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Sample records for addition chemical analyses

  1. Biochemical analyses of the antioxidative activity and chemical ingredients in eight different Allium alien monosomic addition lines.

    PubMed

    Yaguchi, Shigenori; Matsumoto, Misato; Date, Rie; Harada, Kazuki; Maeda, Toshimichi; Yamauchi, Naoki; Shigyo, Masayoshi

    2013-01-01

    We measured the antioxidant contents and antioxidative activities in eight Allium fistulosum-shallot monosomic addition lines (MAL; FF+1A-FF+8A). The high antioxidative activity lines (FF+2A and FF+6A) showed high polyphenol accumulation. These additional chromosomes (2A and 6A) would therefore have anonymous genes related to the upregulation of polyphenol production, the antioxidative activities consequently being increased in these MALs. PMID:24317054

  2. Chemical analyses of provided samples

    NASA Technical Reports Server (NTRS)

    Becker, Christopher H.

    1993-01-01

    Two batches of samples were received and chemical analysis was performed of the surface and near surface regions of the samples by the surface analysis by laser ionization (SALI) method. The samples included four one-inch optics and several paint samples. The analyses emphasized surface contamination or modification. In these studies, pulsed sputtering by 7 keV Ar+ and primarily single-photon ionization (SPI) by coherent 118 nm radiation (at approximately 5 x 10(exp 5) W/cm(sup 2) were used. For two of the samples, also multiphoton ionization (MPI) at 266 nm (approximately 5 x 10(exp 11) W/cm(sup 2) was used. Most notable among the results was the silicone contamination on Mg2 mirror 28-92, and that the Long Duration Exposure Facility (LDEF) paint sample had been enriched in K and Na and depleted in Zn, Si, B, and organic compounds relative to the control paint.

  3. Modification of chemical additives to elastomeric compositions

    NASA Astrophysics Data System (ADS)

    Mukhutdinov, A. A.; Grishin, B. S.

    1994-08-01

    The physicochemical principles of the modification of crystalline chemical additives to elastomeric compositions are examined. A classification of various types of modifications based on scientific principles is given. The modifications are subdivided into physical and physicochemical depending on the configuration of the molecules in the crystals, the defectiveness and dispersity of the crystalline particles, the melting points of the crystals, and the presence of necleophilic and electrophylic centres in the molecules of the components of binary and complex eutectic mixtures. The effectiveness of the modification of the chemical additives is determined by the manifestation in binary systems of these components in elastomeric compositions of physical and chemical synergism due to the occurrence of the relevant processes in such systems. A relation has been discovered between the physical and chemical phenomena accompanying the modification of the chemical additives in binary and complex eutectic mixtures, their influence on the properties of the elastomeric composition is examined, the ecological problems associated with the processing of such materials are discussed, and the relation between the structure and properties of the molecules of the additives is analysed using quantum-chemical calculations. The bibliography includes 92 references.

  4. Precise Chemical Analyses of Planetary Surfaces

    NASA Technical Reports Server (NTRS)

    Kring, David; Schweitzer, Jeffrey; Meyer, Charles; Trombka, Jacob; Freund, Friedemann; Economou, Thanasis; Yen, Albert; Kim, Soon Sam; Treiman, Allan H.; Blake, David; Lisse, Carey

    1996-01-01

    We identify the chemical elements and element ratios that should be analyzed to address many of the issues identified by the Committee on Planetary and Lunar Exploration (COMPLEX). We determined that most of these issues require two sensitive instruments to analyze the necessary complement of elements. In addition, it is useful in many cases to use one instrument to analyze the outermost planetary surface (e.g. to determine weathering effects), while a second is used to analyze a subsurface volume of material (e.g., to determine the composition of unaltered planetary surface material). This dual approach to chemical analyses will also facilitate the calibration of orbital and/or Earth-based spectral observations of the planetary body. We determined that in many cases the scientific issues defined by COMPLEX can only be fully addressed with combined packages of instruments that would supplement the chemical data with mineralogic or visual information.

  5. Chemical Analyses of Silicon Aerogel Samples

    SciTech Connect

    van der Werf, I.; Palmisano, F.; De Leo, Raffaele; Marrone, Stefano

    2008-04-01

    After five years of operating, two Aerogel counters: A1 and A2, taking data in Hall A at Jefferson Lab, suffered a loss of performance. In this note possible causes of degradation have been studied. In particular, various chemical and physical analyses have been carried out on several Aerogel tiles and on adhesive tape in order to reveal the presence of contaminants.

  6. Reliability of chemical analyses of water samples

    SciTech Connect

    Beardon, R.

    1989-11-01

    Ground-water quality investigations require reliable chemical analyses of water samples. Unfortunately, laboratory analytical results are often unreliable. The Uranium Mill Tailings Remedial Action (UMTRA) Project`s solution to this problem was to establish a two phase quality assurance program for the analysis of water samples. In the first phase, eight laboratories analyzed three solutions of known composition. The analytical accuracy of each laboratory was ranked and three laboratories were awarded contracts. The second phase consists of on-going monitoring of the reliability of the selected laboratories. The following conclusions are based on two years experience with the UMTRA Project`s Quality Assurance Program. The reliability of laboratory analyses should not be taken for granted. Analytical reliability may be independent of the prices charged by laboratories. Quality assurance programs benefit both the customer and the laboratory.

  7. Environmental monitoring final report: groundwater chemical analyses

    SciTech Connect

    Not Available

    1984-02-01

    This report presents the results of analyses of groundwater qualtiy at the SRC-I Demonstration Plant site in Newman, Kentucky. Samples were obtained from a network of 23 groundwater observation wells installed during previous studies. The groundwater was well within US EPA Interim Primary Drinking Water Standards for trace metals, radioactivity, and pesticides, but exceeded the standard for coliform bacteria. Several US EPA Secondary Drinking Water Standards were exceeded, namely, manganese, color, iron, and total dissolved solids. Based on the results, Dames and Moore recommend that all wells should be sterilized and those wells built in 1980 should be redeveloped. 1 figure, 6 tables.

  8. In situ chemical analyses of extraterrestrial bodies

    NASA Technical Reports Server (NTRS)

    Economou, Thanasis E.; Turkevich, Anthony L.

    1988-01-01

    One of the most important tasks on any sample return mission will have to be a quick sample characterization in order to guarantee a variety of collected samples. An alpha particle instrument with alpha, proton and X-ray modes can provide a quick and almost complete chemical analysis of Mars samples. This instrument is based on three interactions of the alpha particles from a radioactive source with matter: elastic scattering of the alpha particles by nuclei (alpha mode), (alpha,p) nuclear reaction with some light elements (proton mode), and excitation of the atomic structure of atoms by alpha particles, leading to emission of characteristic X-rays of the lunar surface at three sites during the Surveyor mission of 1967 to 1968. Since then the instrument has been improved and miniaturized substantially. As shown in the past, the alpha particle instrument can operate under Martian conditions without any degradation in the performance. The alpha and proton modes can provide vital information about the light elements, while the X-ray mode with its ambient temperature X-ray detector will be useful for the heavier elements. The excitation of the atomic structure is provided by the same alpha radioactive source that is used by alpha and proton modes or by an auxiliary X-ray source that is selected to enhance the sensitivity to some important geochemical elements.

  9. Cucumis monosomic alien addition lines: morphological, cytological, and genotypic analyses.

    PubMed

    Chen, Jin-Feng; Luo, Xiang-Dong; Qian, Chun-Tao; Jahn, Molly M; Staub, Jack E; Zhuang, Fei-Yun; Lou, Qun-Feng; Ren, Gang

    2004-05-01

    Cucumis hystrix Chakr. (HH, 2n=24), a wild relative of the cultivated cucumber, possesses several potentially valuable disease-resistance and abiotic stress-tolerance traits for cucumber ( C. sativus L., CC, 2n=14) improvement. Numerous attempts have been made to transfer desirable traits since the successful interspecific hybridization between C. hystrix and C. sativus, one of which resulted in the production of an allotriploid (HCC, 2n=26: one genome of C. hystrix and two of C. sativus). When this genotype was treated with colchicine to induce polyploidy, two monosomic alien addition lines (MAALs) (plant nos. 87 and 517: 14 CC+1 H, 2n=15) were recovered among 252 viable plants. Each of these plants was morphologically distinct from allotriploids and cultivated cucumbers. Cytogenetic and molecular marker analyses were performed to confirm the genetic constitution and further characterize these two MAALs. Chromosome counts made from at least 30 meristematic cells from each plant confirmed 15 nuclear chromosomes. In pollen mother cells of plant nos. 87 and 517, seven bivalents and one univalent were observed at diakinesis and metaphase I; the frequency of trivalent formation was low (about 4-5%). At anaphase I and II, stochastic and asymmetric division led to the formation of two gamete classes: n=7 and n=8; however, pollen fertility was relatively high. Pollen stainability in plant no. 87 was 86.7% and in plant no. 517 was 93.2%. Random amplified polymorphic DNA analysis was performed using 100 random 10-base primers. Genotypes obtained with eight primers (A-9, A-11, AH-13, AI-19, AJ-18, AJ-20, E-19, and N-20) showed a band common to the two MAAL plants and C. hystrix that was absent in C. sativus, confirming that the alien chromosomes present in the MAALs were derived from C. hystrix. Morphological differences and differences in banding patterns were also observed between plant nos. 87 and 517 after amplification with primers AI-5, AJ-13, N-12, and N-20

  10. Chemical Shuttle Additives in Lithium Ion Batteries

    SciTech Connect

    Patterson, Mary

    2013-03-31

    than NMC) and the DDB is useful for lithium ion cells with LFP cathodes (potential that is lower than NMC). A 4.5 V class redox shuttle provided by Argonne National Laboratory was evaluated which provides a few cycles of overcharge protection for lithium ion cells containing NMC cathodes but it is not stable enough for consideration. Thus, a redox shuttle with an appropriate redox potential and sufficient chemical and electrochemical stability for commercial use in larger format lithium ion cells with NMC cathodes was not found. Molecular imprinting of the redox shuttle molecule during solid electrolyte interphase (SEI) layer formation likely contributes to the successful reduction of oxidized redox shuttle species at carbon anodes. This helps to understand how a carbon anode covered with an SEI layer, that is supposed to be electrically insulating, can reduce the oxidized form of a redox shuttle.

  11. Thyroid disrupting chemicals in plastic additives and thyroid health.

    PubMed

    Andra, Syam S; Makris, Konstantinos C

    2012-01-01

    The globally escalating thyroid nodule incidence rates may be only partially ascribed to better diagnostics, allowing for the assessment of environmental risk factors on thyroid disease. Endocrine disruptors or thyroid-disrupting chemicals (TDC) like bisphenol A, phthalates, and polybrominated diphenyl ethers are widely used as plastic additives in consumer products. This comprehensive review studied the magnitude and uncertainty of TDC exposures and their effects on thyroid hormones for sensitive subpopulation groups like pregnant women, infants, and children. Our findings qualitatively suggest the mixed, significant (α = 0.05) TDC associations with natural thyroid hormones (positive or negative sign). Future studies should undertake systematic meta-analyses to elucidate pooled TDC effect estimates on thyroid health indicators and outcomes. PMID:22690712

  12. 33 CFR 157.31 - Discharges: Chemical additives.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Discharges: Chemical additives. 157.31 Section 157.31 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... OIL IN BULK Vessel Operation § 157.31 Discharges: Chemical additives. No person may use a...

  13. 33 CFR 157.31 - Discharges: Chemical additives.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Discharges: Chemical additives. 157.31 Section 157.31 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... OIL IN BULK Vessel Operation § 157.31 Discharges: Chemical additives. No person may use a...

  14. 33 CFR 157.31 - Discharges: Chemical additives.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Discharges: Chemical additives. 157.31 Section 157.31 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... OIL IN BULK Vessel Operation § 157.31 Discharges: Chemical additives. No person may use a...

  15. 33 CFR 157.31 - Discharges: Chemical additives.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Discharges: Chemical additives. 157.31 Section 157.31 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... OIL IN BULK Vessel Operation § 157.31 Discharges: Chemical additives. No person may use a...

  16. 33 CFR 157.31 - Discharges: Chemical additives.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Discharges: Chemical additives. 157.31 Section 157.31 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... OIL IN BULK Vessel Operation § 157.31 Discharges: Chemical additives. No person may use a...

  17. Chemical analyses for thermal and mineral springs examined in 1982-1983

    SciTech Connect

    Korosec, M.A.

    1984-01-01

    Six water samples from three different spring systems were collected and analyzed for major element concentrations. This report presents the results of those analyses, along with predicted reservoir temperatures using various geothermometers. In addition, a table of chemical analyses from the US Geological Survey for Washington springs not previously reported in state geothermal reports is included.

  18. Chemical Mixture Risk Assessment Additivity-Based Approaches

    EPA Science Inventory

    Powerpoint presentation includes additivity-based chemical mixture risk assessment methods. Basic concepts, theory and example calculations are included. Several slides discuss the use of "common adverse outcomes" in analyzing phthalate mixtures.

  19. Mechanism of concentration addition toxicity: they are different for nonpolar narcotic chemicals, polar narcotic chemicals and reactive chemicals.

    PubMed

    Lin, Zhifen; Du, Jianwei; Yin, Kedong; Wang, Liansheng; Yu, Hongxia

    2004-03-01

    According to the toxicity mechanism of the individual chemicals, the concentration addition toxicity mechanism is revealed for nonpolar-narcotic-chemical mixtures, polar-narcotic-chemical mixtures and reactive-chemical mixtures, respectively. For nonpolar-narcotic-chemical mixtures, the partitioning of individual chemicals from water to biophase was determined, and the result shows that their concentration additive effect results from no competitive partitioning among individual chemicals. For polar-narcotic-chemical mixtures, their toxicity are contributed by two factors (the total baseline toxicity and the hydrogen bond donor activity of individual chemicals), and it is the concentration additive effect for either of these two factors that leads to their concentration addition toxicity. In addition, the interactions between the reactive chemicals and the biological macromolecules are discussed thoroughly. The results suggest that the net effect of these interactions is zero, and it is this zero net effect that leads to the concentration addition toxicity mechanism for reactive-chemical mixtures.

  20. The effect of chemical additives on the synthesis of ethanol

    SciTech Connect

    Chuang, S.S.C.

    1988-11-14

    The objective of this research is to elucidate the role of various chemical additives on ethanol synthesis over Rh- and Ni-based catalysts. Chemical additives used for this study will include S, P, Ag, Cu, Mn, and Na which have different electronegativities. The effect of additives on the surface state of the catalysts, heat of adsorption of reactant molecules, reaction intermediates, reaction pathways, reaction kinetics, and product distributions is/will be investigated by a series of experimental studies including temperature programmed desorption, infrared study of NO adsorption, reactive probing, steady state rate measurement, and transient kinetic study. A better understanding of the role of additive on the synthesis reaction may allow us to use chemical additives to manipulate the catalytic properties of Rh- and Ni-based catalysts for producing high yields of ethanol from syngas.

  1. The effect of chemical additives on the synthesis of ethanol

    SciTech Connect

    Chuang, S.S.C.

    1990-07-01

    The objective of this research is to elucidate the role of various chemical additives on ethanol synthesis over Rh- and Ni-based catalysts. Chemical additives used for this study will include S, P, Ag, Cu, Mn, and Na which have different electronegativities. The effect of additives on the surface state of the catalysts, heat of adsorption of reactant molecules, reaction intermediates, reaction pathways, reaction kinetics, and product distributions is/will be investigated by a series of experimental studies of NO adsorption, reaction probing, study state rate measurement, and transient kinetic study. A better understanding of the role of additive on the synthesis reaction may allow us to sue chemical additives to manipulate the catalytic properties of Rh- and Ni-based catalysts for producing high yields of ethanol from syngas. (VC)

  2. A review of selected chemical additives in cosmetic products.

    PubMed

    Juhász, Margit Lai Wun; Marmur, Ellen S

    2014-01-01

    The addition of chemical additives to consumer cosmetic products is a common practice to increase cosmetic effectiveness, maintain cosmetic efficacy, and produce a longer-lasting, more viable product. Recently, manufacturers have come under attack for the addition of chemicals including dioxane, formaldehyde, lead/lead acetate, parabens, and phthalate, as these additives may prove harmful to consumer health. Although reports show that these products may indeed adversely affect human health, these studies are conducted using levels of the aforementioned chemicals at much higher levels of exposure than those found in cosmetic products. When cosmeceuticals are used as per manufacturer's instructions, it is estimated that the levels of harmful additives found in these products are considerably lower than reported toxic concentrations.

  3. The effect of chemical additives on the synthesis of ethanol

    SciTech Connect

    Chuang, S.S.C.

    1990-11-01

    The objective of this research is to elucidate the role of additives on the ethanol synthesis over Rh- and Ni-based catalysts. Chemical additives used for this study will include S, P, Ag, Cu, Mn, and Na which have different electronegativities. The effect of additives on the surface state of the catalysts, heat of adsorption of reactant molecules, reaction intermediates, reaction pathways, reaction kinetics, and product distributions is/will be investigated by a series of experimental studies of NO adsorption, reaction probing, study state rate measurement, and transient kinetic study. A better understanding of the role of additive on the synthesis reaction may allow them to use chemical additives to manipulate the catalytic properties of Rh- and Ni-based catalysts for producing high yields of ethanol from syngas. 49 refs., 6 figs., 3 tabs.

  4. Disclosure of hydraulic fracturing fluid chemical additives: analysis of regulations.

    PubMed

    Maule, Alexis L; Makey, Colleen M; Benson, Eugene B; Burrows, Isaac J; Scammell, Madeleine K

    2013-01-01

    Hydraulic fracturing is used to extract natural gas from shale formations. The process involves injecting into the ground fracturing fluids that contain thousands of gallons of chemical additives. Companies are not mandated by federal regulations to disclose the identities or quantities of chemicals used during hydraulic fracturing operations on private or public lands. States have begun to regulate hydraulic fracturing fluids by mandating chemical disclosure. These laws have shortcomings including nondisclosure of proprietary or "trade secret" mixtures, insufficient penalties for reporting inaccurate or incomplete information, and timelines that allow for after-the-fact reporting. These limitations leave lawmakers, regulators, public safety officers, and the public uninformed and ill-prepared to anticipate and respond to possible environmental and human health hazards associated with hydraulic fracturing fluids. We explore hydraulic fracturing exemptions from federal regulations, as well as current and future efforts to mandate chemical disclosure at the federal and state level.

  5. Disclosure of hydraulic fracturing fluid chemical additives: analysis of regulations.

    PubMed

    Maule, Alexis L; Makey, Colleen M; Benson, Eugene B; Burrows, Isaac J; Scammell, Madeleine K

    2013-01-01

    Hydraulic fracturing is used to extract natural gas from shale formations. The process involves injecting into the ground fracturing fluids that contain thousands of gallons of chemical additives. Companies are not mandated by federal regulations to disclose the identities or quantities of chemicals used during hydraulic fracturing operations on private or public lands. States have begun to regulate hydraulic fracturing fluids by mandating chemical disclosure. These laws have shortcomings including nondisclosure of proprietary or "trade secret" mixtures, insufficient penalties for reporting inaccurate or incomplete information, and timelines that allow for after-the-fact reporting. These limitations leave lawmakers, regulators, public safety officers, and the public uninformed and ill-prepared to anticipate and respond to possible environmental and human health hazards associated with hydraulic fracturing fluids. We explore hydraulic fracturing exemptions from federal regulations, as well as current and future efforts to mandate chemical disclosure at the federal and state level. PMID:23552653

  6. A new approach to NMR chemical shift additivity parameters using simultaneous linear equation method.

    PubMed

    Shahab, Yosif A; Khalil, Rabah A

    2006-10-01

    A new approach to NMR chemical shift additivity parameters using simultaneous linear equation method has been introduced. Three general nitrogen-15 NMR chemical shift additivity parameters with physical significance for aliphatic amines in methanol and cyclohexane and their hydrochlorides in methanol have been derived. A characteristic feature of these additivity parameters is the individual equation can be applied to both open-chain and rigid systems. The factors that influence the (15)N chemical shift of these substances have been determined. A new method for evaluating conformational equilibria at nitrogen in these compounds using the derived additivity parameters has been developed. Conformational analyses of these substances have been worked out. In general, the results indicate that there are four factors affecting the (15)N chemical shift of aliphatic amines; paramagnetic term (p-character), lone pair-proton interactions, proton-proton interactions, symmetry of alkyl substituents and molecular association.

  7. The effect of chemical additives on the synthesis of ethanol

    SciTech Connect

    Chuang, S.S.C.

    1989-02-04

    The objective of this research is to elucidate the role of various chemical additives on ethanol synthesis over Rh- and Ni-based catalysts. Chemical additives used will include S, P, Ag, Cu, Mn, and Na. The effect of additives on the surface state of the catalysts, heat of adsorption of reactant molecules, reaction intermediates, reaction pathways, reaction kinetics, and product distributions is/will be investigated by a series of studies including temperature programmed desorption, infrared study of NO adsorption, reactive probing, steady state rate measurement, and transient kinetic study. A better understanding of the role of additive may allow us to use chemical additives to manipulate the catalytic properties of Rh- and Ni-based catalysts for producing high yields of ethanol from syngas. CO insertion is known to be a key step to the formation of acetaldehyde and ethanol from CO hydrogenation over Rh catalysts. Ethylene hydroformylation has often served as a probe to determine CO insertion capabilities of Rh catalysts. The mechanism of CO insertion in ethylene hydroformylation over Rh/SiO{sub 2} was investigated.

  8. Downhole chemical addition owing to convection in annular liquid

    SciTech Connect

    Babu, D.R.; Dhodapkar, P.K.; Pradhan, S.P.; Sharma, A.N.

    1994-03-01

    Production of waxy crude oils normally is associated with such operational problems as wax deposition in the tubulars and gelling of flowlines. Different methods are available to control wax deposition. Continuous addition of certain chemicals at low dosages to the well is popular because it reduces oil viscosity and other downstream problems. These chemicals, known as pour-point depressants (PPD's), remain in semisolid state at ambient temperatures. During winter, the chemical solution needs more expensive solvents or heating to maintain its fluidity. To avoid the costs involved in the surface setup and its maintenance and monitoring, the authors tried a simple method in a few pumping wells with satisfactory results. In this method, the oil column in the casing above the pump suction depth is replaced with a chemical solution. Density of the solution is maintained below that of the produced liquid. This prevents gravity swapping and ensures the presence of a chemical reservoir within the wellbore. When the pump is in operation, the temperature of the tubing's outer surface is a few degrees higher than that of the casing's inner surface. Natural convection currents occur in the liquid trapped between the two surfaces. The liquid rises along the tubing and moves in the opposite direction near the casing. Near the pump suction level, a constant exchange of mass between the crude entering the pump and the chemical reservoir takes place.

  9. Chemical Analyses of Pre-Holocene Rocks from Medicine Lake Volcano and Vicinity, Northern California

    USGS Publications Warehouse

    Donnelly-Nolan, Julie M.

    2008-01-01

    Chemical analyses are presented in an accompanying table (Table 1) for more than 600 pre-Holocene rocks collected at and near Medicine Lake Volcano, northern California. The data include major-element X-ray fluorescence (XRF) analyses for all of the rocks plus XRF trace element data for most samples, and instrumental neutron activation analysis (INAA) trace element data for many samples. In addition, a limited number of analyses of Na2O and K2O by flame photometry (FP) are included as well assome wet chemical analyses of FeO, H2O+/-, and CO2. Latitude and longitude location information is provided for all samples. This data set is intended to accompany the geologic map of Medicine Lake Volcano (Donnelly-Nolan, in press); map unit designations are given for each sample collected from the map area.

  10. Additives initiate selective production of chemicals from biomass pyrolysis.

    PubMed

    Leng, Shuai; Wang, Xinde; Wang, Lei; Qiu, Huizhe; Zhuang, Guilin; Zhong, Xing; Wang, Jianguo; Ma, Fengyun; Liu, Jingmei; Wang, Qiang

    2014-03-01

    To improve chemicals selectivity under low temperature, a new method that involves the injection of additives into biomass pyrolysis is introduced. This method allows biomass pyrolysis to achieve high selectivity to chemicals under low temperature (300°C), while nothing was obtained in typical pyrolysis under 300°C. However, by using the new method, the first liquid drop emerged at the interval between 140°C and 240°C. Adding methanol to mushroom scrap pyrolysis obtained high selectivity to acetic acid (98.33%), while adding ethyl acetate gained selectivity to methanol (65.77%) in bagasse pyrolysis and to acetone (72.51%) in corncob pyrolysis. Apart from basic chemicals, one high value-added chemical (2,3-dihydrobenzofuran) was also detected, which obtained the highest selectivity (10.33%) in corncob pyrolysis through the addition of ethyl acetate. Comparison of HZSM-5 and CaCO3 catalysis showed that benzene emerged in the liquid because of the larger degree of cracking and hydrodeoxygenation over HZSM-5. PMID:24508091

  11. Additives initiate selective production of chemicals from biomass pyrolysis.

    PubMed

    Leng, Shuai; Wang, Xinde; Wang, Lei; Qiu, Huizhe; Zhuang, Guilin; Zhong, Xing; Wang, Jianguo; Ma, Fengyun; Liu, Jingmei; Wang, Qiang

    2014-03-01

    To improve chemicals selectivity under low temperature, a new method that involves the injection of additives into biomass pyrolysis is introduced. This method allows biomass pyrolysis to achieve high selectivity to chemicals under low temperature (300°C), while nothing was obtained in typical pyrolysis under 300°C. However, by using the new method, the first liquid drop emerged at the interval between 140°C and 240°C. Adding methanol to mushroom scrap pyrolysis obtained high selectivity to acetic acid (98.33%), while adding ethyl acetate gained selectivity to methanol (65.77%) in bagasse pyrolysis and to acetone (72.51%) in corncob pyrolysis. Apart from basic chemicals, one high value-added chemical (2,3-dihydrobenzofuran) was also detected, which obtained the highest selectivity (10.33%) in corncob pyrolysis through the addition of ethyl acetate. Comparison of HZSM-5 and CaCO3 catalysis showed that benzene emerged in the liquid because of the larger degree of cracking and hydrodeoxygenation over HZSM-5.

  12. Chemical and structural analyses of titanium plates retrieved from patients.

    PubMed

    Pinto, C M S A; Asprino, L; de Moraes, M

    2015-08-01

    The aim of this study was to evaluate the microscopic structure and chemical composition of titanium bone plates and screws retrieved from patients with a clinical indication and to relate the results to the clinical conditions associated with the removal of these devices. Osteosynthesis plates and screws retrieved from 30 patients between January 2010 and September 2013 were studied by metallographic, gas, and energy dispersive X-ray (EDX) analyses and the medical records of these patients were reviewed. Forty-eight plates and 238 screws were retrieved. The time elapsed between plate and screw insertion and removal ranged between 11 days and 10 years. Metallographic analysis revealed that all the plates were manufactured from commercially pure titanium (CP-Ti). The screw samples analyzed consisted of Ti-6Al-4V alloy, except four samples, which consisted of CP-Ti. Titanium plates studied by EDX analysis presented greater than 99.7% titanium by mass. On gas analysis of Ti-6Al-4V screws, three samples were outside the standard values. One CP-Ti screw sample and one plate sample also presented an oxygen analysis value above the standard. The results indicated that the physical properties and chemical compositions of the plates and screws did not correspond with the need to remove these devices or the time of retention.

  13. Automated determination of chemical functionalisation addition routes based on magnetic susceptibility and nucleus independent chemical shifts

    NASA Astrophysics Data System (ADS)

    Van Lier, G.; Ewels, C. P.; Geerlings, P.

    2008-07-01

    We present a modified version of our previously reported meta-code SACHA, for systematic analysis of chemical addition. The code automates the generation of structures, running of quantum chemical codes, and selection of preferential isomers based on chosen selection rules. While the selection rules for the previous version were based on the total system energy, predicting purely thermodynamic addition patterns, we examine here the possibility of using other system parameters, notably magnetic susceptibility as a descriptor of global aromaticity, and nucleus independent chemical shifts (NICS) as local aromaticity descriptor.

  14. Additives

    NASA Technical Reports Server (NTRS)

    Smalheer, C. V.

    1973-01-01

    The chemistry of lubricant additives is discussed to show what the additives are chemically and what functions they perform in the lubrication of various kinds of equipment. Current theories regarding the mode of action of lubricant additives are presented. The additive groups discussed include the following: (1) detergents and dispersants, (2) corrosion inhibitors, (3) antioxidants, (4) viscosity index improvers, (5) pour point depressants, and (6) antifouling agents.

  15. The effect of chemical additives on the synthesis of ethanol

    SciTech Connect

    Chuang, S.S.C.; Pien, S.I.

    1991-06-01

    The objective of this research is to elucidate the role of various chemical additives on ethanol synthesis over Rh- and Ni-based catalysts. Chemical additives used for this study will include S, P, Ag, Cu, Mn, and Na which have different electronegativeities. The effect of additives on the surface state of the catalysts, heat of adsorption of reactant molecules, reaction intermediates, reaction pathways, reaction kinetics, and product distributions is/will be investigated by a series of experimental studies of NO adsorption, reactive probing, steady state rate measurement, and transient kinetic study. CO insertion is known to be a key step to the formation of acetaldehyde and ethanol from CO hydrogenation. Reaction of ethylene with syngas is used as a probe to determine CO insertion capabilities of metal catalysts. During the sixth quarter of the project, the mechanism of CO insertion on Ni/SiO{sub 2} was investigated by in-situ infrared spectroscopy. Ni/SiO{sub 2}, a methanation catalyst, has been shown to exhibit CO insertion activity. In situ infrared studies of CO/H{sub 2} and C{sub 2}H{sub 4}/CO/H{sub 2} reactions show that the carbonylation of Ni/SiO{sub 2} to Ni(CO){sub 4} leads to an inhibition of methanation in CO hydrogenation but an enhancement of formation of propionaldehyde in C{sub 2}H{sub 4}/CO/H{sub 2} reaction. The results suggest that the sites for propionaldehyde formation is different from those for methanation.

  16. Chemical analyses in the World Coal Quality Inventory

    USGS Publications Warehouse

    Tewalt, Susan J.; Belkin, Harvey E.; SanFilipo, John R.; Merrill, Matthew D.; Palmer, Curtis A.; Warwick, Peter D.; Karlsen, Alexander W.; Finkelman, Robert B.; Park, Andy J.

    2010-01-01

    The main objective of the World Coal Quality Inventory (WoCQI) was to collect and analyze a global set of samples of mined coal during a time period from about 1995 to 2006 (Finkelman and Lovern, 2001). Coal samples were collected by foreign collaborators and submitted to country specialists in the U.S. Geological Survey (USGS) Energy Program. However, samples from certain countries, such as Afghanistan, India, and Kyrgyzstan, were collected collaboratively in the field with USGS personnel. Samples were subsequently analyzed at two laboratories: the USGS Inorganic Geochemistry Laboratory located in Denver, CO and a commercial laboratory (Geochemical Testing, Inc.) located in Somerset, PA. Thus the dataset, which is in Excel (2003) format and includes 1,580 samples from 57 countries, does not have the inter-laboratory variability that is present in many compilations. Major-, minor-, and trace-element analyses from the USGS laboratory, calculated to a consistent analytical basis (dry, whole-coal) and presented with available sample identification information, are sorted alphabetically by country name. About 70 percent of the samples also have data from the commercial laboratory, which are presented on an as-received analytical basis. The USGS initiated a laboratory review of quality assurance in 2008, covering quality control and methodology used in inorganic chemical analyses of coal, coal power plant ash, water, and sediment samples. This quality control review found that data generated by the USGS Inorganic Geochemistry Laboratory from 1996 through 2006 were characterized by quality practices that did not meet USGS requirements commonly in use at the time. The most serious shortcomings were (1) the adjustment of raw sample data to standards when the instrument values for those standards exceeded acceptable limits or (2) the insufficient use of multiple standards to provide adequate quality assurance. In general, adjustment of raw data to account for instrument

  17. NMR characterization of cellulose acetate: chemical shift assignments, substituent effects, and chemical shift additivity.

    PubMed

    Kono, Hiroyuki; Hashimoto, Hisaho; Shimizu, Yuuichi

    2015-03-15

    A series of cellulose acetates (CA) with degrees of substitution (DS) ranging from 2.92-0.92 dissolved in dimethylsulfoxide (DMSO)-d6 and cellulose dissolved in tetrabutylammonium fluoride (TBAF)/DMSO-d6 were investigated by two-dimensional NMR spectroscopy. The NMR spectroscopic analysis allowed the determination of the (1)H and (13)C NMR chemical shifts of the eight anhydroglucose units (AGUs) that contain CA: 2,3,6-tri-, 2,3-di-, 2,6-di-, 3,6-di-, 2-mono-, 3-mono-, 6-mono-, and unacetylated AGUs. A comparative analysis of the chemical shift data revealed the substituent effect of acetyl groups at the 2-, 3-, and 6-positions on the (1)H and (13)C nuclei in the same AGU. In addition, chemical shift additivity could be applied to the (1)H and (13)C chemical shifts of CA because the chemical shifts of the diacetylated and triacetylated AGUs could be almost completely explained by the acetyl substituent effects at the 2-, 3-, and 6-positions.

  18. Proteomic analyses of the environmental toxicity of carcinogenic chemicals

    EPA Science Inventory

    Protein expression and posttranslational modifications consistently change in response to the exposure to environmental chemicals. Recent technological advances in proteomics provide new tools for more efficient characterization of protein expression and posttranslational modific...

  19. Hematite Surface Activation by Chemical Addition of Tin Oxide Layer.

    PubMed

    Carvalho, Waldemir M; Souza, Flavio L

    2016-09-01

    In this study, the effect of tin (Sn(4+) ) modification on the surface of hematite electrodes synthesized by an aqueous solution route at different times (2, 5, 10, 18, and 24 h) is investigated. As confirmed from X-ray diffraction results, the as-synthesized electrode exhibits an oxyhydroxide phase, which is converted into a pure hematite phase after being subjected to additional thermal treatment at 750 °C for 30 min. The tin-modified hematite electrode is prepared by depositing a solution of Sn(4+) precursor on the as-synthesized electrode, followed by thermal treatment under the same abovementioned conditions. This modification results in an enhancement of the photocurrent response for all hematite electrodes investigated and attains the highest values of around 1.62 and 2.3 mA cm(-2) at 1.23 and 1.4 V versus RHE, respectively, for electrodes obtained in short synthesis times (2 h). Contact angle measurements suggest that the deposition of Sn(4+) on the hematite electrode provides a more hydrophilic surface, which favors a chemical reaction at the interface between the electrode and electrolyte. This result generates new perspectives for understanding the deposition of Sn(4+) on the hematite electrode surface, which is in contrast with several studies previously reported; these studies state that the enhancement in photocurrent density is related to either the induction of an increased donor charge density or shift in the flat-band potential, which favors charge separation.

  20. Chemical analyses of surface waters in Oklahoma, September - December, 1944

    USGS Publications Warehouse

    U.S. Geological Survey

    1945-01-01

    Red River at Denison Dam, Texas Sport samples were collected at the remainder of the stations. The analyses of the spot samples were made largely in a laboratory provided by the Oklahoma A. & M. College, under the supervision of Dr. O.M. Smith, Head, Department of Chemistry; Dr. S.R. Wood, Associate Professor of Chemistry; and W.W. Hastings, U.S. Geological Survey. The daily samples were analyzed in the water resources laboratory of the Geological Survey at Austin, Texas. These data have been summarized in a report to the Oklahoma Planning and Resources Board prepared by the U.S. Geological Survey, March 1, 1945. The streams of Oklahoma are classified into two major drainage basins: the Arkansas River and the Red River and their tributaries. The attached analyses are arranged in geographical order for their respective drainage basins, with records listed in downstream order for stations on the main stem first, followed by the analyses for the tributaries. When available, the mean daily discharge is given for the analyses.

  1. Toxicity and chemical analyses of airport runoff waters in Poland.

    PubMed

    Sulej, Anna Maria; Polkowska, Zaneta; Wolska, Lidia; Cieszynska, Monika; Namieśnik, Jacek

    2014-05-01

    The aim of this study was to assess the ecotoxicological effects of various compounds in complex airport effluents using a chemical and ecotoxicological integrated strategy. The present work deals with the determination of sum of PCBs, PAHs, pesticides, cations, anions, phenols, anionic, cationic, non-ionic detergents, formaldehyde and metals--as well as TOC and conductivity--in runoff water samples collected from 2009 to 2011 at several locations on two Polish international airports. Two microbiotests (Vibrio fischeri bacteria and the crustacean Thamnocephalus platyurus) have been used to determine the ecotoxicity of airport runoff waters. The levels of many compounds exceeded several or even several tens of times the maximum permissible levels. Analysis of the obtained data shows that samples that displayed maximum toxicity towards the bioindicators Vibrio fischeri were not toxic towards Thamnocephalus platyurus. Levels of toxicity towards T. platyurus are strongly correlated with pollutants that originate from the technological operations related to the maintenance of airport infrastructure. The integrated (chemical-ecotoxicological) approach to environmental contamination assessment in and around airports yields extensive information on the quality of the environment. These methodologies can be then used as tools for tracking the environmental fate of these compounds and for assessing the environmental effect of airports. Subsequently, these data will provide a basis for airport infrastructure management. PMID:24668023

  2. Toxicity and chemical analyses of airport runoff waters in Poland.

    PubMed

    Sulej, Anna Maria; Polkowska, Zaneta; Wolska, Lidia; Cieszynska, Monika; Namieśnik, Jacek

    2014-05-01

    The aim of this study was to assess the ecotoxicological effects of various compounds in complex airport effluents using a chemical and ecotoxicological integrated strategy. The present work deals with the determination of sum of PCBs, PAHs, pesticides, cations, anions, phenols, anionic, cationic, non-ionic detergents, formaldehyde and metals--as well as TOC and conductivity--in runoff water samples collected from 2009 to 2011 at several locations on two Polish international airports. Two microbiotests (Vibrio fischeri bacteria and the crustacean Thamnocephalus platyurus) have been used to determine the ecotoxicity of airport runoff waters. The levels of many compounds exceeded several or even several tens of times the maximum permissible levels. Analysis of the obtained data shows that samples that displayed maximum toxicity towards the bioindicators Vibrio fischeri were not toxic towards Thamnocephalus platyurus. Levels of toxicity towards T. platyurus are strongly correlated with pollutants that originate from the technological operations related to the maintenance of airport infrastructure. The integrated (chemical-ecotoxicological) approach to environmental contamination assessment in and around airports yields extensive information on the quality of the environment. These methodologies can be then used as tools for tracking the environmental fate of these compounds and for assessing the environmental effect of airports. Subsequently, these data will provide a basis for airport infrastructure management.

  3. Lipids: From Chemical Structures, Biosynthesis, and Analyses to Industrial Applications.

    PubMed

    Li-Beisson, Yonghua; Nakamura, Yuki; Harwood, John

    2016-01-01

    Lipids are one of the major subcellular components, and play numerous essential functions. As well as their physiological roles, oils stored in biomass are useful commodities for a variety of biotechnological applications including food, chemical feedstocks, and fuel. Due to their agronomic as well as economic and societal importance, lipids have historically been subjected to intensive studies. Major current efforts are to increase the energy density of cell biomass, and/or create designer oils suitable for specific applications. This chapter covers some basic aspects of what one needs to know about lipids: definition, structure, function, metabolism and focus is also given on the development of modern lipid analytical tools and major current engineering approaches for biotechnological applications. This introductory chapter is intended to serve as a primer for all subsequent chapters in this book outlining current development in specific areas of lipids and their metabolism. PMID:27023229

  4. Computational Analyses of Complex Flows with Chemical Reactions

    NASA Astrophysics Data System (ADS)

    Bae, Kang-Sik

    The heat and mass transfer phenomena in micro-scale for the mass transfer phenomena on drug in cylindrical matrix system, the simulation of oxygen/drug diffusion in a three dimensional capillary network, and a reduced chemical kinetic modeling of gas turbine combustion for Jet propellant-10 have been studied numerically. For the numerical analysis of the mass transfer phenomena on drug in cylindrical matrix system, the governing equations are derived from the cylindrical matrix systems, Krogh cylinder model, which modeling system is comprised of a capillary to a surrounding cylinder tissue along with the arterial distance to veins. ADI (Alternative Direction Implicit) scheme and Thomas algorithm are applied to solve the nonlinear partial differential equations (PDEs). This study shows that the important factors which have an effect on the drug penetration depth to the tissue are the mass diffusivity and the consumption of relevant species during the time allowed for diffusion to the brain tissue. Also, a computational fluid dynamics (CFD) model has been developed to simulate the blood flow and oxygen/drug diffusion in a three dimensional capillary network, which are satisfied in the physiological range of a typical capillary. A three dimensional geometry has been constructed to replicate the one studied by Secomb et al. (2000), and the computational framework features a non-Newtonian viscosity model for blood, the oxygen transport model including in oxygen-hemoglobin dissociation and wall flux due to tissue absorption, as well as an ability to study the diffusion of drugs and other materials in the capillary streams. Finally, a chemical kinetic mechanism of JP-10 has been compiled and validated for a wide range of combustion regimes, covering pressures of 1atm to 40atm with temperature ranges of 1,200 K--1,700 K, which is being studied as a possible Jet propellant for the Pulse Detonation Engine (PDE) and other high-speed flight applications such as hypersonic

  5. Toxicity testing and chemical analyses of recycled fibre-based paper for food contact.

    PubMed

    Binderup, M L; Pedersen, G A; Vinggaard, A M; Rasmussen, E S; Rosenquist, H; Cederberg, T

    2002-01-01

    hydrocarbon (Ah)-receptor assay (CALUX assay) as a screening test for compounds with dioxin-like activity. In addition, the papers were testedfor microbial content and, in general, the microbiological load was quite low. The following microorganisms were counted and identified on both surface and homogenized pulp samples: the total number of aerobic bacteria, the number of aerobic and anaerobic spore formers, the number of Bacillus cereus/thuringiensis, and the number of yeast and moulds. The chemical analyses showed a significantly higher amount and different composition pattern of chemicals extracted with ethanol compared with water. Analyses of the ethanol extracts showed a distinctly smaller number and lower concentrations of chemicals in extracts prepared from sample A compared with extracts of samples B-D. The compounds identified in B-D were similar, but the amounts were lower in B compared with C and D. In accordance with the chemical analyses, the water extracts were less cytotoxic than the ethanol extracts. The extract prepared from virgin fibres was less cytotoxic than the extracts prepared from paper made from recycled fibres, and extracts prepared from C was the most cytotoxic. None of the extracts showed mutagenic activity. No conclusion about the oestrogenic activity could be made, because all extracts were cytotoxic to the test organism (yeast cells). Ethanol extracts of A and B showed a negligible positive response in the Ah-receptor assay at the highest nontoxic concentration, whereas C and D showed a more pronounced effect with C being the most potent. A comparable weak effect of water extracts of samples B-D was observed, too. However, the active compound(s) was not identified by chemical analyses. PMID:11962701

  6. 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

  7. Diatremes of the Hopi Buttes, Arizona; chemical and statistical analyses

    USGS Publications Warehouse

    Wenrich, K.J.; Mascarenas, J.F.

    1982-01-01

    Lacustrine sediments deposited in maar lakes of the Hopi Buttes diatremes are hosts for uranium mineralization of as much as 1500 ppm. The monchiquites and limburgite turfs erupted from the diatremes are distinguished from normal alkalic basalts of the Colorado Plateau by their extreme silica undersaturation and high water, TiO2, and P2O5 contents. Many trace elements are also unusually abundant, including Ag, As, Ba, Be, Ce, Dy, Eu, F, Gd, Hf, La, Nd, Pb, Rb, Se, Sm, Sn, Sr, Ta, Tb, Th, U, V, Zn, and Zr. The lacustrine sediments, which consist predominantly of travertine and clastic rocks, are the hosts for syngenetic and epigenetic uranium mineralization of as much as 1500 ppm uranium. Fission track maps show the uranium to be disseminated within the travertine and clastic rocks, and although microprobe analyses have not, as yet, revealed discrete uranium-bearing phases, the clastic rocks show a correlation of high Fe, Ti, and P with areas of high U. Correlation coefficients show that for the travertines, clastics, and limburgite ruffs, Mo, As, Sr, Co, and V appear to have the most consistent and strongest correlations with uranium. Many elements, including many of the rare-earth elements, that are high in these three rocks are also high in the monchiquites, as compared to the average crustal abundance for the respective rock type. This similar suite of anomalous elements, which includes such immobile elements as the rare earths, suggests that Fluids which deposited the travertines were related to the monchiquitic magma. The similar age of about 5 m.y. for both the lake beds and the monchiquites also appears to support this source for the mineralizing fluids.

  8. ADDITIONAL STRESS AND FRACTURE MECHANICS ANALYSES OF PRESSURIZED WATER REACTOR PRESSURE VESSEL NOZZLES

    SciTech Connect

    Walter, Matthew; Yin, Shengjun; Stevens, Gary; Sommerville, Daniel; Palm, Nathan; Heinecke, Carol

    2012-01-01

    In past years, the authors have undertaken various studies of nozzles in both boiling water reactors (BWRs) and pressurized water reactors (PWRs) located in the reactor pressure vessel (RPV) adjacent to the core beltline region. Those studies described stress and fracture mechanics analyses performed to assess various RPV nozzle geometries, which were selected based on their proximity to the core beltline region, i.e., those nozzle configurations that are located close enough to the core region such that they may receive sufficient fluence prior to end-of-life (EOL) to require evaluation of embrittlement as part of the RPV analyses associated with pressure-temperature (P-T) limits. In this paper, additional stress and fracture analyses are summarized that were performed for additional PWR nozzles with the following objectives: To expand the population of PWR nozzle configurations evaluated, which was limited in the previous work to just two nozzles (one inlet and one outlet nozzle). To model and understand differences in stress results obtained for an internal pressure load case using a two-dimensional (2-D) axi-symmetric finite element model (FEM) vs. a three-dimensional (3-D) FEM for these PWR nozzles. In particular, the ovalization (stress concentration) effect of two intersecting cylinders, which is typical of RPV nozzle configurations, was investigated. To investigate the applicability of previously recommended linear elastic fracture mechanics (LEFM) hand solutions for calculating the Mode I stress intensity factor for a postulated nozzle corner crack for pressure loading for these PWR nozzles. These analyses were performed to further expand earlier work completed to support potential revision and refinement of Title 10 to the U.S. Code of Federal Regulations (CFR), Part 50, Appendix G, Fracture Toughness Requirements, and are intended to supplement similar evaluation of nozzles presented at the 2008, 2009, and 2011 Pressure Vessels and Piping (PVP

  9. Additional Measurements and Analyses of H217O and H218O

    NASA Astrophysics Data System (ADS)

    Pearson, John; Yu, Shanshan; Walters, Adam; Daly, Adam M.

    2015-06-01

    Historically the analysis of the spectrum of water has been a balance between the quality of the data set and the applicability of the Hamiltonian to a highly non-rigid molecule. Recently, a number of different non-rigid analysis approaches have successfully been applied to 16O water resulting in a self-consistent set of transitions and energy levels to high J which allowed the spectrum to be modeled to experimental precision. The data set for 17O and 18O water was previously reviewed and many of the problematic measurements identified, but Hamiltonian modeling of the remaining data resulted in significantly poorer quality fits than that for the 16O parent. As a result, we have made additional microwave measurements and modeled the existing 17O and 18O data sets with an Euler series model. This effort has illuminated a number of additional problematic measurements in the previous data sets and has resulted in analyses of 17O and 18O water that are of similar quality to the 16O analysis. We report the new lines, the analyses and make recommendations on the quality of the experimental data sets. SS. Yu, J.C. Pearson, B.J. Drouin et al. J. Mol. Spectrosc. 279,~16-25 (2012) J. Tennyson, P.F. Bernath, L.R. Brown et al. J. Quant. Spectrosc. Rad. Trans. 117, 29-58 (2013) J. Tennyson, P.F. Bernath, L.R. Brown et al. J. Quant. Spectrosc. Rad. Trans. 110, 573-596 (2009) H.M. Pickett, J.C. Pearson, C.E. Miller J. Mol. Spectrosc. 233, 174-179 (2005)

  10. The effect of chemical additives on the synthesis of ethanol

    SciTech Connect

    Chuang, S.S.C.

    1992-03-06

    The objective of this research was to investigate the reaction mechanism of higher alcohol and aldehyde synthesis from syngas and the role of additives in the synthesis. An in situ IR reaction system and probe molecule technique were developed to study adsorbed species, active sites, and reaction pathway during reaction. The catalysts used for this study included silica-supported Rh, Ru, and Ni. (VC)

  11. Bioavailability of chemical pollutants in contaminated soils and pitfalls of chemical analyses in hazard assessment.

    PubMed

    Vasseur, P; Bonnard, M; Palais, F; Eom, I C; Morel, J L

    2008-10-01

    Decision-making for remediation of industrial wastelands are still based on the concentrations of pollutants of concern measured in soils. In this work, two soils polluted by polycyclic aromatic hydrocarbons (PAHs) and metals were investigated for their toxicity on earthworms (Eisenia fetida), collembolae (Folsomia candida), and higher plants (Brassica chinensis, Lactucca sativa and Avena sativa) in order to study the relationships between chemical contamination and biological effects. Although the level of contamination by PAHs was elevated and commensurate in the two soils, their toxicity profile was quite different. Soil A affected survival and reproduction of invertebrates and growth of higher plants. Surprisingly, soil B, heavily contaminated by metals in addition to PAHs, was devoid of toxicity. Our results indicate that toxicity cannot simply be extrapolated from pollutant concentrations in a complex matrix in which bioavailability of pollutants may be reduced by ageing. Moreover, the use of toxicity data obtained from spiked soils characterized by readily bioavailable pollutants can also be called into question for such extrapolations. Predicting biological effects therefore requires biological tools to avoid any erroneous conclusions that can be drawn from sole extrapolation of analytical results.

  12. Chemical and spectroscopic analyses of organic matter transformation in warming tundra soils

    NASA Astrophysics Data System (ADS)

    Herndon, E.; Roy Chowdhury, T.; Mann, B. F.; Graham, D. E.; Bargar, J.; Gu, B.; Liang, L.

    2013-12-01

    with increasing mineral content of the soil, likely due to the presence of labile organics bound to Fe-oxide minerals. In addition, 13-80% of the total C remained in soil following sequential chemical extractions, suggesting resistance to degradation and strong association with minerals. Soil incubations showed temperature-dependent production of CO2 and CH4, indicating microbial C degradation. The masses of CO2 and CH4 released represent only a small fraction of the total soil organic C, and little change in was observed in bulk SOM. However, the water-soluble C exhibited significant vulnerability to degradation, as revealed by HPLC and spectroscopic analyses, and these results suggest potential pathways for chemical transformation of soil C during decomposition. The results of this study will contribute to a computational modeling framework for understanding sources and rates of C fluxes from soils to the atmosphere and will help elucidate potential changes to Arctic tundra systems subject to warming.

  13. Effects of xanthan, guar, carrageenan and locust bean gum addition on physical, chemical and sensory properties of meatballs.

    PubMed

    Demirci, Zeynep Ozben; Yılmaz, Ismail; Demirci, Ahmet Şukru

    2014-05-01

    This study evaluated the effects of xanthan gum, guar gum, carrageenan and locust bean gum on physical, chemical and sensory properties of meatballs. Meatball samples were produced with three different formulations including of 0.5, 1, and 1.5% each gum addition and gum added samples were compared with the control meatballs. Physical and chemical analyses were carried out on raw and cooked samples separately. Moisture contents of raw samples decreased by addition of gums. There were significant decreases (p < 0.05) in moisture and fat contents of raw and cooked meatball samples formulated with gum when compared with control. Ash contents and texture values increased with gum addition to meatballs. Meatball redness decreased with more gum addition in raw and cooked meatball samples, which means that addition of gums resulted in a lighter-coloured product. According to sensory analysis results, locust bean gum added (1%) samples were much preferred by the panelists.

  14. Effects of xanthan, guar, carrageenan and locust bean gum addition on physical, chemical and sensory properties of meatballs.

    PubMed

    Demirci, Zeynep Ozben; Yılmaz, Ismail; Demirci, Ahmet Şukru

    2014-05-01

    This study evaluated the effects of xanthan gum, guar gum, carrageenan and locust bean gum on physical, chemical and sensory properties of meatballs. Meatball samples were produced with three different formulations including of 0.5, 1, and 1.5% each gum addition and gum added samples were compared with the control meatballs. Physical and chemical analyses were carried out on raw and cooked samples separately. Moisture contents of raw samples decreased by addition of gums. There were significant decreases (p < 0.05) in moisture and fat contents of raw and cooked meatball samples formulated with gum when compared with control. Ash contents and texture values increased with gum addition to meatballs. Meatball redness decreased with more gum addition in raw and cooked meatball samples, which means that addition of gums resulted in a lighter-coloured product. According to sensory analysis results, locust bean gum added (1%) samples were much preferred by the panelists. PMID:24803701

  15. 15 CFR 714.3 - Advance declaration requirements for additionally planned production of Schedule 3 chemicals.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... additionally planned production of Schedule 3 chemicals. 714.3 Section 714.3 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) BUREAU OF INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING SCHEDULE 3 CHEMICALS § 714.3...

  16. 15 CFR 714.3 - Advance declaration requirements for additionally planned production of Schedule 3 chemicals.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... additionally planned production of Schedule 3 chemicals. 714.3 Section 714.3 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) BUREAU OF INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING SCHEDULE 3 CHEMICALS § 714.3...

  17. 15 CFR 714.3 - Advance declaration requirements for additionally planned production of Schedule 3 chemicals.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... additionally planned production of Schedule 3 chemicals. 714.3 Section 714.3 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) BUREAU OF INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING SCHEDULE 3 CHEMICALS § 714.3...

  18. 15 CFR 714.3 - Advance declaration requirements for additionally planned production of Schedule 3 chemicals.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... additionally planned production of Schedule 3 chemicals. 714.3 Section 714.3 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) BUREAU OF INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING SCHEDULE 3 CHEMICALS § 714.3...

  19. 15 CFR 714.3 - Advance declaration requirements for additionally planned production of Schedule 3 chemicals.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... additionally planned production of Schedule 3 chemicals. 714.3 Section 714.3 Commerce and Foreign Trade Regulations Relating to Commerce and Foreign Trade (Continued) BUREAU OF INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING SCHEDULE 3 CHEMICALS § 714.3...

  20. Chemical analyses of rocks, minerals, and detritus, Yucca Mountain--Preliminary report, special report No. 11

    SciTech Connect

    Hill, C.A.; Livingston, D.E.

    1993-09-01

    This chemical analysis study is part of the research program of the Yucca Mountain Project intended to provide the State of Nevada with a detailed assessment of the geology and geochemistry of Yucca Mountain and adjacent regions. This report is preliminary in the sense that more chemical analyses may be needed in the future and also in the sense that these chemical analyses should be considered as a small part of a much larger geological data base. The interpretations discussed herein may be modified as that larger data base is examined and established. All of the chemical analyses performed to date are shown in Table 1. There are three parts to this table: (1) trace element analyses on rocks (limestone and tuff) and minerals (calcite/opal), (2) rare earth analyses on rocks (tuff) and minerals (calcite/opal), and (3) major element analyses + CO{sub 2} on rocks (tuff) and detritus sand. In this report, for each of the three parts of the table, the data and its possible significance will be discussed first, then some overall conclusions will be made, and finally some recommendations for future work will be offered.

  1. Effect of GdL Addition on Physico-chemical Properties of Fermented Sausages during Ripening

    PubMed Central

    Yim, Dong-Gyun

    2015-01-01

    This study investigated the effects of glucono-δ-lactone (GdL) addition on physicochemical and microbiological characteristics of fermented sausages during ripening and drying. Five batches of sausages were produced under ripening conditions: without GdL and with 0, 0.1, 0.25, 0.5 and 0.75% of GdL addition. Samples from each treatment were taken for physicochemical and microbiological analyses on the 0, 1, 3, 5, 7, 10, 15, 20 and 25th day of ripening. Chemical analysis showed a significant decrease in moisture content of sausages with increasing amounts of GdL added (p<0.05). The moisture contents decreased, whereas the fat, protein and ash contents increased throughout ripening (p<0.05). Increasing levels of GdL caused a decrease in the pH values (p<0.05), which can have an inhibitory effect against microflora. Water holding capacity content of samples decreased with increasing GdL concentration (p<0.05). The shear force values of fermented sausages showed the highest in T4 (p<0.05). During ripening, the shear force values of sausages were increased on the 25th day compared to day 0 (p<0.05). The higher GdL level produced lighter and more yellow sausages. The addition of 0.75% GdL was effective in controlling bacteria counts. Addition of GdL in sausages resulted in the physicochemical and microbiological attributes equal to or better than no addition of GdL without any harmful effect. PMID:26761846

  2. Using Additional Analyses to Clarify the Functions of Problem Behavior: An Analysis of Two Cases

    ERIC Educational Resources Information Center

    Payne, Steven W.; Dozier, Claudia L.; Neidert, Pamela L.; Jowett, Erica S.; Newquist, Matthew H.

    2014-01-01

    Functional analyses (FA) have proven useful for identifying contingencies that influence problem behavior. Research has shown that some problem behavior may only occur in specific contexts or be influenced by multiple or idiosyncratic variables. When these contexts or sources of influence are not assessed in an FA, further assessment may be…

  3. 49 CFR 107.807 - Approval of non-domestic chemical analyses and tests.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Approval of non-domestic chemical analyses and... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS AND OIL TRANSPORTATION HAZARDOUS MATERIALS PROGRAM PROCEDURES Approval of Independent Inspection Agencies,...

  4. CAES 2014 Chemical Analyses of Thermal Wells and Springs in Southeastern Idaho

    DOE Data Explorer

    Baum, Jeffrey

    2014-03-10

    This dataset contains chemical analyses for thermal wells and springs in Southeastern Idaho. Data includes all major cations, major anions, pH, collection temperature, and some trace metals, These samples were collected in 2014 by the Center for Advanced Energy Studies (CAES), and are part of a continuous effort to analyze the geothermal potential of Southeastern Idaho.

  5. Physico-chemical analyses of Hispano-Moresque lustred ceramic: a precursor for Italian majolica?

    NASA Astrophysics Data System (ADS)

    Chabanne, D.; Bouquillon, A.; Aucouturier, M.; Dectot, X.; Padeletti, G.

    2008-07-01

    The paper presents a comprehensive physico-chemical investigation on a series of Hispano-Moresque objects produced in the eastern Spain workshops between the XIV and XVIII centuries and fragments from XII century, in order to compare them with the Italian Renaissance majolica production. The techniques used are mainly non-destructive (ion beam analyses and X-ray diffraction), sometimes complemented by SEM observation and microanalysis, and electrothermal atomic emission spectrometry. Such methods allow a full description of the terra cotta, of the glaze and of the different surface layers which constitute the lustre decoration indicating individual elemental composition and thickness of each layer containing or not metallic nanoparticles. Principal results show the following: i) a constant source of supply for the eastern Spain terra cotta; ii) a significant change in the composition of the Spanish glazes around the XVII century, with the disappearance of the opacifying tin oxide addition; iii) significant evolutions in the structure and composition of the lustre layers, in particular related to the presence or not of a metal-free surface glaze film and its thickness; iv) interesting analogies and differences with the Italian majolica; v) confirmation of the change in the quality of blue pigment during XVI century, already evidenced by the authors in previous publications. A discussion about the transmission of the lustre technique between eastern Spain and Italy at the Renaissance period is proposed.

  6. Chemical and sensory profiles of makgeolli, Korean commercial rice wine, from descriptive, chemical, and volatile compound analyses.

    PubMed

    Jung, Heeyong; Lee, Seung-Joo; Lim, Jeong Ho; Kim, Bum Keun; Park, Kee Jai

    2014-01-01

    The chemical and sensory profiles of 12 commercial samples of makgeolli, a Korean rice wine, were determined using descriptive sensory, chemical, and volatile components analyses. The sample wines were analysed for their titratable acidity, ethanol content, pH, Hunter colour value and total reducing sugars. The chemical compositions of the makgeolli samples were found to be significantly different. The volatile compounds were extracted with solid-phase microextraction and analysed by gas chromatography time-of-flight mass spectrometry. In all, 45 major volatile compounds, consisting of 33 esters, 8 alcohols, 1 aldehyde, 1 acid, 1 phenol and 1 terpene, were identified; each makgeolli sample included 28-35 volatile compounds. Based on principal component analysis of the sensory data, samples RW1, RW2, RW5, RW8 and RW12 were associated with roasted cereal, mouldy, bubbles, sweet and sour attributes; the other samples were associated with sensory attributes of yellowness, yeast, full body, turbidity, continuation, swallow, alcohol, fruit aroma and whiteness. PMID:24444985

  7. Chemical and sensory profiles of makgeolli, Korean commercial rice wine, from descriptive, chemical, and volatile compound analyses.

    PubMed

    Jung, Heeyong; Lee, Seung-Joo; Lim, Jeong Ho; Kim, Bum Keun; Park, Kee Jai

    2014-01-01

    The chemical and sensory profiles of 12 commercial samples of makgeolli, a Korean rice wine, were determined using descriptive sensory, chemical, and volatile components analyses. The sample wines were analysed for their titratable acidity, ethanol content, pH, Hunter colour value and total reducing sugars. The chemical compositions of the makgeolli samples were found to be significantly different. The volatile compounds were extracted with solid-phase microextraction and analysed by gas chromatography time-of-flight mass spectrometry. In all, 45 major volatile compounds, consisting of 33 esters, 8 alcohols, 1 aldehyde, 1 acid, 1 phenol and 1 terpene, were identified; each makgeolli sample included 28-35 volatile compounds. Based on principal component analysis of the sensory data, samples RW1, RW2, RW5, RW8 and RW12 were associated with roasted cereal, mouldy, bubbles, sweet and sour attributes; the other samples were associated with sensory attributes of yellowness, yeast, full body, turbidity, continuation, swallow, alcohol, fruit aroma and whiteness.

  8. TANK 40 FINAL SB5 CHEMICAL CHARACTERIZATION RESULTS PRIOR TO NP ADDITION

    SciTech Connect

    Bannochie, C.; Click, D.

    2010-01-06

    A sample of Sludge Batch 5 (SB5) was pulled from Tank 40 in order to obtain radionuclide inventory analyses necessary for compliance with the Waste Acceptance Product Specifications (WAPS). This sample was also analyzed for chemical composition including noble metals. Prior to radionuclide inventory analyses, a final sample of the H-canyon Np stream will be added to bound the Np addition anticipated for Tank 40. These analyses along with the WAPS radionuclide analyses will help define the composition of the sludge in Tank 40 that is currently being fed to DWPF as SB5. At the Savannah River National Laboratory (SRNL) the 3-L Tank 40 SB5 sample was transferred from the shipping container into a 4-L high density polyethylene vessel and solids allowed to settle overnight. Supernate was then siphoned off and circulated through the shipping container to complete the transfer of the sample. Following thorough mixing of the 3-L sample, a 239 g sub-sample was removed. This sub-sample was then utilized for all subsequent analytical samples. Eight separate aliquots of the slurry were digested, four with HNO{sub 3}/HCl (aqua regia) in sealed Teflon{reg_sign} vessels and four in Na{sub 2}O{sub 2} (alkali or peroxide fusion) using Zr crucibles. Due to the use of Zr crucibles and Na in the peroxide fusions, Na and Zr cannot be determined from this preparation. Additionally, other alkali metals, such as Li and K that may be contaminants in the Na{sub 2}O{sub 2} are not determined from this preparation. Three Analytical Reference Glass - 14 (ARG-1) standards were digested along with a blank for each preparation. The ARG-1 glass allows for an assessment of the completeness of each digestion. Each aqua regia digestion and blank was diluted to 1:100 mL with deionized water and submitted to Analytical Development (AD) for inductively coupled plasma - atomic emission spectroscopy (ICPAES) analysis, inductively coupled plasma - mass spectrometry (ICP-MS) analysis of masses 81-209 and 230

  9. TANK 40 FINAL SB5 CHEMICAL CHARACTERIZATION RESULTS PRIOR TO NP ADDITION

    SciTech Connect

    Bannochie, C; Damon Click, D

    2009-02-26

    A sample of Sludge Batch 5 (SB5) was pulled from Tank 40 in order to obtain radionuclide inventory analyses necessary for compliance with the Waste Acceptance Product Specifications (WAPS). This sample was also analyzed for chemical composition including noble metals. Prior to radionuclide inventory analyses, a final sample of the H-canyon Np stream will be added to bound the Np addition anticipated for Tank 40. These analyses along with the WAPS radionuclide analyses will help define the composition of the sludge in Tank 40 that is currently being fed to DWPF as SB5. At the Savannah River National Laboratory (SRNL) the 3-L Tank 40 SB5 sample was transferred from the shipping container into a 4-L high density polyethylene vessel and solids allowed to settle overnight. Supernate was then siphoned off and circulated through the shipping container to complete the transfer of the sample. Following thorough mixing of the 3-L sample, a 239 g sub-sample was removed. This sub-sample was then utilized for all subsequent analytical samples. Eight separate aliquots of the slurry were digested, four with HNO{sub 3}/HCl (aqua regia) in sealed Teflon{reg_sign} vessels and four in Na{sub 2}O{sub 2} (alkali or peroxide fusion) using Zr crucibles. Due to the use of Zr crucibles and Na in the peroxide fusions, Na and Zr cannot be determined from this preparation. Additionally, other alkali metals, such as Li and K that may be contaminants in the Na{sub 2}O{sub 2} are not determined from this preparation. Three Analytical Reference Glass-1 (ARG-1) standards were digested along with a blank for each preparation. The ARG-1 glass allows for an assessment of the completeness of each digestion. Each aqua regia digestion and blank was diluted to 1:100 mL with deionized water and submitted to Analytical Development (AD) for inductively coupled plasma--atomic emission spectroscopy (ICPAES) analysis, inductively coupled plasma--mass spectrometry (ICP-MS) analysis of masses 81-209 and 230

  10. MIXTURES OF THYROID DISRUPTING CHEMICALS: TESTING ADDITIVITY OF HEPATIC INDUCERS AND THYROID PEROXIDASE INHIBITORS.

    EPA Science Inventory

    Humans are exposed to chemical mixtures via diet, occupation, and the environment. Previous data demonstrated that low doses of polycyclic halogenated aromatic hydrocarbons (PHAHs) acting through similar mechanisms result in an additive reduction of thyroxine (T4). If xenobioti...

  11. Biological Sampling and Analysis in Sinclair and Dyes Inlets, Washington: Chemical Analyses for 2007 Puget Sound Biota Study

    SciTech Connect

    Brandenberger, Jill M.; Suslick, Carolynn R.; Johnston, Robert K.

    2008-10-09

    Evaluating spatial and temporal trends in contaminant residues in Puget Sound fish and macroinvertebrates are the objectives of the Puget Sound Ambient Monitoring Program (PSAMP). In a cooperative effort between the ENVironmental inVESTment group (ENVVEST) and Washington State Department of Fish and Wildlife, additional biota samples were collected during the 2007 PSAMP biota survey and analyzed for chemical residues and stable isotopes of carbon (δ13C) and nitrogen (δ15N). Approximately three specimens of each species collected from Sinclair Inlet, Georgia Basin, and reference locations in Puget Sound were selected for whole body chemical analysis. The muscle tissue of specimens selected for chemical analyses were also analyzed for δ13C and δ15N to provide information on relative trophic level and food sources. This data report summarizes the chemical residues for the 2007 PSAMP fish and macro-invertebrate samples. In addition, six Spiny Dogfish (Squalus acanthias) samples were necropsied to evaluate chemical residue of various parts of the fish (digestive tract, liver, embryo, muscle tissue), as well as, a weight proportional whole body composite (WBWC). Whole organisms were homogenized and analyzed for silver, arsenic, cadmium, chromium, copper, nickel, lead, zinc, mercury, 19 polychlorinated biphenyl (PCB) congeners, PCB homologues, percent moisture, percent lipids, δ13C, and δ15N.

  12. Metagenomic analyses of the late Pleistocene permafrost - additional tools for reconstruction of environmental conditions

    NASA Astrophysics Data System (ADS)

    Rivkina, Elizaveta; Petrovskaya, Lada; Vishnivetskaya, Tatiana; Krivushin, Kirill; Shmakova, Lyubov; Tutukina, Maria; Meyers, Arthur; Kondrashov, Fyodor

    2016-04-01

    A comparative analysis of the metagenomes from two 30 000-year-old permafrost samples, one of lake-alluvial origin and the other from late Pleistocene Ice Complex sediments, revealed significant differences within microbial communities. The late Pleistocene Ice Complex sediments (which have been characterized by the absence of methane with lower values of redox potential and Fe2+ content) showed a low abundance of methanogenic archaea and enzymes from both the carbon and nitrogen cycles, but a higher abundance of enzymes associated with the sulfur cycle. The metagenomic and geochemical analyses described in the paper provide evidence that the formation of the sampled late Pleistocene Ice Complex sediments likely took place under much more aerobic conditions than lake-alluvial sediments.

  13. Chemical and Solar Electric Propulsion Systems Analyses for Mars Sample Return Missions

    NASA Technical Reports Server (NTRS)

    Donahue, Benjamin B.; Green, Shaun E.; Coverstone, Victoria L.; Woo, Byoungsam

    2004-01-01

    Conceptual in-space transfer stages, including those utilizing solar electric propulsion, chemical propulsion, and chemical propulsion with aerobraking or aerocapture assist at Mars, were evaluated. Roundtrip Mars sample return mission vehicles were analyzed to determine how specific system technology selections influence payload delivery capability. Results show how specific engine, thruster, propellant, capture mode, trip time and launch vehicle technology choices would contribute to increasing payload or decreasing the size of the required launch vehicles. Heliocentric low-thrust trajectory analyses for Solar Electric Transfer were generated with the SEPTOP code.

  14. 76 FR 20992 - Sun Chemical Corp.; Filing of Color Additive Petition

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-14

    ... HUMAN SERVICES Food and Drug Administration Sun Chemical Corp.; Filing of Color Additive Petition AGENCY: Food and Drug Administration, HHS. ACTION: Notice. SUMMARY: The Food and Drug Administration (FDA) is... Director, Office of Food Additive Safety, Center for Food Safety and Applied Nutrition. BILLING CODE...

  15. Factors affecting the microbial and chemical composition of silage. III. Effect of urea additions on maize silage.

    PubMed

    Mahmoud, S A; Abd-el-Hafez, A; Zaki, M M; Saleh, E A

    1978-01-01

    The effect of urea additions on the microbiological and chemical properties of silage, produced from young maize plants (Darawa stage), was studied. Urea treatments, i.e., 0.25%, 0.50%, 0.75%, and 1.00%, stimulated higher densities of the desired microorganisms than the control, while undesired organisms showed lower counts (proteolytic and saccharolytic anaerobes). Addition of 0.25 to 0.50% or urea resulted in the production of high quality silage with pleasant small and high nutritive value, as confirmed by the various microbiological and chemical analyses conducted. Higher levels (0.75 and 1.00%) of urea decreased the quality of the product. PMID:29417

  16. Additional Development and Systems Analyses of Pneumatic Technology for High Speed Civil Transport Aircraft

    NASA Technical Reports Server (NTRS)

    Englar, Robert J.; Willie, F. Scott; Lee, Warren J.

    1999-01-01

    In the Task I portion of this NASA research grant, configuration development and experimental investigations have been conducted on a series of pneumatic high-lift and control surface devices applied to a generic High Speed Civil Transport (HSCT) model configuration to determine their potential for improved aerodynamic performance, plus stability and control of higher performance aircraft. These investigations were intended to optimize pneumatic lift and drag performance; provide adequate control and longitudinal stability; reduce separation flowfields at high angle of attack; increase takeoff/climbout lift-to-drag ratios; and reduce system complexity and weight. Experimental aerodynamic evaluations were performed on a semi-span HSCT generic model with improved fuselage fineness ratio and with interchangeable plain flaps, blown flaps, pneumatic Circulation Control Wing (CCW) high-lift configurations, plain and blown canards, a novel Circulation Control (CC) cylinder blown canard, and a clean cruise wing for reference. Conventional tail power was also investigated for longitudinal trim capability. Also evaluated was unsteady pulsed blowing of the wing high-lift system to determine if reduced pulsed mass flow rates and blowing requirements could be made to yield the same lift as that resulting from steady-state blowing. Depending on the pulsing frequency applied, reduced mass flow rates were indeed found able to provide lift augmentation at lesser blowing values than for the steady conditions. Significant improvements in the aerodynamic characteristics leading to improved performance and stability/control were identified, and the various components were compared to evaluate the pneumatic potential of each. Aerodynamic results were provided to the Georgia Tech Aerospace System Design Lab. to conduct the companion system analyses and feasibility study (Task 2) of theses concepts applied to an operational advanced HSCT aircraft. Results and conclusions from these

  17. Chemical analyses: How to get it done right (customer-analyst interactions)

    SciTech Connect

    Erickson, M.D.

    1995-08-01

    The practical application of chemical analyses begins with a request for the analysis and concludes with provision of the requested analytical data. The key to successful execution of this activity is timely, professional communication between the requester and the analyst. Often chemical analyses are not satisfactorily executed, either because the requester failed to give adequate instructions or because the analyst simply ``did what he or she was told.`` This article addresses the pitfalls of this interaction and provides suggestions for improving the quality of the analytical product through the requester-analyst interface. The request for and conduct of an analysis represents a contract for the procurement of a product (information about the sample); if both parties recognize and abide by this contractual relationship, the process generally proceeds smoothly. Note that the ``customer`` and ``analyst`` may be the same person, especially in a university research environment these same issues hold even in this single-person interaction. This presentation will provide a practical tutorial on how to get chemical analyses done properly and cost-effectively. Suggestions for improving the quality of the analytical product through the requester-analyst interface are provided.

