Science.gov

Sample records for abatement studies chemical

  1. Chemical abatement of acid mine drainage formation

    SciTech Connect

    Steven, J.

    1987-01-01

    Chemical and thermodynamic data were used to develop a unified model of hydroxo-, sulfato-, and bisulfato-iron complexes and their stability constants in iron-sulfate solutions. Free energy of formation for each ligand series species was hypothesized to be linear in ligand number because of supporting evidence from the literature. Laboratory tests on the inhibition of acid mine drainage bacteria were conducted. Benzoic acid, sorbic acid, and sodium lauryl sulfate at low concentrations (5 to 10 mg/liter) each effectively inhibited oxidation of ferrous iron in batch cultures of Thiobacillus ferrooxidans. The rate of chemical oxidation of ferrous iron in low-pH, sterile batch reactors was not substantially affected at the tested concentrations (5 to 50 mg/liter) of any of the compounds. Low-pH cultures of Thiobacillus thioxidans significantly increased zinc sulfide dissolution rates relative to sterile controls. Sodium lauryl sulfate, benzoic acid, and sorbic acid at concentrations of 10, 25, and 50 mg/liter, respectively, in identical low-pH, batch cultures of Thiobacillus thiooxidans, were sufficient for complete inhibition of bacterial zinc sulfide dissolution. Pilot-scale experiments on the abatement of acid mine drainage formation in both fresh and weathered pyritic coal refuse were also conducted. At doses of 0.5 g/kg and 5.0 g/kg in fresh and weathered refuse, respectively, sodium benzoate, potassium sorbate, and most significantly, sodium lauryl surface, reduced the rate of iron, sulfate, and acidity production in water-leached barrels of coal refuse material.

  2. Niobium(V) saponite clay for the catalytic oxidative abatement of chemical warfare agents.

    PubMed

    Carniato, Fabio; Bisio, Chiara; Psaro, Rinaldo; Marchese, Leonardo; Guidotti, Matteo

    2014-09-15

    A Nb(V)-containing saponite clay was designed to selectively transform toxic organosulfur chemical warfare agents (CWAs) under extremely mild conditions into nontoxic products with reduced environmental impact. Thanks to the insertion of Nb(V) sites within the saponite framework, a bifunctional catalyst with strong oxidizing and acid properties was obtained. Remarkable activity and high selectivity were observed for the oxidative abatement of (2-chloroethyl)ethyl sulfide (CEES), a simulant of sulfur mustard, at room temperature with aqueous hydrogen peroxide. This performance was significantly better compared to a conventional commercial decontamination powder. PMID:25056451

  3. Compressor station noise-abatement: a case study

    SciTech Connect

    Bianucci, J.A.; Bush, R.C.; Dooher, C.A.

    1980-01-01

    This paper describes the noise abatement measures incorporated by Pacific Gas and Electric Company into the design of its Brannan Island Compressor Station. This two unit reciprocating compressor station is located within 100 feet of a state park and 600 feet of a camp site. Operating noise level data is presented and compared to design expectations.

  4. OBSERVATIONAL STUDY OF FINAL CLEANING AND AHERA CLEARANCE SAMPLING AT ASBESTOS-ABATEMENT SITES IN NEW JERSEY

    EPA Science Inventory

    A study was conducted during the summer of 1988 to document final cleaning procedures and evaluate Asbestos Hazard Emergency Response Act (AHERA) clearance air sampling practices used at 20 asbestos-abatement sites in New Jersey. Each abatement took place in a school building and...

  5. Comprehensive abatement performance pilot study: Volume 2 -- Multi-element data analyses. Final report

    SciTech Connect

    Kinateder, J.; Ma, Z.J.

    1998-07-01

    The report presents the results of the statistical analysis of multi-element data collected during a pilot study that preceded the Comprehensive Abatement Performance (CAP) Study. The goal of the CAP Study was to assess the long-term efficacy of lead-based paint abatement. For the multi-element analysis, concentrations of lead, as well as of aluminum, barium, cadmium, calcium, chromium, magnesium, nickel, potassium, titanium, and zinc in dust and soil samples were measured. Concentrations of barium, cadmium, chromium, titanium, and zinc were measured because these elements were regarded as possible constituents of paint. Concentrations of aluminum, calcium, magnesium, nickel, and potassium were measured because these elements were regarded as likely to be found in soil. The multi-element analysis was undertaken to determine whether relationships among these elements could provide a tracer for identifying the sources and pathways of lead in households. Pilot study data were used to (1) characterize the concentrations of lead, aluminum, barium, cadmium, calcium, chromium, magnesium, nickel, potassium, titanium, and zinc samples in household dust and soil; (2) measure the differences in these concentrations associated with renovation and lead-based paint abatement; and (3) investigate the relationship among the elements by sample type (i.e., samples taken from different locations).

  6. Debate over Social Studies Shows Little Sign of Abating

    ERIC Educational Resources Information Center

    Robelen, Erik W.

    2010-01-01

    The Texas board of education which consists of 15-member elected body drew national attention as a bloc of staunch conservatives largely succeeded in putting its stamp on a revised set of social studies standards. The debate was marked by tussles over such matters as the separation of church and state, the representation of minority figures and…

  7. Control of dangerous substances in discharges and microbiological abatement: European framework and a case study of an ozone disinfection system.

    PubMed

    Ostoich, M; Serena, F; Falletti, L; Fantoni, A

    2013-01-01

    Directive 2000/60/EC requires the achievement of a 'good chemical status' for surface water within pre-established dates. Disinfection is needed to achieve compulsory final microbial limit values (in Italy for wastewater discharges the parameter Escherichia coli - EC - is imposed by law with a maximum limit value of 5,000 cfu/100 mL). Liquid waste and disinfection by-products must be considered when designing appropriate monitoring of dangerous substances; the specific classes of substances must be investigated according to the typology of received wastewaters and liquid wastes (where applicable) and specific analytical techniques, with Limit of Detection (LOD) lower than the limit values, must be applied; the difficulties faced by national and regional environmental control Agencies is that these techniques have to be applied during ordinary activity and not only for research purposes. The study aims to present the control of dangerous substances, as a screening view, in wastewater treatment plant (WWTP) discharges in the province of Venice (Northern Italy) for the period 2007-2010 based on available data from institutional controls. In addition, the wastewater disinfection process with ozone applied to a medium size WWTP (45,000 Population Equivalents) is presented as a case study, with a view to assessing the microbiological abatement efficacy and the presence of dangerous substances. Discharge quality of the WWTPs in the province of Venice presented mean values that were higher than the LOD, but only for certain metals. For the Paese plant, zinc and chloroform were the only micro-pollutants detected with a higher level than the LOD. From microbiological data in the period 2006-2011 the disinfection abatement efficiency for Paese was, in most cases above 99% for EC, faecal coliform (FC), faecal streptococci (FS) while efficiency was slightly lower for total coliform (TC); however, the proposed criterion aimed at respecting 99.99% abatement was not completely

  8. Pollution Abatement and Prevention Analysis (PAPA) study. Final report, September 1993-July 1994

    SciTech Connect

    Leibel, M.L.

    1994-07-01

    This study developed and demonstrated an analytical methodology that can optimize multiple objectives, subject to programmatic and budget constraints, in the development and evaluation of pollution abatement and prevention investment strategies supporting US Army activities and facilities. It possesses the capability to modify inputs to determine changes an impacts of the different investment strategies produced. Outputs include investments strategies which address what should be bought, when, and where, the costs of the investment, and the benefits derived in terms of pollution reduced (in volume), (OS) and energy savings. Products, can be produced at the Army level, MACOM, state, region, or installation. The methodology is inherently flexible and transferable such that it can readily incorporate changes in policy, data elements, and analytical approach to develop and evaluate investment strategies in other Arm y environmental programs. The PAPA Investment Model (PIM) is a multiobjective, mixed integer linear program, written in C + +, using EXCEL spreadsheet format input.

  9. Sulfur deposition simulations over China, Japan, and Korea: a model intercomparison study for abating sulfur emission.

    PubMed

    Kim, Cheol-Hee; Chang, Lim-Seok; Meng, Fan; Kajino, Mizuo; Ueda, Hiromasa; Zhang, Yuanhang; Son, Hye-Young; Lee, Jong-Jae; He, Youjiang; Xu, Jun; Sato, Keiichi; Sakurai, Tatsuya; Han, Zhiwei; Duan, Lei; Kim, Jeong-Soo; Lee, Suk-Jo; Song, Chang-Keun; Ban, Soo-Jin; Shim, Shang-Gyoo; Sunwoo, Young; Lee, Tae-Young

    2012-11-01

    In response to increasing trends in sulfur deposition in Northeast Asia, three countries in the region (China, Japan, and Korea) agreed to devise abatement strategies. The concepts of critical loads and source-receptor (S-R) relationships provide guidance for formulating such strategies. Based on the Long-range Transboundary Air Pollutants in Northeast Asia (LTP) project, this study analyzes sulfur deposition data in order to optimize acidic loads over the three countries. The three groups involved in this study carried out a full year (2002) of sulfur deposition modeling over the geographic region spanning the three countries, using three air quality models: MM5-CMAQ, MM5-RAQM, and RAMS-CADM, employed by Chinese, Japanese, and Korean modeling groups, respectively. Each model employed its own meteorological numerical model and model parameters. Only the emission rates for SO(2) and NO(x) obtained from the LTP project were the common parameter used in the three models. Three models revealed some bias from dry to wet deposition, particularly the latter because of the bias in annual precipitation. This finding points to the need for further sensitivity tests of the wet removal rates in association with underlying cloud-precipitation physics and parameterizations. Despite this bias, the annual total (dry plus wet) sulfur deposition predicted by the models were surprisingly very similar. The ensemble average annual total deposition was 7,203.6 ± 370 kt S with a minimal mean fractional error (MFE) of 8.95 ± 5.24 % and a pattern correlation (PC) of 0.89-0.93 between the models. This exercise revealed that despite rather poor error scores in comparison with observations, these consistent total deposition values across the three models, based on LTP group's input data assumptions, suggest a plausible S-R relationship that can be applied to the next task of designing cost-effective emission abatement strategies. PMID:22869502

  10. Noise Abatement

    NASA Technical Reports Server (NTRS)

    1983-01-01

    SMART, Sound Modification and Regulated Temperature compound, is a liquid plastic mixture with exceptional energy and sound absorbing qualities. It is derived from a very elastic plastic which was an effective noise abatement material in the Apollo Guidance System. Discovered by a NASA employee, it is marketed by Environmental Health Systems, Inc. (EHS). The product has been successfully employed by a diaper company with noisy dryers and a sugar company with noisy blowers. The company also manufactures an audiometric test booth and acoustical office partitions.

  11. Effects of olive mill wastewater physico-chemical treatments on polyphenol abatement and Italian ryegrass (Lolium multiflorum Lam.) germinability.

    PubMed

    Barbera, A C; Maucieri, C; Ioppolo, A; Milani, M; Cavallaro, V

    2014-04-01

    Direct spreading on agricultural lands may represent an environmentally friendly disposal method and a possible use of water and nutrients from olive mill wastewaters (OMWs). However, the agronomic use of OMWs is limited, among others by polyphenols, which exert phytotoxic effects. Activated charcoal (AC) has been recognized as a very effective agent for polyphenol abatement, as it enables an irreversible process of phenol adsorption. Addition of calcium hydroxide (Ca(OH)2) has also been described as a cheap and effective method in polyphenols abatement. However, the effects of Ca(OH)2 addition to OMW on seed germination are unclear. In this paper, the effects of AC and/or Ca(OH)2 on OMW polyphenols abatement, and Lolium multiflorum seed germination have been investigated. The highest polyphenols removal, approximately 95%, was observed when 80 g L(-1) of AC was added to OMWs (the maximum dose in this investigation). The addition of Ca(OH)2 not only improved the effectiveness of the AC treatment but also resulted in a significant rise in Lolium seed germination at the highest AC doses (60 and 80 g L(-1)). Considering the high salinity (7300 μS cm(-1)) of these wastewaters, low quantities of Ca(OH)2 may also exert a protective effect on soil structure counteracting the sodium-induced dispersion through the binding action of calcium cation on clays and organic matter. PMID:24289894

  12. A Study of Interior Landscape Plants for Indoor Air Pollution Abatement

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.; Douglas, Willard L.; Bounds, Keith

    1989-01-01

    Previously, preliminary data on the ability of a group of common indoor plants to remove organic chemical from indoor air was presented. The group of plants chosen for this study was determined by joint agreement between NASA and the Associated Landscape Contractors of America. The chemicals chosen for study were benzene, trichloroethylene, and formaldehyde. The results show that plants can play a major role in removal of organic chemicals from indoor air.

  13. Heterogeneous Photocatalysis and Photoelectrocatalysis: From Unselective Abatement of Noxious Species to Selective Production of High-Value Chemicals.

    PubMed

    Augugliaro, Vincenzo; Camera-Roda, Giovanni; Loddo, Vittorio; Palmisano, Giovanni; Palmisano, Leonardo; Soria, Javier; Yurdakal, Sedat

    2015-05-21

    Heterogeneous photocatalysis and photoelectrocatalysis have been considered as oxidation technologies to abate unselectively noxious species. This article focuses instead on the utilization of these methods for selective syntheses of organic molecules. Some promising reactions have been reported in the presence of various TiO2 samples and the important role played by the amorphous phase has been discussed. The low solubility of most of the organic compounds in water limits the utilization of photocatalysis. Dimethyl carbonate has been proposed as an alternative green organic solvent. The recovery of the products by coupling photocatalysis with pervaporation membrane technology seems to be a solution for future industrial applications. As far as photoelectrocatalysis is concerned, a decrease in recombination of the photogenerated pairs occurs, enhancing the rate of the oxidation reactions and the quantum yield. Another benefit is to avoid reaction(s) between the intermediates and the substrate, as anodic and cathodic reactions take place in different places. PMID:26263277

  14. FEASIBILITY OF ELK CREEK ACID MINE DRAINAGE ABATEMENT PROJECT

    EPA Science Inventory

    A study was conducted within the Elk Creek Watershed, West Virginia to determine the technical and economic feasibility of three acid mine drainage abatement techniques. Alkaline regarding and slurry trench construction were established as technically and economically viable abat...

  15. Insect abatement system

    NASA Technical Reports Server (NTRS)

    Spiro, Clifford Lawrence (Inventor); Burnell, Timothy Brydon (Inventor); Wengrovius, Jeffrey Hayward (Inventor)

    1997-01-01

    An insect abatement system prevents adhesion of insect debris to surfaces which must be kept substantially free of insect debris. An article is coated with an insect abatement coating comprising polyorganosiloxane with a Shore A hardness of less than 50 and a tensile strength of less than 4 MPa. A method for preventing the adhesion of insect debris to surfaces includes the step of applying an insect abatement coating to a surface which must be kept substantially free of insect debris.

  16. AHERA CLEARANCE AT TWENTY ABATEMENT SITES

    EPA Science Inventory

    A study was conducted during the summer of 1988 to document Asbestos Hazard Emergency Response Act (AHERA) clearance air sampling practices and clearance concentrations of airborne asbestos at 20 asbestos-abatement sites in New Jersey. ach abatement took place in a school buildin...

  17. AHERA CLEARANCE AT TWENTY ABATEMENT SITES

    EPA Science Inventory

    A study was conducted during the summer of 1988 to document Asbestos Hazard Emergency Response Act (AHERA) clearance air-sampling practices and clearance concentrations of airborne asbestos at 20 asbestos-abatement sites in New Jersey. Each abatement took place in a school buildi...

  18. Chemical Industry Bandwidth Study

    SciTech Connect

    none,

    2006-12-01

    The Chemical Bandwidth Study provides a snapshot of potentially recoverable energy losses during chemical manufacturing. The advantage of this study is the use of "exergy" analysis as a tool for pinpointing inefficiencies.

  19. OPTIONS FOR ABATING GREENHOUSE GASES FROM EXHAUST STREAMS.

    SciTech Connect

    FTHENAKIS,V.

    2001-12-01

    This report examines different alternatives for replacing, treating, and recycling greenhouse gases. It is concluded that treatment (abatement) is the only viable short-term option. Three options for abatement that were tested for use in semiconductor facilities are reviewed, and their performance and costs compared. This study shows that effective abatement options are available to the photovoltaic (PV) industry, at reasonable cost.

  20. Stream pollution as a negative collective externality and its abatement as a public good: a theoretical analysis and a case study

    SciTech Connect

    Bolless, J.

    1982-01-01

    This study focuses on the relationship between the nature of public goods and the organization for their supply, in the particular context of stream pollution. The theoretical analysis of stream pollution as a negative externality and its abatement is further developed in a case study of one river basin, the Fox River, in Kane County in northern Illinois. Stream pollution was found to be a unique externality in that it is cumulative, mobile, and unidirectional, i.e., it always flows in one direction and, thus, downstream communities suffer from the pollution of any of the communities located upstream. The asymmetry of the externality prevents bargaining, while the cumulative effect rules out a noncoordinated action by a single community. Thus, government intervention is needed to supply the good in order to abate the externality. However, since water has more than a single usage, the question of the degree to which the water should be cleaned may create an inadequate abatement for communities with higher water quality needs than the standard, on the one hand, as well as new negative externalities of overinvestment for other communities which require a lesser degree of purity than the one imposed.

  1. High temperature abatement of acid gases from waste incineration. Part II: Comparative life cycle assessment study

    SciTech Connect

    Biganzoli, Laura; Racanella, Gaia; Marras, Roberto; Rigamonti, Lucia

    2015-01-15

    Highlights: • Two scenarios of acid gases removal in WTE plants were compared in an LCA study. • A detailed inventory based on primary data has been reported for the production of the new dolomitic sorbent. • Results show that the comparison between the two scenarios does not show systematic differences. • The potential impacts are reduced only if there is an increase in the energy efficiency of the WTE plant. - Abstract: The performances of a new dolomitic sorbent, named Depurcal®MG, to be directly injected at high temperature in the combustion chamber of Waste-To-Energy (WTE) plants as a preliminary stage of deacidification, were experimentally tested during full-scale commercial operation. Results of the experimentations were promising, and have been extensively described in Biganzoli et al. (2014). This paper reports the Life Cycle Assessment (LCA) study performed to compare the traditional operation of the plants, based on the sole sodium bicarbonate feeding at low temperature, with the new one, where the dolomitic sorbent is injected at high temperature. In the latter the sodium bicarbonate is still used, but at lower rate because of the decreased load of acid gases entering the flue gas treatment line. The major goal of the LCA was to make sure that a burden shifting was not taking place somewhere in the life cycle stages, as it might be the case when a new material is used in substitution of another one. According to the comparative approach, only the processes which differ between the two operational modes were included in the system boundaries. They are the production of the two reactants and the treatment of the corresponding solid residues arising from the neutralisation of acid gases. The additional CO{sub 2} emission at the stack of the WTE plant due to the activation of the sodium bicarbonate was also included in the calculation. Data used in the modelling of the foreground system are primary, derived from the experimental tests described in

  2. High temperature abatement of acid gases from waste incineration. Part II: Comparative life cycle assessment study.

    PubMed

    Biganzoli, Laura; Racanella, Gaia; Marras, Roberto; Rigamonti, Lucia

    2015-01-01

    The performances of a new dolomitic sorbent, named Depurcal®MG, to be directly injected at high temperature in the combustion chamber of Waste-To-Energy (WTE) plants as a preliminary stage of deacidification, were experimentally tested during full-scale commercial operation. Results of the experimentations were promising, and have been extensively described in Biganzoli et al. (2014). This paper reports the Life Cycle Assessment (LCA) study performed to compare the traditional operation of the plants, based on the sole sodium bicarbonate feeding at low temperature, with the new one, where the dolomitic sorbent is injected at high temperature. In the latter the sodium bicarbonate is still used, but at lower rate because of the decreased load of acid gases entering the flue gas treatment line. The major goal of the LCA was to make sure that a burden shifting was not taking place somewhere in the life cycle stages, as it might be the case when a new material is used in substitution of another one. According to the comparative approach, only the processes which differ between the two operational modes were included in the system boundaries. They are the production of the two reactants and the treatment of the corresponding solid residues arising from the neutralisation of acid gases. The additional CO2 emission at the stack of the WTE plant due to the activation of the sodium bicarbonate was also included in the calculation. Data used in the modelling of the foreground system are primary, derived from the experimental tests described in Biganzoli et al. (2014) and from the dolomitic sorbent production plant. The results of the LCA show minor changes in the potential impacts between the two operational modes of the plants. These differences are for 8 impact categories in favour of the new operational mode based on the addition of the dolomitic sorbent, and for 7 impact categories in favour of the traditional operation. A final evaluation was conducted on the potential

  3. Advanced Chemical Propulsion Study

    NASA Technical Reports Server (NTRS)

    Woodcock, Gordon; Byers, Dave; Alexander, Leslie A.; Krebsbach, Al

    2004-01-01

    A study was performed of advanced chemical propulsion technology application to space science (Code S) missions. The purpose was to begin the process of selecting chemical propulsion technology advancement activities that would provide greatest benefits to Code S missions. Several missions were selected from Code S planning data, and a range of advanced chemical propulsion options was analyzed to assess capabilities and benefits re these missions. Selected beneficial applications were found for higher-performing bipropellants, gelled propellants, and cryogenic propellants. Technology advancement recommendations included cryocoolers and small turbopump engines for cryogenic propellants; space storable propellants such as LOX-hydrazine; and advanced monopropellants. It was noted that fluorine-bearing oxidizers offer performance gains over more benign oxidizers. Potential benefits were observed for gelled propellants that could be allowed to freeze, then thawed for use.

  4. Noise Abatement Materials

    NASA Technical Reports Server (NTRS)

    1986-01-01

    A former NASA employee who discovered a kind of plastic that soaked up energy, dampened vibrations, and was a good noise abatement material, founded a company to market noise deadening adhesives, sheets, panels and enclosures. Known as SMART products, they are 75-80% lighter than ordinary soundproofing material and have demonstrated a high degree of effectiveness. The company, Varian Associates, makes enclosures for high voltage terminals and other electronic system components, and easily transportable audiometric test booths.

  5. Environmental regulation, productive efficiency and cost of pollution abatement: a case study of the sugar industry in India.

    PubMed

    Murty, M N; Kumar, Surender; Paul, Mahua

    2006-04-01

    In this paper the input distance function is estimated for the Indian Sugar industry under alternative assumptions of weak and strong disposability of bad outputs. The estimated distance function is used to make the estimates of environmental efficiency, Malmquist productivity index and shadow prices of pollutants. The technical efficiency measure estimated under the assumption of weak disposability of bad outputs is utilized to test the Porter hypothesis. Marginal costs of pollution abatement functions are estimated for different pollutants of water. Pollutant specific taxes are computed using the tax-standards method. PMID:16181728

  6. ASBESTOS CONCENTRATIONS TWO YEARS AFTER ABATEMENT IN SEVENTEEN SCHOOLS

    EPA Science Inventory

    Airborne asbestos concentrations were measured at 17 schools that underwent an asbestos abatement 2 years before in 1988. These 17 schools, which involved 20 abatement sites, were part of a study conducted by the U.S. Environmental Protection Agency (EPA) and the New Jersey Depar...

  7. ASBESTOS CONCENTRATIONS IN TWO YEARS AFTER ABATEMENT IN SEVENTEEN SCHOOLS

    EPA Science Inventory

    Airborne asbestos concentrations were measured at 17 schools that underwent an asbestos abatement 2 years before in 1988. hese 17 schools, which involved 20 abatement sites, were part of a study conducted by the U.S Environmental Protection Agency (EPA) and the New Jersey Departm...

  8. Emission Abatement System

    DOEpatents

    Bromberg, Leslie; Cohn, Daniel R.; Rabinovich, Alexander

    2003-05-13

    Emission abatement system. The system includes a source of emissions and a catalyst for receiving the emissions. Suitable catalysts are absorber catalysts and selective catalytic reduction catalysts. A plasma fuel converter generates a reducing gas from a fuel source and is connected to deliver the reducing gas into contact with the absorber catalyst for regenerating the catalyst. A preferred reducing gas is a hydrogen rich gas and a preferred plasma fuel converter is a plasmatron. It is also preferred that the absorber catalyst be adapted for absorbing NO.sub.x.

  9. Biological abatement of cellulase inhibitors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bio-abatement uses a fungus to metabolize and remove fermentation inhibitors. To determine whether bio-abatement could alleviate enzyme inhibitor effects observed in biomass liquors after pretreatment, corn stover at 10% (w/v) solids was pretreated with either dilute acid or liquid hot water. The ...

  10. The Effect of Chemical Amendments Used for Phosphorus Abatement on Greenhouse Gas and Ammonia Emissions from Dairy Cattle Slurry: Synergies and Pollution Swapping.

    PubMed

    Brennan, Raymond B; Healy, Mark G; Fenton, Owen; Lanigan, Gary J

    2015-01-01

    Land application of cattle slurry can result in incidental and chronic phosphorus (P) loss to waterbodies, leading to eutrophication. Chemical amendment of slurry has been proposed as a management practice, allowing slurry nutrients to remain available to plants whilst mitigating P losses in runoff. The effectiveness of amendments is well understood but their impacts on other loss pathways (so-called 'pollution swapping' potential) and therefore the feasibility of using such amendments has not been examined to date. The aim of this laboratory scale study was to determine how the chemical amendment of slurry affects losses of NH3, CH4, N2O, and CO2. Alum, FeCl2, Polyaluminium chloride (PAC)- and biochar reduced NH3 emissions by 92, 54, 65 and 77% compared to the slurry control, while lime increased emissions by 114%. Cumulative N2O emissions of cattle slurry increased when amended with alum and FeCl2 by 202% and 154% compared to the slurry only treatment. Lime, PAC and biochar resulted in a reduction of 44, 29 and 63% in cumulative N2O loss compared to the slurry only treatment. Addition of amendments to slurry did not significantly affect soil CO2 release during the study while CH4 emissions followed a similar trend for all of the amended slurries applied, with an initial increase in losses followed by a rapid decrease for the duration of the study. All of the amendments examined reduced the initial peak in CH4 emissions compared to the slurry only treatment. There was no significant effect of slurry amendments on global warming potential (GWP) caused by slurry land application, with the exception of biochar. After considering pollution swapping in conjunction with amendment effectiveness, the amendments recommended for further field study are PAC, alum and lime. This study has also shown that biochar has potential to reduce GHG losses arising from slurry application. PMID:26053923

  11. The Effect of Chemical Amendments Used for Phosphorus Abatement on Greenhouse Gas and Ammonia Emissions from Dairy Cattle Slurry: Synergies and Pollution Swapping

    PubMed Central

    Brennan, Raymond B.; Healy, Mark G.; Fenton, Owen; Lanigan, Gary J.

    2015-01-01

    Land application of cattle slurry can result in incidental and chronic phosphorus (P) loss to waterbodies, leading to eutrophication. Chemical amendment of slurry has been proposed as a management practice, allowing slurry nutrients to remain available to plants whilst mitigating P losses in runoff. The effectiveness of amendments is well understood but their impacts on other loss pathways (so-called ‘pollution swapping’ potential) and therefore the feasibility of using such amendments has not been examined to date. The aim of this laboratory scale study was to determine how the chemical amendment of slurry affects losses of NH3, CH4, N2O, and CO2. Alum, FeCl2, Polyaluminium chloride (PAC)- and biochar reduced NH3 emissions by 92, 54, 65 and 77% compared to the slurry control, while lime increased emissions by 114%. Cumulative N2O emissions of cattle slurry increased when amended with alum and FeCl2 by 202% and 154% compared to the slurry only treatment. Lime, PAC and biochar resulted in a reduction of 44, 29 and 63% in cumulative N2O loss compared to the slurry only treatment. Addition of amendments to slurry did not significantly affect soil CO2 release during the study while CH4 emissions followed a similar trend for all of the amended slurries applied, with an initial increase in losses followed by a rapid decrease for the duration of the study. All of the amendments examined reduced the initial peak in CH4 emissions compared to the slurry only treatment. There was no significant effect of slurry amendments on global warming potential (GWP) caused by slurry land application, with the exception of biochar. After considering pollution swapping in conjunction with amendment effectiveness, the amendments recommended for further field study are PAC, alum and lime. This study has also shown that biochar has potential to reduce GHG losses arising from slurry application. PMID:26053923

  12. Model curriculum for asbestos abatement workers

    SciTech Connect

    1993-12-31

    These slides are part of a 4-day-course intended for those persons seeking accreditation as asbestos abatement workers. The course presents a straight forward, easy-to-read approach to learning the basics of asbestos abatement.

  13. 23 CFR 772.11 - Noise abatement.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... OF HIGHWAY TRAFFIC NOISE AND CONSTRUCTION NOISE § 772.11 Noise abatement. (a) In determining and abating traffic noise impacts, primary consideration is to be given to exterior areas. Abatement will usually be necessary only where frequent human use occurs and a lowered noise level would be of...

  14. 23 CFR 772.11 - Noise abatement.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... OF HIGHWAY TRAFFIC NOISE AND CONSTRUCTION NOISE § 772.11 Noise abatement. (a) In determining and abating traffic noise impacts, primary consideration is to be given to exterior areas. Abatement will usually be necessary only where frequent human use occurs and a lowered noise level would be of...

  15. Lead Abatement Worker Skill Standards.

    ERIC Educational Resources Information Center

    Laborers-AGC Education and Training Fund, Pomfret Center, CT.

    This document identifies skill standards for lead abatement in a manner that is easy to understand, useful, and meaningful to workers, educators, trainers, labor leaders, contractors, and project owners. To meet the needs of the various users of this document who will have a different application of the standards and seek different information,…

  16. Asbestos Abatement--Practical Considerations.

    ERIC Educational Resources Information Center

    Sedrel, Roy A.

    Illinois Senate Bill 1644, the recently passed "Asbestos Abatement Act," requires all schools in the state, public and private alike, to remove friable asbestos by whichever comes first: July 1, 1989, or 3 years following the establishment of a system for state funding for corrective action. This document addresses practical considerations in…

  17. Biological abatement of enzyme inhibitors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lignocellulose pretreatments release phenolic compounds that cause enzyme inhibition and deactivation. Bio-abatement, the biological removal of furfurals, acetic acid and phenolics, may utilize fungal fermentation to metabolize these compounds to CO2, water, cell mass, and heat. Our work with Coni...

  18. Asbestos Abatement: Start to Finish.

    ERIC Educational Resources Information Center

    Makruski, Edward D.

    1984-01-01

    An EPA survey of the largest school districts in the nation revealed that over 50 percent have not inspected for asbestos and two-thirds have failed to notify parents adequately. Seven steps are therefore provided for successful asbestos abatement, in anticipation of tougher regulations now under consideration. (TE)

  19. Oak Ridge Gaseous Diffusion Plant Biological Monitoring and Abatement Program for Mitchell Branch

    SciTech Connect

    Loar, J.M.; Adams, S.M.; Kszos, L.A.; Ryon, M.G.; Smith, J.G.; Southworth, G.R.; Stewart, A.J.

    1992-01-01

    A proposed Biological Monitoring and Abatement Program (BMAP) for the Oak Ridge Gaseous Diffusion Plant (ORGDP; currently the Oak Ridge K-25 Site) was prepared in December 1986, as required by the modified National Pollutant Discharge Elimination System (NPDES) permit that was issued on September 11, 1986. The effluent discharges to Mitchell Branch are complex, consisting of trace elements, organic chemicals, and radionuclides in addition to various conventional pollutants. Moreover, the composition of these effluent streams will be changing over time as various pollution abatement measures are implemented over the next several years. Although contaminant inputs to the stream originate primarily as point sources from existing plant operations, area sources, such as the classified burial grounds and the K-1407-C holding pond, can not be eliminated as potential sources of contaminants. The proposed BMAP consists of four tasks. These tasks include (1) ambient toxicity testing, (2) bioaccumulation studies, (3) biological indicator studies, and (4) ecological surveys of the benthic invertebrate and fish communities. BMAP will determine whether the effluent limits established for ORGDP protect the designated use of the receiving stream (Mitchell Branch) for growth and propagation of fish and aquatic life. Another objective of the program is to document the ecological effects resulting from various pollution abatement projects, such as the Central Neutralization Facility.

  20. MECHANISTIC STUDIES AND DESIGN OF HIGHLY ACTIVE CUPRATE CATALYSTS FOR THE DIRECT DECOMPOSITION AND SELECTIVE REDUCTION OF NITRIC OXIDE AND HYDROCARBONS TO NITROGEN FOR ABATEMENT OF STACK EMISSIONS

    SciTech Connect

    1998-04-30

    A flow trough type catalytic reactor system was adequately modified for NO related catalytic and adsorption measurements, including the on-line connection of a digital chemiluminescent NO-NO{sub x} analyzer to the reactor outlet system. Moreover, we have largely completed the installation of an FTIR coupled catalytic system containing a HTEC cell for high temperature DRIFT studies. Three different barium cuprate samples, Ba{sub 2}CuO{sub 3}, BaCuO{sub 2}, and Ba{sub 2}Cu{sub 3}O{sub 5} were synthesized and characterized by powder XRD for catalytic tests. Prior to catalytic studies over these cuprates, a new, liquid indium based supported molten metal catalyst (In-SMMC) was tested in the reduction of NO by various reductants. In the presence of excess O{sub 2} and H{sub 2}O, the In-SMMC proved to be more active for the selective catalytic reduction (SCR) of NO to N{sub 2} by ethanol than most other catalysts. Using C{sub 1}-C{sub 3} alcohols as reductants, self sustained periodic oscillations observed in the NO{sub x} concentrations of reactor effluents indicated the first time that radical intermediates can be involved in the SCR of NO by alcohols. Further, In-SMMC is the only effective and water tolerant SCR catalyst reported thus far which contains SiO{sub 2} support. Thus, this novel catalyst opens up a promising new alternative for developing an effective and durable catalyst for NO{sub x} abatement in stack emission.

  1. Measuring the benefits from air pollution abatement on human health and welfare: a case study of Jacksonville, Florida

    SciTech Connect

    Erfani-Ezati, G.

    1984-01-01

    The purpose of this study was to test benefit measures of air pollution to human health and welfare. Two market approaches, labor market (wage rate) and housing market (property value), were employed to estimate benefits from improvements in air quality. Indices of air pollution used in this study were sulfur dioxide (SO/sub 2/) and total suspended particulate matter (TSP). Using the labor market approach as a measure of benefits from improved air quality, a Mortality Effect Model (MEM) was developed. Then, the model was utilized to quantify the estimates of the pollution mortality relationship for the city of Jacksonville. The resulting pollution related mortality function was then monetized by applying estimates of individual's willingness to pay for mortality reductions. The MEM was estimated using multiple regression analysis. TSP showed no statistically significant association with mortality rates. The significance of the estimated coefficient for the pollution variable SO/sub 2/ supported the contention that some form of air pollution bears a positive and significant relationship to mortality rates. By utilizing a willingness to pay estimate for mortality reductions, it was concluded that individuals in Jacksonville would be willing to pay a minimum of $10 million annually, in order to maintain SO/sub 2/ concentrations at a level of 1% below the average for 1972.

  2. Lead paint abatement -- A technological review

    SciTech Connect

    Draper, A.C. III; Kapuscik, D.

    1994-12-31

    Abatement of lead from various surfaces proves to be a rapidly developing industry. Removal techniques and effectiveness varies greatly with varying substrates (wood, concrete, steel, etc.) and surface configurations including interior/exterior considerations, habitability and anticipated retrofit. Numerous technologies advances, and/or adaptations of long accepted removal techniques have recently emerged. Some of the more commonly used removal procedures including vacuum blasting, chemical stripping, scarifiers, grinders, sanders, etc. will be reviewed. Specific emphasis will be placed upon mode of application, positive and negative environmental aspects, and varying emissions generated. Personnel sampling data will be discussed with respect to associated personal protective equipment impact to derive the most cost productive environmentally conscious alternatives.

  3. URBAN SOIL LEAD ABATEMENT DEMONSTRATION PROJECT: VOLUME I, U.S. EPA INTEGRATED REPORT

    EPA Science Inventory

    The Urban Soil Lead Abatement Demonstration Project (USLADP), known also as the A Three City Lead Study,was authorized in 1986 under Section 111(b)(6) of the Superfund Amendments and Reauthorization Act (SARA), which mandated that EPA conduct soil lead abatement projects in up to...

  4. 76 FR 39368 - Migratory Bird Permits; Abatement Regulations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-06

    ... abatement permit holder may use captive-bred raptors held under his or her migratory bird master falconry permit for abatement activities without transferring them to his or her abatement permit, provided the... used under his or her abatement permit. Raptors used under a Federal abatement permit must be...

  5. Asbestos concentrations two years after abatement in seventeen schools. Final summary report

    SciTech Connect

    Kominsky, J.R.; Freyberg, R.W.; Brownlee, J.A.; Gerber, D.R.

    1992-03-01

    Airborne asbestos concentrations were measured at 17 schools that underwent an asbestos abatement 2 years before in 1988. These 17 schools, which involved 20 abatement sites, were part of a study conducted by the U.S. Environmental Protection Agency (EPA) and the New Jersey Department of Health (NJDOH) in 1988. The 1988 study showed that asbestos concentrations measured independently by the NJDOH and EPA during the clearance phase of the abatement were elevated in the abatement and perimeter areas compared with outdoor concentrations. The present study was conducted to determine the current levels of airborne asbestos under simulated occupancy conditions and to determine whether the elevated levels found during the clearance phase were still present 2 years after abatement. In 1990, four sites showed significantly higher mean asbestos concentrations inside the building (i.e., the previously abated area and/or perimeter area) compared with those outdoors (p<0.05). In 1990, the mean asbestos concentration measured in the perimeter area at one site and in the previously abated area at two sites were significantly higher than those in 1988 (p<0.05). Variations in asbestos levels between 1988 and 1990 may be due to sampling techniques (passive and aggressive versus modified aggressive), residual air-entrainable asbestos from the 1988 abatement, or air-entrainable asbestos from operations and maintenance activities since 1988.

  6. Nitrogen oxide abatement by distributed fuel addition

    SciTech Connect

    Wendt, J.O.L.; Meraab, J.

    1988-03-25

    The purpose of this project is to develop techniques for nitrogen oxides abatement by distributed fuel addition. The major nitrogen oxide of interest is Nitric Oxide (NO), a precursor to premature forest damage and to acid rain. Recently interest has also been evoked with respect to an additional oxide of nitrogen, namely Nitrous Oxide (N{sub 2}O). Therefore, abatement measures for NO{sub x} are being investigated to determine their influence on N{sub 2}O as well. This report briefly describes the significance of N{sub 2}O emissions to the environment and the urgent need to develop techniques that can reduce emissions of both NO and N{sub 2}O. Reburning through distributed fuel addition may be an effective technique for NO{sub x} (mainly NO) emission control as described in the previous quarterly report. Reburning may also be effective in reducing N{sub 2}O levels. A technique for N{sub 2}O measurement by gas chromatography/electron capture detection was developed during this quarter, and is described in this report. This analysis technique will be used in the proposed experimental study to investigate the effectiveness of reburning on N{sub 2}O control.

  7. [Legal aspects of noise abatement].

    PubMed

    Kierski, W S

    1976-12-01

    Noise abatement is a problem of technology, medicine, law, and education. In the technical field, the problem of avoiding hazards is the primary one. In respect of encroachment upon neighbours mutual regard should be the foremost consideration. From the legal angle, a distinction is made between protection of the individial-above all under the provisions of the German Civil Code (Bürgerliches Gesetzbuch)-and of the community-under the provisions of criminal law and administrative law. Future legislation will have to concentrate increasingly upon governmental control measures especially with a view to prevention, instead of the issue of protection of the individual. PMID:1002088

  8. QUANTITATIVE EVALUATION OF HEPA FILTRATION UNITS AT ASBESTOS ABATEMENT SITES

    EPA Science Inventory

    A study was conducted to determine-the filtering efficiencies of 31 high efficiency particulate air (HEPA) filtration units in use at asbestos-abatement projects. article-removal efficiencies for these units ranged from 90.53 to > 99.99 percent. ineteen (61%) of the units tested ...

  9. PHOTOCATALYTIC OXIDATION FOR NOx ABATEMENT: DEVELOPMENT OF A KINETIC EXPRESSION AND DESIGN TOOLS

    SciTech Connect

    Rajiv Srivastava; M. A. Ebadian

    2000-09-15

    The ''Nitrogen Oxides Emission Reduction Program'' and ''Ozone Non-Attainment Program'' in the 1990 Clean Air Act provide guidelines for controlling NOx (NO and NO{sub 2}) emissions in new and existing stationary sources. NOx emissions have local (air quality), regional (acid rain), and global (ozone production) consequences. This study aids in developing the photocatalyst technology that has potential for use in abatement of NOx. The objective of the proposed project is to apply the principles of chemical engineering fundamentals--reaction kinetics, transport phenomena and thermodynamics--in the process design for a system that will utilize a photocatalytic reactor to oxidize NOx to nitric acid (HNO{sub 3}). HNO{sub 3} can be more easily trapped than NOx on adsorbent surfaces or in water. The project dealt with the engineering aspect of the gas-solid heterogeneous oxidation of NOx. The experiments were conducted in a photocatalyst wash-coated glass flow tube reactor. A mathematical model was developed based on a rigorous description of the physical and chemical processes occurring in the reactor. The mathematical model took into account (1) intrinsic reaction kinetics (i.e., true reaction rates), (2) transport phenomena that deal with the mass transfer effects in the reactor, and (3) the geometry of the reactor. The experimental results were used for validation of the mathematical model that provides the basis for a versatile and reliable method for the purpose of design, scale-up and process control. The NOx abatement was successfully carried out in a flow tube reactor surrounded by black lights under the exploratory grant. Due to lack of funds, a comprehensive kinetic analysis for the photocatalytic reaction scheme could not be carried out. The initial experiments look very promising for use of photocatalysis for NOx abatement.

  10. (Laser enhanced chemical reaction studies)

    SciTech Connect

    Not Available

    1992-01-01

    Experimental studies of dynamic molecular processes are described with particular emphasis on the use of a powerful infrared diode laser probe technique developed in our laboratory. This technique allows us to determine the final states of CO{sub 2} (and other molecules) produced by collisions, photofragmentation, or chemical reactions with a spectral resolution of 0.0003 cm{sup {minus}1} and a time resolution of 10{sup {minus}7} sec. Such high spectral resolution provides a detailed picture of the vibrational and rotational states of molecules produced by these dynamic events. We have used this experimental method to probe collisions between hot hydrogen/deuterium atoms and CO{sub 2}, between O({sup 1}D) atoms and CO{sub 2}, to study the final states of DC1 molecules produced as a result of the reactions of hot Cl atoms, and to investigate the dynamics of the reaction between OH and CO molecules. Advances in our techniques over the past two years have allowed us to identify and study more than 200 final rotational states in ten different vibrational levels of CO{sub 2} encompassing all 3 normal modes, many overtones, and combination states of the molecule. We have extended the technique to probe a variety of new molecules such as OCS, N{sub 2}O, DCl, and CS{sub 2}. All of this work is aimed at providing experimental tests for polyatomic molecule potential energy surfaces, chemical transition states in complex systems, and theories of reaction dynamic in molecules with more than 3 atoms.

  11. Soil lead abatement and children's blood lead levels in an urban setting.

    PubMed Central

    Farrell, K P; Brophy, M C; Chisolm, J J; Rohde, C A; Strauss, W J

    1998-01-01

    OBJECTIVES: The effect of abating soil lead was assessed among Baltimore children. The hypothesis was that a reduction of 1000 parts per million would reduce children's blood lead levels by 0.14 to 0.29 mumol/L (3-6 micrograms/dL). METHODS: In 2 neighborhoods (study and control), 187 children completed the protocol. In the study area, contaminated soil was replaced with clean soil. RESULTS: Soil lead abatement in this study did not lower children's blood lead. CONCLUSIONS: Although it did not show an effect in this study, soil lead abatement may be useful in certain areas. PMID:9842383

  12. Chemical Information: Print. Directed Study.

    ERIC Educational Resources Information Center

    Stone, Catherine C.

    This report provides a survey and evaluation of chemical information literature. Contained in this survey are an overview of the chemical literature field, comments on obtaining access to this literature and annotated bibliographies of primary, secondary, and tertiary sources as well as special topics. Primary sources include journals, patents,…

  13. Advanced Chemical Propulsion System Study

    NASA Technical Reports Server (NTRS)

    Portz, Ron; Alexander, Leslie; Chapman, Jack; England, Chris; Henderson, Scott; Krismer, David; Lu, Frank; Wilson, Kim; Miller, Scott

    2007-01-01

    A detailed; mission-level systems study has been performed to show the benefit resulting from engine performance gains that will result from NASA's In-Space Propulsion ROSS Cycle 3A NRA, Advanced Chemical Technology sub-topic. The technology development roadmap to accomplish the NRA goals are also detailed in this paper. NASA-Marshall and NASA-JPL have conducted mission-level studies to define engine requirements, operating conditions, and interfaces. Five reference missions have been chosen for this analysis based on scientific interest, current launch vehicle capability and trends in space craft size: a) GTO to GEO, 4800 kg, delta-V for GEO insertion only approx.1830 m/s; b) Titan Orbiter with aerocapture, 6620 kg, total delta V approx.210 m/s, mostly for periapsis raise after aerocapture; c) Enceladus Orbiter (Titan aerocapture) 6620 kg, delta V approx.2400 m/s; d) Europa Orbiter, 2170 kg, total delta V approx.2600 m/s; and e) Mars Orbiter, 2250 kg, total delta V approx.1860 m/s. The figures of merit used to define the benefit of increased propulsion efficiency at the spacecraft level include propulsion subsystem wet mass, volume and overall cost. The objective of the NRA is to increase the specific impulse of pressure-fed earth storable bipropellant rocket engines to greater than 330 seconds with nitrogen tetroxide and monomothylhydrazine propellants and greater than 335 , seconds with nitrogen tetroxide and hydrazine. Achievement of the NRA goals will significantly benefit NASA interplanetary missions and other government and commercial opportunities by enabling reduced launch weight and/or increased payload. The study also constitutes a crucial stepping stone to future development, such as pump-fed storable engines.

  14. Fermentation of Bioenergy Crops Into Ethanol Using Biological Abatement for Removal of Inhibitors

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Conversion of biomass to fuels or chemicals is hampered by the presence of inhibitory compounds contained in sugar streams derived from lignocellulosic biomass. Biological abatement is a promising method for removing these inhibitors because it neither consumes chemicals nor generates wastes. In t...

  15. NO{sub x} Emission Abatement Technologies

    SciTech Connect

    Goles, R

    1991-10-01

    The Hanford Waste Vitrification Plant (HWVP) will convert Hanford Site high-level liquid defense waste to a solid vitrified (glass) form suitable for final disposal in a geological repository. Future process flow sheet developments may establish a need for a NO, scrubber in the melter off-gas system. Consequently, a technology review has been conducted to identify and compare applicable off-gas processing alternatives should NO, emission abatement be required. Denitrification processes can be separated into two distinct categories, wet or dry, depending upon whether or not NO{sub x} is absorbed into an aqueous solution. The dry methods of removal are generally more efficient (>90%) than wet scrubbing approaches (>60%); however, most dry approaches are applicable only to NO,. Of the dry removal methods, selective catalytic reduction (SCR) using NH3 reductant and a hydrogen zeolite catalyst appears to be the most suitable technology for reducing HWVP NO{sub x} emissions should emission abatement be required. SCR is a relatively simple, well established technology that produces no secondary waste stream and is applicable to a wide range of NO{sub x} concentrations (500 to 30,000 ppm). This technology has been successfully applied to uranium dissolver exhaust streams and has, more recently, been tested and evaluated as the best available control technology for reducing NO, emissions at the Idaho National Engineering Laboratory's waste calciner facility, and at DOE's West Valley Demonstration Project. Unlike dry NO, scrubbing methods, the wet techniques are not specific to NO{sub x}, so they may support the process in more than one way. This is the only major advantage associated with wet technologies. Their disadvantages are that they are not highly efficient at low NO{sub x} concentrations, they produce a secondary waste stream, and they may require complex chemical support to reduce equipment size. Wet scrubbing of HWVP process NO{sub x} emissions is an option that

  16. 24 CFR 35.1325 - Abatement.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... authorized by EPA, or by EPA at 40 CFR 745.227(e), and shall be completed by achieving clearance in... accordance with § 35.1355. Abatement of an intact, factory-applied prime coating on metal surfaces is...

  17. 24 CFR 35.1325 - Abatement.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... authorized by EPA, or by EPA at 40 CFR 745.227(e), and shall be completed by achieving clearance in... accordance with § 35.1355. Abatement of an intact, factory-applied prime coating on metal surfaces is...

  18. Interaction of pollution abatement with world dynamics

    NASA Technical Reports Server (NTRS)

    Smith, G. L.

    1973-01-01

    The world dynamics model of Jay W. Forrester was modified to account for pollution abatement. In the modified model, it is assumed that as pollution increases, efforts are made to control pollution. There is a competition between food supply, material standard of living, and pollution abatement for capital, and time is required for diversion of capital toward pollution abatement. Inclusion of pollution abatement in the model drastically alters the response of the world system for the case in which depletion of natural resources is not considered. Instead of undergoing a pollution catastrophe, all system levels move more or less smoothly toward an equilibrium. A FORTRAN program listing of the modified world dynamics model is included.

  19. 24 CFR 35.1325 - Abatement.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... authorized by EPA, or by EPA at 40 CFR 745.227(e), and shall be completed by achieving clearance in accordance with § 35.1340. If encapsulation or enclosure is used as a method of abatement, ongoing...

  20. 24 CFR 35.1325 - Abatement.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... authorized by EPA, or by EPA at 40 CFR 745.227(e), and shall be completed by achieving clearance in accordance with § 35.1340. If encapsulation or enclosure is used as a method of abatement, ongoing...

  1. 24 CFR 35.1325 - Abatement.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... authorized by EPA, or by EPA at 40 CFR 745.227(e), and shall be completed by achieving clearance in accordance with § 35.1340. If encapsulation or enclosure is used as a method of abatement, ongoing...

  2. Abatements of reduced sulphur compounds, colour, and organic matter from indigo dyeing effluents by electrocoagulation.

    PubMed

    Tünay, Olcay; Simşeker, Merve; Kabdaşli, Isik; Olmez-Hanci, Tugba

    2014-08-01

    In the present study, the treatability of indigo dyeing effluents by the electrocoagulation (EC) process using stainless steel electrodes was experimentally investigated. The samples used were concentrated with main pollutant parameters of chemical oxygen demand (COD) (1000-1100 mg/L), reduced sulphur species (over 2000 mg SO2-(3)/L), and colour (0.12-0.13 1/cm). The study focused on the effect of main operation parameters on the EC process performance in terms of abatement of reduced sulphur compounds as well as decolourization and organic matter reduction. Results indicated that the performance of EC proved to be high providing total oxidation of the reduced sulphur compounds, almost complete decolourization, and COD removal up to 90%. Increasing applied current density from 22.5 to 45 mA/cm2 appreciably improved abatement of the reduced sulphur compounds for Sample I, but a further increase in the applied current density to 67.5 mA/cm2 did not accelerate the conversion rate to sulphate. The process performance was adversely affected by increasing initial concentration of the reduced sulphur compounds. Decolourization and organic matter removal efficiency enhanced with increasing applied current density. The main removal mechanism of the reduced sulphur compounds by EC was explained as conversion to sulphate via oxidation. Conversion rate to sulphate fitted pseudo-first-order kinetics very well. PMID:24956747

  3. Potential Cost-Effective Opportunities for Methane Emission Abatement

    SciTech Connect

    Warner, Ethan; Steinberg, Daniel; Hodson, Elke; Heath, Garvin

    2015-08-01

    The energy sector was responsible for approximately 84% of carbon dioxide equivalent (CO2e) greenhouse gas (GHG) emissions in the U.S. in 2012 (EPA 2014a). Methane is the second most important GHG, contributing 9% of total U.S. CO2e emissions. A large portion of those methane emissions result from energy production and use; the natural gas, coal, and oil industries produce approximately 39% of anthropogenic methane emissions in the U.S. As a result, fossil-fuel systems have been consistently identified as high priority sectors to contribute to U.S. GHG reduction goals (White House 2015). Only two studies have recently attempted to quantify the abatement potential and cost associated with the breadth of opportunities to reduce GHG emissions within natural gas, oil, and coal supply chains in the United States, namely the U.S. Environmental Protection Agency (EPA) (2013a) and ICF (2014). EPA, in its 2013 analysis, estimated the marginal cost of abatement for non-CO2 GHG emissions from the natural gas, oil, and coal supply chains for multiple regions globally, including the United States. Building on this work, ICF International (ICF) (2014) provided an update and re-analysis of the potential opportunities in U.S. natural gas and oil systems. In this report we synthesize these previously published estimates as well as incorporate additional data provided by ICF to provide a comprehensive national analysis of methane abatement opportunities and their associated costs across the natural gas, oil, and coal supply chains. Results are presented as a suite of marginal abatement cost curves (MACCs), which depict the total potential and cost of reducing emissions through different abatement measures. We report results by sector (natural gas, oil, and coal) and by supply chain segment - production, gathering and boosting, processing, transmission and storage, or distribution - to facilitate identification of which sectors and supply chain

  4. The difficulties of abating smoke in late Victorian York

    NASA Astrophysics Data System (ADS)

    Bowler, Catherine; Brimblecombe, Peter

    Historical railway documents and council minutes for the city of York reveal an active interest in abating smoke. As early as the mid-nineteenth century the public became less willing to accept pollution as a necessary part of economic progress. The Sanitary Committee of the council, while diligent in the latter part of the century, seemed unable to use the Public Health Act (1875) effectively. It undertook studies of smoke control devices and their use, but could not identify a workable method of smoke control. Industry, under continual pressure from the Town Clerk's office usually took steps to control smoke emissions. However the improvements in air quality, even when control procedures were adopted by many of the city's major factories, seem disappointing. Weak laws and limited technology hampered a very clear enthusiasm to abate smoke.

  5. Optimal control based seizure abatement using patient derived connectivity

    PubMed Central

    Taylor, Peter N.; Thomas, Jijju; Sinha, Nishant; Dauwels, Justin; Kaiser, Marcus; Thesen, Thomas; Ruths, Justin

    2015-01-01

    Epilepsy is a neurological disorder in which patients have recurrent seizures. Seizures occur in conjunction with abnormal electrical brain activity which can be recorded by the electroencephalogram (EEG). Often, this abnormal brain activity consists of high amplitude regular spike-wave oscillations as opposed to low amplitude irregular oscillations in the non-seizure state. Active brain stimulation has been proposed as a method to terminate seizures prematurely, however, a general and widely-applicable approach to optimal stimulation protocols is still lacking. In this study we use a computational model of epileptic spike-wave dynamics to evaluate the effectiveness of a pseudospectral method to simulated seizure abatement. We incorporate brain connectivity derived from magnetic resonance imaging of a subject with idiopathic generalized epilepsy. We find that the pseudospectral method can successfully generate time-varying stimuli that abate simulated seizures, even when including heterogeneous patient specific brain connectivity. The strength of the stimulus required varies in different brain areas. Our results suggest that seizure abatement, modeled as an optimal control problem and solved with the pseudospectral method, offers an attractive approach to treatment for in vivo stimulation techniques. Further, if optimal brain stimulation protocols are to be experimentally successful, then the heterogeneity of cortical connectivity should be accounted for in the development of those protocols and thus more spatially localized solutions may be preferable. PMID:26089775

  6. Tobacco litter costs and public policy: a framework and methodology for considering the use of fees to offset abatement costs

    PubMed Central

    Peterson, N Andrew; Kiss, Noemi; Ebeid, Omar; Doyle, Alexis S

    2011-01-01

    Objectives Growing concern over the costs, environmental impact and safety of tobacco product litter (TPL) has prompted states and cities to undertake a variety of policy initiatives, of which litter abatement fees are part. The present work describes a framework and methodology for calculating TPL costs and abatement fees. Methods Abatement is associated with four categories of costs: (1) mechanical and manual abatement from streets, sidewalks and public places, (2) mechanical and manual abatement from storm water and sewer treatment systems, (3) the costs associated with harm to the ecosystem and harm to industries dependent on clean and healthy ecosystems, and (4) the costs associated with direct harm to human health. The experiences of the City of San Francisco's recently proposed tobacco litter abatement fee serve as a case study. Results City and municipal TPL costs are incurred through manual and mechanical clean-up of surfaces and catchment areas. According to some studies, public litter abatement costs to US cities range from US$3 million to US$16 million. TPL typically comprises between 22% and 36% of all visible litter, implying that total public TPL direct abatement costs range from about US$0.5 million to US$6 million for a city the size of San Francisco. The costs of mitigating the negative externalities of TPL in a city the size of San Francisco can be offset by implementing a fee of approximately US$0.20 per pack. Conclusions Tobacco litter abatement costs to cities can be substantial, even when the costs of potential environmental pollution and tourism effects are excluded. One public policy option to address tobacco litter is levying of fees on cigarettes sold. The methodology described here for calculating TPL costs and abatement fees may be useful to state and local authorities who are considering adoption of this policy initiative. PMID:21504923

  7. Synthetic waste chemical mechanism studies

    SciTech Connect

    Ashby, E.C.; Annis, A.; Barefield, E.K.

    1994-10-01

    This research involved three main tasks: Kinetic studies of gas evolution and metal complexant decomposition in simulated waste media (SWM); Product identification from metal complexant decomposition in SWM; and Determination of the pathway by which N{sub 2}O, N{sub 2}, and NH{sub 3} are formed in SWM. Results are given on these 3 tasks under the following subtitles: 1. Kinetic studies--Reactions of HEDTA in SWM at different temperatures; Determination of the activation energies for gas formation in HEDTA decomposition under argon; Kinetics and mechanism of thermal degradation of glycolate in SWM; A possible explanation for the temperature dependence of gaseous product ratios for reactions of HEDTA and glycolate; Stoichiometry and kinetics of decomposition of nitrosamines; and Factors affecting the reactions of HEDTA, EDTA, and related compounds in SWM; 2. Product identification--Identification of HEDTA degradation products using {sup 13}C NMR spectroscopy; Identification of irradiated HEDTA degradation products using NMR; Degradation of model systems in SWM; and Role of Al in degradation of organic complexants; 3. Source of gases--Reactions in SY1-SIM-91B mixtures utilizing N-15 labelled reagents; Decomposition of nitrous oxide; Mechanistic pathways for formation of gases containing nitrogen from nitrite; and A redox analysis of HEDTA decomposition--How much ammonia might be formed?

