Composition of minerals and trace elements at Mamasani thermal source: A possible preventive treatment for some skin diseases.

PubMed

Hamidizadeh, Nasrin; Simaeetabar, Shima; Handjani, Farhad; Ranjbar, Sara; Moghadam, Mohammad Gohari; Parvizi, Mohammad Mahdi

2017-01-01

Some skin diseases are incurable and modern medicine can only control them. In addition, alternative treatment remedies including balneotherapy can be effective in improving skin conditions. However, there are only a limited number of studies on particular mineral or trace elements of mineral sources that have been identified in Iran. In this respect, the amount of minerals and trace elements in Mamasani thermal source, Fars Province, Iran, was measured using electrochemical, titration, and spectrophotometric methods and evaluated. The amount of minerals and trace elements in Mamasani thermal source, Fars Province, Iran, was measured using electrochemical, titration, and spectrophotometric methods. The concentrations of natural gases such as H 2 S and NO 3 in Mamasani thermal source were measured to be 22.10 mg/L and 42.79 mg/L, respectively. The source also contained major ions such as chloride, sulfate, sodium, calcium, magnesium, potassium, and carbonate. Due to the high concentration of chloride, sulfate, and sodium ions in comparison with other major ions, the water source is also classified as sulfide water. The existing trace elements in this thermal water source are iron, zinc, copper, selenium, cobalt, chromium, boron, silisium, aluminum, magnesium, and molybdenum. We concluded that bathing in this source could be beneficial. As nitrate concentration is close to the highest standard concentration for drinking water, it can be used in chronic dermatitis, psoriasis, burns, and allergy. Furthermore, the antibacterial and antifungal effects of sulfur-containing water in this source can be helpful in the treatment of leg ulcers, tinea versicolor, tinea corporis, and tinea capitis.

X-radiography of trace fossils in limestones and dolostones from the Jurassic Smackover Formation, south Alabama

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

Esposito, R.A.; Castleman, S.P.; King, D.T. Jr.

X-radiography has been useful in studying biogenic sedimentary structures in unconsolidated sediments but the technique has not been applied often to the study of hard carbonate rock. The authors have applied x-radiography to the study of the lower part of the Smackover to enhance the complete petrologic description of the rock. The lower Smackover has many dense micrite intervals and intervals of monotonous, thin graded beds. Parts of the lower Smackover is also dolomitized. None of the above rocks contains significant amount of skeletal debris and trace fossils are not generally obvious in an etched slab of core. In limestone,more » they have detected well-preserved trace fossils by x-radiography, however. The dolostones show no traces using our method. In limestones, the traces are marked by minute amounts of finely divided iron sulfides. This causes a slight density difference resulting in greater x-ray absorption. They recognize two main trace-fossil types: a Thalassinoides best seen in slabs cut parallel to bedding and a Zoophycos best seen in slabs cut perpendicular to bedding. The technique requires a slab cut 8 mm thick with parallel flat surfaces and a medical x-ray unit using accelerating voltages of 66 kV and 10 mas. Traces are most successfully imaged on industrial-quality films.« less

Hydrogeochemical survey of groundwater for selected areas in the Arabian Shield and in cover rocks, Kingdom of Saudi Arabia

USGS Publications Warehouse

McHugh, John B.; Miller, W. Roger

1989-01-01

In the spring of 1984, a hydrogeochemical survey was conducted in the Kingdom of Saudi Arabia to test ground water as a sampling medium in exploration for mineral deposits. Eighty-one water samples (mostly from wells) were collected. The samples were analysed for the presence and concentration of major cations and anions, as well as a suite of trace elements. Most of the water samples contained high concentrations of dissolved salts. The majority of the samples showed no significant amounts of the trace elements. A few well-water samples contained moderately anomalous concentrations of zinc, molybdenum, and uranium. These anomalies could be due to salinity effects, contamination, or the proximity of mineral sources. This survey has established some baseline water-chemistry data, especially for the trace metals, which to date have not been reported in ground water in the Kingdom of Saudi Arabia.

Speciation, Characterization, And Mobility Of As, Se and Hg In Flue Gas Desulphurization Residues

EPA Science Inventory

Flue gas from coal combustion contains significant amounts of volatile toxic trace elements such as arsenic (As), selenium (Se) and mercury (Hg). The capture of these elements in the flue gas desulphurization (FGD) scrubber unit has resulted in generation of a metal-laden residue...

Reconnaissance geology of the Al Ba'ayith quadrangle, sheet 26/41 D, Kingdom of Saudi Arabia

USGS Publications Warehouse

Williams, P.L.; Simonds, F.W.; Turner, J.D.

1985-01-01

Gold-bearing quartz veins occur associated with small plutons of the Idah suite in the southeastern part of the quadrangle, and have been mined in the past. Ironstones, near Murran in the center of the quadrangle contain trace amounts of silver and gold.

POM-assisted electrochemical delignification and bleaching of chemical pulp

Treesearch

Helene Laroche; Mohini Sain; Carl Houtman; Claude Daneault

2001-01-01

A polyoxometalate-catalyzed electrochemical process has shown good selectivity in delignifying pulp. This breakthrough in redox catalysis shows promise for the development of a new environmentally benign technology for pulp bleaching. The electrochemical process, applied with a mildly alkaline electrolyte solution containing trace amounts of a vanadium-based...

Determination of trace elements in dairy milk collected from the environment of coal-fired power plant.

PubMed

Ramamurthy, N; Thillaivelavan, K

2005-01-01

In the present study the environmental effects on herbivores mammals in and around Coal-fired power plant were studied by collecting the various milk samples of Cow and Buffalo in clean polyethylene bottles. Milk samples collected at five different locations along the banks of the Paravanaru river in and around Neyveli area. These samples were prepared for trace metal determination. The concentration of trace metals (Cu, Zn, Ni, Cd, Cr, Mn, Co and Hg) were determined by Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) and Cold Vapour Atomic Absorption Spectrometry (CVAAS). It is observed that the samples contain greater amounts of trace metals than that in the unexposed areas. Obviously the milk samples are contaminated with these metals due to fly ash released in such environment.

Steam stable mesoporous silica MCM-41 stabilized by trace amounts of Al.

PubMed

Tompkins, Jordan T; Mokaya, Robert

2014-02-12

Evaluation of low and ultralow Al content (Si/Al between 50 and 412) aluminosilicate Al-MCM-41 materials synthesized via three contrasting alumination routes, namely, direct mixed-gel synthesis, post-synthesis wet grafting, and post-synthesis dry grafting, indicates that trace amounts of Al introduced via dry grafting can stabilize mesoporous silica MCM-41 to steaming at 900 °C for 4 h. It was found that trace amounts of Al (Si/Al > 400) introduced via so-called dry grafting of Al stabilize the virtually purely siliceous MCM-41 to steaming, whereas Al incorporated via other methods that involve aqueous media such as direct mixed gel synthesis or wet grafting of Al offer only limited protection at low Al content. It is particularly remarkable that a post-synthesis dry grafted Al-MCM-41 material possessing trace amounts of Al (i.e., Si/Al ratio of 412) and surface area and pore volume of 1112 m(2)/g and 1.20 cm(3)/g, respectively, retains 90% (998 m(2)/g) of the surface area and 85% (1.03 cm(3)/g) of the pore volume after exposure to steaming at 900 °C for 4 h. Under similar steam treatment conditions, the mesostructure of pure silica Si-MCM-41 is virtually destroyed and undergoes a 93% reduction in surface area (958 m(2)/g to 69 m(2)/g) and 88% decrease in pore volume (0.97 cm(3)/g to 0.12 cm(3)/g). The steam stable ultralow (i.e., trace) Al containing MCM-41 materials is found to be virtually similar to mesoporous pure silica Si-MCM-41 with hardly any detectable acidity. The improvement in steam stability arises from not only the presence of trace amounts of Al, but also from an apparent increase in the level of silica condensation that is specific to dry grafted alluminosilicate MCM-41 materials. The more highly condensed framework has fewer silanol groups and therefore is more resistant to hydrolysis under steaming conditions.

Composition of minerals and trace elements at Mamasani thermal source: A possible preventive treatment for some skin diseases

PubMed Central

Hamidizadeh, Nasrin; Simaeetabar, Shima; Handjani, Farhad; Ranjbar, Sara; Moghadam, Mohammad Gohari; Parvizi, Mohammad Mahdi

2017-01-01

INTRODUCTION: Some skin diseases are incurable and modern medicine can only control them. In addition, alternative treatment remedies including balneotherapy can be effective in improving skin conditions. However, there are only a limited number of studies on particular mineral or trace elements of mineral sources that have been identified in Iran. In this respect, the amount of minerals and trace elements in Mamasani thermal source, Fars Province, Iran, was measured using electrochemical, titration, and spectrophotometric methods and evaluated. MATERIALS AND METHODS: The amount of minerals and trace elements in Mamasani thermal source, Fars Province, Iran, was measured using electrochemical, titration, and spectrophotometric methods. RESULTS: The concentrations of natural gases such as H2S and NO3 in Mamasani thermal source were measured to be 22.10 mg/L and 42.79 mg/L, respectively. The source also contained major ions such as chloride, sulfate, sodium, calcium, magnesium, potassium, and carbonate. Due to the high concentration of chloride, sulfate, and sodium ions in comparison with other major ions, the water source is also classified as sulfide water. The existing trace elements in this thermal water source are iron, zinc, copper, selenium, cobalt, chromium, boron, silisium, aluminum, magnesium, and molybdenum. CONCLUSION: We concluded that bathing in this source could be beneficial. As nitrate concentration is close to the highest standard concentration for drinking water, it can be used in chronic dermatitis, psoriasis, burns, and allergy. Furthermore, the antibacterial and antifungal effects of sulfur-containing water in this source can be helpful in the treatment of leg ulcers, tinea versicolor, tinea corporis, and tinea capitis. PMID:29296611

Trace elements content in the selected medicinal plants traditionally used for curing skin diseases by the natives of Mizoram, India.

PubMed

Rajan, Jay Prakash; Singh, Kshetrimayum Birla; Kumar, Sanjiv; Mishra, Raj Kumar

2014-09-01

To determine the trace elements content in the selected medicinal plants, namely, Eryngium foetidum L., Mimosa pudica L., Polygonum plebeium, and Prunus cerasoides D. Don traditionally used by the natives of the Mizoram, one of the north eastern states in India as their folklore medicines for curing skin diseases like eczema, leg and fingers infection, swelling and wound. A 3 MeV proton beam of proton induced X-ray emission technique, one of the most powerful techniques for its quick multi elemental trace analysis capability and high sensitivity was used to detect and characterized for trace elements. The studies revealed that six trace elements, namely, Fe, Zn, Cu, Mn, V, and Co detected in mg/L unit were present in varying concentrations in the selected medicinal plants with high and notable concentration of Fe, Zn, Mn and appreciable amount of the Cu, Co and V in all the plants. The results of the present study support the therapeutic usage of these medicinal plants in the traditional practices for curing skin diseases since they are found to contain appreciable amount of the Fe, Zn, Cu, Mn, V and Co. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

Procedures of determining organic trace compounds in municipal sewage sludge-a review.

PubMed

Lindholm-Lehto, Petra C; Ahkola, Heidi S J; Knuutinen, Juha S

2017-02-01

Sewage sludge is the largest by-product generated during the wastewater treatment process. Since large amounts of sludge are being produced, different ways of disposal have been introduced. One tempting option is to use it as fertilizer in agricultural fields due to its high contents of inorganic nutrients. This, however, can be limited by the amount of trace contaminants in the sewage sludge, containing a variety of microbiological pollutants and pathogens but also inorganic and organic contaminants. The bioavailability and the effects of trace contaminants on the microorganisms of soil are still largely unknown as well as their mixture effects. Therefore, there is a need to analyze the sludge to test its suitability before further use. In this article, a variety of sampling, pretreatment, extraction, and analysis methods have been reviewed. Additionally, different organic trace compounds often found in the sewage sludge and their methods of analysis have been compiled. In addition to traditional Soxhlet extraction, the most common extraction methods of organic contaminants in sludge include ultrasonic extraction (USE), supercritical fluid extraction (SFE), microwave-assisted extraction (MAE), and pressurized liquid extraction (PLE) followed by instrumental analysis based on gas or liquid chromatography and mass spectrometry.

Dietary selenium supplementation and whole blood gene expression in healthy North American men

USDA-ARS?s Scientific Manuscript database

Selenium (Se) is a trace nutrient required in microgram amounts by all animals, with a recommended dietary allowance of 55 µg/d in humans. The biological functions of Se are performed by a group of 25 selenoproteins containing the unusual amino acid selenocysteine at their active sites. The selenopr...

Hydrolysis of soybean protein improves iron bioavailability

USDA-ARS?s Scientific Manuscript database

Iron is an important trace metal element in human body. Iron deficiency affects human health, especially pregnant women and children. Soybean protein is a popular food in Asia and can contain a high amount of iron (145.70±0.74 ug/g); however, it is usually reported as an inhibitor of iron absorption...

PROCESS FOR TREATING VOLATILE METAL FLUORIDES

DOEpatents

Rudge, A.J.; Lowe, A.J.

1957-10-01

This patent relates to the purification of uranium hexafluoride, made by reacting the metal or its tetrafluoride with fluorine, from the frequently contained traces of hydrofluoric acid. According to the present process, UF/sub 6/ containing as an impurity a small amount of hydrofluoric acid, is treated to remove such impurity by contact with an anhydrous alkali metal fluoride such as sodium fluoride. In this way a non-volatile complex containing hydrofluoric acid and the alkali metal fluoride is formed, and the volatile UF /sub 6/ may then be removed by distillation.

[Determination of trace amounts of zinc in nickel electrolyte by flow injection on-line enrichment].

PubMed

Zhou, Z; Wang, Y; Dong, Z; Tong, K; Guo, X; Guo, X

1999-10-01

A method for the determination of trace amount of zinc in nickel electrolyte utilizing the flow injection on-line enrichment technique is reported in this paper. Atomic absorption spectrometer was used as detector. Zinc was separated from large amounts of nickel andother components in the electrolyte by absorption its chlorocomplex on a mini-column packed with strongly basic anion exchangers. It was found that sodium chloride containing in the electrolyte offered a sufficient chloride concentration needed for the formation of the zinc chlorocomplex and thus no additional reagent was required for the determination. The throughput of the method is 30 determinations per hour. The detection limit of the method is 0.002 microg x mL(-1) and the precision is 1.9% (RSD). The proposed method is rapid and cost-effective. It has been used for almost three years in the quality control of the electrolyte in the factory with great success.

Vitamin and trace element supplementation in grazing dairy ewe during the dry season: effect on milk yield, composition, and clotting aptitude.

PubMed

Tufarelli, Vincenzo; Petrera, F; Khan, R U; Laudadio, Vito

2011-06-01

A study was carried out to evaluate the influence of vitamin and trace mineral supplementation on milk production and composition in grazing dairy ewes during the dry season. Ewes (n = 50) were assigned at weaning to blocks and treatments. Ewes were daily conducted (8 h/day) on a pasture based on Italian ryegrass (Lolium multiflorum). At fold, ewes received a basal diet composed by ad libitum oat hay and a definite amount of a pelleted concentrate. Dietary treatments included: (1) the control concentrate containing background of vitamin and trace mineral only, and (2) the experimental concentrate containing the premix supplement (10 g/kg of dry matter). Vitamin and trace mineral supplementation did not affect ewes' body weight. Milk, fat- and protein-corrected milk, fat percentage, and clotting properties were improved in ewes fed supplemented concentrate. There was a week × treatment interaction (P < 0.05) for yield of milk and corrected milk that was greatest at peak production in ewes fed the premix. Our findings indicate that in grazing dairy ewe, the dietary vitamin and trace mineral supplementation during dry season led to an increase of milk production and quality, with positive improvement in milk clotting aptitude.

Trace elements in hazardous mineral fibres.

PubMed

Bloise, Andrea; Barca, Donatella; Gualtieri, Alessandro Francesco; Pollastri, Simone; Belluso, Elena

2016-09-01

Both occupational and environmental exposure to asbestos-mineral fibres can be associated with lung diseases. The pathogenic effects are related to the dimension, biopersistence and chemical composition of the fibres. In addition to the major mineral elements, mineral fibres contain trace elements and their content may play a role in fibre toxicity. To shed light on the role of trace elements in asbestos carcinogenesis, knowledge on their concentration in asbestos-mineral fibres is mandatory. It is possible that trace elements play a synergetic factor in the pathogenesis of diseases caused by the inhalation of mineral fibres. In this paper, the concentration levels of trace elements from three chrysotile samples, four amphibole asbestos samples (UICC amosite, UICC anthophyllite, UICC crocidolite and tremolite) and fibrous erionite from Jersey, Nevada (USA) were determined using inductively coupled plasma mass spectrometry (ICP-MS). For all samples, the following trace elements were measured: Li, Be, Sc, V, Cr, Mn, Co, Ni, Cu, Zn, As, Rb, Sr, Y, Sb, Cs, Ba, La, Pb, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Th, U. Their distribution in the various mineral species is thoroughly discussed. The obtained results indicate that the amount of trace metals such as Mn, Cr, Co, Ni, Cu and Zn is higher in anthophyllite and chrysotile samples, whereas the amount of rare earth elements (REE) is higher in erionite and tremolite samples. The results of this work can be useful to the pathologists and biochemists who use asbestos minerals and fibrous erionite in-vitro studies as positive cyto- and geno-toxic standard references. Copyright © 2016 Elsevier Ltd. All rights reserved.

Nutrient supplementation as adjunct therapy in pulmonary tuberculosis.

PubMed

Chandra, Ranjit Kumar

2004-03-01

The study examined the effect of supplementation with multivitamins and trace elements on microbiological and radiological recovery in patients with pulmonary tuberculosis. Forty-four patients aged 28-50 years were diagnosed with active pulmonary tuberculosis based on X-ray of the chest and smear examination of the sputum for the presence of acid-fast bacilli. They were all treated for six months with a standard anti-tuberculosis regimen that has been found to be effective worldwide for disease control. The subjects were randomized to receive either a multivitamin-trace element supplement or a placebo containing calcium. The two groups were matched on all relevant confounding variables. At two months into the treatment, the group that was supplemented with a multivitamin-trace element preparation showed a significant reduction in the number of individuals with sputum smear positive for acid-fast bacillus: two out of 22 individuals, compared with seven out of 22 among placebo-treated controls (p = 0.028, Fisher's test). It is concluded that patients with tuberculosis should be supplemented with a suitable micronutrient preparation that contains optimum amounts of all vitamins and trace elements that have been documented to enhance the immune response.

Chemical quality of ground water in San Joaquin and part of Contra Costa Counties, California

USGS Publications Warehouse

Sorenson, Stephen K.

1981-01-01

Chemical water-quality conditions were investigated in San Joaquin and part of Contra Costa Counties by canvassing available wells and sampling water from 324 representative wells. Chemical water types varied, with 73 percent of the wells sampled containing either calcium-magnesium bicarbonate, or calcium-sodium bicarbonate type water. Substantial areas contain ground water exceeding water-quality standards for boron, manganese, and nitrate. Trace elements, with the exception of boron and manganese, were present in negligible amounts. (USGS)

Corrosion of Pipeline and Wellbore Steel by Liquid CO2 Containing Trace Amounts of Water and SO2

NASA Astrophysics Data System (ADS)

McGrail, P.; Schaef, H. T.; Owen, A. T.

2009-12-01

Carbon dioxide capture and storage in deep saline formations is currently considered the most attractive option to reduce greenhouse gas emissions with continued use of fossil fuels for energy production. Transporting captured CO2 and injection into suitable formations for storage will necessarily involve pipeline systems and wellbores constructed of carbon steels. Industry standards currently require nearly complete dehydration of liquid CO2 to reduce corrosion in the pipeline transport system. However, it may be possible to establish a corrosion threshold based on H2O content in the CO2 that could allow for minor amounts of H2O to remain in the liquid CO2 and thereby eliminate a costly dehydration step. Similarly, trace amounts of sulfur and nitrogen compounds common in flue gas streams are currently removed through expensive desulfurization and catalytic reduction processes. Provided these contaminants could be safely and permanently transported and stored in the geologic reservoir, retrofits of existing fossil-fuel plants could address comprehensive emissions reductions, including CO2 at perhaps nearly the same capital and operating cost. Because CO2-SO2 mixtures have never been commercially transported or injected, both experimental and theoretical work is needed to understand corrosion mechanisms of various steels in these gas mixtures containing varying amounts of water. Experiments were conducted with common tool steel (AISI-01) and pipeline steel (X65) immersed in liquid CO2 at room temperature containing ~1% SO2 and varying amounts of H2O (0 to 2500 ppmw). A threshold concentration of H2O in the liquid CO2-SO2 mixture was established based on the absence of visible surface corrosion. For example, experiments exposing steel to liquid CO2-SO2 containing ~300 ppmw H2O showed a delay in onset of visible corrosion products and minimal surface corrosion was visible after five days of testing. However increasing the water content to 760 ppmw produced extensive surface corrosion after 48 hours at room temperature. Surface characterization by SEM showed one type of morphology that included large circular features radiating outward from a central structure. Chemical analyses obtained by SEM-EDX indicate the phases contained mostly Fe and S with minor amounts of Mn. Corrosion products completely covering the metal coupon surface were identified by XRD as iron sulfite hydrate (FeSO3●3H2O), with lesser amounts of gravegliaite (MnSO3●3H2O), and rozenite (Fe(SO4)●(H2O)4).

Blood-collection device for trace and ultra-trace metal specimens evaluated.

PubMed

Moyer, T P; Mussmann, G V; Nixon, D E

1991-05-01

We evaluated the evacuated phlebotomy tube designed specifically for trace metal analysis by Sherwood Medical Co. Pools of human serum containing known concentrations of aluminum, arsenic, calcium, cadmium, copper, chromium, iron, lead, magnesium, manganese, mercury, selenium, and zinc were exposed to the tube and rubber stopper for defined periods ranging from 5 min to 24 h. Analysis for each element was performed in a randomized fashion under rigidly controlled conditions by use of standard electrothermal atomization atomic absorption spectroscopy, inductively coupled plasma atomic emission spectroscopy, and cold vapor atomic absorption spectrometry. In addition, for comparative purposes, we collected blood samples from normal volunteers by use of ultra-clean polystyrene phlebotomy syringes as well as standard evacuated phlebotomy tubes. We conclude that, except for lead, there was no significant contribution of any trace element studied from the evaluated tube and stopper to the serum. Because whole blood is the usual specimen for lead testing, the observation of a trace amount of lead in this tube designed for serum collection is trivial.

Method for Trace Oxygen Detection

NASA Technical Reports Server (NTRS)

Man, Kim Fung (Inventor); Boumsellek, Said (Inventor); Chutjian, Ara (Inventor)

1997-01-01

Trace levels of molecular oxygen are measured by introducing a gas containing the molecular oxygen into a target zone, and impacting the molecular oxygen in the target zone with electrons at the O(-) resonant energy level for dissociative electron attachment to produce O(-) ions. Preferably, the electrons have an energy of about 4 to about 10 eV. The amount of O(-) ions produced is measured, and is correlated with the molecular oxygen content in the target zone. The technique is effective for measuring levels of oxygen below 50 ppb. and even less than 1 ppb. The amount of O(-) can be measured in a quadrupole mass analyzer. Best results are obtained when the electrons have an energy of about 6 to about 8 eV. and preferably about 6.8 eV. The method can be used for other species by selecting the appropriate electron energy level.

Parallel program debugging with flowback analysis

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

Choi, Jongdeok.

1989-01-01

This thesis describes the design and implementation of an integrated debugging system for parallel programs running on shared memory multi-processors. The goal of the debugging system is to present to the programmer a graphical view of the dynamic program dependences while keeping the execution-time overhead low. The author first describes the use of flowback analysis to provide information on causal relationship between events in a programs' execution without re-executing the program for debugging. Execution time overhead is kept low by recording only a small amount of trace during a program's execution. He uses semantic analysis and a technique called incrementalmore » tracing to keep the time and space overhead low. As part of the semantic analysis, he uses a static program dependence graph structure that reduces the amount of work done at compile time and takes advantage of the dynamic information produced during execution time. The cornerstone of the incremental tracing concept is to generate a coarse trace during execution and fill incrementally, during the interactive portion of the debugging session, the gap between the information gathered in the coarse trace and the information needed to do the flowback analysis using the coarse trace. Then, he describes how to extend the flowback analysis to parallel programs. The flowback analysis can span process boundaries; i.e., the most recent modification to a shared variable might be traced to a different process than the one that contains the current reference. The static and dynamic program dependence graphs of the individual processes are tied together with synchronization and data dependence information to form complete graphs that represent the entire program.« less

Problems of Determining the Content of Cr(VI) in Raw Materials and Materials Containing Chromite Ore.

PubMed

Stec, Katarzyna

2017-11-02

Materials made with chromite ore are widely applied in the industry metallurgy as well as in the foundry industry. The oxidation number of chromium in these materials is both (III) and (VI). Currently there are no procedures allowing proper determination of chrome in chromite ores and ore-containing materials. The analytical methods applied, which are dedicated to a very narrow range of materials, e.g., cement, and cannot be applied in the case of materials which, apart from trace amounts of Cr(VI), contain mainly compounds of Cr(III), Fe(III) as well as trace compounds of Cu(II), Ni(II) and V(V). In the work particular attention has been paid to the preparation of test samples and creating measurement conditions in which interferences from Cr(III) and Fe(III) spectral lines could be minimized. Two separate instrumental measurement techniques have been applied: Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP AES) and the spectrophotometric method using diphenylcarbazide.

Changes in Trace Gas Nitrogen Emissions as a Response to Ecosystem Type Conversion in a Semi-Arid Climate.

NASA Astrophysics Data System (ADS)

Andrews, H.; Eberwein, J. R.; Jenerette, D.

2016-12-01

As humans continue to introduce exotic plants and to alter climate and fire regimes in semi-arid ecosystems, many plant communities have begun to shift from perennial forbs and shrubs to annual grasses with different functional traits. Shifts in plant types are also associated with shifts in microclimate, microbial activity, and litter inputs, all of which contribute to the efficiency of nitrogen processing and the magnitude of trace gas emissions (NOx and N2O), which are increasingly important fluxes in water-limited systems. Here, we explored how changes in plant litter impact trace gas emissions, asking the question: How does conversion from a native shrubland to exotic grassland ecosystem alter NOx and N2O fluxes in a semi-arid climate? We posed two hypotheses to explain the impacts of different types of litter on soils disturbed by exotic grasses and those that were still considered shrublands: 1.) Soils that have undergone conversion by exotic grasses release higher amounts of NOx and N2O than do those of unconverted shrublands, due to disruptions of native plant and soil processes by exotic grasses, and 2.) Because litter of exotic grasses has lower C:N than that of shrubs, litter inputs from exotic grasses will increase NOx and N2O emissions from soils more than will litter inputs from shrubs. As a preliminary study, we experimentally wetted mesocosms in a laboratory incubation containing converted and unconverted soils that had been mixed with no litter or either exotic grass or coastal sage scrub (CSS) litter. We measured N2O fluxes from mesocosms over a 48-hour period. 24 hours after wetting, samples with grass litter produced higher amounts of N2O than those with CSS litter; similarly, converted soils produced higher amounts of N2O than unconverted soils. These two effects combined resulted in exotic grassland conditions (converted soils with exotic grass litter) producing 10 times the amount of N2O as those containing native shrubland conditions (unconverted soils with CSS litter). Additionally, soils with no litter peaked in N2O emissions earlier than those with litter (12 hours after wetting compared to 24 hours after wetting). Following preliminary results, we suggest that differences in plant traits, such as litter, play a significant role in the magnitude and timing of trace gas nitrogen emissions.

Aerogel volatiles concentrator and analyzer (AVCA) - Collection and concentration of trace volatile organics in aerogel for spectroscopic detection

NASA Astrophysics Data System (ADS)

Tsapin, A.; Jones, S.; Petkov, M.; Borchardt, D.; Anderson, M.

2017-03-01

A study was conducted to determine the efficacy of using silica aerogel to collect and concentrate ambient trace organics for spectroscopic analysis. Silica aerogel was exposed to atmospheres containing trace amounts of polycyclic aromatic and aliphatic hydrocarbons. The organics present were concentrated in the aerogels by factors varying from 10 to more than 1000 over the levels found in the atmospheres, depending on the specific organic present. Since silica aerogel is transparent over a wide range of optical and near infrared wavelengths, UV-induced fluorescence, Raman and infrared spectroscopies were used to detect and identify the organics collected by the aerogel. Measurements were conducted to determine the sensitivity of these spectroscopic methods for determining organics concentrated by aerogels and the effectiveness of this method for identifying systems containing multiple organic species. Polycyclic aromatic hydrocarbons (PAHs) were added to simulated Mars regolith and then vaporized by modest heating in the presence of aerogel. The aerogels adsorbed and concentrated the PAHs, which were detected by induced fluorescence and Raman and FTIR spectroscopies.

Vitamin A and carotene contents of some wildlife foods

USGS Publications Warehouse

Nestler, R.B.; Derby, J.V.; DeWitt, J.B.

1949-01-01

In order to determine possible sources of vitamin A for quail, 37 species of insects and other invertebrates were analyzed for vitamin A and for carotene, and 26 species of seeds and fruits were assayed for carotene. The invertebrates showed no trace of vitamin A; but 8 herbivorous invertebrates and the praying mantis contained carotene. Most of the plants contained carotene--some of them a lot (dotted smartweed, some legumes, sumac, roses, bittersweet, etc.). The amount of carotene varied among plants of the same species and even among fruits on the same plant.

Food of the American smelt in Saginaw Bay, Lake Huron

USGS Publications Warehouse

Gordon, William G.

1961-01-01

In order to determine possible sources of vitamin A for quail, 37 species of insects and other invertebrates were analyzed for vitamin A and for carotene, and 26 species of seeds and fruits were assayed for carotene. The invertebrates showed no trace of vitamin A; but 8 herbivorous invertebrates and the praying mantis contained carotene. Most of the plants contained carotene--some of them a lot (dotted smartweed, some legumes, sumac, roses, bittersweet, etc.). The amount of carotene varied among plants of the same species and even among fruits on the same plant.

Integrated capture of fossil fuel gas pollutants including CO.sub.2 with energy recovery

DOEpatents

Ochs, Thomas L [Albany, OR; Summers, Cathy A [Albany, OR; Gerdemann, Steve [Albany, OR; Oryshchyn, Danylo B [Philomath, OR; Turner, Paul [Independence, OR; Patrick, Brian R [Chicago, IL

2011-10-18

A method of reducing pollutants exhausted into the atmosphere from the combustion of fossil fuels. The disclosed process removes nitrogen from air for combustion, separates the solid combustion products from the gases and vapors and can capture the entire vapor/gas stream for sequestration leaving near-zero emissions. The invention produces up to three captured material streams. The first stream is contaminant-laden water containing SO.sub.x, residual NO.sub.x particulates and particulate-bound Hg and other trace contaminants. The second stream can be a low-volume flue gas stream containing N.sub.2 and O.sub.2 if CO2 purification is needed. The final product stream is a mixture comprising predominantly CO.sub.2 with smaller amounts of H.sub.2O, Ar, N.sub.2, O.sub.2, SO.sub.X, NO.sub.X, Hg, and other trace gases.

Separation of metal ions from aqueous solutions

DOEpatents

Almon, Amy C.

1994-01-01

A process and apparatus for quantitatively and selectively separating metal ions from mixtures thereof in aqueous solution. The apparatus includes, in combination, a horizontal electrochemical flow cell containing flow bulk electrolyte solution and an aqueous, metal ion-containing solution, the cell containing a metal mesh working electrode, a counter electrode positioned downstream from the working electrode, an independent variable power supply/potentiostat positioned outside of the flow cell and connected to the electrodes, and optionally a detector such as a chromatographic detector, positioned outside the flow cell. This apparatus and its operation has significant application where trace amounts of metal ions are to be separated.

Effects of reaction conditions on the emission behaviors of arsenic, cadmium and lead during sewage sludge pyrolysis.

PubMed

Han, Hengda; Hu, Song; Syed-Hassan, Syed Shatir A; Xiao, Yiming; Wang, Yi; Xu, Jun; Jiang, Long; Su, Sheng; Xiang, Jun

2017-07-01

Sewage sludge is an important class of bioresources whose energy content could be exploited using pyrolysis technology. However, some harmful trace elements in sewage sludge can escape easily to the gas phase during pyrolysis, increasing the potential of carcinogenic material emissions to the atmosphere. This study investigates emission characteristics of arsenic, cadmium and lead under different pyrolysis conditions for three different sewage sludge samples. The increased temperature (within 723-1123K) significantly promoted the cadmium and lead emissions, but its influence on arsenic emission was not pronounced. The releasing rate order of the three trace elements is volatile arsenic compounds>cadmium>lead in the beginning of pyrolysis. Fast heating rates promoted the emission of trace elements for the sludge containing the highest amount of ash, but exhibited an opposite effect for other studied samples. Overall, the high ash sludge released the least trace elements almost under all reaction conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Elemental Geochemistry of Samples From Fault Segments of the San Andreas Fault Observatory at Depth (SAFOD) Drill Hole

NASA Astrophysics Data System (ADS)

Tourscher, S. N.; Schleicher, A. M.; van der Pluijm, B. A.; Warr, L. N.

2006-12-01

Elemental geochemistry of mudrock samples from phase 2 drilling of the San Andreas Fault Observatory at Depth (SAFOD) is presented from bore hole depths of 3066 m to 3169 m and from 3292 m to 3368 m, which contain a creeping section and main trace of the fault, respectively. In addition to preparation and analysis of whole rock sample, fault grains with neomineralized, polished surfaces were hand picked from well-washed whole rock samples, minimizing the potential contamination from drilling mud and steel shavings. The separated fractions were washed in deionized water, powdered using a mortar and pestle, and analyzed using an Inductively Coupled Plasma- Optical Emission Spectrometer for major and minor elements. Based on oxide data results, systematic differences in element concentrations are observed between the whole rock and fault rock. Two groupings of data points are distinguishable in the regions containing the main trace of the fault, a shallow part (3292- 3316 m) and a deeper section (3320-3368 m). Applying the isocon method, assuming Zr and Ti to be immobile elements in these samples, indicates a volume loss of more than 30 percent in the shallow part and about 23 percent in the deep part of the main trace. These changes are minimum estimates of fault-related volume loss, because the whole rock from drilling samples contains variable amount of fault rock as well. Minimum estimates for volume loss in the creeping section of the fault are more than 50 percent when using the isocon method, comparing whole rock to plucked fault rock. The majority of the volume loss in the fault rocks is due to the dissolution and loss of silica, potassium, aluminum, sodium and calcium, whereas (based on oxide data) the mineralized surfaces of fractures appear to be enriched in Fe and Mg. The large amount of element mobility within these fault traces suggests extensive circulation of hydrous fluids along fractures that was responsible for progressive dissolution and leaching of the wall rock during faulting.

The effect of broad-spectrum antibiotics on warfarin excretion and metabolism in the rat

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

Remmel, R.P.; Elmer, G.W.

The excretion and metabolism of /sup 14/C-warfarin in rats was examined in a crossover experiment, the first phase consisting of treatment with normal saline, the second phase using the same animals given neomycin, bacitracin, and tetracycline orally. Urine and feces were collected every 24 hours for 72 hours and examined for warfarin and its metabolites, both unconjugated and conjugated. Significantly more radioactivity was eliminated in th feces of antibiotic-treated rats. The feces of antibiotic-treated rats contained only trace amounts of beta-glucuronidase activity. Urine contained a similar ratio of unconjugated to conjugated radioactivity in both treatment groups, but the antibiotic-treated animalsmore » had significantly larger amount of conjugates in their feces. Examination of metabolic profiles of conjugated and unconjugated fractions revealed significantly fewer hydroxylated metabolites in antibiotic-treated rats, especially in the feces. The lower amount of hydroxylative metabolism in attributed to a reduction in gut flora-medicated interohepatic recycling caused by the antibiotics.« less

Differential auger spectrometry

DOEpatents

Strongin, Myron; Varma, Matesh Narayan; Anne, Joshi

1976-06-22

Differential Auger spectroscopy method for increasing the sensitivity of micro-Auger spectroanalysis of the surfaces of dilute alloys, by alternately periodically switching an electron beam back and forth between an impurity free reference sample and a test sample containing a trace impurity. The Auger electrons from the samples produce representative Auger spectrum signals which cancel to produce an Auger test sample signal corresponding to the amount of the impurity in the test samples.

Cubane Derivatives for Propellant Applicationsxb

DTIC Science & Technology

1989-07-03

cycloperitanone ketal containing 2-3% cyclopentanone and trace amounts of toluene. Approximately 4 liters of purified cyclopentanone ketal per day could be...such as reaction with trimethyl phosphite , also gave inconsistent results. In reactions involving 45 moles of ketal in a 20 gallon Pfaudler reactor...Dioxane treated with trimethyl phosphite Dehydrohalogenation and Dimerization of the Tribromo Ketal to the Bisketal. In-0 0 stop 3 0 Gr r or [to"t

Preparation of Some Homologous TEMPO Nitroxides and Oxoammonium Salts; Notes on the NMR Spectroscopy of Nitroxide Free Radicals; Observed Radical Nature of Oxoammonium Salt Solutions Containing Trace Amounts of Corresponding Nitroxides in an Equilibrium Relationship.

PubMed

Bobbitt, James M; Eddy, Nicholas A; Cady, Clyde X; Jin, Jing; Gascon, Jose A; Gelpí-Dominguez, Svetlana; Zakrzewski, Jerzy; Morton, Martha D

2017-09-15

Three new homologous TEMPO oxoammonium salts and three homologous nitroxide radicals have been prepared and characterized. The oxidation properties of the salts have been explored. The direct 13 C NMR and EPR spectra of the nitroxide free radicals and the oxoammonium salts, along with TEMPO and its oxoammonium salt, have been successfully measured with little peak broadening of the NMR signals. In the spectra of all ten compounds (nitroxides and corresponding oxoammonium salts), the carbons in the 2,2,6,6-tetramethylpiperidine core do not appear, implying paramagnetic properties. This unpredicted overall paramagnetism in the oxoammonium salt solutions is explained by a redox equilibrium as shown between oxoammonium salts and trace amounts of corresponding nitroxide. This equilibrium is confirmed by electron interchange reactions between nitroxides with an N-acetyl substituent and oxoammonium salts with longer acyl side chains.

Electron-rich triphenylamine-based sensors for picric acid detection.

PubMed

Chowdhury, Aniket; Mukherjee, Partha Sarathi

2015-04-17

This paper demonstrates the role of solvent in selectivity and sensitivity of a series of electron-rich compounds for the detection of trace amounts of picric acid. Two new electron-rich fluorescent esters (6, 7) containing a triphenylamine backbone as well as their analogous carboxylic acids (8, 9) have been synthesized and characterized. Fluorescent triphenylamine coupled with an ethynyl moiety constitutes π-electron-rich selective and sensitive probes for electron-deficient picric acid (PA). In solution, the high sensitivity of all the sensors toward PA can be attributed to a combined effect of the ground-state charge-transfer complex formation and resonance energy transfer between the sensor and analyte. The acids 8 and 9 also showed enhanced sensitivity for nitroaromatics in the solid state, and their enhanced sensitivity could be attributed to exciton migration due to close proximity of the neighboring acid molecules, as evident from the X-ray diffraction study. The compounds were found to be quite sensitive for the detection of trace amount of nitroaromatics in solution, solid, and contact mode.

Ambient methods and apparatus for rapid laser trace constituent analysis

DOEpatents

Snyder, Stuart C.; Partin, Judy K.; Grandy, Jon D.; Jeffery, Charles L.

2002-01-01

A method and apparatus are disclosed for measuring trace amounts of constituents in samples by using laser induced breakdown spectroscopy and laser induced fluorescence under ambient conditions. The laser induced fluorescence is performed at a selected wavelength corresponding to an absorption state of a selected trace constituent. The intensity value of the emission decay signal which is generated by the trace constituent is compared to calibrated emission intensity decay values to determine the amount of trace constituent present.

Organochlorine-induced mortality and residues in long-billed curlews from Oregon

USGS Publications Warehouse

Blus, L.J.; Henny, Charles J.; Krynitsky, A.J.

1985-01-01

In order to determine possible sources of vitamin A for quail, 37 species of insects and other invertebrates were analyzed for vitamin A and for carotene, and 26 species of seeds and fruits were assayed for carotene. The invertebrates showed no trace of vitamin A; but 8 herbivorous invertebrates and the praying mantis contained carotene. Most of the plants contained carotene--some of them a lot (dotted smartweed, some legumes, sumac, roses, bittersweet, etc.). The amount of carotene varied among plants of the same species and even among fruits on the same plant.

N-nitrosodimethylamine, nitrate and nitrate-reducing microorganisms in human milk.

PubMed

Uibu, J; Tauts, O; Levin, A; Shimanovskaya, N; Matto, R

1996-10-01

Of 54 milk samples from 54 healthy nursing women analysed for volatile N-nitrosamines, 42 appeared negative. Trace amounts (below the detection limit 0.5 microgram l-1) of N-nitrosodimethylamine were detected in the milk of 10 mothers and two samples contained this compound at 1.1 and 1.2 micrograms 1-1 respectively. Almost all samples investigated contained nitrate (mean 2.9 +/- 2.3 mg1-1 and nitrate reducing microorganisms (mean 4.2 +/- 1.0 log ml-1). The recent finding of N-nitrosodimethylamine in human milk gives evidence of the continuous endogenous formation of N-nitrosamines.

[Trace analysis of aristolochic acid A].

PubMed

Liu, Yalin; Gao, Huimin; Wang, Zhimin; Zhang, Qiwei

2010-12-01

A HPLC method for limit detection of aristolochic acid A in the Chinese herbs containing aristolochic acid or suspected-containing aristolochic acid and their preparations was established. The samples were analyzed on an Alltima C18 column eluted with methanol-water-acetic acid (68:32:1.5) as the mobile phase. Flow rate was at 1.0 mL x min(-1) and the detection wavelength was at 390 nm. The calibration curve was linear over the range from 0.016 to 0.51 g (r = 0.9993) and LOD was 4 ng. The average recovery was 101.2% with RSD of 2.01%. The procedures of sample preparation were systematically investigated. The contents of aristolochic acid A in Radix et Rhizoma Asari bought from market or drugstore were fluctuated from 3.1 to 26.6 microg x g(-1) and 3 of 11 samples accorded with the quality requirement of current Chinese Pharmacopoeia. Among 15 batches samples of Chinese medicaments, only one sample was found to contain aristolochic acid A. The present investigation shows that the method is sensitive and repeatable and it could be used for the limit detection of aristolochic acid A in the Chinese herbal medicines containing trace amount of aristolochic acid A or suspected-containing aristolochic acid A and their preparations.

Trace detection of perchlorate in industrial-grade emulsion explosive with portable surface-enhanced Raman spectroscopy.

PubMed

Nuntawong, N; Eiamchai, P; Limwichean, S; Wong-ek, B; Horprathum, M; Patthanasettakul, V; Leelapojanaporn, A; Nakngoenthong, S; Chindaudom, P

2013-12-10

Recent analyses by ion-exchange chromatography (IC) showed that, beside nitrate, the majority of the industrial-grade emulsion explosives, extensively used by most separatists in the southern Thailand insurgency, contained small traces of perchlorate anions. In demand for the faster, reliable, and simple detection methods, the portable detection of nitrate and perchlorate became the great interest for the forensic and field-investigators. This work proposed a unique method to detect the trace amount of perchlorate in seven industrial-grade emulsion explosives under the field tests. We utilized the combination of the portable Raman spectroscope, the developed surfaced-enhanced Raman substrates, and the sample preparation procedures. The portable Raman spectroscope with a laser diode of 785 nm for excitation and a thermoelectric-cooled CCD spectrometer for detection was commercially available. The SERS substrates, with uniformly distributed nanostructured silver nanorods, were fabricated by the DC magnetron sputtering system, based on the oblique-angle deposition technique. The sample preparation procedures were proposed based on (1) pentane extraction technique and (2) combustion technique, prior to being dissolved in the purified water. In comparison to the ion chromatography and the conventional Raman measurements, our proposed methods successfully demonstrated the highly sensitive detectability of the minimal trace amount of perchlorate from five of the explosives with minimal operating time. This work was therefore highly practical to the development for the forensic analyses of the post-blast explosive residues under the field-investigations. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Quantification of fluorine traces in solid samples using CaF molecular emission bands in atmospheric air Laser-Induced Breakdown Spectroscopy

NASA Astrophysics Data System (ADS)

Alvarez-Llamas, C.; Pisonero, J.; Bordel, N.

2016-09-01

Direct solid determination of trace amounts of fluorine using Laser-Induced Breakdown Spectroscopy (LIBS) is a challenging task due to the low excitation efficiency of this element. Several strategies have been developed to improve the detection capabilities, including the use of LIBS in a He atmosphere to enhance the signal to background ratios of F atomic emission lines. An alternative method is based on the detection of the molecular compounds that are formed with fluorine in the LIBS plasma. In this work, the detection of CaF molecular emission bands is investigated to improve the analytical capabilities of atmospheric air LIBS for the determination of fluorine traces in solid samples. In particular, Cu matrix samples containing different fluorine concentration (between 50 and 600 μg/g), and variable amounts of Ca, are used to demonstrate the linear relationships between CaF emission signal and F concentration. Limits of detection for fluorine are improved by more than 1 order of magnitude using CaF emission bands versus F atomic lines, in atmospheric-air LIBS. Furthermore, a toothpaste powder sample is used to validate this analytical method. Good agreement is observed between the nominal and the predicted fluorine mass-content.

Trace Amounts of Furan-2-Carboxylic Acids Determine the Quality of Solid Agar Plates for Bacterial Culture

PubMed Central

Hara, Shintaro; Isoda, Reika; Tahvanainen, Teemu; Hashidoko, Yasuyuki

2012-01-01

Background Many investigators have recognised that a significant proportion of environmental bacteria exist in a viable but non-culturable state on agar plates, and some researchers have also noticed that some of such bacteria clearly recover their growth on matrices other than agar. However, the reason why agar is unsuitable for the growth of some bacteria has not been addressed. Methodology/Principal Findings According to the guide of a bioassay for swarming inhibition, we identified 5-hydroxymethylfuran-2-carboxylic acid (5-HMFA) and furan-2-carboxylic acid (FA) as factors that inhibit bacterial swarming and likely inhibit extracellular polysaccharide production on agar. The furan-2-carboxylic acids 5-HMFA and FA effectively inhibited the swarming and swimming of several environmental bacteria at concentrations of 1.8 and 2.3 µg L−1 (13 and 21 nmol L−1), respectively, which are equivalent to the concentrations of these compounds in 0.3% agar. On Luria-Bertani (LB) plates containing 1.0% agar that had been previously washed with MeOH, a mixture of 5-HMFA and FA in amounts equivalent to their original concentrations in the unwashed agar repressed the swarming of Escherichia coli K12 strain W3110, a representative swarming bacterium. Conclusions/Significance Agar that contains trace amounts of 5-HMFA and FA inhibits the proliferation of some slow-growing or difficult-to-culture bacteria on the plates, but it is useful for single colony isolation due to the ease of identification of swarmable bacteria as the non-swarmed colonies. PMID:22848437

Direct write of copper-graphene composite using micro-cold spray

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

Dardona, Sameh, E-mail: dardona@utrc.utc.com; She, Ying; Schmidt, Wayde R.

Direct write of a new class of composite materials containing copper and graphene in the powder phase is described. The composite was synthesized using batch electroless plating of copper for various times onto Nano Graphene Platelets (NGP) to control the amount of copper deposited within the loosely aggregated graphene powder. Copper deposition was confirmed by both Focused Ion Beam (FIB) and Auger electron spectroscopic analysis. A micro-cold spray technique was used to deposit traces that are ∼230 μm wide and ∼5 μm thick of the formulated copper/graphene powder onto a glass substrate. The deposited traces were found to have goodmore » adhesion to the substrate with ∼65x the copper bulk resistivity.« less

Neutralization of Hydroxide Ion in Melt-Grown NaCl Crystals

NASA Technical Reports Server (NTRS)

Otterson, Dumas A.

1961-01-01

Many recent studies of solid-state phenomena, particularly in the area of crystal imperfections, have involved the use of melt-grown NaCl single crystals. Quite often trace impurities in these materials have had a prominent effect on these phenomena. Trace amounts of hydroxide ion have been found in melt-grown NaCl crystals. This paper describes a nondestructive method of neutralizing the hydroxide ion in such crystals. Crystals of similar hydroxide content are maintained at an elevated temperature below the melting point of NaCl in a flowing atmosphere containing. dry hydrogen chloride. Heat treatment is continued until an analysis of the test specimens shows no excess hydroxide ion. A colorimetric method previously described4 is used for this analysis.

Geomorphological assessment of sediment contamination in an urban stream system

USGS Publications Warehouse

Rhoads, B.L.; Cahill, R.A.

1999-01-01

Little is known about the influence of fluvial-geomorphological features on the dispersal of sediment-related contaminants in urban drainage systems. This study investigates the relation between reach-scale geomorphological conditions and network-scale patterns of trace-element concentrations in a partially urbanized stream system in East-Central Illinois, USA Robust statistical analysis of bulk sediment samples reveals levels of Cr, Cu, Pb, Ni, and Zn exceed contamination thresholds in the portion of the watershed in close proximity to potential sources of pollution-in this case storm-sewer outfalls. Although trace-element concentrations decrease rapidly downstream from these sources, substantial local variability in metal levels exists within contaminated reaches. This local variability is related to reach-scale variation in fluvial-geomorphic conditions, which in turn produces variation in the degree of sorting and organic-matter content of bed material. Metal concentrations at contaminated sites also exhibit considerable variability over time. Analytical tests on specific size fractions of material collected at a highly contaminated site indicate that Cr and Ni are concentrated in the 0.063 to 0.250 mm fraction of the sediment. This fraction also has elevated concentration of Zr. SEM analysis shows that the fine sand fraction contains shards of stainless steel within a matrix of zircon sand, an industrial material associated with a nearby alloy casting operation. Samples of suspended load and bedload at the contaminated site also have elevated amounts of trace metals, but concentrations of Ni and Cr in the bedload are less than concentrations in the bed material, suggesting that these trace elements are relatively immobile. Off the other hand, amounts of CU and Zn in the bedload exceed concentrations in the bed material, implying that these trace metals are preferentially mobilized during transport events.

Trace-Element Analysis by Use of PIXE Technique on Agricultural Products

NASA Astrophysics Data System (ADS)

Takagi, A.; Yokoyama, R.; Makisaka, K.; Kisamori, K.; Kuwada, Y.; Nishimura, D.; Matsumiya, R.; Fujita, Y.; Mihara, M.; Matsuta, K.; Fukuda, M.

2009-10-01

In order to examine whether a trace-element analysis by PIXE (Particle Induced X-ray Emission) gives a clue to identify production area of agricultural products, we carried out a study on soy beans as an example. In the present study, a proton beam at the energy of 2.3MeV was provided by Van de Graaff accelerator at Osaka University. We used a Ge detector with Be window to measure X-ray spectra. We prepared sample soy beans from China, Thailand, Taiwan, and 7 different areas in Japan. As a result of PIXE analysis, 5 elements, potassium, iron, zinc, arsenic and rubidium, have been identified. There are clear differences in relative amount of trace-elements between samples from different international regions. Chinese beans contain much more Rb than the others, while there are significant differences in Fe and Zn between beans of Thailand and Taiwan. There are relatively smaller differences among Japanese beans. This result shows that trace-elements bring us some practical information of the region where the product grown.

Carotenoids in floral parts of a narcissus, a daffodil and a tulip

PubMed Central

Valadon, L. R. G.; Mummery, Rosemary S.

1968-01-01

1. The qualitative and quantitative distribution of carotenoids of the floral parts of three monocotyledons, the narcissus Scarlet Elegance, the daffodil King Alfred and the tulip Golden Harvest, were studied. β-Carotene, lutein or epoxy-β-carotenes were usually the main pigments, depending on the floral part and on the flower. When β-carotene was the major pigment there were only small amounts of, or sometimes no, epoxycarotenes. 2. Anthers, stigmas and styles of the three flowers did not possess any specific carotenoids but in some cases contained appreciable amounts of epoxycarotenoids. The possibility that these take part in reproduction is discussed. 3. The generalization that yellow flowers contained large amounts of xanthophylls and only traces of carotenes, whereas deep-orange flowers seemed to be characterized by the presence of large amounts of one carotene, was not always the correct one. It is suggested that the floral parts are yellow or orange depending on what carotenoids are present, which is the major one and the amount of total carotenoids, and also on the presence of other non-carotenoid pigments. 4. Two new probable isomers of 5,6:5′,6′-diepoxy-β-carotene were isolated and found together in various floral parts of the tulip Golden Harvest. PMID:5637355

Examination of the Behavior of Bismuth in Shallow-Level Hydrothermal Ore Systems: Constraints Based on Hydrothermal Experiments at 800°C and 100 MPa

NASA Astrophysics Data System (ADS)

Wilmot, M. S.; Candela, P. A.; Piccoli, P. M.; Simon, A. C.; McDonough, W. F.

2006-05-01

The partitioning of ore metals between melt and crystals affects the concentrations of these metals in an evolving ore fluid, and therefore the efficiency of their removal from the magma by hydrothermal processes. Some porphyry-type W-Mo deposits contain recoverable amounts of Bi, whereas others contain only trace amounts. In order to determine the magmatic controls on the ratio of Bi to other commodities in these and other deposits, we examined the partitioning behavior of bismuth between melt, minerals and aqueous phases. Hydrothermal experiments were performed by using externally heated cold seal vessels and employing a double capsule technique. Experiments contained 40 mg of Bishop Tuff glass (SiO2 = 74% ) and 40 mg of either magnetite or pyrrhotite. Bi was added as elemental Bi (< 1 mg). Two different aqueous solutions were used. Initially, the added aqueous phase comprised the solutes HCl, KCl and NaCl in a molar1:1:1 ratio, with a bulk salinity of 10 wt % NaCl eq. The aqueous phase for later experiments contained only the solutes KCl and NaCl in a 1:1 molar ratio. Pre-fractured quartz was added to the experiments to trap fluid inclusions at run PTX conditions. Experiments were performed in Au or Pt capsules held inside Rene 41 cold-seal vessels at 800°C and 100 MPa for durations of up to 36 hours. Analytical data have been collected from the run product solids by using an electron probe microanalyzer (major and trace elements) and laser ablation inductively coupled plasma mass spectrometry (trace elements). Bi in Mt is found in concentrations up to 100 ppm, with higher concentrations in runs where Po decomposed to form magnetite. The Bi concentration in the glass ranges up to 100 ppm. In the Po-bearing runs, data were only collected from Po grains in the experiments containing the HCl-free aqueous solution (the Po grains in the other experiments were too small to analyze). Pyrrhotite contained 10-20 ppm Bi, whereas the glass contained 5-10 ppm. Preliminary Nernst- type partition coefficients for Bi between Mt and melt and Po and melt are approximately 5 and 2, respectively. These data reveal that Bi is only slightly compatible in Mt and Po, and that the Po/melt partition coefficient for Bi is much lower than for Cu, Ag and Au, and is comparable to Mn and Zn. Additional experiments are in progress to more compare the partitioning of Bi with that of W and Mo.

Experimental investigations about the effect of trace amount of propane on the formation of mixed hydrates of methane and propane

NASA Astrophysics Data System (ADS)

Cai, W.; Lu, H.; Huang, X.

2016-12-01

In natural gas hydrates, some heavy hydrocarbons are always detected in addition to methane. However, it is still not well understood how the trace amount of heavy gas affect the hydrate properties. Intensive studies have been carried out to study the thermodynamic properties and structure types of mixed gases hydrates, but comparatively few investigations have been carried out on the cage occupancies of guest molecules in mixed gases hydrates. For understanding how trace amount of propane affects the formation of mixed methane-propane hydrates, X-ray diffraction, Raman spectroscopy, and gas chromatography were applied to the synthesized mixed methane-propane hydrate specimens, to get their structural characteristics (structure type, structural parameters, cage occupancy, etc.) and gas compositions. The mixed methane-propane hydrates were prepared by reacting fine ice powders with various gas mixtures of methane and propane. When the propane content was below 0.4%, the hydrates synthesized were found containing both sI methane hydrate and sII methane-propane hydrate; while the hydrates were found always sII when propane was over certain content. Detail studies about the cage occupancies of propane and methane in sII hydrate revealed that: 1) with the increase in propane content of methane-propane mixture, the occupancy of propane in large cage increased as accompanied with the decrease in methane occupancy in large cage, however the occupancy of methane in small cage didn't experience significant change; 2) temperature and pressure seemed no obvious influence on cage occupancy.

Trace element abundances in major minerals of Late Permian coals from southwestern Guizhou province, China

USGS Publications Warehouse

Zhang, Jiahua; Ren, D.; Zheng, C.; Zeng, R.; Chou, C.-L.; Liu, J.

2002-01-01

Fourteen samples of minerals were separated by handpicking from Late Permian coals in southwestern Guizhou province, China. These 14 minerals were nodular pyrite, massive recrystallized pyrite, pyrite deposited from low-temperature hydrothermal fluid and from ground water; clay minerals; and calcite deposited from low-temperature hydrothermal fluid and from ground water. The mineralogy, elemental composition, and distribution of 33 elements in these samples were studied by optical microscopy, scanning electron microscope equipped with energy-dispersive X-ray spectrometer (SEM-EDX), X-ray diffraction (XRD), cold-vapor atomic absorption spectrometry (CV-AAS), atomic fluorescence spectrometry (AFS), inductively coupled-plasma mass spectrometry (ICP-MS), and ion-selective electrode (ISE). The results show that various minerals in coal contain variable amounts of trace elements. Clay minerals have high concentrations of Ba, Be, Cs, F, Ga, Nb, Rb, Th, U, and Zr. Quartz has little contribution to the concentration of trace elements in bulk coal. Arsenic, Mn, and Sr are in high concentrations in calcite. Pyrite has high concentrations of As, Cd, Hg, Mo, Sb, Se, Tl, and Zn. Different genetic types of calcite in coal can accumulate different trace elements; for example Ba, Co, Cr, Hg, Ni, Rb, Sn, Sr, and Zn are in higher concentrations in calcite deposited from low-temperature hydrothermal fluid than in that deposited from ground water. Furthermore, the concentrations of some trace elements are quite variable in pyrite; different genetic types of pyrites (Py-A, B, C, D) have different concentrations of trace elements, and the concentrations of trace elements are also different in pyrite of low-temperature hydrothermal origin collected from different locations. The study shows that elemental concentration is rather uniform in a pyrite vein. There are many micron and submicron mosaic pyrites in a pyrite vein, which is enriched in some trace elements, such as As and Mo. The content of trace element in pyrite vein depends upon the content of mosaic pyrite and of trace elements in it. Many environmentally sensitive trace elements are mainly contained in the minerals in coal, and hence the physical coal cleaning techniques can remove minerals from coal and decrease the emissions of potentially hazardous trace elements. ?? 2002 Elsevier Science B.V. All rights reserved.

Calcium Chloride in Neonatal Parenteral Nutrition Solutions with and without Added Cysteine: Compatibility Studies Using Laser and Micro-Flow Imaging Methodology.

PubMed

Huston, Robert K; Christensen, J Mark; Alshahrani, Sultan M; Mohamed, Sumeia M; Clark, Sara M; Nason, Jeffrey A; Wu, Ying Xing

2015-01-01

Previous studies of compatibility of calcium chloride (CaCl2) and phosphates have not included particle counts in the range specified by the United States Pharmacopeia. Micro-flow imaging techniques have been shown to be comparable to light obscuration when determining particle count and size in pharmaceutical solutions. The purpose of this study was to do compatibility testing for parenteral nutrition (PN) solutions containing CaCl2 using dynamic light scattering and micro-flow imaging techniques. Solutions containing TrophAmine (Braun Medical Inc, Irvine, CA), CaCl2, and sodium phosphate (NaPhos) were compounded with and without cysteine. All solutions contained standard additives to neonatal PN solutions including dextrose, trace metals, and electrolytes. Control solutions contained no calcium or phosphate. Solutions were analyzed for particle size and particle count. Means of Z-average particle size and particle counts of controls were determined. Study solutions were compared to controls and United States Pharmacopeia (USP) Chapter 788 guidelines. The maximum amount of Phos that was compatible in solutions that contained at least 10 mmol/L of Ca in 2.5% amino acids (AA) was determined. Compatibility of these solutions was verified by performing analyses of 5 repeats of these solutions. Microscopic analyses of the repeats were also performed. Amounts of CaCl2 and NaPhos that were compatible in solutions containing 1.5%, 2%, 2.5%, and 3% AA were determined. The maximum amount of NaPhos that could be added to TrophAmine solutions of > = 2.5% AA containing at least 10 mmol/L of CaCl2 was 7.5 mmol/L. Adding 50 mg/dL of cysteine increased the amount of NaPhos that could be added to solutions containing 10 mmol/L of CaCl2 to 10 mmol/L. Calcium chloride can be added to neonatal PN solutions containing NaPhos in concentrations that can potentially provide an intravenous intake of adequate amounts of calcium and phosphorus.

Chemical stability study of vitamins thiamine, riboflavin, pyridoxine and ascorbic acid in parenteral nutrition for neonatal use

PubMed Central

2011-01-01

Background The objective of this work was to study the vitamins B1, B2, B6 and C stability in a pediatric formulation containing high amounts of calcium in the presence of organic phosphate, amino acids, glucose, sodium chloride, magnesium sulfate, pediatric vitamins and trace elements under different conditions using developed and validated analytical methods. Methods The study was carried out during 72 h with formulations packaged in recommended storage temperature (4°C) and 25°C, with and without photoprotection. Results The results showed that the methodologies used for assessing the chemical stability of vitamins B1, B2, B6 and C in the formulation were selective, linear, precise and accurate. The vitamins could be considered stable in the formulation during the three days of study if stored at 4°C. When stored at 25°C vitamin C presented instability after 48 h. Conclusion The pediatric formulation containing high amount of calcium in the presence of organic phosphate, amino acids, glucose, sodium chloride, magnesium sulphate, pediatric vitamins and trace elements packaged in bag-type trilaminate presented a shelf life of the 72 h, when maintained under refrigeration, between 2°C and 8°C. This shelf life was measured considering the vitamins studied. Further studies are needed including all the vitamins present in this formulation. PMID:21569609

Lipids of Pseudomonas aeruginosa Cells Grown on Hydrocarbons and on Trypticase Soy Broth1

PubMed Central

Edmonds, Paul; Cooney, J. J.

1969-01-01

Lipids were extracted from cells of Pseudomonas aeruginosa grown on a pure hydrocarbon (tridecane), mixed hydrocarbons (JP-4 jet fuel), and on Trypticase Soy Broth. Total lipids produced from each substrate represented from 7.1 to 8.2% of cellular dry weight, of which 5.0 to 6.4% were obtained before cellular hydrolysis (free lipids) and 1.7 to 2.0% were extracted after cellular hydrolysis (bound lipids). Free lipids from cells grown on each medium were separated into four fractions by thin-layer chromatography. All fractions were present in cells from each type of medium, and the “neutral fraction” constituted the largest fraction. The fatty acid composition of free lipids was determined by gas-liquid chromatography. Cells grown on each medium contained saturated and unsaturated C14 to C20 fatty acids. Trace amounts of C13 fatty acids were found in tridecane-grown cells. Saturated C16 and C18 were the major acids present in all cells. Quantitative differences were found in fatty acids produced on the three media, but specific correlations between substrate carbon sources and fatty acid content of cells were not evident. Tridecane-grown cells contained only traces of C13 acid and small amounts of C15 and C17 acids, suggesting that the organism's fatty acids were derived from de novo synthesis rather than by direct incorporation of the hydrocarbon. PMID:4976464

pH-dependent release of trace elements including platinum group elements (PGEs) from gasoline and diesel catalysts

NASA Astrophysics Data System (ADS)

Sucha, Veronika; Mihaljevic, Martin; Ettler, Vojtech; Strnad, Ladislav

2014-05-01

The release of trace metals and platinum group elements (PGEs) from automobile exhaust catalysts represents a remarkable source of higly dispersed environmental contamination. Especially, PGEs have shown increasing research interest due to their possible bioaccessibility. In our research, we focused on leaching behaviour of trace metals from gasoline and diesel automobile catalysts. While catalysts for gasoline engines contain a mixture of Pt-Pd-Rh or Pd-Rh, catalysts for diesel engines are composed only of Pt. We used dust from two crushed gasoline and two crushed diesel catalysts (new and aged). The dust of gasoline catalysts contains significant concentrations of Pt (700 mg.kg-1), Pd (11 000 mg.kg-1) and Rh (700 mg.kg-1). And the dust of diesel catalysts are composed of Pt (3 900 mg.kg-1) and they contains negligible amounts of Pd dan Rh (< 0.5 mg.kg-1, < 0.1 mg.kg-1, respectively). To evaluate leaching of trace metals from dust we used pH-stat leaching test according to the European standard CEN/TS 14997. The concentrations of cations: PGEs (Pt, Pd a Rh), K, Na, Ca, Mg, Al, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, Pb, La and Ce were determined by inductively coupled plasma mass spectrometry (ICP-MS) and atomic absorption spectrometry (AAS), and anions: F-, Cl-, SO42- and NO3- by high-performance liquid chromatography. Although the dusts from catalysts were relatively stable to acid/base influence, the leaching of trace metals from catalysts showed a dependence on pH. Generally, the highest concentrations were released under acidic conditions. The leaching of PGEs was higher for Pt in diesel catalysts and for Pd and Rh in gasoline catalysts. The highest concentrations of Zn and Pb were observed in old catalysts. The rare earth metals were released more from gasoline catalysts. Catalysts particles represent health risk especially with respect to their PGEs contents.

Map showing reconnaissance geochemistry in the gold-pyrophyllite belt of northwestern Moore County, North Carolina

USGS Publications Warehouse

Lesure, Frank G.

1981-01-01

Traces of gold and molybdenum are widely disseminated in an area approximately 35 km long and 10 km wide in northwestern Moore County, N.C.  At least 2540 oz. of gold were recovered from 16 or more mines and prospects between 1880 and 1910.  One hundred and ninety rock samples out of 244 collected from old gold mines, pyrophyllite deposits and along roads contain gold quantities ranging from 0.02 to 2.4 parts per million.  In addition, 43 samples out of the 244 taken contain molybdenum in amounts ranging from 4 to 500 parts per million.

Removal of uranium from aqueous HF solutions

DOEpatents

Pulley, Howard; Seltzer, Steven F.

1980-01-01

This invention is a simple and effective method for removing uranium from aqueous HF solutions containing trace quantities of the same. The method comprises contacting the solution with particulate calcium fluoride to form uranium-bearing particulates, permitting the particulates to settle, and separting the solution from the settled particulates. The CaF.sub.2 is selected to have a nitrogen surface area in a selected range and is employed in an amount providing a calcium fluoride/uranium weight ratio in a selected range. As applied to dilute HF solutions containing 120 ppm uranium, the method removes at least 92% of the uranium, without introducing contaminants to the product solution.

Solid phase microextraction field kit

DOEpatents

Nunes, Peter J.; Andresen, Brian D.

2005-08-16

A field kit for the collection, isolation and concentration of trace amounts of high explosives (HE), biological weapons (BW) and chemical weapons (CW) residues in air, soil, vegetation, swipe, and liquid samples. The field kit includes a number of Solid Phase Microextraction (SPME) fiber and syringe assemblies in a hermetically sealed transportation container or tubes which includes a sampling port, a number of extra SPME fiber and syringe assemblies, the fiber and syringe assemblies including a protective cap for the fiber, and an extractor for the protective cap, along with other items including spare parts, protective glove, and an instruction manual, all located in an airtight container.

Development of a selective and sensitive flotation method for determination of trace amounts of cobalt, nickel, copper and iron in environmental samples.

PubMed

Karimi, H; Ghaedi, M; Shokrollahi, A; Rajabi, H R; Soylak, M; Karami, B

2008-02-28

A simple, selective and rapid flotation method for the separation-preconcentration of trace amounts of cobalt, nickel, iron and copper ions using phenyl 2-pyridyl ketone oxime (PPKO) has been developed prior to their flame atomic absorption spectrometric determinations. The influence of pH, amount of PPKO as collector, type and amount of eluting agent, type and amount of surfactant as floating agent and ionic strength was evaluated on the recoveries of analytes. The influences of the concomitant ions on the recoveries of the analyte ions were also examined. The enrichment factor was 93. The detection limits based on 3 sigma for Cu, Ni, Co and Fe were 0.7, 0.7, 0.8, and 0.7 ng mL(-1), respectively. The method has been successfully applied for determination of trace amounts of ions in various real samples.

Metabolic measures of male southern toads (Bufo terrestris) exposed to coal combustion waste

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

Ward, C.K.; Appel, A.G.; Mendonca, M.T.

2006-03-15

Southern toads (Bufo terrestris) are found in coal fly ash collection basins associated with coal-burning electrical power plants. These basins contain large amounts of trace metals and organisms found in these basins are known to accumulate large quantities of metals. Studies on a variety of organisms exposed to trace metals found that they experience a significant increase in standard metabolic rate. We experimentally exposed southern toads to metal-contaminated sediment and food and measured changes in standard and exercise metabolic rates as well as changes in body, liver and muscle mass, blood glucose, and corticosterone. We found that toads exposed tomore » trace metal contamination gained significantly less mass (18.3%) than control toads (31.3%) when food was limited and experienced significantly decreased RQ after exercise. However, contaminated toads did not experience changes in standard or exercise metabolic rates, plasma glucose levels, and hepatic or muscle percentage indices whether food was limited or not.« less

Partition/Ion-Exclusion Chromatographic Ion Stacking for the Analysis of Trace Anions in Water and Salt Samples by Ion Chromatography.

PubMed

Akter, Fouzia; Saito, Shingo; Tasaki-Handa, Yuiko; Shibukawa, Masami

2018-01-01

A new analytical methodology for a simple and efficient on-line preconcentration of trace inorganic anions in water and salt samples prior to ion chromatographic determination is proposed. The preconcentration method is based on partition/ion-exclusion chromatographic ion stacking (PIEC ion stacking) with a hydrophilic polymer gel column containing a small amount of fixed anionic charges. The developed on-line PIEC ion stacking-ion chromatography method was validated by recovery experiments for the determination of nitrate in tap water in terms of both accuracy and precision, and the results showed the reliability of the method. The method proposed was also successfully applied to the determination of trace impurity nitrite and nitrate in reagent-grade salts of sodium sulfate. A low background level can be achieved since pure water is used as the eluant for the PIEC ion stacking. It is possible to reach sensitive detection at sub-μg L -1 levels by on-line PIEC ion stacking-ion chromatography.

Variations in the chemical properties of landfill leachate

NASA Astrophysics Data System (ADS)

Chu, L. M.; Cheung, K. C.; Wong, M. H.

1994-01-01

Landfill leachates were collected and their chemical properties analyzed once every two months over a ten-month period from the Gin Drinkers' Bay (GDB) and Junk Bay (JB) landfills. The contents of solids, and inorganic and organic components fluctuated considerably with time. In general, the chemical properties of the two leachates correlated negatively ( P<0.05) with the amounts of rainfall prior to the sampling periods. However, magnesium and pH of the leachates remained relatively constant with respect to sampling time. The JB leachate contained higher average contents of solids and inorganic and organic matter than those of GDB with the exception of trace metals. Trace metals were present in the two leachates in trace quantities (<1.0 mg/liter). The concentrations of average ammoniacal nitrogen were 1040 and 549 mg/liter, while chemical oxygen demand (COD) values were 767 and 695 mg/liter for JB and GDB leachates, respectively. These results suggest that the leachates need further treatment before they can be discharged to the coastal waters.

Column amounts of trace gases from ground based FTIR measurements in the late north polar winters 1990 and 1991

NASA Technical Reports Server (NTRS)

Adrian, Gabriele; Blumenstock, Thomas; Fischer, Herbert; Frank, Eckard; Gerhardt, Lothar; Gulde, Thomas; Maucher, Guido; Oelhaf, Hermann; Thomas, Peter; Trieschmann, Olaf

1994-01-01

Two FTIR spectrometers were employed in the late winters 1990 and 1991 in Esrange, North Sweden, and in Ny Aalesund, Spitsbergen to detect zenith column amounts of several trace gases. Time series of column amounts of the trace gases O3, N2O, CH4, HNO3, NO2, CHl, and HF have been derived from the measured spectra. Additionally, some information on the vertical distribution of HCl could be obtained by analyzing the spectral line shapes. The results are interpreted in terms of dynamical and chemical processes.

Oil residue contamination of continental shelf sediments of the Gulf of Mexico.

PubMed

Harding, V; Camp, J; Morgan, L J; Gryko, J

2016-12-15

We have investigated the distribution of a heavy oil residue in the coastal sediments of the Gulf of Mexico. The amount of the contamination was determined by high-temperature pyrolysis coupled with the Gas Chromatography-Mass Spectrometry (GCMS) of air-dried sediments. The pyrolysis products contain straight-chain saturated and unsaturated hydrocarbons, such as dodecane and 1-dodecene, resulting in a very characteristic pattern of double peaks in the GCMS. Hydrocarbons containing 8 to 23 carbon atoms were detected in the pyrolysis products. Using thermal pyrolysis we have found that the sediment samples collected along Texas, Louisiana, and Mississippi shores contain no detectable traces of oil residue, but most of the samples collected along Alabama and Florida shores contain ~200ppm of heavy oil residue. Copyright © 2016 Elsevier Ltd. All rights reserved.

Isolation, purification and some structural features of the mucilaginous exudate from Musa paradisiaca.

PubMed

Mondal, S K; Ray, B; Thakur, S; Ghosal, P K

2001-03-01

The water-soluble polysaccharides isolated from the vascular gel of Musa paradisiaca, were fractionated via anion exchange chromatography into four fractions. Fractionated polymers contained arabinose, xylose and galacturonic acid as major sugars, together with traces of galactose, rhamnose, mannose and glucose residues. Methylation analysis revealed the presence of a highly branched arabinoxylan with a significant amount of terminal arabinopyranosyl units and an arabinogalactan type I pectin. Periodate oxidation studies supported the results of methylation analysis.

