WorldWideScience

Sample records for inorganic sulfur compounds

  1. Microbiological disproportionation of inorganic sulfur compounds

    DEFF Research Database (Denmark)

    Finster, Kai

    2008-01-01

    The disproportionation of inorganic sulfur intermediates at moderate temperatures (0-80 °C) is a microbiologically catalyzed chemolithotrophic process in which compounds like elemental sulfur, thiosulfate, and sulfite serve as both electron donor and acceptor, and generate hydrogen sulfide and su...

  2. Oxidation of inorganic sulfur compounds in acidophilic prokaryotes

    Energy Technology Data Exchange (ETDEWEB)

    Rohwerder, T.; Sand, W. [Universitaet Duisburg-Essen, Biofilm Centre, Aquatic Biotechnology, Duisburg (Germany)

    2007-07-15

    The oxidation of reduced inorganic sulfur compounds to sulfuric acid is of great importance for biohydrometallurgical technologies as well as the formation of acidic (below pH 3) and often heavy metal-contaminated environments. The use of elemental sulfur as an electron donor is the predominant energy-yielding process in acidic natural sulfur-rich biotopes but also at mining sites containing sulfidic ores. Contrary to its significant role in the global sulfur cycle and its biotechnological importance, the microbial fundamentals of acidophilic sulfur oxidation are only incompletely understood. Besides giving an overview of sulfur-oxidizing acidophiles, this review describes the so far known enzymatic reactions related to elemental sulfur oxidation in acidophilic bacteria and archaea. Although generally similar reactions are employed in both prokaryotic groups, the stoichiometry of the key enzymes is different. Bacteria oxidize elemental sulfur by a sulfur dioxygenase to sulfite whereas in archaea, a sulfur oxygenase reductase is used forming equal amounts of sulfide and sulfite. In both cases, the activation mechanism of elemental sulfur is not known but highly reactive linear sulfur forms are assumed to be the actual substrate. Inhibition as well as promotion of these biochemical steps is highly relevant in bioleaching operations. An efficient oxidation can prevent the formation of passivating sulfur layers. In other cases, a specific inhibition of sulfur biooxidation may be beneficial for reducing cooling and neutralization costs. In conclusion, the demand for a better knowledge of the biochemistry of sulfur-oxidizing acidophiles is underlined. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

  3. Sulfur Isotope Exchange between S-35 Labeled Inorganic Sulfur-Compounds in Anoxic Marine-Sediments

    DEFF Research Database (Denmark)

    FOSSING, H.; THODEANDERSEN, S.; JØRGENSEN, BB

    1992-01-01

    of isotope exchange, specific radioactivities of the reduced sulfur pools were poorly defined and could not be used to calculate their rates of formation. Such isotope exchange reactions between the reduced inorganic sulfur compounds will affect the stable isotope distribution and are expected to decrease...

  4. Sulfur Isotope Exchange between S-35 Labeled Inorganic Sulfur-Compounds in Anoxic Marine-Sediments

    DEFF Research Database (Denmark)

    FOSSING, H.; THODEANDERSEN, S.; JØRGENSEN, BB

    1992-01-01

    Isotope exchange reactions between S-35-labeled sulfur compounds were studied in anoxic estuarine sediment slurries at 21-degrees-C and pH 7.4-7.7. Two experiments labeled with radioactive elemental sulfur (S-35-degrees) and one labeled with radioactive sulfate ((SO42-)-S-35) were performed as time......% of the total S-35 was recovered in the SIGMA-HS- pool in less than 1.5 h. With no detectable SIGMA-HS- (less than 1-mu-M) in the slurry, 58% of the total S-35 was observed in the pyrite pool within 1.5 h. The FeS pool received up to 31% of all S-35 added. The rapid S-35 incorporation from S-35-degrees...... into SIGMA-HS- and FeS pools was explained by isotope exchange reactions. In contrast, there was evidence that the radioactivity observed in the 'pyrite pool' was caused by adhesion of the added S-35-degrees to the FeS2 grains. In all S-35-degrees-labeled experiments we also observed oxidation...

  5. Development of techniques of production of sulfur-35 and its inorganic compounds

    International Nuclear Information System (INIS)

    Shikata, Eiji

    1981-12-01

    Techniques to produce routinely Curies of carrier-free sulfur-35 from neutron irradiated potassium chloride were developed. Firstly the ratio of sulfur-35 to phosphorus-32 produced respectively by the reactions 35 Cl(n,p) 35 S and 35 Cl(n,α) 32 P was determined. For the post-irradiation process, two processes of anion exchange and cation exchange were studied. The former process was based on the selective elution of carrier-free sulfate after precipitation of the bulk of potassium chloride by ethanol and the latter process on the selective adsorption of carrier-free phosphate on Fe +3 -cation exchange resin. A gloved box with various appendant equipments was constructed for routine production and a glass apparatus was installed in it. Sulfur-35 from 1 Ci to 5 Ci has been produced by the cation exchange process several times every year during past few years, and products of high quality have been obtained with yields higher than 90% without any troubles. In the studies on the synthesis of sulfur-35 labeled inorganic compounds, sulfate[ 35 S] was reduced with tin(II)-phosphoric acid to hydrogen sulfide[ 35 S], which was oxidized to elementary sulfur[ 35 S]. Sulfate[ 35 S] of sodium or copper(II) was precipitated from an aqueous solution of sodium or copper(II) chloride containing carrier-free sulfate [ 35 S] by adding carrier of either one of the sulfates and ethanol. Copper(II) sulfate[ 35 S] was pyrolyzed to evolve sulfur[ 35 S] dioxide, which was fixed in a sodium hydroxide solution as sodium sulfite[ 35 S]. This was allowed to react with colloidal sulfur in a boiling solution in the presence of 2-octanol to form thiosulfate[ 35 S] efficiently. By treating target potassium chloride before and after irradiation in an oxygen-free atmosphere, approximately 60% of sulfur-35 was recovered as thiosulfate. Reduction with nascent hydrogen and decomposition with acid of the thiosulfate were studied to prepare elementary sulfur [ 35 S]. (author)

  6. The transformation of inorganic sulfur compounds and the assimilation of organic and inorganic carbon by the sulfur disproportionating bacterium Desulfocapsa sulfoexigens.

    Science.gov (United States)

    Frederiksen, Trine-Maria; Finster, Kai

    2004-02-01

    The physiology of the sulfur disproportionator Desulfocapsa sulfoexigens was investigated in batch cultures and in a pH-regulated continuously flushed fermentor system. It was shown that a sulphide scavanger in the form of ferric iron was not obligatory and that the control of pH allowed production of more biomass than was possible in carbonate buffered but unregulated batch cultures. Small amounts of sulphite were produced during disproportionation of elemental sulfur and thiosulphate. In addition, it was shown that in the presence of hydrogen, a respiratory type of process is favored before the disproportionation of sulphite, thiosulphate and elemental sulfur. Sulphate reduction was not observed. D. sulfoexigens assimilated inorganic carbon even in the presence of organic carbon sources. Inorganic carbon assimilation was probably catalyzed by the reverse CO-dehydrogenase pathway, which was supported by the constitutive expression of the gene encoding CO-dehydrogenase in cultures grown in the presence of acetate and by the high carbon fractionation values that are indicative of this pathway.

  7. Complete genome sequence of Desulfocapsa sulfexigens, a marine deltaproteobacterium specialized in disproportionating inorganic sulfur compounds.

    Science.gov (United States)

    Finster, Kai Waldemar; Kjeldsen, Kasper Urup; Kube, Michael; Reinhardt, Richard; Mussmann, Marc; Amann, Rudolf; Schreiber, Lars

    2013-04-15

    Desulfocapsa sulfexigens SB164P1 (DSM 10523) belongs to the deltaproteobacterial family Desulfobulbaceae and is one of two validly described members of its genus. This strain was selected for genome sequencing, because it is the first marine bacterium reported to thrive on the disproportionation of elemental sulfur, a process with a unresolved enzymatic pathway in which elemental sulfur serves both as electron donor and electron acceptor. Furthermore, in contrast to its phylogenetically closest relatives, which are dissimilatory sulfate-reducers, D. sulfexigens is unable to grow by sulfate reduction and appears metabolically specialized in growing by disproportionating elemental sulfur, sulfite or thiosulfate with CO2 as the sole carbon source. The genome of D. sulfexigens contains the set of genes that is required for nitrogen fixation. In an acetylene assay it could be shown that the strain reduces acetylene to ethylene, which is indicative for N-fixation. The circular chromosome of D. sulfexigens SB164P1 comprises 3,986,761 bp and harbors 3,551 protein-coding genes of which 78% have a predicted function based on auto-annotation. The chromosome furthermore encodes 46 tRNA genes and 3 rRNA operons.

  8. Molecular modeling of inorganic compounds

    National Research Council Canada - National Science Library

    Comba, Peter; Hambley, Trevor W; Martin, Bodo

    2009-01-01

    ... mechanics to inorganic and coordination compounds. Initially, simple metal complexes were modeled, but recently the field has been extended to include organometallic compounds, catalysis and the interaction of metal ions with biological macromolecules. The application of molecular mechanics to coordination compounds is complicated by the numbe...

  9. Nomenclature on an inorganic compound

    International Nuclear Information System (INIS)

    1998-10-01

    This book contains eleven chapters : which mention nomenclature of an inorganic compound with introduction and general principle on nomenclature of compound. It gives the description of grammar for nomenclature such as brackets, diagonal line, asterisk, and affix, element, atom and groups of atom, chemical formula, naming by stoichiometry, solid, neutral molecule compound, ion, a substituent, radical and name of salt, oxo acid and anion on introduction and definition of oxo acid, coordination compound like symbol of stereochemistry , boron and hydrogen compound and related compound.

  10. Inorganic, coordination and organometallic compounds

    International Nuclear Information System (INIS)

    Jursik, F.

    1978-01-01

    Separation of cations and anions of inorganic, coordination and metalloorganic compounds by the method of liquid column chromatography is considered. Common scheme of multicomponent cation mixture is suggesteed. Separation conditions, adsrbents, eluents, pH value solution concenstration, elution rate are also suggested. Separation of rare earth elements Cs, Be, Cd, Te, Th, U, Mo, Re, V, Ru, Zr, In compounds is considered as an example of liquid column chromatography application. Data on column chromatography application are summarized in a table

  11. The Global Redox Responding RegB/RegA Signal Transduction System Regulates the Genes Involved in Ferrous Iron and Inorganic Sulfur Compound Oxidation of the Acidophilic Acidithiobacillus ferrooxidans

    Directory of Open Access Journals (Sweden)

    Danielle Moinier

    2017-07-01

    Full Text Available The chemical attack of ore by ferric iron and/or sulfuric acid releases valuable metals. The products of these reactions are recycled by iron and sulfur oxidizing microorganisms. These acidophilic chemolithotrophic prokaryotes, among which Acidithiobacillus ferrooxidans, grow at the expense of the energy released from the oxidation of ferrous iron and/or inorganic sulfur compounds (ISCs. In At. ferrooxidans, it has been shown that the expression of the genes encoding the proteins involved in these respiratory pathways is dependent on the electron donor and that the genes involved in iron oxidation are expressed before those responsible for ISCs oxidation when both iron and sulfur are present. Since the redox potential increases during iron oxidation but remains stable during sulfur oxidation, we have put forward the hypothesis that the global redox responding two components system RegB/RegA is involved in this regulation. To understand the mechanism of this system and its role in the regulation of the aerobic respiratory pathways in At. ferrooxidans, the binding of different forms of RegA (DNA binding domain, wild-type, unphosphorylated and phosphorylated-like forms of RegA on the regulatory region of different genes/operons involved in ferrous iron and ISC oxidation has been analyzed. We have shown that the four RegA forms are able to bind specifically the upstream region of these genes. Interestingly, the phosphorylation of RegA did not change its affinity for its cognate DNA. The transcriptional start site of these genes/operons has been determined. In most cases, the RegA binding site(s was (were located upstream from the −35 (or −24 box suggesting that RegA does not interfere with the RNA polymerase binding. Based on the results presented in this report, the role of the RegB/RegA system in the regulation of the ferrous iron and ISC oxidation pathways in At. ferrooxidans is discussed.

  12. The Global Redox Responding RegB/RegA Signal Transduction System Regulates the Genes Involved in Ferrous Iron and Inorganic Sulfur Compound Oxidation of the Acidophilic Acidithiobacillus ferrooxidans

    Science.gov (United States)

    Moinier, Danielle; Byrne, Deborah; Amouric, Agnès; Bonnefoy, Violaine

    2017-01-01

    The chemical attack of ore by ferric iron and/or sulfuric acid releases valuable metals. The products of these reactions are recycled by iron and sulfur oxidizing microorganisms. These acidophilic chemolithotrophic prokaryotes, among which Acidithiobacillus ferrooxidans, grow at the expense of the energy released from the oxidation of ferrous iron and/or inorganic sulfur compounds (ISCs). In At. ferrooxidans, it has been shown that the expression of the genes encoding the proteins involved in these respiratory pathways is dependent on the electron donor and that the genes involved in iron oxidation are expressed before those responsible for ISCs oxidation when both iron and sulfur are present. Since the redox potential increases during iron oxidation but remains stable during sulfur oxidation, we have put forward the hypothesis that the global redox responding two components system RegB/RegA is involved in this regulation. To understand the mechanism of this system and its role in the regulation of the aerobic respiratory pathways in At. ferrooxidans, the binding of different forms of RegA (DNA binding domain, wild-type, unphosphorylated and phosphorylated-like forms of RegA) on the regulatory region of different genes/operons involved in ferrous iron and ISC oxidation has been analyzed. We have shown that the four RegA forms are able to bind specifically the upstream region of these genes. Interestingly, the phosphorylation of RegA did not change its affinity for its cognate DNA. The transcriptional start site of these genes/operons has been determined. In most cases, the RegA binding site(s) was (were) located upstream from the −35 (or −24) box suggesting that RegA does not interfere with the RNA polymerase binding. Based on the results presented in this report, the role of the RegB/RegA system in the regulation of the ferrous iron and ISC oxidation pathways in At. ferrooxidans is discussed. PMID:28747899

  13. Medicinal Uses of Inorganic Compounds - 2

    Indian Academy of Sciences (India)

    In the first part of this article, we described medicinal uses of inorganic compounds relating to cancer care, infection and diabetic control, neurological, cardiovascular and in- flammatory diseases. This article contains further infor- mation on the medicinal uses of inorganic compounds as therapeutic and diagnostic in ...

  14. Biogenic sulfur compounds and the global sulfur cycle

    International Nuclear Information System (INIS)

    Aneja, V.P.; Aneja, A.P.; Adams, D.F.

    1982-01-01

    Field measurements of biogenic sulfur compounds shows a great variation in concentrations and emission rates for H 2 S, DMS, CS 2 and COS. Measurements by the chamber method and estimates from micrometeorological sampling are employed to determine the earth-atmosphere flux of these gases. Much of the variation can be attributed to differences of climate and surface conditions, with marshes being a large source of biogenic sulfur (mean contribution 4 x 10 to the 6th ton/year maximum contribution 142 x 10 to the 6th ton/year). Considering that the estimated biogenic contribution needed to balance the global sulfur cycle ranges from 40- 230 x 10 to the 6th tons/year, the mean values are not sufficient to balance this cycle. Further experimental investigations are suggested in order to characterize the biogenic processes adequately

  15. Behaviour of organic sulfur compounds in HPLC

    International Nuclear Information System (INIS)

    Freyholdt, T.

    1982-01-01

    The retention behaviour of organic sulfur compounds in the reverse-bonded-phase chromatography is characterized by determining the retention indices according to Kovats. The results of these studies show that the solubility of organic compounds in the eluting agent and the molar sorption surfaces of the solutes are the main factors determining the retention behaviour. Knowledge of the retention indices of above-mentioned compounds allows a quick interpretation of chromatograms obtained through a product analysis of γ-irradiated aqueous solutions of organic sulfur compounds. Dithia compounds of the type CH 3 -S-(CH 2 )sub(n)-S-Ch 3 (1 1. 2,4-Dithiapentane (n = 1) however will yield primarily monothio-S-methyl formate as a stable end product. The formation of oxygenic reaction products proceeds via sulfur-centred radical kations. Spin trapping experiments with nitroxyl radicals show that it is possible to trap radiation-chemically produced radicals of sulfurous substrates, but the thus obtained adducts with half-life periods of 4-5 min. cannot be identified by means of NMR, IR or mass spectroscopy. (orig.) [de

  16. Intercalation compounds involving inorganic layered structures

    Directory of Open Access Journals (Sweden)

    CONSTANTINO VERA R. L.

    2000-01-01

    Full Text Available Two-dimensional inorganic networks can shown intracrystalline reactivity, i.e., simple ions, large species as Keggin ions, organic species, coordination compounds or organometallics can be incorporated in the interlayer region. The host-guest interaction usually causes changes in their chemical, catalytic, electronic and optical properties. The isolation of materials with interesting properties and making use of soft chemistry routes have given rise the possibility of industrial and technological applications of these compounds. We have been using several synthetic approaches to intercalate porphyrins and phthalocyanines into inorganic materials: smectite clays, layered double hydroxides and layered niobates. The isolated materials have been characterized by elemental and thermal analysis, X-ray diffraction, surface area measurements, scanning electronic microscopy, electronic and resonance Raman spectroscopies and EPR. The degree of layer stacking and the charge density of the matrices as well their acid-base nature were considered in our studies on the interaction between the macrocycles and inorganic hosts.

  17. Volatile sulfur compounds in tropical fruits

    Directory of Open Access Journals (Sweden)

    Robert J. Cannon

    2018-04-01

    Full Text Available Global production and demand for tropical fruits continues to grow each year as consumers are enticed by the exotic flavors and potential health benefits that these fruits possess. Volatile sulfur compounds (VSCs are often responsible for the juicy, fresh aroma of tropical fruits. This poses a challenge for analytical chemists to identify these compounds as most often VSCs are found at low concentrations in most tropical fruits. The aim of this review is to discuss the extraction methods, enrichment techniques, and instrumentation utilized to identify and quantify VSCs in natural products. This will be followed by a discussion of the VSCs reported in tropical and subtropical fruits, with particular attention to the odor and taste attributes of each compound. Finally, the biogenesis and enzymatic formation of specific VSCs in tropical fruits will be highlighted along with the contribution each possesses to the aroma of their respective fruit. Keywords: Tropical fruits, Volatile sulfur compounds, Extraction methods

  18. Role of sulfate reduction in long term accumulation of organic and inorganic sulfur in lake sediments

    International Nuclear Information System (INIS)

    Rudd, J.W.M.; Kelly, C.A.; Furutani, A.

    1986-01-01

    Sulfate reduction and the accumulation of reduced sulfur in epilimnetic sediments were studied in lakes in southern Norway, the Adirondack Mountains, and at the Experimental Lakes Area (ELA) of northwestern Ontario. In all of the lakes, sulfate reduction produced substantial quantities of pyrite and organic sulfur compounds. In 9-month in situ experiments at ELA using 35 S, there was a large loss (55%) with time of the S initially reduced and deposited in the sediments and a preferential loss of inorganic S compounds which led to a predominance of organic 35 S accumulation in the sediments. An intensive study of long term accumulation of sulfur in the epilimnetic sediments of four Adirondack lakes also showed that the most important long term end product of sulfate reduction was organic S and that sulfate reduction was the major source of S to the sediments. Because of high concentrations of iron in all of the sediments samples and because of the long term storage of sulfur in sediments, mostly as organic S, iron did not limit iron sulfide accumulation in these sediments. Iron limitation is unlikely to occur except in unusual circumstances. This study indicates that formation of organic S in epilimnetic sediments is primarily responsible for H + consumption via sulfate reduction in acidified lakes

  19. Combined removal of sulfur compounds and nitrate by autotrophic denitrication in bioaugmented activated sludge system

    NARCIS (Netherlands)

    Manconi, I.; Carucci, A.; Lens, P.N.L.

    2007-01-01

    An autotrophic denitrification process using reduced sulfur compounds (thiosulfate and sulfide) as electron donor in an activated sludge system is proposed as an efficient and cost effective alternative to conventional heterotrophic denitrification for inorganic (or with low C/N ratio) wastewaters

  20. Volatile Sulfur Compounds from Livestock Production

    DEFF Research Database (Denmark)

    Kasper, Pernille

    . Presently, the development of abatement technologies is limited by the lack of an accurate and reliable method for quantifying the effect on odor. To measure the impact of air cleaning techniques on perceived odor, common practice in Europe is to store odor samples in sample bags and quantify them......Volatile sulfur compounds, i.e. hydrogen sulfide, methanethiol and dimethyl sulfide have been identified as key odorants in livestock production due to their high concentration levels and low odor threshold values. At the same time their removal with abatement technologies based on mass transfer...... from a gas phase to a liquid phase, e.g. biotrickling filters, is decelerated due to their low partitioning coefficients. This can significantly limit the odor reduction obtained with these technologies. The present study examines the possibility of adding metal catalysts to enhance the mass transfer...

  1. Investigations on organogermanium compounds XII. Reactions of trialkylgermylalkalimetal compounds in hexamethylphosphoric triamide (HMPT) with some inorganic and organic compounds

    NARCIS (Netherlands)

    Bulten, E.J.; Noltes, J.G.

    1971-01-01

    Trialkylgermyl alkali metal compounds in HMPT have been found to be highly reactive nucleophiles. Reactions with some inorganic and organic compounds, such as oxygen, carbon dioxide, inorganic and orgaanic halides, aldehydes, ketones, epoxides and lactones are described. Several new

  2. Multiple-heteroatom-containing sulfur compounds in a high sulfur coal

    International Nuclear Information System (INIS)

    Winans, R.E.; Neill, P.H.

    1990-01-01

    Flash vacuum pyrolysis of a high sulfur coal has been combined with high resolution mass spectrometry yielding information on aromatic sulfur compounds containing an additional heteroatom. Sulfur emission from coal utilization is a critical problem and in order to devise efficient methods for removing organic sulfur, it is important to know what types of molecules contain sulfur. A high sulfur Illinois No. 6 bituminous coal (Argonne Premium Coal Sample No. 3) was pyrolyzed on a platinum grid using a quartz probe inserted into a modified all glass heated inlet system and the products characterized by high resolution mass spectrometry (HRMS). A significant number of products were observed which contained both sulfur and an additional heteroatom. In some cases two additional heteroatoms were observed. These results are compared to those found in coal extracts and liquefaction products

  3. Sulfur-centered reactive intermediates derived from the oxidation of sulfur compounds of biological interest

    Energy Technology Data Exchange (ETDEWEB)

    Abedinzadeh, Z. [Lab. de Chimie Physique, UMR, Univ. Rene Descartes, Paris (France)

    2001-02-01

    Sulphur compounds play a central role in the structure and activity of many vital systems. In the living cell, sulfur constitutes an essential part of the defense against oxidative damage and is transformed into a variety of sulfur free radical species. Many studies of the chemistry of sulfur-centered radicals using pulse radiolysis and photolysis techniques to detect and measure the kinetics of these radicals have been published and reviewed. This paper discusses the present state of research on the formation and reactivity of certain sulfur-centered radicals [RS{sup .}, RSS{sup .}, RS{sup .+}, (RSSR){sup .+}] and their implications for biological systems. (author)

  4. Sulfur-centered reactive intermediates derived from the oxidation of sulfur compounds of biological interest

    International Nuclear Information System (INIS)

    Abedinzadeh, Z.

    2001-01-01

    Sulphur compounds play a central role in the structure and activity of many vital systems. In the living cell, sulfur constitutes an essential part of the defense against oxidative damage and is transformed into a variety of sulfur free radical species. Many studies of the chemistry of sulfur-centered radicals using pulse radiolysis and photolysis techniques to detect and measure the kinetics of these radicals have been published and reviewed. This paper discusses the present state of research on the formation and reactivity of certain sulfur-centered radicals [RS . , RSS . , RS .+ , (RSSR) .+ ] and their implications for biological systems. (author)

  5. Biodesulfurization of refractory organic sulfur compounds in fossil fuels.

    Science.gov (United States)

    Soleimani, Mehran; Bassi, Amarjeet; Margaritis, Argyrios

    2007-01-01

    The stringent new regulations to lower sulfur content in fossil fuels require new economic and efficient methods for desulfurization of recalcitrant organic sulfur. Hydrodesulfurization of such compounds is very costly and requires high operating temperature and pressure. Biodesulfurization is a non-invasive approach that can specifically remove sulfur from refractory hydrocarbons under mild conditions and it can be potentially used in industrial desulfurization. Intensive research has been conducted in microbiology and molecular biology of the competent strains to increase their desulfurization activity; however, even the highest activity obtained is still insufficient to fulfill the industrial requirements. To improve the biodesulfurization efficiency, more work is needed in areas such as increasing specific desulfurization activity, hydrocarbon phase tolerance, sulfur removal at higher temperature, and isolating new strains for desulfurizing a broader range of sulfur compounds. This article comprehensively reviews and discusses key issues, advances and challenges for a competitive biodesulfurization process.

  6. Medicinal Uses of Inorganic Compounds - 1

    Indian Academy of Sciences (India)

    Worldwide sales of inorganic drugs are growing rapidly. Although about 26 elements in the periodic table are considered essential for mammalian life, both ... Lithium like alcohol can influence mood. Lithium drugs such as lithium carbonate Li2C03. , are used for the treatment of manic-depressive disorders, most likely ...

  7. Binary systems solubilities of inorganic and organic compounds

    CERN Document Server

    Stephen, H

    1963-01-01

    Solubilities of Inorganic and Organic Compounds, Volume 1: Binary Systems, Part 1 is part of an approximately 5,500-page manual containing a selection from the International Chemical Literature on the Solubilities of Elements, Inorganic Compounds, Metallo-organic and Organic Compounds in Binary, Ternary and Multi-component Systems. A careful survey of the literature in all languages by a panel of scientists specially appointed for the task by the U.S.S.R. Academy of Sciences, Moscow, has made the compilation of this work possible. The complete English edition in five separately bound volumes w

  8. Improving rubber concrete by waste organic sulfur compounds.

    Science.gov (United States)

    Chou, Liang-Hisng; Lin, Chun-Nan; Lu, Chun-Ku; Lee, Cheng-Haw; Lee, Maw-Tien

    2010-01-01

    In this study, the use of crumb tyres as additives to concrete was investigated. For some time, researchers have been studying the physical properties of concrete to determine why the inclusion of rubber particles causes the concrete to degrade. Several methods have been developed to improve the bonding between rubber particles and cement hydration products (C-S-H) with the hope of creating a product with an improvement in mechanical strength. In this study, the crumb tyres were treated with waste organic sulfur compounds from a petroleum refining factory in order to modify their surface properties. Organic sulfur compounds with amphiphilic properties can enhance the hydrophilic properties of the rubber and increase the intermolecular interaction forces between rubber and C-S-H. In the present study, a colloid probe of C-S-H was prepared to measure these intermolecular interaction forces by utilizing an atomic force microscope. Experimental results showed that rubber particles treated with waste organic sulfur compounds became more hydrophilic. In addition, the intermolecular interaction forces increased with the adsorption of waste organic sulfur compounds on the surface of the rubber particles. The compressive, tensile and flexural strengths of concrete samples that included rubber particles treated with organic sulfur compound also increased significantly.

  9. Sulfur metabolism in phototrophic sulfur bacteria

    DEFF Research Database (Denmark)

    Frigaard, Niels-Ulrik; Dahl, Christiane

    2008-01-01

    Phototrophic sulfur bacteria are characterized by oxidizing various inorganic sulfur compounds for use as electron donors in carbon dioxide fixation during anoxygenic photosynthetic growth. These bacteria are divided into the purple sulfur bacteria (PSB) and the green sulfur bacteria (GSB......). They utilize various combinations of sulfide, elemental sulfur, and thiosulfate and sometimes also ferrous iron and hydrogen as electron donors. This review focuses on the dissimilatory and assimilatory metabolism of inorganic sulfur compounds in these bacteria and also briefly discusses these metabolisms...... in other types of anoxygenic phototrophic bacteria. The biochemistry and genetics of sulfur compound oxidation in PSB and GSB are described in detail. A variety of enzymes catalyzing sulfur oxidation reactions have been isolated from GSB and PSB (especially Allochromatium vinosum, a representative...

  10. Thermochemical Sulfate Reduction Simulation Experiments on the Formation and Distribution of Organic Sulfur Compounds in the Tuha Crude Oil

    Energy Technology Data Exchange (ETDEWEB)

    Yue, Changtao; Li, Shuyuan [China Univ. of Petroleum, Beijing (China); Song, He [Research Institute of Petroleum Engineering of CNPC, Tianjin (China)

    2014-07-15

    Thermochemical sulfate reduction (TSR) was conducted in autoclave on the system of crude oil and MgSO{sub 4} at different temperatures. Gas chromatography pulsed flame photometric detector (GC-PFPD) was used to detected the composition of organic sulfur compounds in oil phase products. The results of the analysis indicate that with increased temperature, the contents of organic sulfur compounds with high molecular weight and thermal stability, such as benzothiophenes and dibenzothiophenes, gradually became dominated. In order to gain greater insight into the formation and distribution of organic sulphur compounds from TSR, positive ion electrospray Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) was used in detecting the detailed elemental composition and distribution of them. The mass spectra showed that the mass range of sulfur compounds was 200-550 Da. Four sulfur class species, S{sub 1}, N{sub 1}S{sub 1}, O{sub 1}S{sub 1} and O{sub 2}S{sub 1}, were assigned in the positive-ion spectrum. Among the identified sulfur compounds, the S{sub 1} class species was dominant. The most abundant S{sub 1} class species increase associated with the DBE value and carbon number increasing which also indicates the evolution of organic sulfur compounds in TSR is from the labile series to the stable one. In pure blank pyrolysis experiments with crude oil cracking without TSR, different composition and distribution of organic sulfur compounds in oil phase products were seen from mass spectra in order to evaluate their pyrolysis behaviors without MgSO{sub 4}. FT-IR and XRD were used in analyzing the products of solid phases. Two distinct crystallographic phases MgO and MgSO{sub 4} are found to coexist in the products which demonstrated the transformation of inorganic sulfur compounds into organosulfur compounds exist in TSR.

  11. Determination of oxygen in uranium compounds using sulfur monochloride

    International Nuclear Information System (INIS)

    Baudin, G.; Besson, J.; Blum, P.L.; Tran-Van, Danh

    1964-01-01

    The authors have described in an other paper (Anal. Chim. Acta, in press) a method for oxygen determination in uranium compounds, in which the sample is attacked by sulfur monochloride. The present paper is concerned with the experimental aspects of the method: apparatus procedure. (authors) [fr

  12. Atmospheric degradation mechanism of organic sulfur compounds

    Energy Technology Data Exchange (ETDEWEB)

    Benter, T; Arsene, C

    2002-02-01

    In the present work a detailed product study has been performed on the OH radical initiated oxidation of dimethyl sulphide and dimethyl sulphoxide, under different conditions of temperature, partial pressure of oxygen and NO{sub x} concentration, in order to better define the degradation mechanism of the above compounds under conditions which prevail in the atmosphere. (orig.)

  13. Process for removal of sulfur compounds from fuel gases

    Science.gov (United States)

    Moore, Raymond H.; Stegen, Gary E.

    1978-01-01

    Fuel gases such as those produced in the gasification of coal are stripped of sulfur compounds and particulate matter by contact with molten metal salt. The fuel gas and salt are intimately mixed by passage through a venturi or other constriction in which the fuel gas entrains the molten salt as dispersed droplets to a gas-liquid separator. The separated molten salt is divided into a major and a minor flow portion with the minor flow portion passing on to a regenerator in which it is contacted with steam and carbon dioxide as strip gas to remove sulfur compounds. The strip gas is further processed to recover sulfur. The depleted, minor flow portion of salt is passed again into contact with the fuel gas for further sulfur removal from the gas. The sulfur depleted, fuel gas then flows through a solid absorbent for removal of salt droplets. The minor flow portion of the molten salt is then recombined with the major flow portion for feed to the venturi.

  14. Survey of electrochemical production of inorganic compounds. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1980-10-01

    The electrochemical generation of inorganic compounds, excluding chlorine/caustic, has been critically reviewed. About 60 x 10/sup 12/ Btu/y fossil fuel equivalent will be used in the year 2000 for the electrosynthesis of inorganic compounds. Significant energy savings in chlorate production can result from the development of suitable electrocatalysts for lowering the cathodic overpotential. Perchlorates, electrolytic hypochlorite, electrolytic manganese dioxide, fluorine and other miscellaneous compounds use relatively small amounts of electrical energy. Implementation of caustic scrubber technology for stack gas cleanup would result in appreciable amounts of sodium sulfate which could be electrolyzed to regenerate caustic. Hydrogen peroxide, now produced by the alkyl anthraquinone process, could be made electrolytically by a new process coupling anodic oxidation of sulfate with cathodic reduction of oxygen in alkaline solution. Ozone is currently manufactured using energy-inefficient silent discharge equipment. A novel energy-efficient approach which uses an oxygen-enhanced anodic reaction is examined.

  15. Gas chromatographic determination of impurities of inorganic compounds

    International Nuclear Information System (INIS)

    Drugov, Yu.S.

    1985-01-01

    Methods of concentration, separation, detection in gas chromatographic determination of impurities of inorganic compounds including low-boiling gases, reactive gases, organometallic compounds, free metals, anions, etc. are reviewed. Methods of reaction gas chromatography for determining reactive gases, water, anions, metal chelates are considered in detail as well as methods of reaction-sorption concentration and reaction gas extraction. The application of gas chromatograpny ior anaiysis of water and atmosphere contamination, for determination of impurities in highly pure solid substances and gases is described

  16. Occurrence and abatement of volatile sulfur compounds during biogas production.

    Science.gov (United States)

    Andersson, Fräs Annika T; Karlsson, Anna; Svensson, Bo H; Ejlertsson, Jörgen

    2004-07-01

    Volatile sulfur compounds (VSCs) in biogas originating from a biogas production plant and from a municipal sewage water treatment plant were identified. Samples were taken at various stages of the biogas-producing process, including upgrading the gas to vehicle-fuel quality. Solid-phase microextraction was used for preconcentration of the VSCs, which were subsequently analyzed using gas chromatography in combination with mass spectrometry. Other volatile organic compounds present also were identified. The most commonly occurring VSCs in the biogas were hydrogen sulfide, carbonyl sulfide, methanethiol, dimethyl sulfide, and dimethyl disulfide, and hydrogen sulfide was not always the most abundant sulfur (S) compound. Besides VSCs, oxygenated organic compounds were commonly present (e.g., ketones, alcohols, and esters). The effect of adding iron chloride to the biogas reactor on the occurrence of VSCs also was investigated. It was found that additions of 500-g/m3 substrate gave an optimal removal of VSCs. Also, the use of a prefermentation step could reduce the amount of VSCs formed in the biogas process. Moreover, in the carbon dioxide scrubber used for upgrading the gas, VSCs were removed efficiently, leaving traces (ppbv levels). The scrubber also removed other organic compounds.

  17. Some information needs for air quality modeling. [Environmental effects of sulfur compounds

    Energy Technology Data Exchange (ETDEWEB)

    Hill, F B

    1975-09-01

    The following topics were considered at the workshop: perturbation of the natural sulfur cycle by human activity; ecosystem responses to a given environmental dose of sulfur compounds; movement of sulfur compounds within the atmosphere; air quality models; contribution of biogenic sulfur compounds to atmospheric burden of sulfur; production of acid rain from sulfur dioxide; meteorological processes; and rates of oxidation of SO/sub 2/ via direct photo-oxidation, oxidation resulting from photo-induced free radical chemistry, and catalytic oxidation in cloud droplets and on dry particles. (HLW)

  18. Charge-density matching in organic-inorganic uranyl compounds

    International Nuclear Information System (INIS)

    Krivovichev, S.V.; Krivovichev, S.V.; Tananaev, I.G.; Myasoedov, B.F.

    2007-01-01

    Single crystals of [C 10 H 26 N 2 ][(UO 2 )(SeO 4 ) 2 (H 2 O)](H 2 SeO 4 ) 0.85 (H 2 O) 2 (1), [C 10 H 26 N 2 ][(UO 2 )(SeO 4 ) 2 ] (H 2 SeO 4 ) 0.50 (H 2 O) (2), and [C 8 H 20 N] 2 [(UO 2 )(SeO 4 ) 2 (H 2 O)] (H 2 O) (3) were prepared by evaporation from aqueous solution of uranyl nitrate, selenic acid and the respective amines. The structures of the compounds have been solved by direct methods and structural models have been obtained. The structures of the compounds 1, 2, and 3 contain U and Se atoms in pentagonal bipyramidal and tetrahedral coordinations, respectively. The UO 7 and SeO 4 polyhedra polymerize by sharing common O atoms to form chains (compound 1) or sheets (compounds 2 and 3). In the structure of 1, the layers consisting of hydrogen-bonded [UO 2 (SeO 4 ) 2 (H 2 O)] 2- chains are separated by mixed organic-inorganic layers comprising from [NH 3 (CH 2 ) 10 NH 3 ] 2+ molecules, H 2 O molecules, and disordered electroneutral (H 2 SeO 4 ) groups. The structure of 2 has a similar architecture but a purely inorganic layer is represented by a fully connected [UO 2 (SeO 4 ) 2 ] 2- sheet. The structure of 3 does not contain disordered (H 2 SeO 4 ) groups but is based upon alternating [UO 2 (SeO 4 ) 2 (H 2 O)] 2- sheets and 1.5-nm-thick organic blocks consisting of positively charged protonated octylamine molecules, [NH 3 (CH 2 ) 7 CH 3 ] + . The structures may be considered as composed of anionic inorganic sheets (2D blocks) and cationic organic blocks self-organized according to competing hydrophilic-hydrophobic interactions. Analysis of the structures allows us to conclude that the charge-density matching principle is observed in uranyl compounds. In order to satisfy some basic peculiarities of uranyl (in general, actinyl) chemistry, it requires specific additional mechanisms: (a) in long-chain-amine-templated compounds, protonated amine molecules inter-digitate; (b) in long-chain-diamine-templated compounds, incorporation of acid-water interlayers into

  19. HPLC inorganic arsenic speciation analysis of samples containing high sulfuric acid and iron levels

    NARCIS (Netherlands)

    Gonzalez-Contreras, P.A.; Gerrits, I.P.A.M.; Weijma, J.; Buisman, C.J.N.

    2011-01-01

    To monitor the oxidation of arsenite to arsenate in oxidizing and bioleaching reactors, speciation analysis of the inorganic arsenic compounds is required. Existing arsenic speciation analysis techniques are based on the use of liquid chromatography columns coupled to detector equipment such as

  20. Sulfur-binding in recent environments: II. Speciation of sulfur and iron and implications for the occurrence of organo-sulfur compounds

    Science.gov (United States)

    Hartgers, Walter A.; Lòpez, Jordi F.; Sinninghe Damsté, Jaap S.; Reiss, Christine; Maxwell, James R.; Grimalt, Joan O.

    1997-11-01

    Speciation of iron and sulfur species was determined for two recent sediments (La Trinitat and Lake Cisó) which were deposited in environments with a high biological productivity and sulfate-reducing activity. In sediments from calcite ponds of La Trinitat an excess of reactive iron species (iron monosulfides, iron hydroxides) results in a depletion of reactive sulfur which is accompanied by a virtual absence of organo-sulfur compounds, both in low (LMW) and high molecular-weight (HMW) fractions. Small amounts of phytanyl and highly branched isoprenoid (HBI) thiophenes in the extract demonstrate that these molecules exhibit a higher reactivity towards reduced sulfur species as compared to detrital iron. Euxinic sediments from Lake Cisó are characterised by an excess of reduced sulfur species which can rapidly trap reactive iron. High concentrations of H 2S results in the formation of organo-sulfur compounds which were encountered in both LMW and HMW fractions. The major part of the organic sulfur is bound to the carbohydrate portion of woody tissues, whose presence was revealed by a specific alkylthiophene distribution in the flash pyrolysate and by Li/EtNH 2 desulfurisation of the kerogen which resulted in the solubilisation of the sulfur-enriched hemicellulose fraction. Relatively high amounts of sulfurised C 25 HBI compounds in the sediment extract of Lake Cisó reflect the incorporation of sulfur into algal derived organic matter upon early diagenesis. The combined approach of the speciation of iron and sulfur species and the molecular analysis of sedimentary fractions demonstrates that abiotic sulfur binding to organic matter occurs at the earliest stages of diagenesis under specific depositional conditions (anoxic, stratified water column) in which an excess of reduced sulfur species relative to the amount of reactive iron is a controlling factor.

  1. Oxidation of refractory sulfur compounds over Ti-containing mesoporous molecular sieves prepared by using a fluorosilicon compound.

    Science.gov (United States)

    Jeong, Kwang-Eun; Cho, Chin-Soo; Chae, Ho-Jeong; Kim, Chul-Ung; Jeong, Soon-Yong

    2010-05-01

    Titanium containing mesoporous molecular sieve (Ti-MMS) catalysts were studied for the oxidative desulfurization of refractory sulfur compounds. Ti-MMS catalysts were synthesized from fluorosilicon compounds and Ti with the hydrolysis reaction of H2SiF6 in an ammonia-surfactant mixed solution. The solid products were characterized by XRD, XRF, nitrogen adsorption, and diffuse reflectance UV-vis spectroscopy. Effects of Ti loading and oxidant/sulfur mole ratio, and sulfur species on ODS activity were investigated.

  2. Charge-density matching in organic-inorganic uranyl compounds

    Energy Technology Data Exchange (ETDEWEB)

    Krivovichev, S.V. [Saint Petersburg State Univ., Dept. of Crystallography, Faculty of Geology (Russian Federation); Krivovichev, S.V.; Tananaev, I.G.; Myasoedov, B.F. [Russian Academy of Sciences, A.N. Frumkin Institute of Physical Chemistry and Electrochemistry, Moscow (Russian Federation)

    2007-10-15

    Single crystals of [C{sub 10}H{sub 26}N{sub 2}][(UO{sub 2})(SeO{sub 4}){sub 2}(H{sub 2}O)](H{sub 2}SeO{sub 4}){sub 0.85}(H{sub 2}O){sub 2} (1), [C{sub 10}H{sub 26}N{sub 2}][(UO{sub 2})(SeO{sub 4}){sub 2}] (H{sub 2}SeO{sub 4}){sub 0.50}(H{sub 2}O) (2), and [C{sub 8}H{sub 20}N]{sub 2}[(UO{sub 2})(SeO{sub 4}){sub 2}(H{sub 2}O)] (H{sub 2}O) (3) were prepared by evaporation from aqueous solution of uranyl nitrate, selenic acid and the respective amines. The structures of the compounds have been solved by direct methods and structural models have been obtained. The structures of the compounds 1, 2, and 3 contain U and Se atoms in pentagonal bipyramidal and tetrahedral coordinations, respectively. The UO{sub 7} and SeO{sub 4} polyhedra polymerize by sharing common O atoms to form chains (compound 1) or sheets (compounds 2 and 3). In the structure of 1, the layers consisting of hydrogen-bonded [UO{sub 2}(SeO{sub 4}){sub 2}(H{sub 2}O)]{sup 2-} chains are separated by mixed organic-inorganic layers comprising from [NH{sub 3}(CH{sub 2}){sub 10}NH{sub 3}]{sup 2+} molecules, H{sub 2}O molecules, and disordered electroneutral (H{sub 2}SeO{sub 4}) groups. The structure of 2 has a similar architecture but a purely inorganic layer is represented by a fully connected [UO{sub 2}(SeO{sub 4}){sub 2}]{sup 2-} sheet. The structure of 3 does not contain disordered (H{sub 2}SeO{sub 4}) groups but is based upon alternating [UO{sub 2}(SeO{sub 4}){sub 2}(H{sub 2}O)]{sup 2-} sheets and 1.5-nm-thick organic blocks consisting of positively charged protonated octylamine molecules, [NH{sub 3}(CH{sub 2}){sub 7}CH{sub 3}]{sup +}. The structures may be considered as composed of anionic inorganic sheets (2D blocks) and cationic organic blocks self-organized according to competing hydrophilic-hydrophobic interactions. Analysis of the structures allows us to conclude that the charge-density matching principle is observed in uranyl compounds. In order to satisfy some basic peculiarities of uranyl (in

  3. MANOVA statistical analysis of inorganic compounds in groundwater Indonesia

    Energy Technology Data Exchange (ETDEWEB)

    Tanty, Heruna, E-mail: herunatanty@yahoo.com [Department of Mathematics, Bina Nusantara University, Jl. K.H. Syahdan No. 9 Palmerah, Jakarta Barat (Indonesia); Bekti, Rokhana Dwi, E-mail: groo-jgroo@yahoo.com [Department of Statistics, Bina Nusantara University, Jl. K.H. Syahdan No. 9 Palmerah, Jakarta Barat (Indonesia); Herlina, Tati, E-mail: tatat-04her@yahoo.com, E-mail: nurlelasari@unpad.ac.id; Nurlelasari, E-mail: tatat-04her@yahoo.com, E-mail: nurlelasari@unpad.ac.id [Department of Chemistry, University of Padjajaran, Jl. Raya Jatinangor-Sumedang km 21, Jatinangor 45363, Jawa Barat (Indonesia)

    2014-10-24

    The present study was carried out to determine levels of inorganic compounds contained in the ground water and Reverse Osmosis (RO) water filtration result. The data in groundwater samples was collected from Bekasi, Tangerang and Jakarta in Indonesia. A total of 30 samples were collected and analyzed for the determine Cadmium (Cd), Chromium (Cr), Manganese (Mn), Cyanide (CN) and Lead (Pb). The results of the study revealed that in groundwater, the average of Cd 0.0058 mg / l, Mn 1.5233 mg / l, Cr 0.0127 mg/l, Pb 0.0060 mg / l, and CN 0.0040 mg / l. The level of RO result were: Cd 0.0027 mg / l, Mn 0.1767 mg / l, Cr 0.0024 mg / l, Pb 0.0021 mg / l, and CN 0.0023 mg / l . This means that Cd and Mn in ground water were higher than the values recommended by PAK-EPA and WHO or the standard of Indonesian Ministry of Health. But after filtration Reverse Osmosis (RO) Mn and Cd levels decreased to levels below the standardized value. By comparing of mean in MANOVA and nonparametric MANOVA in α=5%, there are differences in average levels of inorganic substances Mn, Cr, Cd, Pb, and CN between before and after RO filtration.

  4. Physiology of alkaliphilic sulfur-oxidizing bacteria from soda lakes

    NARCIS (Netherlands)

    Banciu, H.L.

    2004-01-01

    The inorganic sulfur oxidation by obligate haloalkaliphilic chemolithoautotrophs was only recently discovered and investigated. These autotrophic sulfur oxidizing bacteria (SOB), capable of oxidation of inorganic sulfur compounds at moderate to high salt concentration and at high pH, can be divided

  5. Tandem sulfur chemiluminescence and flame ionization detection with planar microfluidic devices for the characterization of sulfur compounds in hydrocarbon matrices.

    Science.gov (United States)

    Luong, J; Gras, R; Shellie, R A; Cortes, H J

    2013-07-05

    The detection of sulfur compounds in different hydrocarbon matrices, from light hydrocarbon feedstocks to medium synthetic crude oil feeds provides meaningful information for optimization of refining processes as well as demonstration of compliance with petroleum product specifications. With the incorporation of planar microfluidic devices in a novel chromatographic configuration, sulfur compounds from hydrogen sulfide to alkyl dibenzothiophenes and heavier distributions of sulfur compounds over a wide range of matrices spanning across a boiling point range of more than 650°C can be characterized, using one single analytical configuration in less than 25min. In tandem with a sulfur chemiluminescence detector for sulfur analysis is a flame ionization detector. The flame ionization detector can be used to establish the boiling point range of the sulfur compounds in various hydrocarbon fractions for elemental specific simulated distillation analysis as well as profiling the hydrocarbon matrices for process optimization. Repeatability of less than 3% RSD (n=20) over a range of 0.5-1000 parts per million (v/v) was obtained with a limit of detection of 50 parts per billion and a linear range of 0.5-1000 parts per million with a correlation co-efficient of 0.998. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Corrosion evaluation of materials in sulfur compound environments

    International Nuclear Information System (INIS)

    Maoying Teng; Iuanjou Yang

    1993-01-01

    The para-toluene sulfonic acid (PTSA) serves as a catalyst in producing diethylene glycol dibenzoate (DEGDB) and decomposes with increasing time at elevated temperature. Due to the presence of bisulfite ion, it is important to evaluate the corrosion properties of materials in this metastable environments. A potentiodynamic method was used to screen materials' properties in a PTSA solution. A surface analysis technique was also performed to investigate the oxide films. The critical current density and passive current density were substantially reduced when Fe alloyed with Cr and/or Ni. With the addition of Mo in Fe-Ni-Cr alloys, the critical current density was lowered further to show the beneficial effect of alloyed Mo. A plot of the corrosion rate of materials in DEGDB as a function of Ni/Cr ratio shows the linearity with increasing Ni/Cr ratio, disregard the type of materials. The corrosion rate of pure chromium can be estimated as ∼ 2.0 mpy by extrapolation of the linearity to Ni/Cr = 0. This is also the minimum corrosion rate that even Fe-Ni-Cr alloys were alloyed with Mo. Surface analysis results showed that the dissolution of Fe and/or Ni leads to a higher surface chromium content and results in the formation of chromium oxide on metal surface. This chromium oxide then prevents metal from corrosion. It is concluded that the higher the nickel content the higher the corrosion rate of materials. The composition potential-pH diagrams for Fe-S-H 2 O and Ni-S-H 2 O show that the stability fields of FeS and NiS cover a wide range of pH. The effect of sulfur or sulfide ions in promoting dissolution of Fe and/or Ni are highly possible. The activating influence of sulfur compounds on Ni is stronger than that of Fe, although the highly electronic conductivity of iron sulfides can catalyze the cathodic reaction. Undoubtedly, sulfur compound strongly depassivates high Ni contents materials

  7. INFLUENCE OF INORGANIC COMPOUNDS ON THE PROCESS OF PHOTOCATALYSIS OF BIOLOGICALLY ACTIVE COMPOUNDS

    Directory of Open Access Journals (Sweden)

    Edyta Kudlek

    2017-07-01

    Full Text Available Constant increase in concentration of organic micropollutants in the water environment influences the development of methods for their effective elimination from various matrices released into aquatic ecosystems. One of widely described in literature processes for the decomposition of hardly-biodegradable pollutants is the process of heterogeneous photocatalysis. The paper presents the influence of inorganic substances on the decomposition of polycyclic aromatic hydrocarbons (anthracene and benzo[a]pyrene, industrial admixtures - octylphenol and pharmaceutical compounds - diclofenac in the photocatalysis process conducted in the presence of TiO2. It has been shown that the presence of Cl- ions did not affect the photochemical reaction of the micropollutant decomposition. Whereas, the presence of CO3(2-, SO4(2- and HPO4(2- ions inhibited the decolonization of octylphenol and diclofenac, while the degradation efficiency of anthracene and benzo[a]pyrene was reduced only by the presence of CO3(2- and HCO3- anions. The photooxidation of micropollutants in solutions containing Al(3+ oraz Fe(3+ cations proceeded with a much lower efficiency than that for solution without inorganic compounds. The analysis of the kinetics of the photocatalytic decomposition of selected micropollutants show a decrease in the reaction rate constant and an increase in their half-life due to the blocking of theactive semiconductor centers by inorganic compounds. In addition,the toxicological analysis inducated the generation of micropollutant oxidation by-products, which aggravate the quality of treated aqueous solutions.

  8. Quadruple sulfur isotope constraints on the origin and cycling of volatile organic sulfur compounds in a stratified sulfidic lake

    Science.gov (United States)

    Oduro, Harry; Kamyshny, Alexey; Zerkle, Aubrey L.; Li, Yue; Farquhar, James

    2013-11-01

    We have quantified the major forms of volatile organic sulfur compounds (VOSCs) distributed in the water column of stratified freshwater Fayetteville Green Lake (FGL), to evaluate the biogeochemical pathways involved in their production. The lake's anoxic deep waters contain high concentrations of sulfate (12-16 mmol L-1) and sulfide (0.12 μmol L-1 to 1.5 mmol L-1) with relatively low VOSC concentrations, ranging from 0.1 nmol L-1 to 2.8 μmol L-1. Sulfur isotope measurements of combined volatile organic sulfur compounds demonstrate that VOSC species are formed primarily from reduced sulfur (H2S/HS-) and zero-valent sulfur (ZVS), with little input from sulfate. Thedata support a role of a combination of biological and abiotic processes in formation of carbon-sulfur bonds between reactive sulfur species and methyl groups of lignin components. These processes are responsible for very fast turnover of VOSC species, maintaining their low levels in FGL. No dimethylsulfoniopropionate (DMSP) was detected by Electrospray Ionization Mass Spectrometry (ESI-MS) in the lake water column or in planktonic extracts. These observations indicate a pathway distinct from oceanic and coastal marine environments, where dimethylsulfide (DMS) and other VOSC species are principally produced via the breakdown of DMSP by plankton species.

  9. Metabolomic profiling of the purple sulfur bacterium Allochromatium vinosum during growth on different reduced sulfur compounds and malate

    OpenAIRE

    Weissgerber, Thomas; Watanabe, Mutsumi; Hoefgen, Rainer; Dahl, Christiane

    2014-01-01

    Environmental fluctuations require rapid adjustment of the physiology of bacteria. Anoxygenic phototrophic purple sulfur bacteria, like Allochromatium vinosum, thrive in environments that are characterized by steep gradients of important nutrients for these organisms, i.e., reduced sulfur compounds, light, oxygen and carbon sources. Changing conditions necessitate changes on every level of the underlying cellular and molecular network. Thus far, two global analyses of A. vinosum responses to ...