  8. 23 CFR 772.13 - Analysis of noise abatement.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... standard and in conformance with the provisions of 40 CFR 1506.5(c) and 23 CFR 636.109. (j) Third party... PROCEDURES FOR ABATEMENT OF HIGHWAY TRAFFIC NOISE AND CONSTRUCTION NOISE § 772.13 Analysis of noise abatement. (a) When traffic noise impacts are identified, noise abatement shall be considered and evaluated...

  9. 23 CFR 772.13 - Analysis of noise abatement.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 23 Highways 1 2012-04-01 2012-04-01 false Analysis of noise abatement. 772.13 Section 772.13 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RIGHT-OF-WAY AND ENVIRONMENT PROCEDURES FOR ABATEMENT OF HIGHWAY TRAFFIC NOISE AND CONSTRUCTION NOISE § 772.13 Analysis of noise abatement. (a) When traffic noise impacts are...

  10. 23 CFR 772.13 - Analysis of noise abatement.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 23 Highways 1 2013-04-01 2013-04-01 false Analysis of noise abatement. 772.13 Section 772.13 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RIGHT-OF-WAY AND ENVIRONMENT PROCEDURES FOR ABATEMENT OF HIGHWAY TRAFFIC NOISE AND CONSTRUCTION NOISE § 772.13 Analysis of noise abatement. (a) When traffic noise impacts are...

  11. 10 CFR 851.22 - Hazard prevention and abatement.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Hazard prevention and abatement. 851.22 Section 851.22 Energy DEPARTMENT OF ENERGY WORKER SAFETY AND HEALTH PROGRAM Specific Program Requirements § 851.22 Hazard prevention and abatement. (a) Contractors must establish and implement a hazard prevention and abatement process to ensure that all identified...

  12. POLLUTION ABATEMENT COSTS AND EXPENDITURES SURVEY

    EPA Science Inventory

    The Pollution Abatement Costs and Expenditures (PACE) Survey is a Census Bureau product funded via a cooperative agreement with EPA. PACE data was collected by Census from 1974-1996 (except 1987) and 1999. The survey consists of approximately 20,000 manufacturing facilities in ...

  13. 29 CFR 4207.3 - Abatement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... section, as appropriate. If a bond or escrow has been provided to the plan under § 4207.4, the plan sponsor shall send a copy of the notice to the bonding or escrow agent. (c) Effects of abatement. If the... applicable; (3) Any bonds furnished under § 4207.4 shall be cancelled and any amounts held in escrow...

  14. 29 CFR 4207.3 - Abatement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... section, as appropriate. If a bond or escrow has been provided to the plan under § 4207.4, the plan sponsor shall send a copy of the notice to the bonding or escrow agent. (c) Effects of abatement. If the... applicable; (3) Any bonds furnished under § 4207.4 shall be cancelled and any amounts held in escrow...

  15. Hanford Site Asbestos Abatement Plan. Revision 1

    SciTech Connect

    Mewes, B.S.

    1993-09-01

    The Hanford Site Asbestos Abatement Plan (Plan) lists priorities for asbestos abatement activities to be conducted in Hanford Site facilities. The Plan is based on asbestos assessment information gathered in fiscal year 1989 that evaluated all Hanford Site facilities for the presence and condition of asbestos. Of those facilities evaluated, 414 contain asbestos-containing materials and are classified according to the potential risk of asbestos exposure to building personnel. The Plan requires that asbestos condition update reports be prepared for all affected facilities. The reporting is completed by the asbestos coordinator for each of the 414 affected facilities and transmitted to the Plan manager annually. The Plan manager uses this information to reprioritize future project lists. Currently, five facilities are determined to be Class Al, indicating a high potential for asbestos exposure. Class Al and B1 facilities are the highest priority for asbestos abatement. Abatement of the Class A1 and Bl facilities is scheduled through fiscal year 1997. Removal of asbestos in B1 facilities will reduce the risk for further Class ``A`` conditions to arise.

  16. Cost effectiveness of abatement options for emissions control in Egyptian iron foundries

    SciTech Connect

    Rabah, M.A. . Industrial Wastes Lab.)

    1999-01-01

    This study focuses on an evaluation of the cost effectiveness of abatement options for controlling emissions in existing iron foundries in Egypt. It is expected that such a study will enable decision by identifying concrete measures for abating total solid emissions (TSP). The structure of iron foundries in the country have been surveyed and the variant types of furnaces, the TSP emission level without any abatement options and data of the annual turnover of these foundries have been obtained. Possible market based instruments (MBI) options that might encourage these firms to seek the most efficient control measures have also been examined. Different abatement options such as updating burner design, switching heavy fuel oil to kerosene or natural gas, installing cleaning systems and/or updating the process technology were tested in terms of emission level and the overall turnover. The effect of installing different cleaning systems such as wet scrubbers and filter bags on the running cost of abating TSP was also investigated. Results obtained reveal that crucible (CrF) and short rotary (SRF) furnaces are the most numerous types of plants in Egypt. The concentration of TSP emissions exceeds the standards as specified in Law. Poor quality scrap input adversely affects the operation of the furnace, and impairs product quality and causes excessive TSP emissions. TSP emissions per ton of cast iron produced are relatively low for induction furnaces (EIFs), and very high in the dirtier technologies, particularly CrF and SRF. Cost analysis shows that the cost of abating one ton of TSP emitted amounts to 3000--5000 L.E and this cost represents a high percentage of turnover to plants abating emissions.

  17. Chemical Case Studies: Science-Society "Bonding."

    ERIC Educational Resources Information Center

    Hofstein, Avi; Nae, Nehemia

    1981-01-01

    Describes a unit designed to illustrate the "science-society-technology connection," in which three case studies of the chemical industry in Israel are presented to high school chemistry students. Chosen for the unit are case studies on copper production in Timna, on plastics, and on life from the Dead Sea. (CS)

  18. Effects of dietary ABATE? on reproductive success, duckling survival, behavior, and clinical pathology in game-farm mallards

    USGS Publications Warehouse

    Franson, J.C.; Spann, J.W.; Heinz, G.H.; Bunck, C.M.; Lamont, T.

    1983-01-01

    Forty-four pairs of game-farm mallards (Anas platyrhynchos) were fed ABATE? E (temephos) to yield 0, 1, or 10 ppm ABATE? beginning before the initiation of lay, and terminating when ducklings were 21 days of age. The mean interval between eggs laid was greater for hens fed 10 ppm ABATE? than for controls. Clutch size, fertility, hatchability, nest attentiveness of incubating hens, and avoidance behavior of ducklings were not significantly affected by ABATE? ingestion. The percentage survival of ducklings to 21 days of age was significantly lower in both treated groups than in controls, but brain acetylcholinesterase (AChE) activity was not inhibited in young which died before termination of the study. In 21-day-old ducklings, aspartate aminotransferase (AST) activity increased and plasma nonspecific cholinesterase (ChE) activity was inhibited by about 20% in both treatment groups, but there were no significant differences in brain AChE or plasma alanine aminotransferase (ALT) activities, or plasma uric acid concentration. Clinical chemistry values of adults were not affected. No ABATE?, ABATE? sulfoxide, or ABATE? sulfone residues were found in eggs or tissue samples.

  19. The public health relevance of air pollution abatement.

    PubMed

    Künzli, N

    2002-07-01

    Assuming a causal relationship between current levels of air pollution and morbidity/mortality, it is crucial to estimate the public health relevance of the problem. The derivation of air pollution attributable cases faces inherent uncertainties and requires influential assumptions. Based on the results of the trinational impact assessment study of Austria, France, and Switzerland, where prudent estimates of the air pollution attributable cases (mortality, chronic bronchitis incidence, hospital admissions, acute bronchitis among children, restricted activity days, asthma attacks) have been made, influential uncertainties are quantified in this review. The public health impact of smoking, environmental tobacco smoke, and air pollution on the prevalence of chronic cough/phlegm are outlined. Despite all methodological caveats, impact assessment studies clearly suggest that public health largely benefits from better air quality. The studies are selective underestimates as they are strongly driven by mortality, but do not include full quantification of the impact on morbidity and their consequences on quality of life among the diseased and the caregivers. Air pollution abatement strategies are usually political in nature, targeting at polities, regulation and technology in mobile or stationary sources rather than at individuals. It is of note that key clean air strategies converge into abatement of climate change. In general, energy consumption is very closely related to both air pollution and greenhouse gases. The dominant causes of both problems are the excessive and inefficient combustion of fossil fuel. Thus, for many policy options, the benefit of air pollution abatement will go far beyond what prudent health-impact assessments may derive. From a climate change and air pollution perspective, improved energy efficiency and a strong and decisive departure from the "fossil fuel" combustion society is a science-based must. Health professionals must raise their voices

  20. Abatement costs of soil conservation in China's Loess Plateau: balancing income with conservation in an agricultural system.

    PubMed

    Hou, Lingling; Hoag, Dana L K; Keske, Catherine M H

    2015-02-01

    This study proposes the use of marginal abatement cost curves to calculate environmental damages of agricultural systems in China's Loess Plateau. Total system costs and revenues, management characteristics and pollution attributes are imputed into a directional output distance function, which is then used to determine shadow prices and abatement cost curves for soil and nitrogen loss. Marginal abatement costs curves are an effective way to compare economic and conservation tradeoffs when field-specific data are scarce. The results show that sustainable agricultural practices can balance soil conservation and agricultural production; land need not be retired, as is current policy. PMID:25463565

  1. Chemical Erosion Studies of Lithiated Graphite

    NASA Astrophysics Data System (ADS)

    Raman, Priya; Surla, Vijay; Burns, David; Ruzic, David

    2010-11-01

    Lithium evaporation treatments in the National Spherical Torus Experiment (NSTX) have shown dramatic improvements in plasma performance increasing the viability of lithium as Plasma facing Component (PFC) material. In order to understand the complex system of lithiated ATJ graphite, chemical erosion measurements of plain and lithiated ATJ graphite are conducted in the newly built RF plasma facility. A differential pumping scheme is employed and a Residual Gas Analyzer is used for chemical erosion measurements. Target is mounted on a substrate heater (0-500C) and it is connected to a biasing circuitry to allow for temperature dependent studies and energy dependent measurements. To study the effect of lithium on chemical erosion, lithium is evaporated in-situ onto ATJ graphite. The dominant chemical erosion products are known to be CD4 and C2D2. The challenges in measuring C2D2, as it interferes with N2 and CO peaks, are presented. It was found that lithium treatments have suppressed the CD4 signal, and the effect of lithium on other peaks is presented. The effect of temperature on chemical erosion is also investigated and it was found that temperature increases the erosion of graphite.

  2. Abating exhaust noises in jet engines

    NASA Technical Reports Server (NTRS)

    Schwartz, I. R. (Inventor)

    1974-01-01

    A noise abating improvement for jet engines including turbojets, turbofans, turboprops, ramjets, scramjets, and hybrid jets is introduced. A provision is made for an apparatus in the primary and/or secondary flow streams of the engines; the apparatus imparts to the exhaust gases a component rotation or swirl about the engine's longitudinal axis. The rotary component in the exhaust gases causes a substantial suppression of sound energy build up normally produced by an axial flow exhaust system.

  3. Chemically modified electrodes and related solution studies

    SciTech Connect

    Elliott, C.M.

    1990-01-01

    This report briefly discusses work done in the following areas of chemically modified electrodes: Spectroscopic studies of the modes of interactions of pyridine containing ligands with metal surfaces; attempted synthesis of gem-dihalide containing polymers for attachment of Mo{sub 2}S{sub 4} clusters; Synthesis of oxo-ruthenium dimer complexes as catalysts for H{sub 2} oxidation; and, studies of porphyrin based polymers which catalyze the oxidation (oxygenation) of olefins and benzylic carbons. (JDL)

  4. Relative toxicity of decamethrin, chlorphoxim and temephos (abate) to simulium larvae.

    PubMed

    Muirhead-Thomson, R C

    1981-09-01

    Tolerance levels Simulium larvae (S. ornatum and S. equinum) to chlorphoxim and decamethrin, relative to those with Abate, were determined in rapid through-flow laboratory test vessels; a 1-hour exposure followed by 24-hour mortality observations being the standard of comparison of the three chemicals. In addition, a further comparison between chlorphoxim and Abate was made on the basis of a 15-minute exposure in a miniature simulated stream, with the same mortality criteria. On the basis of LC95/1-hour data the results showed that decamethrin was approximately 4 times as lethal as chlorphoxim, and approximately 20 times more than Abate. On the basis of a 15-minute exposure, chlorphoxim was found to be even more toxic than Abate--approximately 10 times more--than with the 1-hour exposure--viz 5 times more. Concentration/mortality curves indicate that with both the organophosphorus larvicides there is a critical zone where mortality increases sharply with increase in concentration of toxinant. With decamethrin, there is a more uniform rate of increase in mortality with increasing concentration, these differences being illustrated by comparison at both LC50 and LC95 levels. These findings are discussed firstly, in relation to other laboratory test methods in use, and secondly with reference to the scarcity of comparable laboratory data for Simulium damnosum in the Onchosceriasis Control Programme (OCP) in the Volta River basin area of West Africa. PMID:6179275

  5. PM sources in a highly industrialised area in the process of implementing PM abatement technology. Quantification and evolution.

    PubMed

    Cruz Minguillón, María; Querol, Xavier; Alastuey, Andrés; Monfort, Eliseo; Vicente Miró, José

    2007-10-01

    Principal component analysis (PCA) coupled with a multilinear regression analysis (MLRA) was applied to PM(10) speciation data series (2002-2005) from four sampling sites in a highly industrialised area (ceramic production) in the process of implementing emission abatement technology. Five common factors with similar chemical profiles were identified at all the sites: mineral, regional background (influenced by the industrial estate located on the coast: an oil refinery and a power plant), sea spray, industrial 1 (manufacture and use of glaze components, including frit fusion) and road traffic. The contribution of the regional background differs slightly from site to site. The mineral factor, attributed to the sum of several sources (mainly the ceramic industry, but also with minor contributions from soil resuspension and African dust outbreaks) contributes between 9 and 11 microg m(-3) at all the sites. Source industrial 1 entails an increase in PM(10) levels between 4 and 5 microg m(-3) at the urban sites and 2 microg m(-3) at the suburban background site. However, after 2004, this source contributed less than 2 microg m(-3) at most sites, whereas the remaining sources did not show an upward or downward trend along the study period. This gradual decrease in the contribution of source industrial 1 coincides with the implementation of PM abatement technology in the frit fusion kilns of the area. This relationship enables us to assess the efficiency of the implementation of environmental technologies in terms of their impact on air quality. PMID:17909641

  6. MICROBIAL ECOLOGY OF POLLUTION ABATEMENT

    EPA Science Inventory

    My career started with Cliff Dahm at the University of New Mexico. The western United States had been experiencing a new “gold rush” using cyanide to mine previously unextractable, low-grade ore and we studied the potential to stimulate native cyanide-degrading micro...

  7. Studying chemical reactivity in a virtual environment.

    PubMed

    Haag, Moritz P; Reiher, Markus

    2014-01-01

    Chemical reactivity of a set of reactants is determined by its potential (electronic) energy (hyper)surface. The high dimensionality of this surface renders it difficult to efficiently explore reactivity in a large reactive system. Exhaustive sampling techniques and search algorithms are not straightforward to employ as it is not clear which explored path will eventually produce the minimum energy path of a reaction passing through a transition structure. Here, the chemist's intuition would be of invaluable help, but it cannot be easily exploited because (1) no intuitive and direct tool for the scientist to manipulate molecular structures is currently available and because (2) quantum chemical calculations are inherently expensive in terms of computational effort. In this work, we elaborate on how the chemist can be reintroduced into the exploratory process within a virtual environment that provides immediate feedback and intuitive tools to manipulate a reactive system. We work out in detail how this immersion should take place. We provide an analysis of modern semi-empirical methods which already today are candidates for the interactive study of chemical reactivity. Implications of manual structure manipulations for their physical meaning and chemical relevance are carefully analysed in order to provide sound theoretical foundations for the interpretation of the interactive reactivity exploration. PMID:25340884

  8. Quantum chemical study of methane oxidation species

    NASA Technical Reports Server (NTRS)

    Jackels, Charles F.

    1993-01-01

    The research funded by this project has focused on quantum chemical investigations of molecular species thought to be important in the chemistry of the earth's upper and lower atmospheres. The body of this report contains brief discussions of the results of the several phases of this investigation. In many instances these results have been presented at scientific meetings and/or published in refereed journals. Those bibliographic references are given. In addition to the study of specific chemical systems, there were several phases during the course of this investigation where much of the effort went into the development and modification of computer codes necessary to carry out these calculations on the wide range of computer equipment used during this study. This type of code maintenance and development work did not generally result in publications and presentations, but a brief review is given.

  9. Study of chemical and radiation induced carcinogenesis

    SciTech Connect

    Chmura, A.

    1995-11-01

    The study of chemical and radiation induced carcinogenesis has up to now based many of its results on the detection of genetic aberrations using the fluorescent in situ hybridization (FISH) technique. FISH is time consuming and this tends to hinder its use for looking at large numbers of samples. We are currently developing new technological advances which will increase the speed, clarity and functionality of the FISH technique. These advances include multi-labeled probes, amplification techniques, and separation techniques.

  10. Olive oil mill wastewaters pollution abatement by physical treatments and biodegradation with Phanerochaetae chrysosporium.

    PubMed

    Mebirouk, M; Sbai, L; Lopez, M; Gonzalez, J

    2006-12-01

    This paper discusses decolorization and chemical oxygen demand (COD) abatement in olive mill wastewaters (OMW) by Phanerochaetae chrysosporium grown in static, suspended and immobilised cultures. When P chrysosporium is used in cultures, no decolorization of crude OMW is observed. Decolorization occurs only after removal of polyphenols by adsorption on wood sawdust, which allows for removal of 39% of polyphenols. The use of High lignin peroxides (Lip) producing medium, yields the highest OMW decolorization and COD removal efficiencies. The use of P. chrysosporium immobilized on polyurethane foam leads to significant abatements of OMW polluting characteristics. In fact, chemical oxygen demand (COD), Biological oxygen demand (BOD5) and polyphenols contents are significantly reduced. In addition, a significant effluent decolorization is obvious. PMID:17285940

  11. Abating environmentally harmful waste gases

    NASA Astrophysics Data System (ADS)

    Sridhar, S.; Sichen, Du; Pal, U. B.; Seetharaman, S.

    2002-05-01

    A gas-purification method, based on the condensation of nitrogen, sulfur, and carbon-containing environmentally hazardous gases produced from industrial processes, is proposed in this article. The method, which utilizes the cooling capacity of waste nitrogen in the oxygen plant to condense the hazardous gases, is capable of removing hazardous impurities up to 99.98%. Theoretical calculations underlying the condensation process are presented employing gases produced in a blast furnace and coke oven in an integrated steel plant. The cooling power required for the condensation process is calculated using the waste nitrogen generated from an oxygen plant that generates captive oxygen for the steel plant. Design modifications that need to be made to the oxygen plant in order to utilize the cooling power of the waste nitrogen gas are also presented. As a case study, the advantages of the method are illustrated with purification of coke-oven gas. The economic impact and the investment aspects are also discussed.

  12. Kinetic studies of elementary chemical reactions

    SciTech Connect

    Durant, J.L. Jr.

    1993-12-01

    This program concerning kinetic studies of elementary chemical reactions is presently focussed on understanding reactions of NH{sub x} species. To reach this goal, the author is pursuing experimental studies of reaction rate coefficients and product branching fractions as well as using electronic structure calculations to calculate transition state properties and reaction rate calculations to relate these properties to predicted kinetic behavior. The synergy existing between the experimental and theoretical studies allow one to gain a deeper insight into more complex elementary reactions.

  13. Theoretical studies of chemical reaction dynamics

    SciTech Connect

    Schatz, G.C.

    1993-12-01

    This collaborative program with the Theoretical Chemistry Group at Argonne involves theoretical studies of gas phase chemical reactions and related energy transfer and photodissociation processes. Many of the reactions studied are of direct relevance to combustion; others are selected they provide important examples of special dynamical processes, or are of relevance to experimental measurements. Both classical trajectory and quantum reactive scattering methods are used for these studies, and the types of information determined range from thermal rate constants to state to state differential cross sections.

  14. Comparative results of 327 chemical carcinogenicity studies.

    PubMed Central

    Haseman, J K; Huff, J E; Zeiger, E; McConnell, E E

    1987-01-01

    The National Cancer Institute (NCI) and the National Toxicology Program (NTP) have carried out a number of laboratory animal carcinogenicity studies and presented the results of these experiments in a series of Technical Reports. This paper tabulates the results of the 327 NCI/NTP studies carried out to date on 308 distinct chemicals, and discusses certain issues relevant to the evaluation of carcinogenicity in these experiments. This compilation of results from NCI/NTP carcinogenicity experiments provides a large database that can be used to study structure-activity correlations, interspecies concordance, and associations between laboratory animal carcinogenicity and other toxicological effects. PMID:3691430

  15. Emission abatement system utilizing particulate traps

    DOEpatents

    Bromberg, Leslie; Cohn, Daniel R.; Rabinovich, Alexander

    2004-04-13

    Emission abatement system. The system includes a source of emissions and a catalyst for receiving the emissions. Suitable catalysts are absorber catalysts and selective catalytic reduction catalysts. A plasma fuel converter generates a reducing gas from a fuel source and is connected to deliver the reducing gas into contact with the absorber catalyst for regenerating the catalyst. A preferred reducing gas is a hydrogen rich gas and a preferred plasma fuel converter is a plasmatron. It is also preferred that the absorber catalyst be adapted for absorbing NO.sub.x.

  16. [Studies on chemical constituents from Psychotria straminea].

    PubMed

    Fu, Yan-hui; Huang, Li-gang; Wang, Xiao-cui; Li, Xiao-bao; Li, Ke-kai; Wu, Shui-ling; Liu, Yan-ping

    2015-06-01

    The chemical consituents from Psychotria straminea were separated and purified by column chromatographies on silica gel, Sephadex LH-20, ODS and RP-HPLC. The strictures of the isolated compounds were identified on the basis of physicochemical properties and spectroscopic analysis, as well as comparisons with the data in literature. Sixteen compounds were isolated and elucidated as tectochrysin (1), apigenin (2), kaempferol (3), luteolin (4), diosmetin (5), quercetin (6), kaempferol-4'-O-methylether (7), rhamnetin (8), 7-hydroxycoumarin (9), 7-methoxycoumarin (10), scopoletin (11), lupeol (12), 30-oxo-lupeol (13), lupenyl acetate (14), α-amyrin (15), and ursolic acid (16). This is the first study on the chemical composition of P. Straminea, and all compounds were isolated from P. straminea for the first time. In addition to compounds 6 and 9, the other compounds were isolated from the genus Psychotria for the first time. PMID:26552170

  17. [Study on chemical constituents of Picrasma quassioides].

    PubMed

    Zhu, Chenchen; Deng, Guihua; Lin, Chaozhan

    2011-04-01

    To study the chemical constituents of Picrasma quassioides. The chemical constituents were isolated and purified by chromatographic methods over Sephadex LH-20 and silica gel column, and structurally elucidated by spectral analysis, including UV, IR, MS, 1H-NMR, 13C-NMR. Fourteen compounds were obtained and identified as trifolirhizin(1), maackiain(2), 3', 7-dihydroxy-4'-methoxylisoflavone(3), umbelliferone(4), emodin(5), nigakilactone F(6), picrasin B(7),picraqualide B (8),4-methoxy-5-hydroxycanthin-6-one(9), 4,5-dimethoxycanthin-6-one (10),5-methoxycanthin-6-one(11), 11-hydroxycanthin-6-one(12) , 1-methoxycarbonyl-beta-carboline(13), 1-hydroxymethyl-beta-carboline(14). Compounds 1-5 are reported from the first time for the genus Pricrasma. PMID:21761728

  18. High Resolution Chemical Study of ALH84001

    NASA Technical Reports Server (NTRS)

    Conrad, Pamela G.; Douglas, Susanne; Kuhlman, Kimberly R.

    2001-01-01

    We have studied the chemistry of a sample of the SNC meteorite ALH84001 using an environmental scanning electron microscope (ESEM) with an energy dispersive chemical analytical detector and a focused ion beam secondary ion mass spectrometer (FIB-SIMS). Here we present the chemical data, both spectra and images, from two techniques that do not require sample preparation with a conductive coating, thus eliminating the possibility of preparation-induced textural artifacts. The FIB-SIMS instrument includes a column optimized for SEM with a quadrupole type mass spectrometer. Its spatial and spectral resolution are 20 nm and 0.4 AMU, respectively. The spatial resolution of the ESEM for chemical analysis is about 100 nm. Limits of detection for both instruments are mass dependent. Both the ESEM and the FIB-SIMS instrument revealed contrasting surficial features; crumbled, weathered appearance of the matrix in some regions as well as a rather ubiquitous presence of euhedral halite crystals, often associated with cracks or holes in the surface of the rock. Other halogen elements present in the vicinity of the NaCl crystals include K and Br. In this report, elemental inventories are shown as mass spectra and as X-ray maps.

  19. Managing lead-based paint abatement wastes

    SciTech Connect

    Steele, N.L.C.

    1994-12-31

    Renovation, remodeling, demolition, and surface preparation for painting, in addition to specified lead abatement, are all activities that have the potential to produce hazardous wastes if a property was painted with lead-based paint. Lead-based paint was used on residential structures until 1978, when most residential uses were banned by the Consumer Products Safety Council. Prior to the 1950s, paints for residential uses may have contained up to 50% lead by weight. Today, commercial and military paints may still contain lead and can be used on non-residential structures. The lead content of residential paints is limited to 0.06% lead (by weight) in the dried film. This paper provides an overview of some of the information needed to properly manage lead-based paint abatement wastes. The issues covered in this paper include waste classification, generator status, treatment, and land disposal restrictions. The author assumes that the reader is familiar with the provision of the Health and Safety Code and the California Code of Regulations that pertain to generation and management of hazardous wastes. Citations provided herein do not constitute an exhaustive list of all the regulations with which a generator of hazardous waste must comply.

  20. Spectroscopic and quantum chemical studies of isocytosine

    SciTech Connect

    Tulub, A.A.; Semenov, S.G.; Stetsenko, A.I.; Yudovich, E.E.

    1988-07-01

    The methods of electronic and vibrational (IR) spectroscopy were used to study the spectral properties of isocytosine in H/sub 2/O, D/sub 2/O, chloroform, and hexane in a wide concentration interval. Quantum chemical calculations of tautomeric forms and dimers of isocytosine were carried out. The bands of the calculated and experimental spectra were assigned. The results of the quantum calculations were compared with the experimental data. The spectral bands were classified according to the type of tautomer or dimer to which they belong.

  1. 29 CFR 4207.10 - Plan rules for abatement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 9 2013-07-01 2013-07-01 false Plan rules for abatement. 4207.10 Section 4207.10 Labor Regulations Relating to Labor (Continued) PENSION BENEFIT GUARANTY CORPORATION WITHDRAWAL LIABILITY FOR MULTIEMPLOYER PLANS REDUCTION OR WAIVER OF COMPLETE WITHDRAWAL LIABILITY § 4207.10 Plan rules for abatement. (a) General rule. Subject to...

  2. 47 CFR 22.971 - Obligation to abate unacceptable interference.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Obligation to abate unacceptable interference. 22.971 Section 22.971 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.971 Obligation to abate unacceptable interference. (a) Strict...

  3. 47 CFR 22.878 - Obligation to abate unacceptable interference.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Obligation to abate unacceptable interference. 22.878 Section 22.878 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES PUBLIC MOBILE SERVICES Air-Ground Radiotelephone Service Commercial Aviation Air-Ground Systems § 22.878 Obligation to abate...

  4. 30 CFR 722.13 - Failure to abate.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Failure to abate. 722.13 Section 722.13 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR INITIAL PROGRAM REGULATIONS ENFORCEMENT PROCEDURES § 722.13 Failure to abate. An authorized representative of the...

  5. 30 CFR 722.13 - Failure to abate.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Failure to abate. 722.13 Section 722.13 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR INITIAL PROGRAM REGULATIONS ENFORCEMENT PROCEDURES § 722.13 Failure to abate. An authorized representative of the...

  6. 30 CFR 722.13 - Failure to abate.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Failure to abate. 722.13 Section 722.13 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR INITIAL PROGRAM REGULATIONS ENFORCEMENT PROCEDURES § 722.13 Failure to abate. An authorized representative of the...

  7. 30 CFR 722.13 - Failure to abate.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Failure to abate. 722.13 Section 722.13 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR INITIAL PROGRAM REGULATIONS ENFORCEMENT PROCEDURES § 722.13 Failure to abate. An authorized representative of the...

  8. 76 FR 67650 - Migratory Bird Permits; Abatement Regulations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-02

    ... for a specific permit authorizing the use of raptors in abatement activities (76 FR 39368). The... the advance notice of proposed rulemaking, please refer to that document at 76 FR 39368 (July 6, 2011... Fish and Wildlife Service 50 CFR Part 21 RIN 1018-AW75 Migratory Bird Permits; Abatement...

  9. VISUAL INSPECTION AND AHERA CLEARANCE AT ASBESTOS ABATEMENT SITES

    EPA Science Inventory

    Asbestos abatement carried out in schools is subject to regulations under the Asbestos Hazard Emergency Response Act (AHERA) of 1986. The AHERA rule (40 CFR Part 763) specifies a bifactorial process for determining when an asbestos abatement site is clean enough for the primary ...

  10. VISUAL INSPECTION AND AHERA CLEARANCE AT ASBESTOS-ABATEMENT SITES

    EPA Science Inventory

    Asbestos abatement carried out in schools is subject to regulations under the Asbestos Hazard Emergency Response Act (AHERA) of 1986. he AHERA rule (40 CFR Part 763) specifies a bifactorial process for determining when an asbestos abatement site is clean enough for the primary co...

  11. 30 CFR 722.13 - Failure to abate.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 3 2012-07-01 2012-07-01 false Failure to abate. 722.13 Section 722.13 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR INITIAL PROGRAM REGULATIONS ENFORCEMENT PROCEDURES § 722.13 Failure to abate. An authorized representative of the...

  12. WET/DRY COOLING SYSTEMS FOR FOSSIL-FUELED POWER PLANTS: WATER CONSERVATION AND PLUME ABATEMENT

    EPA Science Inventory

    The report gives results of a study of technical and economic feasibilities of wet/dry cooling towers for water conservation and vapor plume abatement. Results of cost optimizations of wet/dry cooling for 1000-MWe fossil-fueled power plants are presented. Five sites in the wester...

  13. IN-PLACE PERFORMANCE EVALUATION OF HEPA-FILTRATION SYSTEMS AT ASBESTOS-ABATEMENT SITES

    EPA Science Inventory

    This study was conducted to assess the in-place performance of high efficiency particulate air (HEPA) filtration systems at asbestos-abatement siteS in New Jersey to determine each systems particle-removal efficiency. n air-generated dioctyl phthalate aerosol was used to challeng...

  14. Chemical carcinogenesis studies in nonhuman primates

    PubMed Central

    Takayama, Shozo; Thorgeirsson, Unnur P.; Adamson, Richard H.

    2008-01-01

    This review covers chemical carcinogenesis studies in nonhuman primates performed by the National Cancer Institute, USA, to provide hitherto unavailable information on their susceptibility to compounds producing carcinogenic effects in rodents. From autopsy records of 401 breeders and untreated controls, incidences of spontaneous malignant tumors were found to be relatively low in cynomolgus (1.9%) and rhesus monkeys (3.8%), but higher in African green monkeys (8%). Various chemical compounds, and in particular 6 antineoplastic agents, 13 food-related compounds including additives and contaminants, 1 pesticide, 5 N-nitroso compounds, 3 heterocyclic amines, and 7 “classical” rodent carcinogens, were tested during the 34 years period, generally at doses 10∼40 times the estimated human exposure. Results were inconclusive in many cases but unequivocal carcinogenicity was demonstrated for IQ, procarbazine, methylnitrosourea and diethylnitrosamine. Furthermore, negative findings for saccharine and cyclamate were in line with results in other species. Thus susceptibility to carcinogens is at least partly shared by nonhuman primates and rodents. PMID:18941297

  15. [Laser enhanced chemical reaction studies]. [Progress report

    SciTech Connect

    Not Available

    1992-04-01

    Experimental studies of dynamic molecular processes are described with particular emphasis on the use of a powerful infrared diode laser probe technique developed in our laboratory. This technique allows us to determine the final states of CO{sub 2} (and other molecules) produced by collisions, photofragmentation, or chemical reactions with a spectral resolution of 0.0003 cm{sup {minus}1} and a time resolution of 10{sup {minus}7} sec. Such high spectral resolution provides a detailed picture of the vibrational and rotational states of molecules produced by these dynamic events. We have used this experimental method to probe collisions between hot hydrogen/deuterium atoms and CO{sub 2}, between O({sup 1}D) atoms and CO{sub 2}, to study the final states of DC1 molecules produced as a result of the reactions of hot Cl atoms, and to investigate the dynamics of the reaction between OH and CO molecules. Advances in our techniques over the past two years have allowed us to identify and study more than 200 final rotational states in ten different vibrational levels of CO{sub 2} encompassing all 3 normal modes, many overtones, and combination states of the molecule. We have extended the technique to probe a variety of new molecules such as OCS, N{sub 2}O, DCl, and CS{sub 2}. All of this work is aimed at providing experimental tests for polyatomic molecule potential energy surfaces, chemical transition states in complex systems, and theories of reaction dynamic in molecules with more than 3 atoms.

  16. SMA Hybrid Composites for Dynamic Response Abatement Applications

    NASA Technical Reports Server (NTRS)

    Turner, Travis L.

    2000-01-01

    A recently developed constitutive model and a finite element formulation for predicting the thermomechanical response of Shape Memory Alloy (SMA) hybrid composite (SMAHC) structures is briefly described. Attention is focused on constrained recovery behavior in this study, but the constitutive formulation is also capable of modeling restrained or free recovery. Numerical results are shown for glass/epoxy panel specimens with embedded Nitinol actuators subjected to thermal and acoustic loads. Control of thermal buckling, random response, sonic fatigue, and transmission loss are demonstrated and compared to conventional approaches including addition of conventional composite layers and a constrained layer damping treatment. Embedded SMA actuators are shown to be significantly more effective in dynamic response abatement applications than the conventional approaches and are attractive for combination with other passive and/or active approaches.

  17. Low-thrust chemical rocket engine study

    NASA Technical Reports Server (NTRS)

    Shoji, J. M.

    1981-01-01

    An analytical study evaluating thrust chamber cooling engine cycles and preliminary engine design for low thrust chemical rocket engines for orbit transfer vehicles is described. Oxygen/hydrogen, oxygen/methane, and oxygen/RP-1 engines with thrust levels from 444.8 N to 13345 N, and chamber pressures from 13.8 N/sq cm to 689.5 N/sq cm were evaluated. The physical and thermodynamic properties of the propellant theoretical performance data, and transport properties are documented. The thrust chamber cooling limits for regenerative/radiation and film/radiation cooling are defined and parametric heat transfer data presented. A conceptual evaluation of a number of engine cycles was performed and a 2224.1 N oxygen/hydrogen engine cycle configuration and a 2224.1 N oxygen/methane configuration chosen for preliminary engine design. Updated parametric engine data, engine design drawings, and an assessment of technology required are presented.

  18. Chemical warfare, past and future. Study project

    SciTech Connect

    Tzihor, A.

    1992-05-15

    World War I was arena for the first use of chemical warfare. The enormous tactical success brought about by this first time use of chemical weapons caused the continued development of more sophisticated tactics and weapons in this category of unconventional warfare. This phenomenon has carried through to today. However, at present, because of technological developments, the global economic situation, and political factors, coupled with the inability of the western world to control the proliferation of chemical weapons, a situation weapon of mass destruction. Recent use by Iraq against Kurdish civilian indicates that chemical warfare is no longer limited to the battlefield. The western nations have a need to understand the risk. This paper conducts an analysis of past lessons and the factors which will affect the use of chemical warfare in the future. From this analysis, the paper reaches conclusions concerning the significant threat chemical weapons pose for the entire world in the not too distant future.

  19. 40 CFR 792.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 33 2013-07-01 2013-07-01 false Physical and chemical characterization... A Study § 792.135 Physical and chemical characterization studies. (a) All provisions of the GLPs shall apply to physical and chemical characterization studies designed to determine...

  20. 40 CFR 792.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 32 2011-07-01 2011-07-01 false Physical and chemical characterization... A Study § 792.135 Physical and chemical characterization studies. (a) All provisions of the GLPs shall apply to physical and chemical characterization studies designed to determine...

  1. 40 CFR 792.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 32 2014-07-01 2014-07-01 false Physical and chemical characterization... A Study § 792.135 Physical and chemical characterization studies. (a) All provisions of the GLPs shall apply to physical and chemical characterization studies designed to determine...

  2. 40 CFR 792.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 31 2010-07-01 2010-07-01 true Physical and chemical characterization... A Study § 792.135 Physical and chemical characterization studies. (a) All provisions of the GLPs shall apply to physical and chemical characterization studies designed to determine...

  3. 40 CFR 792.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 33 2012-07-01 2012-07-01 false Physical and chemical characterization... A Study § 792.135 Physical and chemical characterization studies. (a) All provisions of the GLPs shall apply to physical and chemical characterization studies designed to determine...

  4. OXIDATION SCREENING STUDIES FOR CCL ORGANIC CHEMICALS

    EPA Science Inventory

    The understanding of the oxidation reactions associated with the Agency's Contaminant Candidate List (CCL)chemicals is important from several perspectives. Chemicals are added to the CCL because of their potential to negatively impact human health. The removal/control of that che...

  5. Quantum chemical studies of estrogenic compounds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Quantum chemical methods are potent tools to provide information on the chemical structure and electronic properties of organic molecules. Modern computational chemistry methods have provided a great deal of insight into the binding of estrogenic compounds to estrogenic receptors (ER), an important ...

  6. CO2 abatement costs of greenhouse gas (GHG) mitigation by different biogas conversion pathways.

    PubMed

    Rehl, T; Müller, J

    2013-01-15

    Biogas will be of increasing importance in the future as a factor in reducing greenhouse gas emissions cost-efficiently by the optimal use of available resources and technologies. The goal of this study was to identify the most ecological and economical use of a given resource (organic waste from residential, commercial and industry sectors) using one specific treatment technology (anaerobic digestion) but applying different energy conversion technologies. Average and marginal abatement costs were calculated based on Life Cycle Cost (LCC) and Life Cycle Assessment (LCA) methodologies. Eight new biogas systems producing electricity, heat, gas or automotive fuel were analyzed in order to identify the most cost-efficient way of reducing GHG emissions. A system using a combined heat and power station (which is connected to waste treatment and digestion operation facilities and located nearby potential residential, commercial or industrial heat users) was found to be the most cost-efficient biogas technology for reducing GHG emissions. Up to € 198 per tonne of CO(2) equivalents can be saved by replacing the "business as usual" systems based on fossil resources with ones based on biogas. Limited gas injection (desulfurized and dried biogas, without compression and upgrading) into the gas grid can also be a viable option with an abatement cost saving of € 72 per tonne of CO(2) equivalents, while a heating plant with a district heating grid or a system based on biogas results in higher abatement costs (€ 267 and € 270 per tonne CO(2) eq). Results from all systems are significantly influenced by whether average or marginal data are used as a reference. Beside that energy efficiency, the reference system that was replaced and the by-products as well as feedstock and investment costs were identified to be parameters with major impacts on abatement costs. The quantitative analysis was completed by a discussion of the role that abatement cost methodology can play in

  7. [A survey on physiological strains of asbestos abatement work wearing protective clothing in summer].

    PubMed

    Tochihara, Y; Ohnaka, T; Nagai, Y; Muramatsu, T

    1993-01-01

    Since the health hazard of asbestos fibers has been widely recognized, the number of asbestos abatement projects in schools has increased rapidly. Most of these projects were planned during summer vacation from school. However, in Japan, it is hot and humid in summer. Moreover, the workers have to wear impermeable protective clothing because of the asbestos exposure risk. The purpose of this survey is to study the workload of asbestos abatement work by measuring physiological reactions. Physiological strains of 12 male workers and working conditions during asbestos abatements work in two schools were measured in August in 1988 and in 1989. Body weight loss by the work of all workers was measured, and heart rate, rectal temperature and skin temperatures at five sites of some of them were measured every minute. In both workplaces, the workers wore disposable coveralls with hoods and shoes covers and protective masks. Air temperature in the workplaces was between 24.6 degrees C and 28.8 degrees C, and air humidity was between 85% and 96%. The high humidity was result of covering the floor, ceiling and wall of the workplaces were covered with vinyl seats, and sprinkling the asbestos fibers with water to lower the amount of asbestos in the air. Working hours of asbestos abatement were between 46 minutes and 95 minutes. Sweat rates were between 217 g/h and 605 g/h. These values were greater compared to the estimate values when work was done wearing commonly used light clothing. Heart rates during asbestos abatement work did not exceed 150 beats/min in one school where the temperature was 25 degrees C-27 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8507292

  8. Investigation of Microbial Respirometry for Monitoring Natural Sulfide Abatement in Geothermal Cooling Tower Basins

    SciTech Connect

    Peter A. Pryfogle

    2005-09-01

    Geothermal plant operators are interested in investigating the ability of micro-organisms found in the cooling tower basin to metabolize and cycle sulfide to less toxic sulfur compounds. If the growth or activity of the organisms participating in sulfur-oxidation could be selectively enhanced, then hydrogen sulfide could be naturally abated in the cooling basin, substantially reducing the costs associated with the chemicals used for abatement. The use of respirometry has been proposed as a technique for monitoring the response of the microbial populations found in geothermal cooling towers to various conditions, including the addition of nutrients such as nitrogen and phosphorus. Respiro-metry is a manometric measurement of dissolved gases that are in equilibrium in a con-fined sample volume. Since microbes expire varying amounts of carbon dioxide or oxygen as they metabolize nutrients, this technique can be used to evaluate their activities in process streams. This report describes a series of experiments designed to determine the suitability of respirometry for tracking microbial activity for evaluating and enhancing natural abatement processes in geothermal cooling basins.

  9. 40 CFR 160.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Physical and chemical characterization... and chemical characterization studies. (a) All provisions of the GLP standards shall apply to physical and chemical characterization studies designed to determine stability, solubility, octanol...

  10. 40 CFR 160.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 25 2012-07-01 2012-07-01 false Physical and chemical characterization... and chemical characterization studies. (a) All provisions of the GLP standards shall apply to physical and chemical characterization studies designed to determine stability, solubility, octanol...

  11. 40 CFR 160.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 25 2013-07-01 2013-07-01 false Physical and chemical characterization... and chemical characterization studies. (a) All provisions of the GLP standards shall apply to physical and chemical characterization studies designed to determine stability, solubility, octanol...

  12. 40 CFR 160.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Physical and chemical characterization... and chemical characterization studies. (a) All provisions of the GLP standards shall apply to physical and chemical characterization studies designed to determine stability, solubility, octanol...

  13. 40 CFR 160.135 - Physical and chemical characterization studies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 24 2011-07-01 2011-07-01 false Physical and chemical characterization... and chemical characterization studies. (a) All provisions of the GLP standards shall apply to physical and chemical characterization studies designed to determine stability, solubility, octanol...

  14. The schoolroom asbestos abatement program: a public policy debacle

    NASA Astrophysics Data System (ADS)

    Ross, M.

    1995-10-01

    It is estimated that nearly 100 billion has been spent on removal of asbestos-bearing materials from schoolrooms, public and commercial buildings, and homes. This removal continues to this day despite the publication of an advisory document in 1990 by the US Environmental Protection Agency that states most removal is unnecessary and is even counterproductive both in terms health protection and costs. Concern over low exposure to substances that are designated as carcinogens is based on the false concept that even the smallest exposure to such substances can increase cancer risk. The expression “one molecule of a chemical or one asbestos fiber can possibly produce a tumor” is repeated over and over until it is accepted as a truth. Over 1400 air samples taken in 219 North American school buildings show the average fiber level to be 0.00022 fibers per milliliter of air. Using the most pessimistic models and attendance in the school for 6 h a day, five days a week, for 14 years, the calculated risk is one excess cancer death per million lifetimes. In contrast, the risk of dying from a lightning strike is 35 deaths per million lifetimes. Ambient air asbestos concentrations measured in the chrysotile asbestos mining towns of Quebec are 220 to 2200 times greater than that measured in the average schoolroom, yet the women living their entire lives in these towns show no increased cancer risk. The asbestos abatement program in the United States is a public policy debacle.

  15. 47 CFR 22.971 - Obligation to abate unacceptable interference.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.971 Obligation to abate unacceptable... licensee that can show that its signal does not directly or indirectly, cause or contribute to...

  16. A METHOD FOR COMPARING MULTICOMPONENT, MULTIMEDIA POLLUTION ABATEMENT PROCESSES

    EPA Science Inventory

    The paper describes a comparison of the cost-effectiveness of four multicomponent, multimedia pollution abatement options: coal cleaning, limestone, limestone plus adipic acid, and coal cleaning plus limestone plus adipic acid. The comparison makes cost-effectiveness evaluations ...

  17. Theoretical study of chemical reactions in solution

    SciTech Connect

    Yokogawa, D.

    2015-12-31

    Quantum chemical calculations in solution are becoming more and more important in chemistry. Reference interaction site model self-consistent field (RISM-SCF) is one of the powerful approaches to perform quantum chemical calculations in solution. In this work, we developed a new generation of RISM-SCF, where a robust fitting method was newly introduced. We applied the new method to tautomerization reaction of cytosine in aqueous phase. Our calculation reproduced experimentally obtained relative stabilities and relative free energies correctly.

  18. Chemical Sputtering Studies of Lithiated Graphite

    NASA Astrophysics Data System (ADS)

    Raman, Priya; Groll, Andrew; Abrams, Tyler; Curreli, Davide; Andruczyk, Daniel; Ruzic, D. N.

    2012-10-01

    Lithium treatments in the National Spherical Torus Experiment have shown dramatic improvements in plasma performance. In order to understand the complex system of lithiated ATJ graphite, chemical sputtering measurements of plain and lithiated ATJ graphite are conducted in IIAX (Ion Surface Interaction Experiment) facility with a differentially pumped Magnetic Sector Residual Gas Analyzer (MSRGA). The ATJ graphite target is mounted in such way that the target can be translated along a line to different positions to get direct comparison of ATJ and lithiated ATJ. Target is heated using joule heating and is connected to a biasing circuitry. Chemical sputtering of graphite is dependent on the ion energy and substrate temperature, hence the total effects of treating ATJ graphite with lithium in hydrogen plasma is investigated in terms of different target temperatures and bias voltages. For this purpose, lithium is evaporated in-situ onto ATJ graphite and chemically sputtered species in hydrogen plasma is measured using MSRGA. The dominant chemical sputtering product is CH4. It was found that lithium treatments have suppressed the chemical sputtering of ATJ Graphite. The suppression of chemical sputtering effect is presented as a function of varying lithium thickness on ATJ Graphite.

  19. A Comparison of Lead Abatement Technologies at Lewis Research Center

    NASA Technical Reports Server (NTRS)

    Jeziorowski, Luz Y.; Calla, Joanne

    1997-01-01

    In 1995, Lewis participated in a pilot test of Lead Specifications. The Specifications were sponsored by the Center to Protect Worker's Rights (CPWR). Entitled "Model Specifications for the Protection of Worker's from Lead on Steel Structures", one aspect of this endeavor was to test and compare several lead abatement technologies. The project overview, objectives, team, and requirements as well as abatement methods and materials are outlined.

  20. Chemical feedbacks in climate sensitivity studies

    NASA Astrophysics Data System (ADS)

    Dietmüller, Simone; Ponater, Michael; Sausen, Robert

    2013-04-01

    Interactively coupled climate chemistry models extend the number of feedback mechanisms in climate change simulations by allowing a variation of several radiatively actice chemical tracers that are prescribed in conventional climate models. Different perturbation experiments including chemical feedbacks were performed using the chemistry-climate model system EMAC coupled to the mixed layer ocean model MLO. The influence of the chemical feedbacks O3, CH4 and N2O on climate response and climate sensitivity is quantified for a series of CO2-perturbation simulations: Equilibrium climate sensitivity is dampened, if chemical feedbacks are included. In case of a CO2 doubling simulation chemical feedbacks decrease climate sensitivity by -3.6% and in case of a 4*CO2 simulation by -8.1%. Analysis of the chemical feedbacks reveals, that the negative feedback of ozone, mainly the feedback of stratospheric ozone, is responsible for this dampening. The radiative feedbacks of CH4 and N2O are negligible, mainly because the model system does not allow interactive emission feedbacks at the Earth's surface for these gases. The feedback of physical parameters is significantly modified by the presence of chemical feedbacks. In case of the CO2-perturbation experiments the negative stratospheric ozone feedback is accompanied by a negative stratospheric H2O feedback change of the same order of magnitude. So the dampening effect of the direct O3 radiative feedback is enhanced. A non-linearity in the damping is found with increasing CO2 concentrations. Reasons are the nonlinear feedbacks of ozone, temperature, and stratospheric water vapor. Additional 6*CO2 simulations with and without chemical feedbacks included show, that the presence of chemic feedbacks helps to prevent a runaway greenhouse effect, as the O3 distribution can react to the upward shift of the tropopause. Also experiments driven by anthropogenic NOx- and CO-emissions were performed, where chemically active trace gases act

  1. The Veterans Administration's Asbestos Abatement Program

    SciTech Connect

    Schepers, G.W. )

    1991-12-31

    The Veterans Administration has developed a program of asbestos abatement for its more than 1000 buildings, where health care personnel from 173 hospitals and 238 ambulatory care clinics are likely to encounter respirable asbestos. This is a costly program, which has averaged about $25 million annually for the past ten years. The VA has banned the use of new asbestos products containing more than 1% of asbestos in building construction or renovation projects. Industrial hygiene engineering programs have been ordered instituted at all VA medical centers to monitor dust levels in compliance with OSHA and EPA requirements. Health surveillance programs, managed by an environmental health physician at each medical center, have been instituted for all personnel who have been identified to have breathed asbestos fibers in excess of OSHA-EPA threshold limit values. The health care program focuses on the identification of asbestosis and asbestos-related cancer through periodic X-ray films, lung function tests, and electrocardiographic and physical examination screening. The program also stresses cessation of smoking.

  2. Nitrogen oxide abatement by distributed fuel addition

    SciTech Connect

    Wendt, J.O.L.; Meraab, J.

    1988-06-27

    This research is directed towards the development of engineering guidelines that define the application of distributed fuel addition as a technique for NOx abatement. It is expected that multiple fuel and air addition in the post-flame of a combustion process will increase free radical concentrations which destroy nitrogenous species and thus help them decay toward their equilibrium concentrations, which can be very low in that region of the combustor. Screening experiments were conducted on a laboratory scale downfired combustor. The objective was to compare NOx emissions arising from various combustion configurations, including fuel and/or air staging. Although the primary focus of this research is on NO control, a secondary effort was directed towards the measurement of N2O emissions from various coal combustion processes. N2O has been identified as a trace gas responsible for stratospheric ozone depletion, and has been hypothesized to arise from combustion processes, in amounts roughly proportional to NO emissions. Results presented in this report showed that the ratio N2O/NO was far from constant. The introduction of secondary air into a combustion process was accompanied an increase in N2O emissions. The measured N2O was always less than 10 ppm even under the most favorable combustion conditions. Reburning with premixed fuel and air mixtures was not effective in reducing NO emissions.

  3. The GABA transaminase, ABAT, is essential for mitochondrial nucleoside metabolism

    PubMed Central

    Besse, Arnaud; Wu, Ping; Bruni, Francesco; Donti, Taraka; Graham, Brett H.; Craigen, William J.; McFarland, Robert; Moretti, Paolo; Lalani, Seema; Scott, Kenneth L.; Taylor, Robert W.; Bonnen, Penelope E.

    2015-01-01

    Summary ABAT is a key enzyme responsible for catabolism of principal inhibitory neurotransmitter gamma-aminobutyric acid (GABA). We report an essential role for ABAT in a seemingly unrelated pathway, mitochondrial nucleoside salvage, and demonstrate that mutations in this enzyme cause an autosomal recessive neurometabolic disorder and mtDNA depletion syndrome (MDS). We describe a family with encephalomyopathic MDS caused by a homozygous missense mutation in ABAT that results in elevated GABA in subjects’ brains as well as decreased mtDNA levels in subjects’ fibroblasts. Nucleoside rescue and co-IP experiments pinpoint that ABAT functions in the mitochondrial nucleoside salvage pathway to facilitate conversion of dNDPs to dNTPs. Pharmacological inhibition of ABAT through the irreversible inhibitor Vigabatrin caused depletion of mtDNA in photoreceptor cells that was prevented through addition of dNTPs in cell culture media. This work reveals ABAT as a connection between GABA metabolism and nucleoside metabolism and defines a neurometabolic disorder that includes MDS. PMID:25738457

  4. Microorganisms and Chemical Pollution

    ERIC Educational Resources Information Center

    Alexander, M.

    1973-01-01

    Discusses the importance of microorganisms in chemical pollution and pollution abatement. Selected chemical pollutants are chosen to illustrate that microorganisms synthesize hazardous substances from reasonably innocuous precursors, while others act as excellent environmental decontaminating agents by removing undesirable natural and synthetic…

  5. 8(E) TRIAGE CHEMICAL STUDIES DATABASE (TSCA)

    EPA Science Inventory

    The Toxic Substances Control Act (TSCA) gives the Environmental Protection Agency (EPA) the authority and responsibility to identify and control chemical hazards to human health or the environment. TSCA gives the EPA authority to gather certain kinds of basic information on chemi...

  6. Physical-chemical studies of transuranium elements

    SciTech Connect

    Peterson, J.R.

    1991-01-01

    Major advances in our continuing program to determine, interpret, and correlate the basic chemical and physical properties of the transuranium elements are summarized. Research topics include: Molar enthalpies of formation of BaCmO{sub 3} and BaCfO{sub 3}; luminescence of europium oxychloride at various pressures; and anti-stokes luminescence of selected actinide (III) compounds. 42 refs., 4 figs., 2 tabs.

  7. PROTEIN ADDUCT FORMING CHEMICALS FOR EXPOSURE MONITORING: CHEMICALS SELECTED FOR FURTHER STUDY

    EPA Science Inventory

    The present report is an in-depth characterization of twenty-two chemicals and the protein (primarily hemoglobin) adducts that are formed following exposure to these compounds. These chemicals were recommended for further study in a recent internal report which described the stat...

  8. [Studies on chemical constituents of Tinospora hainanesis].

    PubMed

    Guo, Y; Lin, L; Shen, J

    1998-05-01

    Tinospora hainanesis is a new species of Menispermaceae plant. It is used as folk remedy for joint pain and physical injury. Five compounds were isolated from the vine stalk of Tinospora hainanesis. By spectral analysis and chemical methods, the structures of the compounds were identified as makisterone A (I), 2,3-dimethoxy-9,10-dihydroxy-N-methyltetrahydroproto-berberine quaternary salt (II), palmatine (III), beta-amyrin (IV) and docosyl ferulate (V). II is a new quaternary alkaloid named as haitinosporine. I, IV and V were isolated for the first time from the plants of Tinospora genus. PMID:12017002

  9. Screening for Chemical Contributions to Breast Cancer Risk: A Case Study for Chemical Safety Evaluation

    PubMed Central

    Ackerman, Janet M.; Dairkee, Shanaz H.; Fenton, Suzanne E.; Johnson, Dale; Navarro, Kathleen M.; Osborne, Gwendolyn; Rudel, Ruthann A.; Solomon, Gina M.; Zeise, Lauren; Janssen, Sarah

    2015-01-01

    Background Current approaches to chemical screening, prioritization, and assessment are being reenvisioned, driven by innovations in chemical safety testing, new chemical regulations, and demand for information on human and environmental impacts of chemicals. To conceptualize these changes through the lens of a prevalent disease, the Breast Cancer and Chemicals Policy project convened an interdisciplinary expert panel to investigate methods for identifying chemicals that may increase breast cancer risk. Methods Based on a review of current evidence, the panel identified key biological processes whose perturbation may alter breast cancer risk. We identified corresponding assays to develop the Hazard Identification Approach for Breast Carcinogens (HIA-BC), a method for detecting chemicals that may raise breast cancer risk. Finally, we conducted a literature-based pilot test of the HIA-BC. Results The HIA-BC identifies assays capable of detecting alterations to biological processes relevant to breast cancer, including cellular and molecular events, tissue changes, and factors that alter susceptibility. In the pilot test of the HIA-BC, chemicals associated with breast cancer all demonstrated genotoxic or endocrine activity, but not necessarily both. Significant data gaps persist. Conclusions This approach could inform the development of toxicity testing that targets mechanisms relevant to breast cancer, providing a basis for identifying safer chemicals. The study identified important end points not currently evaluated by federal testing programs, including altered mammary gland development, Her2 activation, progesterone receptor activity, prolactin effects, and aspects of estrogen receptor β activity. This approach could be extended to identify the biological processes and screening methods relevant for other common diseases. Citation Schwarzman MR, Ackerman JM, Dairkee SH, Fenton SE, Johnson D, Navarro KM, Osborne G, Rudel RA, Solomon GM, Zeise L, Janssen S. 2015

  10. Chemical weapons proliferation in the Middle East. Study project

    SciTech Connect

    Schumeyer, G.

    1990-04-01

    Since the early 1980s, chemical weapons proliferation in the Middle East has been a growing problem. Most recently, the eight year Iran-Iraq War, marked by the repeated use of chemical weapons, has set an alarming precedent in this region that can no longer be ignored. The threat is acute and the implications for the Middle East, an area where animosities are high and relations tense, are significant. The study will address chemical weapons proliferation in the Middle East. It will examine why proliferation occurred and look at initiatives and efforts to prevent proliferation. This study will also discuss the chemical weapons capabilities of the Middle East states, the threat to the region posed by chemical weapons, and some of the implications for balance and stability in the region. Finally, this study will examine future prospects for the region in terms of chemical weapons proliferation there.

  11. Measuring chemical sensitivity prevalence: a questionnaire for population studies.

    PubMed Central

    Kipen, H M; Hallman, W; Kelly-McNeil, K; Fiedler, N

    1995-01-01

    Because no information exists on the prevalence of chemical sensitivity syndromes such as multiple chemical sensitivities, a questionnaire for use in population studies was developed and tested to assess the presence or absence of chemical sensitivity. Seven hundred five individuals attending clinics answered a questionnaire asking whether each of 122 common substances caused symptoms. Results showed that patients with multiple chemical sensitivities and asthma had average total scores that were significantly different from each other and from those of each of the other diagnostic categories. Higher total scores were also reported by female patients. The instrument described here may facilitate meaningful prevalence studies of multiple chemical sensitivities. It will also allow study of chemically induced symptoms in other conditions such as asthma. PMID:7702128

  12. Global forestry emission projections and abatement costs

    NASA Astrophysics Data System (ADS)

    Böttcher, H.; Gusti, M.; Mosnier, A.; Havlik, P.; Obersteiner, M.