High temperature sorbents for oxygen

NASA Technical Reports Server (NTRS)

Sharma, Pramod K. (Inventor)

1994-01-01

A sorbent capable of removing trace amounts of oxygen (ppt) from a gas stream at a high temperature above 200 C comprising a porous alumina silicate support, such as zeolite, containing from 1 to 10 percent by weight of ion exchanged transition metal, such as copper or cobalt ions, and 0.05 to 1.0 percent by weight of an activator selected from a platinum group metal such as platinum is described. The activation temperature, oxygen sorption, and reducibility are all improved by the presence of the platinum activator.

Natural Transmutation of Actinides via the Fission Reaction in the Closed Thorium-Uranium-Plutonium Fuel Cycle

NASA Astrophysics Data System (ADS)

Marshalkin, V. Ye.; Povyshev, V. M.

2017-12-01

It is shown for a closed thorium-uranium-plutonium fuel cycle that, upon processing of one metric ton of irradiated fuel after each four-year campaign, the radioactive wastes contain 54 kg of fission products, 0.8 kg of thorium, 0.10 kg of uranium isotopes, 0.005 kg of plutonium isotopes, 0.002 kg of neptunium, and "trace" amounts of americium and curium isotopes. This qualitatively simplifies the handling of high-level wastes in nuclear power engineering.

Very high-pressure orogenic garnet peridotites

PubMed Central

Liou, J. G.; Zhang, R. Y.; Ernst, W. G.

2007-01-01

Mantle-derived garnet peridotites are a minor component in many very high-pressure metamorphic terranes that formed during continental subduction and collision. Some of these mantle rocks contain trace amounts of zircon and micrometer-sized inclusions. The constituent minerals exhibit pre- and postsubduction microstructures, including polymorphic transformation and mineral exsolution. Experimental, mineralogical, petrochemical, and geochronological characterizations using novel techniques with high spatial, temporal, and energy resolutions are resulting in unexpected discoveries of new phases, providing better constraints on deep mantle processes. PMID:17519341

Trace Metals Derived from Electronic Cigarette (ECIG) Generated Aerosol: Potential Problem of ECIG Devices That Contain Nickel

PubMed Central

Palazzolo, Dominic L.; Crow, Andrew P.; Nelson, John M.; Johnson, Robert A.

2017-01-01

Introduction: ECIGs are currently under scrutiny concerning their safety, particularly in reference to the impact ECIG liquids (E-liquids) have on human health. One concern is that aerosolized E-liquids contain trace metals that could become trapped in respiratory tissues and induce pathology. Methods: To mimic this trapping, peristaltic pumps were used to generate and transport aerosol onto mixed cellulose ester (MCE) membranes where aluminum (Al), arsenic (As), cadmium (Cd), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) were subsequently captured and quantified. The presence of trace metals on unexposed MCE membranes and on MCE membranes exposed to mainstream smoke served as control and comparison, respectively. The presence of these metals was also determined from the E-liquid before aerosolization and untouched by the ECIG device. All metals were quantified using ICP-MS. The ECIG core assembly was analyzed using scanning electron microscopy with elemental analysis capability. Results: The contents (μg) of Al, As, Cd, Cu, Fe, Mn, Ni, Pb, and Zn on control MCE membranes were 1.2 ± 0.2, 0.050 ± 0.002, 0.047 ± 0.003, 0.05 ± 0.01, 0.001 ± 0.001, 0.16 ± 0.04, 0.005 ± 0.003, 0.014 ± 0.006, and 0.09 ± 0.02, respectively. The contents of all trace metals on MCE membranes exposed to aerosol were similar to controls, except Ni which was significantly (p < 0.01) higher (0.024 ± 0.004 μg). In contrast, contents of Al, As, Fe, Mn, and Zn on MCE membranes exposed to smoke were significantly higher (p < 0.05) than controls. The contents of Al, As, Cu, Fe, and Mn on smoke-exposed MCE membranes were also significantly higher (p < 0.05) than their content on aerosol-exposed membranes. The contents per cigarette equivalent of metals in E-liquid before aerosolization were negligible compared to amounts of aerosolized E-liquid, except for Fe (0.002 μg before and 0.001 μg after). Elemental analysis of the core assembly reveals the presence of several of these trace metals, especially Al, Fe, Ni, and Zn. Conclusions: In general, from the single ECIG-device/E-liquid combination used, the amount of trace metals from ECIG-generated aerosol are lower than in traditional mainstream smoke, Only Ni in the ECIG-generated aerosol was higher than control. The most probable source of Ni in this aerosol is the core assembly. PMID:28119618

Trace element analysis of human urine collected after administration of Gd-based MRI contrast agents: characterizing spectral interferences using inorganic mass spectrometry

PubMed Central

Steuerwald, Amy J.; Parsons, Patrick J.; Arnason, John G.; Chen, Zhen; Peterson, C. Matthew; Louis, Germaine M. Buck

2013-01-01

Analysis of human urine is commonly used in biomonitoring studies to assess exposure to essential (e.g., Cu, Zn, Se) and non-essential (Pb, Cd, Pt) trace elements. These data are also used in epidemiological studies to evaluate potential associations between trace element exposure and various health outcomes within a population. Today most trace element analyses are typically performed using quadrupole-based inductively coupled plasma mass spectrometry (Q-ICP-MS). However, there is always the potential for spectral interferences with Q-ICP-MS instrumentation, especially when analyzing human specimens that may contain medications and other exogenous substances. Moreover, such xenobiotics may be unknown to the investigators. In a recent study focusing on environmental exposures and endometriosis: Endometriosis: Natural History, Diagnosis, and Outcomes (ENDO Study), urine specimens (n=619) were collected from participating women upon enrollment into the study or prior to surgery or pelvic magnetic resonance imaging (MRI), and analyzed for 21 trace elements by Q-ICP-MS. Here we report on some anomalous results observed for Se and Pt with elevated concentrations up to several orders of magnitude greater than what might be expected based on established reference intervals. Further investigations using Sector Field (SF-) ICP-MS instrumentation led to identification of doubly charged and polyatomic gadolinium (Gd) species traced to a Gd-based contrast agent that was administered to some subjects just prior to urine collection. Specifically, interferences from Gd2+ and several minor polyatomics were identified as interferences on all of the major isotopes of Se including 74Se, 76Se, 77Se, 78Se, 80Se, and 82Se. While trace amounts of Pt were present in the urine, a number of Gd-containing polyatomic species were also evident as major interferences on all isotopes of Pt (190Pt, 192Pt, 194Pt, 195Pt, 196Pt, and 198Pt), including Gd-chlorides, Gd-argides, and Gd-oxides. These observations underscore the importance of considering potential isobaric interferences when interpreting unusual trace element results for clinical specimens. PMID:27397951

Nicotine Levels and Presence of Selected Tobacco-Derived Toxins in Tobacco Flavoured Electronic Cigarette Refill Liquids

PubMed Central

Farsalinos, Konstantinos E.; Gillman, I. Gene; Melvin, Matt S.; Paolantonio, Amelia R.; Gardow, Wendy J.; Humphries, Kathy E.; Brown, Sherri E.; Poulas, Konstantinos; Voudris, Vassilis

2015-01-01

Background. Some electronic cigarette (EC) liquids of tobacco flavour contain extracts of cured tobacco leaves produced by a process of solvent extraction and steeping. These are commonly called Natural Extract of Tobacco (NET) liquids. The purpose of the study was to evaluate nicotine levels and the presence of tobacco-derived toxins in tobacco-flavoured conventional and NET liquids. Methods. Twenty-one samples (10 conventional and 11 NET liquids) were obtained from the US and Greek market. Nicotine levels were measured and compared with labelled values. The levels of tobacco-derived chemicals were compared with literature data on tobacco products. Results. Twelve samples had nicotine levels within 10% of the labelled value. Inconsistency ranged from −21% to 22.1%, with no difference observed between conventional and NET liquids. Tobacco-specific nitrosamines (TSNAs) were present in all samples at ng/mL levels. Nitrates were present almost exclusively in NET liquids. Acetaldehyde was present predominantly in conventional liquids while formaldehyde was detected in almost all EC liquids at trace levels. Phenols were present in trace amounts, mostly in NET liquids. Total TSNAs and nitrate, which are derived from the tobacco plant, were present at levels 200–300 times lower in 1 mL of NET liquids compared to 1 gram of tobacco products. Conclusions. NET liquids contained higher levels of phenols and nitrates, but lower levels of acetaldehyde compared to conventional EC liquids. The lower levels of tobacco-derived toxins found in NET liquids compared to tobacco products indicate that the extraction process used to make these products did not transfer a significant amount of toxins to the NET. Overall, all EC liquids contained far lower (by 2–3 orders of magnitude) levels of the tobacco-derived toxins compared to tobacco products. PMID:25811768

Nicotine levels and presence of selected tobacco-derived toxins in tobacco flavoured electronic cigarette refill liquids.

PubMed

Farsalinos, Konstantinos E; Gillman, I Gene; Melvin, Matt S; Paolantonio, Amelia R; Gardow, Wendy J; Humphries, Kathy E; Brown, Sherri E; Poulas, Konstantinos; Voudris, Vassilis

2015-03-24

Some electronic cigarette (EC) liquids of tobacco flavour contain extracts of cured tobacco leaves produced by a process of solvent extraction and steeping. These are commonly called Natural Extract of Tobacco (NET) liquids. The purpose of the study was to evaluate nicotine levels and the presence of tobacco-derived toxins in tobacco-flavoured conventional and NET liquids. Twenty-one samples (10 conventional and 11 NET liquids) were obtained from the US and Greek market. Nicotine levels were measured and compared with labelled values. The levels of tobacco-derived chemicals were compared with literature data on tobacco products. Twelve samples had nicotine levels within 10% of the labelled value. Inconsistency ranged from -21% to 22.1%, with no difference observed between conventional and NET liquids. Tobacco-specific nitrosamines (TSNAs) were present in all samples at ng/mL levels. Nitrates were present almost exclusively in NET liquids. Acetaldehyde was present predominantly in conventional liquids while formaldehyde was detected in almost all EC liquids at trace levels. Phenols were present in trace amounts, mostly in NET liquids. Total TSNAs and nitrate, which are derived from the tobacco plant, were present at levels 200-300 times lower in 1 mL of NET liquids compared to 1 gram of tobacco products. NET liquids contained higher levels of phenols and nitrates, but lower levels of acetaldehyde compared to conventional EC liquids. The lower levels of tobacco-derived toxins found in NET liquids compared to tobacco products indicate that the extraction process used to make these products did not transfer a significant amount of toxins to the NET. Overall, all EC liquids contained far lower (by 2-3 orders of magnitude) levels of the tobacco-derived toxins compared to tobacco products.

Comparison of Impurities in Charcoal Sorbents Found by Neutron Activation Analysis

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

Doll, Charles G.; Finn, Erin C.; Cantaloub, Michael G.

2013-01-01

Abstract: Neutron activation of gas samples in a reactor often requires a medium to retain sufficient amounts of the gas for analysis. Charcoal is commonly used to adsorb gas and hold it for activation; however, the amount of activated sodium in the charcoal after irradiation swamps most signals of interest. Neutron activation analysis (NAA) was performed on several commonly available charcoal samples in an effort to determine the activation background. The results for several elements, including the dominant sodium element, are reported. It was found that ECN charcoal had the lowest elemental background, containing sodium at 2.65 ± 0.05 ppm,more » as well as trace levels of copper and tungsten.« less

Functionalized dithiocarbamate chelating resin for the removal of Co2+ from simulated wastewater

NASA Astrophysics Data System (ADS)

Shi, Xuewei; Fu, Linwei; Wu, Yanyang; Zhao, Huiling; Zhao, Shuangliang; Xu, Shouhong

2017-12-01

Industrial wastewater that contains trace amounts of heavy metal ions is often seen in petrochemical industry. While this wastewater can not be directly discharged, it is difficult to treat due to the low concentration of metal ions. Introducing chelating reagents into this wastewater for selective ion adsorption, followed by a mechanical separation process, provides an appealing solution. Toward the success of this technology, the development of effective chelating resins is of key importance. In the present work, a chelating resin containing amino and dithiocarbamate groups was reported for the removal of Co(II) metal ions in trace concentrations from simulated wastewater. By investigating the adsorption performance of the chelating resin at different solution pH values, adsorbent dosages, contact time, initial ion concentrations, and adsorption temperatures, the maximum adsorption capacity of the resin for Co(II) was identified to be 24.89 mg g-1 for a 2 g L-1 adsorbent dosage and a pH value of 5. After four adsorption-desorption cycles, 97% of the adsorption capacity of the resin was maintained. The adsorption kinetics and thermodynamics were analyzed and discussed as well.

[Study of free radicals in aqueous humor in glaucoma and cataracts: differences in presence or absence of diabetes mellitus and neovascular glaucoma].

PubMed

Oshida, Eiki; Arai, Kiyomi; Sakai, Miki; Chikuda, Makoto

2014-09-01

This study was conducted for the purpose of comparing differences in the types of free radicals in the aqueous humor of glaucoma and cataract patients. Free radicals in the aqueous humor of 44 glaucoma eyes and 15 cataract eyes were measured by electron spin resonance (ESR), followed by comparing the detection rates. In addition, subgroup analyses were also conducted for the presence or absence of complications of diabetes mellitus (DM) and neovascular glaucoma (NVG) in the patients. Three types of free radicals were measured, ascorbate-free radical (AFR), AFR containing a trace amount of superoxide (SO) (AFR +), and SO containing a trace amount of AFR (SO +). Significant differences were observed in the detection rates of each type between the glaucoma group (maximum SO +) and the cataract group (maximum AFR), between the DM group (maximum SO +) and the non-DM group (maximum AFR) in the glaucoma, and between the DM group (maximum AFR +) and the non-DM group (maximum AFR) in the cataract. SO + was detected in all cases of NVG regardless of whether they were DM or non-DM. Glaucoma cases are more susceptible to the generation of SO in the aqueous humor than cataracts, and they are more liable to occur in DM than in non-DM in both glaucoma and cataract cases. This study suggest an evidence for a strong correlation with SO and vascularization in NVG.

Induced Autolysis of Aspergillus oryzae (A. niger group)

PubMed Central

Emiliani, Ezio; de Davie, I. Ucha

1962-01-01

The examination of substances formed during induced autolysis by Aspergillus niger was continued in this work, which dealt in particular with carbohydrates. The autolysate contained a large amount of d-glucose (14 to 20% dry wt) and traces of glycolic aldehyde, dihydroxyacetone, ribose, xylose, and fructose. It also contained glycopeptides (about 10% dry wt), which were split from the cell wall during autolysis and which differed from one another in their level of polymerization and their composition. They were constituted by glucose and mannose, glucose and galactose, or mannose, glucose, and galactose (mannose being the most abundant in this case), and amino acids (chiefly alanine, serine, glutamic acid, and aspartic acid). During autolysis, only a part of the cell wall was dissolved, since it retained its shape. Upon further chemical hydrolysis, it produced mostly glucose and glucosamine, and smaller amounts of mannose, galactose, and amino acids. Presumably, glucomannoproteins and glucogalactoproteins were present in the intact cell as a macromolecular complex, constituting, together with chitin, the major part of the cell wall of Aspergillus. PMID:16349623

Converting citrus wastes into value-added products: Economic and environmently friendly approaches.

PubMed

Sharma, Kavita; Mahato, Neelima; Cho, Moo Hwan; Lee, Yong Rok

2017-02-01

Citrus fruits, including oranges, grapefruits, lemons, limes, tangerines, and mandarins, are among the most widely cultivated fruits around the globe. Its production is increasing every year due to rising consumer demand. Citrus-processing industries generate huge amounts of wastes every year, and citrus peel waste alone accounts for almost 50% of the wet fruit mass. Citrus waste is of immense economic value as it contains an abundance of various flavonoids, carotenoids, dietary fiber, sugars, polyphenols, essential oils, and ascorbic acid, as well as considerable amounts of some trace elements. Citrus waste also contains high levels of sugars suitable for fermentation for bioethanol production. However, compounds such as D-limonene must be removed for efficient bioethanol production. The aim of the present article was to review the latest advances in various popular methods of extraction for obtaining value-added products from citrus waste/byproducts and their potential utility as a source of various functional compounds. Copyright © 2016 Elsevier Inc. All rights reserved.

Levels of 2,3-diphosphoglycerate in Friend leukaemic cells.

PubMed

Yeoh, G C

1980-05-08

Most cells are thought to contain trace amounts of 2,3-diphosphoglycerate (DPG), as it acts as a cofactor in the interconversion of 2-phosphoglycerate and 3-phosphoglycerate by the glycolytic enzyme phosphoglyceromutase. DPG is synthesized from 1,3-diphosphoglycerate by the action of diphosphoglycerate mutase. Lowry et al. reported levels of 29 mumol DPG per kg wet weight brain tissue which is approximately 3 pmol per 10(8) cells, assuming that 1 g of brain tissue contains 10(9) cells. In contrast, erythroid cells contain 50-100 nmol DPG per 10(8) cells, depending on the species and the stage of development. This is of the order of a 1,000-fold more DPG compared with non-erythroid cells. In red cells DPG concentration modulates the binding of oxygen to haemoglobin. I show here that erythroid precurser cells also contain markedly raised levels of DPG.

Differentiation of farmed and wild turbot (Psetta maxima): proximate chemical composition, fatty acid profile, trace minerals and antimicrobial resistance of contaminant bacteria.

PubMed

Martínez, B; Miranda, J M; Nebot, C; Rodriguez, J L; Cepeda, A; Franco, C M

2010-10-01

The proximate, cholesterol, fatty acid and trace mineral compositions in the flesh of farmed and wild turbot (Psetta maxima) were evaluated. Additionally, the potential influence of the use of antimicrobial agents in the bacteria carried by farmed turbot was investigated. For this purpose, a total of 144 Pseudomonas spp. and 127 Aeromonas spp. were isolated and tested for their susceptibility to 12 antimicrobials by a disk diffusion method. Farmed turbot contained higher fat, cholesterol and calories as well as lower moisture content than its wild counterpart. The fatty acid profile of farmed turbot included higher levels of myristic, pentadecanoic, palmitoleic, gadoleic, cetoleic, linoleic, linolenic, stearidonic, eicosadienoic and eicosapentaenoic acids, and lower levels of stearic, arachidonic, docosapentaenoic and docosahexaenoic acids than its wild counterpart. The proportions of polyunsaturated fatty acids and n-3/n-6 ratios were higher in wild turbot than in farmed turbot. With respect to trace minerals, no toxic levels were found, and higher amounts of Cd, Co, Cu, Fe, Mn, Pb and Zn, as well as lower amounts of Cr, were found in farmed turbot relative to wild turbot. The antimicrobial resistance of Pseudomonas spp. and Aeromonas spp. were quite similar, with only the trimethoprim-sulfamethoxazole resistance of Aeromonas spp. isolated from farmed turbot being higher than those isolated from wild turbot. In the case of ampicillin, Pseudomonas spp. isolated from wild turbot showed higher resistance levels than those of their counterparts isolated from farmed turbot. In conclusion, the nutritional parameters of wild turbot are more adequate with respect to nutritional recommendations, while no differences were observed in food safety derived from trace mineral concentrations or the antimicrobial resistance of bacteria isolated from wild and farmed turbot.

Hydrocyclone/Filter for Concentrating Biomarkers from Soil

NASA Technical Reports Server (NTRS)

Ponce, Adrian; Obenhuber, Donald

2008-01-01

The hydrocyclone-filtration extractor (HFE), now undergoing development, is a simple, robust apparatus for processing large amounts of soil to extract trace amounts of microorganisms, soluble organic compounds, and other biomarkers from soil and to concentrate the extracts in amounts sufficient to enable such traditional assays as cell culturing, deoxyribonucleic acid (DNA) analysis, and isotope analysis. Originally intended for incorporation into a suite of instruments for detecting signs of life on Mars, the HFE could also be used on Earth for similar purposes, including detecting trace amounts of biomarkers or chemical wastes in soils.

A silver nanoislands on silica spheres platform: enriching trace amounts of analytes for ultrasensitive and reproducible SERS detection.

PubMed

Wang, Zhongshun; Feng, Lei; Xiao, Dongyang; Li, Ning; Li, Yao; Cao, Danfeng; Shi, Zuosen; Cui, Zhanchen; Lu, Nan

2017-11-09

The performance of surface-enhanced Raman scattering (SERS) for detecting trace amounts of analytes depends highly on the enrichment of the diluted analytes into a small region that can be detected. A super-hydrophobic delivery (SHD) process is an excellent process to enrich even femtomolar analytes for SERS detection. However, it is still challenging to easily fabricate a low detection limit, high sensitivity and reproducible SHD-SERS substrate. In this article, we present a cost-effective and fewer-step method to fabricate a SHD-SERS substrate, named the "silver nanoislands on silica spheres" (SNOSS) platform. It is easily prepared via the thermal evaporation of silver onto a layer of super-hydrophobic paint, which contains single-scale surface-fluorinated silica spheres. The SNOSS platform performs reproducible detection, which brings the relative standard deviation down to 8.85% and 5.63% for detecting 10 -8 M R6G in one spot and spot-to-spot set-ups, respectively. The coefficient of determination (R 2 ) is 0.9773 for R6G. The SNOSS platform can be applied to the quantitative detection of analytes whose concentrations range from sub-micromolar to femtomolar levels.

A Lagrangian View of Stratospheric Trace Gas Distributions

NASA Technical Reports Server (NTRS)

Schoeberl, M. R.; Sparling, L.; Dessler, A.; Jackman, C. H.; Fleming, E. L.

1998-01-01

As a result of photochemistry, some relationship between the stratospheric age-of-air and the amount of tracer contained within an air sample is expected. The existence of such a relationship allows inferences about transport history to be made from observations of chemical tracers. This paper lays down the conceptual foundations for the relationship between age and tracer amount, developed within a Lagrangian framework. In general, the photochemical loss depends not only on the age of the parcel but also on its path. We show that under the "average path approximation" that the path variations are less important than parcel age. The average path approximation then allows us to develop a formal relationship between the age spectrum and the tracer spectrum. Using the relation between the tracer and age spectra, tracer-tracer correlations can be interpreted as resulting from mixing which connects parts of the single path photochemistry curve, which is formed purely from the action of photochemistry on an irreducible parcel. This geometric interpretation of mixing gives rise to constraints on trace gas correlations, and explains why some observations are do not fall on rapid mixing curves. This effect is seen in the ATMOS observations.

The vectorization of a ray tracing program for image generation

NASA Technical Reports Server (NTRS)

Plunkett, D. J.; Cychosz, J. M.; Bailey, M. J.

1984-01-01

Ray tracing is a widely used method for producing realistic computer generated images. Ray tracing involves firing an imaginary ray from a view point, through a point on an image plane, into a three dimensional scene. The intersections of the ray with the objects in the scene determines what is visible at the point on the image plane. This process must be repeated many times, once for each point (commonly called a pixel) in the image plane. A typical image contains more than a million pixels making this process computationally expensive. A traditional ray tracing program processes one ray at a time. In such a serial approach, as much as ninety percent of the execution time is spent computing the intersection of a ray with the surface in the scene. With the CYBER 205, many rays can be intersected with all the bodies im the scene with a single series of vector operations. Vectorization of this intersection process results in large decreases in computation time. The CADLAB's interest in ray tracing stems from the need to produce realistic images of mechanical parts. A high quality image of a part during the design process can increase the productivity of the designer by helping him visualize the results of his work. To be useful in the design process, these images must be produced in a reasonable amount of time. This discussion will explain how the ray tracing process was vectorized and gives examples of the images obtained.

High Temperature Sorbents for Oxygen

NASA Technical Reports Server (NTRS)

Sharma, Pramod K. (Inventor)

1996-01-01

A sorbent capable of removing trace amounts of oxygen (ppt) from a gas stream at a high temperature above 200 C is introduced. The sorbent comprises a porous alumina silicate support such as zeolite containing from 1 to 10 percent by weight of ion exchanged transition metal such as copper or cobalt ions and 0.05 to 1.0 percent by weight of an activator selected from a platinum group metal such as platinum. The activation temperature, oxygen sorption and reducibility are all improved by the presence of the platinum activator.

Polychlorinated biphenyl contamination of nursing mothers' milk in Michigan

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

Wickizer, T.M.; Brilliant, L.B.; Copeland, R.

As part of an effort to assess the extent and distribution of PCB contamination in the human population of Michigan, PCB levels in the breast milk of Michigan nursing mothers were investigated. All of the 1057 samples collected from 68 counties contained PCB residues ranging from trace amounts to 5.1 ppm. The mean PCB level was 1.496 ppm. The public health significance of PCB contamination in human populations and the implications of PCB contamination of human milk for current breast-feeding practices are discussed. Several precautionary measures for nursing mothers are recommended.

Reactivity of stratospheric aerosols to small amounts of ammonia in the laboratory environment

NASA Technical Reports Server (NTRS)

Hayes, D.; Snetsinger, K.; Ferry, G.; Oberbeck, V.; Farlow, N.

1980-01-01

Trace ammonia in laboratory air reacts easily with sulfuric acid aerosol samples to form crystalline ammonium sulfate. Argon atmospheres, however, protect sampling surfaces from ammonia contamination. It is found that atmospheric aerosols treated in this way contain only sulfuric acid. After an hour exposed to laboratory air, these same samples convert to ammonium sulfate. Aerosol particles have been collected, using argon control, to determine if the absence of crystalline sulfate is common. But so far there is no evidence that aerosols are neutralized by ammonia in the stratosphere.

Baseline study on essential and trace elements in polished rice from South Korea.

PubMed

Jung, Myung Chae; Yun, Seong-Taek; Lee, Jin-Soo; Lee, Jong-Un

2005-09-01

In 2000, 63 (polished) white rice samples were collected in eight administrative areas all over South Korea and analyzed for 16 elements by inductively coupled plasma atomic emission spectrometry (ICP-AES). Potassium had the highest content, next to Mg, Ca, Si, Zn, Na, Al and Fe. Most of the samples contained worldwide average concentrations of essential and trace elements in rice grains reported by various researches. For inter-area differences in those elements in the rice, the statistical analysis showed no significant differences (p > 0.05) among the eight administrative areas, suggesting that inter-area differences were not substantial in most cases. Thus, the present data can be used as national background levels of elements in rice produced in South Korea. Using the published data on daily consumption of rice in South Korea, it was possible to estimate the daily intake of As, Cd, Cu, Pb and Zn via rice. The results showed that a regular consumption of rice produced in Korea plays an important role in accumulation of essential and trace elements in Korean, especially for farm-households consuming relatively large amounts of rice.

Zinc-containing yeast extract promotes nonrapid eye movement sleep in mice.

PubMed

Cherasse, Yoan; Saito, Hitomi; Nagata, Nanae; Aritake, Kosuke; Lazarus, Michael; Urade, Yoshihiro

2015-10-01

Zinc is an essential trace element for humans and animals, being located, among other places, in the synaptic vesicles of cortical glutamatergic neurons and hippocampal mossy fibers in the brain. Extracellular zinc has the potential to interact with and modulate many different synaptic targets, including glutamate and GABA receptors. Because of the central role of these neurotransmitters in brain activity, we examined in this study the sleep-promoting activity of zinc by monitoring locomotor activity and electroencephalogram after its administration to mice. Zinc-containing yeast extract (40 and 80 mg/kg) dose dependently increased the total amount of nonrapid eye movement sleep and decreased the locomotor activity. However, this preparation did not change the amount of rapid eye movement sleep or show any adverse effects such as rebound of insomnia during a period of 24 h following the induction of sleep; whereas the extracts containing other divalent cations (manganese, iron, and copper) did not decrease the locomotor activity. This is the first evidence that zinc can induce sleep. Our data open the way to new types of food supplements designed to improve sleep. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Chemical characterization of seven Large Area Collector particles by SXRF. [cosmic dust composition

NASA Technical Reports Server (NTRS)

Flynn, G. J.; Sutton, S. R.

1991-01-01

Optical microscopy and synchrotron X-ray fluorescence (SXRF) are used to analyze the chemical composition of seven dark-appearing cosmic-dust particles obtained in the stratosphere during NASA Johnson Large Area Collector flights. The experimental setup and procedures are outlined, and the results are presented in extensive tables. Three of the particles had abundances similar to those of chondrites (except for low Ca values in one particle); two had a metallic appearance and spectra dominated by Fe and Zn; one contained Cu and Cr plus small amounts of Fe and Zn; and one had igneous-type abundances of minor and trace elements while containing all of the elements seen in chondritic particles, suggesting it may be of extraterrestrial origin.

Nitrogen fixation system of tungsten-resistant mutants of Azotobacter vinelandii.

PubMed Central

Riddle, G D; Simonson, J G; Hales, B J; Braymer, H D

1982-01-01

Mutants of Azotobacter vinelandii ATCC 12837 were isolated which could fix N2 in the presence of high tungsten concentrations. The most studied of these mutants (WD2) grew well in N-free modified Burk broth containing 10 mM W, whereas the wild type would not grow in this medium. WD2 would also grow in Burk N-free broth at about the same rate as the wild type. WD2 in broth containing W exhibited 22% of the whole cell acetylene reduction activity of the wild type in broth containing Mo and showed a lowered affinity for acetylene. Two-dimensional gel electrophoresis experiments showed that N2-fixing cells of WD2 from broth containing W or Mo did not produce significant amounts of component I of native nitrogenase protein. Electron spin resonance spectra of whole cells and cell-free extracts of WD2 from broth containing W lacked any trace of the g = 3.6 resonance associated with FeMoCo. Images PMID:6956567

Rapid detection of trace amounts of surfactants using nanoparticles in fluorometric assays

NASA Astrophysics Data System (ADS)

Härmä, Harri; Laakso, Susana; Pihlasalo, Sari; Hänninen, Pekka; Faure, Bertrand; Rana, Subhasis; Bergström, Lennart

2010-01-01

Rapid microtiter assays that utilize the time-resolved fluorescence resonance energy transfer or quenching of dye-labeled proteins adsorbed onto the surfaces of polystyrene or maghemite nanoparticles have been developed for the detection and quantification of trace amounts of surfactants at concentrations down to 10 nM.Rapid microtiter assays that utilize the time-resolved fluorescence resonance energy transfer or quenching of dye-labeled proteins adsorbed onto the surfaces of polystyrene or maghemite nanoparticles have been developed for the detection and quantification of trace amounts of surfactants at concentrations down to 10 nM. Electronic supplementary information (ESI) available: Experimental details and Fig. S1 and S2. See DOI: 10.1039/b9nr00172g

Organic cloud condensation nuclei: the effect of phase, surface tension, trace soluble species, and oxidative processing on particle activation.

NASA Astrophysics Data System (ADS)

Broekhuizen, K. E.; Thornberry, T.; Abbatt, J. P.

2003-12-01

The ability of organic aerosols to act as cloud condensation nuclei (CCN) will be discussed. A variety of laboratory experiments will be presented which address several key questions concerning organic particle activation. Does the particle phase impact activation? How does surface tension play a role and can a trace amount of a surface active species impact activation? Does a trace amount of a highly soluble species impact the activation of organic particles of moderate to low solubility? Can the activation properties of organic aerosols be enhanced through oxidative processing? To systematically address these issues, the CCN activity of various diacids such as oxalic, malonic, succinic, adipic and azelaic acid have been studied, as well as the addition of trace amounts of nonanoic acid and ammonium sulfate to examine the roles of surface active and soluble species, respectively. The first examination of the role of oxidative processing on CCN activity has involved investigating the effect of ozone oxidation on the activity of oleic acid particles.

Essential and toxic elements in infant foods from Spain, UK, China and USA.

PubMed

Carbonell-Barrachina, Ángel A; Ramírez-Gandolfo, Amanda; Wu, Xiangchun; Norton, Gareth J; Burló, Francisco; Deacon, Claire; Meharg, Andrew A

2012-09-01

Spanish gluten-free rice, cereals with gluten, and pureed baby foods were analysed for essential macro-elements (Ca and Na), essential trace elements (Fe, Cu, Zn, Mn, Se, Cr, Co and Ni) and non-essential trace elements (As, Pb, Cd and Hg) using ICP-MS and AAS. Baby cereals were an excellent source of most of the essential elements (Ca, Fe, Cu, Mn and Zn). Sodium content was high in pureed foods to improve their flavour; fish products were also rich in Se. USA pure baby rice samples had the highest contents of all studied essential elements, showing a different nutrient pattern compared to those of other countries. Mineral fortification was not always properly stated in the labelling of infant foods. Complementary infant foods may also contain significant amounts of contaminants. The contents of Hg and Cd were low enough to guarantee the safety of these infant foods. However, it will be necessary to identify the source and reduce the levels of Pb, Cr and As in Spanish foods. Pure baby rice samples contained too much: Pb in Spain; As in UK; As, Cr and Ni in USA; and Cr and Cd in China.

Thermal aging of electrolytes used in lithium-ion batteries - An investigation of the impact of protic impurities and different housing materials

NASA Astrophysics Data System (ADS)

Handel, Patricia; Fauler, Gisela; Kapper, Katja; Schmuck, Martin; Stangl, Christoph; Fischer, Roland; Uhlig, Frank; Koller, Stefan

2014-12-01

Thermal degradation products in lithium-ion batteries result mainly from hydrolysis sensitivity of lithium hexafluorophosphate (LiPF6). As organic carbonate solvents contain traces of protic impurities, the thermal decomposition of electrolytes is enhanced. Therefore, resulting degradation products are studied with nuclear magnetic resonance spectroscopy (NMR) and gas chromatography mass spectrometry (GC-MS). The electrolyte contains 1 M LiPF6 in a binary mixture of ethylene carbonate (EC) and diethylene carbonate (DEC) in a ratio of 1:2 (v/v) and is aged at ambient and elevated temperature. The impact of protic impurities, either added as deionized water or incorporated in positive electrode material, upon aging is investigated. Further, the influence of different housing materials on the electrolyte degradation is shown. Difluorophosphoric acid is identified as main decomposition product by NMR-spectroscopy. Traces of other decomposition products are determined by headspace GC-MS. Acid-base and coulometric titration are used to determine the total amount of acid and water content upon aging, respectively. The aim of this investigation is to achieve profound understanding about the thermal decomposition of one most common used electrolyte in a battery-like housing material.

Trace Elements in Ovaries: Measurement and Physiology.

PubMed

Ceko, Melanie J; O'Leary, Sean; Harris, Hugh H; Hummitzsch, Katja; Rodgers, Raymond J

2016-04-01

Traditionally, research in the field of trace element biology and human and animal health has largely depended on epidemiological methods to demonstrate involvement in biological processes. These studies were typically followed by trace element supplementation trials or attempts at identification of the biochemical pathways involved. With the discovery of biological molecules that contain the trace elements, such as matrix metalloproteinases containing zinc (Zn), cytochrome P450 enzymes containing iron (Fe), and selenoproteins containing selenium (Se), much of the current research focuses on these molecules, and, hence, only indirectly on trace elements themselves. This review focuses largely on two synchrotron-based x-ray techniques: X-ray absorption spectroscopy and x-ray fluorescence imaging that can be used to identify the in situ speciation and distribution of trace elements in tissues, using our recent studies of bovine ovaries, where the distribution of Fe, Se, Zn, and bromine were determined. It also discusses the value of other techniques, such as inductively coupled plasma mass spectrometry, used to garner information about the concentrations and elemental state of the trace elements. These applications to measure trace elemental distributions in bovine ovaries at high resolutions provide new insights into possible roles for trace elements in the ovary. © 2016 by the Society for the Study of Reproduction, Inc.

Determination of trace and heavy metals in some commonly used medicinal herbs in Ayurveda.

PubMed

Nema, Neelesh K; Maity, Niladri; Sarkar, Birendra K; Mukherjee, Pulok K

2014-11-01

Traditionally, the herbal drugs are well established for their therapeutic benefits. Depending upon their geographical sources sometimes the trace and heavy metals' content may differ, which may lead to severe toxicity. So, the toxicological and safety assessment of these herbal drugs are one of the major issues in recent days. Eight different plant species including Aloe vera, Centella asiatica, Calendula officinalis, Cucumis sativus, Camellia sinensis, Clitoria ternatea, Piper betel and Tagetes erecta were selected to determine their heavy and trace metals content and thereby to assure their safer therapeutic application. The trace and heavy metals were detected through atomic absorption spectrometry analysis. The selected medicinal plant materials were collected from the local cultivated regions of West Bengal, India, and were digested with nitric acid and hydrochloric acid as specified. Absorbance was measured through atomic absorption spectrometer (AA 303) and the concentration of different trace and heavy metals in the plant samples were calculated. The quantitative determinations were carried out using standard calibration curve obtained by the standard solutions of different metals. The contents of heavy metals were found to be within the prescribed limit. Other trace metals were found to be present in significant amount. Thus, on the basis of experimental outcome, it can be concluded that the plant materials collected from the specific region are safe and may not produce any harmful effect of metal toxicity during their therapeutic application. The investigated medicinal plants contain trace metals such as copper (Cu), chromium (Cr), manganese (Mn), iron (Fe) and nickel (Ni) as well as heavy metals such as arsenic (As), lead (Pb) and mercury (Hg), which were present within the permissible limit. © The Author(s) 2012.

On nutrients and trace metals: Effects from Enhanced Weathering

NASA Astrophysics Data System (ADS)

Amann, T.; Hartmann, J.

2015-12-01

The application of rock flour on suitable land ("Enhanced Weathering") is one proposed strategy to reduce the increase of atmospheric CO2 concentrations. At the same time it is an old and established method to add fertiliser and influence soil properties. Investigations of this method focused on the impact on the carbonate system, as well as on engineering aspects of a large-scale application, but potential side effects were never discussed quantitatively. We analysed about 120,000 geochemically characterised volcanic rock samples from the literature. Applying basic statistics, theoretical release rates of nutrients and potential contaminants by Enhanced Weathering were evaluated for typical rock types. Applied rock material can contain significant amounts of essential or beneficial nutrients (potassium, phosphorus, micronutrients). Their release can partly cover the demand of major crops like wheat, rice or corn, thereby increasing crop yield on degraded soils. However, the concentrations of considered elements are variable within a specific rock type, depending on the geological setting. High heavy metal concentrations are found in (ultra-) basic rocks, the class with the highest CO2 drawdown potential. More acidic rocks contain less or no critical amounts, but sequester less CO2. Findings show that the rock selection determines the capability to supply significant amounts of nutrients, which could partly substitute industrial mineral fertiliser usage. At the same time, the release of harmful trace element has to be considered. Through careful selection of regionally available rocks, benefits could be maximised and drawbacks reduced. The deployment of Enhanced Weathering to sequester CO2 and to ameliorate soils necessitates an ecosystem management, considering the release and fate of weathered elements in plants, soils and water. Cropland with degraded soils would benefit while having a net negative CO2 effect, while other carbon dioxide removal strategies, like afforestation, biofuel production, and biochar application could benefit from Enhanced Weathering side effects, as organic carbon pools are positively influenced.

Levels of iron, silver, zinc, and lead in oranges and avocados from two gold-rich towns compared with levels in an adjacent gold-deficient town

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

Golow, A.A.; Laryea, J.N.

1994-09-01

Fruits such as oranges and avocados are important sources of drinks and food in the Ghanaian Society. If such fruits contain various types of metals they may augument the types and amounts of them in the human body. The metals in fruits may depend on what is in the soils from which they are grown. If the soils contain toxic metals like lead, mercury and cadmium then the consumers may be poisoned as happened in the [open quotes]Ouchi - ouchi[close quotes], disease in Japan and similar episodes. In the area under study, the Geological Survey indicates the presence of 2.5more » ppm of lead, 10 - 20 ppm of copper and less than 15 ppm of nickel. Silver, not reported in commercial amounts, is a byproduct of gold productions at Obuasi. Since copper and nickel are presented in the area traces of silver will certainly occur. In the same manner zinc is usually associated with lead as sulphide of zinc blend trace amounts of it are likely to occur in the area. Of the four metals measured, iron and zinc essential for citrus. The extractable iron and zinc in the area of study were 90 and 1.8 mg/kg, levels on the low side for the healthy growth of crops. The investigation reported here is the comparison of the levels of some metals in oranges and avocados from farms in Obuasi and Konongo with those from farms in Kumasi City. This is a part of a project aimed at finding out differences in the metal contents of various food crops grown in various regions of the country. Konongo and Obuasi have soils which are rich in gold but Kumasi city, which is not too distant from these towns, does not have gold in its soil. 18 refs., 1 tab.« less

Rapid screening of heavy metals and trace elements in environmental samples using portable X-ray fluorescence spectrometer, A comparative study

PubMed Central

McComb, Jacqueline Q.; Rogers, Christian; Han, Fengxiang X.; Tchounwou, Paul B.

2014-01-01

With industrialization, great amounts of trace elements and heavy metals have been excavated and released on the surface of the earth and dissipated into the environments. Rapid screening technology for detecting major and trace elements as well as heavy metals in variety of environmental samples is most desired. The objectives of this study were to determine the detection limits, accuracy, repeatability and efficiency of a X-ray fluorescence spectrometer (Niton XRF analyzer) in comparison with the traditional analytical methods, inductively coupled plasma optical emission spectrometer (ICP-OES) and inductively coupled plasma optical emission spectrometer (ICP-MS) in screening of major and trace elements of environmental samples including estuary soils and sediments, contaminated soils, and biological samples. XRF is a fast and non-destructive method in measuring the total concentration of multi--elements simultaneously. Contrary to ICP-OES and ICP-MS, XRF analyzer is characterized by the limited preparation required for solid samples, non-destructive analysis, increased total speed and high throughout, the decreased production of hazardous waste and the low running costs as well as multi-elemental determination and portability in the fields. The current comparative study demonstrates that XRF is a good rapid non-destructive method for contaminated soils, sediments and biological samples containing higher concentrations of major and trace elements. Unfortunately, XRF does not have sensitive detection limits of most major and trace elements as ICP-OES or ICP-MS but it may serve as a rapid screening tool for locating hot spots of uncontaminated field soils and sediments. PMID:25861136

A dynamic gravimetric standard for trace water.

PubMed

Brewer, P J; Goody, B A; Woods, P T; Milton, M J T

2011-10-01

A system for generating traceable reference standards of water vapor at trace levels between 5 and 2000 nmol/mol has been developed. It can provide different amount fractions of trace water vapor by using continuous accurate measurements of mass loss from a permeation device coupled with a dilution system based on an array of critical flow orifices. An estimated relative expanded uncertainty of ±2% has been achieved for most amount fractions generated. The system has been used in an international comparison and demonstrates excellent comparability with National Metrology Institutes maintaining standards of water vapor in this range using other methods.

Heterodyne method for high specificity gas detection.

NASA Technical Reports Server (NTRS)

Dimeff, J.; Donaldson, R. W.; Gunter, W. D., Jr.; Jaynes, D. N.; Margozzi, A. P.; Deboo, G. J.; Mcclatchie, E. A.; Williams, K. G.

1971-01-01

This paper describes a new technique for measuring trace quantities of gases. The technique involves the use of a reference cell (containing a known amount of the gas being sought) and a sample cell (containing an unknown amount of the same gas) wherein the gas densities are modulated. Light passing through the two cells in sequence is modulated in intensity at the vibrational-rotational lines characteristic of the absorption spectrum for the gas of interest. Since the absorption process is nonlinear, modulating the two absorption cells at two different frequencies gives rise to a heterodyning effect, which in turn introduces sum and difference frequencies in the detected signal. Measuring the ratio of the difference frequency signal for example, to the signal introduced by the reference cell provides a normalized measure of the amount of the gas in the sample cell. The readings produced are thereby independent of source intensity, window transparency, and detector sensitivity. Experimental evaluation of the technique suggests that it should be applicable to a wide range of gases, that it should be able to reject spurious signals due to unwanted gases, and that it should be sensitive to concentrations of the order of 10 to the minus 8th power when used with a sample cell of only 20 cm length.

Flavanol binding of nuclei from tree species.

PubMed

Feucht, W; Treutter, D; Polster, J

2004-01-01

Light microscopy was used to examine the nuclei of five tree species with respect to the presence of flavanols. Flavanols develop a blue colouration in the presence of a special p-dimethylaminocinnamaldehyde (DMACA) reagent that enables those nuclei loaded with flavanols to be recognized. Staining of the nuclei was most pronounced in both Tsuga canadensis and Taxus baccata, variable in Metasequoia glyptostroboides, faint in Coffea arabica and minimal in Prunus avium. HPLC analysis showed that the five species contained substantial amounts of different flavanols such as catechin, epicatechin and proanthocyanidins. Quantitatively, total flavanols were quite different among the species. The nuclei themselves, as studied in Tsuga seed wings, were found to contain mainly catechin, much lower amounts of epicatechin and traces of proanthocyanidins. Blue-coloured nuclei located centrally in small cells were often found to maximally occupy up to 90% of a cell's radius, and the surrounding small rim of cytoplasm was visibly free of flavanols. A survey of 34 gymnosperm and angiosperm species indicated that the first group has much higher nuclear binding capacities for flavanols than the second group.

Forensic trace DNA: a review

PubMed Central

2010-01-01

DNA analysis is frequently used to acquire information from biological material to aid enquiries associated with criminal offences, disaster victim identification and missing persons investigations. As the relevance and value of DNA profiling to forensic investigations has increased, so too has the desire to generate this information from smaller amounts of DNA. Trace DNA samples may be defined as any sample which falls below recommended thresholds at any stage of the analysis, from sample detection through to profile interpretation, and can not be defined by a precise picogram amount. Here we review aspects associated with the collection, DNA extraction, amplification, profiling and interpretation of trace DNA samples. Contamination and transfer issues are also briefly discussed within the context of trace DNA analysis. Whilst several methodological changes have facilitated profiling from trace samples in recent years it is also clear that many opportunities exist for further improvements. PMID:21122102

Macro- and microelement distribution in organs of Glyceria maxima and biomonitoring applications.

PubMed

Klink, Agnieszka; Stankiewicz, Andrzej; Wisłocka, Magdalena; Polechońska, Ludmiła

2014-07-01

The content of nutrients (N, P, K, Ca and Mg) and of trace metals (Fe, Cu, Mn, Zn, Pb, Cd, Co and Ni) in water, bottom sediments and various organs of Glyceria maxima from 19 study sites selected in the Jeziorka River was determined. In general, the concentrations of nutrients recorded in the plant material decreased in the following order: leaf>root>rhizome>stem, while the concentrations of the trace elements showed the following accumulation scheme: root>rhizome>leaf>stem. The bioaccumulation and transfer factors for nutrients were significantly higher than for trace metals. G. maxima from agricultural fields was characterised by the highest P and K concentrations in leaves, and plants from forested land contained high Zn and Ni amounts. However, the manna grass from small localities showed high accumulation of Ca, Mg and Mn. Positive significant correlations between Fe, Cu, Zn, Cd, Co and Ni concentrations in water or sediments and their concentrations in plant indicate that G. maxima may be employed as a biomonitor of trace element contamination. Moreover, a high degree of similarity was noted between self-organizing feature map (SOFM)-grouped sites of comparable quantities of elements in the water and sediments and sites where G. maxima had a corresponding content of the same elements in its leaves. Therefore, SOFM could be recommended in analysing ecological conditions of the environment from the perspective of nutrients and trace element content in different plant species and their surroundings.

Radioisotope tracer studies in the NASA Skylab ethothermic brazing experiment M-552

NASA Technical Reports Server (NTRS)

Braski, D. N.; Adair, H. L.; Kobisk, E. H.

1974-01-01

The first use of radioisotope tracer for mapping flow patterns during brazing of metal components in a space environment (near-zero gravity) proved successful. A nickel ferrule was brazed to a nickel tube with Lithobraze BT (71.8% Ag, 28% Cu, 0.2% Li) which contained a trace amount of radioactive Ag-110. Mapping of the flow of the braze alloy in the annulus formed between the tube and the concentric ferrule was determined by counting the radiation intensity as a function of position in the braze joint. Significant information concerning the thermal history of the braze was determined.

Hemlock Alkaloids in Aloes. Occurrence and Distribution of gamma-Coniceine.

PubMed

Dring, J V; Nash, R J; Roberts, M F; Reynolds, T

1984-10-01

The hemlock alkaloid gamma-coniceine was identified in a number of ALOE species, namely A. GILLILANDII, Reynolds A. BALLYI Reynolds, A. RUSPOLIANA Baker, A. IBITIENSIS Perrier and A. DELTOIDEODONTA Baker. Coniine was identified in A. VIGUIERI Perrier. The levels of gamma-coniceine are higher than those found in CONIUM MACULATUM L. Some species also contained trace amounts of conhydrinone and pseudoconhydrin. Three of the species are Madagascan endemics, one is restricted to Arabia, while the rest are remote from each other in East Africa. Some of the species are loosely related but there is no overall taxonomic affinity between them.

Content and distribution of arsenic, bismuth, lithium and selenium in mineral and synthetic fertilizers and their contribution to soil

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

Senesi, N.; Polemio, M.; Lorusso, L.

1979-01-01

Concentrations of arsenic, bismuth, lithium and selenium were determined by atomic absorption spectrophotometry in 32 samples of commercial fertilizers from various manufacturers and distributors. Arsenic and lithium were detected in all investigated samples, bismuth in 50% of samples and selenium only in two samples. Arsenic content ranged from 2 to 321 ppM; lithium varied from 5 to 0.1 ppM; bismuth was always lower than 0.5 ppM; selenium was detectable at the levels of 10 and 13 ppM. Fertilizers made from rock phosphates contained trace element amounts generally higher than those derived from rock carbonates, synthetic nitrogen fertilizers and potassium sulphate.more » Additions of trace elements from fertilizers applied at common rates to cultivated soils are tabulated and discussed on the basis of the natural soil reserves and toxicity levels for plants. Whereas applications of bismuth resulted always very low to influence the usual soil content and plant uptakes and selenium was only rarely present in fertilizers, lithium and moreover arsenic additions by fertilizers could influence the trace element status in soil, overcoming occasionally the toxicity levels for more sensitive crops.« less

Fate dynamics of environmentally exposed explosive traces.

PubMed

Kunz, Roderick R; Gregory, Kerin E; Aernecke, Matthew J; Clark, Michelle L; Ostrinskaya, Alla; Fountain, Augustus W

2012-04-12

The chemical and physical fates of trace amounts (<50 μg) of explosives containing 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), and pentaerythritol tetranitrate (PETN) were determined for the purpose of informing the capabilities of tactical trace explosive detection systems. From these measurements, it was found that the mass decreases and the chemical composition changes on a time scale of hours, with the loss mechanism due to a combination of sublimation and photodegradation. The rates for these processes were dependent on the explosive composition, as well as on both the ambient temperature and the size distribution of the explosive particulates. From these results, a persistence model was developed and applied to model the time dependence of both the mass and areal coverage of the fingerprints, resulting in a predictive capability for determining fingerprint fate. Chemical analysis confirmed that sublimation rates for TNT were depressed by UV (330-400 nm) exposure due to photochemically driven increases in the molecular weight, whereas the opposite was observed for RDX. No changes were observed for PETN upon exposure to UV radiation, and this was attributed to its low UV absorbance.

Predicting Water Quality Problems Associated with Coal Fly Ash Disposal Facilities Using a Trace Element Partitioning Study

NASA Astrophysics Data System (ADS)

Bhattacharyya, S.; Donahoe, R. J.; Graham, E. Y.

2006-12-01

For much of the U.S., coal-fired power plants are the most important source of electricity for domestic and industrial use. Large quantities of fly ash and other coal combustion by-products are produced every year, the majority of which is impounded in lagoons and landfills located throughout the country. Many older fly ash disposal facilities are unlined and have been closed for decades. Fly ash often contains high concentrations of toxic trace elements such as arsenic, boron, chromium, molybdenum, nickel, selenium, lead, strontium and vanadium. Trace elements present in coal fly ash are of potential concern due to their toxicity, high mobility in the environment and low drinking water MCL values. Concern about the potential release of these toxic elements into the environment due to leaching of fly ash by acid rain, groundwater or acid mine drainage has prompted the EPA to develop national standards under the subtitle D of the Resource Conservation and Recovery Act (RCRA) to regulate ash disposal in landfills and surface impoundments. An attempt is made to predict the leaching of toxic elements into the environment by studying trace element partitioning in coal fly ash. A seven step sequential chemical extraction procedure (SCEP) modified from Filgueiras et al. (2002) is used to determine the trace element partitioning in seven coal fly ash samples collected directly from electric power plants. Five fly ash samples were derived from Eastern Bituminous coal, one derived from Western Sub-bituminous coal and the other derived from Northern Lignite. The sequential chemical extraction procedure gives valuable information on the association of trace elements: 1) soluble fraction, 2) exchangeable fraction, 3) acid soluble fraction, 4) easily reducible fraction, 5) moderately reducible fraction, 6) poorly reducible fraction and 7) oxidizable organics/sulfide fraction. The trace element partitioning varies with the composition of coal fly ash which is influenced by the type of coal burned. Preliminary studies show that in some fly ash samples, significant amounts of As, B, Mo, Se, Sr and V are associated with the soluble and exchangeable fraction, and thus would be highly mobile in the environment. Lead, on the other hand, is mainly associated with the amorphous Fe and Mn oxide fractions and would be highly immobile in oxidizing conditions, but mobile in reducing conditions. Ni and Cr show different associations in different fly ash samples. In most fly ash samples, significant amounts of the trace elements are associated with more stable fractions that do not threaten the environment. The study of trace element partitioning in coal fly ash thus helps us to predict their leaching behavior under various conditions.

Immunoaffinity column as clean-up tool for determination of trace amounts of microcystins in tap water.

PubMed

Tsutsumi, T; Nagata, S; Hasegawa, A; Ueno, Y

2000-07-01

Trace amounts of microcystins (MCs) in drinking water should be monitored because of their potential hazard for human health as an environmental tumor promoter. We describe here a new clean-up tool with immunoaffinity column (IAC) for determination of trace amounts of MCs (from pg to microg/litre) in tap water. The water samples were concentrated with IAC clean-up and MCs levels were determined by HPLC with UV detection or enzyme-linked immunosorbent assay (ELISA). In the combination with HPLC analysis, mean recovery of microcystin-LR (MCLR),-RR and-YR spiked to tap water were 91.8%, 77.3% and 86.4%, respectively, in the range 2.5-100 microg/litre. The chromatogram of MCs-spiked tap water sample cleaned up with IAC showed effective elimination of the impurities compared to that with octadecyl silanized cartridge, which had been cleaned up with a conventional method. Also, in the combination with highly sensitive ELISA, mean recovery of MCLR spiked to tap water was 80% in the range 0.1-1000 ng/litre. The combined methods developed here can detect pg to microg/litre of MCs in tap water. The overall results indicated that IAC will be suitable as a clean-up tool for trace amounts of MCs in tap water.

Reaction Mechanism and Molecular Basis for Selenium/Sulfur Discrimination of Selenocysteine Lyase*

PubMed Central

Omi, Rie; Kurokawa, Suguru; Mihara, Hisaaki; Hayashi, Hideyuki; Goto, Masaru; Miyahara, Ikuko; Kurihara, Tatsuo; Hirotsu, Ken; Esaki, Nobuyoshi

2010-01-01

Selenocysteine lyase (SCL) catalyzes the pyridoxal 5′-phosphate-dependent removal of selenium from l-selenocysteine to yield l-alanine. The enzyme is proposed to function in the recycling of the micronutrient selenium from degraded selenoproteins containing selenocysteine residue as an essential component. The enzyme exhibits strict substrate specificity toward l-selenocysteine and no activity to its cognate l-cysteine. However, it remains unclear how the enzyme distinguishes between selenocysteine and cysteine. Here, we present mechanistic studies of selenocysteine lyase from rat. ESI-MS analysis of wild-type and C375A mutant SCL revealed that the catalytic reaction proceeds via the formation of an enzyme-bound selenopersulfide intermediate on the catalytically essential Cys-375 residue. UV-visible spectrum analysis and the crystal structure of SCL complexed with l-cysteine demonstrated that the enzyme reversibly forms a nonproductive adduct with l-cysteine. Cys-375 on the flexible loop directed l-selenocysteine, but not l-cysteine, to the correct position and orientation in the active site to initiate the catalytic reaction. These findings provide, for the first time, the basis for understanding how trace amounts of a selenium-containing substrate is distinguished from excessive amounts of its cognate sulfur-containing compound in a biological system. PMID:20164179

Distribution of trace levels of therapeutic gallium in bone as mapped by synchrotron x-ray microscopy.

PubMed Central

Bockman, R S; Repo, M A; Warrell, R P; Pounds, J G; Schidlovsky, G; Gordon, B M; Jones, K W

1990-01-01

Gallium nitrate, a drug that inhibits calcium release from bone, has been proven a safe and effective treatment for the accelerated bone resorption associated with cancer. Though bone is a target organ for gallium, the kinetics, sites, and effects of gallium accumulation in bone are not known. We have used synchrotron x-ray microscopy to map the distribution of trace levels of gallium in bone. After short-term in vivo administration of gallium nitrate to rats, trace (nanogram) amounts of gallium preferentially localized to the metabolically active regions in the metaphysis as well as the endosteal and periosteal surfaces of diaphyseal bone, regions where new bone formation and modeling were occurring. The amounts measured were well below the levels known to be cytotoxic. Iron and zinc, trace elements normally found in bone, were decreased in amount after in vivo administration of gallium. These studies represent a first step toward understanding the mechanism(s) of action of gallium in bone by suggesting the possible cellular, structural, and elemental "targets" of gallium. Images PMID:2349224

A first proposal for a general description model of forensic traces

NASA Astrophysics Data System (ADS)

Lindauer, Ina; Schäler, Martin; Vielhauer, Claus; Saake, Gunter; Hildebrandt, Mario

2012-06-01

In recent years, the amount of digitally captured traces at crime scenes increased rapidly. There are various kinds of such traces, like pick marks on locks, latent fingerprints on various surfaces as well as different micro traces. Those traces are different from each other not only in kind but also in which information they provide. Every kind of trace has its own properties (e.g., minutiae for fingerprints, or raking traces for locks) but there are also large amounts of metadata which all traces have in common like location, time and other additional information in relation to crime scenes. For selected types of crime scene traces, type-specific databases already exist, such as the ViCLAS for sexual offences, the IBIS for ballistic forensics or the AFIS for fingerprints. These existing forensic databases strongly differ in the trace description models. For forensic experts it would be beneficial to work with only one database capable of handling all possible forensic traces acquired at a crime scene. This is especially the case when different kinds of traces are interrelated (e.g., fingerprints and ballistic marks on a bullet casing). Unfortunately, current research on interrelated traces as well as general forensic data models and structures is not mature enough to build such an encompassing forensic database. Nevertheless, recent advances in the field of contact-less scanning make it possible to acquire different kinds of traces with the same device. Therefore the data of these traces is structured similarly what simplifies the design of a general forensic data model for different kinds of traces. In this paper we introduce a first common description model for different forensic trace types. Furthermore, we apply for selected trace types from the well established database schema development process the phases of transferring expert knowledge in the corresponding forensic fields into an extendible, database-driven, generalised forensic description model. The trace types considered here are fingerprint traces, traces at locks, micro traces and ballistic traces. Based on these basic trace types, also combined traces (multiple or overlapped fingerprints, fingerprints on bullet casings, etc) and partial traces are considered.

Separation of thorium ions from wolframite and scandium concentrates using graphene oxide.

PubMed

Jankovský, Ondřej; Sedmidubský, David; Šimek, Petr; Klímová, Kateřina; Bouša, Daniel; Boothroyd, Chris; Macková, Anna; Sofer, Zdeněk

2015-10-14

The separation of rare metals from the ores and commercially available compounds is an important issue due to the need of their high purity in advanced materials and devices. Important examples of two highly important elements that co-exist in the ores are scandium and thorium. Scandium containing ores and consequently also commercially available scandium compounds often contain traces of thorium which is very difficult to separate. We used graphene oxide for the selective sorption of thorium ions from scandium and thorium mixtures originating from the mined ores as well as from commercially available scandium salts. Our results showed that graphene oxide has an extreme affinity towards thorium ions. After the sorption process the graphene oxide contained over 20 wt% of thorium while the amount of scandium sorbed on GO was very low. This phenomenon of high sorption selectivity of graphene oxide can be applied in industry for the purification of various chemicals containing scandium and for separation of thorium containing mixtures. Alternatively, this methodology can be used for preconcentration of thorium from low-grade ores and its further use in the new generation of nuclear reactors.

Enhancement in sample collection for the detection of MDMA using a novel planar SPME (PSPME) device coupled to ion mobility spectrometry (IMS).

PubMed

Gura, Sigalit; Guerra-Diaz, Patricia; Lai, Hanh; Almirall, José R

2009-07-01

Trace detection of illicit drugs challenges the scientific community to develop improved sensitivity and selectivity in sampling and detection techniques. Ion mobility spectrometry (IMS) is one of the prominent trace detectors for illicit drugs and explosives, mostly due to its portability, high sensitivity and fast analysis. Current sampling methods for IMS rely on wiping suspected surfaces or withdrawing air through filters to collect particulates. These methods depend greatly on the particulates being bound onto surfaces or having sufficient vapour pressure to be airborne. Many of these compounds are not readily available in the headspace due to their low vapour pressure. This research presents a novel SPME device for enhanced air sampling and shows the use of optimized IMS by genetic algorithms to target volatile markers and/or odour signatures of illicit substances. The sampling method was based on unique static samplers, planar substrates coated with sol-gel polydimethyl siloxane (PDMS) nanoparticles, also known as planar solid-phase microextraction (PSPME). Due to its surface chemistry, high surface area and capacity, PSPME provides significant increases in sensitivity over conventional fibre SPME. The results show a 50-400 times increase in the detection capacity for piperonal, the odour signature of 3,4-methylenedioxymethamphetamine (MDMA). The PSPME-IMS technique was able to detect 600 ng of piperonal in a 30 s extraction from a quart-sized can containing 5 MDMA tablets, while detection using fibre SPME-IMS was not attainable. In a blind study of six cases suspected to contain varying amounts of MDMA in the tablets, PSPME-IMS successfully detected five positive cases and also produced no false positives or false negatives. One positive case had minimal amounts of MDMA resulting in a false negative response for fibre SPME-IMS.

Determination of trace amount of formaldehyde base on a bromate-Malachite Green system.

PubMed

Tang, Yufang; Chen, Hao; Weng, Chao; Tang, Xiaohui; Zhang, Miaoling; Hu, Tao

2015-01-25

A novel catalytic kinetic spectrophotometric method for determination of trace amount of formaldehyde (FA) has been established, based on catalytic effect of trace amount of FA on the oxidation of Malachite Green (MG) by potassium bromate in presence of sulfuric acid medium, and was reported for the first time. The method was monitored by measuring the decrease in absorbance of MG at 617 nm and allowed a precise determination of FA in the range of 0.003-0.08 μg mL(-1), with a limit of detection down to 1 ng mL(-1). The relative standard deviation of 10 replicate measurements was 1.63%. The method developed was approved to be sensitive, selective and accurate, and adopted to determinate free FA in samples directly with good accuracy and reproducibility. Copyright © 2014 Elsevier B.V. All rights reserved.

Morphological Dependence of Element Stoichiometry in the H. americanus Exoskeleton

NASA Astrophysics Data System (ADS)

Mergelsberg, S. T.; Ulrich, R. N.; Dove, P. M.

2016-02-01

The crustacean exoskeleton is a complex biocomposite of inorganic mineral and organic macromolecules that expresses highly divergent morphologies across different taxa. While the structures and compositions of the organic framework show complex links to environmental and developmental pressures, little is known about the mineral chemistry. Previous studies of the cuticle have assumed that magnesium, phosphorous, and other trace metals are largely contained in the inorganic mineral fraction. Due to analytical limitations of structural analyses and in situ spectroscopic methods, the stoichiometry of the organic and inorganic portions could not be resolved. For example, previous Raman and XRD studies conclude the higher concentrations of trace elements, such as P and Mg measured in reinforced structures, e.g. the claw and abdomen, are primarily determined by the mineral fraction. Using the American Lobster (Homarus americanus) as a model organism to establish relationships between body part function and cuticle composition, this study quantified the distributions of Mg and P in the mineral and organic fractions. The experiments were designed to dissolve the exoskeleton of 10 body parts using three types of solutions that were specific to extracting 1) the mineral phase, 2) protein, and 3) polysaccharide. Analysis of the solutions by ICP-OES shows the mineral phase contains magnesium and phosphorous at concentrations sufficient to support the formation of calcium-magnesium and phosphate minerals. The protein fraction of the body parts contains significantly more Mg and P than previously hypothesized, while the levels of P contained in the organic portion are fairly constant. The findings demonstrate the lobster cuticle contains a significant amount of non-mineralized P and Mg that is readily water-soluble in the protein component. However, for those body parts used for defense and food acquisition, such as the claw, the mineral component determines the overall composition of the exoskeleton.

Multiplexed Microsphere Suspension-Array Assay for Urine Mitochondrial DNA Typing by C-Stretch Length in Hypervariable Regions.

PubMed

Aoki, Kimiko; Tanaka, Hiroyuki; Kawahara, Takashi

2018-07-01

The standard method for personal identification and verification of urine samples in doping control is short tandem repeat (STR) analysis using nuclear DNA (nDNA). The DNA concentration of urine is very low and decreases under most conditions used for sample storage; therefore, the amount of DNA from cryopreserved urine samples may be insufficient for STR analysis. We aimed to establish a multiplexed assay for urine mitochondrial DNA typing containing only trace amounts of DNA, particularly for Japanese populations. A multiplexed suspension-array assay using oligo-tagged microspheres (Luminex MagPlex-TAG) was developed to measure C-stretch length in hypervariable region 1 (HV1) and 2 (HV2), five single nucleotide polymorphisms (SNPs), and one polymorphic indel. Based on these SNPs and the indel, the Japanese population can be classified into five major haplogroups (D4, B, M7a, A, D5). The assay was applied to DNA samples from urine cryopreserved for 1 - 1.5 years (n = 63) and fresh blood (n = 150). The assay with blood DNA enabled Japanese subjects to be categorized into 62 types, exhibiting a discriminatory power of 0.960. The detection limit for cryopreserved urine was 0.005 ng of nDNA. Profiling of blood and urine pairs revealed that 5 of 63 pairs showed different C-stretch patterns in HV1 or HV2. The assay described here yields valuable information in terms of the verification of urine sample sources employing only trace amounts of recovered DNA. However, blood cannot be used as a reference sample.

Characteristics and environmental aspects of slag: a review

USGS Publications Warehouse

Piatak, Nadine M.; Parsons, Michael B.; Seal, Robert R.

2015-01-01

The composition of ferrous slag is dominated by Ca and Si. Steel slag may contain significant Fe, whereas Mg and Al may be significant in Fe slag. Calcium-rich olivine-group silicates, melilite-group silicates that contain Al or Mg, Ca-rich glass, and oxides are the most commonly reported major phases in ferrous slag. Calcite and trace amounts of a variety of sulfides, intermetallic compounds, and pure metals are typically also present. The composition of non-ferrous slag, most commonly from base-metal production, is dominated by Fe and Si with significant but lesser amounts of Al and Ca. Silicates in the olivine, pyroxene, and melilite groups, as well as glass, spinels, and SiO2 (i.e., quartz and other polymorphs) are commonly found in non-ferrous slag. Sulfides and intermetallic compounds are less abundant than the silicates and oxides. The concentrations of some elements exceed generic USEPA soil screening levels for human contact based on multiple exposure pathways; these elements include Al, Cr, Cu, Fe, Mn, Pb, and Zn based on bulk chemical composition. Each slag type usually contains a specific suite of elements that may be of environmental concern. In general, non-ferrous slag may have a higher potential to negatively impact the environment compared to ferrous slag, and is thus a less attractive material for reuse, based on trace element chemistry, principally for base metals. However, the amount of elements released into the environment is not always consistent with bulk chemical composition. Many types of leaching tests have been used to help predict slag’s long-term environmental behavior. Overall, ferrous slags produce an alkaline leachate due to the dissolution of Ca oxides and silicates derived from compounds originally added as fluxing agents, such as lime. Ferrous slag leachate is commonly less metal-rich than leachate from non-ferrous slag generated during base metal extraction; the latter leachate may even be acidic due to the oxidation of sulfides. Because of its characteristics, ferrous slag is commonly used for construction and environmental applications, whereas both non-ferrous and ferrous slag may be reprocessed for secondary metal recovery. Both types of slag have been a source of some environmental contamination. Research into the environmental aspects of slag will continue to be an important topic whether the goal is its reuse, recycling, or remediation.

Solid phase microextraction applied to the analysis of organophosphorus insecticides in fruits.

PubMed

Fytianos, K; Raikos, N; Theodoridis, G; Velinova, Z; Tsoukali, H

2006-12-01

Trace amounts of organophosphorus pesticides (OPs) were determined in various fruits by headspace solid phase microextraction (HS-SPME) and gas chromatography-nitrogen phosphorous detection (GC-NPD). Sampling from the headspace enhanced method selectivity, whereas at the same time improved fiber life time and method sensitivity. Diazinon, parathion, methyl parathion, malathion and fenithrothion were determined in various fruits: more than 150 samples of 21 types of fruits were studied. SPME-GC-NPD provided a useful and very efficient analytical tool: method linearity ranged from 1.2 to 700 ng/ml. Limits of detection (LODs) and quantitation (LOQs) ranged from 0.03 to 3 ng/ml and 0.12 to 10 ng/ml respectively, values well below the residue limits set by the EU. Less than 2% of the samples were found positive containing amounts higher than the EU limits. The effect of fruit peeling and washing was also investigated.

A novel detection approach based on chromophore-decolorizing with free radical and application to photometric determination of copper with acid chrome dark blue.

PubMed

Gao, Hong-Wen; Chen, Fang-Fang; Chen, Ling; Zeng, Teng; Pan, Lu-Ting; Li, Jian-Hua; Luo, Hua-Fei

2007-03-21

A novel detection approach named chromophore-decolorizing with free radicals is developed for determination of trace heavy metal. The hydroxyl radicals (HO) generated from Fe(III) and hydrogen peroxide will oxidize the free chromophore into almost colorless products. The copper-acid chrome dark blue (ACDB) complexation was investigated at pH 5.07. In the presence of Fe(III) and hydrogen peroxide, the excess ACDB was decolorized in the Cu-ACDB reaction solution, and the final solution contained only one color compound, the Cu-ACDB complex. After oxidation of free hydroxyl radicals, the complexation becomes sensitive and selective and it has been used for the quantitation of trace amounts of Cu(II) dissolved in natural water. Beer's law is obeyed in the range from 0 to 0.500 microg mL(-1) Cu(II) and the limit of detection is only 6 microg L(-1) Cu(II). Besides, the Cu-ACDB complex formed was characterized.

Adoption of radio-frequency identification to establish traceability in Taiwanese eel exported to the Japanese market.

PubMed

Jeng, Shu-Ching; Wu, Chun-Lung; Yang, I-Da

2013-01-01

Eel culture and export to the Japanese market is an important industry in Taiwan; however, the average amount produced by each farm is small. Eels from different farms might be mixed before export, making it difficult to determine which farm is responsible for eels containing drug residues. Therefore, the Taiwanese government uses a two-stage procedure of inspection and accreditation for validating the use of good practice in aquaculture farming. Nevertheless, it is still difficult to trace any farm that has produced eels containing drug residues. Radio-frequency identification has the potential to establish traceability in eel products. Here we suggest that Japanese eel importers should insist on the use of radio-frequency identification by Taiwanese eel exporters to enable verification of the safety of eel products being exported to the Japanese market.

Trace Elements and Health

ERIC Educational Resources Information Center

Pettyjohn, Wayne A.

1972-01-01

Summarizes the effects of arsenic, lead, zinc, mercury, and cadmium on human health, indicates the sources of the elements in water, and considers the possibility of students in high schools analyzing water for trace amounts of the elements. (AL)

Inert Reassessment Document for Ethylenediaminetetracetric acid (EDTA)

EPA Pesticide Factsheets

EDTA is a chelating agent. Its ability to bind heavy metal ions can be used to sequester these trace metals. However, trace amounts of various metals are necessary for the proper functioning of the body.

Trace fossils of Marnoso-Arenacea Formation (Miocene), northern Italy: preliminary data

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

McBride, E.F.; Picard, M.D.

Many horizons in the Marnoso-arenacea Formation contain rare to abundant trace fossils at numerous localities. Slope, fan, and basin-plain deposits have trace fossils dominated by the Nereites ichnofacies but include taxa from the Zoophycos ichnofacies plus Ohphiomorpha and Thalassinoides. Slope deposits contain Chondrites, Cosmorhaphe, Desmograpton, Helminthoida, Neonereites, Paleodictyon, Pelecypodichnus, Planolites, Punctorhaphe, and Scolicia; fan-channel deposits contain Chondrites and Planolites; fan-lobe deposits contain Chondrites, Ophiomorpha, Thalassinoides, Scolicia, and Zoophycos; and basin-plain deposits contain Chondrites, Helminthoida, Planolites, and Zoophycos. The distribution of hypichnial taxa may be in part the result of selective preservation (i.e., dependent on the depth of erosion by turbiditymore » currents).« less

Formation of Residual Gases from Source Materials in Closed Crystal Growth Systems

NASA Technical Reports Server (NTRS)

Palosz, W.; Rose, M. Franklin (Technical Monitor)

2001-01-01

Different, non-constituent cases are present in crystal growth systems and may affect processes like growth rate in PVT or voids formation and detached solidification in melt growth systems. The presence of the gas may be detrimental or advantageous depending on its amount and composition, and on the process in question. The presence of the cases, their amount and composition, can be caused and changed by diffusion through and desorption from the growth container material. We have investigated these phenomena for silica glass ampoules. We also found, that residual cases can be generated by the source materials: even very high purity commercial elements and compounds may contain trace amounts of impurities, particularly oxides. The oxides may have low volatilities themselves but their reaction with other species, particularly carbon and hydrogen, may produce volatile compounds like water or carbon oxides. The amount of the gas and its composition is dependent on the original purity of the material (oxide contaminants) and the heat treatment of the source prior to sealing. In many cases. particularly at temperatures below about 900 C and in well-outgassed ampoules, this mechanism dominates. The problem is of a particular importance in sealed systems where the amount and composition of the gas cannot be directly controlled. Therefore, a reasonable knowledge and understanding of the origin, composition, magnitude, and change with time of gases present in sealed ampoules may be important for a meaningful control and interpretation of crystal growth processes. We have investigated this phenomenon in more details for a number of elements and compounds, primarily for II-VI and IV-VI materials. Different source pre-treatment and annealing procedures were applied, and subsequent consecutive annealings and measurements were done to determine the origin and development of the gas in the systems.