  10. Control of Copper Resistance and Inorganic Sulfur Metabolism by Paralogous Regulators in Staphylococcus aureus*

    Science.gov (United States)

    Grossoehme, Nicholas; Kehl-Fie, Thomas E.; Ma, Zhen; Adams, Keith W.; Cowart, Darin M.; Scott, Robert A.; Skaar, Eric P.; Giedroc, David P.

    2011-01-01

    All strains of Staphylococcus aureus encode a putative copper-sensitive operon repressor (CsoR) and one other CsoR-like protein of unknown function. We show here that NWMN_1991 encodes a bona fide Cu(I)-inducible CsoR of a genetically unlinked copA-copZ copper resistance operon in S. aureus strain Newman. In contrast, an unannotated open reading frame found between NWMN_0027 and NWMN_0026 (denoted NWMN_0026.5) encodes a CsoR-like regulator that represses expression of adjacent genes by binding specifically to a pair of canonical operator sites positioned in the NWMN_0027–0026.5 intergenic region. Inspection of these regulated genes suggests a role in assimilation of inorganic sulfur from thiosulfate and vectorial sulfur transfer, and we designate NWMN_0026.5 as CstR (CsoR-like sulfur transferase repressor). Expression analysis demonstrates that CsoR and CstR control their respective regulons in response to distinct stimuli with no overlap in vivo. Unlike CsoR, CstR does not form a stable complex with Cu(I); operator binding is instead inhibited by oxidation of the intersubunit cysteine pair to a mixture of disulfide and trisulfide linkages by a likely metabolite of thiosulfate assimilation, sulfite. CsoR is unreactive toward sulfite under the same conditions. We conclude that CsoR and CstR are paralogs in S. aureus that function in the same cytoplasm to control distinct physiological processes. PMID:21339296

  11. Control of copper resistance and inorganic sulfur metabolism by paralogous regulators in Staphylococcus aureus.

    Science.gov (United States)

    Grossoehme, Nicholas; Kehl-Fie, Thomas E; Ma, Zhen; Adams, Keith W; Cowart, Darin M; Scott, Robert A; Skaar, Eric P; Giedroc, David P

    2011-04-15

    All strains of Staphylococcus aureus encode a putative copper-sensitive operon repressor (CsoR) and one other CsoR-like protein of unknown function. We show here that NWMN_1991 encodes a bona fide Cu(I)-inducible CsoR of a genetically unlinked copA-copZ copper resistance operon in S. aureus strain Newman. In contrast, an unannotated open reading frame found between NWMN_0027 and NWMN_0026 (denoted NWMN_0026.5) encodes a CsoR-like regulator that represses expression of adjacent genes by binding specifically to a pair of canonical operator sites positioned in the NWMN_0027-0026.5 intergenic region. Inspection of these regulated genes suggests a role in assimilation of inorganic sulfur from thiosulfate and vectorial sulfur transfer, and we designate NWMN_0026.5 as CstR (CsoR-like sulfur transferase repressor). Expression analysis demonstrates that CsoR and CstR control their respective regulons in response to distinct stimuli with no overlap in vivo. Unlike CsoR, CstR does not form a stable complex with Cu(I); operator binding is instead inhibited by oxidation of the intersubunit cysteine pair to a mixture of disulfide and trisulfide linkages by a likely metabolite of thiosulfate assimilation, sulfite. CsoR is unreactive toward sulfite under the same conditions. We conclude that CsoR and CstR are paralogs in S. aureus that function in the same cytoplasm to control distinct physiological processes.

  12. Garlic Sulfur Compounds Suppress Cancerogenesis and Oxidative Stress: a Review

    Directory of Open Access Journals (Sweden)

    Dvořáková M.

    2015-06-01

    Full Text Available Garlic has long been considered a food with many health benefits. Several studies have confirmed that sulfur compounds are responsible for the positive effects of garlic on organisms. Garlic acts as an antioxidant by increasing antioxidant enzyme activity, reducing reactive oxygen species generation, and protecting proteins and lipids from oxidation. Garlic suppresses carcinogenesis through several mechanisms: (1 it reduces oxidative stress, and therefore, prevents damage to DNA; (2 it induces apoptosis or cell cycle arrest in cancer cells; and (3 it modifies gene expression through histon acetylation. The positive effects of garlic could be mediated by several mechanisms. It influences signalling pathways of gasotransmitters such as hydrogen sulfide. Garlic enhances hydrogen sulfide production both through its direct release and through an increase in activity of enzymes which produce hydrogen sulfide. Hydrogen sulfide acts as a signalling molecule in various tissues and participates in the regulation of many physiological processes. We can presume that garlic, which is able to release hydrogen sulfide, exhibits effects similar to those of this gasotransmitter.

  13. Determination of sulfur compounds in hydrotreated transformer base oil by potentiometric titration.

    Science.gov (United States)

    Chao, Qiu; Sheng, Han; Cheng, Xingguo; Ren, Tianhui

    2005-06-01

    A method was developed to analyze the distribution of sulfur compounds in model sulfur compounds by potentiometric titration, and applied to analyze hydrotreated transformer base oil. Model thioethers were oxidized to corresponding sulfoxides by tetrabutylammonium periodate and sodium metaperiodate, respectively, and the sulfoxides were titrated by perchloric acid titrant in acetic anhydride. The contents of aliphatic thioethers and total thioethers were then determined from that of sulfoxides in solution. The method was applied to determine the organic sulfur compounds in hydrotreated transformer base oil.

  14. Multi-Phase Equilibrium and Solubilities of Aromatic Compounds and Inorganic Compounds in Sub- and Supercritical Water: A Review.

    Science.gov (United States)

    Liu, Qinli; Ding, Xin; Du, Bowen; Fang, Tao

    2017-11-02

    Supercritical water oxidation (SCWO), as a novel and efficient technology, has been applied to wastewater treatment processes. The use of phase equilibrium data to optimize process parameters can offer a theoretical guidance for designing SCWO processes and reducing the equipment and operating costs. In this work, high-pressure phase equilibrium data for aromatic compounds+water systems and inorganic compounds+water systems are given. Moreover, thermodynamic models, equations of state (EOS) and empirical and semi-empirical approaches are summarized and evaluated. This paper also lists the existing problems of multi-phase equilibria and solubility studies on aromatic compounds and inorganic compounds in sub- and supercritical water.

  15. [Distribution and sources of oxygen and sulfur heterocyclic aromatic compounds in surface soil of Beijing, China].

    Science.gov (United States)

    He, Guang-Xiu; Zhang, Zhi-Huan; Peng, Xu-Yang; Zhu, Lei; Lu, Ling

    2011-11-01

    62 surface soil samples were collected from different environmental function zones in Beijing. Sulfur and oxygen heterocyclic aromatic compounds were detected by GC/MS. The objectives of this study were to identify the composition and distribution of these compounds, and discuss their sources. The results showed that the oxygen and sulfur heterocyclic aromatic compounds in the surface soils mainly contained dibenzofuran, methyl- and C2-dibenzofuran series, dibenzothiophene, methyl-, C2- and C3-dibenzothiophene series and benzonaphthothiophene series. The composition and distribution of the oxygen and sulfur heterocyclic aromatic compounds in the surface soil samples varied in the different environmental function zones, of which some factories and the urban area received oxygen and sulfur heterocyclic aromatic compounds most seriously. In Beijing, the degree of contamination by oxygen and sulfur heterocyclic aromatic compounds in the north surface soil was higher than that in the south. There were preferable linear correlations between the concentration of dibenzofuran series and fluorene series, as well as the concentration of dibenzothiophene series and dibenzofuran series. The oxygen and sulfur heterocyclic aromatic compounds in the surface soil were mainly derived from combustion products of oil and coal and direct input of mineral oil, etc. There were some variations in pollution sources of different environmental function zones.

  16. Conversion of sulfur compounds and microbial community in anaerobic treatment of fish and pork waste.

    Science.gov (United States)

    He, Ruo; Yao, Xing-Zhi; Chen, Min; Ma, Ruo-Chan; Li, Hua-Jun; Wang, Chen; Ding, Shen-Hua

    2018-04-07

    Volatile sulfur compounds (VSCs) are not only the main source of malodor in anaerobic treatment of organic waste, but also pose a threat to human health. In this study, VSCs production and microbial community was investigated during the anaerobic degradation of fish and pork waste. The results showed that after the operation of 245 days, 94.5% and 76.2% of sulfur compounds in the fish and pork waste was converted into VSCs. Among the detected VSCs including H 2 S, carbon disulfide, methanethiol, ethanethiol, dimethyl sulfide, dimethyl disulfide and dimethyl trisulfide, methanethiol was the major component with the maximum concentration of 4.54% and 3.28% in the fish and pork waste, respectively. The conversion of sulfur compounds including total sulfur, SO 4 2- -S, S 2- , methionine and cysteine followed the first-order kinetics. Miseq sequencing analysis showed that Acinetobacter, Clostridium, Proteus, Thiobacillus, Hyphomicrobium and Pseudomonas were the main known sulfur-metabolizing microorganisms in the fish and pork waste. The C/N value had most significant influence on the microbial community in the fish and pork waste. A main conversion of sulfur compounds with CH 3 SH as the key intermediate was firstly hypothesized during the anaerobic degradation of fish and pork waste. These findings are helpful to understand the conversion of sulfur compounds and to develop techniques to control ordor pollution in the anaerobic treatment of organic waste. Copyright © 2018. Published by Elsevier Ltd.

  17. Measurements of sulfur compounds in CO2 by diode laser atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Franzke, J.; Stancu, D.G.; Niemax, K.

    2003-01-01

    Two simple methods for the analysis of the total concentration of sulfur in CO 2 by diode laser atomic absorption spectrometry of excited, metastable sulfur atoms in a direct current discharge are presented. In the first method, the CO 2 sample gas is mixed with the plasma gas (Ar or He) while the second is based on reproducible measurements of the sulfur released from the walls in a helium discharge after being deposited as a result of operating the discharge in pure CO 2 sample gas. The detection limits obtained satisfy the requirements for the control of sulfur compounds in CO 2 used in the food and beverage industry

  18. Understanding chemistry behind secondary aerosol production from nitrogen and sulfur compounds from agriculture

    Science.gov (United States)

    Agricultural emissions impact particulate mass concentrations through both primary and secondary processes. Evidence from laboratory and field work suggest that not only does ammonia produce secondary particulate matter, but nitrogen and sulfur containing volatile organic compounds also contribute. ...

  19. Modelling of the Kinetics of Sulfure Compounds in Desulfurisation Processes Based on Industry Data of Plant

    Directory of Open Access Journals (Sweden)

    Krivtcova Nadezhda

    2016-01-01

    Full Text Available Modelling of sulfur compounds kinetics was performed, including kinetics of benzothiophene and dibenzothiophene homologues. Modelling is based on experimental data obtained from monitoring of industrial hydrotreating set. Obtained results include kinetic parameters of reactions.

  20. Modelling of the Kinetics of Sulfure Compounds in Desulfurisation Processes Based on Industry Data of Plant

    OpenAIRE

    Krivtsova, Nadezhda Igorevna; Tataurshikov, A.; Kotkova, Elena

    2016-01-01

    Modelling of sulfur compounds kinetics was performed, including kinetics of benzothiophene and dibenzothiophene homologues. Modelling is based on experimental data obtained from monitoring of industrial hydrotreating set. Obtained results include kinetic parameters of reactions.

  1. The Soft X-Ray Spectra of Sulfur Compounds.

    Science.gov (United States)

    Zhou, Ling

    1995-01-01

    The sulfur compounds including CdS, ZnS, rm MoS_2, WS_2, NiS, FeS, GaS, SnS, MgS and Alloy rm ZnS_{x }Se_{1-x} were investigated by using photon/e-beam excited soft x-ray spectroscopy through SXA, SXE, SXF and inelastic Resonant Raman scattering and resonant elastic scattering processes. For valence bands, the PDOS of S L_{2,3}, Zn M_{2,3}, Se M _{4,5}, bands locations, band gaps Eg, core level spin splitting, the lifetime broadening of valence band t_{1/2}, branching ratio of rm L_2/L_3 and shallow d level and exciton state were measured in some of these materials respectively. The excitation mechanism or threshold effects were studied for CdS, ZnS, MoS_2, WS_2, FeS, NiS, and alloy. In photon excited S L_ {2,3}^ectra, local core levels with spin splitting were found to charge threshold effects. The threshold effects are also found to be influenced by resonant elastic and inelastic scattering process. A simple model and the second order perturbation theory are used to explain the observed inelastic Raman scattering of Zn M _{2,3} spectra near d threshold. The d participation in the chemical bonding and interactions was studied. Atomiclike d bands were found in FeS and NiS from strong d-d and d-p couplings. Two groups of d bands were observed in Transitional Metal Sulfides (TMS) and the no-bonding group with a few d bands was found to across whole valence bands in TMS. The direct connection between valence bands and conduction bands is built and some conduction bands were studied. A study of alloy was included briefly. These experiments provide a rich information about TMS, and prove that Soft X-ray Spectroscopy is a powerful, precise and reliable tool in the study of fine electronic band structure in solids.

  2. Possible interferences of mercury sulfur compounds with ethylated and methylated mercury species using HPLC-ICP-MS

    International Nuclear Information System (INIS)

    Wilken, R.D.; Nitschke, F.; Falter, R.

    2003-01-01

    The HPLC-ICP-MS coupling technique is able to separate and detect methyl, ethyl and inorganic mercury isotopes specifically. An identification of ethyl mercury(+) is not possible when the widely used sodium tetraethylborate derivatisation method in combination with GC-AFS/AAS or ICP-MS techniques is performed because it contains ethyl groups. An unidentified compound with the same retention time as ethyl mercury was found in the HPLC chromatograms of industrial sewage samples and humic-rich soils of microcosm experiments after applying water vapour distillation. We also observed such unidentified peaks in samples of heavily contaminated sites in Eastern Germany, separated by HPLC fractionation only. In the experiments described, different mercury sulfur adducts were synthesised and tested for their retention times in the HPLC-ICP-MS system. It was found that the compound CH 3 -S-Hg + showed the same retention time as the ethyl mercury standard. It is therefore possible that ethyl mercury detected in chromatography by comparison of the retention time could also be due to an adduct of a sulfur compound and a mercury species. CH 3 -S-Hg + should be tested in other chromatographic mercury speciation methods for this effect. This work can also be regarded as a contribution to the discussion of artificially occurring methyl mercury in sediments during sample preparation. (orig.)

  3. Sulfur Fixation by Chemically Modified Red Mud Samples Containing Inorganic Additives: A Parametric Study

    Directory of Open Access Journals (Sweden)

    Yang Liu

    2016-01-01

    Full Text Available Sulfur retention ability of Bayer red mud from alumina plant was investigated. Bayer red mud modified by fusel salt and waste mother liquor of sodium ferrocyanide as the main sulfur fixation agent and the calcium based natural mineral materials as servicing additives; the experimental results showed the following: (1 Through 10 wt% waste mother liquor of sodium ferrocyanide modifying Bayer red mud, sulfur fixation rate can increase by 13 wt%. (2 Magnesium oxide can obviously improve the sulfur fixation performance of Bayer red mud and up to a maximum sulfur fixation rate of 47 wt% at adding 1 wt% magnesium oxide. (3 Dolomite enhanced the sulfur fixation performances with the sulfur fixation rate of 68 wt% in optimized condition. (4 Vermiculite dust reduced sulfur dioxide during the fixed-sulfur process of modified Bayer red mud, and the desulphurization ration could reach up to a maximum 76 wt% at 950°C. (5 An advanced three-component sulfur fixation agent was investigated, in which the optimized mass ratio of modified Bayer red mud, dolomite, and vermiculite dust was 70 : 28 : 2 in order, and its sulfur fixation efficiency has reached to a maximum 87 wt% under its 20 wt% dosage in the coal.

  4. Quantitative on-line analysis of sulfur compounds in complex hydrocarbon matrices.

    Science.gov (United States)

    Djokic, Marko R; Ristic, Nenad D; Olahova, Natalia; Marin, Guy B; Van Geem, Kevin M

    2017-08-04

    An improved method for on-line measurement of sulfur containing compounds in complex matrices is presented. The on-line system consists of a specifically designed sampling system connected to a comprehensive two-dimensional gas chromatograph (GC×GC) equipped with two capillary columns (Rtx ® -1 PONA×SGE BPX50), a flame ionization detector (FID) and a sulfur chemiluminescence detector (SCD). The result is an unprecedented sensitivity down to ppm level (1 ppm-w) for various sulfur containing compounds in very complex hydrocarbon matrices. In addition to the GC×GC-SCD, the low molecular weight sulfur containing compounds such as hydrogen sulfide (H 2 S) and carbonyl sulfide (COS) can be analyzed using a thermal conductivity detector of a so-called refinery gas analyzer (RGA). The methodology was extensively tested on a continuous flow pilot plant for steam cracking, in which quantification of sulfur containing compounds in the reactor effluent was carried out using 3-chlorothiophene as internal standard. The GC×GC-FID/-SCD settings were optimized for ppm analysis of sulfur compounds in olefin-rich (ethylene- and propylene-rich) hydrocarbon matrices produced by steam cracking of petroleum feedstocks. Besides that is primarily used for analysis of the hydrocarbon matrix, FID of the GC×GC-FID/-SCD set-up serves to double check the amount of added sulfur internal standard which is crucial for a proper quantification of sulfur compounds. When vacuum gas oil containing 780 ppm-w of elemental sulfur in the form of benzothiophenes and dibenzothiophenes is subjected to steam cracking, the sulfur balance was closed, with 75% of the sulfur contained in the feed is converted to hydrogen sulfide, 13% to alkyl homologues of thiophene while the remaining 12% is present in the form of alkyl homologues of benzothiophenes. The methodology can be applied for many other conversion processes which use sulfur containing feeds such as hydrocracking, catalytic cracking, kerogen

  5. Composition of atmospheric precipitation. II. Sulfur, chloride, iodine compounds. Bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Eriksson, E

    1952-01-01

    Atmospheric precipitation invariably contains insoluble substances of different origin. A large scale study was conducted to determine the content of sulfur, chloride, and iodine in rainwater from various places around the world. The origin of these elements in rainwater is discussed. Several meteorological factors influence the Cl-content of rainwater. They include: rainfall, wind direction and wind strength, altitude, and seasonal variation.

  6. Online air analysis of reduced sulfur compounds at a swine facility

    Science.gov (United States)

    Reduced sulfur compounds are emitted from waste management handling and can be important in odor production and atmospheric chemistry. Data on the emissions of these compounds have been obtained using off-line sampling and analysis methods, but on-line methods providing information on temporal chang...

  7. Binary systems solubilities of inorganic and organic compounds, v.1 pt.2

    CERN Document Server

    Stephen, H

    2013-01-01

    Solubilities of Inorganic and Organic Compounds, Volume 1: Binary Systems, Part 1 is part of an approximately 5,500-page manual containing a selection from the International Chemical Literature on the Solubilities of Elements, Inorganic Compounds, Metallo-organic and Organic Compounds in Binary, Ternary and Multi-component Systems. A careful survey of the literature in all languages by a panel of scientists specially appointed for the task by the U.S.S.R. Academy of Sciences, Moscow, has made the compilation of this work possible. The complete English edition in five separately bound volumes w

  8. Sulfur compounds and species in Russian residues by XPS and PY-GC-PFPO

    Energy Technology Data Exchange (ETDEWEB)

    Quan, S.; Suoqi, Z.; Chunming, X. [University of Petroleum, State Key Laboraory of Heavy Oil Processing, Beijing (China); Kotlyar, L.; Kung, J. [National Research Council of Canada, Institute for Chemical processand Environmental Technology, Ottawa, ON (Canada); Chung, K. H. [Syncrude Canada Limited, Edmonton, AB (Canada)

    2004-07-01

    Distribution and structure of sulfur components of Russian crude oil were investigated by separating vacuum residues from the oil into 17 narrow cuts and one end-cut using the supercritical fluid extraction and fractionation technique (SFEF). The cuts were analyzed by gas chromatography, with conditions optimized from 600 degrees C to 1,000 degrees C, and between two and twenty seconds. In general, the total amount of of the sulfur compounds in pyrolizates was found to be proportional to the sulfur content in the vacuum residues. Thiophenes, benzothiophenes and dibenzothiophene content varied from vacuum residue to vacuum residue. Benzothiophens were identified as the dominant sulfur compounds in the pyrolizate of Russian crude oil.

  9. Structure of inorganic phosphorus-nitrogen tetrahedral compounds

    International Nuclear Information System (INIS)

    Vitola, A.; Ronis, J.; Avotins, V.; Millers, T.

    1997-01-01

    The structure analysis of phosphorus-nitrogen compounds has shown the possibility of the P(O,N) 4 tetrahedra to form various kinds of structures. The wide spectrum of the properties determined by the diversity of structures marks the considerable promise to the future application of phosphorus-nitrogen compounds

  10. Neutron diffraction by monocrystals of inorganic and elementary organic compounds

    International Nuclear Information System (INIS)

    Becker, G.; Hauser, H.D.

    1992-01-01

    The phase of preparation and X-ray structural analysis of the compounds has been completed following the synthetical preparation of compounds sensitive to oxidation and pyrolysis, in this case: phosphonic acid, potassium silanide, lithium dihydrogenphosphide * DME, bis[lithium-tri(tert.butyl)alanate], dibromophenylbismuthate, potassium tetrahydride aluminate, and phosphinic acid. The work was started is neutron diffraction experiments for detecting the positions of the hydrogen and carbon atoms, in order to analyse space group problems. (BBR) [de

  11. Selective oxidation of refractory sulfur compounds for the production of low sulfur transportation fuel

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Kwang-Eun; Kim, Tae-Wan; Kim, Joo-Wan; Chae, Ho-Jeong; Kim, Chul-Ung; Jeong, Soon-Yong [Korea Research Institute of Chemical Technology, Daejeon (Korea, Republic of); Park, Young-Kwon [University of Seoul, Seoul (Korea, Republic of)

    2013-03-15

    The current technologies for achieving low sulfur in diesel fuel are based on hydrotreating, which requires high temperature, high pressure and excessive supply of hydrogen. Oxidative desulfurization (ODS) is considered one of the promising new methods for super deep desulfurization, which could be carried out under very mild conditions (atmospheric pressure, <100 .deg.. C) without consumption of hydrogen. In this paper, development status of ODS process by major licensors are described as well as general concepts of ODS reaction. In addition, the ODS process has been categorized into single phasic and biphasic system according to the oxidants involved. Recent trends in both systems are reviewed in detail and future work is also proposed.

  12. Selective oxidation of refractory sulfur compounds for the production of low sulfur transportation fuel

    International Nuclear Information System (INIS)

    Jeong, Kwang-Eun; Kim, Tae-Wan; Kim, Joo-Wan; Chae, Ho-Jeong; Kim, Chul-Ung; Jeong, Soon-Yong; Park, Young-Kwon

    2013-01-01

    The current technologies for achieving low sulfur in diesel fuel are based on hydrotreating, which requires high temperature, high pressure and excessive supply of hydrogen. Oxidative desulfurization (ODS) is considered one of the promising new methods for super deep desulfurization, which could be carried out under very mild conditions (atmospheric pressure, <100 .deg.. C) without consumption of hydrogen. In this paper, development status of ODS process by major licensors are described as well as general concepts of ODS reaction. In addition, the ODS process has been categorized into single phasic and biphasic system according to the oxidants involved. Recent trends in both systems are reviewed in detail and future work is also proposed

  13. Experimental formation enthalpies for intermetallic phases and other inorganic compounds

    Science.gov (United States)

    Kim, George; Meschel, S. V.; Nash, Philip; Chen, Wei

    2017-01-01

    The standard enthalpy of formation of a compound is the energy associated with the reaction to form the compound from its component elements. The standard enthalpy of formation is a fundamental thermodynamic property that determines its phase stability, which can be coupled with other thermodynamic data to calculate phase diagrams. Calorimetry provides the only direct method by which the standard enthalpy of formation is experimentally measured. However, the measurement is often a time and energy intensive process. We present a dataset of enthalpies of formation measured by high-temperature calorimetry. The phases measured in this dataset include intermetallic compounds with transition metal and rare-earth elements, metal borides, metal carbides, and metallic silicides. These measurements were collected from over 50 years of calorimetric experiments. The dataset contains 1,276 entries on experimental enthalpy of formation values and structural information. Most of the entries are for binary compounds but ternary and quaternary compounds are being added as they become available. The dataset also contains predictions of enthalpy of formation from first-principles calculations for comparison. PMID:29064466

  14. Study on ionizing radiation effects in diesel and crude oil: organic compounds, hydrocarbon, sulfur and nitrogen

    International Nuclear Information System (INIS)

    Andrade, Luana dos Santos

    2014-01-01

    Petroleum is the most important energy and pollution source in the world, nowadays. New technologies in petrochemical industry aim to minimize energy spending at the process and to reduce pollution products. Sulfur and nitrogen compounds generate environmental problems; the most relevant is air pollution that affects the population health directly. The nuclear technology has been used in environmental protection through pollutants removal by free radicals produced at action of the radiation in water molecule. The objective of this study is to evaluate the radiation effects on oil and diesel, mainly in the hydrocarbons, organic sulfur, and nitrogen compounds. It was studied a molecule model of sulfur, named benzothiophene, diesel and crude oil samples. The samples were irradiated using a Co-60 source, Gammacell type. The total sulfur concentration in the samples was determined by X-ray fluorescence spectrometry, and organic compounds were analyzed by gas chromatography coupled to mass spectrometry (GC-MS). The study of molecular model showed that 95% was degraded at 20 kGy dose rate. Irradiation at 15 kGy of absorbed dose showed some cracking in petrol hydrocarbons, however with higher doses it was observed polymerization and low efficiency of cracking. It was observed that the sulfur compounds from diesel and petroleum was efficiently reduced. The applied doses of 15 kGy and 30 kGy were the most efficient on desulfurization of petroleum, and for diesel the highest variation was observed with 30 kGy and 50 kGy of absorbed dose. The distillation and chromatographic separation using an open column with palladium chloride as stationary phase showed a preferential separation of organic sulfur compounds in petroleum. (author)

  15. Sulfur ylides in the synthesis of heterocyclic and carbocyclic compounds

    International Nuclear Information System (INIS)

    Lakeev, Sergei N; Maydanova, Irina O; Galin, Fanur Z; Tolstikov, Genrikh A

    2001-01-01

    Data on the use of sulfonium ylides in the synthesis of carbocyclic and heterocyclic compounds published over the last 15 years are analysed, systematised and generalised. The bibliography includes 139 references.

  16. Cybernetic prediction of inorganic compounds and its correlation with experiment

    International Nuclear Information System (INIS)

    Savitskiy, E.M.; Gribulya, V.B.; Kiselyova, N.N.

    1982-01-01

    Using known experimental examples and data on chemical elements, an approach was proposed, based on computer learning, to establish the regularities and to predict the character of interaction of components of physico-chemical systems of the type AB, A 2 B, and A 3 B. A review is given of the predicted compounds and phases in order to demonstrate the applicability of the method

  17. Contribution of sulfuric acid and oxidized organic compounds to particle formation and growth

    Directory of Open Access Journals (Sweden)

    F. Riccobono

    2012-10-01

    Full Text Available Lack of knowledge about the mechanisms underlying new particle formation and their subsequent growth is one of the main causes for the large uncertainty in estimating the radiative forcing of atmospheric aerosols in global models. We performed chamber experiments designed to study the contributions of sulfuric acid and organic vapors to the formation and early growth of nucleated particles. Distinct experiments in the presence of two different organic precursors (1,3,5-trimethylbenzene and α-pinene showed the ability of these compounds to reproduce the formation rates observed in the low troposphere. These results were obtained measuring the sulfuric acid concentrations with two chemical ionization mass spectrometers confirming the results of a previous study which modeled the sulfuric acid concentrations in presence of 1,3,5-trimethylbenzene.

    New analysis methods were applied to the data collected with a condensation particle counter battery and a scanning mobility particle sizer, allowing the assessment of the size resolved growth rates of freshly nucleated particles. The effect of organic vapors on particle growth was investigated by means of the growth rate enhancement factor (Γ, defined as the ratio between the measured growth rate in the presence of α-pinene and the kinetically limited growth rate of the sulfuric acid and water system. The observed Γ values indicate that the growth is already dominated by organic compounds at particle diameters of 2 nm. Both the absolute growth rates and Γ showed a strong dependence on particle size, supporting the nano-Köhler theory. Moreover, the separation of the contributions from sulfuric acid and organic compounds to particle growth reveals that the organic contribution seems to be enhanced by the sulfuric acid concentration. Finally, the size resolved growth analysis indicates that both condensation of oxidized organic compounds and reactive uptake contribute to particle growth.

  18. Development of an Analytic Method for Sulfur Compounds in Aged Garlic Extract with the Use of a Postcolumn High Performance Liquid Chromatography Method with Sulfur-Specific Detection.

    Science.gov (United States)

    Matsutomo, Toshiaki; Kodera, Yukihiro

    2016-02-01

    Garlic and its processed preparations contain numerous sulfur compounds that are difficult to analyze in a single run using HPLC. The aim of this study was to develop a rapid and convenient sulfur-specific HPLC method to analyze sulfur compounds in aged garlic extract (AGE). We modified a conventional postcolumn HPLC method by employing a hexaiodoplatinate reagent. Identification and structural analysis of sulfur compounds were conducted by LC-mass spectrometry (LC-MS) and nuclear magnetic resonance. The production mechanisms of cis-S-1-propenylcysteine (cis-S1PC) and S-allylmercaptocysteine (SAMC) were examined by model reactions. Our method has the following advantages: less interference from nonsulfur compounds, high sensitivity, good correlation coefficients (r > 0.98), and high resolution that can separate >20 sulfur compounds, including several isomers, in garlic preparations in a single run. This method was adapted for LC-MS analysis. We identified cis-S1PC and γ-glutamyl-S-allyl-mercaptocysteine in AGE. The results of model reactions suggest that cis-S1PC is produced from trans-S1PC through an isomerization reaction and that SAMC is produced by a reaction involving S-allylcysteine/S1PC and diallyldisulfide during the aging period. We developed a rapid postcolumn HPLC method for both qualitative and quantitative analyses of sulfur compounds, and this method helped elucidate a potential mechanism of cis-S1PC and SAMC action in AGE. © 2016 American Society for Nutrition.

  19. Inhibition of Enzymatic Browning of Chlorogenic Acid by Sulfur-Containing Compounds

    NARCIS (Netherlands)

    Kuijpers, T.F.M.; Narvaez Cuenca, C.E.; Vincken, J.P.; Verloop, J.W.; Berkel, van W.J.H.; Gruppen, H.

    2012-01-01

    The antibrowning activity of sodium hydrogen sulfite (NaHSO3) was compared to that of other sulfur-containing compounds. Inhibition of enzymatic browning was investigated using a model browning system consisting of mushroom tyrosinase and chlorogenic acid (5-CQA). Development of brown color

  20. Removal of H2S and volatile organic sulfur compounds by silicone membrane extraction

    NARCIS (Netherlands)

    Manconi, I.; Lens, P.N.L.

    2009-01-01

    BACKGROUND: This study explores an alternative process for the abatement and/or desulfurization of H2S and volatile organic sulfur compounds (VOSC) containing waste streams, which employs a silicone-based membrane to simultaneously remove H2S and VOSC. An extractive membrane reactor allows the

  1. Volatile Organic Sulfur Compounds of Environmental Interest: Dimethyl Sulfide and Methanethiol

    Science.gov (United States)

    Chasteen, Thomas G.; Bentley, Ronald

    2004-01-01

    Volatile organic sulfur compounds (VOSCs) have been assigned environmental roles in global warming, acid precipitation, and cloud formation where two important members dimethyl sulfide (CH3)2 S, DMS, and methanethiol, CH3SH, MT, of VOSC group are involved.

  2. Enhanced fatty acid production in engineered chemolithoautotrophic bacteria using reduced sulfur compounds as energy sources

    DEFF Research Database (Denmark)

    Beller, Harry R.; Zhou, Peng; Jewell, Talia N.M.

    2016-01-01

    Chemolithoautotrophic bacteria that oxidize reduced sulfur compounds, such as H2S, while fixing CO2 are an untapped source of renewable bioproducts from sulfide-laden waste, such as municipal wastewater. In this study, we report engineering of the chemolithoautotrophic bacterium Thiobacillus...

  3. Analysis of hydrogen, carbon, sulfur and volatile compounds in (U3Si2 - Al) nuclear fuel

    International Nuclear Information System (INIS)

    Moura, Sergio C.; Redigolo, Marcelo M.; Amaral, Priscila O.; Leao, Claudio; Oliveira, Glaucia A.C. de; Bustillos, Oscar V.

    2015-01-01

    Uranium silicide U 3 Si 2 is used as nuclear fuel in the research nuclear reactor IEA-R1 at IPEN/CNEN, Sao Paulo, Brazil. The U 3 Si 2 is dispersed in aluminum reaching high densities of uranium in the nucleus of the fuel, up to 4.8 gU cm -3 . This nuclear fuel must comply with a quality control, which includes analysis of hydrogen, carbon and sulfur for the U 3 Si 2 and volatile compound for the aluminum. Hydrogen, carbon and sulfur are analyzed by the method of Radio Frequency gas extraction combustion coupled with Infrared detector. Volatile compounds are analyzed by the method of heated gas extraction coupled with gravimetric measurement. These methods are recommended by the American Society for Testing Materials (ASTM) for nuclear materials. The average carbon and sulfur measurements are 30 μg g -1 and 3 μg g -1 , respectively, and 40 μg g -1 for volatile compounds. The hydrogen analyzer is a TCHEN 600 LECO, carbon and sulfur analyzer is a CS 244 LECO and the volatile compounds analyzer is a home-made apparatus that use a resistant furnace, a gas pipe measurement and a glove-box with controlled atmosphere where an analytical balance has been installed, this analyzer was made at IPEN laboratory. (author)

  4. Efficacy of HOCl scavenging by sulfur-containing compounds: antioxidant activity of glutathione disulfide?

    NARCIS (Netherlands)

    den Hartog, G.J.M.; Haenen, G.R.M.M.; Vegt, E.; van der Vijgh, W.J.F.; Bast, A.

    2002-01-01

    Efficacy of HOCl scavenging by sulfur-containing compounds: antioxidant activity of glutathione disulfide? den Hartog GJ, Haenen GR, Vegt E, van der Vijgh WJ, Bast A. Department of Pharmacology and Toxicology, Maastricht University, The Netherlands. Hypochlorous acid (HOCl) is a bactericidal

  5. Nomenclature and spelling rules of chemistry in Hungary Pt. 1 Nomenclature of elements and inorganic compounds

    International Nuclear Information System (INIS)

    Fodorne Csanyi, P.

    1982-01-01

    The part of the updated edition of 'Nomenclature and spelling rules of chemistry in Hungary' (Budapest, 1972), referring to the isotopically modified inorganic compounds is presented. The rules are based on the proposals of IUPAC (1981). Spelling rules concerning the isotopically substituted, isotopically labelled, specifically labelled, selectively and non-selectively labelled compounds, and the positional and numbering rules of nuclides are treated. (Sz.J.)

  6. A golden future in medicinal inorganic chemistry : The promise of anticancer gold organometallic compounds

    NARCIS (Netherlands)

    Bertrand, B.; Casini, A.

    2014-01-01

    From wedding rings on fingers to stained glass windows, by way of Olympic medals, gold has been highly prized for millennia. Nowadays, organometallic gold compounds occupy an important place in the field of medicinal inorganic chemistry due to their unique chemical properties with respect to gold

  7. Capillary electrophoretic separation of inorganic and organic arsenic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Greschonig, H. [Institute of Analytical Chemistry, Karl Franzens University Graz (Austria); Schmid, M.G.; Guebitz, G. [Institute of Pharmaceutical Chemistry, Karl Franzens University Graz (Austria)

    1998-09-01

    Capillary zone electrophoresis was used to separate arsenite, arsenate, dimethylarsinic and diphenylarsinic acid, methanearsonic acid, phenyl- and p-aminophenyl arsonic acid, phenylarsineoxide and phenarsazinic acid. Anionic and uncharged species were separated in a fused silica capillary with on-column UV detection at 200 nm. A 15 mM phosphate solution adjusted to pH 6.5 containing 10 mM sodium dodecylsulfonate served as background electrolyte. The influence of pH and applied voltage on separation efficiency, as well as the feasibility of identification of arsenic compounds in spiked urine, were investigated. (orig.) With 7 figs., 1 tab., 22 refs.

  8. Preliminary results of measurements of air pollution caused by sulfur compounds near the Polaniec power plant

    Energy Technology Data Exchange (ETDEWEB)

    Dziewanski, J; Kasina, S; Lewinska, J; Piorek, S

    1976-01-01

    In the past investigations of the negative impact of power stations on the natural environment have been restricted to measuring sulfur dioxide content in the air. A method of determining complex influence of sulfur compounds on the natural environment is proposed. The following indexes are used: content of sulfur dioxide in the air, dust content (determined by means of the West-Gaeke method), content of sulphate ions in precipitation and pH value of precipitation. Methods used to determine each of the indexes are described. Location of measuring stations in the area where the power station is being constructed is evaluated, taking into account prevailing wind direction and atmospheric conditions (15 measuring points out of which 10 stations measure sulfur content in precipitation and pH value of precipitation, and 5 stations measure the mean daily concentration of sulfur dioxide and dust content). Results are presented in 3 maps, 1 table and 2 pictures. Variations in sulfur dioxide content, dust content, and pH value of precipitation depending on direction of wind, atmospheric conditions and season are analyzed. The results of the investigation will be compared with results of investigations carried out when the power station is in operation. (15 refs.)

  9. Sulfur-containing heterocyclic compounds with potential antidiabetic activity

    Directory of Open Access Journals (Sweden)

    E. A. Savateeva

    2014-12-01

    Full Text Available The essential link in the pathogenesis of diabetes mellitus and its complications is a non-enzymatic glycosylation of proteins. However, modern endocrinology lacks of clinically effective pharmaceuticals for its correction. The screening of 23 derivatives of 1,3,4-thiadiazine the ability to inhibit the reaction of non-enzymatic glycosylation of proteins in vitro was held, and 11 the most active compounds of them were selected, also the relationship «structure – activity» was investigated. An essential part of the pathogenesis of diabetes mellitus and its complications is non-enzymatic glycosylation of proteins. However, modern endocrinology lacks clinically effective medicines for its correction.

  10. Atmospheric chemistry of organic sulfur and nitrogen compounds

    International Nuclear Information System (INIS)

    Nielsen, O.J.; Sidebottom, H.W.; Treacy, J.J.

    1988-12-01

    The work carried out during the first year of a four year Danish-Irish contract with the European Economic Community is described. The reactions of OH radicals with dialkyl sulfides and nitroalkanes have been studied applying both an absolute technique of pulse radiolysis with kinetic spectroscopy and a relative rate method using conventional smog chamber facilities. The reactions of OH with dimethyl sulfide and nitromethane have been investigated in special detail. Rate constants for reaction of Cl atoms with the same compounds have been determing using the relative rate method. (author)

  11. Comparison of comprehensive two-dimensional gas chromatography coupled with sulfur-chemiluminescence detector to standard methods for speciation of sulfur-containing compounds in middle distillates.

    Science.gov (United States)

    Ruiz-Guerrero, Rosario; Vendeuvre, Colombe; Thiébaut, Didier; Bertoncini, Fabrice; Espinat, Didier

    2006-10-01

    The monitoring of total sulfur content and speciation of individual sulfur-containing compounds in middle distillates is required for efficient catalyst selection and for a better understanding of the kinetics of the reactions involved in hydrotreament processes. Owing to higher resolution power and enhanced sensitivity, comprehensive two-dimensional gas chromatography (GCxGC) hyphenated to sulfur chemiluminescence detection (SCD) has recently evolved as a powerful tool for improving characterization and identification of sulfur compounds. The aim of this paper is to compare quantitatively GCxGC-SCD and various other methods commonly employed in the petroleum industry, such as X-ray fluorescence, conventional GC-SCD, and high-resolution mass spectrometry, for total sulfur content determination and speciation analysis. Different samples of middle distillates have been analyzed to demonstrate the high potential and important advantages of GCxGC-SCD for innovative and quantitative analysis of sulfur-containing compounds. More accurate and detailed results for benzothiophenes and dibenzothiophenes are presented, showing that GCxGC-SCD should become, in the future, an essential tool for sulfur speciation analysis.

  12. Synthesis and biological activity of sulfur compounds showing structural analogy with combretastatin A-4

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Edson dos A. dos; Prado, Paulo C.; Carvalho, Wanderley R. de; Lima, Ricardo V. de; Beatriz, Adilson; Lima, Denis P. de, E-mail: denis.lima@ufms.br [Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande, MS (Brazil). Departamento de Quimica; Hamel, Ernest [Screening Technologies Branch, Developmental Therapeutics Program, Division of Cancer Treatment and Diagnosis, National Cancer Institute at Frederick, National Institutes of Health, Frederick, MD (United States); Dyba, Marzena A. [Basic Science Program , SAIC-Frederick, Inc., Structural Biophysics Laboratory National Cancer Institute, Frederick, MD (United States); Albuquerque, Sergio [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas

    2013-09-01

    We extended our previous exploration of sulfur bridges as bioisosteric replacements for atoms forming the bridge between the aromatic rings of combretastatin A-4. Employing coupling reactions between 5-iodo-1,2,3-trimethoxybenzene and substituted thiols, followed by oxidation to sulfones with m-CPBA, different locations for attaching the sulfur atom to ring A through the synthesis of nine compounds were examined. Antitubulin activity was performed with electrophoretically homogenous bovine brain tubulin, and activity occurred with the 1,2,3-trimethoxy-4-[(4-methoxyphenyl)thio]benzene (12), while the other compounds were inactive. The compounds were also tested for leishmanicidal activity using promastigote forms of Leishmania braziliensis (MHOM/BR175/M2904),and the greatest activity was observed with 1,2,3-trimethoxy-4-(phenylthio)benzene (10) and 1,2,3-trimethoxy-4-[(4-methoxyphenyl) sulfinyl]benzene (15). (author)

  13. [Responses of rice-wheat rotation system in south Jiangsu to organic-inorganic compound fertilizers].

    Science.gov (United States)

    Tian, Heng-Da; Zhang, Li; Zhang, Jian-Chao; Wang, Qiu-Jun; Xu, Da-Bing; Yibati, Halihashi; Xu, Jia-Le; Huang, Qi-Wei

    2011-11-01

    In 2006-2007, a field trial was conducted to study the effects of applying three kinds of organic-inorganic compound fertilizers [rapeseed cake compost plus inorganic fertilizers (RCC), pig manure compost plus inorganic fertilizers (PMC), and Chinese medicine residues plus inorganic fertilizers (CMC)] on the crop growth and nitrogen (N) use efficiency of rice-wheat rotation system in South Jiangsu. Grain yield of wheat and rice in the different fertilization treatments was significantly higher than the control (no fertilization). In treatments RCC, PMC and CMC, the wheat yield was 13.1%, 32.2% and 39.3% lower than that of the NPK compound fertilizer (CF, 6760 kg x hm(-2)), respectively, but the rice yield (8504-9449 kg x hm(-2)) was significantly higher than that (7919 kg x hm(-2)) of CF, with an increment of 7.4%-19.3%. In wheat season, the aboveground dry mass, N accumulation, and N use efficiency in treatments RCC, PMC, and CMC were lower than those of CF, but in rice season, these parameters were significantly higher than or as the same as CF. In sum, all the test three compound fertilizers had positive effects on the rice yield and its nitrogen use efficiency in the rice-wheat rotation system, being most significant for RCC.

  14. Matrix- and tensor-based recommender systems for the discovery of currently unknown inorganic compounds

    Science.gov (United States)

    Seko, Atsuto; Hayashi, Hiroyuki; Kashima, Hisashi; Tanaka, Isao

    2018-01-01

    Chemically relevant compositions (CRCs) and atomic arrangements of inorganic compounds have been collected as inorganic crystal structure databases. Machine learning is a unique approach to search for currently unknown CRCs from vast candidates. Herein we propose matrix- and tensor-based recommender system approaches to predict currently unknown CRCs from database entries of CRCs. Firstly, the performance of the recommender system approaches to discover currently unknown CRCs is examined. A Tucker decomposition recommender system shows the best discovery rate of CRCs as the majority of the top 100 recommended ternary and quaternary compositions correspond to CRCs. Secondly, systematic density functional theory (DFT) calculations are performed to investigate the phase stability of the recommended compositions. The phase stability of the 27 compositions reveals that 23 currently unknown compounds are newly found to be stable. These results indicate that the recommender system has great potential to accelerate the discovery of new compounds.

  15. Moessbauer spectroscopic study on inorganic compounds. Pt. 2

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Masashi; Kitazawa, Takafumi; Nanba, Hiroshi; Yoshinaga, Tomohiro; Nakajima, Norio; Sumisawa, Yasuhiro; Takeda, Masuo [Toho Univ., Funabashi, Chiba (Japan). Faculty of Science; Sawahata, Hiroyuki; Ito, Yasuo

    1998-01-01

    {sup 166}Er and {sup 127}I Moessbauer spectra were observed. {sup 166}Er Moessbauer spectrum of Er metal and 9 compounds were measured by {sup 166}Ho/Y{sub 0.6}Ho{sub 0.4}H{sub 2} source at 12K and the parameters such as e{sup 2}qQ(mm s{sup -1}), Heff(T) and {tau}(ns) were determined. The relaxation time of ErCl{sub 3}{center_dot}6H{sub 2}O was 0.7ns, long, but that of ErCl{sub 3} was 10 ps, short time. {sup 127}I Moessbauer spectrum of PhI(O{sub 2}CR){sub 2} (R=CH{sub 3}, CHF{sub 2}, CH{sub 2}Cl, CHCl{sub 2}, CCl{sub 3}, CH{sub 2}Br, CHBr{sub 2} and CBr{sub 3}) were observed and compared with that of R`{sub 3}Sb(O{sub 2}CR){sub 2} was similar to that of PhI(O{sub 2}CR){sub 2}. The correlation coefficient between e{sup 2}qQ({sup 127}I) and Mulliken population of carboxylic hydrogen atom of R{sub 2}CO{sub 2}H was -0.87. The relation between the hypervalent bond of O-I-O and that of O-Sb-0 was shown by the equation: e{sup 2}qQ({sup 121}Sb)/mm s{sup -1} = -47.2 + 1.32 e{sup 2}qQ({sup 127}I)/mm s{sup -1}. Hypervalent iodine complex such as (PhI(py){sub 2}){sup 2+} salt and E-Sb-I (E=O, I, N and C) were studied, too. (S.Y.)

  16. Microbial oxidation and reduction of inorganic sulphur compounds in relation to the development and control of microorganisms active in leaching operations. Part of a coordinated programme on bacterial leaching of uranium ores

    International Nuclear Information System (INIS)

    Tuovinen, O.H.

    1977-01-01

    The project considers the use of Thiobacillus ferroxidans type bacteria for the leaching of metals from ores. The various ways by which Thiobacillus ferroxidans utilizes inorganic sulfur compounds for oxidation, energy, growth and synthesis of cellular material were studied. The report briefly describes the scope and background of the project, and a list of publications describing experimental methods and research materials used is given. Unpublished work commenced during the Research Contract includes three major projects: (1) Transition of Thiobacillus ferroxidans from heterotrophic growth on fucose to autotropic growth on ferrous-iron; (2) development of a method to determine the ATP-content of bacteria attached to ore particles; (3) microbiological and chemical interactions of inorganic sulfur compounds. These three projects are summarized briefly

  17. The influence of biogenic atmospheric sulfur compounds on climate

    Energy Technology Data Exchange (ETDEWEB)

    Georgii, H -W [University of Frankfurt am Main, Frankfurt am Main (Germany). Dept. of Meteorology and Geophysics

    1993-09-01

    The author reviews research so far into sulphur compounds occurring in the atmosphere, namely dimethylsulfide (DMS) and carbonyl sulphide (COS). He explains how the sulphate particles formed by oxidation of DMS with OH radicals act as cloud condensation nuclei which in turn leads to enhanced formation of precipitation. Increase of cloud droplet density leads also to an increase of cloud albedo. The hypothesis of carbonyl sulphide as a precursor for stratospheric sulphate particles is discussed, along with evidence of model calculations showing that the increase of COS flux in the stratosphere leads to an increase in density of stratospheric aerosols and to slight global cooling, particularly compensating for the warming caused by the greenhouse effect. Although the influence of biogenic sulphur gases on climate is still speculative due to lack of information of the source, strength and global trend of these gases, the author advocates they deserve special attention since they may contribute to the stabilization of our climate. 16 refs., 5 figs.

  18. Sulfur equilibrium desulfurization of sulfur containing products of combustion

    International Nuclear Information System (INIS)

    Woodroffe, J.A.; Abichandani, J.S.

    1990-01-01

    This patent describes the method for the combustion of a carbon- and sulfur-containing fuel for substantially reducing emission of gaseous sulfur compounds formed during combustion of the fuel in a combustion zone. The zone having one or more fuel inlets and one or more oxidizer inlets, and having a combustion products outlet spaced therefrom, and having one or more inorganic sorbent inlets downstream of the fuel inlet(s) and oxidizer inlet(s) and upstream of the combustion products outlet

  19. Synthesis and Odor Evaluation of Five New Sulfur-Containing Ester Flavor Compounds from 4-Ethyloctanoic Acid

    Directory of Open Access Journals (Sweden)

    Baoguo Sun

    2010-07-01

    Full Text Available Five sulfur-containing flavor compounds were synthesized for the first time by the reaction of 4-ethyloctanoyl chloride with sulfur-containing alcohols or mercaptans. The synthesized compounds are 3-(methylthiopropyl 4-ethyloctanoate, 2-methyl-3-tetrahydro-furanthiol 4-ethyloctanoate, 4-methyl-5-thiazoleethanol 4-ethyloctanoate, 2-furan-methanethiol 4-ethyloctanoate and 2-methyl-3-furanthiol 4-ethyloctanoate. These five synthetic sulfur-containing ester flavor compounds all have meaty odor and might be used in foods if approved for this purpose in the future.

  20. Synthesis and odor evaluation of five new sulfur-containing ester flavor compounds from 4-ethyloctanoic acid.

    Science.gov (United States)

    Liu, Yuping; Chen, Haitao; Yin, Decai; Sun, Baoguo

    2010-07-29

    Five sulfur-containing flavor compounds were synthesized for the first time by the reaction of 4-ethyloctanoyl chloride with sulfur-containing alcohols or mercaptans. The synthesized compounds are 3-(methylthio)propyl 4-ethyloctanoate, 2-methyl-3-tetrahydro-furanthiol 4-ethyloctanoate, 4-methyl-5-thiazoleethanol 4-ethyloctanoate, 2-furan-methanethiol 4-ethyloctanoate and 2-methyl-3-furanthiol 4-ethyloctanoate. These five synthetic sulfur-containing ester flavor compounds all have meaty odor and might be used in foods if approved for this purpose in the future.

  1. Possibilities of analyzing dump and sewage gas, and determination of halogen and sulfur compounds

    Energy Technology Data Exchange (ETDEWEB)

    Eisenmann, R

    1985-01-01

    In connection with the utilization of refuse and sewage gas efficacions analytical methods are gaining increasing importance especially with regard to halogen and sulfur compounds. The paper describes various possibilities to determine those substances. Besides gas chromatography it takes into account classic analytical methods which can be superior in biogas analytics to modern physical processes. The advantages and disadvantages of each method are discussed and practical experiences obtained by their application reported.

  2. U6+ minerals and inorganic compounds: insights into an expanded structural hierarchy of crystal structures

    International Nuclear Information System (INIS)

    Burns, P.C.

    2005-01-01

    The crystal structures of uranyl minerals and inorganic uranyl compounds are important for understanding the genesis of U deposits, the interaction of U mine and mill tailings with the environment, transport of actinides in soils and the vadose zone, the performance of geological repositories for nuclear waste, and for the development of advanced materials with novel applications. Over the past decade, the number of inorganic uranyl compounds (including minerals) with known structures has more than doubled, and reconsideration of the structural hierarchy of uranyl compounds is warranted. Here, 368 inorganic crystal structures that contain essential U 6+ are considered (of which 89 are minerals). They are arranged on the basis of the topological details of their structural units, which are formed by the polymerization of polyhedra containing higher-valence cations. Overarching structural categories correspond to those based upon isolated polyhedra (8), finite clusters (43), chains (57), sheets (204), and frameworks (56) of polyhedra. Within these categories, structures are organized and compared upon the basis of either their graphical representations, or in the case of sheets involving sharing of edges of polyhedra, upon the topological arrangement of anions within the sheets. (author)

  3. Inorganic elements and organic compounds degradation studies by gamma irradiation in used lubricating oils

    International Nuclear Information System (INIS)

    Scapin, Marcos Antonio

    2008-01-01

    The automotive lubricating oils have partial degradation of organic compounds and addition of undesirable inorganic elements, during its use. These substances classify the used lubricating oils as dangerous and highly toxic. According to global consensus, concerning the environmental conservation, the best is to perform a reuse treatment of these lubricating oils. For this purpose, the uses of an alternative and effective technology have been sought. In this work, the efficacy and technical feasibility of the advanced oxidation process (AOP), by gamma radiation, for used automotive lubricating oil treatment has been studied. Different quantities of hydrogen peroxide and water Milli-Q were added to oil samples. They were submitted to the Cobalt-60 irradiator, type Gammacell, with 100, 200 and 500 kGy absorbed doses. The inorganic analysis by X-ray fluorescence (WDXRF) showed inorganic elements removal, mainly to sulphur, calcium, iron and nickel elements at acceptable levels by environmental protection law for oils reusing. The gas chromatography (GC/MS) analysis showed that the advanced oxidation process promotes the organic compounds degradation. The main identified compounds were tridecane, 2-methyl-naphthalene, and trietilamina-tetramethyl urea, which have important industrial applications. The multivariate analysis, Cluster Analysis, showed that advanced oxidation process application is a viable and promising treatment for used lubricating oil reusing. (author)

  4. Development of conjugate methods with gas chromatography for inorganic compounds analysis

    International Nuclear Information System (INIS)

    Baccan, N.