    2012-04-01

    In this paper we present forestry emission projections and associated Marginal Abatement Cost Curves (MACCs) for individual countries, based on economic, social and policy drivers. The activities cover deforestation, afforestation, and forestry management. The global model tools G4M and GLOBIOM, developed at IIASA, are applied. GLOBIOM uses global scenarios of population, diet, GDP and energy demand to inform G4M about future land and commodity prices and demand for bioenergy and timber. G4M projects emissions from afforestation, deforestation and management of existing forests. Mitigation measures are simulated by introducing a carbon tax. Mitigation activities like reducing deforestation or enhancing afforestation are not independent of each other. In contrast to existing forestry mitigation cost curves the presented MACCs are not developed for individual activities but total forest land management which makes the estimated potentials more realistic. In the assumed baseline gross deforestation drops globally from about 12 Mha in 2005 to below 10 Mha after 2015 and reach 0.5 Mha in 2050. Afforestation rates remain fairly constant at about 7 Mha annually. Although we observe a net area increase of global forest area after 2015 net emissions from deforestation and afforestation are positive until 2045 as the newly afforested areas accumulate carbon rather slowly. About 200 Mt CO2 per year in 2030 in Annex1 countries could be mitigated at a carbon price of 50 USD. The potential for forest management improvement is very similar. Above 200 USD the potential is clearly constrained for both options. In Non-Annex1 countries avoided deforestation can achieve about 1200 Mt CO2 per year at a price of 50 USD. The potential is less constrained compared to the potential in Annex1 countries, achieving a potential of 1800 Mt CO2 annually in 2030 at a price of 1000 USD. The potential from additional afforestation is rather limited due to high baseline afforestation rates assumed

  13. Yale FICSIT: risk factor abatement strategy for fall prevention.

    PubMed

    Tinetti, M E; Baker, D I; Garrett, P A; Gottschalk, M; Koch, M L; Horwitz, R I

    1993-03-01

    Based on finding a strong association between number of impairments and risk of falling in earlier studies, Yale FICSIT investigators are conducting an intervention trial comparing the effectiveness of usual care plus social visits (SV) and a targeted risk abatement intervention (TI) strategy in reducing falls among at risk community elderly persons. Subjects include members of a participating HMO who are > or = 70 years of age, cognitively intact, not terminally ill, not too physically active, and possess at least one fall risk factor. The targeted risk factors include postural hypotension; sedative use; at least four targeted medications; upper and lower extremity strength and range of motion impairments; foot problems; and balance, gait, and transfer dysfunctions. The interventions include medication adjustments, behavioral change recommendations, education and training, and home-based exercise regimens targeting the identified risk factors. The interventions are carried out by the study nurse practitioner and physical therapist in TI subjects' homes. The SV subjects receive a comparable number of home visits as the TI subjects during which a structured life review is performed by social work students. The primary outcome is occurrence of falls during the 12-month followup. Secondary outcomes include change in mobility performance and fall-related efficacy. PMID:8440856

  14. Chemical Equilibrium in Supramolecular Systems as Studied by NMR Spectrometry

    ERIC Educational Resources Information Center

    Gonzalez-Gaitano, Gustavo; Tardajos, Gloria

    2004-01-01

    Undergraduate students are required to study the chemical balance in supramolecular assemblies constituting two or more interacting species, by using proton NMR spectrometry. A good knowledge of physical chemistry, fundamentals of chemical balance, and NMR are pre-requisites for conducting this study.

  15. Chemical ecology: studies from East Africa.

    PubMed

    Meinwald, J; Prestwich, G D; Nakanishi, K; Kubo, I

    1978-03-17

    The International Centre of Insect Physiology and Ecology (ICIPE), in Nairobi, provides a laboratory at which a multinational group of scientists pursues interdisciplinary research. In collaboration with their colleagues in biology, ICIPE chemists have characterized the sex pheromones of the tick which serves as a vector of East Coast fever and have identified a termite queen-cell-building pheromone. The structure of many anthropod defensive chemicals have been determined; most interesting of these are the trinervitenes, structurally novel diterpenoids from nasute termites. Several highly active insect antifeedants were discovered using a simple bioassay to screen selected East African plants. These antifeedants may provide leads for the development of new insect-control techniques. PMID:17745589

  16. [Studies on chemical compounds of Chlorella sorokiniana].

    PubMed

    Zhang, Ling; Liu, Ping-huai; Wu, Jiao-na; Yang, Guo-fu; Suo, Yang-yang; Luo, Ning; Chen, Chen

    2015-04-01

    Chemical constituents of Chlorella sorokiniana were isolated and purified by repeated column chromatographies, over silicagel and Sephadex LH-20. Their structures were identified on the basis of physicochemical properties and spectroscopic data analysis. Five compounds were obtained from the petroleum ether extract of Chlorella sorokiniana, and their structures were identified as (22E, 24R)-5alpha, 3beta-epidioxiergosta-6, 22-dien-3beta-ol(1),(24S)-ergosta-7-en-3beta-ol(2), loliolide(3), stigmasta-7,22-dien-3beta,5alpha,6alpha-triol(4), and 3beta-hydroxy-5alpha,6alpha-epoxy-7-megastigmen-9-one(5). The main liposoluble fractions from Chlorella sorokiniana maiuly contain fatty acids, alkyl acids and olefine acids. Components 1-5 were isolated from the genus Chlorella for the first time. PMID:26281556

  17. Risk management for sulfur dioxide abatement under multiple uncertainties

    NASA Astrophysics Data System (ADS)

    Dai, C.; Sun, W.; Tan, Q.; Liu, Y.; Lu, W. T.; Guo, H. C.

    2016-03-01

    In this study, interval-parameter programming, two-stage stochastic programming (TSP), and conditional value-at-risk (CVaR) were incorporated into a general optimization framework, leading to an interval-parameter CVaR-based two-stage programming (ICTP) method. The ICTP method had several advantages: (i) its objective function simultaneously took expected cost and risk cost into consideration, and also used discrete random variables and discrete intervals to reflect uncertain properties; (ii) it quantitatively evaluated the right tail of distributions of random variables which could better calculate the risk of violated environmental standards; (iii) it was useful for helping decision makers to analyze the trade-offs between cost and risk; and (iv) it was effective to penalize the second-stage costs, as well as to capture the notion of risk in stochastic programming. The developed model was applied to sulfur dioxide abatement in an air quality management system. The results indicated that the ICTP method could be used for generating a series of air quality management schemes under different risk-aversion levels, for identifying desired air quality management strategies for decision makers, and for considering a proper balance between system economy and environmental quality.

  18. Environmental projects. Volume 1: Polychlorinated biphenyl (PCB) abatement program

    NASA Technical Reports Server (NTRS)

    Kushner, L.

    1987-01-01

    Six large parabolic dish antennas are located at the Goldstone Deep Space Communications Complex north of Barstow, California. Some of the ancillary electrical equipment of thes Deep Space Stations, particularly transformers and power capicitors, were filled with stable, fire-retardant, dielectric fluids containing substances called polychlorobiphenyls (PCBs). Because the Environmental Protection Agency has determined that PCBs are environmental pollutants toxic to humans, all NASA centers have been asked to participate in a PCB-abatement program. Under the supervision of JPL's Office of Telecommunications and Data Acquisition, a two-year long PCB-abatement program has eliminated PCBs from the Goldstone Complex.

  19. Investigating fossil hydrothermal systems by means of fluid inclusions and stable isotopes in banded travertine: an example from Castelnuovo dell'Abate (southern Tuscany, Italy)

    NASA Astrophysics Data System (ADS)

    Rimondi, Valentina; Costagliola, Pilario; Ruggieri, Giovanni; Benvenuti, Marco; Boschi, Chiara; Brogi, Andrea; Capezzuoli, Enrico; Morelli, Guia; Gasparon, Massimo; Liotta, Domenico

    2016-03-01

    Southern Tuscany (Italy) hosts geothermal anomalies with associated widespread CO2 gas-rich manifestations and active travertine-deposing thermal springs. Geothermal anomalies have been active since the Late Miocene and have led to the formation of widespread Late Miocene-Pleistocene travertine deposits and meso- and epithermal mineralizations. This study investigates the travertine deposit exposed in the Castelnuovo dell'Abate area of southern Tuscany. Here, a fissure-ridge type travertine deposit and its feeding conduits, currently filled with banded calcite veins (i.e. banded travertine), represent a spectacular example of fossil hydrothermal circulation in the peripheral area of the exploited Monte Amiata geothermal field. The Castelnuovo dell'Abate travertine deposit and associated calcite veins were analysed to establish the characteristics of the parent hydrothermal fluids, and the age of this circulation. The focus of the study was on fluid inclusions, rarely considered in travertine studies, but able to provide direct information on the physico-chemical characteristics of the original fluid. Uranium-thorium geochronological data provided further constraints on the: (1) age of tectonic activity; (2) age of the hydrothermal circulation; and (3) evolution of the Monte Amiata geothermal anomaly. Results indicate that brittle deformation (NW- and SE-trending normal to oblique-slip faults) was active during at least the Middle Pleistocene and controlled a hydrothermal circulation mainly characterized by fluids of meteoric origin, and as old as 300-350 ka. This is the oldest circulation documented to date in the Monte Amiata area. The fluid chemical composition is comparable to that of fluids currently exploited in the shallow reservoir of the Monte Amiata geothermal field, therefore suggesting that fluid composition has not changed substantially over time. These fluids, however, have cooled by about 70 °C in the last 300-350 ka, corresponding to a cooling rate

  20. A Regionally-Specific Assessment of the Carbon Abatement Potential of Biochar

    NASA Astrophysics Data System (ADS)

    Birch, G.; Field, J.; Keske, C.; DeFoort, M.; Cotrufo, M.

    2012-12-01

    Biochar, the solid carbon-rich co-product of certain bioenergy conversion technologies, is receiving a great deal of attention as a strategy for sequestering carbon in soils and improving the performance of agricultural systems. Several studies have attempted to quantify the lifecycle carbon abatement potential of biochar systems, considering emissions associated with feedstock provisioning and processing, energy co-production, agronomic system impacts (yield increases and nitrous oxide emission suppression), and the recalcitrance of biochar in soil, as well as accounting for the carbon abatement value of using the char as a fuel that is foregone when it is used as a soil amendment instead. These assessments typically focus on biochar production in advanced, efficient slow pyrolysis systems, despite the fact that much biochar is currently produced through small-scale carbonization or gasification systems that lack energy recovery or even emission control capability. Here, a mechanistic biochar system assessment model is presented, capable of estimating system carbon abatement value and profitability for different feedstocks, conversion technologies and temperatures, and application into different agricultural soils. The variation of biochar recalcitrance in soil as a function of production temperature is considered, and agricultural impacts are assessed in the context of biochar's liming value, an effect that is straightforward to quantify and that has often been implicated in observed crop yield increases or nitrous oxide emission reductions. The analysis is rigorous in that tradeoffs between biochar production quantity and quality are endogenized, but conservative in that other potential agronomic benefits of biochar (e.g. improved soil water holding capacity) are not considered. This model is applied to a case study of bioenergy and biochar co-production in northern Colorado using beetle-killed pine wood and slash as a feedstock. Preliminary results suggest that

  1. Recent achievements in chemical studies of heaviest elements

    NASA Astrophysics Data System (ADS)

    Gäggeler, H. W.

    2011-09-01

    Discovery of heavy elements up to atomic number 118 at FLNR in Dubna has paved the way to also extend chemical knowledge to heavier members of the periodic table. Recent studies on the chemical properties of Cn and element 114 are summarized that have been performed at FLNR in Dubna using the fusion reactions 48Ca + 242/244Pu.

  2. NATIONAL STUDY OF CHEMICAL RESIDUES IN FISH - III. STUDY RESULTS

    EPA Science Inventory

    Bottom feeding and game fish, from each of nearly 400 sites throughout the United States were analyzed for 15 PCDD/PCDFS, PCBS, 21 pesticides and herbicides, and 13 other organic chemicals. and mercury. even of the PCDD/PCDFs and 15 of the other chemicals were detected at over 50...

  3. Low-thrust chemical rocket engine study

    NASA Technical Reports Server (NTRS)

    Mellish, J. A.

    1981-01-01

    Engine data and information are presented to perform system studies on cargo orbit-transfer vehicles which would deliver large space structures to geosynchronous equatorial orbit. Low-thrust engine performance, weight, and envelope parametric data were established, preliminary design information was generated, and technologies for liquid rocket engines were identified. Two major engine design drivers were considered in the study: cooling and engine cycle options. Both film-cooled and regeneratively cooled engines were evaluated. The propellant combinations studied were hydrogen/oxygen, methane/oxygen, and kerosene/oxygen.

  4. Low-thrust chemical rocket engine study

    NASA Technical Reports Server (NTRS)

    Mellish, J. A.

    1980-01-01

    Parametric data and preliminary designs on liquid rocket engines for low thrust cargo orbit-transfer-vehicles are described and those items where technology is required to enhance the designs are identified. The results of film cooling studies to establish the upper chamber pressure limit are given. The study showed that regen cooling with RP-1 was not feasible over the entire thrust and chamber pressure ranges. The thermal data showed that the RP-1 bulk temperature exceeded the study coking temperature limit of 1010 R. Based upon the results presented, O2/H2 and O2/CH4 regen engine systems and O2/H2 film cooled engines were selected for further study in the system analysis. Six engine design concepts are examined.

  5. Marginal abatement cost curve for NOx incorporating controls, renewable electricity, energy efficiency and fuel switching

    EPA Science Inventory

    A marginal abatement cost curve (MACC) traces out the relationship between the quantity of pollution abated and the marginal cost of abating each additional unit. In the context of air quality management, MACCs typically are developed by sorting end-of-pipe controls by their resp...

  6. Marginal abatement cost curves for NOx incorporating both controls and alternative measures

    EPA Science Inventory

    A marginal abatement cost curve (MACC) traces out the efficient marginal abatement cost level for any aggregate emissions target when a least cost approach is implemented. In order for it to represent the efficient MAC level, all abatement opportunities across all sectors and loc...

  7. 23 CFR 772.9 - Analysis of traffic noise impacts and abatement measures.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 23 Highways 1 2011-04-01 2011-04-01 false Analysis of traffic noise impacts and abatement measures... AND ENVIRONMENT PROCEDURES FOR ABATEMENT OF HIGHWAY TRAFFIC NOISE AND CONSTRUCTION NOISE § 772.9 Analysis of traffic noise impacts and abatement measures. (a) The highway agency shall determine...

  8. 23 CFR 772.9 - Analysis of traffic noise impacts and abatement measures.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Analysis of traffic noise impacts and abatement measures... Analysis of traffic noise impacts and abatement measures. (a) The highway agency shall determine and..., giving weight to the benefits and cost of abatement, and to the overall social, economic...

  9. 47 CFR 22.971 - Obligation to abate unacceptable interference.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SERVICES PUBLIC MOBILE SERVICES Cellular Radiotelephone Service § 22.971 Obligation to abate unacceptable..., causes or contributes to causing unacceptable interference to a non-cellular part 90 of this chapter... or indirectly, cause or contribute to causing unacceptable interference to a non-cellular part 90...

  10. SO2 ABATEMENT FOR COAL-FIRED BOILERS IN JAPAN

    EPA Science Inventory

    The report is a compilation of information on the current status of SO2 abatement technologies for coal-fired boilers in Japan, where strict ambient air quality standards for SO2 and NOx mandate the use of various air pollution control technologies. It focuses on flue gas desulfu...

  11. EVALUATION OF POLLUTION ABATEMENT ALTERNATIVES: PICILLO PROPERTY, COVENTRY, RHODE ISLAND

    EPA Science Inventory

    This report describes the second phase of a two-phase investigation undertaken by the MITRE Corp. to determine the nature and severity of ground and surface water contamination at the Picillo property in Coventry, Rhode Island and to make recommendations for permanent abatement o...

  12. 26 CFR 301.6656-1 - Abatement of penalty.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ....6656-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) PROCEDURE AND ADMINISTRATION PROCEDURE AND ADMINISTRATION Additions to the Tax, Additional Amounts, and Assessable Penalties Additions to the Tax and Additional Amounts § 301.6656-1 Abatement of penalty. (a) Exception for first...

  13. Noise levels near streets, effectiveness and cost abatement measures

    NASA Technical Reports Server (NTRS)

    Lang, J.

    1980-01-01

    During the years 1975-1978, research was carried concerning the current noise levels near streets, the annoyance felt by the population, possible noise abatement measures for these streets, and the economic impact of such measures. The results of the research are summarized.

  14. Contracting for Asbestos Abatement: What You Need to Know.

    ERIC Educational Resources Information Center

    Bittle, Edgar H.; McAllister, Jane B.

    1990-01-01

    School districts are required to determine if asbestos-containing materials exist at school facilities and design and implement asbestos abatement. Reviews how to select a contractor, draft the contract, and ensure its proper implementation by complying with the law and avoiding liability. (MLF)

  15. PFC Abatement in Capacitevely-Coupled Plasma Reactor

    NASA Astrophysics Data System (ADS)

    Porshnev, P. I.; Alaoui, M.; Diamant, Stela; Francis, Terry; Raoux, Sebastien; Woolston, Mike

    2001-10-01

    A low-pressure plasma reactor, was developed to reduce PFC emissions of dielectric etch tools, is a point-of-use environmentally and economically sound solution. Generally, local electric fields in capacitively-coupled (CC) plasmas are higher than in inductively-coupled (IC) plasmas. As a result, electron energy distributions in CC plasmas have more pronounced high-energy part compared to the ones in IC plasmas. This is particularly important for effective breaking of the strong C-F bonds, which dissociation potentials are observably higher than the average electron energy. CC plasma in the Pegasys (Plasma Exhaust Gas Abatement SYStem) reactor was found to be in so-called g-regime, in which ionization is provided with secondary emission electrons. Though in these plasmas, the majority of electrons still reside in plasma bulk, the most important discharge characteristics, in particular, the abatement efficiency, are determined by highly-energetic electrons from sheath zones. With water being added to the incoming gas mixture, better than 95% destruction removal efficiency of the PFCs has been achieved for all dielectric etch applications. CC plasma-based abatement significantly differs from existing abatement methods, especially combustion and catalytic oxidation, which are much less environmentally friendly and economically viable.

  16. Studies on Semantic Systems Chemical Biology

    ERIC Educational Resources Information Center

    Chen, Bin

    2012-01-01

    Current "one disease, one target and one drug" drug development paradigm is under question as relatively few drugs have reached the market in the last two decades. Increasingly research focus is being placed on the study of drug action against biological systems as a whole rather than against a single component (called "Systems…

  17. POLLUTION ABATEMENT IN A COPPER WIRE MILL

    EPA Science Inventory

    This Capsule Report shows how water consumption in copper wire mills can be reduced by 90%. The reduction was from 200,000 gallons per day to 20,000 gallons per day by chemical rinsing and water reuse. The sulfuric acid pickle was regenerated and high purity metallic copper recov...

  18. Spectroscopic and quantum chemical studies on bromopyrazone

    NASA Astrophysics Data System (ADS)

    Gökce, Halil; Bahçeli, Semiha

    2014-12-01

    In this study, the FT-IR, micro-Raman and UV-vis. spectra of bromopyrazone molecule, C10H8BrN3O, (with synonym,1-phenyl-4-amino-5-bromopyridazon-(6) or 5-amino-4-bromo-2-phenyl-3(2H)-pyridazinone) were recorded experimentally. The molecular structure, vibrational wavenumbers, electronic transition absorption wavelengths in ethanol solvent, HOMOs and LUMOs analyses, molecular electrostatic potential (MEP), natural bond orbitals (NBO), nonlinear optical (NLO) properties and atomic charges of bromopyrazone molecule have been calculated by using DFT/B3LYP method with 6-311++G(d,p) basis set in ground state. The obtained results show that the calculated vibrational frequencies and UV-vis. values are in a good agreement with experimental data.

  19. Dunite 72417 - A chemical study and interpretation

    NASA Technical Reports Server (NTRS)

    Laul, J. C.; Schmitt, R. A.

    1975-01-01

    The rock selected for the study is one of the rare ultrabasic rocks, which seems to have survived early lunar differentiation. The Rb-Sr internal isochron for this dunite gave an age of about 4.55 AE. The dunite was sampled at Apollo 17, Station 2 from a single 10x20-cm clast incorporated into a KREEP-rich blue-gray breccia 72435, Boulder 3. Nine dunite samples were analyzed with the aid of instrumental and radiochemical neutron activation analysis procedures. Data for 27 elements are shown in a table. Attention is given to trapped liquid (magma), a garnet hypothesis, models for the dunite genesis, and magma compositions from which 15415 and 72417 crystallized.

  20. Chemical-Free Cosmetics May Be Safer for Teen Girls, Study Suggests

    MedlinePlus

    ... Chemical-Free Cosmetics May Be Safer for Teen Girls, Study Suggests Lower levels of hormone-disrupting chemicals ... hormone-disrupting chemicals in the bodies of teen girls, a new study reports. Chemicals widely used in ...

  1. Millifluidics for Chemical Synthesis and Time-resolved Mechanistic Studies

    PubMed Central

    Krishna, Katla Sai; Biswas, Sanchita; Navin, Chelliah V.; Yamane, Dawit G.; Miller, Jeffrey T.; Kumar, Challa S.S.R.

    2013-01-01

    Procedures utilizing millifluidic devices for chemical synthesis and time-resolved mechanistic studies are described by taking three examples. In the first, synthesis of ultra-small copper nanoclusters is described. The second example provides their utility for investigating time resolved kinetics of chemical reactions by analyzing gold nanoparticle formation using in situ X-ray absorption spectroscopy. The final example demonstrates continuous flow catalysis of reactions inside millifluidic channel coated with nanostructured catalyst. PMID:24327099

  2. Millifluidics for chemical synthesis and time-resolved mechanistic studies.

    PubMed

    Krishna, Katla Sai; Biswas, Sanchita; Navin, Chelliah V; Yamane, Dawit G; Miller, Jeffrey T; Kumar, Challa S S R

    2013-01-01

    Procedures utilizing millifluidic devices for chemical synthesis and time-resolved mechanistic studies are described by taking three examples. In the first, synthesis of ultra-small copper nanoclusters is described. The second example provides their utility for investigating time resolved kinetics of chemical reactions by analyzing gold nanoparticle formation using in situ X-ray absorption spectroscopy. The final example demonstrates continuous flow catalysis of reactions inside millifluidic channel coated with nanostructured catalyst. PMID:24327099

  3. Chemical Modeling for Studies of GeoTRACE Capabilities

    NASA Technical Reports Server (NTRS)

    2005-01-01

    Geostationary measurements of tropospheric pollutants with high spatial and temporal resolution will revolutionize the understanding and predictions of the chemically linked global pollutants aerosols and ozone. However, the capabilities of proposed geostationary instruments, particularly GeoTRACE, have not been thoroughly studied with model simulations. Such model simulations are important to answer the questions and allay the concerns that have been expressed in the atmospheric sciences community about the feasibility of such measurements. We proposed a suite of chemical transport model simulations using the EPA Models 3 chemical transport model, which obtains its meteorology from the MM-5 mesoscale model. The model output consists of gridded abundances of chemical pollutants and meteorological parameters every 30-60 minutes for cases that have occurred in the Eastern United States. This output was intended to be used to test the GeoTRACE capability to retrieve the tropospheric columns of these pollutants.

  4. A chemical EOR benchmark study of different reservoir simulators

    NASA Astrophysics Data System (ADS)

    Goudarzi, Ali; Delshad, Mojdeh; Sepehrnoori, Kamy

    2016-09-01

    chemical design for field-scale studies using commercial simulators. The benchmark tests illustrate the potential of commercial simulators for chemical flooding projects and provide a comprehensive table of strengths and limitations of each simulator for a given chemical EOR process. Mechanistic simulations of chemical EOR processes will provide predictive capability and can aid in optimization of the field injection projects. The objective of this paper is not to compare the computational efficiency and solution algorithms; it only focuses on the process modeling comparison.

  5. Environmental projects. Volume 12: Friable asbestos abatement, GDSCC

    NASA Technical Reports Server (NTRS)

    1990-01-01

    The Goldstone Deep Space Communications Complex (GDSCC) is part of the NASA Deep Space Network, one of the world's largest and most sensitive scientific telecommunications and radio navigation networks. Activities at the GDSCC are carried out in support of six large parabolic dish antennas. These activities may give rise to a variety of environmental hazards, particularly the danger of exposure of GDSCC personnel to asbestos fibers that have been shown to be responsible for such serious ailments as asbestosis, lung cancer, and mesothelioma. Asbestos-containing materials (ACM's) were used in the construction of many of the approximately 100 buildings and structures that were built at the GDSCC during a 30-year period from the 1950s through 1980s. The friable asbestos-abatement program at the GDSCC is presented which consists of text, illustrations, and tables that describe the friable asbestos abatement carried out at the GDSCC from December 21, 1988 through May 11, 1989.

  6. Latency attention deficit: Asbestos abatement workers need us to investigate.

    PubMed

    Roelofs, Cora

    2015-12-01

    Little is known of the impact of asbestos on the health of the workers in the United States who have removed or abated asbestos from buildings following recognition of its adverse effects on health. The United States does not have a national occupational health surveillance network to monitor asbestos-related disease and, while the United States Occupational Health and Safety Administration has a strong and detailed asbestos standard, its enforcement resources are limited. A significant proportion of asbestos abatement workers are foreign-born, and may face numerous challenges in achieving safe workplaces, including lack of union representation, economic vulnerability, and inadequate training. Public health surveillance and increased and coordinated enforcement is needed to monitor the health and exposure experiences of asbestos-exposed workers. Alarming disease trends in asbestos removal workers in Great Britain suggest that, in the United States, increased public attention will be necessary to end the epidemic of asbestos-related disease. PMID:26523746

  7. HUD lead-based-paint abatement demonstration (FHA)

    SciTech Connect

    Not Available

    1991-08-01

    The toxic effects of lead on human beings, and particularly on young children, have been known for many years. Amendments to the Lead-Based Paint Poisoning Prevention Act (LPPPA) in 1987 and 1988 required the U.S. Department of Housing and Urban Development (HUD) to undertake a lead-based paint abatement demonstration program. The overall objective of the demonstration was to 'utilize a sufficient number of abatement methods in a sufficient number of areas and circumstances to demonstrate their relative cost-effectiveness...' One component of the demonstration was conducted in HUD-owned, vacant, single-family properties and was completed in the fall of 1990. A public housing component is expected to be completed in 1991. The report describes the objectives, research design, experience and findings of the completed component, which is generally known as the FHA demonstration, named after the Federal Housing Administration, which held title to the houses.

  8. Microwave plasma torch abatement of NF3 and SF6

    NASA Astrophysics Data System (ADS)

    Hong, Yong Cheol; Uhm, Han Sup; Chun, Byung Jun; Lee, Sun Ku; Hwang, Sang Kyu; Kim, Dong Su

    2006-03-01

    An atmospheric pressure microwave plasma torch as a tool for fluorinated compounds (FCs) abatement was presented. Detailed experiments were conducted on the abatement of NF3 and SF6 in terms of destruction and removal efficiency (DRE) using Fourier transform infrared (FTIR). Swirl gas, compressed air for stable plasma, was tangentially injected into the microwave plasma torch and a mixture of N2, NF3, or SF6, and C2H4 was axially injected. The DRE of 99.1% for NF3 was achieved without an additive gas at the total flow rate of 50.1 liters per minute (lpm) by applying a microwave power of 1.4kW. Also, a DRE of SF6 up to 90.1% was obtained at the total flow rate of 40.6lpm using an applied microwave power of 1.4kW. Experimental results indicate that the microwave plasma abatement device can successfully eliminate FCs in the semiconductor industry.

  9. Chemical Studies of the Transactinide Elements at JAEA

    SciTech Connect

    Nagame, Y.; Asai, M.; Hirata, M.; Ishii, Y.; Nishinaka, I.; Tome, H.; Toyoshima, A.; Tsukada, K.; Akiyama, K.; Goto, S.; Haba, H.

    2006-11-02

    Chemical properties of the transactinide element, rutherfordium (Rf), produced in the reaction 248Cm(18O, 5n) have been studied based on an atom-at-a-time scale. Ion-exchange chromatographic experiments on Rf together with the lighter homologues in the periodic table of the elements, group-4 elements Zr and Hf, in hydrofluoric acid solutions have been conducted with a rapid chemical separation apparatus. From the systematic study of the anion-exchange behavior of Rf, we have observed unexpected chemical behavior of Rf; the fluoride complex formation of Rf is significantly different from those of the homologues. Characteristics of the complexing strength of the Rf fluoride are briefly discussed by comparing with those of the homologues and with theoretical predictions by relativistic molecular density-functional calculations.

  10. Electron Spectroscopy for Chemical Analysis (ESCA) study of atmospheric particles

    NASA Technical Reports Server (NTRS)

    Dillard, J. G.; Seals, R. D.; Wightman, J. P.

    1979-01-01

    The results of analyses by ESCA (Electron Spectroscopy for Chemical Analysis) on several Nuclepore filters which were exposed during air pollution studies are presented along with correlative measurements by Neutron Activation Analysis and Scanning Electron Microscopy. Samples were exposed during air pollution studies at Norfolk, Virginia and the NASA Kennedy Space Center (KSC). It was demonstrated that with the ESCA technique it was possible to identify the chemical (bonding) state of elements contained in the atmospheric particulate matter collected on Nuclepore filters. Sulfur, nitrogen, mercury, chlorine, alkali, and alkaline earth metal species were identified in the Norfolk samples. ESCA binding energy data for aluminum indicated that three chemically different types of aluminum are present in the launch and background samples from NASA-KSC.

  11. Estimating the financial risks of Andropogon gayanus to greenhouse gas abatement projects in northern Australia

    NASA Astrophysics Data System (ADS)

    Adams, Vanessa M.; Setterfield, Samantha A.

    2013-06-01

    Financial mechanisms such as offsets are one strategy to abate greenhouse gas emissions, and the carbon market is expanding with a growing demand for offset products. However, in the case of carbon offsets, if the carbon is released due to intentional or unintentional reversal through environmental events such as fire, the financial liability to replace lost offsets will likely fall on the provider. This liability may have implications for future participation in programmes, but common strategies such as buffer pool and insurance products can be used to minimize this liability. In order for these strategies to be effective, an understanding of the spatial and temporal distributions of expected reversals is needed. We use the case study of savanna burning, an approved greenhouse gas abatement methodology under the Carbon Farming Initiative in Australia, to examine potential risks to carbon markets in northern Australia and quantify the financial risks. We focus our analysis on the threat of Andropogon gayanus (gamba grass) to savanna burning due to its documented impacts of increased fuel loads and altered fire regimes. We assess the spatial and financial extent to which gamba grass poses a risk to savanna burning programmes in northern Australia. We find that 75% of the eligible area for savanna burning is spatially coincident with the high suitability range for gamba grass. Our analysis demonstrates that the presence of gamba grass seriously impacts the financial viability of savanna burning projects. For example, in order to recuperate the annual costs of controlling 1 ha of gamba grass infestation, 290 ha of land must be enrolled in annual carbon abatement credits. Our results show an immediate need to contain gamba grass to its current extent to avoid future spread into large expanses of land, which are currently profitable for savanna burning.

  12. Reforestation as a novel abatement and compliance measure for ground-level ozone.

    PubMed

    Kroeger, Timm; Escobedo, Francisco J; Hernandez, José L; Varela, Sebastián; Delphin, Sonia; Fisher, Jonathan R B; Waldron, Janice

    2014-10-01

    High ambient ozone (O3) concentrations are a widespread and persistent problem globally. Although studies have documented the role of forests in removing O3 and one of its precursors, nitrogen dioxide (NO2), the cost effectiveness of using peri-urban reforestation for O3 abatement purposes has not been examined. We develop a methodology that uses available air quality and meteorological data and simplified forest structure growth-mortality and dry deposition models to assess the performance of reforestation for O3 precursor abatement. We apply this methodology to identify the cost-effective design for a hypothetical 405-ha, peri-urban reforestation project in the Houston-Galveston-Brazoria O3 nonattainment area in Texas. The project would remove an estimated 310 tons of (t) O3 and 58 t NO2 total over 30 y. Given its location in a nitrogen oxide (NOx)-limited area, and using the range of Houston area O3 production efficiencies to convert forest O3 removal to its NOx equivalent, this is equivalent to 127-209 t of the regulated NOx. The cost of reforestation per ton of NOx abated compares favorably to that of additional conventional controls if no land costs are incurred, especially if carbon offsets are generated. Purchasing agricultural lands for reforestation removes this cost advantage, but this problem could be overcome through cost-share opportunities that exist due to the public and conservation benefits of reforestation. Our findings suggest that peri-urban reforestation should be considered in O3 control efforts in Houston, other US nonattainment areas, and areas with O3 pollution problems in other countries, wherever O3 formation is predominantly NOx limited. PMID:25201970

  13. Reforestation as a novel abatement and compliance measure for ground-level ozone

    PubMed Central

    Kroeger, Timm; Escobedo, Francisco J.; Hernandez, José L.; Varela, Sebastián; Delphin, Sonia; Fisher, Jonathan R. B.; Waldron, Janice

    2014-01-01

    High ambient ozone (O3) concentrations are a widespread and persistent problem globally. Although studies have documented the role of forests in removing O3 and one of its precursors, nitrogen dioxide (NO2), the cost effectiveness of using peri-urban reforestation for O3 abatement purposes has not been examined. We develop a methodology that uses available air quality and meteorological data and simplified forest structure growth-mortality and dry deposition models to assess the performance of reforestation for O3 precursor abatement. We apply this methodology to identify the cost-effective design for a hypothetical 405-ha, peri-urban reforestation project in the Houston–Galveston–Brazoria O3 nonattainment area in Texas. The project would remove an estimated 310 tons of (t) O3 and 58 t NO2 total over 30 y. Given its location in a nitrogen oxide (NOx)-limited area, and using the range of Houston area O3 production efficiencies to convert forest O3 removal to its NOx equivalent, this is equivalent to 127–209 t of the regulated NOx. The cost of reforestation per ton of NOx abated compares favorably to that of additional conventional controls if no land costs are incurred, especially if carbon offsets are generated. Purchasing agricultural lands for reforestation removes this cost advantage, but this problem could be overcome through cost-share opportunities that exist due to the public and conservation benefits of reforestation. Our findings suggest that peri-urban reforestation should be considered in O3 control efforts in Houston, other US nonattainment areas, and areas with O3 pollution problems in other countries, wherever O3 formation is predominantly NOx limited. PMID:25201970

  14. Modeling Dynamics of Culex pipiens Complex Populations and Assessing Abatement Strategies for West Nile Virus

    PubMed Central

    Pawelek, Kasia A.; Hager, Elizabeth J.; Hunt, Gregg J.

    2014-01-01

    The primary mosquito species associated with underground stormwater systems in the United States are the Culex pipiens complex species. This group represents important vectors of West Nile virus (WNV) throughout regions of the continental U.S. In this study, we designed a mathematical model and compared it with surveillance data for the Cx. pipiens complex collected in Beaufort County, South Carolina. Based on the best fit of the model to the data, we estimated parameters associated with the effectiveness of public health insecticide (adulticide) treatments (primarily pyrethrin products) as well as the birth, maturation, and death rates of immature and adult Cx. pipiens complex mosquitoes. We used these estimates for modeling the spread of WNV to obtain more reliable disease outbreak predictions and performed numerical simulations to test various mosquito abatement strategies. We demonstrated that insecticide treatments produced significant reductions in the Cx. pipiens complex populations. However, abatement efforts were effective for approximately one day and the vector mosquitoes rebounded until the next treatment. These results suggest that frequent insecticide applications are necessary to control these mosquitoes. We derived the basic reproductive number (ℜ0) to predict the conditions under which disease outbreaks are likely to occur and to evaluate mosquito abatement strategies. We concluded that enhancing the mosquito death rate results in lower values of ℜ0, and if ℜ0<1, then an epidemic will not occur. Our modeling results provide insights about control strategies of the vector populations and, consequently, a potential decrease in the risk of a WNV outbreak. PMID:25268229

  15. Chemical studies of L-chondrites. I - A study of possible chemical sub-groups

    NASA Astrophysics Data System (ADS)

    Neal, C. W.; Dodd, R. T.; Jarosewich, E.; Lipschutz, M. E.

    1981-06-01

    Radiochemical neutron activation analysis of Ag, As, Au, Bi, Co, Cs, Ga, In, Rb, Sb, Te, Tl and Zn and major element data in 14 L4-6 and 3 LL5 chondrites indicates that the L-group is unusually variable and may represent at least 2 sub-groups differing in formation history. Chemical trends in the S/Fe-rich sub-group support textural evidence indicating late loss of a shock-formed Fe-Ni-S melt; the S/Fe-poor sub-group seemingly reflects nebular fractionation only. Highly mobile In and Zn apparently reflect shock-induced loss from L-chondrites. Data for L5 chondrites suggest higher formation temperatures and/or degrees of shock than for LL5 chondrites.

  16. Chemical studies of L-chondrites. I - A study of possible chemical sub-groups

    NASA Technical Reports Server (NTRS)

    Neal, C. W.; Dodd, R. T.; Jarosewich, E.; Lipschutz, M. E.

    1981-01-01

    Radiochemical neutron activation analysis of Ag, As, Au, Bi, Co, Cs, Ga, In, Rb, Sb, Te, Tl and Zn and major element data in 14 L4-6 and 3 LL5 chondrites indicates that the L-group is unusually variable and may represent at least 2 sub-groups differing in formation history. Chemical trends in the S/Fe-rich sub-group support textural evidence indicating late loss of a shock-formed Fe-Ni-S melt; the S/Fe-poor sub-group seemingly reflects nebular fractionation only. Highly mobile In and Zn apparently reflect shock-induced loss from L-chondrites. Data for L5 chondrites suggest higher formation temperatures and/or degrees of shock than for LL5 chondrites.

  17. US Army Chemical Corps Vietnam veterans health study: preliminary results.

    PubMed

    Kang, H K; Dalager, N A; Needham, L L; Patterson, D G; Matanoski, G M; Kanchanaraksa, S; Lees, P S

    2001-01-01

    The long-term health consequences of exposure to phenoxyherbicides used in Vietnam has been a great concern to the veterans. In addition to the Air Force Ranch Hand personnel, Army Chemical Corps personnel who served in Vietnam are thought to have had some of the highest herbicide exposures. The Department of Veterans Affairs commenced a study of veterans who served in Vietnam as members of the Army Chemical Corps and a comparison cohort of Army Chemical Corps personnel who served elsewhere. A total of 2872 Vietnam veterans and 2737 non-Vietnam veterans who served in the Army Chemical Corps were identified for inclusion in a telephone health interview survey with a random 20% sample of veterans receiving serum dioxin and other congeners assessments. In a feasibility study which included 284 Vietnam veterans and 281 non-Vietnam veterans, 100 serum assessments were conducted of which 95 were included in the analysis. Vietnam veterans with a history of spraying herbicides were found to have a statistically significant elevation in their current serum 2,3,7,8-TCDD concentrations compared to non-Vietnam veterans without a spray history (P = 0.05). Other 2,3,7,8-substituted dioxins levels were comparable to the levels found in the non-Vietnam veterans. This feasibility study demonstrated that serum dioxin concentrations from a sample of the study participants can be used to identify exposure variables in the health survey that can serve as a surrogate measure of phenoxyherbicide exposure. PMID:11372888

  18. [Scanning electron microscope study of chemically disinfected endodontic files].

    PubMed

    Navarro, G; Mateos, M; Navarro, J L; Canalda, C

    1991-01-01

    Forty stainless steel endodontic files were observed at scanning electron microscopy after being subjected to ten disinfection cycles of 10 minutes each one, immersed in different chemical disinfectants. Corrosion was not observed on the surface of the files in circumstances that this study was made. PMID:1659857

  19. Novel Diubiquitin Probes Expand the Chemical Toolkit to Study DUBs.

    PubMed

    Kulathu, Yogesh

    2016-04-21

    Linkage-specific DUBs employ different mechanisms to recognize and cleave polyubiquitin chains of specific linkage types. In this issue of Cell Chemical Biology, Flierman et al. (2016) develop a new family of novel non-hydrolyzable diubiquitin probes that will be valuable tools to study how DUBs achieve specificity. PMID:27105279

  20. Laboratory Studies of Heterogeneous Chemical Processes of Atmospheric Importance

    NASA Technical Reports Server (NTRS)

    Molina, Mario J.

    2004-01-01

    The objective of this study is to conduct measurements of chemical kinetics parameters for heterogeneous reactions of importance in the stratosphere and the troposphere. It involves the elucidation of the mechanism of the interaction of HCl vapor with ice surfaces, which is the first step in the heterogeneous chlorine activation processes, as well as the investigation of the atmospheric oxidation mechanism of soot particles emitted by biomass and fossil fuels. The techniques being employed include turbulent flow-chemical ionization mass spectrometry and optical ellipsometry, among others.

  1. Chemical and preclinical studies on Hedyotis diffusa with anticancer potential.

    PubMed

    Niu, Yu; Meng, Qiu-Xia

    2013-01-01

    This paper presents the chemical and preclinical anticancer research on Hedyotis diffusa Willd. in detail, one of the most renowned herbs often prescribed in the polyherbal formulas for cancer treatment in traditional Chinese medicine. Anthraquinones, flavonoids, and terpenoids constitute the majority of the 69 compounds that have been isolated and identified from H. diffusa. The anticancer effects of the methanolic, ethanolic, and aqueous extracts in various preclinical cancer models have been described. This review also summarized the anticancer activity of constituents of the herb and the mechanisms of action. All the studies suggest that H. diffusa has enormous potential in the therapy of cancer and warrants further chemical and pharmacological investigation. PMID:23600735

  2. [An experimental study of chemical necrectomy in chemical injuries of the skin].

    PubMed

    Troshev, K; Markov, D; Skerlev, M

    1993-01-01

    The authors studied experimentally the morphological changes of injuries and the surrounding areas after a skin chemical injury caused by sodium hydroxide, sulphuric acid and chlorhydric acid under the influence of acidic necrolytics--40% benzoic acid and 40% salycilic acid in unguentus. The necrolytics are applied on the injured areas immediately upon getting the wound or on the 4th day thereafter, while the morphological study is carried out after getting off the necrosis. It has been established that the necrolysis in the case of sodium hydroxide was not effected by the 28th day. The processes in the tissues upon acidic injuries do not differ from the spontaneous healing process. PMID:8264193

  3. Abatement of sulfur hexafluoride emissions from the semiconductor manufacturing process by atmospheric-pressure plasmas.

    PubMed

    Lee, How Ming; Chang, Moo Been; Wu, Kuan Yu

    2004-08-01

    Sulfur hexafluoride (SF6) is an important gas for plasma etching processes in the semiconductor industry. SF6 intensely absorbs infrared radiation and, consequently, aggravates global warming. This study investigates SF6 abatement by nonthermal plasma technologies under atmospheric pressure. Two kinds of nonthermal plasma processes--dielectric barrier discharge (DBD) and combined plasma catalysis (CPC)--were employed and evaluated. Experimental results indicated that as much as 91% of SF6 was removed with DBDs at 20 kV of applied voltage and 150 Hz of discharge frequency for the gas stream containing 300 ppm SF6, 12% oxygen (O2), and 40% argon (Ar), with nitrogen (N2) as the carrier gas. Four additives, including Ar, O2, ethylene (C2H4), and H2O(g), are effective in enhancing SF6 abatement in the range of conditions studied. DBD achieves a higher SF6 removal efficiency than does CPC at the same operation condition. But CPC achieves a higher electrical energy utilization compared with DBD. However, poisoning of catalysts by sulfur (S)-containing species needs further investigation. SF6 is mainly converted to SOF2, SO2F4, sulfur dioxide (SO2), oxygen difluoride (OF2), and fluoride (F2). They do not cause global warming and can be captured by either wet scrubbing or adsorption. This study indicates that DBD and CPC are feasible control technologies for reducing SF6 emissions. PMID:15373364

  4. Chemical study of the Chinese medicine Pi Han Yao

    PubMed Central

    PENG, TENG; ZHAO, FURONG; CHEN, XIAOYU; JIANG, GUIHUA; WANG, SHAONAN

    2016-01-01

    The aim of the present study was to ivnestigate the chemical constituents of the Chinese medicine Pi Han Yao (Gueldenstaedtia delavayi Franch) decoction. Following this, the quantitative determination of the formononetin and maackiain content in Pi Han Yao was established. The chemical constituents were isolated by column chromatography and their structures were elucidated by analysis of spectrometric data and chemical evidence. High-performance liquid chromatography (HPLC) was used for the determination of the formononetin and maackiain content in Pi Han Yao. Seven flavanones were isolated from the Pi Han Yao decoction. Five of the chemical structures were elucidated as 1, 7,2′-dihydroxy-4′-methoxy-isoflavanol; 2, maackiain; 3, formononetin-7-O-β-D-glucoside; 4, formononetin; and 5, 9-(β-D-ribofuranosyl)-adenosine. The other two compounds and their structures require further study. Additionally, the linear range of formononetin and maackiain were 0.03992–0.3992 and 0.0292–0.292 µg, and their recoveries were 100.31 and 100.44%. To the best of our knowledge, compounds 1–5 were obtained from Pi Han Yao for the first time. The HPLC method use for determination of formononetin and maackiain in Pi Han Yao was simple, accurate and reliable. Findings from the present study suggest that these methods may be used to evaluate the quality of Pi Han Yao and provide an experience basis for quality standards of this medicinal material. PMID:26893842

  5. CATAWISSA CREEK MINE DRAINAGE ABATEMENT PROJECT

    EPA Science Inventory

    The objective of this study was to determine the feasibility of flooding underground coal mine workings in an isolated basin of coal, thereby restoring or partially restoring the groundwater table in the basin and reducing the production of acid mine drainage. Flooding the mined ...

  6. Noise exposure assessment and abatement strategies at an indoor firing range.

    PubMed

    Kardous, Chucri A; Willson, Robert D; Hayden, Charles S; Szlapa, Piotr; Murphy, William J; Reeves, Efrem R

    2003-08-01

    Exposure to hazardous impulse noise is common during the firing of weapons at indoor firing ranges. The aims of this study were to characterize the impulse noise environment at a law enforcement firing range; document the insufficiencies found at the range from a health and safety standpoint; and provide noise abatement recommendations to reduce the overall health hazard to the auditory system. Ten shooters conducted a typical live-fire exercise using three different weapons--the Beretta.40 caliber pistol, the Remington.308 caliber shotgun, and the M4.223 caliber assault rifle. Measurements were obtained at 12 different positions throughout the firing range and adjacent areas using dosimeters and sound level meters. Personal and area measurements were recorded to a digital audio tape (DAT) recorder for further spectral analysis. Peak pressure levels inside the firing range reached 163 decibels (dB) in peak pressure. Equivalent sound levels (Leq) ranged from 78 decibels, A-weighted (dBA), in office area adjacent to the range to 122 dBA inside the range. Noise reductions from wall structures ranged from 29-44 dB. Noise abatement strategies ranged from simple noise control measures (such as sealing construction joints and leaks) to elaborate design modifications to eliminate structural-borne sounds using acoustical treatments. Further studies are needed to better characterize the effects of firing weapons in enclosed spaces on hearing and health in general. PMID:12851012

  7. A Preliminary Study for Chemical Ranking System in Terms of Soil and Groundwater Contamination by Chemical Accidents

    NASA Astrophysics Data System (ADS)

    Park, J.; Jeong, Y. C.; Kim, K. E.; Lee, D.; Yoo, K.; Kim, J.; Hwang, S.

    2015-12-01

    A variety of chemicals could affect human health and ecosystems by chemical accidents such as fire, explosion, and/or spill. Chemical accidents make chemicals spread to the environment via various routes such as dispersion into ambient air, soil, and surface/ground water media. Especially, soil and groundwater contamination by chemical accidents become a secondary source to have a long term effect on human health and environment. Strength of long term effect by soil and groundwater contamination depends largely on inherent characteristics of a chemical and its fate in soil and groundwater. Therefore, in this study, we developed a framework on how to determine what kind of chemicals is more important in management scheme in terms of soil and groundwater contamination during chemical accidents. We ranked approximately fifty chemicals using this framework which takes into account an exposure into soil and groundwater, toxicity, persistence, and bioaccumulation of a chemical. This framework helps to prepare systematically the management plan for chemical related facilities. Furthermore, results from our study can make a policy maker have interests in highly ranked chemicals and facilities.

  8. Noise-abatement method for explosives testing

    SciTech Connect

    Pfeifer, H.E.; Odell, B.N.; Arganbright, V.E.

    1980-09-01

    When Lawrence Livermore Labortory started detonating explosives at its Site 300 test location in the sparsely populated hills east of the Laboratory, residents in neighboring areas complained of sudden loud noises. A combined literature and research study, coupled with an experimental test program, indicated the combination of air temperatures and winds at various elevations was primarily responsible for blast or sound waves being returned to the surface. To solve the noise problem, the Laboratory devised a method for determining the maximum amount of explosives that could be detonated aboveground under various atmospheric conditions without creating excessive noise in populated areas. This method for predicting explosives weight limits using pressure-distance-weight nomograms and the slope of a sound-velocity curve is described. The sound-velocity curve is computed with temperature information from the US Weather Bureau and wind data from a target-acquisition radar system. By following this method, the Laboratory has been able to detonate thousands of shots without creating excessive noise in nearby communities.

  9. Noise-abatement method for explosives testing.

    PubMed

    Pfeifer, H E; Odell, B N; Arganbright, V E

    1980-09-01

    When Lawrence Livermore Laboratory started detonating explosives at its Site 300 test location in the sparsely populated hills east of the Laboratory, residents in neighboring areas complained of sudden loud noises. A combined literature and research study, coupled with an experimental test program, indicated the combination of air temperatures and winds at various elevations was primarily responsible for blast or sound waves being returned to the surface. To solve the noise problem, the Laboratory devised a method for determining the maximum amount of explosives that could be detonated aboveground under various atmospheric conditions without creating excessive noise in populated areas. This method for predicting explosives weight limits using pressure-distance-weight nomograms and the slope of a sound-velocity curve is described in this paper. The sound-velocity curve is computed with temperature information from the U.S. Weather Bureau and wind data from a target-acquisition radar system. By following this method, the Laboratory has been able to detonate thousands of shots without creating excessive noise in nearby communities. PMID:7457390

  10. A Descriptive Analysis of the Chemical Bond Approach, the Chemical Education Material Study, and a Representative Traditional Chemistry Course.

    ERIC Educational Resources Information Center

    Crilly, Alice Roth

    This study compared three one-year courses in high school chemistry. One of these, entitled Modern Chemistry, represents the "traditional" precollegiate chemistry course. The others are the Chemical Bond Approach (CBA) and the Chemical Education Material Study (CHEM Study). These are the two major revisions in high school chemistry which emerged…

  11. Essays on carbon abatement and electricity markets

    NASA Astrophysics Data System (ADS)

    Taber, John Timothy

    In the first chapter of this dissertation, I study the effects of a number of policies which affect the electric grid using the SuperOPF, a full AC optimization/simulation framework with optimal investment developed at Cornell University. A 36-node model of the Northeast Power Coordinating Council is used to test policies that aim to reduce CO2, other emissions, or otherwise impact the operation of the electric grid: a base case, with no new environmental legislation; enactment of the Kerry-Lieberman CO2 allowance proposal in 2012; following Fukishima, a retirement of all US nuclear plants by 2022 with and without Kerry-Lieberman; marginal damages from SO2 and NOX emissions charged to coal, gas and oil-fired generation; plug-in hybrid electric vehicle load filling; wind incentives in place; and two cases which combine these. The cases suggest that alternative policies may have very different outcomes in terms of electricity prices, emissions, and health outcomes. In all cases, however, the optimal strategy for future investment is investment in new natural gas combined cycle plants. Policies can change how much new generation is built, whether other plants are built, or what types of plants are retired. The second chapter of my dissertation utilizes the SuperOPF and the model of the Northeast Power Coordinating Council to analyze the issue of carbon leakage. I analyze the effects of a regionally-limited carbon cap and trade program, the Regional Greenhouse Initiative (RGGI), when additional generating assets in non-affected states are included in the analysis. In the face of different carbon prices on generating assets in covered and non-covered states, generation is expected to shift from states bound by RGGI to states outside of RGGI. This carbon leakage may undermine some or all of the benefits of RGGI while simultaneously increasing prices for customers in the area. Even though carbon prices under RGGI are very low, some leakage is occurring, and this leakage

  12. Hexane abatement and spore emission control in a fungal biofilter-photoreactor hybrid unit.

    PubMed

    Saucedo-Lucero, J O; Quijano, G; Arriaga, S; Muñoz, R

    2014-07-15

    The performance of a fungal perlite-based biofilter coupled to a post-treatment photoreactor was evaluated over 234 days in terms of n-hexane removal, emission and deactivation of fungal spores. The biofilter and photoreactor were operated at gas residence times of 1.20 and 0.14min, respectively, and a hexane loading rate of 115±5gm(-3)h(-1). Steady n-hexane elimination capacities of 30-40gm(-3)h(-1) were achieved, concomitantly with pollutant mineralization efficiencies of 60-90%. No significant influence of biofilter irrigation frequency or irrigation nitrogen concentration on hexane abatement was recorded. Photolysis did not support an efficient hexane post-treatment likely due to the short EBRT applied in the photoreactor, while overall hexane removal and mineralization enhancements of 25% were recorded when the irradiated photoreactor was packed with ZnO-impregnated perlite. However, a rapid catalyst deactivation was observed, which required a periodic reactivation every 48h. Biofilter irrigation every 3 days supported fungal spore emissions at concentrations ranging from 2.4×10(3) to 9.0×10(4)CFUm(-3). Finally, spore deactivation efficiencies of ≈98% were recorded for the photolytic and photocatalytic post-treatment processes. This study confirmed the potential of photo-assisted post-treatment processes to mitigate the emission of hazardous fungal spores and boost the abatement performance of biotechnologies. PMID:24887128

  13. Demolition Range Noise Abatement Technique Demonstration and Evaluation for the McAlester Army Ammunition Plant

    SciTech Connect

    CALDERONE,JAMES J.; GARBIN,H. DOUGLAS

    2001-08-01

    Public concern regarding the effects of noise generated by the detonation of excess and obsolete explosive munitions at U.S. Army demolition ranges is a continuing issue for the Army's demilitarization and disposal groups. Recent concerns of citizens living near the McAlester Army Ammunition Plant (MCAAP) in Oklahoma have lead the U.S. Army Defense Ammunition Center (DAC) to conduct a demonstration and evaluation of noise abatement techniques that could be applied to the MCAAP demolition range. With the support of the DAC, MCAAP, and Sandia National Laboratories (SNL), three types of noise abatement techniques were applied: aqueous foams, overburden (using combinations of sand beds and dirt coverings), and rubber or steel blast mats. Eight test configurations were studied and twenty-four experiments were conducted on the MCAAP demolition range in July of 2000. Instrumentation and data acquisition systems were fielded for the collection of near-field blast pressures, far-field acoustic pressures, plant boundary seismic signals, and demolition range meteorological conditions. The resulting data has been analyzed and reported, and a ranking of each technique's effects has been provided to the DAC.

  14. {open_quotes}BIOX{close_quotes} hydrogen sulfide abatement process - application analysis

    SciTech Connect

    Gallup, D.L.

    1996-12-31

    A new hydrogen sulfide abatement process, known as {open_quotes}BIOX,{close_quotes} has been specifically developed for the geothermal industry. {open_quotes}BIOX{close_quotes} (biocide induced oxidation) successfully controls both primary and secondary emissions from cooling towers in pilot, demonstration, and commercial operations by air-wet oxidation. Independent laboratory tests recently controverted the efficacy of {open_quotes}BIOX{close_quotes} to catalytically oxidize sulfides to sulfate. Studies conducted in our laboratory with a simulated cooling tower indicate that the experimental conditions employed by Nardini, et al, are unrealistic for geothermal cooling towers. Furthermore, our investigations demonstrate that the {open_quotes}BIOX{close_quotes} process performs optimally at near neutral pH, a condition common to most geothermal cooling tower circulating water systems. A {open_quotes}BIOX{close_quotes} agent, trichloroisocyanuric acid (TCCA), proved to mitigate sulfide emissions much more efficiently than air, sodium hypochlorite or chlorine dioxide. {open_quotes}BIOX{close_quotes} is a proven, cost-effective H{sub 2}S abatement technology.

  15. A decontamination study of simulated chemical and biological agents

    NASA Astrophysics Data System (ADS)

    Uhm, Han S.; Lee, Han Y.; Hong, Yong C.; Shin, Dong H.; Park, Yun H.; Hong, Yi F.; Lee, Chong K.

    2007-07-01

    A comprehensive decontamination scheme of the chemical and biological agents, including airborne agents and surface contaminating agents, is presented. When a chemical and biological attack occurs, it is critical to decontaminate facilities or equipments to an acceptable level in a very short time. The plasma flame presented here may provide a rapid and effective elimination of toxic substances in the interior air in isolated spaces. As an example, a reaction chamber, with the dimensions of a 22cm diameter and 30cm length, purifies air with an airflow rate of 5000l/min contaminated with toluene, the simulated chemical agent, and soot from a diesel engine, the simulated aerosol for biological agents. Although the airborne agents in an isolated space are eliminated to an acceptable level by the plasma flame, the decontamination of the chemical and biological agents cannot be completed without cleaning surfaces of the facilities. A simulated sterilization study of micro-organisms was carried out using the electrolyzed ozone water. The electrolyzed ozone water very effectively kills endospores of Bacillus atrophaeus (ATCC 9372) within 3min. The electrolyzed ozone water also kills the vegetative micro-organisms, fungi, and virus. The electrolyzed ozone water, after the decontamination process, disintegrates into ordinary water and oxygen without any trace of harmful materials to the environment.

  16. A decontamination study of simulated chemical and biological agents

    SciTech Connect

    Uhm, Han S.; Lee, Han Y.; Hong, Yong C.; Shin, Dong H.; Park, Yun H.; Hong, Yi F.; Lee, Chong K.

