead at workplace, parents' illiteracy and child's habit of hand- to-mouth activity were among variables associated with elevated lead concentrations in blood. CONCLUSION: These findings are of public health concern, as most children in Karachi are likely to suffer some degree of intellectual impairment as a result of environmental lead exposure. We believe that there is enough evidence of the continuing problem of lead in petrol to prompt the petroleum industry to take action. The evidence also shows the need for appropriate interventions in reducing the burden due to other factors associated with this toxic element. PMID:12471396

Substance misuse in Aboriginal Australians.

PubMed

Gracey, M

1998-01-01

Australia's Aborigines lived in isolation from the rest of humanity as successful hunter-gatherers for tens of thousands of years. That isolation ended abruptly with British colonization in the late 18th century and was followed by a traumatic 200 years for Aborigines who are now seriously disadvantaged, socio-economically and in terms of their health standards. It has often been assumed that the Aborigines had no access to psychotropic substances before permanent European contact but several pieces of evidence dispute this view. The history of Aboriginal contact with and usage of intoxicating substances, including alcohol, is extremely complex and affected by a maze of restrictive government policies. These interact with a wide range of other Federal and State policies which have changed rapidly since the late 1960s when Aborigines were first granted the franchise; access to unrestricted drinking followed soon afterwards. Today Aborigines suffer disproportionately to other Australians from the physical and social consequences of excess alcohol consumption, tobacco usage, petrol and other solvent sniffing, usage of marijuana, amphetamines, cocaine and heroin, as well as other drugs. The Aboriginal population is dispersed in cities, towns, fringe settlements, rural and remote areas over this vast continent and there are different patterns of drug usage from place to place. This review attempts to synthesize some of this information in order to give an overview to the history, background, current status of substance misuse by Aborigines as well as some strategies being used to try to overcome this serious problem.

Vulnerability of settlements around Mt. Cameroon volcano, Cameroon

NASA Astrophysics Data System (ADS)

Zogning, Appolinaire; Spinetti, Claudia; Ngouanet, Chretien; Tchoudam, David; Kouokam, Emmanuel; Thierry, Pierre; Bignami, Christian; Fabrizia Buongiorno, Maria; Ilaria Pannaccione Apa, Maria

2010-05-01

Located at the bottom of the Gulf of Guinea, Cameroon is exposed to a large variety of natural hazards, including volcanism. Most of the hazard are concentrated around the active volcano Mt. Cameroon which combines effusive and explosive types of activity. The threatened stakes are numerous and different exposed: people, settlements, industrial plantations, petrol refinery and many other factories and infrastructures. Until 2005, no risk management plans has been available. In 2006, the French Embassy in Cameroon, within the framework of a financial convention between Cameroon and France, put in place the GRINP (Management of Natural Risks and Civil Protection) project whose objective was to reinforce the capacity of Cameroon's civil protection department and thus, contribute to the improvement of the security of the population faced with catastrophes. The objective was to realize a Risk Prevention Plan at a local council scale, and taking into consideration the specific natural risks of each zone. The general objective of the RPP was to clearly draw land use maps for risks zones, showing the overlay of stakes with risk of different intensities. In 2008 European Commission funded the Mia-Vita project (Mitigating and Assessing Volcanic Impacts on Terrain and human Activities). The aim of the project is to improve the crisis management capabilities based on monitoring and early warning systems and secure communications; reduction of people's vulnerability and development of recovering capabilities after an event occurs for both local communities and ecological systems. Keyword: natural hazards, Mt. Cameroon, vulnerability, risk prevention plan

What factors play a role in preventing self-immolation? Results from a case-control study in Iran

PubMed Central

Karim, Hosein; Schwebel, David C.; Bazargan-Hejazi, Shahrzad; Mohammadi, Reza; Choubsaz, Mansour; Heidari Zadie, Zahra; Ahmadi, Alireza

2015-01-01

Abstract: Background: To investigate factors related to prevention of self-immolation in west of Iran. Methods: In a case-control study, 30 consecutive cases of deliberate self-inflicted burns admitted to the regional burn center (Imam Khomeini hospital in Kermanshah province, Iran) were compared with controls selected from the community and matched by sex, age, district-county of residence, and rural vs urban living environment. The following characteristics relevant to preventing self-immolation were collected from all cases and controls: main domestic fuel used in the household, awareness about complications of burn injuries, and use of counseling services. Results: Descriptive analyses revealed that kerosene was the main domestic fuel in the household for 83% of cases. Not surprisingly, the main means of self-immolation in 93% of the patients was kerosene, with other fuels such as petrol and domestic gas used in remaining cases. The majority of cases and controls were aware of the potential complications of burn injuries. Use of counseling services was more common in controls. Conclusions: All three aspects of preventing self-immolation – having kerosene and other fuels in the home, being aware of the complications of burn injuries, and using counseling services were present in both the cases and controls. This suggests a large portion of residents in rural Iran are potential self-immolation victims. Increasing preventive strategies may reduce risk of suicide by self-immolation. PMID:26081518

New family of biosensors for monitoring BTX in aquatic and edaphic environments.

PubMed

Hernández-Sánchez, Verónica; Molina, Lázaro; Ramos, Juan Luis; Segura, Ana

2016-11-01

Benzene, toluene, ethylbenzene and xylenes (BTEX) contamination is a serious threat to public health and the environment, and therefore, there is an urgent need to detect its presence in nature. The use of whole-cell reporters is an efficient, easy-to-use and low-cost approach to detect and follow contaminants outside specialized laboratories; this is especially important in oil spills that are frequent in marine environments. The aim of this study is the construction of a bioreporter system and its comparison and validation for the specific detection of monocyclic aromatic hydrocarbons in different host bacteria and environmental samples. Our bioreporter system is based on the two component regulatory system TodS-TodT of P. putida DOT-T1E, and the P todX promoter fused to the GFP protein as the reporter protein. For the construction of different biosensors, this bioreporter was transferred into three different bacterial strains isolated from three different environments, and their performance was measured. Validation of the biosensors on water samples spiked with petrol, diesel and crude oil on contaminated waters from oil spills and on contaminated soils demonstrated that they can be used in mapping and monitoring some BTEX compounds (specifically benzene, toluene and two xylene isomers). Validation of biosensors is an important issue for the integration of these devices into pollution-control programmes. © 2016 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

Identifying sources of Pb pollution in urban soils by means of MC-ICP-MS and TOF-SIMS.

PubMed

Rodríguez-Seijo, Andrés; Arenas-Lago, Daniel; Andrade, María Luisa; Vega, Flora A

2015-05-01

Lead pollution was evaluated in 17 urban soils from parks and gardens in the city of Vigo (NW Spain). The Pb isotope ratios ((207)Pb/(206)Pb, (208)Pb/(204)Pb, (206)Pb/(204)Pb and (208)Pb/(206)Pb) were determined after being measured by MC-ICP-MS. The association of the isotopes ((204)Pb, (206)Pb, (207)Pb and (208)Pb) with the different components of the soil was studied using TOF-SIMS. The isotopic ranges obtained for the samples were between 1.116 and 1.203 ((206)Pb/(207)Pb), 2.044-2.143 ((208)Pb/(206)Pb), 37.206-38.608 ((208)Pb/(204)Pb), 15.5482-15.6569 ((207)Pb/(204)Pb) and 17.357-18.826 ((206)Pb/(204)Pb). The application of the three-end-member model indicates that the Pb derived from petrol is the main source of Pb in the soils (43.51% on average), followed by natural or geogenic Pb (39.12%) and industrial emissions (17.37%). The emissions derived from coal combustion do not appear to influence the content of Pb in the soil. TOF-SIMS images show that the Pb mainly interacts with organic matter. This technique contributes to the understanding of the association of anthropogenic Pb with the components of the soil, as well as the particle size of these associations, thus allowing the possible sources of Pb to be identified.

Process of optimization of district heat production by utilizing waste energy from metallurgical processes

NASA Astrophysics Data System (ADS)

Konovšek, Damjan; Fužir, Miran; Slatinek, Matic; Šepul, Tanja; Plesnik, Kristijan; Lečnik, Samo

2017-07-01

In a consortium with SIJ (Slovenian Steel Group), Metal Ravne, the local community of Ravne na Koro\\vskem and the public research Institut Jožef Stefan, with its registered office in Slovenia, Petrol Energetika, d.o.o. set up a technical and technological platform of an innovative energy case for a transition of steel industry into circular economy with a complete energy solution called »Utilization of Waste Heat from Metallurgical Processes for District Heating of Ravne na Koro\\vskem. This is the first such project designed for a useful utilization of waste heat in steel industry which uses modern technology and innovative system solutions for an integration of a smart, efficient and sustainable heating and cooling system and which shows a growth potential. This will allow the industry and cities to make energy savings, to improve the quality of air and to increase the benefits for the society we live in. On the basis of circular economy, we designed a target-oriented co-operation of economy, local community and public research institute to produce new business models where end consumers are put into the centre. This innovation opens the door for steel industry and local community to a joint aim that is a transition into efficient low-carbon energy systems which are based on involvement of natural local conditions, renewable energy sources, the use of waste heat and with respect for the principles of sustainable development.

Estimating the burden of disease attributable to lead exposure in South Africa in 2000.

PubMed

Norman, Rosana; Mathee, Angela; Barnes, Brendon; van der Merwe, Lize; Bradshaw, Debbie

2007-08-01

To estimate the burden of disease attributable to lead exposure in South Africa in 2000. World Health Organization comparative risk assessment (CRA) methodology was followed. Recent community studies were used to derive mean blood lead concentrations in adults and children in urban and rural areas. Population-attributable fractions were calculated and applied to revised burden of disease estimates for the relevant disease categories for South Africa in the year 2000. Monte Carlo simulation-modelling techniques were used for the uncertainty analysis. South Africa. Children under 5 and adults 30 years and older. Cardiovascular mortality and disability-adjusted life years (DALYs) in adults 30 years and older and mild mental disability DALYs in children under 5 years. Lead exposure was estimated to cause 1,428 deaths (95% uncertainty interval 1,086-1,772) or 0.27% (95% uncertainty interval: 0.21 - 0.34%) of all deaths in South Africa in 2000. Burden of disease attributed to lead exposure was dominated by mild mental disability in young children, accounting for 75% of the total 58,939 (95% uncertainty interval 55,413 - 62,500) attributable DALYs. Cardiovascular disease in adults accounted for the remainder of the burden. Even with the phasing out of leaded petrol, exposure to lead from its ongoing addition to paint, para-occupational exposure and its use in backyard 'cottage industries' will continue to be an important public health hazard in South Africa for decades. Young children, especially those from disadvantaged communities, remain particularly vulnerable to lead exposure and poisoning.

Oxygen fugacity and piston cylinder capsule assemblies

NASA Astrophysics Data System (ADS)

Jakobsson, S.

2011-12-01

A double capsule assembly designed to control oxygen fugacity in piston cylinder experiments has been tested at 1200 °C and 10 kbar. The assembly consists of an outer Pt-capsule containing a solid buffer (Ni-NiO or Co-CoO plus H2O) and an inner AuPd-capsule containing the sample, H2O and a Pt-wire. To prevent direct contact with the buffer phases the AuPd-capsule is embedded in finely ground Al2O3 along with some coarser, fractured Al2O3 facilitating fluid inclusion formation. No water loss is observed in the sample even after 48 hrs but a slight increase in water content is observed in longer duration runs due to oxygen and hydrogen diffusion into the AuPd-capsule. Carbon from the furnace also diffuses through the outer Pt-capsule but reacts with H2O in the outer capsule to form CO2 and never reaches the inner capsule. Oxygen fugacity of runs in equilibrium with the Ni-NiO and Co-CoO buffers was measured by analyzing the Fe content of the Pt-wire in the sample1 and by analyzing Fe dissolved in the AuPd capsule2. The second method gives values that are in good agreement with established buffer whereas results from the first method are one half to one log units higher than the established values. References 1. E. Medard, C. A. McCammon, J. A. Barr, T. L. Grove, Am. Mineral. 93, 1838 (2008). 2. J. Barr, T. Grove, Contrib. Mineral. Petrol. 160, 631 (2010)

Extrusion foaming of thermoplastic cellulose acetate from renewable resources using a two-component physical blowing agent system

NASA Astrophysics Data System (ADS)

Hopmann, Ch.; Windeck, C.; Hendriks, S.; Zepnik, S.; Wodke, T.

2014-05-01

Thermoplastic cellulose acetate (CA) is a bio-based polymer with optical, mechanical and thermal properties comparable to those of polystyrene (PS). The substitution of the predominant petrol-based PS in applications like foamed food trays can lead to a more sustainable economic practice. However, CA is also suitable for more durable applications as the biodegradability rate can be controlled by adjusting the degree of substitutions. The extrusion foaming of CA still has to overcome certain challenges. CA is highly hydrophilic and can suffer from hydrolytic degradation if not dried properly. Therefore, the influence of residual moisture on the melt viscosity is rather high. Beyond, the surface quality of foam CA sheets is below those of PS due to the particular foaming behaviour. This paper presents results of a recent study on extrusion foamed CA, using a two-component physical blowing agent system compromising HFO 1234ze as blowing agent and organic solvents as co-propellant. Samples with different co-propellants are processed on a laboratory single screw extruder at IKV. Morphology and surface topography are investigated with respect to the blowing agent composition and the die pressure. In addition, relationships between foam density, foam morphology and the propellants are analysed. The choice of the co-propellant has a significant influence on melt-strength, foaming behaviour and the possible blow-up ratio of the sheet. Furthermore, a positive influence of the co-propellant on the surface quality can be observed. In addition, the focus is laid on the effect of external contact cooling of the foamed sheets after the die exit.

Ions in motor vehicle exhaust and their dispersion near busy roads

NASA Astrophysics Data System (ADS)

Jayaratne, E. R.; Ling, X.; Morawska, L.

2010-09-01

Measurements in the exhaust plume of a petrol-driven motor car showed that molecular cluster ions of both signs were present in approximately equal amounts. The emission rate increased sharply with engine speed while the charge symmetry remained unchanged. Measurements at the kerbside of nine motorways and five city roads showed that the mean total cluster ion concentration near city roads (603 cm -3) was about one-half of that near motorways (1211 cm -3) and about twice as high as that in the urban background (269 cm -3). Both positive and negative ion concentrations near a motorway showed a significant linear increase with traffic density ( R2 = 0.3 at p < 0.05) and correlated well with each other in real time ( R2 = 0.87 at p < 0.01). Heavy duty diesel vehicles comprised the main source of ions near busy roads. Measurements were conducted as a function of downwind distance from two motorways carrying around 120-150 vehicles per minute. Total traffic-related cluster ion concentrations decreased rapidly with distance, falling by one-half from the closest approach of 2 m to 5 m of the kerb. Measured concentrations decreased to background at about 15 m from the kerb when the wind speed was 1.3 m s -1, this distance being greater at higher wind speed. The number and net charge concentrations of aerosol particles were also measured. Unlike particles that were carried downwind to distances of a few hundred metres, cluster ions emitted by motor vehicles were not present at more than a few tens of metres from the road.

A longitudinal study of externally visible cigarette advertising on retail storefronts in Massachusetts before and after the Master Settlement Agreement.

PubMed

Celebucki, Carolyn C; Diskin, K

2002-06-01

To assess the effect of the Master Settlement Agreement (MSA) on the amount of cigarette advertisements visible from outside of over-the-counter tobacco retailers, for five specific premium brands and an "all other" category, for five types of establishments, and in three areas (windows/doors, building/other detached areas, and sidewalks); to assess the relation of total exterior retail cigarette advertising to illegal sales to youth. Observations were conducted on the number of cigarette advertisements visible from outside tobacco retail establishments in a paired convenience sample (n = 556) in Massachusetts before and after the MSA. Archival databases containing information on merchant compliance with age related sales laws during the time period were used to assess the relation of total cigarette advertising with sales to underage youth. Paired sample t tests assessed planned comparisons pre- to post-MSA; Spearman's rho tested associations for dichotomous variables. Significant post-ban increases were observed in the prevalence of exterior cigarette advertising on gas (petrol) stations and gas mini/marts (gasoline retailers) buildings, windows, and doors. Significant declines were observed on windows of liquor stores. Winston advertising declined overall, while advertisements of the "all other" brand category increased. Correlations between advertising and illegal sales, while modest, were significant. These pre- to post-MSA increases suggest the tobacco industry may be shifting expenditures selectively from billboard advertising to retailer exteriors more favoured by youth. Greater amount of cigarette advertising visible from outside over-the-counter tobacco retailers is associated with greater cigarette sales to minors.

An estimation of traffic related CO2 emissions from motor vehicles in the capital city of, Iran

PubMed Central

2012-01-01

Vehicle exhaust is a major source of anthropogenic carbon dioxide (CO2) in metropolitan cities. Popular community mode (buses and taxies) and about 2.4 million private cars are the main emission sources of air pollution in Tehran. A case survey has conducted to measure CO2 in four popular vehicles, bus, taxi, private car and motorcycle, which moved in the city with respectively 7800, 82358, 560000 and 2.4 million per day in 2012. Results indicated that the contribution of CO2 emissions increased in the following order: private car, motorcycle, bus and taxi. The overall average for the contribution of CO2 emissions in the private car, motorcycle, bus, and taxi were 26372, 1648, 1433 and 374 tons per day, respectively. Our results also showed that the urban transport operation consume an estimated 178 and 4224 million liter diesel and petrol per year, respectively, that have released about 10 million tons of CO2. The average contribution of CO2 emissions of private cars in Tehran was higher (88%) than other vehicles. It was concluded that high volume of traffic, transport consumption of fossil fuels and shortage of adequate public transport system are responsible for the high CO2 level in environment in Tehran. Thus, it is to be expected that CO2 as a greenhouse gas has risen in Tehran more than ever in the following years and this would be a matter of concern for the authorities to have a comprehensive plan to mitigate this phenomena. PMID:23369252

A review of programs that targeted environmental determinants of Aboriginal and Torres Strait Islander health.

PubMed

Johnston, Leah; Doyle, Joyce; Morgan, Bec; Atkinson-Briggs, Sharon; Firebrace, Bradley; Marika, Mayatili; Reilly, Rachel; Cargo, Margaret; Riley, Therese; Rowley, Kevin

2013-08-09

Effective interventions to improve population and individual health require environmental change as well as strategies that target individual behaviours and clinical factors. This is the basis of implementing an ecological approach to health programs and health promotion. For Aboriginal People and Torres Strait Islanders, colonisation has made the physical and social environment particularly detrimental for health. We conducted a literature review to identify Aboriginal health interventions that targeted environmental determinants of health, identifying 21 different health programs. Program activities that targeted environmental determinants of health included: Caring for Country; changes to food supply and/or policy; infrastructure for physical activity; housing construction and maintenance; anti-smoking policies; increased workforce capacity; continuous quality improvement of clinical systems; petrol substitution; and income management. Targets were categorised according to Miller's Living Systems Theory. Researchers using an Indigenous community based perspective more often identified interpersonal and community-level targets than were identified using a Western academic perspective. Although there are relatively few papers describing interventions that target environmental determinants of health, many of these addressed such determinants at multiple levels, consistent to some degree with an ecological approach. Interpretation of program targets sometimes differed between academic and community-based perspectives, and was limited by the type of data reported in the journal articles, highlighting the need for local Indigenous knowledge for accurate program evaluation. While an ecological approach to Indigenous health is increasingly evident in the health research literature, the design and evaluation of such programs requires a wide breadth of expertise, including local Indigenous knowledge.

Site suitability evaluation of an old operating landfill using AHP and GIS techniques and integrated hydrogeological and geophysical surveys.

PubMed

Saatsaz, Masoud; Monsef, Iman; Rahmani, Mostafa; Ghods, Abdolreza

2018-02-16

Because of the outdated methods of common landfill selection, it is imperative to reevaluate the usage suitability. To assess the suitability of the existing waste landfill in Zanjan, Iran, we have used a combination of the analytical hierarchy process (AHP) and GIS techniques, along with fieldwork surveys. Four major criteria and 12 subcriteria were considered, and the AHP was applied to assign the relative importance weights of criteria and subcriteria to each other. Finally, a landfill suitability map was generated and ranked based on the final suitability scores. The results show that the unsuitable areas are around Zanjan, in the middle parts of the plain. By contrast, the most suitable areas are uncultivated areas, located mostly in the west, north, and south. The results also indicate that the present landfill is a highly suitable site. After desk studies, geoelectrical surveys and infiltration measurements were conducted to make the final decision. Double-ring permeability tests confirm the landfill is an acceptable site. The electrical sounding shows that the leachate plume has a width of about ~ 450 m, spreads to a depth of about ~ 55 m, and migrates towards the northeast. Considering the groundwater depth, dry climate, and a low infiltration rate of the landfill soils, it can be concluded that leachate plumes will not contaminate groundwater within this decade. The proposed method can be implemented to reevaluate the suitability of any old operating reservoir such as oil reservoirs, petrol filling stations, heavy industrial tanks, and landfills, containing liquid hazardous materials.

An estimation of traffic related CO2 emissions from motor vehicles in the capital city of, Iran.

PubMed

Kakouei, Aliakbar; Vatani, Ali; Idris, Ahmed Kamal Bin

2012-11-28

Vehicle exhaust is a major source of anthropogenic carbon dioxide (CO2) in metropolitan cities. Popular community mode (buses and taxies) and about 2.4 million private cars are the main emission sources of air pollution in Tehran. A case survey has conducted to measure CO2 in four popular vehicles, bus, taxi, private car and motorcycle, which moved in the city with respectively 7800, 82358, 560000 and 2.4 million per day in 2012. Results indicated that the contribution of CO2 emissions increased in the following order: private car, motorcycle, bus and taxi. The overall average for the contribution of CO2 emissions in the private car, motorcycle, bus, and taxi were 26372, 1648, 1433 and 374 tons per day, respectively. Our results also showed that the urban transport operation consume an estimated 178 and 4224 million liter diesel and petrol per year, respectively, that have released about 10 million tons of CO2. The average contribution of CO2 emissions of private cars in Tehran was higher (88%) than other vehicles. It was concluded that high volume of traffic, transport consumption of fossil fuels and shortage of adequate public transport system are responsible for the high CO2 level in environment in Tehran. Thus, it is to be expected that CO2 as a greenhouse gas has risen in Tehran more than ever in the following years and this would be a matter of concern for the authorities to have a comprehensive plan to mitigate this phenomena.

French academic's views on financial compensation of participants.

PubMed

Dualé, Christian; Breysse, Gaétan; Bories-Azeau, Béatrice; Cornu, Catherine

2016-07-01

Whether and how participants in biomedical research should receive financial compensation is debated. We wished to explore how this issue was perceived by French professionals, focusing on different conditions of research. We surveyed referent responders of Clinical Investigation Centres, Research Ethics Committees and hospital administrative departments for clinical research, via referent responders who completed an online questionnaire on behalf of their respective teams. Financial compensation was addressed in terms of general perception, justifications, interpretation of French law, concrete clinical situations and compensation of incurred expenses. Descriptive analyses and correlations were carried out based on scalar responses. The questionnaire was answered by 54/116 (45·6%) centres. The ethical aspects of compensation were viewed differently by Clinical Investigation Centres and Research Ethics Committees, whereas the practical aspects were viewed similarly. Agreement to compensation for patients was lower than for healthy volunteers (74·1 vs. 98·2%). The most frequently cited justifications for compensation apart from the inconveniences of research were the potential risk and the absence of medical benefit. Most of the proposed expenses incurred were to be compensated, but agreement to reimbursement of petrol bills or childcare expense was lower. Although some of the responses align with previous surveys in other countries, this information may help French professionals to harmonise their practices. We also addressed practical issues which could be studied in other European countries, for professionals and participants. Finally, the reluctance to compensate patients requires further study, taking into account welfare environment and consequences for recruitment. © 2016 Stichting European Society for Clinical Investigation Journal Foundation.

Apatite Mineral Chemistry From IOA Deposits in Northern Chile

NASA Astrophysics Data System (ADS)

Palma, G.; Barra, F.; Reich, M.; Valencia, V.; Simon, A. C.; Vervoort, J. D.

2017-12-01

The Carmen, Fresia and Mariela iron-oxide apatite (IOA) deposits of Cretaceous age, located in the Coastal Cordillera of northern Chile, comprise massive bodies of magnetite with minor apatite and actinolite crystals spatially related to diorite intrusions. In order to provide new insights on the origin of Andean IOA deposits, we provide geochemical data of apatite grains collected from these three deposits. All studied apatite grains are zoned with respect to Cl and F, and show a decoupled behaviour between fluorapatite and chlorapatite. Carmen apatite grains are mostly F-rich, whereas in Mariela apatite grains are Cl-rich. Fresia apatite grains show a variable composition between fluorapatite and chlorapatite. Carmen apatite grains show a high REE content reaching up to 7000 ppm, and both Fresia and Mariela have lower REE content (<1400 ppm). REE patterns for all analyzed apatite grains show the typical LREE enrichment relative to the HREE and pronounced negative Eu anomaly, which indicates crystallization of plagioclase in the source magmas [1]. Chlorapatite zones are characterized by high S, Na, Sr and Fe content relative to fluorapatite zones. Notably S and Na show a coupled behaviour with Cl. Conversely LREE are depleted in chlorapatite zones, which is compatible with metasomatism through dissolution-reprecipitation mechanism and formation of monazite inclusions [2]. These results indicate a magmatic origin for fluorapatite in these Andean IOA deposits followed by variable degrees of hydrothermal overprint which resulted in the formation of Cl-rich apatites.[1] Frietsch & Perdahl (1995) Ore Geology Rev. 9 489-510. [2]Harlov et al. (2005) Contrib Mineral Petrol 150: 268-286

Carbon monoxide levels measured in major commuting corridors covering different landuse and roadway microenvironments in Hong Kong

NASA Astrophysics Data System (ADS)

Chan, L. Y.; Liu, Y. M.; Lee, S. C.; Chan, C. Y.

Vehicle exhaust is the major source of pollutant in modern cities. About half of Hong Kong residents are living in suburban or rural areas. They need to traverse through tunnels, highways, urban street canyons and other road conditions in different landuse areas when they traverse to work in urban centres or new towns. Also, there is increasing traffic, especially trucks across the border between Hong Kong and mainland China via several border highways. This study helps us in assessing the exposure level of suburban and cross border commuters. Carbon monoxide (CO) is used as a tracer for traffic emission. An experimental vehicle traversing major commuting corridors were used to measure CO levels in different landuse and roadway microenvironments including tunnels and highways. The air samples were taken simultaneously at the outside and inside of a travelling vehicle. Result indicates that the pattern of fluctuation of the out-vehicle and in-vehicle CO level vary with different landuse areas. The variation pattern of in-vehicle CO level is closely related to that of out-vehicle level. The effects of the out-vehicle CO concentration on the in-vehicle CO concentration under different roadway conditions in various landuse categories are examined. There is an indication that external air pollutants penetrated into the in-vehicle compartment through car body cracks, ventilation system. From our observation, the exhaust of a nearby petrol vehicle contributed significantly to the in-vehicle CO level. The use of low standard of diesel fuel from Shenzhen in mainland China leads to higher CO level near border area.

Straw use and availability for second generation biofuels in England.

PubMed

Glithero, Neryssa J; Wilson, Paul; Ramsden, Stephen J

2013-08-01

Meeting EU targets for renewable transport fuels by 2020 will necessitate a large increase in bioenergy feedstocks. Although deployment of first generation biofuels has been the major response to meeting these targets they are subject to wide debate on their sustainability leading to the development of second generation technologies which use lignocellulosic feedstocks. Second generation biofuel can be subdivided into those from dedicated bioenergy crops (DESGB), e.g. miscanthus, or those from co-products (CPSGB) such as cereal straw. Potential supply of cereal straw as a feedstock for CPSGB's is uncertain in England due to the difficulty in obtaining data and the uncertainty in current estimates. An on-farm survey of 249 farms (Cereal, General Cropping and Mixed) in England was performed and linked with Farm Business Survey data to estimate current straw use and potential straw availability. No significant correlations between harvested grain and straw yields were found for wheat and oilseed rape and only a weak correlation was observed for barley. In England there is a potential cereal straw supply of 5.27 Mt from arable farm types; 3.82 Mt are currently used and 1.45 Mt currently chopped and incorporated. If currently chopped and incorporated cereal straw from arable farm types was converted into bioethanol, this could represent 1.5% of the UK petrol consumption by energy equivalence. The variations in regional straw yields (t ha -1 ) have a great effect on the England supply of straw and the potential amount of bioethanol that can be produced.

Stomach cancer and occupation in Sweden: 1971–89

PubMed Central

Aragones, N; Pollan, M; Gustavsson, P

2002-01-01

Objectives: To examine the relation between gastric cancer and occupation among men and women gainfully employed in 1970 in Sweden for the period 1971–89 and, more specifically, to evaluate whether any excess of incidence of gastric cancer had also occurred among the subcohort of people reporting the same occupation in 1960 and 1970. Methods: In both sexes and cohorts, relative risks adjusted for age, period of diagnosis, and geographical risk area were computed for occupational codes specified at one, two, or three level (occupational sector, occupational group, and occupation, respectively). Relative risks were calculated with all other occupations as reference and then, to take socioeconomic status into account, solely other occupations within the same occupational sector were used. Results: Among men, occupations with increased risk included miners and quarrymen, construction and metal processing workers, supporting the possible causative role of dusty environments in stomach cancer. In men, the results also provide support for increased risks among electrical and mechanical engineers, fishermen, petrol station workers, motor vehicle drivers, butchers and meat preparers, dockers, freight handlers, launderers and dry cleaners. Furthermore, it is worth noting interesting results for women, whose occupational risks have been studied less. Excess risks were found for practical nurses, cashiers, bank employees, engineering and electronic industry workers, food industry, housekeeping and cleaning workers. Due to the many occupations studied, several significant associations may be expected by chance. Conclusions: The study is explorative but provides support for the relations suggested previously between occupational exposure to dusty environments and stomach cancer, together with some new high risk occupations which should be further studied. PMID:11983848

Mobile Optical Remote Sensing Measurements of VOC's to Quantify Emissions and to Map Impact

NASA Astrophysics Data System (ADS)

Mellqvist, J.; Samuelsson, J.; Marianne, E.; Brohede, S.; Andersson, P.; Johansson, J.; Izos, O.; Polidori, A.; Pikelnaya, O.

2017-12-01

Industrial volatile organic compound (VOC) emissions may cause direct health problems and contribute significantly to ozone formation. In order to investigate how small sources contribute to the VOC concentrations in the Los Angeles metropolitan area a comprehensive emission study has been carried out on behalf of the South Coast Air Quality Management District (SCAQMD). Emission measurements of alkanes, alkenes, aromatic VOCs and methane from major sources such as refineries, oil wells, petrol stations oil depots and oil platforms were measured in an intensive campaign during the fall of 2015 using several unique optical methods, including the Solar Occultation Flux method (SOF) and tracer correlation technique based on extractive FTIR and DOAS combined with an open path multi reflection cell. In 2017 these measurements have been continued during four shorter campaigns on several of the identified hot spot emission sites. The objective has been to study the time evolution and annual variation of the emission sources and their impact on the surroundings. The latter has been carried out by mobile mapping of VOC concentrations downwind of the sources and comparison to low cost portable PID sensors. The results from the field campaigns show that the emissions from the above mentioned sources are largely underestimated in inventories with potential impact on the air quality in the Los Angeles metropolitan area. In this presentation we will describe the optical techniques and describe recent standardization work carried out in Europe and the US. In addition, results from the measurements in the LA-basin will be shown and discussed.

Origins and trends in ethane and propane in the United Kingdom from 1993 to 2012

NASA Astrophysics Data System (ADS)

Derwent, R. G.; Field, R. A.; Dumitrean, P.; Murrells, T. P.; Telling, S. P.

2017-05-01

Continuous, high frequency in situ observations of ethane and propane began in the United Kingdom in 1993 and have continued through to the present day at a range of kerbside, urban background and rural locations. Whilst other monitored C2 - C8 hydrocarbons have shown dramatic declines in concentrations by close to or over an order of magnitude, ethane and propane levels have remained at or close to their 1993 values. Urban ethane sources appear to be dominated by natural gas leakage. Background levels of ethane associated with long range transport are rising. However, natural gas leakage is not the sole source of urban propane. Oil and gas operations lead to elevated propane levels in urban centres when important refinery operations are located nearby. Weekend versus weekday average diurnal curves for ethane and propane at an urban background site in London show the importance of natural gas leakage for both ethane and propane, and road traffic sources for propane. The road traffic source of propane was tentatively identified as arising from petrol-engined motor vehicle refuelling and showed a strong downwards trend at the long-running urban background and rural sites. The natural gas leakage source of ethane and propane in the observations exhibits an upwards trend whereas that in the UK emission inventory trends downwards. Also, inventory emissions for natural gas leakage appeared to be significantly underestimated compared with the observations. In addition, the observed ethane to propane ratio found here for natural gas leakage strongly disagreed with the inventory ratio.

Organic and Inorganic Pollutant Concentrations Suggest Anthropogenic Contamination of Soils Along the Manali-Leh Highway, Northwestern Himalaya, India.

PubMed

Dasgupta, Rajarshi; Crowley, Brooke E; Barry Maynard, J

2017-05-01

Most studies on roadside soil pollution have been performed in areas where petrol is the main fuel. Very little work has been conducted in regions where diesel predominates. We collected soil samples from four sites that span a precipitation gradient along the Manali-Leh Highway in northwestern Himalaya, India. This road traverses rough terrain and most of the vehicles that travel along it are diesel-driven. At each site, we collected samples at incremental distances from the highway (0, 2, 5, 10, 20, and 150 m), and at each distance we collected samples from three depths (3, 9, and 15 cm). We assessed the concentrations of 10 heavy metals (Al, Fe, Cr, Cu, Pb, Ni, Co, Zn, V, and Ba), total sulphur, and total organic carbon (TOC) at each distance, and we measured the concentration of 16 polycyclic aromatic hydrocarbons (PAHs) at 2 m from the highway. Overall, we found that metal concentrations are low and there is no relationship between concentrations and distance from the highway, or depth within the soil profile. Sulphur concentrations, on the other hand, are high in roadside soils and there is a negative relationship between concentration and distance from the highway. PAH concentrations are low, but the proportion of different ringed species suggests that their source is anthropogenic. Correlations between TOC and the various pollutants further suggest that diesel vehicles and potentially biomass combustion are starting to affect the roadside environment in remote northwestern India. We suggest that pollutant concentrations be regularly monitored.

Estimation of vehicular emissions using dynamic emission factors: A case study of Delhi, India

NASA Astrophysics Data System (ADS)

Mishra, Dhirendra; Goyal, P.

2014-12-01

The estimation of vehicular emissions depends mainly on the values of emission factors, which are used for the development of a comprehensive emission inventory of vehicles. In this study the variations of emission factors as well as the emission rates have been studied in Delhi. The implementation of compressed natural gas (CNG), in the diesel and petrol, public vehicles in the year 2001 has changed the complete air quality scenario of Delhi. The dynamic emission factors of criteria pollutants viz. carbon monoxide (CO), nitrogen oxide (NOx) and particulate matter (PM10) for all types of vehicles have been developed after, which are based on the several factors such as regulated emission limits, number of vehicle deterioration, vehicle increment, vehicle age etc. These emission factors are found to be decreased continuously throughout the study years 2003-2012. The International Vehicle Emissions (IVE) model is used to estimate the emissions of criteria pollutants by utilizing a dataset available from field observations at different traffic intersections in Delhi. Thus the vehicular emissions, based on dynamic emission factors have been estimated for the years 2003-2012, which are found to be comparable with the monitored concentrations at different locations in Delhi. It is noticed that the total emissions of CO, NOx, and PM10 are increased by 45.63%, 68.88% and 17.92%, respectively up to the year 2012 and the emissions of NOx and PM10 are grown continuously with an annual average growth rate of 5.4% and 1.7% respectively.

Climate and health relevant emissions from in-use Indian three-wheelers fueled by natural gas and gasoline.

PubMed

Reynolds, Conor C O; Grieshop, Andrew P; Kandlikar, Milind

2011-03-15

Auto-rickshaws in India use different fuels and engine technologies, with varying emissions and implications for air quality and climate change. Chassis dynamometer emission testing was conducted on 30 in-use auto-rickshaws to quantify the impact of switching from gasoline to compressed natural gas (CNG) in spark-ignition engines. Thirteen test vehicles had two-stroke CNG engines (CNG-2S) and 17 had four-stroke CNG engines (CNG-4S), of which 11 were dual-fuel and operable on a back-up gasoline (petrol) system (PET-4S). Fuel-based emission factors were determined for gaseous pollutants (CO(2), CH(4), NO(X), THC, and CO) and fine particulate matter (PM(2.5)). Intervehicle variability was high, and for most pollutants there was no significant difference (95% confidence level) between "old" (1998-2001) and "new" (2007-2009) age-groups within a given fuel-technology class. Mean fuel-based PM(2.5) emission factor (mean (95% confidence interval)) for CNG-2S (14.2 g kg(-1) (6.2-26.7)) was almost 30 times higher than for CNG-4S (0.5 g kg(-1) (0.3-0.9)) and 12 times higher than for PET-4S (1.2 g kg(-1) (0.8-1.7)). Global warming commitment associated with emissions from CNG-2S was more than twice that from CNG-4S or PET-4S, due mostly to CH(4) emissions. Comprehensive measurements and data should drive policy interventions rather than assumptions about the impacts of clean fuels.

A Review of Programs That Targeted Environmental Determinants of Aboriginal and Torres Strait Islander Health

PubMed Central

Johnston, Leah; Doyle, Joyce; Morgan, Bec; Atkinson-Briggs, Sharon; Firebrace, Bradley; Marika, Mayatili; Reilly, Rachel; Cargo, Margaret; Riley, Therese; Rowley, Kevin

2013-01-01

Objective: Effective interventions to improve population and individual health require environmental change as well as strategies that target individual behaviours and clinical factors. This is the basis of implementing an ecological approach to health programs and health promotion. For Aboriginal People and Torres Strait Islanders, colonisation has made the physical and social environment particularly detrimental for health. Methods and Results: We conducted a literature review to identify Aboriginal health interventions that targeted environmental determinants of health, identifying 21 different health programs. Program activities that targeted environmental determinants of health included: Caring for Country; changes to food supply and/or policy; infrastructure for physical activity; housing construction and maintenance; anti-smoking policies; increased workforce capacity; continuous quality improvement of clinical systems; petrol substitution; and income management. Targets were categorised according to Miller’s Living Systems Theory. Researchers using an Indigenous community based perspective more often identified interpersonal and community-level targets than were identified using a Western academic perspective. Conclusions: Although there are relatively few papers describing interventions that target environmental determinants of health, many of these addressed such determinants at multiple levels, consistent to some degree with an ecological approach. Interpretation of program targets sometimes differed between academic and community-based perspectives, and was limited by the type of data reported in the journal articles, highlighting the need for local Indigenous knowledge for accurate program evaluation. Implications: While an ecological approach to Indigenous health is increasingly evident in the health research literature, the design and evaluation of such programs requires a wide breadth of expertise, including local Indigenous knowledge. PMID:23939388

Hazards of heavy metal contamination.