    1975-01-01

    The application of gas chromatography combined with mass spectrometry or with nuclear methods for the analysis of inorganic compounds is studied. The advantages of the use of a gas chromatograph coupled with a quadrupole mass spectrometer or with a high resolution radiation detector, are discussed. We also studied the formation and solvent extraction of metal chelates; an aliquot of the organic phase was directly injected into the gas chromatograph and the eluted compounds were detected by mass spectrometry or, when radioactive, by nuclear methods. (author)

  5. Scintillating Organic–Inorganic Layered Perovskite-type Compounds and the Gamma-ray Detection Capabilities

    OpenAIRE

    Kawano, Naoki; Koshimizu, Masanori; Okada, Go; Fujimoto, Yutaka; Kawaguchi, Noriaki; Yanagida, Takayuki; Asai, Keisuke

    2017-01-01

    We investigated scintillation properties of organic–inorganic layered perovskite-type compounds under gamma-ray and X-ray irradiation. A crystal of the hybrid compounds with phenethyl amine (17 × 23 × 4 mm) was successfully fabricated by the poor-solvent diffusion method. The bulk sample showed superior scintillation properties with notably high light yield (14,000 photons per MeV) under gamma-rays and very fast decay time (11 ns). The light yield was about 1.4 time higher than that of common...

  6. Long-term trends in total inorganic nitrogen and sulfur deposition in the US from 1990 to 2010

    Directory of Open Access Journals (Sweden)

    Y. Zhang

    2018-06-01

    Full Text Available Excess deposition (including both wet and dry deposition of nitrogen and sulfur is detrimental to ecosystems. Recent studies have investigated the spatial patterns and temporal trends of nitrogen and sulfur wet deposition, but few studies have focused on dry deposition due to the scarcity of dry deposition measurements. Here, we use long-term model simulations from the coupled Weather Research and Forecasting and the Community Multiscale Air Quality (WRF-CMAQ model covering the period from 1990 to 2010 to study changes in spatial distribution as well as temporal trends in total (TDEP, wet (WDEP, and dry deposition (DDEP of total inorganic nitrogen (TIN and sulfur (TS in the United States (US. We first evaluate the model's performance in simulating WDEP over the US by comparing the model results with observational data from the US National Atmospheric Deposition Program. The coupled model generally underestimates the WDEP of both TIN (including both the oxidized nitrogen deposition, TNO3, and the reduced nitrogen deposition, NHx and TS, with better performance in the eastern US than the western US. The underestimation of the wet deposition by the model is mainly caused by the coarse model grid resolution, missing lightning NOx emissions, and the poor temporal and spatial representation of NH3 emissions. TDEP of both TIN and TS shows significant decreases over the US, especially in the east, due to the large emission reductions that occurred in that region. The decreasing trends of TIN TDEP are caused by decreases in TNO3, and the increasing trends of TIN deposition over the Great Plains and Tropical Wet Forests (Southern Florida Coastal Plain regions are caused by increases in NH3 emissions, although it should be noted that these increasing trends are not significant. TIN WDEP shows decreasing trends throughout the US, except for the Marine West Coast Forest region. TIN DDEP shows significant decreasing trends in the Eastern Temperate Forests

  7. Adsorption of sulfur compound utilizing rice husk ash modified with niobium

    Energy Technology Data Exchange (ETDEWEB)

    Cavalcanti, Rodrigo M.; Pessoa Júnior, Wanison A.G. [Laboratório de Catálise Química e Materiais (CATAMA), Instituto de Ciências Exatas, Universidade Federal do Amazonas (UFAM), Av. Gen. Rodrigo Otávio Jordão Ramos, 6200, 69077-000 Manaus, AM (Brazil); Braga, Valdeilson S. [Laboratório de Catálise, Centro das Ciências Exatas e das Tecnologias, Universidade Federal do Oeste da Bahia, Rua Professor José Seabra de Lemos, 316, Recanto dos Pássaros, 47808-021 Barreira, BA (Brazil); Barros, Ivoneide de C.L., E-mail: iclbarros@gmail.com [Laboratório de Catálise Química e Materiais (CATAMA), Instituto de Ciências Exatas, Universidade Federal do Amazonas (UFAM), Av. Gen. Rodrigo Otávio Jordão Ramos, 6200, 69077-000 Manaus, AM (Brazil)

    2015-11-15

    Graphical abstract: - Highlights: • Adsorbents based in RHA modified with niobium were prepared by impregnation. • The impregnation modified the particle size and topology of RHA particles. • The adsorbents were applied in sulfur removal in model liquid fuels. • The larger sulfur removal (>50%) was achieved using RHA with 5 wt.% niobium oxide. • The adsorbent show great selectivity in adsorption experiments. - Abstract: Adsorbents based in rice husk ash (RHA) modified with niobium pentoxide were prepared for impregnation methods and applied in sulfur removal in liquid fuels. The solids were characterized by X-ray diffraction, infrared spectroscopy, scanning electron microscopy, nitrogen physisorption and thermal analysis; they show that there was no qualitative change in the amorphous structure of the RHA; however, the method of impregnation could modify the particle size and topology of RHA particles. The larger sulfur removal (>50%) was achieved using RHA with 5 wt.% Nb{sub 2}O{sub 5} at a dosage of 10 g L{sup −1}, after 4 h of contact with the model fuel. The kinetic study of adsorption of thiophene showed that the models of pseudo-second order and intra-particle diffusion best fit the experimental data. The adsorption experiments with the thiophenic derivatives compounds show a large selectivity of the adsorbent.

  8. Adsorption of sulfur compound utilizing rice husk ash modified with niobium

    International Nuclear Information System (INIS)

    Cavalcanti, Rodrigo M.; Pessoa Júnior, Wanison A.G.; Braga, Valdeilson S.; Barros, Ivoneide de C.L.

    2015-01-01

    Graphical abstract: - Highlights: • Adsorbents based in RHA modified with niobium were prepared by impregnation. • The impregnation modified the particle size and topology of RHA particles. • The adsorbents were applied in sulfur removal in model liquid fuels. • The larger sulfur removal (>50%) was achieved using RHA with 5 wt.% niobium oxide. • The adsorbent show great selectivity in adsorption experiments. - Abstract: Adsorbents based in rice husk ash (RHA) modified with niobium pentoxide were prepared for impregnation methods and applied in sulfur removal in liquid fuels. The solids were characterized by X-ray diffraction, infrared spectroscopy, scanning electron microscopy, nitrogen physisorption and thermal analysis; they show that there was no qualitative change in the amorphous structure of the RHA; however, the method of impregnation could modify the particle size and topology of RHA particles. The larger sulfur removal (>50%) was achieved using RHA with 5 wt.% Nb 2 O 5 at a dosage of 10 g L −1 , after 4 h of contact with the model fuel. The kinetic study of adsorption of thiophene showed that the models of pseudo-second order and intra-particle diffusion best fit the experimental data. The adsorption experiments with the thiophenic derivatives compounds show a large selectivity of the adsorbent.

  9. Chemical protection of bacteria and cultured mammalian cells by sulfur--containing compounds

    Energy Technology Data Exchange (ETDEWEB)

    Antoku, S [Hiroshima Univ. (Japan). Research Inst. for Nuclear Medicine and Biology

    1975-03-01

    Protection by sulfur-containing compounds was studied using bacteria E. coli Bsub(H) and cultured mouse leukemic cells, L 5178 Y. The protective mechanisms are discussed. The dose reduction factors of non-sulfhydryl compounds observed in the bacteria were the same as those observed in mammalian cells, and the protective activity of these compounds was proportional to their reaction rates with hydroxyl radicals. On the other hand, sulfhydryl compounds, with the exception of glutathione, offered a much greater protection than was anticipated from their radical scavenging activity. From studies under anoxia, the protection of cysteine was explained by its OH scavenging and competition with oxygen. In addition, for MEA, protection against the direct action of radiation was suggested. This was supported by the significant protection in the frozen state.

  10. Influence of Inorganic Ions and Organic Substances on the Degradation of Pharmaceutical Compound in Water Matrix

    Directory of Open Access Journals (Sweden)

    Edyta Kudlek

    2016-11-01

    Full Text Available The paper determined the influence of inorganic substances and high-molecular organic compounds on the decomposition of diclofenac, ibuprofen, and carbamazepine in the process of photocatalysis conducted with the presence of Titanium dioxide (TiO2. It was determined that the presence of such ions as CO 3 2 − , HCO 3 − , HPO 4 2 − as well as SO 4 2 − inhibited the decomposition of carbamazepine, whereas the efficiency of diclofenac degradation was decreased only by the presence of CO 3 2 − and HCO 3 − anions. In case of ibuprofen sodium salt (IBU, all investigated anions influenced the increase in its decomposition rate. The process of pharmaceutical photooxidation conducted in suspensions with Al3+ and Fe3+ cations was characterized by a significantly decreased efficiency when compared to the solution deprived of inorganic compounds. The addition of Ca2+, Mg2+ and NH4+ affected the increase of reaction rate constant value of diclofenac and ibuprofen decomposition. On the other hand, high molecular organic compounds present in the model effluent additionally catalysed the degradation process of pharmaceutical compounds and constituted an additional sorbent that enabled to decrease their concentration. Toxicological analysis conducted in deionized water with pharmaceutical compounds’ patterns proved the production of by-products from oxidation and/or reduction of micropollutants, which was not observed for model effluent irradiation.

  11. In vitro cytogenetic testing of an organoselenium compound and its sulfur analogue in cultured rat bone marrow cells

    Directory of Open Access Journals (Sweden)

    Jacob Jacob H

    2004-03-01

    Full Text Available Abstract Background Selenium (Se is a non-metal element, occurring in varying degrees in the environment and it has been found to be a component of several enzymes. Different selenium compounds have been associated with carcinogenicity, toxicity, modification of metal toxicity and prevention of cancer. Organoselenium compounds had substantially greater bioavailability and less toxicity than that of inorganic selenium. From a chemical point of view, Se resembles sulfur (S in many of its properties, thus, Se and S may be considered to be isosteric. The ability of a synthetic organoselenium compound; cyclopenta-dienyldicarbonyl ironselenoterephthalic acid (CSe and its sulfur analogue (CS in the range of 10-8 to 10-5 M, to induce sister-chormatid exchanges (SCE and alter cell division expressed as mitotic index (MI as well as cell survival has been investigated. Methods Rat bone marrow cells were cultured in the presence of CSe and CS in the range of 10-8 to 10-5 M with a total exposure time of 4, 16 or 28 h at 37°C. Fluorescence-plus-Giemsa (FPG technique was used to visualize chromosomes for SCE analysis and MI determination. Trypan blue exclusion technique was used to determine cell viability. Results At the three exposure times, cell survival progressively decreased with increasing concentration, but the effect of either chemical was not significant (ANOVA; P -5 M when either chemical was applied for 16 or 28 h. Furthermore, the mean SCE increased with longer exposure times and, in general, CSe had slightly greater effect on cell survival and caused higher frequencies of SCE than CS. The exception was the 10-8 M treatment. However, both CSe and CS failed to induce 2-fold SCE as that of the negative control and therefore they are not considered as mutagens. Conclusion Both CSe and CS in the range of 10-8 to 10-5 M could not double the SCE rate of the negative control and therefore not considered as mutagens at these experimental conditions.

  12. Do the organic sulfur compounds DMSP and DMS drive coral microbial associations?

    Science.gov (United States)

    Raina, Jean-Baptiste; Dinsdale, Elizabeth A; Willis, Bette L; Bourne, David G

    2010-03-01

    Dimethylsulfoniopropionate (DMSP) and dimethylsulfide (DMS) are key compounds in the global sulfur cycle. Moreover, DMS is particularly important in climate regulation owing to its role in cloud formation. Reef building corals are major contributors to the production of these two compounds and also form diverse and complex associations with bacteria, which are known to play a crucial role in the degradation of DMSP and DMS. Here, we highlight an extensive overlap between bacterial species implicated in DMSP/DMS degradation and those associated with corals, leading to the hypothesis that these two compounds play a major role in structuring coral-associated bacterial communities, with important consequences for coral health and the resilience of coral reefs. We also explore the publically available metagenome databases and show that genes implicated in DMSP metabolism are abundant in the viral component of coral-reef-derived metagenomes, indicating that viruses can act as a reservoir for such genes.

  13. Detection and classification of gaseous sulfur compounds by solid electrolyte cyclic voltammetry of cermet sensor array.

    Science.gov (United States)

    Kramer, Kirsten E; Rose-Pehrsson, Susan L; Hammond, Mark H; Tillett, Duane; Streckert, Holger H

    2007-02-12

    Electrochemical sensors composed of a ceramic-metallic (cermet) solid electrolyte are used for the detection of gaseous sulfur compounds SO(2), H(2)S, and CS(2) in a study involving 11 toxic industrial chemical (TIC) compounds. The study examines a sensor array containing four cermet sensors varying in electrode-electrolyte composition, designed to offer selectivity for multiple compounds. The sensors are driven by cyclic voltammetry to produce a current-voltage profile for each analyte. Raw voltammograms are processed by background subtraction of clean air, and the four sensor signals are concatenated to form one vector of points. The high-resolution signal is compressed by wavelet transformation and a probabilistic neural network is used for classification. In this study, training data from one sensor array was used to formulate models which were validated with data from a second sensor array. Of the 11 gases studied, 3 that contained sulfur produced the strongest responses and were successfully analyzed when the remaining compounds were treated as interferents. Analytes were measured from 10 to 200% of their threshold-limited value (TLV) according to the 8-h time weighted average (TWA) exposure limits defined by the National Institute of Occupational Safety and Health (NIOSH). True positive classification rates of 93.3, 96.7, and 76.7% for SO(2), H(2)S, and CS(2), respectively, were achieved for prediction of one sensor unit when a second sensor was used for modeling. True positive rates of 83.3, 90.0, and 90.0% for SO(2), H(2)S, and CS(2), respectively, were achieved for the second sensor unit when the first sensor unit was used for modeling. Most of the misclassifications were for low concentration levels (such 10-25% TLV) in which case the compound was classified as clean air. Between the two sensors, the false positive rates were 2.2% or lower for the three sulfur compounds, 0.9% or lower for the interferents (eight remaining analytes), and 5.8% or lower for

  14. Detection and classification of gaseous sulfur compounds by solid electrolyte cyclic voltammetry of cermet sensor array

    International Nuclear Information System (INIS)

    Kramer, Kirsten E.; Rose-Pehrsson, Susan L.; Hammond, Mark H.; Tillett, Duane; Streckert, Holger H.

    2007-01-01

    Electrochemical sensors composed of a ceramic-metallic (cermet) solid electrolyte are used for the detection of gaseous sulfur compounds SO 2 , H 2 S, and CS 2 in a study involving 11 toxic industrial chemical (TIC) compounds. The study examines a sensor array containing four cermet sensors varying in electrode-electrolyte composition, designed to offer selectivity for multiple compounds. The sensors are driven by cyclic voltammetry to produce a current-voltage profile for each analyte. Raw voltammograms are processed by background subtraction of clean air, and the four sensor signals are concatenated to form one vector of points. The high-resolution signal is compressed by wavelet transformation and a probabilistic neural network is used for classification. In this study, training data from one sensor array was used to formulate models which were validated with data from a second sensor array. Of the 11 gases studied, 3 that contained sulfur produced the strongest responses and were successfully analyzed when the remaining compounds were treated as interferents. Analytes were measured from 10 to 200% of their threshold-limited value (TLV) according to the 8-h time weighted average (TWA) exposure limits defined by the National Institute of Occupational Safety and Health (NIOSH). True positive classification rates of 93.3, 96.7, and 76.7% for SO 2 , H 2 S, and CS 2 , respectively, were achieved for prediction of one sensor unit when a second sensor was used for modeling. True positive rates of 83.3, 90.0, and 90.0% for SO 2 , H 2 S, and CS 2 , respectively, were achieved for the second sensor unit when the first sensor unit was used for modeling. Most of the misclassifications were for low concentration levels (such 10-25% TLV) in which case the compound was classified as clean air. Between the two sensors, the false positive rates were 2.2% or lower for the three sulfur compounds, 0.9% or lower for the interferents (eight remaining analytes), and 5.8% or lower for

  15. Kinetics of aerobic oxidation of volatile sulfur compounds in wastewater and biofilm from sewers

    DEFF Research Database (Denmark)

    Rudelle, Elise Alice; Vollertsen, Jes; Hvitved-Jacobsen, Thorkild

    2013-01-01

    Laboratory experiments were conducted to investigate the kinetics of aerobic chemical and biological oxidation of selected odorous volatile sulfur compounds (VSCs) by wastewater and biofilm from sewers. The VSCs included methyl mercaptan (MeSH), ethyl mercaptan (EtSH), dimethyl sulfide (DMS......-spot downstream of a force main and the other was a gravity sewer transporting young aerobic wastewater. The kinetics of VSC oxidation for both wastewater and suspended biofilm samples followed a first-order rate equation. The average values of the reaction rate constants demonstrated the following order...... in the aerobic wastewater....

  16. Sulfurized limonite as material for fast decomposition of organic compounds by heterogeneous Fenton reaction

    International Nuclear Information System (INIS)

    Toda, Kei; Tanaka, Toshinori; Tsuda, Yutaka; Ban, Masahiro; Koveke, Edwin P.; Koinuma, Michio; Ohira, Shin-Ichi

    2014-01-01

    Graphical abstract: - Highlights: • Used limonite degrades organic compounds by heterogeneous Fenton reaction. • Sulfurized limonite removes methylene blue color in seconds. • Recycled limonite can be used for biogas purification and wastewater treatment. - Abstract: Rapid decomposition of wastewater contaminants using sulfurized limonite (S-limonite) was investigated. Limonite is used for desulfurization of biogases, and S-limonite is obtained from desulfurization plants as solid waste. In this work, the profitable use of S-limonite in water treatment was examined. The divalent Fe in S-limonite was expected to produce OH radicals, as Fe 2+ ions and limonite thermally treated with H 2 do. Methylene blue was used for batch-wise monitoring of the decomposition performance. The decomposition rate was fast and the methylene blue solution color disappeared in only 10 s when a small amount of H 2 O 2 was added (1 mM in the sample solution) in the presence of S-limonite. The OH radicals were formed by a heterogeneous reaction on the S-limonite surface and Fenton reaction with dissolved Fe 2+ . The decomposition of pentachlorophenol was also examined; it was successfully decomposed in batch-wise tests. The surfaces of limonite before sulfurization, S-limonite, and S-limonite after use for water treatment were performed using scanning electron microscopy and X-ray photoelectron spectroscopy. The results show that S-limonite reverted to limonite after being used for water treatment

  17. Sulfurized limonite as material for fast decomposition of organic compounds by heterogeneous Fenton reaction

    Energy Technology Data Exchange (ETDEWEB)

    Toda, Kei, E-mail: todakei@sci.kumamoto-u.ac.jp [Department of Chemistry, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan); Tanaka, Toshinori; Tsuda, Yutaka; Ban, Masahiro; Koveke, Edwin P. [Department of Chemistry, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan); Koinuma, Michio [Department of Chemistry and Biochemistry, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan); Ohira, Shin-Ichi [Department of Chemistry, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan)

    2014-08-15

    Graphical abstract: - Highlights: • Used limonite degrades organic compounds by heterogeneous Fenton reaction. • Sulfurized limonite removes methylene blue color in seconds. • Recycled limonite can be used for biogas purification and wastewater treatment. - Abstract: Rapid decomposition of wastewater contaminants using sulfurized limonite (S-limonite) was investigated. Limonite is used for desulfurization of biogases, and S-limonite is obtained from desulfurization plants as solid waste. In this work, the profitable use of S-limonite in water treatment was examined. The divalent Fe in S-limonite was expected to produce OH radicals, as Fe{sup 2+} ions and limonite thermally treated with H{sub 2} do. Methylene blue was used for batch-wise monitoring of the decomposition performance. The decomposition rate was fast and the methylene blue solution color disappeared in only 10 s when a small amount of H{sub 2}O{sub 2} was added (1 mM in the sample solution) in the presence of S-limonite. The OH radicals were formed by a heterogeneous reaction on the S-limonite surface and Fenton reaction with dissolved Fe{sup 2+}. The decomposition of pentachlorophenol was also examined; it was successfully decomposed in batch-wise tests. The surfaces of limonite before sulfurization, S-limonite, and S-limonite after use for water treatment were performed using scanning electron microscopy and X-ray photoelectron spectroscopy. The results show that S-limonite reverted to limonite after being used for water treatment.

  18. Biodegradation tests of mercaptocarboxylic acids, their esters, related divalent sulfur compounds and mercaptans.

    Science.gov (United States)

    Rücker, Christoph; Mahmoud, Waleed M M; Schwartz, Dirk; Kümmerer, Klaus

    2018-04-17

    Mercaptocarboxylic acids and their esters, a class of difunctional compounds bearing both a mercapto and a carboxylic acid or ester functional group, are industrial chemicals of potential environmental concern. Biodegradation of such compounds was systematically investigated here, both by literature search and by experiments (Closed Bottle Test OECD 301D and Manometric Respirometry Test OECD 301F). These compounds were found either readily biodegradable or at least biodegradable to a significant extent. Some related compounds of divalent sulfur were tested for comparison (mercaptans, sulfides, disulfides). For the two relevant monofunctional compound classes, carboxylic acids/esters and mercaptans, literature data were compiled, and by comparison with structurally similar compounds without these functional groups, the influence of COOH/COOR' and SH groups on biodegradability was evaluated. Thereby, an existing rule of thumb for biodegradation of carboxylic acids/esters was supported by experimental data, and a rule of thumb could be formulated for mercaptans. Concurrent to biodegradation, abiotic processes were observed in the experiments, rapid oxidative formation of disulfides (dimerisation of monomercaptans and cyclisation of dimercaptans) and hydrolysis of esters. Some problems that compromise the reproducibility of biodegradation test results were discussed.

  19. Identification of a New Antibacterial Sulfur Compound from Raphanus sativus Seeds

    Directory of Open Access Journals (Sweden)

    Jeries Jadoun

    2016-01-01

    Full Text Available Raphanus sativus L. (radish, a member of Brassicaceae, is widely used in traditional medicine in various cultures for treatment of several diseases and disorders associated with microbial infections. The antibacterial activity of the different plant parts has been mainly attributed to several isothiocyanate (ITC compounds. However, the low correlation between the ITC content and antibacterial activity suggests the involvement of other unknown compounds. The objective of this study was to investigate the antibacterial potential of red radish seeds and identify the active compounds. A crude ethanol seed extract was prepared and its antibacterial activity was tested against five medically important bacteria. The ethanol extract significantly inhibited the growth of all tested strains. However, the inhibitory effect was more pronounced against Streptococcus pyogenes and Escherichia coli. Bioassay-guided fractionation of the ethanol extract followed by HPLC, 1H-NMR, 13C-NMR, 15N-NMR, and HMBC analysis revealed that the active fraction consisted of a single new compound identified as [5-methylsulfinyl-1-(4-methylsulfinyl-but-3-enyl-pent-4-enylidene]-sulfamic acid, which consisted of two identical sulfur side chains similar to those found in ITCs. The minimal inhibitory concentration values of the isolated compound were in the range of 0.5–1 mg/mL. These results further highlight the role of radish as a rich source of antibacterial compounds.

  20. Information profiles on potential occupational hazards: Inorganic chromium compounds. Draft report (Second)

    Energy Technology Data Exchange (ETDEWEB)

    1982-02-01

    Information profiles are presented for the following inorganic chromium compounds: chromic(VI) acid, chromic(III) hydroxide, chromic(III) oxide, chromic(III) sulfate, chromic(III) sulfate (basic), chromium dioxide, potassium dichromate(VI), lead chromate, sodium-chromate(VI), sodium-dichromate(VI), and zinc-yellow-chromate(VI). Biological effects of hexavalent chromium in humans included skin ulceration, dermatitis, nasal membrane irritation and ulceration, nasal septal perforation, rhinitis, nosebleed, nephritis, liver damage, epigastric pain, pulmonary congestion and edema, and erosion and discoloration of teeth. Chromium(VI) compounds caused mutations in a variety of systems. Exposure to trivalent chromium in the work place has caused contact dermatitis and chrome ulcers. Epidemiological studies indicated respiratory carcinogenicity among workers occupationally exposed during chromate production.

  1. A method for eliminating sulfur compounds from fluid, saturated, aliphatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Fakhriev, A.M.; Galiautdinov, N.G.; Kashevarov, L.A.; Mazgarov, A.M.

    1982-01-01

    The method for eliminating sulfur compounds from fluid, saturated, aliphatic hydrocarbons, which involves extracting hydrocarbons using a dimethylsulfoxide extractant, is improved by using a dimethylsulfoxide blend and 10-60 percent (by volume) diethylenetriamine or polyethylenepolyamine which contains diethylenetriamine, triethylenetetramine and tetraethylenepentamine, in order to eliminate the above compounds. Polyethylenepolyamine is produced as a by-product during the production of ethylenediamine. Elimination is performed at 0-50 degrees and 1-60 atmospheres of pressure. Here, the extractant may contain up to 10 percent water. The use of the proposed method, rather than the existing method, will make it possible to increase hydrocarbon elimination from mercaptans by 40 percent and from H/sub 2/S by 10 percent when the same amount is eliminated from dialkylsulfides.

  2. Spectral determination of individual rare earths in different classes of inorganic compounds

    International Nuclear Information System (INIS)

    Karpenko, L.I.; Fadeeva, L.A.; Shevchenko, L.D.

    1979-01-01

    The conditions are found allowing to analyze various inorganic compounds for rare-earth elements without separation from non-rare-earth components. The influence of the plasma composition on the intensity of spectral lines of rare-earth elements is studied. The relative intensity of homologous spectral lines of various rare-earth elements remains constant regardless of the plasma composition. The conditions are found for the determination of individual rare-earth elements acting as both alloying additives (Csub(n) -- n x 10 -1 -n x 10 -3 %), and basic components (up to tens of per cent) in different classes of inorganic compounds of 1-7 elements. The general method is developed for the determination of individual rare-earth elements in mixtures of oxides of rare-earth elements, complex fluorides of rare-earth elements and elements of group 2, gallates, borates, germanates, vanadates of rare-earth elements and aluminium; zirconates-titanates of lead and barium, containing modifying additives of rare-earth elements, complex chalcogenides of rare-earth elements and elements of group 5

  3. Removal of sulfur compounds from diesel using ArF laser and oxygen.

    Science.gov (United States)

    Gondal, M A; Siddiqui, M N; Al-Hooshani, K

    2013-01-01

    A laser-based technique for deep desulfurization of diesel and other hydrocarbon fuels by removal of dimethyldibenzothiophene (DMDBT), a persistent sulfur contaminant in fuel oils has been developed. We report a selective laser excitation of DMDBT in diesel and model compounds such as n-hexane in a reaction chamber under oxygen environment where oxidative reactions can take place. ArF laser emitting at 193 nm was employed for excitation of oxygen and DMDBT, while for process optimization, the laser energy was varied from 50 to 200 mJ/cm(2). The laser-irradiated DMDBT solution under continuous oxygen flow was analyzed by UV absorption spectrometer to determine the photochemical oxidative degradation of DMDBT. In just 5 min of laser irradiation time, almost 95% DMDBT was depleted in a diesel containing 200 ppm of DMDBT. This article provides a new method for the removal of sulfur compounds from diesel by laser based photochemical process.

  4. Reactivity of silicon and germanium doped CNTs toward aromatic sulfur compounds: A theoretical approach

    International Nuclear Information System (INIS)

    Galano, Annia; Francisco-Marquez, Misaela

    2008-01-01

    Adsorption processes of thiophene and benzothiophene on pristine carbon nanotubes (CNTs), and on CNTs doped with Si or Ge, have been modeled with Density Functional. This is the first study on the chemical reactivity of such doped tubes. The calculated data suggest that the presence of silicon or germanium atoms in CNTs increases their reactivity toward thiophene, and benzothiophene. The adsorption of these species on pristine CNTs seems very unlikely to occur, while the addition products involving doped CNTs were found to be very stable, with respect to the isolated reactants, in terms of Gibbs free energy. Several of these adsorption processes were found to be significantly exergonic (ΔG < 0) in non-polar liquid phase. The results reported in this work suggest that Si and Ge defects on CNTs increase their reactivity toward unsaturated species, and could make them useful in the removal processes of aromatic sulfur compounds from oil-hydrocarbons. However, according to our results, CNTs doped with Si atoms are expected to be more efficient as aromatic sulfur compounds scavengers than those doped with Ge. These results also suggest that the presence of silicon and germanium atoms in the CNTs structures enhances their reactivity toward nucleophilic molecules, compared to pristine carbon nanotubes

  5. Emission of volatile sulfur compounds during composting of municipal solid waste (MSW)

    International Nuclear Information System (INIS)

    Zhang, Hongyu; Schuchardt, Frank; Li, Guoxue; Yang, Jinbing; Yang, Qingyuan

    2013-01-01

    Highlights: ► We compare the volatile sulfur compounds (VSCs) emissions during three types of municipal solid wastes (MSWs) composting. ► The VSCs released from the kitchen waste composting was significantly higher than that from 15–80 mm fraction of MSW. ► Among the five VSCs, H 2 S was the most abundant compound with 39.0–43.0% of total VSCs released. ► Addition of 20% cornstalks could significantly reduce the VSCs emissions during kitchen waste composting. - Abstract: Volatile sulfur compounds (VSCs) are the main source for malodor from composting plants. In this study, the VSCs generated from composting of 15–80 mm municipal solid waste (T0), kitchen waste (T1) and kitchen waste mixed dry cornstalks (T2) were measured in 60 L reactors with forced aeration for a period of 30 days. The VSCs detected in all treatments were hydrogen sulfide (H 2 S), methyl mercaptan (MM), dimethyl sulfide (DMS), carbon bisulfide (CS 2 ) and dimethyl disulfide (DMDS). Over 90% of the VSCs emissions occurred during the first 15 days, and reached their peak values at days 4–7. The emission profiles of five VSCs species were significantly correlated with internal materials temperature and outlet O 2 concentration (p −1 (dry matter) for T0, T1 and T2, respectively. Among the five VSCs, H 2 S was the most abundant compound with 39.0–43.0% of total VSCs released. Composting of kitchen waste from separate collection posed a negative influence on the VSC and leachate production because of its high moisture content. An addition of dry cornstalks at a mixing ratio of 4:1 (wet weight) could significantly reduce the VSCs emissions and avoid leachate. Compared to pure kitchen waste, VSCs were reduced 66.8%

  6. Sulfur metabolism in the extreme acidophile Acidithiobacillus caldus

    Directory of Open Access Journals (Sweden)

    Stefanie eMangold

    2011-02-01

    Full Text Available Given the challenges to life at low pH, an analysis of inorganic sulfur compound oxidation was initiated in the chemolithoautotrophic extremophile Acidithiobacillus caldus. A. caldus is able to metabolize elemental sulfur and a broad range of inorganic sulfur compounds. It has been implicated in the production of environmentally damaging acidic solutions as well as participating in industrial bioleaching operations where it forms part of microbial consortia used for the recovery of metal ions. Based upon the recently published A. caldus type strain genome sequence, a bioinformatic reconstruction of elemental sulfur and inorganic sulfur compound metabolism predicted genes included: sulfide quinone reductase (sqr, tetrathionate hydrolase (tth, two sox gene clusters potentially involved in thiosulfate oxidation (soxABXYZ, sulfur oxygenase reductase (sor, and various electron transport components. RNA transcript profiles by semi-quantitative reverse transcription PCR suggested up-regulation of sox genes in the presence of tetrathionate. Extensive gel based proteomic comparisons of total soluble and membrane enriched protein fractions during growth on elemental sulfur and tetrathionate identified differential protein levels from the two Sox clusters as well as several chaperone and stress proteins up-regulated in the presence of elemental sulfur. Proteomics results also suggested the involvement of heterodisulfide reductase (HdrABC in A. caldus inorganic sulfur compound metabolism. A putative new function of Hdr in acidophiles is discussed. Additional proteomic analysis evaluated protein expression differences between cells grown attached to solid, elemental sulfur versus planktonic cells. This study has provided insights into sulfur metabolism of this acidophilic chemolithotroph and gene expression during attachment to solid elemental sulfur.

  7. Synthesis and characterization of porous metal oxides and desulfurization studies of sulfur containing compounds

    Science.gov (United States)

    Garces Trujillo, Hector Fabian

    This thesis contains two parts: 1) synthesis and characterization of porous metal oxides that include zinc oxide and a porous mixed-valent manganese oxide with an amorphous structure (AMO) 2) the desulfurization studies for the removal of sulfur compounds. Zinc oxide with different nano-scale morphologies may result in various porosities with different adsorption capabilities. A tunable shape microwave synthesis of ZnO nano-spheres in a co-solvent mixture is presented. The ZnO nano-sphere material is investigated as a desulfurizing sorbent in a fixed bed reactor in the temperature range 200 to 400 °C and compared with ZnO nanorods and platelet-like morphologies. Fresh and sulfided materials were characterized by X-ray diffraction (XRD), BET specific surface area, pore volume, scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (SEM/EDX), Raman spectroscopy, and thermogravimetric analysis (TGA). The tunable shape microwave synthesis of ZnO presents a high sulfur sorption capacity at temperatures as low as 200 °C which accounts for a three and four fold enhancement over the other preparations presented in this work, and reached 76 % of the theoretical sulfur capacity (TSC) at 300 °C. Another ZnO material with a bimodal micro- and mesopore size distribution investigated as a desulfurizing sorbent presents a sorption capacity that reaches 87% of the theoretical value for desulfurization at 400 °C at breakthrough time. A deactivation model that considers the activity of the solid reactant was used to fit the experimental data. Good agreement between the experimental breakthrough curves and the model predictions are obtained. Manganese oxides are a type of metal oxide materials commonly used in catalytic applications. Little is known about the adsorption capabilities for the removal of sulfur compounds. One of these manganese oxides; amorphous manganese oxide (AMO) is highly promising material for low temperature sorption processes. Amorphous

  8. Apparent Disequilibrium of Inorganic and Organic Carbon Compounds in Serpentinizing Fluids

    Science.gov (United States)

    Robinson, K.; Shock, E.

    2014-12-01

    During serpentinization of ultramafic rocks, ferrous iron in silicates is oxidized to ferric minerals and H2O is reduced to H2. This process is accompanied by the reduction of inorganic carbon, as observed in experiments and natural systems. To test the extent to which stable and metastable equilibria are reached among aqueous organic compounds during serpentinization, we sampled water and dissolved gases from circumneutral surface pools and hyperalkaline seeps in the Samail ophiolite in the Sultanate of Oman and analyzed for various carbon constituents, including dissolved inorganic carbon, dissolved organic carbon, methane, carbon monoxide, formate, acetate, and other small organic acid anions. Measurements of temperature, pH, dissolved H2, O2, major cations, major anions, and major and trace elements were also made. The aqueous composition of the analyzed samples was speciated based on ionic equilibrium interactions in order to obtain activities for inorganic carbon species, reduced carbon species, H2, and O2. The redox disequilibria among carbon species was then assessed using data and parameters for the revised HKF equations of state. This analysis demonstrates that the carbon species in this system are out of equilibrium with respect to one another in ways that cannot be compensated by altering the abundance of the other constituents within analytical uncertainties. Specifically, there is too much formate and too little methane relative to stable and metastable equilibria. This result implies the following: 1) Methane and formate equilibrated in separate parts of the system, given that no reasonable temperature, pressure, or composition changes satisfy equilibrium with their measured abundances. 2) Methane production is kinetically inhibited, as seen in experiments. 3) Microbial methane oxidation altered the abundance of methane and formate; methane oxidation to formate or carbonate is calculated to be extremely thermodynamically favorable in these fluids.

  9. Possibility of use of Azgir underground nuclear cavities for burial of sulfur and her toxic compounds - products of oil refining

    International Nuclear Information System (INIS)

    Akhmetov, E.Z.; Adymov, Zh.I.

    1998-01-01

    The intensive growth of production oil and gas in Western Kazakhstan increases ecological vulnerability of an environment and a fauna because of the pressure of negative consequences arising with production, refining and transportation of the oil raw material, and also because of pernicious influence of accompanying products and wastes of oil refining manufacture being chemically dangerous and toxic, requiring special conditions of the handling, warehousing and storage for provision of ecological safety. A problem of the reclamation, safe warehousing, storage and long-term disposal (burial) of such accompanying products and wastes, as for example, sulfur and its compounds till now is not solved. For example, the mass of the accumulated mountains of crystal sulfur makes on cautious calculations from 2 up to 3 million tonnes also creates real danger of the propagation and harmful influence on the environment. The neutralization of sulfur and its compounds means removal them from the active handling with an environment, i.e. creation of such conditions in which sulfur products for a long time cannot cause harm atmosphere, underground medium and waters, vegetative and animal world. For it is offered to use underground cavities in a salt dome raising Large Azgir and the funnel-shaped hollow in persalt rocks formed as a result of underground nuclear explosions, carried out in 1978-1979 years near village Azgir Atyrau province. The sulfur products is possible to place on a long safe storage in funnel-shaped hollow (the A9 platform) volume 1,5 million cubic meters, by keeping, if necessary, an possibility of their extraction for needs of the future generations or to remove in underground nuclear cavities in stone salt (the A8 and A11 platforms) total volume 330000 cubic meters, from which it is not provided in the future to take out the sulfur products. At this the sulfur is removed from an environment on a storage or burial in the inactive form, i.e. the sulfur products

  10. Manganese-Loaded Activated Carbon for the Removal of Organosulfur Compounds from High-Sulfur Diesel Fuels

    OpenAIRE

    Al-Ghouti, M.A.; Al-Degs, Y.S.

    2014-01-01

    The adsorptive capacity of activated carbon (AC) is significantly enhanced toward weakly interacting organosulfur compounds (OSC) from sulfur-rich diesel fuel. Sulfur compounds are selectively removed from diesel after surface modification by manganese dioxide (MnO2). A selective surface for OSC removal was created by loading MnO2 on the surface; π-complexation between the partially filled d-orbitals of Mn4+ and the S atom is the controlling mechanism for OSC removal. Principal component anal...

  11. Migration of residual nonvolatile and inorganic compounds from recycled post-consumer PET and HDPE

    Energy Technology Data Exchange (ETDEWEB)

    Dutra, Camila; Reyes, Felix G.R., E-mail: reyesfgr@fea.unicamp.br [Universidade de Campinas (UNICAMP), SP (Brazil). Escola de Engenharia dos Alimentos. Dept. de Ciencias dos Alimentos; Freire, Maria Teresa de A. [Universidade de Sao Paulo (USP), Pirassununga, SP (Brazil). Fac. de Ciencia Animal e Engenharia dos Alimentos. Dept. de Engenharia dos Alimentos; Nerin, Cristina; Bentayeb, Karim; Rodriguez-Lafuente, Angel; Aznar, Margarita [Dept. of Analytical Chemistry, Arago Inst. of Engineering Research, University of Zaragoza (Spain)

    2014-04-15

    Migration of nonvolatile and inorganic residual compounds from post-consumer recycled polyethylene terephthalate (PET) submitted to cleaning processes for subsequent production of materials intended to food contact, as well as from multilayer packaging material containing post-consumer recycled high-density polyethylene (HDPE) was determined. Tests were carried out using food simulant. Nonvolatile organic contaminants from PET, determined by liquid chromatography-mass spectrometry (UPLC-QqQ/MS), showed significant migration reduction as consequence of the more complex cleaning technologies applied. However, contaminants not allowed by Brazilian and European Union regulations were identified even in deep cleaning samples. Results from multilayer HDPE showed a greater number of contaminants when compared to recycled pellets. Inorganic contaminants, determined by inductively coupled plasma mass spectrometry were below the acceptable levels. Additional studies for identification and quantitation of unknown molecules which were not possible to identify in this study by UPLC-QqQ/MS are required to ascertain the safety of using post-consumer recycled packaging material. (author)

  12. Enhancing Optically Pumped Organic-Inorganic Hybrid Perovskite Amplified Spontaneous Emission via Compound Surface Plasmon Resonance

    Directory of Open Access Journals (Sweden)

    Xiaoyan Wu

    2018-03-01

    Full Text Available Organic-inorganic hybrid perovskite has attracted intensive attention from researchers as the gain medium in lasing devices. However, achieving electrically driven lasing remains a significant challenge. Modifying the devices’ structure to enhance the optically pumped amplified spontaneous emission (ASE is the key issue. In this work, gold nanoparticles (Au NPs are first doped into PEDOT: PSS buffer layer in a slab waveguide device structure: Quartz/PEDOT: PSS (with or w/o Au NPs/CH3NH3PbBr3. As a result, the facile device shows a significantly enhanced ASE intensity and a narrowed full width at half maximum. Based on experiments and theoretical simulation data, the improvement is mainly a result of the compound surface plasmon resonance, including simultaneous near- and far-field effects, both of which could increase the density of excitons excited state and accelerate the radiative decay process. This method is highly significant for the design and development and fabrication of high-performance organic-inorganic hybrid perovskite lasing diodes.

  13. Is climate influenced by biogenic atmospheric sulfur compounds. Beeinflussen biogene atmosphaerische Schwefelverbindungen das Klima

    Energy Technology Data Exchange (ETDEWEB)

    Georgii, H W

    1990-01-01

    About 10 years ago, traces of gaseous sulfur compounds were detected in the atmosphere which are of mainly biogenic origin and are formed in large areas in the oceans by phytoplankton. Continental sources, too, are important. These gases - dimethyl sulfide, carbon bisulfide and carbonyl sulfide - provide an important, if not the main, part to the natural sulfur budget of the atmosphere. While dimethyl sulfide and carbon bisulfide are quickly oxidized in the lower atmosphere forming sulfate particles in the process, carbonyl sulfide is an inert gas which is oxidized only after reaching the stratosphere. Lately, the relevance of these trace components to climate is being discussed. Conceivably, they might influence the radiation budget of the earth via the formation of aerosol particles: While, in the case of dimethyl sulfide, these would change the microphysical parameters of maritime clouds, an increase in the production of carbonyl sulfide would entail a strengthening of the stratospheric sulfate particle layer. Both processes might have a stabilizing effect on the climate as they act in opposite direction to the much discussed greenhouse effect. (orig.).

  14. Evolutions of volatile sulfur compounds of Cabernet Sauvignon wines during aging in different oak barrels.

    Science.gov (United States)

    Ye, Dong-Qing; Zheng, Xiao-Tian; Xu, Xiao-Qing; Wang, Yun-He; Duan, Chang-Qing; Liu, Yan-Lin

    2016-07-01

    The evolution of volatile sulfur compounds (VSCs) in Cabernet Sauvignon wines from seven regions of China during maturation in oak barrels was investigated. The barrels were made of different wood grains (fine and medium) and toasting levels (light and medium). Twelve VSCs were quantified by GC/FPD, with dimethyl sulfide (DMS) and methionol exceeding their sensory thresholds. Most VSCs tended to decline during the aging, while DMS was found to increase. After one year aging, the levels of DMS, 2-methyltetrahy-drothiophen-3-one and sulfur-containing esters were lower in the wines aged in oak barrels than in stainless steel tanks. The wood grain and toasting level of oak barrels significantly influenced the concentration of S-methyl thioacetate and 2-methyltetrahy-drothiophen-3-one. This study reported the evolution of VSCs in wines during oak barrel aging for the first time and evaluated the influence of barrel types, which would provide wine-makers with references in making proposals about wine aging. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Direct night-time ejection of particle-phase reduced biogenic sulfur compounds from the ocean to the atmosphere.

    Science.gov (United States)

    Gaston, Cassandra J; Furutani, Hiroshi; Guazzotti, Sergio A; Coffee, Keith R; Jung, Jinyoung; Uematsu, Mitsuo; Prather, Kimberly A

    2015-04-21

    The influence of oceanic biological activity on sea spray aerosol composition, clouds, and climate remains poorly understood. The emission of organic material and gaseous dimethyl sulfide (DMS) from the ocean represents well-documented biogenic processes that influence particle chemistry in marine environments. However, the direct emission of particle-phase biogenic sulfur from the ocean remains largely unexplored. Here we present measurements of ocean-derived particles containing reduced sulfur, detected as elemental sulfur ions (e.g., (32)S(+), (64)S2(+)), in seven different marine environments using real-time, single particle mass spectrometry; these particles have not been detected outside of the marine environment. These reduced sulfur compounds were associated with primary marine particle types and wind speeds typically between 5 and 10 m/s suggesting that these particles themselves are a primary emission. In studies with measurements of seawater properties, chlorophyll-a and atmospheric DMS concentrations were typically elevated in these same locations suggesting a biogenic source for these sulfur-containing particles. Interestingly, these sulfur-containing particles only appeared at night, likely due to rapid photochemical destruction during the daytime, and comprised up to ∼67% of the aerosol number fraction, particularly in the supermicrometer size range. These sulfur-containing particles were detected along the California coast, across the Pacific Ocean, and in the southern Indian Ocean suggesting that these particles represent a globally significant biogenic contribution to the marine aerosol burden.

  16. Controlling the release of active compounds from the inorganic carrier halloysite

    International Nuclear Information System (INIS)

    Tescione, F.; Buonocore, G. G.; Stanzione, M.; Oliviero, M.; Lavorgna, M.

    2014-01-01

    Halloysite (HNTs), a natural material characterized by a nanotube structure, has been used as an inorganic carrier of active compounds in several applications from medicine to anticorrosion coatings. In this present work, vanillin (VAN) used as a antimicrobial model, has been encapsulated within HNTs for exploiting its applicability in the active food packaging sector. The molecule release rate has been controlled by crosslinking at the tube ends the loaded vanillin with copper ions, thus producing a stopper network. The vanillin-loaded HNTs were characterized using transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy and thermo gravimetric analysis. The antimicrobial release kinetics from the loaded nanoparticles (VAN/HNTs) in water was investigated using UV-vis spectroscopy. The results show that the vanillin crosslinked with cupper ions is a feasible method to tailor the release rate of antimicrobial model from HTNs nanoparticles

  17. Controlling the release of active compounds from the inorganic carrier halloysite

    Energy Technology Data Exchange (ETDEWEB)

    Tescione, F.; Buonocore, G. G.; Stanzione, M.; Oliviero, M.; Lavorgna, M. [National Research Council - Institute of Composites and Biomedical Materials, P.le E. Fermi, 1 80055 Portici (Naples) (Italy)

    2014-05-15

    Halloysite (HNTs), a natural material characterized by a nanotube structure, has been used as an inorganic carrier of active compounds in several applications from medicine to anticorrosion coatings. In this present work, vanillin (VAN) used as a antimicrobial model, has been encapsulated within HNTs for exploiting its applicability in the active food packaging sector. The molecule release rate has been controlled by crosslinking at the tube ends the loaded vanillin with copper ions, thus producing a stopper network. The vanillin-loaded HNTs were characterized using transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy and thermo gravimetric analysis. The antimicrobial release kinetics from the loaded nanoparticles (VAN/HNTs) in water was investigated using UV-vis spectroscopy. The results show that the vanillin crosslinked with cupper ions is a feasible method to tailor the release rate of antimicrobial model from HTNs nanoparticles.

  18. Bonding in inorganic compounds: a study by x-ray photoelectron spectroscopy

    International Nuclear Information System (INIS)

    Avanzino, S.C.

    1978-10-01

    Core electron binding energies were measured for a variety of inorganic and organometallic compounds using gas-phase X-ray photoelectron spectroscopy (XPS). The atomic charge distributions in these molecules are deduced from the binding energies, often leading to a better understanding of the bonding in these compounds. The XPS spectra of fifteen volatile tin compounds were recorded. The data suggest that the metal d orbitals are not significantly involved in the bonding. The oxygen ls XPS spectra of gaseous CH 3 Mn(CO) 5 , [π-C 5 H 5 Fe(CO) 2 ] 2 , and Co 4 (CO) 12 can be readily resolved into separate peaks due to bridging and terminal carbonyl groups. The C ls spectrum of Fe(CO) 5 consists of a single symmetric peak. The carbonyl ligand core binding energies of transition-metal carbonyl complexes are sensitive to differences in the metal-to-CO ligand bonding. Both C ls and O ls carbonyl binding energies correlate well with average C-O stretching force constants or average C-O stretching frequencies. The metal and carbonyl binding energies in a series of pentacarbonylmanganese complexes LMn(CO) 5 are a good measure of the relative electronegativities of the ligands L. High-quality X-ray photoelectron spectra have been obtained for compounds dissolved in glycerin solutions, and aqueous solutions were converted into glycerin solutions which gave good XRSspectra of the solutes. The technique appears promising as a future analytical application of X-ray photoelectron spectroscopy. The shifts in the binding energies of oxygen, chlorine, and carbon atoms in some isoelectronic isostructural compounds can be explained in terms of simple trends in atomic charges

  19. Malodorous volatile organic sulfur compounds: Sources, sinks and significance in inland waters.

    Science.gov (United States)

    Watson, Susan B; Jüttner, Friedrich

    2017-03-01

    Volatile Organic Sulfur Compounds (VOSCs) are instrumental in global S-cycling and greenhouse gas production. VOSCs occur across a diversity of inland waters, and with widespread eutrophication and climate change, are increasingly linked with malodours in organic-rich waterbodies and drinking-water supplies. Compared with marine systems, the role of VOSCs in biogeochemical processes is far less well characterized for inland waters, and often involves different physicochemical and biological processes. This review provides an updated synthesis of VOSCs in inland waters, focusing on compounds known to cause malodours. We examine the major limnological and biochemical processes involved in the formation and degradation of alkylthiols, dialkylsulfides, dialkylpolysulfides, and other organosulfur compounds under different oxygen, salinity and mixing regimes, and key phototropic and heterotrophic microbial producers and degraders (bacteria, cyanobacteria, and algae) in these environs. The data show VOSC levels which vary significantly, sometimes far exceeding human odor thresholds, generated by a diversity of biota, biochemical pathways, enzymes and precursors. We also draw attention to major issues in sampling and analytical artifacts which bias and preclude comparisons among studies, and highlight significant knowledge gaps that need addressing with careful, appropriate methods to provide a more robust understanding of the potential effects of continued global development.

  20. Assessment of the risk of pollution by sulfur compounds and heavy metals in soils located in the proximity of a disused for 20 years sulfur mine (SE Poland).

    Science.gov (United States)

    Sołek-Podwika, Katarzyna; Ciarkowska, Krystyna; Kaleta, Dorota

    2016-09-15

    The study assessed the long-term effects of anthropogenic pressure of the sulfur industry on turf-covered soils located in the vicinity of the sulfur mine Grzybów. The study assumes that 20 years which elapsed since the end of the exploitation of sulfur is a period sufficiently long for the content of sulfur compounds in soils not to exceed the permissible level and that soil of the region can be classified as not contaminated. A part of the study involved identification of changes in the contents Stot. and SSO4(2-) in soils collected in the 1970s and early twenty-first century. It was also traced the relationship between the content of sulfur compounds and selected soil properties and estimated risk of soil environment pollution by heavy metals. Mean contents of trace elements studied amounted to 10.2-10.8 mg kg(-1) for Pb, 14.3-39.4 mg kg(-1) for Zn, 0.2-0.4 mg kg(-1) for Cd, 3.8-32.2 mg kg(-1) for Cr, 2.7-15.1 mg kg(-1) for Cu and 2.9-18.7 mg kg(-1) for Ni. Based on the results of SSO4(2-) content in soils collected at a distance of 1 km from the mine, it was found out that despite the passage of years, the amount of this type of sulfur still is increased and exceeds 0.14 g kg(-1). As the distance from the mine grew lower (from 0.017 to 0.03 g kg(-1)) average content of the sulfur form was observed. In the studied soil material we found generally positive, strong correlation between the Stot. and SSO4(2-) content and analyzed trace elements. The degree of contamination of examined soils with heavy metals was estimated on the basis of the integrated pollution index, which pointed to a moderate and low level of antropogenization of this area. In addition, the relationship between the determined characteristics of soils (Corg. contents, the fraction heavy metals confirms that the trace elements present in soils do not occur in mobile forms in the soil solution. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Relationship between corrosion and the biological sulfur cycle: A review

    Energy Technology Data Exchange (ETDEWEB)

    Little, B.J.; Ray, R.I.; Pope, R.K.

    2000-04-01

    Sulfur and sulfur compounds can produce pitting, crevice corrosion, dealloying, stress corrosion cracking, and stress-oriented hydrogen-induced cracking of susceptible metals and alloys. Even though the metabolic by-products of the biological sulfur cycle are extremely corrosive, there are no correlations between numbers and types of sulfur-related organisms and the probability or rate of corrosion, Determination of specific mechanisms for corrosion caused by microbiologically mediated oxidation and reduction of sulfur and sulfur compounds is complicated by the variety of potential metabolic-energy sources and by-products; the coexistence of reduced and oxidized sulfur species; competing reactions with inorganic and organic compounds; and the versatility and adaptability of microorganisms in biofilms. The microbial ecology of sulfur-rich environments is poorly understood because of the association of aerobes and anaerobes and the mutualism or succession of heterotrophs to autotrophs. The physical scale over which the sulfur cycle influences corrosion varies with the environment. The complete sulfur cycle of oxidation and reduction reactions can take place in macroenvironments, including sewers and polluted harbors, or within the microenvironment of biofilms. In this review, reactions of sulfur and sulfur compounds resulting in corrosion were discussed in the context of environmental processes important to corrosion.