  18. Explanation of non-additive effects in mixtures of similar mode of action chemicals.

    PubMed

    Kamo, Masashi; Yokomizo, Hiroyuki

    2015-09-01

    Many models have been developed to predict the combined effect of drugs and chemicals. Most models are classified into two additive models: independent action (IA) and concentration addition (CA). It is generally considered if the modes of action of chemicals are similar then the combined effect obeys CA; however, many empirical studies report nonlinear effects deviating from the predictions by CA. Such deviations are termed synergism and antagonism. Synergism, which leads to a stronger toxicity, requires more careful management, and hence it is important to understand how and which combinations of chemicals lead to synergism. In this paper, three types of chemical reactions are mathematically modeled and the cause of the nonlinear effects among chemicals with similar modes of action was investigated. Our results show that combined effects obey CA only when the modes of action are exactly the same. Contrary to existing knowledge, combined effects are generally nonlinear even if the modes of action of the chemicals are similar. Our results further show that the nonlinear effects vanish out when the chemical concentrations are low, suggesting that the current management procedure of assuming CA is rarely inappropriate because environmental concentrations of chemicals are generally low.

  19. Chemical Abundance Comparisons Between ASPCAP and Manual Analyses in Open Cluster Red Giants

    NASA Astrophysics Data System (ADS)

    Smith, Verne V.; Cunha, Katia M. L.; Souto, Diogo; Shetrone, Matthew D.; Meszaros, Szabolcs; Allende-Prieto, Carlos; Bizyaev, Dmitry; Carlberg, Joleen K.; García Pérez, Ana; Hasselquist, Sten; Holtzman, Jon A.; Johnson, Jennifer; Majewski, Steven R.; Schiavon, Ricardo P.; Sobeck, Jennifer; Troup, Nicholas William

    2015-01-01

    The APOGEE Stellar Parameter and Chemical Abundance Pipeline (ASPCAP) has now produced individual chemical abundances for 15 different elements: C, N, O, Na, Mg, Al, Si, S, K, Ca, Ti, V, Mn, Fe, and Ni. We will present comparisons of the ASPCAP abundances for stars in clusters with those derived from manual stellar parameter and abundance analyses of the same stars using the APOGEE spectra. These comparisons can be used to assess whether any of the elemental results from the automated pipeline contain larger than expected scatter, systematic offsets, or trends with stellar parameters, such as effective temperature, surface gravity, or metallicity. Using the subset of trustworthy abundances, we present early results of peculiar chemical substructures found in the APOGEE dataset.

  20. Reprocessing the Southern Hemisphere ADditional OZonesondes (SHADOZ) Database for Long-Term Trend Analyses

    NASA Astrophysics Data System (ADS)

    Witte, J. C.; Thompson, A. M.; Coetzee, G.; Fujiwara, M.; Johnson, B. J.; Sterling, C. W.; Cullis, P.; Ashburn, C. E.; Jordan, A. F.

    2015-12-01

    SHADOZ is a large archive of tropical balloon-bone ozonesonde data at NASA/Goddard Space Flight Center with data from 14 tropical and subtropical stations provided by collaborators in Europe, Asia, Latin America and Africa . The SHADOZ time series began in 1998, using electrochemical concentration cell (ECC) ozonesondes. Like many long-term sounding stations, SHADOZ is characterized by variations in operating procedures, launch protocols, and data processing such that biases within a data record and among sites appear. In addition, over time, the radiosonde and ozonesonde instruments and data processing protocols have changed, adding to the measurement uncertainties at individual stations and limiting the reliability of ozone profile trends and continuous satellite validation. Currently, the ozonesonde community is engaged in reprocessing ECC data, with an emphasis on homogenization of the records to compensate for the variations in instrumentation and technique. The goals are to improve the information and integrity of each measurement record and to support calculation of more reliable trends. We illustrate the reprocessing activity of SHADOZ with selected stations. We will (1) show reprocessing steps based on the recent WMO report that provides post-processing guidelines for ozonesondes; (2) characterize uncertainties in various parts of the ECC conditioning process; and (3) compare original and reprocessed data to co-located ground and satellite measurements of column ozone.

  1. Chemical analyses of water samples from the Picher mining area, northeast Oklahoma and southeast Kansas

    USGS Publications Warehouse

    Parkhurst, David L.

    1987-01-01

    Chemical analyses are presented for 169 water samples from Tar Creek drainage and the Picher lead-zinc mining area of northeast Oklahoma and southeast Kansas. Water samples were taken from November 1983 through February 1986 from the abandoned mines, from points of mine-water discharge, and from surface-water locations upstream and downstream from mine discharge area. The pH, temperature, alkalinity, dissolved oxygen, and specific conductance were measured in the field. Laboratory analyses routinely included the major ions plus aluminum, cadmium, copper, iron, lead, manganese, nickel, and zinc. Non-routine analyses of dissolved gases and tritium are presented. Stable carbon-isotope ratios for 11 mine-water samples and three carbonate-rock samples are reported. Miscellaneous stream-discharge measurements made at the time of sampling or taken from gaging-station records are included in the report.

  2. The effect of lactic acid bacterial starter culture and chemical additives on wilted rice straw silage.

    PubMed

    Wang, Yan-Su; Shi, Wei; Huang, Lin-Ting; Ding, Cheng-Long; Dai, Chuan-Chao

    2016-04-01

    Lactic acid bacteria (LAB) are suitable for rice straw silage fermentation, but have been studied rarely, and rice straw as raw material for ensiling is difficult because of its disadvantages, such as low nutrition for microbial activities and low abundances of natural populations of LAB. So we investigated the effect of application of LAB and chemical additives on the fermentation quality and microbial community of wilted rice straw silage. Treatment with chemical additives increased the concentrations of crude protein (CP), water soluble carbohydrate (WSC), acetic acid and lactic acid, reduced the concentrations of acid detergent fiber (ADF) and neutral detergent fiber (NDF), but did not effectively inhibit the growth of spoilage organisms. Inoculation with LABs did not improve the nutritional value of the silage because of poor growth of LABs in wilted rice straw. Inoculation with LAB and addition of chemical materials improved the quality of silage similar to the effects of addition of chemical materials alone. Growth of aerobic and facultatively anaerobic bacteria was inhibited by this mixed treatment and the LAB gradually dominated the microbial community. In summary, the fermentation quality of wilted rice straw silage had improved by addition of LAB and chemical materials. PMID:26429595

  3. The effect of lactic acid bacterial starter culture and chemical additives on wilted rice straw silage.

    PubMed

    Wang, Yan-Su; Shi, Wei; Huang, Lin-Ting; Ding, Cheng-Long; Dai, Chuan-Chao

    2016-04-01

    Lactic acid bacteria (LAB) are suitable for rice straw silage fermentation, but have been studied rarely, and rice straw as raw material for ensiling is difficult because of its disadvantages, such as low nutrition for microbial activities and low abundances of natural populations of LAB. So we investigated the effect of application of LAB and chemical additives on the fermentation quality and microbial community of wilted rice straw silage. Treatment with chemical additives increased the concentrations of crude protein (CP), water soluble carbohydrate (WSC), acetic acid and lactic acid, reduced the concentrations of acid detergent fiber (ADF) and neutral detergent fiber (NDF), but did not effectively inhibit the growth of spoilage organisms. Inoculation with LABs did not improve the nutritional value of the silage because of poor growth of LABs in wilted rice straw. Inoculation with LAB and addition of chemical materials improved the quality of silage similar to the effects of addition of chemical materials alone. Growth of aerobic and facultatively anaerobic bacteria was inhibited by this mixed treatment and the LAB gradually dominated the microbial community. In summary, the fermentation quality of wilted rice straw silage had improved by addition of LAB and chemical materials.

  4. Chemical TOPAZ: Modifications to the heat transfer code TOPAZ: The addition of chemical reaction kinetics and chemical mixtures

    SciTech Connect

    Nichols, A.L. III.

    1990-06-07

    This is a report describing the modifications which have been made to the heat flow code TOPAZ to allow the inclusion of thermally controlled chemical kinetics. This report is broken into parts. The first part is an introduction to the general assumptions and theoretical underpinning that were used to develop the model. The second section describes the changes that have been implemented into the code. The third section is the users manual for the input for the code. The fourth section is a compilation of hints, common errors, and things to be aware of while you are getting started. The fifth section gives a sample problem using the new code. This manual addenda is written with the presumption that most readers are not fluent with chemical concepts. Therefore, we shall in this section endeavor to describe the requirements that must be met before chemistry can occur and how we have modeled the chemistry in the code.

  5. An Excel spreadsheet to classify chemical analyses of amphiboles following the IMA 2012 recommendations

    NASA Astrophysics Data System (ADS)

    Locock, Andrew J.

    2014-01-01

    A Microsoft Excel spreadsheet has been programmed to assist with classification of chemical analyses of orthorhombic and monoclinic amphiboles following the 2012 nomenclature recommended by the International Mineralogical Association. The spreadsheet is intended for use only with compositional data (wt% oxides and halogens, rather than atomic proportions) and provides options for the estimation of Fe3+/ΣFe and Mn3+/ΣMn ratios and OH content. Various cation normalization schemes can be automatically or manually selected. For each analysis, the output includes the group, subgroup (or B-occupancy for the oxo-amphiboles), and species name including any mandatory chemical prefixes, along with a formula based on 24 anions. The formula results can be exported in a form suitable for the AMPH2012 program. Prefixes related to space groups (proto-) and suffixes (-P21/m) are not assigned in the spreadsheet. Large data sets (up to 200 analyses at a time) can be accommodated by the spreadsheet, which is accompanied by results calculated for more than 650 amphibole analyses taken from the literature.

  6. Roseopurpurins: Chemical Diversity Enhanced by Convergent Biosynthesis and Forward and Reverse Michael Additions.

    PubMed

    Shang, Zhuo; Khalil, Zeinab; Li, Li; Salim, Angela A; Quezada, Michelle; Kalansuriya, Pabasara; Capon, Robert J

    2016-09-01

    Cultures of the estuarine fungus Penicillium roseopurpureum (CMB-MF038) yielded a diverse array of polyketides, many of which were related via a highly convergent biosynthetic pathway. In addition to revising and assigning structures, and documenting chemical and biological properties, pro-drug cytotoxic properties were attributed to roseopurpurins H (10) and I (11) on the basis of in situ reverse Michael addition to a cytotoxic Michael acceptor (12). PMID:27537356

  7. Chemical compounds to be used as solid carriers for fuel additives

    SciTech Connect

    Santambrogio, A.; Mattei, L.

    1987-09-08

    This patent describes compositions of dosing additives to fuel for internal combustion engines, comprising (1) solid carrier chemical compounds, which have a melting point between 70/sup 0/C and 130/sup 0/C, are soluble in hydrocarbons and are selected from the group consisting of alkyl-substituted phenols, aromatic carbonates, alkyl-substituted pyrocatechols, and polymers of alkyl-substituted 1,2-dihydroquinoline; and (2) additives for fuel for internal combustion engines which are liquid at room temperature.

  8. 78 FR 68461 - Guidance for Industry: Studies To Evaluate the Utility of Anti-Salmonella Chemical Food Additives...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-14

    ... Anti- Salmonella Chemical Food Additives in Feeds; Request for Comments AGENCY: Food and Drug... Chemical Food Additives in Feeds,'' and is seeking comments on this guidance before revisions are made... Guidance for Industry: Studies to Evaluate the Utility of Anti-Salmonella Chemical Food Additives in...

  9. Chemical Analyses of Ground Water in the Carson Desert near Stillwater, Churchill County, Nevada, 2005

    USGS Publications Warehouse

    Fosbury, DeEtta; Walker, Mark; Stillings, Lisa L.

    2008-01-01

    This report presents the chemical analyses of ground-water samples collected in 2005 from domestic wells located in the Stillwater area of the Carson Desert (fig. 1). These data were evaluated for evidence of mixing with nearby geothermal waters (Fosbury, 2007). That study used several methods to identify mixing zones of ground and geothermal waters using trace elements, chemical equilibria, water temperature, geothermometer estimates, and statistical techniques. In some regions, geothermal sources influence the chemical quality of ground water used for drinking water supplies. Typical geothermal contaminants include arsenic, mercury, antimony, selenium, thallium, boron, lithium, and fluoride (Webster and Nordstrom, 2003). The Environmental Protection Agency has established primary drinking water standards for these, with the exception of boron and lithium. Concentrations of some trace metals in geothermal water may exceed drinking water standards by several orders of magnitude. Geothermal influences on water quality are likely to be localized, depending on directions of ground water flow, the relative volumes of geothermal sources and ground water originating from other sources, and depth below the surface from which water is withdrawn. It is important to understand the areal extent of shallow mixing of geothermal water because it may have adverse chemical and aesthetic effects on domestic drinking water. It would be useful to understand the areal extent of these effects.

  10. Chemical Analyses of Ground and Surface Waters, Ester Dome, Cental Alaska, 2000-2001

    USGS Publications Warehouse

    Verplanck, P.L.; Mueller, S.H.; Youcha, E.K.; Goldfarb, R.J.; Sanzolone, R.F.; McCleskey, R.B.; Briggs, P.H.; Roller, M.; Adams, M.; Nordstrom, D.K.

    2003-01-01

    Water analyses are reported for ground and surface waters collected at 33 sites on and near Ester Dome, Fairbanks area, central Alaska during 2000-2001. This interdisciplinary study focused on documenting the temporal and spatial chemical variations in arsenic concentrations to elucidate the processes that lead to elevated arsenic concentrations in ground water. Field parameters and water analyses are reported for 17 domestic wells, 13 monitoring well sites, and 3 surface water sites. Sampling occurred during November 2000, February 2001, May 2001, July 2001, and September 2001. Waters in the study area are primarily Ca-HCO3 type, with pH values ranging from 5.97 to 7.87. Dissolved arsenic concentrations ranged from less than 3 to 1160 micrograms per liter.

  11. Results of Chemical Analyses for Alcove 8/Niche 3 Tracer Studies

    SciTech Connect

    Daniels, Jeanette

    2006-02-23

    This is the final report detailing the analyses performed under ORD-FY04-011 "Chemical Analyses for Alcove 8/Niche 3 Tracer Studies." The work was performed under the University and Community College System of Nevada (UCCSN) and the Department of Energy (DOE) Cooperative Agreement Number DE-FC28-04RW12232. This task provided method development and analytical support for the Alcove 8/Niche 3 Tracer Studies in the Exploratory Studies Facility (ESF). Concentrations of tracers, as well as major anions and cations, were reported for samples provided by Lawrence Berkeley National Laboratory (LBNL) and the US Geological Survey (USGS). Samples were analyzed using High Performance Liquid Chromatography (HPLC) and Ion Chromatography (IC). Samples were analyzed and controlled according to Implementing Procedures (IP's) written and approved in accordance with the Office of Civilian Radioactive Waste Management (OCRWM) approved Nevada System of Higher Education (NSHE) Quality Assurance Program.

  12. Prediction of metabolisable energy value of broiler diets and water excretion from dietary chemical analyses.

    PubMed

    Carré, B; Lessire, M; Juin, H

    2013-08-01

    Thirty various pelleted diets were given to broilers (8/diet) for in vivo measurements of dietary metabolisable energy (ME) value and digestibilities of proteins, lipids, starch and sugars from day 27 to day 31, with ad libitum feeding and total collection of excreta. Water excretion was also measured. Amino acid formulation of diets was done on the basis of ratios to crude proteins. Mean in vivo apparent ME values corrected to zero nitrogen retention (AMEn) were always lower than the AMEn values calculated for adult cockerels using predicting equations from literature based on the chemical analyses of diets. The difference between mean in vivo AMEn values and these calculated AMEn values increased linearly with increasing amount of wheat in diets (P = 0.0001). Mean digestibilities of proteins, lipids and starch were negatively related to wheat introduction (P = 0.0001). The correlations between mean in vivo AMEn values and diet analytical parameters were the highest with fibre-related parameters, such as water-insoluble cell-walls (WICW) (r = -0.91) or Real Applied Viscosity (RAV) (r = -0.77). Thirteen multiple regression equations relating mean in vivo AMEn values to dietary analytical data were calculated, with R² values ranging from 0.859 to 0.966 (P = 0.0001). The highest R² values were obtained when the RAV parameter was included in independent variables. The direct regression equations obtained with available components (proteins, lipids, starch, sucrose and oligosaccharides) and the indirect regression equations obtained with WICW and ash parameters showed similar R² values. Direct or indirect theoretical equations predicting AMEn values were established using the overall mean in vivo digestibility values. The principle of indirect equations was based on the assumption that WICW and ashes act as diluters. Addition of RAV or wheat content in variables improved the accuracy of theoretical equations. Efficiencies of theoretical equations for predicting AMEn

  13. Organic chemical and biomarker analyses of terrestrial archives - is all what we measure of sedimentary origin?

    NASA Astrophysics Data System (ADS)

    Wiesenberg, G. L.; Gocke, M.

    2012-12-01

    Organic chemical analyses of sedimentary organic matter have been widely used in the past. In terrestrial archives total carbon, organic carbon (Corg) and carbonatic carbon (Ccarb) and their stable isotope composition (δ13C) were established for source assessment of sedimentary matter covering source area (Ccarb) and source vegetation (Corg). Furthermore, radiocarbon dating (Δ14C) was found useful to date sedimentary archives covering the past 50 ka. In addition, the application of biomarkers was tried in sedimentary archives like loess-paleosol sequences to trace source vegetation in more detail. Among others, several alkane molecular proxies have been introduced and adopted in order to assess the contribution of tree and grass vegetation to sedimentary organic matter. Furthermore, other biomarkers like alcohols, fatty acids and others were introduced into the investigation of terrestrial archives. However, studies of the recent 10 years clearly indicate that overprint of sedimentary matter is very likely for terrestrial archives and that caution should be paid, when interpreting chemical results. While secondary carbonate formation is a well known feature covering e.g. loess dolls, pseudomycelia and rhizoliths, commonly these features are not mentioned correctly in a paleoenvironmental context. Nevertheless, they provide unique opportunities for the reassessment of potential contamination of sedimentary organic matter. Especially rhizoliths as calcified root remains can impressively cut vertically through several pairs of sediments and paleosols. While some authors still suggest their formation during sedimentation, we could clearly show different ages of sediments and rhizoliths from the same depth. While some of these root features are easy to see during field campaigns, others are not. This is e.g. observed for biopores in the vicinity of rhizoliths. They can have diameters <0.1 mm and are associated with former fine roots, which must not necessarily be

  14. Spinel dissolution via addition of glass forming chemicals. Results of preliminary experiments

    SciTech Connect

    Fox, K. M.; Johnson, F. C.

    2015-11-01

    Increased loading of high level waste in glass can lead to crystallization within the glass. Some crystalline species, such as spinel, have no practical impact on the chemical durability of the glass, and therefore may be acceptable from both a processing and a product performance standpoint. In order to operate a melter with a controlled amount of crystallization, options must be developed for remediating an unacceptable accumulation of crystals. This report describes preliminary experiments designed to evaluate the ability to dissolve spinel crystals in simulated waste glass melts via the addition of glass forming chemicals (GFCs).

  15. Use of chemical additives with steam injection to increase oil recovery. Final report

    SciTech Connect

    Handy, L.L.

    1984-09-01

    Surfactants and certain inorganic bases have been evaluated as possible chemical additives to improve performance of steamfloods. Special emphasis was given to chemicals which would reduce the residual oil saturation in regions flooded by hot water below the steam zone. Problems considered were the effect of prolonged exposure to steam temperature on the stability of petroleum sulfonates, the effect of temperature on surfactant adsorption and the effect of temperature on interfacial tensions. Methods were developed for measuring quantitatively the thermal stability of the aryl sulfonate class of surfactant. This class includes the petroleum sulfonates. The best of the surfactants evaluated in this study had marginal stability for use with steamfloods. The surfactants in combination with elevated temperatures do reduce residual oil saturations. Data are presented on the temperature effects on interfacial tensions and on adsorption. Certain inorganic chemicals which give high pH are effective and inexpensive but hydroxyl ions react with silica in the reservoir. This reaction is accentuated at higher temperatures. Data show that the pH of the injected hot water with caustic decreases with contact time. The experiments did not permit determining if an equilibrium pH would be obtained which would be high enough to be effective in recovering oil. Core floods showed that pH's in excess of 12 would be required to reduce residual oil saturations if sodium hydroxide was the injected chemical. The addition of surfactants with caustic or the use of sodium carbonate may permit recovery of oil at lower pH's. A reservoir simulator is being developed to predict performance of steamfloods with chemical additives. This has been completed for simple linear floods but is being extended to three dimensions and to more complicated flooding operations. 31 references, 43 figures, 2 tables.

  16. 78 FR 74218 - Imposition of Additional Sanctions on Syria Under the Chemical and Biological Weapons Control and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-10

    ... Imposition of Additional Sanctions on Syria Under the Chemical and Biological Weapons Control and Warfare... chemical weapons in violation of international law or lethal chemical weapons against its own nationals... the Chemical and Biological Weapons Control and Warfare Elimination Act of 1991, 22 U.S.C. 5604(a)...

  17. Effect of Organic Additive on Surface Roughness of Polycrystalline Silicon Film after Chemical Mechanical Polishing

    NASA Astrophysics Data System (ADS)

    Hwang, Hee-Sub; Park, Jin-Hyung; Yi, Sok-Ho; Paik, Ungyu; Park, Jea-Gun

    2010-01-01

    The effect of an organic additive on the surface roughness of a polycrystalline silicon (poly-Si) film was investigated by chemical mechanical polishing (CMP). The surface roughness of the polished poly-Si film was markedly reduced by adding 0.001 wt % hydroxyl ethyl cellulose (HEC) and then decreased slightly with further addition of HEC. We concluded that the reduction of surface roughness was attributed to the formation of a hydroplane layer on the poly-Si surface. Evidence of the hydroplane layer was verified by contact angle and X-ray photoelectron spectroscopy (XPS) measurements.

  18. Metal-contaminated soil remediation by means of paper mill sludges addition: chemical and ecotoxicological evaluation.

    PubMed

    Calace, N; Campisi, T; Iacondini, A; Leoni, M; Petronio, B M; Pietroletti, M

    2005-08-01

    Metal pollution of soils is a great environmental problem. The major risks due to metal pollution of soil consist of leaching to groundwater and potential toxicity to plants and/or animals. The objective of this study is to evaluate by means of chemical and ecotoxicological approach the effects of paper mill sludge addition on the mobile metal fraction of polluted metal soils. The study was carried out on acidic soil derived from mining activities and thus polluted with heavy metals, and on two paper mill sludges having different chemical features. The results obtained by leaching experiments showed that the addition of a paper mill sludge, consisting mainly of carbonates, silicates and organic matter, to a heavy-metal polluted soil produces a decrease of available metal forms. The carbonate content seems to play a key role in the chemical stabilisation of metals and consequently in a decrease of toxicity of soil. The leached solutions have a non-toxic effect. The mild remediation by addition of sludge has moreover a lasting effect.

  19. SELECTED CHEMICAL ANALYSES AND GEOTHERMOMETRY OF HOT SPRING WATERS FROM THE CALABOZOS CALDERA, CENTRAL CHILE.

    USGS Publications Warehouse

    Thompson, J.M.; Grunder, A.L.; Hildreth, Wes

    1983-01-01

    Hot springs discharging from the active hydrothermal system associated with the Calabozos caldera, Chile, have measured orifice temperatures as high as 98. 5 degree C and calculated geothermometer temperatures as high as 250 degree C. Three types of spring waters can be identified from the chemical analyses: a Na-Cl type, a Na-HCO//3 type and a Na-mixed anion type. Chloride-enthalpy relations indicate that the hydrothermal reservoir water may attain temperatures near 342 degree C and that most spring waters are mixed with cold meteoric water. Despite the proximity of Mesozoic marine gypsum deposits, the Cl/Br weight ratio of the Calabozos spring waters does not appear to indicate that these waters have a significant 'marine' signature. Refs.

  20. Is dew water potable? Chemical and biological analyses of dew water in Ajaccio (Corsica Island, France).

    PubMed

    Muselli, Marc; Beysens, Daniel; Soyeux, Emmanuel; Clus, Owen

    2006-01-01

    To determine to what extent dew water is potable without further treatment, a thorough set of chemical and biological analyses were performed on 10 samples of dew water collected on a large scale radiative collector (29.83 m2) in Ajaccio (Corsica Island, France), between 21 May 2002 and 5 Mar. 2003. Samples were collected following four protocols according to the dew volume amount and 48 parameters (ions, minerals, and bacteria) were analyzed and compared to French and European Union legislation and also World Health Organization (WHO) recommendations. Aluminum and Fe were the main pollutants whose concentrations were significantly larger than recommended. Their presence is due to local deposition of aerosols coming from the Sahara (a characteristic of the Mediterranean basin). A large number of biologically cultivable microorganisms were found, together with bacteria typical of fecal contamination. For dew water to be potable with respect to present legislation at the Ajaccio site, it should be disinfected and treated for turbidity.

  1. Effects of temperature and chemical addition on the formation of bromoorganic DBPs during ozonation.

    PubMed

    Zhang, Xiangru; Echigo, Shinya; Lei, Hongxia; Smith, Michael E; Minear, Roger A; Talley, Jeffrey W

    2005-01-01

    The effects of temperature and addition of OH radical scavengers/enhancers or HOBr scavenger on the formation of bromoorganic disinfection byproducts (DBPs) from ozonation of six raw waters were studied in true batch reactors. The formation of bromoorganic DBPs during ozonation generally increased with the increase of temperature, but might also decrease for the waters with somewhat higher values of specific UV absorbance (SUVA). The addition of hydrogen peroxide, ethanol, or ammonium dramatically decreased the formation of bromoorganic DBPs; t-butanol addition significantly increased the formation of bromoorganic DBPs; bicarbonate addition might increase or decrease bromoorganic DBP formation depending on the water source. For all the waters treated with the chemical addition, the level of total organic bromine (TOBr) varied with the same pace as that of ozone exposure (CT), which suggests that TOBr formed during ozonation may be used to estimate the CT, a measure for the achieved degree of disinfection. The results demonstrate that for each water, the correlation between TOBr and CT was less affected by the change of chemical composition of the water than that between BrO(3)(-) and CT; for a given chemical composition and temperature of a water, there generally were well-defined relationships between TOBr and CT, and bromoform and CT just as that between BrO(3)(-) and CT. The possible mechanisms behind the linear functions of TOBr or BrO(3)(-) versus CT were given. Further study is needed to examine whether the trends found in this research can be applicable for the high SUVA waters.

  2. Tying Biological Activity to Changes in Sea Spray Aerosol Chemical Composition via Single Particle Analyses

    NASA Astrophysics Data System (ADS)

    Sultana, C. M.; Lee, C.; Collins, D. B.; Axson, J. L.; Laskina, O.; Grandquist, J. R.; Grassian, V. H.; Prather, K. A.

    2014-12-01

    In remote marine environments, sea spray aerosols (SSA) often represent the greatest aerosol burden, thus having significant impacts on direct radiative interactions and cloud processes. Previous studies have shown that SSA is a complex mixture of inorganic salts and an array of dissolved and particulate organic components. Enrichment of SSA organic content is often correlated to seawater chlorophyll concentrations, a measure of oceanic biological activity. As the physical and chemical properties of aerosols control their radiative effects, recent studies conducted by the Center for Aerosol Impacts on Climate and the Environment have endeavored to further elucidate the ties between marine biological activity and primary SSA chemical composition using highly time resolved single particle analyses. A series of experiments performed in the recently developed Marine Aerosol Reference Tank evaluated the effect of changing marine microbial populations on SSA chemical composition, which was monitored via an aerosol time-of-flight mass spectrometer and a variety of offline spectroscopic and microscopic techniques. Each experiment was initiated using unfiltered and untreated seawater, thus maintaining a high level of biogeochemical complexity. This study is the first of its kind to capture daily changes in the primary SSA mixing state over the growth and death of a natural phytoplankton bloom. Increases in organic aerosol types (0.4-3 μm), internally and externally mixed with sea salt, could not be correlated to chlorophyll concentrations. Maximum production of these populations occurred two to four days after the in vivo chlorophyll fluorescence peaked in intensity. This work is in contrast to the current paradigm of correlating SSA organic content to seawater chlorophyll concentration.

  3. [Effects of nitrogen addition on soil physico-chemical properties and enzyme activities in desertified steppe].

    PubMed

    Su, Jie-Qiong; Li, Xin-Rong; Bao, Jing-Ting

    2014-03-01

    To investigate the impacts of nitrogen (N) enrichment on soil physico-chemical property and soil enzyme activities in desert ecosystems, a field experiment by adding N at 0, 1.75, 3.5, 7, or 14 g N x m(-2) a(-1) was conducted in a temperate desert steppe in the southeastern fringe of the Tengger Desert. The results showed that N addition led to accumulations of total N, NO(3-)-N, NH(4+)-N, and available N in the upper soil (0-10 cm) and subsoil (10-20 cm), however, reductions in soil pH were observed, causing soil acidification to some extent. N addition pronouncedly inhibited soil enzyme activities, which were different among N addition levels, soil depths, and years, respectively. Soil enzyme activities were significantly correlated with the soil N level, soil pH, and soil moisture content, respectively.

  4. Treatment of a dilute waste oil emulsion by chemical addition (CA)-dissolved air flotation (DAF)

    SciTech Connect

    Reed, B.E.; Carriere, P.; Zhu, X.; Lorkowski, T.

    1995-12-31

    Treatment of wastewater from aluminum rolling mill operations is an inherent problem in the aluminum fabrication industry. In this study, wastewater from the manufacturer`s processes was transferred to two holding ponds having a total capacity of about 5 million gallons and a detention time of about 10 days. In the holding ponds, free oil was allowed to rise to the surface where it was periodically removed. Wastewater from the holding ponds was withdrawn from about a depth of 9 ft. and used as influent to a variety of technologies. In this paper, results from the chemical addition (CA)-dissolved air flotation (DAF) portion of the treatability study are presented.

  5. Total reflection X-ray fluorescence analyses of samples from oil refining and chemical industries

    NASA Astrophysics Data System (ADS)

    Vilhunen, J. K.; von Bohlen, A.; Schmeling, M.; Klockenkämper, R.; Klockow, D.

    1997-07-01

    The applicability and performance of the TXRF method for the analysis of sample materials from the oil refining and chemical industries were studied. One objective of the study was to develop rapid analytical procedures for the determination of elements present as traces in size fractionated diesel emission particles, in raw materials of resin production (ureas and phenols) and in trouble-shooting samples. Another goal was to determine the real, rather than the ideal, detection limits for the various applications. Absolute detection limits for most elements found in size fractionated diesel emission particles were below 1 ng. Relative detection limits determined for trace elements in ureas were between 5 and 30 μg kg -1. Only the values for P, S and Ca exceeded this range. Additionally, remarkable differences in trace elements below 1 mg kg -1 could be detected between five commercial ureas.

  6. Nutrients removal and recovery from anaerobically digested swine wastewater by struvite crystallization without chemical additions.

    PubMed

    Song, Yong-Hui; Qiu, Guang-Lei; Yuan, Peng; Cui, Xiao-Yu; Peng, Jian-Feng; Zeng, Ping; Duan, Liang; Xiang, Lian-Cheng; Qian, Feng

    2011-06-15

    Anaerobically digested swine wastewater contains high concentrations of phosphorus (P) and nitrogen (N). A pilot-scale experiment was carried out for nutrients removal and recovery from anaerobically digested swine wastewater by struvite crystallization. In the pilot plant, a sequencing batch reactor (SBR) and a continuous-flow reactor with struvite accumulation devices were designed and employed. The wastewater pH value was increased by CO(2) stripping, and the struvite crystallization process was performed without alkali and Mg(2+) additions. Results of the long-term operation of the system showed that, both reactors provided up to 85% P removal and recovery over wide ranges of aeration times (1.0-4.0 h), hydraulic retention times (HRT) (6.0-15.0 h) and temperatures (0-29.5°C) for an extended period of 247 d, in which approximate 30% of P was recovered by the struvite accumulation devices. However, 40-90% of NH(4)(+)-N removed was through air stripping instead of being immobilized in the recovered solids. The recovered products were detected and analyzed by scanning electron microscope (SEM), X-ray diffraction (XRD) and chemical methods, which were proved to be struvite with purity of more than 90%. This work demonstrated the feasibility and effects of nutrients removal and recovery from anaerobically digested swine wastewater by struvite crystallization without chemical additions.

  7. Evaluation of alternative chemical additives for high-level waste vitrification feed preparation processing

    SciTech Connect

    Seymour, R.G.

    1995-06-07

    During the development of the feed processing flowsheet for the Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS), research had shown that use of formic acid (HCOOH) could accomplish several processing objectives with one chemical addition. These objectives included the decomposition of tetraphenylborate, chemical reduction of mercury, production of acceptable rheological properties in the feed slurry, and controlling the oxidation state of the glass melt pool. However, the DEPF research had not shown that some vitrification slurry feeds had a tendency to evolve hydrogen (H{sub 2}) and ammonia (NH{sub 3}) as the result of catalytic decomposition of CHOOH with noble metals (rhodium, ruthenium, palladium) in the feed. Testing conducted at Pacific Northwest Laboratory and later at the Savannah River Technical Center showed that the H{sub 2} and NH{sub 3} could evolve at appreciable rates and quantities. The explosive nature of H{sub 2} and NH{sub 3} (as ammonium nitrate) warranted significant mitigation control and redesign of both facilities. At the time the explosive gas evolution was discovered, the DWPF was already under construction and an immediate hardware fix in tandem with flowsheet changes was necessary. However, the Hanford Waste Vitrification Plant (HWVP) was in the design phase and could afford to take time to investigate flowsheet manipulations that could solve the problem, rather than a hardware fix. Thus, the HWVP began to investigate alternatives to using HCOOH in the vitrification process. This document describes the selection, evaluation criteria, and strategy used to evaluate the performance of the alternative chemical additives to CHOOH. The status of the evaluation is also discussed.

  8. Characterization of peptides in ensiled alfalfa treated with different chemical additives.

    PubMed

    Ding, Wurong; Guo, Xusheng; Ataku, Kazuo

    2013-12-01

    Effects of different chemical additives on peptide composition in ensiled alfalfa (Medicago sativa L.) were investigated by using gel filtration and determination of N characteristics. The alfalfa silages were prepared untreated (control) or with formic acid, formaldehyde or tannic acid as additives at ensiling. All additives reduced non-protein N (NPN), ammonia nitrogen (NH3 -N) and amino acid N (AA-N) in the ensiled forage, and the most effective reduction of NPN and AA-N was observed in the formaldehyde-treated silages. Peptides in the control silage were mainly dipeptides to peptides with five amino acid residues. Most peptides in the formic acid-treated silage contained 4-12 amino acid residues. Although most peptides in the formaldehyde-treated silages contained 4-6 amino acid residues, there was a considerable proportion of peptides with 7-11 amino acid residues. Tannic acid had little effect on peptide size of ensiled alfalfa extract in which most peptides contained 5-6 amino acid residues. Peptide size in formic acid-treated alfalfa silage was greater than that in the other treatments. Addition of formic acid and formaldehyde not only increased the peptide concentration in alfalfa silage, but enlarged the peptide size.

  9. Assets and pitfalls of chemical and microscopic analyses on gunshot residues in skeletonized bodies: a report of five cases.

    PubMed

    Amadasi, Alberto; Gibelli, Daniele; Mazzarelli, Debora; Porta, Davide; Gaudio, Daniel; Salsarola, Dominic; Brandone, Alberto; Rizzi, Agostino; Cattaneo, Cristina

    2015-07-01

    In case of gunshot wounds, forensic anthropologists and pathologists have many tools at hand, and the assistance that chemical and microscopic investigations can provide in such scenarios is often valuable and crucial. However, the results of such analyses in the search of gunshot residues (GSR) ought not to be acritically considered. We report five cases where chemical (sodium rhodizonate) and microscopic (scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX)) analyses were performed for the search of GSR. Four cases concerned the forensic field and analyses on buried, charred, or submerged remains, whereas one case concerned the historical remains of a soldier of the First World War. In every case, the search for GSR with these techniques showed their persistence even after long periods and preservation in peculiar environments. However, chemical analyses provided their contribution, but in two cases, anthropological analyses provided crucial and solving results. The five cases show the indisputable usefulness of chemical and microscopic analyses in the search of GSR in gunshot wounds and especially how such residues may survive in time and in adverse environmental conditions. However, experts should always be dubious about some pitfalls (such as contamination) one can frequently find in these scenarios. PMID:25394744

  10. Assets and pitfalls of chemical and microscopic analyses on gunshot residues in skeletonized bodies: a report of five cases.

    PubMed

    Amadasi, Alberto; Gibelli, Daniele; Mazzarelli, Debora; Porta, Davide; Gaudio, Daniel; Salsarola, Dominic; Brandone, Alberto; Rizzi, Agostino; Cattaneo, Cristina

    2015-07-01

    In case of gunshot wounds, forensic anthropologists and pathologists have many tools at hand, and the assistance that chemical and microscopic investigations can provide in such scenarios is often valuable and crucial. However, the results of such analyses in the search of gunshot residues (GSR) ought not to be acritically considered. We report five cases where chemical (sodium rhodizonate) and microscopic (scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX)) analyses were performed for the search of GSR. Four cases concerned the forensic field and analyses on buried, charred, or submerged remains, whereas one case concerned the historical remains of a soldier of the First World War. In every case, the search for GSR with these techniques showed their persistence even after long periods and preservation in peculiar environments. However, chemical analyses provided their contribution, but in two cases, anthropological analyses provided crucial and solving results. The five cases show the indisputable usefulness of chemical and microscopic analyses in the search of GSR in gunshot wounds and especially how such residues may survive in time and in adverse environmental conditions. However, experts should always be dubious about some pitfalls (such as contamination) one can frequently find in these scenarios.

  11. Understanding Polycyclic Aromatic Hydrocarbon transfers at the catchment scale combining chemical and fallout radionuclide analyses

    NASA Astrophysics Data System (ADS)

    Gateuille, D.; Evrard, O.; Lefevre, I.; Moreau-Guigon, E.; Alliot, F.; Chevreuil, M.; Mouchel, J.-M.

    2012-04-01

    Reducing environmental contamination constitutes a major challenge for industrialized countries. Furthermore, in the European Union, Water Framework Directive (WFD; Directive 2000/60/EC) requires that the member state water bodies reach good ecological and chemical status by 2015. Polycyclic Aromatic Hydrocarbons (PAHs) are a group of persistent organic pollutants considered as priority pollutants because of their mutagenic and carcinogenic properties. They are mostly emitted by human activities such as household heating or road traffic. Although emissions have decreased during the last decades, a large amount of PAHs have been released into the atmosphere for the last two centuries. In recent years, studies dealing with PAHs have grown in number but most of them were restricted to the measurement of PAHs concentrations in the different compartments of the environment (air, soil, sediment, water, etc.). In this context, there remains a lack of knowledge about the transfers and, consequently, about the persistence of these compounds in the environment. This question is particularly acute in the Seine River basin where very high concentrations in PAHs are reported in sediment, thereby compromising the achievement of the good chemical status required by WFD. Our study aims to quantify PAHs transfers at the catchment scale by combining chemical analysis with gamma spectrometry. Atmospheric fallout, soil, river water and sediment samples were collected in two upstream sub-catchments of the Seine River basin during one year. Chemical analyses, restricted to 15 of the 16 PAHs selected by the US Environmental Protection Agency (USEPA), were carried out to determine PAHs concentrations in all samples. Contamination spectra were used to outline the potential origin of pollution. Measurement of fallout radionuclides (Beryllium-7, Lead-210, Caesium-137) in both rainfall and river sediment provided a way to discriminate between freshly eroded sediment vs. material that

  12. Influence of physico-chemical factors on leaching of chemical additives from aluminium foils used for packaging of food materials.

    PubMed

    Ojha, Priyanka; Ojha, C S; Sharma, V P

    2007-01-01

    In recent years, the use of aluminium foils to wrap foodstuff and commodities has been increased to a great extent. Aluminium was found to leach out from the foil in different simulants particularly in distilled water, acidic and alkaline medium at 60 +/- 2 degrees C for 2 hours and 40 +/- 2 degrees C for 24 hours. The migration was found to be above the permissible limit as laid down by WHO guidelines, that is of 0.2 mg/L of water. The protocol used for this study was based on the recommendation of Bureau of Indian Standard regarding the migration of chemical additives from packaging materials used to pack food items. Migration of the aluminium metal was found significantly higher in acidic and aqueous medium in comparison to alcoholic and saline medium. Higher temperature conditions also enhanced the rate of migration of aluminium in acidic and aqueous medium. Leaching of aluminium metal occurred in double distilled water, acetic acid 3%, normal saline and sodium carbonate, except ethanol 8%, in which aluminium migration was below the detection limit of the instrument where three brands of the aluminium foil samples studied.

  13. Understanding Polycyclic Aromatic Hydrocarbon transfers at the catchment scale combining chemical and fallout radionuclides analyses

    NASA Astrophysics Data System (ADS)

    Gateuille, David; Evrard, Olivier; Lefevre, Irène; Moreau-Guigon, Elodie; Alliot, fabrice; Chevreuil, Marc; Mouchel, Jean-Marie

    2013-04-01

    Contamination of river water and sediment constitutes a major environmental issue for industrialized countries. Polycyclic Aromatic Hydrocarbons (PAHs) are a group of persistent organic pollutants characterized by two or more fused rings. In recent years, studies dealing with PAHs have grown in number. Some PAHs present indeed a high risk for environment and human health because of their carcinogenic and mutagenic properties. However, most of these studies focused on measuring PAH concentration in the different compartments of the environment (air, soil, sediment, water, etc.) In this context, there remains a lack of understanding regarding the various processes responsible for PAH transfers from one environmental compartment to another. Our study aims to quantify PAHs transfers at the catchment scale by combining chemical analysis with gamma spectrometry. Air, soil, river water and sediment samples (n=820) were collected in two upstream sub-catchments of the Seine River basin (France) during one year. Chemical analyses were carried out to determine PAHs concentrations in all samples. Furthermore, measurement of fallout radionuclides (Beryllium-7, Lead-210, Caesium-137) in both rainfall and river sediment provided a way to discriminate between freshly eroded sediment vs. resuspension of older material that previously deposited on the riverbed. This information is crucial to estimate PAH residence time and transfer velocities in the Seine River basin. The results show that the PAH behaviour varies from one subcatchment to the next. PAH transfers depend indeed on both the characteristics of the catchment (e.g. topography, presence of drained cropland in catchments) and the local anthropogenic pressures. A significant increase in atmospheric deposition of PAHs is observed during winter due to a larger number of sources (household heating). The 14-month study has also highlighted the seasonal variations of PAH fluxes, which are mainly related to the hydrological

  14. Effect of additives on the properties of polyaniline nanofibers prepared by high gravity chemical oxidative polymerization.

    PubMed

    Zhao, Yibo; Arowo, Moses; Wu, Wei; Chen, Jianfeng

    2015-05-12

    Polyaniline (PANI) nanofibers with improved properties were prepared by high gravity chemical oxidative polymerization in a rotating packed bed with the assistance of p-aminodiphenylamine (AD) and p-phenylenediamine (AP). The effects of reactor type, additive dosage, reaction temperature, and high-gravity level on the properties of products were investigated in detail. Three conclusions were made: (1) a small amount of additive can significantly improve some properties of the nanofibers such as uniformity, specific surface area, and specific capacitance; (2) in order to obtain high-quality nanofibers, the high-gravity level should coordinate with the reaction rate; (3) the molecular weight and conductivity of PANI decrease with the increase of additive dosage. The products have larger specific surface areas of up to 73.9 and 68.4 m(2)/g and consequently improved specific capacitance of up to 527.5 and 552 F/g for the PANI nanofibers prepared with AD and AP, respectively. However, the specific surface area and specific capacitance of pure PANI are only 49.1 m(2)/g and 333.3 F/g, respectively. This research provides a simple, reliable, and scalable method to produce PANI nanofibers of high performances.

  15. Burst and Principal Components Analyses of MEA Data Separates Chemicals by Class

    EPA Science Inventory

    Microelectrode arrays (MEAs) detect drug and chemical induced changes in action potential "spikes" in neuronal networks and can be used to screen chemicals for neurotoxicity. Analytical "fingerprinting," using Principal Components Analysis (PCA) on spike trains recorded from prim...

  16. Method development for simultaneous analyses of multiple legacy and emerging organic chemicals in sediments.

    PubMed

    Guo, Jiehong; Li, Zhuona; Sandy, Andy L; Li, An

    2014-11-28

    The objective of this work was to investigate the feasibility of using a single pretreatment procedure for the analyses of multiple groups of organics, which have a wide range of chemical structures and physicochemical properties, in sediment samples. Nine groups of 162 individual compounds (including 11 surrogates) were investigated, including polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), polychlorinated diphenyl ethers (PCDEs), polychlorinated naphthalenes (PCNs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), novel halogenated flame retardants (nXFRs), musk fragrances (MFs) and organophosphate flame retardants (OPFRs). The individual and grouped recoveries of spiked analytes from adsorption chromatographic columns using either only fully activated, neutral silica gel (SG) or the combinations of silica gel and alumina (Si/Al) sorbents were compared. The results showed a generally stronger adsorption and more effective fractionation on the Si/Al column than on the SG column. The dependence of fractionation on halogen substitution, molecular planarity, and polar functional groups was discussed. The effects of adding sulfuric acid with two different methods were investigated, and the recoveries of a number of MFs, OCPs, nXFRs and OPFRs were recovered less than 60%. Sodium hydroxide treatment of silica gel had minor effects on some OPFRs. Copper used to remove elemental sulfur did not affect the recoveries of all target analytes except chloroneb. The finalized method was validated by spiking the target analysts into the sediment samples and comparing the analytical results of this work on two standard reference materials for sediment (SRMs 1941b and 1944) with the certified or reference values. PMID:25454124

  17. Method development for simultaneous analyses of multiple legacy and emerging organic chemicals in sediments.

    PubMed

    Guo, Jiehong; Li, Zhuona; Sandy, Andy L; Li, An

    2014-11-28

    The objective of this work was to investigate the feasibility of using a single pretreatment procedure for the analyses of multiple groups of organics, which have a wide range of chemical structures and physicochemical properties, in sediment samples. Nine groups of 162 individual compounds (including 11 surrogates) were investigated, including polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), polychlorinated diphenyl ethers (PCDEs), polychlorinated naphthalenes (PCNs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), novel halogenated flame retardants (nXFRs), musk fragrances (MFs) and organophosphate flame retardants (OPFRs). The individual and grouped recoveries of spiked analytes from adsorption chromatographic columns using either only fully activated, neutral silica gel (SG) or the combinations of silica gel and alumina (Si/Al) sorbents were compared. The results showed a generally stronger adsorption and more effective fractionation on the Si/Al column than on the SG column. The dependence of fractionation on halogen substitution, molecular planarity, and polar functional groups was discussed. The effects of adding sulfuric acid with two different methods were investigated, and the recoveries of a number of MFs, OCPs, nXFRs and OPFRs were recovered less than 60%. Sodium hydroxide treatment of silica gel had minor effects on some OPFRs. Copper used to remove elemental sulfur did not affect the recoveries of all target analytes except chloroneb. The finalized method was validated by spiking the target analysts into the sediment samples and comparing the analytical results of this work on two standard reference materials for sediment (SRMs 1941b and 1944) with the certified or reference values.

  18. Effect of chemical additives on Bacillus thuringiensis (Bacillales: Bacillaceae) against Plutella xylostella (Lepidoptera: Pyralidae).

    PubMed

    Zhang, L; Qiu, S; Huang, T; Huang, Z; Xu, L; Wu, C; Gelbic, I; Guan, X

    2013-06-01

    To examine the effect of chemical additives on Bacillus thuringiensis (Berliner) against Plutella xylostella (L.), inorganic salts, nitrogenous compounds, protein solubilizing agents, and organic acids were selected and tested. The chosen materials are low in cost and environmentally safe. Results show that many inorganic salts can increase the activity of B. thuringiensis in a range of 1.31- to 3.08-fold. These include calcium acetate, calcium chloride, calcium hydroxide, calcium sulfate, calcium carbonate, sodium carbonate, sodium acetate, potassium hydroxide, potassium carbonate, potassium acetate, magnesium chloride, magnesium sulfate, and zinc sulfate. Nitrogenous compounds, including peptone, sodium nitrate, and ammonium nitrate, can enhance the activity of B. thuringiensis 1.62-, 1.32-, and 1.37-fold, respectively. Among the protein solubilizing agents, EDTA, urea, mercaptoethanol and dipotassium hydrogen phosphate increased the activity of B. thuringiensis 1.62- to 2.34-fold. Among the organic acids, maleic and citric acids boosted the activity 1.45- and 1.55-fold, respectively. Meanwhile, sodium benzoate and resorcinol led to 1.74- and 1.44-fold activity gains, respectively. Use of appropriate additives could provide great benefit not only in reducing the costs for field applications of biological insecticides but also by boosting the efficacy of B. thuringiensis. PMID:23865169

  19. Toxicogenomics concepts and applications to study hepatic effects of food additives and chemicals

    SciTech Connect

    Stierum, Rob . E-mail: stierum@voeding.tno.nl; Heijne, Wilbert; Kienhuis, Anne; Ommen, Ben van; Groten, John

    2005-09-01

    Transcriptomics, proteomics and metabolomics are genomics technologies with great potential in toxicological sciences. Toxicogenomics involves the integration of conventional toxicological examinations with gene, protein or metabolite expression profiles. An overview together with selected examples of the possibilities of genomics in toxicology is given. The expectations raised by toxicogenomics are earlier and more sensitive detection of toxicity. Furthermore, toxicogenomics will provide a better understanding of the mechanism of toxicity and may facilitate the prediction of toxicity of unknown compounds. Mechanism-based markers of toxicity can be discovered and improved interspecies and in vitro-in vivo extrapolations will drive model developments in toxicology. Toxicological assessment of chemical mixtures will benefit from the new molecular biological tools. In our laboratory, toxicogenomics is predominantly applied for elucidation of mechanisms of action and discovery of novel pathway-supported mechanism-based markers of liver toxicity. In addition, we aim to integrate transcriptome, proteome and metabolome data, supported by bioinformatics to develop a systems biology approach for toxicology. Transcriptomics and proteomics studies on bromobenzene-mediated hepatotoxicity in the rat are discussed. Finally, an example is shown in which gene expression profiling together with conventional biochemistry led to the discovery of novel markers for the hepatic effects of the food additives butylated hydroxytoluene, curcumin, propyl gallate and thiabendazole.

  20. Late Chondritic Additions and Planet and Planetesimal Growth: Evaluation of Physical and Chemical Mechanisms

    NASA Technical Reports Server (NTRS)

    Righter, Kevin

    2013-01-01

    Studies of terrestrial peridotite and martian and achondritic meteorites have led to the conclusion that addition of chondritic material to growing planets or planetesimals, after core formation, occurred on Earth, Mars, asteroid 4 Vesta, and the parent body of the angritic meteorites [1-4]. One study even proposed that this was a common process in the final stages of growth [5]. These conclusions are based almost entirely on the highly siderophile elements (HSE; Re, Au, Pt, Pd, Rh, Ru, Ir, Os). The HSE are a group of eight elements that have been used to argue for late accretion of chondritic material to the Earth after core formation was complete (e.g., [6]). This idea was originally proposed because the D(metal/silicate) values for the HSE are so high, yet their concentration in the mantle is too high to be consistent with such high Ds. The HSE also are present in chondritic relative abundances and hence require similar Ds if this is the result of core-mantle equilibration. Since the work of [6] there has been a realization that core formation at high PT conditions can explain the abundances of many siderophile elements in the mantle (e.g., [7]), but such detailed high PT partitioning data are lacking for many of the HSE to evaluate whether such ideas are viable for all four bodies. Consideration of other chemical parameters reveals larger problems that are difficult to overcome, but must be addressed in any scenario which calls on the addition of chondritic material to a reduced mantle. Yet these problems are rarely discussed or emphasized, making the late chondritic (or late veneer) addition hypothesis suspect.

  1. Chemical analyses and K-Ar ages of samples from 13 drill holes, Medicine Lake volcano, California

    USGS Publications Warehouse

    Donnelly-Nolan, Julie M.

    2006-01-01

    Chemical analyses and K-Ar ages are presented for rocks sampled from drill holes at Medicine Lake volcano, northern California. A location map and a cross-section are included, as are separate tables for drill hole information, major and trace element data, and for K-Ar dates.

  2. Chemical analyses of igneous rocks published from 1884 to 1900, with a critical discussion of the character and use of analyses

    USGS Publications Warehouse

    Washington, H.S.

    1903-01-01

    In the first two or three decades of the last century, when the study of rocks as such was being differentiated from that of minerals and of rock terranes that is, when the science of petrogaphy was in its infancy little attention was paid to their chemical features. It is true that a number had been analyzed, but these were for the most part rocks that were of such a character as to lead the investigator of those early days to consider them as minerals, as was the case with the first described Ihcrzolite and wehrlite. In contradistinction to the individually well-defined minerals, rocks were regarded as merely aggregates of minerals, in presumably fortuitous combinations, and lacking that definiteness or constancy of composition in one mass or in different masses which would justify their chemical study as a whole. As, however, they became more and more the subjects of special research, beginning with the earliest investigations of Cordiera, a knowledge of their chemical composition assumed gradually increasing interest. The great importance of this side of the study of rocks was first clearly recognized by Abich, who pointed out, as early as 1841, the, necessity of a knowledge of their chemical composition for the solution of such problems as their origin, mode of formation, and connection with the interior of the earth, as well as the value of a comparison of their analyses as a proper basis for their classification and nomenclature. To him, therefore, is due the credit, of introducing the chemical composition of rocks as a basis for their classification; though the good influence of this suggestion for their right understanding was largely nullified by the coincident use of the feldspars alone as one of the main factors of classification, an idea which has had a deplorably retarding influence on the development of systematic petrography for many years, and which, even at the present day, holds many systematists firmly in its grasp.

  3. LIFE Chamber Chemical Equilibrium Simulations with Additive Hydrogen, Oxygen, and Nitrogen

    SciTech Connect

    DeMuth, J A; Simon, A J

    2009-09-03

    In order to enable continuous operation of a Laser Inertial confinement Fusion Energy (LIFE) engine, the material (fill-gas and debris) in the fusion chamber must be carefully managed. The chamber chemical equilibrium compositions for post-shot mixtures are evaluated to determine what compounds will be formed at temperatures 300-5000K. It is desired to know if carbon and or lead will deposit on the walls of the chamber, and if so: at what temperature, and what elements can be added to prevent this from happening. The simulation was conducted using the chemical equilibrium solver Cantera with a Matlab front-end. Solutions were obtained by running equilibrations at constant temperature and constant specific volume over the specified range of temperatures. It was found that if nothing is done, carbon will deposit on the walls once it cools to below 2138K, and lead below 838K. Three solutions to capture the carbon were found: adding pure oxygen, hydrogen/nitrogen combo, and adding pure nitrogen. The best of these was the addition of oxygen which would readily form CO at around 4000K. To determine the temperature at which carbon would deposit on the walls, temperature solutions to evaporation rate equations needed to be found. To determine how much carbon or any species was in the chamber at a given time, chamber flushing equations needed to be developed. Major concerns are deposition of carbon and/or oxygen on the tungsten walls forming tungsten oxides or tungsten carbide which could cause embrittlement and cause failure of the first wall. Further research is needed.

  4. Spectroscopic analyses of chemical adaptation processes within microalgal biomass in response to changing environments.

    PubMed

    Vogt, Frank; White, Lauren

    2015-03-31

    Via photosynthesis, marine phytoplankton transforms large quantities of inorganic compounds into biomass. This has considerable environmental impacts as microalgae contribute for instance to counter-balancing anthropogenic releases of the greenhouse gas CO2. On the other hand, high concentrations of nitrogen compounds in an ecosystem can lead to harmful algae blooms. In previous investigations it was found that the chemical composition of microalgal biomass is strongly dependent on the nutrient availability. Therefore, it is expected that algae's sequestration capabilities and productivity are also determined by the cells' chemical environments. For investigating this hypothesis, novel analytical methodologies are required which are capable of monitoring live cells exposed to chemically shifting environments followed by chemometric modeling of their chemical adaptation dynamics. FTIR-ATR experiments have been developed for acquiring spectroscopic time series of live Dunaliella parva cultures adapting to different nutrient situations. Comparing experimental data from acclimated cultures to those exposed to a chemically shifted nutrient situation reveals insights in which analyte groups participate in modifications of microalgal biomass and on what time scales. For a chemometric description of these processes, a data model has been deduced which explains the chemical adaptation dynamics explicitly rather than empirically. First results show that this approach is feasible and derives information about the chemical biomass adaptations. Future investigations will utilize these instrumental and chemometric methodologies for quantitative investigations of the relation between chemical environments and microalgal sequestration capabilities. PMID:25813024

  5. Spectroscopic analyses of chemical adaptation processes within microalgal biomass in response to changing environments.

    PubMed

    Vogt, Frank; White, Lauren

    2015-03-31

    Via photosynthesis, marine phytoplankton transforms large quantities of inorganic compounds into biomass. This has considerable environmental impacts as microalgae contribute for instance to counter-balancing anthropogenic releases of the greenhouse gas CO2. On the other hand, high concentrations of nitrogen compounds in an ecosystem can lead to harmful algae blooms. In previous investigations it was found that the chemical composition of microalgal biomass is strongly dependent on the nutrient availability. Therefore, it is expected that algae's sequestration capabilities and productivity are also determined by the cells' chemical environments. For investigating this hypothesis, novel analytical methodologies are required which are capable of monitoring live cells exposed to chemically shifting environments followed by chemometric modeling of their chemical adaptation dynamics. FTIR-ATR experiments have been developed for acquiring spectroscopic time series of live Dunaliella parva cultures adapting to different nutrient situations. Comparing experimental data from acclimated cultures to those exposed to a chemically shifted nutrient situation reveals insights in which analyte groups participate in modifications of microalgal biomass and on what time scales. For a chemometric description of these processes, a data model has been deduced which explains the chemical adaptation dynamics explicitly rather than empirically. First results show that this approach is feasible and derives information about the chemical biomass adaptations. Future investigations will utilize these instrumental and chemometric methodologies for quantitative investigations of the relation between chemical environments and microalgal sequestration capabilities.

  6. Testing for Additivity in Chemical Mixtures Using a Fixed-Ratio Ray Design and Statistical Equivalence Testing Methods

    EPA Science Inventory

    Fixed-ratio ray designs have been used for detecting and characterizing interactions of large numbers of chemicals in combination. Single chemical dose-response data are used to predict an “additivity curve” along an environmentally relevant ray. A “mixture curve” is estimated fr...

  7. Review and evaluation of literature on testing of chemical additives for scale control in geothermal fluids. Final report

    SciTech Connect

    Crane, C.H.; Kenkeremath, D.C.

    1981-01-01

    A selected group of reported tests of chemical additives in actual geothermal fluids are reviewed and evaluated to summarize the status of chemical scale-control testing and identify information and testing needs. The task distinguishes between scale control in the cooling system of a flash plant and elsewhere in the utilization system due to the essentially different operating environments involved. Additives for non-cooling geothermal fluids are discussed by scale type: silica, carbonate, and sulfide.

  8. Chemical and Sensory Quality Preservation in Coated Almonds with the Addition of Antioxidants.

    PubMed

    Larrauri, Mariana; Demaría, María Gimena; Ryan, Liliana C; Asensio, Claudia M; Grosso, Nelson R; Nepote, Valeria

    2016-01-01

    Almonds provide many benefits such as preventing heart disease due to their high content of oleic fatty acid-rich oil and other important nutrients. However, they are susceptible to oxidation reactions causing rancidity during storage. The objective of this work was to evaluate the chemical and sensory quality preservation of almonds coated with carboxymethyl cellulose and with the addition of natural and synthetic antioxidants during storage. Four samples were prepared: almonds without coating (C), almonds coated with carboxymethyl cellulose (CMC), almonds coated with CMC supplemented with peanut skins extract (E), and almonds coated with CMC and supplemented with butylhydroxytoluene (BHT). Proximate composition and fatty acid profile were determined on raw almonds. Almond samples (C, CMC, E and BHT) were stored at 40 °C for 126 d. Lipid oxidation indicators: peroxide value (PV), conjugated dienes (CD), volatile compounds (hexanal and nonanal), and sensory attributes were determined for the stored samples. Samples showed small but significant increases in PV, CD, hexanal and nonanal contents, and intensity ratings of negative sensory attributes (oxidized and cardboard). C had the highest tendency to deterioration during storage. At the end of storage (126 d), C had the highest PV (3.90 meqO2 /kg), and BHT had the lowest PV (2.00 meqO2 /kg). CMC and E samples had similar intermediate PV values (2.69 and 2.57 meqO2 /kg, respectively). CMC coating and the addition of natural (peanut skin extract) and synthetic (BHT) antioxidants provide protection to the roasted almond product.

  9. Chemical and Sensory Quality Preservation in Coated Almonds with the Addition of Antioxidants.

    PubMed

    Larrauri, Mariana; Demaría, María Gimena; Ryan, Liliana C; Asensio, Claudia M; Grosso, Nelson R; Nepote, Valeria

    2016-01-01

    Almonds provide many benefits such as preventing heart disease due to their high content of oleic fatty acid-rich oil and other important nutrients. However, they are susceptible to oxidation reactions causing rancidity during storage. The objective of this work was to evaluate the chemical and sensory quality preservation of almonds coated with carboxymethyl cellulose and with the addition of natural and synthetic antioxidants during storage. Four samples were prepared: almonds without coating (C), almonds coated with carboxymethyl cellulose (CMC), almonds coated with CMC supplemented with peanut skins extract (E), and almonds coated with CMC and supplemented with butylhydroxytoluene (BHT). Proximate composition and fatty acid profile were determined on raw almonds. Almond samples (C, CMC, E and BHT) were stored at 40 °C for 126 d. Lipid oxidation indicators: peroxide value (PV), conjugated dienes (CD), volatile compounds (hexanal and nonanal), and sensory attributes were determined for the stored samples. Samples showed small but significant increases in PV, CD, hexanal and nonanal contents, and intensity ratings of negative sensory attributes (oxidized and cardboard). C had the highest tendency to deterioration during storage. At the end of storage (126 d), C had the highest PV (3.90 meqO2 /kg), and BHT had the lowest PV (2.00 meqO2 /kg). CMC and E samples had similar intermediate PV values (2.69 and 2.57 meqO2 /kg, respectively). CMC coating and the addition of natural (peanut skin extract) and synthetic (BHT) antioxidants provide protection to the roasted almond product. PMID:26595771

  10. Multi-Platform Metabolomic Analyses of Rat Urine Following Exposure to Perfluorinated Chemicals (PFCs)

    EPA Science Inventory

    Perfluorinated chemicals (PFCs), namely perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), represent an emerging class of persistent and bioaccumulative compounds. Global occurrence of these fluorochemicals, coupled with probable human exposure, has prompted inv...

  11. Guidelines for the identification of unknown samples for laboratories performing forensic analyses for chemical terrorism.

    PubMed

    Magnuson, Matthew L; Satzger, R Duane; Alcaraz, Armando; Brewer, Jason; Fetterolf, Dean; Harper, Martin; Hrynchuk, Ronald; McNally, Mary F; Montgomery, Madeline; Nottingham, Eric; Peterson, James; Rickenbach, Michael; Seidel, Jimmy L; Wolnik, Karen

    2012-05-01

    Since the early 1990s, the FBI Laboratory has sponsored Scientific Working Groups to improve discipline practices and build consensus among the forensic community. The Scientific Working Group on the Forensic Analysis of Chemical, Biological, Radiological and Nuclear Terrorism developed guidance, contained in this document, on issues forensic laboratories encounter when accepting and analyzing unknown samples associated with chemical terrorism, including laboratory capabilities and analytical testing plans. In the context of forensic analysis of chemical terrorism, this guidance defines an unknown sample and addresses what constitutes definitive and tentative identification. Laboratory safety, reporting issues, and postreporting considerations are also discussed. Utilization of these guidelines, as part of planning for forensic analysis related to a chemical terrorism incident, may help avoid unfortunate consequences not only to the public but also to the laboratory personnel.

  12. Analyses of microbial community within a composter operated using household garbage with special reference to the addition of soybean oil.

    PubMed

    Aoshima, M; Pedro, M S; Haruta, S; Ding, L; Fukada, T; Kigawa, A; Kodama, T; Ishii, M; Igarashi, Y

    2001-01-01

    A commercially available composter was operated using fixed composition of garbage with or without the addition of soybean oil. The composter was operated without adding seed microorganisms or bulking materials. Microflora within the composter were analyzed by denaturing gradient gel electrophoresis (DGGE) in the case of oil addition, or by 16/18 S rRNA gene sequencing of the isolated microorganisms in the case of no oil addition. The results showed that, irrespective of the addition of oil, the bacteria identified were all gram positive, and that lactobacilli seemed to be the key microorganisms. Based on the results, suitable microflora for use in a household composter are discussed.

  13. A Four-Step and Four-Criteria Approach for Evaluating Evidence of Dose Addition in Chemical Mixture Toxicity

    EPA Science Inventory

    Dose addition is the most frequently-used component-based approach for predicting dose response for a mixture of toxicologically-similar chemicals and for statistical evaluation of whether the mixture response is consistent with dose additivity and therefore predictable from the ...

  14. Chemical and Physical Reactions of Wellbore Cement under CO2 Storage Conditions: Effects of Cement Additives

    NASA Astrophysics Data System (ADS)

    Kutchko, B. G.; Strazisar, B. R.; Huerta, N.; Lowry, G. V.; Dzombak, D. A.; Thaulow, N.

    2008-12-01

    Sequestration of CO2 into geologic formations requires long-term storage and low leakage rates to be effective. Active and abandoned wells in candidate storage formations must be evaluated as potential leakage points. Wellbore integrity is an important part of an overall integrated assessment program being developed at NETL to assess potential risks at CO2 storage sites. Such a program is needed for ongoing policy and regulatory decisions for geologic carbon sequestration. The permeability and integrity of the cement in the well is a primary factor affecting its ability to prevent leakage. Cement must be able to maintain low permeability over lengthy exposure to reservoir conditions in a CO2 injection and storage scenario. Although it is known that cement may be altered by exposure to CO2, the results of ongoing research indicate that cement curing conditions, fluid properties, and cement additives play a significant role in the rate of alteration and reaction. The objective of this study is to improve understanding of the factors affecting wellbore cement integrity for large-scale geologic carbon sequestration projects. Due to the high frequency use of additives (pozzolan) in wellbore cement, it is also essential to understand the reaction of these cement-pozzolan systems upon exposure to CO2 under sequestration conditions (15.5 MPa and 50°C). Laboratory experiments were performed to determine the physical and chemical changes, as well as the rate of alteration of commonly used pozzolan-cement systems under simulated sequestration reservoir conditions, including both supercritical CO2 and CO2-saturated brine. The rate of alteration of the cement-pozzolan systems is considerably faster than with neat cement. However, the alteration of physical properties is much less significant with the pozzolanic blends. Permeability of a carbonated pozzolanic cement paste remains sufficiently small to block significant vertical migration of CO2 in a wellbore. All of the

  15. Meta-code for systematic analysis of chemical addition (SACHA): application to fluorination of C70 and carbon nanostructure growth.

    PubMed

    Ewels, Christopher P; Lier, Gregory Van; Geerlings, Paul; Charlier, Jean-Christophe

    2007-01-01

    We present a new computer program able to systematically study chemical addition to and growth or evolution of carbon nanostructures. SACHA is a meta-code able to exploit a wide variety of pre-existing molecular structure codes, automating the otherwise onerous task of constructing, running, and analyzing the large number of input files that are required when exploring structural isomers and addition paths. By way of examples we consider fluorination of the fullerene cage C70 and carbon nanostructure growth through C2 addition. We discuss the possibilities for extension of this technique to rapidly and efficiently explore structural energy landscapes and application to other areas of chemical and materials research.

  16. Students' Predictions about the Sensory Properties of Chemical Compounds: Additive versus Emergent Frameworks

    ERIC Educational Resources Information Center

    Talanquer, Vicente

    2008-01-01

    We investigated general chemistry students' intuitive ideas about the expected properties of the products of a chemical reaction. In particular, we analyzed college chemistry students' predictions about the color, smell, and taste of the products of chemical reactions represented at the molecular level. The study was designed to explore the extent…

  17. 75 FR 17333 - Addition of National Toxicology Program Carcinogens; Community Right-to-Know Toxic Chemical...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-06

    ... affected by this action if you manufacture, process, or otherwise use any of the chemicals ] included in... 372 subpart B of Title 40 of the Code of Federal Regulations. If you have questions regarding the.... EPCRA section 313(d)(2) states that EPA may add a chemical to the list if any of the listing......

  18. Teachers' Misconceptions about the Effects of Addition of More Reactants or Products on Chemical Equilibrium

    ERIC Educational Resources Information Center

    Cheung, Derek; Ma, Hong-jia; Yang, Jie

    2009-01-01

    The importance of research on misconceptions about chemical equilibrium is well recognized by educators, but in the past, researchers' interest has centered on student misconceptions and has neglected teacher misconceptions. Focusing on the effects of adding more reactants or products on chemical equilibrium, this article discusses the various…

  19. Physical/chemical and microbiological analyses of dusts at a resource recover plant.

    PubMed

    Duckett, E J; Wagner, J; Welker, R; Rogers, B; Usdin, V

    1980-12-01

    Airborne dusts at a resource recovery pilot plant were sampled and analyzed to determine physical, chemical and microbiological characteristics. The sampling device was a multi-stage impactor equipped with a pre-collector. Dusts are primarily fibrous organic materials, predominantly of nonrespirable size. Microbiological aerosol concentrations are reported and discussed.

  20. Colophony in mascara as a cause of eyelid dermatitis. Chemical analyses and patch testing.

    PubMed

    Karlberg, A T; Lidén, C; Ehrin, E

    1991-01-01

    Contact allergy to various components in cosmetics may cause eyelid dermatitis. Of 8 mascaras analysed with High Performance Liquid Chromatography (HPLC), 3 contained colophony. Patients with contact allergy to colophony showed positive patch test reactions when tested with the two mascaras with the highest content of colophony. One mascara without colophony but containing nickel, gave positive reactions in persons with contact allergy to nickel.

  1. Statistical Data Analyses of Trace Chemical, Biochemical, and Physical Analytical Signatures

    SciTech Connect

    Udey, Ruth Norma

    2013-01-01

    Analytical and bioanalytical chemistry measurement results are most meaningful when interpreted using rigorous statistical treatments of the data. The same data set may provide many dimensions of information depending on the questions asked through the applied statistical methods. Three principal projects illustrated the wealth of information gained through the application of statistical data analyses to diverse problems.

  2. Medicinal Plants Recommended by the World Health Organization: DNA Barcode Identification Associated with Chemical Analyses Guarantees Their Quality

    PubMed Central

    Palhares, Rafael Melo; Gonçalves Drummond, Marcela; dos Santos Alves Figueiredo Brasil, Bruno; Pereira Cosenza, Gustavo; das Graças Lins Brandão, Maria; Oliveira, Guilherme

    2015-01-01

    Medicinal plants are used throughout the world, and the regulations defining their proper use, such as identification of the correct species and verification of the presence, purity and concentration of the required chemical compounds, are widely recognized. Herbal medicines are made from vegetal drugs, the processed products of medicinal species. These processed materials present a number of challenges in terms of botanical identification, and according to the World Health Organization (WHO), the use of incorrect species is a threat to consumer safety. The samples used in this study consisted of the dried leaves, flowers and roots of 257 samples from 8 distinct species approved by the WHO for the production of medicinal herbs and sold in Brazilian markets. Identification of the samples in this study using DNA barcoding (matK, rbcL and ITS2 regions) revealed that the level of substitutions may be as high as 71%. Using qualitative and quantitative chemical analyses, this study identified situations in which the correct species was being sold, but the chemical compounds were not present. Even more troubling, some samples identified as substitutions using DNA barcoding contained the chemical compounds from the correct species at the minimum required concentration. This last situation may lead to the use of unknown species or species whose safety for human consumption remains unknown. This study concludes that DNA barcoding should be used in a complementary manner for species identification with chemical analyses to detect and quantify the required chemical compounds, thus improving the quality of this class of medicines. PMID:25978064

  3. Thermal-infrared spectra and chemical analyses of twenty-six igneous rock samples

    USGS Publications Warehouse

    Vincent, R.K.; Rowan, L.C.; Gillespie, R.E.; Knapp, C.

    1975-01-01

    Emittance spectra in the 7.5 ??m to 14 ??m wavelength region and chemical compositions of 26 igneous rocks are reported. Experimental measurements on the rocks were made under simulated daytime field conditions. Some surface silicate contaminants, such as clayey silt, significantly altered the spectral emittance of a fresh sample, whereas, for these samples, hydrous and anhydrous ferric oxide weathering products did not mask important silicate spectral information. In the 11.75 ??m to 13.75 ??m wavelength region, the mean emittance of all the silicate samples was 0.956 ?? 0.008, except for periodtite, which had an average emittance of 0.895. This region of uniform emittance should be useful in remote sensing experiments for the separation of the effects of temperature and chemical composition on the spectral emittance of silicate rocks. ?? 1976.

  4. Coordinating Chemical and Mineralogical Analyses of Antarctic Dry Valley Sediments as Potential Analogs for Mars

    NASA Technical Reports Server (NTRS)

    Patel, S. N.; Bishop, J. L.; Englert, P.; Gibson, E. K.

    2015-01-01

    The Antarctic Dry Valleys (ADV) provide a unique terrestrial analog for Martian surface processes as they are extremely cold and dry sedimentary environments. The surface geology and the chemical composition of the Dry Valleys that are similar to Mars suggest the possible presence of these soil-formation processes on Mars. The soils and sediments from Wright Valley, Antarctica were investigated in this study to examine mineralogical and chemical changes along the surface layer in this region and as a function of depth. Surface samples collected near Prospect Mesa and Don Juan Pond of the ADV were analyzed using visible/near-infrared (VNIR) and mid-IR reflectance spectroscopy and major and trace element abundances.