PubMed

Järup, Lars

2003-01-01

The main threats to human health from heavy metals are associated with exposure to lead, cadmium, mercury and arsenic. These metals have been extensively studied and their effects on human health regularly reviewed by international bodies such as the WHO. Heavy metals have been used by humans for thousands of years. Although several adverse health effects of heavy metals have been known for a long time, exposure to heavy metals continues, and is even increasing in some parts of the world, in particular in less developed countries, though emissions have declined in most developed countries over the last 100 years. Cadmium compounds are currently mainly used in re-chargeable nickel-cadmium batteries. Cadmium emissions have increased dramatically during the 20th century, one reason being that cadmium-containing products are rarely re-cycled, but often dumped together with household waste. Cigarette smoking is a major source of cadmium exposure. In non-smokers, food is the most important source of cadmium exposure. Recent data indicate that adverse health effects of cadmium exposure may occur at lower exposure levels than previously anticipated, primarily in the form of kidney damage but possibly also bone effects and fractures. Many individuals in Europe already exceed these exposure levels and the margin is very narrow for large groups. Therefore, measures should be taken to reduce cadmium exposure in the general population in order to minimize the risk of adverse health effects. The general population is primarily exposed to mercury via food, fish being a major source of methyl mercury exposure, and dental amalgam. The general population does not face a significant health risk from methyl mercury, although certain groups with high fish consumption may attain blood levels associated with a low risk of neurological damage to adults. Since there is a risk to the fetus in particular, pregnant women should avoid a high intake of certain fish, such as shark, swordfish and tuna; fish (such as pike, walleye and bass) taken from polluted fresh waters should especially be avoided. There has been a debate on the safety of dental amalgams and claims have been made that mercury from amalgam may cause a variety of diseases. However, there are no studies so far that have been able to show any associations between amalgam fillings and ill health. The general population is exposed to lead from air and food in roughly equal proportions. During the last century, lead emissions to ambient air have caused considerable pollution, mainly due to lead emissions from petrol. Children are particularly susceptible to lead exposure due to high gastrointestinal uptake and the permeable blood-brain barrier. Blood levels in children should be reduced below the levels so far considered acceptable, recent data indicating that there may be neurotoxic effects of lead at lower levels of exposure than previously anticipated. Although lead in petrol has dramatically decreased over the last decades, thereby reducing environmental exposure, phasing out any remaining uses of lead additives in motor fuels should be encouraged. The use of lead-based paints should be abandoned, and lead should not be used in food containers. In particular, the public should be aware of glazed food containers, which may leach lead into food. Exposure to arsenic is mainly via intake of food and drinking water, food being the most important source in most populations. Long-term exposure to arsenic in drinking-water is mainly related to increased risks of skin cancer, but also some other cancers, as well as other skin lesions such as hyperkeratosis and pigmentation changes. Occupational exposure to arsenic, primarily by inhalation, is causally associated with lung cancer. Clear exposure-response relationships and high risks have been observed.

Sulfur solubility in hydrous Etna Basalt at temperatures from 1150 to 1250 °C and 200 MPa

NASA Astrophysics Data System (ADS)

Beermann, O.; Nowak, N.; Botcharnikov, R. E.; Holtz, F.

2009-04-01

Degassing of magmatic volatiles is strongly dependent on fluid-melt interaction at the oneset of degassing under given pressure and temperature. Most magmatic fluids are composed of hydrous multicomponental mixtures, e.g. H-O-C-S-Cl-F-Br bearing fluids. In particular the partitioning behaviour of S and Cl between basaltic melt and hydrous fluid is of interest, because the S/Cl ratio of emitted volcanic gasses correlate to the eruption style (e.g. [1], [2], [3]). In particular, this was also observed for the 2002 eruption of Mt. Etna (Sicily) [4], which is one of the worlds most active and best investigated volcanoes. Since now, there even exist no reliable data on the solubility of sulfur in hydrous silicic melts at geologic relevant temperatures for basaltic magmas (above 1050 °C), because sulfur is known to be a very aggressive component limiting the application of experimental approaches that use noble metal capsules, especially Pt and AuPd. Thus, the experiments in this study, concerning the solubility of S in natural hydrous Etna basalt at 200 MPa and temperatures from 1150 to 1250 °C at fO2 ~ NNO + 2.5 and 1200 °C at fO2 ~ NNO, were performed in olivine-AuPd double capsules, using single crystal olivine capsules (San Carlos olivine) as sample containers, which were inserted into outer Au80Pd20 capsules. The starting material was a fused and water presaturated trachybasalt from Mt. Etna (2001 eruption), containing 5 wt.% H2O. For sulfur source pyrrhotine (FeS) was used, obtaining initial S concentrations between 1-1.5 wt.% (with respect to the amount of starting material). For some experiments an olivine disc was placed between FeS and starting glass powder to avoid FeS dispersion in the melt. All experiments were conducted in internally heated argon pressure vessels (IHPV) equipped with rapid quench device. For the reduced runs an Ar-H2 mixture was load into the vessel and the H2 pressure was monitored, using the shaw membrane technique. The experimental run time was 6-24 h at 1200, 24 h at 1250°C and 67 h at 1150 °C. All glasses obtained from these experiments contained FeS and were enriched in MgO due to reequilibration with MgO-rich olivine. Independent on the run duration, each of the experimental glasses had large variations of S concentration, ranging from 500 to 1600 ppm S at ~ NNO and 250 to 3000 ppm S at ~ NNO + 2.5 (calculated by the S peak shift of WDS spectra, recorded by electron microprobe analysis), where the highest S concentrations were measured near to the FeS source material. However, no direct dependence of temperature on the S solubility and, furthermore, no correlation on S concentration, dependent on the distance to the FeS source was observed, indicating that mobilisation of S seems to be dominated by other mechanisms (e.g. convection) than diffusion. Water concentrations of H2O-presaturated basaltic glasses decreased from 5 wt.% to ~ 2 wt.% (IR-analysis). No sulfur could be detected outside the olivine containers, improoving this experimental setup to be a sufficient barrier for sulfur or S-rich compounds. To get more reliable data, a longer run duration (> 3 d) and a more detailed determination of S species, prevailing in the glasses, is required. [1] Thordarson et al. (1996) Bull. Volcanol. 58, 205-225. [2] Harms & Schmincke (2000) Contrib. Mineral. Petrol. 138, 84-98. [3] Webster et al. (2001) Mineral. Petrol. 73, 177-200. [4] Aiuppa et al. (2004) EPSL 222, 469-483.

Crustal Anatexis by Upwelling Mantle Melts in the N.Atlantic Igneous Province: the Isle of Rum, NW Scotland.

NASA Astrophysics Data System (ADS)

Hertogen, J.; Meyer, R.; Nicoll, G.; Troll, V. R.; Ellam, R. M.; Emeleus, C. H.

2008-12-01

Crustal anatexis is a common process in the rift-to-drift evolution during continental breakup and the formation of Volcanic Rifted Margins (VRM) systems. 'Early felsic-later mafic' volcanic rock associations on the Continent Ocean Boundary (COB) of the N.Atlantic Ocean have been sampled by ODP drilling on the SE Greenland margin and the the Vøring Plateau (Norwegian Sea). Such associations also occur further inland in the British Paleocene Igneous Province, such as on the Isle of Rum (e.g., Troll et al., Contrib. Min. Petrol., 2004, 147, p.722). Sr and Nd isotope and trace element geochemistry show that the Rum rhyodacites are the products of melting of Lewisian amphibolite gneiss. There are no indications of a melt contribution from Lewisian granulite gneiss. The amphibolite gneiss parent rock had experienced an ancient Cs and Rb loss, possibly during a Caledonian event, which caused 87Sr/86Sr heterogeneity in the crustal source of silicic melts. The dacites and early gabbros of Rum are mixtures of crustal melts and primary mantle melts. Rare Earth Element modelling shows that late stage picritic melts on Rum are close analogues for the parent melts of the Rum Layered Suite, and for the mantle melts that caused crustal anatexis of the Lewisian gneiss. These primary mantle melts have close affinities to MORB whose trace element content varies from slightly depleted to slightly enriched. The 'early felsic-later mafic' volcanic associations from Rum, and from the now drowned seaward dipping wedges on the shelf of SE Greenland and on the Vøring Plateau show geochemical differences that result from variations in the regional crustal composition and the depth at which crustal anatexis took place.

Bioremediation of diesel contamination at an underground storage tank site: a spatial analysis of the microbial community.

PubMed

Andreolli, Marco; Albertarelli, Nicola; Lampis, Silvia; Brignoli, Pierlorenzo; Khoei, Nazaninalsadat Seyed; Vallini, Giovanni

2016-01-01

The present study reports on a real case of contamination due to the chronic leakage of diesel fuel from an underground tank at a dismissed service station. Speciation of the microbial community according to both lateral and vertical gradients from the origin of the contaminant release was analyzed by means of the PCR-DGGE technique. Moreover, the effects of a landfarming treatment on both the microbial community structure and the abatement of contamination were analyzed. The concentration of total petrol hydrocarbons (TPHs) decreased along the horizontal gradient (from 7042.2 ± 521.9 to 112.2 ± 24.3 mg kg(-1)), while increased downwards from the position of the tank (from 502.6 ± 43.7 to 4972.5 ± 275.3 mg kg(-1)). PCR-DGGE analyses and further statistical treatment of the data indicated a correlation between structure of the bacterial communities and amount of diesel fuel contamination. On the other hand, level of contamination, soil texture and depth were shown to affect the fungal community. Chloroflexi and Ascomycota were the most abundant microbes ascertained through culture-independent procedures. Landfarming promoted 91.6 % reduction of TPHs in 75 days. Furthermore, PCR-DGGE analyses evidenced that both bacterial and fungal communities of the treated soil were restored to the pristine conditions of uncontaminated topsoil. The present study demonstrated that bacterial and fungal communities were affected differently by soil factors such as level of hydrocarbon contamination as well as soil depth and texture. This report shows that a well-planned landfarming treatment can drive the restoration of the soil in terms of both abatement of the contaminants and resilience of the microbial community structure.

Product retrieval time in small tobacco retail outlets before and after the Australian plain packaging policy: real-world study.

PubMed

Wakefield, Melanie; Bayly, Megan; Scollo, Michelle

2014-01-01

We aimed to assess change in cigarette pack retrieval time in small retail outlets following the introduction of plain packaging in Australia in 1 December 2012. A sample of 303 milk bars, convenience stores, petrol stations and newsagents was selected in four capital cities, stratified by area socioeconomic status. In June and September (baseline months), the first 2 weeks of December 2012, and February 2013, stores were visited by trained fieldworkers who requested a cigarette pack of a pre-determined brand, variant and pack size, unobtrusively recording the time from the end of the request to when the pack was scanned or placed on the counter. In multivariate analysis, December retrieval time (12.43 s) did not differ from June (10.91 s; p=0.410) or February (10.37 s; p=0.382), but was slower than September (9.84 s; p=0.024). In December, retrieval time declined as days after plain packaging implementation increased (β=-0.21, p=0.011), returning to the baseline range by the second week of implementation. This pattern was not observed in baseline months or in February. Sensitivity analyses showed that results were robust to the variability in purchasing circumstances in tobacco retail outlets. Retailers quickly gained experience with the new plain packaging legislation, evidenced by retrieval time having returned to the baseline range by the second week of implementation and remaining so several months later. The long retrieval times predicted by tobacco industry-funded retailer groups and the consequent costs they predicted would fall upon small retailers from plain packaging are unlikely to eventuate.

Chemical signatures of the Anthropocene in the Clyde estuary, UK: sediment-hosted Pb, (207/206)Pb, total petroleum hydrocarbon, polyaromatic hydrocarbon and polychlorinated biphenyl pollution records.

PubMed

Vane, C H; Chenery, S R; Harrison, I; Kim, A W; Moss-Hayes, V; Jones, D G

2011-03-13

The sediment concentrations of total petroleum hydrocarbons (TPHs), polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), Pb and (207/206)Pb isotope ratios were measured in seven cores from the middle Clyde estuary (Scotland, UK) with an aim of tracking the late Anthropocene. Concentrations of TPHs ranged from 34 to 4386 mg kg(-1), total PAHs from 19 to 16,163 μg kg(-1) and total PCBs between less than 4.3 to 1217 μg kg(-1). Inventories, distributions and isomeric ratios of the organic pollutants were used to reconstruct pollutant histories. Pre-Industrial Revolution and modern non-polluted sediments were characterized by low TPH and PAH values as well as high relative abundance of biogenic-sourced phenanthrene and naphthalene. The increasing industrialization of the Clyde gave rise to elevated PAH concentrations and PAH isomeric ratios characteristic of both grass/wood/coal and petroleum and combustion (specifically petroleum combustion). Overall, PAHs had the longest history of any of the organic contaminants. Increasing TPH concentrations and a concomitant decline in PAHs mirrored the lessening of coal use and increasing reliance on petroleum fuels from about the 1950s. Thereafter, declining hydrocarbon pollution was followed by the onset (1950s), peak (1965-1977) and decline (post-1980s) in total PCB concentrations. Lead concentrations ranged from 6 to 631 mg kg(-1), while (207/206)Pb isotope ratios spanned 0.838-0.876, indicative of various proportions of 'background', British ore/coal and Broken Hill type petrol/industrial lead. A chronology was established using published Pb isotope data for aerosol-derived Pb and applied to the cores.

Power supplies and equipment for military field research: lessons from the British Service Dhaulagiri Research Expedition 2016.

PubMed

Howard, Matt; Bakker-Dyos, J; Gallagher, L; O'Hara, J P; Woods, D; Mellor, A

2018-02-01

The British Service Dhaulagiri Research Expedition (BSDMRE) took place from 27 March to 31 May 2016. The expedition involved 129 personnel, with voluntary participation in nine different study protocols. Studies were conducted in three research camps established at 3600, 4600 and 5140 m and involved taking and storing blood samples, cardiac echocardiography and investigations involving a balance plate. Research in this remote environment requires careful planning in order to provide a robust and resilient power plan. In this paper we aim to report the rationale for the choices we made in terms of power supply, the equipment used and potential military applicability. This is a descriptive account from the expedition members involved in planning and conducting the medical research. Power calculations were used to determine estimates of requirement prior to the expedition. The primary sources used to generate power were internal combustion engine (via petrol fuelled electric generators) and solar panels. Having been generated, power was stored using lithium-ion batteries. Special consideration was given to the storage of samples taken in the field, for which electric freezers and dry shippers were used. All equipment used functioned well during the expedition, with the challenges of altitude, temperature and transport all overcome due to extensive prior planning. Power was successfully generated, stored and delivered during the BSDMRE, allowing extensive medical research to be undertaken. The challenges faced and overcome are directly applicable to delivering military medical care in austere environments, and lessons learnt can help with the planning and delivery of future operations, training exercises or expeditions. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Estimativas de possiveis recursos de petroleo e gas na America Central e na America do Sul [Estimates of possible petroleum and gas resources in Central American and South America

USGS Publications Warehouse

Schenk, C.S.

2001-01-01

O U.S. Geological Survey recentemente completou estimativas de possíveis recursos de petróleo e gás em 130 áreas petrolíferas pré-determinadas no mundo (USGS, 2000). Vinte e três destas áreas ficam na América do Sul, na América Central, e no Caribe (fig. 1). Os resultados estão apresentados na tabela 1. Nas 23 áreas, estimamos um total de 105 BBO e um total de 487 TCFG. A região composta de América Central mais América do Sul ficou em terceiro lugar no mundo em termos de possíveis recursos de petróleo e gás. No primeiro lugar ficou o Oriente Médio e no segundo lugar ficou a antiga União Soviética (USGS, 2000). As áreas com maiores probabilidades de encontrar depósitos gigantes de petróleo e gás se localizam nas áreas do Oceano Atlântico começando com a Bacia de Santos no sul até a Bacia Guyana-Suriname no norte. As possibilidades de existirem depósitos gigantes são maiores nas áreas submersas do mar até profundidades de 3,600 m. Diversos depósitos gigantes de petróleo foram descobertos no mar na Bacia de Campos e ainda podem serem encontrados depósitos similares na Bacia de Campos e suas imediações.

[Experimental Methods and Result Analysis of a Variety of Spectral Reflectance Properties of the Thin Oil Film].

PubMed

Ye, Zhou; Liu, Li; Wei, Chuan-xin; Gu, Qun; An, Ping-ao; Zhao, Yue-jiao; Yin, Da-yi

2015-06-01

In order to analysis the oil spill situation based on the obtained data in airborne aerial work, it's needed to get the spectral reflectance characteristics of the oil film of different oils and thickness as support and to select the appropriate operating band. An experiment is set up to measure the reflectance spectroscopy from ultraviolet to near-infrared for the film of five target samples, which means petrol, diesel, lubricating oil, kerosene and fossil, using spectral measurement device. The result is compared with the reflectance spectra of water in the same experimental environment, which shows that the spectral reflection characteristics of the oil film are related to the thickness and the type of the oil film. In case of the same thickness, the spectral reflectance curve of different types of film is far different, and for the same type of film, the spectral reflectance curve changes accordingly with the change of film thickness, therefore in terms of the single film, different film thickness can be distinguished by reflectance curves. It also shows that in terms of the same film thickness, the reflectance of diesel, kerosene, lubricants reaches peak around 380 nm wavelength, obviously different from the reflectance of water, and that the reflectance of crude oil is far less than that of water in more than 340 nm wavelength, and the obtained reflection spectrum can be used to distinguish between different types of oil film to some extent. The experiment covers main types of spilled oil, with data comprehensively covering commonly used detect spectral bands, and quantitative description of the spectral reflectance properties of film. It provides comprehensive theoretical and data support for the selection of airborne oil spill detection working band and the detection and analysis of water-surface oil spill.

Homogeneous, heterogeneous and enzymatic catalysis for transesterification of high free fatty acid oil (waste cooking oil) to biodiesel: a review.

PubMed

Lam, Man Kee; Lee, Keat Teong; Mohamed, Abdul Rahman

2010-01-01

In the last few years, biodiesel has emerged as one of the most potential renewable energy to replace current petrol-derived diesel. It is a renewable, biodegradable and non-toxic fuel which can be easily produced through transesterification reaction. However, current commercial usage of refined vegetable oils for biodiesel production is impractical and uneconomical due to high feedstock cost and priority as food resources. Low-grade oil, typically waste cooking oil can be a better alternative; however, the high free fatty acids (FFA) content in waste cooking oil has become the main drawback for this potential feedstock. Therefore, this review paper is aimed to give an overview on the current status of biodiesel production and the potential of waste cooking oil as an alternative feedstock. Advantages and limitations of using homogeneous, heterogeneous and enzymatic transesterification on oil with high FFA (mostly waste cooking oil) are discussed in detail. It was found that using heterogeneous acid catalyst and enzyme are the best option to produce biodiesel from oil with high FFA as compared to the current commercial homogeneous base-catalyzed process. However, these heterogeneous acid and enzyme catalyze system still suffers from serious mass transfer limitation problems and therefore are not favorable for industrial application. Nevertheless, towards the end of this review paper, a few latest technological developments that have the potential to overcome the mass transfer limitation problem such as oscillatory flow reactor (OFR), ultrasonication, microwave reactor and co-solvent are reviewed. With proper research focus and development, waste cooking oil can indeed become the next ideal feedstock for biodiesel.

Don't be a flamin' fool: effectiveness of an adult burn prevention media campaign in two regions in Queensland, Australia--an interventional study.

PubMed

Muller, Michael J; Dulhunty, Joel M; Paratz, Jennifer D; Harrison, John M; Redman, Bruce R

2013-02-01

Major burn injuries cause devastating physical and psychosocial morbidity, combined with significant health care and community costs. The aim of this study was to evaluate the effectiveness of a targeted burn prevention message on burn safety knowledge and behavior. An 11-year retrospective review of patients admitted to an adult tertiary burn center identified flammable liquid burn injuries in males older than 15 years as 23% of admissions and the most common preventable injury. Burn safety knowledge and experience were measured in a single-blinded, controlled, restricted (male, >15 years), interventional, (therapeutic) prevention study using a total of 2,053 computer-assisted telephone interviews in an intervention region (IR) and control region. A two-week multimedia campaign with the theme "Don't Be a Flamin' Fool" was delivered in the IR. The preintervention survey revealed that 13% (218 of 1,637) reported having previously had a gasoline (petrol) burn. Following the intervention, there was a higher percentage of respondents in the IR that had seen or heard a burn prevention message in the previous 3 months (51% vs. 10%; p < 0.001) and perceived that gasoline was a danger when used to start a fire (97% vs. 91%; p = 0.001), that any volume of gasoline was unsafe (85% vs. 65%; p < 0.001), and that gasoline can explode (96% vs. 92%; p = 0.001). Awareness and memory reverted to preintervention levels at 12 months. Eighty-three percent of respondents (100 of 120) who had seen the "Flamin' Fool" campaign thought it was effective in getting its message across. This collaborative study found that a media prevention message had a significant impact on burn safety knowledge, which diminished over time.

An updated Holocene sea-level curve for the Delaware coast

USGS Publications Warehouse

Nikitina, D.L.; Pizzuto, J.E.; Schwimmer, R.A.; Ramsey, K.W.

2000-01-01

We present an updated Holocene sea-level curve for the Delaware coast based on new calibrations of 16 previously published radiocarbon dates (Kraft, 1976; Belknap and Kraft, 1977) and 22 new radiocarbon dates of basal peat deposits. A review of published and unpublished 137Cs and 210Pb analyses, and tide gauge data provide the basis for evaluating shorter-term (102 yr) sea-level trends. Paleosea-level elevations for the new basal peat samples were determined from the present vertical zonation of marsh plants relative to mean high water along the Delaware coast and the composition of plant fossils and foraminifera. Current trends in tidal range along the Delaware coast were used to reduce elevations from different locations to a common vertical datum of mean high water at Breakwater Harbor, Delaware. The updated curve is similar to Belknap and Kraft's [J. Sediment. Petrol., 47 (1977) 610-629] original sea-level curve from 12,000 to about 2000 yr BP. The updated curve documents a rate of sea-level rise of 0.9 mm/yr from 1250 yr BP to present (based on 11 dates), in good agreement with other recent sea-level curves from the northern and central U.S. Atlantic coast, while the previous curve documents rates of about 1.3 mm/yr (based on 4 dates). The precision of both estimates, however, is very low, so the significance of these differences is uncertain. A review of 210Pb and 137Cs analyses from salt marshes of Delaware indicates average marsh accretion rates of 3 mm/yr for the last 100 yr, in good agreement with shorter-term estimates of sea-level rise from tide gauge records. ?? 2000 Elsevier Science B.V.

Economic incentive in community nursing: attraction, rejection or indifference?

PubMed Central

Kingma, Mireille

2003-01-01

Background It is hard to imagine any period in time when economic issues were more visible in health sector decision-making. The search for measures that maximize available resources has never been greater than within the present decade. A staff payroll represents 60%-70% of budgeted health service funds. The cost-effective use of human resources is thus an objective of paramount importance. Using incentives and disincentives to direct individuals' energies and behaviour is common practice in all work settings, of which the health care system is no exception. The range and influence of economic incentives/disincentives affecting community nurses are the subject of this discussion paper. The tendency by nurses to disregard, and in many cases, deny a direct impact of economic incentives/disincentives on their motivation and professional conduct is of particular interest. The goal of recent research was to determine if economic incentives/disincentives in community nursing exist, whether they have a perceivable impact and in what areas. Conclusion Understanding the value system of community nurses and how they respond to economic incentives/disincentives facilitates the development of reward systems more likely to be relevant and strategic. If nurse rewards are to become more effective organizational tools, the data suggest that future initiatives should: • Improve nurses' salary/income relativities (e.g. comparable pay/rates); • Provide just compensation for job-related expenses (e.g. petrol, clothing); • Introduce promotional opportunities within the clinical area, rewarding skill and competence development; • Make available a range of financed rewards. - Direct (e.g. subsidized education, additional leave, insurance benefits); - Indirect (e.g. better working conditions, access to professional support network, greater participation in decision-making bodies). PMID:12904253

Effect of petroleum-derived substances on life history traits of black bean aphid (Aphis fabae Scop.) and on the growth and chemical composition of broad bean.

PubMed

Rusin, Milena; Gospodarek, Janina; Nadgórska-Socha, Aleksandra; Barczyk, Gabriela

2017-04-01

The aim of the study was to determine the effects of various petroleum-derived substances, namely petrol, diesel fuel and spent engine oil, on life history traits and population dynamics of the black bean aphid Aphis fabae Scop. and on growth and chemical composition of its host plant Vicia faba L. Each substance was tested separately, using two concentrations (9 g kg -1 and 18 g kg -1 ). The experiment was conducted in four replications (four pots with five plants in each pot per treatment). Plants were cultivated in both control and contaminated soils. After six weeks from soil contamination and five weeks from sowing the seeds, observations of the effect of petroleum-derived substances on traits of three successive generations of aphids were conducted. Aphids were inoculated separately on leaves using cylindrical cages hermetically closed on both sides. Contamination of aphid occurred through its host plant. Results showed that all tested substances adversely affected A. fabae life history traits and population dynamics: extension of the prereproductive period, reduction of fecundity and life span, reduction of the population intrinsic growth rate. In broad bean, leaf, roots, and shoot growth was also impaired in most conditions, whereas nutrient and heavy metal content varied according to substances, their concentration, as well as plant part analysed. Results indicate that soil contamination with petroleum-derived substances entails far-reaching changes not only in organisms directly exposed to these pollutants (plants), but also indirectly in herbivores (aphids) and consequently provides information about potential negative effects on further links of the food chain, i.e., for predators and parasitoids.

Phosphorus as indicator of magmatic olivine residence time, morphology and growth rate

NASA Astrophysics Data System (ADS)

Sobolev, Alexander; Batanova, Valentina

2015-04-01

Phosphorus is among of slowest elements by diffusion rate in silicate melts and crystals (e.g. Spandler et al, 2007). In the same time it is moderately incompatible to compatible with olivine (Brunet & Chazot, 2001; Grant & Kohn, 2013). This makes phosphorus valuable tracer of olivine crystallization in natural conditions. Indeed, it is shown that natural magmatic olivine crystals commonly posses strong and complicated zoning in phosphorus (Milman-Barris et al, 2008; Welsch et al, 2014). In this paper we intend to review phosphorus behavior in olivine in published experimental and natural olivine studies and present large set of new EPMA data on phosphorus zoning in olivine phenocrysts from MORBs, OIBs, komatiites and kimberlites. We will show that sharp olivine zones enriched in phosphorus by a factor of 10-20 over prediction by equilibrium partition may be due to formation of P-rich boundary layer on the interface of fast growing olivine. This is proved by finding of small-size (normally 10 mkm or less) exceptionally P-rich melt inclusions in olivine, which are otherwise similar in composition to typical melt. These observations could provide potential olivine growth speedometer. We will also demonstrate, that sharp zoning in phosphorus may provide valuable information on the residence time of olivine crystals in different environments: magma chambers and conduits as well as mantle sources. This study has been founded by Russian Science Foundation grant 14-17-00491. References: Spandler, et al, 2007, Nature, v. 447, p. 303-306; Brunet & Chazot, 2001, Chemical Geology, v. 176, p. 51-72; Grant & Kohn, 2013, American Mineralogist, v. 98, p. 1860-1869; Milman-Barris et al, 2008, Contr. Min. Petrol. v. 155, p.739-765; Welsch et al, 2014, Geology, v. 42, p.867-870.

Exposure to particles and nitrogen dioxide among taxi, bus and lorry drivers.

PubMed

Lewné, Marie; Nise, Gun; Lind, Marie-Louise; Gustavsson, Per

2006-03-01

The aims of this study have been to investigate the occurrence of systematic differences in the personal exposure to motor exhaust between different groups of taxi, bus and lorry drivers, and to study if these are influenced by the choice of exposure indicator. We used one indicator of the gaseous phase, nitrogen dioxide (NO(2)), and one of the particle phase (measured by DataRAM), of the exhausts. A total of 121 drivers were included in the study: 39 taxi drivers, 42 bus drivers and 40 lorry drivers. Personal measurements were performed during one working day. Nitrogen dioxide was measured with passive diffusive samplers and particles with Data-RAM, a logging instrument using nephelometric monitoring. The instrument measures particles between 0.1 and 10 microm in size. The average exposure to NO(2) for lorry drivers was 68 microg/m(3); for bus drivers 60 microg/m(3) and for taxi drivers 48 microg/m(3). For particles the exposure was 57 microg/m(3) for lorry drivers, 44 microg/m(3) for bus drivers and 26 microg/m(3) for taxi drivers. The result remained unchanged when exposures were adjusted for variation in urban background levels of NO(2) and particulate matter with an aerodynamic diameter <10 microm (PM(10)). Lorry drivers experienced the highest exposure and taxi drivers the lowest with bus drivers in an intermediate position, regardless of whether NO(2) or particles were used as exposure indicator. The levels of both NO(2) and particles were higher for bus drivers in the city than for them driving in the suburbs. Using diesel or petrol as a fuel for taxis had no influence on the exposure for the drivers, indicating that the taxi drivers' exposure mainly depends on exhaust from surrounding traffic.

Investigation of hot cracking resistance of 2205 duplex steel

NASA Astrophysics Data System (ADS)

Adamiec, J.; Ścibisz, B.

2010-02-01

Austenitic duplex steel of the brand 2205 according to Avesta Sheffield is used for welded constructions (pipelines, tanks) in the petrol industry, chemical industry and food industry. It is important to know the range of high-temperature brittleness in designing welding technology for constructions made of this steel type. There is no data in literature concerning this issue. High-temperature brittleness tests using the simulator of heat flow device Gleeble 3800 were performed. The tests results allowed the evaluation of the characteristic temperatures in the brittleness temperature range during the joining of duplex steels, specifically the nil-strength temperature (NST) and nil-ductility temperatures (NDT) during heating, the strength and ductility recovery temperatures (DRT) during cooling, the Rfparameter (Rf = (Tliquidus - NDT)/NDT) describing the duplex steel inclination for hot cracking, and the brittleness temperature range (BTR). It has been stated that, for the examined steel, this range is wide and amounts to ca. 90 °C. The joining of duplex steels with the help of welding techniques creates a significant risk of hot cracks. After analysis of the DTA curves a liquidus temperature of TL = 1465 °C and a solidus temperature of TS = 1454 °C were observed. For NST a mean value was assumed, in which the cracks appeared for six samples; the temperature was 1381 °C. As the value of the NDT temperature 1367 °C was applied while for DRT the assumed temperature was 1375 °C. The microstructure of the fractures was observed using a Hitachi S-3400N scanning electron microscope (SEM). The analyses of the chemical composition were performed using an energy-dispersive X-ray spectrometer (EDS), Noran System Six of Thermo Fisher Scientific. Essential differences of fracture morphology type over the brittle temperature range were observed and described.

Emission sources of non-methane volatile organic compounds (NMVOCs) and their contribution to photochemical ozone (O3) formation at an urban atmosphere in western India.

NASA Astrophysics Data System (ADS)

Yadav, R.; Sahu, L. K.; Tripathi, N.; Pal, D.

2017-12-01

Atmospheric non-methane volatile organic compounds (NMVOCs) were measured at a sampling site in Udaipur city of western India during 2015 to recognize their pollution levels, variation characteristics, sources and photochemical reactivity. The samples were analyzed for NMVOCs using a Gas Chromatograph equipped with Flame Ionization Detector (GC/FID) and Thermal Desorption (TD) system. The main focus on understand the sources responsible for NMVOC emissions, and evaluating the role of the identified sources towards ozone formation. Hourly variations of various NMVOC species indicate that VOCs mixing ratios were influenced by photochemical removal with OH radicals for reactive species, secondary formation for oxygenated VOCs. In general, higher mixing ratios were observed during winter/pre-monsoon and lower levels during the monsoon season due to the seasonal change in meteorological, transport path of air parcel and boundary layer conditions. The high levels of propane (C3H8) and butane (C4H10) show the dominance of LPG over the study location. The correlation coefficients of typical NMVOC pairs (ethylene/propylene, propylene/isoprene, and ethane/propane) depicted that vehicular emission and natural gas leakages were important sources for atmospheric hydrocarbons in Udaipur. Based on the annual data, PMF analysis suggest the source factors namely biomass burning/ bio-fuel, automobile exhaust, Industrial/ natural gas/power plant emissions, petrol/Diesel, gasoline evaporation, and use of liquid petroleum gas (LPG) contribute to NMVOCs loading. The propylene-equivalent and ozone formation potential of NMVOCs have also been calculated in order to find out their OH reactivity and contribution to the photochemical ozone formation.

Magmatic Longevity Constrained by ID-TIMS U-Pb Dating of Zircon and Titanite

NASA Astrophysics Data System (ADS)

Szymanowski, D.; Wotzlaw, J. F.; Ellis, B. S.; Bachmann, O.; Von Quadt, A.

2016-12-01

Clues about the timescales and thermal conditions associated with the growth and evacuation of large silicic magma reservoirs are frequently drawn from radiometric dating, diffusion modelling, or thermomechanical modelling. A growing amount of petrological and geochronological evidence, supported by thermal modelling, suggests that many silicic magma reservoirs may exist for some 104-106 years in the form of high-crystallinity mushes at relatively low temperatures ( 700-750°C; [1-3]). Geochronological studies addressing this issue typically utilise the U-Pb system in zircon capable of recording extended periods of crystallisation, particularly in evolved calc-alkaline systems that spend most of their lifetime zircon-saturated. In this study, we integrate U-Pb dating of zircon and titanite to investigate the longevity of the magma reservoir that produced the Kneeling Nun Tuff, a 35 Ma, >900 km3 crystal-rich rhyolitic super-eruption from the Mogollon-Datil volcanic field in New Mexico (USA). High-precision ID-TIMS U-Pb dates of single crystals of both zircon and titanite independently record a continuous crystallisation history over >400,000 years. We combine the dating of both accessory phases with textural, major, trace element and isotopic studies of single crystals, placing tight constraints on the thermal conditions of magma accumulation and storage while recording differentiation and rejuvenation processes within the magma reservoir. The results suggest a protracted `cool' upper-crustal storage of magma prior to the Kneeling Nun Tuff eruption followed by a melting event which reduced the magma crystallinity and conditioned it for eruption. [1] Bachmann & Bergantz (2004), J. Petrol. 45, 1565-1582. [2] Gelman et al. (2013), Geology 41, 759-762. [3] Cooper & Kent (2014), Nature 506, 480-483.

Effect of a blackout in pediatric patients with home medical devices during the 2011 eastern Japan earthquake.

PubMed

Nakayama, Tojo; Tanaka, Soichiro; Uematsu, Mitsugu; Kikuchi, Atsuo; Hino-Fukuyo, Naomi; Morimoto, Tetsuji; Sakamoto, Osamu; Tsuchiya, Shigeru; Kure, Shigeo

2014-02-01

during the eastern Japan earthquake in 2011 and the following prolonged blackout, pediatric patients with home medical devices sought electricity at the pediatric department. We retrospectively studied the effect of this earthquake and the following blackout. we hand-reviewed pediatric admission records in Tohoku University Hospital for new inpatients attributed to the earthquake from March 11, 2011 to April 12, 2011. A survey by questionnaire regarding the situation during the earthquake was performed for parents of technology-assisted patients. during the study period, 24 pediatric patients were admitted to the pediatric department. Eighteen technology-assisted pediatric patients, including those with home respirators, accounted for 75% of new pediatric admissions. Patients who were admitted for electricity shortage stayed in the hospital for a mean of 11.0days (3-25days). The questionnaire survey showed that 55% of technology-assisted patients were admitted to medical centers for evacuation. The majority of patients (89%) with ventilators were eventually admitted to medical centers during the earthquake. Most of the parents of technology-assisted patients experienced a prolonged petrol shortage and difficulty in communications with medical centers. the current study suggests that technology-assisted pediatric patients with neurological disorders as the primary disease can overwhelm the capacity of hospital inpatient facilities in certain situations. Disaster preparedness should consider assuring power requirements in healthcare facilities and preparing backup power generators lasting for at least 24h for these patients. Preparing alternative measures for emergent electricity and communications could remedy serious conditions during a disaster. Copyright © 2013 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

UV-sensitive scientific CCD image sensors

NASA Astrophysics Data System (ADS)

Vishnevsky, Grigory I.; Kossov, Vladimir G.; Iblyaminova, A. F.; Lazovsky, Leonid Y.; Vydrevitch, Michail G.

1997-06-01

An investigation of probe laser irradiation interaction with substances containing in an environment has long since become a recognized technique for contamination detection and identification. For this purpose, a near and midrange-IR laser irradiation is traditionally used. However, as many works presented on last ecology monitoring conferences show, in addition to traditional systems, rapidly growing are systems with laser irradiation from near-UV range (250 - 500 nm). Use of CCD imagers is one of the prerequisites for this allowing the development of a multi-channel computer-based spectral research system. To identify and analyze contaminating impurities on an environment, such methods as laser fluorescence analysis, UV absorption and differential spectroscopy, Raman scattering are commonly used. These methods are used to identify a large number of impurities (petrol, toluene, Xylene isomers, SO2, acetone, methanol), to detect and identify food pathogens in real time, to measure a concentration of NH3, SO2 and NO in combustion outbursts, to detect oil products in a water, to analyze contaminations in ground waters, to define ozone distribution in the atmosphere profile, to monitor various chemical processes including radioactive materials manufacturing, heterogeneous catalytic reactions, polymers production etc. Multi-element image sensor with enhanced UV sensitivity, low optical non-uniformity, low intrinsic noise and high dynamic range is a key element of all above systems. Thus, so called Virtual Phase (VP) CCDs possessing all these features, seems promising for ecology monitoring spectral measuring systems. Presently, a family of VP CCDs with different architecture and number of pixels is developed and being manufactured. All CCDs from this family are supported with a precise slow-scan digital image acquisition system that can be used in various image processing systems in astronomy, biology, medicine, ecology etc. An image is displayed directly on a PC monitor through a software support.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, X.; Xiao, Y.; Xu, S.

A co-production system based on Fischer-Tropsch (FT) synthesis reactor and gas turbine was simulated and analyzed. Syngas from entrained bed coal gasification was used as feedstock of the low-temperature slurry phase Fischer-Tropsch reactor. Raw synthetic liquid produced was fractioned and upgraded to diesel, gasoline, and liquid petrol gas (LPG). Tail gas composed of unconverted syngas and FT light components was fed to the gas turbine. Supplemental fuel (NG, or refinery mine gas) might be necessary, which was dependent on gas turbine capacity expander through flow capacity, etc. FT yield information was important to the simulation of this co-production system. Amore » correlation model based on Mobil's two step pilot plant was applied. User models that can predict product yields and cooperate with other units were embedded into Aspen plus simulation. Performance prediction of syngas fired gas turbine was the other key of this system. The increase in mass flow through the turbine affects the match between compressor and turbine operating conditions. The calculation was carried out by GS software developed by Politecnico Di Milano and Princeton University. Various cases were investigated to match the FT synthesis island, power island, and gasification island in co-production systems. Effects of CO{sub 2} removal/LPG recovery, co-firing, and CH{sub 4} content variation were studied. Simulation results indicated that more than 50% of input energy was converted to electricity and FT products. Total yield of gasoline, diesel, and LPG was 136-155 g/N m{sup 3} (CO+H{sub 2}). At coal feed of 21.9 kg/s, net electricity exported to the grid was higher than 100 MW. Total production of diesel and gasoline (and LPG) was 118,000 t (134,000 t)/year. Under the economic analysis conditions assumed in this paper the co-production system was economically feasible.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, Terry Alan; Hogan, Roy E., Jr.; McDaniel, Anthony H.