  2. Emission of volatile sulfur compounds during composting of municipal solid waste (MSW)

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hongyu [Beijing Building Materials Academy of Science Research/State Key Laboratory of Solid Waste Reuse for Building Material, Beijing 100041 (China); College of Resources and Environment Sciences, China Agricultural University, Beijing 100094 (China); Schuchardt, Frank [Johann Heinrich von Thuenen-Institute, Institute of Agricultural Technology and Biosystems Engineering, Bundesallee 50, 38116 Braunschweig (Germany); Li, Guoxue, E-mail: ligx@cau.edu.cn [College of Resources and Environment Sciences, China Agricultural University, Beijing 100094 (China); Yang, Jinbing; Yang, Qingyuan [College of Resources and Environment Sciences, China Agricultural University, Beijing 100094 (China)

    2013-04-15

    Highlights: ► We compare the volatile sulfur compounds (VSCs) emissions during three types of municipal solid wastes (MSWs) composting. ► The VSCs released from the kitchen waste composting was significantly higher than that from 15–80 mm fraction of MSW. ► Among the five VSCs, H{sub 2}S was the most abundant compound with 39.0–43.0% of total VSCs released. ► Addition of 20% cornstalks could significantly reduce the VSCs emissions during kitchen waste composting. - Abstract: Volatile sulfur compounds (VSCs) are the main source for malodor from composting plants. In this study, the VSCs generated from composting of 15–80 mm municipal solid waste (T0), kitchen waste (T1) and kitchen waste mixed dry cornstalks (T2) were measured in 60 L reactors with forced aeration for a period of 30 days. The VSCs detected in all treatments were hydrogen sulfide (H{sub 2}S), methyl mercaptan (MM), dimethyl sulfide (DMS), carbon bisulfide (CS{sub 2}) and dimethyl disulfide (DMDS). Over 90% of the VSCs emissions occurred during the first 15 days, and reached their peak values at days 4–7. The emission profiles of five VSCs species were significantly correlated with internal materials temperature and outlet O{sub 2} concentration (p < 0.05). Total emissions of the VSCs were 216.1, 379.3 and 126.0 mg kg{sup −1} (dry matter) for T0, T1 and T2, respectively. Among the five VSCs, H{sub 2}S was the most abundant compound with 39.0–43.0% of total VSCs released. Composting of kitchen waste from separate collection posed a negative influence on the VSC and leachate production because of its high moisture content. An addition of dry cornstalks at a mixing ratio of 4:1 (wet weight) could significantly reduce the VSCs emissions and avoid leachate. Compared to pure kitchen waste, VSCs were reduced 66.8%.

  3. Critical review of animal carcinogenesis by cadmium and its inorganic compounds

    International Nuclear Information System (INIS)

    Maximilien, R.; Dero, B.

    1990-01-01

    Animal carcinogenic biassays relative to 6 inorganic cadmium substances (cadmium metal, cadmium oxide, cadmium sulfide, cadmium sulfate, cadmium chloride and cadmium acetate) are reviewed (speciation). Critical evaluation of literature data on carcinogenicity has been performed by making reference to E.C. guidelines of good laboratory practice. There are few data on routes relevant for human risk assessment: experiments on inhalation demonstrate lung carcinogenicity of cadmium oxide, cadmium sulfide, cadmium sulfate and cadmium chloride in rats but not in mice nor in hamsters; no carcinogenic effects of cadmium compounds are observed following oral administration. For routes of less or no relevance for human risk assessment, some results are clearly positive: subcutaneous injection induces cancers in situ (various cadmium compounds), testicular tumours (cadmium sulfate and cadmium chloride) and prostatic tumours (cadmium chloride) but such effects are not observed using relevant malignancies in rats. With respect to other no relevant routes (intraperitoneal, intrarenal...) tumours are incidentally produced in situ, but not in remote organs. Numerous studies fail to demonstrate cadmium carcinogenicity, but methodologically acceptable negative ones are very limited in number. Accordingly strain dependent effects and dose effect relationship could not be thoroughly assessed

  4. Pore structure modification of cement concretes by impregnation with sulfur-containing compounds

    Directory of Open Access Journals (Sweden)

    YANAKHMETOV Marat Rafisovich

    2015-02-01

    Full Text Available The authors study how the impregnation with sulfur-containing compounds changes the concrete pore structure and how it influences on the water absorption and watertightness. The results of this research indicate that impregnation of cement concrete with water-based solution of polysulphide modifies pore structure of cement concrete in such a way that it decreases total and effective porosity, reduces water absorption and increases watertightness. The proposed impregnation based on mineral helps to protect for a long time the most vulnerable parts of buildings – basements, foundations, as well as places on the facades of buildings exposed to rain, snow and groundwater. Application of the new product in the construction industry can increase the durability of materials, preventing the destruction processes caused by weathering, remove excess moisture in damp basements. The surfaces treated by protective compounds acquire antisoiling properties for a long time, and due to reduced thermal conductivity the cost of heating buildings is decreased. The effectiveness of the actions and the relatively low cost of proposed hydrophobizator makes it possible to spread widely the proposed protection method for building structures.

  5. Influence of gender and stress on the volatile sulfur compounds and stress biomarkers production.

    Science.gov (United States)

    Lima, P O; Calil, C M; Marcondes, F K

    2013-05-01

    Stress and menstrual cycle have been described as factors influencing bad breath, as they can alter oral homeostasis and contribute to the production of volatile sulfur compounds (VSC). Considering that the experimenter's and volunteer's gender may influence the volunteer's responses to stress, the aim of this work was to evaluate the influence of stress and gender on the production of VSC and salivary biomarkers. The experimental acute stress was induced by the Video-Recorded Stroop Color-Word Test (VRSCWT). The VSC, salivary proteins, and cardiovascular parameters were measured before and after VRSCWT. The VRSCWT induced significant increase in total VSC, hydrogen sulfide, and blood pressure values in men and women. Women presented higher values of both these compounds than men. The increase in systolic blood pressure was more pronounced when subjects were evaluated by an experimenter of the opposite gender. When women were evaluated by a member of the opposite gender, they showed significant increases in salivary alpha-amylase and cortisol compared with baseline values. Thus, the results showed that VRSCWT induced acute stress, which increased VSC production, and these effects were shown to be influenced by the gender. © 2012 John Wiley & Sons A/S.

  6. Thermal stability of inorganic and organic compounds in atmospheric particulate matter

    Science.gov (United States)

    Perrino, Cinzia; Marconi, Elisabetta; Tofful, Luca; Farao, Carmela; Materazzi, Stefano; Canepari, Silvia

    2012-07-01

    The thermal behaviour of atmospheric particulate matter (PM) has been investigated by using different analytical approaches to explore the added value offered by these technique in environmental studies. The thermogravimetric analysis (TGA), carried out on both certified material and real PM samples, has shown that several mass losses can be detected starting from 80 °C up to above 500 °C, when pyrolysis occur. Thermo-optical analysis of PM and ion chromatographic analysis of the residual have shown that the mass losses in the temperature range 80-180 °C are not justified by the release of either organic or inorganic compounds; it can be thus attributed to the release of weakly and strongly bound water. Release of water has also been evidenced in the temperature range 225-275 °C. The release of ammonium chloride and nitrate has been detected only above 80 °C. This indicates that the release of nitric acid, hydrochloric acid and ammonia, which is observed downstream of the filters during the sampling of atmospheric PM at ambient temperature, cannot be reproduced off-line, after the end of the sampling. We successfully explored one of the possible explanations, that is the desorption of HNO3, HCl and NH3 adsorbed on collected particles. NH4NO3 and NH4Cl, which can be thermally released by the filter, exhibit a different thermal behaviour from NaNO3 and NaCl, which are thermally stable up to 370 °C. This different behaviour can be used to discriminate between natural and secondary sources of atmospheric inorganic salts, as the interconversion that is observed when heating mixtures of pure salts resulted to be not relevant when heating real PM samples.

  7. Effect of naphtha diluent on greenhouse gases and reduced sulfur compounds emissions from oil sands tailings.

    Science.gov (United States)

    Gee, Kathleen F; Poon, Ho Yin; Hashisho, Zaher; Ulrich, Ania C

    2017-11-15

    The long-term storage of oil sands tailings has resulted in the evolution of greenhouse gases (CH 4 and CO 2 ) as a result of residual organics biodegradation. Recent studies have identified black, sulfidic zones below the tailings-water interface, which may be producing toxic sulfur-containing gases. An anaerobic mesocosm study was conducted over an 11-week period to characterize the evolution of CH 4 , CO 2 and reduced sulfur compounds (RSCs) (including H 2 S) in tailings as it relates to naphtha-containing diluent concentrations (0.2, 0.8, and 1.5% w/v) and microbial activity. Our results showed that RSCs were produced first at 0.12μmol°RSCs/mL MFT (1.5% w/v diluent treatment). RSCs contribution (from highest to lowest) was H 2 S and 2-methylthiophene>2.5-dimethylthiophene>3-methylthiophene>thiofuran>butyl mercaptan>carbonyl sulfide, where H 2 S and 2-methylthiophene contributed 81% of the gas produced. CH 4 and CO 2 production occurred after week 5 at 40.7μmolCH 4 /mL MFT and 5.9μmolCO 2 /mL MFT (1.5% w/v diluent treatment). The amount of H 2 S and CH 4 generated is correlated to the amount of diluent present and to microbial activity as shown by corresponding increases in sulfate-reducers' Dissimilatory sulfite reductase (DsrAB) gene and methanogens' methyl-coenzyme M reductase (MCR) gene. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Preparation of inorganic crystalline compounds induced by ionizing, UV and laser radiation

    International Nuclear Information System (INIS)

    Cuba, V.; Pavelkova, T.; Barta, J.; Indrei, J.; Gbur, T.; Pospisil, M.; Mucka, V.; Docekalova, Z.; Zavadilova, A.; Vlk, M.

    2011-01-01

    Complete text of publication follows. Radiation methods represent powerful tool for synthesis of various inorganic materials. Study of solid particles formation from solutions in the field of UV or ionizing radiation is one of the very promising and long term pursued trends in photochemistry and radiation chemistry. The motivation may be various, either preparation of new materials or removal of hazardous contaminants (e.g. heavy metals) from wastewater. This work deals with preparation of some metal oxides, synthetic garnets and spinel structures via irradiation of aqueous solutions containing precursors, i.e. soluble metal salts, radical scavengers and/or macromolecular stabilizers. Namely, results on radiation induced preparation of nickel, zinc, yttrium and aluminium oxides are summarized, as well as zinc peroxide, yttrium / lutetium - aluminium garnets and cobalt(II) aluminate. 60 Co irradiator, linear electron accelerator, medium pressure UV lamp and solid state laser were used as the sources of radiation. Aside from preparation, various physico-chemical and structural properties of compounds prepared were also studied. All used modifications of radiation method are rather convenient and simple, and yield (nano)powder materials with interesting characteristics. Prepared materials generally have high chemical purity, high specific surface area and narrow distribution of particles size (ranging in tens of nm). Generally, all types of irradiation result in materials with comparable properties and structural characteristics; but in the case of synthetic garnets and spinels, preparation using UV-radiation seems to be the most convenient for their preparation. Among compounds discussed, only zinc oxide and zinc peroxide were prepared directly via irradiation. For preparation of other crystalline compounds, additional heat treatment (at low temperature) of amorphous solid phase formed under irradiation was necessary.

  9. Planetary Sources for Reducing Sulfur Compounds for Cyanosulfidic Origins of Life Chemistry

    Science.gov (United States)

    Ranjan, S.; Todd, Z. R.; Sutherland, J.; Sasselov, D. D.

    2017-12-01

    A key challenge in origin-of-life studies is understanding the chemistry that lead to the origin of the key biomolecules of life, such as the components of nucleic acids, sugars, lipids, and proteins. Prebiotic reaction networks based upon reductive homologation of nitriles (e.g., Patel et al. 2015), are building a tantalizing picture of sustained abiotic synthesis of activated ribonucleotides, amino acids and lipid precursors under environmental conditions thought to have been available on early Earth. Sulfidic anions in aqueous solution (e.g., HS-, HSO3-) under near-UV irradiation play important roles in these chemical pathways. However, the sources and availability of these anions on early Earth have not yet been quantitatively constrained. Here, we evaluate the potential for the atmosphere to serve as a source of sulfidic anions, via dissolution of volcanically-outgassed SO2 and H2S into water reservoirs. We combine photochemical modeling from the literature (Hu et al. 2013) with equilibrium chemistry calculations to place constraints on the partial pressures of SO2 and H2S required to reach the elevated concentrations of sulfidic anions (≥1 μM) thought to be necessary for prebiotic chemistry. We find that micromolar levels of SO2-derived anions (HSO3-, SO3(2-)) are possible through simple exposure of aqueous reservoirs like shallow lakes to the atmosphere, assuming total sulfur emission flux comparable to today. Millimolar levels of these compounds are available during the epochs of elevated volcanism, due to elevated sulfur emission flux. Radiative transfer modeling suggests the atmospheric sulfur will not block the near-UV radiation also required for the cyanosulfidic chemistry. However, H2S-derived anions (e.g., HS-) reach only sub-micromolar levels from atmospheric sources, meaning that prebiotic chemistry invoking such molecules must invoke specialized, local sources. Prebiotic chemistry invoking SO2-derived anions may be considered more robust than

  10. Application of Atmospheric Pressure Photoionization H/D-exchange Mass Spectrometry for Speciation of Sulfur-containing Compounds.

    Science.gov (United States)

    Acter, Thamina; Kim, Donghwi; Ahmed, Arif; Ha, Ji-Hyoung; Kim, Sunghwan

    2017-08-01

    Herein we report the observation of atmospheric pressure in-source hydrogen-deuterium exchange (HDX) of thiol group for the first time. The HDX for thiol group was optimized for positive atmospheric pressure photoionization (APPI) mass spectrometry (MS). The optimized HDX-MS was applied for 31 model compounds (thiols, thiophenes, and sulfides) to demonstrate that exchanged peaks were observed only for thiols. The optimized method has been successfully applied to the isolated fractions of sulfur-rich oil samples. The exchange of one and two thiol hydrogens with deuterium was observed in the thiol fraction; no HDX was observed in the other fractions. Thus, the results presented in this study demonstrate that the HDX-MS method using APPI ionization source can be effective for speciation of sulfur compounds. This method has the potential to be used to access corrosion problems caused by thiol-containing compounds. Graphical Abstract ᅟ.

  11. Simultaneous determination of inorganic mercury and methylmercury compounds in natural waters

    Energy Technology Data Exchange (ETDEWEB)

    Logar, Martina; Horvat, Milena [Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Akagi, Hirokatsu [National Institute for Minamata Disease, 4058-18 Hama, Minamata, Kumamoto 867-0008 (Japan); Pihlar, Boris [Faculty of Chemistry and Chemical Technology, University of Ljubljana, Askerceva 5, 1000 Ljubljana (Slovenia)

    2002-11-01

    The purpose of the present work was to develop a simple, rapid, sensitive and accurate method for the simultaneous determination of inorganic mercury (Hg{sup 2+}) and monomethylmercury compounds (MeHg) in natural water samples at the pg L{sup -1} level. The method is based on the simultaneous extraction of MeHg and Hg{sup 2+}dithizonates into an organic solvent (toluene) after acidification of about 300 mL of a water sample, followed by back extraction into an aqueous solution of Na {sub 2}S, removal of H {sub 2}S by purging with N {sub 2}, subsequent ethylation with sodium tetraethylborate, room temperature precollection on Tenax, isothermal gas chromatographic separation (GC), pyrolysis and cold vapour atomic fluorescence spectrometric detection (CV AFS) of mercury. The limit of detection calculated on the basis of three times the standard deviation of the blank was about 0.006 ng L {sup -1} for MeHg and 0.06 ng L {sup -1} for Hg {sup 2+}when 300 mL of water was analysed. The repeatability of the results was about 5% for MeHg and 10% for Hg {sup 2+}. Recoveries were 90-110% for both species. (orig.)

  12. Cultivating Chlorella vulgaris and Scenedesmus quadricauda microalgae to degrade inorganic compounds and pesticides in water.

    Science.gov (United States)

    Baglieri, Andrea; Sidella, Sarah; Barone, Valeria; Fragalà, Ferdinando; Silkina, Alla; Nègre, Michèle; Gennari, Mara

    2016-09-01

    This work evaluates the possibility of cultivating Scenedesmus quadricauda and Chlorella vulgaris microalgae in wastewater from the hydroponic cultivation of tomatoes with the aim of purifying the water. S. quadricauda and C. vulgaris were also used in purification tests carried out on water contaminated by the following active ingredients: metalaxyl, pyrimethanil, fenhexamid, iprodione, and triclopyr. Fifty-six days after the inoculum was placed, a reduction was found in the concentration of nitric nitrogen, ammonia nitrogen, and soluble and total phosphorus. The decrease was 99, 83, 94, and 94 %, respectively, for C. vulgaris and 99, 5, 88, and 89 %, respectively, for S. quadricauda. When the microalgae were present, all the agrochemicals tested were removed more quickly from the water than from the sterile control (BG11). The increase in the rate of degradation was in the order metalaxyl > fenhexamid > iprodione > triclopyr > pyrimethanil. It was demonstrated that there was a real degradation of fenhexamid, metalaxyl, triclopyr, and iprodione, while in the case of pyrimethanil, the active ingredient removed from the substrate was absorbed onto the cells of the microalgae. It was also found that the agrochemicals used in the tests had no significant effect on the growth of the two microalgae. The experiment highlighted the possibility of using cultivations of C. vulgaris and S. quadricauda as purification systems for agricultural wastewater which contains eutrophic inorganic compounds such as nitrates and phosphates and also different types of pesticides.

  13. Tritium isolation from lithium inorganic compounds applicable to thermonuclear reactor breeding blanket

    International Nuclear Information System (INIS)

    Vasil'ev, V.G.; Ershova, Z.V.; Nikiforov, A.S.

    1982-01-01

    Tritium separation from inorganic lithium compounds: Li 2 O, LiAlO 2 , Li 2 SiO 3 , Li 4 SiO 4 , LiF, LiBeF 3 , Li 2 BeF 4 irradiated with a beam of a gamma facility and a nuclear reactor, has been studied. In the first case the gas phase is absent. In the latter one- the tritium amount in the gas does not exceed 1-2% of its total amount in the salt. Based on the EPR spectra of irradiated salts the concentrations of paramagnetic centres are calculated. It is shown that during thermal annealing the main portion of tritium in the gas phase is in the form of oxide (HTO, T 2 O). Tritium is separated from lithium fluoroberyllates in the form of hydrogen (HT, T 2 ). The kinetics of tritium oxide isolation from irradiated lithium oxide aluminate, metha- and orthosilicates, lithium sulphate has been studied. The activation energies of tritium oxide separation process are presented. A supposition is made that chemical reaction of the HTO (T 2 O) or HT(T 2 ) or HF(TF) formation is a limiting stage. Clarification of the process stage limiting the rate of tritium recovery will permit to evaluate conditions for the optimum work of lithium material in the blanket, lithium zone to select the lithium element structure and temperature regime of irradiation

  14. Atmospheric Deposition of Inorganic Elements and Organic Compounds at the Inlets of the Venice Lagoon

    Directory of Open Access Journals (Sweden)

    E. Morabito

    2014-01-01

    Full Text Available The Venice Lagoon is subjected to long-range transport of contaminants via aerosol from the near Po Valley. Moreover, it is an area with significant local anthropogenic emissions due to the industrial area of Porto Marghera, the urban centres, and the glass factories and with emissions by ships traffic within the Lagoon. Furthermore, since 2005, the Lagoon has also been affected by the construction of the MOSE (Modulo Sperimentale Elettromeccanico—Electromechanical Experimental Module mobile dams, as a barrier against the high tide. This work presents and discusses the results from chemical analyses of bulk depositions, carried out in different sites of the Venice Lagoon. Fluxes of pollutants were also statistically analysed on PCA with the aim of investigating the spatial variability of depositions and their correlation with precipitations. Fluxes of inorganic pollutants depend differently on precipitations, while organic compounds show a more seasonal trend. The statistical analysis showed that the site in the northern Lagoon has lower and almost homogeneous fluxes of pollutants, while the other sites registered more variable concentrations. The study also provided important information about the annual trend of pollutants and their evolution over a period of about five years, from 2005 to 2010.

  15. Isotopically labeled sulfur compounds and synthetic selenium and tellurium analogues to study sulfur metabolism in marine bacteria

    Directory of Open Access Journals (Sweden)

    Nelson L. Brock

    2013-05-01

    Full Text Available Members of the marine Roseobacter clade can degrade dimethylsulfoniopropionate (DMSP via competing pathways releasing either methanethiol (MeSH or dimethyl sulfide (DMS. Deuterium-labeled [2H6]DMSP and the synthetic DMSP analogue dimethyltelluriopropionate (DMTeP were used in feeding experiments with the Roseobacter clade members Phaeobacter gallaeciensis DSM 17395 and Ruegeria pomeroyi DSS-3, and their volatile metabolites were analyzed by closed-loop stripping and solid-phase microextraction coupled to GC–MS. Feeding experiments with [2H6]DMSP resulted in the incorporation of a deuterium label into MeSH and DMS. Knockout of relevant genes from the known DMSP demethylation pathway to MeSH showed in both species a residual production of [2H3]MeSH, suggesting that a second demethylation pathway is active. The role of DMSP degradation pathways for MeSH and DMS formation was further investigated by using the synthetic analogue DMTeP as a probe in feeding experiments with the wild-type strain and knockout mutants. Feeding of DMTeP to the R. pomeroyi knockout mutant resulted in a diminished, but not abolished production of demethylation pathway products. These results further corroborated the proposed second demethylation activity in R. pomeroyi. Isotopically labeled [2H3]methionine and 34SO42−, synthesized from elemental 34S8, were tested to identify alternative sulfur sources besides DMSP for the MeSH production in P. gallaeciensis. Methionine proved to be a viable sulfur source for the MeSH volatiles, whereas incorporation of labeling from sulfate was not observed. Moreover, the utilization of selenite and selenate salts by marine alphaproteobacteria for the production of methylated selenium volatiles was explored and resulted in the production of numerous methaneselenol-derived volatiles via reduction and methylation. The pathway of selenate/selenite reduction, however, proved to be strictly separated from sulfate reduction.

  16. Permanganate oxidation of sulfur compounds to prevent poisoning of Pd catalysts in water treatment processes.

    Science.gov (United States)

    Angeles-Wedler, Dalia; Mackenzie, Katrin; Kopinke, Frank-Dieter

    2008-08-01

    The practical application of Pd-catalyzed water treatment processes is impeded by catalyst poisoning by reduced sulfur compounds (RSCs). In this study, the potential of permanganate as a selective oxidant for the removal of microbially generated RSCs in water and as a regeneration agent for S-poisoned catalysts was evaluated. Hydrodechlorination using Pd/Al2O3 was carried out as a probe reaction in permanganate-pretreated water. The activity of the Pd catalysts in the successfully pretreated reaction medium was similar to that in deionized water. The catalyst showed no deactivation behavior in the presence of permanganate at a concentration level or = 0.08 mM, a significant but temporary inhibition of the catalytic dechlorination was observed. Unprotected Pd/Al2O3, which had been completely poisoned by sulfide, was reactivated by a combined treatment with permanganate and hydrazine. However, the anthropogenic water pollutants thiophene and carbon disulfide were resistant against permanganate. Together with the preoxidation of catalyst poisons, hydrophobic protection of the catalysts was studied. Pd/zeolite and various hydrophobically coated catalysts showed a higher stability against ionic poisons and permanganate than the uncoated catalyst. By means of a combination of oxidative water pretreatment and hydrophobic catalyst protection, we provide a new tool to harness the potential of Pd-catalyzed hydrodehalogenation for the treatment of real waters.

  17. Effects of stress hormones on the production of volatile sulfur compounds by periodontopathogenic bacteria

    Directory of Open Access Journals (Sweden)

    Caroline Morini Calil

    2014-06-01

    Full Text Available Little is known about the effects of stress hormones on the etiologic agents of halitosis. Thus, the aim of this study was to evaluate in vitro the effects of adrenaline (ADR, noradrenaline (NA and cortisol (CORT on bacteria that produce volatile sulfur compounds (VSC, the major gases responsible for bad breath. Cultures of Fusobacterium nucleatum (Fn, Porphyromonas endodontalis (Pe, Prevotella intermedia (Pi and Porphyromonas gingivalis (Pg were exposed to 50 µM ADR, NA and CORT or equivalent volumes of sterile water as controls for 12 and 24 h. Growth was evaluated based on absorbance at 660 nm. Portable gas chromatography was used to measure VSC concentrations. Kruskal-Wallis and the Dunn post-hoc test were used to compare the groups. For Fn, ADR, NA and CORT significantly reduced bacterial growth after 12 h and 24 h (p 0.05. In the Pi cultures, ADR, NA and CORT increased H2S (p < 0.05. Catecholamines and cortisol can interfere with growth and H2S production of sub-gingival species in vitro. This process appears to be complex and supports the association between stress and the production of VSC.

  18. Tissue-Specific Accumulation of Sulfur Compounds and Saponins in Different Parts of Garlic Cloves from Purple and White Ecotypes.

    Science.gov (United States)

    Diretto, Gianfranco; Rubio-Moraga, Angela; Argandoña, Javier; Castillo, Purificación; Gómez-Gómez, Lourdes; Ahrazem, Oussama

    2017-08-20

    This study set out to determine the distribution of sulfur compounds and saponin metabolites in different parts of garlic cloves. Three fractions from purple and white garlic ecotypes were obtained: the tunic (SS), internal (IS) and external (ES) parts of the clove. Liquid Chromatography coupled to High Resolution Mass spectrometry (LC-HRMS), together with bioinformatics including Principal Component Analysis (PCA), Hierarchical Clustering (HCL) and correlation network analyses were carried out. Results showed that the distribution of these metabolites in the different parts of garlic bulbs was different for the purple and the white ecotypes, with the main difference being a slightly higher number of sulfur compounds in purple garlic. The SS fraction in purple garlic had a higher content of sulfur metabolites, while the ES in white garlic was more enriched by these compounds. The correlation network indicated that diallyl disulfide was the most relevant metabolite with regards to sulfur compound metabolism in garlic. The total number of saponins was almost 40-fold higher in purple garlic than in the white variety, with ES having the highest content. Interestingly, five saponins including desgalactotigonin-rhamnose, proto-desgalactotigonin, proto-desgalactotigonin-rhamnose, voghieroside D1, sativoside B1-rhamnose and sativoside R1 were exclusive to the purple variety. Data obtained from saponin analyses revealed a very different network between white and purple garlic, thus suggesting a very robust and tight coregulation of saponin metabolism in garlic. Findings in this study point to the possibility of using tunics from purple garlic in the food and medical industries, since it contains many functional compounds which can be exploited as ingredients.

  19. Acidithiobacillus caldus sulfur oxidation model based on transcriptome analysis between the wild type and sulfur oxygenase reductase defective mutant.

    Directory of Open Access Journals (Sweden)

    Linxu Chen

    Full Text Available Acidithiobacillus caldus (A. caldus is widely used in bio-leaching. It gains energy and electrons from oxidation of elemental sulfur and reduced inorganic sulfur compounds (RISCs for carbon dioxide fixation and growth. Genomic analyses suggest that its sulfur oxidation system involves a truncated sulfur oxidation (Sox system (omitting SoxCD, non-Sox sulfur oxidation system similar to the sulfur oxidation in A. ferrooxidans, and sulfur oxygenase reductase (SOR. The complexity of the sulfur oxidation system of A. caldus generates a big obstacle on the research of its sulfur oxidation mechanism. However, the development of genetic manipulation method for A. caldus in recent years provides powerful tools for constructing genetic mutants to study the sulfur oxidation system.An A. caldus mutant lacking the sulfur oxygenase reductase gene (sor was created and its growth abilities were measured in media using elemental sulfur (S(0 and tetrathionate (K(2S(4O(6 as the substrates, respectively. Then, comparative transcriptome analysis (microarrays and real-time quantitative PCR of the wild type and the Δsor mutant in S(0 and K(2S(4O(6 media were employed to detect the differentially expressed genes involved in sulfur oxidation. SOR was concluded to oxidize the cytoplasmic elemental sulfur, but could not couple the sulfur oxidation with the electron transfer chain or substrate-level phosphorylation. Other elemental sulfur oxidation pathways including sulfur diooxygenase (SDO and heterodisulfide reductase (HDR, the truncated Sox pathway, and the S(4I pathway for hydrolysis of tetrathionate and oxidation of thiosulfate in A. caldus are proposed according to expression patterns of sulfur oxidation genes and growth abilities of the wild type and the mutant in different substrates media.An integrated sulfur oxidation model with various sulfur oxidation pathways of A. caldus is proposed and the features of this model are summarized.

  20. Biologically produced sulfur

    NARCIS (Netherlands)

    Kleinjan, W.E.; Keizer, de A.; Janssen, A.J.H.

    2003-01-01

    Sulfur compound oxidizing bacteria produce sulfur as an intermediate in the oxidation of hydrogen sulfide to sulfate. Sulfur produced by these microorganisms can be stored in sulfur globules, located either inside or outside the cell. Excreted sulfur globules are colloidal particles which are

  1. Modeling the Distribution of Sulfur Compounds in a Large Two Stroke Diesel Engine

    DEFF Research Database (Denmark)

    Cordtz, Rasmus Lage; Schramm, Jesper; Andreasen, Anders

    2013-01-01

    In many years large low speed marine diesel engines have consumed heavy fuel oils with sulfur contents in the order of 2.5 - 4.5wt%. Present legislations require that the fuel sulfur is reduced and in near future the limit will be 0.5wt% globally. During combustion most of the sulfur is oxidized...... conditions and sulfur feed. This work presents a computational model of a large low speed two-stroke diesel engine where a 0D multi-zone approach including a detailed reaction mechanism is employed in order to investigate in cylinder formation of gaseous SO3 where fuel injection rates are determined using...... experimental pressure traces. Similarly to NO the SO3 is very sensitive to the rate that fresh air mixes with hot combustion products. Therefore a simple mixing rate is proposed and calibrated in order to meet experimental results of NO. Generally 3 - 5 % of the injected sulfur is oxidized to SO3...

  2. Analysis of Volatile Organic and Sulfur Compounds in Air Near a Pulp Paper Mill in North-Central Idaho

    Science.gov (United States)

    Johnston, N. A. C.; Bundy, B. A.; Andrew, J. P.; Grimm, B. K.; Ketcherside, D.; Rivero-Zevallos, J. A.; Uhlorn, R. P.

    2017-12-01

    Lewiston, Idaho is a small city in the Snake River Valley bordering North-Central Idaho and Southeastern Washington, with a population of over 40,000 including the surrounding areas. One of the main industries and employers in the region is a kraft paper mill in North Lewiston, which results in odorous levels of sulfur air pollutants there. The Idaho Department of Environmental Quality has an air monitoring station in Lewiston but measures only air particulate matter (PM). Surprisingly, not much long-term data exists on this area for specific air constituents such as volatile organics, hazardous air pollutants, and sulfur compounds. One year-long study conducted in 2006-2007 by the Nez Perce Tribe found high formaldehyde levels in the area, and warranted further study in July of 2016-2017. Our ongoing study began in the fall of 2016 and investigates the seasonal air composition in the Lewiston area. Specifically, active air sampling via sorbent tubes and analysis by thermal desorption gas chromatography-mass spectrometry (TD-GC-MS). was utilized to measure over 50 volatile organic compounds, hazardous air pollutants, and sulfurous compounds in ambient air (adapted from EPA Method TO-17). Seasonal, diurnal, and spatial variations in air composition were explored with weekly to monthly grab sampling. Dimethyl sulfide (DMS) and dimethyl disulfide (DMDS) were the primary sulfur compounds detected, and these varied considerably depending on time of day, season, location and meteorology. DMS was more prevalent in the summer months, while DMDS was more prevalent in the spring. Elevated concentrations of benzene and chloroform were found in the region during 2017, with average values of short term grab samples over three times the acceptable ambient concentrations in Idaho. These levels did not persist during longer term sampling of 12-hours, however further monitoring is needed to assess a potential health concern.

  3. Sulfur and nitrogen compounds in air and precipitation over the former Soviet Union in 1980-1995

    Energy Technology Data Exchange (ETDEWEB)

    Paramonov, S.; Ryaboshapko, A.; Gromov, S. [Inst. of Global Climate and Ecology, Moscow (Russian Federation); Granat, L.; Rodhe, H. [Stockholm Univ. (Sweden). Dept. of Meteorology

    1999-12-01

    Published information on sulfur and nitrogen compounds in air and precipitation in background regions of the Former Soviet Union (F SU) was collected and analyzed. Bad or doubtful data were removed. The spatial patterns of sulphur and nitrogen compounds indicate that western and southern regions are the most polluted and eastern Siberia the cleanest. Dry deposition of oxidized sulfur and nitrogen on all the F SU territory was estimated to 3.3 Mt S and 1.6 Mt N per year (an average of 0. 15 gS/m{sup 2} yr and 0.07 gN/m{sup 2} yr). Deposition with precipitation was estimated to 14.7 Mt S and 7.9 Mt N per year (an average of 0.66 gS/m{sup 2}yr and 0.35 gN/m{sup 2}yr). Deposition fluxes are largest during the warm season. Data from the GAW monitoring network during the period 1980-1995 showed a visible increase of nitrate and ammonium in precipitation whereas the concentration of sulfate was rather stable. The sulfur dioxide concentration in air decreased significantly in several regions of the F SU during the decade 1980-1990. The data on nitrogen compounds in air are too limited to permit any firm conclusions regarding trends.

  4. On the reactive adsorption of ammonia on activated carbons modified by impregnation with inorganic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Bandosz, T.J.; Petit, C. [CUNY City College, New York, NY (United States). Dept. of Chemistry

    2009-10-15

    Ammonia adsorption was studied under dynamic conditions, at room temperature, on activated carbons of different origins (coal-based, wood-based and coconut-shell-based carbons) before and after their impregnation with various inorganic compounds including metal chlorides, metal oxides and polycations. The role of humidity was evaluated by running tests in both dry and moist conditions. Adsorbents were analyzed before and after exposure to ammonia by thermal analyses, sorption of nitrogen, potentiometric titration, X-ray diffraction and FTIR spectroscopy. Results of breakthrough tests show significant differences in terms of adsorption capacity depending on the parent carbon, the impregnates and the experimental conditions. It is found that surface chemistry governs ammonia adsorption on the impregnated carbons. More precisely, it was demonstrated that a proper combination of the surface pH, the strength, type and amount of functional groups present on the adsorbents' surface is a key point in ammonia uptake. Water can have either positive or negative effects on the performance of adsorbents. It can enhance NH{sub 3} adsorption capacity since it favors ammonia dissolution and thus enables reaction between ammonium ions and carboxylic groups from the carbons' surface. On the other hand, water can also reduce the performance from the strength of adsorption standpoint. It promotes dissolution of ammonia and that ammonia is first removed from the system when the adsorbent bed is purged with air. Ammonia, besides adsorption by van der Waals forces and dissolution in water, is also retained on the surface via reactive mechanisms such as acid-base reactions (Bronsted and Lewis) or complexation. Depending on the materials used and the experimental conditions, 6-47% ammonia adsorbed is strongly retained on the surface even when the bed is purged with air.

  5. UV absorption cross-sections of selected sulfur-containing compounds at temperatures up to 500°C

    DEFF Research Database (Denmark)

    Grosch, Helge; Fateev, Alexander; Clausen, Sønnik

    2015-01-01

    The temperature dependence of the ultraviolet absorption cross-sections of three different sulfur containing compounds, hydrogen sulfide (H2S), carbon disulfide (CS2) and carbonyl sulfide (OCS), are presented between 200nm and 360nm at a resolution of 0.018nm. The absorption cross-sections for each...... compound are initially compared with those available in the literature, followed by the discussion of the measurements and their spectral features at three temperatures up to 500°C/773K. Uncertainties in the measured absorption cross-sections are also addressed....

  6. Reduced sulfur compounds in gas from construction and demolition debris landfills.

    Science.gov (United States)

    Lee, Sue; Xu, Qiyong; Booth, Matthew; Townsend, Timothy G; Chadik, Paul; Bitton, Gabriel

    2006-01-01

    The biological conversion of sulfate from disposed gypsum drywall to hydrogen sulfide (H(2)S) in the anaerobic environment of a landfill results in odor problems and possible health concerns at many disposal facilities. To examine the extent and magnitude of such emissions, landfill gas samples from wells, soil vapor samples from the interface of the waste and cover soil, and ambient air samples, were collected from 10 construction and demolition (C&D) debris landfills in Florida and analyzed for H(2)S and other reduced sulfur compounds (RSC). H(2)S was detected in the well gas and soil vapor at all 10 sites. The concentrations in the ambient air above the surface of the landfill were much lower than those observed in the soil vapor, and no direct correlation was observed between the two sampling locations. Methyl mercaptan and carbonyl sulfide were the most frequently observed other RSC, though they occurred at smaller concentrations than H(2)S. This research confirmed the presence of H(2)S at C&D debris landfills. High concentrations of H(2)S may be a concern for employees working on the landfill site. These results indicate that workers should use proper personal protection at C&D debris landfills when involved in excavation, landfill gas collection, or confined spaces. The results indicate that H(2)S is sufficiently diluted in the atmosphere to not commonly pose acute health impacts for these landfill workers in normal working conditions. H(2)S concentrations were extremely variable with measurements occurring over a very large range (from less than 3 ppbv to 12,000 ppmv in the soil vapor and from less than 3 ppbv to 50 ppmv in ambient air). Possible reasons for the large intra- and inter-site variability observed include waste and soil heterogeneities, impact of weather conditions, and different site management practices.

  7. Removal of organic and inorganic sulfur from Ohio coal by combined physical and chemical process. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Attia, Y.A.; Zeky, M.El.; Lei, W.W.; Bavarian, F.; Yu, S. [Ohio State Univ., Columbus, OH (United States). Dept. of Materials Science and Engineering

    1989-04-28

    This project consisted of three sections. In the first part, the physical cleaning of Ohio coal by selective flocculation of ultrafine slurry was considered. In the second part, the mild oxidation process for removal of pyritic and organic sulfur.was investigated. Finally, in-the third part, the combined effects of these processes were studied. The physical cleaning and desulfurization of Ohio coal was achieved using selective flocculation of ultrafine coal slurry in conjunction with froth flotation as flocs separation method. The finely disseminated pyrite particles in Ohio coals, in particular Pittsburgh No.8 seam, make it necessary to use ultrafine ({minus}500 mesh) grinding to liberate the pyrite particles. Experiments were performed to identify the ``optimum`` operating conditions for selective flocculation process. The results indicated that the use of a totally hydrophobic flocculant (FR-7A) yielded the lowest levels of mineral matters and total sulfur contents. The use of a selective dispersant (PAAX) increased the rejection of pyritic sulfur further. In addition, different methods of floc separation techniques were tested. It was found that froth flotation system was the most efficient method for separation of small coal flocs.

  8. Comparative Evaluation of Sulfur Compounds Contents and Antiobesity Properties of Allium hookeri Prepared by Different Drying Methods

    Directory of Open Access Journals (Sweden)

    Min Hye Yang

    2017-01-01

    Full Text Available Despite the nutritional and medicinal values of Allium hookeri, its unique flavor (onion or garlic taste and smell coming from sulfur containing compounds limits its usage as functional food. For comparative study, A. hookeri roots were prepared under two different drying conditions, namely, low-temperature drying that minimizes the volatilization of sulfur components and hot-air drying that minimizes the garlic odor and spicy taste of A. hookeri. In GC/MS olfactory system, the odorous chemicals and organosulfur compounds such as diallyl trisulfide, dimethyl trisulfide, and dipropyl trisulfide were significantly decreased in hot-air drying compared to low-temperature drying. The spiciness and saltiness taste were noticeably reduced, while sourness, sweetness, and umami taste were significantly increased in hot-air dried A. hookeri according to electronic tongue. Although the content of volatile sulfur components was present at lower level, the administration of hot-air dried A. hookeri extract (100 mg/kg p.o. apparently prevented the body weight gain and improved insulin resistance in C57BL/6J obese mice receiving high fat diet. Results suggested that the hot-air dried A. hookeri possessing better taste and odor might be available as functional crop and bioactive diet supplement for the prevention and/or treatment of obesity.

  9. Emission characteristics of nitrogen- and sulfur-containing odorous compounds during different sewage sludge chemical conditioning processes

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Huan [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074 (China); School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Luo, Guang-Qian; Hu, Hong-Yun [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074 (China); Zhang, Qiang; Yang, Jia-Kuan [School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074 (China); Yao, Hong, E-mail: hyao@hust.edu.cn [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074 (China)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer NH{sub 3}, SO{sub 2}, H{sub 2}S and COS are emitted during different sludge conditioning processes. Black-Right-Pointing-Pointer H{sub 2}S and SO{sub 2} generation increase in the acidic environment created by H{sub 2}SO{sub 4}. Black-Right-Pointing-Pointer Fenton peroxidation facilitates the formation of COS. Black-Right-Pointing-Pointer CaO can reduce sulfur-containing gases emission via generation of calcium sulfate. Black-Right-Pointing-Pointer CaO leads to the conversion of free ammonia or protonated amine to volatile NH{sub 3}. - Abstract: Chemical conditioners are often used to enhance sewage sludge dewaterability through altering sludge properties and flocs structure, both affect odorous compounds emissions not only during sludge conditioning but also in subsequent sludge disposal. This study was to investigate emission characteristics of ammonia (NH{sub 3}), sulfur dioxide (SO{sub 2}), hydrogen sulfide (H{sub 2}S) and carbonyl sulfide (COS) generated from sewage sludge conditioned by three representative conditioners, i.e., organic polymers, iron salts and skeleton builders, F-S (Fenton's reagent and skeleton builders) composite conditioner. The results demonstrate that polyacrylamide (PAM) has an insignificant effect on emission characteristics of nitrogen- and sulfur-containing odorous compounds, because the properties, sulfur and nitrogen speciations are similar in PAM-conditioned sludge and raw sludge (RS). Significant increases of SO{sub 2} and H{sub 2}S emissions in the H{sub 2}SO{sub 4} conditioning process were observed due to the accelerated decomposition of sulfur-containing amino acids in acidic environment. Fenton peroxidation facilitates the formation of COS. CaO can reduce sulfur-containing gases emission via generation of calcium sulfate. However, under strong alkaline conditions, free ammonia or protonated amine in sludge can be easily converted to volatile ammonia, resulting in a significant

  10. Proteomic analysis of organic sulfur compound utilisation in Advenella mimigardefordensis strain DPN7T

    Science.gov (United States)

    Meinert, Christina; Brandt, Ulrike; Heine, Viktoria; Beyert, Jessica; Schmidl, Sina; Wübbeler, Jan Hendrik; Voigt, Birgit; Riedel, Katharina; Steinbüchel, Alexander

    2017-01-01

    2-Mercaptosuccinate (MS) and 3,3´-ditiodipropionate (DTDP) were discussed as precursor substance for production of polythioesters (PTE). Therefore, degradation of MS and DTDP was investigated in Advenella mimigardefordensis strain DPN7T, applying differential proteomic analysis, gene deletion and enzyme assays. Protein extracts of cells cultivated with MS, DTDP or 3-sulfinopropionic acid (SP) were compared with those cultivated with propionate (P) and/or succinate (S). The chaperone DnaK (ratio DTDP/P 9.2, 3SP/P 4.0, MS/S 6.1, DTDP/S 6.2) and a Do-like serine protease (DegP) were increased during utilization of all organic sulfur compounds. Furthermore, a putative bacterioferritin (locus tag MIM_c12960) showed high abundance (ratio DTDP/P 5.3, 3SP/P 3.2, MS/S 4.8, DTDP/S 3.9) and is probably involved in a thiol-specific stress response. The deletion of two genes encoding transcriptional regulators (LysR (MIM_c31370) and Xre (MIM_c31360)) in the close proximity of the relevant genes of DTDP catabolism (acdA, mdo and the genes encoding the enzymes of the methylcitric acid cycle; prpC,acnD, prpF and prpB) showed that these two regulators are essential for growth of A. mimigardefordensis strain DPN7T with DTDP and that they most probably regulate transcription of genes mandatory for this catabolic pathway. Furthermore, proteome analysis revealed a high abundance (ratio MS/S 10.9) of a hypothetical cupin-2-domain containing protein (MIM_c37420). This protein shows an amino acid sequence similarity of 60% to a newly identified MS dioxygenase from Variovorax paradoxus strain B4. Deletion of the gene and the adjacently located transcriptional regulator LysR, as well as heterologous expression of MIM_c37420, the putative mercaptosuccinate dioxygenase (Msdo) from A. mimigardefordensis, showed that this protein is the key enzyme of MS degradation in A. mimigardefordensis strain DPN7T (KM 0.2 mM, specific activity 17.1 μmol mg-1 min-1) and is controlled by LysR (MIM_c37410

  11. A Statistical Learning Framework for Materials Science: Application to Elastic Moduli of k-nary Inorganic Polycrystalline Compounds.

    Science.gov (United States)

    de Jong, Maarten; Chen, Wei; Notestine, Randy; Persson, Kristin; Ceder, Gerbrand; Jain, Anubhav; Asta, Mark; Gamst, Anthony

    2016-10-03

    Materials scientists increasingly employ machine or statistical learning (SL) techniques to accelerate materials discovery and design. Such pursuits benefit from pooling training data across, and thus being able to generalize predictions over, k-nary compounds of diverse chemistries and structures. This work presents a SL framework that addresses challenges in materials science applications, where datasets are diverse but of modest size, and extreme values are often of interest. Our advances include the application of power or Hölder means to construct descriptors that generalize over chemistry and crystal structure, and the incorporation of multivariate local regression within a gradient boosting framework. The approach is demonstrated by developing SL models to predict bulk and shear moduli (K and G, respectively) for polycrystalline inorganic compounds, using 1,940 compounds from a growing database of calculated elastic moduli for metals, semiconductors and insulators. The usefulness of the models is illustrated by screening for superhard materials.

  12. Effects of low sulfur dioxide concentrations on bioactive compounds and antioxidant properties of Aglianico red wine.

    Science.gov (United States)

    Gabriele, Morena; Gerardi, Chiara; Lucejko, Jeannette J; Longo, Vincenzo; Pucci, Laura; Domenici, Valentina

    2018-04-15

    This study analyzed the effect of low sulfur dioxide concentrations on the chromatic properties, phytochemical composition and antioxidant activity of Aglianico red wines with respect to wines produced from conventional winemaking. We determined the phytochemical composition by spectrophotometric methods and HPLC-DAD analysis and the in vitro antioxidant activity of different wine samples by the ORAC assay. The main important classes of fluorophore molecules in red wine were identified by Front-Face fluorescence spectroscopy, and the emission intensity trend was investigated at various sulfur dioxide concentrations. Lastly, we tested the effects of both conventional and low sulfite wines on ex vivo human erythrocytes under oxidative stimulus by the cellular antioxidant activity (CAA) assay and the hemolysis test. The addition of sulfur dioxide, which has well-known side effects, increased the content of certain bioactive components but did not raise the erythrocyte antioxidant capacity. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. MICROBIAL DEGRADATION OF NITROGEN, OXYGEN AND SULFUR HETEROCYCLIC COMPOUNDS UNDER ANAEROBIC CONDITIONS: STUDIES WITH AQUIFER SAMPLES

    Science.gov (United States)

    The potential for anaerobic biodegradation of 12 heterocyclic model compounds was studied. Nine of the model compounds were biotransformed in aquifer slurries under sulfate-reducing or methanogenic conditions. The nitrogen and oxygen heterocyclic compounds were more susceptible t...

  14. Creating a computer game suitable for practice of nomenclature of inorganic compounds

    OpenAIRE

    NEČEDA, Luboš

    2017-01-01

    This thesis is focused on usage of computer game (adventure game) in teaching of chemismy (posted on internet since 2017). Game is situated to the town of České Budějovice and contains set of tests from Inorganic chemisty. This game can be used to motivate students to study chemistry on primary schools.

  15. Facilitated and selective oxidation of thiophenic sulfur compounds using MoOx/Al₂O₃-H₂O₂ system under ultrasonic irradiation.

    Science.gov (United States)

    Akbari, Azam; Omidkhah, Mohammadreza; Towfighi Darian, Jafar

    2015-03-01

    Oxidative desulfurization of thiophenic sulfur compounds of benzothiophene (BT), dibenzothiophene (DBT) and 4,6-dimethyl dibenzothiophene (4,6-DMDBT) with MoOx/Al₂O₃ catalyst and H₂O₂ oxidant has been facilitated and more selective under ultrasonic irradiation. The catalyst with the optimum 10% of Mo loading consisted of isolated tetrahedral molybdenum oxide species based on FTIR analysis. The increase of Mo loading to 15% and 20% caused to generation of polymolybdate and MoO₃ crystals which decreased desulfurization activity. Sonication enhanced the apparent reaction rate constants in oxidation of all three sulfur compounds. An increase in the Arrhenius factor (A0), which is the total number of collisions per second, could explain the acceleration in the rate constants by sonication. The apparent activated energy (Ea) of BT oxidation was reduced from 96.6 to 75.3 kJ/mol by using ultrasound. This indicated that ultrasound had also a chemical effect, like a catalytic influence, in the acceleration of BT removal. DBT oxidation was reduced when investigated in the presence of tetralin, naphthalene and 2-methyl naphthalene as the model aromatic compounds of actual light oils. A higher selectivity toward DBT elimination in the presence of aromatics was obtained by sonication when compared with the silent treatment. Ultrasound cleaned the catalyst surface from adsorbed aromatics. On the basis of the obtained results, a mechanistic proposal for this desulfurization was explained. Oxidation was performed by nucleophilic attack of sulfur atom to the molybdenum peroxide species of tetrahedral molybdates, which was more advanced by sonication. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Mixing-assisted oxidative desulfurization of model sulfur compounds using polyoxometalate/H2O2 catalytic system

    OpenAIRE

    Angelo Earvin Sy Choi; Susan Roces; Nathaniel Dugos; Meng-Wei Wan

    2016-01-01

    Desulfurization of fossil fuel derived oil is needed in order to comply with environmental regulations. Dibenzothiophene and benzothiophene are among the predominant sulfur compound present in raw diesel oil. In this study, mixing-assisted oxidative desulfurization of dibenzothiophene and benzothiophene were carried out using polyoxometalate/H2O2 systems and a phase transfer agent. The effects of reaction time (2–30 min) and temperature (30–70 °C) were examined in the oxidation of model sulfu...

  17. Current emission trends for nitrogen oxides, sulfur dioxide, and volatile organic compounds by month and state: Methodology and results

    International Nuclear Information System (INIS)

    Kohout, E.J.; Miller, D.J.; Nieves, L.A.; Rothman, D.S.; Saricks, C.L.; Stodolsky, F.; Hanson, D.A.

    1990-08-01

    This report presents estimates of monthly sulfur dioxide (SO 2 ), nitrogen oxides (NO x ), and nonmethane voltatile organic compound (VOC) emissions by sector, region, and state in the contiguous United States for the years 1975 through 1988. This work has been funded as part of the National Acid Precipitation Assessment Program's Emissions and Controls Task Group by the US Department of Energy (DOE) Office of Fossil Energy (FE). The DOE project officer is Edward C. Trexler, DOE/FE Office of Planning and Environment

  18. Influence of zinc oxide during different stages of sulfur vulcanization. Elucidated by model compound studies

    NARCIS (Netherlands)

    Heideman, G.; Datta, Rabin; Noordermeer, Jacobus W.M.; van Baarle, B.

    2005-01-01

    The addition of zinc oxide (ZnO) as an activator for the sulfur vulcanization of rubbers enhances the vulcanization efficiency and vulcanizate properties and reduces the vulcanization time. The first part of this article deals with the reduction and optimization of the amount of ZnO. Two different

  19. Stimulation of rhamnolipid biosurfactants production in Pseudomonas aeruginosa AK6U by organosulfur compounds provided as sulfur sources.

    Science.gov (United States)

    Ismail, Wael; Shammary, Sultanah Al; El-Sayed, Wael S; Obuekwe, Christian; El Nayal, Ashraf M; Abdul Raheem, Abdul Salam; Al-Humam, Abdulmohsen

    2015-09-01

    A Pseudomonas aeruginosa AK6U strain produced rhamnolipid biosurfactants to variable extents when grown on MgSO 4 or organosulfur compounds as sulfur sources and glucose as a carbon source. Organosulfur cultures produced much higher biosurfactants amounts compared to the MgSO 4 cultures. The surface tension of the growth medium was reduced from 72 mN/m to 54 and 30 mN/m in cultures containing MgSO 4 and 4,6-dimethyldibenzothiophene (4,6-DM-DBT), respectively. AK6U cultures produced different rhamnolipid congener profiles depending on the provided sulfur source. The dibenzothiophene (DBT) culture produced more diverse and a higher number of rhamnolipid congeners as compared to the DBT-sulfone and MgSO 4 cultures. The number of mono-rhamnolipid congeners in the DBT culture was also higher than that detected in the DBT-sulfone and MgSO 4 cultures. Di-rhamnolipids dominated the congener profiles in all the analyzed cultures. The sulfur source can have a profound impact on the quality and quantity of the produced biosurfactants.