  5. Scalar Relativistic Computations and Localized Orbital Analyses of Nuclear Hyperfine Coupling and Paramagnetic NMR Chemical Shifts

    SciTech Connect

    Aquino, Fredy W.; Pritchard, Ben; Autschbach, Jochen

    2012-02-14

    A method is reported by which calculated hyperfine coupling constants (HFCCs) and paramagnetic NMR (pNMR) chemical shifts can be analyzed in a chemically intuitive way by decomposition into contributions from localized molecular orbitals (LMOs). A new module for density functional calculations with nonhybrid functionals, global hybrids, and range-separated hybrids, utilizing the two-component relativistic zeroth-order regular approximation (ZORA), has been implemented in the parallel open-source NWChem quantum chemistry package. Benchmark results are reported for a test set of few-atom molecules with light and heavy elements. Finite nucleus effects on ¹⁹⁹Hg HFCCs are shown to be on the order of -11 to -15%. A proof of concept for the LMO analysis is provided for the metal and fluorine HFCCs of TiF₃ and NpF₆. Calculated pNMR chemical shifts are reported for the 2-methylphenyl-t-butylnitroxide radical and for five cyclopentadienyl (Cp) sandwich complexes with 3d metals. Nickelocene and vanadocene carbon pNMR shifts are analyzed in detail, demonstrating that the large carbon pNMR shifts calculated as +1540 for Ni (exptl.: +1514) and -443 for V (exptl.: -510) are caused by different spin-polarization mechanisms. For Ni, Cp to Ni π back-donation dominates the result, whereas for vanadocene, V to Cp σ donation with relaxation of the carbon 1s shells can be identified as the dominant mechanism.

  6. Chemical analyses of thermal and nonthermal springs in Lassen Volcanic National Park and vicinity, California

    USGS Publications Warehouse

    Thompson, J.M.

    1983-01-01

    Most thermal waters issuing in Lassen Volcanic National Park (LVNP) are acidic (pH =3.5), low-Cl (concentrations =30 mg/L) hot springs which are characteristic of vapor-dominated hydrothermal systems and, as such, are not useful for liquid chemical geothermometry. Thermal waters at Drakesbad and in Little Hot Springs Valley, hot spring localities characterized by neutral pH and low Cl containing water, may have equilibrated in shallow aquifers so that temperatures estimated by both the Na-K-Ca and Na-Li geothermometers approach the measured spring temperatures of 65? to 95?C. Waters rich in chloride (>2000 mg/L), such as those at Growler Hot Spring and Morgan Hot Springs, situated south of LVNP, are the most appropriate springs for liquid chemical geothermometry and indicate subsurface temperatures between 220? and 230?C. The chemical and thermal characteristics of these springs may result either from boiling at depth and subsequent mixing with meteoric water or from conductive cooling during lateral flow. In either case ~220? to 230?C thermal water probably originates inside LVNP and flows south to Morgan Hot Springs.

  7. Quantitative structure-activity relationship models of chemical transformations from matched pairs analyses.

    PubMed

    Beck, Jeremy M; Springer, Clayton

    2014-04-28

    The concepts of activity cliffs and matched molecular pairs (MMP) are recent paradigms for analysis of data sets to identify structural changes that may be used to modify the potency of lead molecules in drug discovery projects. Analysis of MMPs was recently demonstrated as a feasible technique for quantitative structure-activity relationship (QSAR) modeling of prospective compounds. Although within a small data set, the lack of matched pairs, and the lack of knowledge about specific chemical transformations limit prospective applications. Here we present an alternative technique that determines pairwise descriptors for each matched pair and then uses a QSAR model to estimate the activity change associated with a chemical transformation. The descriptors effectively group similar transformations and incorporate information about the transformation and its local environment. Use of a transformation QSAR model allows one to estimate the activity change for novel transformations and therefore returns predictions for a larger fraction of test set compounds. Application of the proposed methodology to four public data sets results in increased model performance over a benchmark random forest and direct application of chemical transformations using QSAR-by-matched molecular pairs analysis (QSAR-by-MMPA).

  8. Chemical analyses of ground water related to geothermal investigations in the Teton River area, eastern Idaho

    USGS Publications Warehouse

    Crosthwaite, E.G.

    1979-01-01

    Water samples from 31 wells and springs in eastern Idaho and western Wyoming were collected to help evaluate the potential geothermal resources in the Teton River area. Water analyses included anions and cations, oxygen-18, deuterium, and several minor elements. Actual temperature of the thermal waters ranged from 23 to 49C. Estimated aquifer temperatures, as derived from geochemical thermometers, ranged from 45 to 145C based on sodium-potassium-calcium ratios. Using the cation thermometer, two analyses indicated aquifer temperatures lower than actual measured temperatures. Using a mixing model method, estimated temperatures ranged from 205 to 320C, the higher being of questionable value. The different methods used showed little correlation. Based on isotope data, the warm waters may be of local meteoric origin and not heated enough to react significantly with aquifer rocks; or, they originated as precipitation at high altitude and great distance from the area. (Woodard-USGS)

  9. Portable gas chromatograph mass spectrometer for on-site chemical analyses

    DOEpatents

    Haas, Jeffrey S.; Bushman, John F.; Howard, Douglas E.; Wong, James L.; Eckels, Joel D.

    2002-01-01

    A portable, lightweight (approximately 25 kg) gas chromatograph mass spectrometer, including the entire vacuum system, can perform qualitative and quantitative analyses of all sample types in the field. The GC/MS has a conveniently configured layout of components for ease of serviceability and maintenance. The GC/MS system can be transported under operating or near-operating conditions (i.e., under vacuum and at elevated temperature) to reduce the downtime before samples can be analyzed on-site.

  10. Effect of Operating Parameters and Chemical Additives on Crystal Habit and Specific Cake Resistance of Zinc Hydroxide Precipitates

    SciTech Connect

    Alwin, Jennifer Louise

    1999-08-01

    The effect of process parameters and chemical additives on the specific cake resistance of zinc hydroxide precipitates was investigated. The ability of a slurry to be filtered is dependent upon the particle habit of the solid and the particle habit is influenced by certain process variables. The process variables studied include neutralization temperature, agitation type, and alkalinity source used for neutralization. Several commercially available chemical additives advertised to aid in solid/liquid separation were also examined in conjunction with hydroxide precipitation. A statistical analysis revealed that the neutralization temperature and the source of alkalinity were statistically significant in influencing the specific cake resistance of zinc hydroxide precipitates in this study. The type of agitation did not significantly effect the specific cake resistance of zinc hydroxide precipitates. The use of chemical additives in conjunction with hydroxide precipitation had a favorable effect on the filterability. The morphology of the hydroxide precipitates was analyzed using scanning electron microscopy.

  11. Mineralogical and chemical analyses of ancient glass beads from Taiwan and their implications

    NASA Astrophysics Data System (ADS)

    Liou, Y. S.; Liu, Y. C.

    2015-12-01

    Large numbers of monochrome glass beads with different colors, shapes, and stylistics excavated from the archaeological sites of Taiwan, which were dated mainly from the 2nd century AD to the early Historical Period of Taiwan. Archaeologically, these glass beads were more prevalent in eastern and northern Taiwan and were generally believed to be non-native, as well as were brought into Taiwan through the maritime exchange and/or trade activities between Taiwan and Southeast Asia/China since the Neolithic Age. Nevertheless, ancient glass beads have been little studies in Taiwan, aspects of these glass beads are not well detailed. In this work, non-destructive micro-Raman spectroscopy and μXRF are used in combination to examine 56 ancient glass beads excavated from six archaeological sites, eastern Taiwan, to unravel the mineralogical and chemical compositions and to help decipher the raw materials used and the provenance of beads. Micro-Raman measurements indicate the presence of hematite, zincite, siderite, sphalerite, lead tin yellow type II, adularia, chalcedony, anatase, rutite, ankerite, graphite, calcite, etc. Hematite, zincite, siderite, sphalerite, lead tin yellow type II, and rutile were found to be colorants/opacifiers. Among these crystalline phases, lead tin yellow type II was first detected in the ancient glass bead unearthed from Taiwan, which is accordant with results of chemical analysis. The chemical results obtained by μXRF show SiO2, Al2O3, Na2O, K2O, MgO, CaO, and PbO as the most abundant oxides. It is found that Na2O, Na2O, K2O, Al2O3, and MgO are the main/minor fluxes. According to the results, the three most frequent types are mineral soda alumina glass, soda plant ash glass, and lead silicate glass. The provenance of ancient beads unearthed from archaeological sites of Taiwan is possibility of multiple sources.

  12. Chemical analyses for selected wells in San Joaquin County and part of Contra Costa County, California

    USGS Publications Warehouse

    Keeter, Gail L.

    1980-01-01

    The study area of this report includes the eastern valley area of Contra Costa County and all of San Joaquin County, an area of approximately 1,600 square miles in the northern part of the San Joaquin Valley, Calif. Between December 1977 and December 1978, 1,489 wells were selectively canvassed. During May and June in 1978 and 1979, water samples were collected for chemical analysis from 321 of these wells. Field determinations of alkalinity, conductance, pH, and temperature were made, and individual constituents were analyzed. This report is the fourth in a series of baseline data reports on wells in the Sacramento and San Joaquin Valleys. (USGS)

  13. Quantitative proteomic analyses of mammary organoids reveals distinct signatures after exposure to environmental chemicals.

    PubMed

    Williams, Katherine E; Lemieux, George A; Hassis, Maria E; Olshen, Adam B; Fisher, Susan J; Werb, Zena

    2016-03-01

    Common environmental contaminants such as bisphenols and phthalates and persistent contaminants such as polychlorinated biphenyls are thought to influence tissue homeostasis and carcinogenesis by acting as disrupters of endocrine function. In this study we investigated the direct effects of exposure to bisphenol A (BPA), mono-n-butyl phthalate (Pht), and polychlorinated biphenyl 153 (PCB153) on the proteome of primary organotypic cultures of the mouse mammary gland. At low-nanomolar doses each of these agents induced distinct effects on the proteomes of these cultures. Although BPA treatment produced effects that were similar to those induced by estradiol, there were some notable differences, including a reduction in the abundance of retinoblastoma-associated protein and increases in the Rho GTPases Ras-related C3 botulinum toxin substrate 1 (Rac1) and cell division cycle protein CDC42. Both Pht and PCB153 induced changes that were distinct from those induced by estrogen, including decreased levels of the transcriptional corepressor C-terminal binding protein 1. Interestingly, the three chemicals appeared to alter the abundance of distinct splice forms of many proteins as well as the abundance of several proteins that regulate RNA splicing. Our combined results indicate that the three classes of chemical have distinct effects on the proteome of normal mouse mammary cultures, some estrogen-like but most estrogen independent, that influence diverse biological processes including apoptosis, cell adhesion, and proliferation.

  14. Quantitative proteomic analyses of mammary organoids reveals distinct signatures after exposure to environmental chemicals

    PubMed Central

    Williams, Katherine E.; Lemieux, George A.; Hassis, Maria E.; Olshen, Adam B.; Fisher, Susan J.; Werb, Zena

    2016-01-01

    Common environmental contaminants such as bisphenols and phthalates and persistent contaminants such as polychlorinated biphenyls are thought to influence tissue homeostasis and carcinogenesis by acting as disrupters of endocrine function. In this study we investigated the direct effects of exposure to bisphenol A (BPA), mono-n-butyl phthalate (Pht), and polychlorinated biphenyl 153 (PCB153) on the proteome of primary organotypic cultures of the mouse mammary gland. At low-nanomolar doses each of these agents induced distinct effects on the proteomes of these cultures. Although BPA treatment produced effects that were similar to those induced by estradiol, there were some notable differences, including a reduction in the abundance of retinoblastoma-associated protein and increases in the Rho GTPases Ras-related C3 botulinum toxin substrate 1 (Rac1) and cell division cycle protein CDC42. Both Pht and PCB153 induced changes that were distinct from those induced by estrogen, including decreased levels of the transcriptional corepressor C-terminal binding protein 1. Interestingly, the three chemicals appeared to alter the abundance of distinct splice forms of many proteins as well as the abundance of several proteins that regulate RNA splicing. Our combined results indicate that the three classes of chemical have distinct effects on the proteome of normal mouse mammary cultures, some estrogen-like but most estrogen independent, that influence diverse biological processes including apoptosis, cell adhesion, and proliferation. PMID:26903627

  15. Quantitative proteomic analyses of mammary organoids reveals distinct signatures after exposure to environmental chemicals.

    PubMed

    Williams, Katherine E; Lemieux, George A; Hassis, Maria E; Olshen, Adam B; Fisher, Susan J; Werb, Zena

    2016-03-01

    Common environmental contaminants such as bisphenols and phthalates and persistent contaminants such as polychlorinated biphenyls are thought to influence tissue homeostasis and carcinogenesis by acting as disrupters of endocrine function. In this study we investigated the direct effects of exposure to bisphenol A (BPA), mono-n-butyl phthalate (Pht), and polychlorinated biphenyl 153 (PCB153) on the proteome of primary organotypic cultures of the mouse mammary gland. At low-nanomolar doses each of these agents induced distinct effects on the proteomes of these cultures. Although BPA treatment produced effects that were similar to those induced by estradiol, there were some notable differences, including a reduction in the abundance of retinoblastoma-associated protein and increases in the Rho GTPases Ras-related C3 botulinum toxin substrate 1 (Rac1) and cell division cycle protein CDC42. Both Pht and PCB153 induced changes that were distinct from those induced by estrogen, including decreased levels of the transcriptional corepressor C-terminal binding protein 1. Interestingly, the three chemicals appeared to alter the abundance of distinct splice forms of many proteins as well as the abundance of several proteins that regulate RNA splicing. Our combined results indicate that the three classes of chemical have distinct effects on the proteome of normal mouse mammary cultures, some estrogen-like but most estrogen independent, that influence diverse biological processes including apoptosis, cell adhesion, and proliferation. PMID:26903627

  16. Combining hydraulic model, hydrogeomorphological observations and chemical analyses of surface waters to improve knowledge on karst flash floods genesis

    NASA Astrophysics Data System (ADS)

    Raynaud, F.; Borrell-Estupina, V.; Pistre, S.; Van-Exter, S.; Bourgeois, N.; Dezetter, A.; Servat, E.

    2015-06-01

    During a flood event over a karst watershed, the connections between surface and ground waters appear to be complex ones. The karst may attenuate surface floods by absorbing water or contribute to the surface flood by direct contribution of karst waters in the rivers (perennial and overflowing springs) and by diffuse resurgence along the hillslopes. If it is possible to monitor each known outlet of a karst system, the diffuse contribution is yet difficult to assess. Furthermore, all these connections vary over time according to several factors such as the water content of the soil and underground, the rainfall characteristics, the runoff pathways. Therefore, the contribution of each compartment is generally difficult to assess, and flood dynamics are not fully understood. To face these misunderstandings and difficulties, we analysed surface waters during six recent flood events in the Lirou watershed (a karst tributary of the Lez, in South of France). Because of the specific chemical signature of karst waters, chemical analyses can supply information about water pathways and flood dynamics. Then, we used the dilution law to combine chemical results, flow data and field observations to assess the dynamics of the karst component of the flood. To end, we discussed the surface or karst origin of the waters responsible for the apparent runoff coefficient rise during flash karst flood.

  17. Combination of chemical analyses and animal feeding trials as reliable procedures to assess the safety of heat processed soybean seeds.

    PubMed

    Vasconcelos, Ilka M; Brasil, Isabel Cristiane F; Oliveira, José Tadeu A; Campello, Cláudio C; Maia, Fernanda Maria M; Campello, Maria Verônica M; Farias, Davi F; Carvalho, Ana Fontenele U

    2009-06-10

    This study assessed whether chemical analyses are sufficient to guarantee the safety of heat processing of soybeans (SB) for human/animal consumption. The effects of extrusion and dry-toasting were analyzed upon seed composition and performance of broiler chicks. None of these induced appreciable changes in protein content and amino acid composition. Conversely, toasting reduced all antinutritional proteins by over 85%. Despite that, the animals fed on toasted SB demonstrated a low performance (feed efficiency 57.8 g/100 g). Extrusion gave place to higher contents of antinutrients, particularly of trypsin inhibitors (27.53 g/kg flour), but animal performance was significantly (p < 0.05) better (feed efficiency 63.2 g/100 g). Upon the basis of chemical analyses, dry-toasting represents the treatment of choice. However, considering the results of the feeding trials, extrusion appears to be the safest method. In conclusion, in order to evaluate the reliability of any processing method intended to improve nutritional value, the combination of chemical and animal studies is necessary.

  18. USING DOSE ADDITION TO ESTIMATE CUMULATIVE RISKS FROM EXPOSURES TO MULTIPLE CHEMICALS

    EPA Science Inventory

    The Food Quality Protection Act (FQPA) of 1996 requires the EPA to consider the cumulative risk from exposure to multiple chemicals that have a common mechanism of toxicity. Three methods, hazard index (HI), point-of-departure index (PODI), and toxicity equivalence factor (TEF), ...

  19. 75 FR 72727 - Addition of National Toxicology Program Carcinogens; Community Right-to-Know Toxic Chemical...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-26

    ... emissions from vegetation, particularly from deciduous forests. The commenter cited sources that state that... criterion.'' EPA has published in the Federal Register of November 30, 1994 (59 FR 61432) a statement... EPCRA section 313 list of toxic chemicals? As discussed in the proposed rule (75 FR 17333, April 6,...

  20. Hanford Environmental Restoration data validation process for chemical and radiochemical analyses

    SciTech Connect

    Adams, M.R.; Bechtold, R.A.; Clark, D.E.; Angelos, K.M.; Winter, S.M.

    1993-10-01

    Detailed procedures for validation of chemical and radiochemical data are used to assure consistent application of validation principles and support a uniform database of quality environmental data. During application of these procedures, it was determined that laboratory data packages were frequently missing certain types of documentation causing subsequent delays in meeting critical milestones in the completion of validation activities. A quality improvement team was assembled to address the problems caused by missing documentation and streamline the entire process. The result was the development of a separate data package verification procedure and revisions to the data validation procedures. This has resulted in a system whereby deficient data packages are immediately identified and corrected prior to validation and revised validation procedures which more closely match the common analytical reporting practices of laboratory service vendors.

  1. QUALITY ASSURANCE PROGRAM FOR WET DEPOSITION SAMPLING AND CHEMICAL ANALYSES FOR THE NATIONAL TRENDS NETWORK.

    USGS Publications Warehouse

    Schroder, LeRoy J.; Malo, Bernard A.; ,

    1985-01-01

    The purpose of the National Trends Network is to delineate the major inorganic constituents in the wet deposition in the United States. The approach chosen to monitor the Nation's wet deposition is to install approximately 150 automatic sampling devices with at least one collector in each state. Samples are collected at one week intervals, removed from collectors, and transported to an analytical laboratory for chemical analysis. The quality assurance program has divided wet deposition monitoring into 5 parts: (1) Sampling site selection, (2) sampling device, (3) sample container, (4) sample handling, and (5) laboratory analysis. Each of these five components is being examined using existing designs or new designs. Each existing or proposed sampling site is visited and a criteria audit is performed.

  2. An assessment of endocrine activity in Australian rivers using chemical and in vitro analyses.

    PubMed

    Scott, Philip D; Bartkow, Michael; Blockwell, Stephen J; Coleman, Heather M; Khan, Stuart J; Lim, Richard; McDonald, James A; Nice, Helen; Nugegoda, Dayanthi; Pettigrove, Vincent; Tremblay, Louis A; Warne, Michael St J; Leusch, Frederic D L

    2014-11-01

    Studies on endocrine disruption in Australia have mainly focused on wastewater effluents. Limited knowledge exists regarding the relative contribution of different potential sources of endocrine active compounds (EACs) to the aquatic environment (e.g., pesticide run-off, animal farming operations, urban stormwater, industrial inputs). In this study, 73 river sites across mainland Australia were sampled quarterly for 1 year. Concentrations of 14 known EACs including natural and synthetic hormones and industrial compounds were quantified by chemical analysis. EACs were detected in 88 % of samples (250 of 285) with limits of quantification (LOQ) ranging from 0.05 to 20 ng/l. Bisphenol A (BPA; LOQ = 20 ng/l) was the most frequently detected EAC (66 %) and its predicted no-effect concentration (PNEC) was exceeded 24 times. The most common hormone was estrone, detected in 28 % of samples (LOQ = 1 ng/l), and the PNEC was also exceeded 24 times. 17α-Ethinylestradiol (LOQ = 0.05 ng/l) was detected in 10 % of samples at concentrations ranging from 0.05 to 0.17 ng/l. It was detected in many samples with no wastewater influence, and the PNEC was exceeded 13 times. In parallel to the chemical analysis, endocrine activity was assessed using a battery of CALUX bioassays. Estrogenic activity was detected in 19 % (53 of 285) of samples (LOQ = 0.1 ng/l 17β-estradiol equivalent; EEQ). Seven samples exhibited estrogenic activity (1-6.5 ng/l EEQ) greater than the PNEC for 17β-estradiol. Anti-progestagenic activity was detected in 16 % of samples (LOQ = 8 ng/l mifepristone equivalents; MifEQ), but the causative compounds are unknown. With several compounds and endocrine activity exceeding PNEC values, there is potential risk to the Australian freshwater ecosystems.

  3. Detection and characterisation of frauds in bovine meat in natura by non-meat ingredient additions using data fusion of chemical parameters and ATR-FTIR spectroscopy.

    PubMed

    Nunes, Karen M; Andrade, Marcus Vinícius O; Santos Filho, Antônio M P; Lasmar, Marcelo C; Sena, Marcelo M

    2016-08-15

    Concerns about meat authenticity are increasing recently, due to great fraud scandals. This paper analysed real samples (43 adulterated and 12 controls) originated from criminal networks dismantled by the Brazilian Police. This fraud consisted of injecting solutions of non-meat ingredients (NaCl, phosphates, carrageenan, maltodextrin) in bovine meat, aiming to increase its water holding capacity. Five physico-chemical variables were determined, protein, ash, chloride, sodium, phosphate. Additionally, infrared spectra were recorded. Supervised classification PLS-DA models were built with each data set individually, but the best model was obtained with data fusion, correctly detecting 91% of the adulterated samples. From this model, a variable selection based on the highest VIPscores was performed and a new data fusion model was built with only one chemical variable, providing slightly lower predictions, but a good cost/performance ratio. Finally, some of the selected infrared bands were specifically associated to the presence of adulterants NaCl, tripolyphosphate and carrageenan.

  4. Chemical analyses and K-Ar ages of samples from 13 drill holes, Medicine Lake volcano, California

    USGS Publications Warehouse

    Donnelly-Nolan, Julie M.

    2006-01-01

    This report presents chemical analyses and K-Ar ages obtained from drill hole samples studied in support of geologic mapping at Medicine Lake volcano (MLV), northern California. The holes were drilled by private companies exploring for geothermal energy at the volcano. Drill core and cuttings were later made available for study; core is stored at the Energy and Geoscience Institute (EGI) warehouse in Salt Lake City, Utah. Discussion of the significance of the chemical and age data will be presented elsewhere, although it is apparent from the cross-section and from Table 1 that a large percentage of MLV core consists of rocks with more than 63 percent SiO2.

  5. Development of site-specific sediment no-effect concentrations based on synoptic chemical analyses and toxicity testing

    SciTech Connect

    Sferra, J.; Barber, T.; Fuchsman, P.; Sheehan, P.

    1995-12-31

    Site-specific maximum observed no-effect concentrations (MONECs) were developed using sediment chemistry and toxicity test data concomitantly collected from 33 sample locations in a river system adjacent to a RCRA facility in Ohio. Physical and chemical analyses included VOCs, SVOCs, metals, pesticides and PCBs, acid volatile sulfides and simultaneously extracted metals, ammonia, total organic carbon and grain size. Concentrations of hydrophobic, non-polar organic compounds were normalized to 1% total organic carbon contents, as the bioavailability of these compounds was considered to be primarily controlled by sediment organic carbon content through adsorption. Toxicity tests conducted using Chironomus tentans and Hyalella azteca were analyzed for impacts to survival and growth endpoints for both species. Samples were separated into two categories for each test endpoint, depending on whether toxicity was observed. MONECs were defined as the highest measured chemical concentration that did not produce a significant effect in toxicity tests. MONEC values were derived for each species and test endpoint, and the lowest of these four values was adopted as the site-specific MONEC for each chemical. Site-specific MONECs were used as a tool to assist in the identification of chemicals contributing to observed sediment toxicity.

  6. The Effects of Chemical Wash Additives on the Corrosion of Aerospace Alloys in Marine Environments

    NASA Technical Reports Server (NTRS)

    MacDowell, Louis; Calle, Luz Marina; Curran, Joseph; Hodge, Tim; Barile, Ronald; Heidersbach, Robert; Steinrock, T. (Technical Monitor)

    2002-01-01

    This paper presents the methodology for comparing the relative effectiveness of four chemical products used for rinsing airplanes and helicopters. The products were applied on a weekly basis to a series of flat alloy panels exposed to an oceanfront marine environment for one year. The results are presented along with comparisons of exposures of the same alloys that were not washed, were washed with seawater, or washed with de-ionized water.

  7. Nutrient intake and health status of vegans. Chemical analyses of diets using the duplicate portion sampling technique.

    PubMed

    Abdulla, M; Andersson, I; Asp, N G; Berthelsen, K; Birkhed, D; Dencker, I; Johansson, C G; Jägerstad, M; Kolar, K; Nair, B M; Nilsson-Ehle, P; Nordén, A; Rassner, S; Akesson, B; Ockerman, P A

    1981-11-01

    A strict vegetarian diet [vegan diet (VD)] was investigated. Six middle-aged vegans (three men and three women) collected copies of 24-h diets using the duplicate portion sampling technique. By chemical analyses, the nutrient composition was determined in detail and compared with corresponding figures of a normal mixed Swedish diet. In the VD 30% of the energy originated from fat compared with 40% in normal Swedish mixed diet (MD). Linoleic acid was the dominant fatty acid (60% of total fat in VD versus 8% in MD). The VD contained 24 g protein/1000 kcal compared to 30 g/1000 kcal in MD, but the intake of essential amino acids by the vegans exceeded the recommendations. Dietary fiber was about 5 times higher in the vegan diet (29 versus 6 g/1000 kcal) and sucrose similar to MD (18 versus 21 g/1000 kcal). Among the inorganic nutrients the concentration of calcium (351 versus 391 mg/1000 kcal) and sodium (53 versus 49 mmol/1000 kcal) were similar in both types of diets but the amount of potassium (56 versus 30 mmol/1000 kcal, magnesium (300 versus 110 mg/1000 kcal), iron (9 versus 6.5 mg/1000 kcal), zinc (6.5 versus 4.7 mg/1000 kcal), and copper (2 versus 0.7 mg/1000 kcal) were nearly doubled. Iodine (39 versus 156 micrograms/1000 kcal and selenium (5 versus 17 micrograms/1000 kcal) were much lower in the VD, selenium even being undetectable in several 24-h diets. The VD was rich in folic acid (301 versus 90 micrograms/1000 kcal in MD) but the intake of vitamin B12 was only 0.3 to 0.4 microgram/day (MD: 3 to 4 micrograms/day). No clinical signs of nutritional deficiency were observed in the vegans. Serum protein levels of the vegans as well as their serum lipoproteins were near the lower range of the reference group. In addition, none of the vegans was overweight and their blood pressures were low for their age.

  8. Particle size distribution and chemical composition of total mixed rations for dairy cattle: water addition and feed sampling effects.

    PubMed

    Arzola-Alvarez, C; Bocanegra-Viezca, J A; Murphy, M R; Salinas-Chavira, J; Corral-Luna, A; Romanos, A; Ruíz-Barrera, O; Rodríguez-Muela, C

    2010-09-01

    Four dairy farms were used to determine the effects of water addition to diets and sample collection location on the particle size distribution and chemical composition of total mixed rations (TMR). Samples were collected weekly from the mixing wagon and from 3 locations in the feed bunk (top, middle, and bottom) for 5 mo (April, May, July, August, and October). Samples were partially dried to determine the effect of moisture on particle size distribution. Particle size distribution was measured using the Penn State Particle Size Separator. Crude protein, neutral detergent fiber, and acid detergent fiber contents were also analyzed. Particle fractions 19 to 8, 8 to 1.18, and <1.18 mm were judged adequate in all TMR for rumen function and milk yield; however, the percentage of material>19 mm was greater than recommended for TMR, according to the guidelines of Cooperative Extension of Pennsylvania State University. The particle size distribution in April differed from that in October, but intermediate months (May, July, and August) had similar particle size distributions. Samples from the bottom of the feed bunk had the highest percentage of particles retained on the 19-mm sieve. Samples from the top and middle of the feed bunk were similar to that from the mixing wagon. Higher percentages of particles were retained on >19, 19 to 8, and 8 to 1.18 mm sieves for wet than dried samples. The reverse was found for particles passing the 1.18-mm sieve. Mean particle size was higher for wet than dried samples. The crude protein, neutral detergent fiber, and acid detergent fiber contents of TMR varied with month of sampling (18-21, 40-57, and 21-34%, respectively) but were within recommended ranges for high-yielding dairy cows. Analyses of TMR particle size distributions are useful for proper feed bunk management and formulation of diets that maintain rumen function and maximize milk production and quality. Water addition may help reduce dust associated with feeding TMR. PMID

  9. Chemical and biological consequences of using carbon dioxide versus acid additions in ocean acidification experiments

    USGS Publications Warehouse

    Yates, Kimberly K.; DuFore, Christopher M.; Robbins, Lisa L.

    2013-01-01

    Use of different approaches for manipulating seawater chemistry during ocean acidification experiments has confounded comparison of results from various experimental studies. Some of these discrepancies have been attributed to whether addition of acid (such as hydrochloric acid, HCl) or carbon dioxide (CO2) gas has been used to adjust carbonate system parameters. Experimental simulations of carbonate system parameter scenarios for the years 1766, 2007, and 2100 were performed using the carbonate speciation program CO2SYS to demonstrate the variation in seawater chemistry that can result from use of these approaches. Results showed that carbonate system parameters were 3 percent and 8 percent lower than target values in closed-system acid additions, and 1 percent and 5 percent higher in closed-system CO2 additions for the 2007 and 2100 simulations, respectively. Open-system simulations showed that carbonate system parameters can deviate by up to 52 percent to 70 percent from target values in both acid addition and CO2 addition experiments. Results from simulations for the year 2100 were applied to empirically derived equations that relate biogenic calcification to carbonate system parameters for calcifying marine organisms including coccolithophores, corals, and foraminifera. Calculated calcification rates for coccolithophores, corals, and foraminifera differed from rates at target conditions by 0.5 percent to 2.5 percent in closed-system CO2 gas additions, from 0.8 percent to 15 percent in the closed-system acid additions, from 4.8 percent to 94 percent in open-system acid additions, and from 7 percent to 142 percent in open-system CO2 additions.

  10. Comparative chemical analyses of soils formed on carbonate rocks in Hungary

    NASA Astrophysics Data System (ADS)

    Németh, Eszter; Sajó, István; Bidló, András

    2014-05-01

    The present study focuses on the physical and chemical investigation of soils formed primarily on carbonate rocks. One part of the investigated soil profiles originated from the top of the Bükk Hills, the Bükk-Highlands' limestone plateau, which is located in the North-Eastern part of Hungary. The rest of the samples were taken from the Szárhalom Forest (located in West Hungary). The different location and climate of the sites forms a basis of the comparison of the soils with similar base rock. These soils are formed mainly on limestones, however they differ significantly in terms of certain characteristic properties. The following physical parameters were evaluated from the samples: transition, structure, compactness, roots, skeletal percent, colour, physical assortment, concretion and soil defect. Laboratory analysis involved the measurement of acidity, particle distribution, carbonated lime content, humus content, ammonium lactate-acetic acid soluble phosphorus- and potassium content, potassium chloride soluble calcium- and magnesium content, ethylene-diamine-tetraacetic-acid (EDTA) and diethylene-triamine-pentaacetic-acid (DTPA) soluble copper-, iron-, manganese- and zinc content. X-ray diffraction, thermoanalytical measurements and ICP-OES were also carried out to determine the mineral composition of the soils and the content of heavy metals. Evaluation focused on the comprehensive analysis of the data with a special regard to possible relationships and correlations. Research was supported financially by the "Silva naturalis (TÁMOP-4.2.2.A-11/1/KONV-2012-0004)" project.

  11. New insights in quantum chemical topology studies using numerical grid-based analyses.

    PubMed

    Kozlowski, David; Pilmé, Julien

    2011-11-30

    New insights in Quantum Chemical Topology of one-electron density functions have been proposed here by using a recent grid-based algorithm (Tang et al., J Phys Condens Matter 2009, 21, 084204), initially designed for the decomposition of the electron density. Beyond the charge analysis, we show that this algorithm is suitable for different scalar functions showing a more complex topology, that is, the Laplacian of the electron density, the electron localization function (ELF), and the molecular electrostatic potential (MEP). This algorithm makes use of a robust methodology enabling to numerically assign the data points of three-dimensional grids to basin volumes, and it has the advantage of requiring only the values of the scalar function without details on the wave function used to build the grid. Our implementation is briefly outlined (program named TopChem), its capabilities are examined, and technical aspects in terms of CPU requirement and accuracy of the results are discussed. Illustrative examples for individual molecules and crystalline solids obtained with gaussian and plane-wave-based density functional theory calculations are presented. Special attention was given to the MEP because its topological analysis is complex and scarce.

  12. Qualitative/Chemical Analyses of Ankaferd Hemostat and Its Antioxidant Content in Synthetic Gastric Fluids

    PubMed Central

    Koluman, Ahmet; Akar, Nejat; Malkan, Umit Y.; Haznedaroglu, Ibrahim C.

    2016-01-01

    Introduction. Ankaferd hemostat (ABS) is the first topical haemostatic agent involving the red blood cell-fibrinogen interactions. The antihemorrhagic efficacy of ABS has been tested in controlled clinical trials. The drug induces the formation of an encapsulated complex protein web with vital erythroid aggregation. The aim of this study is to detect the essential toxicity profile and the antioxidant molecules inside ABS. Methods. The pesticides were analyzed by GC-MS and LC-MS. The determination by ICP-MS after pressure digestion was performed for the heavy metals. HPLC was used for the detection of mycotoxins. Dioxin Response Chemically Activated Luciferase Gene Expression method was used for the dioxin evaluation. TOF-MS and spectra data were evaluated to detect the antioxidants and other molecules. Results. TOF-MS spectra revealed the presence of several antioxidant molecules (including tocotrienols, vitamin E, tryptophan, estriol, galangin, apigenin, oenin, 3,4-divanillyltetrahydrofuran, TBHQ, thymol, BHA, BHT, lycopene, glycyrrhetinic acid, and tomatine), which may have clinical implications in the pharmacobiological actions of ABS. Conclusion. The safety of ABS regarding the presence of heavy metals, pesticides, mycotoxins, GMO and dioxins, and PCBs was demonstrated. Thus the present toxicological results indicated the safety of ABS. The antioxidant content of ABS should be investigated in future studies. PMID:26925418

  13. The effect of chemical additives on the synthesis of ethanol. Technical progress report 5, September 16, 1988--December 15, 1988

    SciTech Connect

    Chuang, S.S.C.

    1989-02-04

    The objective of this research is to elucidate the role of various chemical additives on ethanol synthesis over Rh- and Ni-based catalysts. Chemical additives used will include S, P, Ag, Cu, Mn, and Na. The effect of additives on the surface state of the catalysts, heat of adsorption of reactant molecules, reaction intermediates, reaction pathways, reaction kinetics, and product distributions is/will be investigated by a series of studies including temperature programmed desorption, infrared study of NO adsorption, reactive probing, steady state rate measurement, and transient kinetic study. A better understanding of the role of additive may allow us to use chemical additives to manipulate the catalytic properties of Rh- and Ni-based catalysts for producing high yields of ethanol from syngas. CO insertion is known to be a key step to the formation of acetaldehyde and ethanol from CO hydrogenation over Rh catalysts. Ethylene hydroformylation has often served as a probe to determine CO insertion capabilities of Rh catalysts. The mechanism of CO insertion in ethylene hydroformylation over Rh/SiO{sub 2} was investigated.

  14. Analysing the health effects of simultaneous exposure to physical and chemical properties of airborne particles

    PubMed Central

    Pirani, Monica; Best, Nicky; Blangiardo, Marta; Liverani, Silvia; Atkinson, Richard W.; Fuller, Gary W.

    2015-01-01

    Background Airborne particles are a complex mix of organic and inorganic compounds, with a range of physical and chemical properties. Estimation of how simultaneous exposure to air particles affects the risk of adverse health response represents a challenge for scientific research and air quality management. In this paper, we present a Bayesian approach that can tackle this problem within the framework of time series analysis. Methods We used Dirichlet process mixture models to cluster time points with similar multipollutant and response profiles, while adjusting for seasonal cycles, trends and temporal components. Inference was carried out via Markov Chain Monte Carlo methods. We illustrated our approach using daily data of a range of particle metrics and respiratory mortality for London (UK) 2002–2005. To better quantify the average health impact of these particles, we measured the same set of metrics in 2012, and we computed and compared the posterior predictive distributions of mortality under the exposure scenario in 2012 vs 2005. Results The model resulted in a partition of the days into three clusters. We found a relative risk of 1.02 (95% credible intervals (CI): 1.00, 1.04) for respiratory mortality associated with days characterised by high posterior estimates of non-primary particles, especially nitrate and sulphate. We found a consistent reduction in the airborne particles in 2012 vs 2005 and the analysis of the posterior predictive distributions of respiratory mortality suggested an average annual decrease of − 3.5% (95% CI: − 0.12%, − 5.74%). Conclusions We proposed an effective approach that enabled the better understanding of hidden structures in multipollutant health effects within time series analysis. It allowed the identification of exposure metrics associated with respiratory mortality and provided a tool to assess the changes in health effects from various policies to control the ambient particle matter mixtures. PMID:25795926

  15. Effect of the Addition of Schisandra chinensis Powder on the Physico-chemical Characteristics of Sausage.

    PubMed

    Jin, S K; Park, J H

    2013-12-01

    The individual and interactive effects of Schisandra chinensis powder (SCP) and sodium nitrite additions on color, pH, water holding capacity, residual nitrite, 2-thiobarbituric acid reactive substances (TBARS), volatile basic nitrogen, texture properties, fatty acids, amino acids and sensory evaluation of cooked pork sausages were investigated after 20 d of storage at 4°C. The powders (0, 0.5 and 1.0%) were added to sausages either alone or in combination with nitrite (0 and 100 ppm). SCP added-sausages showed lower L* (lightness) and W (whiteness) values, and higher b* (yellowness) values than sausage containing no nitrite, and exhibited the highest a(*) values at a 0.5% addition (p<0.05). Residual nitrite and TBARS values were found to be significantly reduced as the addition levels of SCP increased (p<0.05). As the addition of SCP increased, the sausage showed gradually decreased brittleness, cohesiveness, springiness, gumminess and chewiness, while adhesiveness increased. Polyunsaturated fatty acid, n-6 and n-6/n-3 fatty acid ratio concentrations were significantly higher in sausages containing SCP (p<0.05). The addition of SCP to sausage significantly (p<0.05) increased the ammonia content (by 0.5% SCP) and aromatic amino acid concentrations (by 1.0% SCP) (p<0.05). Inclusion of SCP in sausage meat resulted in a significant deterioration in quality characteristics of flavor, springiness, juiciness and overall acceptability (p<0.05). As expected, the observed changes in a*, W, pH, shear force, texture property, TBARS, fatty acid, amino acid and sensory score of sausages, depended on the rate of addition of nitrite (p<0.05). These results suggest that SCP addition is not an effective way of improving the sensory evaluation of sausages, but may beneficially affect TBARS, nitrite scavenging activity, fatty acid and amino acid content in pork sausages.

  16. Effect of the Addition of Schisandra chinensis Powder on the Physico-chemical Characteristics of Sausage

    PubMed Central

    Jin, S. K.; Park, J. H.

    2013-01-01

    The individual and interactive effects of Schisandra chinensis powder (SCP) and sodium nitrite additions on color, pH, water holding capacity, residual nitrite, 2-thiobarbituric acid reactive substances (TBARS), volatile basic nitrogen, texture properties, fatty acids, amino acids and sensory evaluation of cooked pork sausages were investigated after 20 d of storage at 4°C. The powders (0, 0.5 and 1.0%) were added to sausages either alone or in combination with nitrite (0 and 100 ppm). SCP added-sausages showed lower L* (lightness) and W (whiteness) values, and higher b* (yellowness) values than sausage containing no nitrite, and exhibited the highest a* values at a 0.5% addition (p<0.05). Residual nitrite and TBARS values were found to be significantly reduced as the addition levels of SCP increased (p<0.05). As the addition of SCP increased, the sausage showed gradually decreased brittleness, cohesiveness, springiness, gumminess and chewiness, while adhesiveness increased. Polyunsaturated fatty acid, n-6 and n-6/n-3 fatty acid ratio concentrations were significantly higher in sausages containing SCP (p<0.05). The addition of SCP to sausage significantly (p<0.05) increased the ammonia content (by 0.5% SCP) and aromatic amino acid concentrations (by 1.0% SCP) (p<0.05). Inclusion of SCP in sausage meat resulted in a significant deterioration in quality characteristics of flavor, springiness, juiciness and overall acceptability (p<0.05). As expected, the observed changes in a*, W, pH, shear force, texture property, TBARS, fatty acid, amino acid and sensory score of sausages, depended on the rate of addition of nitrite (p<0.05). These results suggest that SCP addition is not an effective way of improving the sensory evaluation of sausages, but may beneficially affect TBARS, nitrite scavenging activity, fatty acid and amino acid content in pork sausages. PMID:25049766

  17. Evaluation of the protective effect of chemical additives in the oxidation of phenolic compounds catalysed by peroxidase.

    PubMed

    Torres, Juliana Arriel; Chagas, Pricila Maria Batista; Silva, Maria Cristina; Dos Santos, Custódio Donizete; Corrêa, Angelita Duarte

    2016-01-01

    The use of oxidoredutive enzymes in removing organic pollutants has been the subject of much research. The oxidation of phenolic compounds in the presence of chemical additives has been the focus of this study. In this investigation, the influence of the additives polyethylene glycol and Triton X-100 was evaluated in the phenol oxidation, caffeic acid, chlorogenic acid and total phenolic compounds present in coffee processing wastewater (CPW) at different pH values, performed by turnip peroxidase and peroxidase extracted from soybean seed hulls. The influence of these additives was observed only in the oxidation of phenol and caffeic acid. In the oxidation of other studied phenolic compounds, the percentage of oxidation remained unchanged in the presence of these chemical additives. In the oxidation of CPW in the presence of additives, no change in the oxidation of phenolic compounds was observed. Although several studies show the importance of evaluating the influence of additives on the behaviour of enzymes, this study found a positive response from the economic point of view for the treatment of real wastewater, since the addition of these substances showed no influence on the oxidation of phenolic compounds, which makes the process less costly.

  18. Evaluation of the protective effect of chemical additives in the oxidation of phenolic compounds catalysed by peroxidase.

    PubMed

    Torres, Juliana Arriel; Chagas, Pricila Maria Batista; Silva, Maria Cristina; Dos Santos, Custódio Donizete; Corrêa, Angelita Duarte

    2016-01-01

    The use of oxidoredutive enzymes in removing organic pollutants has been the subject of much research. The oxidation of phenolic compounds in the presence of chemical additives has been the focus of this study. In this investigation, the influence of the additives polyethylene glycol and Triton X-100 was evaluated in the phenol oxidation, caffeic acid, chlorogenic acid and total phenolic compounds present in coffee processing wastewater (CPW) at different pH values, performed by turnip peroxidase and peroxidase extracted from soybean seed hulls. The influence of these additives was observed only in the oxidation of phenol and caffeic acid. In the oxidation of other studied phenolic compounds, the percentage of oxidation remained unchanged in the presence of these chemical additives. In the oxidation of CPW in the presence of additives, no change in the oxidation of phenolic compounds was observed. Although several studies show the importance of evaluating the influence of additives on the behaviour of enzymes, this study found a positive response from the economic point of view for the treatment of real wastewater, since the addition of these substances showed no influence on the oxidation of phenolic compounds, which makes the process less costly. PMID:26502790

  19. Landfill mining: Resource potential of Austrian landfills--Evaluation and quality assessment of recovered municipal solid waste by chemical analyses.

    PubMed

    Wolfsberger, Tanja; Aldrian, Alexia; Sarc, Renato; Hermann, Robert; Höllen, Daniel; Budischowsky, Andreas; Zöscher, Andreas; Ragoßnig, Arne; Pomberger, Roland

    2015-11-01

    Since the need for raw materials in countries undergoing industrialisation (like China) is rising, the availability of metal and fossil fuel energy resources (like ores or coal) has changed in recent years. Landfill sites can contain considerable amounts of recyclables and energy-recoverable materials, therefore, landfill mining is an option for exploiting dumped secondary raw materials, saving primary sources. For the purposes of this article, two sanitary landfill sites have been chosen for obtaining actual data to determine the resource potential of Austrian landfills. To evaluate how pretreating waste before disposal affects the resource potential of landfills, the first landfill site has been selected because it has received untreated waste, whereas mechanically-biologically treated waste was dumped in the second. The scope of this investigation comprised: (1) waste characterisation by sorting analyses of recovered waste; and (2) chemical analyses of specific waste fractions for quality assessment regarding potential energy recovery by using it as solid recovered fuels. The content of eight heavy metals and the net calorific values were determined for the chemical characterisation tests. PMID:26347181

  20. Long-term fertilization alters chemically-separated soil organic carbon pools: Based on stable C isotope analyses.

    PubMed

    Dou, Xiaolin; He, Ping; Cheng, Xiaoli; Zhou, Wei

    2016-01-01

    Quantification of dynamics of soil organic carbon (SOC) pools under the influence of long-term fertilization is essential for predicting carbon (C) sequestration. We combined soil chemical fractionation with stable C isotope analyses to investigate the C dynamics of the various SOC pools after 25 years of fertilization. Five types of soil samples (0-20, 20-40 cm) including the initial level (CK) and four fertilization treatments (inorganic nitrogen fertilizer, IN; balanced inorganic fertilizer, NPK; inorganic fertilizer plus farmyard manure, MNPK; inorganic fertilizer plus corn straw residue, SNPK) were separated into recalcitrant and labile fractions, and the fractions were analysed for C content, C:N ratios, δ(13)C values, soil C and N recalcitrance indexes (RIC and RIN). Chemical fractionation showed long-term MNPK fertilization strongly increased the SOC storage in both soil layers (0-20 cm = 1492.4 gC m(2) and 20-40 cm = 1770.6 gC m(2)) because of enhanced recalcitrant C (RC) and labile C (LC). The 25 years of inorganic fertilizer treatment did not increase the SOC storage mainly because of the offsetting effects of enhanced RC and decreased LC, whereas no clear SOC increases under the SNPK fertilization resulted from the fast decay rates of soil C. PMID:26750143

  1. Landfill mining: Resource potential of Austrian landfills--Evaluation and quality assessment of recovered municipal solid waste by chemical analyses.

    PubMed

    Wolfsberger, Tanja; Aldrian, Alexia; Sarc, Renato; Hermann, Robert; Höllen, Daniel; Budischowsky, Andreas; Zöscher, Andreas; Ragoßnig, Arne; Pomberger, Roland

    2015-11-01

    Since the need for raw materials in countries undergoing industrialisation (like China) is rising, the availability of metal and fossil fuel energy resources (like ores or coal) has changed in recent years. Landfill sites can contain considerable amounts of recyclables and energy-recoverable materials, therefore, landfill mining is an option for exploiting dumped secondary raw materials, saving primary sources. For the purposes of this article, two sanitary landfill sites have been chosen for obtaining actual data to determine the resource potential of Austrian landfills. To evaluate how pretreating waste before disposal affects the resource potential of landfills, the first landfill site has been selected because it has received untreated waste, whereas mechanically-biologically treated waste was dumped in the second. The scope of this investigation comprised: (1) waste characterisation by sorting analyses of recovered waste; and (2) chemical analyses of specific waste fractions for quality assessment regarding potential energy recovery by using it as solid recovered fuels. The content of eight heavy metals and the net calorific values were determined for the chemical characterisation tests.

  2. Long-term fertilization alters chemically-separated soil organic carbon pools: Based on stable C isotope analyses

    NASA Astrophysics Data System (ADS)

    Dou, Xiaolin; He, Ping; Cheng, Xiaoli; Zhou, Wei

    2016-01-01

    Quantification of dynamics of soil organic carbon (SOC) pools under the influence of long-term fertilization is essential for predicting carbon (C) sequestration. We combined soil chemical fractionation with stable C isotope analyses to investigate the C dynamics of the various SOC pools after 25 years of fertilization. Five types of soil samples (0–20, 20–40 cm) including the initial level (CK) and four fertilization treatments (inorganic nitrogen fertilizer, IN; balanced inorganic fertilizer, NPK; inorganic fertilizer plus farmyard manure, MNPK; inorganic fertilizer plus corn straw residue, SNPK) were separated into recalcitrant and labile fractions, and the fractions were analysed for C content, C:N ratios, δ13C values, soil C and N recalcitrance indexes (RIC and RIN). Chemical fractionation showed long-term MNPK fertilization strongly increased the SOC storage in both soil layers (0–20 cm = 1492.4 gC m2 and 20–40 cm = 1770.6 gC m2) because of enhanced recalcitrant C (RC) and labile C (LC). The 25 years of inorganic fertilizer treatment did not increase the SOC storage mainly because of the offsetting effects of enhanced RC and decreased LC, whereas no clear SOC increases under the SNPK fertilization resulted from the fast decay rates of soil C.

  3. Long-term fertilization alters chemically-separated soil organic carbon pools: Based on stable C isotope analyses.

    PubMed

    Dou, Xiaolin; He, Ping; Cheng, Xiaoli; Zhou, Wei

    2016-01-01

    Quantification of dynamics of soil organic carbon (SOC) pools under the influence of long-term fertilization is essential for predicting carbon (C) sequestration. We combined soil chemical fractionation with stable C isotope analyses to investigate the C dynamics of the various SOC pools after 25 years of fertilization. Five types of soil samples (0-20, 20-40 cm) including the initial level (CK) and four fertilization treatments (inorganic nitrogen fertilizer, IN; balanced inorganic fertilizer, NPK; inorganic fertilizer plus farmyard manure, MNPK; inorganic fertilizer plus corn straw residue, SNPK) were separated into recalcitrant and labile fractions, and the fractions were analysed for C content, C:N ratios, δ(13)C values, soil C and N recalcitrance indexes (RIC and RIN). Chemical fractionation showed long-term MNPK fertilization strongly increased the SOC storage in both soil layers (0-20 cm = 1492.4 gC m(2) and 20-40 cm = 1770.6 gC m(2)) because of enhanced recalcitrant C (RC) and labile C (LC). The 25 years of inorganic fertilizer treatment did not increase the SOC storage mainly because of the offsetting effects of enhanced RC and decreased LC, whereas no clear SOC increases under the SNPK fertilization resulted from the fast decay rates of soil C.

  4. Long-term fertilization alters chemically-separated soil organic carbon pools: Based on stable C isotope analyses

    NASA Astrophysics Data System (ADS)

    Dou, Xiaolin; He, Ping; Cheng, Xiaoli; Zhou, Wei

    2016-01-01

    Quantification of dynamics of soil organic carbon (SOC) pools under the influence of long-term fertilization is essential for predicting carbon (C) sequestration. We combined soil chemical fractionation with stable C isotope analyses to investigate the C dynamics of the various SOC pools after 25 years of fertilization. Five types of soil samples (0-20, 20-40 cm) including the initial level (CK) and four fertilization treatments (inorganic nitrogen fertilizer, IN; balanced inorganic fertilizer, NPK; inorganic fertilizer plus farmyard manure, MNPK; inorganic fertilizer plus corn straw residue, SNPK) were separated into recalcitrant and labile fractions, and the fractions were analysed for C content, C:N ratios, δ13C values, soil C and N recalcitrance indexes (RIC and RIN). Chemical fractionation showed long-term MNPK fertilization strongly increased the SOC storage in both soil layers (0-20 cm = 1492.4 gC m2 and 20-40 cm = 1770.6 gC m2) because of enhanced recalcitrant C (RC) and labile C (LC). The 25 years of inorganic fertilizer treatment did not increase the SOC storage mainly because of the offsetting effects of enhanced RC and decreased LC, whereas no clear SOC increases under the SNPK fertilization resulted from the fast decay rates of soil C.

  5. Long-term fertilization alters chemically-separated soil organic carbon pools: Based on stable C isotope analyses

    PubMed Central

    Dou, Xiaolin; He, Ping; Cheng, Xiaoli; Zhou, Wei

    2016-01-01

    Quantification of dynamics of soil organic carbon (SOC) pools under the influence of long-term fertilization is essential for predicting carbon (C) sequestration. We combined soil chemical fractionation with stable C isotope analyses to investigate the C dynamics of the various SOC pools after 25 years of fertilization. Five types of soil samples (0–20, 20–40 cm) including the initial level (CK) and four fertilization treatments (inorganic nitrogen fertilizer, IN; balanced inorganic fertilizer, NPK; inorganic fertilizer plus farmyard manure, MNPK; inorganic fertilizer plus corn straw residue, SNPK) were separated into recalcitrant and labile fractions, and the fractions were analysed for C content, C:N ratios, δ13C values, soil C and N recalcitrance indexes (RIC and RIN). Chemical fractionation showed long-term MNPK fertilization strongly increased the SOC storage in both soil layers (0–20 cm = 1492.4 gC m2 and 20–40 cm = 1770.6 gC m2) because of enhanced recalcitrant C (RC) and labile C (LC). The 25 years of inorganic fertilizer treatment did not increase the SOC storage mainly because of the offsetting effects of enhanced RC and decreased LC, whereas no clear SOC increases under the SNPK fertilization resulted from the fast decay rates of soil C. PMID:26750143

  6. 75 FR 17939 - EMD Chemicals, Inc.; Withdrawal of Color Additive Petition

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-08

    ... the Federal Register of September 25, 1998 (63 FR 51359), FDA announced that a color additive petition... published an amended filing notice in the Federal Register of June 21, 1999 (64 FR 33097), indicating that... candies, nutritional supplement tablets and gelatin capsules, and chewing gum (71 FR 31927). The...

  7. Chemical additive to maximize antimicrobial effect of chlorine during pilot scale immersion chilling of broiler carcasses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A prior laboratory scale study demonstrated the potential for T-128, a proprietary blend including propylene glycol and phosphoric acid, to enhance the antimicrobial efficacy of chlorine during immersion chilling of broiler parts. The objective of the current study was to test the addition of T-128...

  8. Does the Addition of Inert Gases at Constant Volume and Temperature Affect Chemical Equilibrium?

    ERIC Educational Resources Information Center

    Paiva, Joao C. M.; Goncalves, Jorge; Fonseca, Susana

    2008-01-01

    In this article we examine three approaches, leading to different conclusions, for answering the question "Does the addition of inert gases at constant volume and temperature modify the state of equilibrium?" In the first approach, the answer is yes as a result of a common students' alternative conception; the second approach, valid only for ideal…

  9. Inorganic chemical analyses of black shale from wells in the National Petroleum Reserve in Alaska

    SciTech Connect

    Brosge, W.P.; Tailleur, I.L.

    1989-01-01

    Core samples of Mississippian through Upper Cretaceous black shale, siltstone, and limy mudstone from 24 test wells in the National Petroleum Reserve in Alaska (NPRA) have been analyzed for trace elements in order to provide data on regional background concentrations for inorganic geochemical exploration. This study was made because the authors had noticed that several of the rock units cored in the subsurface were associated with surface geochemical anomalies or small mineral deposits in the areas where they crop out. In the southwestern part of the NPRA, the heavy-mineral concentrates from sediments of streams that flow over shale and graywacke of the Lower Cretaceous Fortress Mountain and Torok Formations are unusually rich in lead, arsenic, and silver. Southeast of the NPRA, in the foothills of the Philip Smith Mountains, stream sediments in areas of Permian to Lower Cretaceous shale locally contain anomalously large amounts of zinc and thorium. In addition, the high organic-carbon content of the Shublick Formation, Jurassic (part) Kingak Shale, and lowest Cretaceous pebble shale unit in the subsurface in the Prudhoe Bay area indicate that they may be rich in trace metals. Outcrops of the Shublik in the Brooks Range locally contain much copper, molybdenum, vanadium, and rare-earth elements, and the high gamma-radiation characteristic of the pebble shale unit in the subsurface shows that it is rich in uranium and thorium. The shale section with the most important known metallic deposits is the Mississippian shale and chert now assigned to the Kuna Formation. The distribution of vanadium and nickel may also be of interest in oil exploration. Hughes and others found higher V/Ni ratios in the Prudhoe-Barrow types of oil than in the Umiat-Simpson types and attributed these higher ratios to sources in the Shublik Formation and Jurassic (part) Kingak Shale.

  10. Anaerobic digestion of high-strength cheese whey utilizing semicontinuous digesters and chemical flocculant addition

    SciTech Connect

    Barford, J.P.; Cail, R.G.; Callander, I.J.; Floyd, E.J.

    1986-11-01

    Semicontinuous digesters were used to anaerobically treat high-strength whey (70 kg/cubic m COD). A maximum loading of 16.1 kg COD/cubic m/day was obtained with soluble COD removal efficiencies greater than 99%. The use of a chemical flocculant resulted in an increased biomass concentration in the digester compared to a control, thus enabling correspondingly higher space loadings to be applied. With the onset of substantial levels of granulation of the biomass, flocculant dosage was able to be discontinued. This article discusses the performance of the digesters in detail and, briefly, the long-term operational difficulties experienced and the control strategies employed on such systems. 24 references.

  11. Effects of Microbial Additives on Chemical Composition and Fermentation Characteristics of Barley Silage

    PubMed Central

    Amanullah, S. M.; Kim, D. H.; Lee, H. J.; Joo, Y. H.; Kim, S. B.; Kim, S. C.

    2014-01-01

    This study examined the effects of bacterial inoculants on chemical composition and fermentation indices of barley silage. Barley forage (Youngyang) was harvested at 24% dry matter (DM) and wilted to 47.9% DM. The wilted barley forage was chopped to 3–5 cm length and applied with no inoculant (CON), L. plantarum (1×1010 cfu/g, LP) or Effective Microorganisms (0.5×109 cfu/g, EM). Then the forages were ensiled in four replications for each treatment in 20 L mini silos and stored for 100 days. The contents of crude protein and ether extract were higher in CON silage ensiled for 100-d, while the contents of DM and crude ash were higher in EM silage (p<0.05). The contents of ADF, NDF and hemicellulose as well as the in vitro DM digestibility were not affected by microbial inoculation (p>0.05). The pH, ammonia-N concentration and lactate to acetate ratio were higher (p<0.05) in CON silage, while lactate concentrations were higher (p<0.05) in CON and LP silage. Acetate concentration and lactic acid bacteria was increased (p<0.05) by both inoculants (LP and EM), but propionate concentration and yeast was increased (p<0.05) by EM and LP, respectively. These results indicated that the fermentation quality of barley silage was improved by the application of bacterial inoculants. PMID:25049981

  12. Accelerated Stability Studies on Dried Extracts of Centella asiatica Through Chemical, HPLC, HPTLC, and Biological Activity Analyses.

    PubMed

    Kaur, Ishtdeep; Suthar, Nancy; Kaur, Jasmeen; Bansal, Yogita; Bansal, Gulshan

    2016-10-01

    Regulatory guidelines recommend systematic stability studies on a herbal product to establish its shelf life. In the present study, commercial extracts (Types I and II) and freshly prepared extract (Type III) of Centella asiatica were subjected to accelerated stability testing for 6 months. Control and stability samples were evaluated for organoleptics, pH, moisture, total phenolic content (TPC), asiatic acid, kaempherol, and high-performance thin layer chromatography fingerprints, and for antioxidant and acetylcholinesterase inhibitory activities. Markers and TPC and both the activities of each extract decreased in stability samples with respect to control. These losses were maximum in Type I extract and minimum in Type III extract. Higher stability of Type III extract than others might be attributed to the additional phytoconstituents and/or preservatives in it. Pearson correlation analysis of the results suggested that TPC, asiatic acid, and kaempferol can be taken as chemical markers to assess chemical and therapeutic shelf lives of herbal products containing Centella asiatica.

  13. The Effects of Chemical Additives on the Induction Phase in Solid-State Thermal Decomposition of Ammonia Borane

    SciTech Connect

    Heldebrant, David J.; Karkamkar, Abhijeet J.; Hess, Nancy J.; Bowden, Mark E.; Rassat, Scot D.; Zheng, Feng; Rappe, Kenneth G.; Autrey, Thomas

    2008-08-26

    The solid-state decomposition of ammonia borane (AB) alone and in the presence of chemical additives was investigated by a series of experimental methods to develop an approach for reducing the induction period for hydrogen release. Gas chromatography techniques were used to measure the yield of hydrogen as a function of time under isothermal conditions between 70 and 90 °C, and the polyaminoborane (PAB) products produced from hydrogen loss from AB show significant cross linking by 11B NMR spectroscopy. Raman microscopy was used to follow the transformation of crystalline AB to amorphous AB with the subsequent formation of the diammoniate of diborane (DADB). A gas burette was used to monitor the time-dependent release of hydrogen from AB in the presence of chemical additives. The combination of these approaches provides insight into the mechanism of hydrogen release from solid AB. The release of molecular hydrogen is described by a process involving sequential induction (disruption of dihydrogen bonds), nucleation (formation of DADB), and growth (hydrogen release through dehydrocoupling). Addition of DADB or ammonium chloride to neat AB significantly reduces the induction time for hydrogen release. The authors wish to acknowledge support from the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy. This work was performed as part of the Center of Excellence in Chemical Hydrogen Storage and in collaboration with the International Partnership for the Hydrogen Economy. Pacific Northwest National Laboratory is operated for the U.S. Department of Energy by Battelle.

  14. Assessment of chemical analyses by means of portable XRF in the Roman mortars of Complutum archaeological site (Spain)

    NASA Astrophysics Data System (ADS)

    Ergenç, Duygu; Freire, David; Fort, Rafael

    2016-04-01

    The chemical characterization of lime mortars used in Roman period has a great significance and plays a key role in the acquisition of knowledge with respect to construction technology, raw materials and, accordingly, in its conservation works. When it comes to cultural heritage studies, sampling is always complicated since the minimum damage is the primary concern. The use of non-destructive techniques and direct measurements with portable devices reduce the amount of samples and time consumed in analyses, consequently it could be stated that such techniques are extremely useful in conservation and restoration works. In this study, the portable XRF device was used to determine the composition of chemical elements which compose the Roman lime mortars in the archaeological site of Complutum, Alcalá de Henares (Madrid, Spain) which is listed as a World Heritage Site by UNESCO since 1998. Portable XRF devices have some detection limits below the ones of the laboratory equipment that are immovable and require sampling. In order to correlate the results, sampling and grinding were initially done to prepare the powders for the laboratory XRF analysis with the following elements: Si, Al, Fe, Ca, Mg, K, Ti, Nb, Zr, Sr, Rb, Pb, Zn and Cr. The analyses of the powdered samples were conducted with the laboratory equipment PHILIPS Magix Pro (PW-2440) from the Centre of Scientific Instrumentation CIC in the University of Granada, and the results were compared to the results gathered with X Ray Florescence (EDTRX) THERMO NITON model XL3T from the Petrophysics Laboratory Geosciences Institute IGEO (CSIC-UCM). Analyses were performed on the surfaces of the samples -without any previous preparation-, and on the powdered samples to compare the variations between both traditional XRF analyses and the portable XRF. A good correlation was found among the results obtained by the laboratory equipment, the portable device as well as the surface measurements. The results of this study

  15. Chemical analyses of stream sediment in the Tar Creek basin of the Picher mining area, northeast Oklahoma

    USGS Publications Warehouse

    Parkhurst, David L.; Doughten, Michael; Hearn,, Paul P.

    1988-01-01

    Chemical analyses are presented for 47 sediment samples from the Tar Creek drainage in the Picher mining area of northeast Oklahoma. The samples were taken in December 1983, June 1984, and June 1985. All of the samples were taken downstream from mine-water discharge points of abandoned lead and zinc mines. The 34 samples taken in December 1983 and June 1984 were analyzed semiquantitatively by emission spectrography for 64 elements and quantitatively for cadmium, copper, iron, manganese, nickel, lead, sulfur, zinc, and organic carbon. The 13 samples taken in June 1985 were analyzed quantitatively for aluminum, cadmium, cobalt, chromium, copper, iron, manganese, molybdenum, nickel, phosphorus, lead, sulfur, silicon, titanium, vanadium, zinc, and organic carbon.

  16. Monitoring and analyses of substrate surface in first stages of graphene growth in plasma-enhanced chemical vapor deposition

    NASA Astrophysics Data System (ADS)

    Kawano, Masahiro; Yamada, Shunya; Hayashi, Yasuaki

    2016-06-01

    In situ ellipsometry was carried out as well as ex situ measurements by scanning electron microscopy and Raman spectroscopy for the analyses of substrate surface in the first stage of graphene growth in plasma-enhanced chemical vapor deposition. Evolutions of the ellipsometric parameters Ψ and Δ were precisely measured during the growth of graphene with the sensitivity far less than 1 nm in film thickness. By the fitting of the experimentally obtained trajectory of ellipsometric parameters on the Ψ-Δ coordinate plane to that of the calculated ones, we confirmed that the graphite volume fraction decreased with growth after a dense graphite material initially formed. This suggests that carbon nanowalls grew on a thin graphitic layer.

  17. The effect of a chemical additive on the fermentation and aerobic stability of high-moisture corn.

    PubMed

    Da Silva, T C; Smith, M L; Barnard, A M; Kung, L

    2015-12-01

    The objective of this experiment was to evaluate the effect of a chemical additive on the fermentation and aerobic stability of high-moisture corn (HMC). Ground HMC (~63% dry matter) was untreated, or treated with an additive containing sodium benzoate, potassium sorbate, and sodium nitrite as active ingredients, at 0, 2, 3, or 4 L/t of fresh matter. Laboratory silos (7.5 L) were prepared and ensiled for 21 and 90d (4 silos/treatment per d of ensiling). Small bag silos were prepared for untreated HMC and HMC treated with 4 L/t of the additive and analyzed for nitrate-N and nitrite-N after 0, 3, and 7d of ensiling. The concentration of nitrate-N was similar between these 2 treatments and was below levels considered problematic for ruminants. Nitrite-N was greater in HMC treated with the high level of additive but was also very low for both treatments. Numbers of yeasts were similar among treatments in fresh HMC and decreased substantially after ensiling. Numbers of yeasts were similar among treatments after 21d of ensiling but after 90d they were lower in treated versus untreated HMC. Concentrations of organic acids (lactic, acetic, and propionic) and pH were not different among treatments at any time of ensiling. In contrast, treatment with the additive markedly decreased the concentration of ethanol in HMC after 21 and 90d when compared with untreated HMC. Treatment with all levels of the additive markedly improved the aerobic stability and improved the recovery of dry matter compared with untreated HMC. Overall, our findings suggest that the chemical additive used in this study has the potential to improve the fermentation and aerobic stability of HMC after a relatively short period (21d) and after a moderate length (90d) of ensiling. PMID:26454298

  18. A combined approach to investigate the toxicity of an industrial landfill's leachate: Chemical analyses, risk assessment and in vitro assays

    SciTech Connect

    Baderna, D.; Maggioni, S.; Boriani, E.; Gemma, S.; Molteni, M.; Lombardo, A.; Colombo, A.; Bordonali, S.; Rotella, G.; Lodi, M.; Benfenati, E.

    2011-05-15

    Solid wastes constitute an important and emerging problem. Landfills are still one of the most common ways to manage waste disposal. The risk assessment of pollutants from landfills is becoming a major environmental issue in Europe, due to the large number of sites and to the importance of groundwater protection. Furthermore, there is lack of knowledge for the environmental, ecotoxicological and toxicological characteristics of most contaminants contained into landfill leacheates. Understanding leachate composition and creating an integrated strategy for risk assessment are currently needed to correctly face the landfill issues and to make projections on the long-term impacts of a landfill, with particular attention to the estimation of possible adverse effects on human health and ecosystem. In the present study, we propose an integrated strategy to evaluate the toxicity of the leachate using chemical analyses, risk assessment guidelines and in vitro assays using the hepatoma HepG2 cells as a model. The approach was applied on a real case study: an industrial waste landfill in northern Italy for which data on the presence of leachate contaminants are available from the last 11 years. Results from our ecological risk models suggest important toxic effects on freshwater fish and small rodents, mainly due to ammonia and inorganic constituents. Our results from in vitro data show an inhibition of cell proliferation by leachate at low doses and cytotoxic effect at high doses after 48 h of exposure. - Research highlights: {yields} We study the toxicity of leachate from a non-hazardous industrial waste landfill. {yields} We perform chemical analyses, risk assessments and in vitro assays on HepG2 cells. {yields} Risk models suggest toxic effects due to ammonia and inorganic constituents. {yields} In vitro assays show that leachate inhibits cell proliferation at low doses. {yields} Leachate can induce cytotoxic effects on HepG2 cells at high doses.

  19. Effect of addition of Versagel on microbial, chemical, and physical properties of low-fat yogurt.

    PubMed

    Ramchandran, L; Shah, N P

    2008-09-01

    The objective of this study was to examine the effect of Versagel on the growth and proteolytic activity of Streptococcus thermophilus 1275 and Lactobacillus delbrueckii ssp. bulgaricus 1368 and angiotensin-I converting enzyme inhibitory activity of the peptides generated thereby as well as on the physical properties of low-fat yogurt during a storage period of 28 d at 4 degrees C. Three different types of low-fat yogurts, YV0, YV1, and YV2, were prepared using Versagel as a fat replacer. The fermentation time of the low-fat yogurts containing Versagel was less than that of the control yogurt (YV0). The starter cultures maintained their viability (8.68 to 8.81 log CFU/g of S. thermophilus and 8.51 to 8.81 log CFU/g of L. delbrueckii ssp. bulgaricus) in all the yogurts throughout the storage period. There was some decrease in the pH of the yogurts during storage and an increase in the concentration of lactic acid. However, the proteolytic and ACE-inhibitory potential of the starter cultures was suppressed in the presence of Versagel. On the other hand, the addition of Versagel had a positive impact on the physical properties of the low-fat yogurt, namely, spontaneous whey separation, firmness, and pseudoplastic properties.

  20. Chemical and mineralogical analyses of planetary rocks using a laser ablation mass spectrometer for in situ space research

    NASA Astrophysics Data System (ADS)

    Brigitte Neuland, Maike; Mezger, Klaus; Riedo, Andreas; Tulej, Marek; Wurz, Peter

    2015-04-01

    The context chemical analysis is of considerable importance in space research. High resolution in situ studies of planetary materials can yield important information on surface heterogeneity, basic grain mineralogy and chemical composition of surface and subsurface. In turn, these data are the basis for our understanding of the physical and chemical processes which led to the formation and alteration of planetary material [1] [2]. A highly heterogeneous sample of Allende meteorite, representative for extraterrestrial material, is investigated by LMS, a miniature laser ablation mass spectrometer designed for space research [3]. In the current setup a fs-laser ablation ion source is applied, allowing chemical analysis with lateral resolution of about 10-15 μm and sub-micrometre depth resolution [4]. The reflectron TOF mass analyser is used to measure elemental and isotopic composition of the sampled surface. The LMS instrument supports mass resolution 400 and dynamic range of 108 [5]. In the current studies with the fs-ablation ion source significant improvements in the detection efficiency of several metals e.g., Ni, Co, and non-metals e.g., Si, P, S and O, was achieved comparing to our previous setup [6]. Also the values of sensitivity coefficients for these elements are determined to be close to one, which resulted in the substantial improvements of the quantitative element analysis of the sample. Since the ablation crater depth is expected to be about 1 nm/laser shot also the possible changes of the main element or isotope distribution in depth can be analysed to assess their influence on the mineralogical analysis [7]. Several areas on an Allende sample were investigated and the chemical composition across the surface was determined from the mass spectrometric analysis. Also accurate isotope analysis could be conducted for most of main elements with sufficiently high signal to noise ratio. Correlation of elements was conducted and yielded mineralogical maps

  1. Evaluation of toxicity and estrogenicity of the landfill-concentrated leachate during advanced oxidation treatment: chemical analyses and bioanalytical tools.