Context-sensitive trace inlining for Java.

PubMed

Häubl, Christian; Wimmer, Christian; Mössenböck, Hanspeter

2013-12-01

Method inlining is one of the most important optimizations in method-based just-in-time (JIT) compilers. It widens the compilation scope and therefore allows optimizing multiple methods as a whole, which increases the performance. However, if method inlining is used too frequently, the compilation time increases and too much machine code is generated. This has negative effects on the performance. Trace-based JIT compilers only compile frequently executed paths, so-called traces, instead of whole methods. This may result in faster compilation, less generated machine code, and better optimized machine code. In the previous work, we implemented a trace recording infrastructure and a trace-based compiler for [Formula: see text], by modifying the Java HotSpot VM. Based on this work, we evaluate the effect of trace inlining on the performance and the amount of generated machine code. Trace inlining has several major advantages when compared to method inlining. First, trace inlining is more selective than method inlining, because only frequently executed paths are inlined. Second, the recorded traces may capture information about virtual calls, which simplify inlining. A third advantage is that trace information is context sensitive so that different method parts can be inlined depending on the specific call site. These advantages allow more aggressive inlining while the amount of generated machine code is still reasonable. We evaluate several inlining heuristics on the benchmark suites DaCapo 9.12 Bach, SPECjbb2005, and SPECjvm2008 and show that our trace-based compiler achieves an up to 51% higher peak performance than the method-based Java HotSpot client compiler. Furthermore, we show that the large compilation scope of our trace-based compiler has a positive effect on other compiler optimizations such as constant folding or null check elimination.

Research of stimulants and anabolic steroids in dietary supplements.

PubMed

Baume, N; Mahler, N; Kamber, M; Mangin, P; Saugy, M

2006-02-01

The purpose of this study was to analyze the composition of 103 dietary supplements bought on the internet. The supplements were dispatched in four different categories according to their announced contents [creatine, prohormones, "mental enhancers" and branched chain amino acids (BCAA)]. All the supplements were screened for the presence of stimulants and main anabolic steroids parent compounds. At the same time, the research was focused on the precursors and metabolites of testosterone and nandrolone. The study pointed out three products containing an anabolic steroid, metandienone, in a very high amount. The ingestion of such products induced a high quantity of metandienone metabolites in urines that would be considered as a positive antidoping test. The results have also shown that one creatine product and three "mental enhancers" contained traces of hormones or prohormones not claimed on the labels and 14 prohormone products contained substances other than those indicated by the manufacturer. The oral intake of the creatine product revealed the presence of the two main nandrolone metabolites (19-norandrosterone and 19-noretiocholanolone) in urine.

Performance evaluation of oxygen adsorbents using negative corona discharge-ion mobility spectrometry.

PubMed

Azadkish, Kamal; Jafari, Mohammad T; Ghaziaskar, Hassan S

2017-02-08

Trace amounts of oxygen was determined using negative corona discharge as an ionization source for ion mobility spectrometry. A point-in-cylinder geometry with novel design was used to establish the corona discharge without interferences of negative ions such as NO X - . The desirable background spectrum shows only electrons peak, providing the instrument capable of trace analysis of oxygen in gaseous samples. The limit of detection and linear dynamic range with high coefficient of determination (r 2  = 0.9997), were obtained for oxygen as 8.5 and 28-14204 ppm, respectively. The relative standard deviations of the method for intraday and interday were obtained 4 and 11%, respectively. The satisfactory results revealed the ability of the negative corona discharge ion mobility spectrometry for investigating the performance of synthesized oxygen adsorbents in nitrogen streams. Two oxygen scavengers of MnO and Cu powder were prepared and the optimum temperature of the reactor containing MnO and Cu powder were obtained as 180 and 230 °C, respectively. Due to higher lifetime of copper powder, it was selected as the oxygen scavenger and some parameters such as: the type of adsorbent support, the size of adsorbent particles, and the amount of copper were studied for preparation of more efficient oxygen adsorbent. Copyright © 2016 Elsevier B.V. All rights reserved.

The geochemistry of environmentally important trace elements in UK coals, with special reference to the Parkgate coal in the Yorkshire-Nottinghamshire Coalfield, UK

USGS Publications Warehouse

Spears, D.A.; Tewalt, S.J.

2009-01-01

The Parkgate coal of Langsettian age in the Yorkshire-Nottinghamshire coalfield is typical of many coals in the UK in that it has a high sulphur (S) content. Detailed information on the distribution of the forms of S, both laterally and vertically through the seam, was known from previous investigations. In the present work, 38 interval samples from five measured sections of the coal were comprehensively analysed for major, minor and trace elements and the significance of the relationships established using both raw and centered log transformed data. The major elements are used to quantify the variations in the inorganic and organic coal components and determine the trace element associations. Pyrite contains nearly all of the Hg, As, Se, Tl and Pb and is also the major source of the Mo, Ni, Cd and Sb. The clays contain the following elements in decreasing order of association: Rb, Cs, Li, Ga, U, Cr, V, Sc, Y, Bi, Cu, Nb, Sn, Te and Th. Nearly all of the Rb is present in the clay fraction, whereas for elements such as V, Cu and U, a significant amount is thought to be present in the organic matter, based on the K vs trace element regression equations. Only Ge, and possibly Be, would appear to have a dominant organic source. The trace element concentrations are calculated for pyrite, the clay fraction and organic matter. For pyrite it is noted that concentrations agree with published data from the Yorkshire-Nottinghamshire coalfield and also that Tl concentrations (median of 0.33 ppm) in the pyrite are greater than either Hg or Cd. Unlike these elements, Tl has attracted less attention and possibly more information is needed on its anthropogenic distribution and impacts on man and the environment. A seawater source is thought to be responsible for the high concentrations of S, Cl and the non-detrital trace elements in the Parkgate coal. Indicative of the seawater control is the Th/U ratio, which expresses the detrital to non-detrital element contributions. Using other elements, similar ratios can be calculated, which in combination offer greater interpretative value. ?? 2009 Elsevier B.V.

Determination of the Tribological Fundamentals of Solid Lubricated Ceramics. Volume 3. Appendices P through II

DTIC Science & Technology

1991-09-01

9H and tungsten silicides may also be present in the microstructure. The non-SiC eiemental concentrations for NC-203 would not be expected to exceed...lesser amounts of yttrium silicate and tungsten silicide . Trace amounts of a-Si 3N4 , silicon oxynitride, tungsten-iron- silicide , and yttrium silicon...SiC ESK On this sample, we detect Silicon, Carbon, and also Oxygen and Nitrogen, as well as Calcium and Sodium traces. After ionic etching up to about

Amino acid, mineral and fatty acid content of pumpkin seeds (Cucurbita spp) and Cyperus esculentus nuts in the Republic of Niger.

PubMed

Glew, R H; Glew, R S; Chuang, L-T; Huang, Y-S; Millson, M; Constans, D; Vanderjagt, D J

2006-06-01

Dried seeds and nuts are widely consumed by indigenous populations of the western Sahel, especially those who inhabit rural areas. In light of the need for quantitative information regarding the content of particular nutrients in these plant foods, we collected dried pumpkin (Cucurbita spp) seeds and nuts of Cyperus esculentus in the Republic of Niger and analyzed them for their content of essential amino acids, minerals and trace elements, and fatty acids. On a dry weight basis, pumpkin seed contained 58.8% protein and 29.8% fat. However, the lysine score of the protein was only 65% relative to the FAO/WHO protein standard. The pumpkin seed contained useful amounts of linoleic (92 microg/g dry weight) and the following elements (on a microg per g dry weight basis): potassium (5,790), magnesium (5,690), manganese (49.3), zinc (113), selenium (1.29), copper (15.4), chromium (2.84), and molybdenum (0.81), but low amounts of calcium and iron. Except for potassium (5,573 microg/g dry weight) and chromium (2.88 microg/g dry weight), the C. esculentis nuts contained much less of these same nutrients compared to pumpkin seeds. In conclusion, pumpkin seeds represent a useful source of many nutrients essential to humans. The data in this report should of practical value to public health officials in rural areas of sub-Saharan Africa.

Effect of Rare Earth Ions on the Properties of Composites Composed of Ethylene Vinyl Acetate Copolymer and Layered Double Hydroxides

PubMed Central

Wang, Lili; Li, Bin; Zhao, Xiaohong; Chen, Chunxia; Cao, Jingjing

2012-01-01

Background The study on the rare earth (RE)-doped layered double hydroxides (LDHs) has received considerable attention due to their potential applications in catalysts. However, the use of RE-doped LDHs as polymer halogen-free flame retardants was seldom investigated. Furthermore, the effect of rare earth elements on the hydrophobicity of LDHs materials and the compatibility of LDHs/polymer composite has seldom been reported. Methodology/Principal Findings The stearate sodium surface modified Ni-containing LDHs and RE-doped Ni-containing LDHs were rapidly synthesized by a coprecipitation method coupled with the microwave hydrothermal treatment. The influences of trace amounts of rare earth ions La, Ce and Nd on the amount of water molecules, the crystallinity, the morphology, the hydrophobicity of modified Ni-containing LDHs and the adsorption of modifier in the surface of LDHs were investigated by TGA, XRD, TEM, contact angle and IR, respectively. Moreover, the effects of the rare earth ions on the interfacial compatibility, the flame retardancy and the mechanical properties of ethylene vinyl acetate copolymer (EVA)/LDHs composites were also explored in detail. Conclusions/Significance S-Ni0.1MgAl-La displayed more uniform dispersion and better interfacial compatibility in EVA matrix compared with other LDHs. Furthermore, the S-Ni0.1MgAl-La/EVA composite showed the best fire retardancy and mechanical properties in all composites. PMID:22693627

Characterisation of mineralogical forms of barium and trace heavy metal impurities in commercial barytes by EPMA, XRD and ICP-MS.

PubMed

Ansari, T M; Marr, I L; Coats, A M

2001-02-01

This study was carried out to characterise the mineralogical forms of barium and the trace heavy metal impurities in commercial barytes of different origins using electron probe microanalysis (EPMA), X-ray diffraction (XRD) and inductively coupled plasma mass spectrometry (ICP-MS). Qualitative EPMA results show the presence of typically eight different minerals in commercial barytes including barite (BaSO4), barium feldspar, galena (PbS), pyrite (FeS2), sphalerite (ZnS), quartz (SiO2), and silicates, etc. Quantitative EPMA confirms that the barite crystals in the barytes contain some strontium and a little calcium, whereas trace heavy metals occur in the associated minerals. Analysis of aqua regia extracts of barytes samples by ICP-MS has shown the presence of a large number of elements in the associated minerals. Arsenic, copper and zinc concentrations correlate closely in all 10 samples. The findings suggest that barytes is not, as traditionally thought, an inert mineral, but is a potentially toxic substance due to its associated heavy metal impurities, which can be determined by an aqua regia digest without the need for complete dissolution of the barite itself. X-ray powder diffraction was not informative as the complex barite pattern masks the very weak lines from the small amounts of associated minerals.

Trace element contaminants in mineral fertilizers used in Iran.

PubMed

Latifi, Zahra; Jalali, Mohsen

2018-05-25

The application of mineral fertilizers which have contaminants of trace elements may impose concern regarding the entry and toxic accumulation of these elements in agro-ecosystems. In this study, 57 mineral fertilizers (nitrogen, potassium, phosphate, and compound fertilizers) distributed in Iran were analyzed for their contents of Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn, and Fe. The results revealed that the contents of these trace elements varied considerably depending on the type of the element and the fertilizer. Among these elements, Fe displayed the highest average content, whereas Cd showed the lowest. Generally, the trace element contents in P-containing fertilizers were higher than those in nitrogen and potassium fertilizers. The mean values of trace elements (mg kg -1 ) in P-containing fertilizers were 4.0 (Cd), 5.5 (Co), 35.7 (Cr), 24.4 (Cu), 272 (Mn), 14.3 (Ni), 6.0 (Pb), 226 (Zn), and 2532 (Fe). Comparing trace element contents to limit values set by the German Fertilizer Ordinance showed that the mean contents of potentially toxic trace elements, such as Cd and Pb, were lower than their limit values in all groups of fertilizers. On the other hand, while a number of fertilizers contained a high content of some essential trace elements, particularly Fe, they were not labeled as such.

The Origin of Life in a Terrestrial Hydrothermal Pool? The Importance of a Catalytic Surface

NASA Astrophysics Data System (ADS)

Sydow, L. A.; Bennett, P.

2013-12-01

A premise of one chemoautotrophic theory for the origin of life is that a recurring reaction catalyzed on the charged surfaces of pyrite served as the first metabolism and was later enveloped by a primitive cellular membrane. This proposed 'surface metabolism' is analogous to the reductive acetyl-CoA pathway (Wächtershäuser 1988) and requires the abiotic formation of methanethiol (CH3SH), the simplest of the alkyl thiols, which would serve the role of coenzyme-A in the surface metabolism. Abiogenic CH3SH has not previously been identified in terrestrial hot springs, but it has been produced in the laboratory under hydrothermal conditions in the presence of a catalyst, usually FeS. Its formation would occur via the following reactions, with reaction 2 requiring catalysis: CO2 + 2H2S --> CS2 + 2H2O (1) CS2 + 3H2 --> CH3SH + H2S (2) We have identified CH3SH in Cinder Pool, an acid-sulfate-chloride hot spring in Yellowstone National Park. This spring is unusual in that it contains a subaqueous molten sulfur layer (~18 m depth) and thousands of iron-sulfur-spherules floating on the surface, which are created by gas bubbling through the molten floor of the spring. Analysis with EDS has shown that cinder material, largely composed of elemental sulfur, also contains trace iron sulfide minerals, meaning it could serve as a reactive and catalytic surface for abiogenic CH3SH formation in Cinder Pool. Furthermore, the cinders themselves are highly porous, and these void spaces could trap necessary reactants near the catalytic surface. Gas samples were collected from Cinder pool in fall of 2011 using the bubble strip method. One sample contained measurable quantities of CH3SH, and all samples contained related reactant sulfur gases such as large amounts of H2S, and smaller amounts of CS2 and dimethyl disulfide. Laboratory microcosm experiments were conducted to replicate these findings in a sterile environment to ensure CH3SH generation was abiotic. Analog Cinder Pool water and either FeS, FeS2, or cinders collected from the pool itself were incubated with H2, CO2, and CS2 as reaction gases for over a week at pool temperatures. An experiment was also conducted without CS2 to see if the solid materials could act as the sole source of sulfur. All of the experimental solids were capable of catalyzing CH3SH production when CS2 was added. Without added CS2, however, only cinders produced CH3SH, while FeS and FeS2 bottles could only make small amounts of H2S. Presumably, the large amount of elemental sulfur in the cinders creates enough H2S for the subsequent generation of CS2 then CH3SH, which is catalyzed by the trace iron-sulfide they also contain. Cinders act as an excellent reaction surface for CH3SH generation, and a similar material may have played a significant part in the advent of life on earth.

Detection of titanium in human tissues after craniofacial surgery.

PubMed

Jorgenson, D S; Mayer, M H; Ellenbogen, R G; Centeno, J A; Johnson, F B; Mullick, F G; Manson, P N

1997-04-01

Generally, titanium fixation plates are not removed after osteosynthesis, because they have high biocompatability and high corrosion resistance characteristics. Experiments with laboratory animals, and limited studies of analyses of human tissues, have reported evidence of titanium release into local and distant tissues. This study summarizes our results of the analysis of soft tissues for titanium in four patients with titanium microfixation plates. Energy dispersive x-ray analysis, scanning electron microscopy, and electrothermal atomic absorption spectrophotometry were used to detect trace amounts of titanium in surrounding soft tissues. A single metal inclusion was detected by scanning electron microscopy and energy dispersive x-ray analysis in one patient, whereas, electrothermal atomic absorption spectrophotometry analyses revealed titanium present in three of four specimens in levels ranging from 7.92 to 31.8 micrograms/gm of dry tissue. Results from this study revealed trace amounts of titanium in tissues surrounding craniofacial plates. At the atomic level, electrothermal atomic absorption spectrophotometry appears to be a sensitive tool to quantitatively detect ultra-trace amounts of metal in human tissue.

In vitro study of role of trace amount of Cu release from Cu-bearing stainless steel targeting for reduction of in-stent restenosis.

PubMed

Ren, Ling; Xu, Lu; Feng, Jingwen; Zhang, Yang; Yang, Ke

2012-05-01

A novel 316L type Cu-bearing stainless steel was developed in present work, aiming at reducing the occurrence of the in-stent restenosis after implantations of coronary stents, through trace amount of Cu release from surface of the steel in body fluid. It was found that there was a trace amount of Cu released from the Cu-bearing steel in a simulated body fluid, with no cytotoxicity. All the in vitro experimental results proved that this Cu-bearing steel could not only inhibit the proliferation of vascular smooth muscle cells, reducing the formation of thrombosis, which are the main reasons for happening of the in-stent restenosis, but also promote the proliferation of vascular endothelial cells needed for the revascularization, showing that this novel steel is prospective to be a new material for manufacturing coronary stents with function of reducing the in-stent restenosis.

Extraction of trace metals from fly ash

DOEpatents

Blander, M.; Wai, C.M.; Nagy, Z.

1983-08-15

A process is described for recovering silver, gallium and/or other trace metals from a fine grained industrial fly ash associated with a process for producing phosphorous. The fly ash has a silicate base and contains surface deposits of the trace metals as oxides, chlorides or the like. The process is carried out by contacting the fly ash with AlCl/sub 3/ in an alkali halide melt to react the trace metals with the AlCl/sub 3/ to form compositions soluble in the melt and a residue containing the silicate and aluminum oxide or other aluminum precipitate, and separating the desired trace metal or metals from the melt by electrolysis or other separation techniques.

Extraction of trace metals from fly ash

DOEpatents

Blander, Milton; Wai, Chien M.; Nagy, Zoltan

1984-01-01

A process for recovering silver, gallium and/or other trace metals from a fine grained industrial fly ash associated with a process for producing phosphorous, the fly ash having a silicate base and containing surface deposits of the trace metals as oxides, chlorides or the like, with the process being carried out by contacting the fly ash with AlCl.sub.3 in an alkali halide melt to react the trace metals with the AlCl.sub.3 to form compositions soluble in the melt and a residue containing the silicate and aluminum oxide or other aluminum precipitate, and separating the desired trace metal or metals from the melt by electrolysis or other separation techniques.

The occurrence of paralytic shellfish toxins in two species of xanthid crab from Suva barrier reef, Fiji Islands.

PubMed

Raj, U; Haq, H; Oshima, Y; Yasumoto, T

1983-01-01

Five species of crabs commonly occurring on Suva barrier reef, Fiji Islands, were tested for the presence of paralytic shellfish toxins. All 35 specimens of Atergatis floridus and all 18 specimens of Zosimus aeneus tested were lethal to mice, whilst none of 12 specimens of Carpilius maculatus, 8 of C. convexus and 10 of Eriphia sebana tested were lethal. A. floridus contained saxitoxin (55--60%), neosaxitoxin (35--40%), gonyautoxin-II (less than 5%) and a new toxin previously found in a toxic dinoflagellate, Pyrodinium bahamense var. compressa, and tentatively coded PBT (1%). Z. aeneus contained the same components, with additional trace amounts of gonyautoxin-I and III, but neosaxitoxin was the major component in this species. Comparison with the results of testing Okinawan specimens of Z. aeneus, A. floridus and Platipodia granulosa suggests that the toxin profile is specific to species.

Intensity of quartz cathodoluminescence and trace-element content in quartz from the porphyry copper deposit at Butte, Montana

USGS Publications Warehouse

Rusk, B.G.; Reed, M.H.; Dilles, J.H.; Kent, A.J.R.

2006-01-01

Textures of hydrothermal quartz revealed by cathodoluminescence using a scanning electron microscope (SEM-CL) reflect the physical and chemical environment of quartz formation. Variations in intensity of SEM-CL can be used to distinguish among quartz from superimposed mineralization events in a single vein. In this study, we present a technique to quantify the cathodoluminescent intensity of quartz within individual and among multiple samples to relate luminescence intensity to specific mineralizing events. This technique has been applied to plutonic quartz and three generations of hydrothermal veins at the porphyry copper deposit in Butte, Montana. Analyzed veins include early quartz-molybdenite veins with potassic alteration, pyrite-quartz veins with sericitic alteration, and Main Stage veins with intense sericitic alteration. CL intensity of quartz is diagnostic of each mineralizing event and can be used to fingerprint quartz and its fluid inclusions, isotopes, trace elements, etc., from specific mineralizing episodes. Furthermore, CL intensity increases proportional to temperature of quartz formation, such that plutonic quartz from the Butte quartz monzonite (BQM) that crystallized at temperatures near 750 ??C luminesces with the highest intensity, whereas quartz that precipitated at ???250 ??C in Main Stage veins luminesces with the least intensity. Trace-element analyses via electron microprobe and laser ablation-ICP-MS indicate that plutonic quartz and each generation of hydrothermal quartz from Butte is dominated by characteristic trace amounts of Al, P, Ti, and Fe. Thus, in addition to CL intensity, each generation of quartz can be distinguished based on its unique trace-element content. Aluminum is generally the most abundant element in all generations of quartz, typically between 50 and 200 ppm, but low-temperature, Main Stage quartz containing 400 to 3600 ppm Al is enriched by an order of magnitude relative to all other quartz generations. Phosphorous is present in abundances between 25 and 75 ppm, and P concentrations in quartz show little variation among quartz generations. Iron is the least abundant of these elements in most quartz types and is slightly enriched in CL-dark quartz in pyrite-quartz veins with sericitic alteration. Titanium is directly correlated with both temperature of quartz precipitation, and intensity of quartz luminescence, such that BQM quartz contains hundreds of ppm Ti, whereas Main Stage quartz contains less than 10 ppm Ti. Our results suggest that Ti concentration in quartz is controlled by temperature of quartz precipitation and that increased Ti concentrations in quartz may be responsible for increased CL intensities.

Determination of trace elements of Egyptian cane sugar (Naga Hammady factories) by neutron activation, atomic absorption spectrophotometric and inductively coupled plasma-atomic emission spectrometric analyses.

PubMed

Awadallah, R M; Sherif, M K; Mohamed, A E; Grass, F

1984-01-01

INAA, AAS and ICP-AES techniques are applied to the determination of trace amounts of Ag, Al, As, Au, Ba, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Dy, Eu, Fe, Ga, Hf, K, La, Li, Lu, Mg, Mn, Na, Nb, Ni, Pb, Sb, Sc, Se, Sm, Sn, Sr, Ta, Th, Ti, U, V, W and Zn in the stalks of sugar cane plant after extracting juice, raw juice principal (mixed) juice, juice withdrawn from the successive stages of sugar industry, sirup, deposits from evaporators, molasse, A-? and B-sugar and in the soil samples (collected from the field supplying the factories by cane plants) taken from the immediate vicinity of the plant roots at surface, 30 and 60 cm depth. The results obtained are in a good agreement of the safety baselines of using juice as beverage, molasse derivatives (honey, sweets, ...) as diet for common people in the developed countries and in industry (methanol, ethanol, acetone & acetic acid, ...) and sugar sweeting for many purposes (in beverages, desserts, ...). Differences of trace elements concentrations in soil samples may be reasoned to geochemical and biogeochemical fractionation while those in juice may be due to the changes in the environmental conditions, chemical composition and botanic structures. Variations in trace element contents in the products formed during the successive stages of sugar industry may be a result of evaporation, filtration processes, chemical treatments or corrosion of vessels, containers or engines. Trace elements are very important where they are responsible for enzymatic and biochemical reactions, matabolism, health and diseases.

Iron active electrode and method of making same

DOEpatents

Jackovitz, John F.; Seidel, Joseph; Pantier, Earl A.

1982-10-26

An iron active electrode and method of preparing same in which iron sulfate is calcined in an oxidizing atmosphere at a temperature in the range of from about 600.degree. C. to about 850.degree. C. for a time sufficient to produce an iron oxide with a trace amount of sulfate. The calcined material is loaded into an electrically conductive support and then heated in a reducing atmosphere at an elevated temperature to produce activated iron having a trace amount of sulfide which is formed into an electrode plate.

Trace determination of zinc by substoichiometric isotope dilution analysis

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

Sandhya, D.; Priya, S.; Subramanian, M.O.S.

1996-09-01

A radiometric method based on substoichiometric isotope dilution analysis using 1,10-phenanthroline and a substoichiometric amount of eosin was developed for determining trace amounts of zinc. Evaluation of various metal ion interferences shows that as little as 0.2 {mu}g Zn could be determined in an aqueous-phase volume of 60 mL. The method has been successfully applied to the determination of Zn in city waste incineration ash, cadmium metal, Fourts-B tablets, Boro-plus ointment, and magnesium alloy samples. 12 refs., 3 figs., 3 tabs.

Radiochemical separation of gallium by amalgam exchange

USGS Publications Warehouse

Ruch, R.R.

1969-01-01

An amalgam-exchange separation of radioactive gallium from a number of interfering radioisotopes has been developed. A dilute (ca. 0.3%) gallium amalgam is agitated with a slightly acidic solution of 72Ga3+ containing concentrations of sodium thiocyanate and either perchlorate or chloride. The amalgam is then removed and the radioactive gallium stripped by agitation with dilute nitric acid. The combined exchange yield of the perchlorate-thiocyanate system is 90??4% and that of the chloride-thiocyanate system is 75??4%. Decontamination yields of most of the 11 interfering isotopes studied were less than 0.02%. The technique is applicable for use with activation analysis for the determination of trace amounts of gallium. ?? 1969.

The use of hydroxyacids as geochemical indicators

NASA Technical Reports Server (NTRS)

Cardoso, J. N.; Eglinton, G.

1983-01-01

The distributions of hydroxyacids in a variety of recent and ancient sediments have been determined by gas chromatography-mass spectrometry. A lacustrine sediment (Rostherne Mere, U.K.) and two marine situations (Cariaco Trench, Black Sea) were analyzed as examples of recent depositional environments. Beta-hydroxyacids occurred in all of the recent sediments, consistent with their presumed microbial origin, whereas di- and trihydroxyacids were present in the sediments with a significant higher plant input (Black Sea and Rostherne Mere sediments). The two ancient (Eocene) sediments examined, viz, the Greene River (U.S.) and Messel (Germany) oil shales, contained only trace amounts of hydroxyacids. These results provide evidence that hydroxyacids are in general not well preserved over geological time.

Indirect spectrophotometric determination of traces of bromide in water

USGS Publications Warehouse

Fishman, M. J.; Skougstad, M.W.

1963-01-01

A rapid, accurate, and sensitive indirect spectrophotometric method for the determination of bromide in natural waters is based on the catalytic effect of bromide on the oxidation of iodine to iodate by potassium permanganate in sulfuric acid solution. The method is applicable to concentrations ranging from 1 to 100 ??g. of bromide per liter, but may be modified to extend the concentration range. Most ions commonly occurring in water do not interfere. The standard deviation is 2.9 at bromide concentrations of 100 ??g. per liter and less at lower concentrations. The determination of bromide in samples containing known added amounts gave values ranging from 99 to 105% of the concentration calculated to be present.

[The concept of the development of the state of chemical-analytical environmental monitoring].

PubMed

Rakhmanin, Iu A; Malysheva, A G

2013-01-01

Chemical and analytical monitoring of the quality of environment is based on the accounting of the trace amount of substances. Considering the multicomponent composition of the environment and running processes of transformation of substances in it, in determination of the danger of the exposure to the chemical pollution of environment on population health there is necessary evaluation based on the simultaneous account of complex of substances really contained in the environment and supplying from different sources. Therefore, in the analytical monitoring of the quality and safety of the environment there is a necessary conversion from the orientation, based on the investigation of specific target substances, to estimation of real complex of compounds.

Production of sintered porous metal fluoride pellets

DOEpatents

Anderson, L.W.; Stephenson, M.J.

1973-12-25

Porous pellets characterized by a moderately reactive crust and a softer core of higher reactivity are produced by forming agglomerates containing a metal fluoride powder and a selected amount ofwater. The metal fluoride is selected to be sinterable and essentially non-reactive with gaseous fluorinating agents. The agglomerates are contacted with a gaseous fluorinating agent under controlled conditions whereby the heat generated by localized reaction of the agent and water is limited to values effccting bonding by localized sintering. Porous pellets composed of cryolite (Na/sub 3/AlF/sub 6/) can be used to selectively remove trace quantities of niobium pentafluoride from a feed gas consisting predominantly of uranium hexafluoride. (Official Gazette)

Copper modified carbon molecular sieves for selective oxygen removal

NASA Technical Reports Server (NTRS)

Sharma, Pramod K. (Inventor); Seshan, Panchalam K. (Inventor)

1992-01-01

Carbon molecular sieves modified by the incorporation of finely divided elemental copper useful for the selective sorption of oxygen at elevated temperatures. The carbon molecular sieves can be regenerated by reduction with hydrogen. The copper modified carbon molecular sieves are prepared by pyrolysis of a mixture of a copper-containing material and polyfunctional alcohol to form a sorbent precursor. The sorbent precursors are then heated and reduced to produce copper modified carbon molecular sieves. The copper modified carbon molecular sieves are useful for sorption of all concentrations of oxygen at temperatures up to about 200.degree. C. They are also useful for removal of trace amount of oxygen from gases at temperatures up to about 600.degree. C.

Estimation of trace amounts of benzene in solvent-extracted vegetable oils and oil seed cakes.

PubMed

Masohan, A; Parsad, G; Khanna, M K; Chopra, S K; Rawat, B S; Garg, M O

2000-09-01

A new method is presented for the qualitative and quantitative estimation of trace amounts (up to 0.15 ppm) of benzene in crude as well as refined vegetable oils obtained by extraction with food grade hexane (FGH), and in the oil seed cakes left after extraction. The method involves the selection of two solvents; cyclohexanol, for thinning of viscous vegetable oil, and heptane, for azeotroping out trace benzene as a concentrate from the resulting mixture. Benzene is then estimated in the resulting azeotrope either by UV spectroscopy or by GC-MS subject to availability and cost effectiveness of the latter. Repeatability and reproducibility of the method is within 1-3% error. This method is suitable for estimating benzene in vegetable oils and oil seed cakes.

High throughput liquid absorption preconcentrator sampling instrument

DOEpatents

Zaromb, Solomon; Bozen, Ralph M.

1992-01-01

A system for detecting trace concentrations of an analyte in air includes a preconcentrator for the analyte and an analyte detector. The preconcentrator includes an elongated tubular container comprising a wettable material. The wettable material is continuously wetted with an analyte-sorbing liquid which flows from one part of the container to a lower end. Sampled air flows through the container in contact with the wetted material with a swirling motion which results in efficient transfer of analyte vapors or aerosol particles to the sorbing liquid and preconcentration of traces of analyte in the liquid. The preconcentrated traces of analyte may be either detected within the container or removed therefrom for injection into a separate detection means or for subsequent analysis.

High-throughput liquid-absorption preconcentrator sampling methods

DOEpatents

Zaromb, Solomon

1994-01-01

A system for detecting trace concentrations of an analyte in air includes a preconcentrator for the analyte and an analyte detector. The preconcentrator includes an elongated tubular container comprising a wettable material. The wettable material is continuously wetted with an analyte-sorbing liquid which flows from one part of the container to a lower end. Sampled air flows through the container in contact with the wetted material with a swirling motion which results in efficient transfer of analyte vapors or aerosol particles to the sorbing liquid and preconcentration of traces of analyte in the liquid. The preconcentrated traces of analyte may be either detected within the container or removed therefrom for injection into a separate detection means or for subsequent analysis.

High throughput liquid absorption preconcentrator sampling instrument

DOEpatents

Zaromb, S.; Bozen, R.M.

1992-12-22

A system for detecting trace concentrations of an analyte in air includes a preconcentrator for the analyte and an analyte detector. The preconcentrator includes an elongated tubular container comprising a wettable material. The wettable material is continuously wetted with an analyte-sorbing liquid which flows from one part of the container to a lower end. Sampled air flows through the container in contact with the wetted material with a swirling motion which results in efficient transfer of analyte vapors or aerosol particles to the sorbing liquid and preconcentration of traces of analyte in the liquid. The preconcentrated traces of analyte may be either detected within the container or removed therefrom for injection into a separate detection means or for subsequent analysis. 12 figs.

High-throughput liquid-absorption preconcentrator sampling methods

DOEpatents

Zaromb, S.

1994-07-12

A system for detecting trace concentrations of an analyte in air includes a preconcentrator for the analyte and an analyte detector. The preconcentrator includes an elongated tubular container comprising a wettable material. The wettable material is continuously wetted with an analyte-sorbing liquid which flows from one part of the container to a lower end. Sampled air flows through the container in contact with the wetted material with a swirling motion which results in efficient transfer of analyte vapors or aerosol particles to the sorbing liquid and preconcentration of traces of analyte in the liquid. The preconcentrated traces of analyte may be either detected within the container or removed therefrom for injection into a separate detection means or for subsequent analysis. 12 figs.

Electronic and steric influences of pendant amine groups on the protonation of molybdenum bis (dinitrogen) complexes

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

Labios, Liezel A.; Heiden, Zachariah M.; Mock, Michael T.

2015-05-04

The synthesis of a series of P EtP NRR' (P EtP NRR' = Et₂PCH₂CH₂P(CH₂NRR')₂, R = H, R' = Ph or 2,4-difluorophenyl; R = R' = Ph or iPr) diphosphine ligands containing mono- and disubstituted pendant amine groups, and the preparation of their corresponding molybdenum bis(dinitrogen) complexes trans-Mo(N₂)₂(PMePh₂)₂(P EtP NRR') is described. In situ IR and multinuclear NMR spectroscopic studies monitoring the stepwise addition of (HOTf) to trans-Mo(N₂)₂(PMePh₂)₂(P EtP NRR') complexes in THF at -40 °C show that the electronic and steric properties of the R and R' groups of the pendant amines influence whether the complexes are protonated atmore » Mo, a pendant amine, a coordinated N2 ligand, or a combination of these sites. For example, complexes containing mono-aryl substituted pendant amines are protonated at Mo and pendant amine to generate mono- and dicationic Mo–H species. Protonation of the complex containing less basic diphenyl-substituted pendant amines exclusively generates a monocationic hydrazido (Mo(NNH₂)) product, indicating preferential protonation of an N₂ ligand. Addition of HOTf to the complex featuring more basic diisopropyl amines primarily produces a monocationic product protonated at a pendant amine site, as well as a trace amount of dicationic Mo(NNH₂) product that contain protonated pendant amines. In addition, trans-Mo(N₂)₂(PMePh₂)₂(depe) (depe = Et₂PCH₂CH₂PEt₂) without a pendant amine was synthesized and treated with HOTf, generating a monocationic Mo(NNH₂) product. Protonolysis experiments conducted on select complexes in the series afforded trace amounts of NH₄⁺. Computational analysis of the series of trans-Mo(N₂)₂(PMePh₂)₂(P EtP NRR') complexes provides further insight into the proton affinity values of the metal center, N₂ ligand, and pendant amine sites to rationalize the differing reactivity profiles. This research was supported as part of the Center for Molecular Electrocatalysis, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences. Computational resources provided by the National Energy Research Scientific Computing Center (NERSC) at Lawrence Berkeley National Laboratory. Pacific Northwest National Laboratory is operated by Battelle for the U.S. Department of Energy.« less

Characterisation of FOGs in grease trap waste from the processing of chickens in Thailand.

PubMed

Nitayapat, Nuttakan; Chitprasert, Pakamon

2014-06-01

Industrial firms that kill and process chickens generate wastewater that contains fat, oil, and grease (FOG). The FOGs are located in the fatty waste that is collected by floatation in grease traps. Chemical and physical characterisation of FOGs would provide useful information that would help in the development of methods designed to decrease the extent of pollution caused by disposal of the waste and to utilise commercially some of its lipid constituents. Employing these methods would enhance the profitability and competitive potential of these commercial organisations. Samples of grease trap waste from 14 firms in central Thailand have been examined. Due to the very different schemes of waste management employed by these firms, the physical appearance of their fatty wastes showed considerable variation. The chemical and physical properties of the FOGs present in these wastes showed considerable variation also. Large amounts of free fatty acids (10-70% as oleic acid) were detected in most of the 14 wastes and palmitic, cis-9-oleic, cis,cis-9,12-linoleic, stearic, and palmitoleic acids were the predominant species of free and esterified acids. Most of the FOGs were solid at temperatures below 40 °C. Many of them contained traces of heavy metals (Cu and Pb) and some contained traces of the pesticides dimethoate and cypermethrin. The content of these potentially hazardous substances would have to be considered very carefully before discarding the fatty wastes and during the development of methods designed to isolate their potentially profitable lipid constituents. Copyright © 2013 Elsevier Ltd. All rights reserved.

Method for remote detection of trace contaminants

DOEpatents

Simonson, Robert J.; Hance, Bradley G.

2003-09-09

A method for remote detection of trace contaminants in a target area comprises applying sensor particles that preconcentrate the trace contaminant to the target area and detecting the contaminant-sensitive fluorescence from the sensor particles. The sensor particles can have contaminant-sensitive and contaminant-insensitive fluorescent compounds to enable the determination of the amount of trace contaminant present in the target are by relative comparison of the emission of the fluorescent compounds by a local or remote fluorescence detector. The method can be used to remotely detect buried minefields.

The deposition and fate of trace metals in our environment.

Treesearch

Elon S. Verry; Stephen J. Vermette

1992-01-01

This proceedings contains 14 invited papers from Canada and the United States on trace metal emissions, trace metal measurement in precipitation and dry fall, regional deposition, and the fate of trace metals in soils, plants, waters, and fish. A summary paper integrates the major findings of each paper.

Solvent cleaning of pole transformers containing PCB contaminated insulating oil.

PubMed

Kanbe, H; Shibuya, M

2001-01-01

In 1989, it was discovered that the recycled insulation oil in pole transformers for electric power supply was contaminated with trace amounts of polychlorinated biphenyls (PCBs; maximum 50 mg-PCB/kg-insulation oil). In order to remove the PCBs from transformer components using n-hexane as a solvent, we investigated the relationship between progressive stages of dismantling and cleaning results. The results are summarized as follows: (1) Based on the cleaning test results, we made an estimate of the residual PCB amount on iron and copper components. By dismantling the test pole transformers into the "iron core and coil portion" and cleaning the components, we achieved a residual PCB amount that was below the limit of detection (0.05 mg-PCB/kg-material). To achieve a residual PCB amount below the limit of detection for the transformer paper component, it was necessary to cut the paper into pieces smaller than 5 mm. We were unable to achieve a residual PCB amount below the limit of detection for the wood component. (2) Compared to Japan's stipulated limited concentration standard values for PCBs, the results of the cleaning test show that cleaning iron or copper components with PCBs only on their surface with the solvent n-hexane will satisfy the limited concentration standard values when care is taken to ensure the component surfaces have adequate contact with the cleaning solvent.

Transformations of inorganic mercury by Candida albicans and Saccharomyces cerevisiae

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

Yannai, S.; Berdicevsky, I.; Duek, L.

1991-01-01

Saccharomyces cerevisiae and Candida albicans were incubated with 0.25, 0.5, or 0.75 {mu}g of Hg (as HgCl{sub 2}) per ml of Nelson's medium in the presence of trace amounts of oxygen at 28{degree}C for 12 days. Two control media were used, one without added Hg and one without yeast inoculum. Yeast cell growth was estimated after 1, 2, 3, and 8 days of incubation. The contents of organomercury in the system and of elemental mercury released from the media and collected in traps were determined at the end of the experiments. The results were as follows: (1) C. albicans wasmore » the more mercury-resistant species, but both yeast species failed to grown in the media containing 0.75 {mu}g of Hg per ml.; (2) The amounts of organomercury produced by the two species were proportional to the amount of HgCl{sub 2} added to the medium. In all cases C. albicans produced considerably larger amounts of methylmercury than S. cerevisiae; (3) The amounts of elemental Hg produced were inversely proportional to the HgCl{sub 2} level added in the case of S. cerevisiae but were all similar in the case of C. albicans;and (4) Neither organomercury nor elemental Hg was produced in any of the control media.« less

Characterization of Two Campylobacter jejuni Strains for Use in Volunteer Experimental-Infection Studies▿ †

PubMed Central

Poly, Frédéric; Read, Timothy D.; Chen, Yu-Han; Monteiro, Mario A.; Serichantalergs, Oralak; Pootong, Piyarat; Bodhidatta, Ladaporn; Mason, Carl J.; Rockabrand, David; Baqar, Shahida; Porter, Chad K.; Tribble, David; Darsley, Michael; Guerry, Patricia

2008-01-01

The development of vaccines against Campylobacter jejuni would be facilitated by the ability to perform phase II challenge studies. However, molecular mimicry of the lipooligosaccharide (LOS) of most C. jejuni strains with human gangliosides presents safety concerns about the development of Guillain-Barré syndrome. Clinical isolates of C. jejuni that appeared to lack genes for the synthesis of ganglioside mimics were identified by DNA probe analyses. Two clinical isolates from Southeast Asia (strains BH-01-0142 and CG8421) were determined to express the LOS type containing N-acetyl quinovosamine. No ganglioside structures were observed to be present in the LOSs of these strains, and pyrosequence analyses of the genomes of both strains confirmed the absence of genes involved in ganglioside mimicry. The capsule polysaccharide (CPS) of BH-01-0142 was determined to be composed of galactose (Gal), 6-deoxy-ido-heptose, and, in smaller amounts, d-glycero-d-ido-heptose, and the CPS of CG8421 was observed to contain Gal, 6-deoxy-altro-heptose, N-acetyl-glucosamine, and minor amounts of 6-deoxy-3-O-Me-altro-heptose. Both CPSs were shown to carry O-methyl-phosphoramidate. The two genomes contained strain-specific zones, some of which could be traced to a plasmid origin, and both contained a large chromosomal insertion related to the CJEI3 element of C. jejuni RM1221. The genomes of both strains shared a high degree of similarity to each other and, with the exception of the capsule locus of CG8421, to the type strain of the HS3 serotype, TGH9011. PMID:18809665

Proteolytic processing of connective tissue growth factor in normal ocular tissues and during corneal wound healing.

PubMed

Robinson, Paulette M; Smith, Tyler S; Patel, Dilan; Dave, Meera; Lewin, Alfred S; Pi, Liya; Scott, Edward W; Tuli, Sonal S; Schultz, Gregory S

2012-12-13

Connective tissue growth factor (CTGF) is a fibrogenic cytokine that is up-regulated by TGF-β and mediates most key fibrotic actions of TGF-β, including stimulation of synthesis of extracellular matrix and differentiation of fibroblasts into myofibroblasts. This study addresses the role of proteolytic processing of CTGF in human corneal fibroblasts (HCF) stimulated with TGF-β, normal ocular tissues and wounded corneas. Proteolytic processing of CTGF in HCF cultures, normal animal eyes, and excimer laser wounded rat corneas were examined by Western blot. The identity of a 21-kDa band was determined by tandem mass spectrometry, and possible alternative splice variants of CTGF were assessed by 5' Rapid Amplification of cDNA Ends (RACE). HCF stimulated by TGF-β contained full length 38-kDa CTGF and fragments of 25, 21, 18, and 13 kDa, while conditioned medium contained full length 38- and a 21-kDa fragment of CTGF that contained the middle "hinge" region of CTGF. Fragmentation of recombinant CTGF incubated in HCF extracts was blocked by the aspartate protease inhibitor, pepstatin. Normal mouse, rat, and rabbit whole eyes and rabbit ocular tissues contained abundant amounts of C-terminal 25- and 21-kDa fragments and trace amounts of 38-kDa CTGF, although no alternative transcripts were detected. All forms of CTGF (38, 25, and 21 kDa) were detected during healing of excimer ablated rat corneas, peaking on day 11. Proteolytic processing of 38-kDa CTGF occurs during corneal wound healing, which may have important implications in regulation of corneal scar formation.

Simultaneous visualization of the subfemtomolar expression of microRNA and microRNA target gene using HILO microscopy.

PubMed

Lin, Yi-Zhen; Ou, Da-Liang; Chang, Hsin-Yuan; Lin, Wei-Yu; Hsu, Chiun; Chang, Po-Ling

2017-09-01

The family of microRNAs (miRNAs) not only plays an important role in gene regulation but is also useful for the diagnosis of diseases. A reliable method with high sensitivity may allow researchers to detect slight fluctuations in ultra-trace amounts of miRNA. In this study, we propose a sensitive imaging method for the direct probing of miR-10b (miR-10b-3p, also called miR-10b*) and its target ( HOXD10 mRNA) in fixed cells based on the specific recognition of molecular beacons combined with highly inclined and laminated optical sheet (HILO) fluorescence microscopy. The designed dye-quencher-labelled molecular beacons offer excellent efficiencies of fluorescence resonance energy transfer that allow us to detect miRNA and the target mRNA simultaneously in hepatocellular carcinoma cells using HILO fluorescence microscopy. Not only can the basal trace amount of miRNA be observed in each individual cell, but the obtained images also indicate that this method is useful for monitoring the fluctuations in ultra-trace amounts of miRNA when the cells are transfected with a miRNA precursor or a miRNA inhibitor (anti-miR). Furthermore, a reasonable causal relation between the miR-10b and HOXD10 expression levels was observed in miR-10b* precursor-transfected cells and miR-10b* inhibitor-transfected cells. The trends of the miRNA alterations obtained using HILO microscopy completely matched the RT-qPCR data and showed remarkable reproducibility (the coefficient of variation [CV] = 0.86%) and sensitivity (<1.0 fM). This proposed imaging method appears to be useful for the simultaneous visualisation of ultra-trace amounts of miRNA and target mRNA and excludes the procedures for RNA extraction and amplification. Therefore, the visualisation of miRNA and the target mRNA should facilitate the exploration of the functions of ultra-trace amounts of miRNA in fixed cells in biological studies and may serve as a powerful tool for diagnoses based on circulating cancer cells.

ENHANCED FORMATION OF DIOXINS AND FURANS FROM COMBUSTION DEVICES BY ADDITION OF TRACE QUANTITIES OF BROMINE

EPA Science Inventory

Past pilot-scale experimental studies have shown a dramatic increase in the formation of certain chlorinated products of incomplete combustion (PICs) caused by the addition of trace amounts of bromine (Br). Emissions of trichloroethylene and tetrachloorethylene, generated as PICs...

Carbon nanotube TiO2 hybrid films for detecting traces of O2

NASA Astrophysics Data System (ADS)

Llobet, E.; Espinosa, E. H.; Sotter, E.; Ionescu, R.; Vilanova, X.; Torres, J.; Felten, A.; Pireaux, J. J.; Ke, X.; Van Tendeloo, G.; Renaux, F.; Paint, Y.; Hecq, M.; Bittencourt, C.

2008-09-01

Hybrid titania films have been prepared using an adapted sol-gel method for obtaining well-dispersed hydrogen plasma-treated multiwall carbon nanotubes in either pure titania or Nb-doped titania. The drop-coating method has been used to fabricate resistive oxygen sensors based on titania or on titania and carbon nanotube hybrids. Morphology and composition studies have revealed that the dispersion of low amounts of carbon nanotubes within the titania matrix does not significantly alter its crystallization behaviour. The gas sensitivity studies performed on the different samples have shown that the hybrid layers based on titania and carbon nanotubes possess an unprecedented responsiveness towards oxygen (i.e. more than four times higher than that shown by optimized Nb-doped TiO2 films). Furthermore, hybrid sensors containing carbon nanotubes respond at significantly lower operating temperatures than their non-hybrid counterparts. These new hybrid sensors show a strong potential for monitoring traces of oxygen (i.e. <=10 ppm) in a flow of CO2, which is of interest for the beverage industry.

The differentiation of eucrites: The role of in situ crystallization

NASA Astrophysics Data System (ADS)

Barrat, J. A.; Blichert-Toft, J.; Gillet, Ph.; Keller, F.

2000-09-01

We report on major and trace element analyses of 17 eucrites, including three cumulate eucrites (Binda, Moore County, and Serra de Magé), determined by, respectively, ICP-AES and ICP-MS. The results obtained for Binda and Moore County are consistent with the model of Treiman (1997) for the formation of cumulate eucrites, which holds that these meteorites were produced from a eucritic melt. Our sample of Serra de Magé contains unusually large amounts of pyroxene and probably an accessory phase rich in HREEs and is therefore not representative of this eucrite as known from literature data. Our results for the noncumulate eucrites Bereba, Bouvante, Cachari, Caldera, Camel Donga, Ibitira, Jonzac, Juvinas, Lakangaon, Millbillillie, Padvarninkai, Pasamonte, Sioux County and Stannern are in good agreement with literature data. The observed decoupling between major and trace elements for noncumulate eucrites can be explained by in-situ crystallization during the differentiation of an asteroidal magma ocean. This model can further account for both the Nuevo Laredo and the Stannern trends but has as a consequence that none of the analyzed eucrites represents a primary melt.

Effects of Silver and Other Metals on the Cytoskeleton

NASA Technical Reports Server (NTRS)

Conrad, Gary W.

1997-01-01

Directly or indirectly, trace concentrations of silver ion (Ag(+)) stabilize microtubules (Conrad, A.H., et al. Cell Motil. & Cytoskel. 27:117-132), as does taxol (Conrad, A.H., et al. J. Exp. Zool. 262:154-165), an effect with major consequences for cellular shape changes and development. Polymerization of microtubules is gravity-sensitive (Tabony and Job, Proc. Natl. Acad. Sci. USA 89:6948-6952), so trace amounts of Ag(+) may alter cellular ability to respond to gravity. If Ag electrolysis is used to purify water on NASA space vehicles, plants and animals/astronauts will be exposed continuously to Ag(+), a regimen with unknown cellular and developmental consequences. Fertilized eggs of the marine mudsnail, Ilyanassa obsoleta, are the cells in which the effects of A(+) on microtubules were discovered. They distribute visible cytoplasmic contents according to gravity and contain cytoplasmic morphogenetic determinants for heart development. The objectives are to determine if the effects of Ag(+), AU(3+), (of biosensor relevance), or Gd(3+) (inhibitor of some stretch-activated ion channels) on the cytoskeleton (in the presence and absence of mechanical loading) will affect cellular responses to gravity.

Isolation and characterization of a newly identified impurity in methamphetamine synthesized via reductive amination of 1-phenyl-2-propanone (P2P) made from phenylacetic acid/lead (II) acetate.

PubMed

Toske, Steven G; McConnell, Jennifer B; Brown, Jaclyn L; Tuten, Jennifer M; Miller, Erin E; Phillips, Monica Z; Vazquez, Etienne R; Lurie, Ira S; Hays, Patrick A; Guest, Elizabeth M

2017-03-01

A trace processing impurity found in certain methamphetamine exhibits was isolated and identified as trans-N-methyl-4-methyl-5-phenyl-4-penten-2-amine hydrochloride (1). It was determined that this impurity was produced via reductive amination of trans-4-methyl-5-phenyl-4-penten-2-one (4), which was one of a cluster of related ketones generated during the synthesis of 1-phenyl-2-propanone (P2P) from phenylacetic acid and lead (II) acetate. This two-step sequence resulted in methamphetamine containing elevated levels of 1. In contrast, methamphetamine produced from P2P made by other methods produced insignificant (ultra-trace or undetectable) amounts of 1. These results confirm that 1 is a synthetic marker compound for the phenylacetic acid and lead (II) acetate method. Analytical data for 1 and 4, and a postulated mechanism for the production of 4, are presented. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Effects of rutin supplementation on antioxidant status and iron, copper, and zinc contents in mouse liver and brain.

PubMed

Gao, Zhonghong; Xu, Huibi; Huang, Kaixun

2002-09-01

The effect of rutin on total antioxidant status as well as on trace elements such as iron, copper, and zinc in mouse liver and brain were studied. Mice were administrated with 0.75 g/kg or 2.25 g/kg P. O. of rutin for 30 d consecutively. Following the treatment, the activity of total antioxidant status, catalase, Cu,Zn-superoxide dismutase, Mn-superoxide dismutase, zinc, copper, and iron were measured in mouse liver and brain. The results showed that rutin significantly increased the antioxidant status and Mn-superoxide dismutase activities in mouse liver, but it had no effect on these variables in the brain. Treatment with a higher concentration of rutin significantly decreased catalase activity and iron, zinc, and copper contents in mouse liver; it also resulted in a slower weight gain for the first 20 d. These results indicate that rutin taken in proper amount can effectively improve antioxidant status, whereas at an increased dosage, it may cause trace element (such as iron, zinc, and copper) deficiencies and a decrease in the activities of related metal-containing enzymes.

Should bioactive trace elements not recognized as essential, but with beneficial health effects, have intake recommendations.

PubMed

Nielsen, Forrest H

2014-10-01

Today, most nutritionists do not consider a trace element essential unless it has a defined biochemical function in higher animals or humans. As a result, even though it has been found that trace elements such as boron and silicon have beneficial bioactivity in higher animals and humans, they generally receive limited attention or mention when dietary guidelines or intake recommendations are formulated. Recently, the possibility of providing dietary intake recommendations such as an adequate intake (AI) for some bioactive food components (e.g., flavonoids) has been discussed. Boron, chromium, nickel, and silicon are bioactive food components that provide beneficial health effects by plausible mechanisms of action in nutritional and supra nutritional amounts, and thus should be included in the discussions. Although the science base may not be considered adequate for establishing AIs, a significant number of findings suggest that statements about these trace elements should be included when dietary intake guidance is formulated. An appropriate recommendation may be that diets should include foods that would provide trace elements not currently recognized as essential in amounts shown to reduce the risk of chronic disease and/or promote health and well-being. Published by Elsevier GmbH.

Determination of the D and L isomers of some protein amino acids present in soils

NASA Technical Reports Server (NTRS)

Pollock, G. E.; Cheng, C.-N.; Cronin, S. E.

1977-01-01

The D and L isomers of some protein amino acids present in soils were measured by using a gas chromatographic technique. The results of two processing procedures were compared to determine the better method. Results of the comparison indicated that the determination of D and L percentages requires amino acid purification if one is to obtain accurate data. It was found that very significant amounts of D-alanine, D-aspartic acid, and D-glutamic acid were present in the contemporary soils studied. Valine, isoleucine, leucine, proline, and phenylalanine generally contained only a trace to very small amounts of the D isomer. It is probable that the D-amino acids from the alanine, aspartic, and glutamic acids are contributed to the soil primarily via microorganisms. The finding of very significant quantities of some D-amino acids (about 5-16%) in present-day soils may alert some investigators of geological sediments to a possible problem in using amino acid racemization as an age-dating technique.

Oil and gas exploration system and method for detecting trace amounts of hydrocarbon gases in the atmosphere

DOEpatents

Wamsley, Paula R.; Weimer, Carl S.; Nelson, Loren D.; O'Brien, Martin J.

2003-01-01

An oil and gas exploration system and method for land and airborne operations, the system and method used for locating subsurface hydrocarbon deposits based upon a remote detection of trace amounts of gases in the atmosphere. The detection of one or more target gases in the atmosphere is used to indicate a possible subsurface oil and gas deposit. By mapping a plurality of gas targets over a selected survey area, the survey area can be analyzed for measurable concentration anomalies. The anomalies are interpreted along with other exploration data to evaluate the value of an underground deposit. The system includes a differential absorption lidar (DIAL) system with a spectroscopic grade laser light and a light detector. The laser light is continuously tunable in a mid-infrared range, 2 to 5 micrometers, for choosing appropriate wavelengths to measure different gases and avoid absorption bands of interference gases. The laser light has sufficient optical energy to measure atmospheric concentrations of a gas over a path as long as a mile and greater. The detection of the gas is based on optical absorption measurements at specific wavelengths in the open atmosphere. Light that is detected using the light detector contains an absorption signature acquired as the light travels through the atmosphere from the laser source and back to the light detector. The absorption signature of each gas is processed and then analyzed to determine if a potential anomaly exists.

Extraction and Determination of Trace Amounts of p-Coumaric Acid in Vinegar, Carrot Juice, and Seed Extract from Silybum marianum (L.) Gaertn.

PubMed

Khani, Rouhollah; Rostami, Zeinab; Bagherzade, Ghodsieh; Khojeh, Vahid

2018-03-01

In this study, for the monitoring and quantification of p-coumaric acid (p-CA) in vinegar, carrot juice, and seed extract from the plant species Silybum marianum (L.) Gaertn, an efficient and low-cost analytical method has been applied. For this purpose, a dispersive liquid-liquid microextraction (DLLME) method, followed by UV-Vis spectrophotometric detection, was used. To form a cloudy solution, a binary mixture containing ethanol as a disperser solvent and chloroform as an extraction solvent was rapidly injected by syringe into a sample solution containing p-CA. After centrifugation, dilution of the obtained organic phase was done with the proper amount of ethanol, and the phase was transferred into a micro cell for subsequent measurement. Some effective parameters for the DLLME method, such as the volume of disperser solvent and extraction solvent, pH, and salt concentration were inspected by a 24 full factorial central composite design using design Export Software. Under the optimized conditions, linearity was between 10 and 150 ng/mL, and the LOD was 2.3 ng/mL. The results of the proposed method were similar to the obtained results using a GC with flame-ionization detection method.

HPLC study of migration of terephthalic acid and isophthalic acid from PET bottles into edible oils.

PubMed

Khaneghah, Amin Mousavi; Limbo, Sara; Shoeibi, Shahram; Mazinani, Somayeh

2014-08-01

Polyethylene terephthalate (PET) containers for food oil packaging were evaluated with a newly established determination method for terephthalic acid (TPA) and isophthalic acid (IPA). The analysis of monomers, TPA and IPA that migrate from PET bottles into oils was performed using high-pressure liquid chromatography with a diode array detector. Three types of commercial oils (sunflower oil, canola oil and blended oil which included sunflower oil, soy bean oil and cottonseed oil) were bottled in PET containers. These samples were incubated for 10 days at 49 °C as accelerated test condition. The means of recovery for this method varied from 70% to 72% and from 101% to 111% for TPA and IPA, respectively. The results showed that the amounts of specific migration of TPA and IPA into the samples conform to European Union legislation that identifies specific migration limits. More important, the results highlighted a different behavior of migration as a function of the fatty acid profile. Previous investigations have been performed with food simulants such as HB307 or 20% ethanol but our study used real food samples and determined trace amounts of the migrated compounds. Further investigation will be needed to better explain the influence of fatty acid conformation on migration of PET monomers. © 2013 Society of Chemical Industry.

Heterogeneous Atmospheric Chemistry of Lead Oxide Particles with Nitrogen Dioxide Increases Lead Solubility: Environmental and Health Implications

PubMed Central

Baltrusaitis, Jonas; Chen, Haihan; Rubasinghege, Gayan

2012-01-01

Heterogeneous chemistry of nitrogen dioxide with lead-containing particles is investigated to better understand lead metal mobilization in the environment. In particular, PbO particles, a model lead-containing compound due to its wide spread presence as a component of lead paint and as naturally occurring minerals, massicot and litharge, are exposed to nitrogen dioxide at different relative humidity. X-ray photoelectron spectroscopy (XPS) shows that upon exposure to nitrogen dioxide the surface of PbO particles react to form adsorbed nitrates and lead nitrate thin films with the extent of formation of nitrate relative humidity dependent. Surface adsorbed nitrate increases the amount of dissolved lead. These reacted particles are found to have an increase in the amount of lead that dissolves in aqueous suspensions at circumneutral pH compared to unreacted particles. These results point to the potential importance and impact that heterogeneous chemistry with trace atmospheric gases can have on increasing solubility and therefore the mobilization of heavy metals, such as lead, in the environment. This study also show that surface intermediates, such as adsorbed nitrates, that form can yield higher concentrations of lead in water systems. In the environment, these water systems can include drinking water, ground water, estuaries and lakes. PMID:23057678

Physiological Effects of Trace Elements and Chemicals in Water

ERIC Educational Resources Information Center

Varma, M. M.; And Others

1976-01-01

The physiological effects on humans and animals of trace amounts of organic and unorganic pollutants in natural and waste waters are examined. The sensitivity of particular organs and species is emphasized. Substances reviewed include mercury, arsenic, cadmium, lead, chromium, fluorides, nitrates and organics, including polychlounated biphenyls.…

A pilot study on nicotine residues in houses of electronic cigarette users, tobacco smokers, and non-users of nicotine-containing products.

PubMed

Bush, Derek; Goniewicz, Maciej L

2015-06-01

Nicotine deposited on the surfaces has been shown to react with airborne chemicals leading to formation of carcinogens and contributing to thirdhand exposure. While prior studies revealed nicotine residues in tobacco smokers' homes, none have examined the nicotine residue in electronic cigarette (e-cigarette) users' homes. We measured nicotine on the surfaces in households of 8 e-cigarette users, 6 cigarette smokers, and 8 non-users of nicotine-containing products in Western New York, USA. Three surface wipe samples were taken from the floor, wall and window. Nicotine was extracted from the wipes and analyzed using gas chromatography. Half of the e-cigarette users' homes had detectable levels of nicotine on surfaces whereas nicotine was found in all of the tobacco cigarette smokers' homes. Trace amounts of nicotine were also detected in half of the homes of non-users of nicotine-containing products. Nicotine levels in e-cigarette users homes was significantly lower than that found in cigarette smokers homes (average concentration 7.7±17.2 vs. 1303±2676 μg/m2; p<0.05). There was no significant difference in the amount of nicotine in homes of e-cigarette users and non-users (p>0.05). Nicotine is a common contaminant found on indoor surfaces. Using e-cigarettes indoors leads to significantly less thirdhand exposure to nicotine compared to smoking tobacco cigarettes. Copyright © 2015 Elsevier B.V. All rights reserved.

Occurrence and accumulation of pesticides and organic contaminants in river sediment, water and clam tissues from the San Joaquin River and tributaries, California

USGS Publications Warehouse

Pereira, W.E.; Domagalski, Joseph L.; Hostettler, F.D.; Brown, L.R.; Rapp, J.B.

1996-01-01

A study was conducted in 1992 to assess the effects of anthropogenic activities and land use on the water quality of the San Joaquin River and its major tributaries. This study focused on pesticides and organic contaminants, looking at distributions of contaminants in water, bed and suspended sediment, and the bivalve Corbicula fluminea. Results indicated that this river system is affected by agricultural practices and urban runoff. Sediments from Dry Creek contained elevated concentrations of polycyclic aromatic hydrocarbons (PAHs), possibly derived from urban runoff from the city of Modesto; suspended sediments contained elevated amounts of chlordane. Trace levels of triazine herbicides atrazine and simazine were present in water at most sites. Sediments, water, and bivalves from Orestimba Creek, a westside tributary draining agricultural areas, contained the greatest levels of DDT (1,1,1-trichloro-2-2-bis[p-chlorophenyl]ethane), and its degradates DDD (1,1-dichloro-2,2-bis[p-chlorophenyl]ethane), and DDE (1,1-dichloro-2,2- bis[p-chlorophenyl]ethylene). Sediment adsorption co efficients (K(oc)), and bioconcentration factors (BCF) in Corbicula of DDT, DDD, and DDE at Orestimba Creek were greater than predicted values. Streams of the western San Joaquin Valley can potentially transport significant amounts of chlorinated pesticides to the San Joaquin River, the delta, and San Francisco Bay. Organochlorine compounds accumulate in bivalves and sediment and may pose a problem to other biotic species in this watershed.

Uranium mineralization in the Wilson Creek and Cranberry Gneisses and the Grandfather Mountain Formation, North Carolina and Tennessee. National Uranium Resource Evaluation

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

Wagener, H.D.; McHone, J.G.

1982-10-01

Detailed petrologic investigations were conducted at 74 anomalies that have surface radioactivities of 5 to 300 times background in the Grandfather Mountain region of North Carolina and Tennessee. One or more specimens of radioactive rock and one specimen of nonanomalous (barren) rock were taken for chemical analysis from each of the 74 sites. The specimens were analyzed fluorometrically for uranium (U/sub 3/O/sub 8/) and for 29 other elements by emission spectroscopy. Of the radioactive specimens, 23 contained less than 100 ppM U/sub 3/O/sub 8/ and were either depleted in uranium because of leaching or were rich in thorium; 25 containedmore » more than 500 ppM U/sub 3/O/sub 8/, with a maximum of 33,000 ppM. Specimens collected as barren contained up to 65 ppM U/sub 3/O/sub 8/. The more uraniferous rocks of the region tend to contain the larger concentrations of trace amounts of base metals.« less

Field determination of microgram quantities of niobium in rocks

USGS Publications Warehouse

Ward, F.N.; Marranzino, A.P.

1955-01-01

A rapid, simple, and moderately accurate method was needed for the determination of traces of niobium in rocks. The method developed is based on the reaction of niobium(V) with thiocyanate ion in a 4M hydrochloric acid and 0.5M tartaric acid medium, after which the complex is extracted with ethyl ether. The proposed procedure is applicable to rocks containing from 50 to 2000 p.p.m. of niobium, and, with modifications, can be used on rocks containing larger amounts. Five determinations on two rocks containing 100 p.p.m. or less of niobium agree within 5 p.p.m. of the mean, and the confidence limits at the 95% level are, respectively, ??6 and ??4 p.p.m. The addition of acetone to the ether extract of the niobium thiocyanate inhibits the polymerization of the thiocyanate ion and stabilizes the solution for at least 20 hours. The proposed procedure permits the determination of 20 ?? of niobium in the presence of 1000 ?? of iron, titanium, or uranium; 500 ?? of vanadium; or 100 ?? of tungsten or molybdenum or both.

Piezoelectric trace vapor calibrator

NASA Astrophysics Data System (ADS)

Verkouteren, R. Michael; Gillen, Greg; Taylor, David W.

2006-08-01

The design and performance of a vapor generator for calibration and testing of trace chemical sensors are described. The device utilizes piezoelectric ink-jet nozzles to dispense and vaporize precisely known amounts of analyte solutions as monodisperse droplets onto a hot ceramic surface, where the generated vapors are mixed with air before exiting the device. Injected droplets are monitored by microscope with strobed illumination, and the reproducibility of droplet volumes is optimized by adjustment of piezoelectric wave form parameters. Complete vaporization of the droplets occurs only across a 10°C window within the transition boiling regime of the solvent, and the minimum and maximum rates of trace analyte that may be injected and evaporated are determined by thermodynamic principles and empirical observations of droplet formation and stability. By varying solution concentrations, droplet injection rates, air flow, and the number of active nozzles, the system is designed to deliver—on demand—continuous vapor concentrations across more than six orders of magnitude (nominally 290fg/lto1.05μg/l). Vapor pulses containing femtogram to microgram quantities of analyte may also be generated. Calibrated ranges of three explosive vapors at ng/l levels were generated by the device and directly measured by ion mobility spectrometry (IMS). These data demonstrate expected linear trends within the limited working range of the IMS detector and also exhibit subtle nonlinear behavior from the IMS measurement process.

High cell density media for Escherichia coli are generally designed for aerobic cultivations – consequences for large-scale bioprocesses and shake flask cultures

PubMed Central

Soini, Jaakko; Ukkonen, Kaisa; Neubauer, Peter

2008-01-01

Background For the cultivation of Escherichia coli in bioreactors trace element solutions are generally designed for optimal growth under aerobic conditions. They do normally not contain selenium and nickel. Molybdenum is only contained in few of them. These elements are part of the formate hydrogen lyase (FHL) complex which is induced under anaerobic conditions. As it is generally known that oxygen limitation appears in shake flask cultures and locally in large-scale bioreactors, function of the FHL complex may influence the process behaviour. Formate has been described to accumulate in large-scale cultures and may have toxic effects on E. coli. Although the anaerobic metabolism of E. coli is well studied, reference data which estimate the impact of the FHL complex on bioprocesses of E. coli with oxygen limitation have so far not been published, but are important for a better process understanding. Results Two sets of fed-batch cultures with conditions triggering oxygen limitation and formate accumulation were performed. Permanent oxygen limitation which is typical for shake flask cultures was caused in a bioreactor by reduction of the agitation rate. Transient oxygen limitation, which has been described to eventually occur in the feed-zone of large-scale bioreactors, was mimicked in a two-compartment scale-down bioreactor consisting of a stirred tank reactor and a plug flow reactor (PFR) with continuous glucose feeding into the PFR. In both models formate accumulated up to about 20 mM in the culture medium without addition of selenium, molybdenum and nickel. By addition of these trace elements the formate accumulation decreased below the level observed in well-mixed laboratory-scale cultures. Interestingly, addition of the extra trace elements caused accumulation of large amounts of lactate and reduced biomass yield in the simulator with permanent oxygen limitation, but not in the scale-down two-compartment bioreactor. Conclusion The accumulation of formate in oxygen limited cultivations of E. coli can be fully prevented by addition of the trace elements selenium, nickel and molybdenum, necessary for the function of FHL complex. For large-scale cultivations, if glucose gradients are likely, the results from the two-compartment scale-down bioreactor indicate that the addition of the extra trace elements is beneficial. No negative effects on the biomass yield or on any other bioprocess parameters could be observed in cultures with the extra trace elements if the cells were repeatedly exposed to transient oxygen limitation. PMID:18687130

Remediation using trace element humate surfactant

DOEpatents

Riddle, Catherine Lynn; Taylor, Steven Cheney; Bruhn, Debra Fox

2016-08-30

A method of remediation at a remediation site having one or more undesirable conditions in which one or more soil characteristics, preferably soil pH and/or elemental concentrations, are measured at a remediation site. A trace element humate surfactant composition is prepared comprising a humate solution, element solution and at least one surfactant. The prepared trace element humate surfactant composition is then dispensed onto the remediation site whereby the trace element humate surfactant composition will reduce the amount of undesirable compounds by promoting growth of native species activity. By promoting native species activity, remediation occurs quickly and environmental impact is minimal.

Chemical Properties, Decomposition, and Methane Production of Tertiary Relict Plant Litters: Implications for Atmospheric Trace Gas Production in the Early Tertiary

NASA Astrophysics Data System (ADS)

Yavitt, J. B.; Bartella, T. M.; Williams, C. J.

2006-12-01

Throughout the early Tertiary (ca. 65-38 Ma) Taxodiaceae-dominated (redwood) wetland forests occupied the high latitudes and were circumpolar in their distribution. Many of these forests had high standing biomass with moderate primary productivity. The geographic extent and amount of Tertiary coals and fossil forests throughout Arctic Canada suggests large areas of wetland forests that may have cycled substantial quantities of carbon, particularly methane until they were replaced by cold tolerant Pinus, Picea, and Larix following climatic cooling associated with the Terminal Eocene Event. To test this hypothesis we compared physiochemical properties, decomposition, and trace gas production of litter from extant Metasequoia, Pinus, Picea, and Larix. Initial results from plantation-grown trees indicate Metasequoia litter is a better source of labile organic substrate than pinaceous litter. Metasequoia litter contained the least lignin and highest amounts of water-soluble compounds of the four litter types studied. Analysis of the lignin structure using cupric oxide oxidation indicates that Metasequoia lignin is enriched in 4'-hydroxyacetophenone and 4'- Hydroxy-3'-methoxyacetophenone relative to the pinaceous litter. In a 12-month decomposition study using litterbags, average litter mass loss was greater for Metasequoia litter (62%) compared to the pinaceous species (50%). Moreover, Metasequoia litter incubated under anoxic conditions produced nearly twice as much CO2 (ca. 4.2 umol/g.day) and CH4 (2.1 umol/g.day) as the pinaceous litter (2.4 umol/g.day for CO2; 1.2 umol/g.day for CH4). Our results support the idea of greater decomposability and palatability of Metasequoia litter as compared to Larix, Picea, or Pinus. Provided that the biochemical properties of Metasequoia have remained relatively stable through geologic time, it appears that early Tertiary Metasequoia-dominated wetland forests may have had higher microbial driven trace gas production than the Pinaceae-dominated forests that replaced them in the late Tertiary.

Paragenetic and minor- and trace-element studies of Mississippi Valley-type ore deposits of the Silesian-Cracow district, Poland

USGS Publications Warehouse

Viets, J.G.; Leach, D.L.; Lichte, F.E.; Hopkins, R.T.; Gent, C.A.; Powell, J.W.

1996-01-01

Paragenetic and minor- and trace-element studies were conducted on samples of epigenetic ore and gangue minerals collected from mines and drill core in the Silesian-Cracow (S-C) district of southern Poland. Four discrete mineral suites representing four mineralizing stages can be identified throughout the district. The earliest epigenetic minerals deposited during stage 1 consist of a late dolomite cement together with minor pyrite and marcasite. Stage 2 was the first ore-forming stage and included repetitive deposition of sphalerite and galena in a variety of morphologies. Stage 3 abruptly followed the first ore stage and deposited marcasite and pyrite with variable amounts of late sphalerite and galena. In the samples studied, minerals deposited during stage 3 are predominately marcasite-pyrite with minor sphalerite and galena in the Pomorzany and Olkusz mines, whereas, at the Trzebionka mine, stage 3 mineralization deposited mostly galena and sphalerite with little marcasite or pyrite. Stage 4 minerals include contains barite, followed by calcite, with very minor pyrite and a rare, late granular sphalerite. Compared to other major Mississippi Valley-type (MVT) districts of the world, the Silesian-Cracow district contains sphalerite with the second largest range in Ag concentrations and the largest range in Fe and Cd concentrations of any district. Unlike in other districts, very wide ranges in minor- and trace-element concentrations are also observed in paragenetically equivalent samples collected throughout the district. This wide range indicates that the minor- and trace-element content of the ore-forming environment was highly variable, both spatially and temporally, and suggests that the hydrologic system that the ore fluids traversed from their basinal source was very complex. Throughout the district, a significant increase in Tl, Ge, and As concentrations is accompanied by a lightening of sulfur isotopes between stage 2 and stage 3 minerals. This change appears to record a major district-scale hydrologic event that probably reflects the introduction of fluids with significantly different geochemistry than that of earlier ore-forming fluids.