  20. Bonding in Sulfur-Oxygen Compounds-HSO/SOH and SOO/OSO: An Example of Recoupled Pair π Bonding.

    Science.gov (United States)

    Lindquist, Beth A; Takeshita, Tyler Y; Woon, David E; Dunning, Thom H

    2013-10-08

    The ground states (X(2)A″) of HSO and SOH are extremely close in energy, yet their molecular structures differ dramatically, e.g., re(SO) is 1.485 Å in HSO and 1.632 Å in SOH. The SO bond is also much stronger in HSO than in SOH: 100.3 kcal/mol versus 78.8 kcal/mol [RCCSD(T)-F12/AVTZ]. Similar differences are found in the SO2 isomers, SOO and OSO, depending on whether the second oxygen atom binds to oxygen or sulfur. We report generalized valence bond and RCCSD(T)-F12 calculations on HSO/SOH and OSO/SOO and analyze the bonding in all four species. We find that HSO has a shorter and stronger SO bond than SOH due to the presence of a recoupled pair bond in the π(a″) system of HSO. Similarly, the bonding in SOO and OSO differs greatly. SOO is like ozone and has substantial diradical character, while OSO has two recoupled pair π bonds and negligible diradical character. The ability of the sulfur atom to form recoupled pair bonds provides a natural explanation for the dramatic variation in the bonding in these and many other sulfur-oxygen compounds.

  1. Stimulation of rhamnolipid biosurfactants production in Pseudomonas aeruginosa AK6U by organosulfur compounds provided as sulfur sources

    Directory of Open Access Journals (Sweden)

    Wael Ismail

    2015-09-01

    Full Text Available A Pseudomonas aeruginosa AK6U strain produced rhamnolipid biosurfactants to variable extents when grown on MgSO4 or organosulfur compounds as sulfur sources and glucose as a carbon source. Organosulfur cultures produced much higher biosurfactants amounts compared to the MgSO4 cultures. The surface tension of the growth medium was reduced from 72 mN/m to 54 and 30 mN/m in cultures containing MgSO4 and 4,6-dimethyldibenzothiophene (4,6-DM-DBT, respectively. AK6U cultures produced different rhamnolipid congener profiles depending on the provided sulfur source. The dibenzothiophene (DBT culture produced more diverse and a higher number of rhamnolipid congeners as compared to the DBT-sulfone and MgSO4 cultures. The number of mono-rhamnolipid congeners in the DBT culture was also higher than that detected in the DBT-sulfone and MgSO4 cultures. Di-rhamnolipids dominated the congener profiles in all the analyzed cultures. The sulfur source can have a profound impact on the quality and quantity of the produced biosurfactants.

  2. Quantitative analysis of sulfur forms of coal and the pyrolysis behavior of sulfur compounds; Sekitanchu no io kagobutsu no keitaibetsu gan`yuryo no teiryo to sono netsubunkai kyodo

    Energy Technology Data Exchange (ETDEWEB)

    Mae, K.; Miura, K.; Shimada, M. [Kyoto University, Kyoto (Japan). Faculty of Engineering

    1996-10-28

    As part of the studies on coal utilization basics, considerations were given on quantification of sulfur forms of coal and the pyrolysis behavior of sulfur compounds. With the temperature raising oxidation method, a thermo-balance was connected directly to a mass analyzer, and the coal temperature was raised at a rate of 5{degree}C per minute and gasified. Peak division was performed on SO2 and COS production to derive sulfur forms of coal. Using the slow-speed pyrolysis method, production rates of H2S, COS, SO2 and mercaptans were measured at a temperature raising rate of 20{degree}C per minute. Sulfur content in char was also measured. With the quick pyrolysis method, a Curie point pyrolyzer was connected directly to a gas chromatograph, by which secondary reaction is suppressed, and initial pyrolytic behavior can be tracked. All kinds of coals produce a considerable amount of SO2 in the slow-speed pyrolysis, but very little in the quick pyrolysis. Instead, H2S and mercaptans are produced. Sulfur compound producing mechanisms vary depending on the temperature raising rates. By using a parallel primary reaction model, analysis was made on reactions of H2S production based on different activation energies, such as those generated from pyrite decomposition and organic sulfur decomposition. The analytic result agreed also with that from the temperature raising oxidation method. 4 refs., 6 figs., 1 tab.

  3. [Analysis of volatile sulfur compounds production of oral cavity in preschool children and influencing factors].

    Science.gov (United States)

    Zhang, Qun; Liu, Xue-nan; Chang, Qing; Ao, Shuang; Zheng, Shu-guo; Xu, Tao

    2015-12-18

    To investigate the prevalence of volatile sulfur compounds(VSC) in oral cavity of preschool children, and to analyze related factors, thus to provide scientific basis for the prediction and treatment of halitosis. The VSC content (hydrogen sulfide, methyl mercaptan, dimethyl sulfide) of 170 preschool children (4 to 6 years old) was detected by a portable gas chromatograph OralChromaTM. The status of the oral health was evaluated. The living habits and other aspects were obtained through questionnaires from the children's parents. A soft package for social statistics version 13.0 (SPSS 13.0) was used in which univariate analysis and multivariate analysis were utilized to analyze the related factors of halitosis in children. In the study, 34.4% of the total subjects had excessive VSC. Hydrogen sulfide (H₂S) [(1.59 ± 2.41) ng/10 mL] and total VSC concentration [(2.14 ± 4.42) ng/10 mL] in the girls were significantly higher (P<0.05) than those in the boys. The tongue coating score had a significant positive correlation with H2S [tongue coating area (1.68 ± 2.48) ng/10 mL,tongue coating thickness (2.18 ± 2.69) ng/10 mL] and total VSC concentration [tongue coating area, (2.26 ± 4.31) ng/10 mL,tongue coating thickness (2.41 ± 3.02) ng/10 mL , P<0.01]. The site number of DI-S ≥ 2 had a significant positive correlation with methyl mercaptan (CH3SH) and dimethyl sulfide [(CH3)2S] concentration (P<0.01). The concentration of H₂S [(1.19 ± 1.62) ng/10 mL] in children, whose mother had a higher degree of education, was statistically lower (P<0.01). The children who took dessert or sweat drinks more frequently had lower H2S [(1.04 ± 1.55) ng/10 mL, P<0.05] concentration, while CH3SH and (CH3₂)S concentration [(0.29 ± 1.92) ng/10 mL, (0.37 ± 2.06) ng/10 mL, P<0.05) were higher in the children with mouth-breath habit. A high prevalence of halitosis was noted in preschool children. Gender, tongue coating index, debris index-simplified, status of the mother

  4. Characterization of inorganic compounds in nutritional supplements by the instrumental neutron activation analysis

    International Nuclear Information System (INIS)

    Nardi, Daniela T.; Saiki, Mitiko; Vasconcellos, Maria B.A.

    2000-01-01

    In this work instrumental neutron activation analysis was applied in the analyses of samples of nutritional supplements in order to evaluate the composition of their essential inorganic components. Results obtained in these analyses presented, in general, a good agreement with the label values. Precision and accuracy of the results were also evaluated by analyzing NIST 2704 Buffalo River Sediment and NIST 1400 Bone Ash reference materials. (author)

  5. Stratification and the distribution of phytoplankton, nutrients, inorganic carbon, and sulfur in the surface waters of Weddell Sea leads

    NARCIS (Netherlands)

    Zemmelink, H. J.; Houghton, L.; Dacey, J. W. H.; Stefels, J.; Koch, B. P.; Wisotzki, A.; Scheltz, A.; Thomas, D. N.; Papadimitriou, S.; Kennedy, H.; Kuosa, H.; Dittmar, T.

    2008-01-01

    The distribution (fine resolution depth profiles) of major nutrients, chlorophyll-a, organic compounds, and phytoplankton (biomass and numbers) was examined in lead water in pack ice of the Weddell Sea. Samples were taken by pulling water into a syringe from a series of depths from 0.002 to 4m.

  6. Crystal structure of caesium hydrogen (L)-aspartate and an overview of crystalline compounds of aspartic acid with inorganic constituents

    Energy Technology Data Exchange (ETDEWEB)

    Fleck, M. [Universitaet Wien (Austria). Institut fuer Mineralogie und Kristallographie; Emmerich, R.; Bohaty, L. [Universitaet zu Koeln (Austria). Institut fuer Kristallographie

    2010-08-15

    The crystal structure of the new polar compound caesium hydrogen (L)-aspartate, Cs(C{sub 4}H{sub 6}NO{sub 4}), (abbreviated: Cs(L -AspH)) was determined from single crystal X-ray diffraction data; it comprises two crystallographically different L -AspH anions that are connected via caesium cations to form a three dimensional framework. The Cs ions are irregularly sevenfold[Cs1O{sub 7}] respectively eightfold[Cs2O{sub 8}] coordinated to all {alpha}- and {beta}- carboxylate oxygen atoms. Cs(L -AspH) represents a novel structure type of its own, as do most compounds of (L)-aspartic acid with inorganic constituents. A brief summary of such structurally known aspartates is given. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  7. Solvent extraction of aromatic sulfur compounds from n-heptane using the 1-ethyl-3-methylimidazolium tricyanomethanide ionic liquid

    International Nuclear Information System (INIS)

    Królikowski, Marek; Walczak, Klaudia; Domańska, Urszula

    2013-01-01

    Highlights: • LLE data for (EMIMTCM + thiophene/benzothiophene + n-heptane) were determined. • High S and β for the extraction of thiophene/benzothiophene from n-heptane was found. • Results of S and β were compared with available literature. • The NRTL model satisfactorily correlates the LLE data. -- Abstract: The ionic liquid 1-ethyl-3-methylimidazolium tricyanomethanide ([EMIM][TCM]) has been tested as a solvent for the separation of sulfur compounds from aliphatic hydrocarbon. Liquid–liquid phase equilibrium data have been determined for ternary systems containing the ionic liquid, thiophene or benzothiophene and n-heptane. The influence of temperature on the separation of thiophene from n-heptane was determined. High solubility of sulfur compounds and practical immiscibility of aliphatic hydrocarbon in ionic liquid have been found. The values of selectivity and solute distribution ratios have been calculated for all systems and compared with literature data for other 1-ethyl-3-methylimidazolium-based ionic liquids. High values of selectivity were obtained. The experimental data were correlated using the NRTL equation, and the binary interaction parameters have been reported. The phase equilibria diagrams for the ternary mixtures including the experimental and calculated tie-lines have been presented

  8. Mixing-assisted oxidative desulfurization of model sulfur compounds using polyoxometalate/H2O2 catalytic system

    Directory of Open Access Journals (Sweden)

    Angelo Earvin Sy Choi

    2016-07-01

    Full Text Available Desulfurization of fossil fuel derived oil is needed in order to comply with environmental regulations. Dibenzothiophene and benzothiophene are among the predominant sulfur compound present in raw diesel oil. In this study, mixing-assisted oxidative desulfurization of dibenzothiophene and benzothiophene were carried out using polyoxometalate/H2O2 systems and a phase transfer agent. The effects of reaction time (2–30 min and temperature (30–70 °C were examined in the oxidation of model sulfur compounds mixed in toluene. A pseudo first-order reaction kinetic model and the Arrhenius equation were utilized in order to evaluate the kinetic rate constant and activation energy of each catalyst tested in the desulfurization process. Results showed the order of catalytic activity and activation energy of the different polyoxometalate catalysts to be H3PW12O40 > H3PM12O40 > H4SiW12O40 for both dibenzothiophene and benzothiophene.

  9. Peatland Acidobacteria with a dissimilatory sulfur metabolism.

    Science.gov (United States)

    Hausmann, Bela; Pelikan, Claus; Herbold, Craig W; Köstlbacher, Stephan; Albertsen, Mads; Eichorst, Stephanie A; Glavina Del Rio, Tijana; Huemer, Martin; Nielsen, Per H; Rattei, Thomas; Stingl, Ulrich; Tringe, Susannah G; Trojan, Daniela; Wentrup, Cecilia; Woebken, Dagmar; Pester, Michael; Loy, Alexander

    2018-02-23

    Sulfur-cycling microorganisms impact organic matter decomposition in wetlands and consequently greenhouse gas emissions from these globally relevant environments. However, their identities and physiological properties are largely unknown. By applying a functional metagenomics approach to an acidic peatland, we recovered draft genomes of seven novel Acidobacteria species with the potential for dissimilatory sulfite (dsrAB, dsrC, dsrD, dsrN, dsrT, dsrMKJOP) or sulfate respiration (sat, aprBA, qmoABC plus dsr genes). Surprisingly, the genomes also encoded DsrL, which so far was only found in sulfur-oxidizing microorganisms. Metatranscriptome analysis demonstrated expression of acidobacterial sulfur-metabolism genes in native peat soil and their upregulation in diverse anoxic microcosms. This indicated an active sulfate respiration pathway, which, however, might also operate in reverse for dissimilatory sulfur oxidation or disproportionation as proposed for the sulfur-oxidizing Desulfurivibrio alkaliphilus. Acidobacteria that only harbored genes for sulfite reduction additionally encoded enzymes that liberate sulfite from organosulfonates, which suggested organic sulfur compounds as complementary energy sources. Further metabolic potentials included polysaccharide hydrolysis and sugar utilization, aerobic respiration, several fermentative capabilities, and hydrogen oxidation. Our findings extend both, the known physiological and genetic properties of Acidobacteria and the known taxonomic diversity of microorganisms with a DsrAB-based sulfur metabolism, and highlight new fundamental niches for facultative anaerobic Acidobacteria in wetlands based on exploitation of inorganic and organic sulfur molecules for energy conservation.

  10. A Liquid Inorganic Electrolyte Showing an Unusually High Lithium Ion Transference Number: A Concentrated Solution of LiAlCl4 in Sulfur Dioxide

    Directory of Open Access Journals (Sweden)

    Martin Winter

    2013-08-01

    Full Text Available We report on studies of an inorganic electrolyte: LiAlCl4 in liquid sulfur dioxide. Concentrated solutions show a very high conductivity when compared with typical electrolytes for lithium ion batteries that are based on organic solvents. Our investigations include conductivity measurements and measurements of transference numbers via nuclear magnetic resonance (NMR and by a classical direct method, Hittorf’s method. For the use of Hittorf’s method, it is necessary to measure the concentration of the electrolyte in a selected cell compartment before and after electrochemical polarization very precisely. This task was finally performed by potentiometric titration after hydrolysis of the salt. The Haven ratio was determined to estimate the association behavior of this very concentrated electrolyte solution. The measured unusually high transference number of the lithium cation of the studied most concentrated solution, a molten solvate LiAlCl4 × 1.6SO2, makes this electrolyte a promising alternative for lithium ion cells with high power ability.

  11. Bioprocesses for the Removal of Volatile Sulfur Compounds from Gas Streams

    NARCIS (Netherlands)

    Janssen, A.J.H.; bosch, van den P.L.M.; Leerdam, van R.C.; Graaff, de C.M.

    2013-01-01

    This chapter describes the biological removal of sulphur compounds from gas streams. First, an overview is given of the toxicity of sulphur compounds to animals and humans whereafter biological and industrial formation routes for (organic) sulphur compounds are given. Microbial degradation routes of

  12. Hibiscus Rosa Sinensis Leaves: Analysis Of Proximate, Antioxidant Activities And Inorganic Compound

    International Nuclear Information System (INIS)

    Saiful Irwan Zubairi; Nurul Shahreda Jaies

    2014-01-01

    A variety of herbal plants species has been used in traditional medicine. Most of these plants contained several potent bio-active ingredients and nutrients that could give potential positive effects to the health such as antioxidant and antipyretic. Hibiscus rosa sinensis, commonly known as Bunga raya, have similar concoction characteristic to tea which contain antioxidants that help to control cholesterol. In addition, mucilage that was found in the leaves could helps to reduce extreme body heat during fever (which potentially acts as an antipyretic). Therefore, this preliminary study on the fresh and dried H. rosa sinensis leaves was carried out to analyze and identify the nutrients content, anti-oxidants and inorganic material. Total phenolic content (TPC) method was used for both fresh and dried leaves prior to the antioxidant activities of DPPH free radicals scavenging and ferric ion reducing antioxidant power (FRAP) as to confirm the existence of antioxidant constituents. Meanwhile, the composition of heavy metals was studied using inductively coupled plasma mass spectrometry (ICP-MS). The proximate analysis of the fresh leaves showed the presence of moisture content (9.03 %), protein (10.44 %), fat (6.43 %), crude fiber (11.55 %), ash (11.22 %) and carbohydrate (51.33 %). Meanwhile, the inorganic contents are as follows: cadmium (Cd), chromium (Cr), arsenic (As), nickel (Ni), lead (Pb), iron (Fe) and zinc (Zn). Furthermore, the antioxidant activities of FRAP and DPPH showed that dried leaves of H. rosa sinensis was higher than the fresh leaves (p < 0.05) irrespective of any solvent used. The positive correlation between TPC and two other antioxidant activities of DPPH and FRAP (p < 0.05) indicates the presence of antioxidant components in the acetone and water extracts. Therefore, the high availability of essential nutritional component, anti-oxidants and low concentration of hazardous inorganic matter in H. rosa sinensis leaves enable it to be used as one

  13. Biodegradation of Various Aromatic Compounds by Enriched Bacterial Cultures: Part B--Nitrogen-, Sulfur-, and Oxygen-Containing Heterocyclic Aromatic Compounds.

    Science.gov (United States)

    Oberoi, Akashdeep Singh; Philip, Ligy; Bhallamudi, S Murty

    2015-07-01

    Present study focused on the biodegradation of various heterocyclic nitrogen, sulfur, and oxygen (NSO) compounds using naphthalene-enriched culture. Target compounds in the study were pyridine, quinoline, benzothiophene, and benzofuran. Screening studies were carried out using different microbial consortia enriched with specific polycyclic aromatic hydrocarbon (PAH) and NSO compounds. Among different microbial consortia, naphthalene-enriched culture was the most efficient consortium based on high substrate degradation rate. Substrate degradation rate with naphthalene-enriched culture followed the order pyridine > quinoline > benzofuran > benzothiophene. Benzothiophene and benzofuran were found to be highly recalcitrant pollutants. Benzothiophene could not be biodegraded when concentration was above 50 mg/l. It was observed that 2-(1H)-quinolinone, benzothiophene-2-one, and benzofuran-2,3-dione were formed as metabolic intermediates during biodegradation of quinoline, benzothiophene, and benzofuran, respectively. Quinoline-N and pyridine-N were transformed into free ammonium ions during the biodegradation process. Biodegradation pathways for various NSO compounds are proposed. Monod inhibition model was able to simulate single substrate biodegradation kinetics satisfactorily. Benzothiophene and benzofuran biodegradation kinetics, in presence of acetone, was simulated using a generalized multi-substrate model.

  14. Hygroscopic growth and critical supersaturations for mixed aerosol particles of inorganic and organic compounds of atmospheric relevance

    Directory of Open Access Journals (Sweden)

    B. Svenningsson

    2006-01-01

    Full Text Available The organic fraction of atmospheric aerosols contains a multitude of compounds and usually only a small fraction can be identified and quantified. However, a limited number of representative organic compounds can be used to describe the water-soluble organic fraction. In this work, initiated within the EU 5FP project SMOCC, four mixtures containing various amounts of inorganic salts (ammonium sulfate, ammonium nitrate, and sodium chloride and three model organic compounds (levoglucosan, succinic acid and fulvic acid were studied. The interaction between water vapor and aerosol particles was studied at different relative humidities: at subsaturation using a hygroscopic tandem differential mobility analyzer (H-TDMA and at supersaturation using a cloud condensation nuclei spectrometer (CCN spectrometer. Surface tensions as a function of carbon concentrations were measured using a bubble tensiometer. Parameterizations of water activity as a function of molality, based on hygroscopic growth, are given for the pure organic compounds and for the mixtures, indicating van't Hoff factors around 1 for the organics. The Zdanovskii-Stokes-Robinson (ZSR mixing rule was tested on the hygroscopic growth of the mixtures and it was found to adequately explain the hygroscopic growth for 3 out of 4 mixtures, when the limited solubility of succinic acid is taken into account. One mixture containing sodium chloride was studied and showed a pronounced deviation from the ZSR mixing rule. Critical supersaturations calculated using the parameterizations of water activity and the measured surface tensions were compared with those determined experimentally.

  15. [Pollution characteristics and source of the atmospheric fine particles and secondary inorganic compounds at Mount Dinghu in autumn season].

    Science.gov (United States)

    Liu, Zi-Rui; Wang, Yue-Si; Liu, Quan; Liu, Lu-Ning; Zhang, De-Qiang

    2011-11-01

    Real-time measurements of PM2.5, secondary inorganic compounds in PM2.5 (SO4(2-), NH4(+), and NO3(-)) and related gaseous pollutants were conducted at Mount Dinghu, a regional background station of the Pearl River Delta (PRD), in October and November 2008 by using a conventional R&P TEOM and a system of rapid collection of fine particles and ion chromatography (RCFP-IC). Sources and transportation of atmospheric particles during the experiment were discussed with principal component analysis and backward trajectories calculated using HYSPLIT model. The average daily mass concentrations of PM2.5 were 76.9 microg x m(-3) during sampling period, and average daily mass concentrations of SO4(2-), NH4(+), and NO3(-) were 20.0 microg x m(-3), 6.8 microg x m(-3) and 2.6 microg x m(-3), respectively. The sum of these three secondary inorganic compounds accounted for more than one third of the PM2.5 mass concentration, which had become the major source of atmospheric fine particles at Mount Dinghu. The diurnal variation of PM2.5, SO4(2-), and NH4(+) all showed a "bimodal" distribution with two peaks appeared at 10:00 am and at 16:00 pm, respectively, whereas NO3(-s) howed "single peak" distribution peaked at 10:00 am. The mass concentrations of SO4(2-) in PM2.5 had the similar diurnal variation with that of SO2, SO4(2-) in PM2.5 was mainly transformed from SO2, whereas NO3(-) showed difference diurnal variation with that of NO2, and the second conversion rate of NO2 was far lower than that of SO2. NH4(+) in PM2.5 existed mainly in the form of sulfate, nitrate and chloride. Both of principal component analysis and back trajectory analysis showed that the variations of PM2.5 and secondary inorganic compounds at Mount Dinghu were mainly affected by the long-range transport air mass passed over Guangzhou, Huizhou and other highly industrialized areas which carried air pollutants to the observation site, at the same time local sulfate originated from secondary formation also

  16. Composition and leaching of construction and demolition waste: Inorganic elements and organic compounds

    DEFF Research Database (Denmark)

    Butera, Stefania; Christensen, Thomas Højlund; Astrup, Thomas Fruergaard

    2014-01-01

    Thirty-three samples of construction and demolition waste collected at 11 recycling facilities in Denmark were characterised in terms of total content and leaching of inorganic elements and presence of the persistent organic pollutants PCBs and PAHs. Samples included (i) "clean" (i.e. unmixed...... for leaching, was observed indicating that the number of analysed samples may be critical in relation to decisions regarding management and utilisation of the materials. Higher leaching of chromium, sulphate and chloride were observed for masonry-containing and partly carbonated samples, indicating that source...... segregation and management practices may be important. Generally, leaching was in compliance with available leaching limits, except for selenium, and in some cases chromium, sulphate and antimony. © 2014 Elsevier B.V....

  17. Antibacterial and antifungal activity of sulfur-containing compounds from Petiveria alliacea L.

    Science.gov (United States)

    Kim, Seokwon; Kubec, Roman; Musah, Rabi A

    2006-03-08

    A total of 18 organosulfur compounds originating from Petiveria alliacea L. roots have been tested for their antibacterial and antifungal activities. These represent compounds occurring in fresh homogenates as well as those present in various macerates, extracts and other preparations made from Petiveria alliacea. Of the compounds assayed, the thiosulfinates, trisulfides and benzylsulfinic acid were observed to be the most active, with the benzyl-containing thiosulfinates exhibiting the broadest spectrum of antimicrobial activity. The effect of plant sample preparation conditions on the antimicrobial activity of the extract is discussed.

  18. Critical review of the chemistry and thermodynamics of technetium and some of its inorganic compounds and aqueous species

    International Nuclear Information System (INIS)

    Rard, J.A.

    1983-01-01

    Chemical and thermodynamic data for Technetium (Tc) and some of its inorganic compounds and aqueous species are reviewed here. Major emphasis is given to systems with potential geochemical applications, especially the geochemistry of radioactive waste disposal. Compounds considered include oxides, hydroxides, hydrates oxides, halides, oxyhalides, double halides, and sulfides. The aqueous species considered include those in both noncomplexing media (pertechnetates, technetates, aquo-ions, and hydrolyzed cations) and complexing media (halides, sulfates, and phosphates). Thermodynamic values are recommended for specific compounds and aqueous ions when reliable experimental data are available. Where thermodynamic data are inadequate or unavailable, the chemistry is still discussed to provide information about what needs to be measured, and which chemistry needs to be clarified. A major application of these thermodynamic data will be for chemical equilibrium modeling and for construction of potential-pH diagrams for aqueous solutions. Unfortunately, the present lack of data precludes such calculations for complexing aqueous media. The situation is much better for noncomplexing aqueous media, but the chemistry and thermodynamics of cationic Tc(V) species and hydrolyzed Tc(III) species are poorly understood. 240 references, 6 tables

  19. Release of Extracellular Polymeric Substance and Disintegration of Anaerobic Granular Sludge under Reduced Sulfur Compounds-Rich Conditions

    Directory of Open Access Journals (Sweden)

    Takuro Kobayashi

    2015-07-01

    Full Text Available The effect of reduced form of sulfur compounds on granular sludge was investigated. Significant release of extracellular polymeric substance (EPS from the granular sludge occurred in the presence of sulfide and methanethiol according to various concentrations. Granular sludge also showed a rapid increase in turbidity and decrease in diameter in accordance with sulfide concentration during the long-term shaking, suggesting that the strength of the granules was reduced with high-concentration sulfide. A continuous experiment of up-flow anaerobic sludge blanket reactors with different concentrations of sulfide (10, 200, 500 mg-S/L influence demonstrated that the reactor fed with higher concentration of sulfide allowed more washout of small particle-suspended solid (SS content and soluble carbohydrate and protein, which were considered as EPS released from biofilm. Finally, the presence of sulfide negatively affected methane production, chemical oxygen demand removal and sludge retention in operational performance.

  20. Inorganic insertion compounds under the form of Langmuir-Blodgett films

    International Nuclear Information System (INIS)

    Zylberajch, Claire

    1989-01-01

    As the study of organic or mineral compounds under the form of thin layers showed that they are displaying very original properties with respect to massive compounds, this research thesis reports a work which aimed at obtaining mineral conductive materials under the form of extremely thin layers, notably metallic sulfides of mercury and cadmium. Synthesis is performed in soft conditions within an organic matrix produced by using the Langmuir-Blodgett technique with successive diffusions of mineral reactants. Salt formation is monitored by infrared spectroscopy. Physical properties of these compounds have been studied by various techniques (UV, visible, and IR spectroscopy, linear dichroism, X ray diffraction, X ray photoelectron spectrometry, conduction, and so on). Structural and electronic properties of these extremely thin films confirm that metallic sulfides adopt a lamellar geometry with molecular thickness. Conductivity and photo-conductivity are interpreted by means of a conventional band diagram [fr

  1. Composition and leaching of construction and demolition waste: inorganic elements and organic compounds.

    Science.gov (United States)

    Butera, Stefania; Christensen, Thomas H; Astrup, Thomas F

    2014-07-15

    Thirty-three samples of construction and demolition waste collected at 11 recycling facilities in Denmark were characterised in terms of total content and leaching of inorganic elements and presence of the persistent organic pollutants PCBs and PAHs. Samples included (i) "clean" (i.e. unmixed) concrete waste, (ii) mixed masonry and concrete, (iii) asphalt and (iv) freshly cast concrete cores; both old and newly generated construction and demolition waste was included. PCBs and PAHs were detected in all samples, generally in non-critical concentrations. Overall, PAHs were comparable to background levels in urban environments. "Old" and "new" concrete samples indicated different PCB congener profiles and the presence of PCB even in new concrete suggested that background levels in raw materials may be an issue. Significant variability in total content of trace elements, even more pronounced for leaching, was observed indicating that the number of analysed samples may be critical in relation to decisions regarding management and utilisation of the materials. Higher leaching of chromium, sulphate and chloride were observed for masonry-containing and partly carbonated samples, indicating that source segregation and management practices may be important. Generally, leaching was in compliance with available leaching limits, except for selenium, and in some cases chromium, sulphate and antimony. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Production of volatile and sulfur compounds by ten Saccharomyces cerevisiae strains inoculated in Trebbiano must

    Directory of Open Access Journals (Sweden)

    Francesca ePatrignani

    2016-03-01

    Full Text Available In wines, the presence of sulphur compounds is the resulting of several contributions among which yeast metabolism. The characterization of the starter Saccharomyces cerevisiae needs to be performed also taking into account this ability even if evaluated together with the overall metabolic profile. In this perspective, principal aim of this experimental research was the evaluation of the volatile profiles, throughout GC/MS technique coupled with solid phase micro extraction, of wines obtained throughout the fermentation of 10 strains of Saccharomyces cerevisiae. In addition, the production of sulphur compounds was further evaluated by using a gas-chromatograph coupled with a Flame Photometric Detector. Specifically, the ten strains were inoculated in Trebbiano musts and the fermentations were monitored for 19 days. In the produced wines, volatile and sulphur compounds as well as amino acid concentrations were investigated. Also the physico-chemical characteristics of the wines and their electronic nose profiles were evaluated.

  3. Cu-based metal–organic framework/activated carbon composites for sulfur compounds removal

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Rui-Hua [State Key Laboratory of Coal Science and Technology, Co-founded by Shanxi Province and the Ministry of Science and Technology, Institute for Chemical Engineering of Coal, Taiyuan University of Technology, West Yingze Street Number 79, Taiyuan 030024 (China); Zhang, Zhen-Rong [Institute of Applied Chemical, Shanxi (China); Fan, Hui-Ling, E-mail: fanhuiling@tyut.edu.cn [State Key Laboratory of Coal Science and Technology, Co-founded by Shanxi Province and the Ministry of Science and Technology, Institute for Chemical Engineering of Coal, Taiyuan University of Technology, West Yingze Street Number 79, Taiyuan 030024 (China); Zhen, Tian [Deparment of Analysis and Service Center Micromertics instrumental Ltd, Shanghai (China); Shangguan, Ju; Mi, Jie [State Key Laboratory of Coal Science and Technology, Co-founded by Shanxi Province and the Ministry of Science and Technology, Institute for Chemical Engineering of Coal, Taiyuan University of Technology, West Yingze Street Number 79, Taiyuan 030024 (China)

    2017-02-01

    Highlights: • Incorporation of AC less than 2% in MOF-199 can increase micropores and BET surface area, as evidenced by N{sub 2} adsorption. • Lewis acid (unsaturated copper) sites could also be increased in the modified MOF-199, as revealed by Py-IR characterization. • Composite with 2% AC showed highest sulfur capacity with 8.46 and 8.53% for H{sub 2}S and CH{sub 3}SCH{sub 3}, respectively. • The adsorption of CH{sub 3}SCH{sub 3} on composite is reversible, physic-adsorption and weak chemisorption were involved. - Abstract: MOF-199 was modified by incorporating activated carbon (AC) during its synthesis under hydrothermal conditions to improve its performance in the removal of hydrogen sulfide (H{sub 2}S) and dimethyl sulfide (CH{sub 3}SCH{sub 3}). A variety of different characterization techniques including X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, nitrogen adsorption/desorption isotherms, scanning electron microscopy (SEM), pyridine adsorption infrared spectroscopy (Py-IR), thermogravimetric- mass spectroscopy (TG-MS) and X-ray photoelectron spectroscopy (XPS) were used to analyze the fresh and exhausted composites. It was found that the composites, which have an amount of AC of less than 2%, had the same morphology as those of pristine MOF-199, but exhibited a more ordered crystallinity structure as well as higher surface area. The composite with 2% AC incorporation showed highest sulfur capacity of 8.46 and 8.53% for H{sub 2}S and CH{sub 3}SCH{sub 3}, respectively, which increased by 51 and 41% compared to that of MOF-199. This improvement was attributed to the formation of more micropores and especially the increased number of unsaturated copper metal sites, as revealed by Py-IR. It is suggested the chemical reaction was apparent during adsorption of H{sub 2}S, which resulted in the formation of CuS and the collapse of the MOF structure. Whereas reversible chemisorption was found for CH{sub 3}SCH{sub 3} adsorption, as

  4. A study of sulfur-containing compounds in mouth- and nose-exhaled breath and in the oral cavity using selected ion flow tube mass spectrometry

    Czech Academy of Sciences Publication Activity Database

    Pysanenko, A.; Španěl, Patrik; Smith, D.

    2008-01-01

    Roč. 2, - (2008), 046004-1-13 ISSN 1752-7155 R&D Projects: GA ČR GA202/06/0776 Institutional research plan: CEZ:AV0Z40400503 Keywords : sulfur-containing compounds * SIFT-MS Subject RIV: CF - Physical ; Theoretical Chemistry

  5. Kinetics of reaction of peroxynitrite with selenium- and sulfur-containing compounds

    DEFF Research Database (Denmark)

    Storkey, Corin; Pattison, David I.; Ignasiak, Marta T.

    2015-01-01

    with peroxynitrite with high rate constants. Low molecular mass selenols react particularly rapidly with peroxynitrite, with second order rate constants k2 in the range 5.1×105-1.9×106 M-1 s-1, and 250-830 fold faster than the corresponding thiols (RSH) and many other endogenous biological targets. Reactions......Peroxynitrite (the physiological mixture of ONOOH and its anion, ONOO-) is a powerful biologically-relevant oxidant capable of oxidizing and damaging a range of important targets including sulfides, thiols, lipids, proteins, carbohydrates and nucleic acids. Excessive production of peroxynitrite...... of peroxynitrite with selenides, including selenosugars are approximately 15-fold faster than their sulfur homologs with k2 approximately 2.5×103 M-1 s-1. The rate constants for diselenides and sulfides were slower with k2 0.72-1.3×103 M-1 s-1 and approximately 2.1×102 M-1 s-1 respectively. These studies...

  6. Variable trajectory model for regional assessments of air pollution from sulfur compounds.

    Energy Technology Data Exchange (ETDEWEB)

    Powell, D.C.; McNaughton, D.J.; Wendell, L.L.; Drake, R.L.

    1979-02-01

    This report describes a sulfur oxides atmospheric pollution model that calculates trajectories using single-layer historical wind data as well as chemical transformation and deposition following discrete contaminant air masses. Vertical diffusion under constraints is calculated, but all horizontal dispersion is a funcion of trajectory variation. The ground-level air concentrations and deposition are calculated in a rectangular area comprising the northeastern United States and southeastern Canada. Calculations for a 29-day assessment period in April 1974 are presented along with a limited verification. Results for the studies were calculated using a source inventory comprising 61% of the anthropogenic SO/sub 2/ emissions. Using current model parameterization levels, predicted concentration values are most sensitive to variations in dry deposition of SO/sub 2/, wet deposition of sulfate, and transformation of SO/sub 2/ to sulfate. Replacing the variable mixed-layer depth and variable stability features of the model with constant definitions of each results in increased ground-level concentration predicions for SO/sub 2/ and particularly for sulfate.

  7. A method for nitric oxide radical scavenging properties of sulfur containing compounds.

    NARCIS (Netherlands)

    Vriesman, M.F.; Haenen, G.R.M.M.; Westerveld, G.J.; Paquay, J.B.G.; Voss, H.P.; Bast, A.

    1997-01-01

    A new method for the quantification of the nitric oxide (NO) scavenging activity of compounds in aqueous solutions is described using an amperometric NO sensor. After correction for the spontaneous degradation of NO, second-order rate kinetics of the scavenging reaction are observed.

  8. Large-scale exfoliation of inorganic layered compounds in aqueous surfactant solutions

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Ronan J.; King, Paul J.; Lotya, Mustafa; Wirtz, Christian; Khan, Umar; De, Sukanta; O' Neill, Arlene; Coleman, Jonathan N. [School of Physics, Trinity College Dublin, Dublin 2 (Ireland); CRANN, Trinity College Dublin, Dublin 2 (Ireland); Duesberg, Georg S. [CRANN, Trinity College Dublin, Dublin 2 (Ireland); School of Chemistry, Trinity College Dublin, Dublin 2 (Ireland); Grunlan, Jaime C.; Moriarty, Gregory [Department of Mechanical Engineering, Texas A and M University, College Station, Texas 77843 (United States); Chen, Jun [Intelligent Polymer Research Institute, ARC Centre of Excellence for Electromaterials Science, AIIM Facility, University of Wollongong, NSW 2522 (Australia); Wang, Jiazhao [Institute for Superconducting and Electronic Materials, ARC Centre of Excellence for Electromaterials Science, University of Wollongong, NSW 2522 (Australia); Minett, Andrew I. [Laboratory for Sustainable Technology, School of Chemical and Biomolecular Engineering, University of Sydney, Sydney, NSW 2006 (Australia); Nicolosi, Valeria [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom)

    2011-09-08

    A method to exfoliate MoS{sub 2} in large quantities in surfactant-water solutions is described. The layered material tends to be exfoliated as dispersions of thin, relatively defect-free flakes with lateral sizes of hundreds of nanometers. This method can be extended to a range of other layered compounds. The dispersed flakes can be mixed with nanotubes or graphene to greate functional hybrid materials. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  9. Excretion of organic and inorganic tritiated compounds in cow's milk after ingestion of tritium oxide

    International Nuclear Information System (INIS)

    Van den Hoek, J.; Gerber, G.B.; Kirchmann, R.

    1980-01-01

    The secretion of tritium in milk as water, casein and lipids was studied in cows given tritiated water to drink for 25 days. The parameters of the exponential functions describing the secretion of tritium as water, casein and lipid are determined during this 'loading phase' and also for a 'decay period' of 75 days after the tritiated water administration had been terminated. Secretion started after a short delay (0.5 day). Turnover of all three compounds was short (half time of about 5 days). Calculations of the dilution of the ingested water during metabolism showed that about 83% of the milk water secreted is found to originate from drinking water; the rest comes from water in food and from that formed in metabolism. The parameters of the decay phase indicated that the principle components of water, casein and lipids had about the same turnover rates as during the loading phase. Using the loading and decay phase data, calculations were performed to determine how much activity in each compound and in each metabolic component would be excreted after a single and after a continuous application of tritium oxide when integrated over infinite times. (UK)

  10. Study of behaviour of radioactive iodine inorganic compounds in PWR type reactor loops

    International Nuclear Information System (INIS)

    Alm, M.; Johannsen, K.-H.; Dreyer, R.

    1980-01-01

    Compounds of radioactive iodine and its distribution between water and vapour depending on temperature, pressure and water regime of reactor coolant with water under pressure are investigated. The field of variation of parameters indicated is widened as compared with operating reactor parameters (pressure 2-14 MPa, temperature 210-335 deg C). Distribution of iodine compounds has been studied by a statistical method. For WWER-type reactors the following conclusions have been drawn: radioactive iodine in water and vapor in the first and second loops exists in the form of iodide, radioactive iodine concentration in water vapour at constant temperature and pressure mainly is depended on water pH value, radioactive iodine solubility in water vapor at normal parameters of the reactor first loop can be approximately calculated by the equation: Ksub(d)=Csub(g)/Csub(l)=(rhosub(g)/rhosub(l))sup(2), where Ksub(d) is a coefficient of solid distribution between water and vapour, rho is density c is concentration [ru

  11. Gene Identification and Substrate Regulation Provide Insights into Sulfur Accumulation during Bioleaching with the Psychrotolerant Acidophile Acidithiobacillus ferrivorans

    Science.gov (United States)

    Liljeqvist, Maria; Rzhepishevska, Olena I.

    2013-01-01

    The psychrotolerant acidophile Acidithiobacillus ferrivorans has been identified from cold environments and has been shown to use ferrous iron and inorganic sulfur compounds as its energy sources. A bioinformatic evaluation presented in this study suggested that Acidithiobacillus ferrivorans utilized a ferrous iron oxidation pathway similar to that of the related species Acidithiobacillus ferrooxidans. However, the inorganic sulfur oxidation pathway was less clear, since the Acidithiobacillus ferrivorans genome contained genes from both Acidithiobacillus ferrooxidans and Acidithiobacillus caldus encoding enzymes whose assigned functions are redundant. Transcriptional analysis revealed that the petA1 and petB1 genes (implicated in ferrous iron oxidation) were downregulated upon growth on the inorganic sulfur compound tetrathionate but were on average 10.5-fold upregulated in the presence of ferrous iron. In contrast, expression of cyoB1 (involved in inorganic sulfur compound oxidation) was decreased 6.6-fold upon growth on ferrous iron alone. Competition assays between ferrous iron and tetrathionate with Acidithiobacillus ferrivorans SS3 precultured on chalcopyrite mineral showed a preference for ferrous iron oxidation over tetrathionate oxidation. Also, pure and mixed cultures of psychrotolerant acidophiles were utilized for the bioleaching of metal sulfide minerals in stirred tank reactors at 5 and 25°C in order to investigate the fate of ferrous iron and inorganic sulfur compounds. Solid sulfur accumulated in bioleaching cultures growing on a chalcopyrite concentrate. Sulfur accumulation halted mineral solubilization, but sulfur was oxidized after metal release had ceased. The data indicated that ferrous iron was preferentially oxidized during growth on chalcopyrite, a finding with important implications for biomining in cold environments. PMID:23183980

  12. Insight into π-hole interactions containing the inorganic heterocyclic compounds S2N2/SN2P2.

    Science.gov (United States)

    Lu, Bo; Zhang, Xueying; Meng, Lingpeng; Zeng, Yanli

    2017-08-01

    Similar to σ-hole interactions, the π-hole interaction has attracted much attention in recent years. According to the positive electrostatic potentials above and below the surface of inorganic heterocyclic compounds S 2 N 2 and three SN 2 P 2 isomers (heterocyclic compounds 1-4), and the negative electrostatic potential outside the X atom of XH 3 (X = N, P, As), S 2 N 2 /SN 2 P 2 ⋯XH 3 (X = N, P, As) complexes were constructed and optimized at the MP2/aug-cc-pVTZ level. The X atom of XH 3 (X = N, P, As) is almost perpendicular to the ring of the heterocyclic compounds. The π-hole interaction energy becomes greater as the trend goes from 1⋯XH 3 to 4⋯XH 3 . These π-hole interactions are weak and belong to "closed-shell" noncovalent interactions. According to the energy decomposition analysis, of the three attractive terms, the dispersion energy contributes more than the electrostatic energy. The polarization effect also plays an important role in the formation of π-hole complexes, with the contrasting phenomena of decreasing electronic density in the π-hole region and increasing electric density outside the X atom of XH 3 (X = N, P, As). Graphical abstract Computed density difference plots for the complexes 3⋯NH 3 (a 1 ), 3⋯PH 3 (b 1 ), 3⋯AsH 3 (c 1 ) and electron density shifts for the complexes 3⋯NH 3 (a 2 ), 3⋯PH 3 (b 2 ),3⋯AsH 3 (c 2 ) on the 0.001 a.u. contour.

  13. The electronic structure of organic-inorganic hybrid compounds : (NH4)(2)CuCl4, (CH3NH3)(2)CuCl4 and (C2H5NH3)(2)CuCl4

    NARCIS (Netherlands)

    Zolfaghari, P.; de Wijs, G. A.; de Groot, R. A.

    2013-01-01

    Hybrid organic-inorganic compounds are an intriguing class of materials that have been experimentally studied over the past few years because of a potential broad range of applications. The electronic and magnetic properties of three organic-inorganic hybrid compounds with compositions

  14. Comparative study on the pharmacokinetics of inorganic and organic iron compounds in broiler chickens

    Directory of Open Access Journals (Sweden)

    Dimitrichka Dimitrova

    2014-03-01

    Full Text Available The pharmacokinetics of ferrous methionate and ferrous sulphate was investigated in broiler chickens after intravenous injection and crop intubation. The iron compounds were injected intravenously in v. brachialis. After 20-day “wash-out” period the ferrous methionate and ferrous sulphate were administered again by an elastic silicone tube into the crop. The serum concentrations of the iron were determined with bioanalyser. Two pharmacokinetic approaches were used – compartmental and non-compartmental analysis. After i.v. injection we found statistically significantly longer and better distribution of the iron contained in the ferrous methionate compared to the ferrous sulphate. The АUC0→∞ was statistically significantly higher in the ferrous methionate. In the alimentary tract of broiler chickens, ferrous methionate was absorbed more rapidly than ferrous sulfate. It was also distributed at a higher volume as compared to the ferrous sulfate.

  15. Evaluation of organic and inorganic compounds levels of red wines processed from Pinot Noir grapes

    Directory of Open Access Journals (Sweden)

    Heli Sirén

    2015-03-01

    The wine products showed different profiles of carbohydrates, organic acids, phenolic compounds, and minerals. Especially, saccharose (max. 0.21 g/L, rhamnose (max. 0.45 g/L, fructose (max. 1.9 g/L, and phosphate (max 1.4 g/L quantities were extremely high in some wines. The results also showed that yeast fermentation in winemaking agitated high production of lactic (max 5.7 g/L and tartaric (max 1.7 g/L acids. The red wines processed by cold maceration and natural fermentation gave similar profiles. Only one of the Pinot Noir wines entirely differentiated from the others with comparison of carbohydrates and organic acids.

  16. A crystal chemical approach to superconductivity. I. A bond-valence sum analysis of inorganic compounds

    International Nuclear Information System (INIS)

    Liebau, Friedrich; Klein, Hans-Joachim; Wang, Xiqu

    2011-01-01

    A crystal-chemical approach to superconductivity is described that is intended to complement the corresponding physical approach. The former approach takes into account the distinction between the stoichiometric valence ( stoich V) and the structural valence ( struct V) which is represented by the bond-valence sums (BVS). Through calculations of BVS values from crystal-structure data determined at ambient temperature and pressure it has been found that in chalcogenides und pnictides of the transition metals Fe, Co, Ni, Mn, Hf, and Zr the atoms of the potential superconducting units yield values of vertical stroke BVS vertical stroke = vertical stroke struct V vertical stroke ≥ 1.11 x vertical stroke stoich V vertical stroke, whereas the atoms of the charge reservoirs have in general values of vertical stroke struct V vertical stroke stoich V vertical stroke. In corresponding compounds which contain the same elements but are not becoming superconducting, nearly all atoms are found to have vertical stroke struct V vertical stroke stoich V vertical stroke. For atoms of oxocuprates that are not becoming superconducting and for atoms of the charge reservoirs of oxocuprates that become superconducting, the relation vertical stroke struct V vertical stroke stoich V vertical stroke seems also to be fulfilled, with the exception of Ba. However, in several oxocuprates the relation vertical stroke struct V vertical stroke = 1.11 x vertical stroke stoich V vertical stroke for the atoms that become superconducting units is violated. These violations seem to indicate that in oxocuprates it is the local bond-valence distribution rather than the bond-valence sums that is essential for superconductivity. The present analysis can possibly be used to predict, by a simple consideration of ambient-T, P structures, whether a compound can become an unconventional superconductor at low T, under high P and/or by doping, or not. (orig.)

  17. Organosulfate Formation through the Heterogeneous Reaction of Sulfur Dioxide with Unsaturated Compounds

    Science.gov (United States)

    George, C.; Passananti, M.; Kong, L.; Shang, J.; Perrier, S.; Jianmin, C.; Donaldson, D. J.

    2016-12-01

    The atmospheric formation of organosulfur derivatives through reaction with SO2 is generally mediated by oxidants such as O3, OH; recently we have proposed a direct reaction between SO2 and unsaturated compounds as another possible pathway for organosulfate formation in the troposphere. For the first time it was shown recently that a heterogeneous reaction between SO2 and oleic acid (OA; an unsaturated fatty acid) takes place and leads efficiently to the formation of organosulfur products. Here, we demonstrate that this reaction proceeds on various unsaturated compounds, and may therefore have a general environmental impact. We used different experimental strategies i.e., a coated flow tube (CFT), an aerosol flow tube (AFT) and a DRIFT (diffuse reflectance infrared Fourier transform) cell. The reaction products were analyzed by means of liquid chromatography coupled to a high resolution mass spectrometer (LC-HR-MS). We report indeed that SO2 reacts with large variety of C=C unsaturations and that even in the presence of ozone, SO2 reacts with OA leading to organosulfur products. A strong enhancement in product formation is observed under actinic illumination, increases the atmospheric significance of this chemical pathway. This is probably due to the chromophoric nature of the SO2 adduct with C=C bonds, and means that the contribution of this direct addition of SO2 could be in excess of 5%. The detection in atmospheric aerosols of organosulfur compounds with the same chemical formulae as the products identified here seems to confirm the importance of this reaction in the atmosphere.

  18. A method for removing sulfur bearing compounds from paraffinous hydrocarbons or a directly distilled benzine fraction

    Energy Technology Data Exchange (ETDEWEB)

    Konyukhova, T.P.; Bolotskaya, I.A.; Mikhaylova, L.A.; Sadykov, A.N.; Shitovkin, N.T.; Vlasov, V.V.

    1983-01-01

    In the known method for removing sulfurorganic compounds from paraffinous hydrocarbons or a directly distilled gasoline fraction through their adsorption using natural zeolite, in order to increase the degree of purification, clinoptilolite (Kp), which contains SiO2 and A12O3 in a molar ratio of 10.6 to 16.7 is used as the natural zeolite. The purification of the paraffinous hydrocarbons through clinoptilolite adsorption as compared with mordenite adsorption makes it possible to increase the degree of their purification of ethylmercaptane and dimethylsulfide. The effectiveness of clinoptilolite is also confirmed in removing mercaptanes and sulfides from directly distilled gasoline fractions.

  19. Reactions of the nitrate radical with a series og reduced organic sulfur-compounds in air

    DEFF Research Database (Denmark)

    JENSEN, NR; HJORTH, J; LOHSE, C

    1992-01-01

    A 480 L evacuable reaction chamber, equipped with FT-IR spectroscopy on-line and ion chromatography off-line, has been used to study the gas phase reaction between the nitrate radical, NO3, and the reduced organic sulphur compounds CH3CH2SH, (CH3CH2)2S, (CH3CH2)2S2, and CH3CH2SCH3 in air. The pro......A 480 L evacuable reaction chamber, equipped with FT-IR spectroscopy on-line and ion chromatography off-line, has been used to study the gas phase reaction between the nitrate radical, NO3, and the reduced organic sulphur compounds CH3CH2SH, (CH3CH2)2S, (CH3CH2)2S2, and CH3CH2SCH3 in air......, and CH3SSCH3 lead to the conclusion that all these species, in the reaction with the NO3 radical, follow a similar degradation mechanism producing SO2, H2SO4, R-SO3H, R-CHO, and R-CH2ONO2, as the main reaction products. The inital step of the reaction of NO3 with R-S-R and R-S- H type (R = CH3, CH2CH3...

  20. Studies on the sulfur metabolism of cows on protein-free and low-protein feed

    Directory of Open Access Journals (Sweden)

    Eino Matikkala

    1977-09-01

    Full Text Available The influence of purified, protein-free feed with urea and ammonium salts as nitrogen sources (0-feed and of non-purified, urea-rich, low-protein feeds (ULP-feed on the sulfur metabolism of cows has been studied by determining the contents of sulfur fractions in faeces, urine, milk, blood and rumen fluid. The sulfur of 0-feed was composed entirely of inorganic sulfate. During balance trials the N:S ratio in the feed varied from 6.1 to 9.5, and the sulfur content from 0.22 to 0.31 % of the dry matter. In every trial (seven with 0-feed and two with ULP-feed, of five or seven days duration, the cows were in high-positive sulfur balance. The 0-cows excreted a greater proportion of their total sulfur output via urine than the ULP-cows. The excretion of inorganic sulfate sulfur, as a proportion of the urinary and faecal sulfur, was greater for 0-cows than for ULP- or NorP-cows (cows on normal, protein-rich feed; the opposite was the case with regard to the excretion of ester sulfate sulfur and neutral sulfur. The sulfur contents of milk and blood showed only minor inter-feed differences. The sulfate content in the rumen fluid of the 0-cow rose rapidly after the commencement of feeding and then fell quite rapidly. We conclude tentatively that in the rumen of the 0-cow hydrogen sulfide is generated so quickly that the whole of it cannot be used for the synthesis of sulfur-containing compounds, a considerable proportion of it being lost in eructations or excreted as inorganic sulfates in the urine.

  1. Sulfur-Containing Agrochemicals.

    Science.gov (United States)

    Devendar, Ponnam; Yang, Guang-Fu

    2017-10-09

    Modern agricultural chemistry has to support farmers by providing innovative agrochemicals. In this context, the introduction of sulfur atoms into an active ingredient is still an important tool in modulating the properties of new crop-protection compounds. More than 30% of today's agrochemicals contain at least one sulfur atom, mainly in fungicides, herbicides and insecticides. A number of recently developed sulfur-containing agrochemical candidates represent a novel class of chemical compounds with new modes of action, so we intend to highlight the emerging interest in commercially active sulfur-containing compounds. This chapter gives a comprehensive overview of selected leading sulfur-containing pesticidal chemical families namely: sulfonylureas, sulfonamides, sulfur-containing heterocyclics, thioureas, sulfides, sulfones, sulfoxides and sulfoximines. Also, the most suitable large-scale synthetic methods of the recently launched or provisionally approved sulfur-containing agrochemicals from respective chemical families have been highlighted.