Two of the most daunting problems facing humankind in the twenty-first century are energy security and climate change. This report summarizes work accomplished towards addressing these problems through the execution of a Grand Challenge LDRD project (FY09-11). The vision of Sunshine to Petrol is captured in one deceptively simple chemical equation: Solar Energy + xCO{sub 2} + (x+1)H{sub 2}O {yields} C{sub x}H{sub 2x+2}(liquid fuel) + (1.5x+.5)O{sub 2} Practical implementation of this equation may seem far-fetched, since it effectively describes the use of solar energy to reverse combustion. However, it is also representative of the photosynthetic processes responsible for much ofmore » life on earth and, as such, summarizes the biomass approach to fuels production. It is our contention that an alternative approach, one that is not limited by efficiency of photosynthesis and more directly leads to a liquid fuel, is desirable. The development of a process that efficiently, cost effectively, and sustainably reenergizes thermodynamically spent feedstocks to create reactive fuel intermediates would be an unparalleled achievement and is the key challenge that must be surmounted to solve the intertwined problems of accelerating energy demand and climate change. We proposed that the direct thermochemical conversion of CO{sub 2} and H{sub 2}O to CO and H{sub 2}, which are the universal building blocks for synthetic fuels, serve as the basis for this revolutionary process. To realize this concept, we addressed complex chemical, materials science, and engineering problems associated with thermochemical heat engines and the crucial metal-oxide working-materials deployed therein. By project's end, we had demonstrated solar-driven conversion of CO{sub 2} to CO, a key energetic synthetic fuel intermediate, at 1.7% efficiency.« less

A comment on: `TitaniQ under pressure: the effect of pressure and temperature on the solubility of Ti in quartz', by Jay B. Thomas, E. Bruce Watson, Frank S. Spear, Philip T. Shemella, Saroj K. Nayak and Antonio Lanzirotti

NASA Astrophysics Data System (ADS)

Wilson, Colin J. N.; Seward, Terry M.; Allan, Aidan S. R.; Charlier, Bruce L. A.; Bello, Léa

2012-08-01

Trace concentrations of Ti in quartz are used to indicate the pressure and temperature conditions of crystallization in the `TitaniQ' geothermobarometer of Thomas et al. (Contrib Miner Petrol 160:743-759, 2010). It utilises the partitioning of Ti into quartz as an indicator of the pressures and/or temperatures of crystal growth. For a given value of TiO2 activity in the system, if temperatures are inferred to ±20 °C, pressure is constrained to ±1 kbar and vice versa. There are significant contrasts, however, between the conclusions from TitaniQ and those for natural quartz (as well as other mineral phases) in volcanic rocks. Application of the TitaniQ model to quartz from the 27 ka Oruanui and 760 ka Bishop high-silica rhyolites, where the values of T, P and TiO2 activity are constrained by other means (Fe-Ti oxide equilibria, melt inclusion entrapment pressures in gas-saturated melts, melt and amphibole compositions), yields inconsistent results. If realistic values are given to any two of these three parameters, then the value of the third is wholly unrealistic. The model yields growth temperatures at or below the granite solidus, pressures in the lower crust or upper mantle, or TiO2 activities inconsistent with the mineralogical and chemical compositions of the magmas. CL imagery and measurements of Ti (and other elements) in quartz are of great value in showing the growth histories and changes in conditions experienced by crystals, but direct linkages to P, T conditions during crystal growth cannot be achieved.

The role of garnet in (Y+REE) mobility during fluid-initiated, localized, solid state dehydration of an amphibole-bearing migmatised granitic gneiss to charnockite

NASA Astrophysics Data System (ADS)

Harlov, D. E.; Anczkiewicz, R.; Johansson, L.

2013-12-01

On either side of 1 m wide granitic pegmatoid dyke, Söndrum stone quarry, Halmstad, SW Sweden, extends a 2.5-3 m wide Opx-bearing dehydration zone (DZ) (650-700 °C; 800 MPa; Opx-Cpx-Bt-Amph-Gt-allanite), which overprints the gneissic banding of the surrounding migmatised granitic gneiss (MGG) (Amph-Bt-Gt-allanite) (Harlov et al., 2006, J Petrol 47, 3). Whole-rock chemistry indicates that dehydration of the MGG was predominantly isochemical. Exceptions include (Y+HREE), Ba, Sr, and F, which are markedly depleted throughout the DZ while LREE-bearing allanite remains unaltered. Systematic trends in the Gt, Bt, Amph, and FAp mineral chemistry across the DZ include depletion in Fe, (Y+HREE), Na, K, F, and Cl, and enrichment in Mg, Mn, Ca, and Ti. Fluid inclusion data suggest that the solid state dehydration event was due to advective transport of a CO2-rich fluid with a minor Cl and F component originating from a tectonic fracture represented today by the pegmatoid dyke. LA-ICPMS analysis of (Y+REE) in Gt (NIST 612 Glass standard; for operating conditions cf. Anczkiewicz et al. 2012 Chem Geol 318-319, 16) across the traverse indicates at least two distinct populations of Gt from the DZ variably depleted in (Y+HREE) and LREE (Fig. 1) by an order of magnitude compared to Gt in the MGG (Fig. 2). Depletion most likely is the result of (Y+HREE) and LREE partitioning from the Gt into the dehydrating fluid to complex with F and Cl. Variable depletion suggests preferred inter-granular pathways for fluid flow through the DZ during the dehydration event allowing some Gt grains greater exposure to the fluid than other Gt grains.

Study of insect succession and rate of decomposition on a partially burned pig carcass in an oil palm plantation in Malaysia.

PubMed

Heo, Chong Chin; Mohamad, Abdullah Marwi; Ahmad, Firdaus Mohd Salleh; Jeffery, John; Kurahashi, Hiromu; Omar, Baharudin

2008-12-01

Insects found associated with corpse can be used as one of the indicators in estimating postmortem interval (PMI). The objective of this study was to compare the stages of decomposition and faunal succession between a partially burnt pig (Sus scrofa Linnaeus) and natural pig (as control). The burning simulated a real crime whereby the victim was burnt by murderer. Two young pigs weighed approximately 10 kg were used in this study. Both pigs died from pneumonia and immediately placed in an oil palm plantation near a pig farm in Tanjung Sepat, Selangor, Malaysia. One pig was partially burnt by 1-liter petrol while the other served as control. Both carcasses were visited twice per day for the first week and once thereafter. Adult flies and larvae on the carcasses were collected and later processed in a forensic entomology laboratory. Results showed that there was no significant difference between the rate of decomposition and sequence of faunal succession on both pig carcasses. Both carcasses were completely decomposed to remain stage after nine days. The species of flies visiting the pig carcasses consisted of blow flies (Chrysomya megacephala, Chrysomya rufifacies, Hemipyrellia ligurriens), flesh fly (Sarcophagidae.), muscid fly (Ophyra spinigera), soldier fly (Hermetia illucens), coffin fly (Phoridae) and scavenger fly (Sepsidae). The only difference noted was in the number of adult flies, whereby more flies were seen in the control carcass. Faunal succession on both pig carcasses was in the following sequence: Calliphoridae, Sarcophagidae, Muscidae, Phoridae and lastly Stratiomyidae. However, there was overlap in the appearance of members of these families. Blowflies continued to oviposit on both carcasses. Hence postmortem interval (PMI) can still be estimated from the partially burnt pig carcass.

An odyssey of environmental pollution: the rise, fall and remobilization of industrial lead in Australia

NASA Astrophysics Data System (ADS)

Taylor, M. P.; Kristensen, L.; Liqin, W.; Harvey, P. J.; Dong, C.; Rouillon, M.

2015-12-01

The use of lead in automobile gasoline resulted in more than 240,000 tonnes of lead being emitted to the Australian environment over its 70-year period of use starting in 1932. The consequences of the emissions and subsequent depositions have resulted in marked contamination of urban and peri-urban aerosols, soils, plants and humans. This paper charts these effects and examines the extent of recovery from one of the most pervasive and persistent environmental pollutants. Lead isotopic composition of Adelaide and Sydney aerosol filters show that air lead composition shifts from values that approximate Broken Hill type ores, the predominant lead source used in gasoline (1.04 206Pb/207Pb and 2.31 208Pb/207Pb), towards ratios that more closely match local uncontaminated soil and bedrock values (Adelaide ~1.19 206Pb/207Pb and ~2.50 208Pb/207Pb; Sydney ~1.15 206Pb/207Pb and 2.48 208Pb/207Pb). Proxy atmospheric measurements from historic wine, lichen and fungi samples extending over 120 years show how both concentration and composition values shifted in the middle to late 20th century to reflect petrol emissions and then recovered rapidly at the end of the century as leaded gasoline consumption declined. For example, lead in wine from South Australia fell from >100 μg/L in the 1960s and 1970s to < 5 μg/L in the 2010s due to the removal of the primary source of atmospheric lead - gasoline. However, measurement of contemporary surface soils, ash produced from wildfires and air filters demonstrate that the effect of depositions persists and industrial lead and other toxic metals (including arsenic, cadmium and nickel) are subject to frequent remobilization. Predicted increases in wildfires and the generation of lead, arsenic and cadmium toxic particulates warrants greater consideration of the risk for vulnerable populations and firefighters who are most exposed.

Size resolved ultrafine particles emission model--a continues size distribution approach.

PubMed

Nikolova, Irina; Janssen, Stijn; Vrancken, Karl; Vos, Peter; Mishra, Vinit; Berghmans, Patrick

2011-08-15

A new parameterization for size resolved ultrafine particles (UFP) traffic emissions is proposed based on the results of PARTICULATES project (Samaras et al., 2005). It includes the emission factors from the Emission Inventory Guidebook (2006) (total number of particles, #/km/veh), the shape of the corresponding particle size distribution given in PARTICULATES and data for the traffic activity. The output of the model UFPEM (UltraFine Particle Emission Model) is a sum of continuous distributions of ultrafine particles emissions per vehicle type (passenger cars and heavy duty vehicles), fuel (petrol and diesel) and average speed representative for urban, rural and highway driving. The results from the parameterization are compared with measured total number of ultrafine particles and size distributions in a tunnel in Antwerp (Belgium). The measured UFP concentration over the entire campaign shows a close relation to the traffic activity. The modelled concentration is found to be lower than the measured in the campaign. The average emission factor from the measurement is 4.29E+14 #/km/veh whereas the calculated is around 30% lower. A comparison of emission factors with literature is done as well and in overall a good agreement is found. For the size distributions it is found that the measured distributions consist of three modes--Nucleation, Aitken and accumulation and most of the ultrafine particles belong to the Nucleation and the Aitken modes. The modelled Aitken mode (peak around 0.04-0.05 μm) is found in a good agreement both as amplitude of the peak and the number of particles whereas the modelled Nucleation mode is shifted to smaller diameters and the peak is much lower that the observed. Time scale analysis shows that at 300 m in the tunnel coagulation and deposition are slow and therefore neglected. The UFPEM emission model can be used as a source term in dispersion models. Copyright © 2011 Elsevier B.V. All rights reserved.

Geochemistry of post-spreading lavas from fossil Mathematician and Galapagos spreading axes, revisited

NASA Astrophysics Data System (ADS)

Tian, L.; Castillo, P. R.; Hilton, D. R.

2010-12-01

The Mathematician Ridge, located west of the northern end of the EPR at about 10-20°N, 110°W, was abandoned during the Pliocene when the Pacific plate captured the Mathematician microplate. The Galapagos Rise, located east of the southern segment of the EPR at about 10-18°S, 95°W, ceased spreading after the Late Miocene capture of the Bauer microplate by the Nazca plate. Here we report new major and trace element and Sr, Nd and Pb isotope data for lavas dredged from seamounts and volcanic ridges along the crest of Mathematician Ridge [Batiza and Vanko, J. Petrol. 26, 1985] and from narrow volcanic ridges built along extinct segments of the Galapagos Rise [Batiza et al., Mar. Geol. 49, 1982]. These lavas consist predominantly of alkalic basalts and their differentiates, similar to the post-spreading alkalic lava series in other fossil spreading axes (e.g., Davidson Seamount, Guide Seamount, Socorro Island, and fossil spreading axes off Baja California Sur) and alkalic lavas from near-ridge seamounts in the eastern Pacific [Castillo et al., G3 11, 2010; Tian et al., sub. to G3]. Collectively, the alkalic lavas have higher incompatible trace element contents and highly/moderately incompatible trace element ratios (e.g., Ba/Zr >1.3, La/Sm >2.7 and Nb/Zr >0.14) than EPR basalts, and are similar to average alkalic OIB. They also have similar 87Sr/86Sr (0.7027 - 0.7037), 143Nd/144Nd (0.51289 - 0.51306) and 206Pb/204Pb (18.70 - 19.84) compositions, which overlap with geochemically enriched (E-) MORB and ~depleted OIB from major hotspot volcanic chains such as Galapagos, Hawaii and Iceland. The new data suggest that intraplate lavas from fossil spreading axes and non-hotspot seamounts in the eastern Pacific share a common enriched source which is geographically dispersed in the upper mantle.

Investigation of production of continuous off axis fibre reinforced thermoplastic material

NASA Astrophysics Data System (ADS)

McDonald, Philip C.

Fibre reinforced composites have been used in the engineering industry for many years since the discovery of glass fibre in 1930 and its first use to reinforce phenolic resin to form Bakelite. Since then thermoplastic and thermosetting composites have spread into almost every industry from marine to aerospace, automotive to motorsport, luggage to the hobby industry and even fashion. This vast range of applications for composite materials is due to their high strength to weight ratio, excellent impact absorption properties, lack of corrosion, and reformability. In recent years a government directive has forced automotive manufacturers to look at lighter and more efficient vehicles to reduce carbon emissions. This can be achieved by using fibre reinforced thermoplastics to replace steel panels throughout the vehicle.Steel panels from a Nissan Qashqai were tested to determine the failure loads of each panel which the replacement thermoplastic material had to match or better. After extensive testing in a laboratory a tailored laminate lay-up with 5 laminate layers has been developed to replace structural steel components in vehicles. This tailored laminate stack up has a higher failure load than the steel components tested from the Nissan Qashqai while reducing the mass by at least 50%. The key drivers within the automotive industry are fuel savings and reduced vehicle mass, the use of this material and the potential it has in the mass production automotive industry can have a high impact on the overall mass of the vehicle which would invariably have a positive effect to the fuel consumption, thereby improving fuel economy in petrol and diesel vehicles, and increasing the range of electric vehicles.Throughout this project a prototype machine was developed and built to achieve mass production of this 5 ply laminate at a rate of more than 345,000 laminates per year with a processing cost of 3 1p making it available to the mass production market. The estimated production cost represents approximately 2.4% of the finished product price.

CO2-SO3-rich (carbonate-sulfate) melt/fluids in the lithosphere beneath El Hierro, Canary Islands.

NASA Astrophysics Data System (ADS)

Oglialoro, E.; Ferrando, S.; Malaspina, N.; Villa, I. M.; Frezzotti, M. L.

2015-12-01

Mantle xenoliths from the island of El Hierro, the youngest of the Canary Islands, have been studied to characterize fluxes of carbon in the lithosphere of an OIB volcanism region. Fifteen xenoliths (4-10 cm in diameter) were collected in a rift lava flow (15-41 ka) at a new xenolith locality in El Julan cliff (S-SW of the island). Peridotites consist of protogranular to porphyroblastic spinel harzburgites, lherzolites, and subordinate dunites. One spinel clinopyroxenite, and one olivine-websterite were also analyzed. Ultramafic xenoliths were classified as HEXO (harzburgite and dunite with exsolved orthopyroxene), HLCO (harzburgite and lherzolite containing orthopyroxene without visible exsolution lamellae), and HTR (transitional harzburgite with exsolved orthopyroxene porphyroclasts, and poikilitic orthopyroxene) following [1]. While HLCO and HTR peridotites contain mostly CO2 fluid inclusions, HEXO peridotites preserve an early association of melt/fluid inclusions containing dominantly carbonate/sulfate/silicate glass, evolving to carbonate/sulfate/phosphate/spinel aggregates, with exsolved CO2 (± carbonates, anhydrite and H2O). Chemical and Raman analyses identify dolomite, Mg-calcite, anhydrite, sulfohalite [Na6(SO4)2FCl] (± other anhydrous and hydrous alkali-sulfates), apatite, and Cr-spinel in the inclusions. Sulfides are noticeably absent. The microstructure and chemical composition of the metasomatic fluids indicate that the peridotites were infiltrated by a carbonate-sulfate-silicate melt/fluid enriched in CO2, H2O, and P. A mantle origin for this fluid is supported by high densities of CO2inclusions (> 1g/cm3), determined by Raman microspectroscopy and cross-checked by microthermometry. Consequently, El Julan peridotites provide the first evidence for liberating oxidized C and S fluxes from the Earth lithosphere in an OIB source region, and suggest that oxidation of sulfide to sulfate can occur during small-degree partial melting of the upper mantle. [1] Neumann et al. (2004) J. Petrol. 45, 2573-2612.

The importance of trenching in paleoseismic studies in Venezuela: brief historical summary

NASA Astrophysics Data System (ADS)

Murria, J.

2009-04-01

Paleoseismic studies have proved to be a powerful tool in seismic hazards assessment by he contributing to asses the seismogenic potential of a given fault by expanding the time window o seismic activity beyond the limits of historical and instrumental seismicity. Trenching has been an essential tool for paleoseismic studies in Venezuela. The first paleoseismic trenching project in Venezuela goes back to 1968 when Compania Shell de Venezuela retained the services of Woodward Clyde and Associates,(WCA), USA to asses the seismic integrity of the earthen dikes of Costa Oriental of Lake Maracaibo Protection System (COLM) in western Venezuela. The study was carried out under the general coordination of this author. An important part of this project included a seismology and seismic geology study under the direction of Geologist L.S. Cluff. This was the first ever study undertaken in Venezuela and included two excavations across the Oca Fault north of the city of Maracaibo. After several years of inactivity, FUNVISIS (The Venezuelan Foundation for Seismological Research) carried out in 1980 a seismic hazard (SHA) for the Uribante Caparo Hydroelectric Project southwest Venezuela. In 1989, MARAVEN, an operating company of PETROLE0S DE VENEUELA S.A. (PDVSA) undertook the project of a products pipeline form Maracaibo to El Vigia, south of Lake Maracaibo. Again, FUNVISIS was contracted to carry out a SHA, which included the digging of 5 trenches, which were supplemented with five more trenches for the COLM project. Trenching activity contined in Venezuela in the framework of SHA project, under the direction of Dr. Audemard. In 2001 Venezuelan trenching experience was exported to the neighboring Colombia as e Dr. Audemard t undertook a palaoseismicity project which included the digging of five trenches. In conclusion, paleoseismicty studies have given us the possibility of extending the scope of both instrumental and historical seismicity by some 10,000 years, trenching has proved for paleoseismic studies to be a valuable to.

Measuring the healthfulness of food retail stores: variations by store type and neighbourhood deprivation

PubMed Central

2014-01-01

Background The consumer nutrition environment has been conceptualised as in-store environmental factors that influence food shopping habits. More healthful in-store environments could be characterised as those which promote healthful food choices such as selling good quality healthy foods or placing them in prominent locations to prompt purchasing. Research measuring the full-range of in-store environmental factors concurrently is limited. Purpose To develop a summary score of ‘healthfulness’ composed of nine in-store factors that influence food shopping behaviour, and to assess this score by store type and neighbourhood deprivation. Methods A cross-sectional survey of 601 retail food stores, including supermarkets, grocery stores and convenience stores, was completed in Hampshire, United Kingdom between July 2010 and June 2011. The survey measured nine variables (variety, price, quality, promotions, shelf placement, store placement, nutrition information, healthier alternatives and single fruit sale) to assess the healthfulness of retail food stores on seven healthy and five less healthy foods that are markers of diet quality. Four steps were completed to create nine individual variable scores and another three to create an overall score of healthfulness for each store. Results Analysis of variance showed strong evidence of a difference in overall healthfulness by store type (p < 0.001). Large and premium supermarkets offered the most healthful shopping environments for consumers. Discount supermarkets, ‘world’, convenience and petrol stores offered less healthful environments to consumers however there was variation across the healthfulness spectrum. No relationship between overall healthfulness and neighbourhood deprivation was observed (p = 0.1). Conclusions A new composite measure of nine variables that can influence food choices was developed to provide an overall assessment of the healthfulness of retail food stores. This composite score could be useful in future research to measure the relationship between main food store and quality of diet, and to evaluate the effects of multi-component food environment interventions. PMID:24884529

[Tobacco smoking and principles of the who framework convention on tobacco control: a review].

PubMed

Melkadze, N

2013-02-01

The aim of a review is to examine the current state of the relevant publications on tobacco smoking, the Guidelines on Protection from Exposure to Tobacco Smoke, and WHO Framework Convention on Tobacco Control (FCTC), which commits countries to protect the public's health by adopting various measures to reduce demand for tobacco. Georgia ratified the treaty in February 2006. In Georgia the implementation of the WHO FCTC is regulated by the "Law on Tobacco Control" (Law). It went into effect in September 2003. Changes and additions to the Law were approved by the Parliament in December 2008 (N 941 - rs) and in December 2010 (№4059-rs). According to Article 10 of the Law, smoking is prohibited at the educational and childcare institutions, medical and pharmaceutical facilities, at the entire area of petrol, gas and gas-distribution stations, in public transport, indoor areas of work and mass gathering... In spite of the legislation rights of non-smokers are very poorly preserved. With this in mind, the Welfare Foundation, the FCTC and the Tobacco Control Alliance, organized a public discussion on enforcing smoke-free laws in Georgia, in December 2012 at Tbilisi Marriott Courtyard Hotel. In order to make public libraries, educational, cultural institutions «de jure» and «de facto» free from tobacco smoke, the campaign against tobacco, which aims to strengthen implementation of the Tobacco Control Law and Regulation should be held in public libraries - not in the hotels. It is necessary to hang a poster - «Environment free from Smoke» at the entrance to buildings where smoking is prohibited throughout. In Rules and regulations for the use of the library there must be a note: smoking is prohibited in the library. We hope that Georgia in the nearest future will be in the list of countries with smoke-free public and work places.

Magnesium Isotopic Composition of Kamchatka Sub-Arc Mantle Peridotites

NASA Astrophysics Data System (ADS)

Hu, Y.; Teng, F. Z.; Ionov, D. A.

2016-12-01

Subduction of the oceanic slab may add a crustal isotopic signal to the mantle wedge. The highly variable Mg isotopic compositions (δ26Mg) of the subducted oceanic crust input[1] and arc lava output[2] imply a distinctive Mg isotopic signature of the mantle wedge. Magnesium isotopic data on samples from the sub-arc mantle are still limited, however. To characterize the Mg isotopic composition of typical sub-arc mantle, 17 large and fresh spinel harzburgite xenoliths from Avacha volcano were analyzed. The harzburgites were formed by 30% melt extraction at ≤ 1 2 GPa and fluid fluxing condition, and underwent possible fluid metasomatism as suggested by distinctively high orthopyroxene mode in some samples, the presence of accessory amphibole and highly variable Ba/La ratios[3]. However, their δ26Mg values display limited variation from -0.32 to -0.21, which are comparable to the mantle average at -0.25 ± 0.07[4]. The overall mantle-like and homogenous δ26Mg of Avacha sub-arc peridotites are consistent with their similar chemical compositions and high MgO contents (> 44 wt%) relative to likely crustal fluids. Furthermore, clinopyroxene (-0.24 ± 0.10, 2SD, n = 5), a late-stage mineral exsolved from high-temperature, Ca-rich residual orthopyroxene, is in broad Mg isotopic equilibrium with olivine (-0.27 ± 0.04, 2SD, n = 17) and orthopyroxene (-0.22 ± 0.06, 2SD, n = 17). Collectively, this study finds that the Kamchatka mantle wedge, as represented by the Avacha peridotites, has a mantle-like δ26Mg, and low-degree fluid-mantle interaction does not cause significant Mg isotope fractionation in sub-arc mantle peridotites. [1] Wang et al., EPSL, 2012 [2] Teng et al., PNAS, 2016 [3] Ionov, J. Petrol., 2010, [4] Teng et al., GCA, 2010.

Prevalence, knowledge, attitude and practice of speeding in two districts in Kenya: Thika and Naivasha.

PubMed

Bachani, Abdulgafoor M; Hung, Yuen Wai; Mogere, Stephen; Akungah, Daniel; Nyamari, Jackim; Stevens, Kent A; Hyder, Adnan A

2013-12-01

In Kenya, RTIs had the second highest increase in disability-adjusted life years between 1990 and 2010, compared to other conditions. This study aims to determine the prevalence, knowledge, attitudes and practices for speeding in Thika and Naivasha districts in Kenya. Direct observations of vehicle speed were conducted at various times during the day and different days of the week on six roads selected based on a multi-stage sampling method in two districts to determine the prevalence of speeding. Roadside KAP interviews were administered to drivers, at motorcycle bays, petrol stations, and rest areas. Eight rounds of speed observations and four rounds of KAP interviews were conducted between July 2010 and November 2012. Results from the speeding observational studies show an overall high proportion of vehicles speeding above posted limits in both districts, with an average of 46.8% in Thika and 40.2% in Naivasha. Trend analysis revealed a greater decline in this prevalence in Thika (OR: 0.804, 95% CI: 0.793-0.814) than in Naivasha (OR: 0.932, 95% CI: 0.919-0.945) over the study period. On average, 58.8% of speeding vehicles in Thika and 57.2% of speeding vehicles in Naivasha travelled at 10 km/h or higher above speed limit. While the majority of respondents agreed that speeding is a cause of road traffic crashes in both Thika (70.3%) and Naivasha (68.7%), knowledge of speed limits at the location of the interview was limited. Enforcement levels also remained low, but subsequent rounds of data collection showed improvement, especially in Thika. This study demonstrates an improvement in the prevalence of speeding in two districts of Kenya over 2010-2012. It also highlights the need for further action to be taken to address the problem, and represents new data on speeding in Kenya and Africa. Copyright © 2013 Elsevier Ltd. All rights reserved.

Prediction of seat belt use among Iranian automobile drivers: application of the theory of planned behavior and the health belief model.

PubMed

Tavafian, Sedigheh Sadat; Aghamolaei, Teamur; Gregory, David; Madani, Abdoulhossain

2011-02-01

Seat belt use plays an important role in traffic safety by reducing the severity of injuries and fatality rates during vehicle accidents. The aim of this study was to investigate predictors of self-reported seat belt use in a sample of automobile drivers in Bandar Abbas, Iran. The theory of planed behavior and the health belief model served as the conceptual framework for the study. The convenience sample consisted of 284 eligible automobile drivers who frequented 8 petrol stations in different geographical areas of the city. Of the drivers approached to participate in the study, 21 declined to take part in the study and 12 other questionnaires were incomplete. Thus, a total of 251 questionnaires were analyzed (response rate=88.4%). A self-administered questionnaire including demographic characteristics and items arising from the theory of planed behavior and health belief model constructs were used to collect data. Data were analyzed using SPSS 16 (version 16, Chicago, IL, USA). The subjects' mean age was 31.6 years (SD=8.7), mostly male (72.9%), and 53.4 percent of them reported that they used their seat belt "often." Multiple regression analyses revealed that from the theory of planed behavior, attitude, subjective norms, and perceived behavioral control significantly predicted intention to use a seat belt (R2=0.38, F=51.1, p<.001); and subjective norms, perceived behavioral control, and behavioral intention significantly predicted seat belt use (R2=0.43, F=45.7, p<.001). Arising from the health belief model, perceived benefits and perceived barriers significantly predicted seat belt use (R2=0.39, F=26.2, p<.001). This study revealed that automobile drivers who perceived more subjective norms, more behavioral control, greater intention to use seat belts as well as more benefits and fewer barriers were more likely to use their seat belts.

Spatial variation in vehicle-derived metal pollution identified by magnetic and elemental analysis of roadside tree leaves

NASA Astrophysics Data System (ADS)

Maher, B. A.; Moore, C.; Matzka, J.

Exposure to metal-rich particulate pollution is associated with adverse health outcomes. In particular, lead has recently been shown to be toxic in young children even at low levels previously considered 'safe'. Lead poisoning from vehicle pollution has been addressed internationally by removal of leaded petrol but toxic blood lead levels in children continue to be reported in urban areas, the source suggested to be resuspended roadside soil, enriched in lead due to previous leaded fuel usage. Here, we use paired geochemical and magnetic analyses of natural biomonitors—kerbside tree leaves—and of air sample filters to examine contemporary sources of particulate pollution, and show that co-associated, fine (<1 μm) lead- and iron-rich particles are emitted as vehicle-derived pollutants. Higher and strongly correlated lead, iron and magnetic remanence values were found closer to roads and on the road-proximal rather than road-distal sides of trees. Critically, highest pollutant values occurred on tree leaves next to uphill rather than downhill road lanes. The lead content of the leaf particulates was associated only with sub-micrometre, combustion-derived spherical particles. These results indicate that vehicle exhaust emissions, rather than resuspended soil dust, or tyre, brake or other vehicle wear are the major source of the lead, iron and magnetic loadings on roadside tree leaves. Analysis of leaves at different heights showed that leaf particulate lead and iron concentrations are highest at ˜0.3 m (i.e. small child height) and at 1.5-2 m (adult head height) above ground level; monitoring station collectors placed at 3 m above the surface thus significantly under-estimate kerbside, near-surface lead concentrations. These results indicate that vulnerable groups, especially young children, continue to be exposed to fine, lead- and iron-rich, vehicle-derived particulates.

Measuring the healthfulness of food retail stores: variations by store type and neighbourhood deprivation.

PubMed

Black, Christina; Ntani, Georgia; Inskip, Hazel; Cooper, Cyrus; Cummins, Steven; Moon, Graham; Baird, Janis

2014-05-23

The consumer nutrition environment has been conceptualised as in-store environmental factors that influence food shopping habits. More healthful in-store environments could be characterised as those which promote healthful food choices such as selling good quality healthy foods or placing them in prominent locations to prompt purchasing. Research measuring the full-range of in-store environmental factors concurrently is limited. To develop a summary score of 'healthfulness' composed of nine in-store factors that influence food shopping behaviour, and to assess this score by store type and neighbourhood deprivation. A cross-sectional survey of 601 retail food stores, including supermarkets, grocery stores and convenience stores, was completed in Hampshire, United Kingdom between July 2010 and June 2011. The survey measured nine variables (variety, price, quality, promotions, shelf placement, store placement, nutrition information, healthier alternatives and single fruit sale) to assess the healthfulness of retail food stores on seven healthy and five less healthy foods that are markers of diet quality. Four steps were completed to create nine individual variable scores and another three to create an overall score of healthfulness for each store. Analysis of variance showed strong evidence of a difference in overall healthfulness by store type (p < 0.001). Large and premium supermarkets offered the most healthful shopping environments for consumers. Discount supermarkets, 'world', convenience and petrol stores offered less healthful environments to consumers however there was variation across the healthfulness spectrum. No relationship between overall healthfulness and neighbourhood deprivation was observed (p = 0.1). A new composite measure of nine variables that can influence food choices was developed to provide an overall assessment of the healthfulness of retail food stores. This composite score could be useful in future research to measure the relationship between main food store and quality of diet, and to evaluate the effects of multi-component food environment interventions.

Potential environmental impact of bioethanol production chain from fiber sorghum to be used in passenger cars.

PubMed

Forte, Annachiara; Zucaro, Amalia; Fagnano, Massimo; Fierro, Angelo

2017-11-15

A life cycle assessment (LCA) was applied to assess the environmental load of a prospective local bioethanol (EtOH) production system in Southern Italy by using lignocellulosic Fiber sorghum (FS) feedstock. A two steps analysis was carried out considering: (i) a "cradle-to-farm gate" LCA to investigate thoroughly the FS cultivation on hilly marginal land and (ii) a "cradle-to-wheels" system boundary encompassing the environmental pressure of the whole EtOH supply-use chain. Primary data related to lignocellulosic biomass production were combined with experimental feedstock conversion processes through advanced second generation technology. The purpose was the evaluation of the environmental performance of different EtOH-gasoline mixtures in midsize passenger cars: E10 (10% of EtOH and 90% of gasoline) and E85 (85% of EtOH and 15% of gasoline). N fertilization appeared as the prevailing contributor of the crop phase. The "cradle-to-wheels" results concerning E10 passenger car disclosed that the main hotspots were represented by the input of low sulphur petrol (66%) and the linked tailpipe emissions (15%), for almost all the impact categories. Otherwise, for E85 flex-fuel vehicle, the major drivers were represented by the feedstock production (46%) and the imported electricity used in the conversion facility (18%). The FS EtOH blends entailed potential environmental benefits compared with the fossil counterpart (gasoline) for climate change, ozone and fossil depletions. Otherwise, they evidenced a worse profile in terms of acidification, eutrophication and particulate matter formation. Within the context of a the prospective territorial bio-refinery network, the comparison of the annual FS bioethanol based systems with similar EtOH scenarios from giant reed perennial crops highlighted: (i) the importance to optimize the N-management for FS feedstock cultivation and (ii) the need to increase the use of the renewable energy carriers along the industrial conversion pathway. Copyright © 2017 Elsevier B.V. All rights reserved.

Triglycerides, total cholesterol, high density lipoprotein cholesterol and low density lipoprotein cholesterol in rats exposed to premium motor spirit fumes.

PubMed

Aberare, Ogbevire L; Okuonghae, Patrick; Mukoro, Nathaniel; Dirisu, John O; Osazuwa, Favour; Odigie, Elvis; Omoregie, Richard

2011-06-01

Deliberate and regular exposure to premium motor spirit fumes is common and could be a risk factor for liver disease in those who are occupationally exposed. A possible association between premium motor spirit fumes and plasma levels of triglyceride, total cholesterol, high density lipoprotein cholesterol and low density lipoprotein cholesterol using a rodent model could provide new insights in the pathology of diseases where cellular dysfunction is an established risk factor. The aim of this study was to evaluate the possible effect of premium motor spirit fumes on lipids and lipoproteins in workers occupationally exposed to premium motor spirit fumes using rodent model. Twenty-five Wister albino rats (of both sexes) were used for this study between the 4(th) of August and 7(th) of September, 2010. The rats were divided into five groups of five rats each. Group 1 rats were not exposed to premium motor spirit fumes (control group), group 2 rats were exposed for 1 hour daily, group 3 for 3 hours daily, group 4 for 5 hours daily and group 5 for 7 hours daily. The experiment lasted for a period of 4 weeks. Blood samples obtained from all the groups after 4 weeks of exposure were used for the estimation of plasma levels of triglyceride, total cholesterol, high density lipoprotein- cholesterol and low density lipoprotein- cholesterol. Results showed significant increase in means of plasma total cholesterol and low density lipoprotein levels (P<0.05). The mean triglyceride and total body weight were significantly lower (P<0.05) in the exposed group when compared with the unexposed. The plasma level of high density lipoprotein, the ratio of low density lipoprotein to high density lipoprotein and the ratio of total cholesterol to high density lipoprotein did not differ significantly in exposed subjects when compared with the control group. These results showed that frequent exposure to petrol fumes may be highly deleterious to the liver cells.

Reservoir simulation with MUFITS code: Extension for double porosity reservoirs and flows in horizontal wells

NASA Astrophysics Data System (ADS)

Afanasyev, Andrey

2017-04-01

Numerical modelling of multiphase flows in porous medium is necessary in many applications concerning subsurface utilization. An incomplete list of those applications includes oil and gas fields exploration, underground carbon dioxide storage and geothermal energy production. The numerical simulations are conducted using complicated computer programs called reservoir simulators. A robust simulator should include a wide range of modelling options covering various exploration techniques, rock and fluid properties, and geological settings. In this work we present a recent development of new options in MUFITS code [1]. The first option concerns modelling of multiphase flows in double-porosity double-permeability reservoirs. We describe internal representation of reservoir models in MUFITS, which are constructed as a 3D graph of grid blocks, pipe segments, interfaces, etc. In case of double porosity reservoir, two linked nodes of the graph correspond to a grid cell. We simulate the 6th SPE comparative problem [2] and a five-spot geothermal production problem to validate the option. The second option concerns modelling of flows in porous medium coupled with flows in horizontal wells that are represented in the 3D graph as a sequence of pipe segments linked with pipe junctions. The well completions link the pipe segments with reservoir. The hydraulics in the wellbore, i.e. the frictional pressure drop, is calculated in accordance with Haaland's formula. We validate the option against the 7th SPE comparative problem [3]. We acknowledge financial support by the Russian Foundation for Basic Research (project No RFBR-15-31-20585). References [1] Afanasyev, A. MUFITS Reservoir Simulation Software (www.mufits.imec.msu.ru). [2] Firoozabadi A. et al. Sixth SPE Comparative Solution Project: Dual-Porosity Simulators // J. Petrol. Tech. 1990. V.42. N.6. P.710-715. [3] Nghiem L., et al. Seventh SPE Comparative Solution Project: Modelling of Horizontal Wells in Reservoir Simulation // SPE Symp. Res. Sim., 1991. DOI: 10.2118/21221-MS.

Experimental Constraints on Fe Isotope Fractionation in Carbonatite Melt Systems

NASA Astrophysics Data System (ADS)

Stuff, M.; Schuessler, J. A.; Wilke, M.

2015-12-01

Iron isotope data from carbonatite rocks show the largest variability found in igneous rocks to date [1]. Thus, stable Fe isotopes are promising tracers for the interaction of carbonate and silicate magmas in the mantle, particularly because their fractionation is controlled by oxidation state and bonding environment. The interpretation of Fe isotope data from carbonatite rocks remains hampered, since Fe isotope fractionation factors between silicate and carbonate melts are unknown and inter-mineral fractionation can currently only be assessed by theoretical calculations [1;2]. We present results from equilibration experiments in three natrocarbonatite systems between immiscible silicate and carbonate melts, performed at 1200°C and 0.7 GPa in an internally heated gas pressure vessel at intrinsic redox conditions. The Fe isotope compositions of the silicate melt (sil.m.), quenched to a glass, and the carbonate melt (carb.m.), forming fine-grained quench crystals, were analysed by solution MC-ICP-MS. Our first data indicate a remarkable fractionation of Δ56Fesil.m.‒carb.m.= 0.29 ±0.07 ‰ near equilibrium. At short run durations, even stronger fractionation up to Δ56Fesil.m.‒carb.m. = 0.41 ±0.07 ‰ occurs, due to kinetic effects. Additionally, Δ56Fesil.m.‒carb.m. changes with bulk chemical composition, likely reflecting considerable differences between the studied systems in terms of the Fe3+/Fe2+-ratios in the two immiscible liquids. Our findings provide experimental support for a carbonatite genesis model, in which extremely negative δ56Fe values in carbonatites result from differentiation processes, such as liquid immiscibility [1]. This effect can be enhanced by disequilibrium during fast ascent of carbonatite magmas. Their sensitivity to chemical and redox composition makes Fe isotopes a potential tool for constraining the original compositions of carbonatite magmas. [1] Johnson et al. (2010) Miner. Petrol. 98, 91-110. [2] Polyakov & Mineev (2000) Geochim. Cosmochim. Acta 64, 849-865.