    2007-07-01

    A comprehensive decontamination scheme of the chemical and biological agents, including airborne agents and surface contaminating agents, is presented. When a chemical and biological attack occurs, it is critical to decontaminate facilities or equipments to an acceptable level in a very short time. The plasma flame presented here may provide a rapid and effective elimination of toxic substances in the interior air in isolated spaces. As an example, a reaction chamber, with the dimensions of a 22 cm diameter and 30 cm length, purifies air with an airflow rate of 5000 l/min contaminated with toluene, the simulated chemical agent, and soot from a diesel engine, the simulated aerosol for biological agents. Although the airborne agents in an isolated space are eliminated to an acceptable level by the plasma flame, the decontamination of the chemical and biological agents cannot be completed without cleaning surfaces of the facilities. A simulated sterilization study of micro-organisms was carried out using the electrolyzed ozone water. The electrolyzed ozone water very effectively kills endospores of Bacillus atrophaeus (ATCC 9372) within 3 min. The electrolyzed ozone water also kills the vegetative micro-organisms, fungi, and virus. The electrolyzed ozone water, after the decontamination process, disintegrates into ordinary water and oxygen without any trace of harmful materials to the environment.

  17. Study of interfacial phenomena for bio/chemical sensing applications

    NASA Astrophysics Data System (ADS)

    Min, Hwall

    This work presents the fundamental study of biological and chemical interfacial phenomena and (bio)chemical sensing applications using high frequency resonator arrays. To realize a versatile (bio)chemical sensing system for the fundamental study as well as their practical applications, the following three distinct components were studied and developed: i) detection platforms with high sensitivity, ii) novel innovative sensing materials with high selectivity, iii) analytical model for data interpretation. 8-pixel micromachined quartz crystal resonator (muQCR) arrays with a fundamental resonance frequency of 60 ¡V 90 MHz have been used to provide a reliable detection platform with high sensitivity. Room temperature ionic liquid (RTIL) has been explored and integrated into the sensing system as a smart chemical sensing material. The use of nanoporous gold (np-Au) enables the combination of the resonator and surface-enhanced Raman spectroscopy for both quantitative and qualitative measurement. A statistical model for the characterization of resonator behavior to study the protein adsorption kinetics is developed by random sequential adsorption (RSA) approach with the integration of an effective surface depletion theory. The investigation of the adsorption kinetics of blood proteins is reported as the fundamental study of biological phenomena using the proposed sensing system. The aim of this work is to study different aspects of protein adsorption and kinetics of adsorption process with blood proteins on different surfaces. We specifically focus on surface depletion effect in conjunction with the RSA model to explain the observed adsorption isotherm characteristics. A number of case studies on protein adsorption conducted using the proposed sensing system has been discussed. Effort is specifically made to understand adsorption kinetics, and the effect of surface on the adsorption process as well as the properties of the adsorbed protein layer. The second half of the

  18. Abatement of indoor air pollution achieved with coal-biomass household briquettes

    NASA Astrophysics Data System (ADS)

    Yamada, Kimiko; Sorimachi, Atsuyuki; Wang, Qingyue; Yi, Jing; Cheng, Shuqun; Zhou, Yanrong; Sakamoto, Kazuhiko

    We investigated the abatement of indoor pollution achieved when two types of coal-biomass briquettes (L-BBs and H-BBs) were used in place of honeycombed coal briquettes (H-coal) in household stoves in rural Chongqing, China. Indoor concentrations of sulfur dioxide (SO 2), carbon monoxide (CO), and gaseous fluoride were measured. Additionally, we evaluated the factors that affected indoor concentrations of these gases, including the amount of fuel used as well as its sulfur content, the sulfur-emission ratio determined from the amount of sulfur retained in the combustion ash, and the combustion temperature in the stoves. The average 8-h and 24-h SO 2 concentrations for L-BBs were nearly equal to or less than the World Health Organization's 40 ppb guideline, whereas those for H-coal and H-BBs exceeded the guideline. The average 8-h SO 2 concentrations for L-BBs were from 63 to 89% lower than those for H-coal, even though the 8-h average weight of fuel and its sulfur content for L-BBs were equal to those of H-coal. A chemical analysis of combustion ash indicated that the sulfur-emission ratio was from 26 to 48% for L-BBs, as compared with 86% for H-coal, and this difference resulted in reduction of indoor SO 2 concentrations for L-BBs as compared with H-coal. Most of the 8-h average concentrations of CO and gaseous fluoride for all fuels were lower than the WHO guidelines. We concluded that BBs are a useful domestic fuel for the abatement of indoor air pollution.

  19. Computational Study on Chemical Reaction Mechanisms of Octafluorocarbon Molecules

    NASA Astrophysics Data System (ADS)

    Choi, Heechol; Song, Mi-Young; Yoon, Jung-Sik; Plasma Fundamental Technology Research Team

    2015-09-01

    Saturated or unsaturated octafluorocarbons(OFCs) have been used extensively in dry etching processes due to their relatively low global warming potential and their high CF2 radical levels in commercial plasma treatments. Many experimental and theoretical studies of these species have been performed for useful information about physical and chemical properties of OFCs. However, direct experimental studies of these chemicals are difficult because of their high reactivity in plasma state and high-level theoretical approaches such as G3(MP2) and CCSD(T)/CBS need huge computational cost. Recently, it has been shown that the ωB97X-D/aVTZ method is strongly recommended as the best practical density functional theory(DFT) for rigorous and extensive studies of OFCs because of its high performance and reliability for van der Waals interactions. All the feasible isomerization and dissociation paths of OFCs were investigated at ωB97X-D/aVTZ and rate constants of their chemical reactions were computed by using variational transition-state theory(VTST) for a deep insight into OFCs' reaction mechanisms. Fates and roles of OFCs and their fragments in plasma phases could be clearly explained based on the obtained reaction mechanisms. This work was supported by R&D Program of ``Plasma Convergence & Fundamental Research'' through NFRI of Korea funded by the Government funds.

  20. Chemical composition studies of flint with different origins

    NASA Astrophysics Data System (ADS)

    Zarina, Liga; Seglins, Valdis; Kostjukovs, Juris; Burlakovs, Juris

    2015-04-01

    Flint is a widely used material in the Stone Age because of its physical characteristics, which makes the material suitable for obtaining tools with sharp working edges. Chert, flint, chalcedony, agate and jasper in composition and several other physical characteristics are very similar. Therefore in archaeology most often they are determined simplified and are not distinguished, but described as flint or chert, denoting only the material in a general sense. However, in-depth studies it is necessary accurately identify the rock type and, in addition, to determine the origin of the flint and the conditions of the formation for the various archaeological research needs. As a typical example can be noted the localization problems in determining whether flint is local, or have emerged in the region through the exchange or by transportation. Flint consists mainly from quartz and mostly it has cryptocrystalline or amorphous structure. In nature it occurs as nodules and interbedded inclusions in sedimentary deposits as a result of digenesis processes when calcium carbonate is replaced with silicia. Bedded chert primarily is accumulations originated from excess alkalinity in the sediments. Flint can also be formed in the crystallization processes of the chemically unstable amorphous silicia. In this context, it should be noted that flint is naturally heterogeneous and very varied material by the physical properties and therefore problematic in many contemporary studies. In the study different origin flint samples from England, Denmark and Latvia were compared after their chemical composition. Flint nodules from Northern Europe chalk cliffs formed as inclusions in interbedded deposits or results of the digenesis and samples of chalcedony saturated dolomite from Latvia formed in hydrothermal processes were analysed using XRD and XRF methods. The obtained data were statistically analysed, identifying major, minor and trace elements and subsequently assessing the chemical

  1. Physico-Chemical profile of Puga Khanda: A Preliminary Study

    PubMed Central

    Baragi, Pramod C.; Baragi, Umapati C.; Bhat, Sathyanarayana; Prajapati, Pradeep Kumar

    2014-01-01

    Background: Herbal medicines are the oldest known form of medicine in the world. However, the quality control and the assurance still remains a challenge because of the high variability of chemical components. Herbal drugs, singlely or in combinations, contain numerous compounds in complex matrices in which no single active constituent is responsible for the overall efficacy. This creates a challenge in establishing quality control standards and the standardization of finished herbal products. Many formulations have been mentioned in Ayurvedic text for Vrushyatwa (aphrodisiac). Puga Khanda is one among such formulations. Aim: To develop preliminary physico-chemical profile of Puga Khanda. Materials and Methods: Puga Khanda was prepared in three batches as per the classical reference mentioned in Bhaishajya Ratnavali. The formulation was subjected for physico-chemical analysis, phytochemical analysis and Thin Layer Chromatography (TLC). Results and Conclusion: The study revealed that organoleptic characters, pH and extractive values of all 3 samples were almost equal. All the samples had 60% of sugar needed for preservation and 2/3rd of it was non reducing sugar. The total alkaloids ranged from 0.002 to 0.004% w/w. In TLC study the entire samples showed similar pattern except the 2nd sample of Puga Khanda. PMID:25364209

  2. Holistic Watershed-Scale Approach for Studying Agricultural Chemicals

    NASA Astrophysics Data System (ADS)

    Capel, P. D.; Domagalski, J. L.

    2006-05-01

    The USGS National Water-Quality Assessment (NAWQA) Program studied the water quality of 51 areas across the United States during its first decade (1991-2001). Analyses of results from that phase of the NAWQA Program indicated that detailed studies of the processes affecting water quality could aid in the interpretation of these data, help to determine the direction and scope of future monitoring studies, and add to the understanding of the sources, transport and fate of non-point source chemicals, such as from agriculture. Now in the second decade of investigations, the NAWQA Program has initiated new process-based detailed studies to increase our understanding at the scale of a small watershed (about 3-15 square kilometers), nested within the larger basins studied during the first decade. The holistic, mass-budget approach for small agricultural watersheds that was adopted includes processes, and measures water and chemicals in the atmosphere, surface water, tile drains, overland flow, and within various sub-surface environments including the vadose, saturated, and hyporheic zones. The primary chemicals of interest were nutrients (nitrogen and phosphorous), the triazine and acetanilide herbicides, and the organophosphorus insecticides. Extensive field observations were made, and numerical models were developed to simulate important environmental compartments and interfaces associated with the transport and fate of agricultural chemicals. It is well recognized that these field measurements and simulations cannot fully achieve a full mass budget at this scale, but the approach provides a useful means for comparisons of various processes in different environmental settings. The results gained using this approach will add to the general knowledge of environmental transport and fate processes, and have transfer value to unstudied areas and different scales of investigation. The five initial study areas started in 2002, included watersheds in California, Indiana

  3. Oak Ridge National Laboratory Biological Monitoring and Abatement Program for White Oak Creek Watershed and the Clinch River

    SciTech Connect

    Loar, J.M.; Adams, S.M.; Allison, L.J.; Blaylock, B.G.; Boston, H.L.; Huston, M.A.; Kimmel, B.L.; Smith, J.G.; Southworth, G.R.; Stewart, A.J.; Walton, B.T.; Kitchings, J.T.; Olsen, C.R.

    1991-09-01

    On April 1, 1986, a National Pollutant Discharge Elimination System (NPDES) permit was issued for the Oak Ridge National Laboratory (ORNL) (EPA 1986). As specified in Part 3: Special Conditions (Item H) of the permit, a plan for biological monitoring of the Clinch River, White Oak Creek (WOC), Northwest Tributary (NWT) of WOC, Melton Branch (MB), Fifth Creek, and First Creek shall be submitted for approval to the US Environmental Protection Agency (EPA) and the Tennessee Department of Health and Environment (TDHE) within 90 days of the effective date of the permit. The plan, which is referred to in Part 3 (H) of the permit as the Biological Monitoring Plan and Abatement Program (BMPAP), describes characterization monitoring studies to be conducted for the duration of the permit (5 years). In order to be consistent with the terminology used for the Biological Monitoring and Abatement Programs for the Oak Ridge Y-12 Plan and the Oak Ridge K-25 Plant, BMPAP will subsequently be referred to as the Biological Monitoring and Abatement Program (BMAP). The proposed BMAP outlined in this document is based on preliminary discussions held on December 9, 1985, between staff of Martin Marietta Energy Systems, Inc. (ORNL and Central Management), the US Department of Energy (DOE), EPA, and TDHE. 232 refs., 11 figs., 7 tabs.

  4. Laboratory Studies of Heterogeneous Chemical Processes of Atmospheric Importance

    NASA Technical Reports Server (NTRS)

    Molina, Mario J.

    2003-01-01

    The objective of this study is to conduct measurements of chemical kinetics parameters for heterogeneous reactions of importance in the stratosphere and the troposphere. It involves the elucidation of the mechanism of the interaction of HC1 vapor with ice surfaces, which is the first step in the heterogeneous chlorine activation processes, as well as the investigation of the atmospheric oxidation mechanism of soot particles emitted by biomass and fossil fuels. The techniques being employed include turbulent flow- chemical ionization mass spectrometry and optical ellipsometry, among others. The next section summarizes our research activities during the first year of the project, and the section that follows consists of the statement of work for the second year.

  5. A chemical kinetic modeling study of chlorinated hydrocarbon combustion

    SciTech Connect

    Pitz, W.J.; Westbrook, C.K.

    1990-09-05

    The combustion of chloroethane is modeled as a stirred reactor so that we can study critical emission characteristics of the reactor as a function of residence time. We examine important operating conditions such as pressure, temperature, and equivalence ratio and their influence on destructive efficiency of chloroethane. The model uses a detailed chemical kinetic mechanism that we have developed previously for C{sub 3} hydrocarbons. We have added to this mechanism the chemical kinetic mechanism for C{sub 2} chlorinated hydrocarbons developed by Senkan and coworkers. In the modeling calculations, sensitivity coefficients are determined to find which reaction-rate constants have the largest effect on destructive efficiency. 24 refs., 6 figs., 1 tab.

  6. [Study on chemical constituents from seed of Oroxylum indicum].

    PubMed

    Zhai, Xiang-yu; Xiao, Wei; Yang, Biao; Meng, Zhao-qing; Wang, Zhen-zhong; Huang, Wen-zhe; Wang, Kai-jin

    2015-08-01

    Oroxylum indicum was a traditional Chinese medicine. In order to study the chemical constituents from the seed of O. indicum, the chemical constituents of 80% methanol extract of seeds of O. indicum were subjected to chromatography on silica gel, Sephadex LH-20, and preparative HPLC, leading to the isolation of eleven compounds. The structures were identified by various spectroscopic data including ESI-MS, 1H-NMR and 13C-NMR data as oroxin B (1), chrysin (2), baicalein (3), neglectein (4), quercetin-3-O-β-D-galactopy ranoside (5), quercetin-7-O-β-D-glucopyranoside (6), 2α,3β-dihydroxylluPeol (7), lupeol (8), rengyol (9), β-sitostero (10), and stigmasterol (11). Among them, compound 5 were firstly obtained from O. indicum. PMID:26677703

  7. Theoretical Chemical Dynamics Studies of Elementary Combustion Reactions

    SciTech Connect

    Donald L. Thompson

    2006-04-27

    The purpose of this research was the development and application of theoretical/computational methods for accurate predictions of the rates of reactions in many-atom systems. The specific aim was to improve computational methods for studying the chemical dynamics of large, complex systems and to obtain a better understanding of the chemical reactions involving large polyatomic molecules and radicals. The focus was on the development an automatic potential energy surface generation algorithm that takes advantage of high-performance computing environments; e.g., software for rate calculations that direct quantum chemistry codes to produce ab initio predictions of reaction rates and related dynamics quantities. Specifically, we developed interpolative moving least-squares (IMLS) methods for accurately fitting ab initio energies to provide global PESs and for use in direct dynamics simulations.

  8. Historical cohort study of mortality among chemical researchers

    SciTech Connect

    Maher, K.V.; Defonso, L.R.

    1986-03-01

    This historical cohort study examined mortality among 1,510 white male researchers employed from 1950-1959 who handled chemicals. During 1950-1979, 95 deaths were observed, significantly less than the 173.2 predicted by general population rates (SMR = 55). This was due to deficits in overall cancer deaths (SMR = 66), particularly respiratory cancer (SMR = 28), and reduced mortality from circulatory diseases and accidents. Those who had worked directly with chemicals for more than 5 yr and those who had the most hazardous exposures experienced similar low mortality for all causes, all cancers, and respiratory cancer. Although deaths due to digestive cancer were elevated among those with 1-5 yr of work experience, there was no excess among those working more than 5 yr as would be expected from occupational exposure.

  9. The chemical shock tube as a tool for studying high-temperature chemical kinetics

    NASA Technical Reports Server (NTRS)

    Brabbs, Theodore A.

    1986-01-01

    Although the combustion of hydrocarbons is our primary source of energy today, the chemical reactions, or pathway, by which even the simplest hydro-carbon reacts with atmospheric oxygen to form CO2 and water may not always be known. Furthermore, even when the reaction pathway is known, the reaction rates are always under discussion. The shock tube has been an important and unique tool for building a data base of reaction rates important in the combustion of hydrocarbon fuels. The ability of a shock wave to bring the gas sample to reaction conditions rapidly and homogeneously makes shock-tube studies of reaction kinetics extremely attractive. In addition to the control and uniformity of reaction conditions achieved with shock-wave methods, shock compression can produce gas temperatures far in excess of those in conventional reactors. Argon can be heated to well over 10 000 K, and temperatures around 5000 K are easily obtained with conventional shock-tube techniques. Experiments have proven the validity of shock-wave theory; thus, reaction temperatures and pressures can be calculated from a measurement of the incident shock velocity. A description is given of the chemical shock tube and auxiliary equipment and of two examples of kinetic experiments conducted in a shock tube.

  10. Abatement of methane emissions from landfills -- the German way

    SciTech Connect

    Angerer, G.; Kalb, H.

    1996-12-31

    Landfills are a major source of methane. Methane is generated by biological degradation of native organic matter under anaerobic conditions. In Germany one quarter to one third of the total methane emissions into the air originate from landfills for municipal wastes. These emissions amounts to 1.2--1.9 million metric tons annually. Landfills represent the second most important methane source. For stock farming the technical opportunities to reduce methane emissions are limited. Therefore, environmental policy aiming to abate methane emissions focuses on waste management. In Germany the most effective policy instrument for this task is the Third Administrative Provision to the waste framework law. This provision came into operation in 1993 and requires that waste disposed in landfills must be inert. Beginning in the year 2005 the total organic carbon (TOC) content of the waste will be limited to 1--3%. This limit requires a pretreatment of municipal waste, and among the currently available technology options only an incineration is able to fulfill the stipulated criteria. Methane abatement will be further regulated by the new waste law, Cycle Economy and Waste Law.

  11. Introduction to the Biological Monitoring and Abatement Program

    SciTech Connect

    Peterson, Mark J

    2011-01-01

    This paper provides an introduction to a long-term biological monitoring program and the Environmental Management special issue titled Long-term Biological Monitoring of an Impaired Stream: Implications for Environmental Management. The Biological Monitoring and Abatement Program, or BMAP, was implemented to assess biological impairment downstream of U.S. Department of Energy (DOE) facilities in Oak Ridge, Tennessee, beginning in 1985. Several of the unique aspects of the program include its long-term consistent sampling, a focus on evaluating the effectiveness of specific facility abatement and remedial actions, and the use of quantitative sampling protocols using a multidisciplinary approach. This paper describes the need and importance of long-term watershed-based biological monitoring strategies, in particular for addressing long-term stewardship goals at DOE sites, and provides a summary of the BMAP's objectives, spatial and temporal extent, and overall focus. The primary components of the biological monitoring program for East Fork Poplar Creek in Oak Ridge, Tennessee are introduced, as are the additional 9 papers in this Environmental Management special issue.

  12. Styrene emission abatement in a bathtub manufacturing plant

    SciTech Connect

    Niezgodski, D.M.

    1997-12-31

    EPA is moving forward on promulgating the National Emission Standard for Hazardous Air Pollutants (NESHAP-MACT) for the Reinforced Plastics/Composites Source Category which affects styrene emitters like the American Standard plant. While most composites manufacturers are taking a wait and see approach, American Standard realized the need to move foreward with the controls. Styrene has a reputation of being a difficult VOC to abate. Most adsorption technologies shy away from this monomer due to reactions that cause fires. Weatherly refined their treatment of styrene emissions with experience from installations at similar plants in Europe. Weatherly installed a 35,000 scfm concentrator/oxidation Polyad{trademark} system in 1996 at American Standard`s bathtub manufacturing plant in Salem, Ohio. The styrene emissions are captured in the spray booth exhaust and discharged to the Polyad{trademark} system. The system is achieving 93% removal efficiency on the styrene emissions. This paper will describe the Weatherly Polyad{trademark} VOC abatement system at American Standard`s Salem Ohio plant.

  13. Cost of abating greenhouse gas emissions with cellulosic ethanol.

    PubMed

    Dwivedi, Puneet; Wang, Weiwei; Hudiburg, Tara; Jaiswal, Deepak; Parton, William; Long, Stephen; DeLucia, Evan; Khanna, Madhu

    2015-02-17

    We develop an integrated framework to determine and compare greenhouse gas (GHG) intensities and production costs of cellulosic ethanol derived from corn stover, switchgrass, and miscanthus grown on high and low quality soils for three representative counties in the Eastern United States. This information is critical for assessing the cost-effectiveness of utilizing cellulosic ethanol for mitigating GHG emissions and designing appropriate policy incentives to support cellulosic ethanol production nationwide. We find considerable variations in the GHG intensities and production costs of ethanol across feedstocks and locations mostly due to differences in yields and soil characteristics. As compared to gasoline, the GHG savings from miscanthus-based ethanol ranged between 130% and 156% whereas that from switchgrass ranged between 97% and 135%. The corresponding range for GHG savings with corn stover was 57% to 95% and marginally below the threshold of at least 60% for biofuels classified as cellulosic biofuels under the Renewable Fuels Standard. Estimates of the costs of producing ethanol relative to gasoline imply an abatement cost of at least $48 Mg(-1) of GHG emissions (carbon dioxide equivalent) abated and can be used to infer the minimum carbon tax rate needed to induce consumption of cellulosic ethanol. PMID:25588032

  14. Chemical-induced atrial thrombosis in NTP rodent studies.

    PubMed

    Yoshizawa, Katsuhiko; Kissling, Grace E; Johnson, Jo Anne; Clayton, Natasha P; Flagler, Norris D; Nyska, Abraham

    2005-01-01

    Cardiac thrombosis, one of the causes of sudden death throughout the world, plays a principal role in several cardiovascular diseases, such as myocardial infarction and stroke in humans. Data from studies of induction of chemical thrombosis in rodents help to identify substances in our environment that may contribute to cardiac thrombosis. Results for more than 500 chemicals tested in rodents in 2-year bioassays have been published as Technical Reports of the National Toxicology Program (NTP) http://ntp-server.niehs.nih.gov/index. We evaluated atrial thrombosis induced by these chemical exposures and compared it to similarly induced lesions reported in the literature. Spontaneous rates of cardiac thrombosis were determined for control Fischer 344 rats and B6C3F1 mice: 0% in rats and mice in 90-day studies and, in 2-year studies, 0.7% in both genders of mice, 4% in male rats, and 1% in female rats. Incidences of atrial thrombosis were increased in high-dosed groups involving 13 compounds (incidence rate: 20-100%): 2-butoxyethanol, C.I. Direct Blue 15, bis(2-chloroethoxy)methane, diazoaminobenzene, diethanolamine, 3,3'-dimethoxybenzidine dihydrochloride, hexachloroethane, isobutene, methyleugenol, oxazepam, C.I. Pigment Red 23, C.I. Acid Red 114, and 4,4'-thiobis(6-t-butyl-m-cresol). The main localization of spontaneously occurring and chemically induced thromboses occurred in the left atrium. The literature survey suggested that chemical-induced atrial thrombosis might be closely related to myocardial injury, endothelial injury, circulatory stasis, hypercoagulability, and impaired atrial mechanical activity, such as atrial fibrillation, which could cause stasis of blood within the left atrial appendage, contributing to left atrial thrombosis. Supplementary data referenced in this paper are not printed in this issue of Toxicologic Pathology. They are available as downloadable files at http://taylorandfrancis.metapress.com/openurl.asp?genre=journal&issn=0192-6233. To

  15. Adolescents Exiting Homelessness over Two Years: The Risk Amplification and Abatement Model

    ERIC Educational Resources Information Center

    Milburn, Norweeta G.; Rice, Eric; Rotheram-Borus, Mary Jane; Mallett, Shelley; Rosenthal, Doreen; Batterham, Phillip; May, Susanne J.; Witkin, Andrea; Duan, Naihua

    2009-01-01

    The Risk Amplification and Abatement Model (RAAM) demonstrates that negative contact with socializing agents amplify risk, while positive contact abates risk for homeless adolescents. To test this model, the likelihood of exiting homelessness and returning to familial housing at 2 years and stably exiting over time are examined with longitudinal…

  16. 41 CFR 102-80.20 - What are Federal agencies' responsibilities concerning the abatement of radon?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... agencies' responsibilities concerning the abatement of radon? 102-80.20 Section 102-80.20 Public Contracts... REGULATION REAL PROPERTY 80-SAFETY AND ENVIRONMENTAL MANAGEMENT Safety and Environmental Management Radon § 102-80.20 What are Federal agencies' responsibilities concerning the abatement of radon?...

  17. 41 CFR 102-80.20 - What are Federal agencies' responsibilities concerning the abatement of radon?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... agencies' responsibilities concerning the abatement of radon? 102-80.20 Section 102-80.20 Public Contracts... REGULATION REAL PROPERTY 80-SAFETY AND ENVIRONMENTAL MANAGEMENT Safety and Environmental Management Radon § 102-80.20 What are Federal agencies' responsibilities concerning the abatement of radon?...

  18. 30 CFR 75.401 - Abatement of dust; water or water with a wetting agent.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Abatement of dust; water or water with a wetting agent. 75.401 Section 75.401 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Combustible Materials and Rock Dusting § 75.401 Abatement...

  19. 29 CFR 4208.9 - Plan adoption of additional abatement conditions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 9 2013-07-01 2013-07-01 false Plan adoption of additional abatement conditions. 4208.9... Plan adoption of additional abatement conditions. (a) General rule. A plan may by amendment, subject to... actuarial valuation report of the plan. (5) A statement certifying that notice of the adoption of...

  20. 29 CFR 4208.9 - Plan adoption of additional abatement conditions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 9 2010-07-01 2010-07-01 false Plan adoption of additional abatement conditions. 4208.9... Plan adoption of additional abatement conditions. (a) General rule. A plan may by amendment, subject to... actuarial valuation report of the plan. (5) A statement certifying that notice of the adoption of...

  1. 29 CFR 4208.9 - Plan adoption of additional abatement conditions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 9 2012-07-01 2012-07-01 false Plan adoption of additional abatement conditions. 4208.9... Plan adoption of additional abatement conditions. (a) General rule. A plan may by amendment, subject to... actuarial valuation report of the plan. (5) A statement certifying that notice of the adoption of...

  2. 29 CFR 4208.9 - Plan adoption of additional abatement conditions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 9 2011-07-01 2011-07-01 false Plan adoption of additional abatement conditions. 4208.9... Plan adoption of additional abatement conditions. (a) General rule. A plan may by amendment, subject to... actuarial valuation report of the plan. (5) A statement certifying that notice of the adoption of...

  3. 29 CFR 4208.9 - Plan adoption of additional abatement conditions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 9 2014-07-01 2014-07-01 false Plan adoption of additional abatement conditions. 4208.9... Plan adoption of additional abatement conditions. (a) General rule. A plan may by amendment, subject to... actuarial valuation report of the plan. (5) A statement certifying that notice of the adoption of...

  4. 29 CFR 4207.4 - Withdrawal liability payments during pendency of abatement determination.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... establish an escrow account for, the plan that satisfies the requirements of paragraph (b) of this section... withdrawal liability. An employer that applies for abatement and neither provides a bond/escrow nor pays its withdrawal liability payments remains eligible for abatement. (b) Bond/escrow. The bond or escrow allowed...

  5. 29 CFR 4207.4 - Withdrawal liability payments during pendency of abatement determination.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... establish an escrow account for, the plan that satisfies the requirements of paragraph (b) of this section... withdrawal liability. An employer that applies for abatement and neither provides a bond/escrow nor pays its withdrawal liability payments remains eligible for abatement. (b) Bond/escrow. The bond or escrow allowed...

  6. 29 CFR 4208.5 - Withdrawal liability payments during pendency of abatement determination.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... § 4208.5 Withdrawal liability payments during pendency of abatement determination. (a) Bond/Escrow. An... to, or establish an escrow account for, the plan that satisfies the requirements of paragraph (b) of... second consecutive plan year. An employer that applies for abatement and neither provides a...

  7. 29 CFR 4208.5 - Withdrawal liability payments during pendency of abatement determination.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... § 4208.5 Withdrawal liability payments during pendency of abatement determination. (a) Bond/Escrow. An... to, or establish an escrow account for, the plan that satisfies the requirements of paragraph (b) of... second consecutive plan year. An employer that applies for abatement and neither provides a...

  8. Use of an indigenous fish species, Fundulus zebrinus, in a mosquito abatement program: a field comparison with the mosquitofish, Gambusia affinis.

    PubMed

    Nelson, S M; Keenan, L C

    1992-09-01

    Studies were conducted relating mosquito production in small ponds to presence or absence of larvivorous fishes. Data collected showed that native killifish and introduced mosquitofish controlled mosquito larvae at the same level and support the use of indigenous fish species in mosquito abatement programs. PMID:1357089

  9. Numerical study of chemically reacting flows using an LU scheme

    NASA Technical Reports Server (NTRS)

    Shuen, Jian Shun; Yoon, Seokkwan

    1988-01-01

    A new computational fluid dynamic code has been developed for the study of mixing and chemical reactions in the flow fields of ramjets and scramjets. The code employs an implicit finite volume, lower-upper symmetric successive overrelaxation scheme for solving the complete two-dimensional Navier-Stokes equations and species transport equations in a fully-coupled and very efficient manner. The combustion processes are modeled by an 8-species, 14-step finite rate chemistry model whereas turbulence is simulated by a Baldwin-Lomax algebraic model. The validity of the code is demonstrated by comparing the numerical calculations with both experimental data and previous calculations of a cold flow helium injection into a straight channel and premixed hydrogen-air reacting flows in a ramped duct. The code is then used to calculate the mixing and chemical reactions of a hydrogen jet transversely injected into a supersonic airstream. Results are presented describing the flow field, the recirculation regions in front and behind the injector, and the chemical reactions.

  10. A Feasibility Study of H{sub 2}S Abatement by Incineration of Noncondensable Gases in Vented Steam Flow from Davies-State 5206-1 Geothermal Steam Well, Geysers Geothermal Steam Field, Lake County, California

    SciTech Connect

    2006-08-25

    Determine feasibility of using an incineration-type device to accomplish the required reduction in vent steam H{sub 2}S content to meet ICAPCO rules. This approach is to be the only method considered in this feasibility study.

  11. Evaluation and assessment of the efficacy of an abatement strategy in a former lead smelter community, Boolaroo, Australia.

    PubMed

    Harvey, P J; Taylor, M P; Kristensen, L J; Grant-Vest, S; Rouillon, M; Wu, L; Handley, H K

    2016-08-01

    This study examines the recent soil Lead Abatement Strategy (LAS) in Boolaroo, New South Wales, Australia, that was designed to "achieve a reduction in human exposure to lead dust contamination in surface soils". The abatement programme addressed legacy contamination of residential areas following closure of lead smelting operations in 2003 at the Pasminco Cockle Creek Smelter (PCCS). The principal objective of the LAS was to "cap and cover" lead-contaminated soils within the urban environment surrounding the PCCS. Soil lead concentrations of 2500-5000 mg/kg were scheduled for removal and replacement, while concentrations between 1500 and 2500 mg/kg were replaced only under limited circumstances. To date, there has been no industry, government or independent assessment of the clean-up programme that involved >2000 homes in the township of Boolaroo. Thus, by measuring post-abatement soil lead concentrations in Boolaroo, this study addresses this knowledge gap and evaluates the effectiveness of the LAS for reducing the potential for lead exposure. Soil lead concentrations above the Australian residential soil health investigation level value for residential soils (300 mg/kg) were identified at all but one of the residential properties examined (n = 19). Vacuum dust samples (n = 17) from the same homes had a mean lead concentration of 495 mg/kg (median 380 mg/kg). Bio-accessibility testing revealed that lead in household vacuum dust was readily accessible (% bio-accessible) (mean = 92 %, median = 90 %), demonstrating that the risk of exposure via this pathway remains. Assessment of a limited number of properties (n = 8) where pre-abatement soil lead levels were available for comparison showed they were not statistically different to post-abatement. Although the LAS did not include treatment of non-residential properties, sampling of community areas including public sports fields, playgrounds and schools (n = 32) was undertaken to determine the

  12. Using chemical approaches to study selenoproteins - focus on thioredoxin reductases

    PubMed Central

    Hondal, Robert J.

    2009-01-01

    The study of selenocysteine-containing proteins is difficult due to the problems associated with the heterologous production of these proteins. These problems are due to the intricate recoding mechanism used by cells to translate the UGA codon as a sense codon for selenocysteine. The process is further complicated by the fact that eukaryotes and prokaryotes have different UGA recoding machineries. This review focuses on chemical approaches to produce selenoproteins and study the mechanism of selenoenzymes. The use of intein-mediated peptide ligation is discussed with respect to the production of the mammalian selenoenzymes thioredoxin reductase and selenoprotein R, also known as methionine sulfoxide reductase B1. New methods for removing protecting groups from selenocysteine post-synthesis and methods for selenosulfide/diselenide formation are also reviewed. Chemical approaches have also been used to study the enzymatic mechanism of thioredoxin reductase. The approach divides the enzyme into two modules, a large protein module lacking selenocysteine and a small, synthetic selenocysteine-containing peptide. Study of this semisynthetic enzyme has revealed three distinct enzymatic pathways that depend on the properties of the substrate. The enzyme utilizes a macromolecular mechanism for protein substrates, a second mechanism for small molecule substrates and a third pathway for selenium-containing substrates such as selenocystine. PMID:19406205

  13. Relative influence of chemical and non-chemical stressors on invertebrate communities: a case study in the Danube River.

    PubMed

    Rico, Andreu; Van den Brink, Paul J; Leitner, Patrick; Graf, Wolfram; Focks, Andreas

    2016-11-15

    A key challenge for the ecological risk assessment of chemicals has been to evaluate the relative contribution of chemical pollution to the variability observed in biological communities, as well as to identify multiple stressor groups. In this study we evaluated the toxic pressure exerted by >200 contaminants to benthic macroinvertebrates in the Danube River using the Toxic Unit approach. Furthermore, we evaluated correlations between several stressors (chemical and non-chemical) and biological indices commonly used for the ecological status assessment of aquatic ecosystems. We also performed several variation partitioning analyses to evaluate the relative contribution of contaminants and other abiotic parameters (i.e. habitat characteristics, hydromorphological alterations, water quality parameters) to the structural and biological trait variation of the invertebrate community. The results of this study show that most biological indices significantly correlate to parameters related to habitat and physico-chemical conditions, but showed limited correlation with the calculated toxic pressure. The calculated toxic pressure, however, showed little variation between sampling sites, which complicates the identification of pollution-induced effects. The results of this study show that the variation in the structure and trait composition of the invertebrate community are mainly explained by habitat and water quality parameters, whereas hydromorphological alterations play a less important role. Among the water quality parameters, physico-chemical parameters such as suspended solids, nutrients or dissolved oxygen explained a larger part of the variation in the invertebrate community as compared to metals or organic contaminants. Significant correlations exist between some physico-chemical measurements (e.g. nutrients) and some chemical classes (i.e. pharmaceuticals, chemicals related to human presence) which constitute important multiple stressor groups. This study

  14. Study to establish cost projections for production of Redox chemicals

    NASA Technical Reports Server (NTRS)

    Walther, J. F.; Greco, C. C.; Rusinko, R. N.; Wadsworth, A. L., III

    1982-01-01

    A cost study of four proposed manufacturing processes for redox chemicals for the NASA REDOX Energy Storage System yielded favorable selling prices in the range $0.99 to $1.91/kg of chromic chloride, anhydrous basis, including ferrous chloride. The prices corresponded to specific energy storage costs from under $9 to $17/kWh. A refined and expanded cost analysis of the most favored process yielded a price estimate corresponding to a storage cost of $11/kWh. The findings supported the potential economic viability of the NASA REDOX system.

  15. Chemical reactions of As complexation by glutathione: an XAFS study

    NASA Astrophysics Data System (ADS)

    Franco, M. W.; Vasconcelos, I. F.; Modolo, L. V.; Barbosa, F. A. R.

    2016-05-01

    In this study, the chemical reactions between As(III) and As(V) with glutathione, which is a target compound in As biochemistry due to its primordial role in As immobilization and intracellular reduction, in various molar ratios were investigated using As K-edge XAFS spectroscopy. Results showed a gradual substitution of As-O bonds in the coordination of aqueous As(III) and As(V) for three As-S bonds in the As+GSH complex. Moreover, the data showed reduction of As(V) to As(III) prior or concomitant to the As+GSH complex formation.

  16. A Novel Water Delivery System for Administering Volatile Chemicals while Minimizing Chemical Waste in Rodent Toxicity Studies

    EPA Science Inventory

    Rodent toxicity studies typically use water bottles to administer test chemicals via drinking water. However, water bottles provide inconsistent exposure of volatile chemicals due to varying headspace, as well as lead to excessive waste of test material. In order to refine drin...

  17. Integrated geophysical and chemical study of saline water intrusion.

    PubMed

    Choudhury, Kalpan; Saha, D K

    2004-01-01

    Surface geophysical surveys provide an effective way to image the subsurface and the ground water zone without a large number of observation wells. DC resistivity sounding generally identifies the subsurface formations-the aquifer zone as well as the formations saturated with saline/brackish water. However, the method has serious ambiguities in distinguishing the geological formations of similar resistivities such as saline sand and saline clay, or water quality such as fresh or saline, in a low resistivity formation. In order to minimize the ambiguity and ascertain the efficacy of data integration techniques in ground water and saline contamination studies, a combined geophysical survey and periodic chemical analysis of ground water were carried out employing DC resistivity profiling, resistivity sounding, and shallow seismic refraction methods. By constraining resistivity interpretation with inputs from seismic refraction and chemical analysis, the data integration study proved to be a powerful method for identification of the subsurface formations, ground water zones, the subsurface saline/brackish water zones, and the probable mode and cause of saline water intrusion in an inland aquifer. A case study presented here illustrates these principles. Resistivity sounding alone had earlier failed to identify the different formations in the saline environment. Data integration and resistivity interpretation constrained by water quality analysis led to a new concept of minimum resistivity for ground water-bearing zones, which is the optimum value of resistivity of a subsurface formation in an area below which ground water contained in it is saline/brackish and unsuitable for drinking. PMID:15457790

  18. Matrix isolation as a tool for studying interstellar chemical reactions

    NASA Technical Reports Server (NTRS)

    Ball, David W.; Ortman, Bryan J.; Hauge, Robert H.; Margrave, John L.

    1989-01-01

    Since the identification of the OH radical as an interstellar species, over 50 molecular species were identified as interstellar denizens. While identification of new species appears straightforward, an explanation for their mechanisms of formation is not. Most astronomers concede that large bodies like interstellar dust grains are necessary for adsorption of molecules and their energies of reactions, but many of the mechanistic steps are unknown and speculative. It is proposed that data from matrix isolation experiments involving the reactions of refractory materials (especially C, Si, and Fe atoms and clusters) with small molecules (mainly H2, H2O, CO, CO2) are particularly applicable to explaining mechanistic details of likely interstellar chemical reactions. In many cases, matrix isolation techniques are the sole method of studying such reactions; also in many cases, complexations and bond rearrangements yield molecules never before observed. The study of these reactions thus provides a logical basis for the mechanisms of interstellar reactions. A list of reactions is presented that would simulate interstellar chemical reactions. These reactions were studied using FTIR-matrix isolation techniques.

  19. Regional and sectoral marginal abatement cost curves for NOx incorporating controls, renewable electricity, energy efficiency and fuel switching

    EPA Science Inventory

    A marginal abatement cost curve (MACC) traces out the relationship between the quantity of pollution abated and the marginal cost of abating each additional unit. In the context of air quality management, MACCs typically are developed by sorting end-of-pipe controls by their resp...

  20. Integrated Evaluation of Urban Water Bodies for Pollution Abatement Based on Fuzzy Multicriteria Decision Approach.

    PubMed

    Hashim, Sarfraz; Yuebo, Xie; Saifullah, Muhammad; Nabi Jan, Ramila; Muhetaer, Adila

    2015-01-01

    Today's ecology is erected with miscellaneous framework. However, numerous sources deteriorate it, such as urban rivers that directly cause the environmental pollution. For chemical pollution abatement from urban water bodies, many techniques were introduced to rehabilitate the water quality of these water bodies. In this research, Bacterial Technology (BT) was applied to urban rivers escalating the necessity to control the water pollution in different places (Xuxi River (XXU); Gankeng River (GKS); Xia Zhang River (XZY); Fenghu and Song Yang Rivers (FSR); Jiu Haogang River (JHH)) in China. For data analysis, the physiochemical parameters such as temperature, chemical oxygen demand (COD), dissolved oxygen (DO), total phosphorus (TP), and ammonia nitrogen (NH3N) were determined before and after the treatment. Multicriteria Decision Making (MCDM) method was used for relative significance of different water quality on each station, based on fuzzy analytical hierarchy process (FAHP). The overall results revealed that the pollution is exceeding at "JHH" due to the limit of "COD" as critical water quality parameter and after treatment, an abrupt recovery of the rivers compared with the average improved efficiency of nutrients was 79%, 74%, 68%, and 70% of COD, DO, TP, and NH3N, respectively. The color of the river's water changed to its original form and aquatic living organism appeared with clear effluents from them. PMID:26516623

  1. Integrated Evaluation of Urban Water Bodies for Pollution Abatement Based on Fuzzy Multicriteria Decision Approach

    PubMed Central

    Hashim, Sarfraz; Yuebo, Xie; Saifullah, Muhammad; Nabi Jan, Ramila; Muhetaer, Adila

    2015-01-01

    Today's ecology is erected with miscellaneous framework. However, numerous sources deteriorate it, such as urban rivers that directly cause the environmental pollution. For chemical pollution abatement from urban water bodies, many techniques were introduced to rehabilitate the water quality of these water bodies. In this research, Bacterial Technology (BT) was applied to urban rivers escalating the necessity to control the water pollution in different places (Xuxi River (XXU); Gankeng River (GKS); Xia Zhang River (XZY); Fenghu and Song Yang Rivers (FSR); Jiu Haogang River (JHH)) in China. For data analysis, the physiochemical parameters such as temperature, chemical oxygen demand (COD), dissolved oxygen (DO), total phosphorus (TP), and ammonia nitrogen (NH3N) were determined before and after the treatment. Multicriteria Decision Making (MCDM) method was used for relative significance of different water quality on each station, based on fuzzy analytical hierarchy process (FAHP). The overall results revealed that the pollution is exceeding at “JHH” due to the limit of “COD” as critical water quality parameter and after treatment, an abrupt recovery of the rivers compared with the average improved efficiency of nutrients was 79%, 74%, 68%, and 70% of COD, DO, TP, and NH3N, respectively. The color of the river's water changed to its original form and aquatic living organism appeared with clear effluents from them. PMID:26516623

  2. Chemical reaction and dust formation studies in laboratory hydrocarbon plasmas.

    NASA Astrophysics Data System (ADS)

    Hippler, Rainer; Majumdar, Abhijit; Thejaswini, H. C.

    Plasma chemical reaction studies with relevance to, e.g., Titan's atmosphere have been per-formed in various laboratory plasmas [1,2]. Chemical reactions in a dielectric barrier discharge at medium pressure of 250-300 mbar have been studied in CH4 /N2 and CH4 /Ar gas mixtures by means of mass spectrometry. The main reaction scheme is production of H2 by fragmenta-tion of CH4 , but also production of larger hydrocarbons like Cn Hm with n up to 10 including formation of different functional CN groups is observed. [1] A. Majumdar and R. Hippler, Development of dielectric barrier discharge plasma processing apparatus for mass spectrometry and thin film deposition, Rev. Sci. Instrum. 78, 075103 (2007) [2] H.T. Do, G. Thieme, M. Frühlich, H. Kersten, and R. Hippler, Ion Molecule and Dust Particle Formation in Ar/CH4 , Ar/C2 H2 and Ar/C3 H6 Radio-frequency Plasmas, Contrib. Plasma Phys. 45, No. 5-6, 378-384 (2005)

  3. Combined spectroscopic and quantum chemical studies of ezetimibe

    NASA Astrophysics Data System (ADS)

    Prajapati, Preeti; Pandey, Jaya; Shimpi, Manishkumar R.; Srivastava, Anubha; Tandon, Poonam; Velaga, Sitaram P.; Sinha, Kirti

    2016-12-01

    Ezetimibe (EZT) is a hypocholesterolemic agent used for the treatment of elevated blood cholesterol levels as it lowers the blood cholesterol by blocking the absorption of cholesterol in intestine. Study aims to combine experimental and computational methods to provide insights into the structural and vibrational spectroscopic properties of EZT which is important for explaining drug substance physical and biological properties. Computational study on molecular properties of ezetimibe is presented using density functional theory (DFT) with B3LYP functional and 6-311++G(d,p) basis set. A detailed vibrational assignment has been done for the observed IR and Raman spectra of EZT. In addition to the conformational study, hydrogen bonding and molecular docking studies have been also performed. For conformational studies, the double well potential energy curves have been plotted for the rotation around the six flexible bonds of the molecule. UV absorption spectrum was examined in methanol solvent and compared with calculated one in solvent environment (IEF-PCM) using TD-DFT/6-31G basis set. HOMO-LUMO energy gap of both the conformers have also been calculated in order to predict its chemical reactivity and stability. The stability of the molecule was also examined by means of natural bond analysis (NBO) analysis. To account for the chemical reactivity and site selectivity of the molecules, molecular electrostatic potential (MEPS) map has been plotted. The combination of experimental and calculated results provide an insight into the structural and vibrational spectroscopic properties of EZT. In order to give an insight for the biological activity of EZT, molecular docking of EZT with protein NPC1L1 has been done.

  4. Corrosion study in the chemical air separation (MOLTOX trademark ) process

    SciTech Connect

    Kang, Doohee; Wong, Kai P.; Archer, R.A.; Cassano, A.A.

    1988-12-01

    This report presents the results of studies aimed at solving the corrosion problems encountered during operation of the MOLTOX{trademark} pilot plant. These studies concentrated on the screening of commercial and developmental alloys under conditions simulating operation conditions in this high temperature molten salt process. Process economic studies were preformed in parallel with the laboratory testing to ensure that an economically feasible solution would be achieved. In addition to the above DOE co-funded studies, Air Products and Chemicals pursued proprietary studies aimed at developing a less corrosive salt mixture which would potentially allow the use of chemurgically available alloys such as stainless steels throughout the system. These studies will not be reported here; however, the results of corrosion tests in the new less corrosive salt mixtures are reported. Because our own studies on salt chemistry impacts heavily on the overall process and thereby has an influence on the experimental work conducted under this contract, some of the studies discussed here were impacted by our own proprietary data. Therefore, the reasons behind some of the experiments presented herein will not be explained because that information is proprietary to Air Products. 14 refs., 42 figs., 21 tabs.

  5. Intermittent control procedures for the Geysers hydrogen sulfide emission abatement

    SciTech Connect

    Buick, B.D.; Mooney, M.L.

    1984-01-01

    Pacific Gas and Electric Company (PG and E) operates the world's largest geothermal steam electric power generation facility, currently about 1.140 megawatts (Mw). This facility is located about 80 miles north of San Francisco, California and is within a region referred to as the Known Geothermal Resource Area (KGRA). Pollutants resulting from this method of electric power generation are due to impurities in the geothermal steam. A major contaminate in the steam is hydrogen sulfide (H/sub 2/S), a regulated pollutant in California. The ambient air quality standard (AAQS) for this pollutant in California is 0.03 parts per million (ppM) averaged over one hour. H/sub 2/S is an invisible, unpleasant smelling gas present in varying concentrations in the geothermal steam. Its odor has been compared to the smell of rotten eggs. Since PG and E is increasingly relying on this source of electrical power generation, it has committed millions of dollars to the development, testing, acquisition, and installation of abatement equipment to reduce H/sub 2/S emissions during the past ten years. In order to reduce the number of exceeds of the AAQS during this developmental period, a predictive model was needed for interim abatement purposes. Most of the high hourly H/sub 2/S values occur with meteorological conditions having poor ventilation resulting from a combination of low wind speed and reduced mixing layer depths. This weather condition is most common during the months of June through October in California. A predictive model was developed from three years of hourly H/sub 2/S measurements of 0.03 ppM or greater in populated areas downwind of the generation facility and from observations of associated meteorological data.

  6. RECOVERY OF FISH COMMUNITIES IN A WARMWATER STREAM FOLLOWING POLLUTION ABATEMENT

    SciTech Connect

    Ryon, Michael G

    2011-01-01

    The long-term recovery process for fish communities in a warm water stream in East Tennessee was studied using quantitative measurements over 20 years. The stream receives effluents from a U.S. Department of Energy (DOE) facility, but since 1985 these effluents have been greatly reduced, eliminated, or diluted as part of a substantial long-term pollution abatement program. The resulting changes in water quantity and quality led to a recovery of the fish communities, evidenced by significant changes in species richness, abundance (density and biomass), and community composition (e.g., number of fish species sensitive to stress). The fish community changes occurred over a spatial gradient (downstream from the headwater release zone nearest the DOE facility) and temporally, at multiple sampling locations in the stream. Changes in measured parameters were associated with specific remedial actions and the intervening steps within the recovery process are discussed with regard to changes in treatment processes.

  7. Microbial Sulfate Reduction and Its Potential Utility as an Acid Mine Water Pollution Abatement Procedure

    PubMed Central

    Tuttle, Jon H.; Dugan, Patrick R.; Randles, Chester I.

    1969-01-01

    The presence of high concentrations of sulfate, iron, and hydrogen (acid) ions in drainage from coal mines and other areas containing waste pyritic materials is a serious water pollution problem. Sulfate can be removed from solution by microbial reduction to sulfide and subsequent precipitation as FeS. A mixed culture of microorganisms degraded wood dust cellulose, and the degradation products served as carbon and energy sources for sulfate-reducing bacteria. Metabolism of carbon compounds resulted in a net pH increase in the system. Oxidation-reduction potential (Eh) and temperature and carbon supplements were studied in an effort to accelerate the sulfate reduction process, with the ultimate objective of utilizing the process as a pollution abatement procedure. PMID:5775914

  8. Studies on nonequilibrium phenomena in supersonic chemically reacting flows

    NASA Technical Reports Server (NTRS)

    Tiwari, S. N.; Chandrasekhar, Rajnish

    1993-01-01

    This study deals with a systematic investigation of nonequilibrium processes in supersonic combustion. The two-dimensional, elliptic Navier-Stokes equations are used to investigate supersonic flows with nonequilibrium chemistry and thermodynamics, coupled with radiation, for hydrogen-air systems. The explicit, unsplit MacCormack finite-difference scheme is used to advance the governing equations in time, until convergence is achieved. For a basic understanding of the flow physics, premixed flows undergoing finite rate chemical reactions are investigated. Results obtained for specific conditions indicate that the radiative interactions vary substantially, depending on reactions involving HO2 and NO species, and that this can have a noticeable influence on the flowfield. The second part of this study deals with premixed reacting flows under thermal nonequilibrium conditions. Here, the critical problem is coupling of the vibrational relaxation process with the radiative heat transfer. The specific problem considered is a premixed expanding flow in a supersonic nozzle. Results indicate the presence of nonequilibrium conditions in the expansion region of the nozzle. This results in reduction of the radiative interactions in the flowfield. Next, the present study focuses on investigation of non-premixed flows under chemical nonequilibrium conditions. In this case, the main problem is the coupled turbulence-chemistry interaction. The resulting formulation is validated by comparison with experimental data on reacting supersonic coflowing jets. Results indicate that the effect of heat release is to lower the turbulent shear stress and the mean density. The last part of this study proposes a new theoretical formulation for the coupled turbulence-radiation interactions. Results obtained for the coflowing jets experiment indicate that the effect of turbulence is to enhance the radiative interactions.

  9. Crystallographic Studies of Chemically Modified Nucleic Acids: A Backward Glance

    PubMed Central

    Egli, Martin; Pallan, Pradeep S.

    2010-01-01

    Chemically modified nucleic acids (CNAs) are widely explored as antisense oligonucleotide or small interfering RNA (siRNA) candidates for therapeutic applications. CNAs are also of interest in diagnostics, high-throughput genomics and target validation, nanotechnology and as model systems in investigations directed at a better understanding of the etiology of nucleic acid structure as well as the physical-chemical and pairing properties of DNA and RNA and for probing protein-nucleic acid interactions. In this article we review research conducted by our laboratory over the past two decades with a focus on crystal structure analyses of CNAs and artificial pairing systems. We highlight key insights into issues ranging from conformational distortions as a consequence of modification to the modulation of pairing strength and RNA affinity by stereoelectronic effects and hydration. Although crystal structures have only been determined for a subset of the large number of modifications that were synthesized and analyzed in the oligonucleotide context to date, they have yielded guiding principles for the design of new analogs with tailormade properties, including pairing specificity, nuclease resistance and cellular uptake. And, perhaps less obviously, crystallographic studies of CNAs and synthetic pairing systems have shed light on fundamental aspects of DNA and RNA structure and function that would not have been disclosed by investigations solely focused on the natural nucleic acids. PMID:20087997

  10. Studying Star Clusters as Tracers of the LMC's Chemical Enrichment

    NASA Astrophysics Data System (ADS)

    Palma, T.; Clariá, J. J.; Geisler, D.; Ahumada, A. V.

    2015-05-01

    Based on photometric observations made with the Cerro Tololo Inter-American (CTIO) “Victor Blanco” 4-m telescope, we present the results of a study of the chemical evolution of the Large Magellanic Cloud (LMC) for the last 2.2 Gyr. As tracers of the LMC chemical enrichment, we used 39 star clusters projected on the bar, 27 on the inner disc, and 15 on the outer disc. Our sample includes 44 previously unstudied clusters. In all cases we determined the size, reddening, deprojected distance, age and metallicity. We show that the more metal-rich clusters are mainly located in the inner disc, while more metal-poor clusters are distributed throughout the entire disc. Intermediate-age clusters tend to be located at greater deprojected galactocentric distances while the youngest ones are mainly found in the inner disc. These trends are maintained when the sample is complemented with clusters observed by other authors with the same technique. These results reinforce the idea of the absence of a radial metallicity gradient in the LMC for clusters with subsolar metallicities. The resulting age-metallicity relationship appears to be independent of which LMC region is considered.

  11. Sensitivity study of SMILES-2 for chemical species

    NASA Astrophysics Data System (ADS)

    Suzuki, Makoto; Manago, Naohiro; Ozeki, Hiroyuki; Ochiai, Satoshi; Baron, Philippe

    2015-10-01

    Sensitivity studies of temperature and chemical species (Observed by ISS/JEM/SMILES: O3, HCl, ClO, HO2, BrO, HNO3, CH3CN, and Not observed by SMILES: Temperature, H2O, N2O, NO2, NO, CH3Cl, CO, H2CO, OH and O-atom) was carried out for the SMILES-2 proposal, a sub-mm and THz observation of limb emission from space over the spectral region from 400 GHz to 2.5 THz. Tentative but optimal candidate of frequency bands to cover these species was selected with 3 SIS (Superconductor-Insulator-Superconductor) mixers; SIS-1 (485-489 GHz + 523-527 GHz), SIS-2 (623-627 GHz + 648-652 GHz), SIS-3 (557 GHz + 576.3 GHz) and 2 HEB (Hot Electron Bolometer); HEB-1 (1.8 THz OH) and HEB-2 (2.06 THz O-atom). Temperature can be retrieved with 1 K precision and 1 km vertical resolution from 15 to 120 km. Other chemical species also showed very high single scan precision (random error) comparable to statistical standard error of previous satellite measurements.

  12. Diuretic Properties and Chemical Constituent Studies on Stauntonia brachyanthera

    PubMed Central

    Liu, Xuan Li; Wang, Dan Dan; Wang, Zi Hao; Meng, Da Li

    2015-01-01

    The pharmacological evaluation demonstrated that the extracts from the stem of S. brachyanthera could significantly increase the outputs of urine of rats compared to those of furosemide treated group, and the effect could last for a longer period of time. The best effect appeared in the first two hours, which scientifically confirmed the diuretic effect of the plant. The comparative pharmacognosy study showed that the characters of the crude drugs of the stem of S. brachyanthera were similar to those of Akebia caulis. Further systemic work on its chemical constituents by chromatographic methods and NMR elucidations led to the isolation of 10 triterpenoids, 6 flavonoids, 4 lignanoids, and 3 phenylethanoid glycosides, whose structural types were much similar to those of A. quinata. Among them, 7 compounds were firstly reported in the genus of Stauntonia and calceolarioside B was the common characteristic constituent in both plants. From the similar pharmacognosy characters, pharmacological effects, and chemical constituents, it could be concluded that S. brachyanthera have a great possibility to be a succedaneum of Akebia caulis, whose supply is extremely short in recent years. PMID:27057193

  13. Abatement vs. treatment for efficient diffuse source water pollution management in terrestrial-marine systems.

    PubMed

    Roebeling, P C; Cunha, M C; Arroja, L; van Grieken, M E

    2015-01-01

    Marine ecosystems are affected by water pollution originating from coastal catchments. The delivery of water pollutants can be reduced through water pollution abatement as well as water pollution treatment. Hence, sustainable economic development of coastal regions requires balancing of the marginal costs from water pollution abatement and/or treatment and the associated marginal benefits from marine resource appreciation. Water pollution delivery reduction costs are, however, not equal across abatement and treatment options. In this paper, an optimal control approach is developed and applied to explore welfare maximizing rates of water pollution abatement and/or treatment for efficient diffuse source water pollution management in terrestrial-marine systems. For the case of diffuse source dissolved inorganic nitrogen water pollution in the Tully-Murray region, Queensland, Australia, (agricultural) water pollution abatement cost, (wetland) water pollution treatment cost and marine benefit functions are determined to explore welfare maximizing rates of water pollution abatement and/or treatment. Considering partial (wetland) treatment costs and positive water quality improvement benefits, results show that welfare gains can be obtained, primarily, through diffuse source water pollution abatement (improved agricultural management practices) and, to a minor extent, through diffuse source water pollution treatment (wetland restoration). PMID:26287831

  14. Interior Landscape Plants for Indoor Air Pollution Abatement

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.; Johnson, Anne; Bounds, Keith

    1989-01-01

    In this study, the leaves, roots, soil, and associated microorganisms of plants have been evaluated as a possible means of reducing indoor air pollutants. Additionally, a novel approach of using plant systems for removing high concentrations of indoor air pollutants such as cigarette smoke, organic solvents, and possibly radon has been designed from this work. This air filter design combines plants with an activated carbon filter. The rationale for this design, which evolved from wastewater treatment studies, is based on moving large volumes of contaminated air through an activated carbon bed where smoke, organic chemicals, pathogenic microorganisms (if present), and possibly radon are absorbed by the carbon filter. Plant roots and their associated microorganisms then destroy the pathogenic viruses, bacteria, and the organic chemicals, eventually converting all of these air pollutants into new plant tissue. It is believed that the decayed radon products would be taken up the plant roots and retained in the plant tissue.