  2. A two-dimensional organic–inorganic hybrid compound, poly[(ethylenediaminetri-μ-oxido-oxidocopper(IImolybdenum(VI

    Directory of Open Access Journals (Sweden)

    Mehtap Emirdag-Eanes

    2008-10-01

    Full Text Available A new organic–inorganic two-dimensional hybrid compound, [CuMoO4(C2H8N2], has been hydrothermally synthesized at 443 K. The unit cell contains layers composed of CuN2O4 octahedra and MoO4 tetrahedra. Corner-sharing MoO4 and CuN2O4 polyhedra form CuMoO4 bimetallic sites that are joined together through O atoms, forming an edge-sharing Cu2Mo2O4 chain along the c axis. The one-dimensional chains are further linked through bridging O atoms that join the Cu and Mo atoms into respective chains along the b axis, thus establishing layers in the bc plane. The ethylenediamine ligand is coordinated to the Cu atom through its two N atoms and is oriented perpendicularly to the two-dimensional –Cu—O—Mo– layers. The average distance between adjacent layers, as calculated by consideration of the closest and furthest distances between two layers, is 8.7 Å. The oxidation states of the Mo and Cu atoms of VI and II, respectively, were confirmed by bond-valence sum calculations.

  3. Elaboration, structural, vibrational and optical investigation of a two-dimensional self-assembled organic–inorganic hybrid compound

    International Nuclear Information System (INIS)

    Dammak, T.; Boughzala, H.; Mlayah, A.; Abid, Y.

    2016-01-01

    Single crystals of a hybrid organic/inorganic material with the formula (C 4 N 3 H 16 )Cl[CuCl 4 ] were elaborated and studied by X-ray diffraction, and photoluminescence. The crystals consist of a self-assembled multilayer structure with a Pnam space group. The structure is built up from the staking of infinite two-dimensional layers of CuCl 6 corner-sharing octahedra, separated by organic (C 4 N 3 H 16 ) 3+ chains. Such a structure may be regarded as a multi quantum well system, in which CuCl 6 layers act as semiconductor wells and the organic molecules act as insulator barriers Furthermore, the room temperature IR and Raman spectra of the title compound were recorded and analyzed. For optical investigations, thin films have been prepared by spin-coating method from the ethanol solution of the material. Optical absorption spectra shows characteristic absorptions of CuCl-based layered perovskite centered at 300 and 380 nm, whereas the photoluminescence spectra shows a bleu intense emission around 420 nm, associated to radiative recombination of confined excitons in the CuCl 6 Quantum wells.

  4. Application of self-organising maps towards segmentation of soybean samples by determination of inorganic compounds content.

    Science.gov (United States)

    Cremasco, Hágata; Borsato, Dionísio; Angilelli, Karina Gomes; Galão, Olívio Fernandes; Bona, Evandro; Valle, Marcos Eduardo

    2016-01-15

    In this study, 20 samples of soybean, both transgenic and conventional cultivars, which were planted in two different regions, Londrina and Ponta Grossa, both located at Paraná, Brazil, were analysed. In order to verify whether the inorganic compound levels in soybeans varied with the region of planting, K, P, Ca, Mg, S, Zn, Mn, Fe, Cu and B contents were analysed by an artificial neural network self-organising map. It was observed that with a topology 10 × 10, 8000 epochs, initial learning rate of 0.1 and initial neighbourhood ratio of 4.5, the network was able to differentiate samples according to region of origin. Among all of the variables analysed by the artificial neural network, the elements Zn, Ca and Mn were those which most contributed to the classification of the samples. The results indicated that samples planted in these two regions differ in their mineral content; however, conventional and transgenic samples grown in the same region show no difference in mineral contents in the grain. © 2015 Society of Chemical Industry.

  5. Effects of oil drops containing Lactobacillus salivarius WB21 on periodontal health and oral microbiota producing volatile sulfur compounds.

    Science.gov (United States)

    Suzuki, Nao; Tanabe, Kazunari; Takeshita, Toru; Yoneda, Masahiro; Iwamoto, Tomoyuki; Oshiro, Sueko; Yamashita, Yoshihisa; Hirofuji, Takao

    2012-03-01

    The objective of this paper is to evaluate the effects of oil drops containing Lactobacillus salivarius WB21 on periodontal health and oral microbiota producing volatile sulfur compounds (VSCs). For this study, 42 subjects were randomly assigned to receive oil samples containing L. salivarius WB21 or a placebo for two weeks. Oral assessment and saliva collection were performed on days 1 and 15. Bacterial analysis was performed using the real-time polymerase chain reaction and terminal restriction fragment length polymorphism (T-RFLP). In both the experimental and placebo groups, the average probing depth, number of periodontal pockets, and the percentage of bleeding on probing (BOP) decreased while stimulated salivary flow increased on day 15. BOP was reduced in the experimental group compared with the placebo group (P = 0.010). In the experimental group, total bacterial numbers decreased, and the number of L. salivarius increased. The number of Prevotella intermedia, which is correlated with hydrogen sulfide concentration in mouth air, increased in the placebo group and did not change in the experimental group. T-RFLP analysis found that the peak area proportions representing Porphyromonas gingivalis, P. intermedia, Tannerella forsythensis, and Fusobacterium nucleatum decreased in the experimental group, although there was no significant change in the bacterial composition. Thus we observed oil drops containing L. salivarius WB21 improved BOP and inhibited the reproduction of total and VSC-producing periodontopathic bacteria compared with the placebo group, but also showed the limit of its efficacy in controlling VSCs producing and periodontal pathogens.

  6. A clinical and histopathological comparison of the effectiveness of salicylic acid to a compound of inorganic acids for the treatment of digital dermatitis in cattle

    DEFF Research Database (Denmark)

    Capion, N.; Larsson, E. K.; Nielsen, O. L.

    2018-01-01

    ; however, the demand for effective nonantibiotic alternatives is increasing. The objective was to evaluate the performance of 3 nonantibiotic topical treatments (salicylic acid and a compound of inorganic acids in a 20% solution and in a dry form) on DD in a commercial dairy herd. Within the 30-d test...... of spirochetes present in the epidermis), 2 (moderate number of spirochetes present and reaching an intermediary level in the epidermis), and 3 (large number of spirochetes present and reaching the deepest part of the epidermis or the superficial dermis). The improvement rate was 10/14 (71%) for salicylic acid......, 11/15 (73%) for the inorganic acid solution, and 8/13 (62%) for the inorganic acid powder. The analysis showed no difference among treatments. The association between clinical score and histopathological score was determined by an odds ratio. The odds ratio of a healed lesion having spirochetes...

  7. Water soluble inorganic trace gases and related aerosol compounds in the tropical boundary layer. An analysis based on real time measurements at a pasture site in the Amazon Basin

    NARCIS (Netherlands)

    Trebs, I.

    2005-01-01

    This dissertation investigates the behavior of water-soluble inorganic trace gases and related aerosol species in the tropical boundary layer. Mixing ratios of ammonia (NH3), nitric acid (HNO3), nitrous acid (HONO), hydrochloric acid (HCl), sulfur dioxide (SO;,) and the corresponding water-soluble

  8. Complete Oxidation of Propionate, Valerate, Succinate, and Other Organic Compounds by Newly Isolated Types of Marine, Anaerobic, Mesophilic, Gram-Negative, Sulfur-Reducing Eubacteria

    Science.gov (United States)

    Finster, Kai; Bak, Friedhelm

    1993-01-01

    Anaerobic enrichment cultures with either propionate, succinate, lactate, or valerate and elemental sulfur and inocula from shallow marine or deep-sea sediments were dominated by rod-shaped motile bacteria after three transfers. By application of deep-agar dilutions, five eubacterial strains were obtained in pure culture and designated Kyprop, Gyprop, Kysw2, Gylac, and Kyval. All strains were gram negative and grew by complete oxidation of the electron donors and concomitant stoichiometric reduction of elemental sulfur to hydrogen sulfide. The isolates used acetate, propionate, succinate, lactate, pyruvate, oxaloacetate, maleate, glutamate, alanine, aspartate, and yeast extract. All isolates, except strain Gylac, used citrate as an electron donor but valerate was oxidized only by strain Kyval. Fumarate and malate were degraded by all strains without an additional electron donor or acceptor. Kyprop, Gyprop, and Gylac utilized elemental sulfur as the sole inorganic electron acceptor, while Kysw2 and Kyval also utilized nitrate, dimethyl sulfoxide, or Fe(III)-citrate as an electron acceptor. Images PMID:16348934

  9. A SAW-Based Chemical Sensor for Detecting Sulfur-Containing Organophosphorus Compounds Using a Two-Step Self-Assembly and Molecular Imprinting Technology

    Directory of Open Access Journals (Sweden)

    Yong Pan

    2014-05-01

    Full Text Available This paper presents a new effective approach for the sensitive film deposition of surface acoustic wave (SAW chemical sensors for detecting organophosphorus compounds such as O-ethyl-S-2-diisopropylaminoethyl methylphosphonothiolate (VX containing sulfur at extremely low concentrations. To improve the adsorptive efficiency, a two-step technology is proposed for the sensitive film preparation on the SAW delay line utilizing gold electrodes. First, mono[6-deoxy-6-[(mercaptodecamethylenethio

  10. Analysis of organic sulfur compounds in atmospheric aerosols at the HKUST supersite in Hong Kong using HR-ToF-AMS.

    Science.gov (United States)

    Huang, Dan Dan; Li, Yong Jie; Lee, Berto P; Chan, Chak K

    2015-03-17

    Organic sulfur compounds have been identified in ambient secondary organic aerosols, but their contribution to organic mass is not well quantified. In this study, using a high-resolution time-of-flight aerosol mass spectrometer (AMS), concentrations of organic sulfur compounds were estimated based on the high-resolution fragmentation patterns of methanesulfonic acid (MSA), and organosulfates (OS), including alkyl, phenyl, and cycloalkyl sulfates, obtained in laboratory experiments. Mass concentrations of MSA and minimum mass concentrations of OS were determined in a field campaign conducted at a coastal site of Hong Kong in September 2011. MSA and OS together accounted for at least 5% of AMS detected organics. MSA is of marine origin with its formation dominated by local photochemical activities and enhanced by aqueous phase processing. OS concentrations are better correlated with particle liquid water content (LWC) than with particle acidity. High-molecular-weight OS were detected in the continental influenced period probably because they had grown into larger molecules during long-range transport or they were formed from large anthropogenic precursors. This study highlights the importance of both aqueous-phase processing and regional influence, i.e., different air mass origins, on organic sulfur compound formation in coastal cities like Hong Kong.

  11. Changes in salivary microbiota increase volatile sulfur compounds production in healthy male subjects with academic-related chronic stress.

    Directory of Open Access Journals (Sweden)

    Bruno Dias Nani

    Full Text Available To investigate the associations among salivary bacteria, oral emanations of volatile sulfur compounds, and academic-related chronic stress in healthy male subjects.Seventy-eight healthy male undergraduate dental students were classified as stressed or not by evaluation of burnout, a syndrome attributed to academic-related chronic stress. This evaluation was carried out using the Maslach Burnout Inventory-Student Survey questionnaire. Oral emanations of hydrogen sulfide, methyl mercaptan, and dimethyl sulfide were measured using an Oral Chroma™ portable gas chromatograph. The amounts in saliva of total bacteria and seven bacteria associated with halitosis were quantified by qPCR. The in vitro production of H2S by S. moorei and/or F. nucleatum was also measured with the Oral Chroma™ instrument.The stressed students group showed increased oral emanations of hydrogen sulfide and dimethyl sulfide, together with higher salivary Solobacterium moorei levels (p < 0.05, Mann Whitney test. There were moderate positive correlations between the following pairs of variables: Fusobacterium nucleatum and S. moorei; F. nucleatum and hydrogen sulfide; Tannerella forsythia and F. nucleatum; T. forsythia and S. moorei. These correlations only occurred for the stressed group (p < 0.05, Spearman correlation. The in vitro experiment demonstrated that S. moorei increased H2S production by F. nucleatum (p < 0.05, ANOVA and Tukey's test.The increased amount of S. moorei in saliva, and its coexistence with F. nucleatum and T. forsythia, seemed to be responsible for increased oral hydrogen sulfide in the healthy male stressed subjects.

  12. Metabolism of reduced methylated sulfur compounds in anaerobic sediments and by a pure culture of an estuarine methanogen

    International Nuclear Information System (INIS)

    Kiene, R.P.; Oremland, R.S.; Catena, A.; Miller, L.G.; Capone, A.G.

    1986-01-01

    Addition of dimethylsulfide (DMS), dimethyldisulfide (DMDS), or methane thiol (MSH) to a diversity of anoxic aquatic sediments (e.g., fresh water, estuarine, alkaline/hypersaline) stimulated methane production. The yield of methane recovered from DMS was often 52 to 63%, although high concentrations of DMS (as well as MSH and DMDS) inhibited methanogenesis in some types of sediments. Production of methane from these reduced methylated sulfur compounds was blocked by 2-bromoethanesulfonic acid. Sulfate did not influence the metabolism of millimolar levels of DMS, DMDs, or MSH added to sediments. However, when DMS was added at ∼2-3=M levels as [ 14 C]DMS, metabolism by sediments resulted in a 14 CH 4 / 14 CO 2 ratio of only 0.06. Addition of molybdate increased the ratio of 1.8, while 2-bromoethanesulfonic acid decreased it to 0, but did not block 14 CO 2 production. These results indicate the methanogens and sulfate reducers compete for DMS when it is present at low concentrations; however, at high concentrations, DMS is a noncompetitive substrate for methanogens. Metabolism of DMS by sediments resulted in the appearance of MSH as a transient intermediate. A pure culture of an obligately methylotrophic estuarine methanogen was isolated which was capable of growth on DMS. Metabolism of DMS by the culture also resulted in the transient appearance of MSH, but the organism could grow on neither MSH nor DMDS. The culture metabolized [ 14 C]-DMS to yield a 14 CH 4 / 14 CO 2 ratio of ∼ 2.8

  13. Prebiotic Synthesis of Methionine and Other Sulfur-Containing Organic Compounds on the Primitive Earth: A Contemporary Reassessment Based on an Unpublished 1958 Stanley Miller Experiment

    Science.gov (United States)

    Parker, Eric T.; Cleaves, H. James; Callahan, Michael P.; Dworkin, Jason P.; Glavin, Daniel P.; Lazcano, Antonio

    2010-01-01

    Original extracts from an unpublished 1958 experiment conducted by the late Stanley L. Miller were recently found and analyzed using modern state-of-the-art analytical methods. The extracts were produced by the action of an electric discharge on a mixture of methane (CH4), hydrogen sulfide (H2S), ammonia (NH3), and carbon dioxide (CO2). Racemic methionine was farmed in significant yields, together with other sulfur-bearing organic compounds. The formation of methionine and other compounds from a model prebiotic atmosphere that contained H2S suggests that this type of synthesis is robust under reducing conditions, which may have existed either in the global primitive atmosphere or in localized volcanic environments on the early Earth. The presence of a wide array of sulfur-containing organic compounds produced by the decomposition of methionine and cysteine indicates that in addition to abiotic synthetic processes, degradation of organic compounds on the primordial Earth could have been important in diversifying the inventory of molecules of biochemical significance not readily formed from other abiotic reactions, or derived from extraterrestrial delivery.

  14. Effects of rehydration nutrients on H2S metabolism and formation of volatile sulfur compounds by the wine yeast VL3.

    Science.gov (United States)

    Winter, Gal; Henschke, Paul A; Higgins, Vincent J; Ugliano, Maurizio; Curtin, Chris D

    2011-11-02

    In winemaking, nutrient supplementation is a common practice for optimising fermentation and producing quality wine. Nutritionally suboptimal grape juices are often enriched with nutrients in order to manipulate the production of yeast aroma compounds. Nutrients are also added to active dry yeast (ADY) rehydration media to enhance subsequent fermentation performance. In this study we demonstrate that nutrient supplementation at rehydration also has a significant effect on the formation of volatile sulfur compounds during wine fermentations. The concentration of the 'fruity' aroma compounds, the polyfunctional thiols 3-mercaptohexan-1-ol (3MH) and 3-mercaptohexyl acetate (3MHA), was increased while the concentration of the 'rotten egg' aroma compound, hydrogen sulfide (H2S), was decreased. Nutrient supplementation of the rehydration media also changed the kinetics of H2S production during fermentation by advancing onset of H2S production. Microarray analysis revealed that this was not due to expression changes within the sulfate assimilation pathway, which is known to be a major contributor to H2S production. To gain insight into possible mechanisms responsible for this effect, a component of the rehydration nutrient mix, the tri-peptide glutathione (GSH) was added at rehydration and studied for its subsequent effects on H2S formation. GSH was found to be taken up during rehydration and to act as a source for H2S during the following fermentation. These findings represent a potential approach for managing sulfur aroma production through the use of rehydration nutrients.

  15. Prediction of periodontopathic bacteria in dental plaque of periodontal healthy subjects by measurement of volatile sulfur compounds in mouth air.

    Science.gov (United States)

    Kishi, Mitsuo; Ohara-Nemoto, Yuko; Takahashi, Masahiro; Kishi, Kayo; Kimura, Shigenobu; Aizawa, Fumie; Yonemitsu, Masami

    2013-03-01

    The aim of this study was to determine whether measurements of volatile sulfur compounds (VSCs) are useful to predict colonization of periodontopathic bacteria. For this purpose, we assessed the relationships among distributions of 4 species of periodontopathic bacteria in tongue coating and dental plaque, oral conditions including VSC concentration in mouth air, and smoking habit of periodontal healthy young subjects. The subjects were 108 young adults (mean age, 23.5±2.56 years) without clinical periodontal pockets. Information regarding smoking habit was obtained by interview. After VSC concentration in mouth, air was measured with a portable sulfide monitor (Halimeter(®)), non-stimulated saliva flow and dental caries status were assessed, and tongue coating and dental plaque samples were collected from the subjects. The tongue coating samples were weighed to determine the amount. The colonization of Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, and Treponema denticola in both tongue coating and plaque samples was investigated using species-specific polymerase chain reaction assays. Significant relationships were observed between the colonization of periodontopathic bacteria in tongue coating and plaque samples, especially that of P. gingivalis. VSC concentration showed the most significant association with colonization of P. gingivalis in both tongue coating and dental plaque. Logistic regression analysis demonstrated that the adjusted partial correlation coefficient [Exp(B)] values for VSC concentration with the colonization of P. gingivalis, P. intermedia, and T. denticola in dental plaque were 135, 35.4 and 10.4, respectively. In addition, smoking habit was also shown to be a significant variable in regression models [Exp(B)=6.19, 8.92 and 2.53, respectively]. Therefore, receiver operating characteristic analysis was performed to predict the colonization of periodontal bacteria in dental plaque in the subjects divided by smoking

  16. Influence of inorganic compounds on the combustion of coal. III. The effect of water of constitution of added compounds, moisture, and mineral matter in coal

    Energy Technology Data Exchange (ETDEWEB)

    Newall, H F

    1939-01-01

    The effects on the combustion rate from excess moisture and the addition of selected inorganic substances to powdered coals were determined. The catalytic effect of 19 known inorganic ash constituents on combustion rates was also examined. Alumina and silica were found to inhibit combustion while ferric oxide accelerated it. Titanium, Ge, and B oxides, along with gypsum and calcium phosphate, decreased the rate of combusion, while Ca, Mg, Mn, and V oxides increased combustion rates. Although several of the ash constituents in coal directly affected combustion rates, the effect of adding them to the coal prior to combustion did not correlate with the effect of the mineral matter already in the coal.

  17. The Bi{sup 3+} 6s and 6p electron binding energies in relation to the chemical environment of inorganic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Awater, Roy H.P., E-mail: R.H.P.Awater@tudelft.nl; Dorenbos, Pieter

    2017-04-15

    This paper provides an overview and interpretation of the spectroscopic data of the Bi{sup 3+} activator ion in 117 different inorganic compounds. The energies of the metal-to-metal charge transfer and the interconfigurational transitions of Bi{sup 3+} were collected from the archival literature. Using these energies, in combination with the electron binding energies in the host conduction and valence band, the binding energies in the 6s ground state and 6p excited state were determined relative to the vacuum level. The locations of the Bi{sup 3+} energy levels within the forbidden gap of the host compound provides valuable insight in the physical properties of the Bi{sup 3+} activator ion in different compounds.

  18. Production of ultra-low-sulfur gasoline: an equilibrium and kinetic analysis on adsorption of sulfur compounds over Ni/MMS sorbents.

    Science.gov (United States)

    Subhan, Fazle; Liu, B S; Zhang, Q L; Wang, W S

    2012-11-15

    High performance nickel-based micro-mesoporous silica (Ni/MMS) sorbent was prepared by incipient wetness impregnation with ultrasonic aid (IWI-u) for adsorptive desulfurization (ADS) of commercial gasoline and simulated fuels. The sorbents were characterized with BET, XRD, TPR, SEM, HRTEM and TG/DTG. These results show that 20 wt%Ni/MMS (IWI-u) can still retain the framework of MMS and nickel particles were homogeneously distributed in the MMS channels without any aggregation, which improved significantly the ADS performance of the sorbents. The studies on the ADS kinetics indicate that the adsorption behavior of thiophene (T), benzothiophene (BT) and dibenzothiophene (DBT) over 20 wt%Ni/MMS (IWI-u) can be described appropriately by pseudo second-order kinetic model. The intraparticle diffusion model verified that the steric hindrance and intraparticle diffusion were the rate controlling step of the adsorption process of DBT molecules. Langmuir model can be used to describe the adsorption isotherms for T, BT and DBT due to low coverage. The regeneration sorbent maintains the sulfur removal efficiency of 85.9% for 6 cycles. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Activating Student to Learn Chemistry using Chemmy Card 6-1 Game as an Instructional Medium in IUPAC Nomenclature of Inorganic Compounds

    Science.gov (United States)

    Lutfi, A.; Hidayah, R.

    2018-01-01

    The aim of this study is to know the effect of Internet-assisted Chemmy Card 6-1 game as an instructional medium in IUPAC Nomenclature of Inorganic Compounds material for X grade of senior high school on students’ activity, learning motivation, and learning outcome. The study was conducted at SMA Negeri Sidoarjo, Indonesia, in two different classes. The instruction was done based on the lesson plan made. The observation on students’ activity was conducted during the instruction with the game while test and questionnaire were given after the instruction. The result showed positive activities, which students listened to the teacher’s explanation, actively delivered questions, and enabled to solve problems in naming compounds. It was also effective to avoid the drowsiness. The result of students’ motivation of X MIPA 6 was 74.78% (good) while X MIPA 7 was 83.80% (very good). The pretest results of two classes showed that no students mastered but 100% students mastered and the increase of N-gain scores in two classes was categorized as high, ≥0,7, after the instruction. The result of this study showed that the use of Internet-assisted Chemmy Card 6-1 game in IUPAC nomenclature of inorganic compounds for X grade of senior high school could be pleasant for students to learn and effective in achieving the learning objective.

  20. Use of some inorganic and organic compounds as decontaminants for cobalt-60 and caesium-134 by clover plant grown on Inshas sandy soil

    Energy Technology Data Exchange (ETDEWEB)

    Abdel Sabour, M.F.; El-Naggar, H.A.; Soliman, S.M. (Atomic Energy Establishment, Cairo (Egypt). Nuclear Chemistry Dept.)

    1991-01-01

    Outdoor lysimeter experiments were carried out to elucidate the effect of 4 inorganic and 3 organic salts on {sup 60}Co and {sup 134}Cs uptake and dry matter yield of three cuts of clover in the soils of Inshas. A new concept was proposed for assessing the difference in capacity of soil to supply radionuclides to plants as affected by applied inorganic or organic compounds. A relation of plant tissue radionuclide content with time can be expressed in an exponential equation with corresponding regression coefficients. When the same plant species is grown on the same soil differing only in the applied compounds (e.g. Fe-EDDHA, Fe-DTPA, Fe-OAC, Fe(COO){sub 2}, Al(OH){sub 3}, Ca(H{sub 2}PO{sub 4}){sub 2}, Fe{sub 2}O{sub 3}) the derived equation will change. Differences of either Co or Cs accumulation with time between control and any other treatment were evaluated. The data also show that Fe-DTPA is preferred for {sup 60}Co as enhancing compound for plant uptake (for decontamination use), compared with other applied salts, on the other hand, any tested salts did not significantly effect {sup 134}Cs taken by clover. It was also found that more than 70% of the total cobalt uptake was accumulated in the roots which indicate that Co is less mobile in plants than Cs. (orig.).

  1. Use of some inorganic and organic compounds as decontaminants for cobalt-60 and caesium-134 by clover plant grown on Inshas sandy soil

    International Nuclear Information System (INIS)

    Abdel Sabour, M.F.; El-Naggar, H.A.; Soliman, S.M.

    1991-01-01

    Outdoor lysimeter experiments were carried out to elucidate the effect of 4 inorganic and 3 organic salts on 60 Co and 134 Cs uptake and dry matter yield of three cuts of clover in the soils of Inshas. A new concept was proposed for assessing the difference in capacity of soil to supply radionuclides to plants as affected by applied inorganic or organic compounds. A relation of plant tissue radionuclide content with time can be expressed in an exponential equation with corresponding regression coefficients. When the same plant species is grown on the same soil differing only in the applied compounds (e.g. Fe-EDDHA, Fe-DTPA, Fe-OAC, Fe(COO) 2 , Al(OH) 3 , Ca(H 2 PO 4 ) 2 , Fe 2 O 3 ) the derived equation will change. Differences of either Co or Cs accumulation with time between control and any other treatment were evaluated. The data also show that Fe-DTPA is preferred for 60 Co as enhancing compound for plant uptake (for decontamination use), compared with other applied salts, on the other hand, any tested salts did not significantly effect 134 Cs taken by clover. It was also found that more than 70% of the total cobalt uptake was accumulated in the roots which indicate that Co is less mobile in plants than Cs. (orig.) [de

  2. Determination of oxygen in uranium compounds using sulfur monochloride; Dosage de l'oxygene dans les composes de l'uranium par la methode au monochlorure de soufre

    Energy Technology Data Exchange (ETDEWEB)

    Baudin, G; Besson, J; Blum, P L; Tran-Van, Danh [Commisariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1964-07-01

    The authors have described in an other paper (Anal. Chim. Acta, in press) a method for oxygen determination in uranium compounds, in which the sample is attacked by sulfur monochloride. The present paper is concerned with the experimental aspects of the method: apparatus procedure. (authors) [French] Les auteurs ont decrit dans une autre publication (Anal. Chim. Acta) a paraitre, une methode de dosage de l'oxygene dans les composes de l'uranium par attaque par le monochlorure de soufre, La presente note a pour but d'en preciser les techniques experimentale: appareillage, mode operatoire. (auteurs)

  3. The extraction of zirconium (IV) from sulfuric acid solutions with high-molecular weight quaternary ammonium compound

    International Nuclear Information System (INIS)

    Sato, Taichi; Watanabe, Hiroshi

    1982-01-01

    The extraction of zirconium sulfate in aqueous sulfuric acid solutions with trioctylmethylammonium chloride (Aliquat-336; R 3 R'NCl) in organic solvents has been investigated under different conditions. In addition, the organic phases extracted sulfuric acid and zirconium sulfate were examined by IR and NMR spectroscopies. It has been found that Aliquat-336 extracts zirconium (IV) from sulfuric acid solutions according to the following ion-exchange reactions. i) The extraction of sulfuric acid is at first carried out through the equilibria, SO 4 2 - (aq) + 2R 3 R'NCl(org) reversible (R 3 R'N) 2 SO 4 (org) + 2Cl - (aq), (R 3 R'N) 2 SO 4 (org) + H + (aq) + HSO 4- (aq) reversible 2R 3 R'NHSO 4 (org). ii) The extraction of zirconium is expressed as the equilibrium reaction, Zr(SO 4 ) 3 2 - (aq) + 2xR 3 R'NHSO 4 (org) + (1-x)(R 3 R'N) 2 SO 4 (org) reversible (R 3 R'N) 2 [Zr(SO 4 ) 3 ](org) + xH 2 SO 4 (aq) + SO 4 2 - (aq), x = [R 3 R'NHSO 4 ]/(2[(R 3 R'N) 2 SO 4 ] + [R 3 R'NHSO 4 ]). Moreover, the hydrolyzed species (R 3 R'N)[ZrO(OH)(SO 4 )] is formed when zirconium is further extracted in an organic phase. (author)

  4. Bioleaching of metals from soils or sediments using the microbial sulfur cycle

    NARCIS (Netherlands)

    Tichy, R.

    1998-01-01

    Reduced inorganic sulfur species like elemental sulfur or sulfide are sensitive to changes in oxidative environments. Generally, inorganic reduced sulfur exists in natural environments in a solid phase, whereas its oxidation leads to sulfur solubilization and a production of acidity. This

  5. Gaseous byproducts from high-temperature thermal conversion elemental analysis of nitrogen- and sulfur-bearing compounds with considerations for δ2H and δ18O analyses.

    Science.gov (United States)

    Hunsinger, Glendon B; Tipple, Christopher A; Stern, Libby A

    2013-07-30

    High-temperature, conversion-reduction (HTC) systems convert hydrogen and oxygen in materials into H2 and CO for δ(2)H and δ(18)O measurements by isotope ratio mass spectrometry. HTC of nitrogen- and sulfur-bearing materials produces unintended byproduct gases that could affect isotope analyses by: (1) allowing isotope exchange reactions downstream of the HTC reactor, (2) creating isobaric or co-elution interferences, and (3) causing deterioration of the chromatography. This study characterizes these HTC byproducts. A HTC system (ThermoFinnigan TC/EA) was directly connected to a gas chromatograph/quadrupole mass spectrometer in scan mode (m/z 8 to 88) to identify the volatile products generated by HTC at conversion temperatures of 1350 °C and 1450 °C for a range of nitrogen- and sulfur-bearing solids [keratin powder, horse hair, caffeine, ammonium nitrate, potassium nitrate, ammonium sulfate, urea, and three nitrated organic explosives (PETN, RDX, and TNT)]. The prominent HTC byproduct gases include carbon dioxide, hydrogen cyanide, methane, acetylene, and water for all nitrogen-bearing compounds, as well as carbon disulfide, carbonyl sulfide, and hydrogen sulfide for sulfur-bearing compounds. The 1450 °C reactor temperature reduced the abundance of most byproduct gases, but increased the significant byproduct, hydrogen cyanide. Inclusion of a post-reactor chemical trap containing Ascarite II and Sicapent, in series, eliminated the majority of byproducts. This study identified numerous gaseous HTC byproducts. The potential adverse effects of these gases on isotope ratio analyses are unknown but may be mitigated by higher HTC reactor temperatures and purifying the products with a purge-and-trap system or with chemical traps. Published in 2013. This article is a U.S. Government work and is in the public domain in the USA.

  6. Use of zeolites for the removal of volatile sulfur compounds from industrial waste gases and from natural gases

    Energy Technology Data Exchange (ETDEWEB)

    Dudzik,; Z,; Bilska, M

    1974-12-01

    The use of zeolites for the removal of sulfur dioxide from industrial waste gases and for the removal of hydrogen sulfide and volatile mercaptans from the natural gas or synthetic gas manufactured from coal is discussed. The effectiveness and cost of zeolite methods are superior to that of other methods. The best sorption properties with respect to sulfur dioxide are observed in faujasites and erionites. The molecular sieve 13X (a sodium form of low-silicon faujasite) is the most effective sorbent of hydrogen sulfide, produced commercially on a large scale. This zeolite is also a very effective catalyst for simultaneous oxygenation of hydrogen sulfide. The reaction with oxygen can begin at temperatures as low as -80/sup 0/C. The effectiveness of zeolite reactors is enhanced by the presence of oxygen in the gas being purified, and is hindered by the presence of water or water vapor. The extraordinary catalytic activity of sodium faujasites is due to free donors, and sulfur and oxygen ion donors at their surface. A zeolite reactor is also economical.

  7. New method for reduction of burning sulfur of coal

    International Nuclear Information System (INIS)

    Lyutskanov, L.; Dushanov, D.

    1998-01-01

    The coal pyrolysis is key phase in the the pyrolysis-combustion cycle as it provides char for combustor. The behaviour of sulfur compounds during coal pyrolysis depends on factors as rank of coal, quantity of sulfur and sulfur forms distribution in the coal, quantity and kind of mineral matter and the process conditions. The mineral content of coal may inhibit or catalyze the formation of volatile sulfur compounds. The pyrolysis itself is a mean of removing inorganic and organic sulfur but anyway a portion of it remains in the char while the other moves into the tar and gas. The aim of this study was to determine an optimal reduction of burning sulfur at the coal pyrolysis by varying parametric conditions. The pyrolysis of different kinds of coal has been studied. The samples with size particles o C at atmospheric pressure and with a heating rate of 6-50 o C min -1 . They were treated with exhaust gas and nitrogen at an addition of steam and air. The char obtained remains up to 10 min at the final temperature. The char samples cool without a contact with air. Two methods of desulfurization-pyrolysis were studied - using 9-vertical tubular reactor and 9-horizontal turning reactor. The results obtained show that at all samples there is a decrease of burning sulfur with maximal removal efficiency 83%. For example at a pyrolysis of Maritsa Iztok lignite coal the burning sulfur is only 16% in comparison with the control sample. The remained is 90% sulfate, 10% organic and pyrite traces when a mixture 'exhaust gas-water stream-air' was used. The method of desulfurization by pyrolysis could be applied at different kinds of coal and different conditions. Char obtained as a clean product can be used for generating electric power. This innovation is in a stage of patenting

  8. Identification of novel sulfur-containing steroids in sediments and petroleum: probable incorporation of sulfur into δ 5,7-sterols during early diagenesis

    Science.gov (United States)

    Sinninghe Damsté, Jaap S.; Schouten, Stefan; de Leeuw, Jan W.; van Duin, Adri C. T.; Geenevasen, Jan A. J.

    1999-01-01

    A novel sulfur-containing sterane, 4α,7α-epithio-5β-cholestane, has been identified in a sediment extract from the Miocene Northern Apennines marl (Italy) after its isolation by column chromatography and high pressure liquid chromatography. The compound has been characterised by GC-MS and mild Nickel boride desulfurisation and one and two-dimensional 1H NMR techniques. C 27-C 29 homologs have been detected in sediment extracts of three different formations and in one petroleum sample. These sulfur-containing steroids are probably formed by an intramolecular reaction of inorganic sulfides with early diagenetic products of Δ 5,7-sterols.

  9. Crystal structure, thermochromic and magnetic properties of organic-inorganic hybrid compound: (C7H7N2S)2CuCl4

    Science.gov (United States)

    Vishwakarma, Ashok K.; Kumari, Reema; Ghalsasi, Prasanna S.; Arulsamy, Navamoney

    2017-08-01

    The synthesis, thermal analysis, crystal structure and magnetic properties of (2-aminobenzothiazolium)2CuCl4, organic-inorganic hybrid compound, have been described. The compound crystallizes in the monoclinic space group P21/c with two formula units in a unit cell of dimensions a = 6.9522(4) Å, b = 9.6979(4) Å, c = 13.9633(6) Å, β = 97.849(3)° and volume 930.83(8) Å3 at 150(2) K. The structure consists of isolated nearly square planer [CuC14]2- units, with somewhat longer than normal Cusbnd Cl bond lengths [Cusbnd Cl (average) = 2.2711 Å]. The magnetic measurements of (2-aminobenzothiazolium)2CuCl4 using SQUID magnetometer show paramagnetic nature of the compound. Thermal measurements (TG-DTA and DSC) on this compound showed reversible phase transition at 83 °C. This transition is accompanied by the reversible change in colour of the prismatic crystal from green to dark brown, thermochromic behaviour. Temperature dependent EPR measurements on powdered sample ascertain change in coordination sphere around Cu(II) with shift in g|| = 2.150 and g⊥ = 2.071 at room temperature, typical of square planar, to g|| = 2.201 and g⊥ = 2.182 at 170 °C, typical of distorted tetrahedral geometry.

  10. Selective determination of semi-volatile thiophene compounds in water by molecularly imprinted polymer thin films with direct headspace gas chromatography sulfur chemiluminescence detection.

    Science.gov (United States)

    Hijazi, Hassan Y; Bottaro, Christina S

    2018-02-26

    Water-compatible molecularly imprinted polymer (MIP) thin films are coupled with headspace gas chromatography sulfur chemiluminescence detection (HS-GC-SCD) to create a new approach for the determination of trace concentrations of thiophene compounds in water samples. Thiophene compounds are persistent, typically petrogenic, organic pollutants of concern due to their potential for biomagnification and bioaccumulation, mutagenicity, and carcinogenicity in terrestrial and aquatic fauna. Identification and quantitation in water, particularly following oil spills, is a priority. Following adsorption of the thiophenes to the MIPs, the MIP-bound analytes are analyzed directly by HS-GC-SCD, with minimal sample manipulation and virtually no organic solvent. Calibration curves of spiked seawater were linear from 5 μg L -1 to 100 μg L -1 and limits of detection (LOD) were in the range of 0.24-0.82 μg L -1 . Low matrix effects were observed in the analysis of thiophene compounds in seawater making the method suitable for use in fresh and saline waters without modification. Acceptable reproducibility was obtained for analysis of thiophene compounds from spiked seawater samples at RSDs ≤7.0% (n = 3).

  11. Use of inorganic and organic compounds as decontaminates for cobalt T-60 and cesium-134 by clover plant grown on Inshas Sandy soil

    International Nuclear Information System (INIS)

    Abdel-Sabour, M.F.; El-naggr, H.A.; Soliman, S.M.

    1994-01-01

    Out door lysimeter experiment was carried out to elucidate the effect of four inorganic and three organic salts on 60 Co and 134 Cs uptake and dry matter yield of three cuts of clover in the soil Inshas A new concept was proposed for assessing the difference in capacity of soil to supply radionuclides (i.e. 60 Co and 134 Cs) to plants as affected by applied inorganic or organic compounds. The relation of plant tissues (P c ) Co/IR Cs content with increasing time can be expressed as log (Pc) = A + B log time (T), where A and B the regression. When the same plant species is grown on the same soil differ only in the applied compound (e.g. Fe-EDDHA, Fe-DTPA, Fe-O A C, Fe(Coo)z, A1(OH)3, Ca(H2 P O 4 )2 and Fe 2 O 3 ) the equation will change to, log (P'c) = A + B' log (T) (I). Based on both equations, the relationship between (Pc) becomes; log (P'c) = [(A'B')/(A B + A B ) [ +[1/A'B + A B ) [ log (Pc) (II). The intercept (C) and slope (S) in Eq. (II) were determined among 7 treatments (for either 60 Co or 134 Cs). Then the difference of either Co or Cs accumulation with time between control and any other treatment was evaluated according to (C) and (S) values. The data also that Fe-DTPA is preferred for 60 Co as enhancing compound for plant uptake (for decontamination use); compared with other applied salts; on the other hand, any tested salts did not significantly effect 134 Cs taken by clover. Also, it was found that more than 70% of total cobalt uptake was accumulated in the roots which indicate that Co is less mobile in plants than Cs. 3 figs., 4 tabs

  12. Organic and inorganic compounds in the water streams of the paper machine; Haitta-ainevirrat ja -tasot paperikoneella - PMST 01

    Energy Technology Data Exchange (ETDEWEB)

    Tervonen, P; Edelmann, K; Kaijaluoto, S [VTT Energy, Jyvaeskylae (Finland)

    1999-12-31

    The tightening standards for environmental protection set forth in legislation and the green consideration has reduced the environmental load of the paper and pulp industry significantly during recent years. Paper mills have decreased their water consumption by increasing internal circulation and by improving external effluent treatment. The consequence is that the concentrations of organic and inorganic dissolved and colloidal substances in the paper mill waters have risen. The fresh water consumption of paper machine can be decreased by cleaning the different water streams from the wire- and press-section and by lowering the amount of organic and inorganic materials led to paper machine water. In this case also water from mechanical pulping process and pulp itself should be cleaned. In this project the water use of modern paper machine and stream connections are studied. In addition flows, interactions and retention of dissolved and colloidal materials in the wet end of the paper machine are investigated. By utilizing this knowledge accurate simulation models of paper machine wet end can be created. With this model the various methods and technologies for controlling the harmful components in paper machine wet end are analyzed. (orig.)

  13. Organic and inorganic compounds in the water streams of the paper machine; Haitta-ainevirrat ja -tasot paperikoneella - PMST 01

    Energy Technology Data Exchange (ETDEWEB)

    Tervonen, P.; Edelmann, K.; Kaijaluoto, S. [VTT Energy, Jyvaeskylae (Finland)

    1998-12-31

    The tightening standards for environmental protection set forth in legislation and the green consideration has reduced the environmental load of the paper and pulp industry significantly during recent years. Paper mills have decreased their water consumption by increasing internal circulation and by improving external effluent treatment. The consequence is that the concentrations of organic and inorganic dissolved and colloidal substances in the paper mill waters have risen. The fresh water consumption of paper machine can be decreased by cleaning the different water streams from the wire- and press-section and by lowering the amount of organic and inorganic materials led to paper machine water. In this case also water from mechanical pulping process and pulp itself should be cleaned. In this project the water use of modern paper machine and stream connections are studied. In addition flows, interactions and retention of dissolved and colloidal materials in the wet end of the paper machine are investigated. By utilizing this knowledge accurate simulation models of paper machine wet end can be created. With this model the various methods and technologies for controlling the harmful components in paper machine wet end are analyzed. (orig.)

  14. Hydrogen bonded supra-molecular framework in inorganic-organic hybrid compounds: Syntheses, structures, and photoluminescent properties

    Science.gov (United States)

    Yan, Li; Liu, Wei; Li, Chuanbi; Wang, Yifei; Ma, Li; Dong, Qinqin

    2013-03-01

    Two novel compounds constructed from aromatic acid and N-Heterocyclic ligands have been synthesized by hydrothermal reaction: [Cd(mip)(1,8-NDC)(H2O)]2 (1) [mip = 2-(3-methoxyphenyl)-1H-imidazo[4,5-f][1,10]phenanthroline, 1,8-NDC = naphthalene-1,8-dicarboxylic acid] and Cd(mip)2(NTC)2 (2) [NTC = nicotinic acid]. Compounds 1 and 2 are characterized by elemental analysis, IR, single crystal X-ray diffraction and thermogravimetric analysis (TGA). Single-crystal X-ray investigation reveals that compounds 1-2 are 0 dimensional (0D) structures, and the existence of hydrogen bonds and π-π interactions lead the 0D to 2D novel framework. Hydrogen bonds and π-π interactions are powerful non-covalent intermolecular interactions for directing supra-molecular architectures. TG analysis shows clear courses of weight loss, which corresponds to the decomposition of different ligands. At room temperature, compound 1 exhibits emission at 449 nm upon excitation at 325 nm, and compound 2 shows a strong emission at 656 nm upon excitation at 350 nm. Fluorescent spectrum displays that compounds 1 and 2 are potential luminescent materials.

  15. Emissions monitoring in conveyed gas flow: (a) sulfur oxides and nitrogen oxides expressed respectively as SO{sub 2} and NO{sub 2}, (b) inorganic chlorine and fluorine compounds as gases and vapours expressed as HCl and HF; Rilevamento delle emissioni in flussi gassosi convogliati: (a) ossidid di zolfo e ossidi di azoto espressi rispettivamente come SO{sub 2} e NO{sub 2}, (b) composti inorganici del cloro e del fluoro sotto forma di gas e vapore espressi rispettivamente come HCl e HF

    Energy Technology Data Exchange (ETDEWEB)

    Ziemacki, G.; Viviano, G. [ed.] [Isituto Superiore di Sanita`, Rome (Italy). Gruppo di lavoro `Modifiche per il rilevamento delle emissioni in atmosfera da impianti industriali`

    1998-03-01

    The method (a) enables the determination of sulfur oxides (SO{sub 2}) and nitrogen oxides (NO{sub 2}) in conveyed atmospheric emissions. A stream of flue gas is a sampled by a heated with a filter housing and absorbed by an alkaline solution of potassium permanganate. The absorption solution is analyzed by ion-exchange chromatography for the determination of sulfate ion and nitrate ion as SO{sub 2} and NO{sub 2}. The method (b) enables the determination of hydrochloric acid (HCl) and hydrofluoric acid (HF) in conveyed atmospheric emissions. A stream of flue gas is sampled by a heated probe with a filter housing and absorbed by an alkaline solution (NaOH). The absorption solution is analyzed by ion-exchange chromatography for the determination of chloride ion and fluoride ion as HCl and HF. [Italiano] Il metodo a) consente la determinazione, in emissioni atmosferiche convogliate, degli ossidi di zolfo (SO{sub 2}) e degli ossidi di azoto (NO{sub 2}). Il campionamento viene effettuato mediante sonda riscaldata, munita di sistema filtrante, e sistema di assorbimento in soluzione alcalina di permanganato di potassio. La soluzione di assorbimento viene analizzata mediante cromatografia a scambio ionico, determinando le concentrazioni di ioni solfato e nitrato come SO{sub 2} ed NO{sub 2}. Il metodo b) consente la determinazione, in emissioni atmosferiche convogliate, dell`acido cloridrico (HCl) e dell`acido fluoridrico (HF). Il campionamento viene effettuato mediante sonda riscaldata, munita di sistema filtrante, e sistema di assorbimento in soluzione alcalina (NaOH). La soluzione alcalina viene quindi analizzata mediante cromatografia a scambio ionico, deter,mminando le concentrazioni di ioni cloro e fluoro come HCl e HF.

  16. Determination of organic compounds in medicinal plants, commercialized in capsulated forms and 'in natura' by wavelength dispersive X-ray fluorescence spectrometry (WDXRF). Determination of quantitative inorganic profiles

    International Nuclear Information System (INIS)

    Ferreira, Manuel Octavio M.; Sato, Ivone Mulako; Salvador, Vera Lucia R.

    2005-01-01

    X-ray fluorescence technique was used to determine major and trace elements for five Brazilian commercial medicinal plants. The bromobutane (Barbatimao), Ginkgo folium (Ginkgo biloba), Echinodorus macrophyllus (Chapeu de couro), Valeriana officinalis (Valeriana), Cordia salicifolia (Porangaba) samples were collected from three to six different commercial suppliers. The species were collected 'in natura' (leaves, flowers, barks and roots) and capsulated forms. The samples were grinded in liquid N 2 atmosphere and double layer pressed pellet were prepared. The elements Na, Mg, P, S, Cl, K, Ca, Mn, Fe, Ni, Cu, Zn, Rb e Sr concentrations were determined by individual calibration curves. The precision and accuracy of method were evaluated by certified reference material, NIST 1547 - Peach Leaves and the Chauvenet, Cochrane, ANOVA and Z-score statistical tests were applied. Each specimen presented a distinct inorganic profile and a great variation in its composition was observed. The inorganic profile will contribute for the elaboration of a quality and security guide to assure the phytotherapics commercialization. Moreover, these profiles could be used as complementary data to active farmaco compounds profiles for specimen's ratification. (author)

  17. Study on ionizing radiation effects in diesel and crude oil: organic compounds, hydrocarbon, sulfur and nitrogen; Estudo do efeito da radiacao ionizante em compostos organicos do diesel e do petroleo: hidrocarbonetos, sulfurados e nitrogenados

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, Luana dos Santos

    2014-07-01

    Petroleum is the most important energy and pollution source in the world, nowadays. New technologies in petrochemical industry aim to minimize energy spending at the process and to reduce pollution products. Sulfur and nitrogen compounds generate environmental problems; the most relevant is air pollution that affects the population health directly. The nuclear technology has been used in environmental protection through pollutants removal by free radicals produced at action of the radiation in water molecule. The objective of this study is to evaluate the radiation effects on oil and diesel, mainly in the hydrocarbons, organic sulfur, and nitrogen compounds. It was studied a molecule model of sulfur, named benzothiophene, diesel and crude oil samples. The samples were irradiated using a Co-60 source, Gammacell type. The total sulfur concentration in the samples was determined by X-ray fluorescence spectrometry, and organic compounds were analyzed by gas chromatography coupled to mass spectrometry (GC-MS). The study of molecular model showed that 95% was degraded at 20 kGy dose rate. Irradiation at 15 kGy of absorbed dose showed some cracking in petrol hydrocarbons, however with higher doses it was observed polymerization and low efficiency of cracking. It was observed that the sulfur compounds from diesel and petroleum was efficiently reduced. The applied doses of 15 kGy and 30 kGy were the most efficient on desulfurization of petroleum, and for diesel the highest variation was observed with 30 kGy and 50 kGy of absorbed dose. The distillation and chromatographic separation using an open column with palladium chloride as stationary phase showed a preferential separation of organic sulfur compounds in petroleum. (author)

  18. Effective atomic number and effective electron densities of some inorganic compounds for Compton effect in the gamma energy range 280 keV to 1115 keV

    International Nuclear Information System (INIS)

    Prasannakumar, S.; Umesh, T.K.

    2014-01-01

    The effective atomic number and effective electron densities of some inorganic compounds for Compton effect in the gamma energy range 280 keV to 1115 keV by using Compton scattering cross sections which are determined on a goniometer assembly. An ORTEC model 23210 gamma-x high purity germanium detector (HpGe) has been used to record the data along with a personal computer based MCA in the angular region 50°-110°. The effective atomic numbers so obtained were found to be equal to the total number of electrons present in the sample in accordance with the chemical formula. The results so obtained are of first of their kind at these energies and are expected to be important in a variety of applications of radiation physics and chemistry. (author)

  19. Methods for estimating the enthalpy of formation of inorganic compounds; thermochemical and crystallographic investigations of uranyl salts of group VI elements

    International Nuclear Information System (INIS)

    Brandenburg, N.P.

    1978-01-01

    The first part of this thesis is concerned with parameter methods for estimating the standard enthalpy of formation, ΔH 0 sub(f), of inorganic compounds. In this type of method the estimate is a function of parameters, assigned to cation and anion, respectively. The usefulness of a new estimation method is illustrated in the case of uranyl sulphide. In the second part of this thesis crystallographic and thermochemical properties of uranyl salts of group VI elements are described. Crystal structures are given for β-UO 2 SO 4 , UO 2 SeO 3 , and α-UO 2 SeO 4 . Thermochemical measurements have been restricted to the determination of ΔH 0 sub(f)(UO 2 SO 3 ) and ΔH 0 sub(f)(UO 2 TeO 3 ) by means of isoperibol solution calorimetry. (Auth.)

  20. Large fractions of CO2-fixing microorganisms in pristine limestone aquifers appear to be involved in the oxidation of reduced sulfur and nitrogen compounds

    Science.gov (United States)

    Herrmann, Martina; Rusznyák, Anna; Akob, Denise M.; Schulze, Isabel; Opitz, Sebastian; Totsche, Kai Uwe; Küsel, Kirsten

    2015-01-01

    The traditional view of the dependency of subsurface environments on surface-derived allochthonous carbon inputs is challenged by increasing evidence for the role of lithoautotrophy in aquifer carbon flow. We linked information on autotrophy (Calvin-Benson-Bassham cycle) with that from total microbial community analysis in groundwater at two superimposed—upper and lower—limestone groundwater reservoirs (aquifers). Quantitative PCR revealed that up to 17% of the microbial population had the genetic potential to fix CO2 via the Calvin cycle, with abundances of cbbM and cbbL genes, encoding RubisCO (ribulose-1,5-bisphosphate carboxylase/oxygenase) forms I and II, ranging from 1.14 × 103 to 6 × 106 genes liter−1 over a 2-year period. The structure of the active microbial communities based on 16S rRNA transcripts differed between the two aquifers, with a larger fraction of heterotrophic, facultative anaerobic, soil-related groups in the oxygen-deficient upper aquifer. Most identified CO2-assimilating phylogenetic groups appeared to be involved in the oxidation of sulfur or nitrogen compounds and harbored both RubisCO forms I and II, allowing efficient CO2 fixation in environments with strong oxygen and CO2 fluctuations. The genera Sulfuricellaand Nitrosomonas were represented by read fractions of up to 78 and 33%, respectively, within the cbbM and cbbL transcript pool and accounted for 5.6 and 3.8% of 16S rRNA sequence reads, respectively, in the lower aquifer. Our results indicate that a large fraction of bacteria in pristine limestone aquifers has the genetic potential for autotrophic CO2 fixation, with energy most likely provided by the oxidation of reduced sulfur and nitrogen compounds.

  1. Bipolar Mass Spectrometry of Labile Coordination Complexes, Redox Active Inorganic Compounds, and Proteins Using a Glass Nebulizer for Sonic-Spray Ionization

    Science.gov (United States)

    Antonakis, Manolis M.; Tsirigotaki, Alexandra; Kanaki, Katerina; Milios, Constantinos J.; Pergantis, Spiros A.