Analysis and experimental investigation of ceramic powder coating on aluminium piston

NASA Astrophysics Data System (ADS)

Pal, S.; Deore, A.; Choudhary, A.; Madhwani, V.; Vijapuri, D.

2017-11-01

Energy conservation and efficiency have always been the quest of engineers concerned with internal combustion engines. The diesel engine generally offers better fuel economy than its counterpart petrol engine. Even the diesel engine rejects about two thirds of the heat energy of the fuel, one-third to the coolant, and one third to the exhaust, leaving only about one-third as useful power output. Theoretically if the heat rejected could be reduced, then the thermal efficiency would be improved, at least up to the limit set by the second law of thermodynamics. Low Heat Rejection engines aim to do this by reducing the heat lost to the coolant. Thermal Barrier Coatings (TBCs) in diesel engines lead to advantages including higher power density, fuel efficiency, and multifuel capacity due to higher combustion chamber temperature. Using TBC can increase engine power by 8%, decrease the specific fuel consumption by 15-20% and increase the exhaust gas temperature by 200K. Although several systems have been used as TBC for different purposes, yttria stabilized zirconia with 7-8 wt.% yttria has received the most attention. Several factors playing important role in TBC life include thermal conductivity, thermo chemical stability at the service temperature, high thermo mechanical stability to the maximum service temperature and thermal expansion coefficient (TEC). This work mainly concentrates on the behaviour of three TBC powders under the same diesel engine conditions. This work finds out the best powder among yttria, alumina and zirconia to be used as a piston coating material i.e., the one resulting in lowest heat flux and low side skirt and bottom temperature has been chosen for the coating purpose. This work then analyses the coated sample for its surface properties such as hardness, roughness, corrosion resistance and microstructural study. This work aims at making it easier for the manufacturers choose the coating material for engine coating purposes and surface properties for operating them in their service period.

Comparative tissue distribution of metals in birds in Sweden using ICP-MS and laser ablation ICP-MS.

PubMed

Ek, Kristine H; Morrison, Gregory M; Lindberg, Peter; Rauch, Sébastien

2004-08-01

Cadmium, copper, lead, palladium, platinum, rhodium, and zinc profiles were investigated along feather shafts of raptor and other bird species by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The distribution of external versus internal metal contamination of feathers was investigated. The species examined were peregrine falcon (Falco peregrinus), sparrowhawk ( Accipiter nisus), willow grouse (Lagopus lagopus), and house sparrow (Passer domesticus) in Sweden. For habitat comparisons, total Cu, Pb, Zn, and Cd concentrations were analyzed by ICP-MS in feathers of the examined species as well as captive peregrine falcon. For investigation of metal distribution and correlation in different biological materials of raptors, total concentrations of Cu, Pb, Cd, and Zn were also investigated by ICP-MS in feathers, eggs, blood, feces, liver, and kidney of wild peregrine falcon from southwestern Sweden. Laser ablation of feathers revealed that Pb contamination is both external and internal, Zn contamination is internal, and Cd and Cu contamination is predominantly internal, with a few externally attached particles of high concentration. Pb, Cu, and Cd signal intensities were highest in urban habitats and contamination was mainly external in feathers. The background signal intensity of Zn was also higher in birds from urban habitats. The laser ablation profile of PGE (Pt, Pd, Rh) demonstrated that PGE contamination of feathers consists almost exclusively of externally attached PGE-containing particles, with little evidence of internally deposited PGE.Generally, total metal concentrations in feathers were highest in sparrowhawk and house sparrow due to their urban habitat. Total Cu, Zn, and Cd concentrations were highest in liver and kidney due to binding to metallothionein, while the total Pb concentration was highest in feces due to the high excretion rate of Pb. A decreasing temporal trend for Pb in feathers, showing that Pb levels in feathers have decreased since the introduction of nonleaded petrol, is also discussed.

Prediction of PM 10 concentrations at urban traffic intersections using semi-empirical box modelling with instantaneous velocity and acceleration

NASA Astrophysics Data System (ADS)

He, Hong-di; Lu, Wei-Zhen; Xue, Yu

2009-12-01

At urban traffic intersections, vehicles frequently stop with idling engines during the red-light period and speed up rapidly during the green-light period. The changes of driving patterns (i.e., idle, acceleration, deceleration and cruising patterns) generally produce uncertain emission. Additionally, the movement of pedestrians and the influence of wind further result in the random dispersion of pollutants. It is, therefore, too complex to simulate the effects of such dynamics on the resulting emission using conventional deterministic causal models. For this reason, a modified semi-empirical box model for predicting the PM 10 concentrations on roadsides is proposed in this paper. The model constitutes three parts, i.e., traffic, emission and dispersion components. The traffic component is developed using a generalized force traffic model to obtain the instantaneous velocity and acceleration when vehicles move through intersections. Hence the distribution of vehicle emission in street canyon during the green-light period is calculated. Then the dispersion component is investigated using a semi-empirical box model combining average wind speed, box height and background concentrations. With these considerations, the proposed model is applied and evaluated using measured data at a busy traffic intersection in Mong Kok, Hong Kong. In order to test the performance of the model, two situations, i.e., the data sets within a sunny day and between two sunny days, were selected to examine the model performance. The predicted values are generally well coincident with the observed data during different time slots except several values are overestimated or underestimated. Moreover, two types of vehicles, i.e., buses and petrol cars, are separately taken into account in the study. Buses are verified to contribute most to the emission in street canyons, which may be useful in evaluating the impact of vehicle emissions on the ambient air quality when there is a significant change in a specific vehicular population.

The role of total fats, saturated/unsaturated fatty acids and cholesterol content in chicken meat as cardiovascular risk factors.

PubMed

Milićević, Dragan; Vranić, Danijela; Mašić, Zoran; Parunović, Nenad; Trbović, Dejana; Nedeljković-Trailović, Jelena; Petrović, Zoran

2014-03-03

The objective of the study was to present information about the chemical composition, the fatty acids profile, and cholesterol content of chicken meat in order to investigate the impact of chicken meat consumption on cardiovascular risk in the general population. A total of 48 6-wk-old broiler chickens broilers from two farms in June to November of 2012, and February of 2013, were used in this trial. Total lipid content was determined by extraction of fat by petrol ether (Soxhlet) after acid hydrolysis of samples. Fatty acids were determined by capillary gas chromatography. Cholesterol determination was performed by using HPLC/PDA system. The results indicate that the total free cholesterol content in raw breast and drumstick of chickens was in the range of 37,41-79,9 mg/100 g and 48,35-99,5 mg/100 g, respectively. The main fatty acids identified in all cuts were C18:1c9, C18:2n6, C16:0, C18:0, and C16:1. Decreasing the dietary n-6/n-3 clearly decreased the content in breast and drumstick muscle of C18:2n6, C18:3n3, and C20: 3n6, but increased that of C16:0, C18:0, and C20:2. Also, the major saturated fatty acid (SFA) (C16:0 and C18:0) was significantly differ among the four treatments. Our study shows that dietary fat and fatty acid composition influence the concentrations of total cholesterol content, total fat content, and fatty acid composition in broiler muscle. This information will aid in determining the burden of chicken meat as a cardiovascular risk factors disease and act as a planning tool for public-health Programmes.

Organic aerosol source apportionment in London 2013 with ME-2: exploring the solution space with annual and seasonal analysis

NASA Astrophysics Data System (ADS)

Reyes-Villegas, Ernesto; Green, David C.; Priestman, Max; Canonaco, Francesco; Coe, Hugh; Prévôt, André S. H.; Allan, James D.

2016-12-01

The multilinear engine (ME-2) factorization tool is being widely used following the recent development of the Source Finder (SoFi) interface at the Paul Scherrer Institute. However, the success of this tool, when using the a value approach, largely depends on the inputs (i.e. target profiles) applied as well as the experience of the user. A strategy to explore the solution space is proposed, in which the solution that best describes the organic aerosol (OA) sources is determined according to the systematic application of predefined statistical tests. This includes trilinear regression, which proves to be a useful tool for comparing different ME-2 solutions. Aerosol Chemical Speciation Monitor (ACSM) measurements were carried out at the urban background site of North Kensington, London from March to December 2013, where for the first time the behaviour of OA sources and their possible environmental implications were studied using an ACSM. Five OA sources were identified: biomass burning OA (BBOA), hydrocarbon-like OA (HOA), cooking OA (COA), semivolatile oxygenated OA (SVOOA) and low-volatility oxygenated OA (LVOOA). ME-2 analysis of the seasonal data sets (spring, summer and autumn) showed a higher variability in the OA sources that was not detected in the combined March-December data set; this variability was explored with the triangle plots f44 : f43 f44 : f60, in which a high variation of SVOOA relative to LVOOA was observed in the f44 : f43 analysis. Hence, it was possible to conclude that, when performing source apportionment to long-term measurements, important information may be lost and this analysis should be done to short periods of time, such as seasonally. Further analysis on the atmospheric implications of these OA sources was carried out, identifying evidence of the possible contribution of heavy-duty diesel vehicles to air pollution during weekdays compared to those fuelled by petrol.

The role of total fats, saturated/unsaturated fatty acids and cholesterol content in chicken meat as cardiovascular risk factors

PubMed Central

2014-01-01

Background The objective of the study was to present information about the chemical composition, the fatty acids profile, and cholesterol content of chicken meat in order to investigate the impact of chicken meat consumption on cardiovascular risk in the general population. Methods A total of 48 6-wk-old broiler chickens broilers from two farms in June to November of 2012, and February of 2013, were used in this trial. Total lipid content was determined by extraction of fat by petrol ether (Soxhlet) after acid hydrolysis of samples. Fatty acids were determined by capillary gas chromatography. Cholesterol determination was performed by using HPLC/PDA system. Results The results indicate that the total free cholesterol content in raw breast and drumstick of chickens was in the range of 37,41–79,9 mg/100 g and 48,35-99,5 mg/100 g, respectively. The main fatty acids identified in all cuts were C18:1c9, C18:2n6, C16:0, C18:0, and C16:1. Decreasing the dietary n-6/n-3 clearly decreased the content in breast and drumstick muscle of C18:2n6, C18:3n3, and C20: 3n6, but increased that of C16:0, C18:0, and C20:2. Also, the major saturated fatty acid (SFA) (C16:0 and C18:0) was significantly differ among the four treatments. Conclusion Our study shows that dietary fat and fatty acid composition influence the concentrations of total cholesterol content, total fat content, and fatty acid composition in broiler muscle. This information will aid in determining the burden of chicken meat as a cardiovascular risk factors disease and act as a planning tool for public-health Programmes. PMID:24588940

Assessing the sources and bioaccessibility of Lead in Soils from London

NASA Astrophysics Data System (ADS)

Cave, Mark R.; Wragg, Joanna; Chenery, Simon

2013-04-01

The lead content of soil is important since it is toxic to humans and particularly because children tend to more readily absorb lead than do adults: children absorb up to 40% into the bloodstream from ingested or inhaled lead, versus 5-15% in adults. Studies have shown that relatively low concentrations of lead in blood can lead to significant decrease in IQ of children (e.g. Jakubowski, 2011) leading to neuropathy and hypertension in adults. The British Geological Survey has recently completed a systematic high-density geochemical soil survey of the Greater London Area (GLA) in which over 6000 surface soil samples were collected and analysed for 50 elements. The Pb content of the soils range from 11 mg/kg to greater than 10000 mg/kg with mean and median values of 301 and 185 mg/kg, respectively. The ingestion bioaccessible fraction of Pb was measured using an in-vitro bioaccessibility test showing that 68% of the total Pb in London soils is bioaccessible. Measurement of Pb isotopic ratios in selected soils matched with those found in London air particulates and, to a lesser extent, with petrol lead. Self modelling mixture resolution of the 50 element geochemical data set was used to identify geochemically distinct components in the data with Pb being associated with 11 of the components which were of both natural and anthropogenic origin. Relationships between the soil components, the bioaccessible fraction and the Pb isotope ratios provided an indication of the sources of mobile lead in the London soils. References JAKUBOWSKI, M. 2011. Low-level environmental lead exposure and intellectual impairment in children - the current concepts of risk assessment. International Journal of Occupational Medicine and Environmental Health, Vol. 24, 1-7. APPLETON, J D, CAVE, M R, and WRAGG, J. 2012. Modelling lead bioaccessibility in urban topsoils based on data from Glasgow, London, Northampton and Swansea, UK. Environmental Pollution, Vol. 171, 265-272.

Context and characteristics of illicit drug use in coastal and interior Tanzania.

PubMed

Tiberio, Jenny; Laurent, Yovin Ivo; Ndayongeje, Joel; Msami, Amani; Welty, Susie; Ngonyani, Alois; Mwankemwa, Syangu; Makumbuli, Moza; McFarland, Willi; Morris, Meghan D

2018-01-01

An increase in heroin seizures in East Africa may signal wider local consumption of illicit drugs. Most information about drug use in Tanzania is from the economic capital, Dar es Salaam, and well-travelled Zanzibar. More data are needed on the extent, trends, and characteristics of illicit drug use in the vast coast and interior of the country. The study was a rapid assessment, triangulating data from in-depth interviews of primary key informants (people who use drugs [PWUD]), secondary informants (police, community members, service providers), and ethnographic mapping of hotspots in 12 regions of Tanzania. We conducted 436 in-depth interviews from September 2013 to August 2014. Regions were categorized as (1) nascent: drug use is beginning to take root; (2) established: drug use has existed for some time; or (3) pervasive: drug use is spreading into new sub-groups/areas. Multiple sources corroborated that illicit drug use has been increasing in all regions. Most PWUD worked in the cash economy as bus touts, labourers, fishermen, miners, or sex workers, or stole to survive or support their habit. PWUD congregated around bus stops along transit corridors, in abandoned buildings, and in low-income residential areas. Informants described less visible PWUD among military, police, and working-class people. Cannabis was the most common, smoked alone or with tobacco and heroin ("cocktail"). Heroin was available in all regions. Cocaine was less common, likely due to high price and variable availability. Substances such as petrol, shoe polish, and glue were used as inhalants. Illicit drug use is widespread with variable features beyond cosmopolitan areas of Tanzania. Improving transportation infrastructure and economic opportunities combined with poverty and inequality appear key factors for increasing use. Findings call attention to increasing and widening drug use in Tanzania and the need to plan prevention, treatment, and harm-reduction measures nationally. Copyright © 2017 Elsevier B.V. All rights reserved.

Towards innovative roadside monitoring

NASA Astrophysics Data System (ADS)

Ojha, G.; Appel, E.; Magiera, T.

2012-04-01

Soil contamination along roadsides is an important factor of anthropogenic point source pollution. Climatic and traffic-specific factors influence the amount and characteristics of pollution emitted and deposited in the roadside soil. In our present study we focus on monitoring typical traffic pollutants (heavy metals HM, platinum group elements, polycyclic hydrocarbons PAH), and investigate the use of magnetic parameters, especially magnetic susceptibility (MS) as proxy. Monitoring plots were installed along roadside in areas with different climatic conditions and different traffic-specific activities (traffic density and speed, vehicle types, abrasion of tires, brake linings, petrol/diesel compounds and road maintenance). For monitoring we removed 10-15 cm of top soil at 1 m distance from the roadside edge and placed 30 plastic boxes there filled with clean quartz sand, to be sampled after regular intervals within two years. Preliminary data from the first year of monitoring are presented. Magnetic results revealed that a coarse grained magnetite-like phase is responsible for the enhancement of magnetic concentration. The mass-specific MS and concentration of pollutants (HM, PAH) all show a significant increase with time, however, there are obviously also seasonal and site-dependent effects which lead to more stable values over several months or even some decrease in the upper few cm due to migration into depth. Source identification indicates that the accumulated PAHs are primarily emissions from traffic. In order to be able to discriminate in between different kinds of transport and deposition (surface run off from the road and neighbouring soil material, splash water, air transport), we additionally established pillars at the roadside with clean quartz sampling boxes at different heights (surface, 0.5 m, 2 m). As a first surprising result we observed that the increase in the boxes at surface is not necessarily higher than at 0.5 m height. The results from our monitoring studies will be utilized to understand site-specific characteristics and to develop new innovative roadside pollution monitoring concepts.

Recent Extreme Marine Events at Southern Coast of Black Sea

NASA Astrophysics Data System (ADS)

Ozyurt Tarakcioglu, Gulizar; Cevdet Yalciner, Ahmet; Kirezci, Cagil; Baykal, Cuneyt; Gokhan Guler, Hasan; Erol, Onur; Zaytsev, Andrey; Kurkin, Andrey

2015-04-01

The utilization at the coastal areas of Black Sea basin has increased in the recent years with the projects such as large commercial ports, international transportation hubs, gas and petrol pipelines, touristic and recreational infrastructures both along surrounding shoreline. Although Black Sea is a closed basin, extreme storms and storm surges have also been observed with an increasing frequency in the recent years. Among those events, February 1999, March 2013 and September 2014 storms impacted Southern coast of Black sea have clearly shown that the increasing economic value at the coastal areas caused the increasing cost of damages and loss of property by natural hazards. The storm occurred on February 19-20, 1999 is one of the most destructive storm in the last decades. The 1999 event (1999 Southern Black sea storm) caused destruction at all harbors and coastal protection structures along the Black Sea coast of Turkey. The complete damage of the breakwater of Giresun Harbor and damage on the harbor structures and cargo handling equipment were the major impacts of the 1999 Southern Black sea storm. Similar coastal impact have also been observed during the September 24, 2014 storm at 500m East of Giresun harbor. Although there are considerable number of destructive storms observed at southern coast of Black sea recently, data on these events are limited and vastly scattered. In this study the list of recent extreme marine events at South coast of the Black sea compiled and related data such as wind speed, wave height, period, and type of damages are cataloged. Particular attention is focused on the 1999 and 2014 storm events. The meteorological and morphological characteristics which may be considered as the reasons of the generation and coastal amplification of these storms are discussed. ACKNOWLEDGEMENTS: This study is partly supported by Turkish Russian Joint Research Grant Program by TUBITAK (Turkey) and RFBR (Russia), and TUBITAK 213M534 Research Project.

Investigating the Mantle Source of the Lunar Crater Volcanic Field, Nevada: Evidence of a Thermal Plume?

NASA Astrophysics Data System (ADS)

Lee, J. W.; Roden, M.

2016-12-01

The Easy Chair Crater (ECC), located within the Lunar Crater Volcanic Field (LCVF) in central Nevada is particularly interesting because of the unusually high equilibrium temperatures and strain recorded by the mantle-derived xenoliths at LCVF1. In addition, a gravity and elevation anomaly suggests the possibility of an underlying thermal plume in the region2. In order to determine if the rocks at ECC are geochemically similar to rocks from other plume-related regions, we analyzed melt inclusions and olivine phenocrysts collected from basalts near the crater. Chlorine amounts in melt inclusions were normalized to the highly incompatible K to produce a ratio that is insensitive to crystallization within or along the walls of the inclusion3. Because Cl is implicated in lithosphere recycling, the Cl/K ratio can be used to differentiate magmatic source components. Initial results (Fig. 1) indicate that basalts from ECC are geochemically more similar to ocean island basalts than to MORB or arc basalts. Elemental ratios in olivine phenocrysts from basaltic magmas can be used to determine the petrology of the source rock for particular silicate melts. In turn, petrology of mantle sources is thought to correlate with source nature (e.g., plume versus upper mantle)4. Specifically, Ni and Mn amounts were evaluated in order to determine if magma sources were pyroxenite-rich. Preliminary calculations of the wt. fraction of pyroxenite in the source of ECC basalts ranged from 0.13 to 0.68 indicating the possibility of a significant amount of pyroxenite in the magmatic source which would be expected if a plume was present beneath LCVF. References:1Smith, D. (2000) JGR 105: 16769; 2Saltus, R.W. & Thompson, G.A. (1995) Tectonics 14:1235; 3Patiño Douce, A.E. & Roden, M.F. (2006) Geochim Cosmochim Acta 70: 3173; 4Gurenko et al. (2010) Contrib Mineral Petrol 159: 689

Public health impacts of city policies to reduce climate change: findings from the URGENCHE EU-China project.

PubMed

Sabel, Clive E; Hiscock, Rosemary; Asikainen, Arja; Bi, Jun; Depledge, Mike; van den Elshout, Sef; Friedrich, Rainer; Huang, Ganlin; Hurley, Fintan; Jantunen, Matti; Karakitsios, Spyros P; Keuken, Menno; Kingham, Simon; Kontoroupis, Periklis; Kuenzli, Nino; Liu, Miaomiao; Martuzzi, Marco; Morton, Katie; Mudu, Pierpaolo; Niittynen, Marjo; Perez, Laura; Sarigiannis, Denis; Stahl-Timmins, Will; Tobollik, Myriam; Tuomisto, Jouni; Willers, Saskia

2016-03-08

Climate change is a global threat to health and wellbeing. Here we provide findings of an international research project investigating the health and wellbeing impacts of policies to reduce greenhouse gas emissions in urban environments. Five European and two Chinese city authorities and partner academic organisations formed the project consortium. The methodology involved modelling the impact of adopted urban climate-change mitigation transport, buildings and energy policy scenarios, usually for the year 2020 and comparing them with business as usual (BAU) scenarios (where policies had not been adopted). Carbon dioxide emissions, health impacting exposures (air pollution, noise and physical activity), health (cardiovascular, respiratory, cancer and leukaemia) and wellbeing (including noise related wellbeing, overall wellbeing, economic wellbeing and inequalities) were modelled. The scenarios were developed from corresponding known levels in 2010 and pre-existing exposure response functions. Additionally there were literature reviews, three longitudinal observational studies and two cross sectional surveys. There are four key findings. Firstly introduction of electric cars may confer some small health benefits but it would be unwise for a city to invest in electric vehicles unless their power generation fuel mix generates fewer emissions than petrol and diesel. Second, adopting policies to reduce private car use may have benefits for carbon dioxide reduction and positive health impacts through reduced noise and increased physical activity. Third, the benefits of carbon dioxide reduction from increasing housing efficiency are likely to be minor and co-benefits for health and wellbeing are dependent on good air exchange. Fourthly, although heating dwellings by in-home biomass burning may reduce carbon dioxide emissions, consequences for health and wellbeing were negative with the technology in use in the cities studied. The climate-change reduction policies reduced CO2 emissions (the most common greenhouse gas) from cities but impact on global emissions of CO2 would be more limited due to some displacement of emissions. The health and wellbeing impacts varied and were often limited reflecting existing relatively high quality of life and environmental standards in most of the participating cities; the greatest potential for future health benefit occurs in less developed or developing countries.

Source Estimation of Wintertime Soot Particles for an Urban Site Varanasi (25.30 N, 83.00 E) in Central Indo-Gangetic Plain Region

NASA Astrophysics Data System (ADS)

Singh, A. K.; Srivastava, M. K.; Dumka, U. C.; Singh, R. K.; Singh, R. S.; Tiwari, S.; Mehrotra, B. J.; Srivastava, A. K.

2017-12-01

Black carbon particles (BC: also called Soot) are formed by incomplete combustion of hydrocarbon based fuels (fossil fuel: coal, diesel, petrol, etc.) as well as due to burning of biomass and bio-fuels (wood, shrubs, dry leaves, etc.). Soot particles are warming agent to the atmosphere that gained wide attention in recent years due to their direct and indirect impacts on local, regional as well as global climate. The climatic effects due to soot are not well understood as indicated by large uncertainties in their climate forcing estimation, particularly in South and East Asian region, possibly due to unavailability of adequate database and information about the source. Measurement of wintertime BC mass concentrations for urban site in central IGP, `Varanasi' (25.30 N, 83.00 E), using a seven wavelength Aethalometer is reported in this work. Delta-C (=BC370 - BC880), which is an indicator of biomass/bio-fuels or residential coal burning is used to understand the source. Aethalometer based source apportionment model "Aethalometer model" was used to apportion the fossil fuel/traffic and wood/biomass burning mass concentration to the total BC mass. The preliminary results for representative month (January-2015) show that daily-average BC mass ranged from 4.47 to 20.70 μg m-3 (Average: 9.45 ± 4.15 μg m-3). The daily Absorption Ångström Exponent (AAE) and the ratio of BCff/BC and BCff/BCwb varied between 1.09 - 1.32, 0.67 - 0.92 and 2 - 40, respectively, due to the changes in BC emissions rates. The total BC, BC from fossil fuel (BCff) and BC from wood/biomass burning (BCwb) behaved in the remarkable diurnal pattern, behaving opposite to the mixing layer heights (MLHs). During daytime, MLHs are higher due to surface based solar warming and causes more volume of atmosphere for the BC dispersion. This phenomenon causes the surface measurement of lower BC mass during the daytime. The data is, however, still being processed for multi-year wintertime observations and the detailed discussions will be shown during the presentation.

Fiscal instruments for regulating the sustainable development of urban transport systems in Russia

NASA Astrophysics Data System (ADS)

Mayburov, I.; Leontyeva, Y.

2017-06-01

The article explains the role of public transport pricing. It proves the need for a systemic approach to building a modern public transit system. The authors argue that the main objective of the approach should be to reduce the use of private vehicles in the urban environment and increasing public transport use. It is proven that for the consumer of transport services the price per trip is an important factor when deciding whether to travel by car or by public transport. The authors analyze the available literature assessing the effects of widespread car ownership on users of the city transit system. Conflict situations that occur due to the unabated desire of city residents to travel by car are analyzed. A research method is proposed. It is shown that public transport fares have been growing in Russia at an accelerated pace when compared to the overall increase in prices of all goods and services, including motor vehicles, petrol and oils. The fare growth has resulted in a 3.6 fold drop in demand for public transport services over the 15 years being analyzed. Over the same period, the number of privately owned cars grew 120 percent. A conclusion is drawn that regular fare hikes have encouraged urban population to gradually opt against travelling by public transport. That resulted in higher demand for car travel and, eventually, in an accelerated growth in car usage. One can conclude that a persistent institutional trap has taken shape in Russian metropolises. Essentially, it means that higher public transport fares have led to lower demand for public transit services. As ridership goes down, public transport operators have to again increase prices, thus driving the demand for their services down. It is proven that escaping the trap will require restoring the ratio of prices to make sure that the price charged for a public transport trip is far lower than the cost of travelling by car. The aim of this study is to assess the influence of the factor of public transport fares on demand for private car usage and public transport ridership.

Basanite-nephelinite suite from early Kilauea: Carbonated melts of phlogopite-garnet peridotite at Hawaii's leading magmatic edge

USGS Publications Warehouse

Sisson, T.W.; Kimura, Jun-Ichi; Coombs, M.L.

2009-01-01

A basanite-nephelinite glass suite from early submarine Kilauea defines a continuous compositional array marked by increasing concentrations of incompatible components with decreasing SiO2, MgO, and Al2O3. Like peripheral and post-shield strongly alkalic Hawaiian localities (Clague et al. in J Volcanol Geotherm Res 151:279-307, 2006; Dixon et al. in J Pet 38:911-939, 1997), the early Kilauea basanite-nephelinite glasses are interpreted as olivine fractionation products from primary magnesian alkalic liquids. For early Kilauea, these were saturated with a garnet-phlogopite-sulfide peridotite assemblage, with elevated dissolved CO2 contents responsible for the liquids' distinctly low-SiO2 concentrations. Reconstructed primitive liquids for early Kilauea and other Hawaiian strongly alkalic localities are similar to experimental 3 GPa low-degree melts of moderately carbonated garnet lherzolite, and estimated parent magma temperatures of 1,350-1,400??C (olivine-liquid geothermometry) match the ambient upper mantle geotherm shortly beneath the base of the lithosphere. The ???3 GPa source regions were too hot for stable crystalline carbonate and may have consisted of ambient upper mantle peridotite containing interstitial carbonate-silicate or carbonatitic liquid, possibly (Dixon et al. in Geochem Geophys Geosyst 9(9):Q09005, 2008), although not necessarily, from the Hawaiian mantle plume. Carbonate-enriched domains were particularly susceptible to further melting upon modest decompression during upward lithospheric flexure beneath the advancing Hawaiian Arch, or by conductive heating or upward drag by the Hawaiian mantle plume. The early Kilauea basanite-nephelinite suite has a HIMU-influenced isotopic character unlike other Hawaiian magmas (Shimizu et al. in EOS Tran Amer Geophys Union 82(47): abstr V12B-0962, 2001; Shimizu et al. in Geochim Cosmochim Acta 66(15A):710, 2002) but consistent with oceanic carbonatite involvement (Hoernle et al. in Contrib Mineral Petrol 142:520-542, 2002). It may represent the melting products of a fertile domain in the ambient upper mantle impinged upon and perturbed by the sustained plume source that feeds later shield-stage magmatism. ?? US Government 2009.

Bioethanol from poplar clone Imola: an environmentally viable alternative to fossil fuel?

PubMed

Guo, Miao; Li, Changsheng; Facciotto, Gianni; Bergante, Sara; Bhatia, Rakesh; Comolli, Roberto; Ferré, Chiara; Murphy, Richard

2015-01-01

Environmental issues, e.g. climate change, fossil resource depletion have triggered ambitious national/regional policies to develop biofuel and bioenergy roles within the overall energy portfolio to achieve decarbonising the global economy and increase energy security. With the 10 % binding target for the transport sector, the Renewable Energy Directive confirms the EU's commitment to renewable transport fuels especially advanced biofuels. Imola is an elite poplar clone crossed from Populus deltoides Bartr. and Populus nigra L. by Research Units for Intensive Wood Production, Agriculture Research Council in Italy. This study examines its suitability for plantation cultivation under short or very short rotation coppice regimes as a potential lignocellulosic feedstock for the production of ethanol as a transport biofuel. A life cycle assessment (LCA) approach was used to model the cradle-to-gate environmental profile of Imola-derived biofuel benchmarked against conventional fossil gasoline. Specific attention was given to analysing the agroecosystem fluxes of carbon and nitrogen occurring in the cultivation of the Imola biomass in the biofuel life cycle using a process-oriented biogeochemistry model (DeNitrification-DeComposition) specifically modified for application to 2G perennial bioenergy crops and carbon and nitrogen cycling. Our results demonstrate that carbon and nitrogen cycling in perennial crop-soil ecosystems such as this example can be expected to have significant effects on the overall environmental profiles of 2G biofuels. In particular, soil carbon accumulation in perennial biomass plantations is likely to be a significant component in the overall greenhouse gas balance of future biofuel and other biorefinery products and warrants ongoing research and data collection for LCA models. We conclude that bioethanol produced from Imola represents a promising alternative transport fuel offering some savings ranging from 35 to 100 % over petrol in global warming potential, ozone depletion and photochemical oxidation impact categories. Via comparative analyses for Imola-derived bioethanol across potential supply chains, we highlight priority issues for potential improvement in 2G biofuel profiling. Advanced clones of poplar such as Imola for 2G biofuel production in Italy as modelled here show potential to deliver an environmentally sustainable lignocellulosic biorefinery industry and accelerate advanced biofuel penetration in the transport sector.

Risky behavior of drivers of motorized two wheeled vehicles in India.

PubMed

Dandona, Rakhi; Kumar, G Anil; Dandona, Lalit

2006-01-01

Motorized two-wheeled vehicles (MTV) account for a large proportion of road traffic in India and the riders of these vehicles have a high risk of road traffic injuries. We report on the availability of drivers licenses, use of a helmet, driver behavior, and condition of vehicles for MTV drivers in Hyderabad, a city in India Drivers of a MTV aged >16 years were interviewed at petrol filling stations There were 4,183 MTV drivers who participated in the study. Four hundred sixty one (11%; 95% CI 9.7-12.3%) drivers had not obtained a drivers license and 798 (21.4%) had obtained a license without taking the mandatory driving test. Two thousand nine hundred twenty (69.8%; 95% CI 67.9-71.7%) drivers reported no/very occasional use of a helmet, the significant predictors of which included that those driving borrowed a MTV (odds ratio 7.90; 95% CI 3.40-18.40) or driving moped/scooterette/scooter as compared with motorcycle (3.32; 2.76-3.98), lower education (3.10; 2.66-3.61), age >45 years (2.41; 1.63-3.57), and males (1.57; 1.16-2.13). Two thousand five hundred and eight (59.9%) drivers reported committing a traffic law violation at least once within the last 3 months. Overall, 1,222 (29.2%) drivers reported ever being caught by traffic police for a traffic law violation with data on violations available for 1,205 of these drivers, of whom 680 (56.4%) paid a fine, 310 (25.7%) paid by bribe, and 215 (17.8%) made no payment. The proportion of those who did not make payment for committed violation was significantly higher among females (46.8%) than males (16.3%). Two thousand fifty two (49%) of all MTVs had no rearview mirror These data suggest the need to enact and enforce policy interventions for improving the drivers license system, mandatory use of a helmet, effective traffic law enforcement, and ensuring good vehicle condition to reduce the risk factors that potentially contribute to mortality and morbidity in road traffic crashes in MTV drivers in Indian cities.

Prevalence and issues in non-use of safety belts and child restraints in a high-income developing country: lessons for the future.

PubMed

Barss, Peter; Al-Obthani, Murad; Al-Hammadi, Abdulla; Al-Shamsi, Hamad; El-Sadig, Mohammed; Grivna, Michal

2008-01-01

In United Arab Emirates (UAE), a high-income developing country, safety belt (SB) legislation was implemented in 1998, covering only front-seated adults on highways outside cities. We assessed wearing of SBs after 5 years, together with use of safety restraints by rear passengers and children, perceptions about SBs, and use of tinted glass. A cross-sectional survey in 2003-2004 in Al Ain, population 400,000 and the main desert city of UAE, used random sampling of petrol stations; about 80% of UAE's population is non-citizens. Five of 30 stations were selected, including 3 different speed zones; vehicles with children were over-sampled. Drivers were interviewed by questionnaire. Use of safety restraints and presence of tinted glass were verified by observation. Confounding and correlation were assessed by stratification and logistic regression. The sample included 500 vehicles, containing 959 adults and 876 children; 382 vehicles had children. SBs were used by 29% of drivers, 14% of front-seat and 2% of rear-seat adult passengers. 23% of children were in front; only 4% in front and 1% in the rear were restrained. SBs were worn by only 11% of UAE-citizen drivers and 10% of off-duty police and military. Odds ratio for non-use by citizens was 3.55 (95% CI 1.96-6.42). Use was greater among older drivers (p < 0.0005, X(2) trend). Reasons for non-use of SBs included discomfort 42%, forgetfulness 25%, uselessness 17%, carelessness 13%, and dangerous 3%. Among citizens, 15% believed SBs are dangerous. Tinted glass was present in 68% of vehicles. SB legislation failed to protect the population, with low use of restraints by citizens, military, and police, and virtually none among children and rear passengers. Lessons include the necessity of drafting laws that provide comprehensive and effective protection, study of cultural constraints to compliance with injury prevention measures, and locally effective interventions to prepare citizens and enforcers for the expected new behaviour. Highly tinted glass is widespread and poses a barrier to enforcement.

Osmium and lead isotope investigation of magmas within the long-lived Pichincha Volcanic complex from the Northern Andean Volcanic zone (Ecuador)

NASA Astrophysics Data System (ADS)

Gannoun, A.; Samaniego, P.; Martin, H.; Schiano, P.; Hidalgo, S.; Nauret, F.; Le Pennec, J. L.

2015-12-01

The study of arc magmas most often stumbles on deciphering both the nature and the composition of the subduction components involved in magma genesis. In Ecuador, the subduction of the Carnegie ridge, appears as a key parameter accounting for the temporal chemical changes highlighted in the quaternary lavas, whose composition shifted from calc-alkaline to adakitic [1-3]. Moreover, the adakitic signature is only observed in an area located above the Carnegie ridge subduction [4, 5]. Re-Os and Pb isotopic compositions of lavas from the Pichincha volcano were investigated, in order to document the nature and origin of this transition. The Pichincha Volcanic Complex consists of (1) an ancient, eroded edifice (the Rucu, 1.1-0.15 Ma), and (2) a younger edifice (Guagua, 60-11 ka). This structural evolution is correlated with significant variations of trace element abundances, mainly reflecting major processes of magmatic mixtures [1, 2]. In addition to Pichincha lavas, we also analysed the subducted oceanic basalts and sediments (Amadeus campaign), as well as samples of the Pichincha basement. In a 187Os/188Os vs. 1/Os diagram, Pichincha basalts define a positive trend ranging between an unradiogenic Os component (i.e., peridotitic mantle) and a radiogenic basaltic Os component with low Os content, which is consistent with Carnegie ridge basalt composition. On another hand, the sediments and basement samples plot away from this trend, indicating that crustal contamination contribution remained insignificant. This conclusion is also supported by the low 207Pb/204Pb ratios in the Guagua compared to Rucu lavas. Finally, in the Guagua lavas, the high 187Os/188Os ratios positively correlate with the adakitic character (high Sr/Y and La/Yb). [1] Samaniego S. et al. CMP 160 (2010) 239-260 [2] Schiano P. et al. CMP 160 (2010) 297-312 [3] Hidalgo S. et al. Lithos 132-133 (2012) 180-192 [4] Bourdon E. et al. J. Petrol. 43 (2002) 199-217 [5] Martin H. et al. Lithos 198-199 (2014) 1-13

Burns inflicted by self or by others--an 11 year snapshot.

PubMed

Malic, C C; Karoo, R O S; Austin, O; Phipps, A

2007-02-01

In the United Kingdom, the incidence of assault by burning and of self inflicted burns increased significantly over the last decade. This has major implications both for service providers and society as a whole. Our aim was to investigate the differences in patients' characteristics, management and outcome following a burn sustained by either an assault or self immolation. Acute admissions to a tertiary Burn Centre were retrospectively reviewed over an 11 year period (1994-2005). Demographic data and information regarding the circumstances surrounding the incident, burn severity, treatment and outcomes of the patients were collected. Over an 11 year period, 1745 patients were admitted to the tertiary Burn Centre. Of this total, 41 patients (mean age 29 years+/-16) sustained burns following an assault, a further 86 patients (mean age of 37 years+/-12) had self inflicted burn injuries; males were preponderant in both groups. In this series, a history of alcohol or substance abuse was present in 25% of both cohorts, 63% of the patients with self inflicted injuries having a previously diagnosed psychiatric disorder. Petrol, accelerants and other flammable liquids were the main agents chosen to inflict injury in both the assault and self inflicted groups. The burn depth and surface area distribution was greater in the self inflicted group compared to those assaulted (29% versus 21%). A difference was also noted in the pattern of distribution of burns between the two groups, as well as between genders although this difference was not significant. Two-thirds (67.4%) of the self immolated patients and 56% of the assaulted group required surgery. The length of hospital stay was similar for both groups, averaging 20 days. The crude mortality for the self inflicted group was 29%, whereas in the assaulted patients, the overall mortality was 4.9%. Although the incidence of burns caused either by assault or attempted suicide is low, the affected patients require a multidisciplinary approach. Their management requires significant medical, psychological occupational and social support. Increased awareness and education of those vulnerable individuals maybe of benefit to help prevent self inflicted injuries by burning.