  15. Theoretical spectroscopic studies on chemical and electronic structures of arginylglycine.

    PubMed

    Li, Hongbao; Li, Leilei; Jiang, Jun; Lin, Zijing; Luo, Yi

    2015-10-14

    The energy differences between canonical and zwitterionic isomers of arginylglycine (ArgGly) at the CCSD/aug-cc-pVDZ level are too small (less than 1 kcal mol(-1)) to determine the dominant form in the gas phase from the energetic point of view. First-principles simulations have been performed for near-edge X-ray absorption fine-structure (NEXAFS) spectra and X-ray photoelectron spectra (XPS) at C, N and O K-edges, as well as for infrared (IR) spectra of neutral ArgGly. Noticeable spectral differences were found which enable the unambiguous identification of different neutral groups. We thus demonstrate X-ray spectroscopy as a powerful technique to study the conformation dependent chemical and electronic properties of neutral ArgGly. PMID:26266331

  16. Isotopic and chemical studies of early crustal metasedimentary rocks

    NASA Technical Reports Server (NTRS)

    Jacobsen, Stein B.

    1988-01-01

    The aim, within the bounds of the Early Crustal Genesis Project, was the isotopic and chemical study of selected early crustal meta-sedimentary rocks. Western Australia was chosen as the first field area to examine, as the Yilgarn and Pilbara Blocks comprise one of the largest and most varied Precambrian terranes. Furthermore, the Western Gneiss Terrane (on the western flank of the Yilgarn Block) and the Pilbara Block are both non-greenstone in character; these types of terrane were relatively neglected, but are of great significance in the understanding of early crustal meta-sediments. The meta-sediments of aluminous or peraluminous character, commonly also enriched in Mg and/or Fe relative to the more common pelitic meta-sediments, and at many locations, deficient in one or more of the elements Ca, N, and K, were initially chosen.

  17. First quarter chemical borehole studies in the drift scale test

    SciTech Connect

    DeLoach, L., LLNL

    1998-05-19

    The chemistry boreholes of the Drift Scale Test (DST) have been designed to gather geochemical information and assess the impact of thermal perturbations on gas and liquid phases present in pore spaces and fractures within the rock. There are a total of ten boreholes dedicated to these chemical studies. Two arrays of five boreholes each were drilled from the access/observation drift (AOD) in planes which run normal to the heater drift and which are located approximately 15 and 45% of the way along the length of the drift as measured from the bulkhead. The boreholes each have a length of about 40 meters and have been drilled at low angles directed just above or just below the heater plane. In each array, three boreholes are directed at increasingly steeper angles (< 25-) above the line of wing heaters and two are directed at shallow angles below the wing heater plane.

  18. PRELIMINARY STUDY OF METHODS TO CHEMICALLY BIND ZINC

    SciTech Connect

    Korinko, P.

    2011-06-10

    To address the {sup 65}Zn contamination issue in the TEF, a multi-task experimental program was initiated. The first two experimental tasks were completed. The results of the third experimental task are reported here. This task was conducted to determine if the zinc vapors could be chemically bound on two non hydrogen active substrates. Based on a thermodynamic study copper and cobalt were the most favorable for capturing zinc without forming hydrides. Within the experimental parameters tested, which include temperatures of 350, 400, and 450 C at pressures of nominally 20-40 millitorr, the zinc deposited on the both copper screen and cobalt rods but did not react to form a compound. The conditions that were tested are not prototypic and additional testing under higher vacuum conditions, i.e., .01 millitorr, may enhance the reactivity of the surfaces and is recommended.

  19. Spectroscopic and quantum chemical studies on 4-acryloyl morpholine

    NASA Astrophysics Data System (ADS)

    Arjunan, V.; Rani, T.; Santhanalakshmi, K.; Mohan, S.

    2011-09-01

    Fourier transform infrared (FTIR) and FT-Raman spectra have been recorded and an extensive spectroscopic investigations have been carried out on 4-acryloyl morpholine (4AM). Theoretical quantum chemical studies have also been performed. From the ab initio and DFT analysis using HF, B3LYP and B3PW91 methods with 6-31G(d,p) and 6-311G++(d,p) basis sets the energies, structural, thermodynamical and vibrational characteristics of the compound were determined. The energy difference between the chair equatorial and chair axial conformers of 4AM have been calculated by density functional theory (DFT) method. The optimized geometrical parameters, theoretical wavenumbers and thermodynamic properties of the molecule are compared with the experimental values. The effect of acryloyl group on the characteristic frequencies of the morpholine ring has been analysed. The mixing of the fundamental modes with the help of potential energy distribution (PED) through normal co-ordinate analysis has been discussed.

  20. [Study of quantum-pharmacological chemical characteristics of quercetin].

    PubMed

    Zahorodnyĭ, M I

    2007-01-01

    It was established in the previous studies that quercetin prevented the development and caused faster regression of ulcers, petechia and anabroses in rats, which were induced by diclofenac taking. In the group of patients taking diclofenac together with quercetin, the ulcers and dyspeptic events were less found. The application of quercetin normalizes the function and metabolism of cartilage tissue of rabbits with an experimental osteoarthrosis and in patients with osteoartrosis. Quantum-chemical properties of molecule quercetin were studied using the methods of molecular mechanics MM+ and ab initio 6-31G*, and also semiempirical method. The following indices were investigated: distance between atoms (A), the distribution of electronic density of only external valency electrons, distribution of electrostatic potential; common energy of the exertion of molecule (kkal/mmol); binding energy (kkal/mmol); electron energy (kkal/mmol); energy of nucleus-nucleus interaction (kkal/mmol); formation heat (kkal/mmol); atomic charge (eB); value of the dipole moment of molecule (D); localization and energy of highest occupied orbital (HOMO) and the lowest unoccupied (LUMO) molecular orbital (eB) of quercetin miolecule; the value of absolute rigidity of chemical structure of bioflavonoid. It was shown, that bioflavonoid quercetin belongs to mild reagents, has nucleophilic properties, can react with alkaline, unsaturated and aromatic compounds,. Polar substitutes in the quercetine molecule influence on the distribution of superficial valency electrons and localization of HOMO and LUMO. The energy value of quercetin LUMO enables us to refer quercetine to the reducing agent and it is illustrated by antioxidant properties of this medicine. PMID:18663944

  1. Chemical kinetic studies on dry sorbents. Final report. [Sodium bicarbonate

    SciTech Connect

    Davis, W.T.; Keener, T.C.

    1982-02-15

    The scope of this research investigation has included a review of potential additives suitable for dry flue-gas desulfurization (FGD) and a bench scale laboratory study to determine the chemical kinetics for the reaction of five different sorbents with sulfur dioxide. The sorbents chosen included sodium bicarbonate (NaHCO/sub 3/), soda ash (Na/sub 2/CO/sub 3/), trona, lime (CaO) and hydrated lime (Ca(OH)/sub 2/). This study has shown that: (1) The reaction rate increases with temperature for soda ash and calcium oxide. The reaction temperature has an inverse effect on sodium bicarbonate and trona due, primarily, to the simultaneous thermal activation reaction. The calcium hydroxide-SO/sub 2/ reaction increased up to 550/sup 0/F, and then decreased, due to uneven gas flow distribution. (2) The reaction rates for soda ash, calcium oxide and calcium hydroxide were increased by decreasing their particle size. This effect was not confirmed for sodium bicarbonate and trona where reaction temperature was the most important reaction parameter. (3) Reaction with soda ash was found to be limited by the presence of an impervious ash layer which prevented interparticle gaseous diffusion. Calcium oxide and calcium hydroxide were found to be limited by a slow chemical reaction rate. Results on the rate-limiting steps for sodium bicarbonate and trona were inconclusive because of the simultaneous thermal activation reaction. (4) The effect of thermal activation was to increase the reaction rate for sodium bicarbonate and trona at lower temperatures. This effect was less pronounced at higher temperatures. (5) Results obtained for nitric oxide show limited adsorption for the five sorbents tested as compared to the finding for sulfur dioxide.

  2. Continuous nitrous oxide abatement in a novel denitrifying off-gas bioscrubber.

    PubMed

    Frutos, Osvaldo D; Arvelo, Ilan A; Pérez, Rebeca; Quijano, Guillermo; Muñoz, Raúl

    2015-04-01

    The potential of a bioscrubber composed of a packed bed absorption column coupled to a stirred tank denitrification bioreactor (STR) was assessed for 95 days for the continuous abatement of a diluted air emission of N2O at different liquid recycling velocities. N2O removal efficiencies of up to 40 ± 1 % were achieved at the highest recirculation velocity (8 m h(-1)) at an empty bed residence time of 3 min using a synthetic air emission containing N2O at 104 ± 12 ppmv. N2O was absorbed in the packed bed column and further reduced in the STR at efficiencies >80 % using methanol as electron donor. The long-term operation of the bioscrubber suggested that the specialized N2O degrading community established was not able to use N2O as nitrogen source. Additional nitrification assays showed that the activated sludge used as inoculum was not capable of aerobically oxidizing N2O to nitrate or nitrite, regardless of the inorganic carbon concentration tested. Denitrification assays confirmed the ability of non-acclimated activated sludge to readily denitrify N2O at a specific rate of 3.9 mg N2O g VSS h(-1) using methanol as electron donor. This study constitutes, to the best of our knowledge, the first systematic assessment of the continuous abatement of N2O in air emission. A characterization of the structure of the microbial population in the absorption column by DGGE-sequencing revealed a high microbial diversity and the presence of heterotrophic denitrifying methylotrophs. PMID:25547842

  3. Profiling the reproductive toxicity of chemicals from multigeneration studies in the toxicity reference database

    EPA Science Inventory

    Multigeneration reproduction studies are used to characterize parental and offspring systemic toxicity, as well as reproductive toxicity of pesticides, industrial chemicals and pharmaceuticals. Results from 329 multigeneration studies on 316 chemicals have been digitized into sta...

  4. ALTERNATIVE AND ENHANCED CHEMICAL CLEANING: CORROSION STUDIES RESULTS: FY2010

    SciTech Connect

    Wiersma, B.

    2010-09-29

    Due to the need to close High Level Waste storage tanks, chemical cleaning methods are needed for the removal of sludge heel materials remaining at the completion of mechanical tank cleaning efforts. Oxalic acid is considered the preferred cleaning reagent for heel dissolution of iron-based sludge. However, the large quantity of chemical reagents added to the tank farm from oxalic acid based cleaning has significant downstream impacts. Optimization of the oxalic acid cleaning process can potentially reduce the downstream impacts from chemical cleaning. To optimize oxalic acid usage, a detailed understanding of the chemistry of oxalic acid based sludge dissolution is required. Additionally, other acidic systems may be required for specific waste components that have low solubility in oxalic acid, and as a means to reduce oxalic acid usage in general. Electrochemical corrosion studies were conducted with 1 wt. % oxalic acid at mineral acid concentrations above and below the optimal conditions for this oxalic acid concentration. Testing environments included pure reagents, pure iron and aluminum phases, and sludge simulants. Mineral acid concentrations greater than 0.2 M and temperatures greater than 50 C result in unacceptably high corrosion rates. Results showed that manageable corrosion rates of carbon steel can be achieved at dilute mineral acid concentrations (i.e. less than 0.2 M) and low temperatures based on the contact times involved. Therefore, it is recommended that future dissolution and corrosion testing be performed with a dilute mineral acid and a less concentrated oxalic acid (e.g., 0.5 wt.%) that still promotes optimal dissolution. This recommendation requires the processing of greater water volumes than those for the baseline process during heel dissolution, but allows for minimization of oxalic acid additions. The following conclusions can be drawn from the test results: (1) In both nitric and sulfuric acid based reagents, the low temperature and

  5. Radiation and quantum chemical studies of chalcone derivatives.

    PubMed

    Gaikwad, P; Priyadarsini, K I; Naumov, S; Rao, B S M

    2010-08-01

    The reactions of oxidizing radicals ((*)OH, Br(2)(*-), and SO(4)(*-)) with -OH-, -CH(3)-, or -NH(2)-substituted indole chalcones and hydroxy benzenoid chalcones were studied by radiation and quantum chemical methods. The (*)OH radical was found to react by addition at diffusion-controlled rates (k = 1.1-1.7 x 10(10) dm(3) mol(-1) s(-1)), but Br(2)(*-) radical reacted by 2 orders of magnitude lower. Quantum chemical calculations at the B3LYP/6-31+G(d,p) level of theory have shown that the (C2-OH)(*), (C11-OH)(*), and (C10-OH)(*) adducts of the indole chalcones and the (C7-OH)(*) and (C8-OH)(*) adducts of the hydroxy benzenoid chalcones are more stable with DeltaH = -39 to -28 kcal mol(-1) and DeltaG = -32 to -19 kcal mol(-1). This suggests that (*)OH addition to the alpha,beta-unsaturated bond is a major reaction channel in both types of chalcones and is barrierless. The stability and lack of dehydration of the (*)OH adducts arise from two factors: strong frontier orbital interaction due to the low energy gap between interacting orbitals and the negligible Coulombic repulsion due to small absolute values of Mulliken charges. The transient absorption spectrum measured in the (*)OH radical reaction with all the indole chalcone derivatives exhibited a maximum at 390 nm, which is in excellent agreement with the computed value (394 nm). The formation of three phenolic products under steady-state radiolysis is in line with the three stable (*)OH adducts predicted by theory. Independent of the substituent, identical spectra (lambda(max) = 330-360 and approximately 580 nm) were obtained on one-electron oxidation of the three indole chalcones. MO calculations predict the deprotonation from the -NH group is more efficient than from the substituent due to the larger electron density on the N1 atom forming the chalcone indolyl radical. Its reduction potential was determined to be 0.56 V from the ABTS(*-)/ABTS(2-) couple. In benzenoid chalcones, the (*)OH adduct spectrum is

  6. Photocatalytic NO{sub x} abatement by calcium aluminate cements modified with TiO{sub 2}: Improved NO{sub 2} conversion

    SciTech Connect

    Pérez-Nicolás, M.; Navarro-Blasco, I.; Fernández, J.M.

    2015-04-15

    Photocatalytic activity of TiO{sub 2} was studied in two types of calcium aluminate cement (CAC) under two different curing regimes. The effect of the TiO{sub 2} addition on the setting time, consistency and mechanical properties of the CACs was evaluated. The abatement of gaseous pollutants (NO{sub x}) under UV irradiation was also assessed. These cementitious matrices were found to successfully retain NO{sub 2}: more abundant presence of aluminates in white cement (w-CAC, iron-lean) helped to better adsorb NO{sub 2}, thus improving the conversion performance of the catalyst resulting in a larger NO{sub x} removal under UV irradiation. As evidenced by XRD, SEM, EDAX and zeta potential analyses, the presence of ferrite in dark cement (d-CAC, iron-reach) induced a certain chemical interaction with TiO{sub 2}. The experimental findings suggest the formation of new iron titanate phases, namely pseudobrookite. The reduced band-gap energy of these compounds compared with that of TiO{sub 2} accounts for the photocatalytic activity of these samples.

  7. Toxicity of Abate? 4E (temephos) in mallard ducklings and the influence of cold

    USGS Publications Warehouse

    Fleming, W.J.; Heinz, G.H.; Franson, J.C.; Rattner, B.A.

    1985-01-01

    Diets mixed to contain 0,0.1, 1.0, 10 and 100 ppm temephos (determined chemically to contain less than 0.5, less than 0.5, 0.89, 6..0 and 59 ppm temephos, respectively) in an Abate ? 4E formulation, were fed to mallard (Anas platyrhynchos) ducklings for 7 d. During this period, half of the ducklings in each dietary treatment group were housed in a heated brooder (39 to 41?C) and half were housed in an unheated brooder (10 to 18?C). Mortality in all dietary groups in the unheated brooder was higher than in the heated brooder. High temephos-related mortality occurred in the 100 ppm group in the unheated brooder but not in any other diet-temperature groups. Ingestion of the 100 ppm temephos diet inhibited plasma cholinesterase (ChE) activity and elevated plasma corticosterone concentration and creatine phosphokinase activity, but other selected plasma chemistries were not affected in a dose-related manner. Brain ChE activity was depressed only in the 100 ppm dietary groups; maximum inhibition of brain ChE activity was 48%. These findings suggest that diets containing up to 10 ppm temephos do not directly affect duckling survival during the first week of life and that the toxicity of 100 ppm temephos is markedly enhanced by cold.

  8. Monitoring Fish Contaminant Responses to Abatement Actions: Factors that Affect Recovery

    SciTech Connect

    Southworth, George R; Peterson, Mark J; Roy, W Kelly; Mathews, Teresa J

    2011-01-01

    Monitoring of contaminant accumulation in fish has been conducted in East Fork Poplar Creek (EFPC) in Oak Ridge, Tennessee since 1985. Bioaccumulation trends are examined over a twenty year period coinciding with major pollution abatement actions by a Department of Energy facility at the stream s headwaters. Although EFPC is enriched in many contaminants relative to other local streams, only polychlorinated biphenyls (PCBs) and mercury (Hg) were found to accumulate in the edible portions of fish to levels of human health concern. Mercury concentrations in redbreast sunfish were found to vary with season of collection, sex and size of individual fish. Over the course of the monitoring, waterborne Hg concentrations were reduced[80%; however, this did not translate into a comparable decrease in Hg bioaccumulation at most sites. Mercury bioaccumulation in fish did respond to decreased inputs in the industrialized headwater reach, but paradoxically increased in the lowermost reach of EFPC. As a result, the downstream pattern of Hg concentration in fish changed from one resembling dilution of a headwater point source in the 1980s to a uniform distribution in the 2000s. The reason for this remains unknown, but is hypothesized to involve changes in the chemical form and reactivity of waterborne Hg associated with the removal of residual chlorine and the addition of suspended particulates to the streamflow. PCB concentrations in fish varied greatly from year-to-year, but always exhibited a pronounced downstream decrease, and appeared to respond to management practices that limited episodic inputs from legacy sources within the facility.

  9. Monitoring Fish Contaminant Responses to Abatement Actions: Factors that Affect Recovery

    NASA Astrophysics Data System (ADS)

    Southworth, George R.; Peterson, Mark J.; Roy, W. Kelly; Mathews, Teresa J.

    2011-06-01

    Monitoring of contaminant accumulation in fish has been conducted in East Fork Poplar Creek (EFPC) in Oak Ridge, Tennessee since 1985. Bioaccumulation trends are examined over a twenty year period coinciding with major pollution abatement actions by a Department of Energy facility at the stream's headwaters. Although EFPC is enriched in many contaminants relative to other local streams, only polychlorinated biphenyls (PCBs) and mercury (Hg) were found to accumulate in the edible portions of fish to levels of human health concern. Mercury concentrations in redbreast sunfish were found to vary with season of collection, sex and size of individual fish. Over the course of the monitoring, waterborne Hg concentrations were reduced >80%; however, this did not translate into a comparable decrease in Hg bioaccumulation at most sites. Mercury bioaccumulation in fish did respond to decreased inputs in the industrialized headwater reach, but paradoxically increased in the lowermost reach of EFPC. As a result, the downstream pattern of Hg concentration in fish changed from one resembling dilution of a headwater point source in the 1980s to a uniform distribution in the 2000s. The reason for this remains unknown, but is hypothesized to involve changes in the chemical form and reactivity of waterborne Hg associated with the removal of residual chlorine and the addition of suspended particulates to the streamflow. PCB concentrations in fish varied greatly from year-to-year, but always exhibited a pronounced downstream decrease, and appeared to respond to management practices that limited episodic inputs from legacy sources within the facility.

  10. Sustainability Indicators for Chemical Processes: III. Biodiesel Case Study

    EPA Science Inventory

    The chemical industry is one of the most important business sectors, not only economically, but also societally; as it allows humanity to attain higher standards and quality of life. Simultaneously, chemical products and processes can be the origin of potential human health and ...

  11. The Iron Blast Furnace: A Study in Chemical Thermodynamics.

    ERIC Educational Resources Information Center

    Treptow, Richard S.; Jean, Luckner

    1998-01-01

    Discusses the furnace from a chemical thermodynamics perspective. Examines the enthalpy, entropy, and free energy change for each reaction of importance. These properties are interpreted on the molecular level then used to deduce the conditions necessary for each reaction to occur in its intended direction. Chemical kinetics is also discussed.…

  12. LOSS OF ORGANIC CHEMICALS IN SOIL: PURE COMPOUND TREATABILITY STUDIES

    EPA Science Inventory

    Comprehensive screening data on the treatability of 32 organic chemicals in soil were developed. Of the evaluated chemicals, 22 were phenolic compounds. Aerobic batch laboratory microcosm experiments were conducted using two soils: an acidic clay soil with <1% organic matter and ...

  13. Studies of Trace Gas Chemical Cycles Using Observations, Inverse Methods and Global Chemical Transport Models

    NASA Technical Reports Server (NTRS)

    Prinn, Ronald G.

    2001-01-01

    For interpreting observational data, and in particular for use in inverse methods, accurate and realistic chemical transport models are essential. Toward this end we have, in recent years, helped develop and utilize a number of three-dimensional models including the Model for Atmospheric Transport and Chemistry (MATCH).

  14. Organic chemical degradation by remote study of the redox conditions

    NASA Astrophysics Data System (ADS)

    Fernandez, P. M.; Revil, A.; Binley, A. M.; Bloem, E.; French, H. K.

    2014-12-01

    Monitoring the natural (and enhanced) degradation of organic contaminants is essential for managing groundwater quality in many parts of the world. Contaminated sites often have limited access, hence non-intrusive methods for studying redox processes, which drive the degradation of organic compounds, are required. One example is the degradation of de-icing chemicals (glycols and organic salts) released to the soil near airport runways during winter. This issue has been broadly studied at Oslo airport, Gardermoen, Norway using intrusive and non-intrusive methods. Here, we report on laboratory experiments that aim to study the potential of using a self-potential, DCresistivity, and time-domain induced polarization for geochemical characterization of the degradation of Propylene Glycol (PG). PG is completely miscible in water, does not adsorb to soil particles and does not contribute to the electrical conductivity of the soil water. When the contaminant is in the unsaturated zone near the water table, the oxygen is quickly consumed and the gas exchange with the surface is insufficient to ensure aerobic degradation, which is faster than anaerobic degradation. Since biodegradation of PG is highly oxygen demanding, anaerobic pockets can exist causing iron and manganese reduction. It is hypothesised that nitrate would boost the degradation rate under such conditions. In our experiment, we study PG degradation in a sand tank. We provide the system with an electron highway to bridge zones with different redox potential. This geo-battery system is characterized by self-potential, resistivity and induced polarization anomalies. An example of preliminary results with self-potential at two different times of the experiment can be seen in the illustration. These will be supplemented with more direct information on the redox chemistry: in-situ water sampling, pH, redox potential and electrical conductivity measurements. In parallel, a series of batch experiments have been

  15. NO{sub x} Abatement Pilot Plant 90-day test results report

    SciTech Connect

    McCray, J.A.; Boardman, R.D.

    1991-08-30

    High-level radioactive liquid wastes produced during nuclear fuel reprocessing at the Idaho Chemical Processing Plant are calcined in the New Waste Calcining Facility (NWCF) to provide both volume reduction and a more stable waste form. Because a large component of the HLW is nitric acid, high levels of oxides of nitrogen (NO{sub x}) are produced in the process and discharged to the environment via the calciner off-gas. The NO{sub x} abatement program is required by the new Fuel Processing Restoration (FPR) project permit to construct to reduce NO{sub x} emissions from the NWCF. Extensive research and development has indicated that the selective catalytic reduction (SCR) process is the most promising technology for treating the NWCF off-gas. Pilot plant tests were performed to determine the compatibility of the SCR process with actual NWCF off-gas. Test results indicate that the SCR process is a viable method for abating the NO{sub x} from the NWCF off-gas. Reduction efficiencies over 95% can be obtained, with minimal amounts of ammonia slip, provided favorable operating conditions exist. Two reactors operated with series flow will provide optimum reduction capabilities. Typical operation should be performed with a first reactor stage gas space velocity of 20,000 hr{sup {minus}1} and an inlet temperature of 320{degrees}C. The first stage exhaust NO{sub x} concentration will then dictate the parameter settings for the second stage. Operation should always strive for a peak reactor temperature of 520{degrees}C in both reactors, with minimal NH{sub 3} slip from the second reactor. Frequent fluctuations in the NWCF off-gas NO{sub x} concentration will require a full-scale reduction facility that is versatile and quick-responding. Sudden changes in NWCF off-gas NO{sub x} concentrations will require quick detection and immediate response to avoid reactor bed over-heating and/or excessive ammonia slip.

  16. Combustion Research Program: Flame studies, laser diagnostics, and chemical kinetics

    SciTech Connect

    Crosley, D.R.

    1992-09-01

    This project has comprised laser flame diagnostic experiments, chemical kinetics measurements, and low pressure flame studies. Collisional quenching has been investigated for several systems: the OH radical, by H{sub 2}0 in low pressure flames; the rotational level dependence for NH, including measurements to J=24; and of NH{sub 2} at room temperature. Transition probability measurements for bands involving v{prime} = 2 and 3 of the A-X system of OH were measured in a flame. Laser-induced fluorescence of vinyl radicals was unsuccessfully attempted. RRKM and transition state theory calculations were performed on the OH + C{sub 2}H{sub 4} reaction, on the t-butyl radical + HX; and transition state theory has been applied to a series of bond scission reactions. OH concentrations were measured quantitatively in low pressure H{sub 2}/N{sub 2}O and H{sub 2}/O{sub 2} flames, and the ability to determine spatially precise flame temperatures accurately using OH laser-induced fluorescence was studied.

  17. Fundamental studies of the chemical vapor deposition of diamond

    SciTech Connect

    Stevenson, D.A.

    1991-01-01

    The plasma or thermally enhanced low pressure chemical vapor deposition of diamond films is an exciting development with many challenging fundamental problems. The early stages of nucleation is relevant to the initial growth rate and the perfection and morphology of the deposit. To isolate one of the factors that influence nucleation, we have studied the effect of surface topography on the nucleation process. Our earlier work has shown preferential nucleation on sharp convex features and we have proposed several possible reasons for this behavior, including dangling bonds at the convex features. In our recent work, we have extended our investigation to include a novel patterning of silicon substrates used to pattern silicon solar cells. The results are consistent with our earlier observations that the majority of nucleation events occur on protruding surface features. In an effort to establish whether dangling bonds at the protruding surfaces may be responsible for the selective nucleation, we have evaluated the dangling bond concentration using electron spin resonance. We have carried out deposition under nominally identical surface topography, but with different concentrations of dangling bonds at or near the surface. The results of this study indicate that dangling bonds play a minor role in enhancing nucleation, in contrast to a substantial role played by special surface topographical features. In the course of the past year, we have submitted four manuscripts for publication and have made six presentations.

  18. QUANTITATIVE EVALUATION OF AIR FILTRATION SYSTEMS IN USE AT ASBESTOS ABATEMENT SITES: RESEARCH IN PROGRESS

    EPA Science Inventory

    High Efficiency Particulate Air (HEPA) filtration systems serve as the principal engineering control to remove asbestos particulate from airstreams at abatement projects. owever, little quantitative information is available on the integrity of these air filtration systems in prev...

  19. Alternative Enhanced Chemical Cleaning Basic Studies Results FY09

    SciTech Connect

    Hay, M.; King, W.

    2010-05-05

    Due to the need to close waste storage tanks, chemical cleaning methods are needed for the effective removal of the heels. Oxalic acid is the preferred cleaning reagent for sludge heel dissolution, particularly for iron-based sludge, due to the strong complexing strength of the oxalate. However, the large quantity of oxalate added to the tank farm from oxalic acid based chemical cleaning has significant downstream impacts. Optimization of the oxalic acid cleaning process can potentially reduce the downstream impacts from chemical cleaning. To optimize oxalic acid usage, a detailed understanding of the chemistry of oxalic acid based sludge dissolution is required. Additionally, other acid systems may be required for specific waste components with low solubility in oxalic acid and as a means to reduce oxalic acid usage in general. Solubility tests were conducted using non-radioactive, pure metal phases known to be the primary phases present in High Level Waste sludge. The metal phases studied included the aluminum phases gibbsite and boehmite and the iron phases magnetite and hematite. Hematite and boehmite are expected to be the most difficult iron and aluminum phases to dissolve. These mineral phases have been identified in both SRS and Hanford High Level Waste sludge. Acids evaluated for dissolution included oxalic, nitric, and sulfuric acids. The results of the solubility tests indicate that oxalic and sulfuric acids are more effective for the dissolution of the primary sludge phases. For boehmite, elevated temperature will be required to promote effective phase dissolution in the acids studied. Literature reviews, thermodynamic modeling, and experimental results have all confirmed that pH control using a supplemental proton source (additional acid) is critical for minimization of oxalic acid usage during the dissolution of hematite. These results emphasize the importance of pH control in optimizing hematite dissolution in oxalic acid and may explain the somewhat

  20. Long-run energy-technology choices, CO/sub 2/ abatement policies, and CO/sub 2/ shadow prices

    SciTech Connect

    Kosobud, R.F.; Daly, T.A.; Chang, Y.I.

    1983-01-01

    This study advances a particular research methodology in which existing knowledge of CO/sub 2/ environmental quality and damage functions is embedded in a long-run growth model that permits substitution among energy technologies. The authors illustrate a decentralized abatement policy in which the shadow price of constraining CO/sub 2/ concentrations is utilized to estimate an optimal tax rate on CO/sub 2/ polluting technologies. A quantitative implementation of this approach is carried out based on existing energy-resource reserve and technology cost data, and on their appraisal of preliminary environmental quality and damage data.

  1. Chemical and biological warfare: General studies. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1995-09-01

    The bibliography contains citations concerning federally sponsored and conducted studies into chemical and biological warfare operations and planning. These studies cover areas not addressed in other parts of this series. The topics include production and storage of agents, delivery techniques, training, military and civil defense, general planning studies, psychological reactions to chemical warfare, evaluations of materials exposed to chemical agents, and studies on banning or limiting chemical warfare. Other published searches in this series on chemical warfare cover detection and warning, defoliants, protection, and biological studies, including chemistry and toxicology.(Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  2. Chemical and biological warfare: General studies. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1997-11-01

    The bibliography contains citations concerning federally sponsored and conducted studies into chemical and biological warfare operations and planning. These studies cover areas not addressed in other parts of this series. The topics include production and storage of agents, delivery techniques, training, military and civil defense, general planning studies, psychological reactions to chemical warfare, evaluations of materials exposed to chemical agents, and studies on banning or limiting chemical warfare. Other published searches in this series on chemical warfare cover detection and warning, defoliants, protection, and biological studies, including chemistry and toxicology.(Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  3. Chemical and biological warfare: General studies. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1996-10-01

    The bibliography contains citations concerning federally sponsored and conducted studies into chemical and biological warfare operations and planning. These studies cover areas not addressed in other parts of this series. The topics include production and storage of agents, delivery techniques, training, military and civil defense, general planning studies, psychological reactions to chemical warfare, evaluations of materials exposed to chemical agents, and studies on banning or limiting chemical warfare. Other published searches in this series on chemical warfare cover detection and warning, defoliants, protection, and biological studies, including chemistry and toxicology. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  4. Chemical and biological warfare: General studies. (Latest citations from the NTIS bibliographic database). NewSearch

    SciTech Connect

    Not Available

    1994-10-01

    The bibliography contains citations concerning federally sponsored and conducted studies into chemical and biological warfare operations and planning. These studies cover areas not addressed in other parts of this series. The topics include production and storage of agents, delivery techniques, training, military and civil defense, general planning studies, psychological reactions to chemical warfare, evaluations of materials exposed to chemical agents, and studies on banning or limiting chemical warfare. Other published searches in this series on chemical warfare cover detection and warning, defoliants, protection, and biological studies, including chemistry and toxicology. (Contains 250 citations and includes a subject term index and title list.)

  5. Chemical and biological warfare: General studies. (Latest citations from the NTIS Bibliographic database). Published Search

    SciTech Connect

    Not Available

    1993-11-01

    The bibliography contains citations concerning federally sponsored and conducted studies into chemical and biological warfare operations and planning. These studies cover areas not addressed in other parts of this series. The topics include production and storage of agents, delivery techniques, training, military and civil defense, general planning studies, psychological reactions to chemical warfare, evaluations of materials exposed to chemical agents, and studies on banning or limiting chemical warfare. Other published searches in this series on chemical warfare cover detection and warning, defoliants, protection, and biological studies, including chemistry and toxicology. (Contains 250 citations and includes a subject term index and title list.)

  6. An experimental study of the chemical oxygen-iodine laser

    NASA Astrophysics Data System (ADS)

    Vagin, N. P.; Karapetian, D. G.; Konoshenko, A. F.; Kriukov, P. G.; Paziuk, V. S.

    The construction of an oxygen-iodine laser with an output power of up to 400 W based on a chemical singlet oxygen generator is reported. The possibility of achieving high outputs using modular design is demonstrated. The possibility of the operation of chemical oxygen-iodine lasers in the pulsed mode is analyzed, and it is shown that, in this mode, such lasers can operate without a low-temperature trap. In addition, the pulsed mode makes it possible to control the lasing pulse length over a wide range. Possible applications of pulsed chemical oxygen-iodine lasers in thermonuclear fusion are briefly discussed.

  7. Scope for active noise abatement in vehicle diesel engines

    NASA Astrophysics Data System (ADS)

    Summerauer, I.; Boesch, N.

    1984-04-01

    Noise reduction measures must be directed to the engine, the exhaust system, and the cooling system (fan) all of which contribute approximately 90% of the sound energy emitted from commercial diesel trucks. The noise generation processes were visualized and limiting conditions fixed by law were considered in establishing criteria for active solar noise abatement measures. A more effective silencer and better vibration damping on the surface of the silencer and exhaust pipes can reduce noise from the exhaust system. Acoustic emission generated by the fan and air flow can be reduced by decreasing flow velocity or by turning on the fan only when a full cooling output is required (10% of the time). Active measures are needed on the engine itself either at the point of the solid-borne sound transmission or at the point of the solid-borne vibrations. The predominant effect is on the engine casing; oil sump; air suction pipe or air charge line; the flywheel casing; and the clutch housing.

  8. Optimized combinations of abatement strategies for urban mobile sources.

    PubMed

    Yu, T Y; Lin, Y C; Chang, L F

    2000-08-01

    The maximum incremental reactivity (MIR) scale was chosen as a practical index for quantifying ozone-forming impacts. The integer linear and nonlinear programming techniques were employed as the optimization method to maximize MIR and volatile organic compound (VOC) reductions, and minimize ozone's marginal cost with varied control costs. Mobile vehicles were divided into nine categories according to the demands of decision makers and the distinctive features of local circumstance in metro-Taipei. The emission factor (EF) and vehicle kilometers traveled (VKT) of each kind of vehicle were estimated by MOBILE5B model via native parameters and questionnaires. Compressed natural gas (CNG) and inspection and maintenance (I/M) were the alternative control programs for buses and touring buses; liquefied petroleum gas (LPG), I/M, methanol, electrical vehicle (EV) were for taxis and low duty gasoline vehicles. EV, methanol, and I/M were the possible control methods for two-stroke and four-stroke engine motorcycles; I/M programs for low-duty diesel trucks, heavy-duty diesel trucks, and low-duty gasoline trucks. The results include the emission ratios of specific vehicle to all vehicles, the best combination of abated measures based on different objectives, and the marginal cost for ozone and VOC with varied control costs. PMID:11057602

  9. Abatement of gaseous and particulate contamination in a space instrument

    NASA Technical Reports Server (NTRS)

    Scialdone, J. J.

    1983-01-01

    Methods to prevent the ingestion of external contaminants into the instrument and to limit the effect of the self-generated contaminants during ground, launch, orbiting and landing phases of flight were investigated. It is proposed that a positive pressure and purging flow of clean gas inside the instrument be maintained while on the ground, during launch, and for a period of time in orbit. The pressure to be maintained and the required purging flow are examined in terms of the effectiveness in preventing gaseous and particulate contaminants ingestion and the abatement of the self-generated contaminants. Considerations have been given to the venting requirements for the structural integrity of the instrument during launch, the limitations on the volume and the pressure of the purging gas to be carried along in orbit, and the required venting area is established based on the internal volume of the instrument, the allowable pressure differential, and the rate of external pressure change during launch. Previously announced in STAR as N83-23350

  10. Identification of root cause and abatement of vibration of monochromator.

    SciTech Connect

    Jendrzejczyk, J. A.

    1998-01-13

    Silicon crystal mirrors are used to reflect high-intensity X-ray beams. A large amount of heat is generated in each mirror. To minimize the effect of thermal expansion on the crystal mirrors, heat is removed by pumping liquid gallium (with a boiling point of 29.8 C) through passages in the crystal mirrors. During system operation, mirror motion should be kept to an acceptable level to avoid performance degradation. There are many potential sources of excitation to the crystal assembly; one such source is the flowing gallium. Two series of tests were performed earlier for a near-prototypical gallium cooling system (1-2). This paper describes a series of tests to measure the general vibration response characteristics of critical components in the monochromator system that contains the mirrors. The main objective of this work is to identify the root cause of vibration and to recommend general guidelines for abatement of vibration. This is achieved by performing many tests to understand the response characteristics under various conditions, by analysis of the response data, and by use of some theoretical considerations.

  11. Abatement of an aircraft exhaust plume using aerodynamic baffles.

    PubMed

    Bennett, Michael; Christie, Simon M; Graham, Angus; Garry, Kevin P; Velikov, Stefan; Poll, D Ian; Smith, Malcolm G; Mead, M Iqbal; Popoola, Olalekan A M; Stewart, Gregor B; Jones, Roderic L

    2013-03-01

    The exhaust jet from a departing commercial aircraft will eventually rise buoyantly away from the ground; given the high thrust/power (i.e., momentum/buoyancy) ratio of modern aero-engines, however, this is a slow process, perhaps requiring ∼ 1 min or more. Supported by theoretical and wind tunnel modeling, we have experimented with an array of aerodynamic baffles on the surface behind a set of turbofan engines of 124 kN thrust. Lidar and point sampler measurements show that, as long as the intervention takes place within the zone where the Coanda effect holds the jet to the surface (i.e., within about 70 m in this case), then quite modest surface-mounted baffles can rapidly lift the jet away from the ground. This is of potential benefit in abating both surface concentrations and jet blast downstream. There is also some modest acoustic benefit. By distributing the aerodynamic lift and drag across an array of baffles, each need only be a fraction of the height of a single blast fence. PMID:23343109

  12. Abatement of malodorants from pesticide factory in dielectric barrier discharges.

    PubMed

    Chen, Jie; Yang, Jiantao; Pan, Hua; Su, Qingfa; Liu, Yamin; Shi, Yao

    2010-05-15

    Traditional odor control methods are limitative technically and economically for the abatement of odor from pesticide factory due to its toxicity and complicated composition. Non-thermal plasma (NTP) methods, typically characterized by high removal efficiency, energy yields and good economy, offer possible alternative solutions. This paper provides laboratory scale experimental data on the removal of simulated odors from pesticide factory with various humidity (0-0.8 vol%) and oxygen contents (0-21%) by a dielectric barrier discharge (DBD) reactor. Peak voltage and initial dimethylamine (DML) concentration are important factors that influence the DML removal efficiency and energy yield. The conversion of DML of 761 mg/m(3) reaches 100% at a peak voltage of 41.25 kV. Under the experiment conditions, the conversion of DML increases with an increase of oxygen contents. And the highest DML conversion was achieved with the gas stream containing 0.3% water. Simultaneously, the concentration of O(3) and OH radical in reactor was measured. Higher conversion, higher energy yield and fewer byproducts were found in mixed odor (DML+dimethyl sulfide (DMS)) treatment than that in single odor treatment. The energy yield is promoted from 2.13 to 5.20mg/kJ. PMID:20116170

  13. New semisynthetic vinca alkaloids: chemical, biochemical and cellular studies

    PubMed Central

    Orosz, F; Comin, B; Raïs, B; Puigjaner, J; Kovács, J; Tárkányi, G; Ács, T; Keve, T; Cascante, M; Ovádi, J

    1999-01-01

    A new semisynthetic anti-tumour bis-indol compound, KAR-2 [3′-(β-chloroethyl)-2′,4′-dioxo-3,5′-spiro-oxazolidino-4-deacetoxy-vinblastine] with lower toxicity than vinca alkaloids used in chemotherapy binds to calmodulin but, in contrast to vinblastine, does not exhibit anti-calmodulin activity. To investigate whether the modest chemical modification of bis-indol structure is responsible for the lack of anti-calmodulin potency and for the different pharmacological effects, new derivatives have been synthesized for comparative studies. The synthesis of the KAR derivatives are presented. The comparative studies showed that the spiro-oxazolidino ring and the substitution of a formyl group to a methyl one were responsible for the lack of anti-calmodulin activities. The new derivatives, similar to the mother compounds, inhibited the tubulin assembly in polymerization tests in vitro, however their inhibitory effect was highly dependent on the organization state of microtubules; bundled microtubules appeared to be resistant against the drugs. The maximal cytotoxic activities of KAR derivatives in in vivo mice hosting leukaemia P388 or Ehrlich ascites tumour cells appeared similar to that of vinblastine or vincristine, however significant prolongation of life span could be reached with KAR derivatives only after the administration of a single dose. These studies plus data obtained using a cultured human neuroblastoma cell line showed that KAR compounds displayed their cytotoxic activities at significantly higher concentrations than the mother compounds, although their antimicrotubular activities were similar in vitro. These data suggest that vinblastine/vincristine damage additional crucial cell functions, one of which could be related to calmodulin-mediated processes. © 1999 Cancer Research Campaign PMID:10188876

  14. Low-cost household paint abatement to reduce children's blood lead levels

    SciTech Connect

    Taha, T.; Kanarek, M.S.; Schultz, B.D.; Murphy, A.

    1999-11-01

    The purpose was to examine the effectiveness of low-cost abatement on children's blood lead levels. Blood lead was analyzed before and after abatement in 37 homes of children under 7 years old with initial blood lead levels of 25--44 {micro}g/dL. Ninety-five percent of homes were built before 1950. Abatement methods used were wet-scraping and repainting deteriorated surfaces and wrapping window wells with aluminum or vinyl. A control group was retrospectively selected. Control children were under 7 years old, had initial blood lead levels of 25--44 {micro}g/dL and a follow-up level at least 28 days afterward, and did not have abatements performed in their homes between blood lead levels. After abatement, statistically significant declines occurred in the intervention children's blood lead levels. The mean decline was 22%, 1 to 6 months after treatment. After adjustment for seasonality and child's age, the mean decline was 6.0 {micro}g/dL, or 18%. The control children's blood levels did not decline significantly. There was a mean decline of 0.25 {micro}g/dL, or 0.39%. After adjustment for seasonality and age, the mean decline for control children was 1.6 {micro}g/dL, or 1.8%. Low-cost abatement and education are effective short-term interim controls.

  15. Rodent-repellent studies. III. Advanced studies in the evaluation of chemical repellents

    USGS Publications Warehouse

    Bellack, E.; DeWitt, J.B.

    1949-01-01

    In order to bridge the gap between preliminary screening of chemicals for potential rodent repellency and the application ofthese compounds to paper cartons, more advanced studies in the evaluation ofpromising materials have been carried out. These studies have resulted in: (1) a modification of the food acceptance technique which eliminates doubtful compounds and also provides a closer analogy to the ultimate goal, and (2) a method for rapidly testing chemicals incorporated in paper. When the results of these latter tests are expressed as a function of time, it can be shown that a distinct correlation exists between the deterrency exhibited by treated paper and the repellency of treated food.

  16. Quantitative study on the chemical solution deposition of zinc oxysulfide

    SciTech Connect

    Reinisch, Michael; Perkins, Craig L.; Steirer, K. Xerxes

    2015-11-21

    Zinc Oxysulfide (ZnOS) has demonstrated potential in the last decade to replace CdS as a buffer layer material since it is a wide-band-gap semiconductor with performance advantages over CdS (Eg = 2.4 eV) in the near UV-range for solar energy conversion. However, questions remain on the growth mechanisms of chemical bath deposited ZnOS. In this study, a detailed model is employed to calculate solubility diagrams that describe simple conditions for complex speciation control using only ammonium hydroxide without additional base. For these conditions, ZnOS is deposited via aqueous solution deposition on a quartz crystal microbalance in a continuous flow cell. Data is used to analyze the growth rate dependence on temperature and also to elucidate the effects of dimethylsulfoxide (DMSO) when used as a co-solvent. Activation energies (EA) of ZnOS are calculated for different flow rates and solution compositions. As a result, the measured EA relationships are affected by changes in the primary growth mechanism when DMSO is included.

  17. Quantitative study on the chemical solution deposition of zinc oxysulfide

    DOE PAGESBeta

    Reinisch, Michael; Perkins, Craig L.; Steirer, K. Xerxes

    2015-11-21

    Zinc Oxysulfide (ZnOS) has demonstrated potential in the last decade to replace CdS as a buffer layer material since it is a wide-band-gap semiconductor with performance advantages over CdS (Eg = 2.4 eV) in the near UV-range for solar energy conversion. However, questions remain on the growth mechanisms of chemical bath deposited ZnOS. In this study, a detailed model is employed to calculate solubility diagrams that describe simple conditions for complex speciation control using only ammonium hydroxide without additional base. For these conditions, ZnOS is deposited via aqueous solution deposition on a quartz crystal microbalance in a continuous flow cell.more » Data is used to analyze the growth rate dependence on temperature and also to elucidate the effects of dimethylsulfoxide (DMSO) when used as a co-solvent. Activation energies (EA) of ZnOS are calculated for different flow rates and solution compositions. As a result, the measured EA relationships are affected by changes in the primary growth mechanism when DMSO is included.« less

  18. Quantum-chemical study of CHCl3-SO2 association.

    PubMed

    Hippler, Michael

    2005-11-22

    CHCl(3)-SO(2) association is studied by high-level quantum-chemical calculations of stationary points of the dimer electronic potential-energy hypersurface, including correlated second-order Moller-Plesset and CCSD(T) calculations with basis sets up to 6-311++G(d,p). During geometry optimization, frequency, and energy calculations, a self-written computer code embedding the GAMESS ab initio program suite applies counterpoise correction of the basis set superposition error. A CH...O hydrogen-bonded complex (DeltaE(0)=-8.73 kJmol) with a 2.4 A intermolecular H...O distance and two very weak van der Waals complexes (DeltaE(0)=-3.78 and -2.94 kJmol) are located on the counterpoise-corrected potential-energy surface. The intermolecular interactions are characterized by Kitaura-Morokuma interaction energy decompositions and Mulliken electron population analyses. The unusual hydrogen bond is distinguished by a CH-bond contraction, a pronounced enhancement of the IR intensity and a shift to higher frequency ("blueshift") of the CH-stretching vibration compared to the CHCl(3) monomer. Spectroscopy and association in liquid solution is also discussed; our results provide an alternative explanation for features in the CH-stretching vibration spectrum of chloroform dissolved in liquid sulfur dioxide which have been attributed previously to an intermolecular Fermi resonance. PMID:16351260

  19. Quantum-chemical study of CHCl3-SO2 association

    NASA Astrophysics Data System (ADS)

    Hippler, Michael

    2005-11-01

    CHCl3-SO2 association is studied by high-level quantum-chemical calculations of stationary points of the dimer electronic potential-energy hypersurface, including correlated second-order Møller-Plesset and CCSD(T) calculations with basis sets up to 6-311++G(d,p). During geometry optimization, frequency, and energy calculations, a self-written computer code embedding the GAMESS ab initio program suite applies counterpoise correction of the basis set superposition error. A CH ⋯O hydrogen-bonded complex (ΔE0=-8.73kJ/mol) with a 2.4Å intermolecular H ⋯O distance and two very weak van der Waals complexes (ΔE0=-3.78 and -2.94kJ /mol) are located on the counterpoise-corrected potential-energy surface. The intermolecular interactions are characterized by Kitaura-Morokuma interaction energy decompositions and Mulliken electron population analyses. The unusual hydrogen bond is distinguished by a CH-bond contraction, a pronounced enhancement of the IR intensity and a shift to higher frequency ("blueshift") of the CH-stretching vibration compared to the CHCl3 monomer. Spectroscopy and association in liquid solution is also discussed; our results provide an alternative explanation for features in the CH-stretching vibration spectrum of chloroform dissolved in liquid sulfur dioxide which have been attributed previously to an intermolecular Fermi resonance.

  20. Studies on residue-free decontaminants for chemical warfare agents.

    PubMed

    Wagner, George W

    2015-03-17

    Residue-free decontaminants based on hydrogen peroxide, which decomposes to water and oxygen in the environment, are examined as decontaminants for chemical warfare agents (CWA). For the apparent special case of CWA on concrete, H2O2 alone, without any additives, effectively decontaminates S-2-(diisopropylamino)ethyl O-ethyl methylphosphonothioate (VX), pinacolyl methylphosphorofluoridate (GD), and bis(2-choroethyl) sulfide (HD) in a process thought to involve H2O2 activation by surface-bound carbonates/bicarbonates (known H2O2 activators for CWA decontamination). A plethora of products are formed during the H2O2 decontamination of HD on concrete, and these are characterized by comparison to synthesized authentic compounds. As a potential residue-free decontaminant for surfaces other than concrete (or those lacking adsorbed carbonate/bicarbonate) H2O2 activation for CWA decontamination is feasible using residue-free NH3 and CO2 as demonstrated by reaction studies for VX, GD, and HD in homogeneous solution. Although H2O2/NH3/CO2 ("HPAC") decontaminants are active for CWA decontamination in solution, they require testing on actual surfaces of interest to assess their true efficacy for surface decontamination. PMID:25710477

  1. Periodic quantum chemical studies on anhydrous and hydrated acid clinoptilolite.

    PubMed

    Valdiviés Cruz, Karell; Lam, Anabel; Zicovich-Wilson, Claudio M

    2014-08-01

    Periodic quantum chemistry methods as implemented in the crystal09 code were considered to study acid clinoptilolite (HEU framework type), both anhydrous and hydrated. The most probable location of acid sites and water molecules together with other structural details has been the object of particular attention. Calculations were performed at hybrid and pristine DFT levels of theory with a VDZP quality basis set in order to compare performances. It arises that PBE0 provides the best agreement with experimental data as concerns structural features and the most stable Al distribution in the framework. The role of the water molecule distribution in the stability of the systems, the most probable structure that they induce in the material, and their eventual influence on further chemical modification processes, such as dealumination, are discussed in detail. Results show that, apart from the usually considered interactions of water molecules with the zeolite framework, that is, a H-bond with Brönsted acid sites and coordination with framework Al as Lewis ones, it is necessary to consider cooperation of other weaker effects so as to fully understand the hydration effect in this kind of materials. PMID:24730675

  2. Chemical mixing study for the Hanford TWRS Supporting facilities (U)

    SciTech Connect

    Heal, D.W.; Brantley, W.M.

    1996-09-03

    This Engineering Calculation addresses consequences of mixing any two hazardous chemicals contained in the same section of TWRS supporting facilities, as screened in accordance with `Westinghouse Savannah River Company Engineering and Construction Services Division Guidelines and Methods.`

  3. The Lewis Chemical Equilibrium Program with parametric study capability

    NASA Technical Reports Server (NTRS)

    Sevigny, R.

    1981-01-01

    The program was developed to determine chemical equilibrium in complex systems. Using a free energy minimization technique, the program permits calculations such as: chemical equilibrium for assigned thermodynamic states; theoretical rocket performance for both equilibrium and frozen compositions during expansion; incident and reflected shock properties; and Chapman-Jouget detonation properties. It is shown that the same program can handle solid coal in an entrained flow coal gasification problem.

  4. Spectroscopic and photochemical study of molecules important in chemical evolution

    NASA Technical Reports Server (NTRS)

    Becker, R. S.

    1973-01-01

    The primary broad goals of this research are to investigate (1) the possible reactions responsible for generation of compounds important in chemical evolution, and (2) reactions of compounds important in chemical evolution. In both cases the interest includes molecules that exist in interstellar space as well as those present on or near other planets and those which were thought to be present on or near the primitive earth.

  5. A study on chemical composition and detection of chemical adulteration in tetra pack milk samples commercially available in Multan.

    PubMed

    Awan, Adeela; Naseer, Misbah; Iqbal, Aasfa; Ali, Muhammad; Iqbal, Rehana; Iqbal, Furhan

    2014-01-01

    The aim of this study was to analyze and compare the chemical composition of 8 tetra pack milk samples, Olpers (S1), Haleeb (S2), Good milk (S3), Everyday (S4), Milk Pack (S5), Dairy Queen (S6), Dairy Umang (S7), Nurpur (S8) available in local markets and to detect the presence of various chemical adulterants in tetra pack milk samples in Southern Punjab (Pakistan). Density, pH, solid not fat, total solids, lactometer reading, specific gravity and fat contents were analyzed to determine the chemical composition of milk samples. Our results revealed that all the studied parameters had statistically non significant differences (P>0.05) except total fat in milk samples which was significantly different (P=0.03) among the 8 studied milk samples. Presence of a number of chemical adulterants, formalin, cane sugar, starch, glucose, ammonium sulphate, salt, pulverized soap, detergents, skim milk powder, benzoic acid, salicylic acid, borax, boric acid and alkalinity were also detected in milk samples following standard procedures. Results indicated that formalin, cane sugar, glucose, alkalinity and benzoic acid were present in all samples while salt test was positive only for Olper milk. All other studied adulterants were not detected in 8 milk samples under study. % fat was the only significantly different feature among the studied milk quality parameters with S8 containing lowest while S5 having the maximum % fat. PMID:24374447

  6. Transport Sector Marginal Abatement Cost Curves in Computable General Equilibrium Model

    NASA Astrophysics Data System (ADS)

    Tippichai, Atit; Fukuda, Atsushi; Morisugi, Hisayoshi

    In the last decade, computable general equilibrium (CGE) models have emerged a standard tool for climate policy evaluation due to their abilities to prospectively elucidate the character and magnitude of the economic impacts of energy and environmental policies. Furthermore, marginal abatement cost (MAC) curves which represent GHG emissions reduction potentials and costs can be derived from these top-down economic models. However, most studies have never address MAC curves for a specific sector that have a large coverage of countries which are needed for allocation of optimal emission reductions. This paper aims to explicitly describe the meaning and character of MAC curves for transport sector in a CGE context through using the AIM/CGE Model developed by Toshihiko Masui. It found that the MAC curves derived in this study are the inverse of the general equilibrium reduction function for CO2 emissions. Moreover, the transport sector MAC curves for six regions including USA, EU-15, Japan, China, India, and Brazil, derived from this study are compared to the reduction potentials under 100 USD/tCO2 in 2020 from a bottom-up study. The results showed that the ranking of the regional reduction potentials in transport sector from this study are almost same with the bottom-up study except the ranks of the EU-15 and China. In addition, the range of the reduction potentials from this study is wider and only the USA has higher potentials than those derived from the bottom-up study.

  7. Crossed molecular beam studies of atmospheric chemical reaction dynamics

    SciTech Connect

    Zhang, Jingsong

    1993-04-01

    The dynamics of several elementary chemical reactions that are important in atmospheric chemistry are investigated. The reactive scattering of ground state chlorine or bromine atoms with ozone molecules and ground state chlorine atoms with nitrogen dioxide molecules is studied using a crossed molecular beams apparatus with a rotatable mass spectrometer detector. The Cl + O{sub 3} {yields} ClO + O{sub 2} reaction has been studied at four collision energies ranging from 6 kcal/mole to 32 kcal/mole. The derived product center-of-mass angular and translational energy distributions show that the reaction has a direct reaction mechanism and that there is a strong repulsion on the exit channel. The ClO product is sideways and forward scattered with respect to the Cl atom, and the translational energy release is large. The Cl atom is most likely to attack the terminal oxygen atom of the ozone molecule. The Br + O{sub 3} {yields} ClO + O{sub 2} reaction has been studied at five collision energies ranging from 5 kcal/mole to 26 kcal/mole. The derived product center-of-mass angular and translational energy distributions are quite similar to those in the Cl + O{sub 3} reaction. The Br + O{sub 3} reaction has a direct reaction mechanism similar to that of the Cl + O{sub 3} reaction. The electronic structure of the ozone molecule seems to play the central role in determining the reaction mechanism in atomic radical reactions with the ozone molecule. The Cl + NO{sub 2} {yields} ClO + NO reaction has been studied at three collision energies ranging from 10.6 kcal/mole to 22.4 kcal/mole. The center-of-mass angular distribution has some forward-backward symmetry, and the product translational energy release is quite large. The reaction proceeds through a short-lived complex whose lifetime is less than one rotational period. The experimental results seem to show that the Cl atom mainly attacks the oxygen atom instead of the nitrogen atom of the NO{sub 2} molecule.

  8. Studies of Trace Gas Chemical Cycles Using Inverse Methods and Global Chemical Transport Models

    NASA Technical Reports Server (NTRS)

    Prinn, Ronald G.

    2003-01-01

    We report progress in the first year, and summarize proposed work for the second year of the three-year dynamical-chemical modeling project devoted to: (a) development, testing, and refining of inverse methods for determining regional and global transient source and sink strengths for long lived gases important in ozone depletion and climate forcing, (b) utilization of inverse methods to determine these source/sink strengths using either MATCH (Model for Atmospheric Transport and Chemistry) which is based on analyzed observed wind fields or back-trajectories computed from these wind fields, (c) determination of global (and perhaps regional) average hydroxyl radical concentrations using inverse methods with multiple titrating gases, and (d) computation of the lifetimes and spatially resolved destruction rates of trace gases using 3D models. Important goals include determination of regional source strengths of methane, nitrous oxide, methyl bromide, and other climatically and chemically important biogenic/anthropogenic trace gases and also of halocarbons restricted by the Montreal protocol and its follow-on agreements and hydrohalocarbons now used as alternatives to the restricted halocarbons.