    2013-08-01

    In this study, we report on the development of a novel nebulizer configuration for sonic-spray ionization (SSI) mass spectrometry (MS), more specifically for a version of SSI that is referred to as Venturi easy ambient sonic-spray ionization (V-EASI) MS. The developed nebulizer configuration is based on a commercially available pneumatic glass nebulizer that has been used extensively for aerosol formation in atomic spectrometry. In the present study, the nebulizer was modified in order to achieve efficient V-EASI-MS operation. Upon evaluating this system, it has been demonstrated that V-EASI-MS offers some distinct advantages for the analysis of coordination compounds and redox active inorganic compounds over the predominantly used electrospray ionization (ESI) technique. Such advantages, for this type of compounds, are demonstrated here for the first time. More specifically, a series of labile heptanuclear heterometallic [CuII 6LnIII] clusters held together with artificial amino acid ligands, in addition to easily oxidized inorganic oxyanions of selenium and arsenic, were analyzed. The observed advantages pertain to V-EASI appearing to be a "milder" ionization source than ESI, not requiring electrical potentials for gas phase ion formation, thus eliminating the possibility of unwanted redox transformations, allowing for the "simultaneous" detection of negative and positive ions (bipolar analysis) without the need to change source ionization conditions, and also not requiring the use of syringes and delivery pumps. Because of such features, especially because of the absence of ionization potentials, EASI can be operated with minimal requirements for source parameter optimization. We observed that source temperature and accelerating voltage do not seem to affect labile compounds to the extent they do in ESI-MS. In addition, bipolar analysis of proteins was demonstrated here by acquiring both positive and negative ion mass spectra from the same protein solutions

  2. Studying sulfur functional groups in Norway spruce year rings using S L-edge total electron yield spectroscopy

    International Nuclear Information System (INIS)

    Struis, Rudolf P.W.J.; Ludwig, Christian; Barrelet, Timothee; Kraehenbuehl, Urs; Rennenberg, Heinz

    2008-01-01

    Profiles of the major sulfur functional groups in mature Norway spruce wood tissue have been established for the first time. The big challenge was the development of a method suitable for sulfur speciation in samples with very low sulfur content (< 100 ppm). This became possible by synchrotron X-ray absorption spectroscopy at the sulfur L-edge in total electron yield (TEY) detection mode with thin gold-coated wood slices. Functional groups were identified using sulfur compound spectra as fingerprints. Latewood of single year rings revealed metabolic plausible sulfur forms, particularly inorganic sulfide, organic disulfide, methylthiol, and highly oxidized sulfur. Form-specific profiles with Norway spruces from three different Swiss forest sites revealed high, but hitherto little-noticed, sulfur intensities attributable to natural heartwood formation and a common, but physiologically unexpected maximum around year ring 1986 with trees from the industrialized Swiss Plateau. It is hypothesized whether it may have resulted from the huge reduction in sulfur emissions after 1980 due to Swiss policy. Comparison with total S content profiles from optical emission spectroscopy underlined the more accurate and temporally better resolved TEY data with single wood year rings and it opened novel insights into the wood cell chemistry

  3. Study by mass spectrometry of the formation of cluster ions generated by laser ablation/ionization of inorganic compounds: application to the differentiation of trivalent and hexavalent chromium compounds

    International Nuclear Information System (INIS)

    Aubriet, Frederic

    1999-01-01

    The introduction of new ionization techniques allows a fast growth of mass spectrometry applications in an increasing number of fields. More particularly, the introduction of laser ablation/ionization process and the design of new instruments (laser microprobes), has been very important for a better knowledge of inorganic compound mass spectrometry. The purposes of this work were mainly focussed firstly in the understanding of cluster ions formation process by laser ablation/ionization and secondly in the development of a new mass spectrometry technique for the speciation between trivalent and hexavalent chromium compounds. We show that cluster ion formation are multiple. The difficulty to identify clearly the processes involved is due to the superposition of many mechanisms. Mostly, these processes are representative of the complexity of the gas-phase chemistry between the various species generated by laser ablation/ionization. Thus, four mechanisms for the cluster ion formation have been highlighted. The most frequently met correspond to aggregative processes of neutral molecules on precursor ions. The knowledge of the processes of cluster ion formation allows us to explain why it is possible to distinguish the oxidation number of chromium. The organigram of chromium valence speciation proposed is based on the calculation of the ratio of negative cluster ion intensities after systematic analysis of nearly twenty chromium reference compounds using the same instrumental conditions. The examination of mixtures between 1) calcium. silicon, trivalent iron or zinc oxides and 2) the standard chromium compound allows us to observe the influence of these oxides on the fingerprints of the pure chromium compounds and to determine up to which point and with which limitations, the methodology suggested, could be applied to the analysis of trivalent and hexavalent chromium compounds in complex and polyphasic matrices

  4. Vacuum energy referred Ti3+/4+ donor/acceptor states in insulating and semiconducting inorganic compounds

    International Nuclear Information System (INIS)

    Rogers, E.G.; Dorenbos, P.

    2014-01-01

    Optical spectroscopy data has been collected on the energy needed for electron transfer from the valence band to Ti 4+ in about 40 different insulating and II–VI and III–V semiconducting compounds. It provides a measure for the location of the Ti 3+ 3d 1 ground state level above the valence band. This is combined with the vacuum referred binding energy (VRBE) of valence band electrons as obtained with the chemical shift model based on lanthanide impurity spectroscopy. It provides the VRBE of an electron in the Ti 3+ ground state level. This work will first show that the energy of electron transfer to Ti 4+ is about the same as that to Eu 3+ irrespective of the type of compound. Next it will be shown that the VRBE of the Ti 3+ 3d 1 ground state is always near −4 eV. An approximately ±1 eV spread around that value is attributed to the crystal field splitting of the Ti 3+ 3d-levels. - Highlights: • Data on the energy of charge transfer (CT) to Ti 4+ in 38 compounds was collected. • A correlation between the Ti 4+ and Eu 3+ CT energies has been established. • The chemical shift model has been applied to Ti impurity states. • The Ti 3+ ground state binding energy is always around −4±1 eV

  5. Radionuclides, stable isotopes, inorganic constituents, and organic compounds in water from selected wells and springs from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman Area, Idaho, 1995

    International Nuclear Information System (INIS)

    Bartholomay, R.C.; Williams, L.M.; Campbell, L.J.

    1996-09-01

    The US Geological Survey and the Idaho Department of Water Resources, in cooperation with the US Department of Energy, sampled 17 sites as part of a long-term project to monitor water quality of the Snake River Plain aquifer from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman area. Water samples were collected and analyzed for selected radionuclides, stable isotopes, inorganic constituents, and organic compounds. The samples were collected from 11 irrigation wells, 2 domestic wells, 2 stock wells, 1 spring, and 1 public-supply well. Two quality assurance samples also were collected and analyzed. None of the radionuclide, inorganic constituents, or organic compound concentrations exceeded the established maximum contaminant levels for drinking water. Many of the radionuclide and inorganic constituent concentrations were greater than their respective reporting levels. All samples analyzed for dissolved organic carbon had concentrations that were greater than the minimum reporting level

  6. Synthesis of boronate-functionalized organic-inorganic hybrid monolithic column for the separation of cis-diol containing compounds at low pH.

    Science.gov (United States)

    Zhao, Heqing; Lyu, Haixia; Qin, Wenfei; Xie, Zenghong

    2018-04-01

    In this work, an organic-inorganic hybrid boronate affinity monolithic column was prepared via "one-pot" process using 4-vinylphenylboronic acid as organic monomer and divinylbenzene as cross-linker. The effects of reaction temperature, solvents and composition of organic monomers on the column properties (e.g. morphology, permeability, and mechanical stability) were investigated. A series of test compounds including small neutral molecules, aromatic amines, and cis-diol compounds were used to evaluate the retention behaviors of the prepared hybrid monolithic column. The results demonstrated that the prepared hybrid monolith exhibited mixed-interactions including hydrophilicity, cation exchange, and boronate affinity interaction. The run-to-run, day-to-day and batch-to-batch reproducibilities of the prepared hybrid monolith for thiourea's retention time were satisfactory with the relative standard deviations (RSDs) less than 0.09, 1.45 and 4.05% (n = 3), respectively, indicating the effectiveness and practicability of the proposed method. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Crystal structure and electrical conduction of the new organic-inorganic compound (CH2)2(NH3)2CdI4

    Science.gov (United States)

    Zhang, Liuqi; Wang, Jilin; Han, Feifei; Mo, Shuyi; Long, Fei; Gao, Yihua

    2018-03-01

    The new organic-inorganic compound (CH2)2(NH3)2CdI4 was prepared by slow evaporation method using a mixture solution of CdI2 and ethylenediamine iodide (EDAI) in the γ-butyrolactone (GBL). The synthesized compound was further characterized by single crystal diffraction, Infrared (IR) and Raman spectroscopy, energy dispersive spectrometer (EDS), X-Ray photoelectron spectroscopy (XPS) and thermogravimetric analysis. The relaxation behavior and conductivity mechanism of (CH2)2(NH3)2CdI4 was studied by the electrical impedance spectroscopy. The results indicated that (CH2)2(NH3)2CdI4 had a monoclinic structure with space group P21/c at room temperature. The complex impedance plotted as semicircle arcs and the proposed electrical equivalent circuit was to interpret the impedance behavior at different temperatures. The electrical equivalent circuit was made of a parallel combination of resistance (R) and fractal capacitance (CPE). Furthermore, the alternating current conductivity of the sample obeyed the Jonscher's law: σf =σdc + Afs and the conduction could be attributed to the correlated barrier hopping (CBH) model.

  8. Oxidative treatment of bromide-containing waters: formation of bromine and its reactions with inorganic and organic compounds--a critical review.

    Science.gov (United States)

    Heeb, Michèle B; Criquet, Justine; Zimmermann-Steffens, Saskia G; von Gunten, Urs

    2014-01-01

    Bromide (Br(-)) is present in all water sources at concentrations ranging from ≈ 10 to >1000 μg L(-1) in fresh waters and about 67 mg L(-1) in seawater. During oxidative water treatment bromide is oxidized to hypobromous acid/hypobromite (HOBr/OBr(-)) and other bromine species. A systematic and critical literature review has been conducted on the reactivity of HOBr/OBr(-) and other bromine species with inorganic and organic compounds, including micropollutants. The speciation of bromine in the absence and presence of chloride and chlorine has been calculated and it could be shown that HOBr/OBr(-) are the dominant species in fresh waters. In ocean waters, other bromine species such as Br2, BrCl, and Br2O gain importance and may have to be considered under certain conditions. HOBr reacts fast with many inorganic compounds such as ammonia, iodide, sulfite, nitrite, cyanide and thiocyanide with apparent second-order rate constants in the order of 10(4)-10(9)M(-1)s(-1) at pH 7. No rate constants for the reactions with Fe(II) and As(III) are available. Mn(II) oxidation by bromine is controlled by a Mn(III,IV) oxide-catalyzed process involving Br2O and BrCl. Bromine shows a very high reactivity toward phenolic groups (apparent second-order rate constants kapp ≈ 10(3)-10(5)M(-1)s(-1) at pH 7), amines and sulfamides (kapp ≈ 10(5)-10(6)M(-1)s(-1) at pH 7) and S-containing compounds (kapp ≈ 10(5)-10(7)M(-1)s(-1) at pH 7). For phenolic moieties, it is possible to derive second-order rate constants with a Hammett-σ-based QSAR approach with [Formula in text]. A negative slope is typical for electrophilic substitution reactions. In general, kapp of bromine reactions at pH 7 are up to three orders of magnitude greater than for chlorine. In the case of amines, these rate constants are even higher than for ozone. Model calculations show that depending on the bromide concentration and the pH, the high reactivity of bromine may outweigh the reactions of chlorine during

  9. Estimation of transport parameters of phenolic compounds and inorganic contaminants through composite landfill liners using one-dimensional mass transport model

    International Nuclear Information System (INIS)

    Varank, Gamze; Demir, Ahmet; Yetilmezsoy, Kaan; Bilgili, M. Sinan; Top, Selin; Sekman, Elif

    2011-01-01

    Highlights: → We conduct 1D advection-dispersion modeling to estimate transport parameters. → We examine fourteen phenolic compounds and three inorganic contaminants. → 2-MP, 2,4-DCP, 2,6-DCP, 2,4,5-TCP, 2,3,4,6-TeCP have the highest coefficients. → Dispersion coefficients of Cu are determined to be higher than Zn and Fe. → Transport of phenolics can be prevented by zeolite and bentonite in landfill liners. - Abstract: One-dimensional (1D) advection-dispersion transport modeling was conducted as a conceptual approach for the estimation of the transport parameters of fourteen different phenolic compounds (phenol, 2-CP, 2-MP, 3-MP, 4-MP, 2-NP, 4-NP, 2,4-DNP, 2,4-DCP, 2,6-DCP, 2,4,5-TCP, 2,4,6-TCP, 2,3,4,6-TeCP, PCP) and three different inorganic contaminants (Cu, Zn, Fe) migrating downward through the several liner systems. Four identical pilot-scale landfill reactors (0.25 m 3 ) with different composite liners (R1: 0.10 + 0.10 m of compacted clay liner (CCL), L e = 0.20 m, k e = 1 x 10 -8 m/s, R2: 0.002-m-thick damaged high-density polyethylene (HDPE) geomembrane overlying 0.10 + 0.10 m of CCL, L e = 0.20 m, k e = 1 x 10 -8 m/s, R3: 0.002-m-thick damaged HDPE geomembrane overlying a 0.02-m-thick bentonite layer encapsulated between 0.10 + 0.10 m CCL, L e = 0.22 m, k e = 1 x 10 -8 m/s, R4: 0.002-m-thick damaged HDPE geomembrane overlying a 0.02-m-thick zeolite layer encapsulated between 0.10 + 0.10 m CCL, L e = 0.22 m, k e = 4.24 x 10 -7 m/s) were simultaneously run for a period of about 540 days to investigate the nature of diffusive and advective transport of the selected organic and inorganic contaminants. The results of 1D transport model showed that the highest molecular diffusion coefficients, ranging from 4.77 x 10 -10 to 10.67 x 10 -10 m 2 /s, were estimated for phenol (R4), 2-MP (R1), 2,4-DNP (R2), 2,4-DCP (R1), 2,6-DCP (R2), 2,4,5-TCP (R2) and 2,3,4,6-TeCP (R1). For all reactors, dispersion coefficients of Cu, ranging from 3.47 x 10 -6 m 2 /s to 5

  10. Means of absorption for dry removal of sulfur dioxide from slack gases. Absorptionsmittel fuer die trockene Entfernung von Schwefedioxid aus Rauchgasen

    Energy Technology Data Exchange (ETDEWEB)

    Gebhard, G; Glaser, W; Hein, K

    1984-03-01

    This is a means of absorption for the dry removal of sulfur dioxide and other harmful substances from the stack gases from boilers. The means of absorption consists mainly of a fine-grained inorganic alkaline earth compound, particularly a calcium and/or a magnesium compound and an additive in the form of one or more carbonic acids and/or of their alkali salts, ammonium salts or alkaline earth salts.

  11. Formation of inorganic nanofibers by heat-treatment of poly(vinyl alcohol-zirconium compound hybrid nanofibers

    Directory of Open Access Journals (Sweden)

    Nakane K.

    2013-01-01

    Full Text Available Poly(vinyl alcohol-zirconium compound hybrid nanofibers (precursors were formed by electrospinning employing water as a solvent for the spinning solution. The precursors were converted into oxide (ZrO2, carbide (ZrC or nitride (ZrN nanofibers by heating them in air, Ar or N2 atmospheres. Monoclinic ZrO2 nanofibers with high-specific surface area were obtained by heat-treatment of the precursors in air. ZrC and ZrN nanofibers could be obtained below theoretical temperatures calculated from thermodynamics data.

  12. Gas-phase fragmentation of coordination compounds: loss of CO(2) from inorganic carbonato complexes to give metal oxide ions

    Science.gov (United States)

    Dalgaard; McKenzie

    1999-10-01

    Using electrospray ionization mass spectrometry, novel transition metal oxide coordination complex ions are proposed as the products of the collision-induced dissociation (CID) of some carbonato complex ions through the loss of a mass equivalent to CO(2). CID spectra of [(tpa)CoCO(3)](+) (tpa = tris(2-pyridylmethyl)methylamine), [(bispicMe(2)en)Fe(&mgr;-O)(&mgr;-CO(3))Fe(bispicMe(2)en)]2+ (bispicMe(2)en = N,N'-dimethyl-N,N'-bis(2-pyridylmethy)eth- ane-1, 2-diamine) and [(bpbp)Cu(2)CO(3)](+) (bpbp(-) = bis[(bis-(2-pyridylmethyl)amino)methyl]-4-tertbutylpheno-lato(1-)), show peaks assigned to the mono- and dinuclear oxide cations, [(tpa)CoO](+), [(bispicMe(2)en)(2)Fe(2)(O)(2)]2+ and [(bpbp)Cu(2)O](+), as the dominant species. These results can be likened to the reverse of typical synthetic reactions in which metal hydroxide compounds react with CO(2) to give metal carbonato compounds. Because of the lack of available protons in the gas phase, novel oxide species rather than the more common hydroxide ions are generated. These oxide ions are relevant to the highly oxidizing species proposed in oxygenation reactions catalysed by metal oxides and metalloenzymes. Copyright 1999 John Wiley & Sons, Ltd.

  13. Pressure effects on the magnetic behaviour of copper (II) compounds: magnetic ordering of layered organic/inorganic magnets

    International Nuclear Information System (INIS)

    Levchenko, G; Varyukhin, V N; Berezhnaya, L V; Rusakov, V F

    2012-01-01

    The high hydrostatic pressure effect on the magnetic properties of the layered hybrid compounds Cu 2 (OH) 3 (C n H 2n+1 CO 2 )⋅mH 2 O with distance between magnetic layers of up to 40 Å is studied. It is shown that the temperature of the ferromagnetic ordering decreases linearly with pressure increase. From measurements of susceptibility in the paramagnetic region, using both quantum Heisenberg and Ising exchange coupling models in layers and dipole interaction between layers, the in- and interlayer interactions are deduced. The dipole interactions are calculated and are shown to coincide with the model of Ising interactions in the layers. The value and decrease of T c under pressure are mainly driven by the value and decrease of the in-plane interactions. The formation of the long range ordering in the layered sample with dipolar interaction between layers is analysed. As a conclusion it is suggested that for designing high temperature ferromagnetism in layer compounds it is enough to have large in-plane interactions of ions with specific symmetry in layers and weak dipole interactions between layers. (paper)

  14. Linde Rectiscol{reg_sign} process. The most economic and experienced wash process for removal of sulfur compounds and CO{sub 2} from gasification gases

    Energy Technology Data Exchange (ETDEWEB)

    Kaballo, H.-P.; Kerestceciogly, U. [Linde AG, Hoellriegelskreuth (Germany). Linde Engineering Division

    2006-07-01

    The Recitsol{reg_sign} wash process is a well-proven process for the removal of H{sub 2}S/COS and CO{sub 2} from coal, asphalt, pitch or oil derived synthesis gas. It is a physical gas wash system using methanol as solvent at operating temperatures below water freezing point, to produce a synthesis gas with less than 0.1 vppm of total sulfur. The CO{sub 2} content can be adjusted in a range from several mol-percent down to a few ppm, as is required by the specified application. Its main advantages are the use of cheap and readily available methanol as solvent, the very flexible process configuration, and rather low utility consumption figures compared with other wash processes, like PEGE based process or chemical washes. A modern concept of a Rectisol{reg_sign} unit is described, to treat shifted and un-shifted gases in just one plant: shifted gas was used for hydrotreating in a refinery. Unshifted gas was used as fuel gas for power generation in an IGCC. CO{sub 2} of the unshifted feed gas was removed only partly, because the remaining CO{sub 2} was fed as inert gas together with the fuel gas to an IGCC. All sulfur compounds of both feed gases were concentrated in one single stream with a high H{sub 2}S concentration. Impurities like NH{sub 3}, HCN or metal carbonyls were eliminated nearly quantitatively. 4 refs., 4 figs., 3 tabs.

  15. Nitrogen, oxygen or sulfur containing heterocyclic compounds as analgesic drugs used as modulators of the nitroxidative stress.

    Science.gov (United States)

    Salat, Kinga; Moniczewski, Andrzej; Librowski, Tadeusz

    2013-03-01

    Numerous lines of evidence suggest that heterocyclic compounds used as analgesic, anti-inflammatory and anti-migraine agents can be potent regulators of the nitroxidative stress and targeting free nitrogen and oxygen radicals is a very promising strategy for future pain management. Both classical analgesics (nonsteroidal anti-inflammatory drugs, opioid drugs) and many analgesic adjuvants, including desipramine, duloxetine, fluoxetine, paroxetine, escitalopram, phenytoin or carbamazepine and α-lipoic acid can modulate the balance between pro-oxidant and antioxidant processes in the mammalian tissues and these properties of drugs such as indomethacin, meloxicam, tenoxicam, valdecoxib or some metabolites of analgesic drugs formed by the activity of tissue peroxidases may contribute to their clinical efficacy and drug-related toxic effects, including gastrointestinal ulcers, hepatic failure, agranulocytosis, aplastic anemia, neutropenia, opiate-induced hyperalgesia and tolerance. The antioxidant capacities of novel heterocyclic compounds, including the compounds acting either by prevention of formation or catalyzed decomposition of peroxynitrite anion (ONOO-), namely the peroxynitrite decomposition catalysts or as superoxide (O2 •-)-scavengers which are the functional mimetics of superoxide dismutase (SOD) enzymes (SODm), as well as the derivatives of 6-nitro-3,4-methylenedioxyphenyl-Nacylhydrazone (LASSBio-881) or γ-butyrolactone (LPP1, BM113, BM113A, BM138 and BM138A) are also discussed as potent and promising future heterocyclic analgesics.

  16. Structural characterization, vibrational spectroscopy accomplished with DFT calculation, thermal and dielectric behaviors in a new organic-inorganic tertrapropylammonium aquapentachlorostannate dihydrate compound

    Energy Technology Data Exchange (ETDEWEB)

    Hajlaoui, Sondes, E-mail: hajlaouisondes@yahoo.fr [Unité de recherche de la matière condensée, Faculté des Sciences de Sfax, Université de Sfax, BP 1171, 3000, Sfax (Tunisia); Chaabane, Iskandar [Unité de recherche de la matière condensée, Faculté des Sciences de Sfax, Université de Sfax, BP 1171, 3000, Sfax (Tunisia); Lhoste, Jérôme; Bulou, Alain [LUNAM Université, Université du Maine, CNRS UMR 6283, Institut des Molécules et Matériaux du Mans (IMMM), Avenue Olivier Messiaen, 72085, Le Mans, Cedex 9 (France); Guidara, Kamel [Unité de recherche de la matière condensée, Faculté des Sciences de Sfax, Université de Sfax, BP 1171, 3000, Sfax (Tunisia)

    2016-09-15

    In this work a novel compound tertrapropylammonium aquapentachlorostannate dihydrate was synthesized and characterized by; single crystal X-ray diffraction, vibrational spectroscopy, differential scanning calorimetric and dielectric measurement. The crystal structure refinement at room temperature reveled that this later belongs to the monoclinic compound with P121/c1 space group with the following unit cell parameters a = 8.2699(3) Å, b = 12.4665(4) Å, c = 22.3341(7) Å and β = 92.94(0)°. The crystal arrangement can be described by stacked organic-inorganic layers in the c direction with two independent water molecules placed between each two layers. The detailed interpretations of the vibrational properties of the studied compound were performed using density functional theory (DFT) with the B3LYP/LanL2DZ basis set, and has enabled us to make the detailed assignments by comparative study of the experimental and calculated Raman and IR spectra. The differential scanning calorimetry (DSC) measurement disclosed two anomalies in the temperature range 356–376 (T{sub 1}) K and at 393 K (T{sub 2}) characterized by the dehydration of the sample and probably a reconstruction of a new structure after T{sub 2} transition. The temperature dependences of dielectric permittivity show a relaxation process around T{sub 2} anomaly indicating the occurrence of the disorder at high temperature. The dependence of the exponent m(T) on temperature, extracted from the straight lines of log(ε″) with log (ω), suggests that the correlated barrier hopping is the appropriate model for the conduction mechanism. - Highlights: • The single-crystal X-ray diffraction has been performed. • The assignments of the vibration modes based on DFT were reported and discussed. • Differential scanning calorimetric reveals the presence of two endothermic peaks. • The electric permittivity was studied using the impedance measurements. • The CBH is the appropriate model for the conduction

  17. Synthesis, crystal structure and growth of a new inorganic- organic hybrid compound for nonlinear optical applications: Aquadiiodo (3-aminopropanoic acid) cadmium (II)

    Science.gov (United States)

    Boopathi, K.; Babu, S. Moorthy; Jagan, R.; Ramasamy, P.

    2017-12-01

    The new inorganic-organic hybrid material aquadiiodo (3-aminopropanoic acid) cadmium (II) [ADI (3-AP) Cd] has been successfully synthesized and good quality crystals have been grown by slow evaporation solution technique. The structure was determined by single crystal X-ray diffraction at room temperature. The compound crystallizes in monoclinic crystal system with centro symmetric space group P21/c and four molecules in the unit cell. The structure of the title compound was further confirmed by 1H and 13C nuclear magnetic resonance spectral analysis. FT-IR spectroscopy was used to confirm the presence of various functional groups in the compound. The transmittance and optical parameters of the crystal were studied by UV- Visible-NIR spectroscopy. The thermal stability of the grown crystal was evaluated using thermogravimetric and differential thermal analyses. Mechanical hardness has been identified by Vickers micro hardness study and work hardening coefficient was calculated. Dielectric measurement was carried out as a function of frequency and results are discussed. The growth mechanism of the crystal was assessed by chemical etching studies. The third-order nonlinear optical susceptibility of [ADI (3-AP) Cd] was derived using the Z-scan technique, and it was 3.24955 × 10-8 esu. The positive nonlinear refractive index 2.48505 × 10-11 m2/W, is an indication of self-defocusing optical nonlinearity of the sample. It is believed that the [ADI (3-AP) Cd] is a promising new candidate for developing efficient nonlinear optical and optical power limiting devices.

  18. Optimization of on-line hydrogen stable isotope ratio measurements of halogen- and sulfur-bearing organic compounds using elemental analyzer–chromium/high-temperature conversion isotope ratio mass spectrometry (EA-Cr/HTC-IRMS)

    Science.gov (United States)

    Gehre, Matthias; Renpenning, Julian; Geilmann, Heike; Qi, Haiping; Coplen, Tyler B.; Kümmel, Steffen; Ivdra, Natalija; Brand, Willi A.; Schimmelmann, Arndt

    2017-01-01

    Rationale: Accurate hydrogen isotopic analysis of halogen- and sulfur-bearing organics has not been possible with traditional high-temperature conversion (HTC) because the formation of hydrogen-bearing reaction products other than molecular hydrogen (H2) is responsible for non-quantitative H2 yields and possible hydrogen isotopic fractionation. Our previously introduced, new chromium-based EA-Cr/HTC-IRMS (Elemental Analyzer–Chromium/High-Temperature Conversion Isotope Ratio Mass Spectrometry) technique focused primarily on nitrogen-bearing compounds. Several technical and analytical issues concerning halogen- and sulfur-bearing samples, however, remained unresolved and required further refinement of the reactor systems.

  19. Trends in air concentration and deposition at background monitoring sites in Sweden - major inorganic compounds, heavy metals and ozone

    Energy Technology Data Exchange (ETDEWEB)

    Kindbom, K.; Svensson, Annika; Sjoeberg, K.; Pihl Karlsson, G.

    2001-09-01

    This report describes concentrations in air of sulphur compounds, soot, nitrogen compounds and ozone in Sweden between 1985-1998. Time trends of concentration in precipitation and deposition of sulphate, nitrate, ammonium, acidity, base cations and chloride in six different regions covering Sweden are evaluated during the period 1983-1998. Trends of heavy metals in precipitation have been analysed for the period 1983-1998 and the change in heavy metal concentration, 1975-1995, in mosses is described. Data used in the trend analyses originates from measurements performed at six Swedish EMEP stations and from approximately 25 stations within the national Precipitation Chemistry Network. Two different statistical methods, linear regression and the non-parametric Mann Kendall test, have been used to evaluate changes in annual mean values. Time trends of concentration of sulphur dioxide, particulate sulphate, soot, nitrogen dioxide, total nitrate and total ammonium in air show highly significant decreasing trends, except for soot at one station in northern Sweden. Concentrations of ozone have a strong seasonal variation with a peak occurring in spring every year. However, annual ozone concentrations show no obvious trends in spite of decreasing emissions of the precursors NOx and VOC. A slight indication of a decreasing trend in the number of ozone episodes might be seen from 1990 to 1998. Sulphate concentrations in precipitation and deposition show strongly significant decreasing trends in the whole country. Concentrations and deposition of nitrate and ammonium have been decreasing in all areas except for nitrate at stations in south-west and north-west Sweden and ammonium in south-west Sweden. Acidity has decreased in all areas since 1989, resulting in increasing pH values in Sweden. The interannual variations of concentration and deposition of base cations and chloride are large and few general trends can be seen during 1983-1997. Time trends of four heavy metals in

  20. Physiology and genetics of sulfur-oxidizing bacteria.

    Science.gov (United States)

    Friedrich, C G

    1998-01-01

    Reduced inorganic sulfur compounds are oxidized by members of the domains Archaea and Bacteria. These compounds are used as electron donors for anaerobic phototrophic and aerobic chemotrophic growth, and are mostly oxidized to sulfate. Different enzymes mediate the conversion of various reduced sulfur compounds. Their physiological function in sulfur oxidation is considered (i) mostly from the biochemical characterization of the enzymatic reaction, (ii) rarely from the regulation of their formation, and (iii) only in a few cases from the mutational gene inactivation and characterization of the resulting mutant phenotype. In this review the sulfur-metabolizing reactions of selected phototrophic and of chemotrophic prokaryotes are discussed. These comprise an archaeon, a cyanobacterium, green sulfur bacteria, and selected phototrophic and chemotrophic proteobacteria. The genetic systems are summarized which are presently available for these organisms, and which can be used to study the molecular basis of their dissimilatory sulfur metabolism. Two groups of thiobacteria can be distinguished: those able to grow with tetrathionate and other reduced sulfur compounds, and those unable to do so. This distinction can be made irrespective of their phototrophic or chemotrophic metabolism, neutrophilic or acidophilic nature, and may indicate a mechanism different from that of thiosulfate oxidation. However, the core enzyme for tetrathionate oxidation has not been identified so far. Several phototrophic bacteria utilize hydrogen sulfide, which is considered to be oxidized by flavocytochrome c owing to its in vitro activity. However, the function of flavocytochrome c in vivo may be different, because it is missing in other hydrogen sulfide-oxidizing bacteria, but is present in most thiosulfate-oxidizing bacteria. A possible function of flavocytochrome c is discussed based on biophysical studies, and the identification of a flavocytochrome in the operon encoding enzymes involved

  1. Ring opening of azetidine cycle: First examples of 1-azetidinepropanamine molecules as a template in hybrid organic-inorganic compounds

    Science.gov (United States)

    Gurzhiy, Vladislav V.; Tyumentseva, Olga S.; Britvin, Sergey N.; Krivovichev, Sergey V.; Tananaev, Ivan G.

    2018-01-01

    Three novel uranyl selenate and sulfate oxysalts templated by protonated azetidine molecules, [AzH]+, and its ring-opened counterpart 1-azetidinepropanamine, [AzH(CH2)3NH3]2+, have been prepared and studied by X-ray structural analysis. Conformations of azetidinium cations were analysed by means of infrared vibrational assignments supported by the DFT calculations. Crystallization of [AzH]2 [(UO2)2(SeO4)3(H2O)] (I) from highly acidic solutions suggests that low pH does not necessarily result in the opening of azetidine ring. [AzH(CH2)3NH3][(UO2)2(SeO4)3(H2O)](H2O) (II) and [AzH(CH2)3NH3](H5O2)[(UO2)2(SO4)3(HSO4)] (III) are the first structurally characterized crystalline compounds bearing isolated ring-opened azetidine moiety.

  2. Discrimination and risk assessment due to the volatile compounds and the inorganic elements present in the Greek marc distillates Tsipouro and Tsikoudia

    Directory of Open Access Journals (Sweden)

    Evangelos H. Soufleros

    2005-03-01

    Full Text Available Tsipouro and Tsikoudia are two denominations with geographic indications of the traditional Greek marc distillate, which is produced in continental Greece and in the island of Crete respectively. It is produced by the Greek winegrowers as well as by the professional distillers. To provide data on the safety of domestic Tsipouro and Tsikoudia distillates for human consumption and to draw conclusions from any essential results, which might have an impact on the quality of this product, 23 samples were analysed for: (a Volatile compounds by the use of gas chromatography, (b Inorganic elements, using atomic absorption spectrometry and (c the pH values through-out using standard methods. Data revealed differences between these two denominations, which have been confirmed by the application of a statistic analysis and a PCA. Thus, Tsikoudia was found to contain statistically higher amounts of acetalde-hyde. However, the levels that have been observed did not exceed the official limits. Most of the Tsipouro and Tsikoudia samples also contained low concentrations of estragol, an anise compound, lead and copper, which do not represent a risk to consumer health due to their toxicity. On the other hand, the total concentration of higher alcohols was higher than the official minimum limit (140 g.hl-1 Absolute Alcohol-AA, while the amylic alcohols rarely exceeded 300 g.hl-1 AA. The high concentrations of ethyl acetate (>300 g.hl-1 AA and ethyl lactate in a few samples showed the necessity of limiting unwanted fermentations in the grape pomace. The analytical study showed that the quality of the marc distillate is, generally, satisfactory. However, it revealed great differences between Tsipouro and Tsikoudia even among the samples of each denomination and, con-sequently, these domestic distillates need standardization and a more systematic production.

  3. Preparation of polymeric fibers immobilizing inorganic compounds, enzymes, and extractants designed for radionuclide decontamination, ultrapure water production, and rare-earth metal purification

    International Nuclear Information System (INIS)

    Saito, Kyoichi

    2014-01-01

    To remove and recover targeted ions and molecules at a high rate, inorganic compounds, enzymes, and extractants were immobilized onto a commercially available 6-nylon fiber by radiation-induced graft polymerization and subsequent chemical modifications. Fibrous supports with a smaller diameter provide a larger external interface area with liquids. Modified fibers are fabricated into various shapes such as wound filter and braid according to application sites. First, insoluble cobalt ferrocyanide-impregnated fiber was prepared via precipitation by immersing ferrocyanide ion-bound anion-exchange fiber in cobalt chloride solution. Cobalt ferrocyanide impregnated onto the polymer chain grafted onto the fiber specifically captured cesium ions in seawater. Similarly, sodium titanate impregnated onto a cation-exchange fiber selectively captured strontium ions in seawater. Second, urease was bound by an anion-exchange graft chain, followed by enzymatic cross-linking among urease molecules with transglutaminase. The bed charged with the urease-immobilized fiber exhibited a quantitative hydrolysis of urea at a high space velocity of urea solution. Third, an acidic extractant (HDEHP, bis(2-ethylhexyl) phosphate) was impregnated onto a dodecylamino-group-containing polymer chain grafted onto the 6-nylon fiber. Distribution coefficients of the HDEHP-impregnated fiber for neodymium and dysprosium agreed well with those in n-dodecane. (author)

  4. Methods development for separation of inorganic anions, organic acids and bases, and neutral organic compounds by ion chromatography and capillary electrophoresis

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jie [Iowa State Univ., Ames, IA (United States)

    1999-04-01

    A novel anion-exchange resin containing three amine groups was prepared by reaction of a chloromethylated polystyrene-divinylbenzene (PS-DVB) resin with diethylenetriamine. After being protonated by contact with an aqueous acid, this resin can be used for ion chromatographic separation of anions. The charge on the resins can be varied from +1 to +3 by changing the mobile phase pH. The selectivity of the new ion exchangers for various inorganic anions was quite different from that of conventional anion exchangers. The performance of this new anion exchanger was studied by changing the pH and the concentration of the eluent, and several different eluents were used with some common anions as testing analytes. Conductivity detection and UV-visible detection were applied to detect the anions after separation. The new resin can also be used for HPLC separation of neutral organic compounds. Alkylphenols and alkylbenzenes were separated with this new polymeric resin, and excellent separations were obtained under simple conditions. This report contains Chapter 1: General introduction and Chapter 6: General conclusions.

  5. Room-temperature polar order in [NH4][Cd(HCOO)3]--a hybrid inorganic-organic compound with a unique perovskite architecture.

    Science.gov (United States)

    Gómez-Aguirre, L C; Pato-Doldán, B; Stroppa, A; Yáñez-Vilar, S; Bayarjargal, L; Winkler, B; Castro-García, S; Mira, J; Sánchez-Andújar, M; Señarís-Rodríguez, M A

    2015-03-02

    We report on the hybrid inorganic-organic ammonium compound [NH4][Cd(HCOO)3], which displays a most unusual framework structure: instead of the expected 4(9)·6(6) topology, it shows an ABX3 perovskite architecture with the peculiarity and uniqueness (among all the up-to-date reported hybrid metal formates) that the Cd ions are connected only by syn-anti formate bridges, instead of anti-anti ones. This change of the coordination mode of the formate ligand is thus another variable that can provide new possibilities for tuning the properties of these versatile functional metal-organic framework materials. The room-temperature crystal structure of [NH4][Cd(HCOO)3] is noncentrosymmetric (S.G.: Pna21) and displays a polar axis. DFT calculations and symmetry mode analysis show that the rather large polarization arising from the off-center shift of the ammonium cations in the cavities (4.33 μC/cm(2)) is partially canceled by the antiparallel polarization coming from the [Cd(HCOO)3](-) framework, thus resulting in a net polarization of 1.35 μC/cm(2). As shown by second harmonic generation studies, this net polarization can be greatly increased by applying pressure (Pmax = 14 GPa), an external stimulus that, in turn, induces the appearance of new structural phases, as confirmed by Raman spectroscopy.

  6. A three-electrode column for Pd-catalytic oxidation of TCE in groundwater with automatic pH-regulation and resistance to reduced sulfur compound foiling.

    Science.gov (United States)

    Yuan, Songhu; Chen, Mingjie; Mao, Xuhui; Alshawabkeh, Akram N

    2013-01-01

    A hybrid electrolysis and Pd-catalytic oxidation process is evaluated for degradation of trichloroethylene (TCE) in groundwater. A three-electrode, one anode and two cathodes, column is employed to automatically develop a low pH condition in the Pd vicinity and a neutral effluent. Simulated groundwater containing up to 5 mM bicarbonate can be acidified to below pH 4 in the Pd vicinity using a total of 60 mA with 20 mA passing through the third electrode. By packing 2 g of Pd/Al(2)O(3) pellets in the developed acidic region, the column efficiency for TCE oxidation in simulated groundwater (5.3 mg/L TCE) increases from 44 to 59 and 68% with increasing Fe(II) concentration from 0 to 5 and 10 mg/L, respectively. Different from Pd-catalytic hydrodechlorination under reducing conditions, this hybrid electrolysis and Pd-catalytic oxidation process is advantageous in controlling the fouling caused by reduced sulfur compounds (RSCs) because the in situ generated reactive oxidizing species, i.e., O(2), H(2)O(2) and OH, can oxidize RSCs to some extent. In particular, sulfite at concentrations less than 1 mM even greatly increases TCE oxidation by the production of SO(4)(•-), a strong oxidizing radical, and more OH. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Effects of Reduced Sulfur Compounds on Pd-catalytic Hydrodechlorination of TCE in Groundwater by Cathodic H2 under Electrochemically-induced Oxidizing Conditions

    Science.gov (United States)

    Yuan, Songhu; Chen, Mingjie; Mao, Xuhui; Alshawabkeh, Akram N.

    2014-01-01

    Reduced sulfur compounds (RSCs) poison Pd catalysts for catalytic hydrodechlorination of contaminants in anoxic groundwater. This study investigates the effects of RSCs on Pd-catalytic hydrodechlorination of trichloroethylene (TCE) in oxic groundwater. Water electrolysis in an undivided electrolytic cell is used to produce H2 for TCE hydrodechlorination under oxidizing conditions. TCE is efficiently hydrodechlorinated to ethane, with significant accumulation of H2O2 under acidic conditions. Presence of sulfide at concentrations less than 93.8 μM moderately inhibits TCE hydrodechlorination and H2O2 production. Presence of sulfite at low concentrations (≤ 1 mM) significantly enhances TCE decay, while at high concentration (3 mM) inhibits initially and enhances afterwards when sulfite concentration declines to less than 1 mM. Using radical scavenging experiments and electron spin resonance assay, SO3•− which is generated from sulfite under oxidizing conditions is validated as the new reactive species contributing to the enhancement. This study reveals a distinct mechanism of effect of sulfite on TCE hydrodechlorination by Pd and H2 in oxic groundwater and presents an alternative approach to increasing resistance of Pd to RSCs poisoning. PMID:23962132

  8. An Approach for Measuring the Sorptive Behavior of Odorants Using a Multifunction Thermal Desorber Unit: Preliminary Tests on Reduced Sulfur Compounds

    Directory of Open Access Journals (Sweden)

    Sang-Woo Joo

    2008-03-01

    Full Text Available In this study, the sorptive behavior of reduced sulfur compounds (RSC was investigated using a combination of thermal desorber (TD unit and gas chromatography (GC. To examine the sorptive properties of RSC on textile materials, two types of experiments were conducted under experimental conditions favorable for sorptive processes. In all the experiments, gaseous standards of hydrogen sulfide, methanethiol, dimethyl sulfide, and dimethyl disulfide were supplied to initiate the adsorption processes on textile pieces. The textile pieces were then forced to release those adsorbed RSC under a fixed condition. It was found that the extent of adsorption, if evaluated quantitatively, occurred at approximately 1/1000 to 1/100 of the level of RSC standards supplied originally to induce adsorption. It also indicated that RSC adsorption was affected very sensitively by the initial exposure durations to induce RSC adsorption with an exponential decrease in relative recovery (RR values with increasing exposure time. The relative sorptive patterns, when compared between different RSCs, were affected most sensitively by such factors as molecular weight and/or physical contact conditions.

  9. Participation of oxidized sulfur center in intramolecular free radical processes in the model organic compounds of biological importance

    International Nuclear Information System (INIS)

    Pogocki, D.M.

    2004-01-01

    The pathogenesis of neurodegenerative diseases such as prion diseases (Creutzfeldt-Jacob disease) and Alzheimer's disease is strongly associated with the presence of β-amyloid peptide (βA) and prion protein (hPrP) in the brain tissue. Both macromolecules contain methionine (Met) residues. Their presence seems to be responsible for unique redox properties of βA and hPrP. These residues may undergo relatively easy autooxidation and/or metal-catalysed oxidation. The presented studies were focused on the potential function of Met residues as antioxidants or pro-oxidants and on their role in radical-mediated oxidation of peptides and proteins. The role of S-, O-, N- and C-centered radicals generated in various oligopeptides containing Met and relevant model compounds has been examined in detail with respect to formation of 2c-3e bonds, redox processes, fragmentation and their mutual interconversion. In order to achieve these goals several experimental radiation, photochemical, and molecular modelling methods were applied. The experimental and molecular modelling results show significant influence of functional neighbouring groups and conformational flexibility of a peptide backbone on the oxidative reduction pathway in oligopeptides containing single and multiple Met residues. The results presented here allow for better understanding of the known propensities of βA and hPrP to reduce transition metals and to form reactive oxygen species and free radicals. (author)

  10. Chemical characteristics of size-resolved atmospheric aerosols in Iasi, north-eastern Romania: nitrogen-containing inorganic compounds control aerosol chemistry in the area

    Science.gov (United States)

    Giorgiana Galon-Negru, Alina; Iulian Olariu, Romeo; Arsene, Cecilia

    2018-04-01

    This study assesses the effects of particle size and season on the content of the major inorganic and organic aerosol ionic components in the Iasi urban area, north-eastern Romania. Continuous measurements were carried out over 2016 using a cascade Dekati low-pressure impactor (DLPI) performing aerosol size classification in 13 specific fractions over the 0.0276-9.94 µm size range. Fine-particulate Cl-, NO3-, NH4+, and K+ exhibited clear minima during the warm season and clear maxima over the cold season, mainly due to trends in emission sources, changes in the mixing layer depth and specific meteorological conditions. Fine-particulate SO42- did not show much variation with respect to seasons. Particulate NH4+ and NO3- ions were identified as critical parameters controlling aerosol chemistry in the area, and their measured concentrations in fine-mode (PM2.5) aerosols were found to be in reasonable good agreement with modelled values for winter but not for summer. The likely reason is that NH4NO3 aerosols are lost due to volatility over the warm season. We found that NH4+ in PM2.5 is primarily associated with SO42- and NO3- but not with Cl-. Actually, indirect ISORROPIA-II estimations showed that the atmosphere in the Iasi area might be ammonia rich during both the cold and warm seasons, enabling enough NH3 to be present to neutralize H2SO4, HNO3, and HCl acidic components and to generate fine-particulate ammonium salts, in the form of (NH4)2SO4, NH4NO3, and NH4Cl. ISORROPIA-II runs allowed us to estimate that over the warm season ˜ 35 % of the total analysed samples had very strongly acidic pH (0-3), a fraction that rose to ˜ 43 % over the cold season. Moreover, while in the cold season the acidity is mainly accounted for by inorganic acids, in the warm ones there is an important contribution by other compounds, possibly organic. Indeed, changes in aerosol acidity would most likely impact the gas-particle partitioning of semi-volatile organic acids. Overall, we

  11. Inorganic liquid scintillator

    International Nuclear Information System (INIS)

    Pavlicek, Z.; Barta, C.; Jursova, L.

    1986-01-01

    An inorganic liquid scintillator is designed which contains 1 to 30 wt.% of an inorganic molecular compound as the basic active component; the compound contains a cation with an atomic number higher than 47 and a halogen anion. The basic inorganic component is dissolved in water or in an organic solvent in form of non-dissociated molecules or self-complexes in which the bond is preserved between the cation and anion components. The light yield from these scintillators ranges between 70 and 150% of the light yield of a standard organic scintillator based on toluene. They are advantageous in that that they allow to increase the water content in the sample to up to 100%. (M.D.)

  12. Method of distillation of sulfurous bituminous shales

    Energy Technology Data Exchange (ETDEWEB)

    Hallback, A J.S.; Bergh, S V

    1918-04-22

    A method of distillation of sulfur-containing bituminous shales is characterized by passing the hot sulfur-containing and oil-containing gases and vapors formed during the distillation through burned shale containing iron oxide, so that when these gases and vapors are thereafter cooled they will be, as far as possible, free from sulfur compounds. The patent contains six more claims.

  13. Hydrogen sulfide in plants: from dissipation of excess sulfur to signaling molecule.

    Science.gov (United States)

    Calderwood, Alexander; Kopriva, Stanislav

    2014-09-15

    Sulfur is essential in all organisms for the synthesis of amino acids cysteine and methionine and as an active component of numerous co-factors and prosthetic groups. However, only plants, algae, fungi, and some prokaryotes are capable of using the abundant inorganic source of sulfur, sulfate. Plants take sulfate up, reduce it, and assimilate into organic compounds with cysteine being the first product of the pathway and a donor of reduced sulfur for synthesis of other S-containing compounds. Cysteine is formed in a reaction between sulfide, derived from reduction of sulfite and an activated amino acid acceptor, O-acetylserine. Sulfide is thus an important intermediate in sulfur metabolism, but numerous other functions in plants has been revealed. Hydrogen sulfide can serve as an alternative source of sulfur for plants, which may be significant in anaerobic conditions of waterlogged soils. On the other hand, emissions of hydrogen sulfide have been detected from many plant species. Since the amount of H2S discharged correlated with sulfate supply to the plants, the emissions were considered a mechanism for dissipation of excess sulfur. Significant hydrogen sulfide emissions were also observed in plants infected with pathogens, particularly with fungi. H2S thus seems to be part of the widely discussed sulfur-induced-resistance/sulfur-enhanced-defense. Recently, however, more evidence has emerged for a role for H2S in regulation and signaling. Sulfide stabilizes the cysteine synthase complex, increasing so the synthesis of its acceptor O-acetylserine. H2S has been implicating in regulation of plant stress response, particularly draught stress. There are more and more examples of processes regulated by H2S in plants being discovered, and hydrogen sulfide is emerging as an important signaling molecule, similar to its role in the animal and human world. How similar the functions, and homeostasis of H2S are in these diverse organisms, however, remains to be elucidated

  14. Radionuclides, inorganic constitutents, organic compounds, and bacteria in water from selected wells and springs from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman Area, Idaho, 1992

    International Nuclear Information System (INIS)

    Bartholomay, R.C.; Edwards, D.D.; Campbell, L.J.

    1994-01-01

    The U.S. Geological Survey and the Idaho Department of Water Resources, in response to a request from the U.S. Department of Energy, sampled 18 sites as part of a long-term project to monitor water quality of the Snake River Plain aquifer from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman area. Water samples were collected and analyzed for selected radionuclides, inorganic constituents, organic compounds, and bacteria. The samples were collected from 13 irrigation wells, 1 domestic well, 1 spring, 2 stock wells, and 1 public supply well. Quality assurance samples also were collected and analyzed. None of the samples analyzed for radionuclides, inorganic constituents, or organic compounds exceeded the established maximum contaminant levels for drinking water. Most of the radionuclide and inorganic constituent concentrations exceeded their respective reporting levels. Most of the samples analyzed for surfactants and dissolved organic carbon had concentrations that exceeded their reporting levels. None of the samples contained reportable concentrations of purgeable organic compounds or pesticides. Total coliform bacteria was present in nine samples

  15. Inorganic elements and organic compounds degradation studies by gamma irradiation in used lubricating oils; Estudos de remocao de elementos inorganicos e degradacao de compostos organicos por radiacao gama em oleos lubrificantes usados

    Energy Technology Data Exchange (ETDEWEB)

    Scapin, Marcos Antonio

    2008-07-01

    The automotive lubricating oils have partial degradation of organic compounds and addition of undesirable inorganic elements, during its use. These substances classify the used lubricating oils as dangerous and highly toxic. According to global consensus, concerning the environmental conservation, the best is to perform a reuse treatment of these lubricating oils. For this purpose, the uses of an alternative and effective technology have been sought. In this work, the efficacy and technical feasibility of the advanced oxidation process (AOP), by gamma radiation, for used automotive lubricating oil treatment has been studied. Different quantities of hydrogen peroxide and water Milli-Q were added to oil samples. They were submitted to the Cobalt-60 irradiator, type Gammacell, with 100, 200 and 500 kGy absorbed doses. The inorganic analysis by X-ray fluorescence (WDXRF) showed inorganic elements removal, mainly to sulphur, calcium, iron and nickel elements at acceptable levels by environmental protection law for oils reusing. The gas chromatography (GC/MS) analysis showed that the advanced oxidation process promotes the organic compounds degradation. The main identified compounds were tridecane, 2-methyl-naphthalene, and trietilamina-tetramethyl urea, which have important industrial applications. The multivariate analysis, Cluster Analysis, showed that advanced oxidation process application is a viable and promising treatment for used lubricating oil reusing. (author)

  16. Interactions between bicarbonate, potassium, and magnesium, and sulfur-dependent induction of luminescence in Vibrio fischeri.

    Science.gov (United States)

    Tabei, Yosuke; Era, Mariko; Ogawa, Akane; Morita, Hiroshi

    2012-06-01

    In spite of its central importance in research efforts, the relationship between seawater compounds and bacterial luminescence has not previously been investigated in detail. Thus, in this study, we investigated the effect of cations (Na(+) , K(+) , NH(4) (+) , Mg(2+) , and Ca(2+) ) and anions (Cl(-) , HCO(3) (-) , CO(3) (2-) , and NO(3) (-) ) on the induction of both inorganic (sulfate, sulfite, and thiosulfate) and organic (L-cysteine and L-cystine) sulfur-dependent luminescence in Vibrio fischeri. We found that HCO(3) (-) (bicarbonate) and CO(3) (2-) (carbonate), in the form of various compounds, had a stimulatory effect on sulfur-dependent luminescence. The luminescence induced by bicarbonate was further promoted by the addition of magnesium. Potassium also increased sulfur-dependent luminescence when sulfate or thiosulfate was supplied as the sole sulfur source, but not when sulfite, L-cysteine, or L-cystine was supplied. The positive effect of potassium was accelerated by the addition of magnesium and/or calcium. Furthermore, the additional supply of magnesium improved the induction of sulfite- or L-cysteine-dependent luminescence, but not the l-cystine-dependent type. These results suggest that sulfur-dependent luminescence of V. fischeri under nutrient-starved conditions is mainly controlled by bicarbonate, carbonate, and potassium. In addition, our results indicate that an additional supply of magnesium is effective for increasing V. fischeri luminescence. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Catalysts for liquid phase oxidation of olefins and sulfur compounds; Catalyseurs pour l'oxydation en phase liquide d'olefines et de composes soufres

    Energy Technology Data Exchange (ETDEWEB)

    Palomeque Santiago, J.F.

    2002-07-01

    Several basic, acid and acid-base catalysts were studied for the epoxidation of olefins activated or not and dibenzo-thiophene.Hydrotalcite activation by thermic treatment and in situ re-hydration improves catalytic activity for 2-cyclohexene-1-one and isophorone. Bronsted basic sites were found to be more active than Lewis sites. Total conversion of 2-cyclohexene-1-one is reached in 1.5 h in polar solvents. W{sub 7}O{sub 24}{sup 6-} Iso-poly-anion was exchanged onto a meixnerite by a new preparation method, A meso-porous solid was obtained with good catalytic properties for cyclohexene epoxidation 100% selective to epoxide. W{sub 7}O{sub 24}{sup 6-} and WO{sub 5}{sup 2-} anions and phenyl and dodecyl-phospho-tungstates were grafted on hydrotalcites. Due to the acid-base characteristics of these solid catalysts, cyclohexene yields products of allylic reactions. Mg-La, and Mg-Al-La mixed oxides were synthesized and mixed phases were gotten. Their basic characteristics account for hydrogen peroxide decomposition which prevents DBT oxidation reaction to sulfone. On the contrary, Mg-Al re-hydrated hydrotalcites are very active for this reaction and remove 100% of sulfur compounds in 1 hour. New catalyst W-ZrO{sub 2} were synthesized with high acid properties. stable structure with temperature and high DBT conversion in less than 5 minutes of reaction. These catalytic systems can be applied for hydrocarbon desulfurization of fuels like naphtha, gas oil and kerosene. (author)

  18. Hot and Dry Cleaning of Biomass-Gasified Gas Using Activated Carbons with Simultaneous Removal of Tar, Particles, and Sulfur Compounds

    Directory of Open Access Journals (Sweden)

    Kinya Sakanishi

    2012-05-01

    Full Text Available This study proposes a gas-cleaning process for the simultaneous removal of sulfur compounds, tar, and particles from biomass-gasified gas using Fe-supported activated carbon and a water-gas shift reaction. On a laboratory scale, the simultaneous removal of H2S and COS was performed under a mixture of gases (H2/CO/CO2/CH4/C2H4/N2/H2S/COS/steam. The reactions such as COS + H2 → H2S + CO and COS + H2O → H2S + CO2 and the water-gas shift reaction were promoted on the Fe-supported activated carbon. The adsorption capacity with steam was higher than that without steam. On a bench scale, the removal of impurities from a gas derived from biomass gasification was investigated using two activated filters packed with Fe-supported activated carbon. H2S and COS, three- and four-ring polycyclic aromatic hydrocarbons (PAHs, and particles were removed and a water-gas shift reaction was promoted through the first filter at 320–350 °C. The concentrations of H2S and COS decreased to less than 0.1 ppmv. Particles and the one- and two-ring PAHs, except for benzene, were then removed through the second filter at 60–170 °C. The concentration of tar and particles decreased from 2428 to 102 mg Nm−3 and from 2244 to 181 mg Nm−3, respectively.