Role of NSO compounds during primary cracking of a Type II kerogen and a Type III lignite

USGS Publications Warehouse

Behar, F.; Lorant, F.; Lewan, M.

2008-01-01

The aim of this work is to follow the generation of NSO compounds during the artificial maturation of an immature Type II kerogen and a Type III lignite in order to determine the different sources of the petroleum potential during primary cracking. Experiments were carried out in closed system pyrolysis in the temperature range from 225 to 350 ??C. Two types of NSOs were recovered: one is soluble in n-pentane and the second in dichloromethane. A kinetic scheme was optimised including both kerogen and NSO cracking. It was validated by complementary experiments carried out on isolated asphaltenes generated from the Type II kerogen and on the total n-pentane and DCM extracts generated from the Type III lignite. Results show that kerogen and lignite first decompose into DCM NSOs with minor generation of hydrocarbons. Then, the main source of petroleum potential originates from secondary cracking of both DCM and n-pentane NSOs through successive decomposition reactions. These results confirm the model proposed by Tissot [Tissot, B., 1969. Premie??res donne??es sur les me??canismes et la cine??tique de la formation du pe??trole dans les bassins se??dimentaires. Simulation d'un sche??ma re??actionnel sur ordinateur. Oil and Gas Science and Technology 24, 470-501] in which the main source of hydrocarbons is not the insoluble organic matter, but the NSO fraction. As secondary cracking of the NSOs largely overlaps that of the kerogen, it was demonstrated that bulk kinetics in open system is a result of both kerogen and NSO cracking. Thus, another kinetic scheme for primary cracking in open system was built as a combination of kerogen and NSO cracking. This new kinetic scheme accounts for both the rate and amounts of hydrocarbons generated in a closed pyrolysis system. Thus, the concept of successive steps for hydrocarbon generation is valid for the two types of pyrolysis system and, for the first time, a common kinetic scheme is available for extrapolating results to natural case studies. ?? 2007 Elsevier Ltd. All rights reserved.

Unradiogenic Pb Anomalies in Historical Lavas of Piton de la Fournaise (Reunion Island)

NASA Astrophysics Data System (ADS)

Vlastelic, I.

2008-12-01

A detailed investigation (218 samples) of Pb isotope variations in the most recent (1975-2007), well- documented and densely sampled eruptions of Piton de la Fournaise has been undertaken (Vlastelic et al, in press). Lead isotopes exhibit smooth temporal fluctuations (18.87<206Pb/204Pb<18.94) on which superimpose rare (5), but pronounced unradiogenic spikes (206Pb/204Pb down to 17.63). In 208Pb/204Pb vs. 206Pb/204Pb space, normal and anomalous samples plot along a single linear array. In 207Pb/204Pb vs. 206Pb/204Pb space, normal samples define an array whose slope (0.16) is commonly observed in ocean island basalts, whereas anomalous samples define less steep arrays (slopes down to 0.04). It follows that some of the anomalous samples have unusually high 207Pb/204Pb for their 206Pb/204Pb. These latter are enriched in Pb by a factor three. The lack of reproducibility of isotopic analyses suggests that samples are heterogeneous at a sub-millimeter scale. The origin of the unradiogenic anomalies is enigmatic. Leaching experiments rule out anthropogenic contamination. Interaction of plume melts with a contaminant genetically unrelated to the Reunion plume is possible although not supported by trace-element and Sr-Nd isotope signatures indistinguishable from normal lavas. On the other hand, interaction with or entrainment of Pb-rich, most likely unradiogenic sulfides could affect specifically Pb isotope compositions. Inspection of the well-know eruptions history reveals that the isotopic anomalies coincide with transitions from basalts to oceanites (lavas rich in cumulative olivine). Olivine and sulfides, which are both denser than silicate melts, could be entrained with magma pulses, which give rise to high-flux oceanite eruptions. Some sulfides may originate from the oceanic crust. Others may originate from sulfide solidus depth (c.a. 160 km) where sulfides melts are expected to pond (Hart and Gaetani, 2006). These deep sulfides melts could be remnants of past melting events of the Reunion plume. References Hart, S.R., Gaetani, G.A., 2006. Contrib. Mineral. Petrol. 152, 295-308. Vlastelic, I., et al., 2008. J. Volcanol. Geotherm. Res., in press.

Major to ultra trace elements in rainfall collected in suburban Tokyo

NASA Astrophysics Data System (ADS)

Shimamura, Tadashi; Iwashita, Masato; Iijima, Satoe; Shintani, Megumi; Takaku, Yuichi

Major to ultra trace elements such as rare earth elements (REEs), platinum group elements (PGEs) in 20 rainfall events from suburban Tokyo were determined by inductively coupled plasma mass spectrometry (ICP-MS). Anion species were also determined by an ion chromatography (IC). The concentrations of PGEs were so low that only Pt was detected in some rainfall events. Enrichment factors (EFs), refer to soil and sea salt components, were calculated for the measured elements (with Al and Na as references). Be, (Na), Mg, (Al), Si, Cl, K, Fe, Rb, Sr, REEs (except La, Gd), Ta, and U were mostly originated from natural materials (soil and sea salt). For Li, B, Ca, Mn, Sr, Ba, and Cs, the contribution of natural materials was significant. EFs for Cu, Zn, As, Se, Sb, Cd, Pb, Bi, Ag, Te, Au, Pt, SO 4-S and NO 3-N exceeded 100 indicating non-crustal, non-sea salt origin, presumably anthropogenic; however, contribution of volcanic gases could not be excluded for As, Se, Te and Bi. Pt seemed to be uniformly distributed worldwide and a catalyst for automobile emission control may be the main source. Au also showed uniform distribution. On the other hand, EFs for Zr, Nb, Hf and Th were less than unity. Probably these elements resided in acid resistant refractory fine minerals that did not decompose with acid treatment, and did not evaporate and ionize in the ICP. An alternative explanation is that the concentration of these elements was lower in the soil of the sampling area than the average crust. In the crust normalized REE pattern plot, La, Eu and Gd showed clear positive anomalies. La and Gd could have anthropogenic components. A possible source of La and Gd is cracking catalyst for petrol refining, but this source does not fully explain the anomaly. The source of Gd may also be Gd-DTPA (Gadolinium (III) diethyltriaminepentaacetic acid) used for Magnetic Resonance Imaging (MRI) contrast agents. The Eu origin may be soil with higher concentration than the crust average.

High Pressure Behavior of Zircon at Room Temperature

NASA Astrophysics Data System (ADS)

Reichmann, H. J.; Rocholl, A.

2016-12-01

Zircon, ZrSiO4, is an ubiquitous mineral in the Earth's crust, forming under a wide range of metamorphic and igneous conditions. Its high content in certain trace elements (REE, Hf, Th, U) and due to its isotopic information, together with its chemical and physical robustness makes zircon an unique geochemical tool and geochronometer. Despite its geological importance there is a disagreement regarding the responds of zircon to elevated pressure, especially about the commencement of a pressure - induced structural phase transition. At elevated pressure zircon (I41/amd) undergoes a pressure induced phase transition to the scheelite structure (I41/a) . In the low pressure and high pressure phase, the (SiO4)4- tetrahedral units are present. However, the onset of the phase transition at room temperature is not well defined: zircon - scheelite transitions have been reported in a pressure regime ranging from 20 to 30 GPa (e.g. Ono et al., 2004). To clarify this issue, we performed Raman spectroscopy measurement up to 60 GPa on a non-metamict single crystal zircon sample (reference material 91500; Wiedenbeck et al., 1995; Wiedenbeck et al., 2004). A closer look at the external lattice modes at 201 cm-1 shows a decreasing of the wavenumbers with increasing pressure up to 21 GPa followed by a steep increase. The lattice modes at 213 and 224 cm-1 also exhibit a subtle kink in this pressure range. This pressure coincides with that one reported for the zircon - scheelite transition (van Westrenen et al., 2004). Another interesting issue is the behavior of the internal modes at higher pressures. The ν3 stretching modes at about 1000 cm-1show distinct discontinuities at 31 GPa accompanied by the emerging of new features in the Raman spectrum suggesting another, pressure triggered modification in the zircon structure. References: Ono, Funakoshi, Nakajima, Tange, and Katsura (2004) Contr. Mineral. Petrol., 147, 505-509. Van Westrenen, Frank, Hanchar, Fei, Finch, and Zha (2004) American Mineralogist, 89, 197-203. Wiedenbeck et al., (1995) Geostandards Newsletter, 19, 1-23. Wiedenbeck et al. (2004) Geostandards and Geoanalytical Research, 28, 9-39.

Genotoxicity of air borne particulates assessed by comet and the Salmonella mutagenicity test in Jeddah, Saudi Arabia.

PubMed

Elassouli, Sufian M; Alqahtani, Mohamed H; Milaat, Waleed

2007-09-01

Fine airborne respirable particulates less than 10 micrometer (PM10) are considered one of the top environmental public health concerns, since they contain polycyclic aromatic hydrocarbons (PAHs) which are among the major carcinogenic compounds found in urban air. The objective of this study is to assess the genotoxicity of the ambient PM10 collected at 11 urban sites in Jeddah, Saudi Arabia. The PM10 extractable organic matter (EOM) was examined for its genotoxicity by the single cell gel electrophoresis (SCGE) comet assay and the Salmonella mutagenicity (Ames) test .Gas chromatography-mass spectrometry was used to quantify 16 PAH compounds in four sites. Samples from oil refinery and heavy diesel vehicles traffic sites showed significant DNA damage causing comet in 20-44% of the cells with tail moments ranging from 0.5-2.0 compared to samples from petrol driven cars and residential area, with comet in less than 2% of the cells and tail moments of < 0.02. In the Ames test, polluted sites showed indirect mutagenic response and caused 20-56 rev/ m3, mean while residential and reference sites caused 2-15 rev /m3. The genotoxicity of the EOM in both tests directly correlated with the amount of organic particulate and the PAHs concentrations in the air samples. The PAHs concentrations ranged between 0.83 ng/m3 in industrial and heavy diesel vehicles traffic sites to 0.18 ng /m3 in the residential area. Benzo(ghi)pyrene was the major PAH components and at one site it represented 65.4 % of the total PAHs. Samples of the oil refinery site were more genotoxic in the SCGE assay than samples from the heavy diesel vehicles traffic site, despite the fact that both sites contain almost similar amount of PAHs. The opposite was true for the mutagenicity in the Ames test. This could be due to the nature of the EOM in both sites. These findings confirm the genotoxic potency of the PM10 organic extracts to which urban populations are exposed.

High-Ca augites do not prove that komatiites were wet

NASA Astrophysics Data System (ADS)

Bouquain, S.; Arndt, N. T.; Faure, F.; Libourel, G.; Foley, S.

2006-12-01

Many spinifex-textured komatiitic basalts contain large zoned pyroxene needles containing an inner core of orthopyroxene, a central zone of magnesian pigeonite and an outer mantle of augite. New electron and ion microprobe analyses of pyroxene in spinifex needles from a 2.7 Ga komatiite flow from Alexo in Ontario show that the augite has a range of Wo contents, from 26 to 46 mol% and Mg# from 0.63 to 0.82. These compositions are similar to those reported by Shimizu et al. (2005, J Petrol) for augite from well-preserved komatiites from the Belingwe belt, Zimbabwe. The compositions of Alexo and Belingwe augites are broadly similar to those reported by Parman et al. (1997, EPSL) in augite from 3.5 Ga komatiites from the Barberton belt in South Africa (Wo = ~ 30 to 44 mol%); they differ only in that the Mg# of Barberton augites are higher (~0.82 to 0.88). Parman et al. (1997) used the high Wo contents to argue that the Barberton komatiites crystallized in shallow- level intrusions from relatively low temperature, hydrous, subduction-related komatiite magma. The intrusive komatiite hypothesis has been called in question by remapping of Barberton komatiites (Dann, 2000), and the high Wo contents of demonstrably anhydrous, extrusive komatiites from Alexo and Belingwe show that this feature does not require high water contents. We attribute the high Mg# of Barberton augites in part to the effects of alteration of the more metamorphosed Barberton komatiites and in part to the unusually high CaO/Al2O3 and SiO2 contents of these lavas, which causes augite to crystallize earlier than in the other komatiites. Ion probe analyses of trace elements in pigeonite and augite from Alexo komatiites are consistent with their crystallization from an incompatible-element depleted, plume-derived magma. The exclusion of the pyroxene hypothesis removes one of the last convincing arguments for wet, subduction-related komatiites. Although a few rare types of komatiite, such as those from Boston Creek in Ontario, contained modest water contents, the majority of komatiites come from a source that was essentially anhydrous and very hot.

Walking and cycling to work despite reporting an unsupportive environment: insights from a mixed-method exploration of counterintuitive findings.

PubMed

Guell, Cornelia; Panter, Jenna; Ogilvie, David

2013-05-24

Perceptions of the environment appear to be associated with walking and cycling. We investigated the reasons for walking and cycling to or from work despite reporting an unsupportive route environment in a sample of commuters. This mixed-method analysis used data collected as part of the Commuting and Health in Cambridge study. 1164 participants completed questionnaires which assessed the travel modes used and time spent on the commute and the perceived environmental conditions on the route to work. A subset of 50 also completed qualitative interviews in which they discussed their experiences of commuting. Participants were included in this analysis if they reported unsupportive conditions for walking or cycling on their route (e.g. heavy traffic) in questionnaires, walked or cycled all or part of the journey to work, and completed qualitative interviews. Using content analysis of these interviews, we investigated their reasons for walking or cycling. 340 participants reported walking or cycling on the journey to work despite unsupportive conditions, of whom 15 also completed qualitative interviews. From these, three potential explanations emerged. First, some commuters found strategies for coping with unsupportive conditions. Participants described knowledge of the locality and opportunities for alternative routes more conducive to active commuting, as well as their cycling experience and acquired confidence to cycle in heavy traffic. Second, some commuters had other reasons for being reliant on or preferring active commuting despite adverse environments, such as childcare arrangements, enjoyment, having more control over their journey time, employers' restrictions on car parking, or the cost of petrol or parking. Finally, some survey respondents appeared to have reported not their own environmental perceptions but those of others such as family members or 'the public', partly to make a political statement regarding the adversity of active commuting in their setting. Participants report walking and cycling to work despite adverse environmental conditions. Understanding this resilience might be just as important as investigating 'barriers' to cycling. These findings suggest that developing knowledge of safe walking and cycling routes, improving cycling confidence and restricting workplace parking may help to encourage walking and cycling to and from work.

Fluid Flow Patterns During Production from Gas Hydrates in the Laboratory compared to Field Settings: LARS vs. Mallik

NASA Astrophysics Data System (ADS)

Strauch, B.; Heeschen, K. U.; Priegnitz, M.; Abendroth, S.; Spangenberg, E.; Thaler, J.; Schicks, J. M.

2015-12-01

The GFZ's LArge Reservoir Simulator LARS allows for the simulation of the 2008 Mallik gas hydrate production test and the comparison of fluid flow patterns and their driving forces. Do we see the gas flow pattern described for Mallik [Uddin, M. et al., J. Can. Petrol Tech, 50, 70-89, 2011] in a pilot scale test? If so, what are the driving forces? LARS has a network of temperature sensors and an electric resistivity tomography (ERT) enabling a good spatial resolution of gas hydrate occurrences, water and gas distribution, and changes in temperature in the sample. A gas flow meter and a water trap record fluid flow patterns and a backpressure valve has controlled the depressurization equivalent to the three pressure stages (7.0 - 5.0 - 4.2 MPa) applied in the Mallik field test. The environmental temperature (284 K) and confining pressure (13 MPa) have been constant. The depressurization induced immediate endothermic gas hydrate dissociation until re-establishment of the stability conditions by a consequent temperature decrease. Slight gas hydrate dissociation continued at the top and upper lateral border due to the constant heat input from the environment. Here transport pathways were short and permeability higher due to lower gas hydrate saturation. At pressures of 7.0 and 5.0 MPa the LARS tests showed high water flow rates and short irregular spikes of gas production. The gas flow patterns at 4.2 MPa and 3.0MPa resembled those of the Mallik test. In LARS the initial gas surges overlap with times of hydrate instability while water content and lengths of pathways had increased. Water production was at a minimum. A rapidly formed continuous gas phase caused the initial gas surges and only after gas hydrate dissociation decreased to a minimum the single gas bubbles get trapped before slowly coalescing again. In LARS, where pathways were short and no additional water was added, a transport of microbubbles is unlikely to cause a gas surge as suggested for Mallik.

Walking and cycling to work despite reporting an unsupportive environment: insights from a mixed-method exploration of counterintuitive findings

PubMed Central

2013-01-01

Background Perceptions of the environment appear to be associated with walking and cycling. We investigated the reasons for walking and cycling to or from work despite reporting an unsupportive route environment in a sample of commuters. Methods This mixed-method analysis used data collected as part of the Commuting and Health in Cambridge study. 1164 participants completed questionnaires which assessed the travel modes used and time spent on the commute and the perceived environmental conditions on the route to work. A subset of 50 also completed qualitative interviews in which they discussed their experiences of commuting. Participants were included in this analysis if they reported unsupportive conditions for walking or cycling on their route (e.g. heavy traffic) in questionnaires, walked or cycled all or part of the journey to work, and completed qualitative interviews. Using content analysis of these interviews, we investigated their reasons for walking or cycling. Results 340 participants reported walking or cycling on the journey to work despite unsupportive conditions, of whom 15 also completed qualitative interviews. From these, three potential explanations emerged. First, some commuters found strategies for coping with unsupportive conditions. Participants described knowledge of the locality and opportunities for alternative routes more conducive to active commuting, as well as their cycling experience and acquired confidence to cycle in heavy traffic. Second, some commuters had other reasons for being reliant on or preferring active commuting despite adverse environments, such as childcare arrangements, enjoyment, having more control over their journey time, employers’ restrictions on car parking, or the cost of petrol or parking. Finally, some survey respondents appeared to have reported not their own environmental perceptions but those of others such as family members or ‘the public’, partly to make a political statement regarding the adversity of active commuting in their setting. Conclusions Participants report walking and cycling to work despite adverse environmental conditions. Understanding this resilience might be just as important as investigating ‘barriers’ to cycling. These findings suggest that developing knowledge of safe walking and cycling routes, improving cycling confidence and restricting workplace parking may help to encourage walking and cycling to and from work. PMID:23705951

Slab and Sediment Melting during Subduction Initiation: Mantle Plagiogranites from the Oman Ophiolite

NASA Astrophysics Data System (ADS)

Rollinson, H. R.

2014-12-01

Granitoid dykes up to several hundred metres wide and 2 km long are found in depleted harzburgites in the mantle section of the Oman ophiolite. They vary in composition from tonalite to potassic granite and are generally more potassic than the crustal plagiogranites found within the sheeted dyke complex higher up within the ophiolite stratigraphy. Some granites are strongly peraluminous and contain garnet and andalusite. They are geochemically variable, some with REE that are relatively unfractionated ((La/Yb)n= 3.5-6.0, flat middle to heavy REE, steep light REE) to those which are highly fractionated ((La/Yb)n= 28-220). On primitive-mantle normalised plots some have very high concentrations of fluid-mobile elements - Cs, Rb, Th, U and Pb. Few have significant Ta-Nb anomalies. On the Ca-Fe-Mg-Ti discrimination diagram of Patino Douce (J. Petrol., 1999) whole-rock compositions define a spectrum between felsic-pelite derived melts and amphibolite-derived melts. There is a chemical similarity between the least REE fractionated plagiogranites (generally tonalites and granodiorites) and melts of an amphibolitic parent. This is supported by the occurrence of mafic xenoliths in some dykes, the presence of hornblende and highly calcic cores (up to An85) in some plagioclase grains. Trace element modelling using Oman Geotimes lavas as the starting composition indicates that melting took place in the garnet stability field, although enrichment in the melt in Cs, Rb, Ba and Pb suggests that there was another component present in addition to the mafic parent. Other plagiogranites (trondhjemites and granites) have a strongly peraluminous chemistry and mineralogy and geochemical similarities with the Himalayan leucogranites implying that they were derived from a sedimentary protolith. These mantle plagiogranites are more prevalent in the northern outcrops of the ophiolite. The volume of granitoid melt and the depth of melting preclude their derivation from the sole of the ophiolite, rather they were derived during subduction by the partial melting of the slab and associated sediment and emplaced into the overlying mantle wedge. Current subduction-initiation models for supra-subduction ophiolites should integrate this process into their thinking.

The impact of permafrost-associated microorganisms on hydrate formation kinetics

NASA Astrophysics Data System (ADS)

Luzi-Helbing, Manja; Liebner, Susanne; Spangenberg, Erik; Wagner, Dirk; Schicks, Judith M.

2016-04-01

The relationship between gas hydrates, microorganisms and the surrounding sediment is extremely complex: On the one hand, microorganisms producing methane provide the prerequisite for gas hydrate formation. As it is known most of the gas incorporated into natural gas hydrates originates from biogenic sources. On the other hand, as a result of microbial activity gas hydrates are surrounded by a great variety of organic compounds which are not incorporated into the hydrate structure but may influence the formation or degradation process. For gas hydrate samples from marine environments such as the Gulf of Mexico a direct association between microbes and gas hydrates was shown by Lanoil et al. 2001. It is further assumed that microorganisms living within the gas hydrate stability zone produce biosurfactants which were found to enhance the hydrate formation process significantly and act as nucleation centres (Roger et al. 2007). Another source of organic compounds is sediment organic matter (SOM) originating from plant material or animal remains which may also enhance hydrate growth. So far, the studies regarding this relationship were focused on a marine environment. The scope of this work is to extend the investigations to microbes originating from permafrost areas. To understand the influence of microbial activity in a permafrost environment on the methane hydrate formation process and the stability conditions of the resulting hydrate phase we will perform laboratory studies. Thereby, we mimic gas hydrate formation in the presence and absence of methanogenic archaea (e.g. Methanosarcina soligelidi) and other psychrophilic bacteria isolated from permafrost environments of the Arctic and Antarctic to investigate their impact on hydrate induction time and formation rates. Our results may contribute to understand and predict the occurrences and behaviour of potential gas hydrates within or adjacent to the permafrost. Lanoil BD, Sassen R, La Duc MT, Sweet ST, Nealson KH (2001). Bacteria and Archaea Physically Associated with Gulf of Mexico Gas Hydrates. Appl Environ Microbiol 67: 5143-5153. Rogers R, Zhang G, Dearman J, Woods C (2007). Investigations into surfactant/gas hydrate relationship. J Petrol Sci Eng 56: 82-88.

Basanite-nephelinite suite from early Kilauea: carbonated melts of phlogopite-garnet peridotite at Hawaii's leading magmatic edge

NASA Astrophysics Data System (ADS)

Sisson, T. W.; Kimura, J.-I.; Coombs, M. L.

2009-12-01

A basanite-nephelinite glass suite from early submarine Kilauea defines a continuous compositional array marked by increasing concentrations of incompatible components with decreasing SiO2, MgO, and Al2O3. Like peripheral and post-shield strongly alkalic Hawaiian localities (Clague et al. in J Volcanol Geotherm Res 151:279-307, 2006; Dixon et al. in J Pet 38:911-939, 1997), the early Kilauea basanite-nephelinite glasses are interpreted as olivine fractionation products from primary magnesian alkalic liquids. For early Kilauea, these were saturated with a garnet-phlogopite-sulfide peridotite assemblage, with elevated dissolved CO2 contents responsible for the liquids’ distinctly low-SiO2 concentrations. Reconstructed primitive liquids for early Kilauea and other Hawaiian strongly alkalic localities are similar to experimental 3 GPa low-degree melts of moderately carbonated garnet lherzolite, and estimated parent magma temperatures of 1,350-1,400°C (olivine-liquid geothermometry) match the ambient upper mantle geotherm shortly beneath the base of the lithosphere. The ~3 GPa source regions were too hot for stable crystalline carbonate and may have consisted of ambient upper mantle peridotite containing interstitial carbonate-silicate or carbonatitic liquid, possibly (Dixon et al. in Geochem Geophys Geosyst 9(9):Q09005, 2008), although not necessarily, from the Hawaiian mantle plume. Carbonate-enriched domains were particularly susceptible to further melting upon modest decompression during upward lithospheric flexure beneath the advancing Hawaiian Arch, or by conductive heating or upward drag by the Hawaiian mantle plume. The early Kilauea basanite-nephelinite suite has a HIMU-influenced isotopic character unlike other Hawaiian magmas (Shimizu et al. in EOS Tran Amer Geophys Union 82(47): abstr V12B-0962, 2001; Shimizu et al. in Geochim Cosmochim Acta 66(15A):710, 2002) but consistent with oceanic carbonatite involvement (Hoernle et al. in Contrib Mineral Petrol 142:520-542, 2002). It may represent the melting products of a fertile domain in the ambient upper mantle impinged upon and perturbed by the sustained plume source that feeds later shield-stage magmatism.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peche, Roberto, E-mail: roberto.peche@ehu.es; Rodriguez, Esther, E-mail: esther.rodriguez@ehu.e

This study shows the practical application of the EIA method based on fuzzy logic proposed by the authors (Peche and Rodriguez, 2009) to a simplified case of study-the activity of a petrol station throughout its exploitation. The intensity (p{sub 1}), the extent (p{sub 2}) and the persistence (p{sub 3}) were the properties selected to describe the impacts and their respective assessment functions v-bar{sub i}=f(p-bar{sub i}) were determined. The main actions (A) and potentially affected environmental factors (F) were selected. Every impact was identified by a pair A-F and the values of the three impact properties were estimated for each ofmore » them by means of triangular fuzzy numbers. Subsequently, the fuzzy estimation of every impact was carried out, the estimation of the impact A{sub 1}-F{sub 2} (V-bar{sub 1}) being explained in detail. Every impact was simultaneously represented by its corresponding generalised confidence interval and membership function. Since the membership functions of all impacts were similar to triangular fuzzy numbers, a triangular approach (TA) was used to describe every impact. A triangular approach coefficient (TAC) was introduced to quantify the similarity of each fuzzy number and its corresponding triangular approach, where TAC (V-bar) element of (0, 1] and TAC being 1 when the fuzzy number is triangular. The TACs-ranging from 0.96 to 0.99-proved that TAs were valid in all cases. Next, the total positive and negative impacts-TV-bar{sup +} and TV-bar{sup -} were calculated and later, the fuzzy value of the total environmental impact TV-bar was determined from them. Finally, the defuzzification of TV-bar led to the punctual impact estimator TV{sup (1)} = -88.50 and its corresponding uncertainty interval [{delta}{sub l}(TV-bar),{delta}{sub r}(TV-bar)]=[6.52,6.96], which represent the total value of the EI. In conclusion, the EIA method enabled the integration of heterogeneous impacts, which exerted influence on environmental factors of a very diverse nature in very different ways, into a global impact indicator.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lepicier, Veronique; Chiron, Mireille; Joumard, Robert, E-mail: robert.joumard@laposte.net

The goal of this study is to develop an emission based indicator for the health impact of the air pollution caused by traffic. This indicator must make it possible to compare different situations, for example different Urban Travel Plans, or technical innovations. Our work is based on a literature survey of methods for evaluating health impacts and, more particularly, those which relate to the atmospheric pollution caused by transport. We then define a health impact indicator based on the traffic emissions, named IISCEP for Chronic health impact indicator of pollutant emission. Here health is understood in a restricted meaning, excludingmore » well-being. Only primary pollutants can be considered, as the inputs are emission data and an indicator must be simple. The indicator is calculated as the sum of each pollutant emission multiplied by a dispersion and exposition factor and a substance specific toxicity factor taking account of the severity. Last, two examples are shown using the IISCEP: comparison between petrol and diesel vehicles, and Nantes urban district in 2008 vs 2002. Even if it could still be improved, IISCEP is a straightforward indicator which can be used to gauge the chronic effects of inhaling primary pollutants. It can only be used in comparisons, between different scenarios or different technologies. The quality of the emissions data and the choice of the pollutants that are considered are the two essential factors that determine its validity and reliability. - Highlights: Black-Right-Pointing-Pointer The goal of the study is to develop an emission based indicator for the health impact of the air pollution caused by traffic. Black-Right-Pointing-Pointer It is based on a literature survey of methods for evaluating health impacts related to the atmospheric pollution. Black-Right-Pointing-Pointer We define a composite indicator based on the traffic emissions and on local data as dispersion conditions and population. Black-Right-Pointing-Pointer The indicator is a combination of pollutant emission, dispersion, exposition factor, and substance specific toxicity factor. Black-Right-Pointing-Pointer Applications are global (e.g. comparison of vehicle technologies) or local (e.g. comparison of populations or areas).« less

Microinclusions in polycrystalline diamonds: insights into processes of diamond formation

NASA Astrophysics Data System (ADS)

Jacob, D. E.; Wirth, R.; Enzmann, F.; Schwarz, J. O.; Kronz, A.

2009-04-01

Polycrystalline diamond aggregates (framesites) contain silicates of eclogitic and peridotitic affinity (e.g. Kurat and Dobosi, 2000). The minerals occur mostly in interstices and are intimately intergrown with the diamonds, indicating contemporaneous crystallization within the diamond stability field in the Earth's mantle. In addition to silicates, rarer phases such as Fe-carbide can sometimes be found in framesites that record unusually low local oxygen fugacity at the time of their formation (Jacob et al., 2004). Furthermore, while most gem-sized diamonds have old, often Archaean formation ages, some polycrystalline diamond aggregates have been shown to form directly preceding the kimberlite eruption (Jacob et al., 2000). Thus, these samples may provide a unique source of information on the nature and timing of small scale processes that lead to diamond formation and complement evidence from gem-sized diamonds. Here, we present a study of micro- and nano-inclusions in diamonds from a polycrystalline diamond aggregate (framesite) from the Orapa Mine (Botswana) and combine results from TEM/FIB analyses with high-resolution computerized micro-tomography (HR-µCT) and electron microprobe analyses to further constrain the formation of diamond in the Earth's mantle. Results In total, 14 microinclusions from fifteen FIB foils were investigated. Micro- and nano-inclusions identified by TEM were smaller than 1µm down to ca. 50nm in size, and are both monomineralic and multi-phase. The cavities are often lath-shaped and oriented parallel to each other; many show lattice dislocations in the surrounding diamond. In addition, inclusions are found along open cracks within the diamond single crystals. Mineral phases in the microinclusions comprise rutile, omphacite and a FeS phase (pyrrhotite). The multiphase inclusions most often consist of cavities that are only partly occupied (less than 50% of the total space), suggesting that the empty space was originally filled by a fluid. One multiphase inclusion was found to be still fluid-bearing, showing characteristic continuous changes in diffraction contrast due to density fluctuations caused by the electron beam. No other elements than carbon were detected during AEM of this area which suggests that the fluid consists of relatively pure C-H-O species. In addition to the fluid, this inclusion contained fine-grained FeS, a silicate phase rich in Fe, P, Mg, Al, Ca and K and a quench phase, rich in Fe, P and Si. Macroinclusions (>5µm) are magnetite, often surrounded by hematite, FeS, low-Cr garnet (Py50Alm39Grs11) and omphacite (Jd23). Garnet and cpx were found as non-touching inclusions and yield 1256°C at 5 GPa. Most of the magnetite inclusions are single crystals and some are strongly deformed with signs of recrystallization. Hematite occurs as porous aggregates of nano-granules of ca. 5-7 nm sizes. High Resolution µ-Computer Tomography (HR-µCT) shows pores in the sample and the included mineral phases as areas of differing grey-values. These are a direct function of the specific x-ray density of the specific phase and can be used to differentiate oxides and silicates. Based on the 3D tomogram, the amount of pores per total volume of the diamond plus inclusion matrix is calculated to be 0.65 vol%, while magnetite inclusions amount to 3.16 vol%. The average equivalent radius of the magnetite grains (radius of a sphere with the same volume as the grain) is 17.8 µm, while that of the pores is 12.6µm. Discussion The occurrence of omphacite, rutile and FeS as microinclusions within the diamond crystals clearly shows that these phases are cogenetic to the diamonds. However, magnetite and hematite were only encountered as large inclusions in cavities that appear to be interstitial porosity. Moreover, analysis of the equivalent radius distribution of the pores and the magnetite inclusions derived from HR-µCT shows a complete overlap of the mode, indicating that magnetite preferentially fills the porosity in the sample. Furthermore, hematite occurs exclusively along the outer rim of the magnetite crystals and textural features suggest that this phase is a late replacement product of magnetite. This shows that the magnetite-bearing cavities were not shielded from the outside by the host diamond and may indicate that magnetite itself was introduced after diamond formation or during a secondary event that may still, however, have taken place at PT conditions of the diamond stability field. The microinclusion suite described here is distinct from that found in fibrous (e.g. Klein-BenDavid et al., 2007) and in microdiamonds (Kvasnytsya et al., 2006). Carbonates, halides and phosphates, that are typical for fibrous and microdiamonds were not encountered in our study. Instead, the microinclusion suite found in the framesite consists of the typical eclogitic minerals (rutile, garnet, omphacite, sulphide) plus a C-H-O fluid. Jacob et al., 2004. Contrib. Mineral. Petrol., 146, 566-576. Jacob et al., 2000. Science, 289, 1182-1185. Klein-BenDavid et al., 2007. Amer. Mineral. 91, 353-365. Kurat and Dobosi, 2000. Mineral. Petrol. 69, 143-159. Kvasnytsya et al., 2006. Ukrainian Geologist 2, 25-36.

An EMPA investigation of the redox state of natural glasses from mantle xenoliths and mantle-derived boninitic magmas.

NASA Astrophysics Data System (ADS)

Fialin, Michel; Wagner, Christiane; Ohnenstetter, Daniel

2010-05-01

An EMPA investigation of the redox state of natural glasses from mantle xenoliths and mantle-derived boninitic magmas. M. Fialin1*, C. Wagner2, and D. Ohnenstetter3 1 Centre de Microanalyse Camparis, UPMC Univ Paris 06, CNRS-UMR 7094, IPGP, F-75005, Paris, France. * michel.fialin@upmc.fr 2 Lab. "Magmas, Minéraux, Matériaux", UPMC Univ. Paris 06, CNRS-UMR 7193, iSTeP, F-75005, Paris, France. 3 CRPG, CNRS-UPR 2300, BP20, 54501 Vandœuvre-lès-Nancy, France The recent developments of the electron microprobe analytical procedures in our laboratory allow the direct measurement of the glass ferric-ferrous ratios at a scale of a few micrometer. The determination of the oxidation state of iron is based on the measure of the self-absorption induced shift of the emitted Fe L peak [1, 2, 3]. This method is well suited for the study of glassy phases of few tens of squared micrometers disseminated in a mineral matrix. It can be operated on common petrographic thin sections and, thus, it can be easily coupled with conventional chemical analyses by electron probe microanalysis (EPMA). This latter point is essential because the total Fe content of the glass must be precisely measured by EPMA to scale the corresponding Fe-L peak position relative to the calibration curves giving the Fe3+/SFe ratios. The samples studied are spinel lherzolite from the French Massif Central, and low Ca type 1 boninites from dykes cutting serpentinized peridotite at Népoui, New Caledonia. Glass occurs commonly in mantle xenoliths as small (<10 micrometers) patches in reactional rims but its origin remains controversy and has been interpreted in relation to mantle processes or to interactions with the xenolith host magma. We have previously demonstrated that these xenoliths have been metasomatized, and that the glasses are reaction products between mantle phases and migrating melts [3, 4]. The consensus emerging from different studies is that metasomatism is oxidizing relative to both primitive shallow (spinel-bearing) and deep (garnet-bearing) lithosphere [5, 6, 7]. It is thus of great interest to measure directly the glass ferric-ferrous ratios at a scale of a few µm. In the lherzolite, the glassy pockets formed around primary spinel contain small (10-30 micrometers) secondary phases and abundant bubble-like voids, suggesting a former high content of volatiles removed during degassing. The glasses have a phono-tephrite to trachy-andesite, a composition in the range of that reported for world-wide peridotite xenoliths [6], with low FeO (~3 wt.%) and H2O (< 1wt.%) contents. The boninites contain abundant (48 vol. %) fresh glass of dacitic composition with low FeO (2 wt. %) and rich in H2O (~5-6 wt. %). In both samples, the glass is in contact with Cr-spinel which shows (in mantle xenolith) or not (in boninite) a sieve-textured rim resulting from a coupled dissolution-precipitation process. The secondary spinels of the rim are enriched in Cr and depleted in Al. With or without a sieve-textured rim, the spinel shows a hematite rim at the contact with the glass. The high (0.6-0.8 ±0.04 at 1sigma) EMP Fe3+/SFe ratio measured in the glass from the lherzolite samples strongly contrasts with the calculated melt fO2 (FMQ ± 1) from the composition of secondary phases. Thus, the measured ratio does not reflect the original redox state of the migrating melt but is consistent with the late-stage reworking of the sample under oxidized conditions (hematite deposition). Measuring the Fe3+/SFe ratios in highly hydrated glasses, such as those in boninite (up to 6 wt% H2O) is challenging, due to beam damage caused during the analysis. Nevertheless values in the range Fe3+/SFe=0.7-0.8 were measured for the glass, in good agreement with the Fe3+/SFe ratios for the iron oxides formed as late epitaxial layers grown onto the early cristallized spinels. [1] Fialin et al. (2001) Am. Mineral. 86, 456-472. [2] Fialin et al. (2004) Am. Mineral., 89,654-662. [3] Wagner et al. (2008) Am. Mineral., 93, 1273-1281. [3] Wagner and Deloule (2007) Geochim. Cosmochim. Acta, 71, 4279-4296. [4] Wagner and Fialin (2008) Goldschmidt Conf. 2008, Geochim. Cosmochim. Acta. 72, A990. [5] Balhaus et al. (1991) Contrib. Mineral. Petrol., 107, 27-40. [6] Amundsen and Neumann (1992) Redox control during mantle/melt interaction. Geochim. Cosmochim. Acta, 56, 2405-2416. [7] Creighton et al. (2009) Contrib. Mineral. Petrol., 157, 491-504. [6] Coltorti et al., 2000, EPSL, 183, 303-320..