  9. On Chemical Modeling an Alchemical Process: The Use of Combined Chemical Methods in a Historical Study

    NASA Astrophysics Data System (ADS)

    Rodygin, Mikhail Yu.; Rodygin, Irene V.

    1997-08-01

    Laboratory work is an important component of a course in the History of Chemistry and Alchemy, though it can only be illustrative and not comprehensive. The course should exercise both the cognitive and research abilities of an university student. Therefore methods of modeling are of prime importance at this stage of instruction. Modeling can be both a priori and experimental. The experiment can use the alchemist's materials, or it can reproduce the procedure with modern reagents. A good example for the use of this method is a recipe for the preparation of the Philosopher's Stone attributed to Lullius and cited by J. Ripley in Liber Duodecium Portarum. Thus, the Ripley's recipe is not only considered to be the first indication of the existence of acetone, but it may also indicate the formation of acetyl acetone and its derivatives. Thus, as far as the history of alchemy is concerned, the use of an experimental model not only allows us to solve a number of specific problems such as recipe interpretation and product identification, but it allows also to probe the essence of alchemical work. The combination of empirical and speculative modelings leads to the interaction of the exact methods of chemistry with the broad historico-chemical generalizations, thus introducing some additional dimensions to the definition of historico-chemical practice.

  10. Studies of coupled chemical and catalytic coal conversion methods

    SciTech Connect

    Stock, L.M.

    1988-01-01

    Liquefaction of coal by depolymerization in an organic solvent has been studied for several years. The liquefied coal extract which results from such a process is far more suitable for conversion into liquid fuel by hydrogenolysis than is the untreated coal. Investigations on the chemical structure and the reactive sites of coal can help to select useful reactions for the production of liquids from coal. Sternberg et al. demonstrated that the reductive alkylation method transforms bituminous coal into an enormously soluble substance, irrespective of the mild reaction conditions. The effectiveness of newly introduced alkyl groups for the disruption of intermolecular hydrogen bonds and pi-pi interactions between the aromatic sheets in coal macromolecules has been recognized. It has been reported by Ignasiak et al. that a C-alkylabon reaction using sodium or potassium amide in liquid ammonia can be used to introduce alkyl groups at acidic carbon sites. A method has been developed recently in this laboratory for the solubilization of high rank coals. In the previous reports it was shown that n-butyl lithium and potassium t-butoxide in refluxing heptane produced coal anions which could be alkylated with different alkyl halides. Such alkylated coals were soluble up to 92% in solvents like pyridine. Though the solubilization of coal depended very much on the length of the alkyl group, it also depended very much on the nature of the base used. Strong bases like n-butyl lithium (pKa=42) can cause proton abstraction from aromatic structures, if the more acidic benzylic protons are absent. The utility of this procedure, initially developed and used by Miyake and Stock, has now been tested with the high oxygen containing, low rank Illinois No. 6 and Wyodak coals.

  11. Physical and chemical studies of chlorophyll in microemulsions. Progress report

    SciTech Connect

    1980-01-01

    Studies designed to provide fundamental information on both the nature of photoreactions in microemulsions and the utility of these media as solvents for absorbers of solar energy were conducted. As a test system, the photoreduction of absorbed dye (principally methyl red) sensitized by chlorophyll a in an anionic mineral oil in water microemulsion was investiged. Using ascorbate as the water soluble reducing agent and pigment concentrations of up to eight per drop (10mM), the reaction exhibits a pseudo zero order dependence on methyl red. The effect of sensitizer, ascorbate concentration and light intensity on the quantum yield was examined, as well as the effect of varying the microemulsion charge type, product catalysis, and the use of synthetic porphyrin sensitizers. In microemulsions containing up to eight chlorophyll molecules per microdroplet, the quantum yield remains constant over five orders of magnitude concentration. The intrinsic quantum yield is independent of droplet surface charge, but is dependent on pH. One of the products of the chemical reduction of methyl red, N, N-dimethyl-p-phenylenediamine (DMPD), increases the limiting quantum yield two to three fold. Synthetic porphyrins have been found to act as sensitizers, and a number of tetrapyridyl porphyrin derivatives containing one to four carbon chains of varying length have been made and examined. The results show that the quantum yield increases with increasing chain length for the monoalkyl compounds, and also indicate the possible involvement of a sensitizer orientation effect. The transport of oil soluble electroactive species in nonionic microemulsions has been found to exhibit percolation behavior, which has potential photogalvanic applications.

  12. Role of phosphorus in lunar samples: a chemical study

    SciTech Connect

    Jovanovic, S.; Reed, G.W. Jr.

    1982-01-01

    The roles played by phosphorus present in lunar material may be important in understanding the evolution of the crustal rocks. Quantitative extraction of phosphorus and trace elements associated with possible phosphate phases is the ultimate objective of these studies. Because P may be present in glassy or microcrystalline mesostasis and also as discrete phosphate minerals and as phosphides, chemical procedures provide a tool for its determination along with its complements of trace elements. In these experiments 0.1 M acid was used as a phosphate-specific agent. One experiment was designed to measure how quantitatively P-related constituents are extracted. In consecutive leaching steps more p and REE were dissolved, 76 vs 26% P and 64 vs 37% Sm, from the finer grain sample split. This could be a grain size effect or it could be due to phase separations. Only small amounts of soluble phases remained after the initial 10 minute extraction. Phosphorus and REE are dilute acid soluble in amounts ranging up to 70%. They have sympathetically but are not necessarily highly correlated. Acid soluble fractions of KREEP-rich breccia 14312 and highland breccia 66095 matrix and melt rock clast have chondrite normalized REE patterns similar to that of apatite from a terrestrial gabbro. A different pattern is observed for mare basalt 75055 whole rock and pyroxene and an ilmenite-rich separate. The residues after the acid leach are always HREE enriched relative to the leached fractions. No KREEP-like REE/CH pattern was observed. A systematics for highland rocks based on P/sub 2/O/sub 5/ and Al/sub 2/O/sub 3/ is noted. Igneous KREEP rock 15386 and Apollo-16, Fe-rich, high-P/sub 2/O/sub 5/ glasses reported by Powell et al. (1975) play key roles. 5 figures, 1 table.

  13. Results of Chemical Analyses in Support of Yucca Mountain Studies

    SciTech Connect

    Daniels, Jeanette

    2007-12-11

    Ground water monitoring for the Nye County Early Warning Drilling Program (NCEWDP) was established to monitor underground water sources of the area and to protect communities surrounding the Nevada Test Site (NTS) from potential radionuclide contamination of these water sources. It provides hydrological information pertaining to groundwater flow patterns and recharge issues in the vicinity of Yucca Mountain. The Harry Reid Center for Environmental Studies (HRC) obtained groundwater samples from select NCEWDP wells shown in Figure 1. These samples were analyzed for major cations, major anions, trace elements, rare earth elements, alkalinity, pH and conductivity. These geochemical results can be used to evaluate the degree of interaction between the aquifers sampled, leading to a thorough mapping of the aquifer system. With increased analysis down gradient of the Yucca Mountain area, evaluations can identify viable groundwater flow paths and establish mixing of the groundwater systems. Tracer tests provide insight into groundwater flow characteristics and transport processes of potential contaminants. These tests are important for contaminant migration issues including safe disposal of hazardous and radioactive materials and remediation of potentially released contaminants. At a minimum, two conservative (non-sorbing) tracers with different diffusion coefficients are used for each tracer test. The tracer test performed under this cooperative agreement utilized fluorinated benzoic acids and halides as conservative tracers. The tracers are of differing size and have differing rates of diffusion into the rock. Larger molecules can not enter the pore spaces that are penetrated by the smaller molecules, therefore larger tracers will travel faster through thegroundwater system. Identical responses of the two tracers indicate no appreciable diffusion into pores of the aquifer system tuff. For the Nye County Tracer Tests, the HRC provided chemical analysis for the tracer

  14. Second report on the Oak Ridge K-25 Site Biological Monitoring and Abatement Program for Mitchell Branch

    SciTech Connect

    Smith, J.G.; Adams, S.M.; Hinzman, R.L.; Kszos, L.A.; Loar, J.M.; Peterson, M.J.; Ryon, M.G.; Southworth, G.R.; Crumby, W.D.

    1994-03-01

    On September 11, 1986, a modified National Pollutant Discharge Elimination System permit was issued for the Oak Ridge Gaseous Diffusion Plant (ORGDP; now referred to as the Oak Ridge K-25 Site), a former uranium-enrichment production facility. As required in Part III of the permit, a Biological Monitoring and Abatement Program (BMAP) was developed for the biological monitoring of Mitchell Branch (K-1700 stream) and submitted for approval to the US EPA and the Tennessee Department of Environment and Conservation. The plan described biomonitoring activities that would be conducted over the duration of the permit. The objectives of the BMAP are to demonstrate that the effluent limitations established for the Oak Ridge K-25 Site protect and maintain the use of Mitchell Branch for growth and propagation of fish and other aquatic life, and to document the effects on stream biota resulting from operation of major new pollution abatement facilities. The BMAP consists of four tasks: ambient toxicity testing; bioaccumulation studies; biological indicator studies; and ecological surveys of stream communities, including benthic macroinvertebrates and fish. This document is the second in a series of reports presenting the results of the studies that were conducted over various periods of time between August 1987 and June 1990.

  15. STUDIES ON THE SENSITIZATION OF ANIMALS WITH SIMPLE CHEMICAL COMPOUNDS

    PubMed Central

    Landsteiner, K.; Di Somma, A. A.

    1938-01-01

    With the view of making new types of chemicals accessible for investigations on drug hypersensitiveness, methods have been devised for sensitizing animals with diazomethane and mustard oil, two non-aromatic compounds. Guinea pigs have been sensitized to diazomethane, a substance of high reactivity and known to cause severe allergic effects in man. With the second substance, allylisothiocyanate, likewise capable of forming conjugates with substances in the animal body, sensitization effects have been obtained in man and in hogs. Sensitization in human beings was successful with one out of six individuals treated. The observations indicate species and individual differences as regards the ability to become sensitized to various chemical compounds. PMID:19870801

  16. Laser studies of chemical reaction and collision processes

    SciTech Connect

    Flynn, G.

    1993-12-01

    This work has concentrated on several interrelated projects in the area of laser photochemistry and photophysics which impinge on a variety of questions in combustion chemistry and general chemical kinetics. Infrared diode laser probes of the quenching of molecules with {open_quotes}chemically significant{close_quotes} amounts of energy in which the energy transferred to the quencher has, for the first time, been separated into its vibrational, rotational, and translational components. Probes of quantum state distributions and velocity profiles for atomic fragments produced in photodissociation reactions have been explored for iodine chloride.

  17. Organic Contaminant Abatement in Reclaimed Water by UV/H2O2 and a Combined Process Consisting of O3/H2O2 Followed by UV/H2O2: Prediction of Abatement Efficiency, Energy Consumption, and Byproduct Formation.

    PubMed

    Lee, Yunho; Gerrity, Daniel; Lee, Minju; Gamage, Sujanie; Pisarenko, Aleksey; Trenholm, Rebecca A; Canonica, Silvio; Snyder, Shane A; von Gunten, Urs

    2016-04-01

    UV/H2O2 processes can be applied to improve the quality of effluents from municipal wastewater treatment plants by attenuating trace organic contaminants (micropollutants). This study presents a kinetic model based on UV photolysis parameters, including UV absorption rate and quantum yield, and hydroxyl radical (·OH) oxidation parameters, including second-order rate constants for ·OH reactions and steady-state ·OH concentrations, that can be used to predict micropollutant abatement in wastewater. The UV/H2O2 kinetic model successfully predicted the abatement efficiencies of 16 target micropollutants in bench-scale UV and UV/H2O2 experiments in 10 secondary wastewater effluents. The model was then used to calculate the electric energies required to achieve specific levels of micropollutant abatement in several advanced wastewater treatment scenarios using various combinations of ozone, UV, and H2O2. UV/H2O2 is more energy-intensive than ozonation for abatement of most micropollutants. Nevertheless, UV/H2O2 is not limited by the formation of N-nitrosodimethylamine (NDMA) and bromate whereas ozonation may produce significant concentrations of these oxidation byproducts, as observed in some of the tested wastewater effluents. The combined process of O3/H2O2 followed by UV/H2O2, which may be warranted in some potable reuse applications, can achieve superior micropollutant abatement with reduced energy consumption compared to UV/H2O2 and reduced oxidation byproduct formation (i.e., NDMA and/or bromate) compared to conventional ozonation. PMID:26909504

  18. Studies by the U.S. Geological Survey on sources, transport, and fate of agricultural chemicals

    USGS Publications Warehouse

    Capel, Paul D.; Hamilton, Pixie A.; Erwin, Martha L.

    2004-01-01

    Information from these studies will help with decision-making related to chemical use, conservation, and other farming practices that are used to reduce runoff of agricultural chemicals and sediment from fields. This information also will benefit the U.S. Environmental Protection Agency, the Department of Agriculture, local and regional water managers, and agricultural chemical manufacturers who are involved in managing chemical use and pesticide registration.

  19. Chemical Accelerator Studies of Ion-Molecule Reaction Dynamics

    NASA Astrophysics Data System (ADS)

    Zhang, Jingfeng

    1995-01-01

    A chemical accelerator instrument has been used to study the dynamics of ion-molecule reaction processes in the gas phase. Specifically, the following reactions are investigated: eqalign{rm CO^+ + H_2&longrightarrowrm HCO ^+ + Hcrrm CO^+ + D_2& longrightarrowrm DCO^+ + Dcrrm CO^+ + HDlongrightarrow &rm HCO ^+ (DCO^+) + D (H)cr} . Both angular and velocity distributions of reactively scattered product ions are measured, as well as reaction cross sections as a function of reactant relative translational energy. Formation of HCO^+ ion from rm CO^+ + H_2 over the collision energy range from 0.35 to 3.02 eV (c.m.) follows closely the predictions of the spectator stripping model, and results in highly excited HCO^+ product ions. This reaction is found to proceed via a direct impulsive mechanism, without any long-lived intermediate complexes involved. The reaction cross section is proportional to E_{T} ^{-1/2}, where E_ {rm T} is the reactant ion relative translational energy. Deuterium atom transfer from D_2 to CO^+ over the collision energy range from 0.41 to 5.14 eV (c.m.) occurs also in a direct process. Reaction cross section is proportional to rm E_{T}^{ -1/2}. The results are very similar to those of the reaction rm CO^+ + H_2. The reaction CO^+ + HD has two product channels, leading to the formation of HCO ^+ and DCO^+, respectively. The reaction is studied over the energy range from 0.88 to 5.00 eV (c.m.). It is found that the production of HCO^+ is consistently the slightly favored reaction channel, which is attributed to the orientation isotope effect. The translational exoergicity for both reaction channels follows closely the prediction of spectator stripping model. Product DCO^+ ions are in higher excited states than HCO ^+ ions. Product velocity distribution contour maps indicate that, at the lowest energies, the DCO ^+ production channel has a longer reaction duration than the HCO^+ production channel, but both reaction channels are dominated by direct

  20. GENE INDUCTION STUDIES AND TOXICITY OF CHEMICAL MIXTURES

    EPA Science Inventory

    As part of its mixtures program the Agency for Toxic Substances and Disease Registry (ATSDR) supports in vitro and limited in vivo toxicity testing to further our understanding of the toxicity and health effects of chemical mixtures. There are increasing concerns that environment...

  1. Third report on the Oak Ridge K-25 Site Biological Monitoring and Abatement Program for Mitchell Branch

    SciTech Connect

    Hinzman, R.L.; Adams, S.M.; Ashwood, T.L.

    1995-08-01

    As a condition of the modified National Pollutant Discharge Elimination System (NPDES) permit issued to the Oak Ridge Gaseous Diffusion Plant (ORGDP; now referred to as the Oak Ridge K-25 Site) on September 11, 1986, a Biological Monitoring and Abatement Program (BMAP) was developed for the receiving stream (Mitchell Branch or K-1700 stream). On October 1, 1992, a renewed NPDES permit was issued for the K-25 Site. A biological monitoring plan was submitted for Mitchell Branch, Poplar Creek, Poplar Creek Embayment of the Clinch River and any unnamed tributaries of these streams. The objectives of BMAP are to (1) demonstrate that the effluent limitations established for the Oak Ridge K-25 Site protect and maintain the use of Mitchell Branch for growth and propagation of fish and other aquatic life and (2) document the effects on stream biota resulting from operation of major new pollution abatement facilities, including the Central Neutralization Facility (CNF) and the Toxic Substances Control Act (TSCA) incinerator. The BMAP consists of four tasks: (1) toxicity monitoring; (2) bioaccumulation monitoring; (3) assessment of fish health; and (4) instream monitoring of biological communities, including benthic macroinvertebrates and fish. This document, the third in a series, reports on the results of the Oak Ridge K-25 Site BMAP; it describes studies that were conducted over various periods of time between June 1990 and December 1993, although monitoring conducted outside this time period is included, as appropriate.

  2. Nitrogen oxide abatement by distributed fuel addition. Quarterly report No. 2, November 1, 1987--January 31, 1988

    SciTech Connect

    Wendt, J.O.L.; Meraab, J.

    1988-03-25

    The purpose of this project is to develop techniques for nitrogen oxides abatement by distributed fuel addition. The major nitrogen oxide of interest is Nitric Oxide (NO), a precursor to premature forest damage and to acid rain. Recently interest has also been evoked with respect to an additional oxide of nitrogen, namely Nitrous Oxide (N{sub 2}O). Therefore, abatement measures for NO{sub x} are being investigated to determine their influence on N{sub 2}O as well. This report briefly describes the significance of N{sub 2}O emissions to the environment and the urgent need to develop techniques that can reduce emissions of both NO and N{sub 2}O. Reburning through distributed fuel addition may be an effective technique for NO{sub x} (mainly NO) emission control as described in the previous quarterly report. Reburning may also be effective in reducing N{sub 2}O levels. A technique for N{sub 2}O measurement by gas chromatography/electron capture detection was developed during this quarter, and is described in this report. This analysis technique will be used in the proposed experimental study to investigate the effectiveness of reburning on N{sub 2}O control.

  3. Accelerating Wave Function Convergence in Interactive Quantum Chemical Reactivity Studies.

    PubMed

    Mühlbach, Adrian H; Vaucher, Alain C; Reiher, Markus

    2016-03-01

    The inherently high computational cost of iterative self-consistent field (SCF) methods proves to be a critical issue delaying visual and haptic feedback in real-time quantum chemistry. In this work, we introduce two schemes for SCF acceleration. They provide a guess for the initial density matrix of the SCF procedure generated by extrapolation techniques. SCF optimizations then converge in fewer iterations, which decreases the execution time of the SCF optimization procedure. To benchmark the proposed propagation schemes, we developed a test bed for performing quantum chemical calculations on sequences of molecular structures mimicking real-time quantum chemical explorations. Explorations of a set of six model reactions employing the semi-empirical methods PM6 and DFTB3 in this testing environment showed that the proposed propagation schemes achieved speedups of up to 30% as a consequence of a reduced number of SCF iterations. PMID:26788887

  4. Chemical Studies on Polyoma and Shope Papilloma Viruses

    PubMed Central

    Kass, Sidney J.

    1970-01-01

    Polyoma and Shope papilloma viruses were purified and analyzed by chemical and physical methods. Disc electrophoresis of degraded virions indicated the presence, in both cases, of only one major species of polypeptide subunit. The weight of the peptide chain of polyoma virus was estimated in 8 m urea to be about 45,000 avograms, based on the sedimentation rate in a sucrose-urea gradient and the diffusion coefficient estimated from the differential migration in electrophoresis in gels of different pore size. The presence of a minor peptide of smaller size was suggested by carboxyl-terminal and sedimentation analyses. The amino acid composition of polyoma capsid protein was reported. Chemical analyses showed that polyoma virus and Shope papilloma virus contained 16 and 17.5% deoxyribonucleic acid, respectively. Light scattering by the polyoma virion showed it to have a molecular weight of 22 × 106 and a diameter of 54 nm. Images PMID:4314556

  5. [Study on the chemical components of Rabdosia excisa].

    PubMed

    Zhang, N; Li, C; Yi, X

    1998-07-01

    Four kinds of components were extracted and separated from the stems and leaves of Rabdosia excisa. They had been identified as Kamebakaurin, Ursolic acid, Daucosterol and Liquiritin respectively by physical and chemical methods, as well as spectrum data. It was first time that Liquiritin was obtained from the Robdosia family, and its 13C-NMR data of Liquiritin had not been reported before. PMID:12569856

  6. Studies on marine toxins: chemical and biological aspects

    NASA Astrophysics Data System (ADS)

    Stonik, Valentin A.; Stonik, Inna V.

    2010-07-01

    The structures and mechanisms of biological action of the best known representatives of the main groups of marine toxins are presented. It is shown that many compounds have complex chemical structures and possess extremely high toxicities. Characteristic features of isolation, structure determination and syntheses of these compounds using the achievement of modern organic chemistry are discussed. The methods of identification and quantitative analysis of marine toxins are briefly reviewed.

  7. Chemical and pharmacological studies of the plants from genus Celastrus.

    PubMed

    Su, Xiao-Hui; Zhang, Man-Li; Zhan, Wen-Hong; Huo, Chang-Hong; Shi, Qing-Wen; Gu, Yu-Cheng; Kiyota, Hiromasa

    2009-02-01

    The plants of genus Celastrus, distributed in Asia, have been used as natural insecticides and folk medicines to treat fever, chill, joint pain, edema, rheumatoid arthritis, and bacterial infection in China for a long time. This contribution reviews the chemical constituents, isolated from the plants in genus Celastrus in the past few decades, and their biological activities. The compounds listed are sesquiterpenes (beta-agarofurans), diterpenes, triterpenes, alkaloids, and flavonoids. PMID:19235157

  8. Abatement of waste gases and water during the processes of semiconductor fabrication.

    PubMed

    Wen, Rui-mei; Liang, Jun-wu

    2002-10-01

    The purpose of this article is to examine the methods and equipment for abating waste gases and water produced during the manufacture of semiconductor materials and devices. Three separating methods and equipment are used to control three different groups of electronic wastes. The first group includes arsine and phosphine emitted during the processes of semiconductor materials manufacture. The abatement procedure for this group of pollutants consists of adding iodates, cupric and manganese salts to a multiple shower tower (MST) structure. The second group includes pollutants containing arsenic, phosphorus, HF, HCl, NO2, and SO3 emitted during the manufacture of semiconductor materials and devices. The abatement procedure involves mixing oxidants and bases in an oval column with a separator in the middle. The third group consists of the ions of As, P and heavy metals contained in the waste water. The abatement procedure includes adding CaCO3 and ferric salts in a flocculation-sedimentation compact device equipment. Test results showed that all waste gases and water after the abatement procedures presented in this article passed the discharge standards set by the State Environmental Protection Administration of China. PMID:12491721

  9. Save water to save carbon and money: developing abatement costs for expanded greenhouse gas reduction portfolios.

    PubMed

    Stokes, Jennifer R; Hendrickson, Thomas P; Horvath, Arpad

    2014-12-01

    The water-energy nexus is of growing interest for researchers and policy makers because the two critical resources are interdependent. Their provision and consumption contribute to climate change through the release of greenhouse gases (GHGs). This research considers the potential for conserving both energy and water resources by measuring the life-cycle economic efficiency of greenhouse gas reductions through the water loss control technologies of pressure management and leak management. These costs are compared to other GHG abatement technologies: lighting, building insulation, electricity generation, and passenger transportation. Each cost is calculated using a bottom-up approach where regional and temporal variations for three different California water utilities are applied to all alternatives. The costs and abatement potential for each technology are displayed on an environmental abatement cost curve. The results reveal that water loss control can reduce GHGs at lower cost than other technologies and well below California's expected carbon trading price floor. One utility with an energy-intensive water supply could abate 135,000 Mg of GHGs between 2014 and 2035 and save--rather than spend--more than $130/Mg using the water loss control strategies evaluated. Water loss control technologies therefore should be considered in GHG abatement portfolios for utilities and policy makers. PMID:25369123

  10. Efficiency of final cleaning for lead-based paint abatement in indoor environments.

    PubMed

    Grinshpun, Sergey A; Choe, Kyoo T; Trunov, Mikhaylo; Willeke, Klaus; Menrath, William; Friedman, Warren

    2002-03-01

    The effectiveness of procedures used for the final indoor cleaning after active lead-based paint abatement were evaluated in a 830 ft3 test chamber. Dry and wet scraping and dry machine sanding were applied to wooden doors obtained from lead-hazard control sites. The airborne particle concentration and size distribution were monitored using a real-time particle size spectrometer. Particulates were also collected on filters and analyzed for total dust and lead. The resulting airborne lead mass was determined for each cleaning procedure, and the potential floor lead loading resulting from the dust settling was calculated. Wipe samples were collected to measure the actual floor lead loading. The effectiveness of final cleaning was evaluated first for dry abatement methods. Various cleaning work practices were tested by applying wet and dry debris sweeping as well as no sweeping in combinations with wet and dry removal of plastic sheeting. Considerable resuspension of leaded particles was detected during dry sweeping: the airborne lead mass increase ranged between 65 and 220 percent. However, this increase did not exceed 22 percent when wet sweeping was applied. Minimal or no resuspension was found when the plastic was folded with leaded debris inside (no sweeping was performed prior to the sheeting removal). During folding activity, the "clean" (uncovered) floor surface may be significantly contaminated with leaded dust from workers' shoes and cleaning tools. The first HEPA vacuuming resulted in a 15- to 20-fold decrease of the airborne lead mass; however, it was not sufficient to reduce the floor lead loading to the U.S. Department of Housing and Urban Development (HUD) clearance level of 40 microg/ft2, as determined by wipe sampling. Wet mopping following the first HEPA vacuuming was proven to be effective to reduce the lead loading significantly below 40 microg/ft2. The second HEPA vacuuming resulted in further reduction of the airborne lead mass concentration. The

  11. Photocatalytic abatement results from a model street canyon.

    PubMed

    Gallus, M; Ciuraru, R; Mothes, F; Akylas, V; Barmpas, F; Beeldens, A; Bernard, F; Boonen, E; Boréave, A; Cazaunau, M; Charbonnel, N; Chen, H; Daële, V; Dupart, Y; Gaimoz, C; Grosselin, B; Herrmann, H; Ifang, S; Kurtenbach, R; Maille, M; Marjanovic, I; Michoud, V; Mellouki, A; Miet, K; Moussiopoulos, N; Poulain, L; Zapf, P; George, C; Doussin, J F; Kleffmann, J

    2015-11-01

    During the European Life+ project PhotoPAQ (Demonstration of Photocatalytic remediation Processes on Air Quality), photocatalytic remediation of nitrogen oxides (NOx), ozone (O3), volatile organic compounds (VOCs), and airborne particles on photocatalytic cementitious coating materials was studied in an artificial street canyon setup by comparing with a colocated nonactive reference canyon of the same dimension (5 × 5 × 53 m). Although the photocatalytic material showed reasonably high activity in laboratory studies, no significant reduction of NOx, O3, and VOCs and no impact on particle mass, size distribution, and chemical composition were observed in the field campaign. When comparing nighttime and daytime correlation plots of the two canyons, an average upper limit NOx remediation of ≤2% was derived. This result is consistent only with three recent field studies on photocatalytic NOx remediation in the urban atmosphere, whereas much higher reductions were obtained in most other field investigations. Reasons for the controversial results are discussed, and a more consistent picture of the quantitative remediation is obtained after extrapolation of the results from the various field campaigns to realistic main urban street canyon conditions. PMID:26178827

  12. Greenhouse Gas Abatement with Distributed Generation in California's Commercial Buildings

    SciTech Connect

    Stadler, Michael; Marnay, Chris; Cardoso, Goncalo; Megel, Olivier; Siddiqui, Afzal; Lai, Judy

    2009-08-15

    Lawrence Berkeley National Laboratory (LBL) is working with the California Energy Commission (CEC) to determine the role of distributed generation (DG) in greenhouse gas reductions. The impact of DG on large industrial sites is well known, and mostly, the potentials are already harvested. In contrast, little is known about the impact of DG on commercial buildings with peak electric loads ranging from 100 kW to 5 MW. We examine how DG with combined heat and power (CHP) may be implemented within the context of a cost minimizing microgrid that is able to adopt and operate various smart energy technologies, such as thermal and photovoltaic (PV) on-site generation, heat exchangers, solar thermal collectors, absorption chillers, and storage systems. We use a mixed-integer linear program (MILP) that has the minimization of a site's annual energy costs as objective. Using 138 representative commercial sites in California (CA) with existing tariff rates and technology data, we find the greenhouse gas reduction potential for California's commercial sector. This paper shows results from the ongoing research project and finished work from a two year U.S. Department of Energy research project. To show the impact of the different technologies on CO2 emissions, several sensitivity runs for different climate zones within CA with different technology performance expectations for 2020 were performed. The considered sites can contribute between 1 Mt/a and 1.8 Mt/a to the California Air Resources Board (CARB) goal of 6.7Mt/a CO2 abatement potential in 2020. Also, with lower PV and storage costs as well as consideration of a CO2 pricing scheme, our results indicate that PV and electric storage adoption can compete rather than supplement each other when the tariff structure and costs of electricity supply have been taken into consideration. To satisfy the site's objective of minimizing energy costs, the batteries will be charged also by CHP systems during off-peak and mid-peak hours and

  13. Tannin extracts abate ammonia emissions from simulated dairy barn floors.

    PubMed

    Powell, J M; Aguerre, M J; Wattiaux, M A

    2011-01-01

    Feeding more tannin and less crude protein (CP) to dairy cows may have synergistic impacts on reducing NH emissions from dairy barns. Three trials using lab-scale ventilated chambers with concrete floors were conducted to determine the impacts on NH emission of tannin and CP feeding, tannin feeding on urease activity in feces, and tannin application directly to the barn floor. For Trial 1, mixtures of feces and urine from lactating Holstein dairy cows () fed four levels (g kg) of dietary tannin extract [a mixture from red quebracho () and chestnut () trees]: 0 tannin (0T), 4.5 (low tannin [LT]), 9.0 (medium tannin [MT]), and 18.0 (high tannin [HT]); each fed at two levels (g kg) of dietary CP: 155 low CP (LCP) and 168 high CP (HCP) were applied to chambers. For Trial 2, urea solution was added to feces obtained from cows fed 0T, MT, and HT at HCP. For Trial 3, tannin amounts equivalent to those fed at 0T, MT, and HT were applied directly to feces-urine mixtures from 0T-HCP. For all trials, NH emissions were measured 1, 3, 6, 12, 24, 36, and 48 h after treatment application. For Trial 1, reductions in NH emission due to tannin feeding were greatest when fed at LCP: The LCP-LT and LCP-HT treatments emitted 30.6% less NH than LCP-0T, and the HCP-LT and HCP-HT treatments emitted 16.3% less NH than HCP-0T. For Trial 2, feeding tannin decreased urease activity in feces, resulting in an 11.5% reduction in cumulative NH loss. For Trial 3, the application of tannin directly to simulated barn floors also apparently decreased urease activity, resulting in an average reduction in cumulative NH emissions of 19.0%. Larger-scale trails are required to ascertain the effectiveness of tannin extracts in abating NH loss from dairy barn floors. PMID:21546676

  14. Factors associated with chemical burns in Zhejiang province, China: An epidemiological study

    PubMed Central

    2011-01-01

    Background Work-related burns are common among occupational injuries. Zhejiang Province is an industrial area with a high incidence of chemical burns. We aimed to survey epidemiological features of chemical burns in Zhejiang province to determine associated factors and acquire data for developing a strategy to prevent and treat chemical burns. Methods Questionnaires were developed, reviewed and validated by experts, and sent to 25 hospitals in Zhejiang province to prospectively collect data of 492 chemical burn patients admitted during one year from Sept. 1, 2008 to Aug. 31, 2009. Questions included victims' characteristics and general condition, injury location, causes of accident, causative chemicals, total body surface area burn, concomitant injuries, employee safety training, and awareness level of protective measures. Surveys were completed for each of burn patients by burn department personnel who interviewed the hospitalized patients. Results In this study, 417 victims (87.61%) got chemical burn at work, of which 355 victims (74.58%) worked in private or individual enterprises. Most frequent chemicals involved were hydrofluoric acid and sulfuric acid. Main causes of chemical injury accidents were inappropriate operation of equipment or handling of chemicals and absence of or failure to use effective individual protection. Conclusions Most chemical burns are preventable occupational injuries that can be attributed to inappropriate operation of equipment or handling of chemicals, lack of employee awareness about appropriate action and lack of effective protective equipment and training. Emphasis on safety education and protection for workers may help protect workers and prevent chemical burns. PMID:21958110

  15. ALTERNATIVE AND ENHANCED CHEMICAL CLEANING: BASIC STUDIES RESULTS FY2010

    SciTech Connect

    King, W.; Hay, M.

    2011-01-24

    In an effort to develop and optimize chemical cleaning methods for the removal of sludge heels from High Level Waste tanks, solubility tests have been conducted using nonradioactive, pure metal phases. The metal phases studied included the aluminum phase gibbsite and the iron phases hematite, maghemite, goethite, lepidocrocite, magnetite, and wustite. Many of these mineral phases have been identified in radioactive, High Level Waste sludge at the Savannah River and Hanford Sites. Acids evaluated for dissolution included oxalic, nitric, and sulfuric acids and a variety of other complexing organic acids. The results of the solubility tests indicate that mixtures of oxalic acid with either nitric or sulfuric acid are the most effective cleaning solutions for the dissolution of the primary metal phases in sludge waste. Based on the results, optimized conditions for hematite dissolution in oxalic acid were selected using nitric or sulfuric acid as a supplemental proton source. Electrochemical corrosion studies were also conducted (reported separately; Wiersma, 2010) with oxalic/mineral acid mixtures to evaluate the effects of these solutions on waste tank integrity. The following specific conclusions can be drawn from the test results: (1) Oxalic acid was shown to be superior to all of the other organic acids evaluated in promoting the dissolution of the primary sludge phases. (2) All iron phases showed similar solubility trends in oxalic acid versus pH, with hematite exhibiting the lowest solubility and the slowest dissolution. (3) Greater than 90% hematite dissolution occurred in oxalic/nitric acid mixtures within one week for two hematite sources and within three weeks for a third hematite sample with a larger average particle size. This dissolution rate appears acceptable for waste tank cleaning applications. (4) Stoichiometric dissolution of iron phases in oxalic acid (based on the oxalate concentration) and the formation of the preferred 1:1 Fe to oxalate complex

  16. Oak Ridge Y-12 Plant biological monitoring and abatement program (BMAP) plan

    SciTech Connect

    Adams, S.M.; Brandt, C.C.; Cicerone, D.S.

    1998-02-01

    The proposed Biological Monitoring and Abatement Program (BMAP) for East Fork Poplar Creek (EFPC) at the Oak Ridge Y-12 Plant, as described, will be conducted for the duration of the National Pollutant Discharge Elimination System permit issued for the Y-12 Plant on April 28, 1995, and which became effective July 1, 1995. The basic approach to biological monitoring used in this program was developed by the staff in the Environmental Sciences Division at the Oak Ridge National Laboratory at the request of Y-12 Plant personnel. The proposed BMAP plan is based on results of biological monitoring conducted since 1985. Details of the specific procedures used in the current routine monitoring program are provided, but experimental designs for future studies are described in less detail. The overall strategy used in developing this plan was, and continues to be, to use the results obtained from each task to define the scope of future monitoring efforts. Such efforts may require more intensive sampling than initially proposed in some areas or a reduction in sampling intensity in others. By using the results of previous monitoring efforts to define the current program and to guide them in the development of future studies, an effective integrated monitoring program has been developed to assess the impacts of the Y-12 Plant operation on the biota of EFPC and to document the ecological effects of remedial actions.

  17. First annual report on the Biological Monitoring and Abatement Program at Oak Ridge National Laboratory

    SciTech Connect

    Loar, J. M.; Adams, S. M.; Blaylock, B. G.; Boston, H. L.; Frank, M. L.; Garten, C. T.; Houston, M. A.; Kimmel, B. L.; Ryon, M. G.; Smith, J. G.; Southworth, G. R.; Stewart, A. J.; Walton, B. T.; Berry, J. B.; Talmage, S. S.; Amano, H.; Jimenez, B. D.; Kitchings, J. T.; Meyers-Schoene, L.; Mohrbacher, D. A.; Olsen, C. R.

    1992-08-01

    As a condition of the National Pollutant Discharge Elimination System (NPDES) permit issued to Oak Ridge National Laboratory (ORNL) on April 1, 1986, a Biological Monitoring and Abatement Program (BMAP) was developed for White Oak Creek (WOC); selected tributaries of WOC, including Fifth Creek, First Creek, Melton Branch, and Northwest Tributary; and the Clinch River. BMAP consists of seven major tasks that address both radiological and nonradiological contaminants in the aquatic and terrestrial environs on-site and the aquatic environs off-site. These tasks are (1) toxicity monitoring; (2) bioaccumulation monitoring of nonradiological contaminants in aquatic biota; (3) biological indicator studies; (4) instream ecological monitoring; (5) assessment of contaminants in the terrestrial environment; (6) radioecology of WOC and White Oak Lake (WOL); and (7) contaminant transport, distribution, and fate in the WOC embayment-Clinch River-Watts Bar Reservoir system. This document, the first of a series of annual reports presenting the results of BMAP, describes studies that were conducted from March through December 1986.

  18. Bandwidth Study on Energy Use and Potential Energy Saving Opportunities in U.S. Chemical Manufacturing

    SciTech Connect

    Sabine Brueske, Caroline Kramer, Aaron Fisher

    2015-06-01

    Energy bandwidth studies of U.S. manufacturing sectors can serve as foundational references in framing the range (or bandwidth) of potential energy savings opportunities. This bandwidth study examines energy consumption and potential energy savings opportunities in U.S. chemical manufacturing. The study relies on multiple sources to estimate the energy used in the production of 74 individual chemicals, representing 57% of sector-wide energy consumption. Energy savings opportunities for individual chemicals and for 15 subsectors of chemicals manufacturing are based on technologies currently in use or under development; these potential savings are then extrapolated to estimate sector-wide energy savings opportunity.

  19. [Studies on the chemical constitutens of Vicia amoena Fisch].

    PubMed

    Wei, F; Yan, W M

    1997-10-01

    One new flavonoide was isolated from Vicia amoena Fisch. On the basis of spectral (UV, MS, NMR) and chemical reactions, it was elucidated to be kaempferol-3-O-beta-D-mannoside, named amoenin(A3). Moreover, five known compounds have been isolated and identified as quercetin, kaempferol, quercetin-3-O-alpha-L-rhamoside, quercetin-3-O-beta-D-glucoside, kaempferol-3, 7-O-alpha-L-dirhamoside. The total flavonoides showed significant effects on inducing hyperlipidemia and increasing micro-blood vessel elasticity. PMID:11596220

  20. Fundamental studies of chemical vapor deposition diamond growth processes

    SciTech Connect

    Shaw, R.W.; Whitten, W.B.; Ramsey, J.M.; Heatherly, L.

    1991-01-01

    We are developing laser spectroscopic techniques to foster a fundamental understanding of diamond film growth by hot filament chemical vapor deposition (CVD). Several spectroscopic techniques are under investigation to identify intermediate species present in the bulk reactor volume, the thin active volume immediately above the growing film, and the actual growing surface. Such a comprehensive examination of the overall deposition process is necessary because a combination of gas phase and surface chemistry is probably operating. Resonantly enhanced multiphoton ionization (REMPI) techniques have been emphasized. A growth rector that permits through-the-substrate gas sampling for REMPI/time-of-flight mass spectroscopy has been developed. 7 refs., 2 figs.

  1. [Study on chemical constituents of Drosera peltata var. multisepala].

    PubMed

    Li, Lin; Huang, Jin; Xu, Xianghua; Zhang, Yao; Cheng, Kejun; Yu, Peizhong

    2012-01-01

    Chemical investigatation of Drosera peltata var. multisepala led to the isolation of eleven compounds using various chromatographic techniques. The structures of these compounds were elucidated as isoshinanolone-4-O-beta-D-glucoside (1), isoshinanolone (2), epi-isoshinanolone (3), plumbagin (4), droserone (5), droserone-5-O-glucoside (6), quercetin (7), kaempferol (8) , gossypetin-8-O-glucoside (9), 3,3'-dimethoxy ellagic acid (10), and ellagic acid (11) by their physicochemical properties and spectral data analysis. Compound 1 was a new compound. Compounds 3, 8, 10, and 11 were isolated from this plant for the first time. PMID:22737855

  2. Biological and chemical studies on overheated brewed coffee.

    PubMed

    Sasaki, Y; Shibamoto, T; Wei, C I; Fernando, S

    1987-03-01

    Vapour formed from overheated decaffeinated coffee was condensed and tested for mutagenicity using the Ames assay in Salmonella typhimurium strains TA98 and TA100. Vapour produced at 73 and 100 degrees C exhibited no mutagenicity. The basic fraction of vapour produced at 350 degrees C showed weak mutagenicity towards strains TA98 with metabolic activation. The chemical analysis of this fraction identified pyridines and pyrazines as the major constituents. None of the compounds identified in this fraction has been reported as mutagenic when tested in the Ames assay. PMID:3570110

  3. IR spectroscopic study of the chemical composition of epiphytic lichens

    NASA Astrophysics Data System (ADS)

    Meysurova, A. F.; Khizhnyak, S. D.; Pakhomov, P. M.

    2011-11-01

    Changes in the chemical composition of lichens exposed to pollutants are investigated by means of FTIR spectroscopy. According to model experiments, alkyl nitrates, ammonium salts, amines, and sulfones develop in the lichen thallus through the action of ammonia and nitric and sulfuric acids. Spectroscopic data of modeling experiments enabled nitrogen- and sulfur-containing substances to be identified as the main air pollutants in the vicinity of a pig-breeding complex and information to be obtained on the content of the pollutants and their impact on the lichens.

  4. α-Anilinoketones, Esters and Amides: A Chemical Study

    PubMed Central

    Qandil, Amjad M.; Fakhouri, Lara I.

    2012-01-01

    A group of α-anilinoketones, 2-aminoalcohols, α-anilinoesters and α-anilinoamides were successfully synthesized and characterized by NMR spectroscopy and mass spectrometry. The yields were, in general, moderate to good (up to 75.4%), except for the α-anilinoesters (16.9–35.6%). The α-halocarbonyl starting materials showed different chemical reactivities. α-Haloketones and α-chloroacetates afforded monoalkylation, while small α-chloroamides afforded dialkylation. Finally, NMR spectroscopy revealed interesting structural features about the 2-aminoalcohols and diphenylamides. PMID:24281663

  5. Comparison of two head-up displays in simulated standard and noise abatement night visual approaches

    NASA Technical Reports Server (NTRS)

    Cronn, F.; Palmer, E. A., III

    1975-01-01

    Situation and command head-up displays were evaluated for both standard and two segment noise abatement night visual approaches in a fixed base simulation of a DC-8 transport aircraft. The situation display provided glide slope and pitch attitude information. The command display provided glide slope information and flight path commands to capture a 3 deg glide slope. Landing approaches were flown in both zero wind and wind shear conditions. For both standard and noise abatement approaches, the situation display provided greater glidepath accuracy in the initial phase of the landing approaches, whereas the command display was more effective in the final approach phase. Glidepath accuracy was greater for the standard approaches than for the noise abatement approaches in all phases of the landing approach. Most of the pilots preferred the command display and the standard approach. Substantial agreement was found between each pilot's judgment of his performance and his actual performance.

  6. Quantum Chemical Study of the Thermochemical Properties of Organophosphorous Compounds.

    PubMed

    Khalfa, A; Ferrari, M; Fournet, R; Sirjean, B; Verdier, L; Glaude, P A

    2015-10-22

    Organophosphorous compounds are involved in many toxic compounds such as fungicides, pesticides, or chemical warfare nerve agents. The understanding of the decomposition chemistry of these compounds in the environment is largely limited by the scarcity of thermochemical data. Because of the high toxicity of many of these molecules, experimental determination of their thermochemical properties is very difficult. In this work, standard gas-phase thermodynamic data, i.e., enthalpies of formation (ΔfH298°), standard entropies (S298°), and heat capacities (Cp°(T)), were determined using quantum chemical calculations and more specifically the CBS-QB3 composite method, which was found to be the best compromise between precision and calculation time among high accuracy composite methods. A large number of molecules was theoretically investigated, involving trivalent and pentavalent phosphorus atoms, and C, H, O, N, S, and F atoms. These data were used to propose 83 original groups, used in the semiempirical group contribution method proposed by Benson. Thanks to these latter group values, thermochemical properties of several nerve agents, common pesticides and herbicides have been evaluated. Bond dissociations energies (BDE), useful for the analysis the thermal stability of the compounds, were also determined in several molecules of interest. PMID:26434606

  7. Chemical Biology Applied to the Study of Bacterial Pathogens

    PubMed Central

    Anthouard, Rebecca

    2014-01-01

    In recent years, chemical biology and chemical genomics have been increasingly applied to the field of microbiology to uncover new potential therapeutics as well as to probe virulence mechanisms in pathogens. The approach offers some clear advantages, as identified compounds (i) can serve as a proof of principle for the applicability of drugs to specific targets; (ii) can serve as conditional effectors to explore the function of their targets in vitro and in vivo; (iii) can be used to modulate gene expression in otherwise genetically intractable organisms; and (iv) can be tailored to a narrow or broad range of bacteria. This review highlights recent examples from the literature to illustrate how the use of small molecules has advanced discovery of novel potential treatments and has been applied to explore biological mechanisms underlying pathogenicity. We also use these examples to discuss practical considerations that are key to establishing a screening or discovery program. Finally, we discuss the advantages and challenges of different approaches and the methods that are emerging to address these challenges. PMID:25404026

  8. A microwave and quantum chemical study of allyltrifluorosilane

    NASA Astrophysics Data System (ADS)

    Møllendal, H.; Guirgis, G. A.

    2003-04-01

    The structural and conformational properties of allytrifluorsilane, H 2CCH-CH 2-SiF 3, have been explored by microwave (MW) spectroscopy and high-level ab initio and density functional theory quantum chemical calculations. The microwave spectrum was investigated in the 18-62 GHz spectral regions. The a-type R-branch transitions of one conformer were assigned for the ground as well as for 10 vibrationally excited states. The CC-C-Si chain of atoms in this rotamer takes an anti-clinal ('skew') conformation, with a dihedral angle calculated to be 111.6° from the syn-periplanar (0°) conformation. The question whether a CC-C-Si syn-periplanar conformer exists as a high-energy form in the gas phase remains open. In most of the quantum chemical calculations this conformation is predicted to be a transition state. However, in the most advanced calculations (B3LYP/aug-cc-pVTZ level of theory) the syn-periplanar conformer is predicted to be a stable rotamer that is calculated to be 6.5 kJ/mol higher in energy than the anti-clinal form. Since there is no indication in the MW spectrum for the presence of high-energy form(s), it is concluded that the anti-clinal conformer is at least 4 kJ/mol more stable than any other hypothetical rotamer.

  9. Modeling for waste management associated with environmental-impact abatement under uncertainty.

    PubMed

    Li, P; Li, Y P; Huang, G H; Zhang, J L

    2015-04-01

    Municipal solid waste (MSW) treatment can generate significant amounts of pollutants, and thus pose a risk on human health. Besides, in MSW management, various uncertainties exist in the related costs, impact factors, and objectives, which can affect the optimization processes and the decision schemes generated. In this study, a life cycle assessment-based interval-parameter programming (LCA-IPP) method is developed for MSW management associated with environmental-impact abatement under uncertainty. The LCA-IPP can effectively examine the environmental consequences based on a number of environmental impact categories (i.e., greenhouse gas equivalent, acid gas emissions, and respiratory inorganics), through analyzing each life cycle stage and/or major contributing process related to various MSW management activities. It can also tackle uncertainties existed in the related costs, impact factors, and objectives and expressed as interval numbers. Then, the LCA-IPP method is applied to MSW management for the City of Beijing, the capital of China, where energy consumptions and six environmental parameters [i.e., CO2, CO, CH4, NOX, SO2, inhalable particle (PM10)] are used as systematic tool to quantify environmental releases in entire life cycle stage of waste collection, transportation, treatment, and disposal of. Results associated with system cost, environmental impact, and the related policy implication are generated and analyzed. Results can help identify desired alternatives for managing MSW flows, which has advantages in providing compromised schemes under an integrated consideration of economic efficiency and environmental impact under uncertainty. PMID:25516254

  10. Modeling with uncertain science: estimating mitigation credits from abating lead poisoning in Golden Eagles.

    PubMed

    Fitts Cochrane, Jean; Lonsdorf, Eric; Allison, Taber D; Sanders-Reed, Carol A

    2015-09-01

    Challenges arise when renewable energy development triggers "no net loss" policies for protected species, such as where wind energy facilities affect Golden Eagles in the western United States. When established mitigation approaches are insufficient to fully avoid or offset losses, conservation goals may still be achievable through experimental implementation of unproven mitigation methods provided they are analyzed within a framework that deals transparently and rigorously with uncertainty. We developed an approach to quantify and analyze compensatory mitigation that (1) relies on expert opinion elicited in a thoughtful and structured process to design the analysis (models) and supplement available data, (2) builds computational models as hypotheses about cause-effect relationships, (3) represents scientific uncertainty in stochastic model simulations, (4) provides probabilistic predictions of "relative" mortality with and without mitigation, (5) presents results in clear formats useful to applying risk management preferences (regulatory standards) and selecting strategies and levels of mitigation for immediate action, and (6) defines predictive parameters in units that could be monitored effectively, to support experimental adaptive management and reduction in uncertainty. We illustrate the approach with a case study characterized by high uncertainty about underlying biological processes and high conservation interest: estimating the quantitative effects of voluntary strategies to abate lead poisoning in Golden Eagles in Wyoming due to ingestion of spent game hunting ammunition. PMID:26552261

  11. Artificial recharge for subsidence abatement at the NASA-Johnson Space Center, Phase I

    USGS Publications Warehouse

    Garza, Sergio

    1977-01-01

    Regional decline of aquifer head due to ground-water withdrawal in the Houston area has caused extensive land-surface subsidence. The NASA-Johnson Space Center (NASA-JSC) in southeastern Harris County, Texas, was about 13 to 19 feet above mean sea level in 1974 and sinking at a rate of more than 0.2 foot per year. NASA-JSC officials, concerned about the hurricane flooding hazard, requested the U.S. Geological Survey to study the feasibility of artificially recharging the aquifers for subsidence abatement. Hydrologic digital models were developed for theoretical determinations of quantities of water needed, under various well-array plans, for artificial recharge of the Chicot and Evangeline aquifers in order to halt the local subsidence at NASA-JSC. The programs for the models were developed for analysis of three-dimensional ground-water flow. Total injection rates of between 2,000 and 14,000 gallons per minute under three general well-array plans were determined for a range of residual clay pore pressures of 10 to 70 feet of hydraulic head. The space distributions of the resultant hydraulic heads, illustrated for injection rates of 3,600 and 8 ,400 gallons per minute, indicated that, for the same rate, increasing the number and spread of the injection locations reduces the head gradients within NASA-JSC. (Woodard-USGS)

  12. Acoustic flight tests of rotorcraft noise-abatement approaches using local differential GPS guidance

    NASA Technical Reports Server (NTRS)

    Chen, Robert T. N.; Hindson, William S.; Mueller, Arnold W.

    1995-01-01

    This paper presents the test design, instrumentation set-up, data acquisition, and the results of an acoustic flight experiment to study how noise due to blade-vortex interaction (BVI) may be alleviated. The flight experiment was conducted using the NASA/Army Rotorcraft Aircrew Systems Concepts Airborne Laboratory (RASCAL) research helicopter. A Local Differential Global Positioning System (LDGPS) was used for precision navigation and cockpit display guidance. A laser-based rotor state measurement system on board the aircraft was used to measure the main rotor tip-path-plane angle-of-attack. Tests were performed at Crows Landing Airfield in northern California with an array of microphones similar to that used in the standard ICAO/FAA noise certification test. The methodology used in the design of a RASCAL-specific, multi-segment, decelerating approach profile for BVI noise abatement is described, and the flight data pertaining to the flight technical errors and the acoustic data for assessing the noise reduction effectiveness are reported.

  13. Use of the LITEE Lorn Manufacturing Case Study in a Senior Chemical Engineering Unit Operations Laboratory

    ERIC Educational Resources Information Center

    Abraham, Nithin Susan; Abulencia, James Patrick

    2011-01-01

    This study focuses on the effectiveness of incorporating the Laboratory for Innovative Technology and Engineering Education (LITEE) Lorn Manufacturing case into a senior level chemical engineering unit operations course at Manhattan College. The purpose of using the case study is to demonstrate the relevance of ethics to chemical engineering…

  14. An Event-Related Potentials Study of Mental Rotation in Identifying Chemical Structural Formulas

    ERIC Educational Resources Information Center

    Huang, Chin-Fei; Liu, Chia-Ju

    2012-01-01

    The purpose of this study was to investigate how mental rotation strategies affect the identification of chemical structural formulas. This study conducted event-related potentials (ERPs) experiments. In addition to the data collected in the ERPs, a Chemical Structure Conceptual Questionnaire and interviews were also admin-istered for data…

  15. Incorporating transgenerational testing and epigenetic mechanisms into chemical testing and risk assessment: A survey of transgenerational responses in environmental chemical studies

    EPA Science Inventory

    A number of environmental chemicals have been shown to alter markers of epigenetic change. Some published multi-generation rodent studies have identified effects on F2 and greater generations after chemical exposures solely to F0 dams, but were not focused on chemical safety. We ...

  16. Abatement of CF4 by atmospheric-pressure microwave plasma torch

    NASA Astrophysics Data System (ADS)

    Hong, Yong C.; Uhm, Han S.

    2003-08-01

    An atmospheric microwave plasma torch is presented for post-pump destruction of perfluorocompound gases (PFCs), which are used widely in the semiconductor industry and are emitted with nitrogen gas for vacuum pump purges. Discharges of the microwave plasma torch are well suited for abatement of PFC contaminants discharged at a typical flow rate. The abatement was carried out using oxygen or air as additive gases. Analytical results are systematically compared to quadrupole mass spectroscopy and Fourier transform infrared (FTIR) data in the laboratory. Destruction and removal efficiency of more than 99% in FTIR data was achieved for carbon tetrafluoride.

  17. TREATMENT TANK CORROSION STUDIES FOR THE ENHANCED CHEMICAL CLEANING PROCESS

    SciTech Connect

    Wiersma, B.

    2011-08-24

    Radioactive waste is stored in high level waste tanks on the Savannah River Site (SRS). Savannah River Remediation (SRR) is aggressively seeking to close the non-compliant Type I and II waste tanks. The removal of sludge (i.e., metal oxide) heels from the tank is the final stage in the waste removal process. The Enhanced Chemical Cleaning (ECC) process is being developed and investigated by SRR to aid in Savannah River Site (SRS) High-Level Waste (HLW) as an option for sludge heel removal. Corrosion rate data for carbon steel exposed to the ECC treatment tank environment was obtained to evaluate the degree of corrosion that occurs. These tests were also designed to determine the effect of various environmental variables such as temperature, agitation and sludge slurry type on the corrosion behavior of carbon steel. Coupon tests were performed to estimate the corrosion rate during the ECC process, as well as determine any susceptibility to localized corrosion. Electrochemical studies were performed to develop a better understanding of the corrosion mechanism. The tests were performed in 1 wt.% and 2.5 wt.% oxalic acid with HM and PUREX sludge simulants. The following results and conclusions were made based on this testing: (1) In 1 wt.% oxalic acid with a sludge simulant, carbon steel corroded at a rate of less than 25 mpy within the temperature and agitation levels of the test. No susceptibility to localized corrosion was observed. (2) In 2.5 wt.% oxalic acid with a sludge simulant, the carbon steel corrosion rates ranged between 15 and 88 mpy. The most severe corrosion was observed at 75 C in the HM/2.5 wt.% oxalic acid simulant. Pitting and general corrosion increased with the agitation level at this condition. No pitting and lower general corrosion rates were observed with the PUREX/2.5 wt.% oxalic acid simulant. The electrochemical and coupon tests both indicated that carbon steel is more susceptible to localized corrosion in the HM/oxalic acid environment than

  18. Studies of coupled chemical and catalytic coal conversion methods

    SciTech Connect

    Stock, L.M.

    1989-01-01

    A new base catalyzed C-alkylation reaction that employs a mixture of n-butyllithium and potassium t-butoxide in refluxing heptane to produce coal anions that are subsequently treated with n-alkyl halides at 0{degree}C has been developed. Almost quantitative pyridine solubilization was achieved by C-octylation of a Lower Kittanning coal, PSOC 1197. C-Octylation was less successful for the solubilization of bituminous Illinois No. 6 coal, APCSP 3, and subbituminous Wyodak coal, APCSP 2, which gave 35 and 33% soluble material, respectively. Their O-methyl derivatives yielded 43 and 20% soluble material in the same reaction. The observations are in accord with the concept of Ouchi and his associates that higher rank coals, although more aromatic in character, have a lower degree of polymerization than low rank coals. Relatively mild chemical reactions, such as Calkylation, that lead to modest changes in molecular dimensions, can disrupt intermolecular forces and accomplish solubilization.

  19. Development and study of chemical vapor deposited tantalum base alloys

    NASA Technical Reports Server (NTRS)

    Meier, G. H.; Bryant, W. A.

    1976-01-01

    A technique for the chemical vapor deposition of alloys was developed. The process, termed pulsing, involves the periodic injection of reactant gases into a previously-evacuated reaction chamber where they blanket the substrate almost instantaneously. Formation of alternating layers of the alloy components and subsequent homogenization allows the formation of an alloy of uniform composition with the composition being determined by the duration and relative numbers of the various cycles. The technique has been utilized to produce dense alloys of uniform thickness and composition (Ta- 10 wt % W) by depositing alternating layers of Ta and W by the hydrogen reduction of TaCl5 and WCl6. A similar attempt to deposit a Ta - 8 wt % W - 2 wt% Hf alloy was unsuccessful because of the difficulty in reducing HfCl4 at temperatures below those at which gas phase nucleation of Ta and W occurred.