    PubMed

    Wang, Guifang; Lu, Gang; Zhao, Jiandi; Yin, Pinghe; Zhao, Ling

    2016-08-01

    Landfill-concentrated leachate from membrane separation processes is a potential pollution source for the surroundings. In this study, the toxicity and estrogenicity potentials of concentrated leachate prior to and during UV-Fenton and Fenton treatments were assessed by a combination of chemical (di (2-ethylhexyl) phthalate and dibutyl phthalate were chosen as targets) and biological (Daphnia magna, Chlorella vulgaris, and E-screen assay) analyses. Removal efficiencies of measured di (2-ethylhexyl) phthalate and dibutyl phthalate were more than 97 % after treatment with the two methods. Biological tests showed acute toxicity effects on D. magna tests in untreated concentrated leachate samples, whereas acute toxicity on C. vulgaris tests was not observed. Both treatment methods were found to be efficient in reducing acute toxicity effects on D. magna tests. The E-screen test showed concentrated leachate had significant estrogenicity, UV-Fenton and Fenton treatment, especially the former, were effective methods for reducing estrogenicity of concentrated leachate. The EEQchem (estradiol equivalent concentration) of all samples could only explain 0.218-5.31 % range of the EEQbio. These results showed that UV-Fenton reagent could be considered as a suitable method for treatment of concentrated leachate, and the importance of the application of an integrated (biological + chemical) analytical approach for a comprehensive evaluation of treatment suitability. PMID:27146535

  2. Effects of 8 chemical and bacterial additives on the quality of corn silage.

    PubMed

    Queiroz, O C M; Arriola, K G; Daniel, J L P; Adesogan, A T

    2013-09-01

    This project aimed to evaluate the effects 8 additives on the fermentation, dry matter (DM) losses, nutritive value, and aerobic stability of corn silage. Corn forage harvested at 31% DM was chopped (10mm) and treated with (1) deionized water (control); (2) Buchneri 500 (BUC; 1×10(5) cfu/g of Pediococcus pentosaceus 12455 and 4×10(5) cfu/g of Lactobacillus buchneri 40788; Lallemand Animal Nutrition, Milwaukee, WI); (3) sodium benzoate (BEN; 0.1% of fresh forage); (4) Silage Savor acid mixture (SAV: 0.1% of fresh forage; Kemin Industries Inc., Des Moines, IA); (5) 1×10(6) cfu/g of Acetobacter pasteurianus-ATCC 9323; (6) 1×10(6) cfu/g of Gluconobacter oxydans-ATCC 621; (7) Ecosyl 200T (1×10(5) cfu/g of Lactobacillus plantarum MTD/1; Ecosyl Products Inc., Byron, IL); (8) Silo-King WS (1.5×10(5) cfu/g of L. plantarum, P. pentosaceus and Enterococcus faecium; Agri-King, Fulton, IL); and (9) Biomax 5 (BIO; 1×10(5) cfu/g of L. plantarum PA-28 and K-270; Chr. Hansen Animal Health and Nutrition, Milwaukee, WI). Treated forage was ensiled in quadruplicate in mini silos at a density of 172 kg of DM/m(3) for 3 and 120 d. After 3 d of ensiling, the pH of all silages was below 4 but ethanol concentrations were least in BEN silage (2.03 vs. 3.24% DM) and lactic acid was greatest in SAV silage (2.97 vs. 2.51% DM). Among 120-d silages, additives did not affect DM recovery (mean=89.8% ± 2.27) or in vitro DM digestibility (mean=71.5% ± 0.63). The SAV silage had greater ammonia-N (0.85 g/kg of DM) and butyric acid (0.22 vs. 0.0% DM) than other treatments. In contrast, BEN and Silo-King silages had the least ammonia-N concentration and had no butyric acid. The BEN and A. pasteurianus silages had the lowest pH (3.69) and BEN silage had the least ethanol (1.04% DM) and ammonia nitrogen (0.64 g/kg DM) concentrations, suggesting that fermentation was more extensive and protein degradation was less in BEN silages. The BUC and BIO silages had greater acetic acid concentrations than

  3. Activation and stabilization of the hydroperoxide lyase enzymatic extract from mint leaves (Mentha spicata) using selected chemical additives.

    PubMed

    Akacha, Najla B; Karboune, Salwa; Gargouri, Mohamed; Kermasha, Selim

    2010-03-01

    The effects of selected lyoprotecting excipients and chemical additives on the specific activity and the thermal stability of the hydroperoxide lyase (HPL) enzymatic extract from mint leaves were investigated. The addition of KCl (5%, w/w) and dextran (2.5%, w/w) to the enzymatic extract, prior to lyophilization, increased the HPL specific activity by 2.0- and 1.2-fold, respectively, compared to the control lyophilized extract. From half-life time (t (1/2)), it can be seen that KCl has enhanced the HPL stability by 1.3- to 2.3-fold, during long-period storage at -20 degrees Celsius and 4 degrees Celsius. Among the selected additives used throughout this study, glycine appeared to be the most effective one. In addition to the activation effect conferred by glycine, it also enhanced the HPL thermal stability. In contrast, polyhydroxyl-containing additives were not effective for stabilizing the HPL enzymatic extract. On the other hand, there was no signification increase in HPL activity and its thermal stability with the presence of Triton X-100. The results also showed that in the presence of glycine (10%), the catalytic efficiency of HPL was increased by 2.45-fold than that without additive.

  4. [Effects of different perlite additions on physical and chemical properties of sewage sludge compost and growth of Tagetes patula].

    PubMed

    Hu, Yu-Tong; Shi, Lian-Hui; Liu, Deng-Min; Tong, Shao-Wei; Wei, Mei-Yan; Sun, Jie

    2014-07-01

    In order to resolve the problem of poor permeability of sewage sludge compost (SSC) which was used as the substitution of peat, perlite was used to regulate the permeability of the sewage. The pure SSC was used as control. The proportions of perlite in the mixtures with SSC were 20%, 40%, 60%, 80% and 100% (V/V), respectively. The effects of different perlite ratios on the physical and chemical properties and the growth of Tagetes patula were studied. The bulk density, water holding porosity and water holding porosity to aeration porosity decreased, but the total porosity and aeration porosity increased with the increasing addition of perlite to the SSC. For the chemical properties, the pH increased, and the EC and nutrient contents decreased with the increasing addition of perlite to the SSC. The aboveground biomass and flowers of T. patula were the highest in the 60% perlite treatment, and the lowest in the pure SSC treatment. The root morphology and activity were the best in the 40%, 60% and 80% perlite treatments. Aeration was the strongest factor to impact the maximum root length and average root diameter. Perlite promoted the growth of T. patula mainly through impacting the physical properties of the SSC. The addition of 60% perlite to the SSC could significantly improve the poor aeration and decrease the high salinity greatly in the SSC and regulate the growth of the root and aboveground of T. patula. PMID:25345044

  5. Effect of Microbial and Chemical Combo Additives on Nutritive Value and Fermentation Characteristic of Whole Crop Barley Silage

    PubMed Central

    Kim, Dong Hyeon; Amanullah, Sardar M.; Lee, Hyuk Jun; Joo, Young Ho; Kim, Sam Churl

    2015-01-01

    This study was conducted to assess the effects of microbial and chemical combo additives on nutritive values, fermentation indices and aerobic stability of whole crop barley silage. Barley forage (Youngyang) was harvested at about 30% dry matter (DM) by treatments, chopped to 5 cm length and treated with distilled water only (CON), Lactobacillus plantarum (INO), propionic acid (PRO) or an equal mixture of INO and PRO (MIX). Barley forages were ensiled in 4 replications for 0, 2, 7, and 100 days. On 100 days of ensiling, MIX silage had higher (p<0.05) in vitro DM digestibility than CON silage, but lower (p<0.05) acid detergent fiber concentration. The pH in all treated silages was lower (p<0.05) than CON silage. The MIX silage had higher (p<0.05) lactate concentration and lactate to acetate ratio than in CON, but lower (p<0.05) yeast count. Aerobic stability in CON, PRO, and MIX silages were higher (p<0.05) than in INO silage. It is concluded that microbial and chemical combo additives using L. plantarum and propionic acid could efficiently improve nutritive values of barley silage in terms of increased in vitro DM digestibility compared to other treatments. In addition, all treatments except CON reduced yeast count which is the initiate microorganism of aerobic spoilage. PMID:26323517

  6. [Effects of different perlite additions on physical and chemical properties of sewage sludge compost and growth of Tagetes patula].

    PubMed

    Hu, Yu-Tong; Shi, Lian-Hui; Liu, Deng-Min; Tong, Shao-Wei; Wei, Mei-Yan; Sun, Jie

    2014-07-01

    In order to resolve the problem of poor permeability of sewage sludge compost (SSC) which was used as the substitution of peat, perlite was used to regulate the permeability of the sewage. The pure SSC was used as control. The proportions of perlite in the mixtures with SSC were 20%, 40%, 60%, 80% and 100% (V/V), respectively. The effects of different perlite ratios on the physical and chemical properties and the growth of Tagetes patula were studied. The bulk density, water holding porosity and water holding porosity to aeration porosity decreased, but the total porosity and aeration porosity increased with the increasing addition of perlite to the SSC. For the chemical properties, the pH increased, and the EC and nutrient contents decreased with the increasing addition of perlite to the SSC. The aboveground biomass and flowers of T. patula were the highest in the 60% perlite treatment, and the lowest in the pure SSC treatment. The root morphology and activity were the best in the 40%, 60% and 80% perlite treatments. Aeration was the strongest factor to impact the maximum root length and average root diameter. Perlite promoted the growth of T. patula mainly through impacting the physical properties of the SSC. The addition of 60% perlite to the SSC could significantly improve the poor aeration and decrease the high salinity greatly in the SSC and regulate the growth of the root and aboveground of T. patula.

  7. Effect of water treatment additives on lime softening residual trace chemical composition--implications for disposal and reuse.

    PubMed

    Cheng, Weizhi; Roessler, Justin; Blaisi, Nawaf I; Townsend, Timothy G

    2014-12-01

    Drinking water treatment residues (WTR) offer potential benefits when recycled through land application. The current guidance in Florida, US allows for unrestricted land application of lime softening WTR; alum and ferric WTR require additional evaluation of total and leachable concentrations of select trace metals prior to land application. In some cases a mixed WTR is produced when lime softening is accompanied by the addition of a coagulant or other treatment chemical; applicability of the current guidance is unclear. The objective of this research was to characterize the total and leachable chemical content of WTR from Florida facilities that utilize multiple treatment chemicals. Lime and mixed lime WTR samples were collected from 18 water treatment facilities in Florida. Total and leachable concentrations of the WTR were measured. To assess the potential for disposal of mixed WTR as clean fill below the water table, leaching tests were conducted at multiple liquid to solid ratios and under reducing conditions. The results were compared to risk-based soil and groundwater contamination thresholds. Total metal concentrations of WTR were found to be below Florida soil contaminant thresholds with Fe found in the highest abundance at a concentration of 3600 mg/kg-dry. Aluminum was the only element that exceeded the Florida groundwater contaminant thresholds using SPLP (95% UCL = 0.23 mg/L; risk threshold = 0.2 mg/L). Tests under reducing conditions showed elevated concentrations of Fe and Mn, ranging from 1 to 3 orders of magnitude higher than SPLP leachates. Mixed lime WTR concentrations (total and leachable) were lower than the ferric and alum WTR concentrations, supporting that mixed WTR are appropriately represented as lime WTR. Testing of WTR under reducing conditions demonstrated the potential for release of certain trace metals (Fe, Al, Mn) above applicable regulatory thresholds; additional evaluation is needed to assess management options where

  8. Effects of chemical mechanical planarization slurry additives on the agglomeration of alumina nanoparticles II: aggregation rate analysis.

    PubMed

    Brahma, Neil; Talbot, Jan B

    2014-04-01

    The aggregation rate and mechanism of 150 nm alumina particles in 1mM KNO3 with various additives used in chemical mechanical planarization of copper were investigated. The pH of each suspension was ∼8 such that the aggregation rate was slow enough to be measured and analyzed over ∼120 min. In general, an initial exponential growth was observed for most suspensions indicating reaction-limited aggregation. After aggregate sizes increase to >500 nm, the rate followed a power law suggesting diffusion-limited aggregation. Stability ratios and fractal dimension numbers were also calculated to further elucidate the aggregation mechanism. PMID:24491325

  9. Suggested protocol for collecting, handling and preparing peat cores and peat samples for physical, chemical, mineralogical and isotopic analyses.

    PubMed

    Givelet, Nicolas; Le Roux, Gaël; Cheburkin, Andriy; Chen, Bin; Frank, Jutta; Goodsite, Michael E; Kempter, Heike; Krachler, Michael; Noernberg, Tommy; Rausch, Nicole; Rheinberger, Stefan; Roos-Barraclough, Fiona; Sapkota, Atindra; Scholz, Christian; Shotyk, William

    2004-05-01

    For detailed reconstructions of atmospheric metal deposition using peat cores from bogs, a comprehensive protocol for working with peat cores is proposed. The first step is to locate and determine suitable sampling sites in accordance with the principal goal of the study, the period of time of interest and the precision required. Using the state of the art procedures and field equipment, peat cores are collected in such a way as to provide high quality records for paleoenvironmental study. Pertinent field observations gathered during the fieldwork are recorded in a field report. Cores are kept frozen at -18 degree C until they can be prepared in the laboratory. Frozen peat cores are precisely cut into 1 cm slices using a stainless steel band saw with stainless steel blades. The outside edges of each slice are removed using a titanium knife to avoid any possible contamination which might have occurred during the sampling and handling stage. Each slice is split, with one-half kept frozen for future studies (archived), and the other half further subdivided for physical, chemical, and mineralogical analyses. Physical parameters such as ash and water contents, the bulk density and the degree of decomposition of the peat are determined using established methods. A subsample is dried overnight at 105 degree C in a drying oven and milled in a centrifugal mill with titanium sieve. Prior to any expensive and time consuming chemical procedures and analyses, the resulting powdered samples, after manual homogenisation, are measured for more than twenty-two major and trace elements using non-destructive X-Ray fluorescence (XRF) methods. This approach provides lots of valuable geochemical data which documents the natural geochemical processes which occur in the peat profiles and their possible effect on the trace metal profiles. The development, evaluation and use of peat cores from bogs as archives of high-resolution records of atmospheric deposition of mineral dust and trace

  10. Suggested protocol for collecting, handling and preparing peat cores and peat samples for physical, chemical, mineralogical and isotopic analyses.

    PubMed

    Givelet, Nicolas; Le Roux, Gaël; Cheburkin, Andriy; Chen, Bin; Frank, Jutta; Goodsite, Michael E; Kempter, Heike; Krachler, Michael; Noernberg, Tommy; Rausch, Nicole; Rheinberger, Stefan; Roos-Barraclough, Fiona; Sapkota, Atindra; Scholz, Christian; Shotyk, William

    2004-05-01

    For detailed reconstructions of atmospheric metal deposition using peat cores from bogs, a comprehensive protocol for working with peat cores is proposed. The first step is to locate and determine suitable sampling sites in accordance with the principal goal of the study, the period of time of interest and the precision required. Using the state of the art procedures and field equipment, peat cores are collected in such a way as to provide high quality records for paleoenvironmental study. Pertinent field observations gathered during the fieldwork are recorded in a field report. Cores are kept frozen at -18 degree C until they can be prepared in the laboratory. Frozen peat cores are precisely cut into 1 cm slices using a stainless steel band saw with stainless steel blades. The outside edges of each slice are removed using a titanium knife to avoid any possible contamination which might have occurred during the sampling and handling stage. Each slice is split, with one-half kept frozen for future studies (archived), and the other half further subdivided for physical, chemical, and mineralogical analyses. Physical parameters such as ash and water contents, the bulk density and the degree of decomposition of the peat are determined using established methods. A subsample is dried overnight at 105 degree C in a drying oven and milled in a centrifugal mill with titanium sieve. Prior to any expensive and time consuming chemical procedures and analyses, the resulting powdered samples, after manual homogenisation, are measured for more than twenty-two major and trace elements using non-destructive X-Ray fluorescence (XRF) methods. This approach provides lots of valuable geochemical data which documents the natural geochemical processes which occur in the peat profiles and their possible effect on the trace metal profiles. The development, evaluation and use of peat cores from bogs as archives of high-resolution records of atmospheric deposition of mineral dust and trace

  11. Sustainable nutrients recovery and recycling by optimizing the chemical addition sequence for struvite precipitation from raw swine slurries.

    PubMed

    Taddeo, Raffaele; Kolppo, Kari; Lepistö, Raghida

    2016-09-15

    Livestock farming contributes heavily to nitrogen (N) and phosphorus (P) flows into the environment, a major cause of eutrophication of coastal and freshwater systems. Furthermore, the growing demand for N-P fertilizers is increasing the emission of anthropogenic reactive N into the atmosphere and the depletion of the current P reserves. Therefore, it is essential to minimize the anthropogenic impact on the environment and recycle the wasted N-P for agricultural reuse. This study focused on enhancing struvite (MgNH4PO4*6H2O) precipitation from raw swine slurries in batch and laboratory-scale reactors. Different chemical addition sequences were evaluated, and the best removal efficiency (E%) was obtained when the chemicals were mixed before the precipitation process. Struvite was detected at a pH as low as 6 (E%N-P∼50%), and high E%N-P was found at pH 7-9.5 (80-95%). Furthermore, air stripping was used in place of NaOH to adjust pH, returning the same efficiency as if only alkali had been used. XRD and FE-SEM analysis of the precipitate showed that the recovered struvite was of high purity with orthorhombic crystalline structure and only trace amounts of impurities from matrix organics, co-precipitation products (CaO and amorphous calcium-phosphates), and residuals of added chemicals (MgO). PMID:27208994

  12. Sustainable nutrients recovery and recycling by optimizing the chemical addition sequence for struvite precipitation from raw swine slurries.

    PubMed

    Taddeo, Raffaele; Kolppo, Kari; Lepistö, Raghida

    2016-09-15

    Livestock farming contributes heavily to nitrogen (N) and phosphorus (P) flows into the environment, a major cause of eutrophication of coastal and freshwater systems. Furthermore, the growing demand for N-P fertilizers is increasing the emission of anthropogenic reactive N into the atmosphere and the depletion of the current P reserves. Therefore, it is essential to minimize the anthropogenic impact on the environment and recycle the wasted N-P for agricultural reuse. This study focused on enhancing struvite (MgNH4PO4*6H2O) precipitation from raw swine slurries in batch and laboratory-scale reactors. Different chemical addition sequences were evaluated, and the best removal efficiency (E%) was obtained when the chemicals were mixed before the precipitation process. Struvite was detected at a pH as low as 6 (E%N-P∼50%), and high E%N-P was found at pH 7-9.5 (80-95%). Furthermore, air stripping was used in place of NaOH to adjust pH, returning the same efficiency as if only alkali had been used. XRD and FE-SEM analysis of the precipitate showed that the recovered struvite was of high purity with orthorhombic crystalline structure and only trace amounts of impurities from matrix organics, co-precipitation products (CaO and amorphous calcium-phosphates), and residuals of added chemicals (MgO).

  13. Chemical and particle-size evidence for addition of fine dust to soils of the midwestern United States

    NASA Astrophysics Data System (ADS)

    Mason, Joseph A.; Jacobs, Peter M.

    1998-12-01

    Significant long-term atmospheric dust additions to soils are well documented in many parts of the world, but not in the midwestern United States. We investigated elemental mass fluxes associated with soil development in late Wisconsinan loess in Illinois and Minnesota, using Zr as a stable index element. Positive mass fluxes of Al, Fe, and Ti can most plausibly be explained by additions to these soils of fine far-traveled dust, with higher Al/Zr, Fe/Zr, and Ti/Zr ratios than the coarser locally derived loess. High-resolution particle-size analyses support this explanation. The proposed dust influx will complicate efforts to quantify weathering processes in these soils. Far-traveled dust influx could have occurred simultaneously with the final phase of local loess deposition, and/or later, in the Holocene. Depending on the timing of dust influx, many other soils of the region may have been affected by it.

  14. Chemical analyses of soil samples collected from the Sandia National Laboratories/NM, Tonopah Test Range environs, 1994-2005.

    SciTech Connect

    Deola, Regina Anne; Oldewage, Hans D.; Herrera, Heidi M.; Miller, Mark Laverne

    2006-05-01

    From 1994 through 2005, the Environmental Management Department of Sandia National Laboratories (SNL) at the Tonopah Test Range (TTR), NV, has collected soil samples at numerous locations on-site, on the perimeter, and off-site for the purpose of determining potential impacts to the environs from operations at TTR. These samples were submitted to an analytical laboratory of metal-in-soil analyses. Intercomparisons of these results were then made to determine if there was any statistical difference between on-site, perimeter, and off-site samples, or if there were increasing or decreasing trends which indicated that further investigation may be warranted. This work provided the SNL Environmental Management Department with a sound baseline data reference against which to compare future operational impacts. In addition, it demonstrates the commitment that the Laboratories have to go beyond mere compliance to achieve excellence in its operations. This data is presented in graphical format with narrative commentaries on particular items of interest.

  15. Direct Dating and Physico-Chemical Analyses Cast Doubts on the Coexistence of Humans and Dwarf Hippos in Cyprus

    PubMed Central

    Zazzo, Antoine; Lebon, Matthieu; Quiles, Anita; Reiche, Ina; Vigne, Jean-Denis

    2015-01-01

    In the Mediterranean, the island dwarf megafaunas became extinct around the end of the Pleistocene, during a period of rapid and global climate change. In Cyprus, this coincided with the first human presence on the island, as attested by the rock shelter of Akrotiri-Aetokremnos where an Epipaleolithic anthropogenic layer (stratum 2) was found overlying a massive accumulation of pygmy hippopotamus (Phanourios minor (Desmarest, 1822)) [Boekschoten and Sondaar, 1972] bones (stratum 4). The relationship between the two layers is highly controversial and the role played by humans in hippo extinction remains fiercely debated. Here, we provide new, direct radiocarbon and physico-chemical analyses on calcined bones which elucidates the complex depositional history of the assemblage. Bone turquoise was identified using micro-PIXE analysis and depth-profiling together with Vis spectroscopy, demonstrating that these bones were not freshly burned. Bayesian modeling of the radiocarbon dates indicates that stratum 4 accumulated during the first half of the 13th mill cal BP and that calcination occurred several hundred years later. We conclude that accumulation occurred naturally during the beginning of the Younger Dryas and that Epipalaeolithic visitors subsequently used the bones as fuel, starting from the mid-13th mill cal BP. At that time, dwarf hippos were probably already extinct or at least highly endangered. Our results shed new light on the possible causes of hippo extinction, on the subsequent introduction of the wild boar and on the earliest occupation of the island by humans. PMID:26284623

  16. Direct Dating and Physico-Chemical Analyses Cast Doubts on the Coexistence of Humans and Dwarf Hippos in Cyprus.

    PubMed

    Zazzo, Antoine; Lebon, Matthieu; Quiles, Anita; Reiche, Ina; Vigne, Jean-Denis

    2015-01-01

    In the Mediterranean, the island dwarf megafaunas became extinct around the end of the Pleistocene, during a period of rapid and global climate change. In Cyprus, this coincided with the first human presence on the island, as attested by the rock shelter of Akrotiri-Aetokremnos where an Epipaleolithic anthropogenic layer (stratum 2) was found overlying a massive accumulation of pygmy hippopotamus (Phanourios minor (Desmarest, 1822)) [Boekschoten and Sondaar, 1972] bones (stratum 4). The relationship between the two layers is highly controversial and the role played by humans in hippo extinction remains fiercely debated. Here, we provide new, direct radiocarbon and physico-chemical analyses on calcined bones which elucidates the complex depositional history of the assemblage. Bone turquoise was identified using micro-PIXE analysis and depth-profiling together with Vis spectroscopy, demonstrating that these bones were not freshly burned. Bayesian modeling of the radiocarbon dates indicates that stratum 4 accumulated during the first half of the 13th mill cal BP and that calcination occurred several hundred years later. We conclude that accumulation occurred naturally during the beginning of the Younger Dryas and that Epipalaeolithic visitors subsequently used the bones as fuel, starting from the mid-13th mill cal BP. At that time, dwarf hippos were probably already extinct or at least highly endangered. Our results shed new light on the possible causes of hippo extinction, on the subsequent introduction of the wild boar and on the earliest occupation of the island by humans. PMID:26284623

  17. Direct Dating and Physico-Chemical Analyses Cast Doubts on the Coexistence of Humans and Dwarf Hippos in Cyprus.

    PubMed

    Zazzo, Antoine; Lebon, Matthieu; Quiles, Anita; Reiche, Ina; Vigne, Jean-Denis

    2015-01-01

    In the Mediterranean, the island dwarf megafaunas became extinct around the end of the Pleistocene, during a period of rapid and global climate change. In Cyprus, this coincided with the first human presence on the island, as attested by the rock shelter of Akrotiri-Aetokremnos where an Epipaleolithic anthropogenic layer (stratum 2) was found overlying a massive accumulation of pygmy hippopotamus (Phanourios minor (Desmarest, 1822)) [Boekschoten and Sondaar, 1972] bones (stratum 4). The relationship between the two layers is highly controversial and the role played by humans in hippo extinction remains fiercely debated. Here, we provide new, direct radiocarbon and physico-chemical analyses on calcined bones which elucidates the complex depositional history of the assemblage. Bone turquoise was identified using micro-PIXE analysis and depth-profiling together with Vis spectroscopy, demonstrating that these bones were not freshly burned. Bayesian modeling of the radiocarbon dates indicates that stratum 4 accumulated during the first half of the 13th mill cal BP and that calcination occurred several hundred years later. We conclude that accumulation occurred naturally during the beginning of the Younger Dryas and that Epipalaeolithic visitors subsequently used the bones as fuel, starting from the mid-13th mill cal BP. At that time, dwarf hippos were probably already extinct or at least highly endangered. Our results shed new light on the possible causes of hippo extinction, on the subsequent introduction of the wild boar and on the earliest occupation of the island by humans.

  18. Chemical decomposition of 5-aza-2'-deoxycytidine (Decitabine): kinetic analyses and identification of products by NMR, HPLC, and mass spectrometry.

    PubMed

    Rogstad, Daniel K; Herring, Jason L; Theruvathu, Jacob A; Burdzy, Artur; Perry, Christopher C; Neidigh, Jonathan W; Sowers, Lawrence C

    2009-06-01

    The nucleoside analogue 5-aza-2'-deoxycytidine (Decitabine, DAC) is one of several drugs in clinical use that inhibit DNA methyltransferases, leading to a decrease of 5-methylcytosine in newly replicated DNA and subsequent transcriptional activation of genes silenced by cytosine methylation. In addition to methyltransferase inhibition, DAC has demonstrated toxicity and potential mutagenicity, and can induce a DNA-repair response. The mechanisms accounting for these events are not well understood. DAC is chemically unstable in aqueous solutions, but there is little consensus between previous reports as to its half-life and corresponding products of decomposition at physiological temperature and pH, potentially confounding studies on its mechanism of action and long-term use in humans. Here, we have employed a battery of analytical methods to estimate kinetic rates and to characterize DAC decomposition products under conditions of physiological temperature and pH. Our results indicate that DAC decomposes into a plethora of products, formed by hydrolytic opening and deformylation of the triazine ring, in addition to anomerization and possibly other changes in the sugar ring structure. We also discuss the advantages and problems associated with each analytical method used. The results reported here will facilitate ongoing studies and clinical trials aimed at understanding the mechanisms of action, toxicity, and possible mutagenicity of DAC and related analogues.

  19. The effect of chemical additives on the synthesis of ethanol. Technical progress report 15, March 15, 1991--June 15, 1991

    SciTech Connect

    Chuang, S.S.C.; Pien, S.I.

    1991-06-01

    The objective of this research is to elucidate the role of various chemical additives on ethanol synthesis over Rh- and Ni-based catalysts. Chemical additives used for this study will include S, P, Ag, Cu, Mn, and Na which have different electronegativeities. The effect of additives on the surface state of the catalysts, heat of adsorption of reactant molecules, reaction intermediates, reaction pathways, reaction kinetics, and product distributions is/will be investigated by a series of experimental studies of NO adsorption, reactive probing, steady state rate measurement, and transient kinetic study. CO insertion is known to be a key step to the formation of acetaldehyde and ethanol from CO hydrogenation. Reaction of ethylene with syngas is used as a probe to determine CO insertion capabilities of metal catalysts. During the sixth quarter of the project, the mechanism of CO insertion on Ni/SiO{sub 2} was investigated by in-situ infrared spectroscopy. Ni/SiO{sub 2}, a methanation catalyst, has been shown to exhibit CO insertion activity. In situ infrared studies of CO/H{sub 2} and C{sub 2}H{sub 4}/CO/H{sub 2} reactions show that the carbonylation of Ni/SiO{sub 2} to Ni(CO){sub 4} leads to an inhibition of methanation in CO hydrogenation but an enhancement of formation of propionaldehyde in C{sub 2}H{sub 4}/CO/H{sub 2} reaction. The results suggest that the sites for propionaldehyde formation is different from those for methanation.

  20. Optimizing use of the structural chemical analyser (variable pressure FESEM-EDX Raman spectroscopy) on micro-size complex historical paintings characterization.

    PubMed

    Guerra, I; Cardell, C

    2015-10-01

    The novel Structural Chemical Analyser (hyphenated Raman spectroscopy and scanning electron microscopy equipped with an X-ray detector) is gaining popularity since it allows 3-D morphological studies and elemental, molecular, structural and electronic analyses of a single complex micro-sized sample without transfer between instruments. However, its full potential remains unexploited in painting heritage where simultaneous identification of inorganic and organic materials in paintings is critically yet unresolved. Despite benefits and drawbacks shown in literature, new challenges have to be faced analysing multifaceted paint specimens. SEM-Structural Chemical Analyser systems differ since they are fabricated ad hoc by request. As configuration influences the procedure to optimize analyses, likewise analytical protocols have to be designed ad hoc. This paper deals with the optimization of the analytical procedure of a Variable Pressure Field Emission scanning electron microscopy equipped with an X-ray detector Raman spectroscopy system to analyse historical paint samples. We address essential parameters, technical challenges and limitations raised from analysing paint stratigraphies, archaeological samples and loose pigments. We show that accurate data interpretation requires comprehensive knowledge of factors affecting Raman spectra. We tackled: (i) the in-FESEM-Raman spectroscopy analytical sequence, (ii) correlations between FESEM and Structural Chemical Analyser/laser analytical position, (iii) Raman signal intensity under different VP-FESEM vacuum modes, (iv) carbon deposition on samples under FESEM low-vacuum mode, (v) crystal nature and morphology, (vi) depth of focus and (vii) surface-enhanced Raman scattering effect. We recommend careful planning of analysis strategies prior to research which, although time consuming, guarantees reliable results. The ultimate goal of this paper is to help to guide future users of a FESEM-Structural Chemical Analyser system

  1. Detection and characterisation of frauds in bovine meat in natura by non-meat ingredient additions using data fusion of chemical parameters and ATR-FTIR spectroscopy.

    PubMed

    Nunes, Karen M; Andrade, Marcus Vinícius O; Santos Filho, Antônio M P; Lasmar, Marcelo C; Sena, Marcelo M

    2016-08-15

    Concerns about meat authenticity are increasing recently, due to great fraud scandals. This paper analysed real samples (43 adulterated and 12 controls) originated from criminal networks dismantled by the Brazilian Police. This fraud consisted of injecting solutions of non-meat ingredients (NaCl, phosphates, carrageenan, maltodextrin) in bovine meat, aiming to increase its water holding capacity. Five physico-chemical variables were determined, protein, ash, chloride, sodium, phosphate. Additionally, infrared spectra were recorded. Supervised classification PLS-DA models were built with each data set individually, but the best model was obtained with data fusion, correctly detecting 91% of the adulterated samples. From this model, a variable selection based on the highest VIPscores was performed and a new data fusion model was built with only one chemical variable, providing slightly lower predictions, but a good cost/performance ratio. Finally, some of the selected infrared bands were specifically associated to the presence of adulterants NaCl, tripolyphosphate and carrageenan. PMID:27006208

  2. An Ice Core Melter System for Continuous Major and Trace Chemical Analyses of a New Mt. Logan Summit Ice Core

    NASA Astrophysics Data System (ADS)

    Osterberg, E. C.; Handley, M. J.; Sneed, S. D.; Mayewski, P. A.; Kreutz, K. J.; Fisher, D. A.

    2004-12-01

    The ice core melter system at the University of Maine Climate Change Institute has been recently modified and updated to allow high-resolution (<1-2 cm ice/sample), continuous and coregistered sampling of ice cores, most notably the 2001 Mt. Logan summit ice core (187 m to bedrock), for analyses of 34 trace elements (Sr, Cd, Sb, Cs, Ba, Pb, Bi, U, As, Al, S, Ca, Ti, V, Cr, Mn, Fe, Co, Cu, Zn, REE suite) by inductively coupled plasma mass spectrometry (ICP-MS), 8 major ions (Na+, Ca2+, Mg2+, K+, Cl-, SO42-, NO3-, MSA) by ion chromatography (IC), stable water isotopes (δ 18O, δ D, d) and volcanic tephra. The UMaine continuous melter (UMCoM) system is housed in a dedicated clean room with HEPA filtered air. Standard clean room procedures are employed during melting. A Wagenbach-style continuous melter system has been modified to include a pure Nickel melthead that can be easily dismantled for thorough cleaning. The system allows melting of both ice and firn without wicking of the meltwater into unmelted core. Contrary to ice core melter systems in which the meltwater is directly channeled to online instruments for continuous flow analyses, the UMCoM system collects discrete samples for each chemical analysis under ultraclean conditions. Meltwater from the pristine innermost section of the ice core is split between one fraction collector that accumulates ICP-MS samples in acid pre-cleaned polypropylene vials under a class-100 HEPA clean bench, and a second fraction collector that accumulates IC samples. A third fraction collector accumulates isotope and tephra samples from the potentially contaminated outer portion of the core. This method is advantageous because an archive of each sample remains for subsequent analyses (including trace element isotope ratios), and ICP-MS analytes are scanned for longer intervals and in replicate. Method detection limits, calculated from de-ionized water blanks passed through the entire UMCoM system, are below 10% of average Mt

  3. Coupled Metagenomic and Chemical Analyses of Degrading Fungal Necromass and Implications for Microbial Contributions to Stable Soil OC

    NASA Astrophysics Data System (ADS)

    Schreiner, K. M.; Morgan, B. S. T.; Schultz, J.; Blair, N. E.; Egerton-Warburton, L. M.

    2014-12-01

    Fungi comprise a significant portion of total soil biomass, the turnover of which must represent a dominant flux within the soil carbon cycle. Fungal OC can turn over on time scales of days to months, but this process is poorly understood. Here, we examined temporal changes in the chemical and microbial community composition of fungal necromass during a 2 month decomposition experiment in which Fusarium avenaceum (a common saprophyte) was exposed to a natural soil microbial community. Over the course of the experiment, residual fungal necromass was harvested and analyzed using FTIR and thermochemolysis-GCMS to examine chemical changes in the tissue. Additionally, genomic DNA was extracted from tissues, amplified with barcoded ITS primers, and sequenced using the high-throughput Illumina platform to examine changes in microbial community composition. Up to 80% of the fungal necromass turned over in the first week. This rapid degradation phase corresponded to colonization of the necromass by known chitinolytic soil fungi including Mortierella species. Zygomycetes and Ascomycetes were among the dominant fungal species involved in degradation with very small contributions from Basidiomycetes. At the end of the 2 month degradation, only 15% of the original necromass remained. The residual material was rich in amide and C-O moieties which is consistent with previous work predicting that peptidoglycans are the main residual product from microbial tissue degradation. Straight-chain fatty acids exhibit varying degradation profiles, with some fatty acids (e.g. C16 and C18:1) degrading more rapidly than bulk tissue, others maintaining steady concentrations relative to bulk OC (e.g. C18), and some increasing in concentration throughout the degradation (e.g. C24). These results indicate that the turnover of fungal necromass has the potential to significantly influence a variety of soil OC properties, including C/N ratios, lipid biomarker distributions, and OC turnover times.

  4. Integrated light chemical tagging analyses of seven M31 outer halo globular clusters from the Pan-Andromeda Archaeological Survey

    NASA Astrophysics Data System (ADS)

    Sakari, Charli M.; Venn, Kim A.; Mackey, Dougal; Shetrone, Matthew D.; Dotter, Aaron; Ferguson, Annette M. N.; Huxor, Avon

    2015-04-01

    Detailed chemical abundances are presented for seven M31 outer halo globular clusters (with projected distances from M31 greater than 30 kpc), as derived from high-resolution integrated light spectra taken with the Hobby-Eberly Telescope. Five of these clusters were recently discovered in the Pan-Andromeda Archaeological Survey (PAndAS) - this paper presents the first determinations of integrated Fe, Na, Mg, Ca, Ti, Ni, Ba, and Eu abundances for these clusters. Four of the target clusters (PA06, PA53, PA54, and PA56) are metal poor ([Fe/H] < -1.5), α-enhanced (though they are possibly less α-enhanced than Milky Way stars at the 1σ level), and show signs of star-to-star Na and Mg variations. The other three globular clusters (H10, H23, and PA17) are more metal rich, with metallicities ranging from [Fe/H] = -1.4 to -0.9. While H23 is chemically similar to Milky Way field stars, Milky Way globular clusters, and other M31 clusters, H10 and PA17, have moderately low [Ca/Fe], compared to Milky Way field stars and clusters. Additionally, PA17's high [Mg/Ca] and [Ba/Eu] ratios are distinct from Milky Way stars, and are in better agreement with the stars and clusters in the Large Magellanic Cloud. None of the clusters studied here can be conclusively linked to any of the identified streams from PAndAS; however, based on their locations, kinematics, metallicities, and detailed abundances, the most metal-rich PAndAS clusters H23 and PA17 may be associated with the progenitor of the Giant Stellar Stream, H10 may be associated with the SW cloud, and PA53 and PA56 may be associated with the eastern cloud.

  5. Chemical characteristics of beddings for swine: effects of bedding depths and of addition of inoculums in a pilot-scale.

    PubMed

    Corrêa, E K; Corezzolla, J L; Corrêa, M N; Bianchi, I; Gil-Turnes, C; Lucia, T

    2012-11-01

    The effect of depths and of addition of inoculums on the chemical content of swine beddings was evaluated. For beddings 0.25m (25D) and 0.50m (50D) deep, three treatments were tested in two repeats with the same beddings: control (no inoculums); T1 (250g of Bacillus cereus var. toyoii at 8.4×10(7)CFU/g); and T2 (250g of a pool of Bacillus sp. at 8.4×10(7)CFU/g) (250g for 25D and 500g for 50D). For 25D, the C:N ratio was lower, but N, K and C contents were greater than for 50D (P<0.05). The inoculums did not benefit any chemical parameter (P>0.05). In the second repeat, beddings presented lower C:N ratio and greater N, P and K contents than in the first repeat (P<0.05). Thus, the compost produced after using 25D twice had greater fertilizer value than that of 50D.

  6. Characteristics of concentration-inhibition curves of individual chemicals and applicability of the concentration addition model for mixture toxicity prediction.

    PubMed

    Wang, Na; Wang, Xiaochang C; Ma, Xiaoyan

    2015-03-01

    The concentration addition (CA) model has been widely applied to predict mixture toxicity. However, its applicability is difficult to evaluate due to the complexity of interactions among substances. Considering that the concentration-response curve (CRC) of each component of the mixture is closely related to the prediction of mixture toxicity, mathematical treatments were used to derive a characteristic index kECx (k was the slope of the tangent line of a CRC at concentration ECx). The implication is that the CA model would be applicable for predicting the mixture toxicity only when chemical components have similar kECx in the whole or part of the concentration range. For five selected chemicals whose toxicity was detected using luminescent bacteria, sodium dodecyl benzene sulfonate (SDBS) showed much higher kECx values than the others and its existence in the binary mixtures brought about overestimation of the mixture toxicity with the CA model. The higher the mass ratio of SDBS in a multi-mixture was, the more the toxicity prediction deviated from measurements. By applying the method proposed in this study to analyze some published data, it is confirmed that some components having significantly different kECx values from the other components could explain the large deviation of the mixture toxicity predicted by the CA model. PMID:25499050

  7. Chemical analyses of ground water for saline-water resources studies in Texas Coastal Plain stored in National Water Data Storage and Retrieval System

    USGS Publications Warehouse

    Taylor, R.E.

    1975-01-01

    Chemical analyses of 4,269 water samples from wells in 66 counties in Texas have been processed into the National Water Data Storage and Retrieval System by the Gulf Coast Hydrogeology Project of the U. S. Geological Survey. More than 65,000 chemical analyses of saline waters produced by oil test and production wells have been contributed to the project by major oil companies. The computerized tabulation and the computer-drawn map of the locations of sampling sites are the initial release of oil company, State, and Federal data in Texas Coastal Plain from the data bank.

  8. Records of wells, drillers' logs, water-level measurements, and chemical analyses of ground water in Brazoria, Fort Bend, and Waller counties, Texas, 1985-89

    USGS Publications Warehouse

    Locke, Glenn L.

    1991-01-01

    Data for water wells and ground water in Brazoria, Fort Bend, and Waller Counties were collected during 1985-89 by the U.S. Geological Survey. This report presents a compilation of records for 32 wells in Brazoria County, 19 wells in Fort Bend County, and 16 wells in Waller County. Drillers' logs for 65 wells, water levels for 85 wells, chemical analyses of water for 9 wells, and water levels and chemical analyses of water from previously inventoried wells also are presented in this report.

  9. Records of wells, drillers' logs, water-level measurements, and chemical analyses of ground water in Chambers, Liberty, and Montgomery counties, Texas, 1985-89

    USGS Publications Warehouse

    Locke, Glenn L.

    1991-01-01

    Data for water wells and ground water in Chambers, Liberty, and Montgomery Counties were collected during 1985-89 by the U.S. Geological Survey. This report presents a compilation of records for 4 wells in Chambers County, 8 wells in Liberty County, and 64 wells in Montgomery County. Drillers' logs of 60 wells, water levels for 84 wells, chemical analyses of water for 11 wells, and water levels and chemical analyses of water from previously inventoried wells also are presented in this report.

  10. Nutrient intake and health status of lactovegetarians: chemical analyses of diets using the duplicate portion sampling technique.

    PubMed

    Abdulla, M; Aly, K O; Andersson, I; Asp, N G; Birkhed, D; Denker, I; Johansson, C G; Jägerstad, M; Kolar, K; Nair, B M

    1984-08-01

    Six middle-aged lactovegetarians (three men and three women) collected copies of four 24-h diets using the duplicate portion sampling technique. By chemical analyses, the nutrient composition of the lactovegetarian diet was determined in detail and compared with that of a mixed Swedish diet (normal) and a vegan diet (vegan) studied previously. The nutrient composition of the lactovegetarian diet expressed per 1000 kcal represented an average between normal and vegan diets. It was in closer agreement with Swedish recommended dietary allowances than the normal Swedish diet. Thus, the lactovegetarian diet contained 35% of the energy as fat and was rich in polyunsaturated fatty acids, especially linoleic acid, which resulted in a polyunsaturated/saturated fat ratio of 0.6. The lactovegetarian diet had a cholesterol concentration only half of that of a normal diet. Protein content and amino acid composition were well above recommendations. The lactovegetarian diets contained less sucrose than normal and vegan diets, but the sum of the intake of low molecular weight carbohydrates was comparable to normal and vegan diets. Dietary fiber was three times higher than in a normal diet. Essential minerals and trace elements, ie, Ca, Mg, Na, K, Fe, Zn, Cu, Se, satisfied current requirements. The intake of vitamin B12 by the lactovegetarians was around 1.4 micrograms daily, which is below the recommendations. The intake of folates was high, 300 to 400 micrograms daily. The clinical and biochemical investigation of the subjects revealed no signs of nutritional deficiency. Their plasma lipoproteins and the blood pressures were low for their age, in agreement with observations made earlier in a group of vegans.

  11. Additive effects on the androgen signaling pathway by chemicals with different modes of action-COW2015

    EPA Science Inventory

    Risk assessments have traditionally been developed on a chemical-by-chemical basis. However, regulatory agencies recently have been considering cumulative effects of chemicals that act via a common mechanism of toxicity. Here we present data on several mixture studies of chemic...

  12. Chemical analyses of soil samples collected from the Sandia National Laboratories, New Mexico environs, 1993-2005.

    SciTech Connect

    Deola, Regina Anne; Oldewage, Hans D.; Herrera, Heidi; Miller, Mark Laverne

    2006-03-01

    From 1993 through 2005, the Environmental Management Department of Sandia National Laboratories in Albuquerque, New Mexico (SNL/NM), has collected soil and sediment samples at numerous locations on-site, on the perimeter, and off-site for the purpose of determining potential impacts to the environs from operations at the Laboratories. These samples were submitted to an analytical laboratory for metal-in-soil analyses. Intercomparisons of these results were then made to determine if there was any statistical difference between on-site, perimeter, and off-site samples, or if there were year-to-year increasing or decreasing trends which indicated that further investigation may be warranted. This work provided the SNL Environmental Management Department with a sound baseline data reference against which to assess potential current operational impacts or to compare future operational impacts. In addition, it demonstrates the commitment that the Laboratories have to go beyond mere compliance to achieve excellence in its operations. This data is presented in graphical format with narrative commentaries on particular items of interest.

  13. Chemical analyses of soil samples collected from the Sandia National Laboratories, Kauai Test Facility, HI, 1999-2007.

    SciTech Connect

    Miller, Mark Laverne

    2007-11-01

    In 1999, 2002, and 2007, the Environmental Programs and Assurance Department of Sandia National Laboratories (SNL) at the Kauai Test Facility (KTF), HI, has collected soil samples at numerous locations on-site, on the perimeter, and off-site for determining potential impacts to the environs from operations at KTF. These samples were submitted to an analytical laboratory for metal-in-soil analyses. Intercomparisons of these results were then made to determine if there was any statistical difference between on-site, perimeter, and off-site samples, or if there were increasing or decreasing trends that indicated that further investigation might be warranted. This work provided the SNL Environmental Programs and Assurance Department with a sound baseline data reference against which to compare future operational impacts. In addition, it demonstrates the commitment that the Laboratories have to go beyond mere compliance to achieve excellence in its operations. This data is presented in graphical format with narrative commentaries on particular items of interest.

  14. Fermentation quality and chemical composition of shrub silage treated with lactic acid bacteria inoculants and cellulase additives.

    PubMed

    Sun, Qizhong; Gao, Fengqin; Yu, Zhu; Tao, Ya; Zhao, Shufen; Cai, Yimin

    2012-04-01

    Effects of lactic acid bacteria (LAB) inoculants and cellulase additives on fermentation quality and chemical compositions of shrub silages were studied by using a small-scale fermentation system. Two LAB inoculants of Qingbao (Lactobacillus plantarum, Pediococcus acidilacticii, Lactobacillus casei and Clostridium phage) and Caihe (Lactobacillus plantarum, Lactobacillus brevis and Pediococcus acidilactici) and a commercial cellulase made from Trichoderma reesei were used as additives for intermediate pea-shrub, rush bushclover, arborescent ceratoides and shrubby silage preparation. The crude protein, neutral detergent fiber and water-soluble carbohydrate contents of the four shrub materials were 10.1-14.2, 62.6-67.2 and 1.9-3.5% on a dry matter basis, respectively. All shrub silages had pH 3.40-4.43, ammonia-N 0.1-0.2% g/kg and lactic acid 1.3-2.9% on a fresh matter basis. The silage quality of LAB-inoculated silages did not have a greater effect than control silages, except shrubby silage preparation. Silages treated with the cellulase, the pH of rush bushclover and shrubby sweetvetch silage were significantly (P < 0.05) lower and the lactic acid content were significantly (P < 0.05) higher than the control silages. The results confirmed that shrub contained a relatively high content of crude protein; its silages can be preserved in good quality, and they are new potential resources for livestock feed. PMID:22515690

  15. Logical Positivism as a Tool to Analyse the Problem of Chemistry's Lack of Relevance in Secondary School Chemical Education

    ERIC Educational Resources Information Center

    Van Aalsvoort, Joke

    2004-01-01

    Secondary school chemical education has a problem: namely, the seeming irrelevance to the pupils of chemistry. Chemical education prepares pupils for participation in society. Therefore, it must imply a model of society, of chemistry, and of the relation between them. In this article it is hypothesized that logical positivism currently offers this…

  16. Effect of several additives and their admixtures on the physico-chemical properties of a calcium phosphate cement.

    PubMed

    Bohner, M; Merkle, H P; Landuyt, P V; Trophardy, G; Lemaitre, J

    2000-02-01

    Combinations of citrate (C6H5O(7)3-), pyrophosphate (P2O(7)4-) and sulfate (SO(4)2-) ions were used to modify the physico-chemical properties of a calcium phosphate cement (CPC) composed of beta-tricalcium phosphate (beta-TCP) and phosphoric acid (PA) solution. The results obtained with only one additive at a time are similar to those previously published. New facts are: the positive effect of C6H5O(7)3- ions on cement failure strain and their negative effect on cement pH. The position of the setting time maximum measured at an SO(4)2- concentration of 0.09 M was not displaced by the addition of C6H5O(7)3- and P2O(7)4- ions. However, the effect of SO(4)2- ions on the setting time was depressed by C6H5O(7)3- ions. Moreover, no increase in tensile strength was observed when increasing amounts of SO(4)2- were added into a C6H5O(7)3--containing cement. The latter results suggest a competitive effect of C6H5O(7)3- and SO(4)2- on setting time and tensile strength. Anhydrous dicalcium phosphate (DCP; CaHPO4) appeared in cement samples dried just after setting, but not in cement samples incubated for 24 h in deionized water before the drying step. It is believed that the setting reaction is stopped by the drying step, leaving a low internal pH in the sample, hence providing favorable conditions for the transformation of dicalcium phosphate dihydrate (DCPD) into DCP. Interestingly, even though C6H5O(7)3- ions dramatically lowered the equilibrium pH of the cement with 5 ml of deionized water, they still prevented the occurrence of the transformation of DCPD into DCP.

  17. Effect of an iodine-containing additive on the composition, structure, and morphology of chemically deposited lead selenide films

    NASA Astrophysics Data System (ADS)

    Smirnova, Z. I.; Bakanov, V. M.; Maskaeva, L. N.; Markov, V. F.; Voronin, V. I.

    2014-12-01

    The effect of an ammonium iodide additive on the elemental and phase compositions, structural parameters, and surface morphology of lead selenide films synthesized by chemical deposition from aqueous solutions has been studied using X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray analysis. It has been established that the obtained PbSe films have a multiphase structure. The iodine content of the films is directly proportional to the NH4I concentration in the reaction mixture and increases linearly with an increase in this concentration to 0.25 mol/L. No individual iodine-containing phases have been detected in the film structure. However, the introduction of iodine leads to an increase in the PbSe phase lattice parameter from ˜6.11 to ˜6.16 Å and to a decrease in the crystal grain size to ˜ 20 nm. It has been found that there is a correlation between the grain size, lattice parameter, and ammonium iodide concentration in the reaction mixture, which can be explained by changes in the film growth mechanism at the initial growth steps.

  18. Logical positivism as a tool to analyse the problem of chemistry's lack of relevance in secondary school chemical education

    NASA Astrophysics Data System (ADS)

    van Aalsvoort, Joke

    2004-09-01

    Secondary school chemical education has a problem: namely, the seeming irrelevance to the pupils of chemistry. Chemical education prepares pupils for participation in society. Therefore, it must imply a model of society, of chemistry, and of the relation between them. In this article it is hypothesized that logical positivism currently offers this model. Logical positivism is a philosophy of science that creates a divide between science and society. It is therefore further hypothesized that the adoption of logical positivism causes chemistry's lack of relevance in chemical education. Both hypotheses could be confirmed by an analysis of a grade nine course.

  19. The effect of chemical additives on the synthesis of ethanol. Technical progress report No. 4, June 16, 1988--September 15, 1988

    SciTech Connect

    Chuang, S.S.C.

    1988-11-14

    The objective of this research is to elucidate the role of various chemical additives on ethanol synthesis over Rh- and Ni-based catalysts. Chemical additives used for this study will include S, P, Ag, Cu, Mn, and Na which have different electronegativities. The effect of additives on the surface state of the catalysts, heat of adsorption of reactant molecules, reaction intermediates, reaction pathways, reaction kinetics, and product distributions is/will be investigated by a series of experimental studies including temperature programmed desorption, infrared study of NO adsorption, reactive probing, steady state rate measurement, and transient kinetic study. A better understanding of the role of additive on the synthesis reaction may allow us to use chemical additives to manipulate the catalytic properties of Rh- and Ni-based catalysts for producing high yields of ethanol from syngas.

  20. The effect of chemical additives on the synthesis of ethanol. Technical progress report No. 11, March 16, 1990--June 15, 1990

    SciTech Connect

    Chuang, S.S.C.

    1990-07-01

    The objective of this research is to elucidate the role of various chemical additives on ethanol synthesis over Rh- and Ni-based catalysts. Chemical additives used for this study will include S, P, Ag, Cu, Mn, and Na which have different electronegativities. The effect of additives on the surface state of the catalysts, heat of adsorption of reactant molecules, reaction intermediates, reaction pathways, reaction kinetics, and product distributions is/will be investigated by a series of experimental studies of NO adsorption, reaction probing, study state rate measurement, and transient kinetic study. A better understanding of the role of additive on the synthesis reaction may allow us to sue chemical additives to manipulate the catalytic properties of Rh- and Ni-based catalysts for producing high yields of ethanol from syngas. (VC)

  1. Analysing spatio-temporal patterns of the global NO2-distribution retrieved from GOME satellite observations using a generalized additive model

    NASA Astrophysics Data System (ADS)

    Hayn, M.; Beirle, S.; Hamprecht, F. A.; Platt, U.; Menze, B. H.; Wagner, T.

    2009-09-01

    With the increasing availability of observational data from different sources at a global level, joint analysis of these data is becoming especially attractive. For such an analysis - oftentimes with little prior knowledge about local and global interactions between the different observational variables at hand - an exploratory, data-driven analysis of the data may be of particular relevance. In the present work we used generalized additive models (GAM) in an exemplary study of spatio-temporal patterns in the tropospheric NO2-distribution derived from GOME satellite observations (1996 to 2001) at global scale. We focused on identifying correlations between NO2 and local wind fields, a quantity which is of particular interest in the analysis of spatio-temporal interactions. Formulating general functional, parametric relationships between the observed NO2 distribution and local wind fields, however, is difficult - if not impossible. So, rather than following a model-based analysis testing the data for predefined hypotheses (assuming, for example, sinusoidal seasonal trends), we used a GAM with non-parametric model terms to learn this functional relationship between NO2 and wind directly from the data. The NO2 observations showed to be affected by wind-dominated processes over large areas. We estimated the extent of areas affected by specific NO2 emission sources, and were able to highlight likely atmospheric transport "pathways". General temporal trends which were also part of our model - weekly, seasonal and linear changes - showed to be in good agreement with previous studies and alternative ways of analysing the time series. Overall, using a non-parametric model provided favorable means for a rapid inspection of this large spatio-temporal NO2 data set, with less bias than parametric approaches, and allowing to visualize dynamical processes of the NO2 distribution at a global scale.

  2. Impact of enzalutamide on quality of life in men with metastatic castration-resistant prostate cancer after chemotherapy: additional analyses from the AFFIRM randomized clinical trial

    PubMed Central

    Cella, D.; Ivanescu, C.; Holmstrom, S.; Bui, C. N.; Spalding, J.; Fizazi, K.

    2015-01-01

    Background To present longitudinal changes in Functional Assessment of Cancer Therapy-Prostate (FACT-P) scores during 25-week treatment with enzalutamide or placebo in men with progressive metastatic castration-resistant prostate cancer (mCRPC) after chemotherapy in the AFFIRM trial. Patients and methods Patients were randomly assigned to enzalutamide 160 mg/day or placebo. FACT-P was completed before randomization, at weeks 13, 17, 21, and 25, and every 12 weeks thereafter while on study treatment. Longitudinal changes in FACT-P scores from baseline to 25 weeks were analyzed using a mixed effects model for repeated measures (MMRM), with a pattern mixture model (PMM) applied as secondary analysis to address non-ignorable missing data. Cumulative distribution function (CDF) plots were generated and different methodological approaches and models for handling missing data were applied. Due to the exploratory nature of the analyses, adjustments for multiple comparisons were not made. AFFIRM is registered with ClinicalTrials.gov, number NCT00974311. Results The intention-to-treat FACT-P population included 938 patients (enzalutamide, n = 674; placebo n = 264) with evaluable FACT-P assessments at baseline and ≥1 post-baseline assessment. After 25 weeks, the mean FACT-P total score decreased by 1.52 points with enzalutamide compared with 13.73 points with placebo (P < 0.001). In addition, significant treatment differences at week 25 favoring enzalutamide were evident for all FACT-P subscales and indices, whether analyzed by MMRM or PMM. CDF plots revealed differences favoring enzalutamide compared with placebo across the full range of possible response levels for FACT-P total and all disease- and symptom-specific subscales/indices. Conclusion In men with progressive mCRPC after docetaxel-based chemotherapy, enzalutamide is superior to placebo in health-related quality-of-life outcomes, regardless of analysis model or threshold selected for meaningful response. Clinical

  3. Spacelab Charcoal Analyses

    NASA Technical Reports Server (NTRS)

    Slivon, L. E.; Hernon-Kenny, L. A.; Katona, V. R.; Dejarme, L. E.

    1995-01-01

    This report describes analytical methods and results obtained from chemical analysis of 31 charcoal samples in five sets. Each set was obtained from a single scrubber used to filter ambient air on board a Spacelab mission. Analysis of the charcoal samples was conducted by thermal desorption followed by gas chromatography/mass spectrometry (GC/MS). All samples were analyzed using identical methods. The method used for these analyses was able to detect compounds independent of their polarity or volatility. In addition to the charcoal samples, analyses of three Environmental Control and Life Support System (ECLSS) water samples were conducted specifically for trimethylamine.

  4. Variable Temperature Stress in the Nematode Caenorhabditis elegans (Maupas) and Its Implications for Sensitivity to an Additional Chemical Stressor.

    PubMed

    Cedergreen, Nina; Nørhave, Nils Jakob; Svendsen, Claus; Spurgeon, David J

    2016-01-01

    A wealth of studies has investigated how chemical sensitivity is affected by temperature, however, almost always under different constant rather than more realistic fluctuating regimes. Here we compared how the nematode Caenorhabditis elegans responds to copper at constant temperatures (8-24°C) and under fluctuation conditions of low (±4°C) and high (±8°C) amplitude (averages of 12, 16, 20°C and 16°C respectively). The DEBkiss model was used to interpret effects on energy budgets. Increasing constant temperature from 12-24°C reduced time to first egg, life-span and population growth rates consistent with temperature driven metabolic rate change. Responses at 8°C did not, however, accord with this pattern (including a deviation from the Temperature Size Rule), identifying a cold stress effect. High amplitude variation and low amplitude variation around a mean temperature of 12°C impacted reproduction and body size compared to nematodes kept at the matching average constant temperatures. Copper exposure affected reproduction, body size and life-span and consequently population growth. Sensitivity to copper (EC50 values), was similar at intermediate temperatures (12, 16, 20°C) and higher at 24°C and especially the innately stressful 8°C condition. Temperature variation did not increase copper sensitivity. Indeed under variable conditions including time at the stressful 8°C condition, sensitivity was reduced. DEBkiss identified increased maintenance costs and increased assimilation as possible mechanisms for cold and higher copper concentration effects. Model analysis of combined variable temperature effects, however, demonstrated no additional joint stressor response. Hence, concerns that exposure to temperature fluctuations may sensitise species to co-stressor effects seem unfounded in this case.

  5. Variable Temperature Stress in the Nematode Caenorhabditis elegans (Maupas) and Its Implications for Sensitivity to an Additional Chemical Stressor.

    PubMed

    Cedergreen, Nina; Nørhave, Nils Jakob; Svendsen, Claus; Spurgeon, David J

    2016-01-01

    A wealth of studies has investigated how chemical sensitivity is affected by temperature, however, almost always under different constant rather than more realistic fluctuating regimes. Here we compared how the nematode Caenorhabditis elegans responds to copper at constant temperatures (8-24°C) and under fluctuation conditions of low (±4°C) and high (±8°C) amplitude (averages of 12, 16, 20°C and 16°C respectively). The DEBkiss model was used to interpret effects on energy budgets. Increasing constant temperature from 12-24°C reduced time to first egg, life-span and population growth rates consistent with temperature driven metabolic rate change. Responses at 8°C did not, however, accord with this pattern (including a deviation from the Temperature Size Rule), identifying a cold stress effect. High amplitude variation and low amplitude variation around a mean temperature of 12°C impacted reproduction and body size compared to nematodes kept at the matching average constant temperatures. Copper exposure affected reproduction, body size and life-span and consequently population growth. Sensitivity to copper (EC50 values), was similar at intermediate temperatures (12, 16, 20°C) and higher at 24°C and especially the innately stressful 8°C condition. Temperature variation did not increase copper sensitivity. Indeed under variable conditions including time at the stressful 8°C condition, sensitivity was reduced. DEBkiss identified increased maintenance costs and increased assimilation as possible mechanisms for cold and higher copper concentration effects. Model analysis of combined variable temperature effects, however, demonstrated no additional joint stressor response. Hence, concerns that exposure to temperature fluctuations may sensitise species to co-stressor effects seem unfounded in this case. PMID:26784453

  6. Variable Temperature Stress in the Nematode Caenorhabditis elegans (Maupas) and Its Implications for Sensitivity to an Additional Chemical Stressor

    PubMed Central

    Svendsen, Claus; Spurgeon, David J.

    2016-01-01

    A wealth of studies has investigated how chemical sensitivity is affected by temperature, however, almost always under different constant rather than more realistic fluctuating regimes. Here we compared how the nematode Caenorhabditis elegans responds to copper at constant temperatures (8–24°C) and under fluctuation conditions of low (±4°C) and high (±8°C) amplitude (averages of 12, 16, 20°C and 16°C respectively). The DEBkiss model was used to interpret effects on energy budgets. Increasing constant temperature from 12–24°C reduced time to first egg, life-span and population growth rates consistent with temperature driven metabolic rate change. Responses at 8°C did not, however, accord with this pattern (including a deviation from the Temperature Size Rule), identifying a cold stress effect. High amplitude variation and low amplitude variation around a mean temperature of 12°C impacted reproduction and body size compared to nematodes kept at the matching average constant temperatures. Copper exposure affected reproduction, body size and life-span and consequently population growth. Sensitivity to copper (EC50 values), was similar at intermediate temperatures (12, 16, 20°C) and higher at 24°C and especially the innately stressful 8°C condition. Temperature variation did not increase copper sensitivity. Indeed under variable conditions including time at the stressful 8°C condition, sensitivity was reduced. DEBkiss identified increased maintenance costs and increased assimilation as possible mechanisms for cold and higher copper concentration effects. Model analysis of combined variable temperature effects, however, demonstrated no additional joint stressor response. Hence, concerns that exposure to temperature fluctuations may sensitise species to co-stressor effects seem unfounded in this case. PMID:26784453

  7. GRANNY, a data bank of chemical analyses of Laramide and younger high-silica rhyolites and granites from Colorado and north-central New Mexico

    USGS Publications Warehouse

    Steigerwald, Celia H.; Mutschler, Felix E.; Ludington, Steve

    1983-01-01

    GRANNY is a data bank containing information on 507 chemically analyzed Laramide or younger high-silica rhyolites and granites from Colorado and north-central New Mexico. The data were compiled from both published and unpublished sources. The data bank is designed to aid in the recognition of igneous rocks with a high exploration potential for the discovery of molybdenum (and other lithophile element) deposits. Information on source reference, geographic location, age, mineralogic and petrologic characteristics, major constituent analyses, and trace element analyses for each sample are given. The data bank is available in two formats: 1) paper- or microfiche-hardcopy, and 2) fixed format computer readable magnetic tape.

  8. Results of Water and Sediment Toxicity Tests and Chemical Analyses Conducted at the Central Shops Burning Rubble Pit Waste Unit, January 1999

    SciTech Connect

    Specht, W.L.

    1999-06-02

    The Central Shops Burning Rubble Pit Operable Unit consists of two inactive rubble pits (631-1G and 631-3G) that have been capped, and one active burning rubble pit (631-2G), where wooden pallets and other non-hazardous debris are periodically burned. The inactive rubble pits may have received hazardous materials, such as asbestos, batteries, and paint cans, as well as non-hazardous materials, such as ash, paper, and glass. In an effort to determine if long term surface water flows of potentially contaminated water from the 631-1G, 631-3G, and 631-2G areas have resulted in an accumulation of chemical constituents at toxic levels in the vicinity of the settling basin and wetlands area, chemical analyses for significant ecological preliminary constituents of concern (pCOCs) were performed on aqueous and sediment samples. In addition, aquatic and sediment toxicity tests were performed in accordance with U.S. EPA methods (U.S. EPA 1989, 1994). Based on the results of the chemical analyses, unfiltered water samples collected from a wetland and settling basins located adjacent to the CSBRP Operable Unit exceed Toxicity Reference Values (TRVs) for aluminum, barium, chromium, copper, iron, lead, and vanadium at one or more of the four locations that were sampled. The water contained very high concentrations of clay particles that were present as suspended solids. A substantial portion of the metals were present as filterable particulates, bound to the clay particles, and were therefore not biologically available. Based on dissolved metal concentrations, the wetland and settling basin exceeded TRVs for aluminum and barium. However, the background reference location also exceeded the TRV for barium, which suggests that this value may be too low, based on local geochemistry. The detection limits for both total and dissolved mercury were higher than the TRV, so it was not possible to determine if the TRV for mercury was exceeded. Dissolved metal levels of chromium, copper

  9. Burst and Principal Components Analyses of MEA Data for 16 Chemicals Describe at Least Three Effects Classes.

    EPA Science Inventory

    Microelectrode arrays (MEAs) detect drug and chemical induced changes in neuronal network function and have been used for neurotoxicity screening. As a proof-•of-concept, the current study assessed the utility of analytical "fingerprinting" using Principal Components Analysis (P...

  10. Sensory and chemical flavor analyses of tomato genotypes grown in Florida during three different growing seasons in multiple years

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thirty-eight tomato genotypes were analyzed for sensory attributes “sweet”, “sour” and “overall flavor” over seven years, one to three seasons per year (March, June and December) as well as for physical and chemical flavor-related attributes including color, sugars, acids and aroma volatiles (6-7 ye...

  11. Analysis on Soil Seed Bank Diversity Characteristics and Its Relation with Soil Physical and Chemical Properties after Substrate Addition

    PubMed Central

    He, Mengxuan; Lv, Lingyue; Li, Hongyuan; Meng, Weiqing; Zhao, Na

    2016-01-01

    Aims Considered as an essential measure in the application of soil seed bank (SSB) projects, the mixing of substrate and surface soil can effectively improve soil condition. This research is aimed at exploring the diversity characteristics of SSBs and the relationships between SSBs and soil properties. Methods Canonical correspondence analysis (CCA) was adopted to describe the ordination of SSBs on soil properties’ gradients; multiple linear regressions were adopted to analyze the relationship between average growth height and soil properties, density and soil properties. Results Experimental groups of mixed substrate (the mixture of organic and inorganic substrates) had high diversity indexes, especially the Shannon-Wiener Index compared with those of single substrate. Meanwhile, a higher number of species and increased density were also noted in those of mixed substrate. The best test group, No.16, had the highest diversity indexes with a Shannon-Wiener of 1.898, Simpson of 0.633 and Pielou of 0.717, and also showed the highest density of 14000 germinants /m2 and 21 species. In addition, an improvement of the soil’s chemical and physical properties was noted when the substrates were mixed. The mixed substrate of turfy soil and perlite could effectively enhance the soil moisture content, whilst a mixed substrate of rice husk carbon and vermiculite could improve the content of available potassium (AK) and phosphorus (AP) and strengthen soil fertility. The germinated plants also reflected obvious regularities of ordination on soil factor gradients. Three distinct cluster groups were presented, of which the first cluster was distributed in an area with a relatively higher content of AK and AP; the second cluster was distributed at places with relatively higher soil moisture content; and the third cluster of plants didn’t show any obvious relationship with soil physical and chemical properties. Through CCA analysis, AK and AP were considered the most important

  12. Two-stage coal liquefaction process materials from the Wilsonville Facility operated in the nonintegrated and integrated modes: chemical analyses and biological testing

    SciTech Connect

    Later, D.W.

    1985-01-01

    This document reports the results from chemical analyses and biological testing of process materials sampled during operation of the Wilsonville Advanced Coal Liquefaction Research and Development Facility (Wilsonville, Alabama) in both the noncoupled or nonintegrated (NTSL Run 241) and coupled or integrated (ITSL Run 242) two-stage liquefaction operating modes. Mutagenicity and carcinogenicity assays were conducted in conjunction with chromatographic and mass spectrometric analyses to provide detailed, comparative chemical and biological assessments of several NTSL and ITSL process materials. In general, the NTSL process materials were biologically more active and chemically more refractory than analogous ITSL process materials. To provide perspective, the NTSL and ITSL results are compared with those from similar testing and analyses of other direct coal liquefaction materials from the solvent refined coal (SRC) I, SRC II and EDS processes. Comparisons are also made between two-stage coal liquefaction materials from the Wilsonville pilot plant and the C.E. Lummus PDU-ITSL Facility in an effort to assess scale-up effects in these two similar processes. 36 references, 26 figures, 37 tables.

  13. Integrated Light Chemical Abundance Analyses of 7 M31 Outer Halo Globular Clusters from the Pan-Andromeda Archaeological Survey

    NASA Astrophysics Data System (ADS)

    Sakari, Charli; Venn, Kim; Mackey, Dougal; Shetrone, Matthew D.; Dotter, Aaron L.; Wallerstein, George

    2015-01-01

    Detailed chemical abundances of globular clusters provide insight into the formation and evolution of galaxies and their globular cluster systems. This talk presents detailed chemical abundances for seven M31 outer halo globular clusters (with projected radii greater than 30 kpc), as derived from high resolution integrated light spectra. Five of these clusters were recently discovered in the Pan-Andromeda Archaeological Survey (PAndAS). The integrated abundances show that 4 of these clusters are metal-poor ([Fe/H] < -1.5) while the other 3 are more metal-rich. The most metal-poor globular clusters are α-enhanced, though 3 of the 4 are possibly less α-enhanced than MW stars (at the 1σ level). Other chemical abundance ratios ([Ba/Eu], [Eu/Ca], and [Ni/Fe]) are consistent with origins in low mass dwarf galaxies (similar to Fornax). The most metal-rich cluster ([Fe/H] ~ -1) stands out as being chemically distinct from Milky Way field stars of the same metallicity---its chemical abundance ratios agree best with the stars and clusters in the Large Magellanic Cloud (LMC) and the Sagittarius dwarf spheroidal (Sgr) than with the Milky Way field stars. The other metal-rich clusters, H10 and H23, look similar to the LMC and Milky Way field stars in all abundance ratios. These results indicate that M31's outer halo is being at least partially built up by the accretion of dwarf satellites, in agreement with previous observations.

  14. Linking field-based metabolomics and chemical analyses to identify contaminants of emerging concern in the Great Lakes ecosystem

    EPA Science Inventory

    Although research has focused on remediating ecological impacts of environmental contaminants on the Great Lakes and other aquatic ecosystems, there exists a continuing need for additional biologically-based tools for monitoring success. Profiling of endogenous metabolites (i.e....

  15. Major and EDXRF Trace Element Chemical Analyses of Volcanic Rocks from Lassen Volcanic National Park and Vicinity, California

    USGS Publications Warehouse

    Clynne, Michael A.; Muffler, L.J.P.; Siems, D.F.; Taggart, J.E.; Bruggman, Peggy

    2008-01-01

    This open-file report presents WDXRF major-element chemical data for late Pliocene to Holocene volcanic rocks collected from Lassen Volcanic National Park and vicinity, California. Data for Rb, Sr, Ba, Y, Zr, Nb, Ni, Cr, Zn and Cu obtained by EDXRF are included for many samples. Data are presented in an EXCEL spreadsheet and are keyed to rock units as displayed on the Geologic Map of Lassen Volcanic National Park and vicinity (Clynne and Muffler, in press). Location of the samples is given in latitude and longitude in degrees and decimal minutes and in decimal degrees.

  16. Mechanical and chemical analyses across dental porcelain fused to CP titanium or Ti6Al4V.

    PubMed

    Souza, Júlio C M; Henriques, Bruno; Ariza, Edith; Martinelli, Antonio E; Nascimento, Rubens M; Silva, Filipe S; Rocha, Luís A; Celis, Jean-Pierre

    2014-04-01

    The aim of this study was to evaluate the evolution of mechanical properties and chemical variation across veneering dental porcelain fused to different titanium-based substrates. Test samples were synthesized by fusing dental feldspar-based porcelain onto commercially pure titanium grade II or Ti6Al4V alloy. Samples were cross-sectioned at angles of 10 and 90° to the interface plane. Afterwards, nanoindentation tests and Scanning Electron Microscopy (SEM) imaging coupled to an Energy Dispersive Spectroscopy (EDS) system were carried out across interfaces extending from the metal towards the porcelain area. Elemental diffusion profiles across the porcelain-to-metal interfaces were also obtained by EDS analysis. The mismatch in mechanical properties found in porcelain-to-Ti6Al4V interfaces was lower than that of porcelain-to-CP titanium. Cracking was noticed at low-thickness veneering dental porcelain regions after the nanoindentation tests of samples cross-sectioned at low angles to the interface plane. A wide reaction zone between titanium and porcelain as well as higher incidence of defects was noticed at the porcelain-to-CP titanium interfaces. This study confirmed Ti6Al4V as an improved alternative to CP-titanium as it showed to establish a better interface with the veneering dental porcelain considering the slight chemical interaction and the lower mechanical properties mismatch. The elastic modulus of porcelain-to-Ti6Al4V samples showed to be less sensitive to porcelain thickness variations.

  17. The Use of Additives to Control the Morphology of Thin Films Synthesized Using Aerosol Assisted Chemical Vapour Deposition

    NASA Astrophysics Data System (ADS)

    Kaye, Karl; Turner, David; McKenna, David; Cackett, Adam; Hyett, Geoffrey

    This paper identifies and discusses the use of additives to control the morphology of nanoscale crystalline zinc oxide films, grown using AACVD, principally from a solution of zinc acetate in methanol. We will discuss the use of both positively charged additives such as tetramethylammonium bromide and cetyltrimethylammonium bromide as well as negatively charged additives like sodium dodecylsulphate. Additives such as these, combined with other experimental parameters such as deposition time, have allowed us to control the size of the particles (from 100 to 400 nm in diameter), their orientation, and the regularity of their shape, from rough edged plates to well defined hexagons. We will show that the additives can be used to control morphology consistently over a temperature range of 250-400 °C, and that this technique can be applied generally to a number of additives and solvents.