Investigation of potential of agro-industrial residues for ethanol production by using Candida tropicalis and Zymomonas mobilis

NASA Astrophysics Data System (ADS)

Patle, Sonali

India is becoming more susceptible regarding energy security with increasing world prices of crude oil and increasing dependence on imports. Based on experiments by the Indian Institute of Petroleum, a 10% ethanol blend with gasoline is being considered for use in vehicles in at least one state and it will be mandatory for all oil companies to blend petrol with 10% ethanol from October 2008. In view of the above, the Government has already started supply of 5% ethanol blended petrol from 2003 in nine states and four contiguous Union Territories. Currently, fuel ethanol is produced mainly from molasses, corn, wheat and sugar beets. The production cost of ethanol from these agro-feedstocks is more than twice the price of gasoline. The high feedstock cost poses a major obstacle to large scale implementation of ethanol as a transportation fuel. Molasses could be in short supply due to the implementation of 10% blending norm. A reduction in import duty for industrial alcohol from7.5% to 5% has been suggested. The use of lignocellulosic energy crops, and particularly low cost biomass residues, offers excellent perspectives for application of ethanol in transportation fuels (Ridder, 2000). These materials will increase the ethanol production capacity and reduce the production cost to a competitive level. There is a huge demand (500 million litres) of ethanol to meet the 5% blending in India. With the present infrastructure, only 90 million litres of ethanol was produced till November 2006 and could reach up to 140 million litres (around) till October 2007. Bioethanol from these materials provides a highly cost effective option for CO2 emission reduction in the transportation sector. The aim of the present investigation was to evaluate the potential of biomass as feedstock for ethanol production. The dedicated energy crops would require thorough support as well as planning efforts such as assessing resources, availability and utilization. Furthermore, applied research is needed to develop environmentally and socially acceptable low-cost, high quality crops and cropping systems for producing sufficient quantities of value added biomass feedstock on substantially larger areas. This would require taking a look at environmental implications and economic assessments as over 70% of Indian population directly or indirectly depends on agricultural income sources. In other words, a long term strategy of intensive research would be required to get the desired level of acceptance both by the researchers and the farmers. This would mean long term field trials with the newly developed energy crops, awareness creation, and demonstration of visual benefits to farmers leading to change in mind-set towards greater flexibility for cropping patterns. This holds enormous promising research and development opportunities, but substantially longer period might be required to achieve these goals. The petroleum industry is now committed to the use of ethanol as fuel, as it is expected to benefit sugarcane farmers as well as the oil industry in the long run. Production of ethanol from agricultural and biodegradable wastes provides a viable solution to multiple environmental problems simultaneously creating a sink for waste and renewable energy production as well. Using ethanol-blended fuels for automobiles can significantly reduce petroleum use. Ethanol is one of the best tools to fight vehicular pollution, contains more oxygen that helps complete combustion of fuel and thus reduces harmful tailpipe emissions. It also reduces particulate emissions that pose a health hazard. Currently, fuel grade ethanol is produced from sugarcane, corn, wheat and sugar beets but the ethanol production cost from these substrates is very high as compared to gasoline. This high feedstock cost is the biggest hindrance in large scale implementation of ethanol as a transportation fuel. To counter the high feedstock costs, use of lignocellulosic materials, such as crop residues, grasses, sawdust, wood chips etc., can be promoted, which presents an inexpensive and abundant renewable source for ethanol production. Also there is an enormous production of fruits and vegetables in India and a very huge amount goes waste due to post-harvest losses and a large quantity of unused portion is also generated from processing industries. These substrates can be used as a potential source for ethanol production. These substrates are complex and are required to be broken down into simple sugars by acid, alkaline or enzymatic treatment. Two common methods for converting complex substrates to fermentable sugars are dilute acid hydrolysis and concentrated acid hydrolysis, both of which use either HCl or H2 So4. Since, acid hydrolysis has few disadvantages enzymatic hydrolysis was explored and found to be a better and more economic option. After substrate selection and its hydrolysis, it is very important to optimize the fermentation parameters and scale up the process. Different agro-industrial substrates were explored for this process. (Abstract shortened by UMI.)

REE Mineralization in Kiruna-type Magnetite-Apatite Ore Deposits: Magmatism and Metasomatism

NASA Astrophysics Data System (ADS)

Harlov, D. E.

2015-12-01

Magnetite-apatite ore bodies of the Kiruna type occur worldwide and are generally associated with volcanic rocks or volcanism. They also show strong evidence of extensive metasomatism over a wide P-T range. Notable examples include the Kiirunavaara ore body, northern Sweden (Harlov et al., 2002, Chem. Geol., 191, 47-72); the Grängesberg ore body, central Sweden (Jonsson et al., 2010, NGF abstracts, vol 1, 88-89); the Mineville ore body, Adirondacks, New York, USA (McKeown and Klemc, 1956, U.S. Geol Sur Bull (1956), pp. 9-23); the Pea Ridge ore body, SE Missouri, USA (Kerr, 1998, MS Thesis, Univ. Windsor, Windsor, Ontario, Canada 113 pp); the Jurassic Marcona ore body in south-central Peru (Chen et al., 2010, Econ Geol, 105, 1441-1456); and a collection of ore bodies from the Bafq Region, central Iran (Daliran et al., 2010, Geol. Assoc. Canada, Short Course Notes, v. 20, p.147-159). In these ore bodies, low Th and U monazite, xenotime, allanite, REE carbonates, and/or REE fluorides are commonly associated with the apatite as inclusions, rim grains, or as independent grains in the surrounding mineral matrix. High contrast BSE imaging, coupled with EMPA and LA-ICPMS, indicates that the apatite has experienced fluid-induced alteration in the form of (Y+REE) + Na + Si + Cl depletion implying that it served as the source for the (Y+REE) (e.g. Kiirunavaara, northern Sweden; Harlov et al., 2002). Formation of monazite and xenotime associated with fluorapatite, as inclusions or rim grains, has experimentally been demonstrated to originate from the fluorapatite as the result of fluid-aided, coupled dissolution-reprecipitation processes (Harlov et al., 2005, Contrib. Mineral. Petrol. 150, 268-286). This is explains the low Th and U content of the monazite and xenotime. Fluid sources could range from 700-900 °C, residual, acidic (HCl, H2HSO4) grain boundary fluids, remaining after the last stages of ore body crystallization, to later stage, cooler (< 600 °C) (H2O-CO2-(Na,K)Cl) fluids originating in the surrounding country rock or as fluids associated with metamorphic events such as regional albitization or actinolization. The abundance of (Y+REE)-bearing minerals in these deposits suggests that in addition to being mined for their Fe ore, they could also be economically mined for (Y+REE) as well.

A protocol for a systematic review of the effectiveness of interventions to reduce exposure to lead through consumer products and drinking water

PubMed Central

2014-01-01

Background The toxic heavy metal lead continues to be a leading environmental risk factor, with the number of attributable deaths having doubled between 1990 and 2010. Although major sources of lead exposure, in particular lead in petrol, have been significantly reduced in recent decades, lead is still used in a wide range of processes and objects, with developing countries disproportionally affected. The objective of this systematic review is to assess the effectiveness of regulatory, environmental and educational interventions for reducing blood lead levels and associated health outcomes in children, pregnant women and the general population. Methods/design The databases MEDLINE, Embase and the Global Health Library (GHL) will be searched using a sensitive search strategy. Studies in English, German, French, Spanish, Italian or Afrikaans will be screened according to predefined inclusion and exclusion criteria. We will consider randomized and non-randomized studies accepted by the Cochrane Effective Practice and Organization of Care (EPOC) Group, as well as additional non-randomized studies. Screening of titles and abstracts will be performed by one author. Full texts of potentially relevant studies will be independently assessed for eligibility by two authors. A single author will extract data, with a second reviewer checking the extraction form. Risk of bias will be assessed by two researchers using the Graphical Appraisal Tool for Epidemiological studies, as modified by the Centre for Public Health at the UK National Institute for Health and Care Excellence. Any inconsistencies in the assessment of eligibility, data extraction or quality appraisal will be resolved through discussion. Where two or more studies report the primary outcome blood lead levels within the same population group, intervention category and source of lead exposure, data will be pooled using random effects meta-analysis. In parallel, harvest plots as a graphical method of evidence synthesis will be used to present findings for blood lead levels and secondary outcomes. Discussion This systematic review will fill an important evidence gap with respect to the effectiveness of interventions to reduce lead in consumer products and drinking water in the context of new WHO guidelines for the prevention and management of lead poisoning. It will also contribute to setting a future research agenda. PMID:24731516

Release of Nitrogen during Planetary Accretion Explains Missing Nitrogen in Earth's Mantle

NASA Astrophysics Data System (ADS)

Liu, J.; Dorfman, S.; Lv, M.; Li, J.; Kono, Y.

2017-12-01

Nitrogen and carbon are essential elements for life on Earth, and their relative abundances in planetary bodies (C/N ratios) are important for understanding planetary evolution and habitability1,2. However, the high C/N ratio in the bulk silicate Earth relative to CI chondrites and other volatile-rich chondrites is difficult to explain with partitioning behavior between silicate and metallic liquid or solubility in silicate melt, and has thus been a major unsolved problem in geochemistry1-5. Because core formation does not explain nitrogen depletion in the mantle, another process is required to match the observed BSE C/N ratio, such as devolatilization of metallic liquid. Previous studies have examined the Fe-C phase diagram extensively (e.g. ref. 6), but very limited melting data is available for the Fe-N system7. Here we examine melting relations for four Fe-N-C compositions with 1-7 wt% nitrogen up to 7 GPa and 2200 K in the Paris-Edinburgh press by a combination of in-situ X-ray radiography, X-ray diffraction and ex-situ electron microprobe techniques. In striking contrast to the Fe-C system, near-surface melting in all compositions in the Fe-N-C system entails release of nitrogen fluid and depletion of nitrogen from the liquid alloy. This could provide a pathway for nitrogen to escape the magma ocean in the accretion stage while carbon is retained. On the basis of our experimental results, we propose a new quantitative model of mantle nitrogen evolution during the core formation stage to explain the high BSE C/N ratios and resolve the paradox of missing mantle nitrogen1-5. Although nitrogen itself is not a greenhouse gas, the nitrogen released to the atmosphere from metallic melt early in Earth's history could amplify the greenhouse effect through collision-enhanced absorption8,9, which may help to explain warm surface temperatures during the Hadean and Archean eras on Earth when the solar luminosity was 25-30% lower than the present10. References1. Bergin et al., PNAS (2015). 2. Hirschmann, Am. Mineral. (2016). 3. Marty, EPSL (2012). 4. Halliday, GCA (2013). 5. Dalou et al., EPSL (2017). 6. Walker et al., Contrib. Mineral. Petrol. (2013). 7. Guillermet et al., Z. Metallkd. (1994). 8. Wordsworth et al., Science (2013). 9. Goldblatt et al. Nat. Geosci. (2009). 10. Gough. Sol. Phys. (1981)

The influence of magma degassing on entrapment pressures recorded in olivine-hosted melt inclusions

NASA Astrophysics Data System (ADS)

Gaetani, G. A.

2013-12-01

The concentrations of H2O and CO2 in olivine-hosted melt inclusions provide estimates for the pressures at which they were entrapped, and represent an important source of information on the depths at which basaltic magmas crystallize [1]. Results from recent dehydration experiments demonstrate that diffusive loss of H2O from melt inclusions, driven by degassing of the external magma, leads to significant decreases to pressure within the inclusion [2, 3]. This, in turn, lowers the solubility of CO2 in the included melt causing a vapor to exsolve and form a bubble. This process has the potential to significantly modify estimates of entrapment pressures derived from volatile concentrations in olivine hosted melt inclusions. I have developed a quantitative model that describes this process, allowing the influence of degassing on entrapment pressures to be rigorously evaluated. Diffusive loss of H2O from the inclusions was determined using the model of [3]. An equation of state (EOS) for the silicate melt was taken from the results of [4] and [5], while the EOS for H2O-CO2 vapor was taken from [6]. The solubilities of H2O and CO2 in the silicate melt were derived from VolatileCalc [7]. Modeling results demonstrate that degassing of H2O-rich magma produces significant pressure drops, so that entrapment pressures never exceed crustal values and always represent a minimum. Conversely, degassing of H2O-poor magma does not significantly perturb the H2O content of olivine-hosted melt inclusions. Therefore, these inclusions preserve reliable records of the pressures at which they were entrapped. These results are consistent with a global compilation of olivine-hosted melt inclusion entrapment pressures presented by [3]. References: [1] Wanless, VD, and Shaw, AM, Nature Geosci, 5, 651-655 (2012); [2] Gaetani, GA, et al., Geology, 40, 915-918 (2012); [3] Bucholz, CE, et al., Earth Planet Sci Lett, 374, 145-155 (2013); [4] Lange, R. A., and Carmichael, ISE, Geochim Cosmochim Acta, 51, 2931-2946, (1987); [5] Kress, VC, and Carmichael, ISE, Contrib Mineral Petrol, 108, 82-92 (1991); [6] Duan, Z, and Zhang, Z, Geochim Cosmochim Acta, 70, 2311-2324 (2006); [7] Newman, S, and Lowenstern, JB, Comput Geosci, 28, 597-604 (2002).

The distribution of lead concentrations and isotope compositions in the eastern Tropical Atlantic Ocean

NASA Astrophysics Data System (ADS)

Bridgestock, Luke; Rehkämper, Mark; van de Flierdt, Tina; Paul, Maxence; Milne, Angela; Lohan, Maeve C.; Achterberg, Eric P.

2018-03-01

Anthropogenic emissions have dominated marine Pb sources during the past century. Here we present Pb concentrations and isotope compositions for ocean depth profiles collected in the eastern Tropical Atlantic Ocean (GEOTRACES section GA06), to trace the transfer of anthropogenic Pb into the ocean interior. Variations in Pb concentration and isotope composition were associated with changes in hydrography. Water masses ventilated in the southern hemisphere generally featured lower 206Pb/207Pb and 208Pb/207Pb ratios than those ventilated in the northern hemisphere, in accordance with Pb isotope data of historic anthropogenic Pb emissions. The distributions of Pb concentrations and isotope compositions in northern sourced waters were consistent with differences in their ventilation timescales. For example, a Pb concentration maximum at intermediate depth (600-900 m, 35 pmol kg-1) in waters sourced from the Irminger/Labrador Seas, is associated with Pb isotope compositions (206Pb/207Pb = 1.1818-1.1824, 208Pb/207Pb = 2.4472-2.4483) indicative of northern hemispheric emissions during the 1950s and 1960s close to peak leaded petrol usage, and a transit time of ∼50-60 years. In contrast, North Atlantic Deep Water (2000-4000 m water depth) featured lower Pb concentrations and isotope compositions (206Pb/207Pb = 1.1762-1.184, 208Pb/207Pb = 2.4482-2.4545) indicative of northern hemispheric emissions during the 1910s and 1930s and a transit time of ∼80-100 years. This supports the notion that transient anthropogenic Pb inputs are predominantly transferred into the ocean interior by water mass transport. However, the interpretation of Pb concentration and isotope composition distributions in terms of ventilation timescales and pathways is complicated by (1) the chemical reactivity of Pb in the ocean, and (2) mixing of waters ventilated during different time periods. The complex effects of water mass mixing on Pb distributions is particularly apparent in seawater in the Tropical Atlantic Ocean which is ventilated from the southern hemisphere. In particular, South Atlantic Central Water and Antarctic Intermediate Water were dominated by anthropogenic Pb emitted during the last 50-100 years, despite estimates of much older average ventilation ages in this region.

Ge and Fe Isotope Fractionation in Metabasites during Subduction-Zone Metamorphism

NASA Astrophysics Data System (ADS)

Luais, B.; El Korh, A. M. T.; Boiron, M. C.; Deloule, E.; Cividini, D.

2016-12-01

Non-traditional stable isotope fractionation during subduction of oceanic crust provides a powerful but challenging tool for understanding geochemical processes in the sub-arc mantle. Iron and germanium are strongly sensitive to low-temperature (T) hydrothermal processes (< 350°C), but can also fractionate at high-T (>700°C) [1-4]. We measured Fe and Ge isotopes in high-pressure metabasites of hydrothermally altered MORB (1.7-2.3 GPa; 550-600°C [5]) from the Ile de Groix (France) to study their behaviour during subduction and fluid-rock interactions. Eclogites and blueschists have δ74GeNIST3120a values (+0.42-0.65‰) similar to those of tholeiitic basalts (+0.55-0.57‰ [2]), indicating a negligible effect of hydrothermal alteration on δ74Ge values. Weak decreases in δ74Ge values occur during dehydration from blueschist to eclogite facies, and in greenschists showing evidence of restricted fluid-rock interaction, but remain close to the HP range (+0.39-0.49‰). This near constancy is attributed to stability of garnet, the main Ge host. By contrast, albite and calcite-bearing greenschists that suffer garnet breakdown show evidence of Ge isotope fractionation (δ74Ge = +0.84-0.98‰) during intensive fluid interaction in a reduced context (Fe2+/Fetot= 0.77-0.80). The metabasites have δ56FeIRMM-014 values (+0.16-0.33‰) heavier than MORBs-OIBs (+0.07-0.18‰ [3]). Unlike Ge isotopes, Fe isotopes correlate with HFSE and mainly reflect protolith heterogeneity. The increase in δ56Fe compared to igneous basic rocks results from open-system hydrothermal alteration prior to subduction. Small correlated variations in Fe elemental (Fe2+/Fetot) and isotopic compositions between blueschists, eclogites and greenschists suggest that Fe isotope fractionation was buffered by the iron of the basic protoliths during subduction and exhumation. Thus metasomatism related to fluids derived from subducted hydrothermally altered metabasites might have little effect on mantle Ge and Fe isotope compositions under subsolidus conditions. [1] Rouxel et al 2003, Chem Geol 202, 155-182. [2] Luais 2012. Chem Geol 334, 295-311. [3] Teng et al, 2013, GCA 107, 12-26. [4] Escoube et al 2015. GCA 167, 93-112. [5] El Korh et al 2009, J Petrol 50, 1107-1148.

Tobacco promotion 'below-the-line': exposure among adolescents and young adults in NSW, Australia.

PubMed

Perez, Donna A; Grunseit, Anne C; Rissel, Chris; Kite, James; Cotter, Trish; Dunlop, Sally; Bauman, Adrian

2012-06-12

Exposure to tobacco advertising and promotion increases the likelihood of smoking amongst young people. While there is a universal ban on traditional or ‘above-the-line’ advertising in Australia, the types and extent of exposure of young people to ‘below-the-line’ tobacco advertising and promotion is largely unknown. In this study we aim to identify levels of exposure of New South Wales (NSW) adolescents and young adults to tobacco promotion at the point-of-sale (PoS), on the internet, in entertainment media and at venues such as events or festivals and pubs, clubs, nightclubs, or bars; and to identify those most at risk of exposure. A telephone survey of 1000 NSW adolescents and young adults aged 12 to 24 years was conducted. Self-reported exposure to tobacco promotions or advertising in the last month were measured in four areas: (1) promotions or advertising at (a) events or festivals and (b) pubs, clubs, nightclubs or bars, (2) on the internet, (3) people smoking cigarettes in (a) movies, (b) TV shows, (c) video games and (d) on the internet, and (4) displays of cigarette packs for sale at (a) large supermarkets, (b) grocery stores or small supermarkets, (c) convenience stores, and (d) service or petrol stations. Smoking status and susceptibility to smoking was also assessed. A substantial proportion of the young people surveyed reported seeing tobacco promotion sometimes or often in the last month over most of the channels studied.The highest levels of exposure were at the PoS (approx. two-thirds) and to people smoking cigarettes in movies(77%). Lower levels of exposure to tobacco promotions and imagery were reported on the internet (20%); at events or festivals (22.5%); in pubs, clubs, nightclubs or bars (31%); and in video games (23%). However, the odds of exposure through video games increased by 8% for every additional hour spent on the internet per day. This study shows that adolescents and young adults in NSW are exposed to tobacco advertising or promotion at the PoS, on the internet, in entertainment media and at venues such as events or festivals and pubs, clubs, nightclubs or bars, despite the restrictions on the marketing of tobacco in Australia.

Trace element diffusion in minerals: the role of multiple diffusion mechanisms operating simultaneously

NASA Astrophysics Data System (ADS)

Dohmen, R.; Marschall, H.; Wiedenbeck, M.; Polednia, J.; Chakraborty, S.

2016-12-01

Diffusion of trace elements, often with ionic charge that differs from those of ions in the regular structural sites of a mineral, controls a number of important processes in rocks, such as: (i) Closure of radiogenic isotopic systems, (e.g. Pb diffusion in rutile; REE diffusion in garnet); (ii) Closure of trace element thermometers (e.g., Zr in rutile, Mg in plagioclase, Al in olivine); (iii) Closure of element exchange between melt inclusions and host minerals (e.g., H, REE in olivine). In addition, preserved trace element zoning profiles in minerals can be used for diffusion chronometry (e.g. Nb in rutile, Mg in plagioclase). However, experimentally determined diffusion coefficients of these trace elements are in many cases controversial (e.g., REE in olivine: [1] vs. [2]; Mg in plagioclase: [3] vs. [4]). We have carried out experiments to study the diffusion behavior in olivine, rutile, and plagioclase, and are able to show that two mechanisms of diffusion, differing in rates by up to four orders of magnitude, may operate simultaneously in a given crystal. The two mechanisms result in complex diffusion profile shapes. As a general rule, the incorporation of heterovalent substituting elements in relatively high concentrations is necessary to activate two diffusion mechanisms. This behavior is produced by the control of these elements on the point defect chemistry of a mineral - these impurities become a majority point defect when a threshold concentration limit is exceeded. In certain cases, e.g., for Li in olivine, the trace element can also be incorporated in different sites, resulting in interaction of the different species with other point defects (vacancies) during diffusion. Thus, depending on the diffusion couple used in the experiment, the associated concentration gradients within the mineral, and the analytical techniques used to measure the diffusion profile, only one diffusion mechanism may be activated or detected. These studies allow us to explain some of the differing results noted above and such considerations need to be taken into account when modelling diffusion in natural systems. [1] Cherniak 2010, Am Mineral 95:362-368; [2] Spandler and O'Neill 2010, Contrib Mineral Petrol 159:791-818; [3] Faak et al. 2013 Geochim Cosmochim Acta 123:195-217; [4] Van Orman et al. 2014 Earth Planet Sci Lett 385:79-88

A novel approach to in-situ rutile petrochronology

NASA Astrophysics Data System (ADS)

Kooijman, Ellen; Smit, Matthijs; Kylander-Clark, Andrew

2017-04-01

Rutile petrochronology has become an increasingly important tool for deciphering the timing and conditions of petrological processes. Rutile provides a reliable single-mineral thermometer, capable of retaining temperature information during high and ultra-high temperature metamorphism. Its HFSE contents can be used to investigate the geochemical environment in which rutile crystallized. Most importantly, rutile strongly fractionates U/Pb and enables U-Pb thermochronology in the intermediate temperature range. Here we present a novel approach to using U-Pb thermochronology of rutile by exploring the use of Pb as a diffusive species in kinetics-based thermometry. We performed high spatial and analytical resolution micro-analysis of rutile by laser ablation multi-collector ICPMS to constrain Pb diffusion profiles in rutile from high-grade metamorphic rocks of the Western Gneiss Complex (WGC), Norway. The age and thermometric results from this analysis are used to constrain a full thermal history from single grains. Millimeter-sized single crystals of rutile from a rutile-rich phlogopitite vein in eclogite were mounted and polished to expose their geometric cores. The grains were analyzed in transects using rectangular spots (c. 15x45 μm). This ensures ablation of a significant volume while maintaining the required radial spatial resolution. The transects yielded well-defined Pb diffusion profiles, with U-Pb ages ranging from c. 415 Ma in the cores to c. 380 Ma in the outermost rims (±2%, 2σ on individual spots). Diffusion zoning length was used with well-established Pb diffusion parameters [1] to determine peak temperature conditions following the approach of [2]. The result, c. 810 ± 25 ˚ C, is consistent with 800 ± 25 ˚ C and c. 780 ˚ C estimated for the same sample using conventional and Zr-in-rutile thermometry, respectively. The cooling history that is reconstructed through age zoning analysis and diffusion modeling shows remarkable consistency with that established for the WGC through decades of 40Ar/39Ar dating. The data presented here demonstrate that in-situ rutile U-Pb analysis yields reliable and precise temperature and age information that can be combined to resolve full thermal histories from single crystals. This novel approach to the toolbox of rutile petrochronology has great potential for research into the tectonics and dynamics of the lithosphere. References [1] Cherniak (2000) Contrib. Mineral. Petrol. 139. 198-207. [2] Smit et al. (2013) J. Metamorph. Geol. 31. 339-358.

Thermoelasticity and high- T behaviour of anthophyllite

NASA Astrophysics Data System (ADS)

Welch, Mark D.; Cámara, Fernando; Oberti, Roberta

2011-04-01

The thermoelastic behaviour of anthophyllite has been determined for a natural crystal with crystal-chemical formula ANa0.01 B(Mg1.30Mn0.57Ca0.09Na0.04) C(Mg4.95Fe0.02Al0.03) T(Si8.00)O22 W(OH)2 using single-crystal X-ray diffraction to 973 K. The best model for fitting the thermal expansion data is that of Berman (J Petrol 29:445-522, 1988) in which the coefficient of volume thermal expansion varies linearly with T as α V,T = a 1 + 2 a 2 ( T - T 0): α298 = a 1 = 3.40(6) × 10-5 K-1, a 2 = 5.1(1.0) × 10-9 K-2. The corresponding axial thermal expansion coefficients for this linear model are: α a ,298 = 1.21(2) × 10-5 K-1, a 2, a = 5.2(4) × 10-9 K-2; α b ,298 = 9.2(1) × 10-6 K-1, a 2, b = 7(2) × 10-10 K-2. α c ,298 = 1.26(3) × 10-5 K-1, a 2, c = 1.3(6) × 10-9 K-2. The thermoelastic behaviour of anthophyllite differs from that of most monoclinic ( C2/ m) amphiboles: (a) the ɛ 1 - ɛ 2 plane of the unit-strain ellipsoid, which is normal to b in anthophyllite but usually at a high angle to c in monoclinic amphiboles; (b) the strain components are ɛ 1 ≫ ɛ 2 > ɛ 3 in anthophyllite, but ɛ 1 ~ ɛ 2 ≫ ɛ 3 in monoclinic amphiboles. The strain behaviour of anthophyllite is similar to that of synthetic C2/ m ANa B(LiMg) CMg5 TSi8 O22 W(OH)2, suggesting that high contents of small cations at the B-site may be primarily responsible for the much higher thermal expansion ⊥(100). Refined values for site-scattering at M4 decrease from 31.64 epfu at 298 K to 30.81 epfu at 973 K, which couples with similar increases of those of M1 and M2 sites. These changes in site scattering are interpreted in terms of Mn ↔ Mg exchange involving M1,2 ↔ M4, which was first detected at 673 K.

Northernmost Known Outcrop in North America of Lower Cretaceous Porphyritic Ocoite Facies (Ocoa, Chile) at Western Mexico: the Talpa Ocoite

NASA Astrophysics Data System (ADS)

Zárate-del Valle, P. F.; Demant, A.

2003-04-01

At Talpa de Allende region in Western Mexico is located the northernmost known outcrop of ocoite facies (andesite): the Talpa ocoite (TO). The ocoite facies consists of an calk-alkaline andesitic rock rich in K and characterized by the presence of megacrysts of plagioclase (An48-65). TO belongs to the so-called Guerrero Terrane composed of plutono-volcanic and volcano-sedimentary sequences of the Alisitos-Teloloapan arc that was accreted to the North American craton at the end of the early Cretaceous (Lapierre et al., 1992, Can. J. Earth Sci. 29. 2478--2489). Geodynamically TO belongs to lithological sequence number IV or "Tecoman" of Tardy et al. (1994, Tectonophysics 230, 49--73). TO in hand-sample shows typical megacrysts (>1 cm) of plagioclase and clinopyroxene in a dark green aphanitic matrix. This andesitic lava has a shoshonitic character as evidenced by chemical composition: SiO_2 TiO_2 Al_2O_3 Fe_2O_3 MnO MgO CaO Na_2O K_2O P_2O_5 LOI % Ba Sr (ppm) 55.64 0.73 16.61 8.39 0.13 3.59 6.40 3.55 2.85 0.36 1.84% 1093 880 Under microscope TO is characterized by a porphyritic texture made of large labradorite phenocrysts (up to 3 cm) and clinopyroxene with a matrix made of plagioclase microlites; TO has been affected by a low grade metamorphism process belonging to the prehnite-pumpellite facies as it happens in Chile (Levi, 1969, Contr. Mineral. and Petrol. 24-1, p. 30--49). Electron microprobe analysis shows that plagioclase (An55-57) is partly transformed into albite (An7-9); clinopyroxene shows a variation in composition from Wo33En41Fs17 to Wo40En44Fs24 and it is transformed towards the margin first into amphibole and then into biotite. TO outcrops located at East of Talpa river are affected by a deep rubefaction process. TO is not characterized by the presence of bitumen as it occurs in Northern Chile (Nova-Muñoz et al., 2001, EUG XI Meeting, OS09 Supo09 PO, 606); TO is related in time with albian-cenomanian volcanogenic massive sulphides of Western Mexico: La América and El Rubí mines.

3D-Modeling of deformed halite hopper crystals: Object based image analysis and support vector machine, a first evaluation

NASA Astrophysics Data System (ADS)

Leitner, Christoph; Hofmann, Peter; Marschallinger, Robert

2014-05-01

Halite hopper crystals are thought to develop by displacive growth in unconsolidated mud (Gornitz & Schreiber, 1984). The Alpine Haselgebirge, but also e.g. the salt deposits of the Rhine graben (mined at the beginning of the 20th century), comprise hopper crystals with shapes of cuboids, parallelepipeds and rhombohedrons (Görgey, 1912). Obviously, they deformed under oriented stress, which had been tried to reconstruct with respect to the sedimentary layering (Leitner et al., 2013). In the present work, deformed halite hopper crystals embedded in mudrock were automated reconstructed. Object based image analysis (OBIA) has been used successfully in remote sensing for 2D images before. The present study represents the first time that the method was used for reconstruction of three dimensional geological objects. First, manually a reference (gold standard) was created by redrawing contours of the halite crystals on each HRXCT scanning slice. Then, for OBIA, the computer program eCognition was used. For the automated reconstruction a rule set was developed. Thereby, the strength of OBIA was to recognize all objects similar to halite hopper crystals and in particular to eliminate cracks. In a second step, all the objects unsuitable for a structural deformation analysis were dismissed using a support vector machine (SVM) (clusters, polyhalite-coated crystals and spherical halites) The SVM simultaneously drastically reduced the number of halites. From 184 OBIA-objects 67 well shaped remained, which comes close to the number of pre-selected 52 objects. To assess the accuracy of the automated reconstruction, the result before and after SVM was compared to the reference, i.e. the gold standard. State-of the art per-scene statistics were extended to a per-object statistics. Görgey R (1912) Zur Kenntnis der Kalisalzlager von Wittelsheim im Ober-Elsaß. Tschermaks Mineral Petrogr Mitt 31:339-468 Gornitz VM, Schreiber BC (1981) Displacive halite hoppers from the dead sea: Some implications for ancient evaporite deposits. J of Sediment Petrol 51:787-794. doi: 10.1306/212F7DAB-2B24-11D7-8648000102C1865D Leitner C, Neubauer F, Marschallinger R, Genser J, Bernroider M (2013) Origin of deformed halite hopper crystals, pseudomorphic anhydrite cubes and polyhalite in Alpine evaporates (Austria, Germany). Int J Earth Sc 102, pp 813-829, doi: 10.1007/s00531-012-0836-6

Magma batches in the Timber Mountain magmatic system, Southwestern Nevada Volcanic Field, Nevada, USA

NASA Astrophysics Data System (ADS)

Mills, James G.; Saltoun, Benjamin W.; Vogel, Thomas A.

1997-09-01

The common occurrence of compositionally and mineralogically zoned ash flow sheets, such as those of the Timber Mountain Group, provides evidence that the source magma bodies were chemically and thermally zoned. The Rainier Mesa and Ammonia Tanks tuffs of the Timber Mountain Group are both large volume (1200 and 900 km 3, respectively) chemically zoned (57-78 wt.% SiO 2) ash flow sheets. Evidence of distinct magma batches in the Timber Mountain system are based on: (1) major- and trace-element variations of whole pumice fragments; (2) major-element variations in phenocrysts; (3) major-element variations in glass matrix; and (4) emplacement temperatures calculated from Fe-Ti oxides and feldspars. There are three distinct groups of pumice fragments in the Rainier Mesa Tuff: a low-silica group and two high-silica groups (a low-Th and a high-Th group). These groups cannot be related by crystal fractionation. The low-silica portion of the Rainier Mesa Tuff is distinct from the low-silica portion of the overlying Ammonia Tanks Tuff, even though the age difference is less than 200,000 years. Three distinct groups occur in the Ammonia Tanks Tuff: a low-silica, intermediate-silica and a high-silica group. Part of the high-silica group may be due to mixing of the two high-silica Rainier Mesa groups. The intermediate-silica group may be due to mixing of the low- and high-silica Ammonia Tanks groups. Three distinct emplacement temperatures occur in the Rainier Mesa Tuff (869, 804, 723 °C) that correspond to the low-silica, high-Th and low-Th magma batches, respectively. These temperature differences could not have been maintained for any length of time in the magma chamber (cf. Turner, J.S., Campbell, I.H., 1986. Convection and mixing in magma chambers. Earth-Sci. Rev. 23, 255-352; Martin, D., Griffiths, R.W., Campbell, I.H., 1987. Compositional and thermal convection in magma chambers. Contrib. Mineral. Petrol. 96, 465-475) and therefore eruption must have occurred soon after emplacement of the magma batches into the chamber. Emplacement temperatures of the pumice fragments from the Ammonia Tanks Tuff show a continuous gradient of temperatures with composition. This continuous temperature gradient is consistent with the model of storage of magma batches in the Ammonia Tanks group that have undergone both thermal and chemical diffusion.

Lipid Biomarker Records Across the Permian-Triassic Boundary from Kap Stosch, Greenland

NASA Astrophysics Data System (ADS)

Hays, L. E.; Love, G. D.; Foster, C. B.; Grice, K.; Summons, R. E.

2006-12-01

The end-Permian extinction was the most severe in the past 500 million years of the Earth's history and evidence that an oceanic anoxic event (OAE) occurred contemporaneously has been presented previously [1,2]. OAEs have, therefore, been proposed as responsible for the mass mortality, and if the anoxic ocean was also euxinic, the release of hydrogen sulfide during upwelling and/or transgression provides an extinction agent in the ocean as well as on land. Chlorobiaceae, as indicators of photic zone euxinia (PZE), utilize hydrogen sulfide as an electron donor for anoxygenic photosynthesis. The detection of isorenieratane and a series of short-chain monoaromatic aryl isoprenoids, biomarkers for Chlorobiaceae, in sediments indicates the presence of hydrogen sulfide in the photic zone of the water column during sediment deposition. The Kap Stosch area in Eastern Greenland was identified as a Permian-Triassic boundary (PTB) outcrop of homogeneous shale, silty shale, and siltstone facies [3]. Another late Permian section in Eastern Greenland, the Ravnefjeld Formation, has framboidal pyrites indicative of sulfidic deep water [4]. A sample suite from the Kap Stosch region was studied using standard organic geochemistry methods including stable isotopic analyses of organic carbon, Rock-Eval pyrolysis, and biomarker hydrocarbon analysis. Aryl isoprenoids, including isorenieratane, were present in all samples studied and the concentrations were observed to fluctuate in tandem with TOC, similar to other Mesozoic OAEs. The molecular ratios of pristane/phytane and hopanes/steranes as well as the 2-methyl-hopane index (2-MHI) fluctuated dramatically through this section as they do at the type section at Meishan and in the Perth Basin [5]. The 2-MHI shows an inverse pattern to the total aryl isoprenoids, perhaps indicative of instability in the form of primary productivity in the water column during euxinic episodes. This can result in nitrogen limitation and a competitive advantage of cyanobacteria over microalgae for nutrient resources [6]. Overall, the biomarker patterns in these samples indicate the presence of PZE at this location leading up to and continuing through the PTB. 1. Isozaki Y., 1997. Science 276, 235. 2. Wignall P. and R. Twichett, 1996. Science 272, 1155. 3. Teichert C. and B. Kummel, 1972. Bull. Canadian Petrol. Geol. 20, 659. 4. Nielsen J. and Y. Shen, 2004. Geology 32, 1037. 5. Grice K., et al., 2005. Science 307, 706. 6. Kuypers M., et al., 2004. Geology 32, 853.

Tectonomagmatic significance of the picrite-rhyolite volcanism in the Northern Ethiopian plateau area

NASA Astrophysics Data System (ADS)

Natali, Claudio; Beccaluva, Luigi; Bianchini, Gianluca; Siena, Franca

2010-05-01

The Oligocene Continental Flood Basalts (CFB) of the Northern Ethiopia and the conjugate Yemen province testifies a huge volcanic event related to the "Afar plume" occurred at ca. 30 Ma (in 1 Ma or less; Hofmann et al., 1997) prior to the continental rifting stage. The zonal arrangement of CFB lavas with Low-Ti tholeiites (LT) in the west, High-Ti tholeiites (HT1) to the east and very High-Ti transitional basalts and picrites (HT2, TiO2 4-6 wt%) closer to the Afar triple junction has been considered a record of magmas generated from the flanks to the centre of a plume head, currently corresponding to the Afar hotspot (Beccaluva et al., 2009). In the central-eastern part of the plateau (Lalibela area), neighbouring the Afar escarpment, abundant rhyolites characterize the upper part of the volcanic sequence and have been interpreted as the differentiated products of CFB magmas (Ayalew et al., 2006). The unusual association of picrite and rhyolite magmas erupted in an elongated area, parallel to the Afar escarpment, appears to be related to peculiar tectonomagmatic events developed in the apical zone of a stretched lithosphere impinged by a mantle plume. As previously suggested, the HT basaltic and picritic magmas could have been generated in the innermost part (core) of the plume head from the hottest, deepest and most metasomatised mantle domains, enriched by "plume components" (Beccaluva et al., 2009). The late stages of these magmatic events were accompanied by the onset of continental rifting, with faulting and block tilting, leading to favourable conditions for magma differentiation in shallow (crustal) chambers located N-S along the future Afar Escarpment. Quantitative petrological modelling shows that efficient fractional crystallization processes of HT transitional basaltic magmas could result in highly differentiated peralkaline rhyolitic products, generally localized at the top (lower density) of the magma reservoirs. From these latter, abundant rhyolitic magma were erupted (sometimes alternating to HT basalts and picrites) during the paroxystic extensional phases which ultimately led to continental break-up and the formation of the Red Sea-Gulf of Aden-East African rift system centred in the Afar "triple junction". References: Ayalew et al. (2006). Geol. Soc. London Sp. Pub. 259, 121-130. Beccaluva et al. (2009). J. Petrol. 50, 1377-1403. Hofmann et al. (1997). Nature 389, 838-841.