  20. Chemical radiculitis. A clinical, physiological and immunological study.

    PubMed

    Marshall, L L; Trethewie, E R; Curtain, C C

    1977-01-01

    Chemical radiculitis is an inflammatory condition of the nerve root due to the rupture of the annulus fibrosus and dissemination of disk fluid along the nerve root sheath. The inflammatory component of disk fluid is glycoprotein. The inflammation is a reaction to repeated injuries of the spinal column, as for example, in occupational lifting of heavy loads. Rupture of the annulus fibrosus and liberation of disk fluid into the tissues also evokes circulating antibody response and auto immune reaction. A high titer to glycoprotein at 3 weeks after an acute attack of back pain is evidence of the presence of a significant disk lesion. In selected cases immediate relief from pain occurs after administration of cortisone or a suitable cortisone-derivative. Prolonged rest may be contraindicated because of the risk of formation of radicular adhesions. PMID:608297

  1. Groundwater hydrology study of the Ames Chemical Disposal Site

    SciTech Connect

    Stickel, T.

    1996-05-09

    The Ames Laboratory Chemical Disposal Site is located in northwestern Ames, Iowa west of Squaw Creek. From 1957 to 1966, Ames Laboratory conducted research to develop processes to separate uranium and thorium from nuclear power fuel and to separate yttrium from neutron shielding sources. The wastes from these processes, which contained both hazardous and radiological components, were placed into nine burial pits. Metal drums, plywood boxes, and steel pails were used to store the wastes. Uranium was also burned on the ground surface of the site. Monitoring wells were placed around the waste burial pits. Groundwater testing in 1993 revealed elevated levels of Uranium 234, Uranium 238, beta and alpha radiation. The north side of the burial pit had elevated levels of volatile organic compounds. Samples in the East Ravine showed no volatile organics; however, they did contain elevated levels of radionuclides. These analytical results seem to indicate that the groundwater from the burial pit is flowing down hill and causing contamination in the East Ravine. Although there are many avenues for the contamination to spread, the focus of this project is to understand the hydrogeology of the East Ravine and to determine the path of groundwater flow down the East Ravine. The groundwater flow data along with other existing information will be used to assess the threat of chemical migration down the East Ravine and eventually off-site. The primary objectives of the project were as follows: define the geology of the East Ravine; conduct slug tests to determine the hydraulic conductivity of both oxidized and unoxidized till; develop a three-dimensional mathematical model using ModIME and MODFLOW to simulate groundwater flow in the East Ravine.

  2. Health and environmental outcomes of traditional and modified practices for abatement of residential lead-based paint.

    PubMed Central

    Farfel, M R; Chisolm, J J

    1990-01-01

    We evaluated traditional and modified practices for abating lead-based paint in homes of children with blood-lead concentrations (PbB) greater than 1.4 mumol/L (greater than 29 micrograms/dl). Traditional abatement resulted in acute increases in: 1) lead contaminated house dust (generally 3 to 6-fold over pre-abatement levels, but at abated sites typically 10 to 100-fold); and 2) the PbBs of nearly half of the occupant children. Modified practices represented modest short-term improvement compared to traditional practices but were also inadequate. By six months, it was clear that neither form of abatement resulted in long-term reductions of PbB or house dust lead levels, leaving children at continued risk of excessive exposure to lead and permanent adverse neurobehavioral effects. Windows were found to be high sources of lead contaminated house dust. Recommendations are made for improved abatement practices including more complete abatement of window units and more effective clean-up to remove lead-bearing dust. Thirteen million US children live in lead-painted dwellings. Research is needed to identify abatement strategies that will be practical and well suited to the current understanding of low-level lead toxicity. PMID:2136329

  3. Health and environmental outcomes of traditional and modified practices for abatement of residential lead-based paint

    SciTech Connect

    Farfel, M.R.; Chisolm, J.J. Jr. )

    1990-10-01

    We evaluated traditional and modified practices for abating lead-based paint in homes of children with blood-lead concentrations (PbB) greater than 1.4 mumol/L (greater than 29 micrograms/dl). Traditional abatement resulted in acute increases in: (1) lead contaminated house dust (generally 3 to 6-fold over pre-abatement levels, but at abated sites typically 10 to 100-fold); and (2) the PbBs of nearly half of the occupant children. Modified practices represented modest short-term improvement compared to traditional practices but were also inadequate. By six months, it was clear that neither form of abatement resulted in long-term reductions of PbB or house dust lead levels, leaving children at continued risk of excessive exposure to lead and permanent adverse neurobehavioral effects. Windows were found to be high sources of lead contaminated house dust. Recommendations are made for improved abatement practices including more complete abatement of window units and more effective clean-up to remove lead-bearing dust. Thirteen million US children live in lead-painted dwellings. Research is needed to identify abatement strategies that will be practical and well suited to the current understanding of low-level lead toxicity.

  4. Crystal chemical and quantum chemical studies of Ba(Sr)-Nb oxide compounds

    NASA Technical Reports Server (NTRS)

    Zubkov, V. G.; Turzhevsky, S. A.; Pereliaev, V. A.; Liechtenstein, A. I.; Gubanov, V. A.

    1990-01-01

    The information available on the BaO(SrO)-NbO-NbO2 system with the niobium atom in the lower oxidation degree is very limited. Very few compounds have been found previously in this system. They are BaNbO3, SrxNbO3(0,7=x=1), Ba2Nb2O9, SrNb8O14; and some suggestions on the BaNb8O14 existence have been made also. At the same time Nb-based oxide compounds could be quite interesting in the search of new noncopper high T(sub c) superconductors Researchers studied Ba(Sr) NbxO2x-2 and Ba2(Sr2)-NbxO2x-1 compositions in the phase diagram of BaO(SrO)-NbO-NbO2 system. The synthesis of the materials was carried out in vacuum at the temperatures of 1000 to 1500 C. Barium carbonate and niobium pentoxide were used as initial components. X-ray analysis was carried out.

  5. GUIDE FOR CONDUCTING TREATABILITY STUDIES UNDER CERCLA: CHEMICAL DEHALOGENATION (QUICK REFERENCE FACT SHEET)

    EPA Science Inventory

    Systematically conducted, well-documented treatability studies are an important component of remedy evaluation and selection under the Superfund program. his manual focuses on chemical dehalogenation treatability studies conducted in support of remedy selection that is conducted ...

  6. [Study on Chemical Kinetic Effect of Dielectric Barrier Discharge Plasma].

    PubMed

    Zrang, Peng; Hong, Yan-ji; Shen, Shuang-yan; Ding, Xiao-yu; Ma, Di

    2015-03-01

    To reveal the mechanism of plasma (assisted the ignition process of methane/air further, schematic of dielectric barrier discharge plasma system with atmospheric air was designed and set up, the emission spectrum of dielectric barrier discharge plasma with atmospheric air was measured, and the active particles produced by the interaction of dielectric barrier discharge plasma with atmospheric air were analyzed with the spectrum technology, the ignition model and calculation methods of sensitivity analysis and reaction path analysis were given, effects of NO and O3 on the ignition delay time were simulated, and the chemical kinetics mechanism of NO and O3 assisted ignition was revealed via sensitivity analysis and reaction path analysis. The results show that main excited particles of N2 and O3 are generated via effect of plasma on the atmospheric air, which are converted into active particles of NO(ξ) and O3 in the end, the life of which are longer than any other active particles, effects of plasma on the ignition is simplified as effects of NO(ξ) and O3 on the ignition; NO and O3 could reduce the ignition delay time significantly, but the amplitude decrease with increase of the initial temperature, this is because the rate of ignition is decided by the oxidation rate of CH3, the oxidized pathway of CH3 is R155 and R156 for auto-ignition and their rates are slower when temperature is low, so the ignition delay time of methane/air is longer; NO could reduce the ignition delay time significantly because of the oxidized pathway of CH3 is changed to R327 CH3O2 + NO = CH3O + NO2, R328 CH3 + NO2 = CH3O + NO for NO(ξ) (assisted ignition process from R155 and R156 for auto-ignition; and the chemical kinetic effect is the dominating factor of O3 on the ignition and which change the reaction path. PMID:26117883

  7. Study of Aerosol Chemical Composition Based on Aerosol Optical Properties

    NASA Astrophysics Data System (ADS)

    Berry, Austin; Aryal, Rudra

    2015-03-01

    We investigated the variation of aerosol absorption optical properties obtained from the CIMEL Sun-Photometer measurements over three years (2012-2014) at three AERONET sites GSFC; MD Science_Center and Tudor Hill, Bermuda. These sites were chosen based on the availability of data and locations that can receive different types of aerosols from land and ocean. These absorption properties, mainly the aerosol absorption angstrom exponent, were analyzed to examine the corresponding aerosol chemical composition. We observed that the retrieved absorption angstrom exponents over the two sites, GSFC and MD Science Center, are near 1 (the theoretical value for black carbon) and with low single scattering albedo values during summer seasons indicating presence of black carbon. Strong variability of aerosol absorption properties were observed over Tudor Hill and will be analyzed based on the air mass embedded from ocean side and land side. We will also present the seasonal variability of these properties based on long-range air mass sources at these three sites. Brent Holben, NASA GSFC, AERONET, Jon Rodriguez.

  8. Quantum chemical study of the autoxidation of ascorbate.

    PubMed

    Herrmann, Nils; Heinz, Norah; Dolg, Michael; Cao, Xiaoyan

    2016-07-01

    Reactions involved in the autoxidation of ascorbate have been investigated with quantum chemical first-principles and ab initio methods. Reaction energies and Gibbs energies of the reactions were calculated at the density functional theory level applying the gradient-corrected BP86 and the hybrid B3LYP functionals together with def2-TZVP basis sets. Results of single-point CC2, CCSD, and CCSD(T) calculations were used for calibration of the density functional theory data and show excellent agreement with the B3LYP values. Based on the Gibbs energy ascorbic acid AscH2 is found to be the energetically lowest species in aqueous solution, whereas the monoanion ascorbate AscH - is the most abundant one near pH = 7. Asc 2- was found to be the preferred reducing agent for autoxidation and oxidation processes. The results also support a metal-catalyzed synthesis of the reactive oxygen species H2 O2 according to a redox cycling mechanism proposed in literature. © 2016 Wiley Periodicals, Inc. PMID:27316823

  9. Clinical Chemical Studies in Aleutian Disease of Mink

    PubMed Central

    Gershbein, Leon L.; Spencer, Kathryn L.

    1964-01-01

    Clinical chemical determinations were carried out on blood removed by cardiac puncture from 49 mink affected with Aleutian disease and 25 normal animals and the respective differences tested for statistical significance. Blood urea nitrogen, serum total protein and globulin, thymol turbidity, glutamic oxalacetic and glutamic pyruvic transaminases and amylase were definitely elevated in the affected animals whereas serum calcium, albumin and A/G ratio were depressed. No statistically significant difference was apparent between the two groups in the comparison of inorganic phosphorus, alkaline and acid phosphatases, bilirubin, total cholesterol and esters, cephalin-cholesterol flocculation (3+ in each case), sodium, potassium, chloride, CO2-combining power, leucine aminopeptidase and lactic dehydrogenase (means: over 2,000 u./ml.). For both the control and affected mink, the distribution of serum lactic dehydrogenase isozymes resembled that of human homologous serum hepatitis. Electrophoresis of serum proteins confirmed earlier findings of hypergammaglobulinemia in the diseased animals but a fast-moving or pre-albumin component, averaging 4% of the total protein, occurred in both the diseased and normal mink. ImagesFigure 1. PMID:17649484

  10. Studies on chemical kinetics of positronium complex formation

    NASA Astrophysics Data System (ADS)

    Du, Youming; Zhang, Tianbao; Cao, Chun; Chen, Yun-Ti; Liang, Jiachang

    1993-09-01

    The complex formation between ortho-positronium and N-( p-substituted-phenyl) glycine ( p-RPhG, G=NHCH 2COOH; R=NO 2, Cl, H, CH 3, CH 3O) or N-( m-substituted-phenyl) glycine ( m-RPhG, R=NO 2, Cl) in solutions of 30% (v/v) ethanol—water and 20% (v/v) dioxane—water is discussed. The application of a BaF 2 scintillation counter to a positron annihilation lifetime spectrometer is described. By means of this new type of spectrometer, the complex formation reaction rate constants of ortho-positronium with the glycine derivatives in solutions are determined. The results indicate that the rate constants mainly depend on the conjugation effect at the benzene ring, the induction effects of the substitutes on the phenyl and solvents. There exists a linear free-energy relationship between rate constants and the basicities of N-substituted phenyl glycines in ortho-positronium—glycine complex formation. It means that the transient complex formation of ortho-positronium with molecules is like a general chemical reaction and obeys classical rules.

  11. Photovoltaic Study of Chemically Derived Titanium-Doped Polythiophene Composites

    NASA Astrophysics Data System (ADS)

    Takpire, S. R.; Waghuley, S. A.

    2015-08-01

    In the present work, titanium (Ti)-doped polythiophene (PTh) was synthesized by a chemical route using titanium chloride as oxidant. As-synthesized composites were further used for fabrication of photovoltaic (PV) cells with indium tin oxide/Ti-doped PTh/aluminum architecture. Structural, morphological, and optical analyses of as-synthesized composites were carried out through x-ray diffraction (XRD) analysis, Fourier-transform infrared (FTIR) spectroscopy, field-emission scanning electron microscopy (FE-SEM), ultraviolet-visible (UV-Vis) spectroscopy, and photoluminescence (PL) measurements. A broad peak was found in the PL spectra of the composites at around 480 nm, indicating high charge generation efficiency. Different PV parameters of the fabricated PV cells were measured at room temperature under incandescent light of 100 W/m2. The optimized PV cell exhibited short-circuit current ( I sc) and open-circuit voltage ( V oc) on the order of 176 μA and 0.595 V, respectively. The values of I sc and V oc were used to compute the fill factor, which was found to be 0.521. The corresponding power conversion efficiency associated with the optimized cell was found to be 2.41%.

  12. Abatement of morphine-induced slowing in gastrointestinal transit by Dai-kenchu-to, a traditional Japanese herbal medicine.

    PubMed

    Nakamura, Tomonori; Sakai, Akiko; Isogami, Issei; Noda, Kazuhiro; Ueno, Koichi; Yano, Shingo

    2002-02-01

    As a way of alleviating severe constipation in cancer patients taking morphine to relieve pain, effects of Dai-kenchu-to (DKT), a traditional Japanese herbal medicine (Kampo medicine), on gastrointestinal transit in mice or on the isolated guinea pig ileum were studied in special reference to morphine. Without altering the anti-nociceptive effect of morphine, DKT was significantly effective against morphine-induced disorder of gastrointestinal transit in mice as assessed by the charcoal meal test for the intestine and measurement of transit time for the colon tract. The results of in vitro studies with guinea pig ileum suggest that abatement of morphine-induced disorder of transit by DKT is caused by both moderate contraction of morphine-treated longitudinal muscle and relaxation of morphine-induced tonic contraction of circular muscle. PMID:11928724

  13. PM 2.5 CHEMICAL SPECIATION SAMPLER EVALUATION FIELD PROGRAM: RESULTS FROM THE FOUR CITY STUDY

    EPA Science Inventory

    The objective of this sampler intercomparison field study is to determine the performance characteristics for the collection of the chemical components of PM2.5 by the chemical speciation monitors developed for the national network relative to each other, to the Federal Referen...

  14. UPTAKE, METABOLISM, AND DISPOSITION OF XENOBIOTIC CHEMICALS IN FISH. WISCONSIN POWER PLANT IMPACT STUDY

    EPA Science Inventory

    The effects and fate in fish of a number of chemicals, including hydrocarbons and chlorinated hydrocarbons, have been examined. The interactions between these chemicals and fish have been studied using several approaches. The uptake an elimination of 14C-labeled napthalene, 2-met...

  15. [Advances in studies on chemical constituents and biological activities of Desmodium species].

    PubMed

    Liu, Chao; Wu, Ying; Zhang, Qian-Jun; Kang, Wen-Yi; Zhang, Long; Zhou, Qing-Di

    2013-12-01

    The chemical constituents isolated from Desmodium species (Leguminosae) included terpenoids, flavonoids, steroids, alkaloids compounds. Modem pharmacological studies have showed that the Desmodium species have antioxidant, antibacterial, anti-inflammatory, hepatoprotective, diuretic, antipyretic, analgesic and choleretic activity. This article mainly has reviewed the research advances of chemical constituents and biological activities of Desmodium species since 2003. PMID:24791478

  16. Wave Tank Studies On Formation And Transport Of OMA From The Chemically Dispersed Oil

    EPA Science Inventory

    The interaction of chemical dispersants and suspended sediments with crude oil influences the fate and transport of oil spills in coastal waters. A wave tank study was conducted to investigate the effects of chemical dispersants and mineral fines on dispersion of oil, formation ...

  17. PLANT EXPOSURE CHAMBERS FOR STUDY OF TOXIC CHEMICAL-PLANT INTERACTIONS (JOURNAL VERSION)

    EPA Science Inventory

    Chambers for the study of plant uptake and phytotoxicity of toxic, radio-labeled chemicals are described. The chambers are designed to meet the criteria of continuously stirred tank reactors while providing containment for toxic chemical. They are computer managed and operated wi...

  18. 75 FR 29754 - Claims of Confidentiality of Certain Chemical Identities Contained in Health and Safety Studies...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-27

    ..., 2010 (75 FR 3462) (FRL-8807-9), EPA announced that `` here a health and safety study submitted under... chemical substances of unknown or variable composition, complex reaction products and biological materials... AGENCY Claims of Confidentiality of Certain Chemical Identities Contained in Health and Safety...

  19. In-Situ Chemical Reduction and Oxidation of VOCs in Groundwater: Groundwater Treatability Studies

    NASA Technical Reports Server (NTRS)

    Keith, Amy; Glasgow, Jason; McCaleh, Rececca C. (Technical Monitor)

    2001-01-01

    This paper presents NASA Marshall Space Flight Center's treatability studies for volatile organic compounds in groundwater. In-Situ groundwater treatment technologies include: 1) Chemical Reduction(Ferox); 2) Chemical Oxidation (Fenton Reagents, Permanganate, and Persulfate); and 3) Thermal (Dynamic Underground Stripping, Six-Phase Heating). This paper is presented in viewgraph form.

  20. Single-collision studies of energy transfer and chemical reaction

    SciTech Connect

    Valentini, J.J.

    1993-12-01

    The research focus in this group is state-to-state dynamics of reaction and energy transfer in collisions of free radicals such as H, OH, and CH{sub 3} with H{sub 2}, alkanes, alcohols and other hydrogen-containing molecules. The motivation for the work is the desire to provide a detailed understanding of the chemical dynamics of prototype reactions that are important in the production and utilization of energy sources, most importantly in combustion. The work is primarily experimental, but with an important and growing theoretical/computational component. The focus of this research program is now on reactions in which at least one of the reactants and one of the products is polyatomic. The objective is to determine how the high dimensionality of the reactants and products differentiates such reactions from atom + diatom reactions of the same kinematics and energetics. The experiments use highly time-resolved laser spectroscopic methods to prepare reactant states and analyze the states of the products on a single-collision time scale. The primary spectroscopic tool for product state analysis is coherent anti-Stokes Raman scattering (CARS) spectroscopy. CARS is used because of its generality and because the extraction of quantum state populations from CARS spectra is straightforward. The combination of the generality and easy analysis of CARS makes possible absolute cross section measurements (both state-to-state and total), a particularly valuable capability for characterizing reactive and inelastic collisions. Reactant free radicals are produced by laser photolysis of appropriate precursors. For reactant vibrational excitation stimulated Raman techniques are being developed and implemented.

  1. Raman spectroscopic studies of chemical speciation in calcium chloride melts

    SciTech Connect

    Windisch, Charles F.; Lavender, Curt A.

    2005-02-01

    Raman spectroscopy was applied to CaCl2 melts at 900 degrees C under both non-electrolyzed and electrolyzed conditions. The later used titania cathodes supplied by TIMET, Inc. and graphite anodes. Use of pulse-gating to collect the Raman spectra successfully eliminated any interference from black-body radiation and other stray light. The spectrum of molten CaCl2 exhibited no distinct, resolvable bands that could be correlated with a calcium chloride complex similar to MgCl42- in MgCl2 melts. Rather, the low frequency region of the spectrum was dominated by a broad “tail” arising from collective oscillations of both charge and mass in the molten salt “network.” Additions of both CaO and Ca at concentrations of a percent or two resulted in no new features in the spectra. Addition of CO2, both chemically and via electrolysis at concentrations dictated by stability and solubility at 900 degrees C and 1 bar pressure, also produced no new bands that could be correlated with either dissolved CO2 or the carbonate ion. These results indicated that Raman spectroscopy, at least under the conditions evaluated in the research, was not well suited for following the reactions and coordination chemistry of calcium ions, nor species such as dissolved metallic Ca and CO2 that are suspected to impact current efficiency in titanium electrolysis cells using molten CaCl2. Raman spectra of TIMET titania electrodes were successfully obtained as a function of temperature up to 900 degrees C, both in air and in-situ in CaCl2 melts. However, spectra of these electrodes could only be obtained when the material was in the unreduced state. When reduced, either with hydrogen or within an electrolysis cell, the resulting electrodes exhibited no measurable Raman bands under the conditions used in this work.

  2. A Critique of the Public Education Approach to Industrial Pollution Abatement.

    ERIC Educational Resources Information Center

    Hammer, Eliot R.

    1973-01-01

    Public education cannot be considered an efficient alternative to industrial pollution abatement. The public education alternative stresses that an informed non-industrial public will, out of civic responsibility, bring about sufficient social pressure on the industrial sector to end pollution. However, evidence suggests that the mere presence of…

  3. 30 CFR 75.401 - Abatement of dust; water or water with a wetting agent.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... wetting agent. 75.401 Section 75.401 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Combustible Materials and Rock Dusting § 75.401 Abatement of dust; water or water with a wetting agent....

  4. 29 CFR 1903.14a - Petitions for modification of abatement date.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 5 2010-07-01 2010-07-01 false Petitions for modification of abatement date. 1903.14a Section 1903.14a Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR INSPECTIONS, CITATIONS AND PROPOSED PENALTIES § 1903.14a Petitions...

  5. Biological inhibitor abatement and ethanol fermentation of sugars from dilute acid-pretreated rice hulls

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fermentation inhibitors arise from lignin, hemicellulose, and degraded sugar during pretreatment of lignocellulosic biomass. Use of a microbe has been explored for abatement of pretreated biomass in which fermentation inhibitors, if left untreated, can complicate microbial conversion of biomass to f...

  6. THE SCIENCE OF REMEDIATION, ABATEMENT, AND DECOMMISSIONING OF CATASTROPHIC (AND LESSER) EVENTS

    EPA Science Inventory

    This is a brief overview of some of the activities commonly involved in remediation, abatement, and decommissioning of areas affected by significant events whether natural or man-made. Some examples from the EPA's post-Katrina and anthrax responses are used to demonstrate the sc...

  7. SCANNING ELECTRON MICROSCOPY/X-RAY FLUORESCENCE CHARACTERIZATION OF POST-ABATEMENT DUST

    EPA Science Inventory

    Scanning electron microscopy (SEM) and laboratory X-ray fluorescence (XRF) were used to characterize post-abatement dust collected with a HEPA filtered vacuum. hree size fractions of resuspended dust (0-30 pm, 2.5-15 pm, and <2.5 pm) were collected on teflon filters and analyzed ...

  8. Award for Distinguished Professional Contributions to Applied Research: Luciano L'Abate

    ERIC Educational Resources Information Center

    American Psychologist, 2009

    2009-01-01

    Luciano L'Abate, recipient of the Award for Distinguished Professional Contributions to Applied Research, contributed to applied research through the introduction of the laboratory method in clinical psychology assessment and intervention, leading to the development of the first automated playroom, linking play therapy with research in child…

  9. 29 CFR 4208.5 - Withdrawal liability payments during pendency of abatement determination.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... making scheduled withdrawal liability payments in the second year for those withdrawals, provide a bond... second consecutive plan year. An employer that applies for abatement and neither provides a bond/escrow...) Plan amendments concerning bond/escrow. A plan may, by amendment, adopt rules decreasing the amount...

  10. 29 CFR 4208.5 - Withdrawal liability payments during pendency of abatement determination.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... making scheduled withdrawal liability payments in the second year for those withdrawals, provide a bond... second consecutive plan year. An employer that applies for abatement and neither provides a bond/escrow...) Plan amendments concerning bond/escrow. A plan may, by amendment, adopt rules decreasing the amount...

  11. Perverse effects of carbon markets on HFC-23 and SF6 abatement projects in Russia

    NASA Astrophysics Data System (ADS)

    Schneider, Lambert; Kollmuss, Anja

    2015-12-01

    Carbon markets are considered a key policy tool to achieve cost-effective climate mitigation. Project-based carbon market mechanisms allow private sector entities to earn tradable emissions reduction credits from mitigation projects. The environmental integrity of project-based mechanisms has been subject to controversial debate and extensive research, in particular for projects abating industrial waste gases with a high global warming potential (GWP). For such projects, revenues from credits can significantly exceed abatement costs, creating perverse incentives to increase production or generation of waste gases as a means to increase credit revenues from waste gas abatement. Here we show that all projects abating HFC-23 and SF6 under the Kyoto Protocol’s Joint Implementation mechanism in Russia increased waste gas generation to unprecedented levels once they could generate credits from producing more waste gas. Our results suggest that perverse incentives can substantially undermine the environmental integrity of project-based mechanisms and that adequate regulatory oversight is crucial. Our findings are critical for mechanisms in both national jurisdictions and under international agreements.

  12. ACHIEVING A TRANSMISSION ELECTRON MICROSCOPY CLEARANCE CRITERION AT ASBESTOS ABATEMENT SITES IN NEW JERSEY

    EPA Science Inventory

    Representatives of the New Jersey Department of Health's Asbestos Control Service conducted final clearance evaluations at 79 schools where asbestos removal took place during the Summer of 1987. The evaluations entailed a thorough visual inspection of each abatement area by an ex...

  13. ECOLOGICAL RESPONSES TO POLLUTION ABATEMENT: A FRAMEWORK FOR MEASUREMENT AND ASSESSMENT FOR COASTAL ECOSYSTEMS

    EPA Science Inventory

    Ecological Responses to Pollution Abatement: A Framework for Measurement and Assessment for Coastal Ecosystems (Abstract). To be presented at the 16th Biennial Conference of the Estuarine Research Foundation, ERF 2001: An Estuarine Odyssey, 4-8 November 2001, St. Pete Beach, FL. ...

  14. Guidelines for Assessment and Abatement of Asbestos-Containing Materials in Buildings.

    ERIC Educational Resources Information Center

    Pielert, James H.; Mathey, Robert G.

    This report presents guidelines, based on available information, for the assessment and abatement of asbestos-containing materials in buildings. Section 1 provides background information on the history and use of asbestos-containing products in buildings, the characteristics of asbestos fibers, products and materials containing asbestos, and…

  15. 29 CFR 1903.14a - Petitions for modification of abatement date.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 5 2011-07-01 2011-07-01 false Petitions for modification of abatement date. 1903.14a Section 1903.14a Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR INSPECTIONS, CITATIONS AND PROPOSED PENALTIES § 1903.14a Petitions...

  16. Impact of the implementation of PM abatement technology on the ambient air levels of metals in a highly industrialised area

    NASA Astrophysics Data System (ADS)

    Querol, X.; Minguillón, M. C.; Alastuey, A.; Monfort, E.; Mantilla, E.; Sanz, M. J.; Sanz, F.; Roig, A.; Renau, A.; Felis, C.; Miró, J. V.; Artíñano, B.

    Data on the spatial and time (2002-2005) variation of levels of trace elements and the source attribution of these elements in the ceramic cluster of Castelló (Eastern Spain) are presented and discussed. Earlier studies concluded that metal levels in PM 10 were one of the most critical parameters for attaining the EU legal requirements of the air quality standards. Levels of Li, Sc, Co, Zn, As, Se, Rb, Zr, Cd, Cs, Ce, Tl and Pb were higher than the usual range of concentration in urban areas of Spain, and some of them exceeded the concentration ranges obtained for other industrial sites in Spain. Of these elements, Zr, Zn, Pb and As (and probably Tl) may be considered as tracers of the ceramic emissions from the study area. A downward trend was observed for most of them, simultaneously, with the progressive implementation of the emission abatement techniques, especially those applied to the PM abatement of the manufacture of glaze components and the avoidance of the use of specific raw materials with high contents of impurities. At the end of the study period, the elements for which the EU sets limit or target values met the established requirements for 2013 (2005 for Pb), whereas, at the beginning of the study some elements exceeded the 2013 target values. Furthermore, a detailed discussion on the interpretation of peak concentration events and source attribution for a number of trace elements is presented. Five different sources were identified: mineral emissions (from clay use and handling), industry (mainly glaze production and use), road traffic, sea spray and the regional background influenced by a fuel oil-power plant and a petrochemical plant.

  17. Radiation and chemical studies of carcinogens, polycyclic aromatic hydrocarbons

    SciTech Connect

    Chen, Chiachieh.

    1989-01-01

    Radiation and polycyclic aromatic hydrocarbons (PAH's) are environmental pollutants. 3MC effectively neutralized the lethality of C3H mouse 10T1/2 cells resulting from B(a)P or DMBA. PAH binding to macromolecules increased linearly with exposure, but DNA-adducts saturated with exposure. 3MC or {alpha}NF appreciably reduced the formation of DNA adducts due to B(a)P or DMBA. The reductions in DNA-adduct formation did not result from a reduction in the induction of AHH. By using DNA adducts as chemical dose, and plotting the DMBA survival curve as a function of DMBA-DNA adducts, the curve was an exponential curve. A similar application with B(a)P-DNA adduct showed the survival curve as a shoulder followed by an exponential region. When 10T1/2 cells were treated with X-radiation and a PAH, the nontoxic compounds and B(a)P did not show any significant effect on X-ray survival curve. However, the damage due to DMBA was found to be additive to X-ray damage. The latter property of DMBA was lost when cells were cotreated with 3MC and DMBA presumably because damage to DNA due to DMBA alone was suppressed. Thus, the combined action is complex. DMBA produced damage in 10T1/2 cells that added to radiation damage. Although a nontoxic PAH could neutralize the effect of a toxic PAH, the former were not able to mitigate the lethal effects of radiation. Operationally, the latter results suggested that a nontoxic PAH could cancel out the effect of a toxic one because it inhibited the formation of the DNA damage with which radiation damage could interact rather than because the nontoxic PAH removed the radiation damage with which the PAH could interact. It showed that at least 4 hours were required for DMBA to affect the sublethal radiation damage repair, a period long enough for a large fraction of the latter damage to have been lost.

  18. Use of multi-transition-metal-ion-exchanged zeolite 13X catalysts in methane emissions abatement

    SciTech Connect

    Hui, K.S.; Chao, C.Y.H.; Kwong, C.W.; Wan, M.P.

    2008-04-15

    Methane is a potent greenhouse gas. It has a global warming potential (GWP) 23 times greater than carbon dioxide. Reducing methane emissions would lead to substantial economic and environmental benefits. This study investigated the performance of multi-transition-metal-(Cu, Cr, Ni, and Co)-ion-exchanged zeolite 13X catalysts in methane emissions abatement. The catalytic activity in methane combustion using multi-ion-exchanged catalysts was studied with different parameters including the molar percentage of metal loading, the space velocity, and the inlet methane concentration under atmospheric pressure and at a relatively low reaction temperature of 500 C. The performance of the catalysts was determined in terms of the apparent activation energy, the number of active sites of the catalyst, and the BET surface area of the catalyst. This study showed that multi-ion-exchanged catalysts outperformed single-ion-exchanged and acidified 13X catalysts and that lengthening the residence time led to a higher methane conversion percentage. The enhanced catalytic activity in the multi-ion-exchanged catalysts was attributed to the presence of exchanged transition ions instead of acid sites in the catalyst. The catalytic activity of the catalysts was influenced by the metal loading amount, which played an important role in affecting the apparent activation energy for methane combustion, the active sites, and the BET surface area of the catalyst. Increasing the amount of metal loading in the catalyst decreased the apparent activation energy for methane combustion and also the BET surface area of the catalyst. An optimized metal loading amount at which the highest catalytic activity was observed due to the combined effects of the various factors was determined. (author)

  19. Undisclosed chemicals--implications for risk assessment: a case study from the mining industry.

    PubMed

    Singh, Khareen; Oates, Christopher; Plant, Jane; Voulvoulis, Nikolaos

    2014-07-01

    Many of the chemicals used in industry can be hazardous to human health and the environment, and some formulations can have undisclosed ingredients and hazards, increasing the uncertainty of the risks posed by their use. The need for a better understanding of the extent of undisclosed information in chemicals arose from collecting data on the hazards and exposures of chemicals used in typical mining operations (copper, platinum and coal). Four main categories of undisclosed chemicals were defined (incomplete disclosure; chemicals with unspecific identities; relative quantities of ingredients not stated; and trade secret ingredients) by reviewing material safety data sheet (MSDS) omissions in previous studies. A significant number of chemicals (20% of 957 different chemicals) across the three sites had a range of undisclosed information, with majority of the chemicals (39%) having unspecific identities. The majority of undisclosed information was found in commercially available motor oils followed by cleaning products and mechanical maintenance products, as opposed to reagents critical to the main mining processes. All three types of chemicals had trade secrets, unspecific chemical identities and incomplete disclosures. These types of undisclosed information pose a hindrance to a full understanding of the hazards, which is made worse when combined with additional MSDS omissions such as acute toxicity endpoints (LD50) and/or acute aquatic toxicity endpoints (LC50), as well as inadequate hazard classifications of ingredients. The communication of the hazard information in the MSDSs varied according to the chemical type, the manufacturer and the regulations governing the MSDSs. Undisclosed information can undermine occupational health protection, compromise the safety of workers in industry, hinder risk assessment procedures and cause uncertainty about future health. It comes down to the duty of care that industries have towards their employees. With a wide range of

  20. The effect of chemical modification on the physico-chemical characteristics of halloysite: FTIR, XRF, and XRD studies

    NASA Astrophysics Data System (ADS)

    Szczepanik, Beata; Słomkiewicz, Piotr; Garnuszek, Magdalena; Czech, Kamil; Banaś, Dariusz; Kubala-Kukuś, Aldona; Stabrawa, Ilona

    2015-03-01

    The effect of chemical modification of halloysite from a Polish strip mine "Dunino" on the chemical composition and structure of this clay mineral was studied using infrared spectroscopy (ATR FT-IR), wavelength dispersive X-ray fluorescence (WDXRF), and X-ray powder diffraction (XRPD) methods. The results obtained by the WDXRF technique confirm that the content of silica and alumina was the highest for bleached halloysite samples and the lowest for acid-treated halloysite. A higher content of Fe2O3 in comparison to halloysite samples coming from other countries was observed for raw halloysite samples. XRPD diffraction pattern obtained for raw halloysite confirmed the presence of halloysite, kaolinite, hematite, and calcite minerals in the sample. Bleaching the halloysite removes (or significantly reduces) the content of other minerals present in the raw halloysite. The FT-IR spectra of the studied halloysite samples show in the 3700-3600 cm-1 region well-defined hydroxyl stretching bands characteristic for the kaolin-group minerals and bands associated with the vibrations of the aluminium-silicon skeleton in the 1400-1000 cm-1 region. Modifying halloysite with 4-chloro-aniline causes successive incorporation of amine into the BH sample.

  1. Synthesis and analysis in studies of chemical evolution

    NASA Technical Reports Server (NTRS)

    Ponnamperuma, C.; Hobish, M. K.; Kobayashi, K.; Hua, L. L.; Senaratne, N.

    1986-01-01

    Studies of the various processes that may have given rise to life on the Earth have demonstrated the appropriateness of an approach that makes use of analysis and synthesis. Analysis of extraterrestrial samples in the form of meteorites has demonstrated the presence of several precursors of biomolecules, most notably a full suite of nucleic acid bases and nucleotides of biological significance. These species were determined after exhaustive extraction of the sample and subsequent analysis using HPLC, GC, MS, and GC-MS. Procedural blanks indicate that these molecules are likely not the result of contamination during the extraction and analysis process. Similar species were found as products of spark discharge experiments in atmospheres thought to mimic primitive Earth conditions. These results indicate that the basic chemistry underlying these syntheses is common, and that life may not be unique to the Earth. Studies underway in the laboratory make use of proton nuclear magnetic resonance spectroscopy as a probe to assess associations between selected amino acids and any of several nucleotides comprising their genetic code and genetic anticode sequences. These studies demonstrate a clear selectivity by the anticode sequences, thus confirming the hydrophobicity studies performed by Lacey et al. These studies further support the contention that life is likely a natural result of the physics and chemistry of the universe.

  2. Study of Chemical Carcinogens by Positron Annihilation Lifetime Spectroscopy

    NASA Astrophysics Data System (ADS)

    Pivtsaev, A. A.; Razov, V. I.; Karasev, A. O.

    2013-11-01

    We have used positron annihilation lifetime spectroscopy to study the carcinogens C21H20BrN3, C4H7Cl2O4P, CCl4, CHCl3, AlF3, C8H12N4O, C6H4Cl2 and the non-carcinogens H2O, AlCl3, CH2Cl2, C2H6OS. We have established a correlation between the annihilation characteristics of the studied compounds and their degree of carcinogenicity.

  3. Oak Ridge Y-12 Plant Biological Monitoring and Abatement Program Plan

    SciTech Connect

    Adams, S.M.; Brandt, C.C.; Christensen, S.W.; Greeley, M.S.JR.; Hill, W.R.; Peterson, M.J.; Ryon, M.G.; Smith, J.G.; Southworth, G.R.; Stewart, A.J.

    2000-09-01

    The revised Biological Monitoring and Abatement Program (BMAP) for East Fork Poplar Creek (EFPC) at the Oak Ridge Y-12 Plant, as described, will be conducted as required by the National Pollutant Discharge Elimination System permit issued for the Y-12 Plant on April 28, 1995 and became effective July 1, 1995. The basic approach to biological monitoring used in this program was developed by the staff in the Environmental Science Division (ESD) at the Oak Ridge National Laboratory (ORNL) at the request of the Y-12 Plant. The revision to the BMAP plan is based on results of biological monitoring conducted during the period of 1985 to present. Details of the specific procedures used in the current routine monitoring program are provided; experimental designs for future studies are described in less detail. The overall strategy used in developing this plan was, and continues to be, to use the results obtained from each task to define the scope of future monitoring efforts. Such efforts may require more intensive sampling than initially proposed in some areas (e.g., additional bioaccumulation monitoring if results indicate unexpectedly high PCBs or Hg) or a reduction in sampling intensity in others (e.g., reduction in the number of sampling sites when no impact is still observed). The program scope will be re-evaluated annually. By using the results of previous monitoring efforts to define the current program and to guide us in the development of future studies, an effective integrated monitoring program has been developed to assess the impacts of Y-12 Plant operations (past and present) on the biota of EFPC and to document the ecological effects of remedial actions.

  4. Carbon Abatement and Emissions Associated with the Gasification of Walnut Shells for Bioenergy and Biochar Production

    PubMed Central

    Pujol Pereira, Engil Isadora; Suddick, Emma C.; Six, Johan

    2016-01-01

    By converting biomass residue to biochar, we could generate power cleanly and sequester carbon resulting in overall greenhouse gas emissions (GHG) savings when compared to typical fossil fuel usage and waste disposal. We estimated the carbon dioxide (CO2) abatements and emissions associated to the concurrent production of bioenergy and biochar through biomass gasification in an organic walnut farm and processing facility in California, USA. We accounted for (i) avoided-CO2 emissions from displaced grid electricity by bioenergy; (ii) CO2 emissions from farm machinery used for soil amendment of biochar; (iii) CO2 sequestered in the soil through stable biochar-C; and (iv) direct CO2 and nitrous oxide (N2O) emissions from soil. The objective of these assessments was to pinpoint where the largest C offsets can be expected in the bioenergy-biochar chain. We found that energy production from gasification resulted in 91.8% of total C offsets, followed by stable biochar-C (8.2% of total C sinks), offsetting a total of 107.7 kg CO2-C eq Mg-1 feedstock. At the field scale, we monitored gas fluxes from soils for 29 months (180 individual observations) following field management and precipitation events in addition to weekly measurements within three growing seasons and two tree dormancy periods. We compared four treatments: control, biochar, compost, and biochar combined with compost. Biochar alone or in combination with compost did not alter total N2O and CO2 emissions from soils, indicating that under the conditions of this study, biochar-prompted C offsets may not be expected from the mitigation of direct soil GHG emissions. However, this study revealed a case where a large environmental benefit was given by the waste-to-bioenergy treatment, addressing farm level challenges such as waste management, renewable energy generation, and C sequestration. PMID:26963623

  5. OAK RIDGE Y-12 PLANT BIOLOGICAL MONITORING AND ABATEMENT PROGRAM (BMAP) PLAN

    SciTech Connect

    ADAMS, S.M.; BRANDT, C.C.; CHRISTENSEN, S.W.; CICERONE, D.S.; GREELEY, M.S.JR; HILL, W.R.; HUSTON, M.S.; KSZOS, L.A.; MCCARTHY, J.F.; PETERSON, M.J.; RYON, M.G.; SMITH, J.G.; SOUTHWORTH, G.R.; STEWART, A.J.

    1998-10-01

    The proposed Biological Monitoring and Abatement Program (BMAP) for East Fork Poplar Creek (EFPC) at the Oak Ridge Y-12 Plant, as described, will be conducted for the duration of the National Pollutant Discharge Elimination System permit issued for the Y-12 Plant on April 28, 1995, and which became effective July 1, 1995. The basic approach to biological monitoring used in this program was developed by the staff in the Environmental Sciences Division at the Oak Ridge National Laboratory at the request of Y- 12 Plant personnel. The proposed BMAP plan is based on results of biological monitoring conducted since 1985. Details of the specific procedures used in the current routine monitoring program are provided but experimental designs for future studies are described in less detail. The overall strategy used in developing this plan was, and continues to be, to use the results obtained from each task to define the scope of future monitoring efforts. Such efforts may require more intensive sampling than initially proposed in some areas (e.g., additional toxicity testing if initial results indicate low survival or reproduction) or a reduction in sampling intensity in others (e.g., reduction in the number of sampling sites when no impact is observed). By using the results of previous monitoring efforts to define the current program and to guide us in the development of future studies, an effective integrated monitoring program has been developed to assess the impacts of the Y-12 Plant operation on the biota of EFPC and to document the ecological effects of remedial actions.

  6. Carbon Abatement and Emissions Associated with the Gasification of Walnut Shells for Bioenergy and Biochar Production.

    PubMed

    Pujol Pereira, Engil Isadora; Suddick, Emma C; Six, Johan

    2016-01-01

    By converting biomass residue to biochar, we could generate power cleanly and sequester carbon resulting in overall greenhouse gas emissions (GHG) savings when compared to typical fossil fuel usage and waste disposal. We estimated the carbon dioxide (CO2) abatements and emissions associated to the concurrent production of bioenergy and biochar through biomass gasification in an organic walnut farm and processing facility in California, USA. We accounted for (i) avoided-CO2 emissions from displaced grid electricity by bioenergy; (ii) CO2 emissions from farm machinery used for soil amendment of biochar; (iii) CO2 sequestered in the soil through stable biochar-C; and (iv) direct CO2 and nitrous oxide (N2O) emissions from soil. The objective of these assessments was to pinpoint where the largest C offsets can be expected in the bioenergy-biochar chain. We found that energy production from gasification resulted in 91.8% of total C offsets, followed by stable biochar-C (8.2% of total C sinks), offsetting a total of 107.7 kg CO2-C eq Mg-1 feedstock. At the field scale, we monitored gas fluxes from soils for 29 months (180 individual observations) following field management and precipitation events in addition to weekly measurements within three growing seasons and two tree dormancy periods. We compared four treatments: control, biochar, compost, and biochar combined with compost. Biochar alone or in combination with compost did not alter total N2O and CO2 emissions from soils, indicating that under the conditions of this study, biochar-prompted C offsets may not be expected from the mitigation of direct soil GHG emissions. However, this study revealed a case where a large environmental benefit was given by the waste-to-bioenergy treatment, addressing farm level challenges such as waste management, renewable energy generation, and C sequestration. PMID:26963623

  7. Theoretical studies of the dynamics of chemical reactions

    SciTech Connect

    Wagner, A.F.

    1993-12-01

    Recent research effort has focussed on several reactions pertinent to combustion. The formation of the formyl radical from atomic hydrogen and carbon monoxide, recombination of alkyl radicals and halo-alkyl radicals with halogen atoms, and the thermal dissociation of hydrogen cyanide and acetylene have been studied by modeling. In addition, the inelastic collisions of NCO with helium have been investigated.

  8. A Spectral, Chemical and Mineralogical Study of Mars Analogue Rocks

    NASA Technical Reports Server (NTRS)

    Bishop, J. L.; Pieters, C. M.; Dyar, M. D.; Hamilton, V. E.; Harloff, J.

    2002-01-01

    The macroscopic and microscopic properties of basaltic and andesitic rocks are under study for integration of diverse spectroscopic approaches to evaluate the composition and texture of Mars materials using both in situ and remote sensing techniques. Additional information is contained in the original extended abstract.

  9. Theoretical Studies in Chemical Kinetics - Annual Report, 1970.

    DOE R&D Accomplishments Database

    Karplus, Martin

    1970-10-01

    The research performed includes (a) Alkali-Halide, Alkali-Halide (MX, M’X’) Exchange Reactions; (b) Inversion Problem; (c) Quantum Mechanics of Scattering Processes, (d) Transition State Analysis of Classical Trajectories, (e) Differential Cross Sections from Classical Trajectories; and (f) Other Studies.

  10. DS-OPTIMAL DESIGNS FOR STUDYING COMBINATIONS OF CHEMICALS USING MULTIPLE FIXED-RATIO RAY EXPERIMENTS

    EPA Science Inventory

    ABSTRACT

    Detecting and characterizing interactions among chemicals is an important environmental issue. Traditional factorial designs become infeasible as the number of compounds under study increases. Ray designs, which reduce the amount of experimental effort, can be...

  11. CHEMICALLY ACTIVE FLUID BED FOR SOX CONTROL. VOLUME I. PROCESS EVALUATION STUDIES

    EPA Science Inventory

    The report describes selected process evaluation studies supporting the development of an atmospheric-pressure, fluidized-bed, chemically active gasification process, using a regenerative limestone sulfur sorbent to produce low- to intermediate-Btu fuel gas. Limestone sorbent sel...

  12. Study of chemical reactions under the influence of ultrasound

    SciTech Connect

    Lee, Kien-Yin.

    1993-01-01

    At Los Alamos the author is interested in sonochemistry because there is potential for accelerating reactions involving the synthesis of certain nitro compounds and for reducing the possibility of decomposition under milder reaction conditions. The author has initiated the study of the nitration of 2,4-dihydro-3H-1,2,4-triazol-3-one with concentrated nitric acid under sonication. The preparation of 3,6-bis(3,5-dimethylpyrazol-1-yl)-1,2-dihydro-1,2,4,5-tetrazine, and oxidation of 3,6-diamino-1,2,4,5-tetrazine were also studied. Sonication reaction conditions and results of these reactions under ultrasound are discussed in detail.

  13. Study of chemical reactions under the influence of ultrasound

    SciTech Connect

    Lee, Kien-Yin

    1993-07-01

    At Los Alamos the author is interested in sonochemistry because there is potential for accelerating reactions involving the synthesis of certain nitro compounds and for reducing the possibility of decomposition under milder reaction conditions. The author has initiated the study of the nitration of 2,4-dihydro-3H-1,2,4-triazol-3-one with concentrated nitric acid under sonication. The preparation of 3,6-bis(3,5-dimethylpyrazol-1-yl)-1,2-dihydro-1,2,4,5-tetrazine, and oxidation of 3,6-diamino-1,2,4,5-tetrazine were also studied. Sonication reaction conditions and results of these reactions under ultrasound are discussed in detail.

  14. Combustion Research Program: Flame studies, laser diagnostics, and chemical kinetics

    SciTech Connect

    Crosley, D.R.

    1991-01-22

    We have made a detailed study of the care that must be taken to correctly measure OH radical concentrations in flames. A large part of these studies has concerned collisional quenching of hydride radical species (OH, NH, and NH{sub 2}), in particular the dependence upon rotational level and collision velocity (temperature). The results on OH and NH have shown unique and interesting behavior from the viewpoint of fundamental molecular dynamics, pointing to quenching often governed by collisions on an anisotropic, attractive surface, whereas NH{sub 2} quenching appears to depend on state-mixing considerations, not dynamic control. This state-specific behavior of these small, theoretically tractable hydrides has direct ramifications for quantitative flame diagnostics. Our other effort in the diagnostic area has been repeated but unsuccessful searches for laser induced fluorescence in the vinyl radical.

  15. Physico-chemical study of Vaikrānta bhasma

    PubMed Central

    Tripathi, R.; Rathore, A. S.; Mehra, B. L.; Raghubir, R.

    2013-01-01

    Background: Vaikrānta has very important place in Rasa śāstra and is placed under Mahārasa and Upratna group. It has been mentioned that vaikrānta can be used in the place of diamond, which is a very precious stone and whose use is beyond the limit of the common man. Vaikrānta possesses pharmacological and therapeutic properties similar to diamond, but still very few researchers have worked on it. Aims and Objectives: The main aim of the present study is to analyze vaikrānta bhasma by employing various organoleptic methods mentioned in Ayurvedic science along with analysis as per tools available today. Settings and Design: In the present study, vaikrānta bhasma was prepared according to method mentioned in Rasa Ratna Samuccaya. Final product is prepared according to classical parameters described in Ayurvedic science. Materials and Methods: Ayurvedic scholars have described various parameters for the qualitative evaluation of vaikrānta bhasma, but all those are subjective in nature and cannot be evaluated numerically for reproducibility of the result. With this in mind, in the present study, tests as per Ayurvedic science and analytical parameters such as scanning electron microscopy, energy dispersive X-ray analysis, Fourier transform infrared spectrometry and inductively coupled plasma spectrometry were adopted to analyze the final product. Results and Conclusions: Data suggests that vaikrānta bhasma is a multi-mineral compound, which contains iron and silica as major constituents and others are present as trace elements. The data obtained in this study suggest that quality specifications for vaikrānta bhasma can be developed using tests described in Ayurvedic science along with analytical tools available today. PMID:24991067

  16. Blood Pressure Changes and Chemical Constituents of Particulate Air Pollution: Results from the Healthy Volunteer Natural Relocation (HVNR) Study

    PubMed Central

    Wu, Shaowei; Deng, Furong; Huang, Jing; Wang, Hongyi; Shima, Masayuki; Wang, Xin; Qin, Yu; Zheng, Chanjuan; Wei, Hongying; Hao, Yu; Lv, Haibo; Lu, Xiuling

    2012-01-01

    Background: Elevated blood pressure (BP) has been associated with particulate matter (PM) air pollution, but associations with PM chemical constituents are still uncertain. Objectives: We investigated associations of BP with various chemical constituents of fine PM (PM2.5) during 460 repeated visits among a panel of 39 university students. Methods: Resting BP was measured using standardized methods before and after the university students relocated from a suburban campus to an urban campus with different air pollution contents in Beijing, China. Air pollution data were obtained from central monitors close to student residences. We used mixed-effects models to estimate associations of various PM2.5 constituents with systolic BP (SBP), diastolic BP (DBP), and pulse pressure. Results: An interquartile range increase of 51.2 μg/m3 in PM2.5 was associated with a 1.08-mmHg (95% CI: 0.17, 1.99) increase in SBP and a 0.96-mmHg (95% CI: 0.31, 1.61) increase in DBP on the following day. A subset of PM2.5 constituents, including carbonaceous fractions (organic carbon and elemental carbon), ions (chloride and fluoride), and metals/metalloid elements (nickel, zinc, magnesium, lead, and arsenic), were found to have robust positive associations with different BP variables, though robust negative associations of manganese, chromium, and molybdenum with SBP or DBP also were observed. Conclusions: Our results support relationships between specific PM2.5 constituents and BP. These findings have potential implications for the development of pollution abatement strategies that maximize public health benefits. PMID:23086577

  17. Shape controllers enhance the efficiency of graphene-TiO2 hybrids in pollutant abatement

    NASA Astrophysics Data System (ADS)

    Sordello, F.; Odorici, E.; Hu, K.; Minero, C.; Cerruti, M.; Calza, P.

    2016-02-01

    The addition of graphene nanoplatelets (GNP) to TiO2 nanoparticles (NPs) has been recently considered as a method to improve the photocatalytic efficiency of TiO2 by favoring charge carrier separation. Here, we show that it is possible to improve the efficiency of GNP-TiO2 composites by controlling the shape, stability, and facets of TiO2 NPs grown on GNP functionalized with either COOH or NH2 groups, while adding ethylendiamine (EDA) and oleic acid (OA) during a hydrothermal synthesis. We studied the photocatalytic activity of all synthesized materials under UV-A light using phenol as a target molecule. GNP-TiO2 composites synthesized on COOH-functionalized GNP, exposing {101} facets, were more efficient at abating phenol than those synthesized on NH2-functionalized GNP, exposing {101} and {100} facets. However, neither of these composites was stable under irradiation. The addition of both OA and EDA stabilized the materials under irradiation; however, only the composite prepared on COOH-functionalized GNP in the presence of EDA showed a significant increase in phenol degradation rate, leading to results that were better than those obtained with TiO2 alone. This result can be attributed to Ti-OH complexation by EDA, which protects GNP from oxidation. The orientation of the most reducing {101} facets toward GNP and the most oxidizing {100} facets toward the solution induces faster phenol degradation owing to a better separation of the charge carriers.The addition of graphene nanoplatelets (GNP) to TiO2 nanoparticles (NPs) has been recently considered as a method to improve the photocatalytic efficiency of TiO2 by favoring charge carrier separation. Here, we show that it is possible to improve the efficiency of GNP-TiO2 composites by controlling the shape, stability, and facets of TiO2 NPs grown on GNP functionalized with either COOH or NH2 groups, while adding ethylendiamine (EDA) and oleic acid (OA) during a hydrothermal synthesis. We studied the photocatalytic

  18. Proliferation of chemical weapons: putting the genie back in the bottle. Study project

    SciTech Connect

    Weekly, T.M.

    1989-02-24

    Following the introduction of gas warfare in World War I, there developed a set of restraints which were effective in preventing the use of toxic chemical agents in World War II. The prolonged Korean and Vietnam conflicts were fought, again without resort to toxic chemical weapons. Recently, however, there has been a breakdown of the traditional restraints which were effective for fifty years in preventing chemical warfare. This study examines the traditional restraint system that evolved after World War I and extrapolates that framework into the modern era to determine what has changed to render the traditional restraints ineffective today. From this analysis, a model is derived for an effective chemical weapons protocol, and a strategy is proposed for worldwide chemical disarmament.

  19. Chemical and spectroscopic studies of Cercidium praecox gum exudate.

    PubMed

    León de Pinto, G; Martínez, M; Rivas, C

    1994-07-01

    The structure of the polysaccharide from Cercidium praecox (R&P) Harms gum exudate has been studied by Smith degradation, by sugar and methylation analyses, and by 13C NMR spectroscopy. The results showed a (1-->4)-xylan core. Some xylose residues are substituted at O-2 by alpha-D-glucuronic acid and 4-O-methyl-alpha-D-glucuronic acid residues. beta-D-Glucuronic acid is present, probably as terminal residues. The arabinose is present as alpha-L-furanose and beta-L-pyranose. PMID:8062287

  20. Surface studies relevant to silicon carbide chemical vapor deposition

    NASA Technical Reports Server (NTRS)

    Stinespring, C. D.; Wormhoudt, J. C.

    1989-01-01

    Reactions of C2H4, C3H8, and CH4 on the Si(111) surface and C2H4 on the Si(100) surface were investigated for surface temperatures in the range of 1062-1495 K. Results led to the identification of the reaction products, a characterization of the solid-state transport process, a determination of the nucleation mechanism and growth kinetics, and an assessment of orientation effects. Based on these results and on the modeling studies of Stinespring and Wormhoudt (1988) on the associated gas phase chemistry, a physical model for the two-step beta-SiC CVD process is proposed.

  1. Quantum chemical study of penicillin: Reactions after acylation

    NASA Astrophysics Data System (ADS)

    Li, Rui; Feng, Dacheng; Zhu, Feng

    The density functional theory methods were used on the model molecules of penicillin to determine the possible reactions after their acylation on ?-lactamase, and the results were compared with sulbactam we have studied. The results show that, the acylated-enzyme tetrahedral intermediate can evolves with opening of ?-lactam ring as well as the thiazole ring; the thiazole ring-open products may be formed via ?-lactam ring-open product or from tetrahedral intermediate directly. Those products, in imine or enamine form, can tautomerize via hydrogen migration. In virtue of the water-assisted, their energy barriers are obviously reduced.

  2. Coordinated Chemical and Isotopic Studies of GEMS in IDPS

    NASA Technical Reports Server (NTRS)

    Keller, L. P.; Messenger, S.

    2008-01-01

    Cometary IDPs contain a record of the building blocks of the solar system including presolar grains, molecular cloud material, and materials formed in the early solar nebula [1]. Following their accretion, these materials have remained relatively unaltered because of the lack of parent body hydrothermal alteration. We are using coordinated transmission electron microscope (TEM) and ion microprobe studies to establish the origins of the various components within cometary IDPs. Of particular interest is the nature and abundance of presolar silicates in these IDPs because astronomical observations suggest that crystalline and amorphous silicates are the dominant grain types produced in young main sequence stars and evolved O-rich stars [e.g. 2]. Amorphous silicates (in the form of GEMS grains) are a major component of cometary IDPs and so a major objective of this work is to elucidate their origins. In rare cases, GEMS grains have highly anomalous O isotopic compositions that establish their origins as circumstellar condensates [3]. Here we present data on a systematic study of the silicate components within a primitive IDP.