  18. Combined Quantum Chemical/Raman Spectroscopic Analyses of Li+ Cation Solvation: Cyclic Carbonate Solvents - Ethylene Carbonate and Propylene Earbonate

    SciTech Connect

    Allen, Joshua L.; Borodin, Oleg; Seo, D. M.; Henderson, Wesley A.

    2014-12-01

    Combined computational/Raman spectroscopic analyses of ethylene carbonate (EC) and propylene carbonate (PC) solvation interactions with lithium salts are reported. It is proposed that previously reported Raman analyses of (EC)n-LiX mixtures have utilized faulty assumptions. In the present studies, density functional theory (DFT) calculations have provided corrections in terms of both the scaling factors for the solvent's Raman band intensity variations and information about band overlap. By accounting for these factors, the solvation numbers obtained from two different EC solvent bands are in excellent agreement with one another. The same analysis for PC, however, was found to be quite challenging. Commercially available PC is a racemic mixture of (S)- and (R)-PC isomers. Based upon the quantum chemistry calculations, each of these solvent isomers may exist as multiple conformers due to a low energy barrier for ring inversion, making deconvolution of the Raman bands daunting and inherently prone to significant error. Thus, Raman spectroscopy is able to accurately determine the extent of the EC...Li+ cation solvation interactions using the provided methodology, but a similar analysis of PC...Li+ cation solvation results in a significant underestimation of the actual solvation numbers.

  19. Ambient Monitoring for Sinclair and Dyes Inlets, Puget Sound, Washington: Chemical Analyses for 2010 Regional Mussel Watch (AMB02)

    SciTech Connect

    Brandenberger, Jill M.; Kuo, Li-Jung; Suslick, Carolynn R.; Johnston, Robert K.

    2010-10-20

    The Puget Sound Naval Shipyard & Intermediate Maintenance Facility (PSNS&IMF) and Naval Base Kitsap-Bremerton (Shipyard) located in Bremerton, WA are committed to a culture of continuous process improvement for all aspects of Shipyard operations, including reducing the releases of hazardous materials and waste in discharges from the Shipyard. Under the Project ENVVEST Final Project Agreement, a cooperative project among PSNS&IMF, the Environmental Protection Agency (EPA), and the Washington State Department of Ecology (Ecology), and local stakeholders (US Navy, EPA and Ecology 2002) has been helping to improve the environmental quality of the Sinclair and Dyes Inlet Watershed (ENVVEST 2006). An ambient monitoring program for sediment, water, and indigenous mussels began in 2009 to assess the status and trend of ecological resources, assess the effectiveness of cleanup and pollution control measures, and determine if discharges from all sources are protective of beneficial uses including aquatic life. This document presents the 2010 chemical residue data and stable isotopes of carbon (δ13C) and nitrogen (δ15N) for the regional mussel watch stations located in Sinclair Inlet, Dyes Inlet, Port Orchard Passage, Rich Passage, Agate Passage, Liberty Bay, and Keyport Lagoon. Indigenous bivalves were collected from a small boat and/or from along the shoreline, measured, composited, and analyzed for a suite of trace metals and organic contaminants. The trace metals included silver, arsenic, cadmium, chromium, copper, mercury, nickel, lead, and zinc. The organic contaminants included the list of NOAA Status and Trends 20 polychlorinated biphenyls (PCB) congeners and suite of parent and methylated polycyclic aromatic hydrocarbons (PAHs). These chemical residue data provide the first year of the biota ambient monitoring.

  20. Reduction of Large Detailed Chemical Kinetic Mechanisms for Autoignition Using Joint Analyses of Reaction Rates and Sensitivities

    SciTech Connect

    Saylam, A; Ribaucour, M; Pitz, W J; Minetti, R

    2006-11-29

    A new technique of reduction of detailed mechanisms for autoignition, which is based on two analysis methods is described. An analysis of reaction rates is coupled to an analysis of reaction sensitivity for the detection of redundant reactions. Thresholds associated with the two analyses have a great influence on the size and efficiency of the reduced mechanism. Rules of selection of the thresholds are defined. The reduction technique has been successfully applied to detailed autoignition mechanisms of two reference hydrocarbons: n-heptane and iso-octane. The efficiency of the technique and the ability of the reduced mechanisms to reproduce well the results generated by the full mechanism are discussed. A speedup of calculations by a factor of 5.9 for n-heptane mechanism and by a factor of 16.7 for iso-octane mechanism is obtained without losing accuracy of the prediction of autoignition delay times and concentrations of intermediate species.

  1. Characterization of microbial and chemical composition of shuttle wet waste with permanent gas and volatile organic compound analyses.

    PubMed

    Peterson, B V; Hummerick, M; Roberts, M S; Krumins, V; Kish, A L; Garland, J L; Maxwell, S; Mills, A

    2004-01-01

    Solid-waste treatment in space for Advanced Life Support, ALS, applications requires that the material can be safely processed and stored in a confined environment. Many solid-wastes are not stable because they are wet (40-90% moisture) and contain levels of soluble organic compounds that can contribute to the growth of undesirable microorganisms with concomitant production of noxious odors. In the absence of integrated Advanced Life Support systems on orbit, permanent gas, trace volatile organic and microbiological analyses were performed on crew refuse returned from the volume F "wet" trash of three consecutive Shuttle missions (STS-105, 109, and 110). These analyses were designed to characterize the short-term biological stability of the material and assess potential crew risks resulting from microbial decay processes during storage. Waste samples were collected post-orbiter landing and sorted into packaging material, food waste, toilet waste, and bulk liquid fractions deposited during flight in the volume F container. Aerobic and anaerobic microbial loads were determined in each fraction by cultivation on R2A and by acridine orange direct count (AODC). Dry and ash weights were performed to determine both water and organic content of the materials. Experiments to determine the aerobic and anaerobic biostability of refuse stored for varying periods of time were performed by on-line monitoring of CO2 and laboratory analysis for production of hydrogen sulfide and methane. Volatile organic compounds and permanent gases were analyzed using EPA Method TO15 by USEPA et al. [EPA Method TO15, The Determination of Volatile Organic Compounds (VOCs) in Ambient Air using SUMMA, Passivated Canister Sampling and Gas Chromatographic Analysis,1999] with gas chromatography/mass spectrometry and by gas chromatography with selective detectors. These baseline measures of waste stream content, labile organics, and microbial load in the volume F Shuttle trash provide data for waste

  2. Characterization of microbial and chemical composition of shuttle wet waste with permanent gas and volatile organic compound analyses

    NASA Technical Reports Server (NTRS)

    Peterson, B. V.; Hummerick, M.; Roberts, M. S.; Krumins, V.; Kish, A. L.; Garland, J. L.; Maxwell, S.; Mills, A.

    2004-01-01

    Solid-waste treatment in space for Advanced Life Support, ALS, applications requires that the material can be safely processed and stored in a confined environment. Many solid-wastes are not stable because they are wet (40-90% moisture) and contain levels of soluble organic compounds that can contribute to the growth of undesirable microorganisms with concomitant production of noxious odors. In the absence of integrated Advanced Life Support systems on orbit, permanent gas, trace volatile organic and microbiological analyses were performed on crew refuse returned from the volume F "wet" trash of three consecutive Shuttle missions (STS-105, 109, and 110). These analyses were designed to characterize the short-term biological stability of the material and assess potential crew risks resulting from microbial decay processes during storage. Waste samples were collected post-orbiter landing and sorted into packaging material, food waste, toilet waste, and bulk liquid fractions deposited during flight in the volume F container. Aerobic and anaerobic microbial loads were determined in each fraction by cultivation on R2A and by acridine orange direct count (AODC). Dry and ash weights were performed to determine both water and organic content of the materials. Experiments to determine the aerobic and anaerobic biostability of refuse stored for varying periods of time were performed by on-line monitoring of CO2 and laboratory analysis for production of hydrogen sulfide and methane. Volatile organic compounds and permanent gases were analyzed using EPA Method TO15 by USEPA et al. [EPA Method TO15, The Determination of Volatile Organic Compounds (VOCs) in Ambient Air using SUMMA, Passivated Canister Sampling and Gas Chromatographic Analysis,1999] with gas chromatography/mass spectrometry and by gas chromatography with selective detectors. These baseline measures of waste stream content, labile organics, and microbial load in the volume F Shuttle trash provide data for waste

  3. Characterization of microbial and chemical composition of shuttle wet waste with permanent gas and volatile organic compound analyses

    NASA Astrophysics Data System (ADS)

    Peterson, B. V.; Hummerick, M.; Roberts, M. S.; Krumins, V.; Kish, A. L.; Garland, J. L.; Maxwell, S.; Mills, A.

    2004-01-01

    Solid-waste treatment in space for Advanced Life Support, ALS, applications requires that the material can be safely processed and stored in a confined environment. Many solid-wastes are not stable because they are wet (40-90% moisture) and contain levels of soluble organic compounds that can contribute to the growth of undesirable microorganisms with concomitant production of noxious odors. In the absence of integrated Advanced Life Support systems on orbit, permanent gas, trace volatile organic and microbiological analyses were performed on crew refuse returned from the volume F "wet" trash of three consecutive Shuttle missions (STS-105, 109, and 110). These analyses were designed to characterize the short-term biological stability of the material and assess potential crew risks resulting from microbial decay processes during storage. Waste samples were collected post-orbiter landing and sorted into packaging material, food waste, toilet waste, and bulk liquid fractions deposited during flight in the volume F container. Aerobic and anaerobic microbial loads were determined in each fraction by cultivation on R2A and by acridine orange direct count (AODC). Dry and ash weights were performed to determine both water and organic content of the materials. Experiments to determine the aerobic and anaerobic biostability of refuse stored for varying periods of time were performed by on-line monitoring of CO 2 and laboratory analysis for production of hydrogen sulfide and methane. Volatile organic compounds and permanent gases were analyzed using EPA Method TO15 by USEPA et al. [EPA Method TO15, The Determination of Volatile Organic Compounds (VOCs) in Ambient Air using SUMMA, Passivated Canister Sampling and Gas Chromatographic Analysis, 1999] with gas chromatography/mass spectrometry and by gas chromatography with selective detectors. These baseline measures of waste stream content, labile organics, and microbial load in the volume F Shuttle trash provide data for waste

  4. Performance and Loss Analyses of High-Efficiency Chemical Bath Deposition (CBD)-ZnS/Cu(In1-xGax)Se2 Thin-Film Solar Cells

    NASA Astrophysics Data System (ADS)

    Pudov, Alexei; Sites, James; Nakada, Tokio

    2002-06-01

    Chemically deposited ZnS has been investigated as a buffer layer alternative to cadmium sulfide (CdS) in polycrystalline thin-film Cu(In1-xGax)Se2 (CIGS) solar cells. Cells with efficiency of up to 18.1% based on chemical bath deposition (CBD)-ZnS{\\slash}CIGS heterostructures have been fabricated. This paper presents the performance and loss analyses of these cells based on the current-voltage (J-V) and spectral response curves, as well as comparisons with high efficiency CBD-CdS/CIGS and crystalline silicon counterparts. The CBD-ZnS/CIGS devices have effectively reached the efficiency of the current record CBD-CdS/CIGS cell. The effects of the superior current of the CBD-ZnS/CIGS cell and the superior junction quality of the CBD-CdS/CIGS cell on overall performance nearly cancel each other.

  5. Eastern Gas Shales Project: Dow Chemical wells No. 100, No. 103, and No. 205. Phase III report, summary of laboratory analyses and mechanical characterization results

    SciTech Connect

    1981-12-01

    This summary presents a detailed characterization of the Devonian Shale occurrence in the Dow Chemical No. 100, No. 103, and No. 205 wells. Information provided includes a stratigraphic summary and lithology and fracture analyses resulting from detailed core examinations and geophysical log interpretations at the EGSP Core Laboratory. Plane of weakness orientations stemming from a program of physical properties testing on samples from the Dow Chemical No. 103 core at Michigan Technological University are also summarized; the results of physical properties testing are dealth with in detail in the accompanying report. The data presented was obtained from the study of approximately 617 feet of core retrieved from several wells drilled in Sanilac County of east-central Michigan.

  6. Assessing the ecological long-term impact of wastewater irrigation on soil and water based on bioassays and chemical analyses.

    PubMed

    Richter, Elisabeth; Hecht, Fabian; Schnellbacher, Nadine; Ternes, Thomas A; Wick, Arne; Wode, Florian; Coors, Anja

    2015-11-01

    The reuse of treated wastewater for irrigation and groundwater recharge can counteract water scarcity and reduce pollution of surface waters, but assessing its environmental risk should likewise consider effects associated to the soil. The present study therefore aimed at determining the impact of wastewater irrigation on the habitat quality of water after soil passage and of soil after percolation by applying bioassays and chemical analysis. Lab-scale columns of four different soils encompassing standard European soil and three field soils of varying characteristics and pre-contamination were continuously percolated with treated wastewater to simulate long-term irrigation. Wastewater and its percolates were tested for immobilization of Daphnia magna and growth inhibition of green algae (Pseudokirchneriella subcapitata) and water lentils (Lemna minor). The observed phytotoxicity of the treated wastewater was mostly reduced by soil passage, but in some percolates also increased for green algae. Chemical analysis covering an extensive set of wastewater-born organic pollutants demonstrated that many of them were considerably reduced by soil passage, particularly through peaty soils. Taken together, these results indicated that wastewater-born phytotoxic substances may be removed by soil passage, while existing soil pollutants (e.g. metals) may leach and impair percolate quality. Soils with and without wastewater irrigation were tested for growth of plants (Avena sativa, Brassica napus) and soil bacteria (Arthrobacter globiformis) and reproduction of collembolans (Folsomia candida) and oligochaetes (Enchytraeus crypticus, Eisenia fetida). The habitat quality of the standard and two field soils appeared to be deteriorated by wastewater percolation for at least one organism (enchytraeids, plants or bacteria), while for two pre-contaminated field soils it also was improved (for plants and/or enchytraeids). Wastewater percolation did not seem to raise soil concentrations

  7. Evidence for ships emissions in the Central Mediterranean Sea from aerosol chemical analyses at the island of Lampedusa

    NASA Astrophysics Data System (ADS)

    Becagli, S.; Sferlazzo, D. M.; Pace, G.; di Sarra, A.; Bommarito, C.; Calzolai, G.; Ghedini, C.; Lucarelli, F.; Meloni, D.; Monteleone, F.; Severi, M.; Traversi, R.; Udisti, R.

    2011-11-01

    Measurements of aerosol chemical composition made on the island of Lampedusa, south of the Sicily channel, during years 2004-2008, are used to identify the influence of ship emissions on aerosol particles in the Central Mediterranean. Evidence of ship emissions influence is found in 17% of the daily samples. Aerosol samples influenced by ships are characterized by elevated Ni and V soluble fraction (about 80% for aerosol from ships, versus about 40 % for crustal particles), high V and Ni to Si ratios, and values of Vsol>6 ng m-3. Back trajectories analysis on the selected events show that air masses prevalently come from the Sicily channel, where an intense ship traffic occurs. Vsol, Nisol, and non-sea salt SO42- (nssSO42-) show a marked seasonal behaviour, with an evident summer maximum. Such a pattern can be explained by several processes: (i) increased photochemical activity in summer, leading to a faster production of secondary aerosols, mainly nssSO42-, from the oxidation of SO2 in the ship plume; (ii) stronger marine boundary layer (MBL) stability in summer, leading to higher concentration of emitted compounds in the lowest atmospheric layers; (iii) more frequent meteorological conditions leading to consecutive days with trajectories from the Sicily channel in summer. A very intense event in spring 2008 was studied in detail, also using size segregated chemical measurements. These data show that elements arising from heavy oil combustion (V, Ni, Al, Fe) are distributed in the sub-micrometric fraction of the aerosol, and the metals are present as free metals, carbonates, oxides hydrates or labile complex with organic ligands, so that they are dissolved in mild condition (HNO3, pH1.5). Data suggest a characteristic nssSO42-/V ratio in the range 200-400 for ship emission aerosols in summer at Lampedusa. By using the value of 200 a lower limit for the ship contribution to total sulphates is estimated. Ship emissions account, as a summer average, at least for 1

  8. Ambient Monitoring for Sinclair and Dyes Inlets, Puget Sound, Washington: Chemical Analyses for 2012 Regional Mussel Watch

    SciTech Connect

    Brandenberger, Jill M.; Kuo, Li-Jung; Suslick, Carolynn R.; Johnston, Robert K.

    2012-09-01

    Under the Project ENVVEST Final Project Agreement, the Puget Sound Naval Shipyard & Intermediate Maintenance Facility (PSNS&IMF), Environmental Protection Agency (EPA), Washington State Department of Ecology (Ecology), and local stakeholders have worked collaboratively to improve the environmental quality of Sinclair and Dyes Inlets. A regional mussel monitoring program began in 2010 to assess the status and trend of ecological resources, assess the effectiveness of cleanup and pollution control measures, and determine if discharges from all sources are protective of beneficial uses including aquatic life. The program collected indigenous mussels to represent a time-integrated measure of bioavailable metals and organic chemicals present in the water column. This document supplements the 2010 indigenous mussel data with 2012 data to provide two years of data on the chemical residue of mussels present in the inter-tidal regions of Sinclair Inlet, Dyes Inlet, Port Orchard Passage, Rich Passage, Agate Passage, Liberty Bay, and Keyport Lagoon. The 2012 data set added one station at PSNS&IMF and one market samples from Penn Cove. Indigenous mussels were collected from a small boat and/or from along the shoreline, measured, composited, and analyzed for percent lipids, percent moisture, stable isotopes of carbon and nitrogen, and a suite of trace metals and organic contaminants. The trace metals included silver (Ag), arsenic (As), cadmium (Cd), copper (Cu), mercury (Hg), lead (Pb), and zinc (Zn). The organic contaminants included the list of NOAA Status and Trends 20 polychlorinated biphenyls (PCB) congeners and suite of parent and methylated polycyclic aromatic hydrocarbons (PAHs). The average lengths between the 2010 and 2012 data were generally less than 30% relative percent difference (RPD). Generally, the metals concentrations were lower in 2012 than 2010 with some notable exceptions in Sinclair Inlet and Rich Passage where increases in Ag, Hg, Pb, Cu, and Zn exceeded

  9. Assessing the ecological long-term impact of wastewater irrigation on soil and water based on bioassays and chemical analyses.

    PubMed

    Richter, Elisabeth; Hecht, Fabian; Schnellbacher, Nadine; Ternes, Thomas A; Wick, Arne; Wode, Florian; Coors, Anja

    2015-11-01

    The reuse of treated wastewater for irrigation and groundwater recharge can counteract water scarcity and reduce pollution of surface waters, but assessing its environmental risk should likewise consider effects associated to the soil. The present study therefore aimed at determining the impact of wastewater irrigation on the habitat quality of water after soil passage and of soil after percolation by applying bioassays and chemical analysis. Lab-scale columns of four different soils encompassing standard European soil and three field soils of varying characteristics and pre-contamination were continuously percolated with treated wastewater to simulate long-term irrigation. Wastewater and its percolates were tested for immobilization of Daphnia magna and growth inhibition of green algae (Pseudokirchneriella subcapitata) and water lentils (Lemna minor). The observed phytotoxicity of the treated wastewater was mostly reduced by soil passage, but in some percolates also increased for green algae. Chemical analysis covering an extensive set of wastewater-born organic pollutants demonstrated that many of them were considerably reduced by soil passage, particularly through peaty soils. Taken together, these results indicated that wastewater-born phytotoxic substances may be removed by soil passage, while existing soil pollutants (e.g. metals) may leach and impair percolate quality. Soils with and without wastewater irrigation were tested for growth of plants (Avena sativa, Brassica napus) and soil bacteria (Arthrobacter globiformis) and reproduction of collembolans (Folsomia candida) and oligochaetes (Enchytraeus crypticus, Eisenia fetida). The habitat quality of the standard and two field soils appeared to be deteriorated by wastewater percolation for at least one organism (enchytraeids, plants or bacteria), while for two pre-contaminated field soils it also was improved (for plants and/or enchytraeids). Wastewater percolation did not seem to raise soil concentrations

  10. Chemical analyses of pore water from boreholes USW SD-6 and USW WT-24, Yucca Mountain, Nevada

    USGS Publications Warehouse

    Yang, I.C.; Peterman, Z.E.; Scofield, K.M.

    2003-01-01

    Analyses of pore water extracted from cores of boreholes USW SD-6 in the central part and USW WT-24 in the northern part of Yucca Mountain, Nevada, show significant vertical and lateral variations in dissolved-ion concentrations. Analyses of samples of only a few milliliters of pore water extracted by uniaxial or triaxial compression and by ultracentrifugation methods from adjacent core samples are generally in agreement, within the analytical error of 10% to 15%. However, the values of silica for water obtained by ultracentrifugation are consistently lower than values for water obtained by compression. The larger concentrations probably are due to localized pressure solution of silicate minerals during compression. The shallower water from core in borehole USW SD-6 was extracted from nonwelded units collectively referred to as the Paintbrush Tuff nonwelded (PTn). The deeper water was from core in both boreholes USW SD-6 and USW WT-24 in the nonwelded units referred to as the Calico Hills nonwelded (CHn). Significant differences in mean dissolved-ion concentrations in pore water between the PTn and CHn are (1) decreases in Ca, Mg, SO4, and NO3 and (2) increases in HCO3 and (Na+K)/(Ca+Mg) ratios. The decrease in NO3 and the increase in HCO3 could be the result of denitrification through the oxidation of organic matter. The decrease in Ca and associated increase in (Na+K)/(Ca+Mg) is the result of ion exchange with zeolites in the CHn in borehole USW WT-24. This effect is not nearly as pronounced in borehole USW SD-6, probably reflecting a smaller amount of zeolitization of the CHn in USW SD-6. Geochemical calculations using the PHREEQC code indicate that the pore water from both boreholes USW SD-6 and USW WT-24 is uniformly undersaturated in anhydrite, gypsum, and amorphous silica, but supersaturated in quartz and chalcedony. The saturation of calcite, aragonite, sepiolite, and dolomite is more variable from sample to sample. ?? 2002 Elsevier Science B.V. All rights

  11. Confirmatory chemical analyses and solid phase bioassays on sediment from the Columbia River Estuary at Tongue Point, Oregon

    SciTech Connect

    Young, J.S.; Word, J.Q.; Apts, C.W.; Barrows, M.E.; Cullinan, V.I.; Kohn, N.P.

    1988-12-01

    The Department of Economic Development, Ports Division, of the state of Oregon plans to develop a former ship supply and storage site near Tongue Point, Oregon, for commercial shipping. The development would require dredging the adjacent waterway to the Columbia River 40-foot channel to admit commercials vessels. The Portland District of the US Army Corps of Engineers requested the Battelle/Marine Sciences Laboratory (MSL) to conduct confirmatory solid-phase bioassays that would provide technical data for an evaluation of the potential environmental impact of ocean disposal of the dredged material. These confirmatory studies provided chemical and biological information required by ocean dumping regulations to determine suitability of Tongue Point sediments for ocean disposal. Sediment core samples were collected from Cathlamet Bay at Tongue Point in the upper Columbia River estuary. Sediment surface grab samples were collected at reference/control sites offshore from the mouth of the Columbia River (Disposal Site F) and at West Beach, Whidbey Island, Washington. The Tongue Point sediments were mixed into two composited batches. The MSL conducted solid-phase bioassays with these composites and reference sediments on four species of organisms.

  12. Chemical analyses of coal, coal-associated rocks and coal combustion products collected for the National Coal Quality Inventory

    USGS Publications Warehouse

    Hatch, Joseph R.; Bullock, John H.; Finkelman, Robert B.

    2006-01-01

    In 1999, the USGS initiated the National Coal Quality Inventory (NaCQI) project to address a need for quality information on coals that will be mined during the next 20-30 years. At the time this project was initiated, the publicly available USGS coal quality data was based on samples primarily collected and analyzed between 1973 and 1985. The primary objective of NaCQI was to create a database containing comprehensive, accurate and accessible chemical information on the quality of mined and prepared United States coals and their combustion byproducts. This objective was to be accomplished through maintaining the existing publicly available coal quality database, expanding the database through the acquisition of new samples from priority areas, and analysis of the samples using updated coal analytical chemistry procedures. Priorities for sampling include those areas where future sources of compliance coal are federally owned. This project was a cooperative effort between the U.S. Geological Survey (USGS), State geological surveys, universities, coal burning utilities, and the coal mining industry. Funding support came from the Electric Power Research Institute (EPRI) and the U.S. Department of Energy (DOE).

  13. Food additives

    PubMed Central

    Spencer, Michael

    1974-01-01

    Food additives are discussed from the food technology point of view. The reasons for their use are summarized: (1) to protect food from chemical and microbiological attack; (2) to even out seasonal supplies; (3) to improve their eating quality; (4) to improve their nutritional value. The various types of food additives are considered, e.g. colours, flavours, emulsifiers, bread and flour additives, preservatives, and nutritional additives. The paper concludes with consideration of those circumstances in which the use of additives is (a) justified and (b) unjustified. PMID:4467857

  14. Chemical analyses of hot springs, pools, geysers, and surface waters from Yellowstone National Park, Wyoming, and vicinity, 1974-1975

    USGS Publications Warehouse

    Ball, James W.; Nordstrom, D. Kirk; Jenne, Everett A.; Vivit, Davison V.

    1998-01-01

    This report presents all analytical determinations for samples collected from Yellowstone National Park and vicinity during 1974 and 1975. Water temperature, pH, Eh, and dissolved O2 were determined on-site. Total alkalinity and F were determined on the day of sample collection. Flame atomic-absorption spectrometry was used to determine concentrations of Li, Na, K, Ca, and Mg. Ultraviolet/visible spectrophotometry was used to determine concentrations of Fe(II), Fe(III), As(III), and As(V). Direct-current plasma-optical-emission spectrometry was used to determine the concentrations of B, Ba, Cd, Cs, Cu, Mn, Ni, Pb, Rb, Sr, and Zn. Two samples collected from Yellowstone Park in June 1974 were used as reference samples for testing the plasma analytical method. Results of these tests demonstrate acceptable precision for all detectable elements. Charge imbalance calculations revealed a small number of samples that may have been subject to measurement errors in pH or alkalinity. These data represent some of the most complete analyses of Yellowstone waters available.

  15. Additive-dominance genetic model analyses for late-maturity alpha-amylase activity in a bread wheat factorial crossing population.

    PubMed

    Rasul, Golam; Glover, Karl D; Krishnan, Padmanaban G; Wu, Jixiang; Berzonsky, William A; Ibrahim, Amir M H

    2015-12-01

    Elevated level of late maturity α-amylase activity (LMAA) can result in low falling number scores, reduced grain quality, and downgrade of wheat (Triticum aestivum L.) class. A mating population was developed by crossing parents with different levels of LMAA. The F2 and F3 hybrids and their parents were evaluated for LMAA, and data were analyzed using the R software package 'qgtools' integrated with an additive-dominance genetic model and a mixed linear model approach. Simulated results showed high testing powers for additive and additive × environment variances, and comparatively low powers for dominance and dominance × environment variances. All variance components and their proportions to the phenotypic variance for the parents and hybrids were significant except for the dominance × environment variance. The estimated narrow-sense heritability and broad-sense heritability for LMAA were 14 and 54%, respectively. High significant negative additive effects for parents suggest that spring wheat cultivars 'Lancer' and 'Chester' can serve as good general combiners, and that 'Kinsman' and 'Seri-82' had negative specific combining ability in some hybrids despite of their own significant positive additive effects, suggesting they can be used as parents to reduce LMAA levels. Seri-82 showed very good general combining ability effect when used as a male parent, indicating the importance of reciprocal effects. High significant negative dominance effects and high-parent heterosis for hybrids demonstrated that the specific hybrid combinations; Chester × Kinsman, 'Lerma52' × Lancer, Lerma52 × 'LoSprout' and 'Janz' × Seri-82 could be generated to produce cultivars with significantly reduced LMAA level.

  16. Bioassay of estrogenicity and chemical analyses of estrogens in streams across the United States associated with livestock operations

    USGS Publications Warehouse

    Alvarez, David A.; Shappell, Nancy W.; Billey, L.O.; Bermudez, Dietrich S.; Wilson, Vickie S.; Kolpin, Dana W.; Perkins, Stephanie D.; Evans, Nicola; Foreman, William T.; Gray, James L.; Shipitalo, J.M.; Meyer, Michael T.

    2013-01-01

    Animal manures, used as a nitrogen source for crop production, are often associated with negative impacts on nutrient levels in surface water. The concentrations of estrogens in streams from these manures also are of concern due to potential endocrine disruption in aquatic species. Streams associated with livestock operations were sampled by discrete samples (n = 38) or by time-integrated polar organic chemical integrative samplers (POCIS,n = 19). Samples were analyzed for estrogens by gas chromatography-tandem mass spectrometry (GC-MSM2) and estrogenic activity was assessed by three bioassays: Yeast Estrogen Screen (YES), T47D-KBluc Assay, MCF-7 Estrogenicity Screen (E-Screen). Samples were collected from 19 streams within small (∼1-30 km2) watersheds in 12 U.S. states representing a range of hydrogeologic conditions, dominated by: dairy (3), grazing beef (3), feedlot cattle (1); swine (5); poultry (3); and 4 areas where no livestock were raised or manure was applied. Water samples were consistently below the United Kingdom proposed Lowest Observable Effect Concentration for 17b-estradiol in fish (10 ng/L) in all watersheds, regardless of land use. Estrogenic activity was often higher in samples during runoff conditions following a period of manure application. Estrone was the most commonly detected estrogen (13 of 38 water samples, mean 1.9, maximum 8.3 ng/L). Because of the T47D-KBluc assay’s sensitivity towards estrone (1.4 times 17β-estradiol) it was the most sensitive method for detecting estrogens, followed by the E-Screen, GC-MS2, and YES. POCIS resulted in more frequent detections of estrogens than discrete water samples across all sites, even when applying the less-sensitive YES bioassay to the POCIS extracts.

  17. Bioassay of estrogenicity and chemical analyses of estrogens in streams across the United States associated with livestock operations.

    PubMed

    Alvarez, D A; Shappell, N W; Billey, L O; Bermudez, D S; Wilson, V S; Kolpin, D W; Perkins, S D; Evans, N; Foreman, W T; Gray, J L; Shipitalo, M J; Meyer, M T

    2013-06-15

    Animal manures, used as a nitrogen source for crop production, are often associated with negative impacts on nutrient levels in surface water. The concentrations of estrogens in streams from these manures also are of concern due to potential endocrine disruption in aquatic species. Streams associated with livestock operations were sampled by discrete samples (n = 38) or by time-integrated polar organic chemical integrative samplers (POCIS, n = 19). Samples were analyzed for estrogens by gas chromatography-tandem mass spectrometry (GC-MS(2)) and estrogenic activity was assessed by three bioassays: Yeast Estrogen Screen (YES), T47D-KBluc Assay, MCF-7 Estrogenicity Screen (E-Screen). Samples were collected from 19 streams within small (≈ 1-30 km(2)) watersheds in 12 U.S. states representing a range of hydrogeologic conditions, dominated by: dairy (3), grazing beef (3), feedlot cattle (1); swine (5); poultry (3); and 4 areas where no livestock were raised or manure was applied. Water samples were consistently below the United Kingdom proposed Lowest Observable Effect Concentration for 17β-estradiol in fish (10 ng/L) in all watersheds, regardless of land use. Estrogenic activity was often higher in samples during runoff conditions following a period of manure application. Estrone was the most commonly detected estrogen (13 of 38 water samples, mean 1.9, maximum 8.3 ng/L). Because of the T47D-KBluc assay's sensitivity towards estrone (1.4 times 17β-estradiol) it was the most sensitive method for detecting estrogens, followed by the E-Screen, GC-MS(2), and YES. POCIS resulted in more frequent detections of estrogens than discrete water samples across all sites, even when applying the less-sensitive YES bioassay to the POCIS extracts.

  18. Effects of N{sub 2} addition on chemical dry etching of silicon oxide layers in F{sub 2}/N{sub 2}/Ar remote plasmas

    SciTech Connect

    Hwang, J.Y.; Kim, D.J.; Lee, N.-E.; Jang, Y.C.; Bae, G.H.

    2006-07-15

    In this study, chemical dry etching characteristics of silicon oxide layers were investigated in the F{sub 2}/N{sub 2}/Ar remote plasmas. A toroidal-type remote plasma source was used for the generation of remote plasmas. The effects of additive N{sub 2} gas on the etch rates of various silicon oxide layers deposited using different deposition techniques and precursors were investigated by varying the various process parameters, such as the F{sub 2} flow rate, the additive N{sub 2} flow rate, and the substrate temperature. The etch rates of the various silicon oxide layers at room temperature were initially increased and then decreased with the N{sub 2} flow increased, which indicates an existence of the maximum etch rates. Increase in the oxide etch rates under the decreased optical emission intensity of the F radicals with the N{sub 2} flow increased implies that the chemical etching reaction is in the chemical reaction-limited regime, where the etch rate is governed by the surface chemical reaction rather than the F radical density. The etch rates of the silicon oxide layers were also significantly increased with the substrate temperature increased. In the present experiments, the F{sub 2} gas flow, the additive N{sub 2} flow rate, and the substrate temperature were found to be the critical parameters in determining the etch rate of the silicon oxide layers.

  19. Application of multivariate analysis to the effects of additives on chemical and sensory quality of stored coffee brew.

    PubMed

    Pérez-Martínez, Mónica; Sopelana, Patricia; de Peña, M Paz; Cid, Concepción

    2008-12-24

    The aim of this work was to obtain a black coffee brew to be consumed hot by extension of its shelf life, by addition of additives. Four pH-regulator agents (sodium and potassium carbonates and bicarbonates), one pH regulator and antioxidant (sodium citrate), three antioxidants [sodium ascorbate, ethylenediaminetetracetic acid (EDTA), and sodium sulfite], and lactoserum were tested by sensory analysis. Sodium carbonate and bicarbonate were selected for a study of the physicochemical (soluble and volatile compounds related to the sensory properties) and sensorial quality of coffee brew stored for 90 days at 4 degrees C. Although both additives extended the shelf life of the coffee brew up to 60 days, sodium carbonate was the chosen additive because it was the most useful in limiting the pH decrease and perception of sourness, which are some of the main factors involved in the rejection of stored coffee brews, and it better maintained the aroma and taste/flavor. Moreover, the application of multivariate analysis facilitated first the description of the global changes of the coffee brews with or without additives throughout the storage using principal component analysis and second the obtainment of a simple equation only with pH and caffeic acid parameters to discriminate the three types of coffee brews and simplify the analytical process, by means of the stepwise discriminant analysis.

  20. A quantum chemical study of the mechanisms of olefin addition to group 9 transition metal dioxo compounds.

    PubMed

    Ahmed, Issahaku; Tia, Richard; Adei, Evans

    2016-01-01

    The mechanistic aspects of ethylene addition to MO2(CH2)(CH3) (M=Co, Rh, Ir) have been investigated with a Hartree-Fock/DFT hybrid functional at the MO6/LACVP* and B3LYP/LACVP* levels of theory to elucidate the reaction pathways on the singlet, doublet and triplet potential energy surfaces (PES). In the reaction of the IrO2CH2CH3 complex with ethylene, [3 + 2]C,O addition is the most plausible pathway on the singlet PES, the [3 + 2]O,O addition is the most favoured pathway on the doublet surface whiles the stepwise [1 + 1] addition involving the oxygen atom of the complex in the first step and the carbon atom of the complex in the second step is the most plausible pathway on the triplet PES. For the reaction of the RhO2(CH2)(CH3) complex, the [2 + 2]Rh,O addition pathway is the most favoured on the singlet surface, the [2 + 2]Rh,C is the most plausible pathway on the triplet PES and [3 + 2]C,O is the most plausible on the doublet surface. For the reactions of the CoO2(CH2)(CH3) complex, the [1 + 2]O addition is the most plausible on the singlet PES, [3 + 2]C=Co=O cycloaddition to form the five-membered intermediate is the most preferred pathway on the doublet PES, whiles on the triplet PES the preferred pathway is the [3 + 2] addition across the O=Co=O bond of the metal complex. The reactions of olefins with the Co dioxo complex have lower activation barriers for the preferred [3 + 2] and [2 + 2] addition pathways as well as fewer side reactions than those of the rhodium and iridium systems. This could imply that the cobalt dioxo complexes can efficiently and selectively catalyze specific reactions in oxidation of olefins than Rh and Ir oxo complexes will do and therefore Co oxo complexes may be better catalysts for specific oxidation reactions of olefins than Rh and Ir complexes are. The activation barriers for the formation of the four-or five-membered metallacycle intermediates through [2 + 2] or [3 + 2] cyclo-addition are lower on the

  1. Novel Flow Cytometry Analyses of Boar Sperm Viability: Can the Addition of Whole Sperm-Rich Fraction Seminal Plasma to Frozen-Thawed Boar Sperm Affect It?

    PubMed Central

    Díaz, Rommy; Boguen, Rodrigo; Martins, Simone Maria Massami Kitamura; Ravagnani, Gisele Mouro; Leal, Diego Feitosa; Oliveira, Melissa de Lima; Muro, Bruno Bracco Donatelli; Parra, Beatriz Martins; Meirelles, Flávio Vieira; Papa, Frederico Ozanan; Dell’Aqua, José Antônio; Alvarenga, Marco Antônio; Moretti, Aníbal de Sant’Anna; Sepúlveda, Néstor

    2016-01-01

    Boar semen cryopreservation remains a challenge due to the extension of cold shock damage. Thus, many alternatives have emerged to improve the quality of frozen-thawed boar sperm. Although the use of seminal plasma arising from boar sperm-rich fraction (SP-SRF) has shown good efficacy; however, the majority of actual sperm evaluation techniques include a single or dual sperm parameter analysis, which overrates the real sperm viability. Within this context, this work was performed to introduce a sperm flow cytometry fourfold stain technique for simultaneous evaluation of plasma and acrosomal membrane integrity and mitochondrial membrane potential. We then used the sperm flow cytometry fourfold stain technique to study the effect of SP-SRF on frozen-thawed boar sperm and further evaluated the effect of this treatment on sperm movement, tyrosine phosphorylation and fertility rate (FR). The sperm fourfold stain technique is accurate (R2 = 0.9356, p > 0.01) for simultaneous evaluation of plasma and acrosomal membrane integrity and mitochondrial membrane potential (IPIAH cells). Centrifugation pre-cryopreservation was not deleterious (p > 0.05) for any analyzed variables. Addition of SP-SRF after cryopreservation was able to improve total and progressive motility (p < 0.05) when boar semen was cryopreserved without SP-SRF; however, it was not able to decrease tyrosine phosphorylation (p > 0.05) or improve IPIAH cells (p > 0.05). FR was not (p > 0.05) statistically increased by the addition of seminal plasma, though females inseminated with frozen-thawed boar semen plus SP-SRF did perform better than those inseminated with sperm lacking seminal plasma. Thus, we conclude that sperm fourfold stain can be used to simultaneously evaluate plasma and acrosomal membrane integrity and mitochondrial membrane potential, and the addition of SP-SRF at thawed boar semen cryopreserved in absence of SP-SRF improve its total and progressive motility. PMID:27529819

  2. Gas-chromatographic analyses of the subcaudal gland secretion of the European badger (Meles meles) part I: chemical differences related to individual parameters.

    PubMed

    Buesching, C D; Waterhouse, J S; Macdonald, D W

    2002-01-01

    In many species, chemical signals are important in the context of intraspecific communication. European badgers (Meles meles) use the secretion of their subcaudal gland to mark both the environment and conspecifics. In this paper, we investigated the chemical composition of subcaudal gland secretions and how it varies among individuals according to group membership, season, sex, age, body condition, and reproductive status. We analyzed 66 samples by gas chromatography using a mass-spectrometer as detector. We found 110 different components, of which 21 were present in every profile. The chemical composition of the secretions proved to be highly individual-specific, but no single peak was found to be typical for one of the investigated categories (season, sex, etc.). Analyses of the relative area (% area) that every peak contributed to the overall profile area showed that, in general, group members have more similar profiles than do badgers from different groups. Composition varied over seasons and between sexes and was influenced by age, body condition, and reproductive status. We, therefore, conclude that the secretion not only encodes group membership and individuality as previously assumed, but might also convey information about fitness-related parameters. PMID:11868678

  3. The effects of additives in napier grass silages on chemical composition, feed intake, nutrient digestibility and rumen fermentation.

    PubMed

    Bureenok, Smerjai; Yuangklang, Chalermpon; Vasupen, Kraisit; Schonewille, J Thomas; Kawamoto, Yasuhiro

    2012-09-01

    The effect of silage additives on ensiling characteristics and nutritive value of Napier grass (Pennisetum purpureum) silages was studied. Napier grass silages were made with no additive, fermented juice of epiphytic lactic acid bacteria (FJLB), molasses or cassava meal. The ensiling characteristics were determined by ensiling Napier grass silages in airtight plastic pouches for 2, 4, 7, 14, 21 and 45 d. The effect of Napier grass silages treated with these additives on voluntary feed intake, digestibility, rumen fermentation and microbial rumen fermentation was determined in 4 fistulated cows using 4×4 Latin square design. The pH value of the treated silages rapidly decreased, and reached to the lowest value within 7 d of the start of fermentation, as compared to the control. Lactic acid content of silages treated with FJLB was stable at 14 d of fermentation and constant until 45 d of ensiling. At 45 d of ensiling, neutral detergent fiber (NDF) and acid detergent fiber (ADF) of silage treated with cassava meal were significantly lower (p<0.05) than the others. In the feeding trial, the intake of silage increased (p<0.05) in the cow fed with the treated silage. Among the treatments, dry matter intake was the lowest in the silage treated with cassava meal. The organic matter, crude protein and NDF digestibility of the silage treated with molasses was higher than the silage without additive and the silage treated with FJLB. The rumen parameters: ruminal pH, ammonia-nitrogen (NH3-N), volatile fatty acid (VFA), blood urea nitrogen (BUN) and bacterial populations were not significantly different among the treatments. In conclusion, these studies confirmed that the applying of molasses improved fermentative quality, feed intake and digestibility of Napier grass.

  4. The effect of chemical additives on the synthesis of ethanol. Final technical report, September 15, 1987--March 15, 1992

    SciTech Connect

    Chuang, S.S.C.

    1992-03-06

    The objective of this research was to investigate the reaction mechanism of higher alcohol and aldehyde synthesis from syngas and the role of additives in the synthesis. An in situ IR reaction system and probe molecule technique were developed to study adsorbed species, active sites, and reaction pathway during reaction. The catalysts used for this study included silica-supported Rh, Ru, and Ni. (VC)

  5. Influence of dried Hokkaido pumpkin and ascorbic acid addition on chemical properties and colour of corn extrudates.

    PubMed

    Obradović, Valentina; Babić, Jurislav; Šubarić, Drago; Jozinović, Antun; Ačkar, Đurđica; Klarić, Ilija

    2015-09-15

    The influence of Hokkaido pumpkin powder (PP) addition to corn grits at levels 4%, 6%, and 8% and ascorbic acid (AA) addition at levels 0.5% and 1% was evaluated. Extrusion was done using a single-screw extruder at two temperature regimes: 135/170/170°C (E1) and 100/150/150°C (E2). Mathematical models that describe the influence of additives on the colour of extrudates were determined. Raw extrusion mixtures as well as obtained extrudates were tested for ascorbic acid, polyphenol, proteins, fat, crude fibre, ash and carotenoids content, and antioxidant activity. E1 extrusion regime acted favourably on polyphenols, crude fibre content, and antioxidant activity. It also caused higher fat degradation than E2 extrusion. Xanthophylls (lutein and zeaxanthin) were less sensitive to extrusion than carotenes (α-carotene, 9-cis-β-carotene and 13-cis-β-carotene). Ascorbic acid was more sensitive to higher extrusion temperatures (49-76% degradation). It provided protection to carotenoids and consequently the colour of the extrudates.

  6. Detection of the hydroperoxyl radical HO2 toward ρ Ophiuchi A. Additional constraints on the water chemical network

    NASA Astrophysics Data System (ADS)

    Parise, B.; Bergman, P.; Du, F.

    2012-05-01

    Context. Hydrogen peroxide (HOOH) was recently detected toward ρ Oph A. Subsequent astrochemical modeling that included reactions in the gas phase and on the surface of dust grains was able to explain the observed abundance, and highlighted the importance of grain chemistry in the formation of HOOH as an intermediate product in water formation. This study also predicted that the hydroperoxyl radical HO2, the precursor of HOOH, should be detectable. Aims: We aim at detecting the hydroperoxyl radical HO2 in ρ Oph A. Methods: We used the IRAM 30 m and the APEX telescopes to target the brightest HO2 lines at about 130 and 260 GHz. Results: We detect five lines of HO2 (comprising seven individual molecular transitions). The fractional abundance of HO2 is found to be about 10-10, a value similar to the abundance of HOOH. This observational result is consistent with the prediction of the above mentioned astrochemical model, and thereby validates our current understanding of the water formation on dust grains. Conclusions: This detection, anticipated by a sophisticated gas-grain chemical model, demonstrates that models of grain chemistry have improved tremendously and that grain surface reactions now form a crucial part of the overall astrochemical network. Based on observations carried out with the IRAM 30 m and the APEX telescopes. IRAM is supported by INSU/CNRS (France), MPG (Germany) and IGN (Spain). APEX is a collaboration between the Max Planck Institute for Radio Astronomy, the Onsala Space Observatory, and the European Southern Observatory.

  7. Effects of drying control chemical additive on properties of Li 4Ti 5O 12 negative powders prepared by spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Ju, Seo Hee; Kang, Yun Chan

    High-density Li 4Ti 5O 12 powders comprising spherical particles are prepared by spray pyrolysis from a solution containing dimethylacetamide (drying control chemical additive) and citric acid and ethylene glycol (organic additives). The prepared powders have high discharge capacities and good cycle properties. The optimum concentration of dimethylacetamide is 0.5 M. The addition of dimethylacetamide to the polymeric spray solutions containing citric acid and ethylene glycol helps in the effective control of the morphology of the Li 4Ti 5O 12 powders. At a constant current density of 0.17 mA g -1, the initial discharge capacities of the powders obtained from the spray solution with and without the organic additives are 171 and 167 mAh g -1, respectively.

  8. Implications of using approximate Bloch-McConnell equations in NMR analyses of chemically exchanging systems: application to the electron self-exchange of plastocyanin

    NASA Astrophysics Data System (ADS)

    Flemming Hansen, D.; Led, Jens J.

    2003-08-01

    The validity of a series of approximate solutions of the Bloch-McConnell equations normally applied in the analyses of chemically exchanging systems is evaluated, using the electron self-exchange (ESE) in the blue copper protein plastocyanin from Anabaena variabilis as an example. The evaluation is based on a comparison with the results of a complete analysis of the NMR signals of chemically exchanging nuclei that allows an independent and accurate determination of all the involved parameters. The complete analysis is based on the general solution of the Bloch-McConnell equations. It includes a simultaneous analysis of the chemical shift, and the transverse and longitudinal relaxation rates of the observed nuclei as well as the variation of these parameters with the molar fractions of the exchanging species and the rate of the chemical exchange process. The linear prediction model method was used in the data analysis to achieve the highest possible precision. Surprisingly, it is found that the fast exchange condition may not be fulfilled even in cases where a single exchange-averaged NMR signal is observed, and the Larmor frequency and relaxation rates depend linearly on the molar fractions of the exchanging species. In such cases the use of approximate solutions in the analysis of the transverse relaxation rates and the pseudo-contact shifts can lead to erroneous results. In limiting cases close to the fast exchange and slow exchange regimes correct values of some of the parameters can be obtained using the second order approximate solution of the Bloch-McConnell equations. In contrast, the complete analysis of the NMR signals results in an accurate determination of the exchange rates and the NMR parameters of the exchanging sites. This, in turn, can provide information about the structure and function of a protein undergoing chemically exchange. For the investigated plastocyanin the complete analysis results in an accurate determination of the paramagnetic

  9. Analysing spatio-temporal patterns of the global NO2-distribution retrieved from GOME satellite observations using a generalized additive model

    NASA Astrophysics Data System (ADS)

    Hayn, M.; Beirle, S.; Hamprecht, F. A.; Platt, U.; Menze, B. H.; Wagner, T.

    2009-04-01

    With the increasing availability of observations from different space-borne sensors, the joint analysis of observational data from multiple sources becomes more and more attractive. For such an analysis - oftentimes with little prior knowledge about local and global interactions between the different observational variables available - an explorative data-driven analysis of the remote sensing data may be of particular relevance. In the present work we used generalized additive models (GAM) in this task, in an exemplary study of spatio-temporal patterns in the tropospheric NO2-distribution derived from GOME satellite observations (1996 to 2001) at global scale. We modelled different temporal trends in the time series of the observed NO2, but focused on identifying correlations between NO2 and local wind fields. Here, our nonparametric modelling approach had several advantages over standard parametric models: While the model-based analysis allowed to test predefined hypotheses (assuming, for example, sinusoidal seasonal trends) only, the GAM allowed to learn functional relations between different observational variables directly from the data. This was of particular interest in the present task, as little was known about relations between the observed NO2 distribution and transport processes by local wind fields, and the formulation of general functional relationships to be tested remained difficult. We found the observed temporal trends - weekly, seasonal and linear changes - to be in overall good agreement with previous studies and alternative ways of data analysis. However, NO2 observations showed to be affected by wind-dominated processes over several areas, world wide. Here we were able to estimate the extent of areas affected by specific NO2 emission sources, and to highlight likely atmospheric transport pathways. Overall, using a nonparametric model provided favourable means for a rapid inspection of this large spatio-temporal data set,with less bias than

  10. Chemical additive to enhance antimicrobial efficacy of chlorine and control cross-contamination during immersion chill of broiler carcasses.

    PubMed

    Schambach, B T; Berrang, M E; Harrison, M A; Meinersmann, R J

    2014-09-01

    Immersion chilling of broiler carcasses can be a site for cross-contamination between the occasional highly contaminated carcass and those that are co-chilled. Chlorine is often used as an antimicrobial but can be overcome by organic material. A proprietary chlorine stabilizer (T-128) based on phosphoric acid-propylene glycol was tested as a chill tank additive in experiments simulating commercial broiler chilling. In bench-scale experiments, 0.5% T-128 was compared with plain water (control), 50 ppm of chlorine, and the combination of 0.5% T-128 with 50 ppm of chlorine to control transfer of Salmonella and Campylobacter from inoculated wing drummettes to co-chilled uninoculated drummettes. Both chlorine and T-128 lessened cross-contamination with Salmonella (P < 0.05); T-128 and T-128 with chlorine were significantly more effective (P < 0.05) than the control or plain chlorine for control of Campylobacter. T-128 treatments were noted to have a pH of less than 4.0; an additional experiment demonstrated that the antimicrobial effect of T-128 was not due merely to a lower pH. In commercial broiler chilling, a pH close to 6.0 is preferred to maximize chlorine effectiveness, while maintaining water-holding capacity of the meat. In a set of pilot-scale experiments with T-128, a near-ideal pH of 6.3 was achieved by using tap water instead of the distilled water used in bench-scale experiments. Pilot-scale chill tanks were used to compare the combination of 0.5% T-128 and 50 ppm of chlorine with 50 ppm of plain chlorine for control of cross-contamination between whole carcasses inoculated with Salmonella and Campylobacter and co-chilled uninoculated carcasses. The T-128 treatment resulted in significantly less crosscontamination by either direct contact or water transfer with both organisms compared with plain chlorine treatment. T-128 may have use in commercial broiler processing to enhance the effectiveness of chlorine in processing water. PMID:25198851

  11. Chemical additive to enhance antimicrobial efficacy of chlorine and control cross-contamination during immersion chill of broiler carcasses.

    PubMed

    Schambach, B T; Berrang, M E; Harrison, M A; Meinersmann, R J

    2014-09-01

    Immersion chilling of broiler carcasses can be a site for cross-contamination between the occasional highly contaminated carcass and those that are co-chilled. Chlorine is often used as an antimicrobial but can be overcome by organic material. A proprietary chlorine stabilizer (T-128) based on phosphoric acid-propylene glycol was tested as a chill tank additive in experiments simulating commercial broiler chilling. In bench-scale experiments, 0.5% T-128 was compared with plain water (control), 50 ppm of chlorine, and the combination of 0.5% T-128 with 50 ppm of chlorine to control transfer of Salmonella and Campylobacter from inoculated wing drummettes to co-chilled uninoculated drummettes. Both chlorine and T-128 lessened cross-contamination with Salmonella (P < 0.05); T-128 and T-128 with chlorine were significantly more effective (P < 0.05) than the control or plain chlorine for control of Campylobacter. T-128 treatments were noted to have a pH of less than 4.0; an additional experiment demonstrated that the antimicrobial effect of T-128 was not due merely to a lower pH. In commercial broiler chilling, a pH close to 6.0 is preferred to maximize chlorine effectiveness, while maintaining water-holding capacity of the meat. In a set of pilot-scale experiments with T-128, a near-ideal pH of 6.3 was achieved by using tap water instead of the distilled water used in bench-scale experiments. Pilot-scale chill tanks were used to compare the combination of 0.5% T-128 and 50 ppm of chlorine with 50 ppm of plain chlorine for control of cross-contamination between whole carcasses inoculated with Salmonella and Campylobacter and co-chilled uninoculated carcasses. The T-128 treatment resulted in significantly less crosscontamination by either direct contact or water transfer with both organisms compared with plain chlorine treatment. T-128 may have use in commercial broiler processing to enhance the effectiveness of chlorine in processing water.

  12. Physico-chemical and microbiological analyses of fermented corn cob, rice bran and cowpea husk for use in composite rabbit feed.

    PubMed

    Oduguwa, Oluseyi O; Edema, Mojisola O; Ayeni, Ayodeji O

    2008-04-01

    An experiment was conducted to evaluate the effect of fermentation on the proximate composition of corn cob, rice bran and cowpea husk for use in composite rabbit feed formulations. The test ingredients were moistened with tap water and allowed to ferment naturally at room temperature. During fermentation, samples of the fermenting materials were extracted at zero, 24 and 48 h for physico-chemical and microbiological analyses using standard procedures. The microorganisms associated with the fermenting materials were identified as Rhizopus oligosporus, Aspergillus oryzae, Aspergillus niger, Rhodotorula, Geotrichum candidum, Candida albicans, and Saccharomyces cerevisiae. Two (R. oligosporus and S. cerevisiae) out of microorganisms present were used as starter cultures to ferment the test ingredients and the fermented products were then analyzed. From the results obtained S. cerevisiae enhanced the protein and fat contents while R. oligosporus was able to degrade the fiber significantly. PMID:17502134

  13. Responses of secondary chemicals in sugar maple (Acer saccharum) seedlings to UV-B, springtime warming and nitrogen additions.

    PubMed

    Sager, E P S; Hutchinson, T C

    2006-10-01

    Anticipated effects of climate change involve complex interactions in the field. To assess the effects of springtime warming, ambient ultraviolet-B radiation (UV-B) and nitrogen fertilization on the foliar chemistry and herbivore activity of native sugar maple (Acer saccharum Marsh.) seedlings, we carried out a field experiment for 2 years at two sugar maple forests growing on soils of contrasting acidity. At the Oliver site, soils are derived from a strongly calcareous till, whereas the naturally acidic soils and base-poor soils of the Haliburton site are derived from the largely granitic Precambrian Shield. At both sites, removal of ambient UV-B led to increases in chlorogenic acid and some flavonoids and reduced herbivore activity. At Haliburton, ammonium nitrate fertilization led to further increases in foliar manganese (Mn), whereas at Oliver there were no such changes. Nitrogen additions led to decreases in the concentrations of some flavonoids at both sites, but seedlings at Oliver had significantly higher concentrations of flavonoids and chlorogenic acid than seedlings at Haliburton. We suggest that this could be associated with increased mobilization of Mn due to increased soil acidity, which interferes with the role of calcium (Ca) in the phenolic biosynthetic pathway. It appears that the composition of the forest soil governs the response of seedlings when they are exposed to abiotic stressors.

  14. ¹H and (15)N NMR Analyses on Heparin, Heparan Sulfates and Related Monosaccharides Concerning the Chemical Exchange Regime of the N-Sulfo-Glucosamine Sulfamate Proton.

    PubMed

    Pomin, Vitor H

    2016-09-07

    Heparin and heparan sulfate are structurally related glycosaminoglycans (GAGs). Both GAGs present, although in different concentrations, N-sulfo-glucosamine (GlcNS) as one of their various composing units. The conditional fast exchange property of the GlcNS sulfamate proton in these GAGs has been pointed as the main barrier to its signal detection via NMR experiments, especially ¹H-(15)N HSQC. Here, a series of NMR spectra is collected on heparin, heparan sulfate and related monosaccharides. The N-acetyl glucosamine-linked uronic acid types of these GAGs were properly assigned in the ¹H-(15)N HSQC spectra. Dynamic nuclear polarization (DNP) was employed in order to facilitate 1D spectral acquisition of the sulfamate (15)N signal of free GlcNS. Analyses on the multiplet pattern of scalar couplings of GlcNS (15)N has helped to understand the chemical properties of the sulfamate proton in solution. The singlet peak observed for GlcNS happens due to fast chemical exchange of the GlcNS sulfamate proton in solution. Analyses on kinetics of alpha-beta anomeric mutarotation via ¹H NMR spectra have been performed in GlcNS as well as other glucose-based monosaccharides. 1D ¹H and 2D ¹H-(15)N HSQC spectra recorded at low temperature for free GlcNS dissolved in a proton-rich solution showed signals from all exchangeable protons, including those belonging to the sulfamate group. This work suits well to the current grand celebration of one-century-anniversary of the discovery of heparin.

  15. ¹H and (15)N NMR Analyses on Heparin, Heparan Sulfates and Related Monosaccharides Concerning the Chemical Exchange Regime of the N-Sulfo-Glucosamine Sulfamate Proton.

    PubMed

    Pomin, Vitor H

    2016-01-01

    Heparin and heparan sulfate are structurally related glycosaminoglycans (GAGs). Both GAGs present, although in different concentrations, N-sulfo-glucosamine (GlcNS) as one of their various composing units. The conditional fast exchange property of the GlcNS sulfamate proton in these GAGs has been pointed as the main barrier to its signal detection via NMR experiments, especially ¹H-(15)N HSQC. Here, a series of NMR spectra is collected on heparin, heparan sulfate and related monosaccharides. The N-acetyl glucosamine-linked uronic acid types of these GAGs were properly assigned in the ¹H-(15)N HSQC spectra. Dynamic nuclear polarization (DNP) was employed in order to facilitate 1D spectral acquisition of the sulfamate (15)N signal of free GlcNS. Analyses on the multiplet pattern of scalar couplings of GlcNS (15)N has helped to understand the chemical properties of the sulfamate proton in solution. The singlet peak observed for GlcNS happens due to fast chemical exchange of the GlcNS sulfamate proton in solution. Analyses on kinetics of alpha-beta anomeric mutarotation via ¹H NMR spectra have been performed in GlcNS as well as other glucose-based monosaccharides. 1D ¹H and 2D ¹H-(15)N HSQC spectra recorded at low temperature for free GlcNS dissolved in a proton-rich solution showed signals from all exchangeable protons, including those belonging to the sulfamate group. This work suits well to the current grand celebration of one-century-anniversary of the discovery of heparin. PMID:27618066

  16. 1H and 15N NMR Analyses on Heparin, Heparan Sulfates and Related Monosaccharides Concerning the Chemical Exchange Regime of the N-Sulfo-Glucosamine Sulfamate Proton

    PubMed Central

    Pomin, Vitor H.

    2016-01-01

    Heparin and heparan sulfate are structurally related glycosaminoglycans (GAGs). Both GAGs present, although in different concentrations, N-sulfo-glucosamine (GlcNS) as one of their various composing units. The conditional fast exchange property of the GlcNS sulfamate proton in these GAGs has been pointed as the main barrier to its signal detection via NMR experiments, especially 1H-15N HSQC. Here, a series of NMR spectra is collected on heparin, heparan sulfate and related monosaccharides. The N-acetyl glucosamine-linked uronic acid types of these GAGs were properly assigned in the 1H-15N HSQC spectra. Dynamic nuclear polarization (DNP) was employed in order to facilitate 1D spectral acquisition of the sulfamate 15N signal of free GlcNS. Analyses on the multiplet pattern of scalar couplings of GlcNS 15N has helped to understand the chemical properties of the sulfamate proton in solution. The singlet peak observed for GlcNS happens due to fast chemical exchange of the GlcNS sulfamate proton in solution. Analyses on kinetics of alpha-beta anomeric mutarotation via 1H NMR spectra have been performed in GlcNS as well as other glucose-based monosaccharides. 1D 1H and 2D 1H-15N HSQC spectra recorded at low temperature for free GlcNS dissolved in a proton-rich solution showed signals from all exchangeable protons, including those belonging to the sulfamate group. This work suits well to the current grand celebration of one-century-anniversary of the discovery of heparin. PMID:27618066

  17. Results of mineral, chemical, and sulfate isotopic analyses of water, soil, rocks, and soil extracts from the Pariette Draw Watershed, Uinta Basin, Utah

    USGS Publications Warehouse

    Morrison, Jean M.; Tuttle, Michele L.W.; Fahy, Juli W.

    2015-08-06

    The goal of this study was to establish a process-based understanding of salt, Se, and B behavior to address whether these contaminants can be better managed, or if uncontrollable natural processes will overwhelm any attempts to bring Pariette Draw into compliance with respect to recently established total maximum daily limits (TMDLs). We collected data to refine our knowledge about the role of rock weathering and soil formation in the transport and storage of salt in the watershed and to show how salt is cycled under irrigated and natural conditions. Our approach was to sample rock, soils, and sediment on irrigated and natural terrain for mineralogical analysis to determine the residence of salt and associated Se and B, classify minerals as primary (related to rock formation) or secondary weathering products, and characterize mineral dissolution kinetics. Mineral and chemical analyses and selective extractions of rocks and soils provide useful information in understanding solute movement and mineral dissolution/ formation. The resulting data are critical in determining residence of salt, Se, and B in weathered rock and soil and understanding the mobility during water-rock-soil interactions. This report summarizes our methods for sample and data collection and tabulates the mineral, chemical, and isotopic data collected.

  18. Effect of addition of nano-hydroxyapatite on physico-chemical and antibiofilm properties of calcium silicate cements

    PubMed Central

    GUERREIRO-TANOMARU, Juliane Maria; VÁZQUEZ-GARCÍA, Fernando Antonio; BOSSO-MARTELO, Roberta; BERNARDI, Maria Inês Basso; FARIA, Gisele; TANOMARU, Mario

    2016-01-01

    ABSTRACT Objective Mineral Trioxide Aggregate (MTA) is a calcium silicate cement composed of Portland cement (PC) and bismuth oxide. Hydroxyapatite has been incorporated to enhance mechanical and biological properties of dental materials. This study evaluated physicochemical and mechanical properties and antibiofilm activity of MTA and PC associated with zirconium oxide (ZrO2) and hydroxyapatite nanoparticles (HAn). Material and Methods White MTA (Angelus, Brazil); PC (70%)+ZrO2 (30%); PC (60%)+ZrO2 (30%)+HAn (10%); PC (50%)+ZrO2 (30%)+HAn (20%) were evaluated. The pH was assessed by a digital pH-meter and solubility by mass loss. Setting time was evaluated by using Gilmore needles. Compressive strength was analyzed by mechanical test. Samples were radiographed alongside an aluminum step wedge to evaluate radiopacity. For the antibiofilm evaluation, materials were placed in direct contact with E. faecalis biofilm induced on dentine blocks. The number of colony-forming units (CFU mL-1) in the remaining biolfilm was evaluated. The results were submitted to ANOVA and the Tukey test, with 5% significance. Results There was no difference in pH levels of PC+ZrO2, PC+ZrO2+HAn (10%) and PC+ZrO2+HAn (20%) (p>0.05) and these cements presented higher pH levels than MTA (p<0.05). The highest solubility was observed in PC+ZrO2+HAn (10%) and PC+ZrO2+HAn (20%) (p<0.05). MTA had the shortest initial setting time (p<0.05). All the materials showed radiopacity higher than 3 mmAl. PC+ZrO2 and MTA had the highest compressive strength (p<0.05). Materials did not completely neutralize the bacterial biofilm, but the association with HAn provided greater bacterial reduction than MTA and PC+ZrO2 (p<0.05) after the post-manipulation period of 2 days. Conclusions The addition of HAn to PC associated with ZrO2 harmed the compressive strength and solubility. On the other hand, HAn did not change the pH and the initial setting time, but improved the radiopacity (HAn 10%), the final setting time

  19. Results of chemical and isotopic analyses of sediment and water from alluvium of the Canadian River near a closed municipal landfill, Norman, Oklahoma

    USGS Publications Warehouse

    Breit, George N.; Tuttle, Michele L.W.; Cozzarelli, Isabelle M.; Christenson, Scott C.; Jaeschke, Jeanne B.; Fey, David L.; Berry, Cyrus J.

    2005-01-01

    Results of physical and chemical analyses of sediment and water collected near a closed municipal landfill at Norman, Oklahoma are presented in this report. Sediment analyses are from 40 samples obtained by freeze-shoe coring at 5 sites, and 14 shallow (depth <1.3 m) sediment samples. The sediment was analyzed to determine grain size, the abundance of extractable iron species and the abundances and isotopic compositions of forms of sulfur. Water samples included pore water from the freeze-shoe core, ground water, and surface water. Pore water from 23 intervals of the core was collected and analyzed for major and trace dissolved species. Thirteen ground-water samples obtained from wells within a few meters of the freeze-shoe core sites and one from the landfill were analyzed for major and trace elements as well as the sulfur and oxygen isotope composition of dissolved sulfate. Samples of surface water were collected at 10 sites along the Canadian River from New Mexico to central Oklahoma. These river-water samples were analyzed for major elements, trace elements, and the isotopic composition of dissolved sulfate.

  20. C4F8O/O2/N-based Additive Gases for Silicon Nitride Plasma Enhanced Chemical Vapor Deposition Chamber Cleaning with Low Global Warming Potentials

    NASA Astrophysics Data System (ADS)

    Kim, Ji Hwang; Bae, Jeong Woon; Oh, Chang Hyun; Kim, Ki Joon; Lee, Nae Eung; Yeom, Geun Young

    2002-11-01

    In this study, N2O and NO were added as additive gases to C4F8O/O2 for plasma enhanced chemical vapor deposition (PECVD) silicon nitride chamber cleaning and their effects on the emission properties of perfluorocarbon compounds (PFCs) were investigated. The cleaning rate, destruction and removal efficiencies (DREs), and million metric tons of carbon equivalent (MMTCE) were studied as a function of flow rates of PFCs and additive gases. The use of C4F8O/O2 alone showed the highest cleaning rate and the lowest emission properties at the cleaning condition of 20%C4F8O/80%O2, working pressure of 500 mTorr, and 13.56 MHz rf power of 350 W. By the addition of about 20% NO or 20% N2O to the optimized C4F8O/O2, the additional reduction of MMTCE higher than 50% could be obtained. The addition of NO resulted in lower MMTCE compared to that in the case of the addition of N2O mostly due to the higher silicon nitride cleaning rate in the latter case.

  1. Chemicals of emerging concern in water and bottom sediment in Great Lakes areas of concern, 2010 to 2011-Collection methods, analyses methods, quality assurance, and data

    USGS Publications Warehouse

    Lee, Kathy E.; Langer, Susan K.; Menheer, Michael A.; Foreman, William T.; Furlong, Edward T.; Smith, Steven G.

    2012-01-01

    The U.S. Geological Survey (USGS) cooperated with the U.S. Environmental Protection Agency and the U.S. Fish and Wildlife Service on a study to identify the occurrence of chemicals of emerging concern (CECs) in water and bottom-sediment samples collected during 2010–11 at sites in seven areas of concern (AOCs) throughout the Great Lakes. Study sites include tributaries to the Great Lakes in AOCs located near Duluth, Minn.; Green Bay, Wis.; Roches­ter, N.Y.; Detroit, Mich.; Toledo, Ohio; Milwaukee, Wis.; and Ashtabula, Ohio. This report documents the collection meth­ods, analyses methods, quality-assurance data and analyses, and provides the data for this study. Water and bottom-sediment samples were analyzed at the USGS National Water Quality Laboratory in Denver, Colo., for a broad suite of CECs. During this study, 135 environmental and 23 field dupli­cate samples of surface water and wastewater effluent, 10 field blank water samples, and 11 field spike water samples were collected and analyzed. Sixty-one of the 69 wastewater indicator chemicals (laboratory method 4433) analyzed were detected at concentrations ranging from 0.002 to 11.2 micrograms per liter. Twenty-eight of the 48 pharmaceuticals (research method 8244) analyzed were detected at concentrations ranging from 0.0029 to 22.0 micro­grams per liter. Ten of the 20 steroid hormones and sterols analyzed (research method 4434) were detected at concentrations ranging from 0.16 to 10,000 nanograms per liter. During this study, 75 environmental, 13 field duplicate samples, and 9 field spike samples of bottom sediment were collected and analyzed for a wide variety of CECs. Forty-seven of the 57 wastewater indicator chemicals (laboratory method 5433) analyzed were detected at concentrations ranging from 0.921 to 25,800 nanograms per gram. Seventeen of the 20 steroid hormones and sterols (research method 6434) analyzed were detected at concentrations ranging from 0.006 to 8,921 nanograms per gram. Twelve of

  2. The family of ferrocene-stabilized silylium ions: synthesis, 29Si NMR characterization, Lewis acidity, substituent scrambling, and quantum-chemical analyses.

    PubMed

    Müther, Kristine; Hrobárik, Peter; Hrobáriková, Veronika; Kaupp, Martin; Oestreich, Martin

    2013-12-01

    The purpose of this systematic experimental and theoretical study is to deeply understand the unique bonding situation in ferrocene-stabilized silylium ions as a function of the substituents at the silicon atom and to learn about the structure parameters that determine the (29)Si NMR chemical shift and electrophilicity of these strong Lewis acids. For this, ten new members of the family of ferrocene-stabilized silicon cations were prepared by a hydride abstraction reaction from silanes with the trityl cation and characterized by multinuclear (1)H and (29)Si NMR spectroscopy. A closer look at the NMR spectra revealed that additional minor sets of signals were not impurities but silylium ions with substitution patterns different from that of the initially formed cation. Careful assignment of these signals furnished experimental proof that sterically less hindered silylium ions are capable of exchanging substituents with unreacted silane precursors. Density functional theory calculations provided mechanistic insight into that substituent transfer in which the migrating group is exchanged between two silicon fragments in a concerted process involving a ferrocene-bridged intermediate. Moreover, the quantum-chemical analysis of the (29)Si NMR chemical shifts revealed a linear relationship between δ((29)Si) values and the Fe···Si distance for subsets of silicon cations. An electron localization function and electron localizability indicator analysis shows a three-center two-electron bonding attractor between the iron, silicon, and C'(ipso) atoms, clearly distinguishing the silicon cations from the corresponding carbenium ions and boranes. Correlations between (29)Si NMR chemical shifts and Lewis acidity, evaluated in terms of fluoride ion affinities, are seen only for subsets of silylium ions, sometimes with non-intuitive trends, indicating a complicated interplay of steric and electronic effects on the degree of the Fe···Si interaction.

  3. Effect of additive gases and injection methods on chemical dry etching of silicon nitride, silicon oxynitride, and silicon oxide layers in F{sub 2} remote plasmas

    SciTech Connect

    Yun, Y. B.; Park, S. M.; Kim, D. J.; Lee, N.-E.; Kim, K. S.; Bae, G. H.

    2007-07-15

    The authors investigated the effects of various additive gases and different injection methods on the chemical dry etching of silicon nitride, silicon oxynitride, and silicon oxide layers in F{sub 2} remote plasmas. N{sub 2} and N{sub 2}+O{sub 2} gases in the F{sub 2}/Ar/N{sub 2} and F{sub 2}/Ar/N{sub 2}/O{sub 2} remote plasmas effectively increased the etch rate of the layers. The addition of direct-injected NO gas increased the etch rates most significantly. NO radicals generated by the addition of N{sub 2} and N{sub 2}+O{sub 2} or direct-injected NO molecules contributed to the effective removal of nitrogen and oxygen in the silicon nitride and oxide layers, by forming N{sub 2}O and NO{sub 2} by-products, respectively, and thereby enhancing SiF{sub 4} formation. As a result of the effective removal of the oxygen, nitrogen, and silicon atoms in the layers, the chemical dry etch rates were enhanced significantly. The process regime for the etch rate enhancement of the layers was extended at elevated temperature.

  4. Superhydrophobic powder additives to enhance chemical agent resistant coating systems for military equipment for the U.S. Marine Corps (USMC) Corrosion Prevention and Control (CPAC) Program

    SciTech Connect

    Pawel, Steven J.; Armstrong, Beth L.; Haynes, James A.

    2015-07-01

    The primary goal of the CPAC program at ORNL was to explore the feasibility of introducing various silica-based superhydrophobic (SH) powder additives as a way to improve the corrosion resistance of US Department of Defense (DOD) military-grade chemical agent resistant coating (CARC) systems. ORNL had previously developed and patented several SH technologies of interest to the USMC, and one of the objectives of this program was to identify methods to incorporate these technologies into the USMC’s corrosion-resistance strategy. This report discusses findings of the CPAC and their application.

  5. Effects of N{sub 2}O gas addition on the properties of ZnO films grown by catalytic reaction-assisted chemical vapor deposition

    SciTech Connect

    Yasui, Kanji Morioka, Makoto; Kanauchi, Shingo; Ohashi, Yuki; Kato, Takahiro; Tamayama, Yasuhiro

    2015-11-15

    The influence of N{sub 2}O gas addition on the properties of zinc oxide (ZnO) films grown on a-plane (11–20) sapphire (a-Al{sub 2}O{sub 3}) substrates was investigated, using a chemical vapor deposition method based on the reaction between dimethylzinc and high-temperature H{sub 2}O produced by a catalytic H{sub 2}-O{sub 2} reaction on platinum (Pt) nanoparticles. The addition of N{sub 2}O was found to increase the size of the crystalline facets and to improve the crystal orientation along the c-axis. The electron mobility at 290 K was also increased to 234 cm{sup 2}/Vs following the addition of N{sub 2}O gas at a pressure of 3.2 × 10{sup −3 }Pa. In addition, the minimum full width at half maximum of the most intense photoluminescence peak derived from neutral donor bound excitons at 10 K decreased to 0.6 meV by the addition of N{sub 2}O gas at a pressure of 3.1 × 10{sup −2 }Pa.