Permeability Changes in Reaction Induced Fracturing

NASA Astrophysics Data System (ADS)

Ulven, Ole Ivar; Malthe-Sørenssen, Anders; Kalia, Rajiv

2013-04-01

The process of fracture formation due to a volume increasing chemical reaction has been studied in a variety of different settings, e.g. weathering of dolerites by Røyne et al.[4], serpentinization and carbonation of peridotite by Rudge et al.[3] and replacement reactions in silica-poor igneous rocks by Jamtveit et al.[1]. It is generally assumed that fracture formation will increase the net permeability of the rock, and thus increase the reactant transport rate and subsequently the total reaction rate, as summarised by Kelemen et al.[2]. Røyne et al.[4] have shown that transport in fractures will have an effect on the fracture pattern formed. Understanding the feedback process between fracture formation and permeability changes is essential in assessing industrial scale CO2 sequestration in ultramafic rock, but little is seemingly known about how large the permeability change will be in reaction-induced fracturing under compression, and it remains an open question how sensitive a fracture pattern is to permeability changes. In this work, we study the permeability of fractures formed under compression, and we use a 2D discrete element model to study the fracture patterns and total reaction rates achieved with different permeabilities. We achieve an improved understanding of the feedback processes in reaction-driven fracturing, thus improving our ability to decide whether industrial scale CO2 sequestration in ultramafic rock is a viable option for long-term handling of CO2. References [1] Jamtveit, B, Putnis, C. V., and Malthe-Sørenssen, A., "Reaction induced fracturing during replacement processes," Contrib. Mineral Petrol. 157, 2009, pp. 127 - 133. [2] Kelemen, P., Matter, J., Streit, E. E., Rudge, J. F., Curry, W. B., and Blusztajn, J., "Rates and Mechanisms of Mineral Carbonation in Peridotite: Natural Processes and Recipes for Enhanced, in situ CO2 Capture and Storage," Annu. Rev. Earth Planet. Sci. 2011. 39:545-76. [3] Rudge, J. F., Kelemen, P. B., and Spiegelman, M., "A simple model of reaction induced cracking applied to serpentinization and carbonation of peridotite," Earth Planet. Sci. Lett. 291, Issues 1-4, 2010, pp. 215 - 227. [4] Røyne, A., Jamtveit, B., and Malthe-Sørenssen, A., "Controls on rock weathering rates by reaction-induced hierarchial fracturing," Earth Planet. Sci. Lett. 275, 2008, pp. 364 - 369.

Recent evidence concerning higher NO x emissions from passenger cars and light duty vehicles

NASA Astrophysics Data System (ADS)

Carslaw, David C.; Beevers, Sean D.; Tate, James E.; Westmoreland, Emily J.; Williams, Martin L.

2011-12-01

Ambient trends in nitrogen oxides (NO x) and nitrogen dioxide (NO 2) for many air pollution monitoring sites in European cities have stabilised in recent years. The lack of a decrease in the concentration of NO x and in particular NO 2 is of concern given European air quality standards are set in law. The lack of decrease in the concentration of NO x and NO 2 is also in clear disagreement with emission inventory estimates and projections. This work undertakes a comprehensive analysis of recent vehicle emissions remote sensing data from seven urban locations across the UK. The large sample size of 84,269 vehicles was carefully cross-referenced to a detailed and comprehensive database of vehicle information. We find that there are significant discrepancies between current UK/European estimates of NO x emissions and those derived from the remote sensing data for several important classes of vehicle. In the case of light duty diesel vehicles it is found that NO x emissions have changed little over 20 years or so over a period when the proportion of directly emitted NO 2 has increased substantially. For diesel cars it is found that absolute emissions of NO x are higher across all legislative classes than suggested by UK and other European emission inventories. Moreover, the analysis shows that more recent technology diesel cars (Euro 3-5) have clear increasing NO x emissions as a function of Vehicle Specific Power, which is absent for older technology vehicles. Under higher engine loads, these newer model diesel cars have a NO x/CO 2 ratio twice that of older model cars, which may be related to the increased use of turbo-charging. Current emissions of NO x from early technology catalyst-equipped petrol cars (Euro 1/2) were also found to be higher than emission inventory estimates - and comparable with NO x emissions from diesel cars. For heavy duty vehicles, it is found that NO x emissions were relatively stable until the introduction of Euro IV technology when emissions decreased by about 30%. The more limited data available for urban buses shows that there has been little change in NO x emissions from Euro I to Euro IV. There is general much better consistency across the different estimates of heavy duty vehicle NO x emissions than for light duty vehicles.

Experimental Investigation of Orthoenstatite Single Crystal Rheology

NASA Astrophysics Data System (ADS)

fraysse, G.; Girard, J.; Holyoke, C. W.; Raterron, P.

2013-12-01

The plasticity of enstatite, upper mantle second most abundant mineral, is still poorly constrained, mostly because of its high-temperature (T) transformation into proto- and clino-enstatite at low pressure (P). Mackwell (1991, GRL, 18, 2027) reports a pioneer study of protoenstatite (Pbcn) single-crystal rheology, but the results do not directly apply to the orthorhombic (Pbca) mantle phase. Ohuchi et al. (2011, Contri. Mineral. Petrol , 161, 961) carried out deformation experiments at P=1.3 GPa on oriented orthoenstatite crystals, investigating the activity of [001](100) and [001](010) dislocation slip systems; they report the first rheological laws for orthoenstatite crystals. However, strain and stress were indirectly constrained in their experiments, which questioned whether steady state conditions of deformation were achieved. Also, data reported for [001](100) slip system were obtained after specimens had transformed by twinning into clinoenstatite. We report here new data from deformation experiments carried out at high T and P ranging from 3.5 to 6.2 GPa on natural Fe-bearing enstatite single crystals, using the Deformation-DIA apparatus (D-DIA) that equipped the X17B2 beamline of the NSLS (NY, USA). The applied stress and specimen strain rates were measured in situ by X-ray diffraction and imaging techniques (e.g., Raterron & Merkel, 2009, J. Sync. Rad., 16, 748; Raterron et al., 2013, Rev. Sci. Instr., 84, 043906). Three specimen orientations were tested: i) with the compression direction along [101]c crystallographic direction, which forms a 45° angle with both [100] and [001] axes, to investigate [001](100) slip-system activity; ii) along [011]c direction to investigate [001](010) system activity; iii) and along enstatite [125] axis, to activate both slip systems together. Crystals were deformed two by two, to compare slip system activities, or against enstatite aggregates or orientated olivine crystals of known rheology for comparison. Run products microstructures were investigated by transmission electron microscopy. Despite a significant hardening with P, enstatite [001](100) slip system is found to be the easiest system at mantle P and T. Furthermore, orthoenstatite crystals exhibit a higher sensitivity to stress than olivine crystals, i.e. a higher n exponent in classical power laws. At the low stress level prevailing in the Earth mantle, enstatite crystals are thus harder than olivine crystals.

Geochronology of high-pressure granulites from the Czech part of the Zlote Unit (Bohemian Massif)

NASA Astrophysics Data System (ADS)

Lange, U.; Bröcker, M.; Trapp, E.

2003-04-01

At the NE margin of the Bohemian Massif, granulites occur in the Zlote Unit which is exposed in the border region between Poland and the Czech Republic [e.g. 1, 3]. On the Polish side, outcrop conditions are rather poor. Besides some isolated blocks, granulites are restricted to a very small occurrence near Stary Gieraltow. This exposure has attracted much attention due to findings of presumed coesite pseudomorphs, as inferred from radial fractures around polycrystalline quartz inclusions in garnet [1]. Peak metamorphic conditions were estimated between 21 and 28 kbar at 800 to 1000 °C [2]. Better outcrop conditions of the same tectonic unit are found on the Czech side in the Rychleby Mts [3]. The focus of this study is on the geochronology of granulites from this occurrence. By means of Sm-Nd (garnet, cpx, whole rock) and single grain U-Pb dating of zircon, we have studied felsic and mafic granulites collected near the location Cerveny Dul. A felsic granulite yielded a Sm-Nd age of 337 +/- 4 Ma (two grain-size fractions of garnet, whole rock). Two mafic granulites provided Sm-Nd ages (two grain-size fractions of garnet, cpx and/or whole rock) of 357 +/- 10 Ma and 351 +/- 10 Ma, respectively. The new Sm-Nd results are in good agreement with metamorphic ages reported for other Bohemian granulites and further document the significance of HP-HT metamorphism at c. 350-340 Ma. Single-grain zircon dating of air-abraded grains provided concordant results. Zircons from a mafic granulite yielded an age of 362 +/- 1 Ma. A similar result was reported for a mafic granulite from Stary Gieraltow, based on conventional multigrain analyses of zircon [2]. This age is considered to approximate the timing of crystallisation from a melt. However, it remains unclear whether this process took place before or during early stages of high-pressure metamorphism. The studied felsic granulite yielded a range in zircon ages between 390 to 330 Ma, indicating the presence of inherited magmatic grains and the influence of anatectic processes post-dating the pressure peak. [1] Bakun-Czubarow (1992): Arch. Mineral. 48, 3-25; [2] Klemd, R. &Bröcker, M. (1999): Contrib. Mineral. Petrol. 136, 358-373; [3] Pouba, Z., Padera, K. &Fiala, J. (1985): N. Jahrb. Mineral., Abh. 151, 29-52

Fe-based redox state of mantle eclogites: Inherited from oceanic protoliths, modified during subduction or overprinted during metasomatism?

NASA Astrophysics Data System (ADS)

Aulbach, S.; Woodland, A. B.; Vasilyev, P.; Viljoen, F.

2016-12-01

Kimberlite-borne mantle eclogite xenoliths of Archaean and Palaeoproterozoic age are commonly interpreted as representing former oceanic crust. As such, they may retain a memory of the redox state of the convecting mantle source that gave rise to their magmatic protoliths and which controls the speciation of volatiles in planetary interiors. Mantle eclogite suites commonly include both cumulate and variably evolved extrusive varieties [1], which may be characterised by initial differences in Fe3+/Fetotal. However, in the warmer ancient mantle, they were also subject to modification due to partial melt loss upon subduction (if a plate tectonic regime existed) and, after capture in the cratonic mantle lithosphere, may be overprinted by interaction with metasomatic melts and fluids. Data are as yet sparse, but new Fe-based oxybarometry shows mantle eclogites to have highly variable fO2 (FMQ-3 to FMQ), whereby low fO2 relative to modern MORB may relate to subduction of more reducing Archaean oceanic crust or loss of ferric Fe during partial melt loss [2,3]. Indeed, using V/Sc as a redox proxy, it was recently shown that Archaean mantle eclogites are more reduced than modern MORB (ΔFMQ-1.3 vs. ΔFMQ -0.4), leading to a shallower depth of redox melting [4]. Although higher Fe contents of eclogites compared to peridotites may translate into greater robustness during metasomatism after emplacement into the cratonic lithosphere, it is possible that this is at least in part responsible for their highly variable Fe-based fO2. In order to help further constrain the redox state of mantle eclogites and unravel the effect of primary and secondary processes, we are currently measuring Fe3+/Fetotal by Mössbauer in garnet from two compositionally well-characterised mantle eclogite suites (Kaapvaal craton and West African craton), with the aim to use recently calibrated oxybarometers [2,3] to calculate fO2. The results will bear on the speciation and hence mobility of carbon during a variety of mantle processes ranging from partial melting of the convecting mantle to metamorphic reactions upon subduction and metasomatic interactions. [1] Aulbach and Jacob (in press) Lithos; [2] Stagno et al. (2015) Contrib Mineral Petrol 42: 207-219; [3] Vasilyev (2016) PhD Thesis, Australian Nat Univ; [4] Aulbach and Stagno (in press) Geology

Evidence for Primordial Water in Earths Deep Mantle: D/h Ratios in Baffin Island and Icelandic Picrites

NASA Astrophysics Data System (ADS)

Hallis, L. J.; Huss, G. R.; Nagashima, K.; Taylor, J.; Hilton, D. R.; Mottl, M. J.; Meech, K. J.; Halldorsson, S. A.

2016-12-01

Experimentally based chemical models suggest Jeans escape could have caused an increase in Earth's atmospheric D/H ratio of between a factor of 2 and 9 since the planets formation1. Plate tectonic mixing ensures this change has been incorporated into the mantle. In addition, collisions with hydrogen bearing planetesimals or cometary material after Earth's accretion could have altered the D/H ratio of the planet's surface and upper mantle2. Therefore, to determine Earth's original D/H ratio, a reservoir that has been completely unaffected by these surface and upper mantle changes is required. Most studies suggest that high 3He/4He ratios in some OIBs indicate the existence of relatively undegassed regions in the deep mantle compared to the upper mantle, which retain a greater proportion of their primordial He3-4. Early Tertiary (60-million-year-old) picrites from Baffin Island and west Greenland, which represent volcanic rocks from the proto/early Iceland mantle plume, contain the highest recorded terrestrial 3He/4He ratios3-4. These picrites also have Pb and Nd isotopic ratios consistent with primordial mantle ages (4.45 to 4.55 Ga)5, indicating the persistence of an ancient, isolated reservoir in the mantle. The undegassed and primitive nature6of this reservoir suggests that it could preserve Earth's initial D/H ratio. We measured the D/H ratios of olivine-hosted glassy melt inclusions in Baffin Island and Icelandic picrites to establish whether their deep mantle source region exhibits a different D/H ratio to known upper mantle and surface reservoirs. Baffin Island D/H ratios were found to extend lower than any previously measured mantle values (δD -97 to -218 ‰), suggesting that areas of the deep mantle do preserve a more primitive hydrogen reservoir, hence are unaffected by plate tectonic mixing. Comparing our measured low D/H ratios to those of known extra-terrestrial materials can help determine where Earths water came from. References: [1] Genda and Ikoma, 2008 Icarus 194, 42-52. [2] Abramov, and Mojzsis, (2009) Nature 459, 419-422. [3] Stuart et al. (2003) Nature 424, 57-59. [4] Starkey et al. (2009) Earth Planet. Sci. Lett. 277, 91-100. [5] Jackson et al. (2010) Nature 466, 853-856. [6] Robillard et al. (1992) Contrib. Mineral. Petrol. 112, 230-241.

Nano-scale Characterization of Basalt - Quenched Lava and Reheated Products

NASA Astrophysics Data System (ADS)

Burkhard, D. J.; Wirth, R.

2001-12-01

In order to trace the mechanism of crystallization in basalt we investigated basalt lava from active Pu'u O'o, Kilauea, Hawaii with TEM. We considered (1) quenched melt (glass, obtained by dipping a hammer into the lava (April 1996) and subsequent quenching in air), and (2) that glass after reheating for 48 hr at 850° C, and (3) after reheating for 48 hr at 930° C. Previous investigations had illustrated interface-controlled growth of pyroxene and Fe-Ti oxides at 850° C and volumetric growth of these phases in addition to plagioclase above 920° C [1]. In general, (1) is a perfect glass to the nano-scale. Occasional inhomogeneities are identified as plagioclase. With a size of no more than approximately 100 unit cells, these "crystals" might be considered as nuclei. Dendrites of pyroxene, identified on the micron scale with back scattered electrons [1], occur as a sequence of slightly displaced plates with equal orientation on the nano-scale. HREM, diffraction pattern and EDS confirm that this is augite, in agreement with investigations on the micron-scale [1]. Fe-Ti oxides occur isolated in the matrix with a diameter less than 100 nm, in contrast to the micron-scale, where Fe-Ti oxides appear at the apices of augite. In (3) we find in addition plagioclase with thin lamellae, indicating twinning. In (3),augite contains lamellae parallel to (001), and they are identified as pigeonite by HREM and electron diffraction. Pigeonite lamellae occur also in (2), however, less developed. Electron diffraction suggests that reflections of augite correspond to the space group C 2/c, and of exsolved pigeonite to P 21/c, which is a low pigeonite. These exsolution phenomena are undistiguishable from what is usually observed in relation to high cooling rates [e.g. 2]. The stability of pigeonite at these temperatures suggests a Fe/Fe+Mg ratio above 0.6 for pyroxene in the quadilateral [3]. Microprobe analyses [1] suggest ratios of 0.4 to 0.5. [1] Burkhard D.J.M. (2001) J. Petrol. 42, 507-527; [2] Philpotts A.R. (1990) Principles of Igneous and Metamorphic Petrology, Prentice; [3] Lindsley A.(1983) Am. Mineral. 68, 477-493.

Aqueous Alteration of Tridymite: Implications for its Discovery at Gale Crater, Mars

NASA Astrophysics Data System (ADS)

Rampe, E. B.; Morris, R. V.; Ming, D. W.; Graff, T. G.; Downs, R. T.; Peretyazhko, T.

2016-12-01

Tridymite is a high-temperature, low-pressure polymorph of SiO2. It is relatively uncommon on Earth and can form by vapor phase alteration of silicic tuffs [e.g., 1], in silicic volcanic fumaroles [e.g., 2], and from contact metamorphism of opaline silica [e.g., 3]. The martian crust is generally mafic, and minerals that form in silicic volcanic environments are rarely observed from orbit [e.g., 4]. The Mars Science Laboratory Curiosity has been investigating an ancient fluviolacustrine sequence in Gale crater since its landing in August 2012. Monoclinic tridymite was recently discovered with X-ray diffraction data measured by the CheMin instrument in a target called Buckskin drilled from the Murray formation in the Marias Pass area [5,6]. The Murray fm is dominated by finely horizontally laminated mudstone, suggesting subaqueous sediment deposition in a lake. Buckskin contains substantial amounts of tridymite (13.6 wt.% of the bulk sample) and abundant X-ray amorphous materials (60 wt.%), primarily made up of high-silica phases (opal-A, opal-CT, obsidian) [5]. Other samples drilled from the Murray fm contain minerals consistent with diagenesis by acid-sulfate solutions (e.g., jarosite, hematite) [7], and geochemical trends in the Marias Pass and Pahrump Hills sections suggest these sediments were altered by acidic fluids in an open system [7]. The stability and alteration products of tridymite in acid-sulfate alteration environments are not well characterized. To investigate the behavior of tridymite in these environments, we performed a series of laboratory experiments in which we exposed synthetic tridymite (monoclinic) to 0.5 and 2 M solutions of H2SO4 for up to three weeks at 25 °C and 150 °C. Our experiments show that tridymite is stable in these environments, suggesting that tridymite in the lacustrine sediments found in Marias Pass would have survived diagenesis in acidic solutions. Future experiments will include alteration under neutral and alkaline conditions to further explore the stability of tridymite in aqueous environments. [1] Broxton et al. (1995) LANL Lab Rept. LA-12934-MS. [2] Hamasaki (2002) Earth Planet Sp, 54. [3] Del Moro et al. (2011) J. Petrol., 52. [4] Smith and Bandfield (2012) JGR, 117. [5] Morris et al. (2016) PNAS, 113. [6] Morris et al., this meeting. [7] Rampe et al. (2016) LPS XLVII.

Vapor Saturation as The Cause of Volcanic Eruptions at the Lassen Volcanic Center, California, as Inferred from Crystallization Pressures and Temperatures

NASA Astrophysics Data System (ADS)

De Los Reyes, A. M. A.; Putirka, K. D.; Clynne, M. A.; Scruggs, M. A.

2015-12-01

The last three silicic eruptions at the Lassen Volcanic Center occurred at Lassen Peak (27 ka and 1915-17) and Chaos Crags (1103 yrs BP). Klemetti and Clynne (2014) showed that felsic eruptions at Lassen reflect remobilization of resident rhyodacitic crystal mush by intrusion of mafic magma. To better understand the rejuvenation and eruption triggering process, we calculate crystallization temperatures and pressures from clinopyroxene-liquid equilibria on mafic enclaves that provide our closest approach to the composition of mafic magmas delivered to the shallow system. Our goal is to examine whether and to what extent cooling and crystallization occur after recharge, which bears on whether recharge, mixing, or partial crystallization (and consequent vapor saturation) provide the trigger for eruption. We use results from the cpx-liq barometer (1.7 kbar) as input to calculate T for other phases (plagioclase, olivine and amphibole) found in mafic enclave samples. Cpx crystallizes at 1100-1150 oC and olivine precipitates at similar to slightly higher temperatures. Cpx and ol are followed by plagioclase (1000-1050 oC), amphibole (875-1000 oC), and Fe-Ti oxides (1030-1050 oC). These temperatures indicate that recharge magmas are incompletely crystallized as they enter the shallow reservoir of cooler (~725-750 oC, Quinn et al., 2013) felsic crystal mush, and that significant cooling of the mafic magma occurs during mixing and prior to eruption. Such cooling intervals indicate that recharge is not the proximal cause of eruption, but rather that vapor saturation, following a period of mixing and cooling, leads to increased magma overpressure that causes eruption. Interestingly, the Lassen Peak 27 ka volcanics (at 2.09 km3), have a greater volume than either of Chaos Crags (1.2 km3) and the 1915 (0.03 km3) eruption, but our results indicate that their thermal histories are similar. This suggests that while volumes of mafic recharge may control the degree of interaction with felsic crystal mush (e.g., Clynne, 1999), and eventually the volume of erupted magma, recharge volumes do not affect eruption triggering mechanisms. Clynne MA (1999) J. Petrol, 40: 105-132.Klemetti and Clynne, 2014, PLoS One (/12:e113157. doi10.1371/journal.pone0113157)Quinn et al., 2013, AGU Fall Annual Meeting V23C-2848

A high-resolution historical sediment record of nutrients, trace elements and organochlorines (DDT and PCB) deposition in a drinking water reservoir (Lake Brêt, Switzerland) points at local and regional pollutant sources.

PubMed

Thevenon, Florian; de Alencastro, Luiz Felippe; Loizeau, Jean-Luc; Adatte, Thierry; Grandjean, Dominique; Wildi, Walter; Poté, John

2013-03-01

The (137)Cs and (210)Pb dating of a 61-cm long sediment core retrieved from a drinking water reservoir (Lake Brêt) located in Switzerland revealed a linear and relatively high sedimentation rate (~1 cm year(-1)) over the last decades. The continuous centimeter scale measurement of physical (porewater and granulometry), organic (C(org), P, N, HI and OI indexes) and mineral (C(min) and lithogenic trace elements) parameters therefore enables reconstructing the environmental history of the lake and anthropogenic pollutant input (trace metals, DDT and PCBs) at high resolution. A major change in the physical properties of the lowermost sediments occurred following the artificial rise of the dam in 1922. After ca. 1940, there was a long-term up-core increase in organic matter deposition attributed to enhance primary production and anoxic bottom water conditions due to excessive nutrient input from a watershed predominantly used for agriculture that also received domestic effluents of two wastewater-treatment plants. This pattern contrasts with the terrigenous element input (Eu, Sc, Mg, Ti, Al, and Fe) which doubled after the rising of the dam but continuously decreased during the last 60 years. By comparison, the trace metals (Cu, Pb and Hg) presented a slight enrichment factor (EF) only during the second part of the 20th century. Although maximum EF Pb (>2) occurred synchronously with the use of leaded gasoline in Switzerland (between ca. 1947 and 1985) the Hg and Cu profiles exhibited a relatively similar trend than Pb during the 20th century, therefore excluding the alkyl-lead added to petrol as the dominant (atmospheric) source of lead input to Lake Brêt. Conversely, the Cu profile that did not follow the decrease registered in Pb and Hg during the last 10 years, suggests an additional source of Cu probably linked to the impact of agricultural activities in the area. In absence of heavy industries in the catchment, the atmospheric deposition of DDT and PCBs via surface runoff followed the historical emissions of POPs in Switzerland. Such result highlights the regional contamination of freshwater resources by the large-scale emission of toxic industrial chemicals in the 1960s and 1970s as well as the efficiency of the regulatory measures subsequently taken. Copyright © 2012 Elsevier Ltd. All rights reserved.

Evidence of Arc Magma Genesis in a Paleo-Mantle Wedge, the Higashi-Akaishi Peridotite, Japan

NASA Astrophysics Data System (ADS)

Till, C. B.; Guild, M. R.; Grove, T. L.; Carlson, R. W.

2014-12-01

Located in the Sanbagawa subduction-related high-pressure metamorphic belt in SW Japan on the island of Shikoku, the Higashi-akaishi peridotite body is composed of dunite, lherzolite and garnet clinopyroxenite, interfingered in one locality with quartz-rich eclogite. Previous work indicates the P-T history of the peridotite includes rapid prograde metamorphism with peak temperatures of 700-810°C and pressures of 2.9-3.8 GPa [1] at ~88-89 Ma followed by rapid exhumation at >2.5 cm/yr [2,3]. Major and trace element and isotopic data from samples within the Higashi-akaishi peridotite presented here and in another recent study [4] provide a record of subduction zone melting processes in a paleo-mantle wedge. Ultramafic samples range from 40-52 wt.% SiO2, 1-11 wt.% Al2O3 and 21-45 wt.% MgO with olivine and clinopyroxene Mg#'s as high as 0.93. The quartz-rich eclogite contains 62 wt.% SiO2, 6 wt.% MgO and 13 wt.% Al2O3 with trace element concentrations that are enriched relative to the ultramafic samples. 87Sr/86Sr (.703237-.704288), 143Nd/144Nd (ɛNd=+2 to +6) and Pb isotopic compositions are within the range of previously studied Japanese arc rocks. We interpret the pyroxenites as shallowly crystallized cumulates with varying amounts of trapped hydrous melt and the harzburgites as residues of melting. The peak P-T conditions of these rocks are similar to the solidus conditions of H2O-saturated fertile mantle near the base of the mantle wedge [5,6]. The presence of garnet porphyroblasts that enclose primary euhedral chlorite together with the chemical evidence, suggest these samples are associated with mantle melting in the presence of H2O. Major element modeling suggests the quartz-rich eclogite composition can be reproduced through mixing melts of subducted sediment with wet peridotite melts in the mantle wedge. Thus the Higashi-aikashi rock suite provides an in-situ record of the beginnings of hydrous melting and the mechanisms of metasomatism in the mantle wedge. [1] Enami et al. (2004) J. Meta. Geol. 22, 1-15. [2] Okamoto et al. (2004) Terra Nova 16, 81-89. [3] Wallis et al. (1990) J. Meta. Geol. 27, 93-105. [4] Hattori et al. (2010) Island Arc 19, 192-207. [5] Grove et al. (2006) Earth Planet. Sci. Lett. 249, 74-89. [6] Till et al. (2012) Cont. Min. Petrol. 163, 669-688.

Sulfides in the Garnet Pyroxenite xenoliths from Oahu, Hawaii

NASA Astrophysics Data System (ADS)

Sen, I. S.; Sen, G.; Bizimis, M.

2007-12-01

Oahu is known for its garnet bearing xenoliths that occur in the Honolulu Volcanics. Clinopyroxene is the dominant minerals of these rocks, and modes of other silicate minerals - orthopyroxene, olivine, garnet, amphibole, and phlogopite vary considerably. Ilmenite and Spinels of diverse variety also occur (Keshav et al. 2007, J. Petrol.). In this report we present new electron microprobe and LA-ICPMS data on the sulfides that are always present in these xenoliths although they make up only trace amounts. In terms of morphology and mode of occurrence the sulfides can be divided fundamentally into two types - Type I occurs as poikilitic inclusions in the silicate phases mostly in clinopyroxene and Type II occurs in the interstitial spaces between the silicates, along grain boundaries and along cracks within individual silicate grains. Sizes of both types vary considerably. Type I sulfides are generally globular and appear to have formed from immiscible sulfide melts that got enclosed by the silicate minerals that grew from the main body of silicate melt. Keshav et al. (2007) estimate the average solidus temperatures of garnet pyroxenites from Oahu to range from 1215 to 1600°C (average 1325°C) at 3-5 GPa. Therefore, the Type I sulfides are high temperature sulfides that formed above the silicate solidus. Type II sulfides take various forms - from vein-like to dendritic. Compositionally, both types include Ni rich pyrrhotites (Ni content varies from 3-5 wt%) and monosulfide solid solutions(MSS). The MSS are divided into Ni rich MSS containing as much as 20 wt% of Ni, the average is 15 wt% while the Ni poor MSS has 5-9 wt% of Ni in it. We have limited data on PGE so far but the Type II sulfides have a very low PGE content. Two recent papers have noted that Hawaiian plume-derived shield tholeiites are too rich in Ni for a given SiO2% to be produced by partial melting of a peridotite and called for an unusual Ni-rich pyroxenite source in which the large Ni content is locked in clinopyroxene. The many experiments that have been conducted on pyroxenites have not been able to generate such high Ni clinopyroxenes. We propose that the Ni actually comes from the high Ni monosulfide solid solutions similar to those in the pyroxenites studied. However, we do not think that these pyroxenites are the source of Hawaiian shield lavas because their isotopic composition is distinct from shield lavas.

A New Carbonate Chemistry in the Earth's Lower Mantle

NASA Astrophysics Data System (ADS)

Boulard, E.; Gloter, A.; Corgne, A.; Antonangeli, D.; Auzende, A.; Perrillat, J.; Guyot, F. J.; Fiquet, G.

2010-12-01

The global geochemical carbon cycle involves exchange between the Earth’s mantle and the surface. Carbon (C) is recycled into the mantle via subduction and released to the atmosphere via volcanic outgassing. Carbonates are the main C-bearing minerals that are transported deep in the Earth’s mantle via subduction of the oceanic lithosphere [1]. The way C is recycled and its contribution to the lower mantle reservoir is however largely unknown [ e.g 2, 3]. In this respect, it is important to assess if carbonates can be preserved in the deep mantle, or if decarbonatation, melting or reduction play a role in the deep carbon cycle. To clarify the fate of carbonates in the deep mantle, we carried out high-pressure and high-temperature experiments up to 105 GPa and 2850 K. Natural Fe-Mg carbonates or oxide mixtures of (Mg,Fe)O + CO2 were loaded into laser heated diamond anvil cells. In situ characterizations were done by X-ray Diffraction (XRD) using synchrotron radiation at the high-pressure beamline ID27 of the European Synchrotron Radiation Facility. A focused ion beam technique was then used to prepare the recovered samples for electron energy loss spectroscopy in a dedicated scanning transmission electron microscope (EELS-STEM) and scanning transmission X-ray microscopy (STXM). In situ XRD clearly shows the transformation of the initial carbonate phase into a new Mg-Fe high pressure carbonate phase at lower mantle conditions. We also provide direct evidence for recombination of CO2 with (Mg,Fe)O to form this new carbonate structure. In addition, subsequent EELS-STEM and STXM spectroscopies carried out on recovered samples yields C K-edge and stoechiometry characteristic to this new carbonate structure. This new high pressure phase concentrates a large amount of Fe(III), as a result of redox reactions within the siderite-rich carbonate. The oxidation of iron is balanced by partial reduction of carbon into CO groups and/or diamond. These reactions may provide an explanation for the coexistence of oxidized and reduced C species observed on natural samples [4, 5], but also a new diamond formation mechanism at lower mantle conditions. [1] Sleep, N. H., and K. Zahnle (2001) J. Geophys. Res.-Planets 106(E1), 1373-1399. [2] Javoy, M. (1997) Geophys. Res. Lett. 24(2), 177-180. [3] Lecuyer et al. (2000) Earth Planet. Sci. Lett. 181(1-2), 33-40. [4] Brenker et al. (2007) Earth Planet. Sci. Lett. 260(1-2), 1-9. [5] Stachel et al. (2000) Contrib. Mineral. Petrol. 140(1), 16-27.

Isotope U-Pb age on single zircon and REE distribution in rocks and zircon from paleoproterozoic Kandalaksha-Kolvitsa complex Baltic shield

NASA Astrophysics Data System (ADS)

Steshenko, Ekaterina; Bayanova, Tamara; Drogobuzhskaya, Svetlana; Lyalina, Ludmila; Serov, Pavel; Chashchin, Viktor; Elizarov, Dmitriy

2017-04-01

Kandalaksha-Kolvitsa paleoproterozoic complex located in the N-E part of Baltic shield and consists of three zones. Marginal zone (mesocratic metanorite) lies at the base of the massif. Main zone is composed of leucocratic metagabbro. The upper zone is alteration of mataanorthosite and leucocratic metagabbro. All rocks were subjected to granulate and anorthositic metamorphism. Age of magmatic crystallization of the massif was determined for the first time, using the U-Pb isotope method for single zircon grains. Three fractions of single zircons from anorthosite of the Kandalaksha massif gave precise U-Pb age of 2435.5 ± 4.8 Ma. For the first time REE concentration (WR) was determined using a quadrupole mass spectrometer (Agilent 7500 ce ICP-MS) in the main varieties of rocks of the Kandalaksha-Kolvitsa paleoproterozoic complex. Anorthosite and leucocratic metagabbros (main zone) are characterized by a flat spectrum distribution of HREE, which were normalized by [1]. The REE pattern is characterized by significant positive anomalies of Eu ((Eu / Eu *)n = 3.72-3.91) in anorthosite and leucogabbros and 7.26 - in ortoamfibolitah. General content of individual elements that are common for this type of rocks: Cen = 5.82-8.54, Ybn = 1.54-1.58, which indicates that the process of crystallization of the rock occurred with predominant accumulation of plagioclase. According to geochemical and Nd-Sr isotopic data (ISr=0.702 - 0.706, ɛNd(T) = +1 - (-3)) Kandalaksha Kolvitsa complex, appear to have a general plume source with Paleoproterozoic layered intrusions of the Baltic Shield [2] Distribution of REE (ELAN-9000 ICP-MS) in zircon have a typical magmatic species: a positive Ce, negative Eu anomaly and HREE flat spectrum. Titanium content in zircons were measured for the calculation of their crystallization temperature with 8350C. These data are evidence of magmatic origin of zircon [3]. The scientific researches are supported by RFBR (projects № 15-35-20501, № 16-05-00305, 16-05-00367, 16-05-00427) and theme of state assignment № 0231-2015-0005. References: 1. Boynton W.V. Cosmochemistry of the rare earth elements: meteorite studies // Ed. Henderson P. Rare earth element geochemistry. Amsterdam: Elsevier. 1984. P. 63-114. 2. Watson E. B., Wark D.A., Thomas J.B. Crystallization thermometers for zircon and rutile // Contrib. Miner. Petrol. 2006. V. 151. P. 413-433. 3. Hoskin P.W.O. and Schaltegger U. The Composition of zirconand igneous and metamorphic petrogenesis // Reviews in mineralogy & geochemistry. 2003. V. 53. P. 27-62.

Coal reserves and resources as well as potentials for underground coal gasification in connection with carbon capture and storage (CCS)

NASA Astrophysics Data System (ADS)

Ilse, Jürgen

2010-05-01

Coal is the energy source with the largest geological availability worldwide. Of all non-renewable energies coal and lignite accounting for 55 % of the reserves and some 76 % of the resources represent the largest potential. Reserves are those geological quantities of a mineral which can currently be mined under technically and economically viable conditions. Resources are those quantities which are either proven but currently not economically recoverable or quantities which can still be expected or explored on the basis of geological findings. The global availability of energy source does not only depend on geological and economic factors. The technical availability, e.g. mining and preparation capacities, the sufficient availability of land and sea-borne transportation as well as transloading capacities and also a political availability are required likewise. The latter may be disturbed by domestic-policy disputes like strikes or unrest or by foreign-policy disputes like embargos, trade conflicts or even tensions and wars in the producing regions. In the energy-economic discussion the reach of fossil primary energies plays a central role with the most important questions being: when will which energy source be exhausted, which impact will future developments have on the energy price, what does the situation of the other energies look like and which alternatives are there? The reach of coal can only be estimated because of the large deposits on the one hand and the uncertain future coal use and demand on the other. The stronger growth of population and the economic catching-up process in the developing and threshold countries will result in a shift of the production and demand centres in the global economy. However, also in case of further increases the geological potential will be sufficient to reliably cover the global coal demand for the next 100 years. The conventional mining of seams at great depths or of thin seams reaches its technical and economic limits. However, these otherwise unprofitable coal deposits can be mined economically by means of underground coal gasification, during which coal is converted into a gaseous product in the deposit. The synthesis gas can be used for electricity generation, as chemical base material or for the production of petrol. This increases the usability of coal resources tremendously. At present the CCS technologies (carbon capture and storage) are a much discussed alternative to other CO2 abatement techniques like efficiency impovements. The capture and subsequent storage of CO2 in the deposits created by the actual underground gasification process seem to be technically feasible.

IR spectroscopic determination of OH defects in spinel group minerals

NASA Astrophysics Data System (ADS)

Halmer, M. M.; Libowitzky, E.; Beran, A.

2003-04-01

Previous experimental studies showed that spinel phases, likely to occur in the transition zone of the Earth's mantle, contain essential amounts of water in form of OH groups. The g-Mg_2SiO_4 phase is reported to contain 27000 wt.ppm H_2O. The corresponding IR spectrum shows very broad absorption bands centered at 3645 and 3345cm-1 with a shoulder at 3120cm-1 (Kohlstedt et al., 1996). Thus, it is evident that under high-pressure conditions the spinel structure is capable to incorporate OH groups. Up to present, hydrogen contents of spinels from upper Earth's mantle and from crustal occurrences have not been reported in the literature. It is the aim of this study to prove the presence of OH defects in spinels of naturally occurring paragenesis and to develop some ideas on the structural incorporation mode based on promising results obtained from synthetic phases. Highly disordered non-stoichiometric Verneuil-grown MgAl spinels are characterized by two significant bands centered at 3355cm-1 and 3510cm-1, which show variations in band intensities. Synthetic H_ high-temperature treated intermediate compounds in the spinel-magnesioferrite (MgFe_2O_4), spinel-hercynite (FeAl2O4) and spinel-franklinite (ZnFe2O4) system from Andreozzi et al. (2001) indicate variable behavior. Whereas some of the spectra, which may be also correlated to d-d transitions of IVFe2+ (Skogby and Halenius, 2003) show broad absorptions in the 3500-3100cm-1 range, a pure MgAl2O4 end member sample is characterized by a rather sharp mode at 3450cm-1. Naturally occurring gahnite crystals (ZnAl2O_4) show significantly broad absorption band at 3400cm-1, which resembles some of the bands of the former synthetic samples. Based on the calibration of Libowitzky and Rossman (1997) the analytical H_2O content of the natural gahnite sample was determined to 580 wt.ppm. The position of the absorption bands implies weak hydrogen bonding of the OH defects in the spinel structure. This work was partly supported by the EU through the Human Potential Program HPRN-CT-2000-0056. References: Andreozzi GB, Hålenius U, Skogby H (2001). Phys Chem Minerals, 28: 435-444. Kohlstedt DL, Keppler H, Rubie DC (1996). Contr Mineral Petrol, 123: 345-357. Libowitzky E, Rossman GR (1997). Am Mineral, 82: 1111-1115. Skogby H, Hålenius U (2003). Am Mineral, (in press)

The effects of buoyancy on shear-induced melt bands in a compacting porous medium

NASA Astrophysics Data System (ADS)

Butler, S. L.