METHOD FOR PURIFYING URANIUM

DOEpatents

Kennedy, J.W.; Segre, E.G.

1958-08-26

A method is presented for obtaining a compound of uranium in an extremely pure state and in such a condition that it can be used in determinations of the isotopic composition of uranium. Uranium deposited in calutron receivers is removed therefrom by washing with cold nitric acid and the resulting solution, coataining uranium and trace amounts of various impurities, such as Fe, Ag, Zn, Pb, and Ni, is then subjected to various analytical manipulations to obtain an impurity-free uranium containing solution. This solution is then evaporated on a platinum disk and the residue is ignited converting it to U2/sub 3//sub 8/. The platinum disk having such a thin film of pure U/sub 2/O/sub 8/ is suitable for use with isotopic determination techaiques.

Copper crystallite in carbon molecular sieves for selective oxygen removal

NASA Technical Reports Server (NTRS)

Sharma, Pramod K. (Inventor); Seshan, Panchalam K. (Inventor)

1993-01-01

Carbon molecular sieves modified by the incorporation of finely divided elemental copper useful for the selective sorption of oxygen at elevated temperatures. The carbon molecular sieves can be regenerated by reduction with hydrogen. The copper modified carbon molecular sieves are prepared by pyrolysis of a mixture of a copper-containing material and polyfurfuryl alcohol to form a sorbent precursor. The sorbent precursors are then heated and reduced to produce copper modified carbon molecular sieves. The copper modified carbon molecular sieves are useful for sorption of all concentrations of oxygen at temperatures up to about 200.degree. C. They are also useful for removal of trace amount of oxygen from gases at temperatures up to about 600.degree. C.

Determination of trace amounts of chemical warfare agent degradation products in decontamination solutions with NMR spectroscopy.

PubMed

Koskela, Harri; Rapinoja, Marja-Leena; Kuitunen, Marja-Leena; Vanninen, Paula

2007-12-01

Decontamination solutions are used for an efficient detoxification of chemical warfare agents (CWAs). As these solutions can be composed of strong alkaline chemicals with hydrolyzing and oxidizing properties, the analysis of CWA degradation products in trace levels from these solutions imposes a challenge for any analytical technique. Here, we present results of application of nuclear magnetic resonance spectroscopy for analysis of trace amounts of CWA degradation products in several untreated decontamination solutions. Degradation products of the nerve agents sarin, soman, and VX were selectively monitored with substantially reduced interference of background signals by 1D 1H-31P heteronuclear single quantum coherence (HSQC) spectrometry. The detection limit of the chemicals was at the low part-per-million level (2-10 microg/mL) in all studied solutions. In addition, the concentration of the degradation products was obtained with sufficient confidence with external standards.

Privacy Vulnerability of Published Anonymous Mobility Traces

DOE PAGES

Ma, Chris Y. T.; Yau, David K. Y.; Yip, Nung Kwan; ...

2013-06-01

Mobility traces of people and vehicles have been collected and published to assist the design and evaluation of mobile networks, such as large-scale urban sensing networks. Although the published traces are often made anonymous in that the true identities of nodes are replaced by random identifiers, the privacy concern remains. This is because in real life, nodes are open to observations in public spaces, or they may voluntarily or inadvertently disclose partial knowledge of their whereabouts. Thus, snapshots of nodes’ location information can be learned by interested third parties, e.g., directly through chance/engineered meetings between the nodes and their observers,more » or indirectly through casual conversations or other information sources about people. In this paper, we investigate how an adversary, when equipped with a small amount of the snapshot information termed as side information, can infer an extended view of the whereabouts of a victim node appearing in an anonymous trace. Our results quantify the loss of victim nodes’ privacy as a function of the nodal mobility, the inference strategies of adversaries, and any noise that may appear in the trace or the side information. Generally, our results indicate that the privacy concern is significant in that a relatively small amount of side information is sufficient for the adversary to infer the true identity (either uniquely or with high probability) of a victim in a set of anonymous traces. For instance, an adversary is able to identify the trace of 30%-50% of the victims when she has collected 10 pieces of side information about a victim.« less

Carbon and Aerosol Emissions from Biomass Fires in Mexico

NASA Astrophysics Data System (ADS)

Hao, W. M.; Flores Garnica, G.; Baker, S. P.; Urbanski, S. P.

2009-12-01

Biomass burning is an important source of many atmospheric greenhouse gases and photochemically reactive trace gases. There are limited data available on the spatial and temporal extent of biomass fires and associated trace gas and aerosol emissions in Mexico. Biomass burning is a unique source of these gases and aerosols, in comparison to industrial and biogenic sources, because the locations of fires vary considerably both daily and seasonally and depend on human activities and meteorological conditions. In Mexico, the fire season starts in January and about two-thirds of the fires occur in April and May. The amount of trace gases and aerosols emitted by fires spatially and temporally is a major uncertainty in quantifying the impact of fire emissions on regional atmospheric chemical composition. To quantify emissions, it is necessary to know the type of vegetation, the burned area, the amount of biomass burned, and the emission factor of each compound for each ecosystem. In this study biomass burning experiments were conducted in Mexico to measure trace gas emissions from 24 experimental fires and wildfires in semiarid, temperate, and tropical ecosystems from 2005 to 2007. A range of representative vegetation types were selected for ground-based experimental burns to characterize fire emissions from representative Mexico fuels. A third of the country was surveyed each year, beginning in the north. The fire experiments in the first year were conducted in Chihuahua, Nuevo Leon, and Tamaulipas states in pine forest, oak forest, grass, and chaparral. The second-year fire experiments were conducted on pine forest, oak forest, shrub, agricultural, grass, and herbaceous fuels in Jalisco, Puebla, and Oaxaca states in central Mexico. The third-year experiments were conducted in pine-oak forests of Chiapas, coastal grass, and low subtropical forest on the Yucatan peninsula. FASS (Fire Atmosphere Sampling System) towers were deployed for the experimental fires. Each FASS system contains 4 electro-polished stainless steel canisters to sample trace gas emissions, with a corresponding set of Teflon filters in the sampling ports to collect PM2.5 particulates. In addition, biomass burning was sampled by aircraft with canisters and real-time instruments as part of the MILAGRO field campaign. We present the emission factors of CO2, CO, CH4, C2-C4 compounds, and PM2.5 for prescribed fires of the major vegetation types in Mexico, as well as for regional wildfires in southern and central Mexico. We will also present a high-resolution vegetation map in Mexico based on the Landsat satellites and the fuel consumption models for various components and sizes of fuels.

Colour and label evaluation of commercial pasteurised red juices and related drinks.

PubMed

Fallico, B; Arena, E; Chiappara, E; Ballistreri, G

2010-01-01

Despite growing demand by consumers for healthy beverages, artificial colours are still widely used. Levels of anthocyanins and artificial colours were determined by HPLC with UV-Vis detection in red orange juices and other red beverages (nectar, juice-based, health, carbonated and sports drinks). The contribution of pigments to the visible colour of the beverage was calculated. Red orange juice samples contained about 34 mg l(-1) of anthocyanins, which were responsible for about 92% of the visible colour. Red juice-based drinks, containing from 0% to 30% of red orange, berry, grape or pomegranate juices, had low levels of anthocyanins (about 7 mg l(-1)) and high levels of E129 (about 32 mg l(-1)), which were responsible for about 90.7% of the colour of these beverages. Red health drinks, enriched with vitamins and polyphenols, contained from 3% to 50% of red fruit juices. Also in this case the E129 levels were higher (about 22 mg l(-1)) than anthocyanins (about 9 mg l(-1)), and were responsible for the colour of the beverages (76.1%). High levels of artificial colours were found in red orange carbonated drinks, but in comparable amounts with those found in the other beverage samples, while anthocyanins were only present in trace amounts. Although all of the beverages claimed to contain red fruits on the labels, no correlation was found between the level of anthocyanins and the declared percentage of red fruits. These labels generally conformed with the requirements of the law, but food product labels can often be misleading to consumers about the real characteristics of the product.

Evaluation of trace elements in selected foods and dietary intake by young children in Thailand.

PubMed

Nookabkaew, S; Rangkadilok, N; Akib, C A; Tuntiwigit, N; Saehun, J; Satayavivad, J

2013-01-01

Elemental concentrations in rice, animal products, eggs, vegetables, fruits, infant formulas and drinking water were determined in 667 food samples randomly collected from local markets, big supermarkets and grocery stores in Bangkok, Thailand, during the period October 2005-August 2008. Samples were digested with nitric acid and analysed by inductively coupled plasma-mass spectrometry. Arsenic and cadmium levels in most foods were below the maximum levels as set by international organisations. Filtered and bottled drinking water, rice, vegetables and banana contained low concentrations of arsenic, cadmium and lead. Non-polished rice had higher magnesium, calcium, manganese, iron and selenium concentrations than polished rice. Banana was a major source for manganese and selenium. Pig kidney and liver contained high levels of arsenic and cadmium. Manganese, cadmium, lead and aluminium concentrations in soybean milk could also be of concern. With respect to food safety for children, the amounts of arsenic and cadmium ingested with poultry, pig liver or rice corresponded to high weekly or monthly intake.

Effect of light elements on the sound velocities in solid iron: Implications for the composition of Earth's core

NASA Astrophysics Data System (ADS)

Badro, James; Fiquet, Guillaume; Guyot, François; Gregoryanz, Eugene; Occelli, Florent; Antonangeli, Daniele; d'Astuto, Matteo

2007-02-01

We measured compressional sound velocities in light element alloys of iron (FeO, FeSi, FeS, and FeS2) at high-pressure by inelastic X-ray scattering. This dataset provides new mineralogical constraints on the composition of Earth's core, and completes the previous sets formed by the pressure-density systematics for these compounds. Based on the combination of these datasets and their comparison with radial seismic models, we propose an average composition model of the Earth's core. We show that the incorporation of small amounts of silicon or oxygen is compatible with geophysical observations and geochemical abundances. The effect of nickel on the calculated light element contents is shown to be negligible. The preferred core model derived from our measurements is an inner core which contains 2.3 wt.% silicon and traces of oxygen, and an outer core containing 2.8 wt.% silicon and around 5.3 wt.% oxygen.

Copper and boron fixation in wood by pyrolytic resins.

PubMed

Mourant, Daniel; Yang, Dian-Qing; Lu, Xiao; Riedl, Bernard; Roy, Christian

2009-02-01

A phenol-formaldehyde (PF)-resin designed to penetrate wood and immobilize copper and boron in wood cells for protection against decay was investigated. The phenol portion of the PF-resin was partially substituted with pyrolysis oil derived from softwood bark. The objective was to reduce the environmental impact associated with the production of petroleum-borne phenol, as well as to improve the product economics. Leaching tests were conducted with three different formulas of resins containing 50%, 75% or 85% by weight of pyrolytic oil on a total phenol basis. The leachates were analyzed for the presence of copper by atomic absorption spectroscopy while inductively coupled plasma spectroscopy was used for boron detection. Copper leaching was reduced up to 18 times when comparing the treatments with and without the resin. Preservative leaching varied between wood species as well as between the resins containing different concentrations of pyrolytic oil. The organic leachates were measured using gas chromatography and mass spectroscopy. Trace amounts of organics, mostly acetic acid, were found in the leachates.

Inorganic particulates in pneumoconiotic lungs of hard metal grinders.

PubMed Central

Rüttner, J R; Spycher, M A; Stolkin, I

1987-01-01

Data from the analysis of lung dust in 16 metal grinders who had been exposed to hard metals between five and 44 years is reported. The mean latent time between the first exposure and analysis in biopsy or necropsy specimens was 33.6 years. Mineralogical and elementary analysis by a variety of techniques showed small or trace amounts of hard metal in all lungs. Many specimens, however, did not contain all hard metal components, cobalt, for example, being detected in four cases only. All the lungs contained quartz and silicates and in most of the necropsy cases carborundum and corundum could also be shown. Histologically no specific pattern was found. The appearances included mixed dust nodular pneumoconiosis, diffuse interstitial lung fibrosis, and foreign body and sarcoid like granulomatous changes. In view of the mixed dust exposure of the hard metal grinders and the variable histological appearance we think that the term "mixed dust pneumoconiosis in hard metal grinders" is more appropriate than "hard metal lung" to describe this condition. PMID:3676118

Convective-diffusion-based fluorescence correlation spectroscopy for detection of a trace amount of E. coli in water.

PubMed

Qing, De-Kui; Mengüç, M Pinar; Payne, Fred A; Danao, Mary-Grace C

2003-06-01

Fluorescence correlation spectroscopy (FCS) is adapted for a new procedure to detect trace amounts of Escherichia coli in water. The present concept is based on convective diffusion rather than Brownian diffusion and employs confocal microscopy as in traditional FCS. With this system it is possible to detect concentrations as small as 1.5 x 10(5) E. coli per milliliter (2.5 x 10(-16) M). This concentration corresponds to an approximately 1.0-nM level of Rhodamine 6G dyes. A detailed analysis of the optical system is presented, and further improvements for the procedure are discussed.

Analysis of volatile organic compounds. [trace amounts of organic volatiles in gas samples

NASA Technical Reports Server (NTRS)

Zlatkis, A. (Inventor)

1977-01-01

An apparatus and method are described for reproducibly analyzing trace amounts of a large number of organic volatiles existing in a gas sample. Direct injection of the trapped volatiles into a cryogenic percolum provides a sharply defined plug. Applications of the method include: (1) analyzing the headspace gas of body fluids and comparing a profile of the organic volatiles with standard profiles for the detection and monitoring of disease; (2) analyzing the headspace gas of foods and beverages and comparing the profile with standard profiles to monitor and control flavor and aroma; and (3) analyses for determining the organic pollutants in air or water samples.

First LC/MS determination of cyanazine amide, cyanazine acid, and cyanazine in groundwater samples

USGS Publications Warehouse

Ferrer, Imma; Thurman, E.M.; Barceló, Damià

2000-01-01

Cyanazine and two of its major metabolites, cyanazine amide and cyanazine acid, were measured at trace levels in groundwater using liquid chromatography/atmospheric pressure chemical ionization/mass spectrometry (LC/APCI/MS). Solid-phase extraction was carried out by passing 20 mL of groundwater sample through a cartridge containing a polymeric phase (PLRP-s), with recoveries ranging from 99 to 108% (n = 5). Using LC/MS detection in positive ion mode, useful structural information was obtained by increasing the fragmentor voltage, thus permitting the unequivocal identification of these compounds in groundwater samples with low sample volumes. The fragmentation of the amide, carboxylic acid, and cyano group was observed for both metabolites and cyanazine, respectively, leading to a diagnostic ion at m/z 214. Method detection limits were in the range of 0.002−0.005 μg/L for the three compounds. Finally, the newly developed method was evaluated for the analysis of groundwater samples from New York containing the compounds under study and presents evidence that the metabolites, cyanazine acid, and cyanazine amide may leach to groundwater and serve as sources for deisopropylatrazine. The combination of on-line SPE and LC/APCI/MS represents an important advance in environmental analysis of herbicide metabolites in groundwater since it demonstrates that trace amounts of polar metabolites may be determined rapidly. Furthermore, the presence of both cyanazine amide and cyanazine acid indicate that another degradation product, deisopropylatrazine, may be occurring at depth because of the subsequent degradation of cyanazine.

Selective and sensitized spectrophotometric determination of trace amounts of Ni(II) ion using α-benzyl dioxime in surfactant media

NASA Astrophysics Data System (ADS)

Ghaedi, Mehrorang

2007-02-01

Highly sensitive and interference-free sensitized spectrophotometric method for the determination of Ni(II) ions is described. The method is based on the reaction between Ni(II) ion and benzyl dioxime in micellar media in the presence of sodium dodecyl sulfate (SDS). The absorbance is linear from 0.1 up to 25.0 μg mL -1 in aqueous solution with repeatability (RSD) of 1.0% at a concentration of 1 μg mL -1 and a detection limit of 0.12 ng mL -1 and molar absorption coefficient of 68,600 L mol -1 cm -1. The influence of reaction variables including type and amount of surfactant, pH, and amount of ligand and complexation time and the effect of interfering ions are investigated. The proposed procedure was applied to the determination of trace amounts of Ni(II) ion in tap water, river water, chocolate and vegetable without separation or organic solvent extraction.

Does Time-on-Task Estimation Matter? Implications for the Validity of Learning Analytics Findings

ERIC Educational Resources Information Center

Kovanovic, Vitomir; Gaševic, Dragan; Dawson, Shane; Joksimovic, Srecko; Baker, Ryan S.; Hatala, Marek

2015-01-01

With\twidespread adoption of Learning Management Systems (LMS) and other learning technology, large amounts of data--commonly known as trace data--are readily accessible to researchers. Trace data has been extensively used to calculate time that students spend on different learning activities--typically referred to as time-on-task. These measures…

Absorption and distribution of lycopene in rat colon.

PubMed

Oshima, S; Inakuma, T; Narisawa, T

1999-01-01

Colonic absorption and distribution of lycopene, which inhibited rat colon carcinogenesis in our previous studies, were investigated in Sprague-Dawley rats. Three groups of six rats each with or without a single-barreled colostomy at the mid colon were given a single intragastric or intracolonic dose of 0.2 mL of corn oil containing 12 mg of lycopene. Twenty-four hours later, all rats were sacrificed and the blood and some tissues were collected. The contents of lycopene in the samples were assayed by HPLC. Lycopene was detected in an appreciable amount in the liver, but only in trace amount in the serum of all rats treated with an intracolonic dose of lycopene and in rats with an intragastric dose. After an intragastric lycopene treatment, lycopene was detected in the mucosa of the proximal colon and of the distal colon of the colostomized rats, whose distal colon had been excluded from the fecal stream. A large amount of lycopene was recovered in the feces. None was detected in any sample from the control rats treated with an intragastric or intracolonic dose of plain corn oil. The results suggest that lycopene is absorbed from the colon and also from the small intestine. It might be concluded that both ways of absorption contribute to a comparative amount of lycopene accumulation in the colon mucosa after ingestion of this carotenoid.

Sol-Gel Synthesis of Ordered β-Cyclodextrin-Containing Silicas

NASA Astrophysics Data System (ADS)

Trofymchuk, Iryna Mykolaivna; Roik, Nadiia; Belyakova, Lyudmila

2016-03-01

New approaches for β-cyclodextrin-containing silicas synthesis were demonstrated. Materials with hexagonally ordered mesoporous structure were prepared by postsynthesis grafting and by co-condensation methods. β-Cyclodextrin activated by a N, N'-carbonyldiimidazole was employed for postsynthesis treatment of 3-aminopropyl-modified MCM-41 support as well as for sol-gel synthesis with β-cyclodextrin-containing organosilane and tetraethyl orthosilicate participation in the presence of cetyltrimethylammonium bromide. The successful incorporation of cyclic oligosaccharide moieties in silica surface layer was verified by means of FT-IR spectroscopy and chemical analysis. Obtained β-cyclodextrin-containing materials were characterized by X-ray diffraction, transmission electron microscopy, and low-temperature adsorption-desorption of nitrogen. In spite of commensurable loading of β-cyclodextrin groups attained by both proposed approaches (up to 0.028 μmol · m-2), it was found that co-condensation procedure provides uniform distribution of β-cyclodextrin functionalities in silica framework, whereas postsynthesis grafting results in modification of external surface of silica surface. Adsorption of benzene from aqueous solutions onto the surface of β-cyclodextrin-containing materials prepared by co-condensation method was studied as the function of time and equilibrium concentration. Langmuir and Freundlich models were used to evaluate adsorption processes and parameters. Adsorption experiments showed that β-cyclodextrin-containing silicas could be promising for the trace amount removal of aromatics from water.

Application of SERS spectroscopy for detection of trace components in urinary deposits

NASA Astrophysics Data System (ADS)

Pucetaite, Milda; Velicka, Martynas; Tamosaityte, Sandra; Sablinskas, Valdas

2014-03-01

Surface-enhanced Raman scattering (SERS) spectroscopy can be a useful tool in regard to disease diagnosis and prevention. Advantage of SERS over conventional Raman spectroscopy is its significantly increased signal (up to factor of 106-108) which allows detection of trace amounts of substances in the sample. So far, this technique is successfully used for analysis of food, pieces of art and various biochemical/biomedical samples. In this work, we survey the possibility of applying SERS spectroscopy for detection of trace components in urinary deposits. Early discovery together with the identification of the exact chemical composition of urinary sediments could be crucial for taking appropriate preventive measures that inhibit kidney stone formation or growth processes. In this initial study, SERS spectra (excitation wavelength - 1064 nm) of main components of urinary deposits (calcium oxalate, uric acid, cystine, etc.) were recorded by using silver (Ag) colloid. Spectra of 10-3-10-5 M solutions were obtained. While no/small Raman signal was detected without the Ag colloid, characteristic peaks of the substances could be clearly separated in the SERS spectra. This suggests that even small amounts of the components could be detected and taken into account while determining the type of kidney stone forming in the urinary system. We found for the first time that trace amounts of components constituting urinary deposits could be detected by SERS spectroscopy. In the future study, the analysis of centrifuged urine samples will be carried out.

Gastropod growth and survival as bioindicators of stress associated with high nutrients in the intertidal of a shallow temperate estuary

NASA Astrophysics Data System (ADS)

Marsden, Islay D.; Baharuddin, Nursalwa

2015-04-01

The effects of multiple stressors on estuarine organisms are not well understood. Using cage experiments we measured the survival and growth of the pulmonate gastropod Amphibola crenata at five locations which differed contaminant levels. Water nutrients came from a nearby sewage treatment works and the sediment contained low levels of trace metals. Over 6 weeks of exposure, sediment surface chlorophyll levels varied amongst locations. The Chl a values were positively correlated with sediment N and P and trace metals As, Cd, Cu, Pb and Zn. Pulmonate survival depended on location, highest mortality was from a site close to the treatment plant and mortality rate of large individuals decreased significantly with distance away from it. For four locations, medium A. crenata had higher survival than small (juveniles) or adults. Growth rates of small individuals exceeded those for medium and large A. crenata. The mean length increment/week for medium gastropods ranged between 0.49 and 1.11 mm and was negatively correlated with the amount of Chl a in the surface sediment, suggesting the negative effects of eutrophication on gastropod growth. Growth rate of the pulmonate was not correlated with nutrient concentration or trace metal concentrations in the sediment. The dry weight condition index (CI) did not correlate with the growth rate, and for medium individuals, was unaffected by any of the environmental variables. The CI of small individuals was negatively affected by increasing water nutrient levels and the CI of large individuals negatively affected by increasing sediment nutrients and trace metal concentrations. The results from this study suggest that gastropod growth and survival could be used as tools to monitor the effects of changing nutrient levels and recovery from eutrophication within temperate estuaries.

Geological and geochemical studies in the Wadi Bidah District, Kingdom of Saudi Arabia

USGS Publications Warehouse

Smith, C.W.; Waters, B.C.; Naqvi, M.; Worl, R.G.; Helaby, A.M.; Flanigan, V.J.; Sadek, H.S.; Samater, R.M.

1983-01-01

Geological and geochemical followup studies of airborne electromagnetic anomalies in the Wadi Bidah district, southwestern Saudi Arabia, did not reveal metals of economic grade. Investigation of an anomaly enclosing the Rabathan ancient mine disclosed tightly folded and sheared Proterozoic tuffaceous rocks interlayered mostly with chert, dolomite, carbonaceous rocks, and volcanic wacke including cherty iron-manganese formations slightly anomalous in copper and zinc. Three drill holes placed to test anomalies within these formations yielded negative results. Studies of a long, narrow anomaly north of the Rabathan area indicated a similar geological environment. This northern area also contains limited zones that are highly anomalous in copper and zinc and extensive zones that are slightly anomalous in those metals. Drilling was not undertaken in this area. The Bilajimah airborne electromagnetic anomaly west of Wadi Bidah coincides with a broad synclinorium of layered felsic turfs and gossans. Geochemical studies indicated slightly anomalous copper, zinc, and silver values in gossans within the anomaly area. Two drill holes intersected carbonaceous rock that contained approximately 15 percent pyrrhotite and traces of sphalerite and chalcopyrite. Two geophysically anomalous areas west of Wadi Bidah surround ancient mines at Mahawiyah and Khayal al Masna'ah. Results of geochemical sampling at these workings were positive. An airborne electromagnetic anomaly located in the Assifar area in the southwestern corner of the Wadi Bidah district is underlain principally by metasedimentary rocks that include large linear zones of cherty iron-manganese formation and a few gossans .containing secondary base metal minerals. Detailed mapping and sampling of the Mulhal ancient mine, located west of Wadi Bidah, revealed two types of polymetallic gossans : (1) stratiform deposits interlayered with ignimbrites and mafic volcanic rocks and (2) barite-bearing gossanous material in shear zones that grade into hydrothermally altered shear zones and extend beyond the mine area. The gossans and gossanous shear zones contain anomalous amounts of gold, silver, lead, copper, zinc, barium, and selenium. Two gossans west of Wadi Bidah were mapped and sampled in detail; both gossans are interlayered, with siliceous volcanic rocks. Although the gossan at Jabal Mohr covers a large area, it contains low amounts of precious and base metals. The gossan at Mulhal No. 2 contains moderate to high amounts of gold, silver, copper, lead, and zinc.

Development of a selective and pH-independent method for the analysis of ultra trace amounts of nitrite in environmental water samples after dispersive magnetic solid phase extraction by spectrofluorimetry.

PubMed

Daneshvar Tarigh, Ghazale; Shemirani, Farzaneh

2014-10-01

This paper describes an innovative and rapidly dispersive magnetic solid phase extraction spectrofluorimetry (DMSPE-FL) method for the analysis of trace amounts of nitrite in some environmental water samples. The method includes derivatization of aqueous nitrite with 2, 3-diaminonaphthalene (DAN), analysis of highly fluorescent 2, 3-naphthotriazole (NAT) derivative using spectrofluorimetry after DSPME. The novelty of our method is based on forming NAT that was independent with the pH-responsive and was adsorbed on MMWCNT by hydrophobic attractions in both acidic and basic media. The extraction efficiency of the sorbent was investigated by extraction of nitrite. The optimum extraction conditions for NO2(-) were obtained as of extraction time, 1.5 min; 10mg sorbent from 160 mL of the sample solution, and elution with 1 mL of acetone/KOH. Under the optimal conditions, the calibration curves were obtained in the range of 0.1-80 µg L(-1) (R(2)=0.999) and LOD (S/N=3) was obtained in 34 ng L(-1). Relative standard deviations (RSD) were 0.6 % (five replicates at 5 μg L(-1)). In addition, the feasibility of the method was demonstrated with extraction and determination of nitrite from some real samples containing tap, mineral, sea, rain, snow and ground waters, with the recovery in standard addition to real matrix of 94-102 % and RSDs of 1.8-10.6%. Copyright © 2014 Elsevier B.V. All rights reserved.

Trace elements in a commercial freeze-dried human urine reference material.

PubMed

Veillon, C; Patterson, K Y

1996-07-01

A large batch of freeze-dried human urine reference material, Seronorm Trace Elements Urine, Lot 101021, was prepared commercially (Nycomed Pharma AS, Oslo, Norway) for quality control purposes in trace element analysis. Analytes are being determined by a voluntary, international co-operative effort so that the material will be available to the scientific community at modest cost. The material is in stoppered glass vials and is to be reconstituted with 5.00 ml of water prior to use. We have evaluated the trace element content for several elements, including chromium and zinc, elements for which we have two independent methods available for the determinations, namely isotope dilution mass spectrometry (IDMS) and atomic absorption spectrometry (AAS). We also report on other trace elements measured by IDMS alone, such as Se, for which we have enriched stable isotopes available. Results for chromium indicate a mean +/- standard deviation (n = 10) of 1.2 +/- 0.3 (by IDMS) and 1.4 +/- 0.3 (by AAS) ng Cr per ml of reconstituted urine, indicating possible inhomogeneity and/or contamination (21-25% relative standard deviation, RSD). Approximately half of the observed chromium originates from the sample container. The values observed for zinc were 590 +/- 90 ng ml-1 (15% RSD) for freshly reconstituted material, 760 +/- 60 ng ml-1 (8% RSD) for material reconstituted 4 d earlier, and 940 +/- 60 ng ml-1 (6% RSD) 2 months after reconstitution. Selenium values by IDMS were very reproducible, with a mean concentration of 16 +/- 0.15 ng g-1 (0.9% RSD), suggesting little or no contamination and a high degree of sample homogeneity for this element. The source of potential contaminants has been evaluated by multielement determinations of leachates of the vials and stoppers. Elements noted in significant amounts include B, Ba, Sr, Mo, Cu and Zn, with most of the zinc coming from the rubber stopper.

Antimicrobial activity of alcohols from Musca domestica.

PubMed

Gołębiowski, Marek; Dawgul, Małgorzata; Kamysz, Wojciech; Boguś, Mieczysława I; Wieloch, Wioletta; Włóka, Emilia; Paszkiewicz, Monika; Przybysz, Elżbieta; Stepnowski, Piotr

2012-10-01

Information on the stimulatory and inhibitory effects of cuticular alcohols on growth and virulence of insecticidal fungi is unavailable. Therefore, we set out to describe the content of cuticular and internal alcohols in the body of housefly larvae, pupae, males and females. The total cuticular alcohols in larvae, males and females of Musca domestica were detected in comparable amounts (4.59, 3.95 and 4.03 μg g(-1) insect body, respectively), but occurred in smaller quantities in pupae (2.16 μg g(-1)). The major free alcohol in M. domestica larvae was C(12:0) (70.4%). Internal alcohols of M. domestica larvae were not found. Among cuticular pupae alcohols, C(12:0) (31.0%) was the most abundant. In the internal lipids of pupae, only five alcohols were identified in trace amounts. The most abundant alcohol in males was C(24:0) (57.5%). The percentage content of cuticular C(24:0) in males and females (57.5 and 36.5%, respectively) was significantly higher than that of cuticular lipids in larvae and pupae (0.9 and 5.6%, respectively). Only two alcohols were present in the internal lipids of males in trace amounts (C(18:0) and C(20:0)). The most abundant cuticular alcohols in females were C(24:0) (36.5%) and C(12:0) (26.8%); only two alcohols (C(18:0) and C(20:0)) were detected in comparable amounts in internal lipids (3.61±0.32 and 5.01±0.42 μg g(-1), respectively). For isolated alcohols, antimicrobial activity against 10 reference strains of bacteria and fungi was determined. Individual alcohols showed approximately equal activity against fungal strains. C(14:0) was effective against gram-positive bacteria, whereas gram-negative bacteria were resistant to all tested alcohols. Mixtures of alcohols found in cuticular lipids of larvae, pupae, males and females of M. domestica generally presented higher antimicrobial activity than individual alcohols. In contrast, crude extracts containing both cuticular and internal lipids showed no antifungal activity against the entomopathogenic fungus Conidiobolus coronatus, which efficiently kills adult house flies.

Characterization of feed coal and coal combustion products from power plants in Indiana and Kentucky

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

Brownfield, M.E.; Affolter, R.H.; Cathcart, J.D.

1999-07-01

The US Geological Survey, Kentucky Geological Survey, and the University of Kentucky Center for Applied Energy Research are collaborating with Indiana and Kentucky utilities to determine the physical and chemical properties of feed coal and coal combustion products (CCP) from three coal-fired power plants. These three plants are designated as Units K1, K2, and I1 and burn high-, moderate-, and low-sulfur coals, respectively. Over 200 samples of feed coal and CCP were analyzed by various chemical and mineralogical methods to determine mode of occurrence and distribution of trace elements in the CCP. Generally, feed coals from all 3 Units containmore » mostly well-crystallized kaolinite and quartz. Comparatively, Unit K1 feed coals have higher amounts of carbonates, pyrite and sphalerite. Unit K2 feed coals contain higher kaolinite and illite/muscovite when compared to Unit K1 coals. Unit I1 feed coals contain beta-form quartz and alumino-phosphates with minor amounts of calcite, micas, anatase, and zircon when compared to K1 and K2 feed coals. Mineralogy of feed coals indicate that the coal sources for Units K1 and K2 are highly variable, with Unit K1 displaying the greatest mineralogic variability; Unit I1 feed coal however, displayed little mineralogic variation supporting a single source. Similarly, element contents of Units K1 and K2 feed coals show more variability than those of Unit I1. Fly ash samples from Units K1 and K2 consist mostly of glass, mullite, quartz, and spines group minerals. Minor amounts of illite/muscovite, sulfates, hematite, and corundum are also present. Spinel group minerals identified include magnetite, franklinite, magnesioferrite, trevorite, jacobisite, and zincochromite. Scanning Electron Microscope analysis reveals that most of the spinel minerals are dendritic intergrowths within aluminum silicate glass. Unit I1 fly ash samples contain glass, quartz, perovskite, lime, gehlenite, and apatite with minor amounts of periclase, anhydrite, carbonates, pyroxenes, and spinels. The abundant Ca mineral phases in the Unit I1 fly ashes are attributed to the presence of carbonate, clay and phosphate minerals in the coal.« less

On the Information Content of Program Traces

NASA Technical Reports Server (NTRS)

Frumkin, Michael; Hood, Robert; Yan, Jerry; Saini, Subhash (Technical Monitor)

1998-01-01

Program traces are used for analysis of program performance, memory utilization, and communications as well as for program debugging. The trace contains records of execution events generated by monitoring units inserted into the program. The trace size limits the resolution of execution events and restricts the user's ability to analyze the program execution. We present a study of the information content of program traces and develop a coding scheme which reduces the trace size to the limit given by the trace entropy. We apply the coding to the traces of AIMS instrumented programs executed on the IBM SPA and the SCSI Power Challenge and compare it with other coding methods. Our technique shows size of the trace can be reduced by more than a factor of 5.

Proton-transfer reaction mass spectrometry (PTRMS) in combination with thermal desorption (TD) for sensitive off-line analysis of volatiles.

PubMed

Crespo, Elena; Devasena, Samudrala; Sikkens, Cor; Centeno, Raymund; Cristescu, Simona M; Harren, Frans J M

2012-04-30

When performing trace gas analysis, it is not always possible to bring the source of volatiles and the gas analyzer together. In these cases, volatile storage containers, such as thermal desorption (TD) tubes, can be used for off-line measurement. TD is routinely combined with gas chromatography/mass spectrometry (GC/MS), but so far not with proton-transfer reaction mass spectrometry (PTRMS), which has a faster response. A PTR-quadrupole-MS instrument and a PTR-ion-trap-MS instrument were separately coupled to a TD unit for off-line analysis of trace volatiles in air. Carbograph 1TD/Carbopack X sorbent tubes were filled with different concentrations of a trace gas mixture containing low molecular weight volatiles (32 g/mol up to 136 g/mol) and measured with the above-mentioned combinations. The carrier gas in the TD unit was changed from helium to nitrogen to be able to combine this instrument with the mass spectrometer. Good linearity and reproducibility with the amount of gas stored were obtained. The storage capacity over time (up to 14 days) showed larger variability (<11% for all compounds, except for acetone 27%). Several tubes were filled with breath of different persons, and the breath of a smoker showed increased levels of acetonitrile and benzene. The combination of the PTR ion-trap instrument with the TD unit was also investigated. Due to its higher sampling rate, the ion-trap system showed higher throughput capabilities than the quadrupole system. The combination of TD with PTRMS using both a quadrupole and an ion trap for off-line volatile analysis has been validated. TD tubes can be a robust and compact volatile storage method when the mass spectrometry and the sampling cannot be performed in the same place, for example in large screening studies. In addition, a higher measurement throughput than with GC/MS could be obtained. Copyright © 2012 John Wiley & Sons, Ltd.

[Pigments of green sulfur bacteria isolated from reservoirs of Iavoriv sulfur deposit].

PubMed

Baran, I M; Hudz', S P; Hnatush, S O; Fedorovych, A M

2004-01-01

The enormous amount of hydrogen sulfide (up to 11 mg/ml) is present in the Yavoriv sulfur deposit reservoirs owing to sulfur reductive bacteria activity. As a consequence the ecological situation is badly affected and requires recovering. The biological H2S decomposition by photosynthetic sulfur bacteria, which use the hydrogen sulfide as electron donor during photosynthesis, can be one of the possible ways of this toxic substance destruction. The qualitative and quantitative analysis of photosynthetic pigments composition that derived from green photosynthesizing sulfur bacteria from reservoirs of Yavoriv sulfur deposit is carried out. It was fixed that Pelodictyon sp., Chlorobium sp. and isolated consortia "Pelochromatium sp." contain the bacteriochlorophyll c and d. All the isolated cultures contained bacteriochlorophyll a in trace amounts. The obtained photosynthetic pigments (bacteriochlorophylls, carotenoids) were recognized by their absorption spectra in the visible and far-red region and by their quantity. The difference was not essential. All investigated cultures of isolated bacteria contain some carotenoid the Chlorobium sp. and obtained consortia possesses isorenieratene. The absorption maxima of extracted pigments from young cultures of isolated green sulfur bacteria are more definitely displayed than those from old cultures. Investigations of phototrophic sulfur bacteria were carried out in Ukraine up to now. Ecological problem that occurred in the Yavoriv sulfur deposit as a result of the deposit exploitation caused a necessity of the investigation of photosynthetic sulfur bacteria and bacterial photosynthesis mechanism. The photosynthetic pigments nature identification will promote the fast and precise identification of the new forms of photosynthetic sulfur bacteria and will extend our knowledge about their role in the anoxygenic photosynthesis.

Study of leaching mechanisms of caesium ions incorporated in Ordinary Portland Cement.

PubMed

Papadokostaki, Kyriaki G; Savidou, Anastasia

2009-11-15

In this work, a study of the leaching kinetics of Cs(+) ions from cement paste solids, containing inactive Cs(2)SO(4), is presented, involving (i) the parallel performance of leaching experiments at two temperatures (30 degrees C and 70 degrees C); (ii) the performance of leaching tests with intermediate changes in temperature between 30 degrees C and 70 degrees C; (iii) the use of specimens of two different thicknesses and (iv) the determination of the distribution of Cs(+) in the cement specimen at various stages of the leaching test. The results of leaching studies at 30 degrees C with cement solids simulating the composition of real radioactive wastes, containing NaNO(3), small amounts of inactive CsNO(3) and traces of (137)Cs(+) are also reported. Concentration profiles of Cs(+) in inactive specimens showed that part of the Cs(+) (20-30%) tends to be immobilized in the matrix, while elution of the readily leachable portion follows Fick's law reasonably well. No immobilized Cs(+) was detected in the samples containing considerable amounts of NaNO(3). Long-term leaching experiments (up to 8 years) revealed acceleration of the elution process (not detectable in short-term tests), attributable to increase in porosity caused by erosion of the cement matrix. Sorption experiments of Cs(+) ions by cement granules indicated that adsorption on cement pore surfaces is not significant. On the other hand, the leaching tests at two different temperatures or with intermediate changes in temperature between 30 degrees C and 70 degrees C, yielded activation energies that indicated a more complicated kinetic behavior.

Modified Eddington-inspired-Born-Infeld gravity with a trace term

DOE PAGES

Chen, Che -Yu; Bouhmadi-Lopez, Mariam; Chen, Pisin

2016-01-22

In this study, a modified Eddington-inspired-Born-Infeld (EiBI) theory with a pure trace term g μνR being added to the determinantal action is analysed from a cosmological point of view. It corresponds to the most general action constructed from a rank two tensor that contains up to first order terms in curvature. This term can equally be seen as a conformal factor multiplying the metric g μν . This very interesting type of amendment has not been considered within the Palatini formalism despite the large amount of works on the Born-Infeld-inspired theory of gravity. This model can provide smooth bouncing solutionsmore » which were not allowed in the EiBI model for the same EiBI coupling. Most interestingly, for a radiation filled universe there are some regions of the parameter space that can naturally lead to a de Sitter inflationary stage without the need of any exotic matter field. Finally, in this model we discover a new type of cosmic “quasi-sudden” singularity, where the cosmic time derivative of the Hubble rate becomes very large but finite at a finite cosmic time.« less

Determination of trace elements and their concentrations in clay balls: problem of geophagia practice in Ghana.

PubMed

Arhin, Emmanuel; Zango, Musah S

2017-02-01

Ten samples of 100 g weight were subsampled from 1400 g of the clay balls from which the contained trace element levels were determined by X-ray fluorescence technique. The results of trace elements in the clay balls were calibrated using certified reference materials "MAJMON" and "BH-1." The results showed elevated concentrations but with different concentration levels in the regions, particularly with arsenic, chromium, cobalt, Cs, Zr and La. These trace elements contained in the clay balls are known to be hazardous to human health. Thence the relatively high concentrations of these listed trace elements in clay balls in the three regions, namely Ashanti, Upper East and Volta, which are widely sold in markets in Ghana, could present negative health impact on consumers if consumed at 70 g per day or more and on regular basis. On the basis of these, the study concludes an investigation to establish breakeven range for trace element concentrations in the clay balls as it has been able to demonstrate the uneven and elevated values in them. The standardized safe ranges of trace elements will make the practice safer for the people that ingest clay balls in Ghana.

Electrostatic precipitator performance and trace element emissions from two Kraft recovery boilers.

PubMed

Lind, Terttaliisa; Hokkinen, Jouni; Jokiniemi, Jorma K; Hillamo, Risto; Makkonen, Ulla; Raukola, Antti; Rintanen, Jaakko; Saviharju, Kari

2006-01-15

Fine particle emissions from combustion sources have gained attention recently due to their adverse effects on human health. The emission depends on the combustion process, fuel, and particulate removal technology. Particle concentrations at Kraft recovery boiler exits are very high, and the boilers are typically equipped with electrostatic precipitators (ESP). However, little data are available on the ESP performance in recovery boilers. Particle concentrations and size distributions were determined at two modern, operating recovery boilers. In addition, we determined the fractional collection efficiency of the ESPs by simultaneous measurements at the ESP inlet and outlet and the particulate emissions of trace metals. The particle mass concentration atthe ESP inlet was 11-24 g/Nm3 at the two boilers. Particle emissions were 30-40 mg/ Nm3 at boiler A and 12-15 mg/Nm3 at boiler B. The particle size distributions had a major particle mode at around 1 microm. These fume particles contained most of the particle mass. The main components in the particles were sodium and sulfate with minor amounts of chloride, potassium, and presumably some carbonate. The ESP collection efficiency was 99.6-99.8% at boiler A and 99.9% at boiler B. The particle penetration through the ESP was below 0.6% in the entire fume particle size range of 0.3-3 microm. Trace element emissions from both boilers were well below the limit values set by EU directive for waste incineration.

Trace-fiber color discrimination by electrospray ionization mass spectrometry: a tool for the analysis of dyes extracted from submillimeter nylon fibers.

PubMed

Tuinman, Albert A; Lewis, Linda A; Lewis, Samuel A

2003-06-01

The application of electrospray ionization mass spectrometry (ESI-MS) to trace-fiber color analysis is explored using acidic dyes commonly employed to color nylon-based fibers, as well as extracts from dyed nylon fibers. Qualitative information about constituent dyes and quantitative information about the relative amounts of those dyes present on a single fiber become readily available using this technique. Sample requirements for establishing the color identity of different samples (i.e., comparative trace-fiber analysis) are shown to be submillimeter. Absolute verification of dye mixture identity (beyond the comparison of molecular weights derived from ESI-MS) can be obtained by expanding the technique to include tandem mass spectrometry (ESI-MS/MS). For dyes of unknown origin, the ESI-MS/MS analyses may offer insights into the chemical structure of the compound-information not available from chromatographic techniques alone. This research demonstrates that ESI-MS is viable as a sensitive technique for distinguishing dye constituents extracted from a minute amount of trace-fiber evidence. A protocol is suggested to establish/refute the proposition that two fibers--one of which is available in minute quantity only--are of the same origin.

Evidence for magma mixing within the Laacher See magma chamber (East Eifel, Germany)

USGS Publications Warehouse

Worner, G.; Wright, T.L.

1984-01-01

The final pyroclastic products of the late Quaternary phonolitic Laacher See volcano (East Eifel, W.-Germany) range from feldspar-rich gray phonolite to dark olivine-bearing rocks with variable amounts of feldspar and Al-augite megacrysts. Petrographically and chemically homogeneous clasts occur along with composite lapilli spanning the compositional range from phonolite (MgO 0.9%) to mafic hybrid rock (MgO 7.0%) for all major and trace elements. Both a basanitic and a phonolitic phenocryst paragenesis occur within individual clasts. The phonolite-derived phenocrysts are characterized by glass inclusions of evolved composition, rare inverse zoning and strong resorption indicating disequilibrium with the mafic hybrid matrix. Basanitic (magnesian) clinopyroxene and olivine, in contrast, show skeletal (normally zoned) overgrowths indicative of post-mixing crystallization. In accord with petrographical and other chemical evidence, mass balance calculations suggest mixing of an evolved Laacher See phonolite containing variable amounts of mineral cumulates and a megacryst-bearing basanite magma. Magma mixing occurred just prior to eruption (hours) of the lowermost magma layer of the Laacher See magma chamber but did not trigger the volcanic activity. ?? 1984.

Morphology, composition, and mixing state of primary particles from combustion sources - crop residue, wood, and solid waste.

PubMed

Liu, Lei; Kong, Shaofei; Zhang, Yinxiao; Wang, Yuanyuan; Xu, Liang; Yan, Qin; Lingaswamy, A P; Shi, Zongbo; Lv, Senlin; Niu, Hongya; Shao, Longyi; Hu, Min; Zhang, Daizhou; Chen, Jianmin; Zhang, Xiaoye; Li, Weijun

2017-07-11

Morphology, composition, and mixing state of individual particles emitted from crop residue, wood, and solid waste combustion in a residential stove were analyzed using transmission electron microscopy (TEM). Our study showed that particles from crop residue and apple wood combustion were mainly organic matter (OM) in smoldering phase, whereas soot-OM internally mixed with K in flaming phase. Wild grass combustion in flaming phase released some Cl-rich-OM/soot particles and cardboard combustion released OM and S-rich particles. Interestingly, particles from hardwood (pear wood and bamboo) and softwood (cypress and pine wood) combustion were mainly soot and OM in the flaming phase, respectively. The combustion of foam boxes, rubber tires, and plastic bottles/bags in the flaming phase released large amounts of soot internally mixed with a small amount of OM, whereas the combustion of printed circuit boards and copper-core cables emitted large amounts of OM with Br-rich inclusions. In addition, the printed circuit board combustion released toxic metals containing Pb, Zn, Sn, and Sb. The results are important to document properties of primary particles from combustion sources, which can be used to trace the sources of ambient particles and to know their potential impacts in human health and radiative forcing in the air.

CAD-based stand-alone spacecraft radiation exposure analysis system: An application of the early man-tended Space Station

NASA Technical Reports Server (NTRS)

Appleby, M. H.; Golightly, M. J.; Hardy, A. C.

1993-01-01

Major improvements have been completed in the approach to analyses and simulation of spacecraft radiation shielding and exposure. A computer-aided design (CAD)-based system has been developed for determining the amount of shielding provided by a spacecraft and simulating transmission of an incident radiation environment to any point within or external to the vehicle. Shielding analysis is performed using a customized ray-tracing subroutine contained within a standard engineering modeling software package. This improved shielding analysis technique has been used in several vehicle design programs such as a Mars transfer habitat, pressurized lunar rover, and the redesigned international Space Station. Results of analysis performed for the Space Station astronaut exposure assessment are provided to demonastrate the applicability and versatility of the system.

Fullerenes in Allende Meteorite

NASA Technical Reports Server (NTRS)

Becker, L.; Bada, J. L.; Winans, R. E.; Bunch, T. E.

1994-01-01

The detection of fullerenes in deposits from meteor impacts has led to renewed interest in the possibility that fullerenes are present in meteorites. Although fullerenes have not previously been detected in the Murchison and Allende meteorites, the Allende meteorite is known to contain several well-ordered graphite particles which are remarkably similar in size and appearance to the fullerene-related structures carbon onions and nanotubes. We report that fullerenes are in fact present in trace amounts in the Allende meteorite. In addition to fullerenes, we detected many polycyclic aromatic hydrocarbons (PAHs) in the Allende meteorite, consistent with previous reports. In particular, we detected benzofluoranthene and corannulene (C20H10), five-membered ring structures which have been proposed as precursors to the formation of fullerene synthesis, perhaps within circumstellar envelopes or other sites in the interstellar medium.

Microgravimetric Analysis Method for Activation-Energy Extraction from Trace-Amount Molecule Adsorption.

PubMed

Xu, Pengcheng; Yu, Haitao; Li, Xinxin

2016-05-03

Activation-energy (Ea) value for trace-amount adsorption of gas molecules on material is rapidly and inexpensively obtained, for the first time, from a microgravimetric analysis experiment. With the material loaded, a resonant microcantilever is used to record in real time the adsorption process at two temperatures. The kinetic parameter Ea is thereby extracted by solving the Arrhenius equation. As an example, two CO2 capture nanomaterials are examined by the Ea extracting method for evaluation/optimization and, thereby, demonstrating the applicability of the microgravimetric analysis method. The achievement helps to solve the absence in rapid quantitative characterization of sorption kinetics and opens a new route to investigate molecule adsorption processes and materials.

Reactivation of the chloroplast CF1-ATPase beta subunit by trace amounts of the CF1 alpha subunit suggests a chaperonin-like activity for CF1 alpha.

PubMed

Avni, A; Avital, S; Gromet-Elhanan, Z

1991-04-25

Incubation of tobacco and lettuce thylakoids with 2 M LiCl in the presence of MgATP removes the beta subunit from their CF1-ATPase (CF1 beta) together with varying amounts of the CF1 alpha subunit (CF1 alpha). These 2 M LiCl extracts, as with the one obtained from spinach thylakoids (Avital, S., and Gromet-Elhanan, Z. (1991) J. Biol. Chem. 266, 7067-7072), could form active hybrid ATPases when reconstituted into inactive beta-less Rhodospirillum rubrum chromatophores. Pure CF1 beta fractions that have been isolated from these extracts could not form such active hybrids by themselves, but could do so when supplemented with trace amounts (less than 5%) of CF1 alpha. A mitochondrial F1-ATPase alpha subunit was recently reported to be a heat-shock protein, having two amino acid sequences that show a highly conserved identity with sequences found in molecular chaperones (Luis, A. M., Alconada, A., and Cuezva, J. M. (1990) J. Biol. Chem. 265, 7713-7716). These sequences are also conserved in CF1 alpha isolated from various plants, but not in F1 beta subunits. The above described reactivation of CF1 beta by trace amounts of CF1 alpha could thus be due to a chaperonin-like function of CF1 alpha, which involves the correct, active folding of isolated pure CF1 beta.

Toxicological and chemical screening of Antarctica sediments: Use of whole sediment toxicity tests, microtox, mutatox and semipermeable membrane devices (SPMDs)

USGS Publications Warehouse

Cleveland, Laverne; Little, Edward E.; Petty, Jimmie D.; Johnson, B. Thomas; Lebo, Jon A.; Orazio, Carl E.; Dionne, Jane

1997-01-01

Eight whole sediment samples from Antarctica (four from Winter Quarters Bay and four from McMurdo Sound) were toxicologically and chemically evaluated. Also, the influence of ultraviolet radiation on the toxicity and bioavailability of contaminants associated with the sediment samples was assessed. The evaluations were accomplished by use of a 10-day whole sediment test with Leptocheirus plumulosus, Microtox®, Mutatox® and semipermeable membrane devices (SPMDs). Winter Quarters Bay sediments contained about 250 ng g−1 (dry weight) total PCBs and 20 μg g−1 total PAHs. These sediments elicited toxicity in the Microtox test and avoidance and inhibited burrowing in the L. plumulosus test. The McMurdo Sound sediment samples contained only trace amounts of PCBs and no PAHs, and were less toxic in both the L. plumulosus and Microtox tests compared to the Winter Quarters Bay sediments. The sediments from McMurdo Sound apparently contained some unidentified substance which was photolytically modified to a more toxic form. The photolytic modification of sediment-associated contaminants, coupled with the polar ozone hole and increased incidence of ultraviolet radiation could significantly increase hazards to Antarctic marine life.

Metal concentrations in cosmetics commonly used in Nigeria.

PubMed

Orisakwe, Orish Ebere; Otaraku, Jonathan Oye

2013-01-01

Trace amounts of potentially toxic metals can be either intentionally added to cosmetics or present as impurities in the raw materials. In the present study, the levels of lead, cadmium, nickel, chromium, and mercury have been assessed in 28 body creams and lotions, 10 powders, 3 soaps, 5 eye make-ups, and 4 lipsticks widely available on Nigerian markets. The increases over suggested or mandated levels of lead in these creams and lotions ranged from 6.1 to 45.9 and from 1.2 to 9.2 mg kg⁻¹ when compared with Cosmetic Ingredients Review Expert Panel 2007 and German safe maximum permissible limit of lead in cosmetics, respectively. About 61% of the body cosmetics, the lotions, and the creams contained detectable levels of nickel ranging from 1.1 to 6.4-9.2 mg kg⁻¹. Chromium and mercury were undetected in 100% of the cosmetic product. Taken together, lead and cadmium were high in creams and lotions. Most of the imported creams and creamy white coloured cosmetics contained higher levels of metal contaminants than the other colours. Regulatory Agencies in developing nations should take appropriate action for cosmetics that contain lead and cadmium beyond the reference limits.

Metal Concentrations in Cosmetics Commonly Used in Nigeria

PubMed Central

Orisakwe, Orish Ebere; Otaraku, Jonathan Oye

2013-01-01

Trace amounts of potentially toxic metals can be either intentionally added to cosmetics or present as impurities in the raw materials. In the present study, the levels of lead, cadmium, nickel, chromium, and mercury have been assessed in 28 body creams and lotions, 10 powders, 3 soaps, 5 eye make-ups, and 4 lipsticks widely available on Nigerian markets. The increases over suggested or mandated levels of lead in these creams and lotions ranged from 6.1 to 45.9 and from 1.2 to 9.2 mg kg−1 when compared with Cosmetic Ingredients Review Expert Panel 2007 and German safe maximum permissible limit of lead in cosmetics, respectively. About 61% of the body cosmetics, the lotions, and the creams contained detectable levels of nickel ranging from 1.1 to 6.4–9.2 mg kg−1. Chromium and mercury were undetected in 100% of the cosmetic product. Taken together, lead and cadmium were high in creams and lotions. Most of the imported creams and creamy white coloured cosmetics contained higher levels of metal contaminants than the other colours. Regulatory Agencies in developing nations should take appropriate action for cosmetics that contain lead and cadmium beyond the reference limits. PMID:24385889

Isotope-Labeled Composition B for Tracing Detonation Signatures

NASA Astrophysics Data System (ADS)

Manner, Virginia; Podlesak, David; Huber, Rachel; Amato, Ronald; Giambra, Anna; Bowden, Patrick; Hartline, Ernest; Dattelbaum, Dana

2017-06-01

To better understand how solid carbon forms and evolves during detonation, we have prepared Composition B with 13 C and 15 N-labeled 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) and 2,4,6-trinitrotoluene (TNT) in order to trace the formation of soot from the carbon and nitrogen atoms in these explosives. Isotope-labeling of explosives has been performed in the recent past for a variety of reasons, including environmental remediation and reaction mechanism studies. Because it is expensive and time consuming to prepare these materials, and our detection equipment only requires trace amounts of isotopes, we have prepared fully-labeled materials and substituted them into unlabeled RDX and TNT at less than the 1% level. We will discuss the preparation and full characterization of this labeled Composition B, the detonation tests performed, along with the results of the post-detonation soot analysis. Various detonation models predict differing amounts and forms of carbon and nitrogen; these isotopically-labeled precursors have allowed these models to be tested.

A novel technology for the detection, enrichment, and separation of trace amounts of target DNA based on amino-modified fluorescent magnetic composite nanoparticles.

PubMed

Wang, Guannan; Su, Xingguang

2010-06-01

A novel, highly sensitive technology for the detection, enrichment, and separation of trace amounts of target DNA was developed on the basis of amino-modified fluorescent magnetic composite nanoparticles (AFMN). In this study, the positively charged amino-modified composite nanoparticles conjugate with the negatively charged capture DNA through electrostatic binding. The optimal combination of AFMN and capture DNA was measured by dynamic light scattering (DLS) and UV-vis absorption spectroscopy. The highly sensitive detection of trace amounts of target DNA was achieved through enrichment by means of AFMN. The detection limit for target DNA is 0.4 pM, which could be further improved by using a more powerful magnet. Because of their different melting temperatures, single-base mismatched target DNA could be separated from perfectly complementary target DNA. In addition, the photoluminescence (PL) signals of perfectly complementary target DNA and single-base mismatched DNA as well as the hybridization kinetics of different concentrations of target DNA at different reaction times have also been studied. Most importantly, the detection, enrichment, and separation ability of AFMN was further verified with milk. Simple and satisfactory results were obtained, which show the great potential in the fields of mutation identification and clinical diagnosis.

"Dilute & shoot" approach for rapid determination of trace amounts of nicotine in zero-level e-liquids by reversed phase liquid chromatography and hydrophilic interactions liquid chromatography coupled with tandem mass spectrometry-electrospray ionization.

PubMed

Kubica, Paweł; Kot-Wasik, Agata; Wasik, Andrzej; Namieśnik, Jacek

2013-05-10

Two analytical procedures are proposed where HILIC and RPLC techniques are coupled with tandem mass spectrometry detection for rapid determination of trace amounts of nicotine in zero-level liquids for electronic cigarettes. Samples are prepared on the basis of the approach "dilute & shoot" which makes this important step quick and not complicated. The chromatographic separation was carried out on a Zorbax XDB column (RPLC method) and Ascentis Si column (HILIC mode). Within-run precisions (CVs) measured at three concentration levels were as follows: 0.73%, 0.98% and 1.44% for RPLC method and 1.39%, 1.44% and 0.57% (HILIC mode). Between-run CVs were as follows: 1.94%, 1.02% and 1.22% for RPLC mode and 1.49%, 1.20% and 1.22% for HILIC mode. The detection limits of RPLC and HILIC modes were 4.08 and 3.90 ng/mL respectively. The proposed procedures are rapid, not complicated, sensitive and are suitable for fast determination of trace amounts of nicotine in zero-level liquids for electronic cigarettes. Copyright © 2013 Elsevier B.V. All rights reserved.

Acute Stress Facilitates Trace Eyeblink Conditioning in C57BL/6 Male Mice and Increases the Excitability of Their CA1 Pyramidal Neurons

ERIC Educational Resources Information Center

Weiss, Craig; Sametsky, Evgeny; Sasse, Astrid; Spiess, Joachim; Disterhoft, John F.

2005-01-01

The effects of stress (restraint plus tail shock) on hippocampus-dependent trace eyeblink conditioning and hippocampal excitability were examined in C57BL/6 male mice. The results indicate that the stressor significantly increased the concentration of circulating corticosterone, the amount and rate of learning relative to nonstressed conditioned…

Study of the Effect of Trace Mg Additions on Carbides in Die Steel H13

NASA Astrophysics Data System (ADS)

Li, Ji; Li, Jing; Wang, Liang-liang; Zhu, Qin-tian

2016-09-01

Carbides in annealed steel H13 without magnesium and with a micro-addition of magnesium (0.0010%) are studied. Trace amounts of magnesium strengthen carbide segregation and reduce their size. Carbides phases M7C3, M6 C, and M(C, N) are detected in steel H13, and this agrees with results of thermodynamic calculations.

Measuring Trace Hydrocarbons in Silanes

NASA Technical Reports Server (NTRS)

Lesser, L. A.

1984-01-01

Technique rapid and uses standard analytical equipment. Silane gas containing traces of hydrocarbons injected into carrier gas of moist nitrogen having about 0.2 percent water vapor. Carrier, water and silane pass through short column packed with powdered sodium hydroxide which combines moisture and silane to form nonvolatile sodium silicate. Carrier gas free of silane but containing nonreactive hydrocarbons, pass to silica-gel column where chromatographic separation takes place. Hydrocarbons measured by FID.

Gypsum treated fly ash as a liner for waste disposal facilities

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

Sivapullaiah, Puvvadi V., E-mail: siva@civil.iisc.ernet.in; Baig, M. Arif Ali, E-mail: reach2arif@gmail.com

2011-02-15

Fly ash has potential application in the construction of base liners for waste containment facilities. While most of the fly ashes improve in the strength with curing, the ranges of permeabilities they attain may often not meet the basic requirement of a liner material. An attempt has been made in the present context to reduce the hydraulic conductivity by adding lime content up to 10% to two selected samples of class F fly ashes. The use of gypsum, which is known to accelerate the unconfined compressive strength by increasing the lime reactivity, has been investigated in further improving the hydraulicmore » conductivity. Hydraulic conductivities of the compacted specimens have been determined in the laboratory using the falling head method. It has been observed that the addition of gypsum reduces the hydraulic conductivity of the lime treated fly ashes. The reduction in the hydraulic conductivity of the samples containing gypsum is significantly more for samples with high amounts of lime contents (as high as 1000 times) than those fly ashes with lower amounts of lime. However there is a relatively more increase in the strengths of the samples with the inclusion of gypsum to the fly ashes at lower lime contents. This is due to the fact that excess lime added to fly ash is not effectively converted into pozzolanic compounds. Even the presence of gypsum is observed not to activate these reactions with excess lime. On the other hand the higher amount of lime in the presence of sulphate is observed to produce more cementitious compounds which block the pores in the fly ash. The consequent reduction in the hydraulic conductivity of fly ash would be beneficial in reducing the leachability of trace elements present in the fly ash when used as a base liner.« less

Effects of source of trace minerals and plane of nutrition on growth and health of transported neonatal dairy calves.

PubMed

Osorio, J S; Wallace, R L; Tomlinson, D J; Earleywine, T J; Socha, M T; Drackley, J K

2012-10-01

The aims of the experiment were to evaluate the effects of source of trace minerals (TM) and plane of nutrition (PN) early in life on growth and health of transported calves. Ninety male Holstein calves <1 wk old were assigned to treatments in a 2×2 factorial arrangement of PN and TM source in a randomized complete block design. Calves assigned to low PN (LPN) received milk replacer [22% crude protein (CP), 20% fat, 568 g of powder/d for wk 1 to 4, and 284 g of powder/d for wk 5] plus ad libitum access to starter [18% CP, dry matter (DM) basis, for wk 1 to 12] and a limited amount of hay (0.5 kg/d as fed, for wk 10 to 12); LPN calves were weaned at 6 wk. During wk 13 to 20, LPN calves were fed 3.2 kg/d of grower mix (16% CP, DM basis) plus chopped hay for ad libitum intake. Calves assigned to high PN (HPN) received variable amounts of milk replacer (28% CP; 20% fat; and 810, 1,136, and 568 g of powder/d for wk 1, 2 to 6, and 7, respectively) plus ad libitum access to starter (22% CP, DM basis, wk 1 to 12) and limited hay (0.5 kg/d as fed, for wk 10 to 12); HPN calves were weaned at wk 7. Calves assigned to HPN were offered grower mix for ad libitum intake plus a limited amount of chopped hay (0.5 kg/d, as-fed basis) from wk 13 to 20. Milk replacers were formulated to contain balanced amounts of either inorganic (I) or organic (O) TM (50, 50, 10, and 100mg/kg of Zn, Mn, Cu, and Fe, respectively), whereas respective ITM or OTM starters and growers contained Zn, Mn, Cu, and Co at 70, 55, 12, and 1mg/kg. The HPN treatments increased final body weight and stature measurements, average daily gain, and gain-to-feed ratio through wk 20. Starter intake was lower for calves fed HPN. The OTM increased growth when supplemented to HPN but not when supplemented to LPN. During the liquid-feeding period, fecal scores were more fluid for calves fed HPN but measures of health status did not differ among diets. Results indicated that an enhanced nutritional program during early life allowed calves to have greater overall growth and maintain a normal health status throughout the preweaning period. High PN and OTM were synergistic in increasing early growth of calves. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Turbine Chemistry Modeling

NASA Technical Reports Server (NTRS)

Liu, Nan-Suey; Wey, Thomas

2001-01-01

Many of the engine exhaust species resulting in significant environmental impact exist in trace amounts. Recent research, e.g., conducted at MIT-AM, has pointed to the intra-engine environment as a possible site for important trace chemistry activity. In addition, the key processes affecting the trace species activity occurring downstream in the air passages of the turbine and exhaust nozzle are not well understood. Most recently, an effort has been initiated at NASA Glenn Research Center under the UEET Program to evaluate and further develop CFD-based technology for modeling and simulation of intra-engine trace chemical changes relevant to atmospheric effects of pollutant emissions from aircraft engines. This presentation will describe the current effort conducted at Glenn; some preliminary results relevant to the trace species chemistry in a turbine passage will also be presented to indicate the progress to date.

Summary of the mineralogy of the Colorado Plateau uranium ores

USGS Publications Warehouse

Weeks, Alice D.; Coleman, Robert Griffin; Thompson, Mary E.

1956-01-01

In the Colorado Plateau uranium has been produced chiefly from very shallow mines in carnotite ores (oxidized vanadiferous uranium ores) until recent deeper mining penetrated black unoxidized ores in water-saturated rocks and extensive exploration has discovered many deposits of low to nonvanadiferous ores. The uranium ores include a wide range from highly vanadiferous and from as much as one percent to a trace of copper, and contain a small amount of iron and traces of lead, zinc, molybdenum, cobalt, nickel, silver, manganese, and other metals. Recent investigation indicates that the carnotite ores have been derived by progressive oxidation of primary (unoxidized) black ores that contain low-valent uranium and vanadium oxides and silicates. The uranium minerals, uraninite and coffinite, are associated with coalified wood or other carbonaceous material. The vanadium minerals, chiefly montroseite, roscoelite, and other vanadium silicates, occur in the interstices of the sandstone and in siltstone and clay pellets as well as associated with fossil wood. Calcite, dolomite, barite and minor amounts of sulfides, arsenides, and selenides occur in the unoxidized ore. Partially oxidized vanadiferous ore is blue black, purplish brown, or greenish black in contrast to the black or dark gray unoxidized ore. Vanadium combines with uranium to form rauvite. The excess vanadium is present in corvusite, fernandinite, melanovanadite and many other quadrivalent and quinquevalent vanadium minerals as well as in vanadium silicates. Pyrite and part or all of the calcite are replaced by iron oxides and gypsum. In oxidized vanadiferous uranium ores the uranium is fixed in the relatively insoluble minerals carnotite and tyuyamunite, and the excess vanadium commonly combines with one or more of the following: calcium, sodium, potassium, magnesium, aluminum, iron, copper, manganese, or barium, or rarely it forms the hydrated pentoxide. The relatively stable vanadium silicates are little affected by oxidation. The unoxidized nonvanadiferous ores contain uraninite and coffinite in close association with coalified wood and iron and copper sulfides, and traces of many other sulfides, arsenides and selenides. The oxidized nonvanadiferous ores differ from the vanadiferous ores because, in the absence of vanadium to complex the uranium, a great variety of secondary yellow and greenish-yellow uranyl minerals are formed. The uranyl sulfates and carbonates are more common than the oxides, phosphates, arsenates, and silicates. Because the sulfates and carbonates are much less stable that carnotite, the oxidized nonvanadiferous ores occure only as halos around cores of unoxidized ore and do not form large oxidized deposits close to the surface of the ground as carnotite ores. Oxidation has taken place since the lowering of the water table in the present erosion cycle. Because of local structures and the highly lenticular character of the fluviatile host rocks perched water tables and water-saturated lenses of sandstone are common high above the regional water table. Unoxidized ore has been preserved in these water-saturated rocks and the boundary between oxidized and unoxidized ore is very irregular.

Torngat ultramafic lamprophyres and their relation to the North Atlantic Alkaline Province

NASA Astrophysics Data System (ADS)

Tappe, Sebastian; Jenner, George A.; Foley, Stephen F.; Heaman, Larry; Besserer, Dean; Kjarsgaard, Bruce A.; Ryan, Bruce

2004-09-01

Geological mapping and diamond exploration in northern Quebec and Labrador has revealed an undeformed ultramafic dyke swarm in the northern Torngat Mountains. The dyke rocks are dominated by an olivine-phlogopite mineralogy and contain varying amounts of primary carbonate. Their mineralogy, mineral compositional trends and the presence of typomorphic minerals (e.g. kimzeyitic garnet), indicate that these dykes comprise an ultramafic lamprophyre suite grading into carbonatite. Recognized rock varieties are aillikite, mela-aillikite and subordinate carbonatite. Carbonatite and aillikite have in common high carbonate content and a lack of clinopyroxene. In contrast, mela-aillikites are richer in mafic silicate minerals, in particular clinopyroxene and amphibole, and contain only small amounts of primary carbonate. The modal mineralogy and textures of the dyke varieties are gradational, indicating that they represent end-members in a compositional continuum. The Torngat ultramafic lamprophyres are characterized by high but variable MgO (10-25 wt.%), CaO (5-20 wt.%), TiO2 (3-10 wt.%) and K2O (1-4 wt.%), but low SiO2 (22-37 wt.%) and Al2O3 (2-6 wt.%). Higher SiO2, Al2O3, Na2O and lower CO2 content distinguish the mela-aillikites from the aillikites. Whereas the bulk rock major and trace element concentrations of the aillikites and mela-aillikites overlap, there is no fractional crystallization relation between them. The major and trace element characteristics imply related parental magmas, with minor olivine and Cr-spinel fractionation accounting for intra-group variation. The Torngat ultramafic lamprophyres have a Neoproterozoic age and are spatially and compositionally closely related with the Neoproterozoic ultramafic lamprophyres from central West Greenland. Ultramafic potassic-to-carbonatitic magmatism occurred in both eastern Laurentia and western Baltica during the Late Neoproterozoic. It can be inferred from the emplacement ages of the alkaline complexes and timing of Late Proterozoic processes in the North Atlantic region that this volatile-rich, deep-seated igneous activity was a distal effect of the breakup of Rodinia. This occurred during and/or after the rift-to-drift transition that led to the opening of the Iapetus Ocean.

Greenhouse effects due to man-made perturbations of trace gases

NASA Technical Reports Server (NTRS)

Wang, W. C.; Yung, Y. L.; Lacis, A. A.; Mo, T.; Hansen, J. E.

1976-01-01

Nitrous oxide, methane, ammonia, and a number of other trace constituents of the earth's atmosphere have infrared absorption bands in the spectral range from 7 to 14 microns. Despite their small amounts, these gases can have a significant effect on the thermal structure of the atmosphere by transmitting most of the thermal radiation from the earth's surface to the lower atmosphere. In the present paper, this greenhouse effect is computed for a number of trace gases. The nature and climatic implications of possible changes in the concentrations of N2O, CH4, NH3, and HNO3 are discussed.

Determination of 20 trace elements and arsenic species for a realgar-containing traditional Chinese medicine Niuhuang Jiedu tablets by direct inductively coupled plasma-mass spectrometry and high performance liquid chromatography-inductively coupled plasma-mass spectrometry.

PubMed

Jin, Pengfei; Liang, Xiaoli; Xia, Lufeng; Jahouh, Farid; Wang, Rong; Kuang, Yongmei; Hu, Xin

2016-01-01

Niuhuang Jiedu tablet (NHJDT) is a realgar-containing traditional Chinese medicine. A direct inductively coupled plasma-mass spectrometry (ICP-MS) method for the simultaneous determination of 20 trace elements (Mg, K, Ca, Na, Fe, As, Zn, Sr, Ba, Cu, Mn, Ni, Pb, V, Cr, Se, Co, Mo, Cd, Hg) in NHJDT, as well as in water, gastric fluid and intestinal fluid was established. Meanwhile, a high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS) method was developed for the determination of arsenite (As(III)), arsenate (As(V)), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and for the identification of arsenobetaine (AsB) and arsenocholine (AsC) in these extracts. Both methods were fully validated in the respect of linearity, sensitivity, precision, stability and accuracy. The reliability of the ICP-MS method was further evaluated using a certified standard reference material prepared from dried tomato leaves (NIST, SRM 1572a). The analysis showed that some manufacturers formulated lower amount of realgar than required in the Chinese Pharmacopoeia (ChP) in their preparations. In addition, almost same extraction profiles for total As and inorganic As were found in water and in gastrointestinal fluids, while higher extraction rates for other 19 elements were observed in gastrointestinal fluids. Our findings show that the toxicities of Hg, Cu, Cd and Pb in NHJDP are low, while the real As toxicity in NHJDT should be deeply investigated. Copyright © 2015 Elsevier GmbH. All rights reserved.

Bioaccumulation of macro- and trace elements by European frogbit (Hydrocharis morsus-ranae L.) in relation to environmental pollution.

PubMed

Polechońska, Ludmiła; Samecka-Cymerman, Aleksandra

2016-02-01

The aim of present study was to investigate the level of trace metals and macroelements in Hydrocharis morsus-ranae collected from regions differing in the degree and type of pollution. Concentrations of 17 macro- and microelements were determined in roots and shoots of European frogbit as well as in water and bottom sediments from 30 study sites. Plants differed in concentrations of elements and bioaccumulation capacity depending on the characteristics of dominant anthropogenic activities in the vicinity of the sampling site. Shoots of H. morsus-ranae growing in the vicinity of organic chemistry plants and automotive industry contained particularly high levels of Cd, Co, and S. Plants from area close to heat and power plant, former ferrochrome industry and new highway, were distinguished by the highest concentrations of Cr, Cu, and Pb. European frogbit from both these regions contained more Fe, Hg, Mn, Ni, and Zn than plants from agricultural and recreational areas. The concentrations of alkali metals and Co, Fe, and N in H. morsus-ranae were elevated in relation to the natural content in macrophytes irrespectively to their content in the environment. Based on the values of Bioaccumulation and Translocation Factors, European frogbit is an accumulator for Co, Cr, Cu, Fe, K, Mn, Ni, Pb, and Zn and a good candidate for phytoremediation of water polluted with Co, Cu, Hg, K, Mn, and Ni. The amount of Co and Mn removed from water and accumulated in the plant biomass during the vegetation season was considerably high.