  6. [Effects of understory removal and nitrogen addition on the soil chemical and biological properties of Pinus sylvestris var. mongolica plantation in Keerqin Sandy Land].

    PubMed

    Lin, Gui-Gang; Zhao, Qiong; Zhao, Lei; Li, Hui-Chao; Zeng, De-Hui

    2012-05-01

    A full factorial experiment was conducted to study the effects of understory removal and nitrogen addition (8 g x m(-2)) on the soil NO(3-)-N and NH(4+)-N concentrations, potential net nitrogen mineralization rate (PNM) and nitrification rate (PNN), microbial biomass C (MBC) and N (MBN), MBC/MBN, urease and acid phosphomonoesterase activities, and Olsen-P concentration in a Pinus sylvestris var. mongolica plantation in Keerqin Sandy Land during a growth season. Understory removal decreased the soil NH(4+)-N concentration, PNM, MBC, and MBN/MBN significantly, increased the soil Olsen-P concentration, but had little effects on the soil NO(3-)-N concentration, PNN, and urease and acid phosphomonoesterase activities. Nitrogen addition increased the soil NO(3-)-N concentration, PNM and PNN significantly, but had little effects on the other test properties. The interaction between understory removal and nitrogen addition had significant effects on the soil NH(4+)-N concentration, but little effects on the soil NO(3-)-N concentration. However, the soil NO(3-)-N concentration in the plots of understory removal with nitrogen addition was increased by 27%, compared with the plots of nitrogen addition alone, which might lead to the leaching of NO3-. It was suggested that understory vegetation could play an important role in affecting the soil chemical and biological properties in Mongolian pine plantations, and hence, the importance of understory vegetation should not be neglected when the forest management and restoration were implemented. PMID:22919826

  7. Studies on nano-additive for the substitution of hazardous chemical substances in antifouling coatings for the protection of ship hulls.

    PubMed

    Zhao, Xiaodong; Fan, Weijie; Duan, Jizhou; Hou, Baorong

    2014-07-01

    Adhesion and growth of biofouling organisms have severe influence on the reliability, service life and environmental adaptability of marine ships. Based on the bactericidal capacity of cuprous oxide and photochemical effect of nano-additive, environment-friendly and efficient marine antifouling paints were prepared in this study. The evaluation of the antifouling paints was carried out by the laboratory method using bacteria and phytoplanktonic microorganisms as target organisms, as well as measurements with panels in shallow submergence in natural seawater. Results showed good agreement of all the tests, indicating the remarkable antifouling performance of the paints. To our knowledge, this was one of the first systematic studies on effects of nano-additive for the substitution of hazardous chemical substances in antifouling coatings for the protection of ship hulls by measurements on bacterial inhibition, algal adhesion and growth of large organisms. PMID:25016277

  8. The effect of terebinth (Pistacia terebinthus L.) coffee addition on the chemical and physical characteristics, colour values, organic acid profiles, mineral compositions and sensory properties of ice creams.

    PubMed

    Yüksel, Arzu Kavaz; Şat, Ihsan Güngör; Yüksel, Mehmet

    2015-12-01

    The aim of this research was to evaluate the effect of terebinth (Pistacia terebinthus L.) coffee addition (0.5, 1 and 2 %) on the chemical and physical properties, colour values, organic acid profiles, mineral contents and sensory characteristics of ice creams. The total solids, fat, titratable acidity, viscosity, first dripping time and complete melting time values, a (*) and b (*) colour properties, citric, lactic, acetic and butyric acid levels and Ca, Cu, Mg, Fe, K, Zn and Na concentrations of ice creams showed an increase with the increment of terebinth coffee amount, while protein, pH, L (*), propionic acid and orotic acid values decreased. However, Al and malic acid were not detected in any of the samples. The overall acceptability scores of the sensory properties showed that the addition of 1 % terebinth coffee to the ice cream was more appreciated by the panellists.

  9. The effect of terebinth (Pistacia terebinthus L.) coffee addition on the chemical and physical characteristics, colour values, organic acid profiles, mineral compositions and sensory properties of ice creams.

    PubMed

    Yüksel, Arzu Kavaz; Şat, Ihsan Güngör; Yüksel, Mehmet

    2015-12-01

    The aim of this research was to evaluate the effect of terebinth (Pistacia terebinthus L.) coffee addition (0.5, 1 and 2 %) on the chemical and physical properties, colour values, organic acid profiles, mineral contents and sensory characteristics of ice creams. The total solids, fat, titratable acidity, viscosity, first dripping time and complete melting time values, a (*) and b (*) colour properties, citric, lactic, acetic and butyric acid levels and Ca, Cu, Mg, Fe, K, Zn and Na concentrations of ice creams showed an increase with the increment of terebinth coffee amount, while protein, pH, L (*), propionic acid and orotic acid values decreased. However, Al and malic acid were not detected in any of the samples. The overall acceptability scores of the sensory properties showed that the addition of 1 % terebinth coffee to the ice cream was more appreciated by the panellists. PMID:26604374

  10. Studies on nano-additive for the substitution of hazardous chemical substances in antifouling coatings for the protection of ship hulls.

    PubMed

    Zhao, Xiaodong; Fan, Weijie; Duan, Jizhou; Hou, Baorong

    2014-07-01

    Adhesion and growth of biofouling organisms have severe influence on the reliability, service life and environmental adaptability of marine ships. Based on the bactericidal capacity of cuprous oxide and photochemical effect of nano-additive, environment-friendly and efficient marine antifouling paints were prepared in this study. The evaluation of the antifouling paints was carried out by the laboratory method using bacteria and phytoplanktonic microorganisms as target organisms, as well as measurements with panels in shallow submergence in natural seawater. Results showed good agreement of all the tests, indicating the remarkable antifouling performance of the paints. To our knowledge, this was one of the first systematic studies on effects of nano-additive for the substitution of hazardous chemical substances in antifouling coatings for the protection of ship hulls by measurements on bacterial inhibition, algal adhesion and growth of large organisms.

  11. High-sensitivity matrix-assisted laser desorption/ionization Fourier transform mass spectrometry analyses of small carbohydrates and amino acids using oxidized carbon nanotubes prepared by chemical vapor deposition as matrix.

    PubMed

    Wang, Cui-hong; Li, Jian; Yao, Sheng-jun; Guo, Yin-long; Xia, Xing-hua

    2007-12-01

    In matrix-assisted laser desorption/ionization (MALDI) Fourier transform mass spectrometry (FTMS) analyses of small oligosaccharides and amino acids, high sensitivities for oligosaccharides (10 fmol) were obtained by introducing oxidized carbon nanotubes (CNTs) with short and open-end structure as valuable matrix. The CNTs were deposited in porous anodic alumina (PAA) templates by chemical vapor deposition. Transmission electron microscopy (TEM) images show that those CNTs include low levels of amorphous carbon. Thus, the background interference signals generally caused by amorphous carbon powder in CNTs can be reduced effectively. Experiments also confirmed that the FTMS signal intensity of CNTs prepared in PAA template is much lower than that of commercial multi-wall carbon nanotubes (MCNTs). Moreover, the purified process for CNTs with mixed acid (H2SO4 and HNO3) also contributed to the minimization of background. Intense signals corresponding to alkali cation adduct of neutral carbohydrates and amino acids have been acquired. In addition, reliable quantitative analyses for urine and corn root were also achieved successfully. The present work will open a new way to the application of oxidized CNTs as an effective matrix in MALDI MS research.

  12. Evaluation of impact factors on PM2.5 based on long-term chemical components analyses in the megacity Beijing, China.

    PubMed

    Chen, Yuan; Schleicher, Nina; Cen, Kuang; Liu, Xiuli; Yu, Yang; Zibat, Volker; Dietze, Volker; Fricker, Mathieu; Kaminski, Uwe; Chen, Yizhen; Chai, Fahe; Norra, Stefan

    2016-07-01

    Nine years of sampling and analyses of fine particles (PM2.5) were performed in Beijing from 2005 to 2013. Twenty-seven chemical elements and black carbon (BC) in PM2.5 were analyzed in order to study chemical characteristics and temporal distribution of Beijing aerosols. Principle component analysis defined different types of elemental sources, based on which, the influences of a variety of anthropogenic activities including governmental intervention measures and natural sources on air quality were evaluated. For the first time, Ga is used as a tracer element for heating activities mainly using coal in Beijing, due to its correlation with BC and coal combustion, as well as its concentration variation between the heating- and non-heating periods. The traffic restrictions effectively reduced emissions of relevant heavy metals such as As, Cd, Sn and Sb. The expected long-term effectiveness of the steel smelters relocation was not observed due to the nearby relocation with increased capacity. Firework display during every Chinese spring festival season and special events such as the Olympic Games resulted in several times higher concentrations of K, Sr and Ba than other days and thus they were proposed as tracers for firework display. The impacts of all these factors were quantified and evaluated. Sand dust or dust storms induced higher concentrations of geogenic elements in PM2.5 compared to non-dust days. Sustainable mitigation measures, such as traffic restrictions, are necessary to be continued and improved to obtain more "blue sky" days in the future.

  13. Rates of water exsolution and magma ascent inferred from microstructures and chemical analyses of the Tokachi-Ishizawa obsidian lava, Shirataki, northern Hokkaido, Japan

    NASA Astrophysics Data System (ADS)

    Sano, Kyohei; Wada, Keiji; Sato, Eiichi

    2015-02-01

    Very few quantitative textural data exist for viscous obsidian lava eruptions, and it is still unclear from the mechanical behavior of ascending magmas if outgassing is controlled dominantly by brittle or ductile deformation. In order to obtain insights into how degassing and ascent proceed in such highly viscous magmas, we conducted textural and chemical analyses of the Tokachi-Ishizawa (TI) obsidian lava, in the Shirataki rhyolite volcanic area, northern Hokkaido, Japan, and estimated the water exsolution rate and ascent rate. The storage conditions of the TI lava are estimated from the Rhyolite-MELTS program as T = 840-860 °C and P = 50 MPa using the mineral assemblages and the chemical compositions of plagioclase phenocrysts and glass. To estimate the magma ascent rate, we measured the length, width, and number of oxide microlites using three-dimensional techniques. Textural analysis indicates that the microlite number densities (Nv [number/m3]) of oxide microlites in TI lava samples are 2.1 × 1013 to 1.4 × 1014, which correspond to water exsolution rates of 3.5 × 10- 9 to 1.7 × 10- 8 wt.%/s and ascent rates of 1.7 × 10- 6 to 1.1 × 10- 5 m/s. Together with an estimate of viscosity, the inferred ascent velocities allow us to examine the mechanical behavior of the magma in the conduit. We conclude that the development of permeability leading to outgassing is controlled by ductile deformation rather than brittle fracturing.

  14. Chemical dissolution-front instability associated with water-rock reactions in groundwater hydrology: Analyses of porosity-permeability relationship effects

    NASA Astrophysics Data System (ADS)

    Zhao, Chongbin; Hobbs, B. E.; Ord, A.

    2016-09-01

    Because dissolution of rocks may create and enhance groundwater flow channels, the chemical dissolution-front instability (CDFI) can control the quality of groundwater. This paper presents the theoretical analyses of porosity-permeability relationship effects on the CDFI in water-saturated porous rocks. Since the CDFI in a water-rock reaction system can be assessed by comparing the comprehensive dimensionless dynamic characteristic (CDDC) number with the corresponding critical CDDC number of the geochemical dissolution system, it is necessary to investigate theoretically how different porosity-permeability relationships can affect the CDDC number and critical CDDC number of a water-rock reaction system. With the commonly-used Kozeny-Carman (KC) formula taken as a reference porosity-permeability formula, the permeability variation indicator (PVI), which is defined as the ratio of the permeability obtained from any porosity-permeability formula to that obtained from the KC formula, is proposed to reflect the effect of the porosity-permeability formula on the CDFI in a water-rock reaction system. The theoretical results demonstrated that: (1) since the porosity-permeability formula with a higher PVI can result in a stronger Darcy flow velocity, it may have a significant influence on the CDFI in the water-rock reaction system. (2) With an increase in the PVI of a porosity-permeability formula, there is a decrease in the critical CDDC number of the water-rock reaction system. This means that the porous rock with a higher PVI can enable the CDFI to take place much easier in the water-rock reaction system. (3) The use of the porosity-permeability formula with a higher PVI can also cause an increase in both the dimensionless growth rate of a perturbation and the propagation speed of the chemical dissolution front in the water-rock reaction system.

  15. Evaluation of impact factors on PM2.5 based on long-term chemical components analyses in the megacity Beijing, China.

    PubMed

    Chen, Yuan; Schleicher, Nina; Cen, Kuang; Liu, Xiuli; Yu, Yang; Zibat, Volker; Dietze, Volker; Fricker, Mathieu; Kaminski, Uwe; Chen, Yizhen; Chai, Fahe; Norra, Stefan

    2016-07-01

    Nine years of sampling and analyses of fine particles (PM2.5) were performed in Beijing from 2005 to 2013. Twenty-seven chemical elements and black carbon (BC) in PM2.5 were analyzed in order to study chemical characteristics and temporal distribution of Beijing aerosols. Principle component analysis defined different types of elemental sources, based on which, the influences of a variety of anthropogenic activities including governmental intervention measures and natural sources on air quality were evaluated. For the first time, Ga is used as a tracer element for heating activities mainly using coal in Beijing, due to its correlation with BC and coal combustion, as well as its concentration variation between the heating- and non-heating periods. The traffic restrictions effectively reduced emissions of relevant heavy metals such as As, Cd, Sn and Sb. The expected long-term effectiveness of the steel smelters relocation was not observed due to the nearby relocation with increased capacity. Firework display during every Chinese spring festival season and special events such as the Olympic Games resulted in several times higher concentrations of K, Sr and Ba than other days and thus they were proposed as tracers for firework display. The impacts of all these factors were quantified and evaluated. Sand dust or dust storms induced higher concentrations of geogenic elements in PM2.5 compared to non-dust days. Sustainable mitigation measures, such as traffic restrictions, are necessary to be continued and improved to obtain more "blue sky" days in the future. PMID:27115848

  16. Chemical analyses of soil samples collected from the vicinity of the thermal test complex at Sandia National Laboratories, New Mexico environs, 2006.

    SciTech Connect

    Miller, Mark Laverne; Nieto, Danielle M.

    2007-01-01

    In the summer of 2006, the Environmental Programs and Assurance Department of Sandia National Laboratories in Albuquerque, New Mexico (SNL/NM), collected surface soil samples at 37 locations within one mile of the vicinity of the newly constructed Thermal Test Complex (TTC) for the purpose of determining baseline conditions against which potential future impacts to the environs from operations at the facility could be assessed. These samples were submitted to an offsite analytical laboratory for metal-in-soil analyses. This work provided the SNL Environmental Programs and Assurance Department with a sound baseline data reference set against which to assess potential future operational impacts at the TTC. In addition, it demonstrates the commitment that the Laboratories have to go beyond mere compliance to achieve excellence in its operations. This data are presented in graphical format with narrative commentaries on particular items of interest.

  17. Effect of liberibacter infection (huanglongbing disease) of citrus on orange fruit physiology and fruit/fruit juice quality: chemical and physical analyses.

    PubMed

    Baldwin, Elizabeth; Plotto, Anne; Manthey, John; McCollum, Greg; Bai, Jinhe; Irey, Mike; Cameron, Randall; Luzio, Gary

    2010-01-27

    More than 90% of oranges in Florida are processed, and since Huanglongbing (HLB) disease has been rumored to affect fruit flavor, chemical and physical analyses were conducted on fruit and juice from healthy (Las -) and diseased (Las +) trees on three juice processing varieties over two seasons, and in some cases several harvests. Fruit, both asymptomatic and symptomatic for the disease, were used, and fresh squeezed and processed/pasteurized juices were evaluated. Fruit and juice characteristics measured included color, size, solids, acids, sugars, aroma volatiles, ascorbic acid, secondary metabolites, pectin, pectin-demethylating enzymes, and juice cloud. Results showed that asymptomatic fruit from symptomatic trees were similar to healthy fruit for many of the quality factors measured, but that juice from asymptomatic and especially symptomatic fruits were often higher in the bitter compounds limonin and nomilin. However, values were generally below reported taste threshold levels, and only symptomatic fruit seemed likely to cause flavor problems. There was variation due to harvest date, which was often greater than that due to disease. It is likely that the detrimental flavor attributes of symptomatic fruit (which often drop off the tree) will be largely diluted in commercial juice blends that include juice from fruit of several varieties, locations, and seasons. PMID:20030384

  18. Effect of liberibacter infection (huanglongbing disease) of citrus on orange fruit physiology and fruit/fruit juice quality: chemical and physical analyses.

    PubMed

    Baldwin, Elizabeth; Plotto, Anne; Manthey, John; McCollum, Greg; Bai, Jinhe; Irey, Mike; Cameron, Randall; Luzio, Gary

    2010-01-27

    More than 90% of oranges in Florida are processed, and since Huanglongbing (HLB) disease has been rumored to affect fruit flavor, chemical and physical analyses were conducted on fruit and juice from healthy (Las -) and diseased (Las +) trees on three juice processing varieties over two seasons, and in some cases several harvests. Fruit, both asymptomatic and symptomatic for the disease, were used, and fresh squeezed and processed/pasteurized juices were evaluated. Fruit and juice characteristics measured included color, size, solids, acids, sugars, aroma volatiles, ascorbic acid, secondary metabolites, pectin, pectin-demethylating enzymes, and juice cloud. Results showed that asymptomatic fruit from symptomatic trees were similar to healthy fruit for many of the quality factors measured, but that juice from asymptomatic and especially symptomatic fruits were often higher in the bitter compounds limonin and nomilin. However, values were generally below reported taste threshold levels, and only symptomatic fruit seemed likely to cause flavor problems. There was variation due to harvest date, which was often greater than that due to disease. It is likely that the detrimental flavor attributes of symptomatic fruit (which often drop off the tree) will be largely diluted in commercial juice blends that include juice from fruit of several varieties, locations, and seasons.

  19. A reliable monitoring of the biocompatibility of an effluent along an oxidative pre-treatment by sequential bioassays and chemical analyses.

    PubMed

    Amat, A M; Arques, A; García-Ripoll, A; Santos-Juanes, L; Vicente, R; Oller, I; Maldonado, M I; Malato, S

    2009-02-01

    A new approach to assess biocompatibility of an effluent, based on combination of different bioassays and chemical analyses, has been tested using a mixture of four commercial pesticides treated by a solar photo-Fenton as target effluent. A very fast elimination of the pesticides occurred (all of them were below detection limit at t30W=36 min), but mineralisation was a more time-consuming process, due to the formation of organic intermediates and to the presence of solvents, as shown by GC-MS analysis. Measurements based on activated sludge indicated that detoxification was coincident with the removal of the active ingredients, while more sensitive Vibrio fischeri bacterium showed significant toxicity until the end of the experiment, although the effluent might be compatible with biological processes. Biodegradability of the solutions was enhanced by the photochemical process, to reach BOD5/COD ratios above 0.8. Longer time bioassays, such as the Zahn-Wellens' test, support the applicability of coupling photochemical with activated sludge-based biological processes to deal with these effluents.

  20. The Chemical Decomposition of 5-aza-2′-deoxycytidine (Decitabine): Kinetic Analyses and Identification of Products by NMR, HPLC, and Mass Spectrometry

    PubMed Central

    Rogstad, Daniel K.; Herring, Jason L.; Theruvathu, Jacob A.; Burdzy, Artur; Perry, Christopher C.; Neidigh, Jonathan W.; Sowers, Lawrence C.

    2014-01-01

    The nucleoside analog 5-aza-2′-deoxycytidine (Decitabine, DAC) is one of several drugs in clinical use that inhibit DNA methyltransferases, leading to a decrease of 5-methylcytosine in newly replicated DNA and subsequent transcriptional activation of genes silenced by cytosine methylation. In addition to methyltransferase inhibition, DAC has demonstrated toxicity and potential mutagenicity, and can induce a DNA-repair response. The mechanisms accounting for these events are not well understood. DAC is chemically unstable in aqueous solutions, but there is little consensus between previous reports as to its half-life and corresponding products of decomposition at physiological temperature and pH, potentially confounding studies on its mechanism of action and long-term use in humans. Here we have employed a battery of analytical methods to estimate kinetic rates and to characterize DAC decomposition products under conditions of physiological temperature and pH. Our results indicate that DAC decomposes into a plethora of products, formed by hydrolytic opening and deformylation of the triazine ring, in addition to anomerization and possibly other changes in the sugar ring structure. We also discuss the advantages and problems associated with each analytical method used. The results reported here will facilitate ongoing studies and clinical trials aimed at understanding the mechanisms of action, toxicity, and possible mutagenicity of DAC and related analogs. PMID:19480391

  1. A tutorial for analysing the cost-effectiveness of alternative methods for assessing chemical toxicity: the case of acute oral toxicity prediction.

    PubMed

    Norlen, Hedvig; Worth, Andrew P; Gabbert, Silke

    2014-05-01

    Compared with traditional animal methods for toxicity testing, in vitro and in silico methods are widely considered to permit a more cost-effective assessment of chemicals. However, how to assess the cost-effectiveness of alternative methods has remained unclear. This paper offers a user-oriented tutorial for applying cost-effectiveness analysis (CEA) to alternative (non-animal) methods. The purpose is to illustrate how CEA facilitates the identification of the alternative method, or the combination of methods, that offers the highest information gain per unit of cost. We illustrate how information gains and costs of single methods and method combinations can be assessed. By using acute oral toxicity as an example, we apply CEA to a set of four in silico methods (ToxSuite, TOPKAT, TEST, ADMET Predictor), one in vitro method (the 3T3 Neutral Red Uptake cytotoxicity assay), and various combinations of these methods. Our results underline that in silico tools are more cost-effective than the in vitro test. Battery combinations of alternative methods, however, do not necessarily outperform single methods, because additional information gains from the battery are easily outweighed by additional costs. PMID:24901905

  2. Increased pattern transfer fidelity of ZEP 520A during reactive ion etching through chemical modifications by additional dosing of the electron beam resist

    SciTech Connect

    Czaplewski, D. A.; Ocola, L. E.

    2011-01-01

    This article describes a postdevelopment, additional electron exposure to enhance the etch selectivity and improve pattern transfer fidelity of an electron beam resist, ZEP 520A, through chemical changes of the resist. After the critical features were patterned and developed, the resist was exposed at 5 kV accelerating voltage to a second dose of electrons ranging from 300 to 300,000 {micro}C/cm{sup 2}. The etch rate of the resist decreased by approximately 25% in a CHF{sub 3} and O{sub 2} plasma. More critically, the fidelity of the pattern transfer was improved. Infrared and Raman spectroscopies were used to characterize the resist before and after electron beam exposure for doses up to 3000 {micro}C/cm{sup 2}. The carbonyl bonding in the polymer showed significant changes after electron beam exposure that can be associated with improvement in the etch performance of this resist.

  3. Increased pattern transfer fidelity ZEP 520A during reactive ion etching through chemical modifications by additional dosing of the electron beam resist.

    SciTech Connect

    Czaplewski, D. A.; Ocola, L. E.

    2011-03-01

    This article describes a postdevelopment, additional electron exposure to enhance the etch selectivity and improve pattern transfer fidelity of an electron beam resist, ZEP 520A, through chemical changes of the resist. After the critical features were patterned and developed, the resist was exposed at 5 kV accelerating voltage to a second dose of electrons ranging from 300 to 300,000 {micro}C/cm{sup 2}. The etch rate of the resist decreased by approximately 25% in a CHF{sub 3} and O{sub 2} plasma. More critically, the fidelity of the pattern transfer was improved. Infrared and Raman spectroscopies were used to characterize the resist before and after electron beam exposure for doses up to 3000 {micro}C/cm{sup 2}. The carbonyl bonding in the polymer showed significant changes after electron beam exposure that can be associated with improvement in the etch performance of this resist.

  4. Radiological, physical, and chemical characterization of additional alpha contaminated and mixed low-level waste for treatment at the advanced mixed waste treatment project

    SciTech Connect

    Hutchinson, D.P.

    1995-07-01

    This document provides physical, chemical, and radiological descriptive information for a portion of mixed waste that is potentially available for private sector treatment. The format and contents are designed to provide treatment vendors with preliminary information on the characteristics and properties for additional candidate portions of the Idaho National Engineering Laboratory (INEL) and offsite mixed wastes not covered in the two previous characterization reports for the INEL-stored low-level alpha-contaminated and transuranic wastes. This report defines the waste, provides background information, briefly reviews the requirements of the Federal Facility Compliance Act (P.L. 102-386), and relates the Site Treatment Plans developed under the Federal Facility Compliance Act to the waste streams described herein. Each waste is summarized in a Waste Profile Sheet with text, charts, and tables of waste descriptive information for a particular waste stream. A discussion of the availability and uncertainty of data for these waste streams precedes the characterization descriptions.

  5. The chemical conditions of the late Archean Hamersley basin inferred from whole rock and pyrite geochemistry with Δ33S and δ34S isotope analyses

    NASA Astrophysics Data System (ADS)

    Gregory, Daniel D.; Large, Ross R.; Halpin, Jacqueline A.; Steadman, Jeffery A.; Hickman, Arthur H.; Ireland, Trevor R.; Holden, Peter

    2015-01-01

    The well-preserved late Archean sedimentary rocks of the Fortescue and Hamersley Basins in Western Australia offer fascinating insights into early earth ocean chemistry prior to the Great Oxidation Event (GOE). In this study, we use a combination of whole rock geochemistry, LA-ICPMS trace element analysis of sedimentary pyrite and pyrrhotite and SHRIMP-SI sulfur isotope analyses to elucidate the chemical changes in these sedimentary rocks. These proxies are used to examine chemical conditions of the ocean during the late Archean. Two to three periods of oxygen enrichment prior to the deposition of banded iron formations (BIF) can be identified. One minor stage of general increase in whole rock enrichment factors and trace element content of pyrite is observed up stratigraphy in the Jeerinah Formation, Fortescue Basin and a more substantial stage is present in the Paraburdoo and Bee Gorge Members of the Wittenoom Formation, Hamersley Basin. Some of the trace element enrichments indicate organic matter burial flux (Ni, Cr, Zn, Co and Cu) which suggests an increase in biological productivity. If the increased biological activity reflects an increase in cyanobacteria activity then an associated increase in oxygen is likely to have occurred during the deposition of the Bee Gorge Member. An increase in atmospheric oxygen would result in continental weathering of sulfide and other minerals, increasing the trace element content of the water column via erosion and avoiding excessive depletion of trace elements due to drawdown in seawater. Since some of these trace elements may also be limiting nutrients (such as Mo and Se) for the cyanobacteria, the degree of biological productivity may have further increased due to the increasing amount of trace elements introduced by oxygenation in a positive feedback loop. These periods of increased productivity and oxygen rise stopped prior to the onset of BIF deposition in the Hamersley Basin. This may be due to the ocean reaching an

  6. Risk assessment of PCDD/Fs levels in human tissues related to major food items based on chemical analyses and micro-EROD assay.

    PubMed

    Tsang, H L; Wu, S C; Wong, C K C; Leung, C K M; Tao, S; Wong, M H

    2009-10-01

    Nine groups of food items (freshwater fish, marine fish, pork, chicken, chicken eggs, leafy, non-leafy vegetables, rice and flour) and three types of human samples (human milk, maternal serum and cord serum) were collected for the analysis of PCDD/Fs. Results of chemical analysis revealed PCDD/Fs concentrations (pg g(-1) fat) in the following ascending order: pork (0.289 pg g(-1) fat), grass carp (Ctenopharyngodon idellus) (freshwater fish) (0.407), golden thread (Nemipterus virgatus) (marine fish) (0.511), chicken (0.529), mandarin fish (Siniperca kneri) (marine fish) (0.535), chicken egg (0.552), and snubnose pompano (Trachinotus blochii) (marine fish) (1.219). The results of micro-EROD assay showed relatively higher PCDD/Fs levels in fish (2.65 pg g(-1) fat) when compared with pork (0.47), eggs (0.33), chicken (0.13), flour (0.07), vegetables (0.05 pg g(-1) wet wt) and rice (0.05). The estimated average daily intake of PCDD/Fs of 3.51 pg EROD-TEQ/kg bw/day was within the range of WHO Tolerable Daily Intake (1-4 pg WHO-TEQ/kg bw/day) and was higher than the Provisional Tolerable Daily Intake (PMTL) (70 pg for dioxins and dioxin-like PCBs) recommended by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) [Joint FAO/WHO Expert Committee on Food Additives (JECFA), Summary and conclusions of the fifty-seventh meeting, JECFA, 2001.]. Nevertheless, the current findings were significantly lower than the TDI (14 pg WHO-TEQ/kg/bw/day) recommended by the Scientific Committee on Food of the Europe Commission [European Scientific Committee on Food (EU SCF), Opinions on the SCF on the risk assessment of dioxins and dioxin-like PCBs in food, 2000.]. However, it should be noted that micro-EROD assay overestimates the PCDD/Fs levels by 2 to 7 folds which may also amplify the PCDD/Fs levels accordingly. Although the levels of PCDD/Fs obtained from micro-EROD assay were much higher than those obtained by chemical analysis by 2 to 7 folds, it provides a cost-effective and

  7. Cytological and Comparative Proteomic Analyses on Male Sterility in Brassica napus L. Induced by the Chemical Hybridization Agent Monosulphuron Ester Sodium

    PubMed Central

    Li, Zhanjie; Cui, Jianmin; Hu, Shengwu; Zhao, Huixian; Chen, Mingshun

    2013-01-01

    Male sterility induced by a chemical hybridization agent (CHA) is an important tool for utilizing crop heterosis. Monosulphuron ester sodium (MES), a new acetolactate synthase-inhibitor herbicide belonging to the sulphonylurea family, has been developed as an effective CHA to induce male sterility in rapeseed (Brassica napus L.). To understand MES-induced male sterility in rapeseed better, comparative cytological and proteomic analyses were conducted in this study. Cytological analysis indicated that defective tapetal cells and abnormal microspores were gradually generated in the developing anthers of MES-treated plants at various development stages, resulting in unviable microspores and male sterility. A total of 141 differentially expressed proteins between the MES-treated and control plants were revealed, and 131 of them were further identified by MALDI-TOF/TOF MS. Most of these proteins decreased in abundance in tissues of MES-treated rapeseed plants, and only a few increased. Notably, some proteins were absent or induced in developing anthers after MES treatment. These proteins were involved in several processes that may be crucial for tapetum and microspore development. Down-regulation of these proteins may disrupt the coordination of developmental and metabolic processes, resulting in defective tapetum and abnormal microspores that lead to male sterility in MES-treated plants. Accordingly, a simple model of CHA-MES-induced male sterility in rapeseed was established. This study is the first cytological and dynamic proteomic investigation on CHA-MES-induced male sterility in rapeseed, and the results provide new insights into the molecular events of male sterility. PMID:24244648

  8. Effects of water additions, chemical amendments, and plants on in situ measures of nutrient bioavailability in calcareous soils of southeastern Utah, USA

    USGS Publications Warehouse

    Miller, M.E.; Belnap, J.; Beatty, S.W.; Webb, B.L.

    2006-01-01

    We used ion-exchange resin bags to investigate effects of water additions, chemical amendments, and plant presence on in situ measures of nutrient bioavailability in conjunction with a study examining soil controls of ecosystem invasion by the exotic annual grass Bromus tectorum L. At five dryland sites in southeastern Utah, USA, resin bags were buried in experimental plots randomly assigned to combinations of two watering treatments (wet and dry), four chemical-amendment treatments (KCl, MgO, CaO, and no amendment), and four plant treatments (B. tectorum alone, the perennial bunchgrass Stipa hymenoides R. & S. alone, B. tectorum and S. hymenoides together, and no plants). Resin bags were initially buried in September 1997; replaced in January, April, and June 1998; and removed at the end of the study in October 1998. When averaged across watering treatments, plots receiving KCl applications had lower resin-bag NO 3- than plots receiving no chemical amendments during three of four measurement periods-probably due to NO 3- displacement from resin bags by Cl- ions. During the January-April period, KCl application in wet plots (but not dry plots) decreased resin-bag NH 4+ and increased resin-bag NO 3- . This interaction effect likely resulted from displacement of NH 4+ from resins by K+ ions, followed by nitrification and enhanced NO 3- capture by resin bags. In plots not receiving KCl applications, resin-bag NH 4+ was higher in wet plots than in dry plots during the same period. During the January-April period, resin-bag measures for carbonate-related ions HPO 42- , Ca2+, and Mn2+ tended to be greater in the presence of B. tectorum than in the absence of B. tectorum. This trend was evident only in wet plots where B. tectorum densities were much higher than in dry plots. We attribute this pattern to the mobilization of carbonate-associated ions by root exudates of B. tectorum. These findings indicate the importance of considering potential indirect effects of soil

  9. Comparing pre- and post-chemical abrasion ages for Miocene Peach Springs Tuff zircon from ID-TIMS and SIMS analyses

    NASA Astrophysics Data System (ADS)

    Lidzbarski, M. I.; Mundil, R.; Miller, J. S.; Vazquez, J. A.

    2012-12-01

    The Miocene Peach Spring Tuff (PST) is a voluminous (>600 km3), zoned ignimbrite (trachyte to high-SiO2 rhyolite) that is exposed widely in eastern California, western Arizona, and southernmost Nevada, which was erupted from the Silver Creek caldera in the southwestern Black Mountains, AZ. PST serves as a regionally widespread marker unit and its eruption age has been determined to 18.8 to 18.9 Ma by 40Ar/39Ar methods, when corrected for systematic bias and normalized to the U-Pb system (Renne et al., 2010,). We performed ion-microprobe (SIMS) U-Pb dating of zircon from individual pumice clasts from PST to evaluate the growth history of zircon in the PST magma system. Sectioned, polished zircon from conventional epoxy mounts allows dating of internal growth domains (e.g. cores, interiors, and near-rim), whereas mounting unpolished zircon in indium and analyzing unpolished crystal faces provides a means to selectively sample the final increments of crystal growth (Reid and Coath, 2000). Combining U-Pb ages of unpolished zircon rims with near-rim interior analyses on sectioned grains yields a mean age of ca. 18.3 Ma, whereas ages of cores of sectioned crystals yield a mean of ca. 18.9 Ma. Several zircons have rim and/or core ages that are several hundred thousand years older or younger than these means (up to 1 m.y. total spread), although the uncertainties for individual SIMS ages are 2 to 5% (2 sigma uncertainty). Therefore, the distribution of ages is challenging to resolve. A modest number of the older grains are plausibly recycled antecrysts, but we suspect that the youngest zircons may have experienced Pb-loss. Failure to account for the possibility of inheritance and Pb-loss may lead to erroneous interpretations about crystallization in the PST system. In order to evaluate and mitigate the effects of Pb-loss, we employed the chemical abrasion (CA) technique of Mattinson (2005), which effectively eliminates domains in zircon that have suffered Pb-loss, and

  10. Multielement chemical and statistical analyses from a uranium hydrogeochemical and stream-sediment survey in and near the Elkhorn Mountains, Jefferson County, Montana; Part I, Surface water

    USGS Publications Warehouse

    Suits, V.J.; Wenrich, K.J.

    1982-01-01

    Fifty-two surface-water samples, collected from an area south of Helena, Jefferson County, were analyzed for 51 chemical species. Of these variables, 35 showed detectable variation over the area, and 29 were utilized in a correlation analysis. Two populations are distinguished in the collected samples and are especially evident in the plot of Ca versus U. Samples separated on the basis of U versus Ca proved to represent drainage areas of two differing lithologies. One group was from waters that drain the Boulder batholith, the other from those that drain the Elkhorn Mountains volcanic rocks. These two groups of samples, in general, proved to have parallel but different linear trends between U and other elements. Therefore, the two groups of samples were treated separately in the statistical analyses. Over the area that drains the Boulder batholith, U concentrations in water ranged from 0.37 to 13.0 ?g/l , with a mean of 1.9 ?g/l. The samples from streams draining volcanic areas ranged from 0.04 to 1.5 ?g/l, with a mean of 0.42 ?g/l. The highest U values (12 and 13 ?g/l) occur along Badger Creek, Rawhide Creek, Little Buffalo Gulch, and an unnamed tributary to Clancy Creek. Conductivity, hardness, Ba, Ca, CI, K, Mg, Na and Sr are significantly correlated with U at or better than the 95 percent confidence limit in both populations. For water draining the Boulder batholith, uranium correlates significantly with akalinity, pH, bicarbonate, Li, Mo, NO2+NO3, P04, SiO2, SO4, F, and inorganic carbon. These correlations are similar to those found in a previous study of water samples in north-central New Mexico (Wenrich-Verbeek, 1977b). Uranium in water from the volcanic terrane does not show correlations with any of the above constituents, but does correlate well with V. This relationship with V is absent within the Boulder batholith samples.

  11. Possibility of controlling the chemical pattern of He and Ar “guided streamers” by means of N{sub 2} or O{sub 2} additives

    SciTech Connect

    Gazeli, K.; Svarnas, P. E-mail: franck.clement@univ-pau.fr; Held, B.; Clément, F. E-mail: franck.clement@univ-pau.fr; Marlin, L.

    2015-03-07

    Plasma chemistry at atmospheric pressure and low temperature has met an increased interest due to the effective production of reactive species (mainly reactive nitrogen species and reactive oxygen species) which are demanded in many applications like in biomedicine. Τhe generation of such emissive reactive species is herein studied. A single parameter, i.e., the gas composition, is tuned and abundant chemical species are obtained in a quite controllable manner. The system refers to a small dielectric barrier discharge based reactor fed with He–N{sub 2}/O{sub 2} or Ar–N{sub 2}/O{sub 2} gases, which provides plasma in the form of “guided streamers.” The plasma is sustained by positive high voltage pulses, and the emissive transitions versus the gas composition is determined by UV-VIS optical emission spectroscopy. The relative intensities of emissive species are recorded in the ambient air where the streamers propagate. The evolution of dominant species as a function of the gas composition is mapped, and optimal conditions in terms of species production are clearly revealed. The results show that additives do not necessarily enhance the density of all species, implying the need for plasma chemistry optimization in respect to every application. The study is extended inside the reactor, supporting the above statements. Finally, the rotational and vibrational distributions of critical probe molecules are recorded, testing the dependence of the gas temperature and energy transfer, respectively, on the gas composition.

  12. Chemical xenobiotics and mitochondrial autoantigens in primary biliary cirrhosis: identification of antibodies against a common environmental, cosmetic, and food additive, 2-octynoic acid.

    PubMed

    Amano, Katsushi; Leung, Patrick S C; Rieger, Roman; Quan, Chao; Wang, Xiaobing; Marik, Jan; Suen, Yat Fan; Kurth, Mark J; Nantz, Michael H; Ansari, Aftab A; Lam, Kit S; Zeniya, Mikio; Matsuura, Eiji; Coppel, Ross L; Gershwin, M Eric

    2005-05-01

    Emerging evidence has suggested environmental factors as causative agents in the pathogenesis of primary biliary cirrhosis (PBC). We have hypothesized that in PBC the lipoyl domain of the immunodominant E2 component of pyruvate dehydrogenase (PDC-E2) is replaced by a chemical xenobiotic mimic, which is sufficient to break self-tolerance. To address this hypothesis, based upon our quantitative structure-activity relationship data, a total of 107 potential xenobiotic mimics were coupled to the lysine residue of the immunodominant 15 amino acid peptide of the PDC-E2 inner lipoyl domain and spotted on microarray slides. Sera from patients with PBC (n = 47), primary sclerosing cholangitis (n = 15), and healthy volunteers (n = 20) were assayed for Ig reactivity. PBC sera were subsequently absorbed with native lipoylated PDC-E2 peptide or a xenobiotically modified PDC-E2 peptide, and the remaining reactivity analyzed. Of the 107 xenobiotics, 33 had a significantly higher IgG reactivity against PBC sera compared with control sera. In addition, 9 of those 33 compounds were more reactive than the native lipoylated peptide. Following absorption, 8 of the 9 compounds demonstrated cross-reactivity with lipoic acid. One compound, 2-octynoic acid, was unique in both its quantitative structure-activity relationship analysis and reactivity. PBC patient sera demonstrated high Ig reactivity against 2-octynoic acid-PDC-E2 peptide. Not only does 2-octynoic acid have the potential to modify PDC-E2 in vivo but importantly it was/is widely used in the environment including perfumes, lipstick, and many common food flavorings. PMID:15845458

  13. Seismic Absorption and Modulus Measurements in Porous Rocks in Lab and Field: Physical, Chemical, and Biological Effects of Fluids (Detecting a Biosurfactant Additive in a Field Irrigation Experiment)

    SciTech Connect

    Spetzler, Hartmut

    2006-05-01

    We have been exploring a new technology that is based on using low-frequency seismic attenuation data to monitor changes in fluid saturation conditions in two-fluid phase porous materials. The seismic attenuation mechanism is related to the loss of energy due to the hysteresis of resistance to meniscus movement (changes in surface tension, wettability) when a pore containing two fluids is stressed at very low frequencies (< 10 Hz). This technology has potential applications to monitoring changes in (1) leakage at buried waste sites, (2) contaminant remediation, and (3) flooding during enhanced petroleum recovery. We have concluded a three year field study at the Maricopa Agricultural Center site of the University of Arizona. Three sets of instruments were installed along an East-West line perpendicular to the 50m by 50m inigation site. Each set of instruments consisted of one three component seismometer and one tiltmeter. Microseisms and solid Earth-tides served as strain sources. The former have a power peak at a period of about 6 seconds and the tides have about two cycles per day. Installation of instruments commenced in late summer of 2002. The instruments operated nearly continuously until April 2005. During the fall of 2003 the site was irrigated with water and one year later with water containing 150 ppm of a biosurfactant additive. This biodegradable additive served to mimic a class of contaminants that change the surface tension of the inigation fluid. Tilt data clearly show tidal tilts superimposed on local tilts due to agricultural irrigation and field work. When the observed signals were correlated with site specific theoretical tilt signals we saw no anomalies for the water irrigation in 2003, but large anomalies on two stations for the surfactant irrigation in 2004. Occasional failures of seismometers as well as data acquisition systems contributed to less than continuous coverage. These data are noisier than the tilt data, but do also show possible

  14. In situ sulfur isotopes (δ(34)S and δ(33)S) analyses in sulfides and elemental sulfur using high sensitivity cones combined with the addition of nitrogen by laser ablation MC-ICP-MS.

    PubMed

    Fu, Jiali; Hu, Zhaochu; Zhang, Wen; Yang, Lu; Liu, Yongsheng; Li, Ming; Zong, Keqing; Gao, Shan; Hu, Shenghong

    2016-03-10

    The sulfur isotope is an important geochemical tracer in diverse fields of geosciences. In this study, the effects of three different cone combinations with the addition of N2 on the performance of in situ S isotope analyses were investigated in detail. The signal intensities of S isotopes were improved by a factor of 2.3 and 3.6 using the X skimmer cone combined with the standard sample cone or the Jet sample cone, respectively, compared with the standard arrangement (H skimmer cone combined with the standard sample cone). This signal enhancement is important for the improvement of the precision and accuracy of in situ S isotope analysis at high spatial resolution. Different cone combinations have a significant effect on the mass bias and mass bias stability for S isotopes. Poor precisions of S isotope ratios were obtained using the Jet and X cones combination at their corresponding optimum makeup gas flow when using Ar plasma only. The addition of 4-8 ml min(-1) nitrogen to the central gas flow in laser ablation MC-ICP-MS was found to significantly enlarge the mass bias stability zone at their corresponding optimum makeup gas flow in these three different cone combinations. The polyatomic interferences of OO, SH, OOH were also significantly reduced, and the interference free plateaus of sulfur isotopes became broader and flatter in the nitrogen mode (N2 = 4 ml min(-1)). However, the signal intensity of S was not increased by the addition of nitrogen in this study. The laser fluence and ablation mode had significant effects on sulfur isotope fractionation during the analysis of sulfides and elemental sulfur by laser ablation MC-ICP-MS. The matrix effect among different sulfides and elemental sulfur was observed, but could be significantly reduced by line scan ablation in preference to single spot ablation under the optimized fluence. It is recommended that the d90 values of the particles in pressed powder pellets for accurate and precise S isotope analysis

  15. In situ sulfur isotopes (δ(34)S and δ(33)S) analyses in sulfides and elemental sulfur using high sensitivity cones combined with the addition of nitrogen by laser ablation MC-ICP-MS.

    PubMed

    Fu, Jiali; Hu, Zhaochu; Zhang, Wen; Yang, Lu; Liu, Yongsheng; Li, Ming; Zong, Keqing; Gao, Shan; Hu, Shenghong

    2016-03-10

    The sulfur isotope is an important geochemical tracer in diverse fields of geosciences. In this study, the effects of three different cone combinations with the addition of N2 on the performance of in situ S isotope analyses were investigated in detail. The signal intensities of S isotopes were improved by a factor of 2.3 and 3.6 using the X skimmer cone combined with the standard sample cone or the Jet sample cone, respectively, compared with the standard arrangement (H skimmer cone combined with the standard sample cone). This signal enhancement is important for the improvement of the precision and accuracy of in situ S isotope analysis at high spatial resolution. Different cone combinations have a significant effect on the mass bias and mass bias stability for S isotopes. Poor precisions of S isotope ratios were obtained using the Jet and X cones combination at their corresponding optimum makeup gas flow when using Ar plasma only. The addition of 4-8 ml min(-1) nitrogen to the central gas flow in laser ablation MC-ICP-MS was found to significantly enlarge the mass bias stability zone at their corresponding optimum makeup gas flow in these three different cone combinations. The polyatomic interferences of OO, SH, OOH were also significantly reduced, and the interference free plateaus of sulfur isotopes became broader and flatter in the nitrogen mode (N2 = 4 ml min(-1)). However, the signal intensity of S was not increased by the addition of nitrogen in this study. The laser fluence and ablation mode had significant effects on sulfur isotope fractionation during the analysis of sulfides and elemental sulfur by laser ablation MC-ICP-MS. The matrix effect among different sulfides and elemental sulfur was observed, but could be significantly reduced by line scan ablation in preference to single spot ablation under the optimized fluence. It is recommended that the d90 values of the particles in pressed powder pellets for accurate and precise S isotope analysis

  16. Summary of chemical data from onsite and laboratory analyses of groundwater samples from the surficial aquifer, Las Vegas, Nevada, April and August 1993 and September 1994

    USGS Publications Warehouse

    Reddy, Michael M.; Gunther, Charmaine D.

    2012-01-01

    Samples were collected from groundwater wells in and about the city of Las Vegas, Nevada, and were analyzed for selected major, minor and trace constituents. Analyses of blank and reference samples are summarized as mean and standard deviation values for all positive results.

  17. Results of chemical analyses of soil, shale, and soil/shale extract from the Mancos Shale formation in the Gunnison Gorge National Conservation Area, southwestern Colorado, and at Hanksville, Utah

    USGS Publications Warehouse

    Tuttle, Michele L.W.; Fahy, Juli; Grauch, Richard I.; Ball, Bridget A.; Chong, Geneva W.; Elliott, John G.; Kosovich, John J.; Livo, Keith E.; Stillings, Lisa L.

    2007-01-01

    Results of chemical and some isotopic analyses of soil, shale, and water extracts collected from the surface, trenches, and pits in the Mancos Shale are presented in this report. Most data are for sites on the Gunnison Gorge National Conservation Area (GGNCA) in southwestern Colorado. For comparison, data from a few sites from the Mancos landscape near Hanksville, Utah, are included. Twelve trenches were dug on the GGNCA from which 258 samples for whole-rock (total) analyses and 187 samples for saturation paste extracts were collected. Sixteen of the extract samples were duplicated and subjected to a 1:5 water extraction for comparison. A regional soil survey across the Mancos landscape on the GGNCA generated 253 samples for whole-rock analyses and saturation paste extractions. Seventeen gypsum samples were collected on the GGNCA for sulfur and oxygen isotopic analysis. Sixteen samples were collected from shallow pits in the Mancos Shale near Hanksville, Utah.

  18. Preparation and analyses of low-rank coals for combustion applications. Second quarterly report, January 1, 1985-March 31, 1985. [Physical and chemical cleaning

    SciTech Connect

    Smit, F.J.; Maas, D.J.

    1985-04-30

    This report covers the second quarter of activity on an 18-month project to prepare low-rank coal (LRC) fuel for research applications in DOE advanced combustion technologies programs. Coals from five mines were characterized by physical and chemical cleaning and hot water drying amenability tests. Subbituminous coal from the Eagle Butte Mine was selected from the five for future use as feed stock for production of bulk lots of low ash and low sodium LRC and LRC slurry fuels. The amenability tests indicated that a combination of physical and chemical cleaning would produce a fuel containing 1.36% ash, 8 ppM Na/sub 2/O and 18 ppM K/sub 2/O from the Eagle Butte coal on a dry basis. A micronized slurry loading of 57.5% coal was projected for the hot-water dried coal. 8 refs., 13 figs., 26 tabs.

  19. Addition of docetaxel or bisphosphonates to standard of care in men with localised or metastatic, hormone-sensitive prostate cancer: a systematic review and meta-analyses of aggregate data

    PubMed Central

    Vale, Claire L; Burdett, Sarah; Rydzewska, Larysa H M; Albiges, Laurence; Clarke, Noel W; Fisher, David; Fizazi, Karim; Gravis, Gwenaelle; James, Nicholas D; Mason, Malcolm D; Parmar, Mahesh K B; Sweeney, Christopher J; Sydes, Matthew R; Tombal, Bertrand; Tierney, Jayne F

    2016-01-01

    docetaxel for men with locally advanced disease (M0). Survival results from three (GETUG-12, RTOG 0521, STAMPEDE) of these trials (2121 [53%] of 3978 men) showed no evidence of a benefit from the addition of docetaxel (HR 0·87 [95% CI 0·69–1·09]; p=0·218), whereas failure-free survival data from four (GETUG-12, RTOG 0521, STAMPEDE, TAX 3501) of these trials (2348 [59%] of 3978 men) showed that docetaxel improved failure-free survival (0·70 [0·61–0·81]; p<0·0001), which translates into a reduced absolute 4-year failure rate of 8% (5–10). We identified seven eligible randomised controlled trials of bisphosphonates for men with M1 disease. Survival results from three of these trials (2740 [88%] of 3109 men) showed that addition of bisphosphonates improved survival (0·88 [0·79–0·98]; p=0·025), which translates to 5% (1–8) absolute improvement, but this result was influenced by the positive result of one trial of sodium clodronate, and we found no evidence of a benefit from the addition of zoledronic acid (0·94 [0·83–1·07]; p=0·323), which translates to an absolute improvement in survival of 2% (−3 to 7). Of 17 trials of bisphosphonates for men with M0 disease, survival results from four trials (4079 [66%] of 6220 men) showed no evidence of benefit from the addition of bisphosphonates (1·03 [0·89–1·18]; p=0·724) or zoledronic acid (0·98 [0·82–1·16]; p=0·782). Failure-free survival definitions were too inconsistent for formal meta-analyses for the bisphosphonate trials. Interpretation The addition of docetaxel to standard of care should be considered standard care for men with M1 hormone-sensitive prostate cancer who are starting treatment for the first time. More evidence on the effects of docetaxel on survival is needed in the M0 disease setting. No evidence exists to suggest that zoledronic acid improves survival in men with

  20. Addition of docetaxel or bisphosphonates to standard of care in men with localised or metastatic, hormone-sensitive prostate cancer: a systematic review and meta-analyses of aggregate data

    PubMed Central

    Vale, Claire L; Burdett, Sarah; Rydzewska, Larysa H M; Albiges, Laurence; Clarke, Noel W; Fisher, David; Fizazi, Karim; Gravis, Gwenaelle; James, Nicholas D; Mason, Malcolm D; Parmar, Mahesh K B; Sweeney, Christopher J; Sydes, Matthew R; Tombal, Bertrand; Tierney, Jayne F

    2016-01-01

    docetaxel for men with locally advanced disease (M0). Survival results from three (GETUG-12, RTOG 0521, STAMPEDE) of these trials (2121 [53%] of 3978 men) showed no evidence of a benefit from the addition of docetaxel (HR 0·87 [95% CI 0·69–1·09]; p=0·218), whereas failure-free survival data from four (GETUG-12, RTOG 0521, STAMPEDE, TAX 3501) of these trials (2348 [59%] of 3978 men) showed that docetaxel improved failure-free survival (0·70 [0·61–0·81]; p<0·0001), which translates into a reduced absolute 4-year failure rate of 8% (5–10). We identified seven eligible randomised controlled trials of bisphosphonates for men with M1 disease. Survival results from three of these trials (2740 [88%] of 3109 men) showed that addition of bisphosphonates improved survival (0·88 [0·79–0·98]; p=0·025), which translates to 5% (1–8) absolute improvement, but this result was influenced by the positive result of one trial of sodium clodronate, and we found no evidence of a benefit from the addition of zoledronic acid (0·94 [0·83–1·07]; p=0·323), which translates to an absolute improvement in survival of 2% (−3 to 7). Of 17 trials of bisphosphonates for men with M0 disease, survival results from four trials (4079 [66%] of 6220 men) showed no evidence of benefit from the addition of bisphosphonates (1·03 [0·89–1·18]; p=0·724) or zoledronic acid (0·98 [0·82–1·16]; p=0·782). Failure-free survival definitions were too inconsistent for formal meta-analyses for the bisphosphonate trials. Interpretation The addition of docetaxel to standard of care should be considered standard care for men with M1 hormone-sensitive prostate cancer who are starting treatment for the first time. More evidence on the effects of docetaxel on survival is needed in the M0 disease setting. No evidence exists to suggest that zoledronic acid improves survival in men with M1 or M0 disease, and any potential benefit is probably small. Funding Medical Research Council UK. PMID

  1. Records of wells, drillers' logs, water-level measurements, and chemical analyses of ground water in Harris and Galveston counties, Texas, 1980-84

    USGS Publications Warehouse

    Williams, James F.; Coplin, L.S.; Ranzau, C.E.; Lind, W.B.; Bonnet, C.W.; Locke, Glenn L.

    1987-01-01

    Information on major new water wells in Harris and Galveston Counties was compiled by the U.S. Geological Survey from 1980 to 1984. This report presents the results of the hydro!ogic data collection on new large-capacity and other selected wells, including well location and completion data, drillers 1 logs of the strata penetrated, water levels, and chemical quality of the produced water. These water-well data are supplementary to similar data on older wells in these counties and to descriptive evaluations of the ground-water resources which have been published previously.

  2. Geology, coal resources, and chemical analyses of coal from the Fruitland Formation, Kimbeto EMRIA study site, San Juan County, New Mexico

    USGS Publications Warehouse

    Schneider, Gary B.; Hildebrand, Rick T.; Affolter, Ronald H.

    1979-01-01

    The Kimbeto EMRIA study site, an area of about 20 square miles (52 km2), is located on the south margin of the San Juan Basin on the gently northward-dipping strata of the Upper Cretaceous Fruitland Formation and the Kirtland Shale. The coal beds are mainly in the lower 150 feet (45 m) of the Fruitland Format ion. Coal resources--measured, indicated, and inferred--with less than 400 feet (120 m) of overburden in the site are 69,085,000 short tons (62,660,100 metric tons), 369,078,000 short tons (334,754,000 metric tons), and 177,803,000 short tons (161,267,000 metric tons) respectively. About 68 percent of these resources are overlain by 200 feet (60 m) or less of overburden. The apparent rank of the coal ranges from subbituminous B to subbituminous A. The average Btu/lb value of 14 core samples from the site on the as-received basis is 8,240 (4580 Kcal/kg), average ash content is 23.4 percent, and average sulfur content is 0.5 percent. Analyses of coal from the Kimbeto EMRIA study site show significantly higher ash content and significantly lower contents of volatile matter, fixed carbon, carbon, and a significantly lower heat of combustion when compared with other coal analyses from the Rocky Mountain province.

  3. Sociopolitical Analyses.

    ERIC Educational Resources Information Center

    Van Galen, Jane, Ed.; And Others

    1992-01-01

    This theme issue of the serial "Educational Foundations" contains four articles devoted to the topic of "Sociopolitical Analyses." In "An Interview with Peter L. McLaren," Mary Leach presented the views of Peter L. McLaren on topics of local and national discourses, values, and the politics of difference. Landon E. Beyer's "Educational Studies and…

  4. Conformation of the 3'-end of beet necrotic yellow vein benevirus RNA 3 analysed by chemical and enzymatic probing and mutagenesis.

    PubMed Central

    Lauber, E; Guilley, H; Richards, K; Jonard, G; Gilmer, D

    1997-01-01

    Secondary structure-sensitive chemical and enzymatic probes have been used to produce a model for the folding of the last 68 residues of the 3'-non-coding region of beet necrotic yellow vein benevirus RNA 3. The structure consists of two stem-loops separated by a single-stranded region. RNA 3-derived transcripts were produced containing mutations which either disrupted base pairing in the helices or maintained the helices but with alterations in the base pairing scheme. Other mutants contained substitutions in single-stranded regions (loops or bulged sequences). With a few exceptions all three types of mutation abolished RNA 3 replication in vivo, suggesting that both secondary structure and specific sequences are required for efficient recognition of the 3'-terminal region of RNA 3 by viral RNA-dependent RNA polymerase. PMID:9365250

  5. Use of radiation effects for a controlled change in the chemical composition and properties of materials by intentional addition or substitution of atoms of a certain kind

    SciTech Connect

    Gurovich, B. A.; Prikhod'ko, K. E. Kuleshova, E. A.; Maslakov, K. I.; Komarov, D. A.

    2013-06-15

    This study is a continuation of works [1-12] dealing with the field developed by the authors, namely, to widen the possibilities of radiation methods for a controlled change in the atomic composition and properties of thin-film materials. The effects under study serve as the basis for the following two methods: selective atom binding and selective atom substitution. Such changes in the atomic composition are induced by irradiation by mixed beams consisting of protons and other ions, the energy of which is sufficient for target atom displacements. The obtained experimental data demonstrate that the changes in the chemical composition of thin-film materials during irradiation by an ion beam of a complex composition take place according to mechanisms that differ radically from the well-known mechanisms controlling the corresponding chemical reactions in these materials. These radical changes are shown to be mainly caused by the accelerated ioninduced atomic displacements in an irradiated material during irradiation; that is, they have a purely radiation nature. The possibilities of the new methods for creating composite structures consisting of regions with a locally changed chemical composition and properties are demonstrated for a wide class of materials.

  6. Effect of V addition to Al and Al grain refined by Ti on chemical corrosion rates in NaOH solution with and without inhibitor at different temperatures

    NASA Astrophysics Data System (ADS)

    Zaid, Adnan I. O.; Al-Haj-Ali, Ahmad M.; Allawi, G. T. A.

    2014-06-01

    The paper presents the effect of vanadium addition to aluminum grain refined by titanium, in the range from 0.005 wt % to 0.236 wt %, on corrosion rate of these micro alloys in caustic soda (NaOH) solution at different temperatures. The corrosion rate decreased by the addition of any percent of vanadium at 25°C compared to pure Al. The corrosion rate increased with increase of solution temperature from 25 to 40 and 60 °C at any percent of vanadium addition. However, addition of vanadium reduced the corrosion rate at these temperatures at most wt.% of V addition. The maximum achieved reduction in corrosion rate due to vanadium addition was 40 % at 0.148 wt % and 60°C. The addition of 3 % potassium dichromate as corrosion inhibitor to NaOH solution reduced the average corrosion rates at any wt.% of vanadium. The inhibition efficiency ranged from 44- 58% at 25 °C and from 97-99% at 40 and 60°C.

  7. Evidence for heavy fuel oil combustion aerosols from chemical analyses at the island of Lampedusa: a possible large role of ships emissions in the Mediterranean

    NASA Astrophysics Data System (ADS)

    Becagli, S.; Sferlazzo, D. M.; Pace, G.; di Sarra, A.; Bommarito, C.; Calzolai, G.; Ghedini, C.; Lucarelli, F.; Meloni, D.; Monteleone, F.; Severi, M.; Traversi, R.; Udisti, R.

    2012-04-01

    Measurements of aerosol chemical composition made on the island of Lampedusa, south of the Sicily channel, during years 2004-2008, are used to identify the influence of heavy fuel oil (HFO) combustion emissions on aerosol particles in the Central Mediterranean. Aerosol samples influenced by HFO are characterized by elevated Ni and V soluble fraction (about 80% for aerosol from HFO combustion, versus about 40% for crustal particles), high V and Ni to Si ratios, and values of Vsol>6 ng m-3. Evidence of HFO combustion influence is found in 17% of the daily samples. Back trajectories analysis on the selected events show that air masses prevalently come from the Sicily channel region, where an intense ship traffic occurs. This behavior suggests that single fixed sources like refineries are not the main responsible for the elevated V and Ni events, which are probably mainly due to ships emissions. Vsol, Nisol, and non-sea salt SO42- (nssSO42-) show a marked seasonal behaviour, with an evident summer maximum. Such a pattern can be explained by several processes: (i) increased photochemical activity in summer, leading to a faster production of secondary aerosols, mainly nssSO42-, from the oxidation of SO2 (ii) stronger marine boundary layer (MBL) stability in summer, leading to higher concentration of emitted compounds in the lowest atmospheric layers. A very intense event in spring 2008 was studied in detail, also using size segregated chemical measurements. These data show that elements arising from heavy oil combustion (V, Ni, Al, Fe) are distributed in the sub-micrometric fraction of the aerosol, and the metals are present as free metals, carbonates, oxides hydrates or labile complex with organic ligands, so that they are dissolved in mild condition (HNO3, pH1.5). Data suggest a characteristic nssSO42-/V ratio in the range 200-400 for HFO combustion aerosols in summer at Lampedusa. By using the value of 200 a lower limit for the HFO contribution to total sulphates is

  8. Early diagenesis of mangrove leaves in a tropical estuary: Bulk chemical characterization using solid-state 13C NMR and elemental analyses

    NASA Astrophysics Data System (ADS)

    Benner, Ronald; Hatcher, Patrick G.; Hedges, John I.

    1990-07-01

    Changes in the chemical composition of mangrove ( Rhizophora mangle) leaves during decomposition in tropical estuarine waters were characterized using solid-state 13C nuclear magnetic resonance (NMR) and elemental (CHNO) analysis. Carbohydrates were the most abundant components of the leaves accounting for about 50 wt% of senescent tissues. Tannins were estimated to account for about 20 wt% of leaf tissues, and lipid components, cutin, and possibly other aliphatic biopolymers in leaf cuticles accounted for about 15 wt%. Carbohydrates were generally less resistant to decomposition than the other constituents and decreased in relative concentration during decomposition. Tannins were of intermediate resistance to decomposition and remained in fairly constant proportion during decomposition. Paraffinic components were very resistant to decomposition and increased in relative concentration as decomposition progressed. Lignin was a minor component of all leaf tissues. Standard methods for the colorimetric determination of tannins (Folin-Dennis reagent) and the gravimetric determination of lignin (Klason lignin) were highly inaccurate when applied to mangrove leaves. The N content of the leaves was particularly dynamic with values ranging from 1.27 wt% in green leaves to 0.65 wt% in senescent yellow leaves attached to trees. During decomposition in the water the N content initially decreased to 0.51 wt% due to leaching, but values steadily increased thereafter to 1.07 wt% in the most degraded leaf samples. The absolute mass of N in the leaves increased during decomposition indicating that N immobilization was occurring as decomposition progressed.

  9. Early diagenesis of mangrove leaves in a tropical estuary: Bulk chemical characterization using solid-state 13C NMR and elemental analyses

    USGS Publications Warehouse

    Benner, R.; Hatcher, P.G.; Hedges, J.I.

    1990-01-01

    Changes in the chemical composition of mangrove (Rhizophora mangle) leaves during decomposition in tropical estuarine waters were characterized using solid-state 13C nuclear magnetic resonance (NMR) and elemental (CHNO) analysis. Carbohydrates were the most abundant components of the leaves accounting for about 50 wt% of senescent tissues. Tannins were estimated to account for about 20 wt% of leaf tissues, and lipid components, cutin, and possibly other aliphatic biopolymers in leaf cuticles accounted for about 15 wt%. Carbohydrates were generally less resistant to decomposition than the other constituents and decreased in relative concentration during decomposition. Tannins were of intermediate resistance to decomposition and remained in fairly constant proportion during decomposition. Paraffinic components were very resistant to decomposition and increased in relative concentration as decomposition progressed. Lignin was a minor component of all leaf tissues. Standard methods for the colorimetric determination of tannins (Folin-Dennis reagent) and the gravimetric determination of lignin (Klason lignin) were highly inaccurate when applied to mangrove leaves. The N content of the leaves was particularly dynamic with values ranging from 1.27 wt% in green leaves to 0.65 wt% in senescent yellow leaves attached to trees. During decomposition in the water the N content initially decreased to 0.51 wt% due to leaching, but values steadily increased thereafter to 1.07 wt% in the most degraded leaf samples. The absolute mass of N in the leaves increased during decomposition indicating that N immobilization was occurring as decomposition progressed. ?? 1990.

  10. Detailed Chemical Composition of Condensed Tannins via Quantitative (31)P NMR and HSQC Analyses: Acacia catechu, Schinopsis balansae, and Acacia mearnsii.

    PubMed

    Crestini, Claudia; Lange, Heiko; Bianchetti, Giulia

    2016-09-23

    The chemical composition of Acacia catechu, Schinopsis balansae, and Acacia mearnsii proanthocyanidins has been determined using a novel analytical approach that rests on the concerted use of quantitative (31)P NMR and two-dimensional heteronuclear NMR spectroscopy. This approach has offered significant detailed information regarding the structure and purity of these complex and often elusive proanthocyanidins. More specifically, rings A, B, and C of their flavan-3-ol units show well-defined and resolved absorbance regions in both the quantitative (31)P NMR and HSQC spectra. By integrating each of these regions in the (31)P NMR spectra, it is possible to identify the oxygenation patterns of the flavan-3-ol units. At the same time it is possible to acquire a fingerprint of the proanthocyanidin sample and evaluate its purity via the HSQC information. This analytical approach is suitable for both the purified natural product proanthocyanidins and their commercial analogues. Overall, this effort demonstrates the power of the concerted use of these two NMR techniques for the structural elucidation of natural products containing labile hydroxy protons and a carbon framework that can be traced out via HSQC. PMID:27551744

  11. X-ray photoelectron spectroscopy analysis for the chemical impact of solvent addition rate on electromagnetic shielding effectiveness of HCl-doped polyaniline nanopowders

    SciTech Connect

    Tantawy, Hesham Ramzy; Aston, D. Eric; Kengne, Blaise-Alexis F.; McIlroy, David N.; Qiang, You; Nguyen, Tai; Heo, Deukhyoun

    2015-11-07

    An in-depth analysis of the chemical functionality in HCl-doped polyaniline (PANI) nanopowders is discussed through interpretations of x-ray photoelectron spectra. The distinctions between three PANI sample types, produced under varied synthesis conditions, are compared on the basis correlations between newly collected electron spectra for chemical analysis (or also x-ray photoelectron spectroscopy) and electromagnetic (EM) shielding effectiveness (SE) within two frequency bands (100–1500 MHz and ∼2–14 GHz). The findings are discussed with reference to previous data analysis of electrical conductivities and Raman and UV-vis spectra analyzed from replicates of the same PANI nanopowders, where only the 8–12 GHz range for SE was tested. They further corroborate previous results for limited-solvent conditions that enhance EM shielding. The three nanopowder types show distinctive differences in polaron, bipolaron, and polar lattice contributions. The collective findings describe the chemical connections between controlling and, most importantly, limiting the available solvent for polymerization with simultaneously doping and how it is that the newly developed solvent-limited approach for HCl-PANI nanopowders provides better shielding than traditionally solvent-rich methods by having more extended and perhaps even faster polaron delocalization than other PANI-based products. The maximum oxidation (50%) and doping (49%) levels obtained in the solvent-free nanopowders also produced the highest SE values of 37.3 ± 3.7 dB (MHz band) and 68.6 ± 4.6 dB (GHz band)

  12. ADDITIVITY ASSESSMENT OF TRIHALOMETHANE MIXTURES BY PROPORTIONAL RESPONSE ADDITION

    EPA Science Inventory

    If additivity is known or assumed, the toxicity of a chemical mixture may be predicted from the dose response curves of the individual chemicals comprising the mixture. As single chemical data are abundant and mixture data sparse, mixture risk methods that utilize single chemical...

  13. Serological, chemical, and structural analyses of the Escherichia coli cross-reactive capsular polysaccharides K13, K20, and K23.

    PubMed Central

    Vann, W F; Soderstrom, T; Egan, W; Tsui, F P; Schneerson, R; Orskov, I; Orskov, F

    1983-01-01

    The Escherichia coli K13, K20, and K23 capsular polysaccharide antigens are serologically related. All of these polysaccharides contain ribose and 2-keto-3-deoxyoctonate in equimolar quantities. The K13 and K20 polysaccharides are partially O-acetylated. A comparison of these polysaccharides after O-deacetylation, by nuclear magnetic resonance and permethylation analysis, showed that these polysaccharides contained the disaccharide repeat unit leads to)-beta-ribofuranosyl-(1 leads to 7)-beta-2-keto-3-deoxyoctonate. They differed in the presence and location of an acetyl moiety. The K13 polysaccharide was O-acetylated at C-4 of the 2-keto-3-deoxyoctonate. The K20 antigen was O-acetylated at C-5 of the ribose moiety. The K23 polymer was nonacetylated. The cross-reactivity of these antigens was demonstrated by tandem-crossed immunoelectrophoresis. Antibodies to K23 could be completely absorbed from OK K23 serum by K13, K20, and K23 antigenic extracts. The K13 and K20 antibodies could be completely absorbed from their respective antisera only by homologous antigenic extracts. Monoclonal antibodies were prepared against a protein conjugate of the K13 polysaccharide. Analyses of the reactions of these antibodies with the three polysaccharides suggest that the K13 polysaccharide has at least three antigenic sites, one of which is common to the K13, K20, and K23 polysaccharides. PMID:6187684

  14. [Effects of technological additives and heating range on some chemical and physical changes in canned meat. 2. Changes in redox potentials and selected quality characteristics].

    PubMed

    Wojciechowski, J; Pikul, J; Janitz, W

    1976-01-01

    The influence of technological additives and the range of heating on the redox potential, as well as on some quality features of canned meat was examined. The experiments showed, that the time of storage and the degree of heating of model preserves of meat influence on the redox potential. The technological additions as polyphosphates, ascorbic acid, gelatine and mixtures of these substances influence less on the redox potential. The analysis of each experimental factor showed, that on the secretion of meat juice occurring during can pasteurization or sterilization influence all experimental factors, as the kind of heating, the time of storage as well as the kind and the quantity of technological additives. The highest secretion of meat juice was found in cans with addition of ascorbic acid. Cans with addition of gelatine had the smallest content of jelly and consequently the lowest secretion of meat juice. It was also found a certain relation between the level of redox potential and the tested quality features of the model meat preserves.

  15. [Determination of the Plant Origin of Licorice Oil Extract, a Natural Food Additive, by Principal Component Analysis Based on Chemical Components].

    PubMed

    Tada, Atsuko; Ishizuki, Kyoko; Sugimoto, Naoki; Yoshimatsu, Kayo; Kawahara, Nobuo; Suematsu, Takako; Arifuku, Kazunori; Fukai, Toshio; Tamura, Yukiyoshi; Ohtsuki, Takashi; Tahara, Maiko; Yamazaki, Takeshi; Akiyama, Hiroshi

    2015-01-01

    "Licorice oil extract" (LOE) (antioxidant agent) is described in the notice of Japanese food additive regulations as a material obtained from the roots and/or rhizomes of Glycyrrhiza uralensis, G. inflata or G. glabra. In this study, we aimed to identify the original Glycyrrhiza species of eight food additive products using LC/MS. Glabridin, a characteristic compound in G. glabra, was specifically detected in seven products, and licochalcone A, a characteristic compound in G. inflata, was detected in one product. In addition, Principal Component Analysis (PCA) (a kind of multivariate analysis) using the data of LC/MS or (1)H-NMR analysis was performed. The data of thirty-one samples, including LOE products used as food additives, ethanol extracts of various Glycyrrhiza species and commercially available Glycyrrhiza species-derived products were assessed. Based on the PCA results, the majority of LOE products was confirmed to be derived from G. glabra. This study suggests that PCA using (1)H-NMR analysis data is a simple and useful method to identify the plant species of origin of natural food additive products. PMID:26537652

  16. [Determination of the Plant Origin of Licorice Oil Extract, a Natural Food Additive, by Principal Component Analysis Based on Chemical Components].

    PubMed

    Tada, Atsuko; Ishizuki, Kyoko; Sugimoto, Naoki; Yoshimatsu, Kayo; Kawahara, Nobuo; Suematsu, Takako; Arifuku, Kazunori; Fukai, Toshio; Tamura, Yukiyoshi; Ohtsuki, Takashi; Tahara, Maiko; Yamazaki, Takeshi; Akiyama, Hiroshi

    2015-01-01

    "Licorice oil extract" (LOE) (antioxidant agent) is described in the notice of Japanese food additive regulations as a material obtained from the roots and/or rhizomes of Glycyrrhiza uralensis, G. inflata or G. glabra. In this study, we aimed to identify the original Glycyrrhiza species of eight food additive products using LC/MS. Glabridin, a characteristic compound in G. glabra, was specifically detected in seven products, and licochalcone A, a characteristic compound in G. inflata, was detected in one product. In addition, Principal Component Analysis (PCA) (a kind of multivariate analysis) using the data of LC/MS or (1)H-NMR analysis was performed. The data of thirty-one samples, including LOE products used as food additives, ethanol extracts of various Glycyrrhiza species and commercially available Glycyrrhiza species-derived products were assessed. Based on the PCA results, the majority of LOE products was confirmed to be derived from G. glabra. This study suggests that PCA using (1)H-NMR analysis data is a simple and useful method to identify the plant species of origin of natural food additive products.