2009-03-01

It has recently been shown [Holtzman, B., Groebner, N., Zimmerman, M., Ginsberg, S., Kohlstedt, D., 2003. Stress-driven melt segregation in partially molten rocks. Geochem. Geophys. Geosyst. 4, Art. No. 8607; Holtzman, B.K., Kohlstedt, D.L., 2007. Stress-driven melt segregation and strain partitioning in partially molten rocks: effects of stress and strain. J. Petrol. 48, 2379-2406] that when partially molten rock is subjected to simple shear, bands of high and low porosity are formed at a particular angle to the direction of instantaneous maximum extension. These have been modeled numerically and it has been speculated that high porosity bands may form an interconnected network with a bulk, effective permeability that is enhanced in a direction parallel to the bands. As a result, the bands may act to focus mantle melt towards the axis of mid-ocean ridges [Katz, R.F., Spiegelman, M., Holtzman, B., 2006. The dynamics of melt and shear localization in partially molten aggregates. Nature 442, 676-679]. In this contribution, we examine the combined effects of buoyancy and matrix shear on a deforming porous layer. The linear theory of Spiegelman [Spiegelman, M., 1993. Flow in deformable porous media. Part 1. Simple analysis. J. Fluid Mech. 247, 17-38; Spiegelman, M., 2003. Linear analysis of melt band formation by simple shear. Geochem. Geophys. Geosyst. 4, doi:10.1029/2002GC000499, Article 8615] and Katz et al. [Katz, R.F., Spiegelman, M., Holtzman, B., 2006. The dynamics of melt and shear localization in partially molten aggregates. Nature 442, 676-679] is generalized to include both the effects of buoyancy and matrix shear on a deformable porous layer with strain-rate dependent rheology. The predictions of linear theory are compared with the early time evolution of our 2D numerical model and they are found to be in excellent agreement. For conditions similar to the upper mantle, buoyancy forces can be similar to or much greater than matrix shear-induced forces. The results of the numerical model indicate that bands form when buoyancy forces are large and that these can significantly alter the direction of the flow of liquid away from vertical. The bands form at angles similar to the angle of maximum instantaneous growth rate. Consequently, for strongly strain-rate dependent rheology, there may be two sets of bands formed that are symmetric about the direction of maximum compressive stress in the background mantle flow. This second set of bands would reduce the efficiency with which melt bands would focus melts towards the ridge axis.

Fe3+ partitioning during basalt differentiation on Mars: insights into the oxygen fugacity of the shergottite mantle source(s).

NASA Astrophysics Data System (ADS)

Medard, E.; Martin, A. M.; Collinet, M.; Righter, K.; Grove, T. L.; Newville, M.; Lanzirotti, A.

2014-12-01

The partitioning of Fe3+ between silicate melts and minerals is a key parameter to understand magmatic processes, as it is directly linked to oxygen fugacity (fO2). fO2 is, a priori, not a constant during magmatic processes, and its evolution depends on the compatibility of Fe3+. We have experimentally determined the partition coefficients of Fe3+ between augite, pigeonite, and silicate melt, and use them to constrain the fO2of the martian mantle and of differentiated martian basalts. A series of experiments on various martian basaltic compositions were performed under controlled fO2 in one-atmosphere gas-mixing furnaces. Fe3+/Fetotal ratios in silicate melts and pyroxenes were determined using synchrotron Fe K-edge XANES on the 13 IDE beamline at APS (Argonne). Fe3+ mineral/melt partition coefficients (DFe3+) for augite and pigeonite were obtained with a relative uncertainty of 10-15 %. Both are constant over a wide range of oxygen fugacity (FMQ-2.5 to FMQ+2.0). DFe3+ for augite and pigeonite are broadly consistent with previous data by [1], but DFe3+ for augite is significantly higher (by a factor of 2) than the indirect determinations of [2]. Since augites in [2] are extremely poor in iron compared to ours (0.18 wt% vs 13 wt% FeO), this strongly suggests that DFe3+ varies with Mg#, indicating that Fe3+is more compatible than previously thought in terrestrial mantle pyroxenes (3 wt% FeO) as well. Crystallization paths for shergottite parental melts have been calculated using the MELTS software, combined with our partition coefficients. fO2 in the residual melts is calculated from the models of [3] and [4]. It stays relatively constant at high temperatures, but increases very strongly during the latest stages of crystallization. These results explain the large range of fO2 determined in enriched shergottites. In order to estimate the fO2 of the martian mantle, only the highest temperature phases in the most primitive martian samples should be used. The most primitive shergottites record a mantle fO2 around FMQ-2.5, consistent with the lowest fO2estimated for surface basalts [5]. [1] McCanta et al. (2004) Am Min 89:1685-1693; [2] Mallmann and O'Neill (2009) J Petrol 50:1765-1794; [3] Righter et al. (2013) Am Min 98:616-628; [4] Kress and Carmichael (1991) CMP 108:82-92; [5] Schmidt ME et al. (2014) EPSL 384:198-208.

The association between exposure to environmental factors and the occurrence of attention-deficit/hyperactivity disorder (ADHD). A population-based retrospective cohort study.

PubMed

Saez, Marc; Barceló, Maria A; Farrerons, Mònica; López-Casasnovas, Guillem

2018-06-08

A number of factors contribute to attention deficit hyperactivity disorder (ADHD) and although they are not fully known, the occurrence of ADHD seems to be a consequence of an interaction between multiple genetic and environmental factors. However, apart from pesticides, the evidence is inadequate and inconsistent as it differs not only in the population and time period analysed, but also in the type of study, the control of the confounding variables and the statistical methods used. In the latter case, the studies also differ in the adjustment of spatial and temporal variability. Our objective here, is to provide evidence on an association between environmental factors and ADHD. In our study, we used a population-based retrospective cohort in which we matched cases and controls (children free of the disease) by sex and year of birth (n = 5193, 78.9% boys). The cases were children born between 1998 and 2012 and diagnosed with ADHD (n = 116). To evaluate whether there was a geographical pattern in the incidence of ADHD, we first represented the smoothed standardized incidence rates on a map of the region being studied. We then estimated the probability of being a case by using a generalized liner mixed model with a binomial link. As explanatory variables of interest, we included the following environmental variables: distance to agricultural areas, distance to roads (stratified into three categories according to traffic density and intensity), distance to petrol stations, distance to industrial estates, and land use. We control for both observed (individual and family specific variables and deprivation index) and unobserved confounders (in particular, individual and familial heterogeneity). In addition, we adjusted for spatial extra variability. We found a north-south pattern containing two clusters (one in the centre of the study region and another in the south) in relation to the risk of developing ADHD. The results from the multivariate model suggest that these clusters could be related to some of the environmental variables. Specifically, living within 100 m from an agricultural area or a residential street and/or living fewer than 300 m from a motorway, dual carriageway or one of the industrial estates analysed was associated (statistically significant) with an increased risk of ADHD. Our results indicate that some environmental factors could be associated with ADHD occurring, particularly those associated with exposure to pesticides, organochlorine compounds and air pollutants because of traffic. Copyright © 2018 Elsevier Inc. All rights reserved.

Lead isotope constraints on the origin of andesite and dacite magmas at Tungurahua volcano (Ecuador)

NASA Astrophysics Data System (ADS)

Nauret, Francois; Ancellin, Marie-Anne; Vlastelic, Ivan; Tournigand, Pierre-Yves; Samaniego, Pablo; Le Pennec, Jean Luc; Gannoun, Mouhcine; Hidalgo, Silvana; Schiano, Pierre

2016-04-01

Understanding the occurrence of large explosive eruptions involving silica-rich magmas at mostly andesitic volcanoes is crucial for volcanic hazard assessment Here we focus on the well-known active Tungurahua volcano (Ecuador), specifically its eruptive sequence for the last 3000 years BP, which are characterized by VEI 3 explosive events involving mostly homogeneous andesitic compositions (56-59 wt.% SiO2). However, some large eruptions (VEI ≥ 4) involving andesitic and dacitic magmas (up to 66 wt.% SiO2) also occur at 3000 BP, 1250 BP and 1886 AD. An additional outburst of siliceous magmas occurred during the last eruptive eruption of this volcano in 2006 [1]. Volcanic products at Tungurahua are described as been generated by a binary mixing between a silica-rich and a silica-poor end-member, but the origin of these components was not discussed [2]. Major, trace elements and Sr-Nd-Pb isotopes were used to investigate the genesis of the andesites and dacites. Andesites are heterogeneous in terms of Pb isotopes (206Pb/204Pb: 18.189-19.154, 207Pb/204Pb:15.658-15.696, 208Pb/204Pb: 38.752-38.918, 207Pb/206Pb: 0.8240-0.8275) but homogeneous in terms of major-trace element. Dacite are characterized by homogenous and low 207Pb/206Pb (0.8235±0.0001), very low Nb/U (1.97 to 4.49) and Ce/Pb (2.52-2.99) and high Th/La ratios (0.24 to 0.49). Triangular distribution of data in major element or trace element ratio vs. Pb isotopes plots suggests that at least three components control geochemical variability at Tungurahua. We interpret andesite compositions as reflecting mainly a deep mixture of two mantle components, with small addition of crustal material. We suggest that dacite results from a mixing between various andesite compositions and a larger amount of a contaminant derived from the volcanic basement of the Tungurahua made of late Cretaceous to Palaeogene oceanic plateau basalts and volcano-sedimentary rocks volcanic. Since andesite and dacite occur during the same eruption, we suggest that crustal contaminated magmas are stored into the crust and are sporadically sampled by andesite magmas ascending from greater depths.. As a result, the amount of assimilated crust (and thus the amount of silica-rich magma) may be used as a proxy of the magnitude of the eruption. [1] Samaniego et al. JVGR (2011) [2] Schiano, P., et al. Contrib. Mineral. Petrol. 160(2010) 297-312.

40Ar-39Ar age clustering in the active phonolitic Cadamosto Seamount (Cape Verdes): Indications for periodic magmatic activity

NASA Astrophysics Data System (ADS)

Samrock, L. K.; Hansteen, T. H.; Wartho, J. A.

2017-12-01

The Cape Verde archipelago is situated 400-800 km off the west coast of Africa and is comprised of a northern and southern chain of islands and seamounts. Morphological observations and previous radiometric dating of the islands indicate a slow age progression, over 22 Ma, from east to west (Holm et al. 2008). We present the first radiometric ages for Cadamosto Seamount, which is composed of complex evolved volcanics and is situated at the southwestern tip of the Cape Verde archipelago (e.g. Barker et al. 2012). We analyzed five different submarine phonolites that were sampled by remotely operated vehicles (ROV) Kiel 6000 and dredging during the RV Meteor (M80/3) and RV Poseidon (POS320/2) cruises. Fresh sanidine, nepheline, and biotite grains were selected and carefully prepared for 40Ar-39Ar single grain total fusion analysis. Sanidine single grain 40Ar-39Ar ages from 5 samples range from 11.5 ± 6.5 ka to 349.0 ± 20.4 ka (2σ errors), and cluster in several age groupings (using the decay constant and atmospheric air ratio of Steiger & Jäger (1977), and age standard TCS2 (27.87 ± 0.04 Ma; 1σ; M.A. Lanphere, pers. comm.)). Three age groups can be identified within the youngest (0-170 ka) sanidines, which are separated by periods of 52-54 ka. Nepheline grains from one sample yielded much older ages of 169.5 ± 16.5 ka to 1521.5 ± 8.3 ka (2σ). Our data suggests young ages for the Cadamosto Seamount, which is in accordance with recorded seismic activity (Grevemeyer et al. 2010), and its position adjacent to the recently active islands of Fogo (last eruption in 2014/2015) and Brava (recent seismic activity). The different sub-groups of sanidine 40Ar-39Ar ages can be used to identify different activity maxima corresponding to cycles of magmatic productivity in a long-lived magmatic system. Ongoing petrologic investigations will be used to identify the relative importance of processes such as mantle melting rates, magma replenishment and magma chamber processes. References:Barker A.K. et al. (2012) Contrib. Mineral. Petrol. 163, 949-965. Grevemeyer I. et al. (2010) Geophys. J. Int. 180, 552-558. Holm P.M. et al. (2008) J. Geophys. Res. 113, doi:10.1029/2007JB005339, 2008. Steiger R.H., Jäger E. (1977) Earth Planet. Sci. Lett. 36, 359-362.

Ethyl tertiary-butyl ether: a toxicological review.

PubMed

McGregor, Douglas

2007-05-01

A number of oxygenated compounds (oxygenates) are available for use in gasoline to reduce vehicle exhaust emissions, reduce the aromatic compound content, and avoid the use of organo-lead compounds, while maintaining high octane numbers. Ethyl tertiary-butyl ether (ETBE) is one such compound. The current use of ETBE in gasoline or petrol is modest but increasing, with consequently similar trends in the potential for human exposure. Inhalation is the most likely mode of exposure, with about 30% of inhaled ETBE being retained by the lungs and distributed around the body. Following cessation of exposure, the blood concentration of ETBE falls rapidly, largely as a result of its metabolism to tertiary-butyl alcohol (TBA) and acetaldehyde. TBA may be further metabolized, first to 2-methyl-1,2-propanediol and then to 2-hydroxyisobutyrate, the two dominant metabolites found in urine of volunteers and rats. The rapid oxidation of acetaldehyde suggests that its blood concentration is unlikely to rise above normal as a result of human exposure to sources of ETBE. Single-dose toxicity tests show that ETBE has low toxicity and is essentially nonirritant to eyes and skin; it did not cause sensitization in a maximization test in guinea pigs. Neurological effects have been observed only at very high exposure concentrations. There is evidence for an effect of ETBE on the kidney of rats. Increases in kidney weight were seen in both sexes, but protein droplet accumulation (with alpha(2u)-globulin involvement) and sustained increases in cell proliferation occurred only in males. In liver, centrilobular necrosis was induced in mice, but not rats, after exposure by inhalation, although this lesion was reported in some rats exposed to very high oral doses of ETBE. The proportion of liver cells engaged in S-phase DNA synthesis was increased in mice of both sexes exposed by inhalation. ETBE has no specific effects on reproduction, development, or genetic material. Carcinogenicity studies have been conducted with ETBE, TBA, and ethanol (included in this review as an endogenous precursor of acetaldehyde in the absence of TBA). A single experiment with ETBE in rats and several experiments with ethanol in rats and mice were not considered adequate for an evaluation of ETBE carcinogenicity. In male rats only, TBA induced alpha(2u)-globulin nephropathy-related renal tubule adenomas. These are generally considered to have no human relevance. In addition, increases in thyroid follicular cell adenoma incidence were associated with TBA treatment in female mice. This result lacks independent confirmation and is not supported by experiments in which similar or higher internal doses of TBA were delivered.

Compositional dependent partial molar volume and compressibility of CO2 in rhyolite, phonolite and basalt glasses

NASA Astrophysics Data System (ADS)

Lerch, P.; Seifert, R.; Malfait, W. J.; Sanchez-Valle, C.

2012-12-01

Carbon dioxide is the second most abundant volatile in magmatic systems and plays an important role in many magmatic processes, e.g. partial melting, volatile saturation, outgassing. Despite this relevance, the volumetric properties of carbon-bearing silicates at relevant pressure and temperature conditions remain largely unknown because of considerable experimental difficulties associated with in situ measurements. Density and elasticity measurements on quenched glasses can provide an alternative source of information. For dissolved water, such measurements indicate that the partial molar volume is independent of compositions at ambient pressure [1], but the partial molar compressibility is not [2, 3]. Thus the partial molar volume of water may depend on melt composition at elevated pressure. For dissolved CO2, no such data is available. In order to constrain the effect of magma composition on the partial molar volume and compressibility of dissolved carbon, we determined the density and elasticity for three series of carbon-bearing basalt, phonolite and rhyolite glasses, quenched from 3.5 GPa and relaxed at ambient pressure. The CO2 content varies between 0 to 3.90 wt% depending on the glass composition. Glass densities were determined using the sink/float method in a diiodomethane (CH2I2) - acetone mixture. Brillouin measurements were conducted on relaxed and unrelaxed silicate glasses in platelet geometry to determine the compressional (VP) and shear (VS) wave velocities and elastic moduli. The partial molar volume of CO2 in rhyolite, phonolite and basalt glasses is 25.4 ± 0.9, 22.1 ± 0.6 and 26.6 ±1.8 cm3/mol, respectively. Thus, unlike for dissolved water, the partial molar volume of CO2 displays a resolvable compositional effect. Although the composition and CO2/carbonate speciation of the phonolite glasses is intermediate between that of the rhyolite and basalt glasses, the molar volume is not. Similar to dissolved water, the partial molar bulk modulus of CO2 displays a strong compositional effect. If these compositional dependencies persist in the analogue melts, the partial molar volume of dissolved CO2 will depend on melt composition, both at low and elevated pressure. Thus, for CO2-bearing melts, a full quantitative understanding of density dependent magmatic processes, such as crystal fractionation, magma mixing and melt extraction will require in situ measurements for a range of melt compositions. [1] Richet, P. et al., 2000, Contrib Mineral Petrol, 138, 337-347. [2] Malfait et al. 2011, Am. Mineral. 96, 1402-1409. [3] Whittington et al., 2012, Am. Mineral. 97, 455-467.

X-ray topographic study of diamonds: implications for the genetic nature of inclusions in diamond

NASA Astrophysics Data System (ADS)

Agrosì, Giovanna; Nestola, Fabrizio; Tempesta, Gioacchino; Bruno, Marco; Scandale, Eugenio; Harris, Jeff W.

2014-05-01

In recent years, several studies have focused on the growth conditions of the diamonds through the analysis of the mineral inclusions trapped in them (Howell, 2012 and references therein). Nevertheless, to obtain rigorous information about chemical and physical conditions of diamond formation, it is crucial to determine if the crystallization of the inclusions occurred before (protogenetic nature), during (syngenetic nature) or after (epigenetic nature) the growth of diamond (Wiggers de Vries et al., 2011). X-ray topography (XRDT) can be a helpful tool to verify the genetic nature of inclusions in diamond. This technique characterizes the extended defects and reconstructs the growth history of the samples (Agrosì et al., 2013 and references therein) and, consequently contributes to elucidation of the relationship between the inclusions and the host-diamond. With this aim a diamond from the Udachnaya kimberlite, Siberia, was investigated. The diamond crystal was the one previously studied by Nestola et al. (2011) who performed in-situ crystal structure refinement of the inclusions to obtain data about the formation pressure. The inclusions were iso-oriented olivines that did not show evident cracks and subsequently could not be considered epigenetic. Optical observations revealed an anomalous birefringence in the adjacent diamond and the inclusions had typical "diamond-imposed cubo-octahedral" shape for the largest olivine. The diffraction contrast study shows that the diamond exhibits significant deformation fields related to plastic post growth deformation. The crystallographic direction of strains was established applying the extinction criterion. Section topographs were taken to minimize the overlapping of the strain field associate with the different defects and revealed that no dislocations nucleated from the olivine inclusions. Generally, when a solid inclusion has been incorporated in the growing crystal, the associated volume distortion can be minimized by means the nucleation of dislocations and/or twinning (Agrosì et al., 2013). In our case, the specific and significant features - the olivine inclusions showing a "diamond imposed cubo-octahedral shape" and no dislocation nucleation - that characterize this sample will be discussed in detail. References: F Nestola, P Nimis, L Ziberna, M Longo, A Marzoli, JW Harris, MH Manghnani (2011): Earth and Planetary Science Letters 305 (1), 249-255. Howell, D. (2012): Eur. J. Mineral., 24, 575-585. Wiggers de Vries D.F., Drury M.R., de Winter D.A. M., Bulanova G P., Pearson D. G., Davies G. R. (2011): Contrib. Mineral. Petrol. 161, 565-579. Agrosì G., Tempesta G., Scandale E., Harris J.W. (2013): Eur. J. Mineral, 25 (4), 551-559.

Petrology and Geochronology of Kaula Volcano lavas: An off-axis window into the Hawaiian Mantle Plume

NASA Astrophysics Data System (ADS)

Garcia, M. O.; Weis, D.; Jicha, B. R.; Tree, J. P.; Bizimis, M.

2014-12-01

The Hawaiian Islands extend NW for 625 km from Lō'ihi to Ka'ula island. One anomalous feature cross-cutting the Hawaiian Islands is the Kaua'i Ridge, a 165 km-long bathymetric high with three well-defined gravity highs. These gravity highs are centered under or near the islands of Ka'ula, Ni'ihau and Kaua'i, and represent the cores of three shield volcanoes whose volumes decrease dramatically with distance from the axis of the Hawaiian Chain (Kaua'i, 58 x 103 km3, Ni'ihau x 103 km, Ka'ula 10 x 103 km; Robinson and Eakins 2006). Ka'ula Volcano, on the SW end of the Kaua'i Ridge, is centered 100 km off the axis of the Hawaiian mantle plume. The volcano is capped by a small island, which is a remnant of a nephelinitic tuff cone. The cone contains abundant accidental bombs of lava (tholeiite, phonolite and basanite), peridotite and pyroxenite, and unexploded ordnance from US military bombing. Two JASON dives on the flanks of Ka'ula recovered only alkalic lavas. Three stage of Ka'ula volcanism have been identified from sampling the volcanic bombs and flanks of the volcano. These rocks were dated using 40Ar/39Ar methods for the basalts and K-Ar for the phonolites. A tholeiitic shield basalt yielded an age of 6.2 Ma, the oldest reliable age for any Hawaiian Island tholeiite. Post-shield phonolites gave ages of 4.0 to 4.2 Ma (Garcia et al., 1986) and rejuvenation stage alkalic basalts yielded ages of 1.9 to 0.5 Ma. These ages are nearly identical to those for the same stages for adjacent Ni'ihau volcano but slightly older than on Kauai, 100 km to the NE (Sherrod et al. 2007). Thus, volcanism was nearly simultaneous along Kaua'i Ridge. The new age results extend to 420 km the distance within the Hawaiian Islands that experienced coeval rejuvenated volcanism. Geochemically, the rejuvenated and tholeiitic lavas from the Kaua'i Ridge are very similar with mixed source signatures of Loa and Kea trend compositions. Mixed Loa-Kea sources have been found for many other Hawaiian volcanoes. These results indicate that the Hawaiian mantle plume was broadly homogeneous over 100 km distance but also heterogeneous on a fine scale. Garcia et al., 1986. Contr. Mineral. Petrol. 94, 461-471; Robinson and Eakins, 2006. J. Volcanol. Geotherm. Res. 151, 309-317; Sherrod et al., 2007. USGS Open-File Rept. 2007-1089.

Impact of freeway weaving segment design on light-duty vehicle exhaust emissions.

PubMed

Li, Qing; Qiao, Fengxiang; Yu, Lei; Chen, Shuyan; Li, Tiezhu

2018-06-01

In the United States, 26% of greenhouse gas emissions is emitted from the transportation sector; these emisssions meanwhile are accompanied by enormous toxic emissions to humans, such as carbon monoxide (CO), nitrogen oxides (NO x ), and hydrocarbon (HC), approximately 2.5% and 2.44% of a total exhaust emissions for a petrol and a diesel engine, respectively. These exhaust emissions are typically subject to vehicles' intermittent operations, such as hard acceleration and hard braking. In practice, drivers are inclined to operate intermittently while driving through a weaving segment, due to complex vehicle maneuvering for weaving. As a result, the exhaust emissions within a weaving segment ought to vary from those on a basic segment. However, existing emission models usually rely on vehicle operation information, and compute a generalized emission result, regardless of road configuration. This research proposes to explore the impacts of weaving segment configuration on vehicle emissions, identify important predictors for emission estimations, and develop a nonlinear normalized emission factor (NEF) model for weaving segments. An on-board emission test was conducted on 12 subjects on State Highway 288 in Houston, Texas. Vehicles' activity information, road conditions, and real-time exhaust emissions were collected by on-board diagnosis (OBD), a smartphone-based roughness app, and a portable emission measurement system (PEMS), respectively. Five feature selection algorithms were used to identify the important predictors for the response of NEF and the modeling algorithm. The predictive power of four algorithm-based emission models was tested by 10-fold cross-validation. Results showed that emissions are also susceptible to the type and length of a weaving segment. Bagged decision tree algorithm was chosen to develop a 50-grown-tree NEF model, which provided a validation error of 0.0051. The estimated NEFs are highly correlated with the observed NEFs in the training data set as well as in the validation data set, with the R values of 0.91 and 0.90, respectively. Existing emission models usually rely on vehicle operation information to compute a generalized emission result, regardless of road configuration. In practice, while driving through a weaving segment, drivers are inclined to perform erratic maneuvers, such as hard braking and hard acceleration due to the complex weaving maneuver required. As a result, the exhaust emissions within a weaving segment vary from those on a basic segment. This research proposes to involve road configuration, in terms of the type and length of a weaving segment, in constructing an emission nonlinear model, which significantly improves emission estimations at a microscopic level.

Constraints from Water on Mantle Melting and Slab Fluid Composition

NASA Astrophysics Data System (ADS)

Plank, T.; Wade, J.

2005-12-01

Water drives mantle melting and fluid migration in subduction zones, but most models for these phenomena have been developed without constraints from water measurements in arc magmas. For example, the Central American volcanic arc (CAVA) records systematic variations in La/Yb, Ba/La and d18O, and these proxies have been used to predict the extent of mantle melting during decompression [1] and water-addition [2]. Here we use water concentrations in olivine-hosted melt inclusions from arc tephra, along with estimates derived from a clinopyroxene hygrometer [3], to test different models for mantle melting and slab fluid composition along the CAVA (from Nicaragua to Costa Rica). We use Ti as a proxy for mantle melt fraction (F) and invert H2O concentrations in CAVA magmas to obtain those in the mantle source (H2Oo), as in [4]. The relationship between F and H2Oo is nominally linear for Costa Rica mantle, with wet melting productivity dF/dH2O = 30 (wt%/wt%), higher than that used in [2], but consistent with experimentally-determined and MELTS-calculated productivity at 50 degrees above the dry solidus. This predicts mantle temperature beneath Costa Rica of at least 1350°C, and allows for a small (1-2% F) decompression-melting contribution, relative to the wet melting contribution (8-20% F). The percent of wet melting correlates locally with Ba/La, but not regionally, and so the use of Ba/La as a wet melting proxy [1] should be limited to single volcanoes or clusters. The water content of the CAVA melting region varies from 2500-9000 ppm H2O but does not decrease monotonically from Nicaragua to Costa Rica as does Ba/La. The relationship between H2Oo and Ba/La is thus complex, and requires a large along-strike decrease in Ba/La and H2O/La in the slab fluids towards the southeast. Such variation appears to be driven largely by La concentration, reflecting more dilute fluids (higher H2O/La) beneath Nicaragua and more solute-rich fluids (e.g., sediment melts with high La/ H2O) beneath Costa Rica. [1] Walker, J.A., M.J. Carr, L.C. Patino, C.M. Johnson, M.D. Feigenson, R.L. Ward Contrib. Mineral. Petrol. [2] Eiler, J.M., M.J. Carr, M. Reagan, E. Stolper, 2005. Geochem. Geophys. Geosyst. [3] Plank, T., Benjamin, E., Wade, J., Grove, T.L. 2004. Fall Mtg, AGU. [4] Kelley, K., Plank, T., Newman, S., Stolper, E.M., Grove, TL, Hauri, E. 2005. JGR.

[The over the counter drugs reform in Israel--two years later].

PubMed

Vaknin, Sharona; Abadi-Korek, Ifat; Marom, Eli; Shemer, Joshua; Luxenburg, Osnat

2011-01-01

In the last two decades there has been a world wide increase in the number of drugs that are being switched from the prescription-only category to non-prescription categories. In Israel, until recently, non-prescription medicines were only permitted to be sold by a pharmacist in pharmacies. In May 2005, following amendments to the law, several non-prescription medicines which were previously sold under a pharmacist's supervision, were reclassified as general-sales-list (GSL) medicines and permitted to be displayed and sold directly off the shelves in pharmacies and in other places such as grocery stores and petrol stations. To study the change in the patterns of consumption of non-prescription drugs in Israel two years after the reform began. A representative sample of the population of Israel was chosen and interviews were conducted at two time points: before the reform commenced and two years after the beginning of the reform. Statistical processing was performed in order to examine the changes in patterns of consumption of non-prescription drugs in Israel between these two time points. In both surveys it was found that: approximately 70% of the Israeli public buys non-prescription medicines; 70% of the people interviewed said that they had been aware of the reform, but of these, about 75% continued buying nonprescription drugs from the pharmacist while 21% bought medicines off the shelves at the pharmacy and 4% purchased medications at grocery stores. The most common reasons for buying medicines off the shelves without a pharmacist were earlier knowLedge about the medication, convenience and availabiLity when the pharmacies were closed. An insignificant difference was observed for the purchase of non-prescription drugs from the different types of pharmacies: the health maintenance organizations (HMO) pharmacies continue to be the leading pharmacies from which the public purchased their non-prescription medicines, white there was a slight increase in the purchases from pharmacy chains. In the two surveys, the purchaser's personal experience was the biggest factor influencing the decision to buy a certain drug, followed by the doctor's and the pharmacist's recommendation. Only 15% thought that non-prescription medicines are not safe. Two years after the reform began no breakthrough was observed in the pattern of purchase of non-prescription medicines. Despite exposure to the reform, most Israelis continue to buy these medicines from the pharmacists. Therefore, it appears that more time will be needed for this reform to actually start making an impact and changing the habits of Israeli consumers when purchasing non-prescription drugs.

Fe Isotope Composition of Neoproterozoic Post-Glacial "Cap Dolostones"

NASA Astrophysics Data System (ADS)

Halverson, G. P.

2005-12-01

The largest variations in the Fe isotope composition in the geological record are found in sedimentary rocks, presumably as the result of redox transformations of iron during mineral precipitation, microbial processing, and diagenesis (Johnson et al., Cont. Min. Petrol., 2003). Systematic trends in the variability of the Fe isotope composition of sulfide minerals formed in ancient marine black shales broadly mirror patterns in sulfur isotope data (Δ33S, Δ34S), which are consistent with geological and other geochemical evidence for the progressive oxidation of the earth's surface during the Precambrian (Rouxel et al., Science, 2005). Therefore, the record of the Fe isotope composition of minerals formed in the marine environment appears to be a promising proxy for the redox evolution of the ocean. We have developed a method to extract the marine Fe isotope composition from carbonates in an attempt to establish higher resolution records of changes in marine redox changes than permitted by black shale geochemistry. We have applied this method to the study of ca. 635 Ma iron-rich dolostones, which are found in Neoproterozoic successions worldwide and immediately post-date a purported snowball (Marinoan) glaciation during which time the deep ocean is thought to have become anoxic (Hoffman et al., Science, 1998), allowing its Fe isotopic composition to evolve towards the composition of relatively light (δ57Fe vs. IRMM-14 ~ -0.6‰) hydrothermal iron (Beard et al., Geology, 2003). Fe isotope compositions were measured relative to IRMM-14 in medium-resolution mode on a Neptune MC-ICP-MS with a long-term external (2σ) reproducibility of < 0.04‰/amu. Preliminary data on dolomite samples from Svalbard, northern Namibia and northwest Canada show a range in δ57Fe values from -0.65 to 0.04‰, similar to the range found in siderite and Fe-rich dolomite in ancient BIFs (Johsnon et al., 2003) and to values for the Namibian cap dolostone reported by Leighton et al. (Goldschmidt abstract, 2005), but distinctly lower than altered dolostones (δ57Fe = 0.10 - 1.02‰) in a Jurassic, organic-rich mudstone (Matthews et al., GCA, 2004). It is difficult to conclude at this time whether or not the relatively low δ57Fe composition of the cap dolostones is consistent with the Beard et al. (Geology, 2003) hypothesis due to large uncertainties in the solution-mineral fractionation factors for carbonates, the potential effects of diagenesis and biological influences on dolomite precipitation, and the possibility that the Marinoan deep ocean was euxinic.

Diverse Mafic Influences on the Magmatic System of the 2.08 Ma Huckleberry Ridge Eruption, Yellowstone

NASA Astrophysics Data System (ADS)

Wilson, C. J. N.; Swallow, E. J.; Charlier, B. L. A.; Gamble, J. A.

2016-12-01

The Yellowstone Plateau Volcanic Field (YPVF) is the youngest, currently active focus of the long-lived Yellowstone-Snake River Plain (YSRP) volcanic province. This province is traditionally considered to be bimodal1, with mantle-derived olivine tholeiites providing the thermal and volatile fluxes to generate the voluminous rhyolitic volcanism that forms the initial stages at each caldera focus2. There are also lesser volumes of alkalic compositions, which define a Craters of the Moon (COM) trend1. These eruptives, dominantly trachy-basalts and -andesites but continuous to high-Ba rhyolites, are often found at the margins of the YSRP and are believed to represent small-volume magma batches derived by extreme mid-crustal fractionation of a tholeiitic parent3,4. The 2,500 km3 Huckleberry Ridge Tuff (HRT), the first of three caldera-forming eruptions at the YPVF, consists of minor fall deposits followed by three voluminous ignimbrite members: A, B and C4. The HRT was preceded and followed by the eruption of YSRP olivine tholeiites within and around the inferred caldera4. Previously identified4 aphyric scoria in HRT member B, and a newly identified juvenile mafic component in HRT member A, are however more extreme in composition than the COM magma type with SiO2 of 49.3- 59.0 wt %, Na2O+K2O 4.5-6.6 wt %, Ba to 3500 ppm, Zr to 1850 ppm and P2O5 to 1.8 wt %. This `HRT-COM' trend is parallel to but offset to higher Ba from that defined by younger surficial COM-type lava flows west of the HRT caldera. We here summarise major, trace and isotopic data from these three mafic lineages, which temporally encompass the HRT. We compare them with other data of the COM suite and evaluate interpretations for their source which range from extreme fractional crystallisation to melts from metasomatised mantle. We highlight the close spatial and temporal association of the mafic lineages, despite their distinct chemical signatures, indicating the presence of complex root zones underplating the large-scale YSRP rhyolitic body or bodies during the onset of voluminous rhyolitic volcanism in the YPVF. 1Christiansen EH, McCurry M 2009: Bull Volc 70, 251; 2Leeman WP 2008: Geol Soc Lond Spec Pub 304, 235; 3Whitaker ML et al. 2008: Bull Volc 70, 417; 4Putirka KD et al. 2009: J Petrol 50, 1639; 5Christiansen RL 2001: USGS Prof Paper 729-G.

Characteristics and mode of emplacement of gneiss domes and plutonic domes in central-eastern Pyrenees

NASA Astrophysics Data System (ADS)

Soula, Jean-Claude

Gneiss domes and plutonic granitoid domes make up almost 50% of the pre-Hercynian terrains in the Central and Eastern Pyrenees. From a structural study of the shape and internal structure of the domes and of their relationships with the enclosing rocks, it can be shown that both types of domes were emplaced diapirically during the major regional deformation phase and the peak of regional metamorphism. The study also shows that the internal structure, the overall shape and general behaviour relative to the host rocks are similar for plutonic domes and for gneiss domes. This appears to be in good agreement with H. Ramberg's (1967, Gravity Deformation and the Earth's Crust. Academic Press, London; 1970, Model studies in relation to intrusion of plutonic bodies. In: Mechanisms of Igneous Intrusion (edited by Newall, G. & Rast, N.) Geol. J. Spec. Issue2, 261-286.) model studies showing that dome or mushroom-like structures, similar to those observed, develop when there is a small viscosity ratio between the rising body and its enclosing medium. This implies a high crystal content for the granitoid magma. This crystal content has been estimated by (i) calculating the viscosity and density in natural conditions from petrological data for the magma considered as a suspension, using the model and program of J. P. Carron et al. (1978 Bull Soc. géol. Fr.20, 739-744.); (ii) using the recent results of experimental deformation of partially melted granites of I. van der Molen & M. S. Paterson (1979, Contr. Miner. Petrol.70, 299-318.) and (ii) comparing the preceding results with the data obtained by deformation experiments on rocks similar to those enclosing the domes. The minimum crystal content for the development of a dome-like structure has been, thus, estimated to about 70%, i.e. a value very close to that estimated by van der Molen & Paterson (1979) to be the critical value separating the granular framework flow from suspension-like behaviour. The effect of small variations in the viscosity of the rising body are then simulated by centrifuge experiments. These small variations appear to exert a strong control on the shape and rate of rise of the domes. They are thought to be sufficient to account for the variations in shape and structure and the level of emplacement of the different types of gneissic and plutonic domes. Finally, more complex experiments, with models built in order to simulate as closely as possible the natural structural evolution of the region as deduced from petrological and structural data, are reported. Their implications for the regional interpretation of the relationships between gneissic and plutonic domes is then discussed.

High Pb/Ce reservoir in depleted, altered mantle peridotites

NASA Astrophysics Data System (ADS)

Godard, M.; Kelemen, P.; Hart, S.; Jackson, M.; Hanghoj, K.

2005-12-01

We find consistent, high Pb/Ce in ICP-MS data for residual peridotites from the Mid-Atlantic Ridge (MAR, from ODP Leg 209), mid-ocean ridges (MOR) worldwide [1], Oman, Josephine and Trinity ophiolites, and the Jurassic Talkeetna arc. (MAR and Oman data from Montpellier; Josephine, Trinity and Talkeetna from WSU; some Pb concentrations checked by ID at WHOI). These samples have average Pb/Ce 10x primitive mantle (PM), with only 3 of 180 samples < PM. REE patterns and Ce concentration < PM in 165 of 180 samples are consistent with depletion via melt extraction, plus some magmatic refertilization. High Pb (average 3x PM, median 0.5x PM), could be due to (a) retention of Pb in residual sulfide, (b) addition of Pb in sulfide and plagioclase during `impregnation' by crystallizing melt, and/or (c) addition of Pb in sulfide and carbonate during alteration. Pb/Ce is correlated negatively with Ce concentration, suggesting a role for (a). Pb concentration is strongly correlated with Th and Nb. These elements are considered immobile during hydrothermal alteration, their correlations with Pb are positive, and Pb is > PM in many samples, all suggesting a complementary role for (b) and a limited role for (c). All samples except Talkeetna have Th/Pb < PM. All samples except some MOR peridotites also have U/Pb < PM. DRILLED MAR peridotites show U/Pb > PM in shallow, oxidized samples and < PM in downhole, reduced samples. Thus, high U/Pb in DREDGED MOR peridotites [1] is attributed to seafloor weathering. Given that oxidized weathering only extends tens of meters below the seafloor, we infer that most MOR peridotites have Th/Pb and U/Pb < PM. If they form with Pb isotope ratios similar to MORB, these rocks will evolve to values less radiogenic than the geochron. The effect of subduction modification on Th/Pb and U/Pb is unclear. For example, if elevated Pb is common in unaltered residual peridotites, subduction modification is likely to be minor. The size of the high Pb/Ce, low Th/Pb and U/Pb reservoir represented by these rocks depends on the reason for elevated Pb. We discuss three possibilities as outlined above. (a) Pb enrichment is most marked in highly depleted residues, abundant in the upper 30 km of the oceanic mantle. (b) Crystallization of igneous sulfide and plagioclase from cooling melt migrating along peridotite grain boundaries may be common in the upper 20 km in plates formed at slow spreading ridges. (c) Hydrothermal alteration of shallow mantle peridotite at slow spreading ridges might extend to 10 km. Based on these estimates, over geologic time tens of percent of mantle Pb could be sequestered in such a reservoir. This offers a potential solution to the "first lead paradox". [1] Niu, J. Petrol. 2004