The Environmental Measurements Laboratory's Stratospheric Radionuclide (RANDAB) and Trace Gas (TRACDAB) Databases

DOE Data Explorer

Leifer, Robert [Environmental Measurements Lab. (EML), New York, NY (United States); Chan, Nita [Environmental Measurements Lab. (EML), New York, NY (United States)

1997-01-01

RANDAB represents the worlds largest collection of stratospheric and upper tropospheric radionuclide data. The database contains results of measurements made from 1957 to 1983 during the ASHCAN, STARDUST, AIRSTREAM, and High Altitude Sampling Program (HASP) projects. More than 20,000 filters were collected during this period and analyzed for approximately 40 different radionuclides. All of the available data characterizing each filter are included in RANDAB. RANDAB offers gas samples characterizing the tritium, radon and 14CO2 concentration in stratospheric air. Only a limited amount of data is available for radon because of analytical and sampling problems. The tritium data were provided graciously by Dr. Allen Mason of Los Alamos Laboratory and Dr. H. G. Oslund of the Tritium Laboratory, University of Miami. The second database, TRACDAB, contains more than 1000 stratospheric trace gas measurements for the period 1974 to 1983. These samples were collected during Project AIRSTREAM. During the years 1974 to 1976, the samples were analyzed at EML. Subsequently, Washington State University (1976-1979) and the Oregon Graduate Institute for Science & Technology (formerly the Oregon Graduate Center 1980-1983) were under contract to EML to analyze AIRSTREAM gas samples. During the period 1974-1983, 980 gas samples were analyzed for one or more of the following gases CCl3F, CCl2F2, CCl4, CH3CCl3, SF6, N20, CO2, CH4, and carbonyl sulfide (COS). To learn more about the naming of halocarbons (CFCs, HFCs, HCFCs, and halons), go to http://cdiac.ess-dive.lbl.gov/pns/cfcinfo.html.

The SNPforID Assay as a Supplementary Method in Kinship and Trace Analysis

PubMed Central

Schwark, Thorsten; Meyer, Patrick; Harder, Melanie; Modrow, Jan-Hendrick; von Wurmb-Schwark, Nicole

2012-01-01

Objective Short tandem repeat (STR) analysis using commercial multiplex PCR kits is the method of choice for kinship testing and trace analysis. However, under certain circumstances (deficiency testing, mutations, minute DNA amounts), STRs alone may not suffice. Methods We present a 50-plex single nucleotide polymorphism (SNP) assay based on the SNPs chosen by the SNPforID consortium as an additional method for paternity and for trace analysis. The new assay was applied to selected routine paternity and trace cases from our laboratory. Results and Conclusions Our investigation shows that the new SNP multiplex assay is a valuable method to supplement STR analysis, and is a powerful means to solve complicated genetic analyses. PMID:22851934

Atmospheric Deposition of Trace Elements in Ombrotrophic Peat as a Result of Anthropic Activities

NASA Astrophysics Data System (ADS)

Fabio Lourençato, Lucio; Cabral Teixeira, Daniel; Vieira Silva-Filho, Emmanoel

2014-05-01

Ombrotrophic peat can be defined as a soil rich in organic matter, formed from the partial decomposition of vegetable organic material in a humid and anoxic environment, where the accumulation of material is necessarily faster than the decomposition. From the physical-chemical point of view, it is a porous and highly polar material with high adsorption capacity and cation exchange. The high ability of trace elements to undergo complexation by humic substances happens due to the presence of large amounts of oxygenated functional groups in these substances. Since the beginning of industrialization human activities have scattered a large amount of trace elements in the environment. Soil contamination by atmospheric deposition can be expressed as a sum of site contamination by past/present human activities and atmospheric long-range transport of trace elements. Ombrotrophic peat records can provide valuable information about the entries of trace metals into the atmosphere and that are subsequently deposited on the soil. These trace elements are toxic, non-biodegradable and accumulate in the food chain, even in relatively low quantities. Thus studies on the increase of trace elements in the environment due to human activities are necessary, particularly in the southern hemisphere, where these data are scarce. The aims of this study is to evaluate the concentrations of mercury in ombrotrophic peat altomontanas coming from atmospheric deposition. The study is conducted in the Itatiaia National Park, Brazilian conservation unit, situated between the southeastern state of Rio de Janeiro, São Paulo and Minas Gerais. An ombrotrophic peat core is being sampled in altitude (1980m), to measure the trace elements concentrations of this material. As it is conservation area, the trace elements found in the samples is mainly from atmospheric deposition, since in Brazil don't exist significant lithology of trace elements. The samples are characterized by organic matter content which is determined by calcination and pH. For the determination of mercury, an aliquot of 10 mL of sample with 5 mL of the reducing agent 2 % SnCl2, purged with air by atomic absorption spectrophotometry by cold vapor, EAAVF is being used. The determination of other trace elements (Zn, Cd and Pb) is analyzed by flame atomic absorption spectroscopy (FAAS).

Effects of fertilizer placement on trace gas emissions from container-grown plant production

USDA-ARS?s Scientific Manuscript database

Increased trace gas emissions of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) are widely believed to be a primary cause of global warming. Agriculture is a large contributor to these emissions; however, its role in climate change is unique in that it can act as a source of trace gas ...

Effects of fertilizer placement on trace gas emissions from nursery container production

USDA-ARS?s Scientific Manuscript database

Increased trace gas emissions of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) are widely believed to be a primary cause of global warming. Agriculture is a large contributor to these emissions; however, its role in climate change is unique in that it can act as a source of trace gas ...

Photoacoustic Effect of Ethene: Sound Generation due to Plant Hormone Gases.

NASA Astrophysics Data System (ADS)

Park, Han Jung; Ide, David; University of Tennessee at Chattanooga Team

2017-01-01

Ethene, which is produced in plants as they mature, was used to study its photoacoustic properties using photoacoustic spectroscopy. Detection of trace amounts, with N2 gas, of the ethylene gas were also applied. The gas was tested in various conditions: temperature, concentration of the gas, gas cell length, and power of the laser, were varied to determine their effect on the photoacoustic signal, the ideal conditions to detect trace gas amounts, and concentration of ethylene produced by an avocado and banana. A detection limit of 10 ppm was determined for pure C2H4. A detection of 5% and 13% (by volume) concentration of ethylene were produced for a ripening avocado and banana, respectively, in closed space.

CO 2 leakage impacts on shallow groundwater. Field-scale reactive-transport simulations informed by observations at a natural analog site

DOE PAGES

Keating, Elizabeth H.; Hakala, J. Alexandra; Viswanathan, Hari; ...

2013-03-01

It is challenging to predict the degree to which shallow groundwater might be affected by leaks from a CO 2 sequestration reservoir, particularly over long time scales and large spatial scales. In this study observations at a CO 2 enriched shallow aquifer natural analog were used to develop a predictive model which is then used to simulate leakage scenarios. This natural analog provides the opportunity to make direct field observations of groundwater chemistry in the presence of elevated CO 2, to collect aquifer samples and expose them to CO 2 under controlled conditions in the laboratory, and to test themore » ability of multiphase reactive transport models to reproduce measured geochemical trends at the field-scale. The field observations suggest that brackish water entrained with the upwelling CO 2 are a more significant source of trace metals than in situ mobilization of metals due to exposure to CO 2. The study focuses on a single trace metal of concern at this site: U. Experimental results indicate that cation exchange/adsorption and dissolution/precipitation of calcite containing trace amounts of U are important reactions controlling U in groundwater at this site, and that the amount of U associated with calcite is fairly well constrained. Simulations incorporating these results into a 3-D multi-phase reactive transport model are able to reproduce the measured ranges and trends between pH, pCO 2, Ca, total C, U and Cl -at the field site. Although the true fluxes at the natural analog site are unknown, the cumulative CO 2 flux inferred from these simulations are approximately equivalent to 37.8E-3 MT, approximately corresponding to a .001% leak rate for injection at a large (750 MW) power plant. The leakage scenario simulations suggest that if the leak only persists for a short time the volume of aquifer contaminated by CO 2-induced mobilization of U will be relatively small, yet persistent over 100 a.« less

Temperature and Gravity Dependence of Trace Element Abundances in Hot DA White Dwarfs (94-EUVE-094)

NASA Technical Reports Server (NTRS)

Finley, David S.

1998-01-01

EUV spectroscopy has shown that DA white dwarfs hotter than about 45,000 K may contain trace heavy elements, while those hotter than about 50,000 K almost always have significant abundances of trace heavy elements. One of our continuing challenges is to identify and determine the abundances of these trace constituents, and then to relate the observed abundance patterns to the present conditions and previous evolutionary histories of the hot DA white dwarfs.

Geochemistry of ultramafic xenoliths from Kapfenstein, Austria: evidence for a variety of upper mantle processes

NASA Astrophysics Data System (ADS)

Kurat, G.; Palme, H.; Spettel, B.; Baddenhausen, Hildegard; Hofmeister, H.; Palme, Christl; Wänke, H.

1980-01-01

Major, minor, and trace element contents have been determined in seven ultramafic xenoliths, the host basanite, and some mineral separates from xenoliths from Kapfenstein, Austria. Most of the xenoliths represent residues after extraction of different amounts of basaltic liquid. Within the sequence Iherzolite to harzburgite contents of Al, Ca, Ti, Na, Sc, V, Cr and the HREE decrease systematically with increasing Mg/Fe and decreasing Yb/Sc. Although all samples are depleted in highly incompatible elements, the less depleted end of our suite very closely approaches the chondritic Yb/Sc ratio and consequently the primitive upper mantle composition. Chromium behaved as a non-refractory element. Consequently it should have higher abundances in basalts than observed, suggesting that most basalts experienced Cr fractionation by chromite separation during ascent. Several processes have been active in addition to partial melting within the upper mantle beneath Kapfenstein: (1) a hornblendite has been identified as wet alkali-basaltic mobilisate; (2) an amphibole Iherzolite is the product of alkali-basalt metasomatism of a common depleted Iherzolite; (3) two amphibole Iherzolites contain evidence for rather pure water metasomatism of normal depleted Iherzolites; (4) a garnet-spinel websterite was a tholeiitic liquid trapped within the upper mantle and which suffered a subsequent partial melting event (partial remobilization of a mobilisate). (5) Abundances of highly incompatible elements are generally very irregular, indicating contamination of upper mantle rocks by percolating liquids (in the mantle). Weathering is an important source of contamination: e.g. U mobilization by percolating groundwater. Contamination of the xenoliths by the host basanite liquid can only amount to approximately 5.5 × 10 -4 parts. Distributions of minor and trace elements between different minerals apparently reflect equilibrium and vary with equilibration temperature.

Sintering polycrystalline olivine and polycrystalline clinopyroxene containing trace amount of graphite from natural crystals

NASA Astrophysics Data System (ADS)

Tsubokawa, Yumiko; Ishikawa, Masahiro

2017-09-01

Graphite-bearing polycrystalline olivine and polycrystalline clinopyroxene with submicron to micron grain size were successfully sintered from a single crystal of naturally occurring olivine (Fo88-92Fa12-8: Mg1.76-1.84Fe0.16-0.24SiO4) and a single crystal of naturally occurring clinopyroxene (Di99Hed1: Ca0.92Na0.07Mn0.01Mg0.93Fe0.01Al0.06Si2O6). The milled powders of both these crystals were sintered under argon gas flow at temperatures ranging from 1130 to 1350 °C for 2 h. As the sintering temperature increased, the average grain size of olivine increased from 0.2 to 1.4 µm and that of clinopyroxene increased from 0.1 to 2.4 µm. The porosity of sintered samples remained at an almost-constant volume of 2-5% for olivine and 3-4% for clinopyroxene. The samples sintered from powders milled with ethanol exhibited trace amount of graphite, identified via Raman spectroscopy analysis. As the sintering temperature increased, the intensity of the graphite Raman peak decreased, compared with both olivine and clinopyroxene peaks. The carbon content of the sintered samples was estimated to be a few hundred ppm. The in-plane size ( L a ) of graphite in the sintered olivine was estimated to be <15 nm. Our experiments demonstrate new possibilities for preparing graphite-bearing silicate-mantle mineral rocks, and this method might be useful in understanding the influence of the physical properties of graphite on grain-size-sensitive rheology or the seismic velocity of the Earth's mantle.[Figure not available: see fulltext.

From waste water treatment to land management: Conversion of aquatic biomass to biochar for soil amelioration and the fortification of crops with essential trace elements.

PubMed

Roberts, David A; Paul, Nicholas A; Cole, Andrew J; de Nys, Rocky

2015-07-01

Macroalgae can be grown in industrial waste water to sequester metals and the resulting biomass used for biotechnological applications. We have previously cultivated the freshwater macroalga Oedogonium at a coal-fired power station to treat a metal-contaminated effluent from that facility. We then produced biochar from this biomass and determined the suitability of both the biomass and the biochar for soil amelioration. The dried biomass of Oedogonium cultivated in the waste water contained several elements for which there are terrestrial biosolids criteria (As, Cd, Cr, Cu, Pb, Ni, Se and Zn) and leached significant amounts of these elements into solution. Here, we demonstrate that these biomass leachates impair the germination and growth of radishes as a model crop. However, the biochar produced from this same biomass leaches negligible amounts of metal into solution and the leachates support high germination and growth of radishes. Biochar produced at 750 °C leaches the least metal and has the highest recalcitrant C content. When this biochar is added to a low-quality soil it improves the retention of nutrients (N, P, Ca, Mg, K and Mo) from fertilizer in the soil and the growth of radishes by 35-40%. Radishes grown in the soils amended with the biochar have equal or lower metal contents than radishes grown in soil without biochar, but much higher concentrations of essential trace elements (Mo) and macro nutrients (P, K, Ca and Mg). The cultivation of macroalgae is an effective waste water bioremediation technology that also produces biomass that can be used as a feedstock for conversion to biochar for soil amelioration. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mercury exposure, nutritional deficiencies and metabolic disruptions may affect learning in children

PubMed Central

Dufault, Renee; Schnoll, Roseanne; Lukiw, Walter J; LeBlanc, Blaise; Cornett, Charles; Patrick, Lyn; Wallinga, David; Gilbert, Steven G; Crider, Raquel

2009-01-01

Among dietary factors, learning and behavior are influenced not only by nutrients, but also by exposure to toxic food contaminants such as mercury that can disrupt metabolic processes and alter neuronal plasticity. Neurons lacking in plasticity are a factor in neurodevelopmental disorders such as autism and mental retardation. Essential nutrients help maintain normal neuronal plasticity. Nutritional deficiencies, including deficiencies in the long chain polyunsaturated fatty acids eicosapentaenoic acid and docosahexaenoic acid, the amino acid methionine, and the trace minerals zinc and selenium, have been shown to influence neuronal function and produce defects in neuronal plasticity, as well as impact behavior in children with attention deficit hyperactivity disorder. Nutritional deficiencies and mercury exposure have been shown to alter neuronal function and increase oxidative stress among children with autism. These dietary factors may be directly related to the development of behavior disorders and learning disabilities. Mercury, either individually or in concert with other factors, may be harmful if ingested in above average amounts or by sensitive individuals. High fructose corn syrup has been shown to contain trace amounts of mercury as a result of some manufacturing processes, and its consumption can also lead to zinc loss. Consumption of certain artificial food color additives has also been shown to lead to zinc deficiency. Dietary zinc is essential for maintaining the metabolic processes required for mercury elimination. Since high fructose corn syrup and artificial food color additives are common ingredients in many foodstuffs, their consumption should be considered in those individuals with nutritional deficits such as zinc deficiency or who are allergic or sensitive to the effects of mercury or unable to effectively metabolize and eliminate it from the body. PMID:19860886

Liquid Chromatographic Analysis of Hydraulic Fluids.

DTIC Science & Technology

1979-11-01

chemical mixtures of a petroleum- or nonpetroleum-base stock component formulated with various additives which may be present in trace amounts or...absorb UV radiation near the monitoring wavelength may swamp the detector signal and therefore should be avoided in 1JV detection. The recorder trace of...Also, organic phosphites , thiophosphates, and sulfides are used to inhibit oxidative catalysis by metal ions. The oxidation inhibitor in 6083D-0 is BPC

Passive inhalation of cocaine.

PubMed

Cone, E J; Yousefnejad, D; Hillsgrove, M J; Holicky, B; Darwin, W D

1995-10-01

Six healthy male volunteers were exposed to the vapor of 100 and 200 mg freebase cocaine heated to a temperature of 200 degrees C in an unventilated room (12,600-L volume) for a period of 1 h. No pharmacological effects were detected as a result of the exposure. Blood specimens collected immediately following exposure were negative for cocaine and metabolites. Urine specimens analyzed by gas chromatography-mass spectrometry contained peak concentrations of benzoylecgonine that ranged from 22 to 123 ng/mL. The peak excretion time for benzoylecgonine following passive exposure was approximately 5 h. The amount of cocaine inhaled by the subjects during passive exposure was estimated from room air measurements of cocaine to be approximately 0.25 mg. The total amount of cocaine (cocaine plus metabolites) excreted in urine by the six subjects ranged from 0.04 to 0.21 mg. For comparison, the six subjects also received an intravenous injection of 1 mg cocaine hydrochloride. Four of six subjects screened positive (300-ng/mL cutoff concentration) following the injection, indicating that the minimum amount of cocaine in these subjects necessary to produce positive results was approximately 1 mg. A second passive inhalation study was undertaken in which specimens were collected from research staff who assisted in a series of experimental studies with "crack" (freebase cocaine) smokers. The research staff remained in close vicinity while the crack smokers smoked three doses of freebase cocaine (12.5, 25, and 50 mg) over a period of 4 h. As a result, staff members were passively exposed to sidestream smoke from crack pipes and to breath exhalation from the crack smokers. Urine specimens from the staff members contained a maximum of 6 ng/mL benzoylecgonine. Only traces (less than 1 ng/mL) of cocaine were detected in any specimen. Overall, these studies demonstrated that individuals exposed to cocaine smoke under naturalistic or artificial conditions absorbed small amounts of cocaine that were insufficient to produce positive urine specimens at standard Department of Health and Human Services cutoffs. However, passive exposure conditions that would result in absorption of cocaine in amounts exceeding 1 mg could result in the production of cocaine-positive urine specimens.

Trace desulfurization. [DOE patent application

DOEpatents

Chen, H.L.; Stevens, C.G.

A method for reducing a trace concentration of sulfur-containing compounds in a gas stream from about one part in 10/sup 4/ to about one part in 10/sup 7/. The method includes the steps of irradiating the gas stream with an energy source which has a central emission frequency chosen to substantially match a wavelength of energy absorption of the sulfur-containing compounds and of subsequently contacting the gas stream with a reactive surface which includes a reactant selected from elemental metals and metal oxides so that metallic sulfur-containing compounds are formed. The reduction in concentration allows the gas stream to be processed in certain reactions having catalysts which would otherwise be poisoned by the sulfur-containing compounds.

Consumer-producer relationships for trace metals in Chorthippus brunneus (Thunberg. )

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

Johnson, M.S.

1986-08-01

The behavior of trace metals in terrestrial food chains is a subject of ecological interest, particularly in polluted environments where the potential exists for bioconcentration of metals known to be essential in trace amounts for normal plant and animal metabolism, as well as those with no known metabolic function but recognized toxicological properties. Laboratory studies of food chain relationships afford a means by which direct comparisons can be made between trace metals as a basis for interpretation of data collected from wild plant and animal populations. This study compares the behavior of three trace elements, copper, zinc and cadmium, inmore » terms of their assimilation under experimental conditions by the herbivorous common field grasshopper, Chorthippus brunneus (Thunberg.). This voracious orthopteran is widely distributed in Britain and is particularly prominent in the restricted invertebrate community of some metal smelter-affected grasslands where it forms important seasonal prey for insectivorous small mammals.« less

Allergenicity of milk of different animal species in relation to human milk.

PubMed

Pastuszka, Robert; Barłowska, Joanna; Litwińczuk, Zygmunt

2016-12-31

Protein content in cow milk (with over 20 proteins, and peptides may also occur as a result of enzymatic hydrolysis) ranges from 2.5% to 4.2% and is about 1.5-2 times higher than in human milk. Its most important allergens are considered to be β-lactoglobulin (absent in human milk) and αs1-casein. The most similar in composition to human milk is horse and donkey milk. It contains considerably more whey proteins (35-50%) than cow milk (about 20%), and the concentration of the most allergenic casein fraction αs1 is 1.5-2.5 g/l. In comparison, the content of αs1-casein in cow milk is about 10 g/l. β-lactoglobulin present in donkey milk is a monomer, while in milk of ruminants it is a dimer. Like human milk, it contains a substantial amount of lactose (about 7%), which determines its flavour and facilitates calcium absorption. The high lysozyme content (about 1 g/l) gives it antibacterial properties (compared to trace amounts in ruminants). Camel milk is also more digestible and induces fewer allergic reactions, because it lacks β-lactoglobulin, and its β-casein has a different structure. It also contains (compared to cow milk) more antibacterial substances such as lysozyme, lactoferrin and immunoglobulins, and furthermore the number of immunoglobulins is compatible with human ones. Goat milk components have a higher degree of assimilability as compared to cow milk. Its main protein is β-casein, with total protein content depending on the αs1-casein genetic variant. Goats with the '0' variant do not synthesize this allergenic protein. Clinical and immunochemical studies indicate, however, that it cannot be a substitute for cow milk without the risk of an anaphylactic reaction.

Impact of Magnetic Stirring on Stainless Steel Integrity: Effect on Biopharmaceutical Processing.

PubMed

Thompson, Christopher; Wilson, Kelly; Kim, Yoen Joo; Xie, Min; Wang, William K; Wendeler, Michaela

2017-11-01

Stainless steel containers are widely used in the pharmaceutical and biopharmaceutical industry for the storage of buffers, process intermediates, and purified drug substance. They are generally held to be corrosion resistant, biocompatible, and nonreactive, although it is well established that trace amounts of metal ions can leach from stainless steel equipment into biopharmaceutical products. We report here that the use of stainless steel containers in conjunction with magnetic stirring bars leads to significantly aggravated metal contamination, consisting of both metal particles and significantly elevated metal ions in solution, the degree of which is several orders of magnitude higher than described for static conditions. Metal particles are analyzed by scanning electron microscopy with electron-dispersive X-ray spectroscopy, and metal content in solution is quantitated at different time points by inductively coupled plasma-mass spectrometry. The concentration of iron, chromium, nickel, and manganese increases with increasing stirring time and speed. We describe the impact of buffer components on the extent of metal particles and ions in solution and illustrate the effect on model proteins. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Nutritive Evaluation of the Bambara Groundnut Ci12 Landrace [Vigna subterranea (L.) Verdc. (Fabaceae)] Produced in Côte d’Ivoire

PubMed Central

N’Dri Yao, Denis; Kouassi, Kouakou Nestor; Erba, Daniela; Scazzina, Francesca; Pellegrini, Nicoletta; Casiraghi, Maria Cristina

2015-01-01

The nutritional evaluation of the Bambara groundnut Ci12 landrace (Vigna subterranea (L.) Verdc.) seeds produced in Côte d’Ivoire shows a 19% content of protein, containing all the essential amino acids with tryptophan as the limiting amino acid, a total dietary fiber level of 10%, with a low soluble fraction content, and a fat content of 1.4%, with a high proportion of total unsaturated fatty acids (61%) of which 36% were n-6 fatty acids. This legume contains phosphorus, as the major mineral, followed by magnesium and calcium, and trace elements (iron, copper and zinc). It is characterized by the same amount of α-tocopherol and antioxidant capacity as common legumes. The high concentration of essential amino acids, n-6 fatty acids and minerals, mainly Fe, in the Ci12 landrace of Bambara groundnut indicates that this local legume has the potentiality to improve the nutritional status in Côte d’Ivoire and it could be regarded as a nutrient dense food. PMID:26370971

Nutritive Evaluation of the Bambara Groundnut Ci12 Landrace [Vigna subterranea (L.) Verdc. (Fabaceae)] Produced in Côte d'Ivoire.

PubMed

Yao, Denis N'Dri; Kouassi, Kouakou Nestor; Erba, Daniela; Scazzina, Francesca; Pellegrini, Nicoletta; Casiraghi, Maria Cristina

2015-09-07

The nutritional evaluation of the Bambara groundnut Ci12 landrace (Vigna subterranea (L.) Verdc.) seeds produced in Côte d'Ivoire shows a 19% content of protein, containing all the essential amino acids with tryptophan as the limiting amino acid, a total dietary fiber level of 10%, with a low soluble fraction content, and a fat content of 1.4%, with a high proportion of total unsaturated fatty acids (61%) of which 36% were n-6 fatty acids. This legume contains phosphorus, as the major mineral, followed by magnesium and calcium, and trace elements (iron, copper and zinc). It is characterized by the same amount of α-tocopherol and antioxidant capacity as common legumes. The high concentration of essential amino acids, n-6 fatty acids and minerals, mainly Fe, in the Ci12 landrace of Bambara groundnut indicates that this local legume has the potentiality to improve the nutritional status in Côte d'Ivoire and it could be regarded as a nutrient dense food.

Low VOC drying of lumber and wood panel products. Progress report Number 9 [January 1999

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

Yan, H.; Banerjee, S.; Conners, T.

1999-01-01

Results from a multi-year study show that a significant part of the extensive variability observed in oriented strand board (OSB) flake dryer emissions can be traced to physiological effects, and the rest can be attributed to handling and other factors. Low-headspace treatment of lumber was scaled up to the 50 kg level. The amount of turpentine collected was of the same magnitude as that released upon drying lumber. For the process to be economical, the wood must first be brought to about 95 C with steam, and then processed with RF. Attempts to remove VOCs from OSB through low-headspace bymore » placing a curtain over the wood failed because of leaks. A more rigid container will be required. RF-treatment does not alter the gas permeability of lumber.« less

Low VOC drying of lumber and wood panel products. Progress report Number 9

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

Yan, H.; Banerjee, S.; Conners, T.

1999-01-01

Results from a multi-year study show that a significant part of the extensive variability observed in oriented strand board (OSB) flake dryer emissions can be traced to physiological effects, and the rest can be attributed to handling and other factors. Low-headspace treatment of lumber was scaled up to the 50 kg level. The amount of turpentine collected was of the same magnitude as that released upon drying lumber. For the process to be economical, the wood must first be brought to about 95 C with steam, and then processed with RF. Attempts to remove VOCs from OSB through low-headspace bymore » placing a curtain over the wood failed because of leaks. A more rigid container will be required. RF-treatment does not alter the gas permeability of lumber.« less

Dissolution of alkaline earth sulfates in the presence of montmorillonite

USGS Publications Warehouse

Eberl, D.D.; Landa, E.R.

1985-01-01

In a study of the effect of montmorillonite on the dissolution of BaSO4 (barite), SrSO4 (celestite), and 226Ra from U mill tailings, it was found that: (1) More of these substances dissolve in an aqueous system that contains montmorillonite than dissolve in a similar system without clay, due to the ion exchange properties of the clay; (2) Na-montmorillonite is more effective in aiding dissolution than is Ca-montmorillonite; (3) the amount of Ra that moves from mill tailings to an exchanger increases as solution sulfate activity decreases. Leaching experiments suggest that 226Ra from H2SO4-circuit U mill tailings from Edgemont, South Dakota, is not present as pure Ra sulfate or as an impurity in anhydrite or gypsum; it is less soluble, and probably occurs as a trace constituent in barite.

Engineering of GlcNAc-1-Phosphotransferase for Production of Highly Phosphorylated Lysosomal Enzymes for Enzyme Replacement Therapy.

PubMed

Liu, Lin; Lee, Wang-Sik; Doray, Balraj; Kornfeld, Stuart

2017-06-16

Several lysosomal enzymes currently used for enzyme replacement therapy in patients with lysosomal storage diseases contain very low levels of mannose 6-phosphate, limiting their uptake via mannose 6-phosphate receptors on the surface of the deficient cells. These enzymes are produced at high levels by mammalian cells and depend on endogenous GlcNAc-1-phosphotransferase α/β precursor to phosphorylate the mannose residues on their glycan chains. We show that co-expression of an engineered truncated GlcNAc-1-phosphotransferase α/β precursor and the lysosomal enzyme of interest in the producing cells resulted in markedly increased phosphorylation and cellular uptake of the secreted lysosomal enzyme. This method also results in the production of highly phosphorylated acid β-glucocerebrosidase, a lysosomal enzyme that normally has just trace amounts of this modification.

Deep-level transient spectroscopy studies of Ni- and Zn-diffused vapor-phase-epitaxy n-GaAs

NASA Technical Reports Server (NTRS)

Partin, D. L.; Chen, J. W.; Milnes, A. G.; Vassamillet, L. F.

1979-01-01

The paper presents deep-level transient spectroscopy studies of Ni- and Zn-diffused vapor-phase epitaxy n-GaAs. Nickel diffused into VPE n-GaAs reduces the hole diffusion length L sub p from 4.3 to 1.1 microns. Deep-level transient spectroscopy was used to identify energy levels in Ni-diffused GaAs; the as-grown VPE GaAs contains traces of these levels and an electron trap. Ni diffusion reduces the concentration of this level by an amount that matches the increase in concentration of each of the two Ni-related levels. A technique for measuring minority-carrier capture cross sections was developed, which indicates that L sub p in Ni-diffused VPE n-GaAs is controlled by the E sub c - 0.39 eV defect level.

A simple method to extract DNA from hair shafts using enzymatic laundry powder.

PubMed

Guan, Zheng; Zhou, Yu; Liu, Jinchuan; Jiang, Xiaoling; Li, Sicong; Yang, Shuming; Chen, Ailiang

2013-01-01

A simple method to extract DNA from hair shafts was developed by using enzymatic laundry powder at the first step of the process. The whole extraction can be finished in less than 2 hours. The simple extraction reagent proposed here contains only two cheap components: ordinary enzymatic laundry powder and PCR buffer. After extraction, an ultra sensitive fluorescent nucleic acid stain, PicoGreen, was used for quantifying trace amount of double-stranded DNA in the solution extracted. For further validation of DNA extraction, four primers were employed to amplify DNA microsatellite loci. Both fluorescence spectroscopy and PCR results suggested that this method can extract DNA from hair shafts with good efficiency and repeatability. The study will greatly facilitate the use of hair shafts in future for DNA analyses on genome-wide scale.

Dry flue gas desulfurization by-product application effects on plant uptake and soil storage changes in a managed grassland.

PubMed

Burgess-Conforti, Jason R; Brye, Kristofor R; Miller, David M; Pollock, Erik D; Wood, Lisa S

2018-02-01

Environmental regulations mandate that sulfur dioxide (SO 2 ) be removed from the flue gases of coal-fired power plants, which results in the generation of flue gas desulfurization (FGD) by-products. These FGD by-products may be a viable soil amendment, but the large amounts of trace elements contained in FGD by-products are potentially concerning. The objective of this study was to evaluate the effects of land application of a high-Ca dry FGD (DFGD) by-product on trace elements in aboveground biomass and soil. A high-Ca DFGD by-product was applied once at a rate of 9 Mg ha -1 on May 18, 2015 to small plots with mixed-grass vegetation. Soil and biomass were sampled prior to application and several times thereafter. Aboveground dry matter and tissue As, Co, Cr, Hg, Se, U, and V concentrations increased (P < 0.05) following application, but did not differ (P > 0.05) from pre-application levels or the unamended control within 3 to 6 months of application. Soil pH in the amended treatment 6 months after application was greater (P < 0.05) than in the unamended control. Soil Ca, S, and Na contents also increased (P < 0.05), following by-product application compared to the unamended control. High-Ca DFGD by-products appear to be useful as a soil amendment, but cause at least a temporary increase in tissue concentrations of trace elements, which may be problematic for animal grazing situations.

A Method for Assessing the Retention of Trace Elements in Human Body Using Neural Network Technology

PubMed Central

Ragimov, Aligejdar; Faizullin, Rashat; Valiev, Vsevolod

2017-01-01

Models that describe the trace element status formation in the human organism are essential for a correction of micromineral (trace elements) deficiency. A direct trace element retention assessment in the body is difficult due to the many internal mechanisms. The trace element retention is determined by the amount and the ratio of incoming and excreted substance. So, the concentration of trace elements in drinking water characterizes the intake, whereas the element concentration in urine characterizes the excretion. This system can be interpreted as three interrelated elements that are in equilibrium. Since many relationships in the system are not known, the use of standard mathematical models is difficult. The artificial neural network use is suitable for constructing a model in the best way because it can take into account all dependencies in the system implicitly and process inaccurate and incomplete data. We created several neural network models to describe the retentions of trace elements in the human body. On the model basis, we can calculate the microelement levels in the body, knowing the trace element levels in drinking water and urine. These results can be used in health care to provide the population with safe drinking water. PMID:29065586

Micovascular integration into porous polyHEMA scaffold

NASA Astrophysics Data System (ADS)

Cho, Eugenia H.; Boico, Alina; Wisniewski, Natalie A.; Gant, Rebecca; Helton, Kristen L.; Brown, Nga L.; Register, Janna K.; Vo-Dinh, Tuan; Schroeder, Thies; Klitzman, Bruce

2014-03-01

Surface-enhanced Raman scattering (SERS) spectroscopy can be a useful tool in regard to disease diagnosis and prevention. Advantage of SERS over conventional Raman spectroscopy is its significantly increased signal (up to factor of 106-108) which allows detection of trace amounts of substances in the sample. So far, this technique is successfully used for analysis of food, pieces of art and various biochemical/biomedical samples. In this work, we survey the possibility of applying SERS spectroscopy for detection of trace components in urinary deposits. Early discovery together with the identification of the exact chemical composition of urinary sediments could be crucial for taking appropriate preventive measures that inhibit kidney stone formation or growth processes. In this initial study, SERS spectra (excitation wavelength - 1064 nm) of main components of urinary deposits (calcium oxalate, uric acid, cystine, etc.) were recorded by using silver (Ag) colloid. Spectra of 10-3-10-5 M solutions were obtained. While no/small Raman signal was detected without the Ag colloid, characteristic peaks of the substances could be clearly separated in the SERS spectra. This suggests that even small amounts of the components could be detected and taken into account while determining the type of kidney stone forming in the urinary system. We found for the first time that trace amounts of components constituting urinary deposits could be detected by SERS spectroscopy. In the future study, the analysis of centrifuged urine samples will be carried out.

The repair of low dose UV light-induced damage to human skin DNA in condition of trace amount Mg 2+

NASA Astrophysics Data System (ADS)

Gao, Fang; Guo, Zhouyi; Zheng, Changchun; Wang, Rui; Liu, Zhiming; Meng, Pei; Zhai, Juan

2008-12-01

Ultraviolet light-induced damage to human skin DNA was widely investigated. The primary mechanism of this damage contributed to form cyclobutane pyrimidine dimmers (CPDs). Although the distribution of UV light-induced CPDs within a defined sequence is similar, the damage in cellular environment which shields the nuclear DNA was higher than that in organism in apparent dose. So we use low UVB light as main study agent. Low dose UV-irradiated HDF-a cells (Human Dermal Fibroblasts-adult cells) which is weaker than epidermic cells were cultured with DMEM at different trace amount of Mg2+ (0mmol/L , 0.1mmol/L , 0.2mmol/L, 0.4mmol/L, 0.8mmol/L, 1.2mmol/L) free-serum DMEM and the repair of DNA strands injured were observed. Treat these cells with DNA strand breaks detection, photoproducts detection and the repair of photoproducts detection. Then quantitate the role of trace amount Mg2+ in repair of UV light-induced damage to human skin. The experiment results indicated that epidermic cells have capability of resistance to UV-radiation at a certain extent. And Mg2+ can regulate the UV-induced damage repair and relative vitality. It can offer a rationale and experiment data to relieve UV light-induced skin disease.

Analysis of memory use for improved design and compile-time allocation of local memory

NASA Technical Reports Server (NTRS)

Mcniven, Geoffrey D.; Davidson, Edward S.

1986-01-01

Trace analysis techniques are used to study memory referencing behavior for the purpose of designing local memories and determining how to allocate them for data and instructions. In an attempt to assess the inherent behavior of the source code, the trace analysis system described here reduced the effects of the compiler and host architecture on the trace by using a technical called flattening. The variables in the trace, their associated single-assignment values, and references are histogrammed on the basis of various parameters describing memory referencing behavior. Bounds are developed specifying the amount of memory space required to store all live values in a particular histogram class. The reduction achieved in main memory traffic by allocating local memory is specified for each class.

Fate of hazardous air pollutants in oxygen-fired coal combustion with different flue gas recycling.

PubMed

Zhuang, Ye; Pavlish, John H

2012-04-17

Experiments were performed to characterize transformation and speciation of hazardous air pollutants (HAPs), including SO(2)/SO(3), NO(x), HCl, particulate matter, mercury, and other trace elements in oxygen-firing bituminous coal with recirculation flue gas (RFG) from 1) an electrostatic precipitator outlet or 2) a wet scrubber outlet. The experimental results showed that oxycombustion with RFG generated a flue gas with less volume and containing HAPs at higher levels, while the actual emissions of HAPs per unit of energy produced were much less than that of air-blown combustion. NO(x) reduction was achieved in oxycombustion because of the elimination of nitrogen and the destruction of NO in the RFG. The elevated SO(2)/SO(3) in flue gas improved sulfur self-retention. SO(3) vapor could reach its dew point in the flue gas with high moisture, which limits the amount of SO(3) vapor in flue gas and possibly induces material corrosion. Most nonvolatile trace elements were less enriched in fly ash in oxycombustion than air-firing because of lower oxycombustion temperatures occurring in the present study. Meanwhile, Hg and Se were found to be enriched on submicrometer fly ash at higher levels in oxy-firing than in air-blown combustion.

Preconcentration of Zn2+ and Cu2+ ions from food and vegetable samples using modified activated carbon.

PubMed

Ghaedi, M; Tavallali, H; Montazerozohori, M; Zahedi, E; Amirineko, M; Khodadoust, S; Karimipour, G

2012-11-01

In this work, two N/S-containing chelating agents 2-(4-methoxybenzylideneamino)thiophenol (2-4-MBAT) and 2-(4-chlorobenzylideneamino) benzenethiol (2-4-CBABT) were synthesized as new sorbents and were used for preconcentration of Zn(2+) and Cu(2+) ions in food and vegetable samples. In the proposed procedure, the trace amount of Zn(2+) and Cu(2+) ions from 250 mL of sample solution at pH = 5.0 was preconcentrated by 1 g of activated carbon (AC) loaded with 15 mg of 2-4-MBAT and 2-4-CBABT separately. The breakthrough volumes (maximum sample volume that their metal ions quantitatively can be enriched) for solid-phase extraction (SPE) procedure based on the AC modified with 2-4-MBAT and 2-4-CBABT were 800 and 750 mL, respectively. The sorbed Zn(2+) and Cu(2+) ions were efficiently eluted by 8 mL of 4 mol L(-1) HNO(3) and preconcentration factor of 112.5 and 93.7 and experimental enhancement factor of 30 and 35 ions were obtained for Zn(2+) and Cu(2+), respectively. The application of this enrichment procedure allowed the extraction of trace metal ions with recoveries exceeding of 90%.

Particulate and trace gas emissions from prescribed burns in southeastern U.S. fuel types: Summary of a 5-year project

Treesearch

David R. Weise; Timothy J. Johnson; James Reardon

2015-01-01

Management of smoke from prescribed fires requires knowledge of fuel quantity and the amount and composition of the smoke produced by the fire to minimize adverse impacts on human health. A five-year study produced new emissions information for more than 100 trace gases and particulate matter in smoke for fuel types found in the southern United States of America using...

Elimination of cadmium trace contaminations from drinking water.

PubMed

Zhao, Xuan; Höll, Wolfgang H; Yun, Guichun

2002-02-01

Raw waters polluted with trace heavy metals present serious problems to the part of the Chinese water supply. One of the important contaminants is cadmium. Removal of trace amounts of heavy metals can be achieved by means of selective sorption processes. One of the possibilities is the application of weak base anion exchangers. LEWIS-base/acid interactions lead to an exclusive sorption of heavy metal cations and an equivalent amount of anions of strong acids. The respective elimination of cadmium from pure solutions and spiked natural water and the regeneration of the exhausted exchanger has been investigated. The results demonstrate a very efficient elimination. The standards for drinking water are met for a very large relative volume of treated water. In addition, even a considerable share of dissolved organic matter is adsorbed. Regeneration requires a first step with sulfuric acid to remove the metals and a second one with sodium hydroxide to neutralize the exchanger and to displace the DOC adsorbed. The heavy metals can be concentrated in a small volume which facilitates the discharge of the waste.

Is violence in part a lithium deficiency state?

PubMed

Goldstein, Mark R; Mascitelli, Luca

2016-04-01

Violence, particularly firearm violence, leading to suicide and homicide is a significant problem worldwide. A majority of suicidal and homicidal violence involves males; homicidal violence is prevalent among young men and suicide is the leading cause of violence worldwide. Lithium, in pharmacological doses, has been used successfully for decades in treating bipolar disorders, and has been shown to decrease violent crime in this situation. Interestingly, lithium, in trace amounts, as occurs in some drinking water, has been inversely related to aggression, and suicidal and homicidal violence. Lithium is naturally found in vegetables, grains and drinking water, and dietary intake varies from nearly zero to 3mg daily. Elemental lithium, in trace doses, has been shown to improve mood in weeks. Moreover, lithium, in trace amounts, has no toxicity. In order to ensure adequate dietary intakes of elemental lithium daily for the purpose of decreasing aggression and violence, we propose considering the fortification of cereal grain products with lithium and also the addition of lithium to vitamin preparations for adults. Importantly, randomized trials in various populations are needed to test this hypothesis. Copyright © 2016 Elsevier Ltd. All rights reserved.

Secrets of the Past.

ERIC Educational Resources Information Center

Naturescope, 1987

1987-01-01

Provides background information on how scientists have learned about the history of the Earth, including studying fossils, dating rocks, and tracing geological movements. Included are teaching activities about prehistoric animals, state fossils, tracing animal movement and evolution, and discovering fossils. Contains reproducible handouts and…

Mineralogical composition of boiler fouling and slagging deposits and their relation to fly ashes: the case of Kardia power plant.

PubMed

Kostakis, George

2011-01-30

Slagging and fouling deposits from a pulverized lignite fired steam generating unit of the Kardia power plant (West Macedonia, Greece) were mineralogically investigated. The structure and cohesion of these deposits varied, usually depending on the level height of the boiler unit where they were formed. Some of the deposits had complex phase composition. The dominant components of the deposits of the burner zone and of the lower and intermediate boiler zones were the amorphous, anhydrite and hematite, while those of the highest levels contained amorphous, and anhydrite. Furthermore, in deposits formed in various other boiler areas gehlenite, anorthite, diopside, quartz, Ca(2)SiO(4), brownmillerite and other crystalline phases were also identified, usually in low amounts or in traces. The major part of the phases constituting the deposits were formed in the boiler, since only a minor part derived from the unreacted minerals present in lignite. Anhydrite was generated from the reaction of SO(2) with CaO formed mainly by the calcination of calcite as well as from dehydration of gypsum contained in lignite, while hematite was produced mainly from the oxidation of pyrite. The calcium-containing silicates formed in the boiler were mainly the products of reactions between CaO and minerals contained in the lignite. Copyright © 2010 Elsevier B.V. All rights reserved.

Long-term geochemical surveillance of fumaroles at Showa-Shinzan dome, Usu volcano, Japan

USGS Publications Warehouse

Symonds, R.B.; Mizutani, Y.; Briggs, P.H.

1996-01-01

This study investigates 31 years of fumarole gas and condensate (trace elements) data from Showa-Shinzan, a dacitic dome-cryptodome complex that formed during the 1943-1945 eruption of Usu volcano. Forty-two gas samples were collected from the highest-temperature fumarole, named A-1, from 1954 (800??C) to 1985 (336??C), and from lower-temperature vents. Condensates were collected contemporaneously with the gas samples, and we reanalyzed ten of these samples, mostly from the A-1 vent, for 32 cations and three anions. Modeling using the thermochemical equilibrium program, SOLVGAS, shows that the gas samples are mild disequilibrium mixtures because they: (a) contain unequilibrated sedimentary CH4 and NH3; (b) have unequilibrated meteoric water; or (c) lost CO, either by air oxidation or by absorption by the sodium hydroxide sampling solution. SOLVGAS also enabled us to restore the samples by removing these disequilibrium effects, and to estimate their equilibrium oxygen fugacities and amounts of S2 and CH4. The restored compositions contain > 98% H2O with minor to trace amounts of CO2, H2, HCl, SO2, HF, H2S, CO, S2 and CH4. We used the restored gas and condensate data to test the hypotheses that these time-series compositional data from the dome's fumaroles provide: (1) sufficient major-gas data to analyze long-term degassing trends of the dome's magma-hydrothermal system without the influence of sampling or contamination effects; (2) independent oxygen fugacity-versus-temperature estimates of the Showa-Shinzan dacite; (3) the order of release of trace elements, especially metals, from magma; and (4) useful information for assessing volcanic hazards. The 1954-1985 restored A-1 gas compositions confirm the first hypothesis because they are sufficient to reveal three long-term degassing trends: (1) they became increasingly H2O-rich with time due to the progressive influx of meteoric water into the dome; (2) their C/S and S/Cl ratios decreased dramatically while their Cl/F ratios stayed roughly constant, indicating the progressive outgassing of less soluble components (F ??? Cl > S > C) from the magma reservoir; and (3) their H2O/H2, CO2/CO and H2S/SO2 ratios increased significantly in concert with equilibrium changes expected for the ??? 500??C temperature drop. When plotted against reciprocal temperature, the restored-gas log oxygen fugacities follow a tight linear trend from 800??C to NNO + 2.5 at ??? 400??C. This trend largely disproves the second hypothesis because the oxygen fugacities for the < 800??C restored gases can only be explained by mixing of hot magmatic gases with ??? 350??C steam from superheated meteoric water. But above 800??C this trend intersects the opposing linear trend for other Usu eruptive products, implying a log oxygen fugacity of -11.45 at 902??C for the Showa-Shinzan magma. The time-series trace-element data also disprove the third hypothesis because rock- and incrustation-particle contaminants in the condensates account for most of the trace-element variation. Nonetheless, highly volatile elements like B and As are relatively unaffected by this particle contamination, and they show similar time-series trends as Cl and F. Finally, except for infrequent sampling around the 1977 Usu eruption, the results generally confirm the fourth hypothesis, since the time-series trends for the major gases and selected trace elements indicate that, with time, the system cooled, degassed and was infiltrated by meteoric water, all of which are positive signs that volcanic activity declined over the 31-year history. This study also suggests that second boiling of shallow magma within and possibly beneath the cryptodome sustained magmatic degassing for at least 20 years after emplacement.

The peculiar geochemical signatures of São Miguel (Azores) lavas: Metasomatised or recycled mantle sources?

NASA Astrophysics Data System (ADS)

Beier, Christoph; Stracke, Andreas; Haase, Karsten M.

2007-07-01

The island of São Miguel, Azores consists of four large volcanic systems that exhibit a large systematic intra-island Sr-Nd-Pb-Hf isotope and trace element variability. The westernmost Sete Cidades volcano has moderately enriched Sr-Nd-Pb-Hf isotope ratios. In contrast, lavas from the easternmost Nordeste volcano have unusually high Sr and Pb and low Nd and Hf isotope ratios suggesting a long-term evolution with high Rb/Sr, U/Pb, Th/Pb, Th/U and low Sm/Nd and Lu/Hf parent-daughter ratios. They have trace element concentrations similar to those of the HIMU islands, with the exception of notably higher alkali element (Cs, Rb, K, Ba) and Th concentrations. The time-integrated parent-daughter element evolution of both the Sete Cidades and Nordeste source matches the incompatibility sequence commonly observed during mantle melting and consequently suggests that the mantle source enrichment is caused by a basaltic melt, either as a metasomatic agent or as recycled oceanic crust. Our calculations show that a metasomatic model involving a small degree basaltic melt is able to explain the isotopic enrichment but, invariably, produces far too enriched trace element signatures. We therefore favour a simple recycling model. The trace element and isotopic signatures of the Sete Cidades lavas are consistent with the presence of ancient recycled oceanic crust that has experienced some Pb loss during sub-arc alteration. The coherent correlation of the parent-daughter ratios (e.g. Rb/Sr, Th/U, U/Pb) and incompatible element ratios (e.g. Nb/Zr, Ba/Rb, La/Nb) with the isotope ratios in lavas from the entire island suggest that the Sete Cidades and Nordeste source share a similar genetic origin. The more enriched trace element and isotopic variations of Nordeste can be reproduced by recycled oceanic crust in the Nordeste source that contains small amounts of evolved lavas (˜ 1-2%), possibly from a subducted seamount. The rare occurrence of enriched source signatures comparable to Nordeste may be taken as circumstantial evidence that stirring processes in the Earth's mantle are not able to homogenise material within the size of seamounts over timescales of mantle recycling.

Petrographic and geochemical contrasts and environmentally significant trace elements in marine-influenced coal seams, Yanzhou mining area, China

USGS Publications Warehouse

Liu, Gaisheng; Yang, P.; Peng, Z.; Chou, C.-L.

2004-01-01

The Yanzhou mining area in west Shandong Province, China contains coals of Permian and Carboniferous age. The 31 and 32 seams of the Permian Shanxi Formation and seams 6, 15-17 of the Carboniferous Taiyuan Formation were analyzed for coal petrology, mineralogy and geochemical parameters. The parameters indicate that the coal is high volatile bituminous in rank. The coal is characterized by high vitrinite and low to medium inertinite and liptinite contents. These properties may be related to evolution of the coal forming environment from more reducing conditions in a marine influenced lower delta plain environment for the early Taiyuan coals to more oxidizing paleoenvironments in an upper delta plain for the upper Shanxi coal seams. The major mineral phases present in the coal are quartz, kaolinite, pyrite and calcite. Sulfur is one of the hazardous elements in coal. The major forms of sulfur in coal are pyritic, organic and sulfate sulfur. Pyritic and organic sulfur generally account for the bulk of the sulfur in coal. Elemental sulfur also occurs in coal, but only in trace to minor amounts. In this paper, the distribution and concentration of sulfur in the Yanzhou mining district are analyzed, and the forms of sulfur are studied. The sulfur content of the Taiyuan coal seams is considerably higher than that of the Shanxi coals. Organic sulfur content is positively correlated to total and pyritic sulfur. The vertical variation of Cu, Zn, Pb, As, Th, U and sulfur contents in coal seam 3 of the Shanxi Formation in the Xinglongzhuang mine show that all these trace elements, with the exception of Th, are enriched in the top and bottom plies of the seam, and that their concentrations are also relatively high in the dirt bands within the seam. The pyritic sulfur is positively correlated with total sulfur, and both are enriched in the top, bottom and parting plies of the seam. The concentrations of the trace elements are closely related to sulfur and ash contents. Most of the trace elements are correlated with the ash content, and may be associated with the mineral matter in the coal. ?? 2004 Elsevier Ltd. All rights reserved.

Reversibility of radiocaesium sorption on illite

NASA Astrophysics Data System (ADS)

de Koning, Arjan; Comans, Rob N. J.

2004-07-01

Adsorption of trace amounts of radiocaesium on NH 4-, K-, and Na-saturated Fithian illite and subsequent desorption by 1 M NH 4 showed that a substantial amount of radiocaesium (44%, 46%, and 91% for NH 4-, K-, and Na-illite, respectively) cannot be desorbed after only 5 min of adsorption. Our results suggest that this instantaneous fixation is caused by the collapse of the frayed edges of the clay mineral and the relatively high concentration of radiocaesium building up in solution in the batch desorption experiments. Consequently, commonly applied high-NH 4 extractions underestimate truly exchangeable amounts of radiocaesium in soils and sediments containing illitic clay minerals. The rate of desorption of trace amounts of radiocaesium from the solids using high NH 4 or Cs concentrations has a half-life of about 2 yr, reflecting radiocaesium desorption from (partially) collapsed interlayers. Extraction of radiocaesium from illite after 5 min of contact time with a Cs-selective adsorbent or a 1 × 10 -6 M CsCl solution shows that 100% of the bound radiocaesium is readily available. The desorption rate in the presence of a Cs-selective adsorbent has a half-life of about 0.2 yr. Desorption of radiocaesium from illite using different ammonium concentrations shows that radiocaesium partitioning follows reversible ion-exchange theory if the NH 4 concentration is below 1 × 10 -4 M, and sufficient time (weeks) is allowed for the reaction to proceed. Thus, radiocaesium sorption reversibility in the natural environment is much higher than generally assumed, and equilibrium solid/liquid partitioning may be assumed for the long-term modelling of radiocaesium mobility in the natural environment. In the particular case of anoxic freshwater sediments with very high NH 4 concentrations in the pore waters (up to several mmol.L -1), collapse of the frayed edges of illite may occur, influencing radiocaesium partitioning. If collapse occurs before radiocaesium adsorbs to illite, high caesium sorption reversibility as measured by high-NH 4 extraction can be expected because further collapse of the frayed edges during the extraction procedure will be limited. This effect has indeed been observed earlier in the extraction of radiocaesium from anoxic freshwater sediments with high-NH 4 solutions and was as yet unexplained.

Residues of organochlorine pesticides, mercury, and PCB's in mourning doves from eastern United States--1970-71

USGS Publications Warehouse

Kreitzer, J.F.

1974-01-01

Mourning dove (Zenaidura macroura) breast muscle samples from birds collected in 1970-71 from Rhode Island, Pennsylvania, Maryland, Missouri, Kentucky, Virginia, Arkansas, Tennessee, North Carolina, South Carolina, Mississippi, Alabama, Georgia, Louisiana, and Florida were found to contain residues of DDT, DDE, DDD, polychlorinated biphenyls, dieldrin, mirex, mercury, and heptachlor epoxide in amounts not considered hazardous to consumers, human or nonhuman. There were 145 birds involved, 7 to 10 from each State. Residues of DDT plus DDE plus DDD averaged 5.83 ppm lipid weight (0.068 ppm wet weight); those of PCB's, 9.75 ppm lipid weight (0.121 ppm wet weight); compounds were found in all birds. Heptachlor epoxide and dieldrin were found in little more than trace amounts: heptachlor in all birds, dieldrin in 73. Mirex was found only in birds from South Carolina, Georgia, and Florida, averaging 4.32 ppm lipid weight (0.046 ppm wet weight) in eight birds. Less than 0.05 ppm (wet weight) mercury was found in all birds except 10, in which it ranged from 0.07 to 0.67 ppm. The 10 were from Rhode Island, Pennsylvania, Maryland, Virginia, Tennessee, and Alabama.

Effects of hydrocarbon contamination on ozone generation with dielectric barrier discharges

NASA Astrophysics Data System (ADS)

Lopez, Jose L.; Vezzu, Guido; Freilich, Alfred; Paolini, Bernhard

2013-08-01

The increasing usage of the feed gases of lower grade liquid oxygen (LOX) containing higher levels of trace hydrocarbon impurities in dielectric barrier discharge (DBD) for ozone generation requires a better understanding of the kinetics of the by-product formation resulting from reactions involving these hydrocarbon impurities. As a case study of hydrocarbon impurities, the kinetics of CH4 conversion in DBDs and the subsequent HNO3 formation were investigated by means of gas-phase plasma diagnostics, supported by detailed process modeling, and extensive in-situ and ex-situ by-product analysis. The by-products formation in the plasma with the presence of CH4, were found to differ significantly in oxygen-fed generators as compared to generators fed with oxygen/nitrogen mixtures. The amount of HNO3 formed depends on the concentration of NOx formed in the plasma and the amount of CH4 that is converted, but not on the O3 concentration. In the present work we have investigated CH4 concentrations of up to 1.95 wt% of the feed gas. The rate of deterioration of the overall ozone generator performance was found to be affected by the concentration of nitrogen in the oxygen/nitrogen mixture.

Test results for fuel cell operation on anaerobic digester gas

NASA Astrophysics Data System (ADS)

Spiegel, R. J.; Preston, J. L.

EPA, in conjunction with ONSI, embarked on a project to define, design, test, and assess a fuel cell energy recovery system for application at anaerobic digester waste water (sewage) treatment plants. Anaerobic digester gas (ADG) is produced at these plants during the process of treating sewage anaerobically to reduce solids. ADG is primarily comprised of methane (57-66%), carbon dioxide (33-39%), nitrogen (1-10%), and a small amount of oxygen (<0.5%). Additionally, ADG contains trace amounts of fuel cell catalyst contaminants consisting of sulfur-bearing compounds (principally hydrogen sulfide) and halogen compounds (chlorides). The project has addressed two major issues: development of a cleanup system to remove fuel cell contaminants from the gas and testing/assessing of a modified ONSI PC25 C fuel cell power plant operating on the cleaned, but dilute, ADG. Results to date demonstrate that the ADG fuel cell power plant can, depending on the energy content of the gas, produce electrical output levels close to full power (200 kW) with measured air emissions comparable to those obtained by a natural gas fuel cell. The cleanup system results show that the hydrogen sulfide levels are reduced to below 10 ppbv and halides to approximately 30 ppbv.

An exploratory investigation of polar organic compounds in waters from a lead–zinc mine and mill complex

USGS Publications Warehouse

Rostad, Colleen E.; Schmitt, Christopher J.; Schumacher, John G.; Leiker, Thomas J.

2011-01-01

Surface water samples were collected in 2006 from a lead mine-mill complex in Missouri to investigate possible organic compounds coming from the milling process. Water samples contained relatively high concentrations of dissolved organic carbon (DOC; greater than 20 mg/l) for surface waters but were colorless, implying a lack of naturally occurring aquatic humic or fulvic acids. Samples were extracted by three different types of solid-phase extraction and analyzed by electrospray ionization/mass spectrometry. Because large amounts of xanthate complexation reagents are used in the milling process, techniques were developed to extract and analyze for sodium isopropyl xanthate and sodium ethyl xanthate. Although these xanthate reagents were not found, trace amounts of the degradates, isopropyl xanthyl thiosulfonate and isopropyl xanthyl sulfonate, were found in most locations sampled, including the tailings pond downstream. Dioctyl sulfosuccinate, a surfactant and process filtering aid, was found at concentrations estimated at 350 μg/l at one mill outlet, but not downstream. Release of these organic compounds downstream from lead-zinc mine and milling areas has not previously been reported. A majority of the DOC remains unidentified.

Conductivity measurements on H 2O-bearing CO 2-rich fluids

DOE PAGES

Capobianco, Ryan M.; Miroslaw S. Gruszkiewicz; Bodnar, Robert J.; ...

2014-09-10

Recent studies report rapid corrosion of metals and carbonation of minerals in contact with carbon dioxide containing trace amounts of dissolved water. One explanation for this behavior is that addition of small amounts of H 2O to CO 2 leads to significant ionization within the fluid, thus promoting reactions at the fluid-solid interface analogous to corrosion associated with aqueous fluids. The extent of ionization in the bulk CO 2 fluid was determined using a flow-through conductivity cell capable of detecting very low conductivities. Experiments were conducted from 298 to 473 K and 7.39 to 20 MPa with H 2O concentrationsmore » up to ~1600 ppmw (xH 2O ≈ 3.9 x 10 -3), corresponding to the H 2O solubility limit in liquid CO 2 at ambient temperature. All solutions showed conductivities <10 nS/cm, indicating that the solutions were essentially ion-free. Furthermore, this observation suggests that the observed corrosion and carbonation reactions are not the result of ionization in CO 2-rich bulk phase, but does not preclude ionization in the fluid at the fluid-solid interface.« less

Arsenic Speciation of Terrestrial Invertebrates

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

Moriarty, M.M.; Koch, I.; Gordon, R.A.

2009-07-01

The distribution and chemical form (speciation) of arsenic in terrestrial food chains determines both the amount of arsenic available to higher organisms, and the toxicity of this metalloid in affected ecosystems. Invertebrates are part of complex terrestrial food webs. This paper provides arsenic concentrations and arsenic speciation profiles for eight orders of terrestrial invertebrates collected at three historical gold mine sites and one background site in Nova Scotia, Canada. Total arsenic concentrations, determined by inductively coupled plasma mass spectrometry (ICP-MS), were dependent upon the classification of invertebrate. Arsenic species were determined by high-performance liquid chromatography (HPLC) ICP-MS and X-ray absorptionmore » spectroscopy (XAS). Invertebrates were found by HPLC ICP-MS to contain predominantly arsenite and arsenate in methanol/water extracts, while XAS revealed that most arsenic is bound to sulfur in vivo. Examination of the spatial distribution of arsenic within an ant tissue highlighted the differences between exogenous and endogenous arsenic, as well as the extent to which arsenic is transformed upon ingestion. Similar arsenic speciation patterns for invertebrate groups were observed across sites. Trace amounts of arsenobetaine and arsenocholine were identified in slugs, ants, and spiders.« less

NARSTO EPA SS ST LOUIS AIR CHEM PM MET DATA

Atmospheric Science Data Center

2018-04-09

... Winds Precipitation Amount Surface Pressure Solar Radiation Surface Air Temperature Particulates Trace Metals ... Earth Related Data:  Environmental Protection Agency Supersites St. Louis SCAR-B Block:  ...

Study on microstructure and strengthening mechanism of AZ91-Y magnesium alloy

NASA Astrophysics Data System (ADS)

Cai, Huisheng; Guo, Feng; Su, Juan; Liu, Liang; Chen, Baodong

2018-03-01

AZ91-Y magnesium alloy with different thicknesses were prepared by die casting process. The main existence forms of Y in alloy and the effects of Y on microstructure and mechanical properties of alloy were studied, the main reason for the change of mechanical properties and fracture mechanism were analyzed. The results show that, yttrium exists mainly in the forms of Al2Y phase and trace solid solution in α-Mg. Yttrium can refine the grain of α-Mg, reduce the amount of eutectic β-Mg17Al12 phase and promote its discrete distribution. The room temperature tensile strength and elongation of alloy increased first and then decreased with the increase of Y content. The designed alloys containing 0.6% Y (measured containing 0.63% Y) have better mechanical properties. The change of mechanical properties of alloy is a comprehensive reflection of the effect of solid solution, grain refinement and second phase. The cracking of Al2Y phase and β-Mg17Al12 phase and crack propagation through Al2Y phase and β-Mg17Al12 phase are the main fracture mechanism of magnesium alloy containing yttrium. The cooling rate does not change the trend of the influence of Y, but affects the degree of influence of Y.

Development of Modeling Approaches for Nuclear Thermal Propulsion Test Facilities

NASA Technical Reports Server (NTRS)

Jones, Daniel R.; Allgood, Daniel C.; Nguyen, Ke

2014-01-01

High efficiency of rocket propul-sion systems is essential for humanity to venture be-yond the moon. Nuclear Thermal Propulsion (NTP) is a promising alternative to conventional chemical rock-ets with relatively high thrust and twice the efficiency of the Space Shuttle Main Engine. NASA is in the pro-cess of developing a new NTP engine, and is evaluat-ing ground test facility concepts that allow for the thor-ough testing of NTP devices. NTP engine exhaust, hot gaseous hydrogen, is nominally expected to be free of radioactive byproducts from the nuclear reactor; how-ever, it has the potential to be contaminated due to off-nominal engine reactor performance. Several options are being investigated to mitigate this hazard potential with one option in particular that completely contains the engine exhaust during engine test operations. The exhaust products are subsequently disposed of between engine tests. For this concept (see Figure 1), oxygen is injected into the high-temperature hydrogen exhaust that reacts to produce steam, excess oxygen and any trace amounts of radioactive noble gases released by off-nominal NTP engine reactor performance. Water is injected to condense the potentially contaminated steam into water. This water and the gaseous oxygen (GO2) are subsequently passed to a containment area where the water and GO2 are separated into separate containment tanks.

Trace metal dynamics in floodplain soils of the river Elbe: a review.

PubMed

Schulz-Zunkel, Christiane; Krueger, Frank

2009-01-01

This paper reviews trace metal dynamics in floodplain soils using the Elbe floodplains in Germany as an example of extraordinary importance because of the pollution level of its sediments and soils. Trace metal dynamics are determined by processes of retention and release, which are influenced by a number of soil properties including pH value, redox potential, organic matter, type and amount of clay minerals, iron-, manganese- and aluminum-oxides. Today floodplains act as important sinks for contaminants but under changing hydraulic and geochemical conditions they may also act as sources for pollutants. In floodplains such changes may be extremes in flooding or dry periods that particularly lead to altered redox potentials and that in turn influence the pH value, the mineralization of organic matter as well as the charge of the pedogenic oxides. Such reactions may affect the bioavailability of trace metals in soils and it can be clearly seen that the bioavailability of metals is an important factor for estimating trace metal remobilization in floodplain soils. However as bioavailability is not a constant factor, there is still a lack of quantification of metal mobilization particularly on the basis of changing geochemical conditions. Moreover, mobile amounts of metals in the soil solution do not indicate to which extent remobilized metals will be transported to water bodies or plants and therefore potentially have toxicological effects. Consequently, floodplain areas still need to be taken into consideration when studying the role and behavior of sediments and soils for transporting pollutants within river systems, particularly concerning the Water Framework Directive.

Exoskeleton Heterogeneity in Crustaceans: Quantifying Compositional and Structural Variations Across Body Parts

NASA Astrophysics Data System (ADS)

Ulrich, R. N.; Mergelsberg, S. T.; Dove, P. M.

2016-12-01

Crustacean exoskeletons are a complex biocomposite of organic macromolecules and calcium carbonate minerals. The highly divergent functions and diverse morphologies of these biominerals across taxa raise the question of whether these differences are systematically reflected in exoskeleton composition and structure. Previous studies that investigated element concentrations in exoskeletons used spectroscopic methods. However, the findings were largely inconclusive because of analytical limitations and most studies concluded that magnesium, phosphorus, and other trace elements are mostly contained in the mineral fraction because concentrations in the organic framework could not be resolved. This experimental study was designed to quantify the distributions of Ca, P, Mg, and Sr in the mineral versus organic fractions of exoskeletons from the American Lobster (H. americanus), Dungeness Crab (M. magister), and Red Rock Crab (M. productus). Samples of exoskeleton from 10 body parts were collected in triplicate and dissolved using three procedures specific to extracting the 1) mineral, 2) protein, and 3) chitin phases separately. Chemical analyses of the resulting effluents using ICP-OES show the mineral fraction of the skeleton can contain significant amounts of mineralized Mg and P particularly for body parts associated with a significant difference in mineral structural ordering. The protein fraction contains more Mg and P than expected based on estimates from previous studies (Hild et al., 2008). While the element distributions vary greatly depending on the location, in body parts with thicker cuticle (e.g. claw) the mineral component appears to control overall composition. The findings have implications for paleoenvironmental reconstructions based upon exoskeleton composition. First, the chemical composition of an exoskeleton cannot be assumed constant across the different body parts of an entire organism. This is particularly true when the exoskeleton of the claw is compared to other body parts. We also show a significant fraction of minor and trace elements contained in an exoskeleton are associated with the organic component. Element concentrations obtained from bulk measurements of exoskeletons cannot be assigned to the mineral fraction without imposing a bias on biomineral composition.

Identification of organically associated trace elements in wood and coal by inductively coupled plasma mass spectrometry.

PubMed

Richaud, R; Lazaro, M J; Lachas, H; Miller, B B; Herod, A A; Dugwell, D R; Kandiyoti, R

2000-01-01

1-Methyl-2-pyrrolidinone (NMP) was used to extract samples of wood (forest residue) and coal; the extracts were analysed by inductively coupled plasma mass spectrometry (ICP-MS) using two different sample preparation methods, in order to identify trace elements associated with the organic part of the samples. A sample of fly ash was similarly extracted and analysed in order to assess the behaviour of the mineral matter contained within the wood and coal samples. 32% of the biomass was extracted at the higher temperature and 12% at room temperature while only 12% of the coal was extracted at the higher temperature and 3% at room temperature. Less than 2% of the ash dissolved at the higher temperature. Size exclusion chromatograms of the extracts indicated the presence of significant amounts of large molecular mass materials (>1000 mu) in the biomass and coal extracts but not in the ash extract. Trace element analyses were carried out using ICP-MS on the acid digests prepared by 'wet ashing' and microwave extraction. Sixteen elements (As, Ba, Be, Cd, Co, Cr, Cu, Ga, Mn, Mo, Ni, Pb, Sb, Se, V and Zn) were quantified, in the samples before extraction, in the extracts and in the residues. Concentrations of trace elements in the original biomass sample were lower than in the coal sample while the concentrations in the ash sample were the highest. The major trace elements in the NMP extracts were Ba, Cu, Mn and Zn from the forest residue; Ba, Cu, Mn, Pb and Zn from the coal; Cu and Zn from the ash. These elements are believed to be associated with the organic extracts from the forest residue and coal, and also from the ash. Be and Sb were not quantified in the extracts because they were present at too low concentrations; up to 40% of Mn was extracted from the biomass sample at 202 degrees C, while Se was totally extracted from the ash sample. For the forest residue, approximately 7% (at room temperature) and 45% (at 202 degrees C) of the total trace elements studied were in the extract; for the coal, approximately 8% (at room temperature) and 23% (at 202 degrees C) were in the extract. For the ash, only 1.4% of the trace elements were extracted at 202 degrees C, comprising 25% of Cd but less than 1% of Pb. Copyright 2000 John Wiley & Sons, Ltd.

A Bayesian model for estimating population means using a link-tracing sampling design.

PubMed

St Clair, Katherine; O'Connell, Daniel

2012-03-01

Link-tracing sampling designs can be used to study human populations that contain "hidden" groups who tend to be linked together by a common social trait. These links can be used to increase the sampling intensity of a hidden domain by tracing links from individuals selected in an initial wave of sampling to additional domain members. Chow and Thompson (2003, Survey Methodology 29, 197-205) derived a Bayesian model to estimate the size or proportion of individuals in the hidden population for certain link-tracing designs. We propose an addition to their model that will allow for the modeling of a quantitative response. We assess properties of our model using a constructed population and a real population of at-risk individuals, both of which contain two domains of hidden and nonhidden individuals. Our results show that our model can produce good point and interval estimates of the population mean and domain means when our population assumptions are satisfied. © 2011, The International Biometric Society.

Geochemical constraints on crustal anatexis: a case study from the Pan-African Damara granitoids of Namibia

NASA Astrophysics Data System (ADS)

McDermott, F.; Harris, N. B. W.; Hawkesworth, C. J.

1996-05-01

Major and trace element models of recently published vapour-absent mica dehydration melting experiments are used to identify granitoids generated by muscovite and biotite dehydration melting, and to distinguish between plagioclase-limited and biotite-limited, biotite dehydration melting. In the case of granitoids from the Pan-African Damara mobile belt (Namibia), many of the leucogranites and Salem-type granitoids may be modelled by biotite dehydration melting. The low Rb/Sr granitoids (e.g. Donkerhuk Onanis, Salem Onanis, Donkerhuk Nomatsaus, Salem Goas) probably reflect feldspar-limited, biotite dehydration melting (a pelitic source) whereas the high Rb/Sr suites (e.g. Bloedkoppie leucogranite, Stinkbank leucogranite, Salem Swakopmund, Leucocratic Stink bank granite) reflect biotite-limited, biotite dehydration melting (a greywacke source). Alaskites from the Damara belt have major element compositions which are consistent with muscovite dehydration melting, and their positive Eu anomalies are linked to high K2O reflecting K-feldspar entrainment. Combined Zr and LREE (light rare earth element) solubility models indicate that insufficient time (probably less than 104 years) had elapsed between melt generation and melt extraction to ensure that the alaskite melts attained their equilibrium concentrations of Zr and the LREEs. In contrast, the leucogranites and Salem-type granites have attained their equilibrium inventories of these trace elements. Combined Fe2O3 and MgO contents in some samples from two granitoids (the Salem Goas and Donkerhuk Onanis intrusions) are higher than those readily attainable by biotite dehydration melting indicating either: (1) that they contain a contribution from melts generated by incipient garnet breakdown or; (2) that they contain small amounts of an entrained ferromagnesian phase.

Inorganic geochemical indicators of glacial-interglacial changes in productivity and anoxia on the California continental margin

USGS Publications Warehouse

Dean, W.E.; Gardner, J.V.; Piper, D.Z.

1997-01-01

Evidence from sediments in cores collected from within the present oxygen-minimum zone (OMZ; 600-1200 m) on the central and northern California margins record several episodes during the last interstadial (OIS-3, ca. 60-24 ka) of deposition of laminated sediments containing elevated concentrations of several trace elements indicative of anoxic conditions (e.g., Mo, Ni, Zn, and Cu). The presence of abundant well-preserved organic matter, as well as lack of bioturbation and the presence of elevated concentrations of Mo and other trace elements, all support the theory that the OMZ in the northeastern Pacific Ocean was more intense, possibly anoxic, at several times during the late Pleistocene. Sediments of all ages in cores from the southern California margin contain elevated concentrations of Mo, suggesting that this area has always had higher rates of sulfate reduction than either the central or northern California areas. Most of the Ba in sediments in all cores collected on the upper continental slope (200-2700 m) off California and southern Oregon is derived from detrital clastic material, and this source did not change much in time. However, the amount of biogenic Ba did vary with time, and these variations closely follow the temporal variations in organic C (Corg) mass accumulation rate. Using Ba and Corg mass accumulation rates as proxy variables for productivity, all cores show that organic productivity under the California Current upwelling system was highest during OIS-3 and the Holocene, and lowest during the last glacial interval (LGI, ca. 24-10 ka). All paleoproductivity proxy variables indicate that the southern California area has always experienced higher productivity than other areas under the California Current, at least over the last 50 ky. Copyright ?? 1997 Elsevier Science Ltd.