  17. Investigating the chemical changes of chlorogenic acids during coffee brewing: conjugate addition of water to the olefinic moiety of chlorogenic acids and their quinides.

    PubMed

    Matei, Marius Febi; Jaiswal, Rakesh; Kuhnert, Nikolai

    2012-12-12

    Coffee is one of the most popular and consumed beverages in the world and is associated with a series of benefits for human health. In this study we focus on the reactivity of chlorogenic acids, the most abundant secondary metabolites in coffee, during the coffee brewing process. We report on the hydroxylation of the chlorogenic acid cinnamoyl substituent by conjugate addition of water to form 3-hydroxydihydrocaffeic acid derivatives using a series of model compounds including monocaffeoyl and dicaffeoylquinic acids and quinic acid lactones. The regiochemistry of conjugate addition was established based on targeted tandem MS experiments. Following conjugate addition of water a reversible water elimination yielding cis-cinnamoyl derivatives accompanied by acyl migration products was observed in model systems. We also report the formation of all of these derivatives during the coffee brewing process.

  18. 1,4-Addition of bis(iodozincio)methane to α,β-unsaturated ketones: chemical and theoretical/computational studies.

    PubMed

    Sada, Mutsumi; Furuyama, Taniyuki; Komagawa, Shinsuke; Uchiyama, Masanobu; Matsubara, Seijiro

    2010-09-10

    1,4-Addition of bis(iodozincio)methane to simple α,β-unsaturated ketones does not proceed well; the reaction is slightly endothermic according to DFT calculations. In the presence of chlorotrimethylsilane, the reaction proceeded efficiently to afford a silyl enol ether of β-zinciomethyl ketone. The C--Zn bond of the silyl enol ether could be used in a cross-coupling reaction to form another C--C bond in a one-pot reaction. In contrast, 1,4-addition of the dizinc reagent to enones carrying an acyloxy group proceeded very efficiently without any additive. In this case, the product was a 1,3-diketone, which was generated in a novel tandem reaction. A theoretical/computational study indicates that the whole reaction pathway is exothermic, and that two zinc atoms of bis(iodozincio)methane accelerate each step cooperatively as effective Lewis acids. PMID:20645344

  19. Roles of pyrolysis on availability, species and distribution of Cu and Zn in the swine manure: chemical extractions and high-energy synchrotron analyses.

    PubMed

    Lin, Q; Liang, L; Wang, L H; Ni, Q L; Yang, K; Zhang, J; Chen, D L; Yang, J J; Shen, X D

    2013-11-01

    Animal manures generally contain high levels of heavy metals that may pose a significant threat to soil and groundwater qualities. Pyrolysis as means of reducing metal availability in such feed stocks is recently encouraged, but systematic studies are currently lacking. The aim of this study was to assess the impact of pyrolysis temperature on the availability of Cu and Zn by chemical extraction, to determine the speciation of Cu and Zn by synchrotron-based X-ray spectroscopy, and finally to investigate the phase distribution of metal species in the carbonaceous materials by combining acid-base extractions and absorption spectroscopy data. The results showed that both Cu and Zn in the swine manure were mainly bound to organic functional groups. Cu (II) reduction and Cu (I)-S complexes were observed during the pyrolysis process. Zn species resembling ZnAc2 was still dominant, being 60.8-69.2%, and ZnS increased by 6.6-21.8% in the carbonaceous materials. The distribution of Cu and Zn in the mineral, carbonized and non-carbonized organic phases varied greatly with the pyrolysis temperature. The higher the temperature, the more the metals existed in the mineral phase and carbonized organic phase. The decrease of EDTA extractable Cu and Zn with pyrolysis temperature was due to the increase of metals in the carbonized organic phase and mineral phase. It is suggested that pyrolysis at the relatively higher temperature is a better choice for metal-containing manure according to the metal speciation, solubility and availability. PMID:23972909

  20. Changes in lead and zinc lability during weathering-induced acidification of desert mine tailings: Coupling chemical and micro-scale analyses.

    PubMed

    Hayes, Sarah M; White, Scott A; Thompson, Thomas L; Maier, Raina M; Chorover, Jon

    2009-12-01

    Desert mine tailings may accumulate toxic metals in the near surface centimeters because of low water through-flux rates. Along with other constraints, metal toxicity precludes natural plant colonization even over decadal time scales. Since unconsolidated particles can be subjected to transport by wind and water erosion, potentially resulting in direct human and ecosystem exposure, there is a need to know how the lability and form of metals change in the tailings weathering environment. A combination of chemical extractions, X-ray diffraction, micro-X-ray fluorescence spectroscopy, and micro-Raman spectroscopy were employed to study Pb and Zn contamination in surficial arid mine tailings from the Arizona Klondyke State Superfund Site. Initial site characterization indicated a wide range in pH (2.5 to 8.0) in the surficial tailings pile. Ligand-promoted (DTPA) extractions, used to assess plant-available metal pools, showed decreasing available Zn and Mn with progressive tailings acidification. Aluminum shows the inverse trend, and Pb and Fe show more complex pH dependence. Since the tailings derive from a common source and parent mineralogy, it is presumed that variations in pH and "bioavailable" metal concentrations result from associated variation in particle-scale geochemistry. Four sub-samples, ranging in pH from 2.6 to 5.4, were subjected to further characterization to elucidate micro-scale controls on metal mobility. With acidification, total Pb (ranging from 5 - 13 g kg(-1)) was increasingly associated with Fe and S in plumbojarosite aggregates. For Zn, both total (0.4 - 6 g kg(-1)) and labile fractions decreased with decreasing pH. Zinc was found to be primarily associated with the secondary Mn phases manjiroite and chalcophanite. The results suggest that progressive tailings acidification diminishes the overall lability of the total Pb and Zn pools.

  1. Changes in lead and zinc lability during weathering-induced acidification of desert mine tailings: Coupling chemical and micro-scale analyses

    PubMed Central

    Hayes, Sarah M.; White, Scott A.; Thompson, Thomas L.; Maier, Raina M.; Chorover, Jon

    2009-01-01

    Desert mine tailings may accumulate toxic metals in the near surface centimeters because of low water through-flux rates. Along with other constraints, metal toxicity precludes natural plant colonization even over decadal time scales. Since unconsolidated particles can be subjected to transport by wind and water erosion, potentially resulting in direct human and ecosystem exposure, there is a need to know how the lability and form of metals change in the tailings weathering environment. A combination of chemical extractions, X-ray diffraction, micro-X-ray fluorescence spectroscopy, and micro-Raman spectroscopy were employed to study Pb and Zn contamination in surficial arid mine tailings from the Arizona Klondyke State Superfund Site. Initial site characterization indicated a wide range in pH (2.5 to 8.0) in the surficial tailings pile. Ligand-promoted (DTPA) extractions, used to assess plant-available metal pools, showed decreasing available Zn and Mn with progressive tailings acidification. Aluminum shows the inverse trend, and Pb and Fe show more complex pH dependence. Since the tailings derive from a common source and parent mineralogy, it is presumed that variations in pH and “bioavailable” metal concentrations result from associated variation in particle-scale geochemistry. Four sub-samples, ranging in pH from 2.6 to 5.4, were subjected to further characterization to elucidate micro-scale controls on metal mobility. With acidification, total Pb (ranging from 5 – 13 g kg−1) was increasingly associated with Fe and S in plumbojarosite aggregates. For Zn, both total (0.4 – 6 g kg−1) and labile fractions decreased with decreasing pH. Zinc was found to be primarily associated with the secondary Mn phases manjiroite and chalcophanite. The results suggest that progressive tailings acidification diminishes the overall lability of the total Pb and Zn pools. PMID:20161492

  2. Energy, Environmental, and Economic Analyses of Design Concepts for the Co-Production of Fuels and Chemicals with Electricity via Co-Gasification of Coal and Biomass

    SciTech Connect

    Eric Larson; Robert Williams; Thomas Kreutz; Ilkka Hannula; Andrea Lanzini; Guangjian Liu

    2012-03-11

    The overall objective of this project was to quantify the energy, environmental, and economic performance of industrial facilities that would coproduce electricity and transportation fuels or chemicals from a mixture of coal and biomass via co-gasification in a single pressurized, oxygen-blown, entrained-flow gasifier, with capture and storage of CO{sub 2} (CCS). The work sought to identify plant designs with promising (Nth plant) economics, superior environmental footprints, and the potential to be deployed at scale as a means for simultaneously achieving enhanced energy security and deep reductions in U.S. GHG emissions in the coming decades. Designs included systems using primarily already-commercialized component technologies, which may have the potential for near-term deployment at scale, as well as systems incorporating some advanced technologies at various stages of R&D. All of the coproduction designs have the common attribute of producing some electricity and also of capturing CO{sub 2} for storage. For each of the co-product pairs detailed process mass and energy simulations (using Aspen Plus software) were developed for a set of alternative process configurations, on the basis of which lifecycle greenhouse gas emissions, Nth plant economic performance, and other characteristics were evaluated for each configuration. In developing each set of process configurations, focused attention was given to understanding the influence of biomass input fraction and electricity output fraction. Self-consistent evaluations were also carried out for gasification-based reference systems producing only electricity from coal, including integrated gasification combined cycle (IGCC) and integrated gasification solid-oxide fuel cell (IGFC) systems. The reason biomass is considered as a co-feed with coal in cases when gasoline or olefins are co-produced with electricity is to help reduce lifecycle greenhouse gas (GHG) emissions for these systems. Storing biomass-derived CO

  3. Effects of chemical, biological, and physical aging as well as soil addition on the sorption of pyrene to activated carbon and biochar.

    PubMed

    Hale, Sarah E; Hanley, Kelly; Lehmann, Johannes; Zimmerman, Andrewr; Cornelissen, Gerard

    2011-12-15

    In this study, the suitability of biochar and activated carbon (AC) for contaminated soil remediation is investigated by determining the sorption of pyrene to both materials in the presence and absence of soil and before as well as after aging. Biochar and AC were aged either alone or mixed with soil via exposure to (a) nutrients and microorganisms (biological), (b) 60 and 110 °C (chemical), and (c) freeze-thaw cycles (physical). Before and after aging, the pH, elemental composition, cation exchange capacity (CEC), microporous SA, and sorption isotherms of pyrene were quantified. Aging at 110 °C altered the physicochemical properties of all materials to the greatest extent (for example, pH increased by up to three units and CEC by up to 50% for biochar). Logarithmic K(Fr) values ranged from 7.80 to 8.21 (ng kg(-1))(ng L(-1))(-nF) for AC and 5.22 to 6.21 (ng kg(-1))(ng L(-1))(-nF) for biochar after the various aging regimes. Grinding biochar to a smaller particle size did not significantly affect the sorption of d(10) pyrene, implying that sorption processes operate on the subparticle scale. Chemical aging decreased the sorption of pyrene to the greatest extent (up to 1.8 log unit for the biochar+soil). The sorption to AC was affected more by the presence of soil than the sorption to biochar was. Our results suggest that AC and biochar have a high sorption capacity for pyrene that is maintained both in the presence of soil and during harsh aging. Both materials could therefore be considered in contaminated land remediation.

  4. Mutagenic and chemical analyses provide new insight into enzyme activation and mechanism of the type 2 iron-sulfur l-serine dehydratase from Legionella pneumophila.

    PubMed

    Xu, Xiao Lan; Grant, Gregory A

    2016-04-15

    The crystal structure of the Type 2 l-serine dehydratase from Legionella pneumophila (lpLSD), revealed a "tail-in-mouth" configuration where the C-terminal residue acts as an intrinsic competitive inhibitor. This pre-catalytic structure undergoes an activation step prior to catalytic turnover. Mutagenic analysis of residues at or near the active site cleft is consistent with stabilization of substrate binding by many of the same residues that interact with the C-terminal cysteine and highlight the critical role of certain tail residues in activity. pH-rate profiles show that a residue with pK of 5.9 must be deprotonated and a residue with a pK of 8.5 must be protonated for activity. This supports an earlier suggestion that His 61 is the likely catalytic base. An additional residue with a pK of 8.5-9 increases cooperativity when it is deprotonated. This investigation also demonstrates that the Fe-S dehydratases convert the enamine/imine intermediates of the catalytic reaction to products on the enzyme prior to release. This is in contrast to pyridoxyl 5' phosphate based dehydratases that release an enamine/imine intermediate into solution, which then hydrolyzes to produce the ketoamine product.

  5. "Additive" cooperativity of hydrogen bonds in complexes of catechol with proton acceptors in the gas phase: FTIR spectroscopy and quantum chemical calculations.

    PubMed

    Varfolomeev, Mikhail A; Klimovitskii, Alexander E; Abaidullina, Dilyara I; Madzhidov, Timur I; Solomonov, Boris N

    2012-06-01

    Experimental study of hydrogen bond cooperativity in hetero-complexes in the gas phase was carried out by IR-spectroscopy method. Stretching vibration frequencies of O-H groups in phenol and catechol molecules as well as of their complexes with nitriles and ethers were determined in the gas phase using a specially designed cell. O-H groups experimental frequency shifts in the complexes of catechol induced by the formation of intermolecular hydrogen bonds are significantly higher than in the complexes of phenol due to the hydrogen bond cooperativity. It was shown that the cooperativity factors of hydrogen bonds in the complexes of catechol with nitriles and ethers in the gas phase are approximately the same. Quantum chemical calculations of the studied systems have been performed using density functional theory (DFT) methods. It was shown, that theoretically obtained cooperativity factors of hydrogen bonds in the complexes of catechol with proton acceptors are in good agreement with experimental values. Cooperative effects lead to a strengthening of intermolecular hydrogen bonds in the complexes of catechol on about 30%, despite the significant difference in the proton acceptor ability of the bases. The analysis within quantum theory of atoms in molecules was carried out for the explanation of this fact.

  6. The role of chemical additives to the phase change process of CaCl2.6H2O to optimize its performance as latent heat energy storage system

    NASA Astrophysics Data System (ADS)

    Sutjahja, I. M.; U, S. Rahayu A.; Kurniati, Nia; Pallitine, Ivyalentine D.; Kurnia, D.

    2016-08-01

    CaCl2.6H2O is one of salt hydrate based phase change material (PCM) which is suitable for room air-temperature stabilizer because it has the melting temperature just above the human comfort zone temperature (Tm ∼⃒ 29 oC) and a relatively large heat entalphy (AH ∼⃒ 190 kJ/kg). This paper reports the role of the type of chemical additives to PCM CaCl2.6H2O to the phase change process throughout the solidification process or heat release in order to optimize its performance as latent heat energy storage system. In this research we used several kinds of chemical additive, namely SrCl2.6H2O (1.0 wt%), BaCO3 (0.5 wt%), and K2CO3 (0.5 wt%). In terms of its latent time for phase change process the order the effectiveness of those chemical additives are reduced from SrCl2.6H2O, BaCO3and K2CO3. We found that this is also related to their role in suppression supercooling and phase separation effects which occurs during crystallization process of CaCl2.6H2O.

  7. Iodine and Selenium Biofortification with Additional Application of Salicylic Acid Affects Yield, Selected Molecular Parameters and Chemical Composition of Lettuce Plants (Lactuca sativa L. var. capitata)

    PubMed Central

    Smoleń, Sylwester; Kowalska, Iwona; Czernicka, Małgorzata; Halka, Mariya; Kęska, Kinga; Sady, Włodzimierz

    2016-01-01

    Iodine (I) and selenium (Se) are included in the group of beneficial elements. They both play important roles in humans and other animals, particularly in the regulation of thyroid functioning. A substantial percentage of people around the world suffer from health disorders related to the deficiency of these elements in the diet. Salicylic acid (SA) is a compound similar to phytohormones and is known to improve the efficiency of I biofortification of plants. The influence of SA on Se enrichment of plants has not, however, been recognized together with its effect on simultaneous application of I and Se to plants. Two-year studies (2014–2015) were conducted in a greenhouse with hydroponic cultivation of lettuce in an NFT (nutrient film technique) system. They included the application of I (as KIO3), Se (as Na2SeO3) and SA into the nutrient solution. KIO3 was used at a dose of 5 mg I⋅dm-3 (i.e., 39.4 μM I), while Na2SeO3 was 0.5 mg Se⋅dm-3 (i.e., 6.3 μM Se). SA was introduced at three doses: 0.1, 1.0, and 10.0 mg⋅dm-3 nutrient solutions, equivalent to 0.724, 7.24, and 72.4 μM SA, respectively. The tested combinations were as follows: (1) control, (2) I + Se, (3) I + Se + 0.1 mg SA⋅dm-3, (4) I + Se + 1.0 mg SA⋅dm-3 and (5) I + Se + 10.0 mg SA⋅dm-3. The applied treatments had no significant impact on lettuce biomass (leaves and roots). Depending on the dose, a diverse influence of SA was noted with respect to the efficiency of I and Se biofortification; chemical composition of leaves; and mineral nutrition of lettuce plants, including the content of macro- and microelements and selenocysteine methyltransferase (SMT) gene expression. SA application at all tested doses comparably increased the level of selenomethionine (SeMet) and decreased the content of SA in leaves. PMID:27803709

  8. Advanced glycation end products, physico-chemical and sensory characteristics of cooked lamb loins affected by cooking method and addition of flavour precursors.

    PubMed

    Roldan, Mar; Loebner, Jürgen; Degen, Julia; Henle, Thomas; Antequera, Teresa; Ruiz-Carrascal, Jorge

    2015-02-01

    The influence of the addition of a flavour enhancer solution (FES) (d-glucose, d-ribose, l-cysteine and thiamin) and of sous-vide cooking or roasting on moisture, cooking loss, instrumental colour, sensory characteristics and formation of Maillard reaction (MR) compounds in lamb loins was studied. FES reduced cooking loss and increased water content in sous-vide samples. FES and cooking method showed a marked effect on browning development, both on the meat surface and within. FES led to tougher and chewier texture in sous-vide cooked lamb, and enhanced flavour scores of sous-vide samples more markedly than in roasted ones. FES added meat showed higher contents of furosine; 1,2-dicarbonyl compounds and 5-hydroxymethylfurfural did not reach detectable levels. N-ε-carboxymethyllysine amounts were rather low and not influenced by the studied factors. Cooked meat seems to be a minor dietary source of MR products, regardless the presence of reducing sugars and the cooking method. PMID:25172739

  9. Advanced glycation end products, physico-chemical and sensory characteristics of cooked lamb loins affected by cooking method and addition of flavour precursors.

    PubMed

    Roldan, Mar; Loebner, Jürgen; Degen, Julia; Henle, Thomas; Antequera, Teresa; Ruiz-Carrascal, Jorge

    2015-02-01

    The influence of the addition of a flavour enhancer solution (FES) (d-glucose, d-ribose, l-cysteine and thiamin) and of sous-vide cooking or roasting on moisture, cooking loss, instrumental colour, sensory characteristics and formation of Maillard reaction (MR) compounds in lamb loins was studied. FES reduced cooking loss and increased water content in sous-vide samples. FES and cooking method showed a marked effect on browning development, both on the meat surface and within. FES led to tougher and chewier texture in sous-vide cooked lamb, and enhanced flavour scores of sous-vide samples more markedly than in roasted ones. FES added meat showed higher contents of furosine; 1,2-dicarbonyl compounds and 5-hydroxymethylfurfural did not reach detectable levels. N-ε-carboxymethyllysine amounts were rather low and not influenced by the studied factors. Cooked meat seems to be a minor dietary source of MR products, regardless the presence of reducing sugars and the cooking method.

  10. SNS shielding analyses overview

    SciTech Connect

    Popova, Irina; Gallmeier, Franz; Iverson, Erik B; Lu, Wei; Remec, Igor

    2015-01-01

    This paper gives an overview on on-going shielding analyses for Spallation Neutron Source. Presently, the most of the shielding work is concentrated on the beam lines and instrument enclosures to prepare for commissioning, save operation and adequate radiation background in the future. There is on-going work for the accelerator facility. This includes radiation-protection analyses for radiation monitors placement, designing shielding for additional facilities to test accelerator structures, redesigning some parts of the facility, and designing test facilities to the main accelerator structure for component testing. Neutronics analyses are required as well to support spent structure management, including waste characterisation analyses, choice of proper transport/storage package and shielding enhancement for the package if required.

  11. A chemical kinetic model for NO sub x removal in an aqueous scrubber system using the additive Fe(II)ter dot EDTA

    SciTech Connect

    Mendelsohn, M.H.; Livengood, C.D.

    1992-01-01

    Addition of the metal chelate, ferrous{center dot} ethylenediaminetetraacetate anion (Fe(II){center dot}EDTA{sup 2{minus}}), has been shown to increase the amount of gaseous nitrogen oxides absorbed from a gas stream containing sulfur dioxide, where an aqueous scrubbing process is used to treat the gas. Recently, we published data on improved systems for NO{sub x} removal that incorporate an antioxidant and/or reducing agent (A/R) in the process along with the Fe(H){center dot}EDTA. The purpose of the A/R is to maintain the highest possible concentration of iron in the +2 form. The major mechanism for NO removal is believed to be the equilibrium reaction of Fe(II){center dot}EDTA with dissolved NO to form a Fe(II){center dot}EDTA{center dot}NO complex. It has been shown that both sulfite and bisulfite anions can react with Fe(II){center dot}EDTA{center dot}NO to regenerate Fe(II){center dot}EDTA and other products. In a complex system, other oxidation and reduction mechanisms are also possible. We have chosen, therefore, to approach this problem empirically by fitting our experimental data to a model containing at most three kinetic terms, chosen from among the following: a baseline removal rate, which is equivalent to the rate of reaction of Fe(II){center dot}EDTA with nitric oxide; a regeneration rate, which is equivalent to decomposition of the Fe(II){center dot}EDTA{center dot}NO complex to Fe(II){center dot}EDTA; an oxidation rate, which is a combined rate for all possible oxidation reactions involving Fe(II){center dot}EDTA; and a reduction rate, which is a combined rate for all possible reduction reactions involving ferric-EDTA in the system.

  12. Evaluation of food additives as alternative or complementary chemicals to conventional fungicides for the control of major postharvest diseases of stone fruit.

    PubMed

    Palou, Lluis; Smilanick, Joseph L; Crisosto, Carlos H

    2009-05-01

    To evaluate potential alternatives to conventional fungicides to control decay, more than 20 food additives and generally regarded as safe compounds were tested at three concentrations in in vivo primary screenings with several cultivars of California peaches, nectarines, and plums that had been artificially inoculated with seven major postharvest pathogens: Monilinia fructicola, Botrytis cinerea, Geotrichum candidum, Alternaria alternata, Penicillium expansum, Mucor piriformis, and Rhizopus stolonifer. Overall, the best compounds were 200 mM potassium sorbate (PS), 200 mM sodium benzoate (SB), 200 mM sodium sorbate, 100 mM 2-deoxy-D-glucose, 400 mM sodium carbonate, and 250 mM potassium carbonate. Sodium and ammonium molybdates, acid lactic, and hydrogen peroxide were somewhat effective but were phytotoxic to fruit skin tissues. However, the best compounds lacked effectiveness and persistence when tested against brown rot in small-scale trials of 60-s dips in aqueous solutions at ambient temperatures; PS and SB reduced brown rot incidence by less than 40%. Rinsing treated fruit with tap water reduced the efficacy of the compounds by up to 30%. In contrast, heating the solutions to 55 or 60 degrees C significantly increased treatment efficacy. Brown rot incidence and severity were reduced by 35 and 25%, respectively, on PS-treated peaches after 7 days of incubation at 20 degrees C. However, treatment efficacy was not superior to that with water alone at these temperatures. In semicommercial trials, mixtures of fludioxonil with PS, SB, or 2-deoxy-D-glucose applied as fruit coatings on a packing line were not synergistic in their effect on brown rot, gray mold, and sour rot.

  13. A chemical kinetic model for NO{sub x} removal in an aqueous scrubber system using the additive Fe[II]{center_dot}EDTA

    SciTech Connect

    Mendelsohn, M.H.; Livengood, C.D.

    1992-09-01

    Addition of the metal chelate, ferrous{center_dot} ethylenediaminetetraacetate anion (Fe[II]{center_dot}EDTA{sup 2{minus}}), has been shown to increase the amount of gaseous nitrogen oxides absorbed from a gas stream containing sulfur dioxide, where an aqueous scrubbing process is used to treat the gas. Recently, we published data on improved systems for NO{sub x} removal that incorporate an antioxidant and/or reducing agent (A/R) in the process along with the Fe[H]{center_dot}EDTA. The purpose of the A/R is to maintain the highest possible concentration of iron in the +2 form. The major mechanism for NO removal is believed to be the equilibrium reaction of Fe[II]{center_dot}EDTA with dissolved NO to form a Fe[II]{center_dot}EDTA{center_dot}NO complex. It has been shown that both sulfite and bisulfite anions can react with Fe[II]{center_dot}EDTA{center_dot}NO to regenerate Fe[II]{center_dot}EDTA and other products. In a complex system, other oxidation and reduction mechanisms are also possible. We have chosen, therefore, to approach this problem empirically by fitting our experimental data to a model containing at most three kinetic terms, chosen from among the following: a baseline removal rate, which is equivalent to the rate of reaction of Fe[II]{center_dot}EDTA with nitric oxide; a regeneration rate, which is equivalent to decomposition of the Fe[II]{center_dot}EDTA{center_dot}NO complex to Fe[II]{center_dot}EDTA; an oxidation rate, which is a combined rate for all possible oxidation reactions involving Fe[II]{center_dot}EDTA; and a reduction rate, which is a combined rate for all possible reduction reactions involving ferric-EDTA in the system.

  14. Lidar Analyses

    NASA Technical Reports Server (NTRS)

    Spiers, Gary D.

    1995-01-01

    A brief description of enhancements made to the NASA MSFC coherent lidar model is provided. Notable improvements are the addition of routines to automatically determine the 3 dB misalignment loss angle and the backscatter value at which the probability of a good estimate (for a maximum likelihood estimator) falls to 50%. The ability to automatically generate energy/aperture parametrization (EAP) plots which include the effects of angular misalignment has been added. These EAP plots make it very easy to see that for any practical system where there is some degree of misalignment then there is an optimum telescope diameter for which the laser pulse energy required to achieve a particular sensitivity is minimized. Increasing the telescope diameter above this will result in a reduction of sensitivity. These parameterizations also clearly show that the alignment tolerances at shorter wavelengths are much stricter than those at longer wavelengths. A brief outline of the NASA MSFC AEOLUS program is given and a summary of the lidar designs considered during the program is presented. A discussion of some of the design trades is performed both in the text and in a conference publication attached as an appendix.

  15. Analysing small insect glands with UV-LDI MS: high-resolution spatial analysis reveals the chemical composition and use of the osmeterium secretion in Themira superba (Sepsidae: Diptera).

    PubMed

    Araujo, D P; Tuan, M J M; Yew, J Y; Meier, R

    2014-08-01

    For many insect species, pheromones are important communication tools, but chemical analysis and experimental study can be technically challenging because they require the detection and handling of complex chemicals in small quantities. One drawback of traditional mass spectrometry methods such as gas chromatography mass spectrometry is that whole-body extractions from one to several hundred individuals are required, with the consequence that intra- and interindividual differences cannot be detected. Here, we used the recently introduced UV-LDI MS (ultraviolet laser desorption/ionization mass spectrometry) to profile the 'osmeterium' of the sepsid fly Themira superba that is located on the edge of the hind tibia of males. Based on analyses of individual legs, we established that the gland produced a secretion that consisted of oxygenated hydrocarbons and putative isoprenoids. The secretion was first detected 24 h after eclosion, and its transfer to the wings of females during mating was demonstrated using UV-LDI MS. We then tested whether the secretion had an anti-aphrodisiac function, but experimental transfer of the secretion to virgin females did not affect mating success or copulation duration. Throughout the study, UV-LDI MS proved invaluable, because it allowed tracking the natural and experimental transfer of small quantities of pheromones to specific body parts of small flies.

  16. Effect of Rashba and Dresselhaus interactions on the energy spectrum, chemical potential, addition energy and spin-splitting in a many-electron parabolic GaAs quantum dot in a magnetic field

    NASA Astrophysics Data System (ADS)

    Kumar, D. Sanjeev; Mukhopadhyay, Soma; Chatterjee, Ashok

    2016-11-01

    The effect of electron-electron interaction and the Rashba and Dresselhaus spin-orbit interactions on the electronic properties of a many-electron system in a parabolically confined quantum dot placed in an external magnetic field is studied. With a simple and physically reasonable model potential for electron-electron interaction term, the problem is solved exactly to second-order in the spin-orbit coupling constants to obtain the energy spectrum, the chemical potential, addition energy and the spin-splitting energy.

  17. Phosphazene additives

    DOEpatents

    Harrup, Mason K; Rollins, Harry W

    2013-11-26

    An additive comprising a phosphazene compound that has at least two reactive functional groups and at least one capping functional group bonded to phosphorus atoms of the phosphazene compound. One of the at least two reactive functional groups is configured to react with cellulose and the other of the at least two reactive functional groups is configured to react with a resin, such as an amine resin of a polycarboxylic acid resin. The at least one capping functional group is selected from the group consisting of a short chain ether group, an alkoxy group, or an aryloxy group. Also disclosed are an additive-resin admixture, a method of treating a wood product, and a wood product.

  18. Potlining Additives

    SciTech Connect

    Rudolf Keller

    2004-08-10

    In this project, a concept to improve the performance of aluminum production cells by introducing potlining additives was examined and tested. Boron oxide was added to cathode blocks, and titanium was dissolved in the metal pool; this resulted in the formation of titanium diboride and caused the molten aluminum to wet the carbonaceous cathode surface. Such wetting reportedly leads to operational improvements and extended cell life. In addition, boron oxide suppresses cyanide formation. This final report presents and discusses the results of this project. Substantial economic benefits for the practical implementation of the technology are projected, especially for modern cells with graphitized blocks. For example, with an energy savings of about 5% and an increase in pot life from 1500 to 2500 days, a cost savings of $ 0.023 per pound of aluminum produced is projected for a 200 kA pot.

  19. Epidemiology of Type 1 Diabetes Mellitus in Korea through an Investigation of the National Registration Project of Type 1 Diabetes for the Reimbursement of Glucometer Strips with Additional Analyses Using Claims Data

    PubMed Central

    Song, Sun Ok; Nam, Joo Young; Park, Kyeong Hye; Yoon, Ji-Hae; Son, Kyung-Mi; Ko, Young; Lim, Dong-Ha

    2016-01-01

    Background The aim of this study was to estimate the prevalence and incidence of type 1 diabetes mellitus (T1DM) in Korea. In addition, we planned to do a performance analysis of the Registration Project of Type 1 diabetes for the reimbursement of consumable materials. Methods To obtain nationwide data on the incidence and prevalence of T1DM, we extracted claims data from July 2011 to August 2013 from the Registration Project of Type 1 diabetes on the reimbursement of consumable materials in the National Health Insurance (NHI) Database. For a more detailed analysis of the T1DM population in Korea, stratification by gender, age, and area was performed, and prevalence and incidence were calculated. Results Of the 8,256 subjects enrolled over the 26 months, the male to female ratio was 1 to 1.12, the median age was 37.1 years, and an average of 136 new T1DM patients were registered to the T1DM registry each month, resulting in 1,632 newly diagnosed T1DM patients each year. We found that the incidence rate of new T1DM cases was 3.28 per 100,000 people. The average proportion of T1DM patients compared with each region's population was 0.0125%. The total number of insurance subscribers under the universal compulsory NHI in Korea was 49,662,097, and the total number of diabetes patients, excluding duplication, was 3,762,332. Conclusion The prevalence of T1DM over the course of the study was approximately 0.017% to 0.021% of the entire population of Korea, and the annual incidence of T1DM was 3.28:100,000 overall and 3.25:100,000 for Koreans under 20 years old. PMID:26912154

  20. Surface molecular imprinting onto fluorescein-coated magnetic nanoparticlesvia reversible addition fragmentation chain transfer polymerization: A facile three-in-one system for recognition and separation of endocrine disrupting chemicals

    NASA Astrophysics Data System (ADS)

    Li, Ying; Dong, Cunku; Chu, Jia; Qi, Jingyao; Li, Xin

    2011-01-01

    In this study, we present a general protocol for the making of surface-imprinted magnetic fluorescence beads viareversible addition-fragmentation chain transfer polymerization. The resulting composites were characterized by X-ray diffraction analysis, transmission electron microscopy, scanning electron microscopy, fluorescence spectroscopy, Fourier transform infrared spectroscopy, and energy dispersive spectroscopy. The as-synthesized beads exhibited homogeneous polymer films (thickness of about 5.7 nm), spherical shape, high fluorescence intensity and magnetic property (Magnetization (Ms) = 3.67 emu g-1). The hybrids bind the original template 17β-estradiol with an appreciable selectivity over structurally related compounds. In addition, the resulting hybrids performed without obvious deterioration after five repeated cycles. This study therefore demonstrates the potential of molecularly imprinted polymers for the recognition and separation of endocrine disrupting chemicals.In this study, we present a general protocol for the making of surface-imprinted magnetic fluorescence beads viareversible addition-fragmentation chain transfer polymerization. The resulting composites were characterized by X-ray diffraction analysis, transmission electron microscopy, scanning electron microscopy, fluorescence spectroscopy, Fourier transform infrared spectroscopy, and energy dispersive spectroscopy. The as-synthesized beads exhibited homogeneous polymer films (thickness of about 5.7 nm), spherical shape, high fluorescence intensity and magnetic property (Magnetization (Ms) = 3.67 emu g-1). The hybrids bind the original template 17β-estradiol with an appreciable selectivity over structurally related compounds. In addition, the resulting hybrids performed without obvious deterioration after five repeated cycles. This study therefore demonstrates the potential of molecularly imprinted polymers for the recognition and separation of endocrine disrupting chemicals. Electronic

  1. Determination of the Pb, Cr, and Cd distribution patterns with various chlorine additives in the bottom ashes of a low-temperature two-stage fluidized bed incinerator by chemical sequential extraction.

    PubMed

    Peng, Tzu-Huan; Lin, Chiou-Liang; Wey, Ming-Yen

    2015-09-15

    A novel low-temperature two-stage fluidized bed (LTTSFB) incinerator has been successfully developed to control heavy-metal emissions during municipal solid waste (MSW) treatment. However, the characteristics of the residual metal patterns during this process are still unclear. The aim of this study was to investigate the metal patterns in the different partitions of the LTTSFB bottom ash by chemical sequential extraction. Artificial waste was used to simulate the MSW. Different parameters including the first-stage temperature, chloride additives, and operating gas velocity were also considered. Results indicated that during the low-temperature treatment process, a high metal mobility phase exists in the first-stage sand bed. The main patterns of Cd, Pb, and Cr observed were the water-soluble, exchangeable, and residual forms, respectively. With the different Cl additives, the results showed that polyvinyl chloride addition increased metal mobility in the LTTSFB bottom ash, while, sodium chloride addition may have reduced metal mobility due to the formation of eutectic material. The second-stage sand bed was found to have a lower risk of metal leaching. The results also suggested that, the residual ashes produced by the LTTSFB system must be taken into consideration given their high metal mobility. PMID:25885167

  2. Chemical peeling.

    PubMed

    Forte, R; Hack, J; Jackson, I T

    1993-01-01

    This article explores the wide range of chemical facial peels, which include phenol, trichloroacetic acid, and alpha-hydroxy acids. The application of these substances will be described in addition to the contraindications to this type of treatment.

  3. Unnecessary Chemicals

    ERIC Educational Resources Information Center

    Johnson, Anita

    1978-01-01

    Discusses the health hazards resulting from chemical additions of many common products such as cough syrups, food dyes, and cosmetics. Steps being taken to protect consumers from these health hazards are included. (MDR)

  4. Information Omitted From Analyses.

    PubMed

    2015-08-01

    In the Original Article titled “Higher- Order Genetic and Environmental Structure of Prevalent Forms of Child and Adolescent Psychopathology” published in the February 2011 issue of JAMA Psychiatry (then Archives of General Psychiatry) (2011;68[2]:181-189), there were 2 errors. Although the article stated that the dimensions of psychopathology were measured using parent informants for inattention, hyperactivity-impulsivity, and oppositional defiant disorder, and a combination of parent and youth informants for conduct disorder, major depression, generalized anxiety disorder, separation anxiety disorder, social phobia, specific phobia, agoraphobia, and obsessive-compulsive disorder, all dimensional scores used in the reported analyses were actually based on parent reports of symptoms; youth reports were not used. In addition, whereas the article stated that each symptom dimension was residualized on age, sex, age-squared, and age by sex, the dimensions actually were only residualized on age, sex, and age-squared. All analyses were repeated using parent informants for inattention, hyperactivity-impulsivity, and oppositional defiant disorder, and a combination of parent and youth informants for conduct disorder,major depression, generalized anxiety disorder, separation anxiety disorder, social phobia, specific phobia, agoraphobia, and obsessive-compulsive disorder; these dimensional scores were residualized on age, age-squared, sex, sex by age, and sex by age-squared. The results of the new analyses were qualitatively the same as those reported in the article, with no substantial changes in conclusions. The only notable small difference was that major depression and generalized anxiety disorder dimensions had small but significant loadings on the internalizing factor in addition to their substantial loadings on the general factor in the analyses of both genetic and non-shared covariances in the selected models in the new analyses. Corrections were made to the

  5. [Detection of food additives by enzyme immunoassay].

    PubMed

    Yoshida, A; Takagaki, Y

    1995-09-01

    The analysis of synthesized food additives is generally performed by chromatography or spectrophotometry. However, the analytical procedures for natural food additives have been little reported so far because they are difficult to analyse chemically. We have attempted to apply enzyme immunoassay (EIA) to the analysis of natural food additives. Hen egg white lysozyme, as a food preservative, was determined by the competitive EIA, using mouse anti-HEL ascites. Carminic acid (CA), which is the main component of cochineal color, was determined by the competitive EIA, using monoclonal anti-CA antibody. Phycocyanin, which is the main component of spirulina color, was determined by the avidin-biotin sandwich EIA, using double monoclonal anti-phycocyanin antibodies. PMID:7474399

  6. Microwave dielectric properties and chemical compatibility with silver electrode of Li2TiO3 ceramic with Li2O-ZnO-B2O3 glass additive

    NASA Astrophysics Data System (ADS)

    Sayyadi-Shahraki, A.; Taheri-Nassaj, E.; Hassanzadeh-Tabrizi, S. A.; Barzegar-Bafrooei, H.

    2015-01-01

    The effects of Li2O-ZnO-B2O3 (LZB) glass additive on the sintering behavior, phase composition, microstructure and microwave dielectric properties of Li2TiO3 (LT) ceramics have been investigated. The addition of a small amount of LZB glass can reduce the sintering temperature of LT ceramics from 1150 °C to 900 °C without obvious degradation of the microwave dielectric properties. Only a single-phase Li2TiO3 is formed in LT ceramic with LZB glass addition sintered at 900 °C for 2 h. Typically, the 2.5 wt% LZB glass-added LT ceramic sintered at 900 °C for 2 h can reach a maximum relative density of 94.8% of the theoretical density and exhibits good microwave dielectric properties of εr=22.9, Qf=59,600 GHz and τf=+23.7 ppm/°C. The XRD, SEM and EDX analyses showed that the ceramic can be co-fired well with Ag electrode, which may be applied for LTCC application.

  7. ISR meets SAR outside: additive action of the endophyte Bacillus pumilus INR7 and the chemical inducer, benzothiadiazole, on induced resistance against bacterial spot in field-grown pepper

    PubMed Central

    Yi, Hwe-Su; Yang, Jung Wook; Ryu, Choong-Min

    2013-01-01

    Induced resistance has been recognized as an attractive tool for plant disease management in modern agriculture. During the last two decades, studies on chemically- and biologically elicited induced resistance have revealed previously unknown features of the plant defense response including defense priming. As a biological trigger for induced resistance, plant growth-promoting rhizobacteria (PGPR) are a group of root-associated bacteria that can reduce plant disease severity and incidence, and augment plant growth and yield under greenhouse and field conditions. We evaluated the potential of an endophytic PGPR, Bacillus pumilus INR7, to induce systemic resistance against bacterial spot caused by Xanthomonas axonopodis pv. vesicatoria in pepper. Trials in the greenhouse showed significantly less symptom development in pepper plants inoculated with strain INR7 compared to a water treatment. Furthermore, a single dipping treatment with INR7 before transplantation of pepper plants into the field elicited an induced systemic resistance response against bacterial spot caused by artificially infiltration of X. axonopodis pv. vesicatoria and even against naturally occurring bacterial spot disease. We identified an additive effect on induced resistance after administration of a combination treatment composed of strain INR7 with a chemical inducer, benzothiadiazole (BTH) in the field. The combination treatment stimulated expression of pepper defense marker genes CaPR1, CaTin1, and CaPR4 to a greater extent than did treatment with either agent alone. Similar experiments conducted with tobacco revealed no additive effects under field conditions. Interestingly, co-application of plants with INR7 lifted the growth repressing effect of BTH. Application of BTH onto pepper and tobacco did not affect rhizosphere colonization but supported a higher population density inside plant roots when compared to water-treated control plants. Our results indicate that PGPR can be used in

  8. ISR meets SAR outside: additive action of the endophyte Bacillus pumilus INR7 and the chemical inducer, benzothiadiazole, on induced resistance against bacterial spot in field-grown pepper.

    PubMed

    Yi, Hwe-Su; Yang, Jung Wook; Ryu, Choong-Min

    2013-01-01

    Induced resistance has been recognized as an attractive tool for plant disease management in modern agriculture. During the last two decades, studies on chemically- and biologically elicited induced resistance have revealed previously unknown features of the plant defense response including defense priming. As a biological trigger for induced resistance, plant growth-promoting rhizobacteria (PGPR) are a group of root-associated bacteria that can reduce plant disease severity and incidence, and augment plant growth and yield under greenhouse and field conditions. We evaluated the potential of an endophytic PGPR, Bacillus pumilus INR7, to induce systemic resistance against bacterial spot caused by Xanthomonas axonopodis pv. vesicatoria in pepper. Trials in the greenhouse showed significantly less symptom development in pepper plants inoculated with strain INR7 compared to a water treatment. Furthermore, a single dipping treatment with INR7 before transplantation of pepper plants into the field elicited an induced systemic resistance response against bacterial spot caused by artificially infiltration of X. axonopodis pv. vesicatoria and even against naturally occurring bacterial spot disease. We identified an additive effect on induced resistance after administration of a combination treatment composed of strain INR7 with a chemical inducer, benzothiadiazole (BTH) in the field. The combination treatment stimulated expression of pepper defense marker genes CaPR1, CaTin1, and CaPR4 to a greater extent than did treatment with either agent alone. Similar experiments conducted with tobacco revealed no additive effects under field conditions. Interestingly, co-application of plants with INR7 lifted the growth repressing effect of BTH. Application of BTH onto pepper and tobacco did not affect rhizosphere colonization but supported a higher population density inside plant roots when compared to water-treated control plants. Our results indicate that PGPR can be used in

  9. Chemical analysis of some standard carbonate rocks

    USGS Publications Warehouse

    Galle, O.K.

    1969-01-01

    Twenty limestone, dolomite and limestone-dolomite blends were analyzed. The samples, which are available from the G. Fredrick Smith Chemical Company of Columbus, Ohio, were issued with an analysis certificate listing values for SiO2, Fe2O3, CaO and MgO. Additional analyses are reported and results compared with certificate values. ?? 1969.

  10. Phenylethynyl Containing Reactive Additives

    NASA Technical Reports Server (NTRS)

    Connell, John W. (Inventor); Smith, Joseph G., Jr. (Inventor); Hergenrother, Paul M. (Inventor)

    2002-01-01

    Phenylethynyl containing reactive additives were prepared from aromatic diamine, containing phenylethvnvl groups and various ratios of phthalic anhydride and 4-phenylethynviphthalic anhydride in glacial acetic acid to form the imide in one step or in N-methyl-2-pvrrolidinone to form the amide acid intermediate. The reactive additives were mixed in various amounts (10% to 90%) with oligomers containing either terminal or pendent phenylethynyl groups (or both) to reduce the melt viscosity and thereby enhance processability. Upon thermal cure, the additives react and become chemically incorporated into the matrix and effect an increase in crosslink density relative to that of the host resin. This resultant increase in crosslink density has advantageous consequences on the cured resin properties such as higher glass transition temperature and higher modulus as compared to that of the host resin.

  11. Optical properties and chemical composition analyses of mixed rare earth oxyorthosilicate (R2SiO5, R=La, Gd and Y) doped Dy3+ phosphors prepared by urea-assisted solution combustion method

    NASA Astrophysics Data System (ADS)

    Ogugua, S. N.; Shaat, S. K. K.; Swart, H. C.; Ntwaeaborwa, O. M.

    2015-08-01

    Dysprosium (Dy3+) doped lanthanum gadolinium oxyorthosilicate (LaGdSiO5), lanthanum yttrium oxyorthosilicate (LaYSiO5) and gadolinium yttrium oxyorthosilicate (GdYSiO5) phosphors (in powder form) were synthesized by urea-assisted combustion method. The X-ray diffractometer analysis confirmed that the LaGdSiO5, LaYSiO5 and GdYSiO5 crystalized in monoclinic phases. The chemical composition of the phosphors was analyzed by measuring the atomic and molecular ionic species using the time of flight secondary ion mass spectroscopy (ToF SIMS). In addition, ToF SIMS imaging technique was used to determine the distribution of the Dy3+ dopant ions on the surface on the phosphors. The average crystallite sizes and lattice strains of the phosphor were increased by Dy3+ doping. The field emission scanning electron microscope images showed that the powders were made up of an agglomeration of particles with no regular shape. The photoluminescence data showed narrow line emission peaks at the wavelengths of 485 nm (minor emission) and 573 nm (major emission) associated with the f→f transitions of Dy3+. The photoluminescence (PL) measurements showed that the emission peak of LaGdSiO5:Dy3+ was ~3× more intense than those of LaYSiO5:Dy3+ and GdYSiO5:Dy3+ when excited using monochromatic xenon lamp with a wavelength of 241 nm. However, when the powders were excited using a 325 nm He-Cd laser, the highest PL emission intensity was observed from GdYSiO5:Dy3+.

  12. Chemical Sensing for Buried Landmines - Fundamental Processes Influencing Trace Chemical Detection

    SciTech Connect

    PHELAN, JAMES M.

    2002-05-01

    Mine detection dogs have a demonstrated capability to locate hidden objects by trace chemical detection. Because of this capability, demining activities frequently employ mine detection dogs to locate individual buried landmines or for area reduction. The conditions appropriate for use of mine detection dogs are only beginning to emerge through diligent research that combines dog selection/training, the environmental conditions that impact landmine signature chemical vapors, and vapor sensing performance capability and reliability. This report seeks to address the fundamental soil-chemical interactions, driven by local weather history, that influence the availability of chemical for trace chemical detection. The processes evaluated include: landmine chemical emissions to the soil, chemical distribution in soils, chemical degradation in soils, and weather and chemical transport in soils. Simulation modeling is presented as a method to evaluate the complex interdependencies among these various processes and to establish conditions appropriate for trace chemical detection. Results from chemical analyses on soil samples obtained adjacent to landmines are presented and demonstrate the ultra-trace nature of these residues. Lastly, initial measurements of the vapor sensing performance of mine detection dogs demonstrates the extreme sensitivity of dogs in sensing landmine signature chemicals; however, reliability at these ultra-trace vapor concentrations still needs to be determined. Through this compilation, additional work is suggested that will fill in data gaps to improve the utility of trace chemical detection.

  13. [Patch-testing methods: additional specialised or additional series].

    PubMed

    Cleenewerck, M-B

    2009-01-01

    The tests in the European standard battery must occasionally be supplemented by specialised or additional batteries, particularly where the contact allergy is thought to be of occupational origin. These additional batteries cover all allergens associated with various professional activities (hairdressing, baking, dentistry, printing, etc.) and with different classes of materials and chemical products (glue, plastic, rubber...). These additional tests may also include personal items used by patients on a daily basis such as cosmetics, shoes, plants, textiles and so on.

  14. Chemical information science coverage in Chemical Abstracts.

    PubMed

    Wiggins, G

    1987-02-01

    For many years Chemical Abstracts has included in its coverage publications on chemical documentation or chemical information science. Although the bulk of those publications can be found in section 20 of Chemical Abstracts, many relevant articles were found scattered among 39 other sections of CA in 1984-1985. In addition to the scattering of references in CA, the comprehensiveness of Chemical Abstracts as a secondary source for chemical information science is called into question. Data are provided on the journals that contributed the most references on chemical information science and on the languages of publication of relevant articles.

  15. Delicious Chemicals.

    ERIC Educational Resources Information Center

    Barry, Dana M.

    This paper presents an approach to chemistry and nutrition that focuses on food items that people consider delicious. Information is organized according to three categories of food chemicals that provide energy to the human body: (1) fats and oils; (2) carbohydrates; and (3) proteins. Minerals, vitamins, and additives are also discussed along with…

  16. Decontamination formulation with sorbent additive

    DOEpatents

    Tucker; Mark D. , Comstock; Robert H.

    2007-10-16

    A decontamination formulation and method of making that neutralizes the adverse health effects of both chemical and biological compounds, especially chemical warfare (CW) and biological warfare (BW) agents, and toxic industrial chemicals. The formulation provides solubilizing compounds that serve to effectively render the chemical and biological compounds, particularly CW and BW compounds, susceptible to attack, and at least one reactive compound that serves to attack (and detoxify or kill) the compound. The formulation includes at least one solubilizing agent, a reactive compound, a bleaching activator, a sorbent additive, and water. The highly adsorbent, water-soluble sorbent additive (e.g., sorbitol or mannitol) is used to "dry out" one or more liquid ingredients, such as the liquid bleaching activator (e.g., propylene glycol diacetate or glycerol diacetate) and convert the activator into a dry, free-flowing powder that has an extended shelf life, and is more convenient to handle and mix in the field.

  17. Chemical sensors

    SciTech Connect

    Hubbard, C.W.; Gordon, R.L.

    1987-05-01

    The revolution in analytical chemistry promised by recent developments in the field of chemical sensors has potential for significant positive impact on both research and production activities conducted by and for the Department of Energy. Analyses which were, in the past, performed only with a roomful of expensive equipment can now be performed with miniature solid-state electronic devices or small optical probes. Progress in the development of chemical sensors has been rapid, and the field is currently growing at a great rate. In accordance, Pacific Northwest Laboratory initiated a survey of recent literature so that contributors to active programs in research on analytical methods could be made aware of principles and applications of this new technology. This report presents the results of that survey. The sensors discussed here are divided into three types: micro solid-state devices, optical sensors, and piezoelectric crystal devices. The report is divided into three corresponding sections. The first section, ''Micro Solid-State Devices,'' discusses the design, operation, and application of electronic sensors that are produced in much the same way as standard solid-state electronic devices. The second section, ''Optrodes,'' covers the design and operation of chemical sensors that use fiber optics to detect chemically induced changes in optical properties. The final section, ''Piezoelectric Crystal Detectors,'' discusses two types of chemical sensors that depend on the changes in the properties of an oscillating piezoelectric crystal to detect the presence of certain materials. Advantages and disadvantages of each type of sensor are summarized in each section.

  18. Processing of CuInSe{sub 2}-based solar cells: Characterization of deposition processes in terms of chemical reaction analyses. Phase 2 Annual Report, 6 May 1996--5 May 1997

    SciTech Connect

    Anderson, T.

    1999-10-20

    This report describes research performed by the University of Florida during Phase 2 of this subcontract. First, to study CIGS, researchers adapted a contactless, nondestructive technique previously developed for measuring photogenerated excess carrier lifetimes in SOI wafers. This dual-beam optical modulation (DBOM) technique was used to investigate the differences between three alternative methods of depositing CdS (conventional chemical-bath deposition [CBD], metal-organic chemical vapor deposition [MOCVD], and sputtering). Second, a critical assessment of the Cu-In-Se thermochemical and phase diagram data using standard CALPHAD procedures is being performed. The outcome of this research will produce useful information on equilibrium vapor compositions (required annealing ambients, Sex fluxes from effusion cells), phase diagrams (conditions for melt-assisted growth), chemical potentials (driving forces for diffusion and chemical reactions), and consistent solution models (extents of solid solutions and extending phase diagrams). Third, an integrated facility to fabricate CIS PV devices was established that includes migration-enhanced epitaxy (MEE) for deposition of CIS, a rapid thermal processing furnace for absorber film formation, sputtering of ZnO, CBD or MOCVD of CdS, metallization, and pattern definition.

  19. [Safety of food additives in Japan].

    PubMed

    Ito, Sumio

    2011-01-01

    Recently, many accidents relating to food happened in Japan. The consumer's distrust for food, food companies, and the administration is increasing. The consumer especially has an extreme refusal feeling for chemicals such as food additives and agricultural chemicals, and begins to request agricultural chemical-free vegetables and food additive-free food. Food companies also state no agricultural chemicals and no food additives to correspond with consumers' request and aim at differentiating. The food additive is that the Ministry of Health, Labour and Welfare specifies the one that person's health might not be ruined by providing for Food Sanitation Law Article 10 in our country. The standard for food additives and standard for use of food additives are provided according to regulations of Food Sanitation Law Article 11. Therefore, it is thought that the food additive used is safe now. Then, it reports on the procedure and the safety examination, etc. in our country for designation for food additive this time.

  20. Nanofibrillated cellulose as an additive in papermaking process: A review.

    PubMed

    Boufi, Sami; González, Israel; Delgado-Aguilar, Marc; Tarrès, Quim; Pèlach, M Àngels; Mutjé, Pere

    2016-12-10

    During the last two decades, cellulose nanofibres (CNF) have emerged as a promising, sustainable reinforcement with outstanding potential in material sciences. Though application of CNF in papermaking is recent, it is expected to find implementation in the near future to give a broader commercial market to this type of cellulose. The present review highlights recent progress in the field of the application of cellulose nanofibres as additives in papermaking. The effect of CNF addition on the wet end process is analysed according to the type of pulp used for papermaking. According to the literature consulted, improvement in paper's overall properties after CNF addition depended not only on the type and amount of CNF applied, but also in the pulp's origin and treatment. Bulk and surface application of CNF also presented significant differences regarding paper's final properties. This review also revises the mechanisms behind CNF reinforcing effect on paper and the effect of chemically modified CNF as additives. PMID:27577906

  1. Chemical and Thermal Analysis

    NASA Technical Reports Server (NTRS)

    Bulluck, J. W.; Rushing, R. A.

    1995-01-01

    During the past six months we have conducted significant research in several domains in order to clarify and understanding the aging and chemical failure mechanism of thermoplastics (PVDF or Tefzel) for pipes. We organized numerous analytical studies with methods including Fourier Transform Infrared Spectroscopy, Dynamic Mechanical Analysis, Differential Scanning Calorimetry, and Stress Relaxation experiments. In addition we have reanalyzed previous thermogravimetric data concerning the rate of deplasticization of Coflon pipe. We investigated a number of aged samples of both Tefzel and Coflon that were forwarded from MERL. We conducted stress relaxation experiments of Coflon pipe at several temperatures and determined an activation energy. We also examined the dynamic mechanical response PVDF during deplasticization and during methanol plasticization. We performed numerous DSC analyses to research the changing crystalline morphology. We have noted significant changes in crystallinity upon aging for both PVDF and Tefzel. Little variation in elemental composition was noted for many of the aged Coflon and Tefzel samples tested.

  2. Chemical generation and modification of peptides containing multiple dehydroalanines† †Electronic supplementary information (ESI) available. See DOI: 10.1039/c5cc05469a Click here for additional data file.

    PubMed Central

    Morrison, Philip M.; Foley, Patrick J.; Warriner, Stuart L.

    2015-01-01

    Chemical formation of dehydroalanine has been widely used for the post-translational modification of proteins and peptides, however methods to incorporate multiple dehydroalanine residues into a single peptide have not been defined. We report the use of methyl 2,5-dibromovalerate which can be used to cleanly carry out this transformation. PMID:26219458

  3. Correlated Raman micro-spectroscopy and scanning electron microscopy analyses of flame retardants in environmental samples: a micro-analytical tool for probing chemical composition, origin and spatial distribution.

    PubMed

    Ghosal, Sutapa; Wagner, Jeff

    2013-07-01

    We present correlated application of two micro-analytical techniques: scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS) and Raman micro-spectroscopy (RMS) for the non-invasive characterization and molecular identification of flame retardants (FRs) in environmental dusts and consumer products. The SEM/EDS-RMS technique offers correlated, morphological, molecular, spatial distribution and semi-quantitative elemental concentration information at the individual particle level with micrometer spatial resolution and minimal sample preparation. The presented methodology uses SEM/EDS analyses for rapid detection of particles containing FR specific elements as potential indicators of FR presence in a sample followed by correlated RMS analyses of the same particles for characterization of the FR sub-regions and surrounding matrices. The spatially resolved characterization enabled by this approach provides insights into the distributional heterogeneity as well as potential transfer and exposure mechanisms for FRs in the environment that is typically not available through traditional FR analysis. We have used this methodology to reveal a heterogeneous distribution of highly concentrated deca-BDE particles in environmental dust, sometimes in association with identifiable consumer materials. The observed coexistence of deca-BDE with consumer material in dust is strongly indicative of its release into the environment via weathering/abrasion of consumer products. Ingestion of such enriched FR particles in dust represents a potential for instantaneous exposure to high FR concentrations. Therefore, correlated SEM/RMS analysis offers a novel investigative tool for addressing an area of important environmental concern.

  4. {sup 13}C chemical shift anisotropies for carbonate ions in cement minerals and the use of {sup 13}C, {sup 27}Al and {sup 29}Si MAS NMR in studies of Portland cement including limestone additions

    SciTech Connect

    Sevelsted, Tine F.; Herfort, Duncan

    2013-10-15

    {sup 13}C isotropic chemical shifts and chemical shift anisotropy parameters have been determined for a number of inorganic carbonates relevant in cement chemistry from slow-speed {sup 13}C MAS or {sup 13}C({sup 1}H) CP/MAS NMR spectra (9.4 T or 14.1 T) for {sup 13}C in natural abundance. The variation in the {sup 13}C chemical shift parameters is relatively small, raising some doubts that different carbonate species in Portland cement-based materials may not be sufficiently resolved in {sup 13}C MAS NMR spectra. However, it is shown that by combining {sup 13}C MAS and {sup 13}C({sup 1}H) CP/MAS NMR carbonate anions in anhydrous and hydrated phases can be distinguished, thereby providing valuable information about the reactivity of limestone in cement blends. This is illustrated for three cement pastes prepared from an ordinary Portland cement, including 0, 16, and 25 wt.% limestone, and following the hydration for up to one year. For these blends {sup 29}Si MAS NMR reveals that the limestone filler accelerates the hydration for alite and also results in a smaller fraction of tetrahedrally coordinated Al incorporated in the C-S-H phase. The latter result is more clearly observed in {sup 27}Al MAS NMR spectra of the cement–limestone blends and suggests that dissolved aluminate species in the cement–limestone blends readily react with carbonate ions from the limestone filler, forming calcium monocarboaluminate hydrate. -- Highlights: •{sup 13}C chemical shift anisotropies for inorganic carbonates from {sup 13}C MAS NMR. •Narrow {sup 13}C NMR chemical shift range (163–171 ppm) for inorganic carbonates. •Anhydrous and hydrated carbonate species by {sup 13}C MAS and {sup 13}C({sup 1}H) CP/MAS NMR. •Limestone accelerates the hydration for alite in Portland – limestone cements. •Limestone reduces the amount of aluminium incorporated in the C-S-H phase.

  5. Lunar Science Conference, 4th, Houston, Tex., March 5-8, 1973, Proceedings. Volume 1 - Mineralogy and petrology. Volume 2 - Chemical and isotope analyses. Organic chemistry. Volume 3 - Physical properties

    NASA Technical Reports Server (NTRS)

    Gose, W. A.

    1973-01-01

    The mineralogy, petrology, chemistry, isotopic composition, and physical properties of lunar materials are described in papers detailing methods, results, and implications of research on samples returned from eight lunar landing sites: Apollo 11, 12, 14, 15, 16, 17, and Luna 16 and 20. The results of experiments conducted or set up on the lunar surface by the astronauts are also described along with observations taken from Command Modules and subsatellites. Major topics include general geology, soil and breccia studies, petrologic studies, mineralogic analyses, elemental compositions, radiometric age determinations, rare gas chemistry, radionuclides, organogenic compounds, particle track records, thermal properties, seismic studies, resonance studies, orbital mapping, lunar atmosphere, magnetic studies, electrical studies, optical properties, and microcratering. Individual items are announced in this issue.

  6. Nutrient addition to enhance biological treatment of greywater.

    PubMed

    Jefferson, B; Burgess, J E; Pichon, A; Harkness, J; Judd, S J

    2001-08-01

    This study compares the chemical oxygen demand (COD) removal and respiration rates of a microbial population treating real and synthetic greywaters dosed with nutrient supplements. The nutrient composition of the real and synthetic greywaters was analysed and the dosing regime for nitrogen, phosphorus and a range of trace metals planned accordingly. The doses consisted of eight single additives (macronutrients and trace metals) to the control greywater and six trace metal additions to C: N : P balanced greywater. The COD removal for the control real and synthetic greywater in lab-scale activated sludge systems (0.038 and 0.286 kg COD kg MLSS(-1) d(-1), respectively) confirmed nutrient limitation and the poor degree of greywater treatment. Nutrient dosing increased the COD removal rate and oxygen uptake rate in many cases. The greatest stimulation of microbial activity was observed with zinc additions to C: N: P balanced real greywater (1.291 kg COD kg MLSS(-1) d(-1) over 30 times the control). Inhibitory effects to various extents were rare and limited mainly to the additions of metals to synthetic greywater. The dominance of chemicals effects was observed on addition of some micronutrients; notably iron and aluminium, metals on which many coagulants for use in biotreatment of other wastewaters are based. The data indicate that the impact of understanding microbial processes and the nutrients required for wastewater treatment can only serve to optimise process efficiency for the proposed treatment of greywater.

  7. Biological aerosol warner and analyser

    NASA Astrophysics Data System (ADS)

    Schlemmer, Harry; Kürbitz, Gunther; Miethe, Peter; Spieweck, Michael

    2006-05-01

    The development of an integrated sensor device BiSAM (Biological Sampling and Analysing Module) is presented which is designed for rapid detection of aerosol or dust particles potentially loaded with biological warfare agents. All functional steps from aerosol collection via immuno analysis to display of results are fully automated. The core component of the sensor device is an ultra sensitive rapid analyser PBA (Portable Benchtop Analyser) based on a 3 dimensional immuno filtration column of large internal area, Poly HRP marker technology and kinetic optical detection. High sensitivity despite of the short measuring time, high chemical stability of the micro column and robustness against interferents make the PBA an ideal tool for fielded sensor devices. It is especially favourable to combine the PBA with a bio collector because virtually no sample preparation is necessary. Overall, the BiSAM device is capable to detect and identify living micro organisms (bacteria, spores, viruses) as well as toxins in a measuring cycle of typically half an hour duration. In each batch up to 12 different tests can be run in parallel together with positive and negative controls to keep the false alarm rate low.

  8. Comparison of gas chromatography-mass spectrometry and gas chromatography-tandem mass spectrometry with electron ionization and negative-ion chemical ionization for analyses of pesticides at trace levels in atmospheric samples.

    PubMed

    Raina, Renata; Hall, Patricia

    2008-09-09

    A comparison of detection limits of gas chromatography-mass spectrometry (GC-MS) in selected ion monitoring (SIM) with gas chromatography-tandem mass spectrometry (GC-MS/MS) in selected reaction monitoring (SRM) mode with both electron ionization (EI) and negative-ion chemical ionization (NCI) are presented for over 50 pesticides ranging from organochlorines (OCs), organophosphorus pesticides (OPs) and pre-emergent herbicides used in the Canadian prairies (triallate, trifluralin, ethalfluralin). The developed GC-EI/SIM, GC-NCI/SIM, and GC-NCI/SRM are suitable for the determination of pesticides in air sample extracts at concentrations <100 pg microL(-1) (<100 pg m(-3) in air). No one method could be used to analyze the range of pre-emergent herbicides, OPs, and OCs investigated. In general GC-NCI/SIM provided the lowest method detection limits (MDLs commonly 2.5-10 pg microL(-1)) along with best confirmation (<25% RSD of ion ratio), while GC-NCI/SRM is recommended for use where added selectivity or confirmation is required (such as parathion-ethyl, tokuthion, carbofenothion). GC-EI/SRM at concentration <100 pg microL(-1) was not suitable for most pesticides. GC-EI/SIM was more prone to interference issues than NCI methods, but gave good sensitivity (MDLs 1-10 pg microL(-1)) for pesticides with poor NCI response (OPs: sulfotep, phorate, aspon, ethion, and OCs: alachlor, aldrin, perthane, and DDE, DDD, DDT).

  9. Lunar Science Conference, 5th, Houston, Tex., March 18-22, 1974, Proceedings. Volume 1 - Mineralogy and petrology. Volume 2 Chemical and isotope analyses. Organic chemistry. Volume 3 - Physical properties

    NASA Technical Reports Server (NTRS)

    Gose, W. A.

    1974-01-01

    Numerous studies on the properties of the moon based on Apollo findings and samples are presented. Topics treated include ages of the lunar nearside light plains and maria, orange material in the Sulpicius Gallus formation at the southwestern edge of Mare Serenitatis, impact-induced fractionation in the lunar highlands, igneous rocks from Apollo 16 rake samples, experimental liquid line of descent and liquid immiscibility for basalt 70017, ion microprobe mass analysis of plagioclase from 'non-mare' lunar samples, grain size and the evolution of lunar soils, chemical composition of rocks and soils at Taurus-Littrow, the geochemical evolution of the moon, U-Th-Pb systematics of some Apollo 17 lunar samples and implications for a lunar basin excavation chronology, volatile-element systematics and green glass in Apollo 15 lunar soils, solar wind nitrogen and indigenous nitrogen in Apollo 17 lunar samples, lunar trapped xenon, solar flare and lunar surface process characterization at the Apollo 17 site, and the permanent and induced magnetic dipole moment of the moon. Individual items are announced in this issue.

  10. 10 CFR 436.24 - Uncertainty analyses.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... DEPARTMENT OF ENERGY ENERGY CONSERVATION FEDERAL ENERGY MANAGEMENT AND PLANNING PROGRAMS Methodology and... by conducting additional analyses using any standard engineering economics method such as sensitivity... energy or water system alternative....

  11. 10 CFR 436.24 - Uncertainty analyses.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... DEPARTMENT OF ENERGY ENERGY CONSERVATION FEDERAL ENERGY MANAGEMENT AND PLANNING PROGRAMS Methodology and... by conducting additional analyses using any standard engineering economics method such as sensitivity... energy or water system alternative....

  12. 10 CFR 436.24 - Uncertainty analyses.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Procedures for Life Cycle Cost Analyses § 436.24 Uncertainty analyses. If particular items of cost data or... impact of uncertainty on the calculation of life cycle cost effectiveness or the assignment of rank order... and probabilistic analysis. If additional analysis casts substantial doubt on the life cycle...

  13. 10 CFR 436.24 - Uncertainty analyses.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Procedures for Life Cycle Cost Analyses § 436.24 Uncertainty analyses. If particular items of cost data or... impact of uncertainty on the calculation of life cycle cost effectiveness or the assignment of rank order... and probabilistic analysis. If additional analysis casts substantial doubt on the life cycle...

  14. 10 CFR 436.24 - Uncertainty analyses.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Procedures for Life Cycle Cost Analyses § 436.24 Uncertainty analyses. If particular items of cost data or... impact of uncertainty on the calculation of life cycle cost effectiveness or the assignment of rank order... and probabilistic analysis. If additional analysis casts substantial doubt on the life cycle...

  15. Pressure Controlled Chemical Gardens.

    PubMed

    Bentley, Megan R; Batista, Bruno C; Steinbock, Oliver

    2016-06-30

    The dissolution of metal salts in silicate solution can result in the growth of hollow precipitate tubes. These "chemical gardens" are a model of self-organization far from the equilibrium and create permanent macroscopic structures. The reproducibility of the growth process is greatly improved if the solid salt seed is replaced by a salt solution that is steadily injected by a pump; however, this modification of the original experiment eliminates the membrane-based osmotic pump at the base of conventional chemical gardens and does not allow for analyses in terms of the involved pressure. Here we describe a new experimental method that delivers the salt solution according to a controlled hydrostatic pressure. In one form of the experiment, this pressure slowly decreases as zinc sulfate solution flows into the silicate-containing reaction vessel, whereas a second version holds the respective solution heights constant. In addition to three known growth regimes (jetting, popping, budding), we observe single tubes that fill the vessel in a horizontally undulating but vertically layered fashion (crowding). The resulting, dried product has a cylindrical shape, very low density, and one continuous connection from top to bottom. We also present phase diagrams of these growth modes and show that the flow characteristics of our experiments follow a reaction-independent Hagen-Poiseuille equation. PMID:27266993

  16. Evaluation of food additives as alternative or complementary chemicals to conventional fungicides for the control of major postharvest diseases of stone fruit for the control of major postharvest diseases of stone fruit

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Among more than twenty food additives and GRAS (generally regarded as safe) compounds that were tested at three concentrations in in vivo primary screenings with several cultivars of California peaches, nectarines, and plums that had been artificially inoculated with seven major postharvest pathogen...

  17. Evaluation of food-relevant chemicals in the ToxCast high-throughput screening program.

    PubMed

    Karmaus, Agnes L; Filer, Dayne L; Martin, Matthew T; Houck, Keith A

    2016-06-01

    Thousands of chemicals are directly added to or come in contact with food, many of which have undergone little to no toxicological evaluation. The landscape of the food-relevant chemical universe was evaluated using cheminformatics, and subsequently the bioactivity of food-relevant chemicals across the publicly available ToxCast highthroughput screening program was assessed. In total, 8659 food-relevant chemicals were compiled including direct food additives, food contact substances, and pesticides. Of these food-relevant chemicals, 4719 had curated structure definition files amenable to defining chemical fingerprints, which were used to cluster chemicals using a selforganizing map approach. Pesticides, and direct food additives clustered apart from one another with food contact substances generally in between, supporting that these categories not only reflect different uses but also distinct chemistries. Subsequently, 1530 food-relevant chemicals were identified in ToxCast comprising 616 direct food additives, 371 food contact substances, and 543 pesticides. Bioactivity across ToxCast was filtered for cytotoxicity to identify selective chemical effects. Initiating analyses from strictly chemical-based methodology or bioactivity/cytotoxicity-driven evaluation presents unbiased approaches for prioritizing chemicals. Although bioactivity in vitro is not necessarily predictive of adverse effects in vivo, these data provide insight into chemical properties and cellular targets through which foodrelevant chemicals elicit bioactivity.

  18. Evaluation of food-relevant chemicals in the ToxCast high-throughput screening program.

    PubMed

    Karmaus, Agnes L; Filer, Dayne L; Martin, Matthew T; Houck, Keith A

    2016-06-01

    Thousands of chemicals are directly added to or come in contact with food, many of which have undergone little to no toxicological evaluation. The landscape of the food-relevant chemical universe was evaluated using cheminformatics, and subsequently the bioactivity of food-relevant chemicals across the publicly available ToxCast highthroughput screening program was assessed. In total, 8659 food-relevant chemicals were compiled including direct food additives, food contact substances, and pesticides. Of these food-relevant chemicals, 4719 had curated structure definition files amenable to defining chemical fingerprints, which were used to cluster chemicals using a selforganizing map approach. Pesticides, and direct food additives clustered apart from one another with food contact substances generally in between, supporting that these categories not only reflect different uses but also distinct chemistries. Subsequently, 1530 food-relevant chemicals were identified in ToxCast comprising 616 direct food additives, 371 food contact substances, and 543 pesticides. Bioactivity across ToxCast was filtered for cytotoxicity to identify selective chemical effects. Initiating analyses from strictly chemical-based methodology or bioactivity/cytotoxicity-driven evaluation presents unbiased approaches for prioritizing chemicals. Although bioactivity in vitro is not necessarily predictive of adverse effects in vivo, these data provide insight into chemical properties and cellular targets through which foodrelevant chemicals elicit bioactivity. PMID:27103583

  19. Chemical changes in rubber allergens during vulcanization.

    PubMed

    Bergendorff, Ola; Persson, Christina; Lüdtke, Anna; Hansson, Christer

    2007-09-01

    Allergic contact dermatitis to rubber is caused by residues of chemicals used in manufacturing a rubber product. Several different additives are used to achieve a final product of the desired characteristics. Accelerators such as thiurams, dithiocarbamates, and mercaptobenzothiazoles are often among the additives responsible for allergic reactions recognized by dermatologists. The chemistry of the vulcanization process is complicated; as it occurs at an elevated temperature with a mixture of reactive chemicals, the compositions of the initial and final products differ. This paper investigates the changes in composition of common allergens during vulcanization, doing so by chemically analysing various rubber formulations at different stages of the process. Major changes were found in which added chemicals were consumed and new ones produced. An important observation is that thiuram disulfides rarely appear in the final rubber although they may have been used as additives. Instead, thiurams are often converted to dithiocarbamates or to products formed by addition to mercaptobenzothiazole structures, if these have been used together with thiurams as accelerators. PMID:17680862

  20. Chemical changes in rubber allergens during vulcanization.

    PubMed

    Bergendorff, Ola; Persson, Christina; Lüdtke, Anna; Hansson, Christer

    2007-09-01

    Allergic contact dermatitis to rubber is caused by residues of chemicals used in manufacturing a rubber product. Several different additives are used to achieve a final product of the desired characteristics. Accelerators such as thiurams, dithiocarbamates, and mercaptobenzothiazoles are often among the additives responsible for allergic reactions recognized by dermatologists. The chemistry of the vulcanization process is complicated; as it occurs at an elevated temperature with a mixture of reactive chemicals, the compositions of the initial and final products differ. This paper investigates the changes in composition of common allergens during vulcanization, doing so by chemically analysing various rubber formulations at different stages of the process. Major changes were found in which added chemicals were consumed and new ones produced. An important observation is that thiuram disulfides rarely appear in the final rubber although they may have been used as additives. Instead, thiurams are often converted to dithiocarbamates or to products formed by addition to mercaptobenzothiazole structures, if these have been used together with thiurams as accelerators.