  3. Ionic imbalance, in addition to molecular crowding, abates cytoskeletal dynamics and vesicle motility during hypertonic stress

    PubMed Central

    Nunes, Paula; Roth, Isabelle; Meda, Paolo; Féraille, Eric; Brown, Dennis; Hasler, Udo

    2015-01-01

    Cell volume homeostasis is vital for the maintenance of optimal protein density and cellular function. Numerous mammalian cell types are routinely exposed to acute hypertonic challenge and shrink. Molecular crowding modifies biochemical reaction rates and decreases macromolecule diffusion. Cell volume is restored rapidly by ion influx but at the expense of elevated intracellular sodium and chloride levels that persist long after challenge. Although recent studies have highlighted the role of molecular crowding on the effects of hypertonicity, the effects of ionic imbalance on cellular trafficking dynamics in living cells are largely unexplored. By tracking distinct fluorescently labeled endosome/vesicle populations by live-cell imaging, we show that vesicle motility is reduced dramatically in a variety of cell types at the onset of hypertonic challenge. Live-cell imaging of actin and tubulin revealed similar arrested microfilament motility upon challenge. Vesicle motility recovered long after cell volume, a process that required functional regulatory volume increase and was accelerated by a return of extracellular osmolality to isosmotic levels. This delay suggests that, although volume-induced molecular crowding contributes to trafficking defects, it alone cannot explain the observed effects. Using fluorescent indicators and FRET-based probes, we found that intracellular ATP abundance and mitochondrial potential were reduced by hypertonicity and recovered after longer periods of time. Similar to the effects of osmotic challenge, isovolumetric elevation of intracellular chloride concentration by ionophores transiently decreased ATP production by mitochondria and abated microfilament and vesicle motility. These data illustrate how perturbed ionic balance, in addition to molecular crowding, affects membrane trafficking. PMID:26045497

  4. A Pilot Study To Define Chemical Coping in Cancer Patients Using the Delphi Method

    PubMed Central

    Hui, David; Bruera, Eduardo

    2015-01-01

    Abstract Background: “Chemical coping” is a commonly used term in the pain and palliative care literature, but is heterogeneously defined. We conducted a Delphi survey among palliative care and pain specialists internationally to identify a consensus definition for “chemical coping with opioids” and warning signs for chemical coping. Methods: This Delphi survey consisted of two rounds on the following: (1) concepts and definition related to chemical coping, (2) warning signs for chemical coping, and (3) demographics. Consensus in this study was defined as agreement by a minimum of 70% of the experts. Results: Participating in the first round were 14/19 (74%) physicians; 12/14 (86%) participated in the second round. The international experts reached the following consensus definition for chemical coping with opioids (92% agreement): “The use of opioids to cope with emotional distress, characterized by inappropriate and/or excessive opioid use.” They also identified depression (consensus 93%); psychiatric disease (86%); a history of substance abuse (86%); a positive score for the Cut-down, Annoyed, Guilty, and Eye-opener (CAGE) alcoholism screening test (79%); a history of alcoholism (79%); and a history of smoking (71%) as important warning signs for chemical coping. Conclusion: Our expert panel reached a consensus definition for chemical coping and related warning signs, which may help clinicians and researchers to identify patients at risk of opioid misuse. PMID:25922879

  5. Chemical Degradation Studies on a Series of Dithiophosphinic Acids

    SciTech Connect

    Freiderich, Melissa E; Delmau, Laetitia Helene; Peterman, D. R.; Marc, Philippe L; Klaehn, John D.

    2014-01-01

    In this study a significant increase in the stability of a series of dithiophosphinic acids (DPAHs) under oxidizing acidic conditions was achieved. The degradation behavior of a series of DPAHs, designed for lanthanide/actinide separation, was examined. The stability of the DPAHs, when contacted with varying nitric acid concentrations, was tested and monitored using 31P {1H} NMR. Changes in the functional groups of the DPAHs resulted in substantial increases in the stability. However, all the DPAHs eventually showed signs of degradation when placed in contact with 2 M HNO3. The addition of a radical scavenger, hydrazine, inhibited the degradation of the DPAHs. With small amounts of hydrazine, five of the DPAHs remained stable for over a month in direct contact with 2 M HNO3.

  6. Advanced Theoretical Studies for Chemical Identification of the Heaviest Elements

    NASA Astrophysics Data System (ADS)

    Pershina, V.

    2015-06-01

    Both relativistic Dirac-Fock (DF) correlated, CCSD(T), and the density-functional theory (DFT) methods with various GGA exchange-correlation potentials agree on an increase in the M-Au bond strength from M = Cn to Fl. This means that the adsorption energy of Fl on gold, as measured by gas-phase chromatography experiments, must be larger for Fl than for Cn. For the weak (van der Waals) interactions, the trend to an increase in bonding from Cn2 to Fl2 obtained at the DFT level of theory is also confirmed by the DF CCSD(T) calculations. Thus, for comparative studies, relativistic DFT is a very reliable and efficient tool. First calculations of adsorption of TlOH and element 113OH on a hydroxylated quartz surface are reported.

  7. Chemical composition and Biological studies of Ficus benjamina

    PubMed Central

    2014-01-01

    Background Current study has been designed to estimate the possible antioxidant, antimicrobial and hemolytic potential of Ficus benjamina different parts (leaves, stem and root). Results All examined extracts and fractions were significantly rich in antioxidants and exhibited potent antimicrobial activity. GC/MS analysis of essential oil identified four compounds in stem and eight compounds in root, respectively. HPLC analysis indicated four phenolic compounds (chlorogenic, p-coumaric, ferulic and syringic acids) in roots, three (chlorogenic p-coumaric and ferulic acids) in stem and only one (caffeic acid) in leaves. Extracts of all three parts of F. benjamina exhibited substantial hemolytic activity. Conclusions Considering these results, it is concluded that F. benjamina can be used as a potential source for the exploration of new antioxidant compounds and antimicrobial agents. PMID:24524349

  8. Studies of coupled chemical and catalytic coal conversion methods

    SciTech Connect

    Stock, L.M.

    1990-01-01

    During the previous quarter, a new approach for the deploymerization of the coal macromolecule was tried. This was aimed towards carbon-carbon bond cleavage in presence of strong bases. Such bond cleavage reactions are well known with the alkali metals. Electron transfer reactions take place from the metals to the aromatic nuclei resulting in the formation ofanion-radicals (or dianions) which subsequently undergo carbon-carbon bond cleavage. In our work instead of using the alkali metals, we have used strong bases to cleave the carbon-carbon bonds in hydrocarbons, and have suggested that hydrocarbon elimination reactions occur. Such anionic fragmentation reactions involving strong bases are not very well established. However, we have obtained circumstantial evidence that such bond cleavage reactions do take place in some coal systems. For example, when the high rank Lower Kittaming coal, PSOC 1197, was treated with Lochmann's base (equimolar mixture of n-butyllithiun and potassium tert-butoxide) in refluxing heptane and quenched with ammonium chloride and reethanol, the pyridine solubility of the product increased from 5% (raw coal) to 39%. A similar increase in solubility due to base treatment was also observed in a separate study for another high rank coal, Pocahontas No. 3 from the Argonne National Laboratory Premium Sample Program. The solubility of the coal increased frcm 5% to 32% after the base treatment. These results, together with the absence of literature studies on base promoted fragmentation reactions prompted us to perfom reactions on some pure compounds to assess this concept in more detail.

  9. A chemical study of individual green glasses and brown glasses from 15426 - Implications for their petrogenesis

    NASA Technical Reports Server (NTRS)

    Ma, M.-S.; Liu, Y.-G.; Schmitt, R. A.

    1982-01-01

    Systematic chemical analyses of individual Apollo 15 green glasses were performed in order to: (1) study chemical variations among them; (2) understand their petrogenesis and source region; and (3) study their possible relationships with mare basalts in general. Brown glasses were also analyzed in order to study their chemical variations and their petrogenetic relationships to green glasses and mare basalts. The chemical composition of green and brown glasses is shown and variation diagrams of Sc, Cr2O3, FeO, and Co abundances in green glasses are presented. Igneous fractionation, two component magma mixing, and partial melting of heterogeneous source materials are alternate scenarios to explain strong observed correlations. The composition of green glasses indicates that they were derived by partial melting of the fractionated cumulate source materials formed from a magma ocean which had experienced certain degrees of olivine and plagioclase fractional crystallization.

  10. The storage lipids in Tangier disease. A physical chemical study.

    PubMed

    Katz, S S; Small, D M; Brook, J G; Lees, R S

    1977-06-01

    The physical states and phase behavior of the lipids of the spleen, liver, and splenic artery from a 38-yr-old man with Tangier disease were studied. Many intracellular lipid droplets in the smectic liquid crystalline state were identified by polarizing microscopy in macrophages in both the spleen and liver, but not in the splenic artery. The droplets within individual cells melted sharply over a narrow temperature range, indicating a uniform lipid composition of the droplets of each cell. However different cells melted over a wide range, 20-53 degrees C indicating heterogeneity of lipid droplet composition between cells. Furthermore, most of the cells (81%) had droplets in the liquid crystalline state at 37 degrees C. X-ray diffraction studies of splenic tissue at 37 degrees C revealed a diffraction pattern typical of cholesterol esters in the smectic liquid crystalline state. Differential scanning calorimetry of spleen showed a broad reversible transition from 29-52 degrees C, with a maximum mean transition temperature at 42 degrees C, correlating closely with the polarizing microscopy observations. The enthalpy of the transition, 0.86+/-0.07 cal/g of cholesterol ester, was quantitatively similar to that of the liquid crystalline to liquid transition of pure cholesterol esters indicating that nearly all of the cholesterol esters in the tissue were free to undergo the smectic-isotropic phase transition. Lipid compositions of spleen and liver were determined, and when plotted on the cholesterol-phospholipid-cholesterol ester phase diagram, fell within the two phase zone. The two phases, cholesterol ester droplets and phospholipid bilayers were isolated by ultracentrifugation of tissue homogenates. Lipid compositions of the separated phases approximated those predicted by the phase diagram. Extracted lipids from the spleen, when dispersed in water and ultracentrifuged, underwent phase separation in a similar way. Thus (a) most of the storage lipids in the liver and

  11. Quantum chemical study of the catalytic oxidative coupling of methane

    SciTech Connect

    Onal, I.; Senkan, S.

    1997-10-01

    Oxidative coupling of methane reaction pathways on MgO and lithium-modified MgO were theoretically studied using the semiempirical MNDO-PM3 molecular orbital method. The surface of the MgO catalyst was modeled by a Mg{sub 9}O{sub 9} molecular cluster containing structural defects such as edges and corners. Lithium-promoted magnesia was simulated by isomorphic substitution of Mg{sup 2+} by Li{sup +}; the excess negative charge of the cluster was compensated by a proton connected to a neighboring O{sup 2{minus}} site. Heterolytic adsorption of methane was found to be directly related to the coordination number of both the lattice oxygen and the metal sites. Energetically the most favorable site pair was Mg{sub 3c}-O{sub 3c} with a neighboring Li{sub 4c} site present. Various sequential oxygen and methane adsorption pathways were explored resulting in CH{sub 3}OH formation with lower energy barriers for the Li-modified MgO cluster as compared to unmodified MgO.

  12. [Study on antioxidant chemical constituents of Lonicera japonica leaves].

    PubMed

    Zhang, Yong-xin; Zhang, Qi-wei; Li, Chun; Liu, Su

    2015-06-01

    Guided by the antioxidant activity, the EtOAc-soluble and n-butanol-soluble fractions of the 50% methanol extract of Lonicera japonica leaves were isolated and purified by various chromatorgraphic methods, and the structures were identified by spectral analysis and comparison to the data reported in literature. As a result, nine compounds were obtained and identified as 5-O-caffeoylquinicacid (1), chlorogenicacid (2), 4-O-caffeoylquinicacid (3), luteolin-7-O-[α-L-arabinopyranosyl-(1 --> 6)] -β-D-glucopyranoside (4), luteoloside (5), 3,4-di-O-caffeoylquinic acid (6), 3,5-di-O-caffeoylquinic acid (7), 4, 5-di-O-caffeoylquinic acid (8) and luteolin (9). The antioxidant activity of the nine compounds were determined by using DPPH free radical scavenging method, and ascorbic acid was used as a positive control. Their antioxidant activities from high to low were 5 > 9 > 2 > 8 > 7 > 6 > 1 > 3 > 4. Among them, luteoloside (5) had the strongest antioxidant activity with an IC50 of 0.018 18 g x L(-1), and luteolin (IC50 0.023 6 g x L(-1)) and chlorogenicacid (IC50 0.035 17 g x L(-1)) ranks No. 2 and 3. Furthermore, the antioxidant activity of luteoloside and luteolin were stronger than that of ascorbic acid (IC50 0.027 54 g x L(-1)). These results gave a basis for the further study and utilization of L. japonica leaves. PMID:26591528

  13. Long-term aging of elastomers: Chemical stress relaxation of fluorosilicone rubber and other studies

    NASA Technical Reports Server (NTRS)

    Kalfayan, S. H.; Mazzeo, A. A.; Silver, R. H.

    1971-01-01

    Aerospace applications of elastomers are considered, including: propellant binders, bladder materials for liquid propellant expulsion systems, and fuel tank sealants for high-speed aircraft. A comprehensive molecular theory for mechanical properties of these materials has been developed but has only been tested experimentally in cases where chemical degradation processes are excluded. Hence, a study is being conducted to ascertain the nature, extent, and rate of chemical changes that take place in some elastomers of interest. Chemical changes that may take place in the fluorosilicone elastomer, LS 420, which is regarded as a fuel and high-temperature-resistant rubber are investigated. The kinetic analysis of the chemical stress relaxation and gel permeation chromatography studies comprise the major portion of the report.

  14. Selection of adduct-forming chemicals for human-monitoring studies

    SciTech Connect

    Not Available

    1991-07-01

    The U.S. EPA, through its Environmental Monitoring Systems Laboratory-Las Vegas (EMSL-LV) and its Health Effects Research Laboratory-Research Triangle Park (HERL-RTP) has been exploring the feasibility of using biological markers to monitor exposure to environmental chemicals. The participants began by compiling a list of chemicals of known or suspected health hazards and for which the potential for human exposure exists. The chemicals on the master list were then systematically evaluated for: (1) the potential for adduct-formation in vivo, (2) the availability of supportive adduct research data, (3) the identifiability of exposed population(s), and (4) the level of genetic activity. After considering all the relevant data, the participants selected and prioritized for further study a small group of chemicals considered to have the greatest potential for use in pilot, adduct-based, biological monitoring studies in human populations.

  15. Abatement of SO2-NOx binary gas mixtures using a ferruginous active absorbent: Part I. Synergistic effects and mechanism.

    PubMed

    Han, Yinghui; Li, Xiaolei; Fan, Maohong; Russell, Armistead G; Zhao, Yi; Cao, Chunmei; Zhang, Ning; Jiang, Genshan

    2015-04-01

    A novel ferruginous active absorbent, prepared by fly ash, industrial lime and the additive Fe(VI), was introduced for synchronous abatement of binary mixtures of SO2-NOx from simulated coal-fired flue gas. The synergistic action of various factors on the absorption of SO2 and NOx was investigated. The results show that a strong synergistic effect exists between Fe(VI) dose and reaction temperature for the desulfurization. It was observed that in the denitration process, the synergy of Fe(VI) dose and Ca/(S+N) had the most significant impact on the removal of NO, followed by the synergy of Fe(VI) and reaction temperature, and then the synergy of reaction temperature and flue gas humidity. A scanning electron microscope (SEM) and an accessory X-ray energy spectrometer (EDS) were used to observe the surface characteristics of the raw and spent absorbent as well as fly ash. A reaction mechanism was proposed based on chemical analysis of sulfur and nitrogen species concentrations in the spent absorbent. The Gibbs free energy, equilibrium constants and partial pressures of the SO2-NOx binary system were determined by thermodynamics. PMID:25872709

  16. High temperature abatement of acid gases from waste incineration. Part I: experimental tests in full scale plants.

    PubMed

    Biganzoli, Laura; Racanella, Gaia; Rigamonti, Lucia; Marras, Roberto; Grosso, Mario

    2015-02-01

    In recent years, several waste-to-energy plants in Italy have experienced an increase of the concentration of acid gases (HCl, SO2 and HF) in the raw gas. This is likely an indirect effect of the progressive decrease of the amount of treated municipal waste, which is partially replaced by commercial waste. The latter is characterised by a higher variability of its chemical composition because of the different origins, with possible increase of the load of halogen elements such as chlorine (Cl) and fluorine (F), as well as of sulphur (S). A new dolomitic sorbent was then tested in four waste-to-energy plants during standard operation as a pre-cleaning stage, to be directly injected at high temperature in the combustion chamber. For a sorbent injection of about 6 kg per tonne of waste, the decrease of acid gases concentration downstream the boiler was in the range of 7-37% (mean 23%) for HCl, 34-95% (mean 71%) for SO2 and 39-80% (mean 63%) for HF. This pre-abatement of acid gases allowed to decrease the feeding rate of the traditional low temperature sorbent (sodium bicarbonate in all four plants) by about 30%. Furthermore, it was observed by the plant operators that the sorbent helps to keep the boiler surfaces cleaner, with a possible reduction of the fouling phenomena and a consequent increase of the specific energy production. A preliminary quantitative estimate was carried out in one of the four plants. PMID:25465511

  17. STM-based methodologies for molecular identification and studies of chemical reaction mechanisms

    SciTech Connect

    Hamers, R.J.

    1995-12-01

    The use of STM to study chemical reactions has been hampered by the general inability to identify molecules and molecular fragments on surfaces. By combining the ability of the STM to probe local electronic structure with systematic study as a function of temperature and concepts from coordination chemistry, a priori chemical identification can be achieved, and this information can be used to elucidate new information about the mechanisms of chemical reactions. On silicon, this approach has been applied to study the decomposition of disilane, phosphine, and diborane. On metals, the delocalized bonding necessitates different approaches. We have also applied STM and tunneling spectroscopy to study the adsorption and decomposition of thiophene and related molecules on Ag(111) surfaces at 120 Kelvin. Here, voltage-dependent STM imaging is used to identify the rotational orientation of the molecules and to study polymerization at the molecular level. Methodologies for molecular identification will be discussed, with recent applications on semiconductors and metals.

  18. Chemical and geochemical studies off the coast of Washington. Progress report, September 1980-July 1981

    SciTech Connect

    Carpenter, R.

    1981-07-01

    This report summarizes progress from September 1980 through July 1981 on a series of marine chemical and geochemical investigations involving both laboratory studies and field studies off the coast of Washington. Most of the field work has been on the Washington continental shelf, slope, and the submarine canyons indenting the shelf north of the Columbia River. The aim is to provide basic data required to characterize underlying chemical and physical processes and their rates which control the distributions, concentrations, and ultimate fate of some of the potentially hazardous agents associated with fossil fuel and/or nuclear power production or transportation. We are concentrating on several processes which we feel are of special importance in the sea, and developing methodologies and expertise to study them. Laboratory and field experiments and theories derived from them are being used iteratively to investigate: (1) vertical transfer of trace chemicals from surface seawaters to underlying waters and sediments; (2) processes which may transfer certain chemicals from sediments back into the overlying water column; (3) redox processes which besides changing valence states of certain chemicals may alter their precipitation/dissolution tendencies, their biological availability and/or toxicity; and (4) accumulation histories of potentially hazardous chemicals in sediments during the past 100 years.

  19. Chemical and geochemical studies off the coast of Washington. Progress report, September 1981-July 1982

    SciTech Connect

    Carpenter, R.

    1982-07-01

    Progress is reported on a series of marine chemical and geochemical investigations involving both laboratory studies and field studies off the coast of Washington. Most of the field work the past few years has been on the Washington continental shelf, slope, and the submarine canyons indenting the shelf north of the Columbia River. The aim is to provide basic data required to characterize underlying chemical and physical processes and their rates which control the distributions, concentrations, and ultimate fate of some of the potentially hazardous agents associated with fossil fuel and/or nuclear power production or transportation. Several processes of special importance in the sea, and methodologies and expertise to study them are being emphasized. Laboratory and field experiments and theories derived from them are being used iteratively to investigate: vertical transfer of trace chemicals from surface seawaters to underlying waters and sediments; processes which may transfer certain chemicals from sediments back into the overlying water column; redox processes which besides changing valence states of certain chemicals may alter their precipitation/dissolution tendencies, their biological availability and/or toxicity; and accumulation histories of potentially hazardous chemicals in sediments during the past 100 years.

  20. Adolescents Exiting Homelessness Over Two Years: The Risk Amplification and Abatement Model.

    PubMed

    Milburn, Norweeta G; Rice, Eric; Rotheram-Borus, Mary Jane; Mallett, Shelley; Rosenthal, Doreen; Batterham, Phillip; May, Susanne J; Witkin, Andrea; Duan, Naihua

    2009-12-01

    The Risk Amplification and Abatement Model (RAAM), demonstrates that negative contact with socializing agents amplify risk, while positive contact abates risk for homeless adolescents. To test this model, the likelihood of exiting homelessness and returning to familial housing at 2 years and stably exiting over time are examined with longitudinal data collected from 183 newly homeless adolescents followed over 2 years in Los Angeles, CA. In support of RAAM, unadjusted odds of exiting at 2 years and stably exiting over2 years revealed that engagement with pro-social peers, maternal social support, and continued school attendance all promoted exiting behaviors. Simultaneously, exposure to family violence and reliance on shelter services discouraged stably exiting behaviors. Implications for family-based interventions are proposed. PMID:25067896

  1. The hydrogen sulfide emissions abatement program at the Geysers Geothermal Power Plant

    NASA Technical Reports Server (NTRS)

    Allen, G. W.; Mccluer, H. K.

    1974-01-01

    The scope of the hydrogen sulfide (H2S) abatement program at The Geysers Geothermal Power Plant and the measures currently under way to reduce these emissions are discussed. The Geysers steam averages 223 ppm H2S by weight and after passing through the turbines leaves the plant both through the gas ejector system and by air-stripping in the cooling towers. The sulfide dissolved in the cooling water is controlled by the use of an oxidation catalyst such as an iron salt. The H2S in the low Btu ejector off gases may be burned to sulfur dioxide and scrubbed directly into the circulating water and reinjected into the steam field with the excess condensate. Details are included concerning the disposal of the impure sulfur, design requirements for retrofitting existing plants and modified plant operating procedures. Discussion of future research aimed at improving the H2S abatement system is also included.

  2. Candidate-Gene Screening and Association Analysis at the Autism-Susceptibility Locus on Chromosome 16p: Evidence of Association at GRIN2A and ABAT

    PubMed Central

    Barnby, Gabrielle; Abbott, Aaron; Sykes, Nuala; Morris, Andrew; Weeks, Daniel E.; Mott, Richard; Lamb, Janine; Bailey, Anthony J.; Monaco, Anthony P.

    2005-01-01

    Autism is a highly heritable neurodevelopmental disorder whose underlying genetic causes have yet to be identified. To date, there have been eight genome screens for autism, two of which identified a putative susceptibility locus on chromosome 16p. In the present study, 10 positional candidate genes that map to 16p11-13 were examined for coding variants: A2BP1, ABAT, BFAR, CREBBP, EMP2, GRIN2A, MRTF-B, SSTR5, TBX6, and UBN1. Screening of all coding and regulatory regions by denaturing high-performance liquid chromatography identified seven nonsynonymous changes. Five of these mutations were found to cosegregate with autism, but the mutations are not predicted to have deleterious effects on protein structure and are unlikely to represent significant etiological variants. Selected variants from candidate genes were genotyped in the entire International Molecular Genetics Study of Autism Consortium collection of 239 multiplex families and were tested for association with autism by use of the pedigree disequilibrium test. Additionally, genotype frequencies were compared between 239 unrelated affected individuals and 192 controls. Patterns of linkage disequilibrium were investigated, and the transmission of haplotypes across candidate genes was tested for association. Evidence of single-marker association was found for variants in ABAT, CREBBP, and GRIN2A. Within these genes, 12 single-nucleotide polymorphisms (SNPs) were subsequently genotyped in 91 autism trios (one affected individual and two unaffected parents), and the association was replicated within GRIN2A (Fisher's exact test, P<.0001). Logistic regression analysis of SNP data across GRIN2A and ABAT showed a trend toward haplotypic differences between cases and controls. PMID:15830322

  3. Multimedia-based decision support system for hazards recognition and abatement

    DOEpatents

    Czachowski, John B.; Zoldak, John T.

    1998-01-01

    A system for monitoring a site includes a portable data collection module used in the field to collect site specific data, and a processor module located at a central location. The data collection module displays choices of categories of findings, and then specific findings within each category. A selected specific finding is then displayed in report form with a citation to the specific code or statutory requirement, as well as a recommended course of action and an abatement date.

  4. Abating climate change. What will be done and the consequences for investors

    SciTech Connect

    Raskin, A.; Mellquist, N.; Shah, S.; Winton, B.

    2008-01-15

    This report is meant for institutional investors. Sections discuss: the science of climate change; global emissions - abatement scenario; coal - the world's dominant fuel for electric generation; CO{sub 2} transport and storage; nuclear energy - the new green solution; renewable energy - harnessing the power of water, wind and sun; regulation; increasing energy efficiency - the lowest cost option; enhancing the efficiency of electric applications; enhancing the efficiency of transportation; macroeconomic implications; and investment implications.

  5. Achieving CO2 reductions in Colombia: Effects of carbon taxes and abatement targets

    SciTech Connect

    Calderón, Silvia; Alvarez, Andres Camilo; Loboguerrero, Ana Maria; Arango, Santiago; Calvin, Katherine; Kober, Tom; Daenzer, Kathryn; Fisher-Vanden, Karen

    2015-06-03

    In this paper we investigate CO2 emission scenarios for Colombia and the effects of implementing carbon taxes and abatement targets on the energy system. By comparing baseline and policy scenario results from two integrated assessment partial equilibrium models TIAM-ECN and GCAM and two general equilibrium models Phoenix and MEG4C, we provide an indication of future developments and dynamics in the Colombian energy system. Currently, the carbon intensity of the energy system in Colombia is low compared to other countries in Latin America. However, this trend may change given the projected rapid growth of the economy and the potential increase in the use of carbon-based technologies. Climate policy in Colombia is under development and has yet to consider economic instruments such as taxes and abatement targets. This paper shows how taxes or abatement targets can achieve significant CO2 reductions in Colombia. Though abatement may be achieved through different pathways, taxes and targets promote the entry of cleaner energy sources into the market and reduce final energy demand through energy efficiency improvements and other demand-side responses. The electric power sector plays an important role in achieving CO2 emission reductions in Colombia, through the increase of hydropower, the introduction of wind technologies, and the deployment of biomass, coal and natural gas with CO2 capture and storage (CCS). Uncertainty over the prevailing mitigation pathway reinforces the importance of climate policy to guide sectors toward low-carbon technologies. This paper also assesses the economy-wide implications of mitigation policies such as potential losses in GDP and consumption. As a result, an assessment of the legal, institutional, social and environmental barriers to economy-wide mitigation policies is critical yet beyond the scope of this paper.

  6. Achieving CO2 reductions in Colombia: Effects of carbon taxes and abatement targets

    DOE PAGESBeta

    Calderón, Silvia; Alvarez, Andres Camilo; Loboguerrero, Ana Maria; Arango, Santiago; Calvin, Katherine; Kober, Tom; Daenzer, Kathryn; Fisher-Vanden, Karen

    2015-06-03

    In this paper we investigate CO2 emission scenarios for Colombia and the effects of implementing carbon taxes and abatement targets on the energy system. By comparing baseline and policy scenario results from two integrated assessment partial equilibrium models TIAM-ECN and GCAM and two general equilibrium models Phoenix and MEG4C, we provide an indication of future developments and dynamics in the Colombian energy system. Currently, the carbon intensity of the energy system in Colombia is low compared to other countries in Latin America. However, this trend may change given the projected rapid growth of the economy and the potential increase inmore » the use of carbon-based technologies. Climate policy in Colombia is under development and has yet to consider economic instruments such as taxes and abatement targets. This paper shows how taxes or abatement targets can achieve significant CO2 reductions in Colombia. Though abatement may be achieved through different pathways, taxes and targets promote the entry of cleaner energy sources into the market and reduce final energy demand through energy efficiency improvements and other demand-side responses. The electric power sector plays an important role in achieving CO2 emission reductions in Colombia, through the increase of hydropower, the introduction of wind technologies, and the deployment of biomass, coal and natural gas with CO2 capture and storage (CCS). Uncertainty over the prevailing mitigation pathway reinforces the importance of climate policy to guide sectors toward low-carbon technologies. This paper also assesses the economy-wide implications of mitigation policies such as potential losses in GDP and consumption. As a result, an assessment of the legal, institutional, social and environmental barriers to economy-wide mitigation policies is critical yet beyond the scope of this paper.« less

  7. Socio-economic impact analysis: Centralia mine fire abatement alternatives. Draft report

    SciTech Connect

    Not Available

    1980-11-07

    The overall purpose of information contained in the following text is to document the likely social and economic impacts upon the Borough of Centralia through implementation of various mine fire abatement alternatives. Much of the data presented herein and utilized in preparing conclusions and recommendations have been derived from those individuals whose lives are now, or may eventually be, impacted by the underground mine fire.

  8. The effect of noise-abatement profiles on noise immissions and human annoyance underneath a subsequent climbpath

    NASA Technical Reports Server (NTRS)

    Garbell, Maurice A.

    1990-01-01

    En route noise emissions on the ground can be affected by the detailed characteristics of intended noise-abatement climb profiles and procedures to an extent of 10 or more nautical miles from the start of the takeoff roll of a large or heavy air-carrier-type aircraft. Suggestions submitted to the noise abatement officials of the airports at Frankfurt, Federal Republic of Germany, and Zurick, Switzerland, and the aircarriers Lufthansa German Airlines and SWISSAIR are explained and discussed.

  9. The effect of noise-abatement profiles on noise immissions and human annoyance underneath a subsequent climbpath

    NASA Astrophysics Data System (ADS)

    Garbell, Maurice A.

    1990-04-01

    En route noise emissions on the ground can be affected by the detailed characteristics of intended noise-abatement climb profiles and procedures to an extent of 10 or more nautical miles from the start of the takeoff roll of a large or heavy air-carrier-type aircraft. Suggestions submitted to the noise abatement officials of the airports at Frankfurt, Federal Republic of Germany, and Zurick, Switzerland, and the aircarriers Lufthansa German Airlines and SWISSAIR are explained and discussed.

  10. Chemical and geochemical studies off the coast of Washington. Progress report, September 1982-July 1983

    SciTech Connect

    Carpenter, R.

    1983-07-01

    This report summarizes progress from September 1982 through July 1983 on a series of marine chemical and geochemical investigations involving both laboratory studies and field studies off the coast of Washington. Most field work the past few years has been on the Washington continental shelf, slope, and the submarine canyons indenting the shelf north of the Columbia River. Our aim is to provide basic data required to characterize underlying chemical and physical processes and their rates which control the distributions, concentrations, and ultimate fate of some of the potentially hazardous agents associated with fossil fuel and/or nuclear power production or transportation. Laboratory and field experiments and theories derived from them are being used iteratively to investigate: (1) vertical transfer or trace chemicals from surface seawaters to underlying waters and sediments; (2) processes which may transfer certain chemicals from sediments back into the overlying water column; (3) redox processes which besides changing valence states of certain chemicals may alter their precipitation/dissolution tendencies, their biological availability and/or toxicity; and (4) accumulation histories of potentialy hazardous chemicals in sediments during the past 100 years.

  11. Microwave plasma torch abatement of NF{sub 3} and SF{sub 6}

    SciTech Connect

    Hong, Yong Cheol; Uhm, Han Sup; Chun, Byung Jun; Lee, Sun Ku; Hwang, Sang Kyu; Kim, Dong Su

    2006-03-15

    An atmospheric pressure microwave plasma torch as a tool for fluorinated compounds (FCs) abatement was presented. Detailed experiments were conducted on the abatement of NF{sub 3} and SF{sub 6} in terms of destruction and removal efficiency (DRE) using Fourier transform infrared (FTIR). Swirl gas, compressed air for stable plasma, was tangentially injected into the microwave plasma torch and a mixture of N{sub 2}, NF{sub 3}, or SF{sub 6}, and C{sub 2}H{sub 4} was axially injected. The DRE of 99.1% for NF{sub 3} was achieved without an additive gas at the total flow rate of 50.1 liters per minute (lpm) by applying a microwave power of 1.4 kW. Also, a DRE of SF{sub 6} up to 90.1% was obtained at the total flow rate of 40.6 lpm using an applied microwave power of 1.4 kW. Experimental results indicate that the microwave plasma abatement device can successfully eliminate FCs in the semiconductor industry.

  12. A study of chemical remediation on 1,2,4-Trichlorobenzene in groundwater

    NASA Astrophysics Data System (ADS)

    Ye, S.

    2015-12-01

    Shujun Ye, Guanqun Wang, and Jichun WuKey Laboratory of Surficial Geochemistry, Ministry of Education; School of Earth Sciences and Engineering, Nanjing University, Nanjing 210093, China, Nanjing, 210093, China; sjye@nju.edu.cn The ground water is contaminated by 1,2,4 Trichlorobenzene (TCB) in a former chemical plant in Nanjing, China. So 1,2,4-TCB is the contaminant of concern in this study. As chemical oxidation technology is a common in-site remediation technique, hydrogen peroxide, sodium sulfate and the two-mixed oxidants under the catalytic condition are used to remove 1,2,4-TCB from groundwater. By changing the values of temperature and pH in the experiments, the best conditions for chemical oxidation with oxidants mentioned above were determined. The fluorescent brightener of PF, manufactured by the former chemical plant, was added to groundwater to evaluate whether its existence made an impact on the chemical oxidation. 1-D sand column tests were conducted to study the degradation effect by using the chemical oxidation technology. The experiment results showed that single oxidant and mixed both oxidants can remove 1,2,4-TCB completely. The oxidation efficiency of both oxidants is influenced by temperature and pH. For hydrogen peroxide, the oxidation efficiency decreases with the increase of pH, while, for sodium sulfate, the efficiency is high under the mild acidic condition. The fluorescent brightener PF has an impact on the oxidation efficiency, with negative effect on the oxidation with hydrogen peroxide but positive effect with sodium sulfate. 1-D sand column tests testified the degradation of 1,2,4-TCB by the chemical oxidation with hydrogen peroxide and sodium sulfate. KEY WORDS: 1,2,4-trichlorobenzene hydrogen peroxide sodium persulfate optical brightener PF chemical oxidation AcknowledgementsFunding for this research from DuPont Company and NSFC Project No. 41472212.

  13. An Informatics Approach to Evaluating Combined Chemical Exposures from Consumer Products: A Case Study of Asthma-Associated Chemicals and Potential Endocrine Disruptors

    PubMed Central

    Gabb, Henry A.; Blake, Catherine

    2016-01-01

    exposures from consumer products: a case study of asthma-associated chemicals and potential endocrine disruptors. Environ Health Perspect 124:1155–1165; http://dx.doi.org/10.1289/ehp.1510529 PMID:26955064

  14. Miscellaneous chemical basin treatability study: an analysis of passive soil vapor extraction wells (PSVE)

    SciTech Connect

    Riha, B.; Rossabi, J.

    1997-12-01

    A passive soil vapor extraction (PSVE) treatability study at the Miscellaneous Chemical Basin (MCB) of the Savannah River Site (SRS) has been progressing since September 1996. The results to date on the treatability study of the PSVE system indicate that the technology is performing well.

  15. The Role of Some Individual Differences in Understanding Chemical Changes: A Study in Secondary Education

    ERIC Educational Resources Information Center

    Kypraios, Nikolaos; Papageorgiou, George; Stamovlasis, Dimitrios

    2014-01-01

    In this study, students' understanding of chemical changes was investigated in relation to four individual differences, related to logical thinking, field dependence/independence, convergence and divergence thinking. The study took place in Greece with the participation of students (n = 374) from three grades (8th, 10th and 12th grades) of…

  16. Recent studies of nuclear and chemical properties of elements 103, 104 and 105

    SciTech Connect

    Hoffman, D.C. . Dept. of Chemistry Lawrence Berkeley Lab., CA )

    1990-08-01

    Information obtained since 1983 on the nuclear and chemical properties of element 103, the last on the actinide series, and elements 104 and 105, at the beginning of the transactinide series, is reviewed. Their chemical properties are compared with their lanthanide and lighter group 4 and 5 homologs and evidence for possible relativistic effects is discussed. The current knowledge of the nuclear properties of these elements and how these affect of the study of chemical properties is discussed. Some of the challenges involved in the study of short-lived isotopes which can only be produced an atom-at-a-time'' at an appropriate accelerator and the prognosis for future studies of these and still heavier elements are considered. 40 refs., 4 figs.

  17. Physico-Chemical Structural and Electrical Studies of Cu-Zn Ferrites Synthesized by Novel Chemical Route

    NASA Astrophysics Data System (ADS)

    Lohar, K. S.; Patange, S. M.; Mane, D. R.; Shirsath, Sagar E.; Shinde, N. D.; Kulkarni, Nilesh

    The physico-chemical, structural and electrical properties of zinc substituted copper ferrites having the general formula Cu1-xZnxFe2O4 (x=0.0 to x=0.8) have been studied as a function of zinc ion concentration. The sample was prepared by co-precipitation method from corresponding metal sulphates. X-ray diffraction patterns were used to confirm the structure of synthesized samples. The calculated and theoretical values of average lattice constant, tetrahedral bond, tetrahedral edge and unshared octahedral edge were found to increase, while the shared octahedral edge and octahedral bond decrease as the Zn ion concentration increases. The dielectric constant (ε‧) and dielectric loss tangent (tan δ) were measured at a constant frequency 1 kHz as a function of temperature. The dielectric constant and loss tangent were found to increase with rise in temperature. The conduction mechanism in these ferrites is discussed on the basis of electron exchange between Fe2+ and Fe3+ ions. The temperature dependent dc resistivity was carried out in the temperature range 300 to 800 K. The plots of log ρ versus 103/T are linear showing two regions, corresponding to ferrimagnetic and paramagnetic regions.

  18. Hypothesis for induction and propagation of chemical sensitivity based on biopsy studies.

    PubMed

    Meggs, W J

    1997-03-01

    The reactive airways dysfunction syndrome (RADS), the reactive upper airways dysfunction syndrome (RUDS), the sick building syndrome (SBS), and the multiple chemical sensitivity syndrome (MCS) are overlapping disorders in which there is an intolerance to environmental chemicals. The onset of these illnesses is often associated with an initial acute chemical exposure. To understand the pathophysiology of these conditions, a study of the nasal pathology of individuals experiencing these syndromes was undertaken. Preliminary data indicate that the nasal pathology of these disorders is characterized by defects in tight junctions between cells, desquamation of the respiratory epithelium, glandular hyperplasia, lymphocytic infiltrates, and peripheral nerve fiber proliferation. These findings suggest a model for a relationship between the chronic inflammation seen in these conditions and an individual's sensitivity to chemicals. A positive feedback loop is set up: the inflammatory response to low levels of chemical irritants is enhanced due to the observed changes in the epithelium, and the epithelial changes are propagated by the inflammatory response to the chemicals. This model, combined with the concept of neurogenic switching, has the potential to explain many aspects of RADS, RUDS, SBS, and MCS in a unified way. PMID:9167982

  19. Laboratory Studies of Homogeneous and Heterogeneous Chemical Processes of Importance in the Upper Atmosphere

    NASA Technical Reports Server (NTRS)

    Molina, Mario J.

    2003-01-01

    The objective of this study was to conduct measurements of chemical kinetics parameters for reactions of importance in the stratosphere and upper troposphere, and to study the interaction of trace gases with ice surfaces in order to elucidate the mechanism of heterogeneous chlorine activation processes, using both a theoretical and an experimental approach. The measurements were carried out under temperature and pressure conditions covering those applicable to the stratosphere and upper troposphere. The main experimental technique employed was turbulent flow-chemical ionization mass spectrometry, which is particularly well suited for investigations of radical-radical reactions.

  20. Physico-chemical studies of radiation effects in cells: Final report

    SciTech Connect

    Powers, E.L.

    1987-03-01

    The career of Dr. E.L. Powers, a pioneer in the development of radiobiology, is reviewed. His initial research involved the effects of radiation and certain chemicals on Paramecium, associated ultrastructural studies on protozoan cells, responses of Rickettsia and bacteriophage to irradiation, and the development of techniques for studying bacterial spores. These efforts established the basic radiation biology of the spore and its importance in understanding the effects of free radicals, oxygen, and water. His recent research extended work on the dry spore to the very wet spore and to other selected chemical systems in aqueous suspension. 126 refs., 2 figs.

  1. Chemical compatibility study of Cooley L18KU, Herculite, and Elephant Mat with Hanford tank waste

    SciTech Connect

    Mercado, J.E.

    1998-06-23

    An independent chemical compatibility review of various wrapping and absorbent/padding materials was conducted to evaluate resistance to chemicals and constituents present in liquid waste from the Hanford underground tanks. These materials will be used to wrap long-length contaminated equipment when such equipment is removed from the tanks and prepared for transportation and subsequent disposal or storage. The materials studied were Cooley L18KU, Herculite, and Elephant Mat. The study concludes that these materials are appropriate for use in this application.

  2. Model gases for the detailed study of microscopic chemical nonequilibrium in diatomic gas flows

    NASA Technical Reports Server (NTRS)

    Kunc, Joseph A.; Muntz, E. Phillip; Weaver, David P.

    1990-01-01

    It is shown that chlorine (Cl2) and iodine (I2) are suitable model diatomic gases to use in theoretical studies of chemical nonequilibrium that account for rotational and vibrational as well as electronic processes in a gas. Because of the low temperature at which significant dissociation can be achieved in iodine, it is a particularly attractive candidate for the study of relatively low temperature chemically reacting flows, permitting detailed knowledge of the nonequilibrium populations of translational, rotational, vibrational and electronic energy levels. A preliminary investigation indicates that a useful iodine flow facility can be constructed and that diagnostic techniques are available to validate in detail prediction techniques for nonequilibrium flows.

  3. Late-gestation heat stress abatement on performance and behavior of Holstein dairy cows.

    PubMed

    Karimi, M T; Ghorbani, G R; Kargar, S; Drackley, J K

    2015-10-01

    The objective of this study was to evaluate cooling to lessen the effects of heat stress during the last 3 wk of gestation on performance and behavior of multiparous Holstein cows. Twenty nonlactating cows were randomly assigned to treatments approximately 21 d before their expected calving date based on mature equivalent milk production and parity. Treatments were only imposed during the last 3 wk of gestation and included heat stress (HT; n=10) and cooling (CL; n=10), both under a similar photoperiod (14 h of light and 10 h of dark). Dry cows were housed in a sand-bedded stall with the stall areas for CL cows equipped with sprinklers and fans that were on from 0700 to 1900 h, whereas those for the HT cows were not. After parturition, all cows were housed in a barn with cooling devices. Rectal temperatures were measured daily at 1400 h and respiration rates were recorded by counting the flank movements for 1 min at 1500 h on odd days over the last 3 wk of gestation to calving. Daily dry matter intake was measured from -21 d relative to expected calving to 21 d after calving and milk production was recorded daily up to 180 d in milk. Behavioral changes of dry cows were studied continuously for 24 h at -10 d relative to expected calving. The average temperature-humidity index during the last 3 wk of gestation was 69.7 and was not significantly different between treatments. Heat-stressed cows exhibited greater rectal temperatures (39.5 vs. 39.2°C), greater respiration rates (70.4 vs. 63.3 breaths/min), and decreased dry matter intake (13.7 vs. 15.5 kg/d) compared with CL cows. Compared with HT cows, CL cows produced more milk during 180 d in milk (40.5 vs. 44.6 kg/d). Heat stress decreased ruminating (243.2 vs. 282.5 min/d) and chewing times (390.6 vs. 448.7 min/d) at -10 d before calving. The CL cows had shorter standing times than their HT counterparts (390.4 vs. 474.0 min/d). These results confirm that heat stress abatement in the late gestation period improves

  4. The Rainbow Trout Liver Cancer Model: Response to Environmental Chemicals and Studies on Promotion and Chemoprevention✰

    PubMed Central

    Williams, David E.

    2011-01-01

    Rainbow trout (Oncorhynchus mykiss) are an outstanding model of liver cancer induction by environmental chemicals and development of strategies for chemoprevention. Trout have critical and unique advantages allowing for cancer studies with 40,000 animals to determine dose-response at levels orders of magnitude lower than possible in rodents. Examples of two promoters in this model, the dietary supplement dehydroepiandrosterone (DHEA) and industrial chemical perfluorooctanoic acid (PFOA), are presented. In addition, indole-3-carbinol (I3C) and chlorophyllin (CHL) inhibit initiation following exposure to potent human chemical carcinogens (e.g., aflatoxin B1 (AFB1). Two “ED001” cancer studies have been conducted, utilizing approximately 40,000 trout, by dietary exposure to AFB1 and dibenzo[d,e,f,p]chrysene (DBC). These studies represent the two largest cancer studies ever performed and expand the dose-response dataset generated by the 25,000 mouse “ED01” study over an order of magnitude. With DBC, the liver tumor response fell well below the LED10 line, often used for risk assessment, even though the biomarker (liver DBC-DNA adducts) remained linear. Conversely, the response with AFB1 remained relatively linear throughout the entire dose range. These contributions to elucidation of mechanisms of liver cancer, induced by environmental chemicals and the remarkable datasets generated with ED001 studies, make important contributions to carcinogenesis and chemoprevention. PMID:21704190

  5. TREATABILITY STUDIES USED TO TEST FOR EXOTHERMIC REACTIONS OF PLUTONIUM DECONTAMINATION CHEMICALS

    SciTech Connect

    EWALT, J.R.

    2005-06-06

    Fluor Hanford is decommissioning the Plutonium Finishing Plant (PFP) at the Hanford site in Eastern Washington. Aggressive chemicals are commonly used to remove transuranic contaminants from process equipment to allow disposal as low level waste. Chemicals being considered for decontamination of gloveboxes in PFP include cerium(IV) nitrate in a nitric acid solution, and proprietary commercial solutions that include acids, degreasers, and sequestering agents. Fluor's decontamination procedure involves application of chemical solutions as a spray on the contaminated surfaces, followed by a wipe-down with rags. This process effectively transfers the transuranic materials to the decontamination liquids, which are then absorbed by rags and packaged for disposal as TRU waste. Concerns regarding the safety of this procedure developed following a fire at Rocky Flats in 2003. The fire occurred in a glovebox that had been treated with cerium nitrate, which is one of the decontamination chemicals that Fluor Hanford has proposed to use. The investigation of the event was hampered by the copious use of chemicals and water to extinguish the fire, and was not conclusive regarding the cause. However, the reviewers noted that rags were found in the glovebox, suggesting that the combination of rags and chemicals may have contributed to the fire. With that uncertainty, Fluor began an investigation into the potential for fire when using the chemicals and materials in the decontamination process. The focus of this work has been to develop a disposal strategy that will provide a chemically stable waste form at expected Hanford waste storage temperatures. Treatability tests under CERCLA were used to assess the use of certain chemicals and wipes during the decontamination process. Chemicals being considered for decontamination of gloveboxes at PFP include cerium (IV) nitrate in a nitric acid solution, and proprietary commercial solutions as RadPro{trademark} that include acids, degreasers

  6. Studies on the chemical composition of kohl stone by X-ray diffractometer.

    PubMed

    Ullah, Pervaiz Habib; Mahmood, Zafar Alam; Sualeh, Mohammad; Zoha, S M S

    2010-01-01

    Use of Kohl (Surma) creates toxicity or protects eye, is one of the most controversial topic of modern medicines. However, modern researches show that kohl forms a thin film on the eye lens thus avoiding the direct contract of harmful UV radiation and glare of sun with lens. Black and shining particles of galena in kohl shield the eyes from glare and reflection of sun and thus protect them from harmful effect of UV radiation emerging from the sun. Based on these findings and other properties of kohl, it was decided to undertake this study to ascertain it's chemical composition and to correlate these properties scientifically. In the present study, kohl stone obtained from Madina (Saudi Arabia) was analyzed to ascertain it's chemical composition. The chemical analysis and X-ray diffractometer results obtained, showed that the main component of kohl stone is galena (PbS). PMID:20067866

  7. In vitro model systems for studying the impact of organic chemicals on the skin barrier lipids.

    PubMed

    Groen, Daniël; Berthaud, Fabienne; Bouwstra, Joke A; Chapuis, Christian; Gooris, Gert S; Boncheva, Mila

    2014-01-01

    This paper describes two synthetic lipid models designed to replace human stratum corneum (SC) in studies of the impact of volatile organic chemicals on the molecular organization of the skin barrier lipids. The models built upon previously developed self-assembled lipid membranes which have composition and 3D organization similar to those of the lipid matrix in SC. In one model the target chemicals were incorporated in the lipids before their self-assembly, and in the other one they were applied on top of a preformed lipid membrane. The chemicals could be incorporated within the model membranes in quantities close to those reached within human SC upon heavy surface loading. The dose-dependent effects of the chemicals on the lateral molecular organization in the models were qualitatively identical to those observed by infrared spectroscopy in human SC. The models facilitated the interpretation of X-ray diffraction profiles used to determine the nature of the interactions between the chemicals and the lipid lamellae and the position of the exogenous molecules within the unit cell of the lipid phases. These model systems are suitable for in vitro studies in the areas of skin biophysics, dermatology, transdermal drug delivery, and risk assessment. PMID:24125684

  8. What Can Epidemiological Studies Tell Us about the Impact of Chemical Mixtures on Human Health?

    PubMed Central

    Braun, Joseph M.; Gennings, Chris; Hauser, Russ; Webster, Thomas F.

    2016-01-01

    Summary Humans are exposed to a large number of environmental chemicals: Some of these may be toxic, and many others have unknown or poorly characterized health effects. There is intense interest in determining the impact of exposure to environmental chemical mixtures on human health. As the study of mixtures continues to evolve in the field of environmental epidemiology, it is imperative that we understand the methodologic challenges of this research and the types of questions we can address using epidemiological data. In this article, we summarize some of the unique challenges in exposure assessment, statistical methods, and methodology that epidemiologists face in addressing chemical mixtures. We propose three broad questions that epidemiological studies can address: a) What are the potential health impacts of individual chemical agents? b) What is the interaction among agents? And c) what are the health effects of cumulative exposure to multiple agents? As the field of mixtures research grows, we can use these three questions as a basis for defining our research questions and for developing methods that will help us better understand the effect of chemical exposures on human disease and well-being. PMID:26720830

  9. Possibilities of detecting health effects by studies of populations exposed to chemicals from waste disposal sites.

    PubMed Central

    Buffler, P A; Crane, M; Key, M M

    1985-01-01

    Factors affecting the design of an epidemiologic study assessing possible health effects from chemical waste disposal sites are reviewed. Such epidemiologic studies will most likely be prompted either by a known release of chemicals into the environment around the site, or by an unusual disease cluster in a population near the site. In the latter situation, a method for evaluating the health effects is needed, and one possible approach is discussed. In the former situation, it may not be obvious what health outcomes are relevant. Reported associations between health effects and chemicals in humans were reviewed. Studies from the occupational and environmental literature were classified by chemical and target organ affected and presented in tabular form. No attempt was made to critically evaluate the quality of evidence for each health effect, although bibliographic documentation was provided where possible. Episodes of chemical contamination of food, drinking water and other media were also reviewed and presented in a separate table. The organ sites likely to be affected by toxic chemicals from waste disposal sites depend heavily on the route of exposure and the dose that is received. Ingestion is the most frequently reported route of exposure in episodes of environmental contamination. These have affected the hepatic, renal, hematopoietic, reproductive, and central nervous systems. The type and severity of effects were dose-dependent. Direct skin contact is important in the occupational environment where dermal and central nervous system effects have been reported but seems less likely as a route of exposure for populations around waste disposal sites. Inhalation, unless at relative high concentrations or as a result of fire, is unlikely to be important, although hematopoietic, reproductive, and central nervous system effects have been reported in occupational studies. PMID:3910420

  10. Modelling road dust emission abatement measures using the NORTRIP model: Vehicle speed and studded tyre reduction

    NASA Astrophysics Data System (ADS)

    Norman, M.; Sundvor, I.; Denby, B. R.; Johansson, C.; Gustafsson, M.; Blomqvist, G.; Janhäll, S.

    2016-06-01

    Road dust emissions in Nordic countries still remain a significant contributor to PM10 concentrations mainly due to the use of studded tyres. A number of measures have been introduced in these countries in order to reduce road dust emissions. These include speed reductions, reductions in studded tyre use, dust binding and road cleaning. Implementation of such measures can be costly and some confidence in the impact of the measures is required to weigh the costs against the benefits. Modelling tools are thus required that can predict the impact of these measures. In this paper the NORTRIP road dust emission model is used to simulate real world abatement measures that have been carried out in Oslo and Stockholm. In Oslo both vehicle speed and studded tyre share reductions occurred over a period from 2004 to 2006 on a major arterial road, RV4. In Stockholm a studded tyre ban on Hornsgatan in 2010 saw a significant reduction in studded tyre share together with a reduction in traffic volume. The model is found to correctly simulate the impact of these measures on the PM10 concentrations when compared to available kerbside measurement data. Importantly meteorology can have a significant impact on the concentrations through both surface and dispersion conditions. The first year after the implementation of the speed reduction on RV4 was much drier than the previous year, resulting in higher mean concentrations than expected. The following year was much wetter with significant rain and snow fall leading to wet or frozen road surfaces for 83% of the four month study period. This significantly reduced the net PM10 concentrations, by 58%, compared to the expected values if meteorological conditions had been similar to the previous years. In the years following the studded tyre ban on Hornsgatan road wear production through studded tyres decreased by 72%, due to a combination of reduced traffic volume and reduced studded tyre share. However, after accounting for exhaust

  11. SO2 ABATEMENT FOR STATIONARY SOURCES IN JAPAN

    EPA Science Inventory

    The report gives results of a study of Japanese government efforts to regulate SOx emissions: the efforts were prompted by serious air pollution problems in Japan during the 1960s. Several technologies are being developed including production of low sulfur gas from coal, fuel des...

  12. FIELD DEMONSTRATION OF LEAD PAINT ABATEMENT TECHNOLOGIES IN RESIDENTIAL HOUSING

    EPA Science Inventory

    This study was conducted to demonstrate lead-based paint (LBP) removal from architectural wood components in CO2 unoccupied residential housing using four technologies: granular carbon dioxide (CO2 blasting), pelletized CO2 blasting, encapsulant paint remover, and wet abrasive bl...

  13. Oil pollution abatement: onshore, offshore, on the high seas

    SciTech Connect

    Shaheen, E.I.; Al- Rashid, N.

    1984-08-01

    Overview of typical sources of oil pollution is presented in this study. Arabian Gulf oil spills and other major oil spill accidents; persistent oils on seawater, their properties and physical changes; sorbents, dispersion with detergents, treating agents in typical processes, booms, skimming, recovery of oil; and the clean-up of oil contaminated beaches are considered.

  14. Using the soil and water assessment tool to estimate dissolved inorganic nitrogen water pollution abatement cost functions in central portugal.

    PubMed

    Roebeling, P C; Rocha, J; Nunes, J P; Fidélis, T; Alves, H; Fonseca, S

    2014-01-01

    Coastal aquatic ecosystems are increasingly affected by diffuse source nutrient water pollution from agricultural activities in coastal catchments, even though these ecosystems are important from a social, environmental and economic perspective. To warrant sustainable economic development of coastal regions, we need to balance marginal costs from coastal catchment water pollution abatement and associated marginal benefits from coastal resource appreciation. Diffuse-source water pollution abatement costs across agricultural sectors are not easily determined given the spatial heterogeneity in biophysical and agro-ecological conditions as well as the available range of best agricultural practices (BAPs) for water quality improvement. We demonstrate how the Soil and Water Assessment Tool (SWAT) can be used to estimate diffuse-source water pollution abatement cost functions across agricultural land use categories based on a stepwise adoption of identified BAPs for water quality improvement and corresponding SWAT-based estimates for agricultural production, agricultural incomes, and water pollution deliveries. Results for the case of dissolved inorganic nitrogen (DIN) surface water pollution by the key agricultural land use categories ("annual crops," "vineyards," and "mixed annual crops & vineyards") in the Vouga catchment in central Portugal show that no win-win agricultural practices are available within the assessed BAPs for DIN water quality improvement. Estimated abatement costs increase quadratically in the rate of water pollution abatement, with largest abatement costs for the "mixed annual crops & vineyards" land use category (between 41,900 and 51,900 € tDIN yr) and fairly similar abatement costs across the "vineyards" and "annual crops" land use categories (between 7300 and 15,200 € tDIN yr). PMID:25602550

  15. CO[subscript 2] Rebreathing: An Undergraduate Laboratory to Study the Chemical Control of Breathing

    ERIC Educational Resources Information Center

    Domnik, N. J.; Turcotte, S. E.; Yuen, N. Y.; Iscoe, S.; Fisher, J. T.

    2013-01-01

    The Read CO[subscript]2 rebreathing method (Read DJ. "A clinical method for assessing the ventilatory response to carbon dioxide." "Australas Ann Med" 16: 20-32, 1967) provides a simple and reproducible approach for studying the chemical control of breathing. It has been widely used since the modifications made by Duffin and…

  16. STUDY OF THE BIOLOGICAL ACTIVITY OF ERIONITE IN RELATION TO ITS CHEMICAL AND STRUCTURAL CHARACTERISTICS

    EPA Science Inventory

    Fibrous erionite appears to have many times the mesothelioma induction potential of asbestos. A member of a class of minerals termed zeolites, it differs markedly from asbestos in many physico-chemical characteristics. For preliminary biological studies, experiments were based on...

  17. Effect of Continuous Assessment on Learning Outcomes on Two Chemical Engineering Courses: Case Study

    ERIC Educational Resources Information Center

    Tuunila, R.; Pulkkinen, M.

    2015-01-01

    In this paper, the effect of continuous assessment on the learning outcomes of two chemical engineering courses is studied over a several-year period. Average grades and passing percentages of courses after the final examination are reported and also student feedback on the courses is collected. The results indicate significantly better learning…

  18. The Competence of Modelling in Learning Chemical Change: A Study with Secondary School Students

    ERIC Educational Resources Information Center

    Oliva, José Mª; del Mar Aragón, María; Cuesta, Josefa

    2015-01-01

    The competence of modelling as part of learning about chemical change is analysed in a sample of 35 secondary students, ages 14-15 years, during their study of a curricular unit on this topic. The teaching approach followed is model based, with frequent use of analogies and mechanical models (fruits and bowls, Lego pieces, balls of plasticine,…

  19. Developing Computer Model-Based Assessment of Chemical Reasoning: A Feasibility Study

    ERIC Educational Resources Information Center

    Liu, Xiufeng; Waight, Noemi; Gregorius, Roberto; Smith, Erica; Park, Mihwa

    2012-01-01

    This paper reports a feasibility study on developing computer model-based assessments of chemical reasoning at the high school level. Computer models are flash and NetLogo environments to make simultaneously available three domains in chemistry: macroscopic, submicroscopic, and symbolic. Students interact with computer models to answer assessment…

  20. A PILOT STUDY TO COMPARE MICROBIAL AND CHEMICAL INDICATORS OF HUMAN FECAL CONTAMINATION IN WATER

    EPA Science Inventory

    Limitations exist in applying traditional microbial methods for the detection of human fecal contamination of water. A pilot study was undertaken to compare the microbial and chemical indicators of human fecal contamination of water. Sixty-four water samples were collected in O...