Scalable Performance Measurement and Analysis

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

Gamblin, Todd

2009-01-01

Concurrency levels in large-scale, distributed-memory supercomputers are rising exponentially. Modern machines may contain 100,000 or more microprocessor cores, and the largest of these, IBM's Blue Gene/L, contains over 200,000 cores. Future systems are expected to support millions of concurrent tasks. In this dissertation, we focus on efficient techniques for measuring and analyzing the performance of applications running on very large parallel machines. Tuning the performance of large-scale applications can be a subtle and time-consuming task because application developers must measure and interpret data from many independent processes. While the volume of the raw data scales linearly with the number ofmore » tasks in the running system, the number of tasks is growing exponentially, and data for even small systems quickly becomes unmanageable. Transporting performance data from so many processes over a network can perturb application performance and make measurements inaccurate, and storing such data would require a prohibitive amount of space. Moreover, even if it were stored, analyzing the data would be extremely time-consuming. In this dissertation, we present novel methods for reducing performance data volume. The first draws on multi-scale wavelet techniques from signal processing to compress systemwide, time-varying load-balance data. The second uses statistical sampling to select a small subset of running processes to generate low-volume traces. A third approach combines sampling and wavelet compression to stratify performance data adaptively at run-time and to reduce further the cost of sampled tracing. We have integrated these approaches into Libra, a toolset for scalable load-balance analysis. We present Libra and show how it can be used to analyze data from large scientific applications scalably.« less

Surface complexation model of uranyl sorption on Georgia kaolinite

USGS Publications Warehouse

Payne, T.E.; Davis, J.A.; Lumpkin, G.R.; Chisari, R.; Waite, T.D.

2004-01-01

The adsorption of uranyl on standard Georgia kaolinites (KGa-1 and KGa-1B) was studied as a function of pH (3-10), total U (1 and 10 ??mol/l), and mass loading of clay (4 and 40 g/l). The uptake of uranyl in air-equilibrated systems increased with pH and reached a maximum in the near-neutral pH range. At higher pH values, the sorption decreased due to the presence of aqueous uranyl carbonate complexes. One kaolinite sample was examined after the uranyl uptake experiments by transmission electron microscopy (TEM), using energy dispersive X-ray spectroscopy (EDS) to determine the U content. It was found that uranium was preferentially adsorbed by Ti-rich impurity phases (predominantly anatase), which are present in the kaolinite samples. Uranyl sorption on the Georgia kaolinites was simulated with U sorption reactions on both titanol and aluminol sites, using a simple non-electrostatic surface complexation model (SCM). The relative amounts of U-binding >TiOH and >AlOH sites were estimated from the TEM/EDS results. A ternary uranyl carbonate complex on the titanol site improved the fit to the experimental data in the higher pH range. The final model contained only three optimised log K values, and was able to simulate adsorption data across a wide range of experimental conditions. The >TiOH (anatase) sites appear to play an important role in retaining U at low uranyl concentrations. As kaolinite often contains trace TiO2, its presence may need to be taken into account when modelling the results of sorption experiments with radionuclides or trace metals on kaolinite. ?? 2004 Elsevier B.V. All rights reserved.

Trace element release from estuarine sediments of South Mosquito Lagoon near Kennedy Space Center

NASA Technical Reports Server (NTRS)

Menon, M. P.; Ghuman, G. S.; Emeh, C. O.

1979-01-01

Analytical partitioning of four trace metals in estuarine sediments collected from eight sites in South Mosquito Lagoon near Kennedy Space Center, in terms of four different categories was accomplished using four different extraction techniques. The concentrations of the four trace metals, Zn, Mn, Cd, and Cu, released in interstitial water extract, 1 N ammonium acetate extract, conc. HCl extract and fusion extract of sediments as well as their concentrations in water samples collected from the same location were determined using flame atomic absorption technique. From the analytical results the percentages of total amount of each metal distributed among four different categories, interstitial water phase, acetate extractable, acid extractable and detrital crystalline material, were determined. Our results suggest that analytical partitioning of trace metals in estuarine sediments may be used to study the mechanism of incorporation of trace metals with sediments from natural waters. A correlation between the seasonal variation in the concentration of acetate extractable trace metals in the sediment and similar variation in their concentration in water was observed. A mechanism for the release of trace metals from estuarine sediments to natural water is also suggested.

New insights into trace element wet deposition in the Himalayas: amounts, seasonal patterns, and implications.

PubMed

Cong, Zhiyuan; Kang, Shichang; Zhang, Yulan; Gao, Shaopeng; Wang, Zhongyan; Liu, Bin; Wan, Xin

2015-02-01

Our research provides the first complete year-long dataset of wet deposition of trace elements in the high Himalayas based on a total of 42 wet deposition events on the northern slope of Mt. Qomolangma (Everest). Except for typical crustal elements (Al, Fe, and Mn), the concentration level of most trace elements (Sc, V, Cr, Co, Ni, Cu, Zn, As, Mo, Cd, Sn, Cs, Pb, Bi, and U) are generally comparable to those preserved in snow pits and ice cores from the nearby East Rongbuk Glacier. Cadmium was the element most affected by anthropogenic emissions. No pronounced seasonal variations are observed for most trace elements despite different transport pathways. In our study, the composition of wet precipitation reflects a regional background condition and is not clearly related to specific source regions. For the trace element record from ice cores and snow pits in the Himalayas, it could be deduced that the pronounced seasonal patterns were caused by the dry deposition of trace elements (aerosols) during their long exposure to the atmosphere after precipitation events. Our findings are of value for the understanding of the trace element deposition mechanisms in the Himalayas.

Ray tracing: Experience at SRC

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

Severson, M.

1996-09-01

SHADOW [B. Lai and F. Cerrina, Nucl. Instrum. Methods A {bold 246}, 337 (1986)] is the primary ray-tracing program used at SRC. Ray tracing provides a tremendous amount of information regarding beamline layout, mirror sizes, resolution, alignment tolerances, and beam size at various locations. It also provides a way to check the beamline design for errors. Two recent designs have been ray traced extensively: an undulator-based, 4-meter, normal-incidence monochromator (NIM) [R. Reininger, M.C. Severson, R.W.C. Hansen, W.R. Winter, M.A. Green, and W.S. Trzeciak, Rev. Sci. Instrum. {bold 66}, 2194 (1995)] and an undulator-based, plane-grating monochromator (PGM) [R. Reininger, S.L. Crossley,more » M.A. Lagergren, M.C. Severson, and R.W.C. Hansen, Nucl. Instrum. Methods A {bold 347}, 304 (1994)]. {copyright} {ital 1996 American Institute of Physics.}« less

Spectroscopic characterization of digestates obtained from sludge mixed to increasing amounts of fruit and vegetable wastes

NASA Astrophysics Data System (ADS)

Provenzano, Maria Rosaria; Cavallo, Ornella; Malerba, Anna Daniela; Di Maria, Francesco; Ricci, Anna; Gigliotti, Giovanni

2015-04-01

Anaerobic digestion (AD) represents an efficient waste-treatment technology during which microorganisms break down biodegradable material in absence of oxygen yielding a biogas containing methane. The aim of this work was to investigate the transformations occurring in the organic matter during the co-digestion of waste mixed sludge (WMS) with an increasing amount of fruit and vegetable wastes (FVW) in a pilot scale apparatus reproducing a full-scale digester in an existing wastewater treatment plant. Samples comprised: sludge, FVW, sludge mixed with 10-20-30-40% FVW. Ingestates and digestates were analyzed by means of emission fluorescence spectroscopy and FTIR associated to Fourier self deconvolution (FSD) of spectra. With increasing the amount of FVW from 10% to 20% at which percentage biogas production reached the maximum value, FTIR spectra and FSD traces of digestates exhibited a decrease of intensity of peaks assigned to polysaccharides and aliphatics and an increase of peak assigned to aromatics as a result of the biodegradation of rapidly degradable materials and concentration of aromatic recalcitrant compounds. Digestates with 30 and 40% FVW exhibited a relative increase of intensity of peaks assigned to aliphatics likely as a result of the increasing amount of rapidly degradable materials and the consequent reduction of the hydraulic retention time. This may cause inhibition of methanogenesis and accumulation of volatile fatty acids. The highest emission fluorescence intensity was observed for the digestate with 20% FVW confirming the concentration of aromatic recalcitrant compounds in the substrate obtained at the highest biogas production.

Liquid-absorption preconcentrator sampling instrument

DOEpatents

Zaromb, Solomon

1990-01-01

A system for detecting trace concentrations of an analyte in air and includes a preconcentrator for the analyte and an analyte detector. The preconcentrator includes an elongated tubular container in which is disposed a wettable material extending substantially the entire length of the container. One end of the wettable material is continuously wetted with an analyte-sorbing liquid, which flows to the other end of the container. Sample air is flowed through the container in contact with the wetted material for trapping and preconcentrating the traces of analyte in the sorbing liquid, which is then collected at the other end of the container and discharged to the detector. The wetted material may be a wick comprising a bundle of fibers, one end of which is immersed in a reservoir of the analyte-sorbing liquid, or may be a liner disposed on the inner surface of the container, with the sorbing liquid being centrifugally dispersed onto the liner at one end thereof. The container is preferably vertically oriented so that gravity effects the liquid flow.

Liquid-absorption preconcentrator sampling instrument

DOEpatents

Zaromb, S.

1990-12-11

A system is described for detecting trace concentrations of an analyte in air and includes a preconcentrator for the analyte and an analyte detector. The preconcentrator includes an elongated tubular container in which is disposed a wettable material extending substantially the entire length of the container. One end of the wettable material is continuously wetted with an analyte-sorbing liquid, which flows to the other end of the container. Sample air is flowed through the container in contact with the wetted material for trapping and preconcentrating the traces of analyte in the sorbing liquid, which is then collected at the other end of the container and discharged to the detector. The wetted material may be a wick comprising a bundle of fibers, one end of which is immersed in a reservoir of the analyte-sorbing liquid, or may be a liner disposed on the inner surface of the container, with the sorbing liquid being centrifugally dispersed onto the liner at one end thereof. The container is preferably vertically oriented so that gravity effects the liquid flow. 4 figs.

Ion microprobe mass analysis of plagioclase from 'non-mare' lunar samples

NASA Technical Reports Server (NTRS)

Meyer, C., Jr.; Anderson, D. H.; Bradley, J. G.

1974-01-01

The ion microprobe was used to measure the composition and distribution of trace elements in lunar plagioclase, and these analyses are used as criteria in determining the possible origins of some nonmare lunar samples. The Apollo 16 samples with metaclastic texture and high-bulk trace-element contents contain plagioclase clasts with extremely low trace-element contents. These plagioclase inclusions represent unequilibrated relicts of anorthositic, noritic, or troctolitic rocks that have been intermixed as a rock flour into the KREEP-rich matrix of these samples. All of the plagioclase-rich inclusions which were analyzed in the KREEP-rich Apollo 14 breccias were found to be rich in trace elements. This does not seem to be consistent with the interpretation that the Apollo 14 samples represent a pre-Imbrium regolith, because such an ancient regolith should have contained many plagioclase clasts with low trace-element contents more typical of plagioclase from the pre-Imbrium crust. Ion-microprobe analyses for Ba and Sr in large plagioclase phenocrysts in 14310 and 68415 are consistent with the bulk compositions of these rocks and with the known distribution coefficients for these elements. The distribution coefficient for Li (basaltic liquid/plagioclase) was measured to be about 2.

Geologic and mineralogic controls on acid and metal-rich rock drainage in an alpine watershed, Handcart Gulch, Colorado

USGS Publications Warehouse

Bove, Dana J.; Caine, Jonathan S.; Lowers, Heather

2012-01-01

The surface and subsurface geology, hydrothermal alteration, and mineralogy of the Handcart Gulch area was studied using map and drill core data as part of a multidisciplinary approach to understand the hydrology and affects of geology on acid-rock drainage in a mineralized alpine watershed. Handcart Gulch was the locus of intense hydrothermal alteration that affected an area of nearly 3 square kilometers. Hydrothermal alteration and accompanied weak mineralization are spatially and genetically associated with small dacite to low-silica rhyolite stocks and plugs emplaced about 37-36 Ma. Felsic lithologies are commonly altered to a quartz-sericite-pyrite mineral assemblage at the surface, but alteration is more variable in the subsurface, ranging from quartz-sericite-pyrite-dominant in upper core sections to a propylitic variant that is more typical in deeper drill core intervals. Late-stage, hydrothermal argillic alteration [kaolinite and(or) smectite] was superimposed over earlier-formed alteration assemblages in the felsic rocks. Smectite in this late stage assemblage is mostly neoformed resulting from dissolution of chlorite, plagioclase, and minor illite in more weakly altered rocks. Hydrothermally altered amphibolites are characterized by biotitic alteration of amphibole, and subsequent alteration of both primary and secondary biotite to chlorite. Whereas pyrite is present both as disseminations and in small veinlets in the felsic lithologies, it is mostly restricted to small veinlets in the amphibolites. Base-metal sulfides including molybdenite, chalcopyrite, sphalerite, and galena are present in minor to trace amounts in the altered rocks. However, geologic data in conjunction with water geochemical studies indicate that copper mineralization may be present in unknown abundance in two distinct areas. The altered rocks contain an average of 8 weight percent fine pyrite that is largely devoid of metals in the crystal structure, which can be a significant source of trace metals in other areas with acid rock drainage. Thus, elevated base-metal concentrations in the trunk stream and discrete springs in the study area, as determined in previous studies, are likely derived from discrete metal-rich sources, rather than the abundant pyrite veins or disseminations. Pyrite is oxidized in nearly all outcrops examined. Drill core data show that zones of pyrite oxidation range in depth from 100 meters below the surface at higher elevations to just a few meters depth at the lowest elevations in the study area. However, discrete pyrite oxidation zones are present in drill core to depths of several hundred meters below the pervasive near-surface oxidation zones. These deeper discrete oxidation zones, which are present where fresh pyrite predominates, are spatially associated with fractures, small faults, and breccias. Quartz-sericite-pyrite-altered rocks containing unoxidized pyrite likely have the highest acid-generating capacity of all alteration assemblages in the study area. Hydrothermal alteration has left these rocks base-cation leached and thus acid-neutralizing potential is negligible. In contrast, propylitic-altered felsic rocks commonly contain trace to minor calcite and abundant chlorite, which provide some amount of acid-neutralization despite the presence of a few percent pyrite.

Variation in Macro and Trace Elements in Progression of Type 2 Diabetes

PubMed Central

2014-01-01

Macro elements are the minerals of which the body needs more amounts and are more important than any other elements. Trace elements constitute a minute part of the living tissues and have various metabolic characteristics and functions. Trace elements participate in tissue and cellular and subcellular functions; these include immune regulation by humoral and cellular mechanisms, nerve conduction, muscle contractions, membrane potential regulations, and mitochondrial activity and enzyme reactions. The status of micronutrients such as iron and vanadium is higher in type 2 diabetes. The calcium, magnesium, sodium, chromium, cobalt, iodine, iron, selenium, manganese, and zinc seem to be low in type 2 diabetes while elements such as potassium and copper have no effect. In this review, we emphasized the status of macro and trace elements in type 2 diabetes and its advantages or disadvantages; this helps to understand the mechanism, progression, and prevention of type 2 diabetes due to the lack and deficiency of different macro and trace elements. PMID:25162051

Trace-Element Concentrations in Northwest Africa 032

NASA Technical Reports Server (NTRS)

Korotev, R. L.; Jolliff, B. L.; Wang, A.; Gillis, J. J.; Haskin, L. A.; Fagan, T. J.; Taylor, G. J.; Keil, K.

2001-01-01

Trace-element concentrations (INAA) are presented for four samples of the NWA 032 lunar meteorite. The mare basalt has a moderately high Th concentration (1.9 ppm) and a higher Th/REE ratio than any other known mare basalt. Additional information is contained in the original extended abstract.

Three-dimensional radiation transfer modeling in a dicotyledon leaf

NASA Astrophysics Data System (ADS)

Govaerts, Yves M.; Jacquemoud, Stéphane; Verstraete, Michel M.; Ustin, Susan L.

1996-11-01

The propagation of light in a typical dicotyledon leaf is investigated with a new Monte Carlo ray-tracing model. The three-dimensional internal cellular structure of the various leaf tissues, including the epidermis, the palisade parenchyma, and the spongy mesophyll, is explicitly described. Cells of different tissues are assigned appropriate morphologies and contain realistic amounts of water and chlorophyll. Each cell constituent is characterized by an index of refraction and an absorption coefficient. The objective of this study is to investigate how the internal three-dimensional structure of the tissues and the optical properties of cell constituents control the reflectance and transmittance of the leaf. Model results compare favorably with laboratory observations. The influence of the roughness of the epidermis on the reflection and absorption of light is investigated, and simulation results confirm that convex cells in the epidermis focus light on the palisade parenchyma and increase the absorption of radiation.

Statistical Evaluation and Optimization of Factors Affecting the Leaching Performance of Copper Flotation Waste

PubMed Central

Çoruh, Semra; Elevli, Sermin; Geyikçi, Feza

2012-01-01

Copper flotation waste is an industrial by-product material produced from the process of manufacturing copper. The main concern with respect to landfilling of copper flotation waste is the release of elements (e.g., salts and heavy metals) when in contact with water, that is, leaching. Copper flotation waste generally contains a significant amount of Cu together with trace elements of other toxic metals, such as Zn, Co, and Pb. The release of heavy metals into the environment has resulted in a number of environmental problems. The aim of this study is to investigate the leaching characteristics of copper flotation waste by use of the Box-Behnken experimental design approach. In order to obtain the optimized condition of leachability, a second-order model was examined. The best leaching conditions achieved were as follows: pH = 9, stirring time = 5 min, and temperature = 41.5°C. PMID:22629194

Statistical evaluation and optimization of factors affecting the leaching performance of copper flotation waste.

PubMed

Coruh, Semra; Elevli, Sermin; Geyikçi, Feza

2012-01-01

Copper flotation waste is an industrial by-product material produced from the process of manufacturing copper. The main concern with respect to landfilling of copper flotation waste is the release of elements (e.g., salts and heavy metals) when in contact with water, that is, leaching. Copper flotation waste generally contains a significant amount of Cu together with trace elements of other toxic metals, such as Zn, Co, and Pb. The release of heavy metals into the environment has resulted in a number of environmental problems. The aim of this study is to investigate the leaching characteristics of copper flotation waste by use of the Box-Behnken experimental design approach. In order to obtain the optimized condition of leachability, a second-order model was examined. The best leaching conditions achieved were as follows: pH = 9, stirring time = 5 min, and temperature = 41.5 °C.

Vertical flow chemical detection portal

DOEpatents

Linker, K.L.; Hannum, D.W.; Conrad, F.J.

1999-06-22

A portal apparatus is described for screening objects or persons for the presence of trace amounts of chemical substances such as illicit drugs or explosives. The apparatus has a test space, in which a person may stand, defined by two generally upright sides spanned by a horizontal transom. One or more fans in the transom generate a downward air flow (uni-directional) within the test space. The air flows downwardly from a high pressure upper zone, past the object or person to be screened. Air moving past the object dislodges from the surface thereof both volatile and nonvolatile particles of the target substance. The particles are entrained into the air flow which continues flowing downward to a lower zone of reduced pressure, where the particle-bearing air stream is directed out of the test space and toward preconcentrator and detection components. The sides of the portal are specially configured to partially contain and maintain the air flow. 3 figs.

Vertical flow chemical detection portal

DOEpatents

Linker, Kevin L.; Hannum, David W.; Conrad, Frank James

1999-01-01

A portal apparatus for screening objects or persons for the presence of trace amounts of chemical substances such as illicit drugs or explosives. The apparatus has a test space, in which a person may stand, defined by two generally upright sides spanned by a horizontal transom. One or more fans in the transom generate a downward air flow (uni-directional) within the test space. The air flows downwardly from a high pressure upper zone, past the object or person to be screened. Air moving past the object dislodges from the surface thereof both volatile and nonvolatile particles of the target substance. The particles are entrained into the air flow which continues flowing downward to a lower zone of reduced pressure, where the particle-bearing air stream is directed out of the test space and toward preconcentrator and detection components. The sides of the portal are specially configured to partially contain and maintain the air flow.

Detection and differentiation of biological species using microcalorimetric spectroscopy.

PubMed

Arakawa, E T; Lavrik, N V; Rajic, S; Datskos, P G

2003-01-01

We report on the application of infrared (IR) microcalorimetric spectroscopy ( micro -CalSpec) to the identification and detection of trace amounts of biological species. Our approach combines principles of photothermal IR spectroscopy with ultrasensitive microcantilever (MC) thermal detectors. We have obtained photothermal IR spectra for DNA and RNA bases and for Bacillus Cereus (an anthrax simulant) in the wavelength range of 2.5-14.5 micro m (4000-690 cm(-1)). The measurements are accomplished by absorbing biological materials directly on a MC thermal detector. The main advantage of the developed micro -CalSpec is its unprecedented sensitivity as compared to any of the previously explored IR techniques, including FTIR and photothermal FTIR methods. Our results demonstrate that <10(-9)g of a biological sample is sufficient to obtain its characteristic micro -CalSpec spectrum that contains information-rich chemical (vibrational) signatures. This opens up a new opportunity to create inexpensive high-throughput analytical systems for biochemical detection.

Mortality of sea lions along the central California coast linked to a toxic diatom bloom.

PubMed

Scholin, C A; Gulland, F; Doucette, G J; Benson, S; Busman, M; Chavez, F P; Cordaro, J; DeLong, R; De Vogelaere, A; Harvey, J; Haulena, M; Lefebvre, K; Lipscomb, T; Loscutoff, S; Lowenstine, L J; Marin, R; Miller, P E; McLellan, W A; Moeller, P D; Powell, C L; Rowles, T; Silvagni, P; Silver, M; Spraker, T; Trainer, V; Van Dolah, F M

2000-01-06

Over 400 California sea lions (Zalophus californianus) died and many others displayed signs of neurological dysfunction along the central California coast during May and June 1998. A bloom of Pseudo-nitzschia australis (diatom) was observed in the Monterey Bay region during the same period. This bloom was associated with production of domoic acid (DA), a neurotoxin that was also detected in planktivorous fish, including the northern anchovy (Engraulis mordax), and in sea lion body fluids. These and other concurrent observations demonstrate the trophic transfer of DA resulting in marine mammal mortality. In contrast to fish, blue mussels (Mytilus edulus) collected during the DA outbreak contained no DA or only trace amounts. Such findings reveal that monitoring of mussel toxicity alone does not necessarily provide adequate warning of DA entering the food web at levels sufficient to harm marine wildlife and perhaps humans.

Atmospheric Pressure Chemical Ionization Sources Used in The Detection of Explosives by Ion Mobility Spectrometry

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

Waltman, Melanie J.

2010-05-01

Explosives detection is a necessary and wide spread field of research. From large shipping containers to airline luggage, numerous items are tested for explosives every day. In the area of trace explosives detection, ion mobility spectrometry (IMS) is the technique employed most often because it is a quick, simple, and accurate way to test many items in a short amount of time. Detection by IMS is based on the difference in drift times of product ions through the drift region of an IMS instrument. The product ions are created when the explosive compounds, introduced to the instrument, are chemically ionizedmore » through interactions with the reactant ions. The identity of the reactant ions determines the outcomes of the ionization process. This research investigated the reactant ions created by various ionization sources and looked into ways to manipulate the chemistry occurring in the sources.« less

PCR method of detecting pork in foods for verifying allergen labeling and for identifying hidden pork ingredients in processed foods.

PubMed

Tanabe, Soichi; Miyauchi, Eiji; Muneshige, Akemi; Mio, Kazuhiro; Sato, Chikara; Sato, Masahiko

2007-07-01

A PCR method to detect porcine DNA was developed for verifying the allergen labeling of foods and for identifying hidden pork ingredients in processed foods. The primer pair, F2/R1, was designed to detect the gene encoding porcine cytochrome b for the specific detection of pork with high sensitivity. The amplified DNA fragment (130 bp) was specifically detected from porcine DNA, while no amplification occurred with other species such as cattle, chicken, sheep, and horse. When the developed PCR method was used for investigating commercial food products, porcine DNA was clearly detected in those containing pork in the list of ingredients. In addition, 100 ppb of pork in heated gyoza (pork and vegetable dumpling) could be detected by this method. This method is rapid, specific and sensitive, making it applicable for detecting trace amounts of pork in processed foods.

Celiac disease treatment: gluten-free diet and beyond.

PubMed

Mäki, Markku

2014-07-01

The basis for celiac disease (CD) treatment is a strict lifelong gluten-free diet. On the diet, the small intestinal mucosal injury heals and gluten-induced symptoms and signs disappear. The mucosal healing is a prerequisite for sustaining health and is also obtained with a diet containing oats and trace amounts of gluten, industrially purified wheat starch-based gluten-free products. The small intestinal mucosa does not heal in noncompliant people, nor when a patient is inadvertently ingesting gluten. Development of adjunctive or alternative therapies is on its way. There are several novel treatment pipelines within academy and industry. Examples are the ideas of using glutenases as a drug to degrade the ingested gluten, polymers to bind and sequester the gluten to the feces, and also vaccine development for an immunotherapy to induce tolerance towards gluten. Clinical drug trials are to be foreseen in CD, soon also in children.

Chromatographic separation of radioactive noble gases from xenon

NASA Astrophysics Data System (ADS)

Akerib, D. S.; Araújo, H. M.; Bai, X.; Bailey, A. J.; Balajthy, J.; Beltrame, P.; Bernard, E. P.; Bernstein, A.; Biesiadzinski, T. P.; Boulton, E. M.; Bramante, R.; Cahn, S. B.; Carmona-Benitez, M. C.; Chan, C.; Chiller, A. A.; Chiller, C.; Coffey, T.; Currie, A.; Cutter, J. E.; Davison, T. J. R.; Dobi, A.; Dobson, J. E. Y.; Druszkiewicz, E.; Edwards, B. N.; Faham, C. H.; Fiorucci, S.; Gaitskell, R. J.; Gehman, V. M.; Ghag, C.; Gibson, K. R.; Gilchriese, M. G. D.; Hall, C. R.; Hanhardt, M.; Haselschwardt, S. J.; Hertel, S. A.; Hogan, D. P.; Horn, M.; Huang, D. Q.; Ignarra, C. M.; Ihm, M.; Jacobsen, R. G.; Ji, W.; Kamdin, K.; Kazkaz, K.; Khaitan, D.; Knoche, R.; Larsen, N. A.; Lee, C.; Lenardo, B. G.; Lesko, K. T.; Lindote, A.; Lopes, M. I.; Manalaysay, A.; Mannino, R. L.; Marzioni, M. F.; McKinsey, D. N.; Mei, D.-M.; Mock, J.; Moongweluwan, M.; Morad, J. A.; Murphy, A. St. J.; Nehrkorn, C.; Nelson, H. N.; Neves, F.; O'Sullivan, K.; Oliver-Mallory, K. C.; Palladino, K. J.; Pease, E. K.; Pech, K.; Phelps, P.; Reichhart, L.; Rhyne, C.; Shaw, S.; Shutt, T. A.; Silva, C.; Solovov, V. N.; Sorensen, P.; Stephenson, S.; Sumner, T. J.; Szydagis, M.; Taylor, D. J.; Taylor, W.; Tennyson, B. P.; Terman, P. A.; Tiedt, D. R.; To, W. H.; Tripathi, M.; Tvrznikova, L.; Uvarov, S.; Verbus, J. R.; Webb, R. C.; White, J. T.; Whitis, T. J.; Witherell, M. S.; Wolfs, F. L. H.; Yazdani, K.; Young, S. K.; Zhang, C.

2018-01-01

The Large Underground Xenon (LUX) experiment operates at the Sanford Underground Research Facility to detect nuclear recoils from the hypothetical Weakly Interacting Massive Particles (WIMPs) on a liquid xenon target. Liquid xenon typically contains trace amounts of the noble radioactive isotopes 85Kr and 39Ar that are not removed by the in situ gas purification system. The decays of these isotopes at concentrations typical of research-grade xenon would be a dominant background for a WIMP search experiment. To remove these impurities from the liquid xenon, a chromatographic separation system based on adsorption on activated charcoal was built. 400 kg of xenon was processed, reducing the average concentration of krypton from 130 ppb to 3.5 ppt as measured by a cold-trap assisted mass spectroscopy system. A 50 kg batch spiked to 0.001 g/g of krypton was processed twice and reduced to an upper limit of 0.2 ppt.

Catalytic conversion wood syngas to synthetic aviation turbine fuels over a multifunctional catalyst.

PubMed

Yan, Qiangu; Yu, Fei; Liu, Jian; Street, Jason; Gao, Jinsen; Cai, Zhiyong; Zhang, Jilei

2013-01-01

A continuous process involving gasification, syngas cleaning, and Fischer-Tropsch (FT) synthesis was developed to efficiently produce synthetic aviation turbine fuels (SATFs). Oak-tree wood chips were first gasified to syngas over a commercial pilot plant downdraft gasifier. The raw wood syngas contains about 47% N(2), 21% CO, 18% H(2), 12% CO(2,) 2% CH(4) and trace amounts of impurities. A purification reaction system was designed to remove the impurities in the syngas such as moisture, oxygen, sulfur, ammonia, and tar. The purified syngas meets the requirements for catalytic conversion to liquid fuels. A multi-functional catalyst was developed and tested for the catalytic conversion of wood syngas to SATFs. It was demonstrated that liquid fuels similar to commercial aviation turbine fuels (Jet A) was successfully synthesized from bio-syngas. Copyright © 2012 Elsevier Ltd. All rights reserved.

Material Utilization of Organic Residues.

PubMed

Peinemann, Jan Christoph; Pleissner, Daniel

2018-02-01

Each year, 1.3 billion tons of food waste is generated globally. This waste traces back to industrial and agricultural producers, bakeries, restaurants, and households. Furthermore, lignocellulosic materials, including grass clippings, leaves, bushes, shrubs, and woods, appear in large amounts. Depending on the region, organic waste is either composted, burned directly, or converted into biogas. All of the options set aside the fact that organic residues are valuable resources containing carbohydrates, lipids, proteins, and phosphorus. Firstly, it is clear that avoidance of organic residues is imperative. However, the residues that accumulate nonetheless should be utilized by material means before energy production is targeted. This review presents different processes for the microbial utilization of organic residues towards compounds that are of great importance for the bioeconomy. The focus thereby is on the challenges coming along with downstream processing when the utilization of organic residues is carried out decentralized. Furthermore, a future process for producing lactic acid from organic residues is sketched.

Analysis of seed oils containing cyclopentenyl fatty acids by combined chromatographic procedures.

PubMed

Christie, W W; Brechany, E Y; Shukla, V K

1989-02-01

The fatty acids of seed oils of the Flacourtiaceae, Hydnocarpus anthelmintica, Caloncoba echinata and Taraktogenus kurzii, have been examined by a combination of capillary gas chromatography, silver ion high performance liquid chromatography and gas chromatography-mass spectrometry. In addition to the common range of cyclopentenyl fatty acids found in such oils, 13-cyclopent-2-enyltridec-4-enoic acid was a major component of H. anthelmintica and was identified by mass spectrometry as its picolinyl ester and dimethyldisulphide adduct. It has not previously been found in nature. In the other seed oils, the isolated double bond in the corresponding fatty acid was in position 6, as expected. Similarly, cis-4-hexadecenoic acid and C16 and C18 cyclopentyl fatty acids were identified for the first time in H. anthelmintica. Iso- and anteiso-methylbranched fatty acids were present in trace amounts.

Chromatographic separation of radioactive noble gases from xenon

DOE PAGES

Akerib, DS; Araújo, HM; Bai, X; ...

2017-10-31

The Large Underground Xenon (LUX) experiment operates at the Sanford Underground Research Facility to detect nuclear recoils from the hypothetical Weakly Interacting Massive Particles (WIMPs) on a liquid xenon target. Liquid xenon typically contains trace amounts of the noble radioactive isotopesmore » $$^{85}$$Kr and $$^{39}$$Ar that are not removed by the in situ gas purification system. The decays of these isotopes at concentrations typical of research-grade xenon would be a dominant background for a WIMP search exmperiment. To remove these impurities from the liquid xenon, a chromatographic separation system based on adsorption on activated charcoal was built. 400 kg of xenon was processed, reducing the average concentration of krypton from 130 ppb to 3.5 ppt as measured by a cold-trap assisted mass spectroscopy system. A 50 kg batch spiked to 0.001 g/g of krypton was processed twice and reduced to an upper limit of 0.2 ppt.« less

Micro-polarimeter for high performance liquid chromatography

DOEpatents

Yeung, Edward E.; Steenhoek, Larry E.; Woodruff, Steven D.; Kuo, Jeng-Chung

1985-01-01

A micro-polarimeter interfaced with a system for high performance liquid chromatography, for quantitatively analyzing micro and trace amounts of optically active organic molecules, particularly carbohydrates. A flow cell with a narrow bore is connected to a high performance liquid chromatography system. Thin, low birefringence cell windows cover opposite ends of the bore. A focused and polarized laser beam is directed along the longitudinal axis of the bore as an eluent containing the organic molecules is pumped through the cell. The beam is modulated by air gap Faraday rotators for phase sensitive detection to enhance the signal to noise ratio. An analyzer records the beams's direction of polarization after it passes through the cell. Calibration of the liquid chromatography system allows determination of the quantity of organic molecules present from a determination of the degree to which the polarized beam is rotated when it passes through the eluent.

Metabolism and tissue distribution of trace elements in broiler chickens' fed diets containing deficient and plethoric levels of copper, manganese, and zinc.

PubMed

Mondal, Sovik; Haldar, Sudipto; Saha, Pinaki; Ghosh, Tapan Kumar

2010-11-01

Supplementation of broiler diets with copper, manganese, and zinc at levels higher than that stipulated by the National Research Council 1994 reportedly improved live weight, feed conversion, and cured leg abnormality supposedly caused by inadequate intake of Mn and Zn. The objective of the study was to ascertain the effects of plethoric supplementation of copper (Cu), manganese (Mn), and zinc (Zn) on performance and metabolic responses in broiler chickens. The study also aimed to discriminate the responses of the birds when the mineral elements were supplemented either in an inorganic or in an organic form. Cobb 400 broiler chickens (1-day old, n = 300) were assigned to three dietary treatments each containing nine replicates with ten birds for 39 days. The treatments included a control in which the diet was devoid of supplemental trace elements and treatments supplemented with an inorganic trace element premix (ITM) and supplemented with a combination of the inorganic and an organic trace element premix (OTM). The ITM contained (per kilogram) copper, 15 g; iron, 90 g; manganese, 90 g; zinc, 80 g (all as sulfated salts); iodine (as potassium iodide), 2 g; and selenium (as sodium selenite), 0.3 g. The OTM on the other hand, contained copper, 2.5 g; iron, 15 g; manganese, 15 g; zinc, 13.33 g; and chromium, 0.226 g (all as protein chelates). Plethoric supplementation of trace elements improved live weight gain and feed/gain ratio (p < 0.05). Leg abnormality developed in the 16% of the control group of birds but not in the supplemented group. Metabolizability of dry matter, organic matter, and protein was higher (p < 0.01) in the ITM and OTM groups. Excretion of Cu, Fe, and Zn decreased (p < 0.1) due to supplementation of the trace elements leading to increased apparent absorption of the said mineral elements (p < 0.01). Concentration of the concerned trace elements in serum, liver, and composite muscle samples was higher (p < 0.05) in the ITM and OTM dietary groups indicating an increased deposition of the said mineral elements due to supplementation. Although the study revealed subtle difference between the inorganic and organic mineral premixes with regards to the parameters mentioned above, it became apparent that it is possible to reduce excretion of these trace elements by a judicious escalation in the level of supplementation. The results of the present investigation further revealed that the trace mineral requirement of broiler chickens suggested by the National Research Council may not be optimum to support the maximum growth potential of the high yielding strains, and it is reasonable to consider a review of the current NRC recommendations to meet the needs of the modern birds.

Ancient Oceans Had Less Oxygen

ERIC Educational Resources Information Center

King, Angela G.

2004-01-01

The amount of dissolved oxygen in the oceans in the mid-Proterozoic period has evolutionary implications since essential trace metals are redox sensitive. The findings suggest that there is global lack of oxygen in seawater.

Premature Craniosynostosis: A Complication of Thyroid Replacement Therapy

ERIC Educational Resources Information Center

Penfold, James L.; Simpson, Donald A.

1975-01-01

Presented are case studies of 3 children, infancy to 9-years-old, whose premature skull ossification (craniosynostosis) is traced to iatrogenic hyperthyroidism from the administration of excessive amounts of thyroid hormone. (CL)

Simple circular odor chart for characterization of trace amounts of odorants discharged from thirteen odor sources

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

Hoshika, Y.; Nihei, Y.; Muto, G.

1981-04-01

A simple circular odor chart is proposed for the explanation of the relationship between sensory responses (to odor quality and intensity) to odors and chemical analysis data of the odorants responsible for each odor discharged from thirteen odor sources. The odorants were classified into eight odorant groups and were analyzed by a systematic gas chromatographic (GC) technique. The characterization of the trace amounts of the odorants was carried out by using the values of a new proposed unit (pOU) based on the ratio of detected concentration to recognition threshold value. The calculated pOU values of the eight groups were plottedmore » in circular charts. It was found that the shape and size of each circular odor chart represent the quality and the intensity of each odor.« less

Electrochemical Impedance Sensors for Monitoring Trace Amounts of NO3 in Selected Growing Media.

PubMed

Ghaffari, Seyed Alireza; Caron, William-O; Loubier, Mathilde; Normandeau, Charles-O; Viens, Jeff; Lamhamedi, Mohammed S; Gosselin, Benoit; Messaddeq, Younes

2015-07-21

With the advent of smart cities and big data, precision agriculture allows the feeding of sensor data into online databases for continuous crop monitoring, production optimization, and data storage. This paper describes a low-cost, compact, and scalable nitrate sensor based on electrochemical impedance spectroscopy for monitoring trace amounts of NO3- in selected growing media. The nitrate sensor can be integrated to conventional microelectronics to perform online nitrate sensing continuously over a wide concentration range from 0.1 ppm to 100 ppm, with a response time of about 1 min, and feed data into a database for storage and analysis. The paper describes the structural design, the Nyquist impedance response, the measurement sensitivity and accuracy, and the field testing of the nitrate sensor performed within tree nursery settings under ISO/IEC 17025 certifications.

Electrochemical Impedance Sensors for Monitoring Trace Amounts of NO3 in Selected Growing Media

PubMed Central

Ghaffari, Seyed Alireza; Caron, William-O.; Loubier, Mathilde; Normandeau, Charles-O.; Viens, Jeff; Lamhamedi, Mohammed S.; Gosselin, Benoit; Messaddeq, Younes

2015-01-01

With the advent of smart cities and big data, precision agriculture allows the feeding of sensor data into online databases for continuous crop monitoring, production optimization, and data storage. This paper describes a low-cost, compact, and scalable nitrate sensor based on electrochemical impedance spectroscopy for monitoring trace amounts of NO3− in selected growing media. The nitrate sensor can be integrated to conventional microelectronics to perform online nitrate sensing continuously over a wide concentration range from 0.1 ppm to 100 ppm, with a response time of about 1 min, and feed data into a database for storage and analysis. The paper describes the structural design, the Nyquist impedance response, the measurement sensitivity and accuracy, and the field testing of the nitrate sensor performed within tree nursery settings under ISO/IEC 17025 certifications. PMID:26197322

Solid phase extraction of trace amounts of Ag, Cd, Cu, and Zn in environmental samples using magnetic nanoparticles coated by 3-(trimethoxysilyl)-1-propantiol and modified with 2-amino-5-mercapto-1,3,4-thiadiazole and their determination by ICP-OES.

PubMed

Mashhadizadeh, Mohammad Hossein; Karami, Zahra

2011-06-15

A fast, sensitive, and simple method using magnetic nanoparticles (MNPs) coated by 3-(trimethoxysilyl)-1-propantiol and modified with 2-amino-5-mercapto-1,3,4-thiadiazole, as an adsorbent has been successfully developed for extraction, preconcentration, and determination of trace amounts of Ag, Cd, Cu, and Zn from environmental samples. The prepared nanoparticles were characterized by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). These magnetic nanoparticles can be easily dispersed in aqueous samples and retrieved by the application of external magnetic field via a piece of permanent magnet. The main factors affecting the extraction efficiency such as pH value, sample volume, eluent concentration and volume, ultrasonication time, and coexisting ions have been investigated and established. Under the optimal conditions, high concentration factors (194, 190, 170, and 182) were achieved for Ag, Cd, Cu, and Zn with relative standard deviations of 5.31%, 4.03%, 3.62%, and 4.20%, respectively. The limits of detection for Ag, Cd, Cu, and Zn were as low as 0.12, 0.12, 0.13 and 0.11 ng mL(-1). The prepared sorbent was applied for preconcentration of trace amounts of Ag, Cd, Cu, and Zn in the various water samples with satisfactory results. Copyright © 2011 Elsevier B.V. All rights reserved.

Performance Data Gathering and Representation from Fixed-Size Statistical Data

NASA Technical Reports Server (NTRS)

Yan, Jerry C.; Jin, Haoqiang H.; Schmidt, Melisa A.; Kutler, Paul (Technical Monitor)

1997-01-01

The two commonly-used performance data types in the super-computing community, statistics and event traces, are discussed and compared. Statistical data are much more compact but lack the probative power event traces offer. Event traces, on the other hand, are unbounded and can easily fill up the entire file system during program execution. In this paper, we propose an innovative methodology for performance data gathering and representation that offers a middle ground. Two basic ideas are employed: the use of averages to replace recording data for each instance and 'formulae' to represent sequences associated with communication and control flow. The user can trade off tracing overhead, trace data size with data quality incrementally. In other words, the user will be able to limit the amount of trace data collected and, at the same time, carry out some of the analysis event traces offer using space-time views. With the help of a few simple examples, we illustrate the use of these techniques in performance tuning and compare the quality of the traces we collected with event traces. We found that the trace files thus obtained are, indeed, small, bounded and predictable before program execution, and that the quality of the space-time views generated from these statistical data are excellent. Furthermore, experimental results showed that the formulae proposed were able to capture all the sequences associated with 11 of the 15 applications tested. The performance of the formulae can be incrementally improved by allocating more memory at runtime to learn longer sequences.

The capability of satellite borne remote sensors to measure stratospheric trace constituents. Volume 3: Supporting material

NASA Technical Reports Server (NTRS)

Keitz, E. L.

1978-01-01

Contained in this volume is material of a supportive nature not considered to be of sufficient importance to be included in the other two previous volumes. This material is of two types:(1) information and numerical evaluations used in the development of mission evaluations for stratospheric trace constituent measurement;and (2) various spatial and temporal distributions for those stratospheric trace species having sufficient measurements available to warrant their presentation.

Metallic contamination of food during preparation and storage: development of methods and some preliminary results.

PubMed

Samsahl, K; Wester, P O

1977-09-01

A chemical procedure for studying trace metals leached from metallic cooking utensils and preserving cans used in the preparation and storage of food has been developed. The method consists in the destruction of the major part of organic matter with HNO3-vapour followed by a complete mineralization of residues with small amounts of HNO3 in Teflon bombs at 150-160 degrees C under a pressure of 3-12 kg/cm2, depending on the amount and composition of the samples. Subsequently, an ion-exchange step removes major components and concentrates the trace elements in a dilute HNO3-solution, suitable for analysis. The ion-exchange separation, which is performed with an automatic ion-exchange separator, is practically free from blank level problems, e.g., typically a mean of less than 2 per cent of the sample levels of the elements being determined. Preliminary results show that large amounts of aluminium are released from vessels to the water during boiling at the same pH-range which exist for most drinking water in Sweden.

Petrogenesis of voluminous mid-Tertiary ignimbrites of the Sierra Madre Occidental, Chihuahua, Mexico

NASA Astrophysics Data System (ADS)

Cameron, Maryellen; Bagby, William C.; Cameron, Kenneth L.

1980-10-01

The mid-Tertiary ignimbrites of the Sierra Madre Occidental of western Mexico constitute the largest continuous rhyolitic province in the world. The rhyolites appear to represent part of a continental magmatic arc that was emplaced when an eastward-dipping subduction zone was located beneath western Mexico. In the Batopilas region of the northern Sierra Madre Occidental the mid-Tertiary Upper Volcanic sequence is composed predominantly of rhyolitic ignimbrites, but volumetrically minor lava flows as mafic as basaltic andesite are also present. The basaltic andesite to rhyolite series is calc-alkalic and contains ˜1% K2O at 60% SiO2. Trace element abundances of a typical ignimbrite with 73% SiO2 are Sr ˜ 225 ppm, Rb ˜130 ppm, Y ˜32 ppm, Th ˜12 ppm, Zr ˜200 ppm, and Nb ˜15 ppm. The entire series plots as coherent and continuous trends on variation diagrams involving major and trace elements, and the trends are distinct from those of geographicallyassociated rocks of other suites. We interpret these and other geochemical variations to indicate that the rocks are comagmatic. Mineral chemistry, Sr isotopic data, and REE modelling support this interpretation. Least squares calculations show that the major element variations are consistent with formation of the basaltic andesite to rhyolite series by crystal fractionation of observed phenocryst phases in approximate modal proportions. In addition, calculations modelling the behavior of Sr with the incompatible trace element Th favor a fractional crystallization origin over a crustal anatexis origin for the rock series. The fractionating minerals included plagioclase (> 50%), and lesser amounts of Fe-Ti oxides, pyroxenes, and/or hornblende. The voluminous ignimbrites represent no more than 20% of the original mass of a mantle-derived mafic parental magma.

Geochemical evidence for African dust and volcanic ash inputs to terra rossa soils on carbonate reef terraces, northern Jamaica, West Indies

USGS Publications Warehouse

Muhs, D.R.; Budahn, J.R.

2009-01-01

The origin of red or reddish-brown, clay-rich, "terra rossa" soils on limestone has been debated for decades. A traditional qualitative explanation for their formation has been the accumulation of insoluble residues as the limestone is progressively dissolved over time. However, this mode of formation often requires unrealistic or impossible amounts of carbonate dissolution. Therefore, where this mechanism is not viable and where local fluvial or colluvial inputs can be ruled out, an external source or sources must be involved in soil formation. On the north coast of the Caribbean island of Jamaica, we studied a sequence of terra rossa soils developed on emergent limestones thought to be of Quaternary age. The soils become progressively thicker, redder, more Fe- and Al-rich and Si-poor with elevation. Furthermore, although kaolinite is found in all the soils, the highest and oldest soils also contain boehmite. Major and trace element geochemistry shows that the host limestones and local igneous rocks are not likely source materials for the soils. Other trace elements, including the rare earth elements (REE), show that tephra from Central American volcanoes is not a likely source either. However, trace element geochemistry shows that airborne dust from Africa plus tephra from the Lesser Antilles island arc are possible source materials for the clay-rich soils. A third, as yet unidentified, source may also contribute to the soils. We hypothesize that older, more chemically mature Jamaican bauxites may have had a similar origin. The results add to the growing body of evidence of the importance of multiple parent materials, including far-traveled dust, to soil genesis.

Impact of acid mine drainages on surficial waters of an abandoned mining site.

PubMed

García-Lorenzo, M L; Marimón, J; Navarro-Hervás, M C; Pérez-Sirvent, C; Martínez-Sánchez, M J; Molina-Ruiz, José

2016-04-01

Weathering of sulphide minerals produces a great variety of efflorescences of soluble sulphate salts. These minerals play an important role for environmental pollution, since they can be either a sink or a source for acidity and trace elements. This paper aims to characterise surface waters affected by mining activities in the Sierra Minera of Cartagena-La Union (SE, Spain). Water samples were analysed for trace metals (Zn, Cd, Pb, Cu, As and Fe), major ions (Na(+), K(+), Ca(2+) and Mg(2+)) and anions (F(-), Cl(-), NO3 (-), CO3 (2-), SO4 (2-)) concentrations and were submitted to an "evaporation-precipitation" experiment that consisted in identifying the salts resulting from the evaporation of the water aliquots sampled onsite. Mineralogy of the salts was studied using X-ray diffraction and compared with the results of calculations using VISUAL MINTEQ. The study area is heavily polluted as a result of historical mining and processing activities that has produced large amount of wastes characterised by a high trace elements content, acidic pH and containing minerals resulting from the supergene alteration of the raw materials. The mineralogical study of the efflorescences obtained from waters shows that magnesium, zinc, iron and aluminium sulphates predominate in the acid mine drainage precipitates. Minerals of the hexahydrite group have been quantified together with minerals of the rozenite group, alunogen and other phases such as coquimbite and copiapite. Calcium sulphates correspond exclusively to gypsum. In a semiarid climate, such as that of the study area, these minerals contribute to understand the response of the system to episodic rainfall events. MINTEQ model could be used for the analysis of waters affected by mining activities but simulation of evaporation gives more realistic results considering that MINTEQ does not consider soluble hydrated salts.

Determining trace gas flux from container-grown woody ornamentals

USDA-ARS?s Scientific Manuscript database

In recent years, anthropogenic climate change and its effects on the global environment has garnered significant attention from the scientific community. Increased trace gas emissions (CO2, CH4, and N2O) are widely believed to be the driving force behind global warming. Agriculture is a large contri...

ATMOSPHERIC DRY PARTICLE DEPOSITION OF POPS AND TRACE METALS IN AN URBAN- AND INDUSTRIALLY-IMPACTED MID-ATLANTIC ESTUARY (AEOLOS B MID-ATLANTIC)

EPA Science Inventory

Emissions of hazardous air pollutants into the coastal urban-industrial atmosphere increase atmospheric depositional fluxes to proximate water bodies. Dry deposition of large particles containing persistent organic pollutants (POPs) and trace metals were a major contribu...

RIP-REMOTE INTERACTIVE PARTICLE-TRACER

NASA Technical Reports Server (NTRS)

Rogers, S. E.

1994-01-01

Remote Interactive Particle-tracing (RIP) is a distributed-graphics program which computes particle traces for computational fluid dynamics (CFD) solution data sets. A particle trace is a line which shows the path a massless particle in a fluid will take; it is a visual image of where the fluid is going. The program is able to compute and display particle traces at a speed of about one trace per second because it runs on two machines concurrently. The data used by the program is contained in two files. The solution file contains data on density, momentum and energy quantities of a flow field at discrete points in three-dimensional space, while the grid file contains the physical coordinates of each of the discrete points. RIP requires two computers. A local graphics workstation interfaces with the user for program control and graphics manipulation, and a remote machine interfaces with the solution data set and performs time-intensive computations. The program utilizes two machines in a distributed mode for two reasons. First, the data to be used by the program is usually generated on the supercomputer. RIP avoids having to convert and transfer the data, eliminating any memory limitations of the local machine. Second, as computing the particle traces can be computationally expensive, RIP utilizes the power of the supercomputer for this task. Although the remote site code was developed on a CRAY, it is possible to port this to any supercomputer class machine with a UNIX-like operating system. Integration of a velocity field from a starting physical location produces the particle trace. The remote machine computes the particle traces using the particle-tracing subroutines from PLOT3D/AMES, a CFD post-processing graphics program available from COSMIC (ARC-12779). These routines use a second-order predictor-corrector method to integrate the velocity field. Then the remote program sends graphics tokens to the local machine via a remote-graphics library. The local machine interprets the graphics tokens and draws the particle traces. The program is menu driven. RIP is implemented on the silicon graphics IRIS 3000 (local workstation) with an IRIX operating system and on the CRAY2 (remote station) with a UNICOS 1.0 or 2.0 operating system. The IRIS 4D can be used in place of the IRIS 3000. The program is written in C (67%) and FORTRAN 77 (43%) and has an IRIS memory requirement of 4 MB. The remote and local stations must use the same user ID. PLOT3D/AMES unformatted data sets are required for the remote machine. The program was developed in 1988.

How Markovian is exciton dynamics in purple bacteria?

NASA Astrophysics Data System (ADS)

Vaughan, Felix; Linden, Noah; Manby, Frederick R.

2017-03-01

We investigate the extent to which the dynamics of excitons in the light-harvesting complex LH2 of purple bacteria can be described using a Markovian approximation. To analyse the degree of non-Markovianity in these systems, we introduce a measure based on fitting Lindblad dynamics, as well as employing a recently introduced trace-distance measure. We apply these measures to a chromophore-dimer model of exciton dynamics and use the hierarchical equation-of-motion method to take into account the broad, low-frequency phonon bath. With a smooth phonon bath, small amounts of non-Markovianity are present according to the trace-distance measure, but the dynamics is poorly described by a Lindblad master equation unless the excitonic dimer coupling strength is modified. Inclusion of underdamped, high-frequency modes leads to significant deviations from Markovian evolution in both measures. In particular, we find that modes that are nearly resonant with gaps in the excitonic spectrum produce dynamics that deviate most strongly from the Lindblad approximation, despite the trace distance measuring larger amounts of non-Markovianity for higher frequency modes. Overall we find that the detailed structure in the high-frequency region of the spectral density has a significant impact on the nature of the dynamics of excitons.

Quantitative Determining of Ultra-Trace Aluminum Ion in Environmental Samples by Liquid Phase Microextraction Assisted Anodic Stripping Voltammetry.

PubMed

Zhang, Liuyang; Luo, Jinju; Shen, Xinyu; Li, Chunya; Wang, Xian; Nie, Bei; Fang, Huaifang

2018-05-10

Direct detecting of trace amount Al(III) in aqueous solution by stripping voltammetry is often frustrated by its irreversible reduction, resided at −1.75 V (vs. Ag/AgCl reference), which is in a proximal potential of proton reduction. Here, we described an electroanalytical approach, combined with liquid phase microextraction (LPME) using ionic liquid (IL), to quantitatively assess trace amount aluminum in environmental samples. The Al(III) was caged by 8-hydroxyquinoline, forming a superb hydrophobic metal⁻chelate, which sequentially transfers and concentrates in the bottom layer of IL-phase during LPME. The preconcentrated Al(III) was further analyzed by a square-wave anodic stripping voltammetry (SW-ASV). The resulting Al-deposited electrodes were characterized by scanning electron microscopy and powder X-ray diffraction, showing the intriguing amorphous nanostructures. The method developed provides a linear calibration ranging from 0.1 to 1.2 ng L −1 with a correlation coefficient of 0.9978. The LOD attains as low as 1 pmol L −1 , which reaches the lowest report for Al(III) detection using electroanalytical techniques. The applicable methodology was implemented for monitoring Al(III) in commercial distilled water.

Foundations of a query and simulation system for the modeling of biochemical and biological processes.

PubMed

Antoniotti, M; Park, F; Policriti, A; Ugel, N; Mishra, B

2003-01-01

The analysis of large amounts of data, produced as (numerical) traces of in vivo, in vitro and in silico experiments, has become a central activity for many biologists and biochemists. Recent advances in the mathematical modeling and computation of biochemical systems have moreover increased the prominence of in silico experiments; such experiments typically involve the simulation of sets of Differential Algebraic Equations (DAE), e.g., Generalized Mass Action systems (GMA) and S-systems. In this paper we reason about the necessary theoretical and pragmatic foundations for a query and simulation system capable of analyzing large amounts of such trace data. To this end, we propose to combine in a novel way several well-known tools from numerical analysis (approximation theory), temporal logic and verification, and visualization. The result is a preliminary prototype system: simpathica/xssys. When dealing with simulation data simpathica/xssys exploits the special structure of the underlying DAE, and reduces the search space in an efficient way so as to facilitate any queries about the traces. The proposed system is designed to give the user possibility to systematically analyze and simultaneously query different possible timed evolutions of the modeled system.

Multielemental analysis in vegetable edible oils by inductively coupled plasma mass spectrometry after solubilisation with tetramethylammonium hydroxide.

PubMed

Savio, Marianela; Ortiz, María S; Almeida, César A; Olsina, Roberto A; Martinez, Luis D; Gil, Raúl A

2014-09-15

Trace metals have negative effects on the oxidative stability of edible oils and they are important because of possibility for oils characterisation. A single-step procedure for trace elemental analysis of edible oils is presented. To this aim, a solubilisation with tetramethylammonium hydroxide (TMAH) was assayed prior to inductively coupled plasma mass spectrometry detection. Small amounts of TMAH were used, resulting in high elemental concentrations. This method was applied to edible oils commercially available in Argentine. Elements present in small amounts (Cu, Ge, Mn, Mo, Ni, Sb, Sr, Ti, and V) were determined in olive, corn, almond and sunflower oils. The limits of detection were between 0.004 μg g(-1) for Mn and Sr, and 0.32 μg g(-1) for Sb. Principal components analysis was used to correlate the content of trace metals with the type of oils. The two first principal components retained 91.6% of the variability of the system. This is a relatively simple and safe procedure, and could be an attractive alternative for quality control, traceability and routine analysis of edible oils. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of Ground Patterns Size on FM-Band Cross-Talks between Two Parallel Signal Traces of Printed Circuit Boards for Vehicles

NASA Astrophysics Data System (ADS)

Iida, Michihira; Maeno, Tsuyoshi; Fujiwara, Osamu

It is well known that electromagnetic disturbances in vehicle-mounted radios are mainly caused by conducted noise currents flowing through wiring-harnesses from vehicle-mounted printed circuit boards (PCBs) with common ground patterns containing slits. To suppress the noise currents outflow from PCBs of these kinds, we previously measured noise currents outflow from simple two-layer PCBs having two parallel signal traces and different ground patterns with/without slits to reveal that making slits with open ends on the ground patterns in parallel with the traces can reduce the conducted noise currents. In the present study, with FDTD simulation, we investigated reduction effects of ground patterns size on the FM-band cross-talk noise levels between two parallel signal traces, by using four types of simple PCB models having different ground patterns formed in different numbers but containing the same planar dimension slits parallel to the traces, in addition to two types of PCB models with different ground patterns divided into two parts parallel to the traces. As a result, we found that the cross-talk noise currents for the above six types of PCBs decrease by 6.9-8.5dB compared to the PCB which has a plain ground with no slits. From this study, we got the finding that the contributing factor for the above mentioned cross-talk reduction relies on the reduction of mutual inductance between the two parallel traces. In addition, in case of this study, it is interesting to note that the noise currents outflow from PCBs can rather be suppressed when the size of the return ground of each signal trace is small.

Evaluation of a new electronic preoperative reference marker for toric intraocular lens implantation by two different methods of analysis: Adobe Photoshop versus iTrace.

PubMed

Farooqui, Javed Hussain; Sharma, Mansi; Koul, Archana; Dutta, Ranjan; Shroff, Noshir Minoo

2017-01-01

The aim of this study is to compare two different methods of analysis of preoperative reference marking for toric intraocular lens (IOL) after marking with an electronic marker. Cataract and IOL Implantation Service, Shroff Eye Centre, New Delhi, India. Fifty-two eyes of thirty patients planned for toric IOL implantation were included in the study. All patients had preoperative marking performed with an electronic preoperative two-step toric IOL reference marker (ASICO AE-2929). Reference marks were placed at 3-and 9-o'clock positions. Marks were analyzed with two systems. First, slit-lamp photographs taken and analyzed using Adobe Photoshop (version 7.0). Second, Tracey iTrace Visual Function Analyzer (version 5.1.1) was used for capturing corneal topograph examination and position of marks noted. Amount of alignment error was calculated. Mean absolute rotation error was 2.38 ± 1.78° by Photoshop and 2.87 ± 2.03° by iTrace which was not statistically significant ( P = 0.215). Nearly 72.7% of eyes by Photoshop and 61.4% by iTrace had rotation error ≤3° ( P = 0.359); and 90.9% of eyes by Photoshop and 81.8% by iTrace had rotation error ≤5° ( P = 0.344). No significant difference in absolute amount of rotation between eyes when analyzed by either method. Difference in reference mark positions when analyzed by two systems suggests the presence of varying cyclotorsion at different points of time. Both analysis methods showed an approximately 3° of alignment error, which could contribute to 10% loss of astigmatic correction of toric IOL. This can be further compounded by intra-operative marking errors and final placement of IOL in the bag.

Establishment and analysis of in vitro biomass from Salvia corrugata Vahl. and evaluation of antimicrobial activity.

PubMed

Bisio, Angela; Fraternale, Daniele; Schito, Anna Maria; Parricchi, Anita; Dal Piaz, Fabrizio; Ricci, Donata; Giacomini, Mauro; Ruffoni, Barbara; De Tommasi, Nunziatina

2016-02-01

Demethylfruticuline A and fruticuline A, the most abundant compounds from the surface extract of Salvia corrugata Vahl., have shown antibacterial, antitumor and cytotoxic activities. In order to obtain these icetexane diterpenes from in vitro cultures of S. corrugata, protocols were developed for callus production, micropropagation and shoot regeneration. Analysis of the regenerated shoots showed the presence of both icetexanes, micropropagated plants contained only fruticuline A, while the callus contained trace amounts of both diterpenes. The yield of fruticuline A was higher in the methanolic extract of regenerated shoots than in those of fresh leaves and fresh shoot tips. In addition to these diterpenes, the regenerated shoot and micropropagated plant extracts afforded seven other diterpenes, one icetexane and six abietanes, identified by UV, IR, 1D- and 2D-NMR and HR-MS analysis. Five compounds (19-acetoxy-7α-hydroxyroyleanone, 7β,20-epoxy-11,12,19-trihydroxyabieta-8,11,13-triene, 7,20-dihydrofruticuline A, 7β-acetoxy-20-hydroxy-19,20-epoxyroyleanone, 7β-ethoxy-6β,20:19,20-diepoxyroyleanone) were previously undescribed. Although the crude plant surface extract did not possess any antibacterial activity, methanolic extracts of in vitro tissues and two compounds, namely 7β-acetoxy-20-hydroxy-19,20-epoxyroyleanone and 7β-ethoxy-6β,20:19,20-diepoxyroyleanone, isolated in suitable amounts, were active in varying degrees against multidrug resistant clinical strains of Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis and Enterococcus faecium, displaying MIC values ranging from 32, 64 to 128μg/mL. Copyright © 2015 Elsevier Ltd. All rights reserved.

Solid phase extraction of trace amounts of cadmium(II) ions in water and food samples using iron magnetite nanoparticles modified by sodium dodecyl sulfate and 2-mercaptobenzothiazole.

PubMed

Abbasi, Shahriar; ShanbehDehbalai, Mehdi; Khani, Hossein

2017-03-01

A new, simple and rapid method for solid phase extraction and preconcentration of trace amounts of cadmium ions using 2-mercaptobenzothiazole/sodium dodecyl sulfate immobilized on magnetite nanoparticles (MBT-SDS-MNPs) was proposed. The method is based on the extraction of cadmium ions via complexation with MBT immobilized on SDS-coated MNPs and their determination by flame atomic absorption spectrometry. The effects of different parameters - pH; eluent type, concentration and volume; amounts of salt and adsorbent; contact time and interfering ions - on the adsorption of cadmium ions were studied. Under optimized conditions, the calibration curve was linear in the range of 10-5,000 μg L -1 . Detection limit and relative standard deviation of the proposed method were 0.009 μg L -1 and 2.2%, respectively. The adsorption data were analyzed by Langmuir and Freundlich isotherm models and a maximum adsorption amount of 24.80 mg g -1 , a Langmuir adsorption equilibrium constant (b) of 4.62 and Freundlich constants K f and n of 6.075 mg 1-1/n L 1/n g -1 and 2.391, respectively, were obtained. Finally, this adsorbent was successfully used for extraction of cadmium from water and food samples.

27 CFR 5.23 - Alteration of class and type.

Code of Federal Regulations, 2014 CFR

2014-04-01

... trace amount of citric acid. (b) Extractions. The removal from any distilled spirits of any constituents... than 15 percent of the fixed acids, or volatile acids, or esters, or soluble solids, or higher alcohols...

27 CFR 5.23 - Alteration of class and type.

Code of Federal Regulations, 2012 CFR

2012-04-01

... trace amount of citric acid. (b) Extractions. The removal from any distilled spirits of any constituents... than 15 percent of the fixed acids, or volatile acids, or esters, or soluble solids, or higher alcohols...

27 CFR 5.23 - Alteration of class and type.

Code of Federal Regulations, 2013 CFR

2013-04-01

... trace amount of citric acid. (b) Extractions. The removal from any distilled spirits of any constituents... than 15 percent of the fixed acids, or volatile acids, or esters, or soluble solids, or higher alcohols...

26 CFR 301.6362-5 - Qualified nonresident tax.

Code of Federal Regulations, 2010 CFR

2010-04-01

... which bears the same ratio to such sum as the amount described in subdivision (i) of this subparagraph... tracing of the profitability of each phase and aspect of the partnership's operations, and shows the State...

Biogeochemical and hydrological controls on fate and distribution of trace metals in oiled Gulf salt marshes

NASA Astrophysics Data System (ADS)

Keevan, J.; Natter, M.; Lee, M.; Keimowitz, A.; Okeke, B.; Savrda, C.; Saunders, J.

2011-12-01

On April 20, 2010, the drilling rig Deepwater Horizon exploded in the Gulf of Mexico, resulting in the release of approximately 5 million barrels of crude oil into the environment. Oil and its associated trace metals have been demonstrated to have a detrimental effect on coastal wetland ecosystems. Wetlands are particularly susceptible to oil contamination because they are composed largely of fine-grained sediments, which have a high capacity to adsorb organic matter and metals. The biogeochemical cycling of trace metals can be strongly influenced by microbial activity, specifically those of sulfate- and iron-reducing bacteria. Microbial activity may be enhanced by an increase in amounts of organic matter such as oil. This research incorporates an assessment of levels of trace metals and associated biogeochemical changes from ten coastal marshes in Alabama, Mississippi, and Louisiana. These sampling sites range in their pollution levels from pristine to highly contaminated. A total digestion analysis of wetland sediments shows higher concentrations of certain trace metals (e.g., Ni, Cu, Pb, Zn, Sr, Co, V, Ba, Hg, As) in heavily-oiled areas compared to less-affected and pristine sites. Due to chemical complexation among organic compounds and metals, crude oils often contain elevated levels (up to hundreds of mg/kg) of trace metals At the heavily-oiled Louisiana sites (e.g., Bay Jimmy, Bayou Dulac, Bay Batiste), elevated levels of metals and total organic carbon have been found in sediments down to depths of 30 cm. Clearly the contamination is not limited to shallow sediments and oil, along with various associated metals, may be invading into deeper (pre-industrial) portions of the marsh sediments. Pore-waters extracted from contaminated sediments are characterized by very high levels of reduced sulfur (up to 80 mg/kg), in contrast to fairly low ferrous iron concentrations (<0.02 mg/kg). The influx of oil into the wetlands might provide the initial substrate and carbon source for stimulating sulfate-reducing bacteria. The high sulfur levels, coupled with the low levels of iron, indicate that iron-reducing bacteria are outcompeted by sulfate reducers in oiled salt marshes. Moreover, pore-water pH values show a general increasing trend (ranging from 6.6 to 8.0) with depth, possibly reflecting the combined effects of bacterial sulfate reduction and saltwater intrusion at depth. Despite high levels of trace metals in bulk sediments, concentrations of trace metals dissolved in pore-waters are generally low. It is very likely that high organic matter content and bacterially-mediated sulfate reduction promote metal retention through the formation of sulfide solids. Framboidal pyrites, as well as other sulfides, have been identified, and are currently undergoing XRD, SEM, and EDAX analyses. Continued research is needed to monitor possible re-mobilization of trace metals in changing redox and biogeochemical conditions.

Preparation and provisional certification of NBL Spectrographic Impurity Standards, CRM 123 (1-7) and 124 (1-7)

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

Santoliquido, P.M.

This report describes the design, production, and provisional certification of two new certified reference materials (CRMs): CRM No. 123 (1-7), U/sub 3/O/sub 8/ containing 18 trace elements, and CRM No. 124 (1-7), U/sub 3/O/sub 8/ containing 24 trace elements. The elements to be included and concentrations to be used were decided on the basis of information gathered from users of a previous CRM of this type, CRM No. 98 (1-7). The new CRMs were prepared by the addition of trace elements to high purity U/sub 3/O/sub 8/. Provisional certification was accomplished by an interlaboratory program in which four different laboratoriesmore » analyzed the materials by carrier distillation dc arc emission spectrography.« less

Determination of the δ2H and δ18O of soil water and water in plant matter; RSIL lab code 1700

USGS Publications Warehouse

Revesz, Kinga M.; Buck, Bryan; Coplen, Tyler B.

2012-01-01

The purpose of the Reston Stable Isotope Laboratory lab code 1700 is to determine the δ2H/1H), abbreviated as δ2H, and the δ18O/16O), abbreviated as δ18O, of soil water and water in plant matter. This method is based on the observation that water and toluene form an azeotropic mixture at 84.1 °C. This temperature is substantially lower than the boiling points of water (100 °C) and toluene (110 °C), but water and toluene are immiscible at ambient temperature. The water content of a soil or plant is determined by weighing, drying, and reweighing a small amount of sample. Sufficient sample to collect 3 to 5 milliliters of water after distillation is loaded into a distillation flask. Sufficient toluene is added so that the sample is immersed throughout the entire distillation to minimize evaporation of water, which would affect the δ2H and δ18O values. The mixture of sample and toluene is heated in a flask to its boiling point (84.1 °C) so that water from the sample and toluene can distill together into a specially designed collection funnel. The temperature of 84.1 °C is maintained until the water has been quantitatively transferred to the collection funnel, at which time the temperature is raised to the boiling point of the remaining component (toluene, 110 °C). The collection funnel is maintained at ambient temperature so that the sample water and toluene can be separated physically. After separation, the sample water is purified by addition of paraffin wax to the container with the sample water, capping the container, and heating to approximately 60 °C to melt the wax. Trace amounts of toluene will dissolve in the wax, purifying the sample water for isotopic analysis. The isotopic composition of the purified water is then determined by equilibration with gaseous hydrogen or carbon dioxide, followed by dual-inlet isotope-ratio mass spectrometry. Because laser-absorption spectrometry is sensitive to organic compounds, such as trace toluene remaining in water samples, water samples should be analyzed for isotopic composition only by mass spectrometry and not by laser-absorption spectrometry.

Logistics of community smallpox control through contact tracing and ring vaccination: a stochastic network model.

PubMed

Porco, Travis C; Holbrook, Karen A; Fernyak, Susan E; Portnoy, Diane L; Reiter, Randy; Aragón, Tomás J

2004-08-06

Previous smallpox ring vaccination models based on contact tracing over a network suggest that ring vaccination would be effective, but have not explicitly included response logistics and limited numbers of vaccinators. We developed a continuous-time stochastic simulation of smallpox transmission, including network structure, post-exposure vaccination, vaccination of contacts of contacts, limited response capacity, heterogeneity in symptoms and infectiousness, vaccination prior to the discontinuation of routine vaccination, more rapid diagnosis due to public awareness, surveillance of asymptomatic contacts, and isolation of cases. We found that even in cases of very rapidly spreading smallpox, ring vaccination (when coupled with surveillance) is sufficient in most cases to eliminate smallpox quickly, assuming that 95% of household contacts are traced, 80% of workplace or social contacts are traced, and no casual contacts are traced, and that in most cases the ability to trace 1-5 individuals per day per index case is sufficient. If smallpox is assumed to be transmitted very quickly to contacts, it may at times escape containment by ring vaccination, but could be controlled in these circumstances by mass vaccination. Small introductions of smallpox are likely to be easily contained by ring vaccination, provided contact tracing is feasible. Uncertainties in the nature of bioterrorist smallpox (infectiousness, vaccine efficacy) support continued planning for ring vaccination as well as mass vaccination. If initiated, ring vaccination should be conducted without delays in vaccination, should include contacts of contacts (whenever there is sufficient capacity) and should be accompanied by increased public awareness and surveillance.

Effective Trapping of Fruit Flies with Cultures of Metabolically Modified Acetic Acid Bacteria

PubMed Central

Ishii, Yuri; Akasaka, Naoki; Goda, Itsuko; Sakoda, Hisao

2015-01-01

Acetoin in vinegar is an attractant to fruit flies when combined with acetic acid. To make vinegar more effective in attracting fruit flies with increased acetoin production, Komagataeibacter europaeus KGMA0119 was modified by specific gene disruption of the acetohydroxyacid isomeroreductase gene (ilvC). A previously constructed mutant lacking the putative ligand-sensing region in the leucine-responsive regulatory protein (KeLrp, encoded by Kelrp) was also used. The ilvC and Kelrp disruptants (KGMA5511 and KGMA7203, respectively) produced greater amounts of acetoin (KGMA5511, 0.11%; KGMA7203, 0.13%) than the wild-type strain KGMA0119 (0.069%). KGMA7203 produced a trace amount of isobutyric acid (0.007%), but the other strains did not. These strains produced approximately equal amounts of acetic acid (0.7%). The efficiency of fruit fly attraction was investigated with cultured Drosophila melanogaster. D. melanogaster flies (approximately 1,500) were released inside a cage (2.5 m by 2.5 m by 1.5 m) and were trapped with a device containing vinegar and a sticky sheet. The flies trapped on the sticky sheet were counted. The cell-free supernatant from KGMA7203 culture captured significantly more flies (19.36 to 36.96% of released flies) than did KGMA0119 (3.25 to 11.40%) and KGMA5511 (6.87 to 21.50%) cultures. Contrastingly, a 0.7% acetic acid solution containing acetoin (0.13%) and isobutyric acid (0.007%), which mimicked the KGMA7203 supernatant, captured significantly fewer flies (0.88 to 4.57%). Furthermore, the KGMA0119 supernatant with additional acetoin (0.13%) and isobutyric acid (0.007%) captured slightly more flies than the original KGMA0119 supernatant but fewer than the KGMA7203 supernatant, suggesting that the synergistic effects of acetic acid, acetoin, isobutyric acid, and unidentified metabolites achieved the efficient fly trapping of the KGMA7203 supernatant. PMID:25595769

Developmental control of apiogalacturonan biosynthesis and UDP-apiose production in a duckweed. [Spirodela polyrrhiza

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

Longland, J.M.; Fry, S.C.; Trewavas, A.J.