  1. Ferreting Out the Identity of Gasoline Additives

    EPA Science Inventory

    Chemical dispersing agents for oil spills, hydraulic fracturing fluids for natural-gas production, and chemicals serving as gasoline additives share a common characteristic—for the most part, they are proprietary compounds. In the name of competitive advantage, companies carefull...

  2. NOAA's National Snow Analyses

    NASA Astrophysics Data System (ADS)

    Carroll, T. R.; Cline, D. W.; Olheiser, C. M.; Rost, A. A.; Nilsson, A. O.; Fall, G. M.; Li, L.; Bovitz, C. T.

    2005-12-01

    NOAA's National Operational Hydrologic Remote Sensing Center (NOHRSC) routinely ingests all of the electronically available, real-time, ground-based, snow data; airborne snow water equivalent data; satellite areal extent of snow cover information; and numerical weather prediction (NWP) model forcings for the coterminous U.S. The NWP model forcings are physically downscaled from their native 13 km2 spatial resolution to a 1 km2 resolution for the CONUS. The downscaled NWP forcings drive an energy-and-mass-balance snow accumulation and ablation model at a 1 km2 spatial resolution and at a 1 hour temporal resolution for the country. The ground-based, airborne, and satellite snow observations are assimilated into the snow model's simulated state variables using a Newtonian nudging technique. The principle advantages of the assimilation technique are: (1) approximate balance is maintained in the snow model, (2) physical processes are easily accommodated in the model, and (3) asynoptic data are incorporated at the appropriate times. The snow model is reinitialized with the assimilated snow observations to generate a variety of snow products that combine to form NOAA's NOHRSC National Snow Analyses (NSA). The NOHRSC NSA incorporate all of the available information necessary and available to produce a "best estimate" of real-time snow cover conditions at 1 km2 spatial resolution and 1 hour temporal resolution for the country. The NOHRSC NSA consist of a variety of daily, operational, products that characterize real-time snowpack conditions including: snow water equivalent, snow depth, surface and internal snowpack temperatures, surface and blowing snow sublimation, and snowmelt for the CONUS. The products are generated and distributed in a variety of formats including: interactive maps, time-series, alphanumeric products (e.g., mean areal snow water equivalent on a hydrologic basin-by-basin basis), text and map discussions, map animations, and quantitative gridded products

  3. Wavelet Analyses and Applications

    ERIC Educational Resources Information Center

    Bordeianu, Cristian C.; Landau, Rubin H.; Paez, Manuel J.

    2009-01-01

    It is shown how a modern extension of Fourier analysis known as wavelet analysis is applied to signals containing multiscale information. First, a continuous wavelet transform is used to analyse the spectrum of a nonstationary signal (one whose form changes in time). The spectral analysis of such a signal gives the strength of the signal in each…

  4. Apollo 14 microbial analyses

    NASA Technical Reports Server (NTRS)

    Taylor, G. R.

    1972-01-01

    Extensive microbiological analyses that were performed on the Apollo 14 prime and backup crewmembers and ancillary personnel are discussed. The crewmembers were subjected to four separate and quite different environments during the 137-day monitoring period. The relation between each of these environments and observed changes in the microflora of each astronaut are presented.

  5. Octacoordinated Dioxo-Molybdenum Complex via Formal Oxidative Addition of Molecular Oxygen. Studies of Chemical Reactions Between M(CO)6 (M = Cr, Mo) and 2,4-Di-tert-butyl-6-(pyridin-2-ylazo)-phenol.

    PubMed

    Chatterjee, Ipsita; Saha Chowdhury, Nabanita; Ghosh, Pradip; Goswami, Sreebrata

    2015-06-01

    Reactions of M(CO)6 (M = Mo, Cr) and 2 mol of 2,4-di-tert-butyl-6-(pyridin-2-ylazo)-phenol ligand (HL) in air yielded [Mo(VI)O2(L(1)¯)2], 1, and [Cr(III)(L(1)¯)(L(•2)¯)], 2, respectively, in high yields. Formation of the Cr-complex is a substitution reaction, which is associated with electron transfer, while that of Mo is an example of molecular oxygen activation. Isolated monoradical chromium complex 2 is susceptible to oxidation. Accordingly the reaction of 2 with the oxidant, I2 produces a cationic nonradical complex of chemical composition [Cr(III)(L(1)¯)2]I3, [2]I3 in almost quantitative yield. All the isolated complexes are primarily characterized by various spectroscopic techniques and magnetic measurements. While the molybdenum complex is diamagnetic, the two chromium complexes behave as simple paramagnets: μeff (295 K), 2.81 μB and 3.79 μB for 2 and [2]I3, respectively. Single-crystal three-dimensional X-ray structures of 1, 2, [2]I3 are reported. The geometry of the Mo-complex is square antiprism (octacoordination), and that of the Cr-complexes is distorted octahedral. Redox properties of the complexes are studied by cyclic voltammetry and constant potential coulometry. The data are analyzed based on density functional theoretical calculations of molecular orbitals of redox isomers of the Cr complexes. The results indicated that the redox events in the complexes occur at the ligand center. The oxidation state of Cr in 2 is further assessed by XPS measurements and compared with the reported systems.

  6. Droplet microfluidics in (bio)chemical analysis.

    PubMed

    Basova, Evgenia Yu; Foret, Frantisek

    2015-01-01

    Droplet microfluidics may soon change the paradigm of performing chemical analyses and related instrumentation. It can improve not only the analysis scale, possibility for sensitivity improvement, and reduced consumption of chemical and biological reagents, but also the speed of performing a variety of unit operations. At present, microfluidic platforms can reproducibly generate monodisperse droplet populations at kHz or higher rates with droplet sizes suitable for high-throughput experiments, single-cell detection or even single molecule analysis. In addition to being used as microreactors with volume in the micro- to femtoliter range, droplet based systems have also been used to directly synthesize particles and encapsulate biological entities for biomedicine and biotechnology applications. This minireview summarizes various droplet microfluidics operations and applications for (bio)chemical assays described in the literature during the past few years.

  7. Food additives and preschool children.

    PubMed

    Martyn, Danika M; McNulty, Breige A; Nugent, Anne P; Gibney, Michael J

    2013-02-01

    Food additives have been used throughout history to perform specific functions in foods. A comprehensive framework of legislation is in place within Europe to control the use of additives in the food supply and ensure they pose no risk to human health. Further to this, exposure assessments are regularly carried out to monitor population intakes and verify that intakes are not above acceptable levels (acceptable daily intakes). Young children may have a higher dietary exposure to chemicals than adults due to a combination of rapid growth rates and distinct food intake patterns. For this reason, exposure assessments are particularly important in this age group. The paper will review the use of additives and exposure assessment methods and examine factors that affect dietary exposure by young children. One of the most widely investigated unfavourable health effects associated with food additive intake in preschool-aged children are suggested adverse behavioural effects. Research that has examined this relationship has reported a variety of responses, with many noting an increase in hyperactivity as reported by parents but not when assessed using objective examiners. This review has examined the experimental approaches used in such studies and suggests that efforts are needed to standardise objective methods of measuring behaviour in preschool children. Further to this, a more holistic approach to examining food additive intakes by preschool children is advisable, where overall exposure is considered rather than focusing solely on behavioural effects and possibly examining intakes of food additives other than food colours.

  8. Laboratory calibration of the cassini cosmic dust analyser (CDA) using new, low density projectiles

    NASA Astrophysics Data System (ADS)

    Goldsworthy, B. J.; Burchell, M. J.; Cole, M. J.; Green, S. F.; Leese, M. R.; McBride, N.; McDonnell, J. A. M.; Müller, M.; Grün, E.; Srama, R.; Armes, S. P.; Khan, M. A.

    The Cassini Cosmic Dust Analyser (CDA), developed from the Galileo and Ulysses dust instruments with the addition of a Chemical Analyser, is currently travelling outward from the Earth (collecting data from March 1999 onward) to the Saturnian system (arrival 2004) via Jupiter. The Chemical Analyser will provide information on the elemental composition of impacting micrometeoroids through impact ionisation, time-of-flight mass spectrometry. A rigorous calibration programme primarily focussed upon the Chemical Analyser is in progress at the University of Kent at Canterbury. A 2-MV Van de Graaff electrostatic accelerator and CDA laboratory model are used to simulate impacts. Acceleration of revolutionary low density, polymer dust particles has enabled an insight into the response of CDA to molecularly bonded material with increasing event velocity. These conducting polymer coated polystyrene latex particles represent significantly better analogues for carbonaceous cosmic grains than more traditionally accelerated projectiles (e.g. iron) and have enabled complex organic spectra to be produced in the laboratory. The current status of an ongoing programme is reported. Three samples are presented, two polypyrrole coated latexes of differing size and one PEDOT-coated latex sample.

  9. Addition of nucleophiles on cyanoacetylene N≡CCH=CH-X (X = NH2, OH, SH, …). Synthesis and Physico-chemical Properties of Potential Prebiotic Compounds or Interstellar Molecules.

    NASA Astrophysics Data System (ADS)

    Guillemin, Jean-Claude

    Among the molecules detected to date in the interstellar medium (ISM), cyanopolyynes constitute a rich and important subset. These robust compounds exhibit special properties with respect to their reactivity and kinetic stability, and some have been found in other astrochemical environments, such as comets or in lab simulations of planetary atmospheres.[1] These systems are supposed to be good starting materials for the formation of new, more complex, astrochemical species, or amino acids on primitive Earth. The formal addition of water, hydrogen sulfur or ammonia on cyanoacetylene (H-C≡C-C≡N) gives the corresponding heterosubstitued acrylonitriles. We have extensively investigated the study of such adducts. With water, the formed cyanovinylalcohol (NC-CH=CH-OH) is in a tautomeric equilibrium with the kinetically more stable cyanoacetaldehyde (NC-CH2 CH(=O)). Isolation of these compounds in pure form is challenging but the gas phase infrared spectrum has been recorded. Reaction of ammonia with cyanoacetylene gives aminoacrylonitrile (H2 N-CH=CH-CN), a stable enamine; microwave and infrared spectra were obtained.[2] Similarly the MW spectrum of 3-mercapto-2-propenenitrile (HS-CH=CH-CN) has been recorded.[3] Attempts to detect both species in the ISM have been performed. A combined experimental and theoretical study on the gas-phase basicity and acidity of a series of cyanovinyl derivatives is also presented.[4] We will demonstrate that many particular physicochemical properties are associated to these simple adducts of cyanoacetylene, compounds often proposed as prebiotic molecules or components of the ISM. 1] S. W. Fow, K. Dose, Molecular Evolution and the Origin of Life, Marcel Dekker, Stateplace- New York, metricconverterProductID1977. A1977. A. Coustenis, T. Encrenaz, B. BJzard, B. Bjoraker, G. Graner, G. Dang-Nhu, E. AriJ, Icarus 1993, 102, 240 - 269. [2] Benidar, A. ; Guillemin, J.-C. ; M—, O. ; Y‡-ez, M. J. Phys. Chem. A. 2005, 109, 4705-4712. E

  10. The reaction of an iridium PNP complex with parahydrogen facilitates polarisation transfer without chemical change† †Electronic supplementary information (ESI) available: Sample preparation, signal enhancements and raw data. CCDC 1026865. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c4dt03088e Click here for additional data file. Click here for additional data file.

    PubMed Central

    Holmes, Arthur J.; Rayner, Peter J.; Cowley, Michael J.; Green, Gary G. R.; Whitwood, Adrian C.

    2015-01-01

    The short lived pincer complex [(C5H3N(CH2P(tBu)2)2)Ir(H)2(py)]BF4 is shown to be active for signal amplification by reversible exchange. This catalyst formulation enables the efficient transfer of polarization from parahydrogen to be placed into just a single molecule of the hyperpolarisation target, pyridine. When the catalysts 1H nuclei are replaced by 2H, increased levels of substrate hyperpolarization result and when the reverse situation is examined the catalyst itself is clearly visible through hyperpolarised signals. The ligand exchange pathways of [(C5H3N(CH2P(tBu)2)2)Ir(H)2(py)]BF4 that are associated with this process are shown to involve the formation of 16-electron [(C5H3N(CH2P(tBu)2)2)Ir(H)2]BF4 and the 18-electron H2 addition product [(C5H3N(CH2P(tBu)2)2)Ir(H)2(H2)]BF4. PMID:25410259

  11. 15 CFR 713.4 - Advance declaration requirements for additionally planned production, processing, or consumption...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING SCHEDULE 2 CHEMICALS § 713.4 Advance declaration requirements for additionally planned production... additionally planned production, processing, or consumption of Schedule 2 chemicals. 713.4 Section...

  12. 15 CFR 713.4 - Advance declaration requirements for additionally planned production, processing, or consumption...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING SCHEDULE 2 CHEMICALS § 713.4 Advance declaration requirements for additionally planned production... additionally planned production, processing, or consumption of Schedule 2 chemicals. 713.4 Section...

  13. 15 CFR 713.4 - Advance declaration requirements for additionally planned production, processing, or consumption...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... INDUSTRY AND SECURITY, DEPARTMENT OF COMMERCE CHEMICAL WEAPONS CONVENTION REGULATIONS ACTIVITIES INVOLVING SCHEDULE 2 CHEMICALS § 713.4 Advance declaration requirements for additionally planned production... additionally planned production, processing, or consumption of Schedule 2 chemicals. 713.4 Section...

  14. Hydrogen Safety Project: Chemical analysis support task. Window ``E`` analyses

    SciTech Connect

    Jones, T E; Campbell, J A; Hoppe, E W; Greenwood, L R; Gillespie, B M

    1992-09-01

    Core samples taken from tank 101-SY at Hanford during ``window E`` were analyzed for organic and radiochemical constituents by staff of the Analytical Chemistry Laboratory at Pacific Northwest Laboratory. Westinghouse Hanford company submitted these samples to the laboratory.

  15. Physical-chemical analyses of irradiated papayas ( Carica papaya L.)

    NASA Astrophysics Data System (ADS)

    Camargo, R. J.; Tadini, C. C.; Sabato, S. F.

    2007-11-01

    Papaya is cultivated in Espírito Santo State/Brazil and as it stands up to irradiation, it is important to validate this technology, since it is already being applied in some countries. Penetration energy, ratio (relation between soluble solids and titrable acidity) and skin color were evaluated to verify the influence of four different doses of irradiation (0.0, 0.5, 0.75 and 1.00 kGy) on papayas, during 21 days. As a result for the skin color and the penetration energy, it was found that in the first days after irradiation, these variables increased with increase in radiation dose; however, after a time lapse, the tendency inverted and the irradiated fruits had a slower ripening process. For the ratio, a very important variable that it is responsible for the fruit taste, no difference was found between irradiated and the control fruit. Color and texture measurements are dependent on the storage temperature.

  16. Organohelium compounds: structures, stabilities and chemical bonding analyses.

    PubMed

    Fourré, Isabelle; Alvarez, Elsa; Chaquin, Patrick

    2014-02-24

    This paper deals with the possibility of forming short and relatively strong carbon-helium bonds in small typical organic molecules through substitution of one or several H atoms by He(+). A structural and energetics study (based on high-level calculations) of this unusual bonding, as well as a topological characterization of the resulting cations, is undertaken. Stable species generally requires substitution of about half of the hydrogen atoms for formation. Under these conditions, the number of such species appears to be potentially unlimited. "True" C-He bonds exhibit equilibrium distances ranging from 1.327 (C2H2He2(2+)) to 1.129 Å (He2CO(2+)). The energies of neutral He releasing range from approximately 5 kcal mol(-1) [He2CO(2+), (Z)-C2H2He2(2+)] to 25 kcal mol(-1) (C2HHe3(3+)), but remain most frequently around 10 kcal mol(-1). However, most of He(+)-substituted hydrocarbons are metastable with respect to C-C cleavage, except derivatives of ethene. Atoms in molecules (AIM) and electron localization function (ELF) topological descriptors classify the C-He bond as a weak charge-shift interaction [S. Shaik, D. Danovich, B. Silvi, D. L. Lauvergnat, P. C. Hiberty, Chem. Eur. J. 2005, 11, 6358-6371] in agreement with a recent publication by Rzepa [S. H. Rzepa, Nat. Chem. 2010, 2, 390-393]. He2CO(2+) is the only investigated compound that presents a C-He bonding ELF basin, which indicates a non-negligible covalent contribution to the bond. Other modifications in the electronic structure, such as the breaking of the triple bond in ethyne derivatives or the loss of aromaticity in C6H3He3(3+), are also nicely revealed by the ELF topology. PMID:24488791

  17. Chemical analyses of soils and other surficial materials, Alaska

    USGS Publications Warehouse

    Gough, L.P.; Peard, J.L.; Severson, R.C.; Shacklette, H.T.; Thompkins, M.L.; Stewart, K.C.; Briggs, P.H.

    1984-01-01

    Introduction: The favorable response to the reports on the geochemistry of unconsolidated surficial materials of the conterminous United States (informally called the '50-mile geochemical survey,' Shacklette and others, 1971a, 1971b, 1973, and 1974) led us, in 1975, to initiate a somewhat similar survey of Alaska. The principal objective of studies of this type is to establish estimates of the abundance of elements in soils and other surficial materials. Such information is useful in the evaluation of geochemical data for (1) mineral resources, (2) environmental appraisals, and (3) the definition of broad-scale geochemical patterns. For about six years this effort progressed slowly on a non-funded, time-available basis. During fiscal years 1982 and 1983, however, some funds were made available through the USGS Energy Lands and Alaska Mineral Surveys programs which allowed for the completion of the field-work phase of the project. The sampling plan was kept simple because, as with the 50-mile study, the acquisition of samples depended on the voluntary cooperation of field personnel (only about 40 percent of the total number of samples was obtained by the authors).

  18. [Food additives and healthiness].

    PubMed

    Heinonen, Marina

    2014-01-01

    Additives are used for improving food structure or preventing its spoilage, for example. Many substances used as additives are also naturally present in food. The safety of additives is evaluated according to commonly agreed principles. If high concentrations of an additive cause adverse health effects for humans, a limit of acceptable daily intake (ADI) is set for it. An additive is a risk only when ADI is exceeded. The healthiness of food is measured on the basis of nutrient density and scientifically proven effects.

  19. LDEF Satellite Radiation Analyses

    NASA Technical Reports Server (NTRS)

    Armstrong, T. W.; Colborn, B. L.

    1996-01-01

    Model calculations and analyses have been carried out to compare with several sets of data (dose, induced radioactivity in various experiment samples and spacecraft components, fission foil measurements, and LET spectra) from passive radiation dosimetry on the Long Duration Exposure Facility (LDEF) satellite, which was recovered after almost six years in space. The calculations and data comparisons are used to estimate the accuracy of current models and methods for predicting the ionizing radiation environment in low earth orbit. The emphasis is on checking the accuracy of trapped proton flux and anisotropy models.

  20. Conversion of biomass to selected chemical products.

    PubMed

    Gallezot, Pierre

    2012-02-21

    This critical review provides a survey illustrated by recent references of different strategies to achieve a sustainable conversion of biomass to bioproducts. Because of the huge number of chemical products that can be potentially manufactured, a selection of starting materials and targeted chemicals has been done. Also, thermochemical conversion processes such as biomass pyrolysis or gasification as well as the synthesis of biofuels were not considered. The synthesis of chemicals by conversion of platform molecules obtained by depolymerisation and fermentation of biopolymers is presently the most widely envisioned approach. Successful catalytic conversion of these building blocks into intermediates, specialties and fine chemicals will be examined. However, the platform molecule value chain is in competition with well-optimised, cost-effective synthesis routes from fossil resources to produce chemicals that have already a market. The literature covering alternative value chains whereby biopolymers are converted in one or few steps to functional materials will be analysed. This approach which does not require the use of isolated, pure chemicals is well adapted to produce high tonnage products, such as paper additives, paints, resins, foams, surfactants, lubricants, and plasticisers. Another objective of the review was to examine critically the green character of conversion processes because using renewables as raw materials does not exempt from abiding by green chemistry principles (368 references). PMID:21909591

  1. Non-destructive infrared analyses: a method for provenance analyses of sandstones

    NASA Astrophysics Data System (ADS)

    Bowitz, Jörg; Ehling, Angela

    2008-12-01

    Infrared spectroscopy (IR spectroscopy) is commonly applied in the laboratory for mineral analyses in addition to XRD. Because such technical efforts are time and cost consuming, we present an infrared-based mobile method for non-destructive mineral and provenance analyses of sandstones. IR spectroscopy is based on activating chemical bonds. By irradiating a mineral mixture, special bonds are activated to vibrate depending on the bond energy (resonance vibration). Accordingly, the energy of the IR spectrum will be reduced thereby generating an absorption spectrum. The positions of the absorption maxima within the spectral region indicate the type of the bonds and in many cases identify minerals containing these bonds. The non-destructive reflection spectroscopy operates in the near infrared region (NIR) and can detect all common clay minerals as well as sulfates, hydroxides and carbonates. The spectra produced have been interpreted by computer using digital mineral libraries that have been especially collected for sandstones. The comparison of all results with XRD, RFA and interpretations of thin sections demonstrates impressively the accuracy and reliability of this method. Not only are different minerals detectable, but also differently ordered kaolinites and varieties of illites can be identified by the shape and size of the absorption bands. Especially clay minerals and their varieties in combination with their relative contents form the characteristic spectra of sandstones. Other components such as limonite, hematite and amorphous silica also influence the spectra. Sandstones, similar in colour and texture, often can be identified by their characteristic reflectance spectra. Reference libraries with more than 60 spectra of important German sandstones have been created to enable entirely computerized interpretations and identifications of these dimension stones. The analysis of infrared spectroscopy results is demonstrated with examples of different sandstones

  2. A computational method for the identification of new candidate carcinogenic and non-carcinogenic chemicals.

    PubMed

    Chen, Lei; Chu, Chen; Lu, Jing; Kong, Xiangyin; Huang, Tao; Cai, Yu-Dong

    2015-09-01

    Cancer is one of the leading causes of human death. Based on current knowledge, one of the causes of cancer is exposure to toxic chemical compounds, including radioactive compounds, dioxin, and arsenic. The identification of new carcinogenic chemicals may warn us of potential danger and help to identify new ways to prevent cancer. In this study, a computational method was proposed to identify potential carcinogenic chemicals, as well as non-carcinogenic chemicals. According to the current validated carcinogenic and non-carcinogenic chemicals from the CPDB (Carcinogenic Potency Database), the candidate chemicals were searched in a weighted chemical network constructed according to chemical-chemical interactions. Then, the obtained candidate chemicals were further selected by a randomization test and information on chemical interactions and structures. The analyses identified several candidate carcinogenic chemicals, while those candidates identified as non-carcinogenic were supported by a literature search. In addition, several candidate carcinogenic/non-carcinogenic chemicals exhibit structural dissimilarity with validated carcinogenic/non-carcinogenic chemicals.

  3. Fragrance chemicals in domestic and occupational products.

    PubMed

    Rastogi, S C; Heydorn, S; Johansen, J D; Basketter, D A

    2001-10-01

    Epidemiological studies have described an increasing prevalence of fragrance allergy and indicated an association with hand eczema. 59 domestic and occupational products intended for hand exposure were subjected to gas chromatography-mass spectrometric (GC-MS) analyses to test the hypothesis that fragrance chemicals known to have the potential to cause contact allergy but not included in fragrance mix (FM) may be common ingredients in these products. A quantitative analysis of 19 selected fragrances was performed by GC-MS. Further analysis of GC-MS data revealed the presence of 43 other fragrance chemicals/groups of fragrance chemicals in the products investigated. Among the 19 target substances the most commonly detected were limonene in 78%, linalool in 61% and citronellol in 47% of the products investigated. The FM ingredients were present in these products with the following frequencies: oak moss (evernic acid methylester) 2%, cinnamic alcohol 2%, cinnamic aldehyde (cinnamal) 3%, isoeugenol 5%, alpha-amylcinnamic aldehyde (amyl cinnamal) 8%, hydroxycitronellal 12%, eugenol 27%, and geraniol 41%. Thus, the chemical analyses of domestic and occupational products indicates that investigation of potential contact allergy related to these products types should consider fragrance allergens additional to those in the FM, since these may occur with high frequency.

  4. Automated nutrient analyses in seawater

    SciTech Connect

    Whitledge, T.E.; Malloy, S.C.; Patton, C.J.; Wirick, C.D.

    1981-02-01

    This manual was assembled for use as a guide for analyzing the nutrient content of seawater samples collected in the marine coastal zone of the Northeast United States and the Bering Sea. Some modifications (changes in dilution or sample pump tube sizes) may be necessary to achieve optimum measurements in very pronounced oligotrophic, eutrophic or brackish areas. Information is presented under the following section headings: theory and mechanics of automated analysis; continuous flow system description; operation of autoanalyzer system; cookbook of current nutrient methods; automated analyzer and data analysis software; computer interfacing and hardware modifications; and trouble shooting. The three appendixes are entitled: references and additional reading; manifold components and chemicals; and software listings. (JGB)

  5. Chemical recognition software

    SciTech Connect

    Wagner, J.S.; Trahan, M.W.; Nelson, W.E.; Hargis, P.H. Jr.; Tisone, G.C.

    1994-06-01

    We have developed a capability to make real time concentration measurements of individual chemicals in a complex mixture using a multispectral laser remote sensing system. Our chemical recognition and analysis software consists of three parts: (1) a rigorous multivariate analysis package for quantitative concentration and uncertainty estimates, (2) a genetic optimizer which customizes and tailors the multivariate algorithm for a particular application, and (3) an intelligent neural net chemical filter which pre-selects from the chemical database to find the appropriate candidate chemicals for quantitative analyses by the multivariate algorithms, as well as providing a quick-look concentration estimate and consistency check. Detailed simulations using both laboratory fluorescence data and computer synthesized spectra indicate that our software can make accurate concentration estimates from complex multicomponent mixtures, even when the mixture is noisy and contaminated with unknowns.

  6. Chemical recognition software

    SciTech Connect

    Wagner, J.S.; Trahan, M.W.; Nelson, W.E.; Hargis, P.J. Jr.; Tisone, G.C.

    1994-12-01

    We have developed a capability to make real time concentration measurements of individual chemicals in a complex mixture using a multispectral laser remote sensing system. Our chemical recognition and analysis software consists of three parts: (1) a rigorous multivariate analysis package for quantitative concentration and uncertainty estimates, (2) a genetic optimizer which customizes and tailors the multivariate algorithm for a particular application, and (3) an intelligent neural net chemical filter which pre-selects from the chemical database to find the appropriate candidate chemicals for quantitative analyses by the multivariate algorithms, as well as providing a quick-look concentration estimate and consistency check. Detailed simulations using both laboratory fluorescence data and computer synthesized spectra indicate that our software can make accurate concentration estimates from complex multicomponent mixtures. even when the mixture is noisy and contaminated with unknowns.

  7. Analyses/Testing

    NASA Astrophysics Data System (ADS)

    Valdez, David; Nagy, Ellen

    The characterization of phenolic resins by modern analytical techniques is detailed. Common wet chemical and ISO methods are referenced, yet the chapter's emphasis resides in the numerous advances in instrumental techniques. For instance, the authors make a special effort to illustrate the use of GC×GC, MALLS detector in GPC, and some LC-MS and TOF-MS applications. Larger sections on NMR and IR indicate the power of these tools for analysis and also contain peak position tables. Thermal analysis techniques, including rheometry, are discussed with experimental procedures and applications. Finally, microscopy, both optical, and SEM/X-ray, with sample preparation insights, are discussed. The chapter cites 115 papers using analytical chemistry techniques in the examination of phenolic polymers.

  8. LDEF Satellite Radiation Analyses

    NASA Technical Reports Server (NTRS)

    Armstrong, T. W.; Colborn, B. L.

    1996-01-01

    This report covers work performed by Science Applications International Corporation (SAIC) under contract NAS8-39386 from the NASA Marshall Space Flight Center entitled LDEF Satellite Radiation Analyses. The basic objective of the study was to evaluate the accuracy of present models and computational methods for defining the ionizing radiation environment for spacecraft in Low Earth Orbit (LEO) by making comparisons with radiation measurements made on the Long Duration Exposure Facility (LDEF) satellite, which was recovered after almost six years in space. The emphasis of the work here is on predictions and comparisons with LDEF measurements of induced radioactivity and Linear Energy Transfer (LET) measurements. These model/data comparisons have been used to evaluate the accuracy of current models for predicting the flux and directionality of trapped protons for LEO missions.

  9. EEG analyses with SOBI.

    SciTech Connect

    Glickman, Matthew R.; Tang, Akaysha

    2009-02-01

    The motivating vision behind Sandia's MENTOR/PAL LDRD project has been that of systems which use real-time psychophysiological data to support and enhance human performance, both individually and of groups. Relevant and significant psychophysiological data being a necessary prerequisite to such systems, this LDRD has focused on identifying and refining such signals. The project has focused in particular on EEG (electroencephalogram) data as a promising candidate signal because it (potentially) provides a broad window on brain activity with relatively low cost and logistical constraints. We report here on two analyses performed on EEG data collected in this project using the SOBI (Second Order Blind Identification) algorithm to identify two independent sources of brain activity: one in the frontal lobe and one in the occipital. The first study looks at directional influences between the two components, while the second study looks at inferring gender based upon the frontal component.

  10. Network Class Superposition Analyses

    PubMed Central

    Pearson, Carl A. B.; Zeng, Chen; Simha, Rahul

    2013-01-01

    Networks are often used to understand a whole system by modeling the interactions among its pieces. Examples include biomolecules in a cell interacting to provide some primary function, or species in an environment forming a stable community. However, these interactions are often unknown; instead, the pieces' dynamic states are known, and network structure must be inferred. Because observed function may be explained by many different networks (e.g., for the yeast cell cycle process [1]), considering dynamics beyond this primary function means picking a single network or suitable sample: measuring over all networks exhibiting the primary function is computationally infeasible. We circumvent that obstacle by calculating the network class ensemble. We represent the ensemble by a stochastic matrix , which is a transition-by-transition superposition of the system dynamics for each member of the class. We present concrete results for derived from Boolean time series dynamics on networks obeying the Strong Inhibition rule, by applying to several traditional questions about network dynamics. We show that the distribution of the number of point attractors can be accurately estimated with . We show how to generate Derrida plots based on . We show that -based Shannon entropy outperforms other methods at selecting experiments to further narrow the network structure. We also outline an experimental test of predictions based on . We motivate all of these results in terms of a popular molecular biology Boolean network model for the yeast cell cycle, but the methods and analyses we introduce are general. We conclude with open questions for , for example, application to other models, computational considerations when scaling up to larger systems, and other potential analyses. PMID:23565141

  11. Network class superposition analyses.

    PubMed

    Pearson, Carl A B; Zeng, Chen; Simha, Rahul

    2013-01-01

    Networks are often used to understand a whole system by modeling the interactions among its pieces. Examples include biomolecules in a cell interacting to provide some primary function, or species in an environment forming a stable community. However, these interactions are often unknown; instead, the pieces' dynamic states are known, and network structure must be inferred. Because observed function may be explained by many different networks (e.g., ≈ 10(30) for the yeast cell cycle process), considering dynamics beyond this primary function means picking a single network or suitable sample: measuring over all networks exhibiting the primary function is computationally infeasible. We circumvent that obstacle by calculating the network class ensemble. We represent the ensemble by a stochastic matrix T, which is a transition-by-transition superposition of the system dynamics for each member of the class. We present concrete results for T derived from boolean time series dynamics on networks obeying the Strong Inhibition rule, by applying T to several traditional questions about network dynamics. We show that the distribution of the number of point attractors can be accurately estimated with T. We show how to generate Derrida plots based on T. We show that T-based Shannon entropy outperforms other methods at selecting experiments to further narrow the network structure. We also outline an experimental test of predictions based on T. We motivate all of these results in terms of a popular molecular biology boolean network model for the yeast cell cycle, but the methods and analyses we introduce are general. We conclude with open questions for T, for example, application to other models, computational considerations when scaling up to larger systems, and other potential analyses. PMID:23565141

  12. Uncertainty and Sensitivity Analyses Plan

    SciTech Connect

    Simpson, J.C.; Ramsdell, J.V. Jr.

    1993-04-01

    Hanford Environmental Dose Reconstruction (HEDR) Project staff are developing mathematical models to be used to estimate the radiation dose that individuals may have received as a result of emissions since 1944 from the US Department of Energy's (DOE) Hanford Site near Richland, Washington. An uncertainty and sensitivity analyses plan is essential to understand and interpret the predictions from these mathematical models. This is especially true in the case of the HEDR models where the values of many parameters are unknown. This plan gives a thorough documentation of the uncertainty and hierarchical sensitivity analysis methods recommended for use on all HEDR mathematical models. The documentation includes both technical definitions and examples. In addition, an extensive demonstration of the uncertainty and sensitivity analysis process is provided using actual results from the Hanford Environmental Dose Reconstruction Integrated Codes (HEDRIC). This demonstration shows how the approaches used in the recommended plan can be adapted for all dose predictions in the HEDR Project.

  13. Database-Driven Analyses of Astronomical Spectra

    NASA Astrophysics Data System (ADS)

    Cami, Jan

    2012-03-01

    species to the fullerene species C60 and C70 [4]. Given the large number and variety of molecules detected in space, molecular infrared spectroscopy can be used to study pretty much any astrophysical environment that is not too energetic to dissociate the molecules. At the lowest energies, it is interesting to note that molecules such as CN have been used to measure the temperature of the Cosmic Microwave Background (see e.g., Ref. 15). The great diagnostic potential of infrared molecular spectroscopy comes at a price though. Extracting the physical parameters from the observations requires expertise in knowing how various physical processes and instrumental characteristics play together in producing the observed spectra. In addition to the astronomical aspects, this often includes interpreting and understanding the limitations of laboratory data and quantum-chemical calculations; the study of the interaction of matter with radiation at microscopic scales (called radiative transfer, akin to ray tracing) and the effects of observing (e.g., smoothing and resampling) on the resulting spectra and possible instrumental effects (e.g., fringes). All this is not trivial. To make matters worse, observational spectra often contain many components, and might include spectral contributions stemming from very different physical conditions. Fully analyzing such observations is thus a time-consuming task that requires mastery of several techniques. And with ever-increasing rates of observational data acquisition, it seems clear that in the near future, some form of automation is required to handle the data stream. It is thus appealing to consider what part of such analyses could be done without too much human intervention. Two different aspects can be separated: the first step involves simply identifying the molecular species present in the observations. Once the molecular inventory is known, we can try to extract the physical parameters from the observed spectral properties. For both

  14. Towards interoperable and reproducible QSAR analyses: Exchange of datasets

    PubMed Central

    2010-01-01

    Background QSAR is a widely used method to relate chemical structures to responses or properties based on experimental observations. Much effort has been made to evaluate and validate the statistical modeling in QSAR, but these analyses treat the dataset as fixed. An overlooked but highly important issue is the validation of the setup of the dataset, which comprises addition of chemical structures as well as selection of descriptors and software implementations prior to calculations. This process is hampered by the lack of standards and exchange formats in the field, making it virtually impossible to reproduce and validate analyses and drastically constrain collaborations and re-use of data. Results We present a step towards standardizing QSAR analyses by defining interoperable and reproducible QSAR datasets, consisting of an open XML format (QSAR-ML) which builds on an open and extensible descriptor ontology. The ontology provides an extensible way of uniquely defining descriptors for use in QSAR experiments, and the exchange format supports multiple versioned implementations of these descriptors. Hence, a dataset described by QSAR-ML makes its setup completely reproducible. We also provide a reference implementation as a set of plugins for Bioclipse which simplifies setup of QSAR datasets, and allows for exporting in QSAR-ML as well as old-fashioned CSV formats. The implementation facilitates addition of new descriptor implementations from locally installed software and remote Web services; the latter is demonstrated with REST and XMPP Web services. Conclusions Standardized QSAR datasets open up new ways to store, query, and exchange data for subsequent analyses. QSAR-ML supports completely reproducible creation of datasets, solving the problems of defining which software components were used and their versions, and the descriptor ontology eliminates confusions regarding descriptors by defining them crisply. This makes is easy to join, extend, combine datasets

  15. 75 FR 53867 - Additions to Listing of Exempt Chemical Mixtures

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-09-02

    ... Product name \\1\\ Form Date Cerilliant Corporation 1R,2S(-)-Ephedrine hydrochloride 1.0 Liquid 8/2/2007 mg...(+)-Ephedrine-D3 hydrochloride Liquid 8/2/2007 0.1 mg/ml as free base in one of: 1,2- dimethoxyethane... tetrahydrofuran. ] Cerilliant Corporation 1S,2R(+)-Ephedrine-D3 hydrochloride Liquid 8/2/2007 1.0 mg/ml as...

  16. Buckyball additives improve lubrication

    SciTech Connect

    1996-08-31

    When researchers discovered the buckminsterfullerene molecule in 1985, it was considered the ideal candidate for reducing friction between tiny moving components. However, subsequently buckyballs were discovered not to be particularly good lubricators. Now, a team of chemical engineers and chemists has discovered that C60 molecules dissolved in the organic solvent toluene greatly reduce the friction between the liquid and the surface across which it flows.

  17. Hand chemical burns.

    PubMed

    Robinson, Elliot P; Chhabra, A Bobby

    2015-03-01

    There is a vast and ever-expanding variety of potentially harmful chemicals in the military, industrial, and domestic landscape. Chemical burns make up a small proportion of all skin burns, yet they can cause substantial morbidity and mortality. Additionally, the hand and upper extremity are the most frequently involved parts of the body in chemical burns, and therefore these injuries may lead to severe temporary or permanent loss of function. Despite this fact, discussion of the care of these injuries is sparse in the hand surgery literature. Although most chemical burns require only first response and wound care, some require the attention of a specialist for surgical debridement and, occasionally, skin coverage and reconstruction. Exposure to certain chemicals carries the risk of substantial systemic toxicity and even mortality. Understanding the difference between thermal and chemical burns, as well as special considerations for specific compounds, will improve patient treatment outcomes.

  18. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Fletcher, James C. (Inventor); Pratt, J. Richard (Inventor); St.clair, Terry L. (Inventor); Stoakley, Diane M. (Inventor); Burks, Harold D. (Inventor)

    1992-01-01

    A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly-(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15 percent by weight of additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA.

  19. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Pratt, J. Richard (Inventor); St.clair, Terry L. (Inventor); Stoakley, Diane M. (Inventor); Burks, Harold D. (Inventor)

    1993-01-01

    A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly-(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15 percent by weight of the additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA.

  20. Additional Types of Neuropathy

    MedlinePlus

    ... A A Listen En Español Additional Types of Neuropathy Charcot's Joint Charcot's Joint, also called neuropathic arthropathy, ... can stop bone destruction and aid healing. Cranial Neuropathy Cranial neuropathy affects the 12 pairs of nerves ...

  1. Food Additives and Hyperkinesis

    ERIC Educational Resources Information Center

    Wender, Ester H.

    1977-01-01

    The hypothesis that food additives are causally associated with hyperkinesis and learning disabilities in children is reviewed, and available data are summarized. Available from: American Medical Association 535 North Dearborn Street Chicago, Illinois 60610. (JG)

  2. Smog control fuel additives

    SciTech Connect

    Lundby, W.

    1993-06-29

    A method is described of controlling, reducing or eliminating, ozone and related smog resulting from photochemical reactions between ozone and automotive or industrial gases comprising the addition of iodine or compounds of iodine to hydrocarbon-base fuels prior to or during combustion in an amount of about 1 part iodine per 240 to 10,000,000 parts fuel, by weight, to be accomplished by: (a) the addition of these inhibitors during or after the refining or manufacturing process of liquid fuels; (b) the production of these inhibitors for addition into fuel tanks, such as automotive or industrial tanks; or (c) the addition of these inhibitors into combustion chambers of equipment utilizing solid fuels for the purpose of reducing ozone.

  3. Chemical process hazards analysis

    SciTech Connect

    1996-02-01

    The Office of Worker Health and Safety (EH-5) under the Assistant Secretary for the Environment, Safety and Health of the US Department (DOE) has published two handbooks for use by DOE contractors managing facilities and processes covered by the Occupational Safety and Health Administration (OSHA) Rule for Process Safety Management of Highly Hazardous Chemicals (29 CFR 1910.119), herein referred to as the PSM Rule. The PSM Rule contains an integrated set of chemical process safety management elements designed to prevent chemical releases that can lead to catastrophic fires, explosions, or toxic exposures. The purpose of the two handbooks, ``Process Safety Management for Highly Hazardous Chemicals`` and ``Chemical Process Hazards Analysis,`` is to facilitate implementation of the provisions of the PSM Rule within the DOE. The purpose of this handbook ``Chemical Process Hazards Analysis,`` is to facilitate, within the DOE, the performance of chemical process hazards analyses (PrHAs) as required under the PSM Rule. It provides basic information for the performance of PrHAs, and should not be considered a complete resource on PrHA methods. Likewise, to determine if a facility is covered by the PSM rule, the reader should refer to the handbook, ``Process Safety Management for Highly Hazardous Chemicals`` (DOE- HDBK-1101-96). Promulgation of the PSM Rule has heightened the awareness of chemical safety management issues within the DOE. This handbook is intended for use by DOE facilities and processes covered by the PSM rule to facilitate contractor implementation of the PrHA element of the PSM Rule. However, contractors whose facilities and processes not covered by the PSM Rule may also use this handbook as a basis for conducting process hazards analyses as part of their good management practices. This handbook explains the minimum requirements for PrHAs outlined in the PSM Rule. Nowhere have requirements been added beyond what is specifically required by the rule.

  4. Fire-Retardant Polymeric Additives

    NASA Technical Reports Server (NTRS)

    Williams, Martha K.; Smith, Trent M.

    2011-01-01

    Polyhydroxyamide (PHA) and polymethoxyamide (PMeOA) are fire-retardant (FR) thermoplastic polymers and have been found to be useful as an additive for imparting fire retardant properties to other compatible, thermoplastic polymers (including some elastomers). Examples of compatible flammable polymers include nylons, polyesters, and acrylics. Unlike most prior additives, PHA and PMeOA do not appreciably degrade the mechanical properties of the matrix polymer; indeed, in some cases, mechanical properties are enhanced. Also, unlike some prior additives, PHA and PMeOA do not decompose into large amounts of corrosive or toxic compounds during combustion and can be processed at elevated temperatures. PMeOA derivative formulations were synthesized and used as an FR additive in the fabrication of polyamide (PA) and polystyrene (PS) composites with notable reduction (>30 percent for PS) in peak heat release rates compared to the neat polymer as measured by a Cone Calorimeter (ASTM E1354). Synergistic effects were noted with nanosilica composites. These nanosilica composites had more than 50-percent reduction in peak heat release rates. In a typical application, a flammable thermoplastic, thermoplastic blend, or elastomer that one seeks to render flame-retardant is first dry-mixed with PHA or PMeOA or derivative thereof. The proportion of PHA or PMeOA or derivative in the mixture is typically chosen to lie between 1 and 20 weight percent. The dry blend can then be melt-extruded. The extruded polymer blend can further be extruded and/or molded into fibers, pipes, or any other of a variety of objects that may be required to be fire-retardant. The physical and chemical mechanisms which impart flame retardancy of the additive include inhibiting free-radical oxidation in the vapor phase, preventing vaporization of fuel (the polymer), and cooling through the formation of chemical bonds in either the vapor or the condensed phase. Under thermal stress, the cyclic hydroxyl/ methoxy

  5. Quantification of chemical contaminants in the paper and board fractions of municipal solid waste.

    PubMed

    Pivnenko, K; Olsson, M E; Götze, R; Eriksson, E; Astrup, T F

    2016-05-01

    Chemicals are used in materials as additives in order to improve the performance of the material or the production process itself. The presence of these chemicals in recyclable waste materials may potentially affect the recyclability of the materials. The addition of chemicals may vary depending on the production technology or the potential end-use of the material. Paper has been previously shown to potentially contain a large variety of chemicals. Quantitative data on the presence of chemicals in paper are necessary for appropriate waste paper management, including the recycling and re-processing of paper. However, a lack of quantitative data on the presence of chemicals in paper is evident in the literature. The aim of the present work is to quantify the presence of selected chemicals in waste paper derived from households. Samples of paper and board were collected from Danish households, including both residual and source-segregated materials, which were disposed of (e.g., through incineration) and recycled, respectively. The concentration of selected chemicals was quantified for all of the samples. The quantified chemicals included mineral oil hydrocarbons, phthalates, phenols, polychlorinated biphenyls, and selected toxic metals (Cd, Co, Cr, Cu, Ni, and Pb). The results suggest large variations in the concentration of chemicals depending on the waste paper fraction analysed. Research on the fate of chemicals in waste recycling and potential problem mitigation measures should be focused on in further studies.

  6. Chemical Reactors.

    ERIC Educational Resources Information Center

    Kenney, C. N.

    1980-01-01

    Describes a course, including content, reading list, and presentation on chemical reactors at Cambridge University, England. A brief comparison of chemical engineering education between the United States and England is also given. (JN)

  7. 49 CFR 1180.7 - Market analyses.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... identify and address relevant markets and issues, and provide additional information as requested by the...). (b) For major transactions, applicants shall submit “full system” impact analyses (incorporating any... (including inter- and intramodal competition, product competition, and geographic competition) and...

  8. Additive Manufacturing Infrared Inspection

    NASA Technical Reports Server (NTRS)

    Gaddy, Darrell

    2014-01-01

    Additive manufacturing is a rapid prototyping technology that allows parts to be built in a series of thin layers from plastic, ceramics, and metallics. Metallic additive manufacturing is an emerging form of rapid prototyping that allows complex structures to be built using various metallic powders. Significant time and cost savings have also been observed using the metallic additive manufacturing compared with traditional techniques. Development of the metallic additive manufacturing technology has advanced significantly over the last decade, although many of the techniques to inspect parts made from these processes have not advanced significantly or have limitations. Several external geometry inspection techniques exist such as Coordinate Measurement Machines (CMM), Laser Scanners, Structured Light Scanning Systems, or even traditional calipers and gages. All of the aforementioned techniques are limited to external geometry and contours or must use a contact probe to inspect limited internal dimensions. This presentation will document the development of a process for real-time dimensional inspection technique and digital quality record of the additive manufacturing process using Infrared camera imaging and processing techniques.

  9. Descriptive and Experimental Analyses of Potential Precursors to Problem Behavior

    ERIC Educational Resources Information Center

    Borrero, Carrie S. W.; Borrero, John C.

    2008-01-01

    We conducted descriptive observations of severe problem behavior for 2 individuals with autism to identify precursors to problem behavior. Several comparative probability analyses were conducted in addition to lag-sequential analyses using the descriptive data. Results of the descriptive analyses showed that the probability of the potential…

  10. Chemical sensor

    NASA Technical Reports Server (NTRS)

    Rauh, R. David (Inventor)

    1990-01-01

    A sensor for detecting a chemical substance includes an insertion element having a structure which enables insertion of the chemical substance with a resulting change in the bulk electrical characteristics of the insertion element under conditions sufficient to permit effective insertion; the change in the bulk electrical characteristics of the insertion element is detected as an indication of the presence of the chemical substance.

  11. Multifunctional fuel additives

    SciTech Connect

    Baillargeon, D.J.; Cardis, A.B.; Heck, D.B.

    1991-03-26

    This paper discusses a composition comprising a major amount of a liquid hydrocarbyl fuel and a minor low-temperature flow properties improving amount of an additive product of the reaction of a suitable diol and product of a benzophenone tetracarboxylic dianhydride and a long-chain hydrocarbyl aminoalcohol.

  12. Biobased lubricant additives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fully biobased lubricants are those formulated using all biobased ingredients, i.e. biobased base oils and biobased additives. Such formulations provide the maximum environmental, safety, and economic benefits expected from a biobased product. Currently, there are a number of biobased base oils that...

  13. ITER Safety Analyses with ISAS

    NASA Astrophysics Data System (ADS)

    Gulden, W.; Nisan, S.; Porfiri, M.-T.; Toumi, I.; de Gramont, T. Boubée

    1997-06-01

    Detailed analyses of accident sequences for the International Thermonuclear Experimental Reactor (ITER), from an initiating event to the environmental release of activity, have involved in the past the use of different types of computer codes in a sequential manner. Since these codes were developed at different time scales in different countries, there is no common computing structure to enable automatic data transfer from one code to the other, and no possibility exists to model or to quantify the effect of coupled physical phenomena. To solve this problem, the Integrated Safety Analysis System of codes (ISAS) is being developed, which allows users to integrate existing computer codes in a coherent manner. This approach is based on the utilization of a command language (GIBIANE) acting as a “glue” to integrate the various codes as modules of a common environment. The present version of ISAS allows comprehensive (coupled) calculations of a chain of codes such as ATHENA (thermal-hydraulic analysis of transients and accidents), INTRA (analysis of in-vessel chemical reactions, pressure built-up, and distribution of reaction products inside the vacuum vessel and adjacent rooms), and NAUA (transport of radiological species within buildings and to the environment). In the near future, the integration of S AFALY (simultaneous analysis of plasma dynamics and thermal behavior of in-vessel components) is also foreseen. The paper briefly describes the essential features of ISAS development and the associated software architecture. It gives first results of a typical ITER accident sequence, a loss of coolant accident (LOCA) in the divertor cooling loop inside the vacuum vessel, amply demonstrating ISAS capabilities.

  14. Solar Electric and Chemical Propulsion for a Titan Mission

    NASA Technical Reports Server (NTRS)

    Cupples, Michael; Green, Shaun E.; Donahue, Benjamin B.; Coverstone, Victoria L.

    2005-01-01

    Systems analyses were performed for a Titan Explorer Mission characterized by Earth-Saturn transfer stages using solar electric power generation and propulsion systems for primary interplanetary propulsion, and chemical propulsion for capture at Titan. An examination of a range of system factors was performed to determine their effect on the payload delivery capability to Titan. The effect of varying launch vehicle type, solar array power level, ion thruster number, specific impulse, trip time, and Titan capture stage chemical propellant choice was investigated. The major purpose of the study was to demonstrate the efficacy of applying advanced ion propulsion system technologies like NASA's Evolutionary Xenon Thruster (NEXT), coupled with state-of-the-art (SOA) and advanced chemical technologies to a Flagship class mission. This study demonstrated that a NASA Design Reference Mission (DRM) payload of 406 kg could be successfully delivered to Titan using the baseline advanced ion propulsion system in conjunction with SOA chemical propulsion for Titan capture. In addition, the SEPS/Chemical system of this study is compared to an all- chemical NASA DRM mission. Results showed that the NEXT- based SEPS/Chemical system was able to deliver the required payload to Titan in 5 years less transfer time and on a smaller launch vehicle than the SOA chemical option.

  15. Tough, High-Performance, Thermoplastic Addition Polymers

    NASA Technical Reports Server (NTRS)

    Pater, Ruth H.; Proctor, K. Mason; Gleason, John; Morgan, Cassandra; Partos, Richard

    1991-01-01

    Series of addition-type thermoplastics (ATT's) exhibit useful properties. Because of their addition curing and linear structure, ATT polymers have toughness, like thermoplastics, and easily processed, like thermosets. Work undertaken to develop chemical reaction forming stable aromatic rings in backbone of ATT polymer, combining high-temperature performance and thermo-oxidative stability with toughness and easy processibility, and minimizing or eliminating necessity for tradeoffs among properties often observed in conventional polymer syntheses.

  16. 14 CFR 437.77 - Additional safety requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., DEPARTMENT OF TRANSPORTATION LICENSING EXPERIMENTAL PERMITS Safety Requirements § 437.77 Additional safety... solid propellants. The FAA may also require the permittee to conduct additional analyses of the cause...

  17. Vinyl capped addition polyimides

    NASA Technical Reports Server (NTRS)

    Vannucci, Raymond D. (Inventor); Malarik, Diane C. (Inventor); Delvigs, Peter (Inventor)

    1991-01-01

    Polyimide resins (PMR) are generally useful where high strength and temperature capabilities are required (at temperatures up to about 700 F). Polyimide resins are particularly useful in applications such as jet engine compressor components, for example, blades, vanes, air seals, air splitters, and engine casing parts. Aromatic vinyl capped addition polyimides are obtained by reacting a diamine, an ester of tetracarboxylic acid, and an aromatic vinyl compound. Low void materials with improved oxidative stability when exposed to 700 F air may be fabricated as fiber reinforced high molecular weight capped polyimide composites. The aromatic vinyl capped polyimides are provided with a more aromatic nature and are more thermally stable than highly aliphatic, norbornenyl-type end-capped polyimides employed in PMR resins. The substitution of aromatic vinyl end-caps for norbornenyl end-caps in addition polyimides results in polymers with improved oxidative stability.

  18. Tackifier for addition polyimides

    NASA Technical Reports Server (NTRS)

    Butler, J. M.; St.clair, T. L.

    1980-01-01

    A modification to the addition polyimide, LaRC-160, was prepared to improve tack and drape and increase prepeg out-time. The essentially solventless, high viscosity laminating resin is synthesized from low cost liquid monomers. The modified version takes advantage of a reactive, liquid plasticizer which is used in place of solvent and helps solve a major problem of maintaining good prepeg tack and drape, or the ability of the prepeg to adhere to adjacent plies and conform to a desired shape during the lay up process. This alternate solventless approach allows both longer life of the polymer prepeg and the processing of low void laminates. This approach appears to be applicable to all addition polyimide systems.

  19. Electrophilic addition of astatine

    SciTech Connect

    Norseev, Yu.V.; Vasaros, L.; Nhan, D.D.; Huan, N.K.

    1988-03-01

    It has been shown for the first time that astatine is capable of undergoing addition reactions to unsaturated hydrocarbons. A new compound of astatine, viz., ethylene astatohydrin, has been obtained, and its retention numbers of squalane, Apiezon, and tricresyl phosphate have been found. The influence of various factors on the formation of ethylene astatohydrin has been studied. It has been concluded on the basis of the results obtained that the univalent cations of astatine in an acidic medium is protonated hypoastatous acid.

  20. Functional Generalized Additive Models.

    PubMed

    McLean, Mathew W; Hooker, Giles; Staicu, Ana-Maria; Scheipl, Fabian; Ruppert, David

    2014-01-01

    We introduce the functional generalized additive model (FGAM), a novel regression model for association studies between a scalar response and a functional predictor. We model the link-transformed mean response as the integral with respect to t of F{X(t), t} where F(·,·) is an unknown regression function and X(t) is a functional covariate. Rather than having an additive model in a finite number of principal components as in Müller and Yao (2008), our model incorporates the functional predictor directly and thus our model can be viewed as the natural functional extension of generalized additive models. We estimate F(·,·) using tensor-product B-splines with roughness penalties. A pointwise quantile transformation of the functional predictor is also considered to ensure each tensor-product B-spline has observed data on its support. The methods are evaluated using simulated data and their predictive performance is compared with other competing scalar-on-function regression alternatives. We illustrate the usefulness of our approach through an application to brain tractography, where X(t) is a signal from diffusion tensor imaging at position, t, along a tract in the brain. In one example, the response is disease-status (case or control) and in a second example, it is the score on a cognitive test. R code for performing the simulations and fitting the FGAM can be found in supplemental materials available online.

  1. Criteria for deviation from predictions by the concentration addition model.

    PubMed

    Takeshita, Jun-Ichi; Seki, Masanori; Kamo, Masashi

    2016-07-01

    Loewe's additivity (concentration addition) is a well-known model for predicting the toxic effects of chemical mixtures under the additivity assumption of toxicity. However, from the perspective of chemical risk assessment and/or management, it is important to identify chemicals whose toxicities are additive when present concurrently, that is, it should be established whether there are chemical mixtures to which the concentration addition predictive model can be applied. The objective of the present study was to develop criteria for judging test results that deviated from the predictions by the concentration addition chemical mixture model. These criteria were based on the confidence interval of the concentration addition model's prediction and on estimation of errors of the predicted concentration-effect curves by toxicity tests after exposure to single chemicals. A log-logit model with 2 parameters was assumed for the concentration-effect curve of each individual chemical. These parameters were determined by the maximum-likelihood method, and the criteria were defined using the variances and the covariance of the parameters. In addition, the criteria were applied to a toxicity test of a binary mixture of p-n-nonylphenol and p-n-octylphenol using the Japanese killifish, medaka (Oryzias latipes). Consequently, the concentration addition model using confidence interval was capable of predicting the test results at any level, and no reason for rejecting the concentration addition was found. Environ Toxicol Chem 2016;35:1806-1814. © 2015 SETAC. PMID:26660330

  2. [Chemical weapons and chemical terrorism].

    PubMed

    Nakamura, Katsumi

    2005-10-01

    Chemical Weapons are kind of Weapons of Mass Destruction (WMD). They were used large quantities in WWI. Historically, large quantities usage like WWI was not recorded, but small usage has appeared now and then. Chemical weapons are so called "Nuclear weapon for poor countrys" because it's very easy to produce/possession being possible. They are categorized (1) Nerve Agents, (2) Blister Agents, (3) Cyanide (blood) Agents, (4) Pulmonary Agents, (5) Incapacitating Agents (6) Tear Agents from the viewpoint of human body interaction. In 1997 the Chemical Weapons Convention has taken effect. It prohibits chemical weapons development/production, and Organization for the Prohibition of Chemical Weapons (OPCW) verification regime contributes to the chemical weapons disposal. But possibility of possession/use of weapons of mass destruction by terrorist group represented in one by Matsumoto and Tokyo Subway Sarin Attack, So new chemical terrorism countermeasures are necessary.

  3. Dietary nutrients, additives, and fish health

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Disease outbreaks have become a major threat to the sustainability of the aquaculture industry, with antibiotics and chemicals historically used to treat animals ineffective or not allowed to be used today. In this book Dietary Nutrients, Additives, and Fish Health, the relationships between dietar...

  4. Additives in fibers and fabrics.

    PubMed

    Barker, R H

    1975-06-01

    The additives and contaminants which occur in textile fibers vary widely, depending on the type of fiber and the pretreatment which it has received. Synthetic fibers such as nylon and polyester contain trace amounts of contaminants such as catalysts and catalyst deactivators which remain after the synthesis of the basic polymers. In addition, there are frequently a number of materials which are added to perform specific functions in almost all man-made fibers. Examples of these would include traces of metals or metal salts used as tracers for identification of specific lots of fiber, TiO2 or similar materials added as delustrants, and a host of organic species added for such special purposes as antistatic agents or flame retardants. There may also be considerable quantities of residual monomer or small oligomers dissolved in the polymer matrix. The situation becomes even more complex after the fibers are converted into fabric form. Numerous materials are applied at various stages of fabric preparation to act as lubricants, sizing agents, antistats, bleaches, and wetting agents to facilitate the processing, but these are normally removed before the fabric reaches the cutters of the ultimate consumers and therefore usually do not constitute potential hazards. However, there are many other chemical agents which are frequently added during the later stages of fabric preparation and which are not designed to be removed. Aside from dyes and printing pigments, the most common additive for apparel fabrics is a durable press treatment. This generally involves the use of materials capable of crosslinking cellulosics by reacting through such functions as N-methylolated amides or related compounds such as ureas and carbamates. These materials pose some potential hazards due to both the nitrogenous bases and the formaldehyde which they usually release. There is usually also some residual catalyst in fabrics which have received such treatments. Other types of chemical treatments

  5. Additives in fibers and fabrics.

    PubMed Central

    Barker, R H

    1975-01-01

    The additives and contaminants which occur in textile fibers vary widely, depending on the type of fiber and the pretreatment which it has received. Synthetic fibers such as nylon and polyester contain trace amounts of contaminants such as catalysts and catalyst deactivators which remain after the synthesis of the basic polymers. In addition, there are frequently a number of materials which are added to perform specific functions in almost all man-made fibers. Examples of these would include traces of metals or metal salts used as tracers for identification of specific lots of fiber, TiO2 or similar materials added as delustrants, and a host of organic species added for such special purposes as antistatic agents or flame retardants. There may also be considerable quantities of residual monomer or small oligomers dissolved in the polymer matrix. The situation becomes even more complex after the fibers are converted into fabric form. Numerous materials are applied at various stages of fabric preparation to act as lubricants, sizing agents, antistats, bleaches, and wetting agents to facilitate the processing, but these are normally removed before the fabric reaches the cutters of the ultimate consumers and therefore usually do not constitute potential hazards. However, there are many other chemical agents which are frequently added during the later stages of fabric preparation and which are not designed to be removed. Aside from dyes and printing pigments, the most common additive for apparel fabrics is a durable press treatment. This generally involves the use of materials capable of crosslinking cellulosics by reacting through such functions as N-methylolated amides or related compounds such as ureas and carbamates. These materials pose some potential hazards due to both the nitrogenous bases and the formaldehyde which they usually release. There is usually also some residual catalyst in fabrics which have received such treatments. Other types of chemical treatments

  6. Chemical microsensors

    DOEpatents

    Li, DeQuan; Swanson, Basil I.

    1995-01-01

    An article of manufacture is provided including a substrate having an oxide surface layer and a selective thin film of a cyclodextrin derivative chemically bound upon said substrate, said film is adapted for the inclusion of a selected organic compound therewith. Such an article can be either a chemical sensor capable of detecting a resultant mass change from inclusion of the selected organic compound or a chemical separator capable of reversibly selectively separating a selected organic compound.

  7. Determination of the chemical structures of tandyukisins B-D, isolated from a marine sponge-derived fungus.

    PubMed

    Yamada, Takeshi; Umebayashi, Yoshihide; Kawashima, Maiko; Sugiura, Yuma; Kikuchi, Takashi; Tanaka, Reiko

    2015-05-01

    Tandyukisins B-D (1-3), novel decalin derivatives, have been isolated from a strain of Trichoderma harzianum OUPS-111D-4 originally derived from the marine sponge Halichondria okadai, and their structures have been elucidated on the basis of spectroscopic analyses using 1D and 2D NMR techniques. In addition, their chemical structures were established by chemical transformation. They exhibited weak cytotoxicity, but selective growth inhibition on panel screening using 39 human cancer cell lines. PMID:26006715

  8. Performance Boosting Additive

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Mainstream Engineering Corporation was awarded Phase I and Phase II contracts from Goddard Space Flight Center's Small Business Innovation Research (SBIR) program in early 1990. With support from the SBIR program, Mainstream Engineering Corporation has developed a unique low cost additive, QwikBoost (TM), that increases the performance of air conditioners, heat pumps, refrigerators, and freezers. Because of the energy and environmental benefits of QwikBoost, Mainstream received the Tibbetts Award at a White House Ceremony on October 16, 1997. QwikBoost was introduced at the 1998 International Air Conditioning, Heating, and Refrigeration Exposition. QwikBoost is packaged in a handy 3-ounce can (pressurized with R-134a) and will be available for automotive air conditioning systems in summer 1998.

  9. Sewage sludge additive

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J. J.; Mueller, W. A.; Ingham, J. D. (Inventor)

    1980-01-01

    The additive is for a raw sewage treatment process of the type where settling tanks are used for the purpose of permitting the suspended matter in the raw sewage to be settled as well as to permit adsorption of the dissolved contaminants in the water of the sewage. The sludge, which settles down to the bottom of the settling tank is extracted, pyrolyzed and activated to form activated carbon and ash which is mixed with the sewage prior to its introduction into the settling tank. The sludge does not provide all of the activated carbon and ash required for adequate treatment of the raw sewage. It is necessary to add carbon to the process and instead of expensive commercial carbon, coal is used to provide the carbon supplement.

  10. Perspectives on Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Bourell, David L.

    2016-07-01

    Additive manufacturing (AM) has skyrocketed in visibility commercially and in the public sector. This article describes the development of this field from early layered manufacturing approaches of photosculpture, topography, and material deposition. Certain precursors to modern AM processes are also briefly described. The growth of the field over the last 30 years is presented. Included is the standard delineation of AM technologies into seven broad categories. The economics of AM part generation is considered, and the impacts of the economics on application sectors are described. On the basis of current trends, the future outlook will include a convergence of AM fabricators, mass-produced AM fabricators, enabling of topology optimization designs, and specialization in the AM legal arena. Long-term developments with huge impact are organ printing and volume-based printing.

  11. Sarks as additional fermions

    NASA Astrophysics Data System (ADS)

    Agrawal, Jyoti; Frampton, Paul H.; Jack Ng, Y.; Nishino, Hitoshi; Yasuda, Osamu

    1991-03-01

    An extension of the standard model is proposed. The gauge group is SU(2) X ⊗ SU(3) C ⊗ SU(2) S ⊗ U(1) Q, where all gauge symmetries are unbroken. The colour and electric charge are combined with SU(2) S which becomes strongly coupled at approximately 500 GeV and binds preons to form fermionic and vector bound states. The usual quarks and leptons are singlets under SU(2) X but additional fermions, called sarks. transform under it and the electroweak group. The present model explains why no more than three light quark-lepton families can exist. Neutral sark baryons, called narks, are candidates for the cosmological dark matter having the characteristics designed for WIMPS. Further phenomenological implications of sarks are analyzed i including electron-positron annihilation. Z 0 decay, flavor-changing neutral currents. baryon-number non-conservation, sarkonium and the neutron electric dipole moment.

  12. Chemical sensors

    DOEpatents

    Lowell, J.R. Jr.; Edlund, D.J.; Friesen, D.T.; Rayfield, G.W.

    1991-07-02

    Sensors responsive to small changes in the concentration of chemical species are disclosed. The sensors comprise a mechanochemically responsive polymeric film capable of expansion or contraction in response to a change in its chemical environment. They are operatively coupled to a transducer capable of directly converting the expansion or contraction to a measurable electrical response. 9 figures.

  13. Chemical Peels

    MedlinePlus

    ... the complications or potential side effects of a chemical peel? Temporary or permanent change in skin color, particularly for women on birth control pills, who subsequently become pregnant or have a history of brownish facial ... after having a chemical peel? All peels require some follow-up care: ...

  14. Chemical preconcentrator

    DOEpatents

    Manginell, Ronald P.; Frye-Mason, Gregory C.

    2001-01-01

    A chemical preconcentrator is disclosed with applications to chemical sensing and analysis. The preconcentrator can be formed by depositing a resistive heating element (e.g. platinum) over a membrane (e.g. silicon nitride) suspended above a substrate. A coating of a sorptive material (e.g. a microporous hydrophobic sol-gel coating or a polymer coating) is formed on the suspended membrane proximate to the heating element to selective sorb one or more chemical species of interest over a time period, thereby concentrating the chemical species in the sorptive material. Upon heating the sorptive material with the resistive heating element, the sorbed chemical species are released for detection and analysis in a relatively high concentration and over a relatively short time period. The sorptive material can be made to selectively sorb particular chemical species of interest while not substantially sorbing other chemical species not of interest. The present invention has applications for use in forming high-sensitivity, rapid-response miniaturized chemical analysis systems (e.g. a "chem lab on a chip").

  15. Chemical sensors

    DOEpatents

    Lowell, Jr., James R.; Edlund, David J.; Friesen, Dwayne T.; Rayfield, George W.

    1991-01-01

    Sensors responsive to small changes in the concentration of chemical species are disclosed, comprising (a) a mechanochemically responsive polymeric film capable of expansion or contraction in response to a change in its chemical environment, operatively coupled to (b) a transducer capable of directly converting said expansion or contraction to a measurable electrical response.

  16. Chemical Emergencies

    MedlinePlus

    ... agents such as sarin and VX. Many hazardous chemicals are used in industry - for example, chlorine, ammonia, and benzene. Some can be made from everyday items such as household cleaners. Although there are no guarantees of safety during a chemical emergency, you can take actions to protect yourself. ...

  17. Chemical threats.

    PubMed

    Fry, Donald E

    2006-06-01

    The use of chemical agents as military weapons has been recognized for many centuries but reached the most feared and publicized level during World War I. Considerable political effort has been exercised in the twentieth century to restrict military strategies with chemicals. However, considerable concern currently exists that chemical weapons may be used as agents in civilian terrorism. The distribution of acetaminophen tablets contaminated with potassium cyanide and the release of sarin in the Tokyo sub-way system show that larger-scale deployment of chemical agents can be a reality. This reality makes it necessary for civilian disaster-planning strategies to incorporate an understanding of chemical agents, their effects, and the necessary treatment.

  18. Microcalibrator system for chemical signature and reagent delivery.

    SciTech Connect

    Staton, Alan W.; Simonson, Robert Joseph; Adkins, Douglas Ray; Rawlinson, Kim Scott; Robinson, Alex Lockwood; Hance, Bradley G.; Manginell, Ronald Paul; Sanchez, Lawrence James; Ellison, Jennifer Anne; Sokolowski, Sara Suzette

    2005-03-01

    Networked systems of low-cost, small, integrable chemical sensors will enable monitoring of Nonproliferation and Materials Control targets and chemical weapons threats. Sandia-designed prototype chemical sensor systems are undergoing extended field testing supported by DOE and other government agencies. A required surety component will be verification of microanalytical system performance, which can be achieved by providing a programmable source of chemical signature(s) for autonomous calibration of analytical systems. In addition, such a controlled chemical source could be used to dispense microaliquots of derivatization reagents, extending the analysis capability of chemical sensors to a wider range of targets. We have developed a microfabricated system for controlled release of selected compounds (calibrants) into the analytical stream of microsensor systems. To minimize pumping and valve requirements of microfluidic systems, and to avoid degradation issues associated with storage of dilute solutions, we have utilized thermally labile organic salts as solid-phase reservoir materials. Reproducible deposition of tetrapropyl ammonium hydroxide onto arrays of microfabricated heating elements can provide a pair of calibration marker compounds (one fast and one slow-eluting compound) for GC analyses. The use of this microaliquot gas source array for hydrogen generation is currently under further development. The goal of the latter effort will be to provide a source of high-pressure, low viscosity GC carrier gas for Sandia's next-generation microfabricated gas-phase chemical analysis systems.

  19. Infrared Spectroscopy as a Chemical Fingerprinting Tool

    NASA Technical Reports Server (NTRS)

    Huff, Timothy L.

    2003-01-01

    Infrared (IR) spectroscopy is a powerful analytical tool in the chemical fingerprinting of materials. Any sample material that will interact with infrared light produces a spectrum and, although normally associated with organic materials, inorganic compounds may also be infrared active. The technique is rapid, reproducible and usually non-invasive to the sample. That it is non-invasive allows for additional characterization of the original material using other analytical techniques including thermal analysis and RAMAN spectroscopic techniques. With the appropriate accessories, the technique can be used to examine samples in liquid, solid or gas phase. Both aqueous and non-aqueous free-flowing solutions can be analyzed, as can viscous liquids such as heavy oils and greases. Solid samples of varying sizes and shapes may also be examined and with the addition of microscopic IR (microspectroscopy) capabilities, minute materials such as single fibers and threads may be analyzed. With the addition of appropriate software, microspectroscopy can be used for automated discrete point or compositional surface area mapping, with the latter providing a means to record changes in the chemical composition of a material surface over a defined area. Due to the ability to characterize gaseous samples, IR spectroscopy can also be coupled with thermal processes such as thermogravimetric (TG) analyses to provide both thermal and chemical data in a single run. In this configuration, solids (or liquids) heated in a TG analyzer undergo decomposition, with the evolving gases directed into the IR spectrometer. Thus, information is provided on the thermal properties of a material and the order in which its chemical constituents are broken down during incremental heating. Specific examples of these varied applications will be cited, with data interpretation and method limitations further discussed.

  20. NOx analyser interefence from alkenes

    NASA Astrophysics Data System (ADS)

    Bloss, W. J.; Alam, M. S.; Lee, J. D.; Vazquez, M.; Munoz, A.; Rodenas, M.

    2012-04-01

    Nitrogen oxides (NO and NO2, collectively NOx) are critical intermediates in atmospheric chemistry. NOx abundance controls the levels of the primary atmospheric oxidants OH, NO3 and O3, and regulates the ozone production which results from the degradation of volatile organic compounds. NOx are also atmospheric pollutants in their own right, and NO2 is commonly included in air quality objectives and regulations. In addition to their role in controlling ozone formation, NOx levels affect the production of other pollutants such as the lachrymator PAN, and the nitrate component of secondary aerosol particles. Consequently, accurate measurement of nitrogen oxides in the atmosphere is of major importance for understanding our atmosphere. The most widely employed approach for the measurement of NOx is chemiluminescent detection of NO2* from the NO + O3 reaction, combined with NO2 reduction by either a heated catalyst or photoconvertor. The reaction between alkenes and ozone is also chemiluminescent; therefore alkenes may contribute to the measured NOx signal, depending upon the instrumental background subtraction cycle employed. This interference has been noted previously, and indeed the effect has been used to measure both alkenes and ozone in the atmosphere. Here we report the results of a systematic investigation of the response of a selection of NOx analysers, ranging from systems used for routine air quality monitoring to atmospheric research instrumentation, to a series of alkenes ranging from ethene to the biogenic monoterpenes, as a function of conditions (co-reactants, humidity). Experiments were performed in the European Photoreactor (EUPHORE) to ensure common calibration, a common sample for the monitors, and to unequivocally confirm the alkene (via FTIR) and NO2 (via DOAS) levels present. The instrument responses ranged from negligible levels up to 10 % depending upon the alkene present and conditions used. Such interferences may be of substantial importance