1989-07-01

Vegetative fronds of Spirodela polyrrhiza were induced to form dormant turions by the addition of 1 micromolar abscisic acid or by shading. The cell wall polymers of fronds contained a high proportion of the branched-chain pentose, D-apiose (about 20% of total noncellulosic wall sugar residues), whereas turion cell walls contained only trace amounts (about 0.2%). When the fronds were fed D-({sup 3}H)glucuronic acid for 30 minutes, the accumulated UDP-({sup 3}H)apiose pool accounted for about 27% of the total phosphorylated ({sup 3}H)pentose derivatives; in turions, the UDP({sup 3}H)apiose pool accounted for only about 4% of the total phosphorylated ({sup 3}H)pentose derivatives.more » They conclude that the developmentally regulated decrease in the biosynthesis of a wall polysaccharide during turion formation involves a reduction in the supply of the relevant sugar nucleotide. One controlling enzyme activity is suggested to be UDP-apiose/UDP-xylose synthase. However, since there was a 100-fold decrease in the rate of polysaccharide synthesis and only a 9-fold decrease in UDP-apiose accumulation, there is probably also control of the activity of the relevant polysaccharide synthase.« less

Geochemistry of autochthonous and hypautochthonous siderite-dolomite coal-balls (Foord Seam, Bolsovian, Upper Carboniferous), Nova Scotia, Canada

USGS Publications Warehouse

Zodrow, E.L.; Lyons, P.C.; Millay, M.A.

1996-01-01

The 11-13 m thick Foord Seam in the fault-bounded Stellarton Basin, Nova Scotia, is the thickest seam from the Euramerican floral province known to contain coal-balls. In addition to the first discovery of autochthonous coal-balls in the Foord Seam, Nova Scotia, its shale parting also contains hypautochthonous coal-balls with histologically preserved plant structures. The coal-ball discovery helps fill a stratigraphic gap in coal-ball occurrences in the upper Carboniferous (Bolsovian) of Euramerica. The autochthonous and hypautochthonous coal-balls have a similar mineralogical composition and are composed of siderite (81-100%), dolomite-ankerite (0-19%), minor quartz and illite, and trace amounts of 'calcite'. Similar is also their permineralizing mineralogy, which consists of dolomite-ankerite and siderite. Their low pyrite content and carbonate mineralogy, and nonmarine origin, differentiates the Foord Seam coal-balls from other Euramerican coal-ball occurrences. A preliminary geochemical model, which is based on oxygen and carbon isotopic data, indicates that siderite in both the autochthonous and hypautochthonous coal-balls is of very early diagenetic (nonmarine) origin from 13C-enriched bicarbonate derived from bacterial methanogenesis of organic matter.

Modulation of endothelial GSH concentrations: effect of exogenous GSH and GSH monoethyl ester

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

Tsan, M.F.; White, J.E.; Rosano, C.L.

We studied the effects of exogenous glutathione (GSH) and GSH monoethyl ester (GSH-MEE) on the enhancement of endothelial GSH concentrations. The preparation of GSH-MEE used contained 91% GSH-MEE, approximately 9% GSH diethyl ester (GSH-DEE) and a trace amount of GSH. Both GSH and GSH-MEE markedly stimulated the intracellular concentrations of GSH in endothelial cells. GSH-MEE was more potent than GSH. The enhancement of endothelial GSH concentration by exogenous GSH was completely inhibited by buthionine sulfoximine (BSO), a potent inhibitor of gamma-glutamylcysteine synthase, or acivicin (AT-125), an inhibitor of gamma-glutamyl transpeptidase, suggesting that it was due to the extracellular breakdown andmore » subsequent intracellular resynthesis of GSH. In contrast, the effect of GSH-MEE was largely resistant to BSO and acivicin, suggesting that it was primarily due to transport of GSH-MEE followed by intracellular hydrolysis. The GSH-MEE preparation, which contained 9% GSH-DEE, at concentrations of 2 mM or higher caused vacuolization of endothelial cells. The enhancement of GSH concentrations by exogenous GSH, but not by GSH-MEE, protected endothelial cells against H/sub 2/O/sub 2/-induced injury.« less

Preconcentration determination of arsenic species by sorption of As(V) on Amberlite IRA-410 coupled with fluorescence quenching of L-cysteine capped CdS nanoparticles.

PubMed

Hosseini, Mohammad Saeid; Nazemi, Sahar

2013-10-07

A simple and accurate method for arsenic speciation analysis in natural and drinking water samples is described in which preconcentration of arsenic as As(V) was coupled with spectrofluorometric determination. The extracted As(V) species with a column containing Amberlite IRA-410 were subjected to L-cysteine capped CdS quantum dots (QDs) and the fluorescence quenching of the QDs due to reduction of As(V) by L-cysteine was considered as a signal relevant to As(V) concentration. The As(III) species were also determined after oxidation of As(III) ions to As(V) with H2O2 and measurement of the total arsenic content. In treatment with 400 mL portions of water samples containing 30 μg L(-1) As(V), the relative standard deviation was 2.8%. The detection limit of arsenic was also found to be 0.75 μg L(-1) (1 × 10(-8) M). The reliability of proposed method was confirmed using certified reference materials. The trace amounts of arsenic species were then determined in different water samples, satisfactorily.

Fine-Grained Rims in the Allan Hills 81002 and Lewis Cliff 90500 CM2 Meteorites: Their Origin and Modification

NASA Technical Reports Server (NTRS)

Hua, X.; Wang, J.; Buseck, P. R.

2002-01-01

Antarctic CM meteorites Allan Hills (ALH) 8 1002 and Lewis Cliff (LEW) 90500 contain abundant fine-grained rims (FGRs) that surround a variety of coarse-grained objects. FGRs from both meteorites have similar compositions and petrographic features, independent of their enclosed objects. The FGRs are chemically homogeneous at the 10 m scale for major and minor elements and at the 25 m scale for trace elements. They display accretionary features and contain large amounts of volatiles, presumably water. They are depleted in Ca, Mn, and S but enriched in P. All FGRs show a slightly fractionated rare earth element (REE) pattern, with enrichments of Gd and Yb and depletion of Er. Gd is twice as abundant as Er. Our results indicate that those FGRs are not genetically related to their enclosed cores. They were sampled from a reservoir of homogeneously mixed dust, prior to accretion to their parent body. The rim materials subsequently experienced aqueous alteration under identical conditions. Based on their mineral, textural, and especially chemical similarities, we conclude that ALH 8 1002 and LEW 90500 likely have a similar or identical source.

The origin of the argonium emission discovered in the Crab Nebula

NASA Astrophysics Data System (ADS)

Priestley, Felix; Barlow, Mike; Viti, Serena

2016-06-01

We present a study of the origin of the argonium (ArH+) emission discovered by Herschel in the Crab Nebula (Barlow et al. 2013). The argonium molecule is believed to be formed principally by the reaction of singly ionised argon (Ar+) with molecular hydrogen (H2), and to be destroyed by reactions with H2 and UV photons. For the case of the argonium ground state absorption lines seen by Herschel along several interstellar sightlines (Schilke et al. 2014), those authors argued that the presence of H2 in both the formation and destruction mechanisms means that ArH+ must form in largely atomic interstellar hydrogen clouds containing only trace amounts of H2. However, In the case of the Crab Nebula the observed argonium emission might originate either from transition regions containing both Ar+ and H2, or alternatively from inside the Crab Nebula's H2 knots into which X-ray photons or charged particles from the pulsar wind nebula have penetrated to produce Ar+ and other ions. We report the results of our numerical studies that have used a combination of photoionisation and photodissociation region codes to investigate these alternative scenarios for producing ArH+ in the Crab Nebula.

Effect of electric arc furnace slag on growth and physiology of maize (Zea mays L.).

PubMed

Radić, Sandra; Crnojević, Helena; Sandev, Dubravka; Jelić, Sonja; Sedlar, Zorana; Glavaš, Katarina; Pevalek-Kozlina, Branka

2013-12-01

Basic slag, used in this study as a potential source of certain nutrients, is a byproduct of the production of steel in electric arc furnace (EAF). A pot experiment with two nutrient-poor substrates was conducted to investigate to compare the effect of EAF steel slag and fertilizers NPK + F e on growth and availability of specific nutrients to maize. Mineral content of both substrate and plant leaves, growth, chlorophyll fluorescence and photosynthetic pigments were measured following six weeks of cultivation. As steel slag also contains trace amounts of heavy metals, certain oxidative parameters (antioxidative enzyme activities and lipid peroxidation) were evaluated as well. The steel slag improved soil mineral composition, increased above ground maize biomass by providing Fe, Mn, Mg, K and partly P and improved photosynthetic parameters. The potential phytotoxicity of EAF slag containing substrates was not determined as evaluated by MDA (malondialdehyde), GR (glutathione reductase) and APX (ascorbate peroxidase) levels. The obtained results show that EAF steel slag is comparable to NPK + F e in supplying nutrients for maize growth, indicating the potential of EAF steel slag as an inexpensive and non-phytotoxic nutrient supplier especially in poor soils.

Simultaneous visualization of the subfemtomolar expression of microRNA and microRNA target gene using HILO microscopy† †Electronic supplementary information (ESI) available: The LED device for the sample photobleaching, a schematic presentation of HILO microscopy, fluorescence spectra and hybridization curves of the molecular beacons, the linear correlation between the miRNA fluorescence intensity and the miRNA copy number, a validation of the miRNA adsorption and miRNA target gene expression via RT-qPCR, a validation of RT-qPCR using capillary electrophoresis, the reproducibility of RT-qPCR and Poisson distribution of the miRNA pipetting as well as a complete list of the oligonucleotides used in this study. See DOI: 10.1039/c7sc02701j Click here for additional data file.

PubMed Central

Lin, Yi-Zhen; Ou, Da-Liang; Chang, Hsin-Yuan; Lin, Wei-Yu; Hsu, Chiun

2017-01-01

The family of microRNAs (miRNAs) not only plays an important role in gene regulation but is also useful for the diagnosis of diseases. A reliable method with high sensitivity may allow researchers to detect slight fluctuations in ultra-trace amounts of miRNA. In this study, we propose a sensitive imaging method for the direct probing of miR-10b (miR-10b-3p, also called miR-10b*) and its target (HOXD10 mRNA) in fixed cells based on the specific recognition of molecular beacons combined with highly inclined and laminated optical sheet (HILO) fluorescence microscopy. The designed dye-quencher-labelled molecular beacons offer excellent efficiencies of fluorescence resonance energy transfer that allow us to detect miRNA and the target mRNA simultaneously in hepatocellular carcinoma cells using HILO fluorescence microscopy. Not only can the basal trace amount of miRNA be observed in each individual cell, but the obtained images also indicate that this method is useful for monitoring the fluctuations in ultra-trace amounts of miRNA when the cells are transfected with a miRNA precursor or a miRNA inhibitor (anti-miR). Furthermore, a reasonable causal relation between the miR-10b and HOXD10 expression levels was observed in miR-10b* precursor-transfected cells and miR-10b* inhibitor-transfected cells. The trends of the miRNA alterations obtained using HILO microscopy completely matched the RT-qPCR data and showed remarkable reproducibility (the coefficient of variation [CV] = 0.86%) and sensitivity (<1.0 fM). This proposed imaging method appears to be useful for the simultaneous visualisation of ultra-trace amounts of miRNA and target mRNA and excludes the procedures for RNA extraction and amplification. Therefore, the visualisation of miRNA and the target mRNA should facilitate the exploration of the functions of ultra-trace amounts of miRNA in fixed cells in biological studies and may serve as a powerful tool for diagnoses based on circulating cancer cells. PMID:28989695

Trace analysis of energetic materials via direct analyte-probed nanoextraction coupled to direct analysis in real time mass spectrometry.

PubMed

Clemons, Kristina; Dake, Jeffrey; Sisco, Edward; Verbeck, Guido F

2013-09-10

Direct analysis in real time mass spectrometry (DART-MS) has proven to be a useful forensic tool for the trace analysis of energetic materials. While other techniques for detecting trace amounts of explosives involve extraction, derivatization, solvent exchange, or sample clean-up, DART-MS requires none of these. Typical DART-MS analyses directly from a solid sample or from a swab have been quite successful; however, these methods may not always be an optimal sampling technique in a forensic setting. For example, if the sample were only located in an area which included a latent fingerprint of interest, direct DART-MS analysis or the use of a swab would almost certainly destroy the print. To avoid ruining such potentially invaluable evidence, another method has been developed which will leave the fingerprint virtually untouched. Direct analyte-probed nanoextraction coupled to nanospray ionization-mass spectrometry (DAPNe-NSI-MS) has demonstrated excellent sensitivity and repeatability in forensic analyses of trace amounts of illicit drugs from various types of surfaces. This technique employs a nanomanipulator in conjunction with bright-field microscopy to extract single particles from a surface of interest and has provided a limit of detection of 300 attograms for caffeine. Combining DAPNe with DART-MS provides another level of flexibility in forensic analysis, and has proven to be a sufficient detection method for trinitrotoluene (TNT), RDX, and 1-methylaminoanthraquinone (MAAQ). Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Removal of trace organic chemical contaminants by a membrane bioreactor.

PubMed

Trinh, T; van den Akker, B; Stuetz, R M; Coleman, H M; Le-Clech, P; Khan, S J

2012-01-01

Emerging wastewater treatment processes such as membrane bioreactors (MBRs) have attracted a significant amount of interest internationally due to their ability to produce high quality effluent suitable for water recycling. It is therefore important that their efficiency in removing hazardous trace organic contaminants be assessed. Accordingly, this study investigated the removal of trace organic chemical contaminants through a full-scale, package MBR in New South Wales, Australia. This study was unique in the context of MBR research because it characterised the removal of 48 trace organic chemical contaminants, which included steroidal hormones, xenoestrogens, pesticides, caffeine, pharmaceuticals and personal care products (PPCPs). Results showed that the removal of most trace organic chemical contaminants through the MBR was high (above 90%). However, amitriptyline, carbamazepine, diazepam, diclofenac, fluoxetine, gemfibrozil, omeprazole, sulphamethoxazole and trimethoprim were only partially removed through the MBR with the removal efficiencies of 24-68%. These are potential indicators for assessing MBR performance as these chemicals are usually sensitive to changes in the treatment systems. The trace organic chemical contaminants detected in the MBR permeate were 1 to 6 orders of magnitude lower than guideline values reported in the Australian Guidelines for Water Recycling. The outcomes of this study enhanced our understanding of the levels and removal of trace organic contaminants by MBRs.

Study of water-oil emulsion combustion in large pilot power plants for fine particle matter emission reduction

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

Allouis, C.; Beretta, F.; L'Insalata, A.

2007-04-15

The combustion of heavy fuel oil for power generation is a great source of carbonaceous and inorganic particle emissions, even though the combustion technologies and their efficiency are improving. The information about the size distribution function of the particles originated by trace metals present into the fuels is not adequate. In this paper, we focused our attention the influence of emulsion oil-water on the larger distribution mode of both the carbonaceous and metallic particles. Isokinetic sampling was performed at the exhausts of flames of a low-sulphur content heavy oil and its emulsion with water produced in two large pilot plants.more » The samples were size-segregated by mean of an 8-stages Andersen impactor. Further investigation performed on the samples using electronic microscopy (SEM) coupled with X-ray analysis (EDX) evidenced the presence of solid spherical particles, plerosphere, with typical dimensions ranging between 200 nm and 2-3 {mu}m, whose atomic composition contains a large amount of the trace metals present in the parent oils (Fe, V, Ni, etc.). EDX analyses revealed that the metal concentration increases as the plerosphere dimension decreases. We also observed that the use of emulsion slightly reduce the emission of fine particles (D{sub 50} < 8 {mu}m) in the large scale plant. (author)« less

The relation between amyotrophic lateral sclerosis and inorganic selenium in drinking water: a population-based case-control study

PubMed Central

2010-01-01

Background A community in northern Italy was previously reported to have an excess incidence of amyotrophic lateral sclerosis among residents exposed to high levels of inorganic selenium in their drinking water. Methods To assess the extent to which such association persisted in the decade following its initial observation, we conducted a population-based case-control study encompassing forty-one newly-diagnosed cases of amyotrophic lateral sclerosis and eighty-two age- and sex-matched controls. We measured long-term intake of inorganic selenium along with other potentially neurotoxic trace elements. Results We found that consumption of drinking water containing ≥ 1 μg/l of inorganic selenium was associated with a relative risk for amyotrophic lateral sclerosis of 5.4 (95% confidence interval 1.1-26) after adjustment for confounding factors. Greater amounts of cumulative inorganic selenium intake were associated with progressively increasing effects, with a relative risk of 2.1 (95% confidence interval 0.5-9.1) for intermediate levels of cumulative intake and 6.4 (95% confidence interval 1.3-31) for high intake. Conclusion Based on these results, coupled with other epidemiologic data and with findings from animal studies that show specific toxicity of the trace element on motor neurons, we hypothesize that dietary intake of inorganic selenium through drinking water increases the risk for amyotrophic lateral sclerosis. PMID:21134276

Quantifying Trace Amounts of Aggregates in Biopharmaceuticals Using Analytical Ultracentrifugation Sedimentation Velocity: Bayesian Analyses and F Statistics.

PubMed

Wafer, Lucas; Kloczewiak, Marek; Luo, Yin

2016-07-01

Analytical ultracentrifugation-sedimentation velocity (AUC-SV) is often used to quantify high molar mass species (HMMS) present in biopharmaceuticals. Although these species are often present in trace quantities, they have received significant attention due to their potential immunogenicity. Commonly, AUC-SV data is analyzed as a diffusion-corrected, sedimentation coefficient distribution, or c(s), using SEDFIT to numerically solve Lamm-type equations. SEDFIT also utilizes maximum entropy or Tikhonov-Phillips regularization to further allow the user to determine relevant sample information, including the number of species present, their sedimentation coefficients, and their relative abundance. However, this methodology has several, often unstated, limitations, which may impact the final analysis of protein therapeutics. These include regularization-specific effects, artificial "ripple peaks," and spurious shifts in the sedimentation coefficients. In this investigation, we experimentally verified that an explicit Bayesian approach, as implemented in SEDFIT, can largely correct for these effects. Clear guidelines on how to implement this technique and interpret the resulting data, especially for samples containing micro-heterogeneity (e.g., differential glycosylation), are also provided. In addition, we demonstrated how the Bayesian approach can be combined with F statistics to draw more accurate conclusions and rigorously exclude artifactual peaks. Numerous examples with an antibody and an antibody-drug conjugate were used to illustrate the strengths and drawbacks of each technique.

Geochemistry of a marine phosphate deposit: A signpost to phosphogenesis

USGS Publications Warehouse

Piper, David Z.; Perkins, R.B.

2014-01-01

The Permian age Phosphoria Formation in southeastern Idaho and adjoining states represents possibly the largest marine phosphate deposit in the world. The Meade Peak Member, which contains the highest concentrations and amount of carbonate fluorapatite in the formation, was not significantly altered by mechanical reworking during deposition or subsequently by chemical weathering. Thus, its present composition reflects properties of the Phosphoria Sea that were critical to its accumulation and possibly to the accumulation of most major marine phosphate deposits. These properties included the chemistry of the water column, the hydrography, and the level of primary productivity. Calculated accumulation rates of the PO43− and trace nutrients – Cd, Cu, Ni, and Zn – recorded a dynamic upwelling rate of c.30 m year−1 that supported primary productivity of 2g C m−2day−1. High accumulation rates of the hydrogenous redox-sensitive trace metals – Cr, Mo, U, and V – reflect bottom-water redox conditions that were dominantly suboxic, maintained by a balance between the oxidation of ~ 8% of the organic detritus that settled out of the photic zone and advection of bottom water with a residence time of c.10 years. A limited flux into the basin of siliciclastic lithogenous debris contributed further to elevated concentrations of the seawater-derived sediment fractions.

Volatilization and precipitation of tellurium by aerobic, tellurite-resistant marine microbes.

PubMed

Ollivier, Patrick R L; Bahrou, Andrew S; Marcus, Sarah; Cox, Talisha; Church, Thomas M; Hanson, Thomas E

2008-12-01

Microbial resistance to tellurite, an oxyanion of tellurium, is widespread in the biosphere, but the geochemical significance of this trait is poorly understood. As some tellurite resistance markers appear to mediate the formation of volatile tellurides, the potential contribution of tellurite-resistant microbial strains to trace element volatilization in salt marsh sediments was evaluated. Microbial strains were isolated aerobically on the basis of tellurite resistance and subsequently examined for their capacity to volatilize tellurium in pure cultures. The tellurite-resistant strains recovered were either yeasts related to marine isolates of Rhodotorula spp. or gram-positive bacteria related to marine strains within the family Bacillaceae based on rRNA gene sequence comparisons. Most strains produced volatile tellurides, primarily dimethyltelluride, though there was a wide range of the types and amounts of species produced. For example, the Rhodotorula spp. produced the greatest quantities and highest diversity of volatile tellurium compounds. All strains also produced methylated sulfur compounds, primarily dimethyldisulfide. Intracellular tellurium precipitates were a major product of tellurite metabolism in all strains tested, with nearly complete recovery of the tellurite initially provided to cultures as a precipitate. Different strains appeared to produce different shapes and sizes of tellurium containing nanostructures. These studies suggest that aerobic marine yeast and Bacillus spp. may play a greater role in trace element biogeochemistry than has been previously assumed, though additional work is needed to further define and quantify their specific contributions.

Identification of a new degradation product of the antifouling agent Irgarol 1051 in natural samples

USGS Publications Warehouse

Ferrer, I.; Barcelo, D.

2001-01-01

A main degradation product of Irgarol [2-(methylthio)-4-(tert-butylamino)-6-(cyclopropylamino)-s-triazine], one of the most widely used compounds in antifouling paints, was detected at trace levels in seawater and sediment samples collected from several marinas on the Mediterranean coast. This degradation product was identified as 2-methylthio-4-tert-butylamino-s-triazine. The unequivocal identification of this compound in seawater samples was carried out by solid-phase extraction (SPE) coupled on-line with liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry (LC-APCI-MS). SPE was carried out by passing 150 ml of seawater sample through a cartridge containing a polymeric phase (PLRP-s), with recoveries ranging from 92 to 108% (n=5). Using LC-MS detection in positive ion mode, useful structural information was obtained by increasing the fragmentor voltage, thus permitting the unequivocal identification of this compound in natural samples. Method detection limits were in the range of 0.002 to 0.005 ??g/l. Overall, the combination of on-line SPE and LC-APCI-MS represents an important advance in environmental analysis of herbicide degradation products in seawater, since it demonstrates that trace amounts of new polar metabolites may be determined rapidly. This paper reports the LC-MS identification of the main degradation product of Irgarol in seawater and sediment samples. ?? 2001 Elsevier Science B.V. All rights reserved.

Analysis of metallic traces from the biodegradation of endomedullary AZ31 alloy temporary implants in rat organs after long implantation times.

PubMed

Bodelón, O G; Iglesias, C; Garrido, J; Clemente, C; Garcia-Alonso, M C; Escudero, M L

2015-08-04

AZ31 alloy has been tested as a biodegradable material in the form of endomedullary implants in female Wistar rat femurs. In order to evaluate the accumulation of potentially toxic elements from the biodegradation of the implant, magnesium (Mg), aluminium (Al), zinc (Zn), manganese (Mn) and fluorine (F) levels have been measured in different organs such as kidneys, liver, lungs, spleen and brain. Several factors that may influence accumulation have been taken into account: how long the implant has been in place, whether or not the bone is fractured, and the presence of an MgF2 protective coating on the implant. The main conclusions and the clinical relevance of the study have been that AZ31 endomedullary implants have a degradation rate of about 60% after 13 months, which is fully compatible with fracture consolidation. Neither bone fracture nor an MgF2 coating seems to influence the accumulation of trace elements in the studied organs. Aluminium is the only alloying element in this study that requires special attention. The increase in Al recovered from the sampled organs represents 3.95% of the amount contained in the AZ31 implant. Al accumulates in a statistically significant way in all the organs except the brain. All of this suggests that in long-term tests AZ31 may be a suitable material for osteosynthesis.

Fermentation of food and feed: A technology for efficient utilization of macro and trace elements in monogastrics.

PubMed

Humer, Elke; Schedle, Karl

2016-09-01

Mineral deficiencies, especially of iron, zinc, and calcium, respectively, negatively affect human health and may lead to conditions such as iron deficiency anemia, rickets, osteoporosis, and diseases of the immune system. Cereal grains and legumes are of global importance in nutrition of monogastrics (humans and the respective domestic animals) and provide high amounts of several minerals, e.g., iron, zinc, and calcium. Nevertheless, their bioavailability is low. Plants contain phytates, the salts of phytic acid, chemically known as inositol-hexakisphosphate, which interact with several minerals and proteins. However, phytate may be hydrolysed by phytase. This enzyme is naturally present in plants and also widely distributed in microorganisms. Several food processing methods have been reported to enhance phytate hydrolysis, due to the activation of endogenous phytase activity or via the enzyme produced by microbes. In recent years, fermentation for food and feed improvement and preservation, respectively, has gained increasing interest as a promising method to degrade phytate and enhance mineral utilization in monogastrics. Indeed, several in vitro as well as in vivo studies confirm a positive effect on the utilization of minerals, such as P, Ca, Fe and Zn, using sourdough fermentation for baking or fermentation of legumes, mainly soybeans. This review summarizes the current knowledge regarding the potential of fermentation to enhance macro and trace element bioavailability in monogastric species. Copyright © 2016 Elsevier GmbH. All rights reserved.

Determining trace gas efflux from container production of woody nursery crops

USDA-ARS?s Scientific Manuscript database

In recent years, climate change and its effects on the global environment has garnered significant attention from the scientific community. Increased trace gas emissions of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) are widely believed to be the driving force behind global warming. ...

Spinel from Apollo 12 Olivine Mare Basalts: Chemical Systematics of Selected Major, Minor, and Trace Elements

NASA Technical Reports Server (NTRS)

Papike, J. J.; Karner, J. M.; Shearer, C. K.; Spilde, M. N.

2002-01-01

Spinels from Apollo 12 Olivine basalts have been studied by Electron and Ion microprobe techniques. The zoning trends of major, minor and trace elements provide new insights into the conditions under which planetary basalts form. Additional information is contained in the original extended abstract.

Reactor for removing ammonia

DOEpatents

Luo, Weifang [Livermore, CA; Stewart, Kenneth D [Valley Springs, CA

2009-11-17

Disclosed is a device for removing trace amounts of ammonia from a stream of gas, particularly hydrogen gas, prepared by a reformation apparatus. The apparatus is used to prevent PEM "poisoning" in a fuel cell receiving the incoming hydrogen stream.

Dangerous Elements.

ERIC Educational Resources Information Center

Pinkham, Jim

1994-01-01

Discusses legislation currently under consideration that sets standards for the amount of radon, aluminum, and arsenic allowable in drinking water. Considers the economic impact of the legislation and traces the status of the Safe Drinking Water Act Regulations from 1989-92. (MDH)

Remote Sensing of Tropospheric Pollution from Space

NASA Technical Reports Server (NTRS)

Fishman, Jack; Bowman, Kevin W.; Burrows, John P.; Chance, Kelly V.; Edwards, David P.; Martin, Randall V.; Morris, Gary A.; Pierce, R. Bradley; Ziemke, Jerald R.; Al-Saadi, Jassim A.;

Trace element biomonitoring using mosses in urban areas affected by mud volcanoes around Mt. Etna. The case of the Salinelle, Italy.

PubMed

Bonanno, Giuseppe; Lo Giudice, Rosa; Pavone, Pietro

2012-08-01

Trace element impact was assessed using mosses in a densely inhabited area affected by mud volcanoes. Such volcanoes, locally called Salinelle, are phenomena that occur around Mt. Etna (Sicily, Italy) and are interpreted as the surface outflow of a hydrothermal system located below Mt. Etna, releasing sedimentary fluids (hydrocarbons and NaCl brines) along with magmatic gases (mainly CO(2) and He). To date, scarce data are available about the presence of trace elements, and no biomonitoring campaigns are reported about the cumulative effects of such emissions. In this study, concentrations of Al, As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, V, and Zn were detected in the moss Bryum argenteum, in soil and water. Results showed that the trace element contribution of the Salinelle to the general pollution was significant for Al, Mn, Ni, and Zn. The comparison of trace concentrations in mosses from Salinelle and Etna showed that the mud volcanoes release a greater amount of Al and Mn, whereas similar values of Ni were found. Natural emissions of trace elements could be hazardous in human settlements, in particular, the Salinelle seem to play an important role in environmental pollution.

Method for quantitative determination and separation of trace amounts of chemical elements in the presence of large quantities of other elements having the same atomic mass

DOEpatents

Miller, C.M.; Nogar, N.S.

1982-09-02

Photoionization via autoionizing atomic levels combined with conventional mass spectroscopy provides a technique for quantitative analysis of trace quantities of chemical elements in the presence of much larger amounts of other elements with substantially the same atomic mass. Ytterbium samples smaller than 10 ng have been detected using an ArF* excimer laser which provides the atomic ions for a time-of-flight mass spectrometer. Elemental selectivity of greater than 5:1 with respect to lutetium impurity has been obtained. Autoionization via a single photon process permits greater photon utilization efficiency because of its greater absorption cross section than bound-free transitions, while maintaining sufficient spectroscopic structure to allow significant photoionization selectivity between different atomic species. Separation of atomic species from others of substantially the same atomic mass is also described.

Chronological protein synthesis in regenerating rat liver.

PubMed

He, Jinjun; Hao, Shuai; Zhang, Hao; Guo, Fuzheng; Huang, Lingyun; Xiao, Xueyuan; He, Dacheng

2015-07-01

Liver regeneration has been studied for decades; however, its regulation remains unclear. In this study, we report a dynamic tracing of protein synthesis in rat regenerating liver with a new proteomic technique, (35) S in vivo labeling analysis for dynamic proteomics (SiLAD). Conventional proteomic techniques typically measure protein alteration in accumulated amounts. The SiLAD technique specifically detects protein synthesis velocity instead of accumulated amounts of protein through (35) S pulse labeling of newly synthesized proteins, providing a direct way for analyzing protein synthesis variations. Consequently, protein synthesis within short as 30 min was visualized and protein regulations in the first 8 h of regenerating liver were dynamically traced. Further, the 3.5-5 h post partial hepatectomy (PHx) was shown to be an important regulatory turning point by acute regulation of many proteins in the initiation of liver regeneration. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Direct identification of trace metals in fine and ultrafine particles in the Detroit urban atmosphere.

PubMed

Utsunomiya, Satoshi; Jensen, Keld A; Keeler, Gerald J; Ewing, Rodney C

2004-04-15

Exposure to airborne particulates containing low concentrations of heavy metals, such as Pb, As, and Se, may have serious health effects. However, little is known about the speciation and particle size of these airborne metals. Fine- and ultrafine particles with heavy metals in aerosol samples from the Detroit urban area, Michigan, were examined in detail to investigate metal concentrations and speciation. The characterization of individual particles was completed using high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) combined with conventional high-resolution TEM techniques. The trace elements, Pb, As, La, Ce, Sr, Zn, Cr, Se, Sn, Y, Zr, Au, and Ag, were detected, and the elemental distributions were mapped in situ atthe nanoscale. The crystal structures of the particles containing Pb, Sr, Zn, and Au were determined from their electron diffraction patterns. Based on the characterization of the representative trace element particles, the potential health effects are discussed. Most of the trace element particles detected in this study were within a range of 0.01-1.0 microm in size, which has the longest atmospheric residence time (approximately 100 days). Increased chemical reactivity owing to the size of nanoparticles may be expected for most of the trace metal particles observed.

Effects of preoperative oral carbohydrates and trace elements on perioperative nutritional status in elective surgery patients.

PubMed

Oyama, Yoshimasa; Iwasaka, Hideo; Shiihara, Keisuke; Hagiwara, Satoshi; Kubo, Nobuhiro; Fujitomi, Yutaka; Noguchi, Takayuki

2011-10-01

In order to enhance postoperative recovery, preoperative consumption of carbohydrate (CHO) drinks has been used to suppress metabolic fluctuations. Trace elements such as zinc and copper are known to play an important role in postoperative recovery. Here, we examined the effects of preoperatively consuming a CHO drink containing zinc and copper. Subjects were 122 elective surgery patients divided into two groups (overnight fasting and CHO groups); each group was further divided into morning or afternoon surgery groups. Subjects in the CHO group consumed 300 mL of a CHO drink the night before surgery, followed by 200 ml before morning surgery or 700 ml before afternoon surgery (> or =2 hours before anesthesia induction). Blood levels of glucose, nonesterified fatty acids (NEFA), retinol-binding protein, zinc, and copper were determined. One subject in the CHO group was excluded after refusing the drink. There were no adverse effects from the CHO drink. NEFA levels increased in the fasting groups. Although zinc levels increased in the CHO group immediately after anesthesia induction, no group differences were observed the day after surgery. Preoperative consumption of a CHO drink containing trace elements suppressed preoperative metabolic fluctuations without complications and prevented trace element deficiency. Further beneficial effects during the perioperative period can be expected by adding trace elements to CHO supplements.

Concentration of trace elements on branded cigarette in Malaysia

NASA Astrophysics Data System (ADS)

Azman, Muhammad Azfar; Yasir, Muhamad Samudi; Rahman, Irman Abdul; Hamzah, Suhaimi; Rahman, Shamsiah Abdul; Elias, Md Suhaimi; Abdullah, Nazaratul Ashifa; Hashim, Azian; Shukor, Shakirah Abd

2016-01-01

Tobacco is a plant that is used as a recreational drug since the beginning of its use by the Native Americans. Now with the development of the tobacco industry, smoking has become a norm for the public in Malaysia. Trace elements in plants are mostly due to the uptake processes from the soils into the roots of the plants. The concentration of the elements may also be influenced by the elements contained in the water and also fertilizers. This paper aim to analyze the concentration of the trace elements contained in the branded cigarettes sold in Malaysia by utilizing the neutron activation analysis. The tobaccos were taken out from the cigarettes. The collected samples were air dried and passed through 2 mm sieve. Instrumental Neutron Activation Analysis (NAA) has been used for the determination of trace elements. Samples were activated in the Nuclear Malaysia Triga Mark II reactor with a neutron flux of 2.0 x 1012 n cm-2 s-1. The samples then were analyzed using ORTEC Gamma Spectrometer a co-axial n-type HPGe detector with resolution of 2.0 keV at 1332 keV and relative efficiency of 20%. The data obtained could help in assessing the concentration of the trace elements that complying with the standard limitation dose proposed by World Health Organization (WHO).

Vesicle-based method for collecting, manipulating, and chemically processing trace macromolecular species

DOEpatents

Davalos, Rafael V [Oakland, CA; Ellis, Christopher R. B. [Oakland, CA

2010-08-17

Disclosed is an apparatus and method for inserting one or several chemical or biological species into phospholipid containers that are controlled within a microfluidic network, wherein individual containers are tracked and manipulated by electric fields and wherein the contained species may be chemically processed.

Vesicle-based method and apparatus for collecting, manipulating, and chemically processing trace macromolecular species

DOEpatents

Davalos, Rafael V [Oakland, CA; Ellis, Christopher R. B. [Oakland, CA

2008-03-04

Disclosed is an apparatus and method for inserting one or several chemical or biological species into phospholipid containers that are controlled within a microfluidic network, wherein individual containers are tracked and manipulated by electric fields and wherein the contained species may be chemically processed.

BOREAS TGB-3 Plant Species Composition Data over the NSA Fen

NASA Technical Reports Server (NTRS)

Bubier, Jill L.; Hall, Forrest G. (Editor); Conrad, Sara K. (Editor)

2000-01-01

The BOReal Ecosystem-Atmosphere Study Trace Gas Biogeochemistry (BOREAS TGB-3) team collected several data sets that contributed to understanding the measured trace gas fluxes over sites in the Northern Study Area (NSA). This data set contains information about the composition of plant species that were within the collars used to measure Net Ecosystem Exchange of CO2 (NEE). The species composition was identified to understand the differences in NEE among the various plant communities in the NSA fen. The data were collected in July of 1994 and 1996. The data are contained in comma-delimited, ASCII files.

Meteoritic trace element toxification and the terminal Mesozoic mass extinction

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

Dickson, S.M.; Erickson, D.J. III

1985-01-01

Calculations of trace element fluxes to the earth associated with 5 and 10 kilometer diameter Cl chondrites and iron meteorites are presented. The data indicate that the masses of certain trace elements contained in the bolide, such as Fe, Co, Ni, Cr, Pb, and Cu, are as large as or larger than the world ocean burden. The authors believe that this pulse of trace elements was of sufficient magnitude to perturb the biogeochemical cycles operative 65 million years ago, a probably time of meteorite impact. Geochemical anomalies in Cretaceous-Tertiary boundary sediments suggest that elevated concentrations of trace elements may havemore » persisted for thousands of years in the ocean. Through direct exposure and bioaccumulation, many trophic levels of the global food chain, including that of the dinosaurs, would have been adversely affected by these meteoritic trace elements. The trace element toxification hypothesis may account for the selective extinction of both marine and terrestrial species in the enigmatic terminal Mesozoic event.« less

Trace element abundances of high-MgO glasses from Kilauea, Mauna Loa and Haleakala volcanoes, Hawaii

USGS Publications Warehouse

Wagner, T.P.; Clague, D.A.; Hauri, E.H.; Grove, T.L.

1998-01-01

We performed an ion-microprobe study of eleven high-MgO (6.7-14.8 wt%) tholeiite glasses from the Hawaiian volcanoes Kilauea, Mauna Loa and Haleakala. We determined the rare earth (RE), high field strength, and other selected trace element abundances of these glasses, and used the data to establish their relationship to typical Hawaiian shield tholeiite and to infer characteristics of their source. The glasses have trace element abundance characteristics generally similar to those of typical shield tholeiites, e.g. L(light)REE/H(heavy)REE(C1) > 1. The Kilauea and Mauna Loa glasses, however, display trace and major element characteristics that cross geochemical discriminants observed between Kilauea and Mauna Loa shield lavas. The glasses contain a blend of these discriminating chemical characteristics, and are not exactly like the typical shield lavas from either volcano. The production of these hybrid magmas likely requires a complexly zoned source, rather than two unique sources. When corrected for olivine fractionation, the glass data show correlations between CaO concentration and incompatible trace element abundances, indicating that CaO may behave incompatibly during melting of the tholeiite source. Furthermore, the tholeiite source must contain residual garnet and clinopyroxene to account for the variation in trace element abundances of the Kilauea glasses. Inversion modeling indicates that the Kilauea source is flat relative to C1 chondrites, and has a higher bulk distribution coefficient for the HREE than the LREE.

Application of cotton as a solid phase extraction sorbent for on-line preconcentration of copper in water samples prior to inductively coupled plasma optical emission spectrometry determination.

PubMed

Faraji, Mohammad; Yamini, Yadollah; Shariati, Shahab

2009-07-30

Copper, as a heavy metal, is toxic for many biological systems. Thus, the determination of trace amounts of copper in environmental samples is of great importance. In the present work, a new method was developed for the determination of trace amounts of copper in water samples. The method is based on the formation of ternary Cu(II)-CAS-CTAB ion-pair and adsorption of it into a mini-column packed with cotton prior applying inductively coupled plasma optical emission spectrometry (ICP-OES). The experimental parameters that affected the extraction efficiency of the method such as pH, flow rate and volume of the sample solution, concentration of chromazurol S (CAS) and cethyltrimethylammonium bromide (CTAB) as well as type and concentration of eluent were investigated and optimized. The ion-pair (Cu(II)-CAS-CTAB) was quantitatively retained on the cotton under the optimum conditions, then eluted completely using a solution of 25% (v/v) 1-propanol in 0.5 mol L(-1) HNO(3) and directly introduced into the nebulizer of the ICP-OES. The detection limit (DL) of the method for copper was 40 ng L(-1) (V(sample)=100mL) and the relative standard deviation (R.S.D.) for the determination of copper at 10 microg L(-1) level was found to be 1.3%. The method was successfully applied to determine the trace amounts of copper in tap water, deep well water, seawater and two different mineral waters, and suitable recoveries were obtained (92-106%).

A solid-phase extraction method using Transcarpathian clinoptilolite for preconcentration of trace amounts of terbium in water samples.

PubMed

Vasylechko, Volodymyr O; Gryshchouk, Galyna V; Zakordonskiy, Victor P; Vyviurska, Olga; Pashuk, Andriy V

2015-01-01

In spite of the fact that terbium is one of the rarest elements in the Earth's crust, it is frequently used for the production of high technological materials. At the result, an effective combination of sample preparation procedure and detection method for terbium ions in different matrices is highly required. The solid-phase extraction procedure with natural Transcarpathian clinoptilolite thermally activated at 350 °C was used to preconcentrate trace amounts of terbium ions in aqueous solutions for a final spectrophotometric determination with arsenazo III. Thermogravimetric investigations confirmed the existence of relations between changes that appeared during dehydratation of calcined zeolite and its sorption affinity. Since the maximum of sorption capacity towards terbium was observed at pH 8.25, a borate buffer medium (2.5 · 10(-4) М) was used to maintain ionic force and solution acidity. Terbium was quantitatively removed from the solid-phase extraction column with a 1.0 M solution of sodium chloride (pH 2.5). The linearity of the proposed method was evaluated in the range of 2.5-200 ng · mL(-1) with detection limit 0.75 ng · mL(-1). Due to acceptable recoveries (93.3-102.0 %) and RSD values (6-7.1) from spiked tap water, the developed method can be successfully applied for the determination of trace amounts of terbium ions in the presence of major components of water. Graphical abstractSorption of terbium(III) ions on clinoptilolite.

The rodent Research Animal Holding Facility as a barrier to environmental contamination

NASA Technical Reports Server (NTRS)

Savage, P. D., Jr.; Jahns, G. C.; Dalton, B. P.; Hogan, R. P.; Wray, A. E.

1989-01-01

The rodent Research Animal Holding Facility (RAHF), developed by NASA Ames Research Center (ARC) to separately house rodents in a Spacelab, was verified as a barrier to environmental contaminants during a 12-day biocompatibility test. Environmental contaminants considered were solid particulates, microorganisms, ammonia, and typical animal odors. The 12-day test conducted in August 1988 was designed to verify that the rodent RAHF system would adequately support and maintain animal specimens during normal system operations. Additional objectives of this test were to demonstrate that: (1) the system would capture typical particulate debris produced by the animal; (2) microorganisms would be contained; and (3) the passage of animal odors was adequately controlled. In addition, the amount of carbon dioxide exhausted by the RAHF system was to be quantified. Of primary importance during the test was the demonstration that the RAHF would contain particles greater than 150 micrometers. This was verified after analyzing collection plates placed under exhaust air ducts and and rodent cages during cage maintenance operations, e.g., waste tray and feeder changeouts. Microbiological testing identified no additional organisms in the test environment that could be traced to the RAHF. Odor containment was demonstrated to be less than barely detectable. Ammonia could not be detected in the exhaust air from the RAHF system. Carbon dioxide levels were verified to be less than 0.35 percent.

The rodent research animal holding facility as a barrier to environmental contamination

NASA Technical Reports Server (NTRS)

Savage, P. D., Jr.; Jahns, G. C.; Dalton, B. P.; Hogan, R. P.; Wray, A. E.

1989-01-01

The rodent Research Animal Holding Facility (RAHF), developed by NASA Ames Research Center (ARC) to separately house rodents in a Spacelab, was verified as a barrier to environmental contaminants during a 12-day biocompatibility test. Environmental contaminants considered were solid particulates, microorganisms, ammonia, and typical animal odors. The 12-day test conducted in August 1988 was designed to verify that the rodent RAHF system would adequately support and maintain animal specimens during normal system operations. Additional objectives of this test were to demonstrate that: (1) the system would capture typical particulate debris produced by the animal; (2) microorganisms would be contained; and (3) the passage of animal odors was adequately controlled. In addition, the amount of carbon dioxide exhausted by the RAHF system was to be quantified. Of primary importance during the test was the demonstration that the RAHF would contain particles greater than 150 micrometers. This was verified after analyzing collection plates placed under exhaust air ducts and rodent cages during cage maintenance operations, e.g., waste tray and feeder changeouts. Microbiological testing identified no additional organisms in the test environment that could be traced to the RAHF. Odor containment was demonstrated to be less than barely detectable. Ammonia could not be detected in the exhaust air from the RAHF system. Carbon dioxide levels were verified to be less than 0.35 percent.

Manufacturing Amorphous Solid Dispersions with a Tailored Amount of Crystallized API for Biopharmaceutical Testing.

PubMed

Theil, Frank; Milsmann, Johanna; Anantharaman, Sankaran; van Lishaut, Holger

2018-05-07

The preparation of an amorphous solid dispersion (ASD) by dissolving a poorly water-soluble active pharmaceutical ingredient (API) in a polymer matrix can improve the bioavailability by orders of magnitude. Crystallization of the API in the ASD, though, is an inherent threat for bioavailability. Commonly, the impact of crystalline API on the drug release of the dosage form is studied with samples containing spiked crystallinity. These spiked samples possess implicit differences compared to native crystalline samples, regarding size and spatial distribution of the crystals as well as their molecular environment. In this study, we demonstrate that it is possible to grow defined amounts of crystalline API in solid dosage forms, which enables us to study the biopharmaceutical impact of actual crystallization. For this purpose, we studied the crystal growth in fenofibrate tablets over time under an elevated moisture using transmission Raman spectroscopy (TRS). As a nondestructive method to assess API crystallinity in ASD formulations, TRS enables the monitoring of crystal growth in individual dosage forms. Once the kinetic trace of the crystal growth for a certain environmental condition is determined, this method can be used to produce samples with defined amounts of crystallized API. To investigate the biopharmaceutical impact of crystallized API, non-QC dissolution methods were used, designed to identify differences between the various amounts of crystalline materials present. The drug release in the samples manufactured in this fashion was compared to that of samples with spiked crystallinity. In this study, we present for the first time a method for targeted crystallization of amorphous tablets to simulate crystallized ASDs. This methodology is a valuable tool to generate model systems for biopharmaceutical studies on the impact of crystallinity on the bioavailability.

Determination of minor and trace elements in aromatic spices by micro-wave assisted digestion and inductively coupled plasma-mass spectrometry.

PubMed

Khan, Naeem; Choi, Ji Yeon; Nho, Eun Yeong; Jamila, Nargis; Habte, Girum; Hong, Joon Ho; Hwang, In Min; Kim, Kyong Su

2014-09-01

This study aimed at analyzing the concentrations of 23 minor and trace elements in aromatic spices by inductively coupled plasma-mass spectrometry (ICP-MS), after wet digestion by microwave system. The analytical method was validated by linearity, detection limits, precision, accuracy and recovery experiments, obtaining satisfactory values in all cases. Results indicated the presence of variable amounts of both minor and trace elements in the selected aromatic spices. Manganese was high in cinnamon (879.8 μg/g) followed by cardamom (758.1 μg/g) and clove (649.9 μg/g), strontium and zinc were high in ajwain (489.9 μg/g and 84.95 μg/g, respectively), while copper was high in mango powder (77.68 μg/g). On the whole some of the minor and essential trace elements were found to have good nutritional contribution in accordance to RDA. The levels of toxic trace elements, including As, Cd, and Pb were very low and did not found to pose any threat to consumers. Copyright © 2014 Elsevier Ltd. All rights reserved.

Infrared trace element detection system

DOEpatents

Bien, F.; Bernstein, L.S.; Matthew, M.W.

1988-11-15

An infrared trace element detection system includes an optical cell into which the sample fluid to be examined is introduced and removed. Also introduced into the optical cell is a sample beam of infrared radiation in a first wavelength band which is significantly absorbed by the trace element and a second wavelength band which is not significantly absorbed by the trace element for passage through the optical cell through the sample fluid. The output intensities of the sample beam of radiation are selectively detected in the first and second wavelength bands. The intensities of a reference beam of the radiation are similarly detected in the first and second wavelength bands. The sensed output intensity of the sample beam in one of the first and second wavelength bands is normalized with respect to the other and similarly, the intensity of the reference beam of radiation in one of the first and second wavelength bands is normalized with respect to the other. The normalized sample beam intensity and normalized reference beam intensity are then compared to provide a signal from which the amount of trace element in the sample fluid can be determined. 11 figs.

Infrared trace element detection system

DOEpatents

Bien, Fritz; Bernstein, Lawrence S.; Matthew, Michael W.

1988-01-01

An infrared trace element detection system including an optical cell into which the sample fluid to be examined is introduced and removed. Also introduced into the optical cell is a sample beam of infrared radiation in a first wavelength band which is significantly absorbed by the trace element and a second wavelength band which is not significantly absorbed by the trace element for passage through the optical cell through the sample fluid. The output intensities of the sample beam of radiation are selectively detected in the first and second wavelength bands. The intensities of a reference beam of the radiation are similarly detected in the first and second wavelength bands. The sensed output intensity of the sample beam in one of the first and second wavelength bands is normalized with respect to the other and similarly, the intensity of the reference beam of radiation in one of the first and second wavelength bands is normalized with respect to the other. The normalized sample beam intensity and normalized reference beam intensity are then compared to provide a signal from which the amount of trace element in the sample fluid can be determined.

Choline and Inositol Distribution in Algae and Fungi1

PubMed Central

Ikawa, Miyoshi; Borowski, Paul T.; Chakravarti, Ashima

1968-01-01

Inositol and choline were present in varying amounts among the species of Rhodophyta, Phaeophyta, Chlorophyta, and Euglenophyta examined. However, in the two members of the order Fucales (division Phaeophyta) examined, no detectable amounts of choline were found. In contrast, the species of Cyanophyta examined contained no detectable amounts of either choline or inositol. All species of the fungal classes Phycomyceteae, Ascomyceteae, and Basidiomyceteae collected contained both inositol and choline in varying amounts. The red, brown, and blue-green algae usually contained much less inositol and choline than do plant and animals sources, but the fungi and the algae Chlorella and Euglena contained amounts comparable to those present in plant sources. PMID:5647522

Optimal conditions for elution of hepatitis B antigen after absorption onto colloidal silica.

PubMed Central

Pillot, J; Goueffon, S; Keros, R G

1976-01-01

Hepatitis B surface antigen (HBSAg) adsorbed from sera onto colloidal silica could be completely eluted through the use of 0.25% sodium deoxycholate in 0.01 M borax, pH 9.3, at 56 degrees C. The HBSAg recovered in the eluate represented 100% of that present in the original serum, and it was contaminated by only trace amounts of serum proteins (in decreasing amounts: beta-lipoprotein, immunoglobulin G, albumin). This preliminary step greatly facilitates purification of large amounts of HBSAg and provides small volumes of highly concentrated material for subsequent purification by density gradient centrifugation. PMID:9423

Trace detection of analytes using portable raman systems

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

Alam, M. Kathleen; Hotchkiss, Peter J.; Martin, Laura E.

Apparatuses and methods for in situ detection of a trace amount of an analyte are disclosed herein. In a general embodiment, the present disclosure provides a surface-enhanced Raman spectroscopy (SERS) insert including a passageway therethrough, where the passageway has a SERS surface positioned therein. The SERS surface is configured to adsorb molecules of an analyte of interest. A concentrated sample is caused to flow over the SERS surface. The SERS insert is then provided to a portable Raman spectroscopy system, where it is analyzed for the analyte of interest.

Trace metal analysis by laser ablation-inductively coupled plasmamass spectrometry and x-ray K-edge densitometry of forensic samples

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

Berry, Jonna Elizabeth

This dissertation describes a variety of studies on the determination of trace elements in samples with forensic importance. Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) was used to determine the trace element composition of numerous lipstick samples. Lipstick samples were determined to be homogeneous. Most lipstick samples of similar colors were readily distinguishable at a 95% confidence interval based on trace element composition. Numerous strands of a multi-strand speaker cable were analyzed by LA-ICP-MS. The strands in this study are spatially heterogeneous in trace element composition. In actual forensic applications, the possibility of spatial heterogeneity must be considered, especially in casesmore » where only small samples (e.g., copper wire fragments after an explosion) are available. The effects of many unpredictable variables, such as weather, temperature, and human activity, on the retention of gunshot residue (GSR) around projectile wounds were assessed with LAICP- MS. Skin samples around gunshot and stab wounds and larvae feeding in and around the wounds on decomposing pig carcasses were analyzed for elements consistent with GSR (Sb, Pb, Ba, and Cu). These elements were detected at higher levels in skin and larvae samples around the gunshot wounds compared to the stab wounds for an extended period of time throughout decomposition in both a winter and summer study. After decomposition, radiographic images of the pig bones containing possible damage from bullets revealed metallic particles embedded within a number of bones. Metallic particles within the bones were analyzed with x-ray, K-edge densitometry and determined to contain lead, indicating that bullet residue can be retained throughout decomposition and detected within bones containing projectile trauma.« less

Helium Find Thaws the Cold Fusion Trail.

ERIC Educational Resources Information Center

Pennisi, E.

1991-01-01

Reported is a study of cold fusion in which trace amounts of helium, possible evidence of an actual fusion reaction, were found. Research methodology is detailed. The controversy over the validity of experimental results with cold fusion are reviewed. (CW)

Trace metals in liver from bluefish, tautog, and tilefish in relation to body length

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

Mears, H.C.; Eisler, R.

1977-09-01

Livers from bluefish, tilefish and tautog collected during the summer of 1971 off the New Jersey coast were analyzed for Cd, Cr, Cu, Fe, Mn, Ni, and Zn by atomic absorption spectrophotometry. Liver ash from male and female tautog contained decreasing concentrations of Ni with increasing body length. Smaller males also contained greater levels of Cr and Cu in liver than larger tautogs. Larger tilefish contained proportionately more Cd, Cu, and Fe in liver than smaller tilefish. Decreasing levels of Mn and Zn with body length were apparent only for females. Livers from larger male bluefish were associated with highermore » concentrations of Fe than those from smaller males, while those from larger females contained lower concentrations of Cr than those from smaller females. The data suggest that future comparisons for trace metals which vary as a function of size be made only among fish of the same length.« less

Water recovery in a concentrated solar power plant

NASA Astrophysics Data System (ADS)

Raza, Aikifa; Higgo, Alex R.; Alobaidli, Abdulaziz; Zhang, TieJun

2016-05-01

For CSP plants, water consumption is undergoing increasing scrutiny particularly in dry and arid regions with water scarcity conditions. Significant amount of water has to be used for parabolic trough mirror cleaning to maintain high mirror reflectance and optical efficiency in sandy environment. For this specific purpose, solar collectors are washed once or twice every week at Shams 1, one of the largest CSP plant in the Middle East, and about 5 million gallons of demineralized water is utilized every year without further recovery. The produced waste water from a CSP plant contains the soiling i.e. accumulated dust and some amount of organic contaminants, as indicated by our analysis of waste water samples from the solar field. We thus need to develop a membrane based system to filter fine dust particulates and to degrade organic contaminant simultaneously. Membrane filtration technology is considered to be cost-effective way to address the emerging problem of a clean water shortage, and to reuse the filtered water after cleaning solar collectors. But there are some major technical barriers to improve the robustness and energy efficiency of filtration membranes especially when dealing with the removal of ultra-small particles and oil traces. Herein, we proposed a robust and scalable nanostructured inorganic microporous filtration copper mesh. The inorganic membrane surface wettability is tailored to enhance the water permeability and filtration flux by creating nanostructures. These nanostructured membranes were successfully employed to recover water collected after cleaning the reflectors of solar field of Shams 1. Another achievement was to remove the traces of heat transfer fluid (HTF) from run-off water which was collected after accidental leakage in some of the heat exchangers during the commissioning of the Shams 1 for safe disposal into the main stream. We hope, by controlling the water recovery factor and membrane reusability performance, the membrane design could be used for water conservation in CSP plants.

Understanding the Marine Chromium Isotope Record from Modern and Ancient Carbonates

NASA Astrophysics Data System (ADS)

Parkinson, I. J.; Bonnand, P.; James, R. H.; Fairchild, I. J.; Dixon, S.

2011-12-01

Chromium isotopes may provide a powerful tool for reconstructing the redox state of ancient seawater because Cr isotope fractionation is large (up to 7% in δ53Cr) during the reduction of Cr(VI) to Cr(III) in natural waters [1]. Recent studies have demonstrated that although Cr(VI) is predicted to be the thermodynamically stable form in seawater (as CrO42-), significant amounts (5-20%) of Cr(III) may also be present in surface waters [2]. Therefore the δ53Cr of seawater could vary by up to 2%. Marine carbonates potentially provide a means to extracting information about the Cr isotopic composition of seawater in the geological past and we have developed a high-precision double-spike technique for analysing Cr isotopes in carbonates [3]. The δ53Cr of modern Bahamas Bank carbonates (+0.76%) is broadly consistent with these carbonates recording a seawater Cr signature. Moreover, these pure carbonates contain significant amounts of Cr (1-4 ppm), which indicates that Cr is strongly partitioned into calcium carbonate. Therefore carbonates are likely to provide a faithful record of the δ53Cr composition of seawater. Shallow marine carbonates from the Phanerozoic range in δ53Cr from +0.76 to +1.8%, and some Neoproterozoic carbonates also have heavy Cr isotopic compositions of +0.5 to +1.0 %. Such compositions may reflect changes in the inputs of Cr to the oceans and/or changes in the redox state of the oceans. However, to interpret Cr isotopic compositions in ancient carbonates additionally requires a careful assessment of their trace element contents. This study aims to demonstrate how a combination of redox sensitive trace elements, such as Ce, and Cr isotopes allow an assessment of the marine chromium isotope record. [1] Ellis et al., 2002, Science, 295, 2060-2062. [2] Connolly et al., 2006, Deep Sea Res. Part I, 2006 53, 1975-1988. [3] P. Bonnand, et al., 2011, J. Anal. At. Spectr., 26, 528-535.

Relationships Between HED's, Mesosiderites, and Ungrouped Achondrites: Trace Element Analyses of Mesosiderite RKPA 79015 and Ungrouped Achondrite QUE 93148

NASA Technical Reports Server (NTRS)

Righter, M.; Lapen, T.; Righter, K.

2008-01-01

Achondritic meteorites are a diverse group of meteorites that formed by igneous activity in asteroids. These meteorites can provide important information about early differentiation processes on asteroidal bodies. The howardite-eucrite-diogenite (HED) meteorites, the largest group of achondrites, are the only group of meteorites for which a potential parent body has been identified (4 Vesta) [e.g., 1]. Mesosiderites are stony-iron meteorites composed of roughly equal amounts of metal and silicates and silicates are broadly similar to HED meteorites [2]. They may have been formed by impact-mixing of crustal and core materials of differentiated meteorite parent bodies. Chemical and oxygen isotopic compositional data suggest that the HED meteorites and silicate portions of mesosiderites originated on the same or closely related parent bodies. Pallasites and IIIAB irons also have similar oxygen isotope compositions and have been thought to be related to the HEDs [3,4]. However, recent high resolution analyses have shown that pallasites and HED's have different oxygen isotopic values, but mesosiderites and HED s have the same isotope compositions implying a close connection [5]. QUE 93148 is a small (1.1g) olivine-rich (mg 86) achondrite that contains variable amounts of orthopyroxenene (mg 87) and kamacite (6.7 wt% Ni), with minor augite [6]. This meteorite was originally classified as a lodranite [7], but it s oxygen isotopic composition precludes a genetic relationship to the acapulcoites and lodranites. And also this meteorite has a lower Mn/Mg ratio than any major group of primitive or evolved achondrites and suggested that QUE 93148 may be a piece of the deep mantle of the HED parent body [6]. To better understand the relationship between HED s, mesosiderites and related achondrites, we have measured trace elements in the individual metallic and silicate phases. In this study, abundances of a suite of elements were measured for the unusual mesosiderite RKPA 79015 and a ungrouped achondrite QUE93148.

A Novel In Vitro Method for Detecting Undifferentiated Human Pluripotent Stem Cells as Impurities in Cell Therapy Products Using a Highly Efficient Culture System

PubMed Central

Tano, Keiko; Yasuda, Satoshi; Kuroda, Takuya; Saito, Hirohisa; Umezawa, Akihiro; Sato, Yoji

2014-01-01

Innovative applications of cell therapy products (CTPs) derived from human pluripotent stem cells (hPSCs) in regenerative medicine are currently being developed. The presence of residual undifferentiated hPSCs in CTPs is a quality concern associated with tumorigencity. However, no simple in vitro method for direct detection of undifferentiated hPSCs that contaminate CTPs has been developed. Here, we show a novel approach for direct and sensitive detection of a trace amount of undifferentiated human induced pluripotent stem cells (hiPSCs) using a highly efficient amplification method in combination with laminin-521 and Essential 8 medium. Essential 8 medium better facilitated the growth of hiPSCs dissociated into single cells on laminin-521 than in mTeSR1 medium. hiPSCs cultured on laminin-521 in Essential 8 medium were maintained in an undifferentiated state and they maintained the ability to differentiate into various cell types. Essential 8 medium allowed robust hiPSC proliferation plated on laminin-521 at low cell density, whereas mTeSR1 did not enhance the cell growth. The highly efficient culture system using laminin-521 and Essential 8 medium detected hiPSCs spiked into primary human mesenchymal stem cells (hMSCs) or human neurons at the ratio of 0.001%–0.01% as formed colonies. Moreover, this assay method was demonstrated to detect residual undifferentiated hiPSCs in cell preparations during the process of hMSC differentiation from hiPSCs. These results indicate that our highly efficient amplification system using a combination of laminin-521 and Essential 8 medium is able to detect a trace amount of undifferentiated hPSCs contained as impurities in CTPs and would contribute to quality assessment of hPSC-derived CTPs during the manufacturing process. PMID:25347300

Electrochemical Behavior of Sn-9Zn-xTi Lead-Free Solders in Neutral 0.5M NaCl Solution

NASA Astrophysics Data System (ADS)

Wang, Zhenghong; Chen, Chuantong; Jiu, Jinting; Nagao, Shijo; Nogi, Masaya; Koga, Hirotaka; Zhang, Hao; Zhang, Gong; Suganuma, Katsuaki

2018-03-01

Electrochemical techniques were employed to study the electrochemical corrosion behavior of Sn-9Zn-xTi (x = 0, 0.05, 0.1, 0.2 wt.%) lead-free solders in neutral 0.5M NaCl solution, aiming to figure out the effect of Ti content on the corrosion properties of Sn-9Zn, providing information for the composition design of Sn-Zn-based lead-free solders from the perspective of corrosion. EIS results reveal that Ti addition was involved in the corrosion product layer and changed electrochemical interface behavior from charge transfer control process to diffusion control process. The trace amount of Ti addition (0.05 wt.%) can refine the microstructure and improve the corrosion resistance of Sn-9Zn solder, evidenced by much lower corrosion current density (i corr) and much higher total resistance (R t). Excess Ti addition (over 0.1 wt.%) led to the formation of Ti-containing IMCs, which were confirmed as Sn3Ti2 and Sn5Ti6, deteriorating the corrosion resistance of Sn-9Zn-xTi solders. The main corrosion products were confirmed as Sn3O(OH)2Cl2 mixed with small amount of chlorine/oxide Sn compounds.

Identification and reduction of urinary aflatoxin metabolites in dogs.

PubMed

Bingham, A K; Huebner, H J; Phillips, T D; Bauer, J E

2004-11-01

Hydrated sodium calcium aluminosilicate (HSCAS) is a phyllosilicate clay commonly used as an anticaking agent in animal feeds. HSCAS tightly and selectively adsorbs aflatoxin. In 1998, 55 dogs died in Texas after eating dog food containing aflatoxin (150-300 ppb). The corn in the diets was contaminated with aflatoxin. Six dogs were given a low-level, sub-clinical dose of aflatoxin B(1). On average, 71.5% of aflatoxin M(1) cleared within 6 h after dosing, increasing to 90.4% after 12 h. Aflatoxin M(1) was no longer detectable in urine after 48 h. Aflatoxin P(1) was not found in urine compared to large amounts of M(1) and trace amounts of Q(1). In a crossover study, six dogs randomly fed a commercial dog food (no-clay control) or coated with HSCAS (0.5% by weight) were subsequently administered a sub-clinical dose of aflatoxin B(1). Diets were switched and the process repeated. The HSCAS-coated diet significantly reduced urinary aflatoxin M(1) by 48.4%+/-16.6 SD versus the control diet. In conclusion, HSCAS protects dogs fed diets with even minimal aflatoxin contamination. Despite regular and careful ingredient screening for aflatoxin, low concentrations may reach the final product undetected. Therefore, HSCAS may provide the pet food industry further assurance of canine diet safety.

Electrochemical Behavior of Sn-9Zn- xTi Lead-Free Solders in Neutral 0.5M NaCl Solution

NASA Astrophysics Data System (ADS)

Wang, Zhenghong; Chen, Chuantong; Jiu, Jinting; Nagao, Shijo; Nogi, Masaya; Koga, Hirotaka; Zhang, Hao; Zhang, Gong; Suganuma, Katsuaki

2018-05-01

Electrochemical techniques were employed to study the electrochemical corrosion behavior of Sn-9Zn- xTi ( x = 0, 0.05, 0.1, 0.2 wt.%) lead-free solders in neutral 0.5M NaCl solution, aiming to figure out the effect of Ti content on the corrosion properties of Sn-9Zn, providing information for the composition design of Sn-Zn-based lead-free solders from the perspective of corrosion. EIS results reveal that Ti addition was involved in the corrosion product layer and changed electrochemical interface behavior from charge transfer control process to diffusion control process. The trace amount of Ti addition (0.05 wt.%) can refine the microstructure and improve the corrosion resistance of Sn-9Zn solder, evidenced by much lower corrosion current density ( i corr) and much higher total resistance ( R t). Excess Ti addition (over 0.1 wt.%) led to the formation of Ti-containing IMCs, which were confirmed as Sn3Ti2 and Sn5Ti6, deteriorating the corrosion resistance of Sn-9Zn- xTi solders. The main corrosion products were confirmed as Sn3O(OH)2Cl2 mixed with small amount of chlorine/oxide Sn compounds.

Application of a thiourea-containing task-specific ionic liquid for the solid-phase extraction cleanup of lead ions from red lipstick, pine leaves, and water samples.

PubMed

Saljooqi, Asma; Shamspur, Tayebeh; Mohamadi, Maryam; Mostafavi, Ali

2014-07-01

Here, task-specific ionic liquid solid-phase extraction is proposed for the first time. In this approach, a thiourea-functionalized ionic liquid is immobilized on the solid sorbent, multiwalled carbon nanotubes. These modified nanotubes packed into a solid-phase extraction column are used for the selective extraction and preconcentration of ultra-trace amounts of lead(II) from aqueous samples prior to electrothermal atomic absorption spectroscopy determination. The thiourea functional groups act as chelating agents for lead ions retaining them and so, give the selectivity to the sorbent. Elution of the retained ions can be performed using an acidic thiourea solution. The effects of experimental parameters including pH of the aqueous solution, type and amount of eluent, and the flow rates of sample and eluent solutions on the separation efficiency are investigated. The linear dependence of absorbance of lead on its concentration in the initial solution is in the range of 0.5-40.0 ng/mL with the detection limit of 0.13 ng/mL (3(Sb)/m, n = 10). The proposed method is applicable to the analysis of red lipstick, pine leaves, and water samples for their lead contents. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Effect of copper chloride on the emissions of PCDD/Fs and PAHs from PVC combustion.

PubMed

Wang, Dongli; Xu, Xiaobai; Zheng, Minghui; Chiu, Chung H

2002-09-01

The influences of temperature, air flow and the amount of copper chloride upon the types and amount of the toxic emissions such as polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) and polycyclic aromatic hydrocarbons (PAHs) during combustion of polyvinyl chloride (PVC) were investigated. The mechanism concerning the effect of temperature and copper chloride on the PCDD/Fs and PAHs formation was discussed. The results shown that without copper chloride, trace amounts of PCDD/Fs and large amounts of PAHs were found in the emissions from the pure PVC combustion under various combustion conditions. The addition of copper chloride enhanced PCDD/Fs formation, but it seems that the formation of PAHs decreased with increasing amount of copper chloride, and greater total amount of PAHs were produced at the higher temperature under our experimental conditions.

SolTrace FAQs | Concentrating Solar Power | NREL

Science.gov Websites

that should be noted: when using a cubic spline file to describe a surface, if that file contains a help for script functions? A: Yes, when typing a script function within the scripting window, as you results. When the limit is reached, SolTrace generates the following error message (Windows version; Mac

Assessing Students' Ability to Trace Matter in Dynamic Systems in Cell Biology

ERIC Educational Resources Information Center

Wilson, Christopher D.; Anderson, Charles W.; Heidemann, Merle; Merrill, John E.; Merritt, Brett W.; Richmond, Gail; Sibley, Duncan F.; Parker, Joyce M.

2006-01-01

College-level biology courses contain many complex processes that are often taught and learned as detailed narratives. These processes can be better understood by perceiving them as dynamic systems that are governed by common fundamental principles. Conservation of matter is such a principle, and thus tracing matter is an essential step in…

Neutron activation analyses and half-life measurements at the usgs triga reactor

NASA Astrophysics Data System (ADS)

Larson, Robert E.

Neutron activation of materials followed by gamma spectroscopy using high-purity germanium detectors is an effective method for making measurements of nuclear beta decay half-lives and for detecting trace amounts of elements present in materials. This research explores applications of neutron activation analysis (NAA) in two parts. Part 1. High Precision Methods for Measuring Decay Half-Lives, Chapters 1 through 8 Part one develops research methods and data analysis techniques for making high precision measurements of nuclear beta decay half-lives. The change in the electron capture half-life of 51Cr in pure chromium versus chromium mixed in a gold lattice structure is explored, and the 97Ru electron capture decay half-life are compared for ruthenium in a pure crystal versus ruthenium in a rutile oxide state, RuO2. In addition, the beta-minus decay half-life of 71mZn is measured and compared with new high precision findings. Density Functional Theory is used to explain the measured magnitude of changes in electron capture half-life from changes in the surrounding lattice electron configuration. Part 2. Debris Collection Nuclear Diagnostic at the National Ignition Facility, Chapters 9 through 11 Part two explores the design and development of a solid debris collector for use as a diagnostic tool at the National Ignition Facility (NIF). NAA measurements are performed on NIF post-shot debris collected on witness plates in the NIF chamber. In this application NAA is used to detect and quantify the amount of trace amounts of gold from the hohlraum and germanium from the pellet present in the debris collected after a NIF shot. The design of a solid debris collector based on material x-ray ablation properties is given, and calculations are done to predict performance and results for the collection and measurements of trace amounts of gold and germanium from dissociated hohlraum debris.

Arsenic bioaccumulation and biotransformation in deep-sea hydrothermal vent organisms from the PACMANUS hydrothermal field, Manus Basin, PNG

NASA Astrophysics Data System (ADS)

Price, Roy E.; Breuer, Christian; Reeves, Eoghan; Bach, Wolfgang; Pichler, Thomas

2016-11-01

Hydrothermal vents are often enriched in arsenic, and organisms living in these environments may accumulate high concentrations of this and other trace elements. However, very little research to date has focused on understanding arsenic bioaccumulation and biotransformation in marine organisms at deep-sea vent areas; none to date have focused organisms from back-arc spreading centers. We present for the first time concentration and speciation data for As in vent biota from several hydrothermal vent fields in the eastern Manus basin, a back-arc basin vent field located in the Bismark Sea, western Pacific Ocean. The gastropods Alviniconcha hessleri and Ifremeria nautilei, and the mussel Bathymodiolus manusensis were collected from diffuse venting areas where pH was slightly lower (6.2-6.8), and temperature (26.8-10.5 °C) and arsenic concentrations (169.5-44.0 nM) were higher than seawater. In the tissues of these organisms, the highest total measured As concentrations were in the gills of A. hessleri (5580 mg kg-1), with 721 mg kg-1 and 43 mg kg-1 in digestive gland and muscle, respectively. I. nautilei contained 118 mg kg-1 in the gill, 108 mg kg-1 in the digestive gland and 22 mg kg-1 in the muscle. B. manusensis contained 15.7 mg kg-1 in the digestive gland, followed by 9.8 mg kg-1 and 4.5 mg kg-1 in its gill and muscle tissue, respectively. We interpret the decreasing overall total concentrations in each organism as a function of distance from the source of hydrothermally derived As. The high concentration of arsenic in A. hessleri gills may be associated with elemental sulfur known to occur in this organism as a result of symbiotic microorganisms. Arsenic extracted from freeze-dried A. hessleri tissue was dominated by AsIII and AsV in the digestive gland (82% and 16%, respectively) and gills (97% AsIII, 2.3% AsV), with only 1.8% and 0.2% arsenobetaine (As-Bet) in the digestive gland and gills, respectively. However, the muscle contained substantial amounts of As-Bet (42% As-Bet compared to 48% AsIII and 10% AsV), suggesting As-Bet is a metabolite. Trace arsenosugar (SO4-sug) was observed in digestive gland and gills only. The other snail, I. nautilei, was also dominated by AsIII and AsV in digestive glands (82, 10%) and gills (80, 10%), with 6-9% As-Bet, but its muscle contained 62% As-Bet and 32% AsIII, with 7% trimethylarsoniopropionate (TMAP). Trace dimethylarsinic acid (DMAV) was observed in its gills, and trace TMAP and arsenocholine (AC) was observed in digestive glands. The mussel B. manusensis was dominated by As-Bet in all three tissue types. Digestive gland and gills contained 22% AsIII, 5-10% AsV, 20-25% DMAV, along with some TMAP and tetramethylarsonium ion (TETRA). However, the muscle contained significantly more As-Bet (91.6%), with the only other species being AsIII (8.4%). Unfortunately, as is often the case in bioaccumulation and biotransformation studies, extraction efficiencies were low, limiting any rigorous interpretation of arsenic biotransformation patterns. Through process of elimination, we suggest that arsenosugars may be synthesized by H2S-oxidizing chemotrophic microbial mats, ultimately leading to the syntheses of As-Bet within vent organisms. However, because As-sugs rarely occur in deep-sea vent organisms, As-Bet, as well as TMAP, AC, and TETRA could also potentially be synthesized directly by the "Edmonds" pathway, the proposed arseno-analog to amino acid formation, without the necessity for arsenosugar formation as an intermediate. Future research should endeavor for more comprehensive extraction of organoarsenicals.

Evolution of Lava Sheets for LIPs: Types of Local and Regional Trends

NASA Astrophysics Data System (ADS)

Rakhmenkulova, I. F.; Sharapov, V. N.

2011-12-01

The North-Atlantic Igneous Province (NAIP), the Permian-Triassic traps of the Siberian Platform (SP), and the volcanic shields of the Hawaiian Ridge can be regarded as the examples of local and regional trends for lava sheets evolution of LIPs. Complex statistical analysis for distribution functions of petrogenic and trace components showed that cyclicity and spatial asymmetry for melt compositions are typical for all lava sheets of LIPs. NAIP has the following features: 1) the formation of continental swell and its rifting; 2) the oceanic basin formation as a system of open basins at the east and the opening of the Central Atlantic to the north with the transverse volcanic zone of the Ferraro Ridge; 3) quick opening of the oceanic basin with the formation and accretion of lava sheet in the centre of the spreading zone (MOR). At the western NAIP part, during the sheet breakage, magnesian melts were forming, in the east - 'typical' trap tholeiitic association with thick lava profiles; oceanic part of the system contains various oceanic basalts. Iceland lava sheet passed through at least three subsequent formation stages with typical petrochemical igneous rock complexes. There are local petrochemical trends in the Iceland sheet: as the basalt crust thickens, acid melt amounts increase. The Permian-Triassic SP traps at the southern part of the Khatanga Rift (where the province started to develop spatially) have the following zones: layered profiles of tuffaceous rocks in the Tunguska Syncline, with various quantities of lava flows in the upper part of the profiles; to the south, within the holes between the net of fissure and central lava-breccia volcanic structures, reloaded tuff material is located; more to the south this structural zone changes to swarms of dyke-diatreme structures having typical near-vent depressions. The explosive coefficient within these zones increases from the north to the south. In the western part of trap zone there is a petrochemical zoning - in general basalts become less magnesian from the Norilsk mulde to the Angaro-Ilim iron-ore region, while intrusive rocks become more titanic and alkaline. In local time distribution functions of petrogenic and trace components various trends are recorded. The above-mentioned LIP characteristics for the Hawaiian volcanic ridge have the following specific features: 1) lava compositions and volumes change from the north to the south along the strike of the Hawaiian-Emperor Chain; 2) lava compositions in the southern part of the Hawaiian Ridge are asymmetric transversely; 3) magma compositions in local lava shields for Kea and Loa lines of the southern part of the Hawaiian Ridge are cyclic; 4) volcanogenic rocks of this area have some general properties: the compositions of petrogenic and trace components, as well as and the amounts of Pb and Hf isotopes increase in lavas from the south to the north; there are no spatial trends for Ti compounds and Sr isotopes; the amounts of Al, Fe, Mn, Na, K; P, C oxides, as well as the amounts of Sr, Eu, Tb, Rb, La, Th and Nd, Os isotopes decrease. We think that the recorded variation of LIP parameters is due to geodynamic conditions and the lithosphere rocks compositions.

A study of the impact of moist-heat and dry-heat treatment processes on hazardous trace elements migration in food waste.

PubMed

Chen, Ting; Jin, Yiying; Qiu, Xiaopeng; Chen, Xin

2015-03-01

Using laboratory experiments, the authors investigated the impact of dry-heat and moist-heat treatment processes on hazardous trace elements (As, Hg, Cd, Cr, and Pb) in food waste and explored their distribution patterns for three waste components: oil, aqueous, and solid components. The results indicated that an insignificant reduction of hazardous trace elements in heat-treated waste-0.61-14.29% after moist-heat treatment and 4.53-12.25% after dry-heat treatment-and a significant reduction in hazardous trace elements (except for Hg without external addition) after centrifugal dehydration (P < 0.5). Moreover, after heat treatment, over 90% of the hazardous trace elements in the waste were detected in the aqueous and solid components, whereas only a trace amount of hazardous trace elements was detected in the oil component (<0.01%). In addition, results indicated that heat treatment process did not significantly reduce the concentration of hazardous trace elements in food waste, but the separation process for solid and aqueous components, such as centrifugal dehydration, could reduce the risk considerably. Finally, combined with the separation technology for solid and liquid components, dry-heat treatment is superior to moist-heat treatment on the removal of external water-soluble ionic hazardous trace elements. An insignificant reduction of hazardous trace elements in heat-treated waste showed that heat treatment does not reduce trace elements contamination in food waste considerably, whereas the separation process for solid and aqueous components, such as centrifugal dehydration, could reduce the risk significantly. Moreover, combined with the separation technology for solid and liquid components, dry-heat treatment is superior to moist-heat treatment for the removal of external water-soluble ionic hazardous trace elements, by exploring distribution patterns of trace elements in three waste components: oil, aqueous, and solid components.

Undegassed Carbon Content from a Highly Depleted Segment of the Mid-Atlantic Ridge (1-5°S): Evidence from Melt Inclusions

NASA Astrophysics Data System (ADS)

Le Voyer, M.; Kelley, K. A.; Cottrell, E.; Hauri, E. H.

2014-12-01

As carbon solubility is low in basalts, MORB contain little dissolved CO2 (189±61 ppm, 1σ, n=600 [1]). A global negative correlation between CO2/Nb (proxy for amount of CO2 lost by degassing) and Ba/La (proxy for source enrichment) indicates that depleted MORB are less affected by degassing than enriched MORB: CO2/Nb ratios range from 0-100 for samples with Ba/La>4, while CO2/Nb range from 50 to 400 for samples with Ba/La<4 [1]. To assess the CO2 content of undegassed MORB, we analyzed the volatile content of 70 olivine-hosted, glassy melt inclusions (MIs) from four basalts dredged along MAR 1-5°S, a ridge segment that produces highly depleted MORB in terms of trace element enrichment and radiogenic isotopes [2, 3]. MIs contain CO2 contents (180-1420 ppm) that are higher than their respective matrix glasses (130-220 ppm, typical for vapor-saturated melts erupted at 3-5 km b.s.l.). One of the four dredges (EN061 5D-3Ag) contains MIs that do not exhibit shrinkage bubbles. For this sample only, we find a positive correlation between the CO2 content (240-770 ppm) and the Cl content (6-20 ppm) of the MIs that is not found in the matrix glasses (see Fig.). We infer that the correlation between CO2 and Cl, both highly incompatible in silicate minerals during fractional crystallization, is strong evidence for vapor-undersaturation, as any CO2 degassing would have erased the correlation. Together with MIs from the Siqueiros Fracture Zone [4] and from northern Iceland [5], the MIs from EN061 5D-3Ag may represent another occurrence of carbon-undersaturated MORB. Our results will be used to model the primary carbon content of MORB and of the depleted upper mantle. Note that the average Cl content of the matrix glasses (20±1 ppm) is higher than those of the MIs (12±3 ppm, see Fig.). This indicates either that the matrix glasses assimilated a small amount of seawater Cl, or that the MIs are all more depleted than the matrix glass. We will acquire major and trace element data in order to further investigate the origin of the low Cl and high CO2 contents in these MIs. Ref. [1] Le Voyer et al. 2014 Goldschmidt abstr. [2] Schilling et al. 1994 JGR 99 [3] Kelley et al. 2013 G3 [4] Saal et al. 2002 Nature 419 [5] Hauri and Saal 2009 EOS Fall suppl. AGU abstr.

Amplification of trace amounts of nucleic acids

DOEpatents

Church, George M [Brookline, MA; Zhang, Kun [Brighton, MA

2008-06-17

Methods of reducing background during amplification of small amounts of nucleic acids employ careful analysis of sources of low level contamination. Ultraviolet light can be used to reduce nucleic acid contaminants in reagents and equipment. "Primer-dimer" background can be reduced by judicious design of primers. We have shown clean signal-to-noise with as little as starting material as one single human cell (.about.6 picogram), E. coli cell (.about.5 femtogram) or Prochlorococcus cell (.about.3 femtogram).

Construction of uniformly sized pseudo template imprinted polymers coupled with HPLC-UV for the selective extraction and determination of trace estrogens in chicken tissue samples.

PubMed

Wang, Shu; Li, Yun; Wu, Xiaoli; Ding, Meijuan; Yuan, Lihua; Wang, Ruoyu; Wen, Tingting; Zhang, Jun; Chen, Lina; Zhou, Xuemin; Li, Fei

2011-02-28

To assess the potential risks associated with the environmental exposure of steroid estrogens, a novel highly efficient and selective estrogen enrichment procedure based on the use of molecularly imprinted polymer has been developed and evaluated. Herein, analogue of estrogens, namely 17-ethyl estradiol (EE(2)) was used as the pseudo template, to avoid the leakage of a trace amount of the target analytes. The resulting pseudo molecularly imprinted polymers (PMIPs) showed large sorption capacity, high recognition ability and fast binding kinetics for estrogens. Moreover, using these imprinted particles as dispersive solid-phase extraction (DSPE) materials, the amounts of three estrogens (E(1), E(2) and E(3)) which were detected by HPLC-UV from the chicken tissue samples were 0.28, 0.31 and 0.17 μg g(-1), and the recoveries were 72.5-78.7%, 90.3-95.2% and 80.5-83.6% in spiked chicken tissue samples with RSD <7%, respectively. All these results reveal that EE(2)-PMIPs as DSPE materials coupled with HPLC-UV could be applied to the highly selective separation and sensitive determination of trace estrogens in chicken tissue samples. Copyright © 2010 Elsevier B.V. All rights reserved.

Variable thickness double-refracting plate

DOEpatents

Hadeishi, Tetsuo

1976-01-01

This invention provides an A.C., cyclic, current-controlled, phase retardation plate that uses a magnetic clamp to produce stress birefringence. It was developed for an Isotope-Zeeman Atomic Absorption Spectrometer that uses polarization modulation to effect automatic background correction in atomic absorption trace-element measurements. To this end, the phase retardation plate of the invention is a variable thickness, photoelastic, double-refracting plate that is alternately stressed and released by the magnetic clamp selectively to modulate specific components selected from the group consisting of circularly and plane polarized Zeeman components that are produced in a dc magnetic field so that they correspond respectively to Zeeman reference and transmission-probe absorption components. The polarization modulation changes the phase of these polarized Zeeman components, designated as .sigma. reference and .pi. absorption components, so that every half cycle the components change from a transmission mode to a mode in which the .pi. component is blocked and the .sigma. components are transmitted. Thus, the Zeeman absorption component, which corresponds in amplitude to the amount of the trace element to be measured in a sample, is alternately transmitted and blocked by a linear polarizer, while the circularly polarized reference components are continuously transmitted thereby. The result is a sinusoidally varying output light amplitude whose average corresponds to the amount of the trace element present in the sample.

Preparation of modified magnetic nanoparticles as a sorbent for the preconcentration and determination of cadmium ions in food and environmental water samples prior to flame atomic absorption spectrometry

NASA Astrophysics Data System (ADS)

Mirabi, Ali; Dalirandeh, Zeinab; Rad, Ali Shokuhi

2015-05-01

A new method has been developed for the separation/preconcentration of trace level cadmium ions using diphenyl carbazone/sodium dodecyl sulfate immobilized on magnetic nanoparticle Fe3O4 as a new sorbent SPE and their determination by flame atomic absorption spectrometry (FAAS). Synthesized nanoparticle was characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM). Various influencing parameters on the separation and preconcentration of trace level cadmium ions such as, pH value, amount of nanoparticles, amount of diphenyl carbazone, condition of eluting solution, the effects of matrix ions were examined. The cadmium ions can be eluted from the modified magnetic nanoparticle using 1 mol L-1 HCl as a desorption reagent. The detection limit of this method for cadmium was 3.71 ng ml-1 and the R.S.D. was 0.503% (n=6). The advantages of this new method include rapidity, easy preparation of sorbents and a high concentration factor. The proposed method has been applied to the determination of Cd ions at trace levels in real samples such as, green tea, rice, tobacco, carrot, lettuce, ginseng, spice, tap water, river water, sea water with satisfactory results.

RELATIONSHIPS BETWEEN LABORATORY AND PILOT-SCALE COMBUSTION OF SOME CHLORINATED HYDROCARBONS

EPA Science Inventory

Factors governing the occurence of trace amounts of residual organic substance emmissions (ROSEs) in full-scale incierators are not fully understood. Pilot-scale spray combustion expereiments involving some liquid chlorinated hydrocarbons (CHCs) and their dilute mixtures with hy...

Determination of trace metals in spirits by total reflection X-ray fluorescence spectrometry

NASA Astrophysics Data System (ADS)

Siviero, G.; Cinosi, A.; Monticelli, D.; Seralessandri, L.

2018-06-01

Eight spirituous samples were analyzed for trace metal content with Horizon Total Reflection X-Ray Fluorescence (TXRF) Spectrometer. The expected single metal amount is at the ng/g level in a mixed aqueous/organic matrix, thus requiring a sample preparation method capable of achieving suitable limits of detection. On-site enrichment and Atmospheric Pressure-Vapor Phase Decomposition allowed to detect Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Sr and Pb with detection limits ranging from 0.1 ng/g to 4.6 ng/g. These results highlight how the synergy between instrument and sample preparation strategy may foster the use of TXRF as a fast and reliable technique for the determination of trace elements in spirituous samples, either for quality control or risk assessment purposes.

Collaborative Study of Analysis of High Resolution Infrared Atmospheric Spectra Between NASA Langley Research Center and the University of Denver

NASA Technical Reports Server (NTRS)

Goldman, Aaron

1999-01-01

The Langley-D.U. collaboration on the analysis of high resolution infrared atmospheric spectra covered a number of important studies of trace gases identification and quantification from field spectra, and spectral line parameters analysis. The collaborative work included: Quantification and monitoring of trace gases from ground-based spectra available from various locations and seasons and from balloon flights. Studies toward identification and quantification of isotopic species, mostly oxygen and Sulfur isotopes. Search for new species on the available spectra. Update of spectroscopic line parameters, by combining laboratory and atmospheric spectra with theoretical spectroscopy methods. Study of trends of atmosphere trace constituents. Algorithms developments, retrievals intercomparisons and automatization of the analysis of NDSC spectra, for both column amounts and vertical profiles.

Determination of trace metals in drinking water in Irbid City-Northern Jordan.

PubMed

Alomary, Ahmed

2013-02-01

Drinking water samples from Irbid, the second populated city in Jordan were analyzed for trace metals (As, Ba, Cd, Pb, Cr, Cu, Fe, Zn, Mn, Ni, and Se) content. The study was undertaken to determine if the metal concentrations were within the national and international guidelines. A total of 90 drinking water samples were collected from Al-Yarmouk University area. The samples were collected from three different water types: tap water (TW), home-purified water (HPW), and plant-purified water (PPW). All the samples were analyzed for trace metals using an inductively coupled plasma-optical emission spectrometry. All the samples analyzed were within the United States Environmental Protection Agency admissible pH limit (6.5-8.5). The results showed that concentrations of the trace metals vary significantly between the three drinking water types. The results showed that HPW samples have the lowest level of trace metals and the concentrations of some essential trace metals in these samples are less than the recommended amounts. Slight differences in the metal contents were found between HPW samples, little differences between PPW samples; however, significant differences were found between TW samples. Although some TW samples showed high levels of trace metals, however, the mean level of most elements determined in the samples were well within the Jordanian standards as well as the World Health Organization standards for drinking water.

Constructing Space-Time Views from Fixed Size Statistical Data: Getting the Best of both Worlds

NASA Technical Reports Server (NTRS)

Schmidt, Melisa; Yan, Jerry C.

1997-01-01

Many performance monitoring tools are currently available to the super-computing community. The performance data gathered and analyzed by these tools fall under two categories: statistics and event traces. Statistical data is much more compact but lacks the probative power event traces offer. Event traces, on the other hand, can easily fill up the entire file system during execution such that the instrumented execution may have to be terminated half way through. In this paper, we propose an innovative methodology for performance data gathering and representation that offers a middle ground. The user can trade-off tracing overhead, trace data size vs. data quality incrementally. In other words, the user will be able to limit the amount of trace collected and, at the same time, carry out some of the analysis event traces offer using space-time views for the entire execution. Two basic ideas arc employed: the use of averages to replace recording data for each instance and formulae to represent sequences associated with communication and control flow. With the help of a few simple examples, we illustrate the use of these techniques in performance tuning and compare the quality of the traces we collected vs. event traces. We found that the trace files thus obtained are, in deed, small, bounded and predictable before program execution and that the quality of the space time views generated from these statistical data are excellent. Furthermore, experimental results showed that the formulae proposed were able to capture 100% of all the sequences associated with 11 of the 15 applications tested. The performance of the formulae can be incrementally improved by allocating more memory at run-time to learn longer sequences.

Constructing Space-Time Views from Fixed Size Statistical Data: Getting the Best of Both Worlds

NASA Technical Reports Server (NTRS)

Schmidt, Melisa; Yan, Jerry C.; Bailey, David (Technical Monitor)

1996-01-01

Many performance monitoring tools are currently available to the super-computing community. The performance data gathered and analyzed by these tools fall under two categories: statistics and event traces. Statistical data is much more compact but lacks the probative power event traces offer. Event traces, on the other hand, can easily fill up the entire file system during execution such that the instrumented execution may have to be terminated half way through. In this paper, we propose an innovative methodology for performance data gathering and representation that offers a middle ground. The user can trade-off tracing overhead, trace data size vs. data quality incrementally. In other words, the user will be able to limit the amount of trace collected and, at the same time, carry out some of the analysis event traces offer using spacetime views for the entire execution. Two basic ideas are employed: the use of averages to replace recording data for each instance and "formulae" to represent sequences associated with communication and control flow. With the help of a few simple examples, we illustrate the use of these techniques in performance tuning and compare the quality of the traces we collected vs. event traces. We found that the trace files thus obtained are, in deed, small, bounded and predictable before program execution and that the quality of the space time views generated from these statistical data are excellent. Furthermore, experimental results showed that the formulae proposed were able to capture 100% of all the sequences associated with 11 of the 15 applications tested. The performance of the formulae can be incrementally improved by allocating more memory at run-time to learn longer sequences.

Quasi ?non-destructive? laser ablation-inductively coupled plasma-mass spectrometry fingerprinting of sapphires

NASA Astrophysics Data System (ADS)

Guillong, M.; Günther, D.

2001-07-01

A homogenized 193 nm excimer laser with a flat-top beam profile was used to study the capabilities of LA-ICP-MS for 'quasi' non-destructive fingerprinting and sourcing of sapphires from different locations. Sapphires contain 97-99% of Al 2O 3 (corundum), with the remainder composed of several trace elements, which can be used to distinguish the origin of these gemstones. The ablation behavior of sapphires, as well as the minimum quantity of sample removal that is required to determine these trace elements, was investigated. The optimum ablation conditions were a fluency of 6 J cm -2, a crater diameter of 120 μm, and a laser repetition rate of 10 Hz. The optimum time for the ablation was determined to be 2 s, equivalent to 20 laser pulses. The mean sample removal was 60 nm per pulse (approx. 3 ng per pulse). This allowed satisfactory trace element determination, and was found to cause the minimum amount of damage, while allowing for the fingerprinting of sapphires. More than 40 isotopes were measured using different spatial resolutions (20-120 μm) and eight elements were reproducibly detected in 25 sapphire samples from five different locations. The reproducibility of the trace element distribution is limited by the heterogeneity of the sample. The mean of five or more replicate analyses per sample was used. Calibration was carried out using NIST 612 glass reference material as external standard. The linear dynamic range of the ICP-MS (nine orders of magnitude) allowed the use of Al, the major element in sapphire, as an internal standard. The limits of detection for most of the light elements were in the μg g -1 range and were better for heavier elements (mass >85), being in the 0.1 μg g -1 range. The accuracy of the determinations was demonstrated by comparison with XRF analyses of the same set of samples. Using the quantitative analyses obtained using LA-ICP-MS, natural sapphires from five different origins were statistically classified using ternary plots and principal multi-component analysis.

Heavy metals and manganese oxides in the genesee watershed, New York state: effects of geology and land use

USGS Publications Warehouse

Whitney, P.R.

1981-01-01

Manganese oxide coatings on gravels from 255 sites on tributary streams in the Genesee River Watershed were analyzed for Mn, Fe, Zn, Cd, Co, Ni, Pb, and Cu. The results were compared with data on bedrock geology, surficial geology and land use, using factor analysis and stepwise multiple regression. All metals except Pb show strong positive correlation with Mn. This association results from the well-known tendency of Mn oxide precipitates to adsorb and incorporate dissolved trace metals. Pb may be present in a separate phase on the gravel surfaces; alternatively Pb abundance may be so strongly influenced by environmental factors that the effect of varying abundance of the carrier phase becomes relatively unimportant. When the effects of varying Mn abundance are allowed for, Pb and to a lesser extent Zn and Cu abundances are seen to be related to commercial, industrial and residential land use. In addition to this pollution effect, all the trace metals, Cd and Ni most strongly, tend to be more abundant in oxide coatings from streams in the forested uplands in the southern part of the area. This probably reflects increased geochemical mobility of the metals in the more acid soils and groundwater of the southern region. A strong Zn anomaly is present in streams draining areas underlain by the Lockport Formation. Oxide coatings in these streams contain up to 5% Zn, originating from disseminated sphalerite in the Lockport and secondary Zn concentrations in the overlying muck soils. The same group of metals, plus calcium and loss on ignition, were determined in the silt and clay (minus 230 mesh) fraction of stream sediments from 129 of the same sites, using a hot nitric acid leach. The amounts of manganese in the sediments are low (average 1020 ppm) and manganese oxides are, at most, of relatively minor significance in the trace-metal geochemistry of these sediments. The bulk of the trace metals in sediment appears to be associated with iron oxides, clays and organic matter. ?? 1981.

Concentration of trace elements on branded cigarette in Malaysia

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

Azman, Muhammad Azfar, E-mail: m-azfar@nuclearmalaysia.gov.my; Hamzah, Suhaimi; Rahman, Shamsiah Abdul

Tobacco is a plant that is used as a recreational drug since the beginning of its use by the Native Americans. Now with the development of the tobacco industry, smoking has become a norm for the public in Malaysia. Trace elements in plants are mostly due to the uptake processes from the soils into the roots of the plants. The concentration of the elements may also be influenced by the elements contained in the water and also fertilizers. This paper aim to analyze the concentration of the trace elements contained in the branded cigarettes sold in Malaysia by utilizing themore » neutron activation analysis. The tobaccos were taken out from the cigarettes. The collected samples were air dried and passed through 2 mm sieve. Instrumental Neutron Activation Analysis (NAA) has been used for the determination of trace elements. Samples were activated in the Nuclear Malaysia Triga Mark II reactor with a neutron flux of 2.0 x 10{sup 12} n cm{sup -2} s{sup -1}. The samples then were analyzed using ORTEC Gamma Spectrometer a co-axial n-type HPGe detector with resolution of 2.0 keV at 1332 keV and relative efficiency of 20%. The data obtained could help in assessing the concentration of the trace elements that complying with the standard limitation dose proposed by World Health Organization (WHO)« less

Paper-based SERS swab for rapid trace detection on real-world surfaces.

PubMed

Lee, Chang H; Tian, Limei; Singamaneni, Srikanth

2010-12-01

One of the important but often overlooked considerations in the design of surface-enhanced Raman scattering (SERS) substrates for trace detection is the efficiency of sample collection. Conventional designs based on rigid substrates such as silicon, alumina, and glass resist conformal contact with the surface under investigation, making the sample collection inefficient. We demonstrate a novel SERS substrate based on common filter paper adsorbed with gold nanorods, which allows conformal contact with real-world surfaces, thus dramatically enhancing the sample collection efficiency compared to conventional rigid substrates. We demonstrate the detection of trace amounts of analyte (140 pg spread over 4 cm2) by simply swabbing the surface under investigation with the novel SERS substrate. The hierarchical fibrous structure of paper serves as a 3D vasculature for easy uptake and transport of the analytes to the electromagnetic hot spots in the paper. Simple yet highly efficient and cost-effective SERS substrate demonstrated here brings SERS-based trace detection closer to real-world applications.

Atmosphere-Ocean Coupling through Trace Gases

NASA Astrophysics Data System (ADS)

Tegtmeier, S.; Atlas, E. L.; Krüger, K.; Lennartz, S. T.; Marandino, C. A.; Patra, P. K.; Quack, B.; Schlundt, C.

2017-12-01

Halogen- and sulfur-containing trace gases, as well as other volatile organic compounds (VOCs, such as isoprene) from biogeochemical marine sources are important constituents of the ocean and the atmosphere. These compounds exert wide-ranging influence on atmospheric chemical processes and climate interactions, as well as on human health in coastal regions. In their reactive form, they can affect the oxidizing capacity of the air and lead to the formation of new particles or the growth of existing ones. In this contribution, marine derived halogen-, sulfur-, and oxygen-containing compounds will be discussed. Their net flux into the atmosphere and their impact on atmospheric processes is analyzed based on observations and model simulations.

Oxidation of a Silica-Containing Material in a Mach 0.3 Burner Rig

NASA Technical Reports Server (NTRS)

Nguyen, QuynhGiao N.; Cuy, Michael D.; Gray, Hugh R. (Technical Monitor)

2002-01-01

A primarily silica-containing material with traces of organic compounds, as well as aluminum and calcium additions, was exposed to a Mach 0.3 burner rig at atmospheric pressure using jet fuel. The sample was exposed for 5 continuous hours at 1370 C. Post exposure x-ray diffraction analyses indicate formation of cristobalite, quartz, NiO and Spinel (Al(Ni)CR2O4). The rig hardware is composed of a nickel-based superalloy with traces of Fe. These elements are indicated in the energy dispersive spectroscopy (EDS) results. This material was studied as a candidate for high temperature applications under an engine technology program.

Muscarinic receptors in amygdala control trace fear conditioning.

PubMed

Baysinger, Amber N; Kent, Brianne A; Brown, Thomas H

2012-01-01

Intelligent behavior requires transient memory, which entails the ability to retain information over short time periods. A newly-emerging hypothesis posits that endogenous persistent firing (EPF) is the neurophysiological foundation for aspects or types of transient memory. EPF is enabled by the activation of muscarinic acetylcholine receptors (mAChRs) and is triggered by suprathreshold stimulation. EPF occurs in several brain regions, including the lateral amygdala (LA). The present study examined the role of amygdalar mAChRs in trace fear conditioning, a paradigm that requires transient memory. If mAChR-dependent EPF selectively supports transient memory, then blocking amygdalar mAChRs should impair trace conditioning, while sparing delay and context conditioning, which presumably do not rely upon transient memory. To test the EPF hypothesis, LA was bilaterally infused, prior to trace or delay conditioning, with either a mAChR antagonist (scopolamine) or saline. Computerized video analysis quantified the amount of freezing elicited by the cue and by the training context. Scopolamine infusion profoundly reduced freezing in the trace conditioning group but had no significant effect on delay or context conditioning. This pattern of results was uniquely anticipated by the EPF hypothesis. The present findings are discussed in terms of a systems-level theory of how EPF in LA and several other brain regions might help support trace fear conditioning.

Trace elements and radionuclides in palm oil, soil, water, and leaves from oil palm plantations: A review.

PubMed

Olafisoye, O B; Oguntibeju, O O; Osibote, O A

2017-05-03

Oil palm (Elaeisguineensis) is one of the most productive oil producing plant in the world. Crude palm oil is composed of triglycerides supplying the world's need of edible oils and fats. Palm oil also provides essential elements and antioxidants that are potential mediators of cellular functions. Experimental studies have demonstrated the toxicity of the accumulation of significant amounts of nonessential trace elements and radionuclides in palm oil that affects the health of consumers. It has been reported that uptake of trace elements and radionuclides from the oil palm tree may be from water and soil on the palm plantations. In the present review, an attempt was made to revise and access knowledge on the presence of some selected trace elements and radionuclides in palm oil, soil, water, and leaves from oil palm plantations based on the available facts and data. Existing reports show that the presence of nonessential trace elements and radionuclides in palm oil may be from natural or anthropogenic sources in the environment. However, the available literature is limited and further research need to be channeled to the investigation of trace elements and radionuclides in soil, water, leaves, and palm oil from oil palm plantations around the globe.

Behavioral tracing demonstrates dietary nutrient discrimination in two-spotted crickets Gryllus bimaculatus.

PubMed

Fukumura, Keisuke; Nagata, Shinji

2017-10-01

Animals select appropriate diets to meet their nutritional requirements. Here, we demonstrate the availability for analysis of feeding preference using an orthopteran, the two-spotted cricket Gryllus bimaculatus. A time-course study of these insects, involving continuous recording and tracing behavior for 9 h, allowed us to monitor discrimination of diet that contained various nutrients.

Local Semantic Trace: A Method to Analyze Very Small and Unstructured Texts for Propositional Knowledge

ERIC Educational Resources Information Center

Pirnay-Dummer, Pablo

2015-01-01

A local semantic trace is a certain quasi-propositional structure that can still be reconstructed from written content that is incomplete or does not follow a proper grammar. It can also retrace bits of knowledge from text containing only very few words, making the microstructure of these artifacts of knowledge externalization available for…

NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE--COMPENDIUM OF METHODS FOR ANALYSIS OF TRACE METALS AND PESTICIDES IN DIETARY SAMPLES USING TOTAL DIET STUDY PROCEDURES (FDA-COMPENDIUM)

EPA Science Inventory

This compendium contains seven SOPs developed by Food and Drug Administration (FDA) laboratories for methods of analyzing trace metals in dietary samples collected using Total Diet study procedures. The SOPs include the following: (1) Quality Control for Analysis of NHEXAS Food o...

An algorithm to help design fire simulation and other data base work

Treesearch

Romain Mees

1974-01-01

The data necessary for fire simulation may be made available through an algorithm based on tracing of boundaries composed of straight-line segments. Useful assumptions are that if a closed boundary does not contain a given point, then any other closed boundary contained within the former one does not contain the location; and that a given location will be contained in...

Increased sensitivity of RT-PCR for Potato virus Y detection using RNA isolated by a procedure with differential centrifugation.

PubMed

Zhang, Jianhua; Nie, Xianzhou; Boquel, Sébastien; Al-Daoud, Fadi; Pelletier, Yvan

2015-12-01

The sensitivity of reverse transcription-polymerase chain reaction (RT-PCR) for virus detection is influenced by many factors such as specificity of primers and quality of templates. These factors become extremely important for successful detection when virus concentration is low. Total RNA isolated from Potato virus Y (PVY)-infected potato plants using the sodium sulfite RNA isolation method or RNeasy plant mini kit contains a high proportion of host RNA and may also contain trace amount of phenolic and polysaccharide residues, which may inhibit RT-PCR. The goal of this study was to enhance the sensitivity of PVY detection by reducing host RNA in the extract by differential centrifugation followed by extraction using an RNeasy mini kit (DCR method). One-step RT-PCR had relatively low amplification efficiency for PVY RNA when a high proportion of plant RNA was present. SYBR Green-based real time RT-PCR showed that the RNA isolated by the DCR method had a higher cycle threshold value (Ct) for the elongation factor 1-α mRNA (Ef1α) of potato than the Ct value of the RNA extracted using the RNeasy plant mini kit, indicating that the DCR method significantly reduced the proportion of potato RNA in the extract. The detectable amount of RNA extracted using the DCR method was <0.001ng when plant sap from 10 PVY-infected and PVY-free potato leaflets in a 1.5:100 fresh weight ratio was extracted, compared with 0.01 and 0.02ng of RNA using the RNeasy plant mini kit and sodium sulfite RNA isolation methods, respectively. Copyright © 2015. Published by Elsevier B.V.

PRODUCTION, MANAGEMENT AND THE ENVIRONMENT SYMPOSIUM: Measurement and mitigation of reactive nitrogen species from swine and poultry production.

PubMed

Powers, W; Capelari, M

2017-05-01

Reactive nitrogen (Nr) species include oxides of nitrogen [N; nitric oxide, nitrogen dioxide and nitrous oxide (NO)], anions (nitrate and nitrite), and amine derivatives [ammonia (NH), ammonium salts and urea]. Of the different Nr species, air emissions from swine and poultry facilities are predominantly NH followed by NO. Excreta emissions are NH, ammonium ions, and urea with trace amounts of nitrate and nitrite. Farm systems and practices that handle manure as a wet product without pH modification favor almost exclusive NH production. Systems and practices associated with dry manure handling and bedded systems emit more NH than NO. Results from a turkey grow-out study estimated that just under 1% of consumed N was emitted as NO from housing, compared with just under 11% emitted as NH. Despite generally less NO emissions from animal housing compared with crop field emissions, NO emissions from housing are often greater than estimated. Lagoon systems emit more NO than either slurry or deep pit swine systems. Deep pit swine buildings emit only one-third the NO that is emitted from deep bedded swine systems. Laying hen, broiler chicken, and turkey buildings emit over 4 times as much NO as swine housing, on a weight-adjusted basis. Critical control points for mitigation center on: 1) reducing the amount of N excreted and, therefore, excreted N available for loss to air or water during housing, manure storage, or following land application of manures; 2) capturing excreted N to prevent release of N-containing compounds to air, water, or soil resources; or 3) conversion or treatment of N-containing compounds to non-reactive N gas.

Respiratory exposures associated with silicon carbide production: estimation of cumulative exposures for an epidemiological study.

PubMed Central

Smith, T J; Hammond, S K; Laidlaw, F; Fine, S

1984-01-01

Silicon carbide is produced by heating a mixture of petroleum coke and silica sand to approximately 2000 degrees C in an electric furnace for 36 hours. During heating, large amounts of carbon monoxide are released, sulphur dioxide is produced from residual sulphur in the coke, and hydrocarbon fume is produced by pyrolysis of the coke. Loading and unloading furnaces causes exposures to respirable dust containing crystalline silica, silicon carbide, and hydrocarbons. In the autumn of 1980 extensive measurements were made of personal exposures to air contaminants. Eight hour time weighted exposures to sulphur dioxide ranged from less than 0.1 ppm to 1.5 ppm and respirable participate exposures ranged from 0.01 mg/m3 to 9.0 mg/m3. Geometric mean particulate exposures for jobs ranged from 0.1 mg/m3 to 1.46 mg/m3. The particulate contained varying amounts of alpha-quartz, ranging from less than 1% to 17%, and most quartz exposures were substantially below the threshold limit value of 100 micrograms/m3. Only traces of cristobalite (less than 1%) were found in the particulate. Median exposures to air contaminants in each job were estimated. Since the operations at the plant had been stable over the past 30 years, it was possible to estimate long term exposures of workers to sulphur dioxide, respirable particulate, quartz, total inorganic material, and extractable organic material. Cumulative exposure (average concentration times exposure duration) for each of the air contaminants was estimated for each worker using his job history. There was sufficient independent variability in the sulphur dioxide and respirable particulate cumulative exposures to make an assessment of their independent effects feasible. The theoretical basis for using the cumulative exposure index and its shortcomings for epidemiological applications were presented. PMID:6691927

Environmental impact assessment of radionuclides and trace elements at the Kurday U mining site, Kazakhstan.

PubMed

Salbu, B; Burkitbaev, M; Strømman, G; Shishkov, I; Kayukov, P; Uralbekov, B; Rosseland, B O

2013-09-01

The Kurday uranium mining site in Kazakhstan operated from 1954 to 1965 as part of the USSR nuclear weapon programme. To assess the environmental impact of radionuclides and trace elements associated with the Kurday mining site, field expeditions were performed in 2006. In addition to in situ gamma and (220)Rn dose rate measurements, sampling included at site fractionation of water as well as sampling of water, fish, sediment, soils and vegetation. The concentrations of U and associated trace metals were enriched in the Pit Lake and in the artesian water (U exceeding the WHO guideline value for drinking water), and decreased downstream from the mining area. Uranium, As, Mo and Ni were predominantly present as mobile low molecular mass species in waters, while a significant proportion of Cr, Mn and Fe were associated with colloids and particles. Due to oxidation of divalent iron in the artesian ground water upon contact with air, Fe served as scavenger for other elements, and peak concentrations of U-, Ra-isotopes, As and Mn were seen. Most radionuclides and trace elements were contained in minerals in soils and sediments, and good correlations were obtained between U and As, Cd, Mo and (226)Ra. Based on sequential extractions, a significant fraction of U, Pb and Cd could be considered mobile. Radioactive particles carrying significant amount of trace metals may represent a hazard during strong wind events. The transfer of radionuclides and metals from soils or sediments to water was in general low. The Kd levels varied with the element in question, ranging from 0.5 to 3 × 10(2) L/kg d.w. for (238)U being relatively mobile, 10(3) for (226)Ra, As, Cd, Ni, to 10(4) L/kg d.w. for Cu, Cr and Pb being rather inert The transfer of radionuclides and metals from soils to vegetation (TF) was low, while higher if the transfer to vegetation, especially underwater mosses, occurred via water (e.g., BCF 37 L/kg w.w. for (238)U and 3 × 10(3) L/kg w.w. for (226)Ra). The transfer of Cd, Pb and As from water to fish liver (BCF) was rather high, showing BCFs in the range of 10(2)-10(3) L/kg w.w., and may, if eaten, represent a health risk. Furthermore, the high Hg level in fish filet reaching 0.3 mg/kg w.w. muscle and the tendency of biomagnification call for dietary restrictions. Total gamma and Rn dose rate to man amounted to about 6 mSv/y, while the highest calculated dose rate for non-human species based on the ERICA Assessment Tool were obtained in aquatic plants, with calculated mean doses of 700 μGy/hr, mostly due to the U exposure. Overall, it is concluded that measures such as restricted access to the Pit Lake as well as dietary restrictions with respect to drinking water and intake of fish should be taken to reduce the environmental risk to man and biota. Copyright © 2012. Published by Elsevier Ltd.

A simplified soil extraction sequence to monitor the main and trace element speciation in soil after compost and mineral fertilizer additions upon the composition of wheat grains

NASA Astrophysics Data System (ADS)

Sager, Manfred; Erhart, Eva

2016-04-01

High quality biological waste treatment aims at producing compost in order to maintain a clean environment and to sustain soil organic carbon levels. Fertilization with compost as a source of organic carbon, nutrients, and accessory elements, as well as fertilization with mineral N- and PK fertilizer have been tested in a field experiment on a calcaric Fluvisol in the Danube wetlands, at 4 levels each. Yields of wheat were recorded, and grains and soils were sampled from each treatment, and analyzed for main and trace element composition. The corresponding soils were characterized by mobile phases, obtained by leaching with 0,16M acetic acid to cover exchangeables plus carbonates, and subsequently by 0,1M oxalate buffer pH 3 to dissolve the pedogenic oxides. Total amounts were obtained from digests with perchloric- nitric-hydrofluoric acid. For quasi-total amounts, aqua regia was replaced by pressure decomposition with KClO3 in dilute nitric acid. The proposed extraction sequence permits to analyze and interpret soil for main elements, trace elements, nutrients and anions simultaneously. Factor analyses of soil extracts obtained from dilute acetic acid revealed Ba-Be-Cd-Cu-Li-S (traces), Ca-Mg-Mn (main carbonates), Al-Fe-B, Y, and P-K (nutrients) as chemically feasible principal components. Subsequent soil extracts from oxalate contained Al-B-Co-K-Na-Pb-Si-V-S (maybe acid silicate weathering), Cr-Li-Ni-Sr-Ti (maybe basic silicate weathering), Be-Cu-Fe-P, Co-Mg-Mn-Zn (Mn-oxides) and Ba-Sc as principal components. Factor analyses of total element data distinguished the principal components Ce-La-Li-Sc-Y-P (rare earths), Al-Ca-Fe-K-Mg-Na-P (main elements), Cd-Co-Cr-Cu-Ni-Zn (trace elements), As-Pb (contaminants), Ba-Mn-Sr, and Ti, which looks chemically feasible also. Factor analyses of those soil fractions which presumably form the main fractions of exchangeables, carbonates, pedogenic oxides and silicates, showed no cross connections, except for P. Oxalate-soluble Fe together with P and S was independent from oxalate-soluble Al-Mn-Si. In the crops, all element levels were within a non-contaminated and non-deficient range, therefore correlations with concentrations as well as loads in the wheat grains where largely not pronounced. Maximum correlations between plant and soil data were obtained with Li and Be. The load data (concentration times yield, given in g/ha) were much more intercorrelated than the concentrations. Regarding the same element, correlation coefficients between loads and respective concentrations were larger than 0,800 for Al, Ba, Cd, Co, Cr, Li, Mo, Na, Ni, Se, and Sr, which means the transfer remained independent from the load. In case of Ca, Mg, P, S, Zn, however, correlation coefficients between loads and concentrations were < 0,500, thus the transfer was not constant because of obvious metabolic influences. The proposed method of soil characterization was applied at a field trial here for the first time, and offers new possibilities of intercorrelations between plant uptake and geochemical soil fractions.

ENVIRONMENTAL MANAGEMENT SCIENCE PROGRAM PROJECT NUMBER 87016 CO-PRECIPITATION OF TRACE METALS IN GROUNDWATER AND VADOSE ZONE CALCITE: IN SITU CONTAINMENT AND STABILIZATION OF STRONTIUM-90 AND OTHER DIVALENT METALS AND RADIONUCLIDES AT ARID WESTERN DOE SITES

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

Ferris, F. Grant; Fujita, Yoshiko; Smith, Robert W.

2004-06-15

Radionuclide and metal contaminants are present in the vadose zone and groundwater throughout the U.S. Department of Energy (DOE) weapons complex. In situ containment and stabilization of these contaminants in vadose zones or groundwater is a cost-effective treatment strategy. Our facilitated approach relies upon the hydrolysis of introduced urea to cause the acceleration of calcium carbonate precipitation (and trace metal coprecipitation) by increasing groundwater pH and alkalinity (Fujita et al., 2000; Warren et al., 2001). Subsurface urea hydrolysis is catalyzed by the urease enzyme, which may be either introduced with the urea or produced in situ by ubiquitous subsurface ureamore » hydrolyzing microorganisms. Because the precipitation processes are irreversible and many western aquifers are saturated with respect to calcite, the co-precipitated metals and radionuclides will be effectively removed from groundwater. The rate at which trace metals are incorporated into calcite is a function of calcite precipitation kinetics, adsorption interactions between the calcite surface and the trace metal in solution (Zachara et al., 1991), solid solution properties of the trace metal in calcite (Tesoriero and Pankow, 1996), and also the surfaces upon which the calcite is precipitating. A fundamental understanding of the coupling of calcite precipitation and trace metal partitioning, and how this occurs in aquifers and vadose environments is lacking. This report summarizes work undertaken during the second year of this project.« less

Coal Ash Aerosol in East Asian Outflow as a Source for Oceanic Deposition of Iron and Other Metals

NASA Astrophysics Data System (ADS)

Anderson, J. R.; Hua, X.

2008-12-01

While ocean deposition of East Asian dust is given significant emphasis as a source of biologically-active trace elements, iron in particular, dust events are episodic and highly seasonal. There is, however, a constant source of aerosol that is chemically similar to dust (albeit amorphous in structure rather than crystalline) in the ash particles emitted from many hundreds of coal-fired power plants that are sited along the entire coastal region of China and Korea. The emission controls on these facilities vary widely and, in even cases of state-of-the-art emission controls, the secondary release of ash can be significant. There are of course even more small industrial and household sources of coal combustion emissions, in most cases with little or no emissions controls. Ash from a modern coal-fired power facility in Korea has been examined chemically and morphologically with electron microscopic techniques. As is characteristic of all such facilities, two principal types of ash are present: (1) flyash, silicate glass spheres that are emitted with the smoke and removed by electrostatic precipitators; and (2) bottom ash, "clinkers" and noncombustible material sticking to the furnace walls that are mixed with water and ground after cooling, then removed as a slurry to a dumping area. In addition, iron sulfide (pyrite) is a common constituent of coal and provides both a source of sulfur dioxide gas and also molten iron spherical particles in the ash. The iron spheres then are rapidly oxidized upon cooling. Bottom ash is a more complex material than flyash in that it contains more iron and other trace metals, plus it contains varying amounts of uncombusted carbon. The post-combustion handling of bottom ash can lead to significant emissions despite the fact that little or none goes out the stack. The iron oxide spheres can also be emitted by this secondary method. The concentrations of ash can be very high in close proximity to power plants (PM10 of several hundred micrograms per cubic meter of air) and traces of these aerosols have been found in the ACE-Asia and PACDEX experiments above the Sea of Japan, the Yellow Sea and across the width of the North Pacific.

Differential-optoacoustic absorption detector

NASA Technical Reports Server (NTRS)

Shumate, M. S.

1977-01-01

Two-cell spectrophone detects trace amounts of atmospheric pollutants by measuring absorption coefficients of gases with various laser sources. Device measures pressure difference between two tapered cells with differential manometer. Background signal is reduced by balanced window heating and balanced carrier gas absorption in two cells.

Lead Speciation And Bioavailability In Apatite-Amended Sediments

EPA Science Inventory

The in situ sequestration of lead (Pb) in sediment with a phosphate amendment was investigated by Pb speciation and bioavailability. Sediment Pb in preamendment samples was identified as galena (PbS) with trace amounts of absorbed Pb. Sediment exposed to atmospheric conditions ...

Detection of Staphylococcal Enterotoxin in Food

PubMed Central

Casman, Ezra P.; Bennett, Reginald W.

1965-01-01

Methods are described for the extraction and serological detection of trace amounts of enterotoxins A and B in foods incriminated in outbreaks of staphylococcal food poisoning. Evidence is presented for the probable applicability of the methods for the detection of unidentified enterotoxins. PMID:14325876

Acrylamide in processed potato products

USDA-ARS?s Scientific Manuscript database

Trace amounts of acrylamide are found in many foods cooked at high temperatures. Acrylamide in processed potato products is formed from reducing sugars and asparagine and is a product of the Maillard reaction. Processed potato products including fries and chips are relatively high in acrylamide comp...

TraceContract

NASA Technical Reports Server (NTRS)

Kavelund, Klaus; Barringer, Howard

2012-01-01

TraceContract is an API (Application Programming Interface) for trace analysis. A trace is a sequence of events, and can, for example, be generated by a running program, instrumented appropriately to generate events. An event can be any data object. An example of a trace is a log file containing events that a programmer has found important to record during a program execution. Trace - Contract takes as input such a trace together with a specification formulated using the API and reports on any violations of the specification, potentially calling code (reactions) to be executed when violations are detected. The software is developed as an internal DSL (Domain Specific Language) in the Scala programming language. Scala is a relatively new programming language that is specifically convenient for defining such internal DSLs due to a number of language characteristics. This includes Scala s elegant combination of object-oriented and functional programming, a succinct notation, and an advanced type system. The DSL offers a combination of data-parameterized state machines and temporal logic, which is novel. As an extension of Scala, it is a very expressive and convenient log file analysis framework.

Organochlorine and heavy metal residues in bald eagle eggs

USGS Publications Warehouse

Krantz, W.C.; Mulhern, B.M.; Bagley, George E.; Sprunt, A.; Ligas, F.J.; Robertson, W.B.

1970-01-01

Bald eagle eggs collected in 1968 from nests in Wisconsin, Maine, and Florida all contained residues of DDE, DDD, dieldrin, heptachlor epoxide, and polychlorinated biphenyls. Many also contained traces of DDT. Eggs from five nonproductive nests sampled in Maine contained much higher residues than did eggs collected from either productive or nonproductive nests in Wisconsin and Florida.

Flame atomic absorption spectrometric determination of trace amounts of nickel after extraction and preconcentration onto natural modified analcime zeolite loaded with 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol.

PubMed

Afzali, Darush; Taher, Mohammad Ali; Mostafavi, Ali; Mahani, Mohammad Khayatzadeh

2005-01-01

Nickel is a moderately toxic element compared with other transition metals. However, inhalation of nickel and its compounds leads to serious problems, including cancer of the respiratory system and a skin disorder, nickel-eczema. Thus, attention has focused on the toxicity of nickel at low concentrations, and the development of reliable, analytical approaches for the determination of trace amounts of nickel is needed. This paper describes a simple, rapid, and sensitive flame atomic absorption spectrometric method for the determination of trace amounts of nickel in various samples after adsorption of its 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol complex on a modified Analcime column in the pH range of 7.5-10.5. The retained analyte on the Analcime is recovered with 5.0 mL 2 M nitric acid and determined by flame atomic absorption spectrometry. The detection limit is 20 ng/mL, and the calibration curve is linear for analyte concentrations in the range of 0.1-8 microg/mL final solution, with a correlation coefficient of 0.9993. Eight replicate determinations of nickel at 2 microg/mL in the final solution gave an absorbance of 0.1222, with a relative standard deviation (RSD) of +/-1.2%. The interference of a large number of anions and cations was studied, and the proposed method was used for the determination of nickel in various standard reference samples. The accuracy of the proposed method was evaluated by analyzing standard reference samples, and the results were satisfactory (recoveries of >96%; RSD of <3.5%).

Determination and stereochemistry of proteinogenic and non-proteinogenic amino acids in Saudi Arabian date fruits.

PubMed

Ali, Hatem Salama Mohamed; Alhaj, Omar Amin; Al-Khalifa, Abdulrahman Saleh; Brückner, Hans

2014-09-01

Whereas an abundance of literature is available on the occurrence of common proteinogenic amino acids (AAs) in edible fruits of the date palm (Phoenix dactylifera L.), recent reports on non-proteinogenic (non-coded) AAs and amino components are scarce. With emphasis on these components we have analyzed total hydrolysates of twelve cultivars of date fruits using automated ion-exchange chromatography, HPLC employing a fluorescent aminoquinolyl label, and GC-MS of total hydrolysates using the chiral stationary phases Chirasil(®)-L-Val and Lipodex(®) E. Besides common proteinogenic AAs, relatively large amounts of the following non-proteinogenic amino acids were detected: (2S,5R)-5-hydroxypipecolic acid (1.4-4.0 g/kg dry matter, DM), 1-aminocyclopropane-1-carboxylic acid (1.3-2.6 g/kg DM), γ-amino-n-butyric acid (0.5-1.2 g/kg DM), (2S,4R)-4-hydroxyproline (130-230 mg/kg DM), L-pipecolic acid (40-140 mg/kg DM), and 2-aminoethanol (40-160 mg/kg DM) as well as low or trace amounts (<70 mg/kg DM) of L-ornithine, 5-hydroxylysine, β-alanine, and in some samples (<20 mg/kg DM) of (S)-β-aminoisobutyric acid and (<10 mg/kg DM) L-allo-isoleucine. In one date fruit, traces of α-aminoadipic acid could be determined. Enantiomeric analysis of 6 M DCl/D2O hydrolysates of AAs using chiral capillary gas chromatography-mass spectrometry revealed the presence of very low amounts of D-Ala, D-Asp, D-Glu, D-Ser and D-Phe (1.2-0.4%, relative to the corresponding L-enantiomers), besides traces (0.2-1%) of other D-AAs. The possible relevance of non-proteinogenic amino acids in date fruits is briefly addressed.

[Proposal of new trace elements classification to be used in nutrition, oligotherapy and other therapeutics strategies].

PubMed

Ramírez Hernández, Javier; Bonete Pérez, María José; Martínez Espinosa, Rosa María

2014-12-17

1) to propose a new classification of the trace elements based on a study of the recently reported research; 2) to offer detailed and actualized information about trace elements. the analysis of the research results recently reported reveals that the advances of the molecular analysis techniques point out the importance of certain trace elements in human health. A detailed analysis of the catalytic function related to several elements not considered essential o probably essentials up to now is also offered. To perform the integral analysis of the enzymes containing trace elements informatics tools have been used. Actualized information about physiological role, kinetics, metabolism, dietetic sources and factors promoting trace elements scarcity or toxicity is also presented. Oligotherapy uses catalytic active trace elements with therapeutic proposals. The new trace element classification here presented will be of high interest for different professional sectors: doctors and other professions related to medicine; nutritionist, pharmaceutics, etc. Using this new classification and approaches, new therapeutic strategies could be designed to mitigate symptomatology related to several pathologies, particularly carential and metabolic diseases. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Standoff detection of trace amounts of solids by nonlinear Raman spectroscopy using shaped femtosecond pulses

NASA Astrophysics Data System (ADS)

Katz, O.; Natan, A.; Silberberg, Y.; Rosenwaks, S.

2008-04-01

We demonstrate a single-beam, standoff (>10m) detection and identification of various materials including minute amounts of explosives under ambient light conditions. This is obtained by multiplex coherent anti-Stokes Raman scattering spectroscopy (CARS) using a single femtosecond phase-shaped laser pulse. We exploit the strong nonresonant background for amplification of the backscattered resonant CARS signals by employing a homodyne detection scheme. The simple and highly sensitive spectroscopic technique has a potential for hazardous materials standoff detection applications.

Can Dynamic Bubble Templating Play a Role in Corrosion Product Morphology?

DTIC Science & Technology

2012-02-01

FeOOH (goethite) with moderate amounts of metallic luster Fe304 (magnetite), and trace amounts of CaC03 (calcite). In addition, the core was marbled ...cathodically produced gas bubbles (i.e., H2). By physically separating the anode and cathode. Stone and Goldstein26 generated tubular structures electro...D.A. Stone , RE. Goldstein. Proc. MatL Acad. Set U.S-A. 101 (2004): p. 11537. G. Butler, H.C.K. Ison, Nature 182 (1958): p. 1229. B. McEnaney. D.C

Effect of doping in the Bi-Sr-Ca-Cu-O superconductor

NASA Technical Reports Server (NTRS)

Akbar, S. A.; Wong, M. S.; Botelho, M. J.; Sung, Y. M.; Alauddin, M.; Drummer, C. E.; Fair, M. J.

1991-01-01

The results of the effect of doping on the superconducting transition in the Bi-Sr-Ca-Cu-O system are reported. Samples were prepared under identical conditions with varying types (Pb, Sb, Sn, Nb) and amounts of dopants. All samples consisted of multiple phases, and showed stable and reproducible superconducting transitions. Stabilization of the well known 110 K phase depends on both the type and amount of dopant. No trace of superconducting phase of 150 K and above was observed.

Trace elements in fish from Taihu Lake, China: levels, associated risks, and trophic transfer.

PubMed

Hao, Ying; Chen, Liang; Zhang, Xiaolan; Zhang, Dongping; Zhang, Xinyu; Yu, Yingxin; Fu, Jiamo

2013-04-01

Concentrations of eight trace elements [iron (Fe), manganese (Mn), zinc (Zn), chromium (Cr), mercury (Hg), cadmium (Cd), lead (Pb), and arsenic (As)] were measured in a total of 198 samples covering 24 fish species collected from Taihu Lake, China, in September 2009. The trace elements were detected in all samples, and the total mean concentrations ranged from 18.2 to 215.8 μg/g dw (dry weight). The concentrations of the trace elements followed the sequence of Zn>Fe>Mn>Cr>As>Hg>Pb>Cd. The measured trace element concentrations in fish from Taihu Lake were similar to or lower than the reported values in fish around the world. The metal pollution index was used to compare the total trace element accumulation levels among various species. Toxabramis swinhonis (1.606) accumulated the highest level of the total trace elements, and Saurogobio dabryi (0.315) contained the lowest. The concentrations of human non-essential trace elements (Hg, Cd, Pb, and As) were lower than the allowable maximum levels in fish in China and the European Union. The relationships between the trace element concentrations and the δ(15)N values of fish species were used to investigate the trophic transfer potential of the trace elements. Of the trace elements, Hg might be biomagnified through the food chain in Taihu Lake if the significant level of p-value was set at 0.1. No biomagnification and biodilution were observed for other trace elements. Copyright © 2012 Elsevier Inc. All rights reserved.

Radioactive mineral springs in Delta County, Colorado

USGS Publications Warehouse

Cadigan, Robert A.; Rosholt, John N.; Felmlee, J. Karen

1976-01-01

The system of springs in Delta County, Colo., contains geochemical clues to the nature and location of buried uranium-mineralized rock. The springs, which occur along the Gunnison River and a principal tributary between Delta and Paonia, are regarded as evidence of a still-functioning hydrothermal system. Associated with the springs are hydrogen sulfide and sulfur dioxide gas seeps, carbon dioxide gas-powered geysers, thick travertine deposits including radioactive travertine, and a flowing warm-water (41?C) radioactive well. Geochemical study of the springs is based on surface observations, on-site water-property measurements, and sampling of water, travertine, soft precipitates, and mud. The spring deposits are mostly carbonates, sulfates, sulfides, and chlorides that locally contain notable amounts of some elements, such as arsenic, barium, lithium, and radium. Samples from five localities have somewhat different trace element assemblages even though they are related to the same hydrothermal system. All the spring waters but one are dominated by sodium chloride or sodium bicarbonate. The exception is an acid sulfate water with a pH of 2.9, which contains high concentrations of aluminum and iron. Most of the detectable radioactivity is due to the presence of radium-226, a uranium daughter product, but at least one spring precipitate contains abundant radium-228, a thorium daughter product. The 5:1 ratio of radium-228 to radium-226 suggests the proximity of a vein-type deposit as a source for the radium. The proposed locus of a thorium-uranium mineral deposit is believed to lie in the vicinity of Paonia, Colo. Exact direction and depth are not determinable from data now available.

[The challenge of electronic cigarettes].

PubMed

Córdoba García, Rodrigo

2014-01-01

The electronic cigarette (e-cig) is a device with a conventional cigarette shape that releases a determined dose of nicotine vapour through an electronic heating process. The nicotine cartridges vary significantly in the amount of nicotine released, even within the same brand. Not all brands admit that they contain nicotine, but this is detected in the majority of units analysed. The e-cig usually contains a propellant, such as propylene glycol, which is a lung irritant. The short-term respiratory effect of the vapour of an e-cig is similar to that caused by the smoke of a cigarette, and is a cause of broncho-restriction. The majority of brands contain glycerine and at least one case of lipoid pneumonia has been detected due to this substance. Many brands contain traces of N-nitrosamines, heavy metals, and other products that are found in conventional cigarette smoke, but in a much higher proportion. There is currently no scientific evidence available that shows it is an effective device for quitting smoking, thus it should not be pro-actively recommended for this purpose, and may interfere with the use of demonstrated scientific evidence-based treatments for quitting smoking. It may have an undesirable effect on promoting the starting of smoking in adolescents or keeping adult smokers consuming nicotine and on gestural dependency. The toxicity of the vapour is not well known, but it is known that they are not innocuous, thus they should not be used in closed public spaces. Copyright © 2014 Elsevier España, S.L. All rights reserved.

Evaluation of a new electronic preoperative reference marker for toric intraocular lens implantation by two different methods of analysis: Adobe Photoshop versus iTrace

PubMed Central

Farooqui, Javed Hussain; Sharma, Mansi; Koul, Archana; Dutta, Ranjan; Shroff, Noshir Minoo

2017-01-01

PURPOSE: The aim of this study is to compare two different methods of analysis of preoperative reference marking for toric intraocular lens (IOL) after marking with an electronic marker. SETTING/VENUE: Cataract and IOL Implantation Service, Shroff Eye Centre, New Delhi, India. PATIENTS AND METHODS: Fifty-two eyes of thirty patients planned for toric IOL implantation were included in the study. All patients had preoperative marking performed with an electronic preoperative two-step toric IOL reference marker (ASICO AE-2929). Reference marks were placed at 3-and 9-o'clock positions. Marks were analyzed with two systems. First, slit-lamp photographs taken and analyzed using Adobe Photoshop (version 7.0). Second, Tracey iTrace Visual Function Analyzer (version 5.1.1) was used for capturing corneal topograph examination and position of marks noted. Amount of alignment error was calculated. RESULTS: Mean absolute rotation error was 2.38 ± 1.78° by Photoshop and 2.87 ± 2.03° by iTrace which was not statistically significant (P = 0.215). Nearly 72.7% of eyes by Photoshop and 61.4% by iTrace had rotation error ≤3° (P = 0.359); and 90.9% of eyes by Photoshop and 81.8% by iTrace had rotation error ≤5° (P = 0.344). No significant difference in absolute amount of rotation between eyes when analyzed by either method. CONCLUSIONS: Difference in reference mark positions when analyzed by two systems suggests the presence of varying cyclotorsion at different points of time. Both analysis methods showed an approximately 3° of alignment error, which could contribute to 10% loss of astigmatic correction of toric IOL. This can be further compounded by intra-operative marking errors and final placement of IOL in the bag. PMID:28757694

Glow discharge detector

DOEpatents

Koo, Jackson C.; Yu, Conrad M.

2002-01-01

A highly sensitive electronic ion cell for the measurement of trace elements in He carrier gas which involves glow discharge. A constant wave (CW) glow discharge detector which is controlled through a biased resistor, can detect the change of electron density caused by impurities in the He carrier gas by many orders of magnitude larger than that caused by direct ionization or electron capture. The glow discharge detector utilizes a floating pseudo-electrode to form a probe in or near the plasma. By using this probe, the large variation of electron density due to trace amounts of impurities can be directly measured.

Extraction of CO2 from air samples for isotopic analysis and limits to ultra high precision delta18O determination in CO2 gas.

PubMed

Werner, R A; Rothe, M; Brand, W A

2001-01-01

The determination of delta18O values in CO2 at a precision level of +/-0.02 per thousand (delta-notation) has always been a challenging, if not impossible, analytical task. Here, we demonstrate that beyond the usually assumed major cause of uncertainty - water contamination - there are other, hitherto underestimated sources of contamination and processes which can alter the oxygen isotope composition of CO2. Active surfaces in the preparation line with which CO2 comes into contact, as well as traces of air in the sample, can alter the apparent delta18O value both temporarily and permanently. We investigated the effects of different surface materials including electropolished stainless steel, Duran glass, gold and quartz, the latter both untreated and silanized. CO2 frozen with liquid nitrogen showed a transient alteration of the 18O/16O ratio on all surfaces tested. The time to recover from the alteration as well as the size of the alteration varied with surface type. Quartz that had been ultrasonically cleaned for several hours with high purity water (0.05 microS) exhibited the smallest effect on the measured oxygen isotopic composition of CO2 before and after freezing. However, quartz proved to be mechanically unstable with time when subjected to repeated large temperature changes during operation. After several days of operation the gas released from the freezing step contained progressively increasing trace amounts of O2 probably originating from inclusions within the quartz, which precludes the use of quartz for cryogenically trapping CO2. Stainless steel or gold proved to be suitable materials after proper pre-treatment. To ensure a high trapping efficiency of CO2 from a flow of gas, a cold trap design was chosen comprising a thin wall 1/4" outer tube and a 1/8" inner tube, made respectively from electropolished stainless steel and gold. Due to a considerable 18O specific isotope effect during the release of CO2 from the cold surface, the thawing time had to be as long as 20 min for high precision delta18O measurements. The presence of traces of air in almost all CO2 gases that we analyzed was another major source of error. Nitrogen and oxygen in the ion source of our mass spectrometer (MAT 252, Finnigan MAT, Bremen, Germany) give rise to the production of NO2 at the hot tungsten filament. NO2+ is isobaric with C16O18O+ (m/z 46) and interferes with the delta18O measurement. Trace amounts of air are present in CO2 extracted cryogenically from air at -196 degrees C. This air, trapped at the cold surface, cannot be pumped away quantitatively. The amount of air present depends on the surface structure and, hence, the alteration of the measured delta18O value varies with the surface conditions. For automated high precision measurement of the isotopic composition of CO2 of air samples stored in glass flasks an extraction interface ('BGC-AirTrap') was developed which allows 18 analyses (including standards) per day to be made. For our reference CO2-in-air, stored in high pressure cylinders, the long term (>9 months) single sample precision was 0.012 per thousand for delta13C and 0.019 per thousand for delta18O. Copyright 2001 John Wiley & Sons, Ltd.

The Bacteriohopanepolyol Inventory of Novel Aerobic Methane Oxidising Bacteria Reveals New Biomarker Signatures of Aerobic Methanotrophy in Marine Systems

PubMed Central

Birgel, Daniel; Kappler, Andreas; Hirayama, Hisako; Peckmann, Jörn; Poulton, Simon W.; Nickel, Julia C.; Mangelsdorf, Kai; Kalyuzhnaya, Marina; Sidgwick, Frances R.; Talbot, Helen M.

2016-01-01

Aerobic methane oxidation (AMO) is one of the primary biologic pathways regulating the amount of methane (CH4) released into the environment. AMO acts as a sink of CH4, converting it into carbon dioxide before it reaches the atmosphere. It is of interest for (paleo)climate and carbon cycling studies to identify lipid biomarkers that can be used to trace AMO events, especially at times when the role of methane in the carbon cycle was more pronounced than today. AMO bacteria are known to synthesise bacteriohopanepolyol (BHP) lipids. Preliminary evidence pointed towards 35-aminobacteriohopane-30,31,32,33,34-pentol (aminopentol) being a characteristic biomarker for Type I methanotrophs. Here, the BHP compositions were examined for species of the recently described novel Type I methanotroph bacterial genera Methylomarinum and Methylomarinovum, as well as for a novel species of a Type I Methylomicrobium. Aminopentol was the most abundant BHP only in Methylomarinovum caldicuralii, while Methylomicrobium did not produce aminopentol at all. In addition to the expected regular aminotriol and aminotetrol BHPs, novel structures tentatively identified as methylcarbamate lipids related to C-35 amino-BHPs (MC-BHPs) were found to be synthesised in significant amounts by some AMO cultures. Subsequently, sediments and authigenic carbonates from methane-influenced marine environments were analysed. Most samples also did not contain significant amounts of aminopentol, indicating that aminopentol is not a useful biomarker for marine aerobic methanotophic bacteria. However, the BHP composition of the marine samples do point toward the novel MC-BHPs components being potential new biomarkers for AMO. PMID:27824887

The dissolution kinetics of industrial brine sludge wastes from a chlor-alkali industry as a sorbent for wet flue gas desulfurization (FGD).

PubMed

Masilela, E; Lerotholi, L; Seodigeng, T; Rutto, H

2018-02-01

The disposal of industrial brine sludge waste (IBSW) in chlor-alkali plants can be avoided by utilization of IBSW as a sorbent in wet flue gas desulfurization (FGD). The shrinking core model was used to determine the dissolution kinetics of IBSW, which is a vital step in wet FGD. The effects of solid-to-liquid ratio (m/v), temperature, pH, particle size, and stirring speed on the conversion and dissolution rate constant are determined. The conversion and dissolution rate constant decreases as the pH, particle size, and solid-to-liquid ratio are increased and increases as the temperature, concentration of acid, and stirring speed are increased. The sorbents before and after dissolution were characterized using x-ray fluorescence (XRF), x-ray diffraction (XRD), and scanning electron microscopy (SEM). An activation energy of 7.195 kJ/mol was obtained and the product layer diffusion model was found to be the rate-controlling step. The use of industrial brine sludge waste as an alternative sorbent in wet flue gas desulfurization can reduce the amounts of industrial wastes disposed of in landfills. This study has proved that the sorbent can contain up to 91% calcium carbonate and trace amounts of sulfate, magnesium, and so on. This can be used as new sorbent to reduce the amount of sulfur dioxide in the atmosphere and the by-product gypsum can be used in construction, as a plaster ingredient, as a fertilizer, and for soil conditioning. Therefore, the sorbent has both economic and environmental benefits.

Paenalcaligenes hermetiae sp. nov., isolated from the larval gut of Hermetia illucens (Diptera: Stratiomyidae), and emended description of the genus Paenalcaligenes.

PubMed

Lee, Youn Yeop; Lee, Jae Kook; Park, Kwan Ho; Kim, Seo-Yeon; Roh, Seong Woon; Lee, Sang-Beom; Choi, Youngcheol; Lee, Sung-Jae

2013-11-01

A novel Gram-stain-negative, facultatively anaerobic, non-motile and short rod-shaped bacterium, strain KBL009(T), was isolated from the larval gut of Hermetia illucens. Strain KBL009(T) grew optimally at 37 °C, at pH 6.0 and with 1-2 % (w/v) NaCl. The 16S rRNA gene sequence of strain KBL009(T) showed 97.6 % similarity to that of Paenalcaligenes hominis CCUG 53761A(T) indicating its classification with the genus Paenalcaligenes. The major fatty acids were cyclo-C17 : 0, C16 : 0 and summed feature 2 (comprising C14 : 0 3-OH/iso-C16 : 1). The respiratory quinones were ubiquinone-8 (Q-8), predominating, and a minor amount of Q-7. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, one unknown aminolipid and five unknown polar lipids. The polyamine pattern contained predominantly putrescine and relatively high amounts of spermidine. The betaproteobacterial-specific 2-hydroxyputrescine could only be detected in trace amounts. The G+C content of genomic DNA was 56.1 mol%. Results from DNA-DNA hybridization with P. hominis KCTC 23583(T) unambiguously demonstrated that strain KBL009(T) represents a novel species in the genus Paenalcaligenes. Based on phenotypic, genotypic and phylogenetic characterization, the novel species Paenalcaligenes hermetiae sp. nov. is proposed. The type strain is KBL009(T) ( = KACC 16840(T) = JCM 18423(T)). An emended description of the genus Paenalcaligenes is also provided.

Progress report of southeastern monazite exploration, 1952

USGS Publications Warehouse

Overstreet, W.C.; Theobald, P.K.; White, A.M.; Cuppels, N.P.; Caldwell, D.W.; Whitlow, J.W.

1953-01-01

Reconnaissance of placer monazite during the field season of 1952 covered 6,600 square miles drained by streams in the western Piedmont of Virginia 5 North Carolina, South Carolina,, and Georgia. Emphasis during this investigation was placed on the area between the Savannah River at the border of South Carolina and Georgia and the Catawba River in North Carolina because it contains most of the placers formerly mined for monaziteo Four other areas along the strike of the monazite-bearing crystalline rocks were also studied, They center around Mt. Airy, N.C., Athens, Ga. Griffin, Ga. and LaGrange, Ga. In the Savannah River Catawba River district, studies indicate that even the highest grade stream deposits of more than 10 million cubic yards of alluvium contain less than 1 pound of monazite per cubic yard. The average grade of the better deposits is about 0 0 5 pound of monazite per cubic yard. Only trace amounts of niobium, tantalum, and tin have been detected in the placers. Tungsten is absent. Locally gold adds a few cents per cubic yard to the value of placer ground. The best deposits range in size from 1 to 5 million cubic yards and contain 1 to 2 pounds of monazite to the cubic yard. Hundreds of placers smaller than 1 million cubic yards exceed 2 pounds of monazite to the cubic yard and locally attain an average of 10 pounds Monazite deposits around Athens, Ga., are similar to the smaller deposits in the central part of the Savannah River - Catawba River district. A few small very low-grade monazite placers were found near Mt. Airy, N.C., Griffin, Ga., and LaGrange Ga., but they are of no economic value. The larger the flood plain and the farther it lies from the source of the stream, the lower is the monazite content of the sediment. Monazite cannot be profitably mined .from the crystalline rocks in the five areas. The alluvial placers are in stream sediments of post-Wisconsin age. Some pre-Wisconsin terrace gravel of small areal extent is exposed but it contains only a small amount of monazite Pre-Wisconsin to early post-Wisconsin colluvial sediments locally contain 2 pounds of monazite to the cubic yard. Mode of presentation of reports covering field work during the seasons of 1951 - 52 is given. No further reconnaissance will be undertaken, in the western monazite belt.

Destruction of Navy Hazardous Wastes by Supercritical Water Oxidation

DTIC Science & Technology

1994-08-01

cleaning and derusting (nitrite and citric acid solutions), electroplating ( acids and metal bearing solutions), electronics and refrigeration... acid forming chemical species or that contain a large amount of dissolved solids present a challenge to current SCWO •-chnology. Approved for public...Waste streams that contain a large amount of mineral- acid forming chemical species or that contain a large amount of dissolved solids present a challenge

Convection of tin in a Bridgman system. I - Flow characterization by effective diffusivity measurements

NASA Technical Reports Server (NTRS)

Sears, B.; Narayanan, R.; Anderson, T. J.; Fripp, A. L.

1992-01-01

An electrochemical titration method was used to investigate the dynamic states in a cylindrical layer of convecting tin. The liquid tin was contained in a cell, with curved boundaries made of quartz and flat boundaries made of a solid state electrolyte - yttria-stabilized zirconia (YSZ). The electrolyte acted as a window through which a trace amount of oxygen could be pumped in or out by the application of a constant voltage. The concentration at the YSZ interface was monitored by operating the electrochemical cell in the galvanic mode. Experimentally determined effective diffusivities of oxygen were compared with the molecular diffusivity. Dynamic states in the convective flow were thus inferred. Temperature measurements were simultaneously made in order to identify the onset of oscillations from a steady convective regime. The experiments were conducted for two different aspect ratios for various imposed temperature gradients and two different orientations with respect to gravity. Transcritical states were identified and comparison to two-dimensional numerical models were made.

Issues of natural radioactivity in phosphates

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

Schnug, E.; Haneklaus, S.; Schnier, C.

1996-12-31

The fertilization of phosphorus (P) fertilizers is essential in agricultural production, but phosphates contain in dependence on their origin different amounts of trace elements. The problem of cadmium (Cd) loads and other heavy metals is well known. However, only a limited number of investigations examined the contamination of phosphates with the two heaviest metals, uranium (U) and thorium (Th), which are radioactive. Also potassium (K) is lightly radioactive. Measurements are done n the radioactivity content of phosphates, P fertilizers and soils. The radiation doses to workers and public as well as possible contamination of soils from phosphate rock or fertilizermore » caused by these elements or their daughter products is of interest with regard to radiation protection. The use of P fertilizers is necessary for a sustainable agriculture, but it involves radioactive contamination of soils. The consequences of the use of P fertilizers is discussed, also with regard to existing and proposed legislation. 11 refs., 2 figs., 7 tabs.« less

Comprehensive gas chromatography coupled to mass spectrometry for the separation of pesticides in a very complex matrix.

PubMed

Mondello, Luigi; Casilli, Alessandro; Tranchida, Peter Quinto; Lo Presti, Maria; Dugo, Paola; Dugo, Giovanni

2007-11-01

The present research is focused on the development of a comprehensive two-dimensional gas chromatography-rapid scanning quadrupole mass spectrometric (GC x GC-qMS) methodology for the analysis of trace-amount pesticides contained in a complex real-world sample. Reliable peak assignment was carried out by using a recently developed, dedicated pesticide MS library (for comprehensive GC analysis), characterized by a twin-filter search procedure, the first based on a minimum degree of spectral similarity and the second on the interactive use of linear retention indices (LRI). The library was constructed by subjecting mixtures of commonly used pesticides to GC x GC-qMS analysis and then deriving their pure mass spectra and LRI values. In order to verify the effectiveness of the approach, a pesticide-contaminated red grapefruit extract was analysed. The certainty of peak assignment was attained by exploiting both the enhanced separation power of dual-oven GC x GC and the highly effective search procedure.