  19. Investigation of the influence of liquid water films on O3 and PAN deposition on plant leaf surfaces treated with organic / inorganic compounds

    Science.gov (United States)

    Sun, Shang; Moravek, Alexander; von der Heyden, Lisa; Held, Andreas; Kesselmeier, Jürgen; Sörgel, Matthias

    2016-04-01

    Liquid water films on environmental surfaces play an important role in various fields of interest (Burkhardt and Eiden, 1994). For example, the deposition of water soluble trace gases could be increased by surface moisture. Chameides and Stelson (1992) found out that the dissolution of trace gases in airborne particulate matter increases with rising water/solid ratio of the particles. Further, Flechard et al. (1999) concluded that deliquescent salt particles represent a potential sink for trace gases, depending on their chemical property. The formation of surface water films and its influence on the gas deposition was proposed by many previous studies (Fuentes and Gillespie, 1992, Burkhardt and Eiden, 1994, van Hove et al., 1989, Burkhardt et al., 1999, Flechard et al., 1999). In this study we investigate the influence of leaf surface water films on the deposition of O3 and PAN under controlled laboratory conditions. A twin cuvette system described in Sun et al. (2015) was used to control the environmental parameters such as light, temperature, trace gas mixing ratio and humidity. Furthermore, the leaf surface was treated with various organic and inorganic solutions to investigate the influence of deposited compounds on the electrical surface conductance of the leaves and the surface deposition of O3 and PAN at various relative humidities. The result shows that RHcrit, where the electrical surface conductance (G) increases exponentially, was 40 % during the light period and 50 % during the dark period. Furthermore, we observed that the formation of the leaf surface liquid film was depended on the deposited compounds on the leaf cuticles. For the O3 deposition on plants (Quercus ilex) a clear enhancement at rising environmental air humidity under light and dark condition was found. The increase during light conditions can be related partly to increasing stomatal conductance with higher RH. From the non-stomatal deposition measured in dark experiments, we could

  20. Thermochromic Fluorescence from B18H20(NC5H5)(2): An Inorganic-Organic Composite Luminescent Compound with an Unusual Molecular Geometry

    Czech Academy of Sciences Publication Activity Database

    Londesborough, Michael Geoffrey Stephen; Dolanský, Jiří; Cerdán, L.; Lang, Kamil; Jelínek, Tomáš; Oliva, J. M.; Hnyk, Drahomír; Roca-Sanjuan, D.; Frances-Monerris, A.; Martinčík, Jiří; Nikl, Martin; Kennedy, John David

    2017-01-01

    Roč. 5, č. 6 (2017), č. článku UNSP 1600694. ISSN 2195-1071 R&D Projects: GA ČR(CZ) GA13-09876S Institutional support: RVO:61388980 ; RVO:68378271 Keywords : boranes * energy transfer * fluorescence * solar concentrators * thermochromicity Subject RIV: CA - Inorganic Chemistry ; BH - Optics, Masers, Lasers (FZU-D) OBOR OECD: Inorganic and nuclear chemistry ; Optics (including laser optics and quantum optics) (FZU-D) Impact factor: 6.875, year: 2016

  1. Phosphorus, sulfur and pyridine

    OpenAIRE

    Schönberger, Stefanie

    2013-01-01

    The synthesis of distinct neutral or anionic P,S compounds in solution provides a great challenge for chemists. Due to the similarity in the energies of the P–P, P–S and S–S bonds nearly solely a mixture of compounds with different composition and charge is obtained. Our interest focuses on the system consisting of phosphorus, sulfur and pyridine, with the aim of a greater selectivity of P,S compounds in solution. The combination of these three components offers the opportunity...

  2. Effects of anti-inflammatory compounds on sulfur mustard injured cells: Recommendations and caveats suggested by in vitro cell culture models.

    Science.gov (United States)

    Menacher, Georg; Steinritz, Dirk; Schmidt, Annette; Popp, Tanja; Worek, Franz; Gudermann, Thomas; Thiermann, Horst; Balszuweit, Frank

    2018-09-01

    Sulfur mustard (SM) is a vesicant agent who had its first military use 100 years ago, in Ypres. Since then it has been used in several conflicts like the Iran-Iraq war in the 1980s. The use of SM in Syria 2015 indicated the still existing threat. Despite decades of research no causal antidote against SM intoxication is available, so far. A SM intoxication is accompanied by necrosis, apoptosis and inflammation. To counteract the SM-induced inflammation, glucocorticoids and non-steroidal anti-inflammatory compounds (NSAIDs) are recommended. Aim of this study was to evaluate the efficacy of the anti-inflammatory compounds dexamethasone, ibuprofen and diclofenac in vitro. For that purpose, two different cell culture models were used. Firstly, a monoculture of keratinocytes (HaCaT) and secondly, an established co-culture of keratinocytes (HaCaT) and immunocompetent cells (THP-1) to identify the role of immune cells in the process and to mimic the dermal physiology more closely. Both models were challenged with different SM concentrations (100, 200 and 300μM) and treated with different anti-inflammatory compounds one hour after the SM exposure. Analytical analysis of necrosis (ToxiLight), apoptosis (CDDE) and inflammation (IL-6 and -8 ELISAs) followed 24h thereafter. Dexamethasone provided small but consistent protective effects in the monoculture. For the reduction of apoptosis, 3μM dexamethasone was sufficient. The most effective reduction regarding interleukin (IL) production was found with 6μM dexamethasone. Protective effects were less pronounced in co-culture, which implies, that the protective effects of dexamethasone are rather generic and not due to a modulation of the immune cells. Against our expectations, ibuprofen strongly amplified apoptosis and necrosis in SM exposed cells in the monoculture as well as the co-culture. Therefore, use of ibuprofen for treatment of SM intoxication should at least be considered most critically, if not even regarded as

  3. Radionuclides, stable isotopes, inorganic constituents, and organic compounds in water from selected wells and springs from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman area, Idaho, 1993

    Science.gov (United States)

    Bartholomay, Roy C.; Edwards, Daniel D.; Campbell, Linford J.

    1994-01-01

    The U.S. Geological Survey and the Idaho Department of Water Resources, in response to a request from the U.S. Department of Energy, sampled 19 sites as part of a long-term project to monitor water quality of the Snake River Plain aquifer from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman area. Water samples were collected and analyzed for selected radionuclides, stable isotopes, inorganic constituents, and organic compounds. The samples were collected from seven irrigation wells, four domestic wells, two springs, one stock well, three dairy wells, one observation well, and one commercial well. Two quality assurance samples also were collected and analyzed. None of the radionuclides, inorganic constituents, or organic compounds exceeded the established maximum contaminant levels for drinking water. Most of the radionuclide and inorganic constituent concen- trations exceeded their respective laboratory reporting levels. All samples analyzed for surfactants and dissolved organic carbon had concentrations that exceeded their reporting level. Ethylbenzene concentrations exceeded the reporting level in one water sample.

  4. Evaluation of Toxicological Effects of an Aqueous Extract of Shells from the Pecan Nut Carya illinoinensis (Wangenh.) K. Koch and the Possible Association with Its Inorganic Constituents and Major Phenolic Compounds.

    Science.gov (United States)

    Porto, Luiz Carlos S; da Silva, Juliana; Sousa, Karen; Ambrozio, Mariana L; de Almeida, Aline; Dos Santos, Carla Eliete I; Dias, Johnny F; Allgayer, Mariangela C; Dos Santos, Marcela S; Pereira, Patrícia; Ferraz, Alexandre B F; Picada, Jaqueline N

    2016-01-01

    Background. Industrial processing of the pecan nut Carya illinoinensis K. Koch generated a large amount of shells, which have been used to prepare nutritional supplements and medicinal products; however, the safe use of shells requires assessment. This study evaluated the toxic, genotoxic, and mutagenic effects of pecan shell aqueous extract (PSAE) and the possible contribution of phenolic compounds, ellagic and gallic acids, and inorganic elements present in PSAE to induce toxicity. Results. Levels of inorganic elements like K, P, Cl, and Rb quantified using the Particle-Induced X-Ray Emission method were higher in PSAE than in pecan shells, while Mg and Mn levels were higher in shells. Mice showed neurobehavioral toxicity when given high PSAE doses (200-2,000 mg kg(-1)). The LD50 was 1,166.3 mg kg(-1). However, PSAE (50-200 mg·kg(-1)) and the phenolic compounds (10-100 mg·kg(-1)) did not induce DNA damage or mutagenicity evaluated using the comet assay and micronucleus test. Treatment with ellagic acid (10-100 mg·kg(-1)) decreased triglyceride and glucose levels, while treatments with PSAE and gallic acid had no effect. Conclusion. Pecan shell toxicity might be associated with high concentrations of inorganic elements such as Mn, Al, Cu, and Fe acting on the central nervous system, besides phytochemical components, suggesting that the definition of the safe dose should take into account the consumption of micronutrients.

  5. Radionuclides, inorganic constituents, organic compounds, and bacteria in water from selected wells and springs from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman Area, Idaho, 1990

    International Nuclear Information System (INIS)

    Bartholomay, R.C.; Edwards, D.D.; Campbell, L.J.

    1992-03-01

    The US Geological Survey and the Idaho Department of Water Resources, in response to a request from the US Department of Energy, sampled 19 sites as part of a long-term project to monitor water quality of the Snake River Plain aquifer from the southern boundary of the Idaho National Engineering Laboratory to the Hagerman area. Water samples were collected and analyzed for manmade pollutants and naturally occurring constituents. The samples were collected from seven irrigation wells, five domestic wells, two springs, one stock well, two dairy wells, one observation well, and one commercial well. Two quality assurance samples also were collected and analyzed. The water samples were analyzed for selected radionuclides, inorganic constituents, organic compounds, and bacteria. None of the radionuclides, inorganic constituents, or organic compounds exceeded the established maximum contaminant levels for drinking water. Most of the radionuclide and inorganic constituent concentrations exceeded their respective reporting levels. All samples analyzed for surfactants and dissolved organic carbon had concentrations that exceeded their reporting level. Toluene concentrations exceeded the reporting level in one water sample. Two samples contained fecal coliform bacteria counts that exceeded established maximum contaminant levels for drinking water

  6. Lithium sulfur batteries and electrolytes and sulfur cathodes thereof

    Science.gov (United States)

    Visco, Steven J.; Goncharenko, Nikolay; Nimon, Vitaliy; Petrov, Alexei; Nimon, Yevgeniy S.; De Jonghe, Lutgard C.; Katz, Bruce D.; Loginova, Valentina

    2017-05-23

    Lithium sulfur battery cells that use water as an electrolyte solvent provide significant cost reductions. Electrolytes for the battery cells may include water solvent for maintaining electroactive sulfur species in solution during cell discharge and a sufficient amount of a cycle life-enhancing compound that facilitates charging at the cathode. The combination of these two components enhances one or more of the following cell attributes: energy density, power density and cycle life. For instance, in applications where cost per Watt-Hour (Wh) is paramount, such as grid storage and traction applications, the use of an aqueous electrolyte in combination with inexpensive sulfur as the cathode active material can be a key enabler for the utility and automotive industries, for example, providing a cost effective and compact solution for load leveling, electric vehicles and renewable energy storage. Sulfur cathodes, and methods of fabricating lithium sulfur cells, in particular for loading lithium sulfide into the cathode structures, provide further advantages.

  7. Sulfur cycle

    Digital Repository Service at National Institute of Oceanography (India)

    LokaBharathi, P.A.

    Microbes, especially bacteria, play an important role in oxidative and reductive cycle of sulfur. The oxidative part of the cycle is mediated by photosynthetic bacteria in the presence of light energy and chemosynthetic forms in the absence of light...

  8. Sulfur Mustard

    Science.gov (United States)

    ... in of the vapors can cause chronic respiratory disease, repeated respiratory infections, or death. Extensive eye exposure can cause permanent blindness. Exposure to sulfur mustard may increase a person’s risk for lung and respiratory cancer. ...

  9. Purification of water polluted with oil and sulfurous closed-ring and aromatic compounds contained in oil and oil products using bacteria relating to thiosphaera

    International Nuclear Information System (INIS)

    Kurashov, V.M.; Sakhno, T.V.; Gavrilov, V.S.; Zijatdinov, R.N.

    2005-01-01

    The intensity of natural purification (self-purification) of reservoirs polluted with oil and oil products is determined by microorganisms. Hydrocarbon-oxidizing microorganisms are constant natural constituent of biocenose in reservoirs. However, as a result of outflows, the oil and oil products concentration exceeds maximum values allowing normal vital functions of microorganisms resulting in breaking micro-biocenose suppression of vital functions of bacteria. In this regard, elective anaerobic microorganisms of Thiosphaera are worthy of notice. We found out that bacteria belonging to Thiosphaera pantotropha decomposed oil at high oil concentrations in water (at oil concentration like 1 liter of oil in 1 liter of water). And this is when aerobic microorganisms lose their vital functions at maximum concentration of 20 g of oil in 1 liter of water. To intensify the process of oil decomposition we emulsified oil with aqueous solutions of salts. Thiosphaera pantotropha are found out to decompose oil in a wide range of ratio between oil and aqueous solutions of salts: from 1:10 to 10:1. The water solutions salinity made from 20 g/l to 80 g/l. It must be noticed that, since the Thiosphaera pantotropha are elective anaerobes and decompose oil both in presence and in absence of oxygen, it is not necessary anymore to conduct the process under strictly anaerobic conditions and to supply additional oxygen. This makes it possible to simplify the process of biodegradation of oil and to make this process practically more feasible and economically more profitable being compared to the processes based on the use of other species of bacteria. We found out that Thiosphaera decompose sulfurous closed-ring and aromatic compounds in oil which are chemically and thermally stable and can be hardly decomposed, and possess extremely poisonous properties, as well. The use of microorganisms of Thiosphaera pantotropha allows to purify waters polluted with oil and oil products both during

  10. Microbial pathways in colonic sulfur metabolism and links with health and disease

    Directory of Open Access Journals (Sweden)

    Franck eCarbonero

    2012-11-01

    Full Text Available Sulfur is both crucial to life and a potential threat to health. While colonic sulfur metabolism mediated by eukaryotic cells is relatively well studied, much less is known about sulfur metabolism within gastrointestinal microbes. Sulfated compounds in the colon are either of inorganic (e.g., sulfates, sulfites or organic (e.g., dietary amino acids and host mucins origin. The most extensively studied of the microbes involved in colonic sulfur metabolism are the sulfate-reducing bacteria, which are common colonic inhabitants. Many other microbial pathways are likely to shape colonic sulfur metabolism as well as the composition and availability of sulfated compounds, and these interactions need to be examined in more detail. Hydrogen sulfide is the sulfur derivative that has attracted the most attention in the context of colonic health, and the extent to which it is detrimental or beneficial remains in debate. Several lines of evidence point to sulfate-reducing bacteria or exogenous hydrogen sulfide as potential players in the etiology of intestinal disorders, inflammatory bowel diseases and colorectal cancer in particular. Generation of hydrogen sulfide via pathways other than dissimilatory sulfate reduction may be as, or more, important than those involving the sulfate-reducing bacteria. We suggest here that a novel axis of research is to assess the effects of hydrogen sulfide in shaping colonic microbiome structure. Clearly, in-depth characterization of the microbial pathways involved in colonic sulfur metabolism is necessary for a better understanding of its contribution to colonic disorders and development of therapeutic strategies.

  11. Identification of organic sulfur compounds in coal bitumen obtained by different extraction techniques using comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometric detection

    Energy Technology Data Exchange (ETDEWEB)

    Machado, Maria Elisabete; Cappelli Fontanive, Fernando; Bastos Caramao, Elina; Alcaraz Zini, Claudia [Universidade Federal do Rio Grande do Sul, Instituto de Quimica, Porto Alegre, RS (Brazil); Oliveira, Jose Vladimir de [URI, Universidade Regional Integrada do Alto Uruguai e das Missoes, Erechim, RS (Brazil)

    2011-11-15

    The determination of organic sulfur compounds (OSC) in coal is of great interest. Technically and operationally these compounds are not easily removed and promote corrosion of equipment. Environmentally, the burning of sulfur compounds leads to the emission of SO{sub x} gases, which are major contributors to acid rain. Health-wise, it is well known that these compounds have mutagenic and carcinogenic properties. Bitumen can be extracted from coal by different techniques, and use of gas chromatography coupled to mass spectrometric detection enables identification of compounds present in coal extracts. The OSC from three different bitumens were tentatively identified by use of three different extraction techniques: accelerated solvent extraction (ASE), ultrasonic extraction (UE), and supercritical-fluid extraction (SFE). Results obtained from one-dimensional gas chromatography (1D GC) coupled to quadrupole mass spectrometric detection (GC-qMS) and from two-dimensional gas chromatography with time-of-flight mass spectrometric detection (GC x GC-TOFMS) were compared. By use of 2D GC, a greater number of OSC were found in ASE bitumen than in SFE and UE bitumens. No OSC were identified with 1D GC-qMS, although some benzothiophenes and dibenzothiophenes were detected by use of EIM and SIM modes. GC x GC-TOFMS applied to investigation of OSC in bitumens resulted in analytical improvement, as more OSC classes and compounds were identified (thiols, sulfides, thiophenes, naphthothiophenes, benzothiophenes, and benzonaphthothiophenes). The roof-tile effect was observed for OSC and PAH in all bitumens. Several co-elutions among analytes and with matrix interferents were solved by use of GC x GC. (orig.)

  12. Sulfur, selenium, tellurium and polonium

    International Nuclear Information System (INIS)

    Berry, F.J.

    1987-01-01

    This chapter on the coordination compounds of sulfur, selenium, tellurium and polonium starts with an introduction to the bonding, valence and geometry of the elements. Complexes of the group VIB elements are discussed with particular reference to the halo and pseudohalide complexes, oxo acid complexes, oxygen and nitrogen donor complexes and sulfur and selenium donor complexes. There is a section on the biological properties of the complexes discussed. (UK)

  13. Sulfur problems in Swedish agriculture

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, O

    1959-01-01

    The present paper deals with some aspects of the sulfur situation in Swedish agriculture with special emphasis on the importance of and relationships among various sources of sulfur supply. An inventory of the sulfur content of Swedish soils and hay crops includes 649 soil samples and a corresponding number of hay samples from 59 locations. In a special investigation the samples were found to be representative of normal Swedish farm land. It is concluded that the amount of sulfur compounds in the air is the primary factor which determines the amount of sulfur added to the soil from the atmosphere. Compared with values obtained in other countries, the amount of sulfur added by the precipitation in Sweden is very low. The distribution in air and precipitation of sulfur from an industrial source was studied in a special investigation. An initial reason for the present study was the damage to vegetation caused by smoke from an industrial source. It was concluded that the average conditions in the vicinity of the industrial source with respect to smoke constituents in the air and precipitation were unfavorable only to the plants directly within a very narrow region. Relationships among the sulfur contents of air, of precipitation, of soils and of plants have been subject to special investigations. In the final general discussion and conclusions it is pointed out that the results from these investigations indicate evident differences in the sulfur status of Swedish soils. The present trend toward the use of more highly concentrated fertilizers poor in sulfur may be expected to cause a considerable change in the sulfur situation in Swedish agriculture. 167 references, 40 figures, 44 tables.

  14. Application of a macrocyclic compound, bambus[6]uril, in tailor-made liquid membranes for highly selective electromembrane extractions of inorganic anions

    Czech Academy of Sciences Publication Activity Database

    Šlampová, Andrea; Šindelář, V.; Kubáň, Pavel

    2017-01-01

    Roč. 950, JAN (2017), s. 49-56 ISSN 0003-2670 R&D Projects: GA ČR(CZ) GA16-09135S Institutional support: RVO:68081715 Keywords : bambus[6]uril * electromembrane extraction selectivity * inorganic anions Subject RIV: CB - Analytical Chemistry, Separation OBOR OECD: Analytical chemistry Impact factor: 4.950, year: 2016

  15. Inorganic Fullerene-Like Nanoparticles and Inorganic Nanotubes

    Directory of Open Access Journals (Sweden)

    Reshef Tenne

    2014-11-01

    Full Text Available Fullerene-like nanoparticles (inorganic fullerenes; IF and nanotubes of inorganic layered compounds (inorganic nanotubes; INT combine low dimensionality and nanosize, enhancing the performance of corresponding bulk counterparts in their already known applications, as well as opening new fields of their own [1]. This issue gathers articles from the diverse area of materials science and is devoted to fullerene-like nanoparticles and nanotubes of layered sulfides and boron nitride and collects the most current results obtained at the interface between fundamental research and engineering.[...

  16. Ambient Pressure Hydrodesulfurization of Refractory Sulfur Compounds in Highly Sensitive μ-Reactor Platform Coupled to a Time-of-Flight Mass Spectrometer

    DEFF Research Database (Denmark)

    Christoffersen, Ann-Louise N.; Bodin, Anders; Elkjær, Christian F.

    2018-01-01

    the refractory sulfur from different petroleum streams mostly found in the form of the alkyl-substituted dibenzothiophenes (β-DBTs). In this work we demonstrate how a setup dedicated to testing minute amounts (nanogram) of well-defined catalytic systems in μ-reactors can be used in the gas-phase HDS of the model...

  17. Preparation and characterization of a layered perovskite-type organic-inorganic hybrid compound (C8NH6-CH2CH2NH3)2CuCl4

    International Nuclear Information System (INIS)

    Zheng Yingying; Wu Gang; Deng Meng; Chen Hongzheng; Wang Mang; Tang, B.-Z.

    2006-01-01

    The organic-inorganic hybrid compound (C 8 NH 6 -CH 2 CH 2 NH 3 ) 2 CuCl 4 (AEI-CuCl 4 ) was synthesized from ethanol solution containing copper chloride and 3-2-(aminoethyl) indole hydrochloride (AEI-HCl). High order diffraction peaks corresponding to (0 0 l; l = 2, 4, 6, ...) observed in the X-ray diffraction profile of AEI-CuCl 4 indicated the formation of hybrid crystal with layered perovskite structure. The organic-inorganic hybrid crystal thin film can be easily prepared by spin-coating method from the ethanol solution of the AEI-CuCl 4 perovskite and it showed characteristic absorptions of CuCl-based layered perovskite centered at 288 and 388 nm, as well as the photoluminescence peak at around 420 nm. The unaided-eye-detectable blue fluorescence emission comes from the cooperation of AEI-HCl and AEI-CuCl 4 perovskite, in which protonized aminoethyl indole dominates the shape of the spectrum and the enhancement of emission intensity is due to the formation of the perovskite structure. The thermal analysis presented that the AEI-CuCl 4 perovskite started to melt at 182 deg. C, together with the beginning of the decomposition of the hybrids. Compared with the organic-inorganic perovskite hybrids reported previously, the AEI-CuCl 4 perovskite shows a novel stepwise decomposition behavior

  18. Sulfur Earth

    Science.gov (United States)

    de Jong, B. H.

    2007-12-01

    Variations in surface tension affect the buoyancy of objects floating in a liquid. Thus an object floating in water will sink deeper in the presence of dishwater fluid. This is a very minor but measurable effect. It causes for instance ducks to drown in aqueous solutions with added surfactant. The surface tension of liquid iron is very strongly affected by the presence of sulfur which acts as a surfactant in this system varying between 1.9 and 0.4 N/m at 10 mass percent Sulfur (Lee & Morita (2002), This last value is inferred to be the maximum value for Sulfur inferred to be present in the liquid outer core. Venting of Sulfur from the liquid core manifests itself on the Earth surface by the 105 to 106 ton of sulfur vented into the atmosphere annually (Wedepohl, 1984). Inspection of surface Sulfur emission indicates that venting is non-homogeneously distributed over the Earth's surface. The implication of such large variation in surface tension in the liquid outer core are that at locally low Sulfur concentration, the liquid outer core does not wet the predominantly MgSiO3 matrix with which it is in contact. However at a local high in Sulfur, the liquid outer core wets this matrix which in the fluid state has a surface tension of 0.4 N/m (Bansal & Doremus, 1986), couples with it, and causes it to sink. This differential and diapiric movement is transmitted through the essentially brittle mantle (1024 Pa.s, Lambeck & Johnson, 1998; the maximum value for ice being about 1030 Pa.s at 0 K, in all likely hood representing an upper bound of viscosity for all materials) and manifests itself on the surface by the roughly 20 km differentiation, about 0.1 % of the total mantle thickness, between topographical heights and lows with concomitant lateral movement in the crust and upper mantle resulting in thin skin tectonics. The brittle nature of the medium though which this movement is transmitted suggests that the extremes in topography of the D" layer are similar in range to

  19. Optimization of on-line hydrogen stable isotope ratio measurements of halogen- and sulfur-bearing organic compounds using elemental analyzer-chromium/high-temperature conversion isotope ratio mass spectrometry (EA-Cr/HTC-IRMS).

    Science.gov (United States)

    Gehre, Matthias; Renpenning, Julian; Geilmann, Heike; Qi, Haiping; Coplen, Tyler B; Kümmel, Steffen; Ivdra, Natalija; Brand, Willi A; Schimmelmann, Arndt

    2017-03-30

    Accurate hydrogen isotopic analysis of halogen- and sulfur-bearing organics has not been possible with traditional high-temperature conversion (HTC) because the formation of hydrogen-bearing reaction products other than molecular hydrogen (H 2 ) is responsible for non-quantitative H 2 yields and possible hydrogen isotopic fractionation. Our previously introduced, new chromium-based EA-Cr/HTC-IRMS (Elemental Analyzer-Chromium/High-Temperature Conversion Isotope Ratio Mass Spectrometry) technique focused primarily on nitrogen-bearing compounds. Several technical and analytical issues concerning halogen- and sulfur-bearing samples, however, remained unresolved and required further refinement of the reactor systems. The EA-Cr/HTC reactor was substantially modified for the conversion of halogen- and sulfur-bearing samples. The performance of the novel conversion setup for solid and liquid samples was monitored and optimized using a simultaneously operating dual-detection system of IRMS and ion trap MS. The method with several variants in the reactor, including the addition of manganese metal chips, was evaluated in three laboratories using EA-Cr/HTC-IRMS (on-line method) and compared with traditional uranium-reduction-based conversion combined with manual dual-inlet IRMS analysis (off-line method) in one laboratory. The modified EA-Cr/HTC reactor setup showed an overall H 2 -recovery of more than 96% for all halogen- and sulfur-bearing organic compounds. All results were successfully normalized via two-point calibration with VSMOW-SLAP reference waters. Precise and accurate hydrogen isotopic analysis was achieved for a variety of organics containing F-, Cl-, Br-, I-, and S-bearing heteroelements. The robust nature of the on-line EA-Cr/HTC technique was demonstrated by a series of 196 consecutive measurements with a single reactor filling. The optimized EA-Cr/HTC reactor design can be implemented in existing analytical equipment using commercially available material and

  20. Human Exposure and Health Effects of Inorganic and Elemental Mercury

    OpenAIRE

    Park, Jung-Duck; Zheng, Wei

    2012-01-01

    Mercury is a toxic and non-essential metal in the human body. Mercury is ubiquitously distributed in the environment, present in natural products, and exists extensively in items encountered in daily life. There are three forms of mercury, i.e., elemental (or metallic) mercury, inorganic mercury compounds, and organic mercury compounds. This review examines the toxicity of elemental mercury and inorganic mercury compounds. Inorganic mercury compounds are water soluble with a bioavailability o...

  1. Synthesis, structural characterization, thermal analysis, and DFT calculation of a novel zinc (II)-trifluoro-β-diketonate 3D supramolecular nano organic-inorganic compound with 1,3,5-triazine derivative

    Energy Technology Data Exchange (ETDEWEB)

    Mirtamizdoust, Babak, E-mail: babakm.tamizdoust@gmail.com [Department of Chemistry, Yasouj University, Yasouj, 75918-74831 (Iran, Islamic Republic of); Department of Chemistry, Faculty of Science, University of Qom, PO Box 37185-359, Qom, Islamic Republic of Iran (Iran, Islamic Republic of); Ghaedi, Mehrorang [Department of Chemistry, Yasouj University, Yasouj, 75918-74831 (Iran, Islamic Republic of); Hanifehpour, Younes, E-mail: y_hanifehpour@yu.ac.kr [School of Mechanical Engineering, WCU Nano Research Center, Yeungnam University, Gyongsan, 712-749 (Korea, Republic of); Mague, Joel T. [Department of Chemistry, Tulane University, New Orleans (United States); Joo, Sang Woo, E-mail: swjoo1@gmail.com [School of Mechanical Engineering, WCU Nano Research Center, Yeungnam University, Gyongsan, 712-749 (Korea, Republic of)

    2016-10-01

    A sonochemical method was used to synthesize a novel nano-structure of a zinc(II) organic-inorganic compound [Zn(dapt){sub 2}(ttfa){sub 2}] (1) [dapt = 2,4-diamino-6-phenyl-1,3,5-triazine and ttfa = 2-thenoyltrifluoroacetonate]. The new nanostructure was characterized by scanning electron microscopy, X-ray powder diffraction, elemental analysis, and thermal analysis. The single-crystal X-ray structure shows that 1 is a discrete coordination compound. Strong intra- and intermolecular hydrogen bonds are observed in the structure with the latter forming chains of molecules running parallel to (110). The chains are further extended into a three-dimensional supramolecular structure by intermolecular C−F⋯π interactions between trifluoromethyl and triazine moieties. The coordination number of the zinc(II) ion is six (ZnN{sub 2}O{sub 4}), and the coordination sphere is tetragonally elongated octahedral. The structure of the title complex was optimized by DFT calculations. - Highlights: • A new zinc(II) 3D coordination supramolecular compound was synthesized. • Ultrasound synthesis of nano coordination compound have been reported. • The X-ray crystal structure of the compound is reported.

  2. Evaluation of Toxicological Effects of an Aqueous Extract of Shells from the Pecan Nut Carya illinoinensis (Wangenh. K. Koch and the Possible Association with Its Inorganic Constituents and Major Phenolic Compounds

    Directory of Open Access Journals (Sweden)

    Luiz Carlos S. Porto

    2016-01-01

    Full Text Available Background. Industrial processing of the pecan nut Carya illinoinensis K. Koch generated a large amount of shells, which have been used to prepare nutritional supplements and medicinal products; however, the safe use of shells requires assessment. This study evaluated the toxic, genotoxic, and mutagenic effects of pecan shell aqueous extract (PSAE and the possible contribution of phenolic compounds, ellagic and gallic acids, and inorganic elements present in PSAE to induce toxicity. Results. Levels of inorganic elements like K, P, Cl, and Rb quantified using the Particle-Induced X-Ray Emission method were higher in PSAE than in pecan shells, while Mg and Mn levels were higher in shells. Mice showed neurobehavioral toxicity when given high PSAE doses (200–2,000 mg kg−1. The LD50 was 1,166.3 mg kg−1. However, PSAE (50–200 mg·kg−1 and the phenolic compounds (10–100 mg·kg−1 did not induce DNA damage or mutagenicity evaluated using the comet assay and micronucleus test. Treatment with ellagic acid (10–100 mg·kg−1 decreased triglyceride and glucose levels, while treatments with PSAE and gallic acid had no effect. Conclusion. Pecan shell toxicity might be associated with high concentrations of inorganic elements such as Mn, Al, Cu, and Fe acting on the central nervous system, besides phytochemical components, suggesting that the definition of the safe dose should take into account the consumption of micronutrients.

  3. Review: Circulation of Inorganic Elements in Combustion of Alternative Fuels in Cement Plants

    DEFF Research Database (Denmark)

    Cortada Mut, Maria del Mar; Nørskov, Linda Kaare; Jappe Frandsen, Flemming

    2015-01-01

    Cement production is an energy-intensive process, which traditionally has been dependent on fossil fuels. However, the use of alternative fuels, i.e., selected waste, biomass, and byproducts with recoverable calorific value, is constantly increasing. Combustion of these fuels is more challenging...... the internal circulation of S, Cl, Na, and K. Compounds containing these elements, such as alkali salts, evaporate when exposed to high temperatures and subsequently condense in colder parts of the plant. The transformation of the volatile inorganic species at different locations in the cement plant...... cycles of inorganic elements that are established within the cement plant and their dependence on process parameters. Special focus is given to the sulfur cycle. This cycle is intensified by CaSO4 decomposition, making it sensitive to local reducing conditions....

  4. Halophilic and haloalkaliphilic sulfur-oxidizing bacteria

    NARCIS (Netherlands)

    Sorokin, D.Y.; Banciu, H.; Robertson, L.A.; Kuenen, J.G.; Muntyan, M.S.; Muyzer, G.; Rosenberg, E.; DeLong, F.; Delong, E.; Lory, S.; Stackebrandt, E.; Thompson, F.

    2013-01-01

    Chemotrophic sulfur-oxidizing bacteria (SOB) represent an important functional group of microorganisms responsible for the dark oxidation of reduced sulfur compounds generated by sulfidogens. Until recently, only a single genus of halophilic SOB (Halothiobacillus) has been described, and nothing was

  5. Inorganic chemistry of earliest sediments

    International Nuclear Information System (INIS)

    Ochiai, E.I.

    1983-01-01

    A number of inorganic elements are now known to be essential to organisms. Chemical evolutionary processes involving carbon, hydrogen, nitrogen and oxygen have been studied intensively and extensively, but the other essential elements have been rather neglected in the studies of chemical and biological evolution. This article attempts to assess the significance of inorganic chemistry in chemical and biological evolutionary processes on the earth. Emphasis is placed on the catalytic effects of inorganic elements and compounds, and also on possible studies on the earliest sediments, especially banded iron formation and stratabound copper from the inorganic point of view in the hope of shedding some light on the evolution of the environment and the biological effects on it. (orig./WL)

  6. Investigation on the self-association of an inorganic coordination compound with biological activity (Casiope?na III-ia) in aqueous solution

    OpenAIRE

    Mar?n-Medina, Alejandro; Garc?a-Ramos, Juan Carlos; Ru?z-Azuara, Lena; Carrillo-Nava, Ernesto

    2016-01-01

    From studies using different experimental techniques employed to determine the presence of aggregates e.g. isothermal titration calorimetry, surface tension, electrical conductivity, UV?Vis spectrophotometry, dynamic and static light scattering, it is clearly demonstrated that the compound [Cu(4, 4?-dimethyl-2, 2?-bipyridine)(acetylacetonato)H2O]NO3 (Casiope?na III-ia), promising member of a family of new generation compounds for cancer treatment, is able to auto associate in aqueous media. P...

  7. Inorganic chemistry and medicine

    International Nuclear Information System (INIS)

    Sadler, P.J.; Guo, Z.

    1999-01-01

    Inorganic chemistry is beginning to have a major impact on medicine. Not only does it offer the prospect of the discovery of truly novel drugs and diagnostic agents, but it promises to make a major contribution to our understanding of the mechanism of action of organic drugs too. Most of this article is concerned with recent developments in medicinal coordination chemistry. The role of metal organic compounds of platinum, titanium, ruthenium, gallium, bismuth, gold, gadolinium, technetium, silver, cobalt in the treatment or diagnosis of common diseases are briefly are examined

  8. In vitro assessment of the growth and plasma membrane H+ -ATPase inhibitory activity of ebselen and structurally related selenium- and sulfur-containing compounds in Candida albicans.

    Science.gov (United States)

    Orie, Natalie N; Warren, Andrew R; Basaric, Jovana; Lau-Cam, Cesar; Piętka-Ottlik, Magdalena; Młochowski, Jacek; Billack, Blase

    2017-06-01

    Ebselen (EB, compound 1) is an investigational organoselenium compound that reduces fungal growth, in part, through inhibition of the fungal plasma membrane H + -ATPase (Pma1p). In the present study, the growth inhibitory activity of EB and of five structural analogs was assessed in a fluconazole (FLU)-resistant strain of Candida albicans (S2). While none of the compounds were more effective than EB at inhibiting fungal growth (IC 50  ∼ 18 μM), two compounds, compounds 5 and 6, were similar in potency. Medium acidification assays performed with S2 yeast cells revealed that compounds 4 and 6, but not compounds 2, 3, or 5, exerted an inhibitory activity comparable to EB (IC 50  ∼ 14 μM). Using a partially purified Pma1p preparation obtained from S2 yeast cells, EB and all the analogs demonstrated a similar inhibitory activity. Taken together, these results indicate that EB analogs are worth exploring further for use as growth inhibitors of FLU-resistant fungi. © 2017 Wiley Periodicals, Inc.

  9. Quantification of Sulfur by the Wet Oxidation for the Determination of 35S

    International Nuclear Information System (INIS)

    Lee, Heung N.; Kang, Sang Hoon; Ahn, Hong Joo; Han, Sun Ho; Jee, Kwang Yong

    2006-01-01

    Natural sulfur contains four stable isotopes. The main isotopes are 32 S (95.02%) and 34 S (4.21%). Beside the stable isotopes, there exist also a radioactive one 35 S (T 1/2 = 87.4 d, Emax = 167 keV, pure β - emitter). Sulfur- 35 is one of the cosmogenic radionuclides generated by cosmic rays through spallation of argon atoms. 35 S for the labeled compound such as 35 S-thiourea is produced from the pile irradiation of the neutron ( 35 Cl(n,p) 35 S). Most 35 S produced by cosmic rays is rapidly converted to sulfur dioxide (SO 2 ) and sulfate (SO 4 2- ), and attached on the ambient aerosols. The quantities of 35 S do not present a significant external exposure hazard since the low-energy emissions barely penetrate the outer dead layer of skin. For uptakes of inorganic sulfur, 15% is assumed to be retained with a 20 day biological half-life and 5% retained with a 2,000 day biological half-life. The remaining 80% is assumed to be rapidly excreted. Because of its relatively weak emission, 35 S is primarily an internal radiation hazard. TLDs are not effective and Geiger-Muller detectors can measure to low efficiency (∼10%) for detecting 35 S. Therefore, it is important to use careful handling and frequent monitoring, either with survey meters with thin- windows probes or by taking wipe samples and counting in a liquid scintillation counter (LSC)

  10. Early steroid sulfurization in surface sediments of a permanently stratified lake (Ace Lake, Antarctica)

    Science.gov (United States)

    Kok, Marika D.; Rijpstra, W. Irene C.; Robertson, Lisette; Volkman, John K.; Sinninghe Damstéé, Jaap S.

    2000-04-01

    Surface sediments (0-25 cm) from Ace Lake (eastern Antarctica), a saline euxinic lake, were analyzed to study the early incorporation of reduced inorganic sulfur species into organic matter. The apolar fractions were shown to consist predominantly of dimeric (poly)sulfide linked C 27-C 29 steroids. These steroid moieties were identified by GC-MS analysis of the apolar fractions after cleavage of polysulfide linkages using MeLi and MeI and after desulfurisation. The polar fractions contained the oligomeric analogues. The S-bound steroids are most likely formed by sulfur incorporation into steroidal ketones formed from Δ 5 sterols by biohydrogenation by anaerobic bacteria. The concentrations of these sulfurised steroids increased with depth in the sediment. The sulfurisation reaction is completed in 1000-3000 years. Despite a wide range of functionalised lipids present in these sediments that are potentially available for sulfurisation, there is a very strong preference for the incorporation of sulfur into steroidal compounds. A predominance of sulfurised C 27 steroids contrasted with the distribution of free sterols, which showed a strong predominance of C 29 sterols. This indicates that the incorporation of sulfur is biased towards C 27 sterols. The results demonstrate that intermolecular sulfurisation of organic matter can occur in surface sediments at low temperatures and in the absence of light.

  11. Concentrations of inorganic elements in biomass fuels and recovery in the different ash fractions

    NARCIS (Netherlands)

    Obernberger, I.; Biedermann, F.; Widmann, W.; Riedl, R.

    1997-01-01

    Inorganic elements and compounds in biomass fuels influence the combustion process and the composition of the ashes produced. Consequently, knowledge about the material fluxes of inorganic elements and compounds during biomass combustion for different kinds of biofuels and their influencing

  12. Gamma radiolysis of aliphatic sulfur compounds in aqueous solutions. A study to contribute to the analysis of the end products of the OH radical-induced oxidation of aliphatic mercaptanes, sulfides, and disulfides

    International Nuclear Information System (INIS)

    Weiss, J.

    1982-01-01

    By identifying and determining numerous hitherto unknown end products, the study in hand contributes to a better insight into the radiation chemical processes occurring in OH radical-induced oxidation of aliphatic sulfur compounds. An extraction method has been developed for the qualitative and quantitative analysis of end products in aqueous solution in order to determine these compounds down to the level of trace amounts. Separation of endproducts is achieved by means of gas chromatography and high-pressure liquid chromatography, subsequent identification by GC-MS analysis. Aliphatic mercaptanes are oxidized by OH radicals to thiyl radicals which after combination can be detected as disulfide. At high radiation doses, secondary reactions will lead to polysulfides of which the homologues could first be prepared as the pure substance. The end products of the γ-radiolysis of aliphatic thioethers are determined to be dithia compounds, symmetrical or asymmetrical disulfides, or polysulfides, depending on the thioethers. With some end products, the radiation chemical yield is found to be a function of the absorbed dose so that material balances are impossible. Intermediate thiyl, α-alkyl mercaptoalkyl or alkyl radicals can be captured by tetramethyl ethylene, cyclohexene or p-benzoquinone, and can then be identified as the relevant adducts. (orig./RB) [de

  13. Room-temperature ductile inorganic semiconductor

    Science.gov (United States)

    Shi, Xun; Chen, Hongyi; Hao, Feng; Liu, Ruiheng; Wang, Tuo; Qiu, Pengfei; Burkhardt, Ulrich; Grin, Yuri; Chen, Lidong

    2018-05-01

    Ductility is common in metals and metal-based alloys, but is rarely observed in inorganic semiconductors and ceramic insulators. In particular, room-temperature ductile inorganic semiconductors were not known until now. Here, we report an inorganic α-Ag2S semiconductor that exhibits extraordinary metal-like ductility with high plastic deformation strains at room temperature. Analysis of the chemical bonding reveals systems of planes with relatively weak atomic interactions in the crystal structure. In combination with irregularly distributed silver-silver and sulfur-silver bonds due to the silver diffusion, they suppress the cleavage of the material, and thus result in unprecedented ductility. This work opens up the possibility of searching for ductile inorganic semiconductors/ceramics for flexible electronic devices.

  14. EELS data acquisition, processing and display for the Zeiss CEM 902 based on LOTUS 1-2-3: application examples from a biological system and inorganic transition metal compounds.

    Science.gov (United States)

    Drechsler, M; Cantow, H J

    1991-04-01

    A personal computer combined with LOTUS 1-2-3 software, including the RS232 module of LOTUS MEASURE and a 12-bit ADC, has been used for data acquisition of electron energy-loss spectroscopy (EELS) spectra with the Zeiss CEM 902. The internal macro language of LOTUS 1-2-3 allows a menu-driven procedure. Macro-programs partly combined with external FORTRAN programs can be chosen from the menu for background subtraction, removal of multiple scattering effects by deconvolution, elemental quantification and several utilities. For special applications or conditions the macro programs can easily be modified. Spectra from crystals of two inorganic transition metal compounds, ruthenium trichloride and vanadium disulphide, and from a biological sample are presented as examples of the application of this software.

  15. Dew point of gases with low sulfuric acid content

    Energy Technology Data Exchange (ETDEWEB)

    Fieg, J.

    1981-07-01

    Discusses control of air pollution caused by sulfur compounds in solid fuels during combustion. Excessive amount of oxygen during combustion leads to formation of sulfur trioxide. Sulfur trioxide reacts with water vapor and forms sulfuric acid. Chemical reactions which lead to formation of sulfuric acid are described. Conditions for sulfuric acid condensation are analyzed. Several methods for determining dew point of flue gases with low sulfuric acid content are reviewed: methods based on determination of electric conductivity of condensed sulfuric acid (Francis, Cheney, Kiyoure), method based on determination of sulfuric acid concentration in the gaseous phase and in the liquid phase after cooling (Lee, Lisle and Sensenbaugh, Ross and Goksoyr). (26 refs.) (In Polish)

  16. The synthesis, characterization and optical properties of Si4+ and Pr4+ doped Y6 MoO12 compounds: environmentally benign inorganic pigments with high NIR reflectance

    International Nuclear Information System (INIS)

    George, Giable; Reddy, M.L.P.

    2010-01-01

    Full text: Much interest has attended roofing materials with high solar reflectance and high thermal emittance, so that interiors stay cool, thereby reducing the demand for air conditioned buildings. The heat producing region of the infrared radiations ranges from 700-1100 nm. Replacing conventional pigments with 'cool pigments' that absorb less NIR radiation can provide coatings similar in color to that of conventional roofing materials, but with higher solar reflectance. NIR reflective pigments have been used in the military, construction, plastics and ink industries. Complex inorganic pigments based on mixed metal oxides (eg., chromium green, cobalt blue, cadmium stannate, lead chromate, cadmium yellow and chrome titanate yellow), which have been used in camouflage, absorb visible light but reflect the NIR portion of incident radiation. However, many of these pigments are toxic and there is a need to develop novel colored, NIR-reflecting inorganic pigments that are less hazardous to the environment. In this work, a series of NIR reflective colored pigments of formula Y 6-x M x MoO 12+δ (where M Si 4+ or Pr 4+ and x ranges from 0 to 1.0) were synthesized by traditional solid-state route and applied to asbestos cement roofing material so as to evaluate their use as 'cool pigments'. The phase purity of the calcined pigment samples were determined using powder X-ray diffraction. The diffuse reflectance of the powdered pigment samples were measured using a UV-Vis-NIR Spectrometer. The Lab color coordinates were evaluated by CIE 1976 color scale. Replacing Si 4+ for Y 3+ in Y 6 MoO 12 changed the color from light-yellow to dark-yellow and the band gap decreased from 2.60 to 2.45 eV due to O 2p -Mo 4d charge transfer transitions. In contrast, replacing Pr 4+ for Y 3+ changed the color from light yellow to dark brown and the band gap shifted from 2.60 to 1.90 eV. The coloring mechanism is based on the introduction of an additional 4f 1 electron energy level of Pr 4

  17. Effects of organic and inorganic compounds of diesel exhaust particles on the mucociliary epithelium: An experimental study on the frog palate preparation.

    Science.gov (United States)

    Trindade, Sergio Henrique Kiemle; Seriani, Robson; Lorenzi-Filho, Geraldo; de Mello Júnior, João Ferreira; Sennes, Luiz Ubirajara; Saldiva, Paulo Hilário Nascimento; Macchione, Mariângela

    2018-02-01

    The toxic actions of acute exposition to different diesel exhaust particles (DEPA) fractions on the mucociliary epithelium are not yet fully understood due to different concentrations of organic and inorganic elements. These chemicals elements produce damage to the respiratory epithelium and exacerbate pre-existent diseases. In our study we showed these differences in two experimental studies. Study I (dose-response curve - DRCS): Forty frog-palates were exposed to the following dilutions: frog ringer, intact DEPA diluted in frog-ringer at 3mg/L, 6mg/L and 12mg/L. Study II (DEPF) (DEPA fractions diluted at 12mg/L): Fifty palates - Frog ringer, intact DEPA, DEPA treated with hexane, nitric acid and methanol. Variables analyzed: relative time of mucociliary transport (MCT), ciliary beating frequency (CBF) and morphometric analysis for mucin profile (neutral/acid) and vacuolization. The Results of DRCS: Group DEPA-12mg/L presented a significant increase in the MCT (pepithelium, by promoting a significant increase in the MCT associated to changes in the chemical profile of the intracellular mucins. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Determination of inorganic compounds in drinking water on the basis of house water heater scale, part 1: Determination of heavy metals and uranium

    Directory of Open Access Journals (Sweden)

    Rajković Miloš B.

    2004-01-01

    Full Text Available The analysis of scale originated from drinking water on the house water heater, showed that scale is basically calcium carbonate that crystallizes hexagonally in the form of calcite. Scale taken as a sample from different spots in Belgrade – upper town of Zemun (sample 1 and Pančevo (sample 2 showed different configuration although it came from the same waterworks. That indicates either that the water flowing through waterworks pipes in different parts of the city is not the same or the waterworks net is not the same (age, maintaining, etc. All the elements which are dominant in drinking water (Ca, Mg, K, and Na, and which could be found in water by natural processes, are by their content far below the values regulated by law. The analysis also showed the presence of many metals: Ti, Pb, Zn, Cu Li, Sr, Cd, and Cr in the first sample, which are not found in the scale taken near Pančevo. The results obtained by calculating the mass concentration in drinking water on the basis of scale content, showed that both waters belonged to the category of low mineral waters. Contents of inorganic substances in these waters (117.85 mg/dm3 for sample 1 or 80.83 mg/dm3 for sample 2 are twice lower than the values predicted by the legislation. Gammaspectrometric analysis indicates the presence of radioactive elements – uranium and strontium which can influence human health.

  19. Welcome to Inorganics: A New Open Access, Inclusive Forum for Inorganic Chemistry

    Directory of Open Access Journals (Sweden)

    Duncan H. Gregory

    2013-06-01

    Full Text Available One of the beauties of inorganic chemistry is its sheer diversity. Just as chemistry sits at the centre of the sciences, inorganic chemistry sits at the centre of chemistry itself. Inorganic chemists are fortunate in having the entire periodic table at their disposal, providing a palette for the creation of a multitude of rich and diverse compounds and materials from the simplest salts to the most complex of molecular species. It follows that the language of inorganic chemistry can thus be a demanding one, accommodating sub-disciplines with very different perspectives and frames of reference. One could argue that it is the unequivocal breadth of inorganic chemistry that empowers inorganic chemists to work at the interfaces, not just between the traditional Inorganic-Organic-Physical boundaries of the discipline, but in the regions where chemistry borders the other physical and life sciences, engineering and socio-economics. [...

  20. Structure, solution chemistry, antiproliferative actions and protein binding properties of non-conventional platinum(ii) compounds with sulfur and phosphorus donors

    NARCIS (Netherlands)

    Mügge, C.; Rothenburger, C.; Beyer, A.; Görls, H.; Gabbiani, C.; Casini, A.; Michelucci, E.; Landini, I.; Nobili, S.; Mini, E.; Messori, L.; Weigand, W.

    2011-01-01

    Twelve Pt(ii) complexes with cis-PtP2S2 pharmacophores (where P2 refers to two monodentate or one bidentate phosphane ligand and S2 is a dithiolato ligand) were prepared, characterized and evaluated as potential antiproliferative agents. The various compounds were first studied from the structural

  1. Inorganic chemistry

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    Two compounds (O 2 SbF 6 and IF 6 SbF 6 ) were tested as chemical reagents for trapping the heavier noble gases (isotopes of radon and xenon) released to the atmosphere by nuclear power plants and fuel reprocessing plants. Results on the Raman scattering of anhydrous liquid HF are reported. (U.S.)

  2. Different effects of inorganic and dimethylated arsenic compounds on cell morphology, cytoskeletal organization, and DNA synthesis in cultured Chinese hamster V79 cells

    Energy Technology Data Exchange (ETDEWEB)

    Ochi, Takafumi; Nakajima, Fumie [Department of Environmental Toxicology, Faculty of Pharmaceutical Sciences, Teikyo University, Sagamiko, Kanagawa (Japan); Fukumori, Nobutaka [Department of Toxicology, Tokyo Metropolitan Research Laboratory of Public Health, Hyakuninchou, Shinjyuku (Japan)

    1998-09-01

    Changes in cytoskeletal organization of cultured V79 cells exposed to arsenite and dimethylarsinic acid (DMAA), a methylated derivative of inorganic arsenics, and related changes, such as mitotic arrest and induction of multinucleated cells, were investigated in comparison with their effects on DNA synthesis. DMAA caused mitotic arrest and induction of multinucleated cells with a delay of 12 h relative to the mitotic arrest. By contrast, arsenite at equitoxic concentrations to DMAA was less effective than DMAA in causing mitotic arrest and in inducing multinucleated cells. Post-mitotic incubation of cells arrested in metaphase by 6 h incubation with 10 mM DMAA showed that the incidence of multinucleated cells increased conversely with a rapid decrease in metaphase cells. This suggests that metaphase-arrested cells can escape from metaphase, resulting in the appearance of multinucleated cells. The mitotic arrest caused by DMAA was accompanied by disruption of the microtubule network. By contrast, both arsenite and DMAA did not cause disorganization of actin stress fibers even when incubated at concentrations that caused a marked retardation of cell growth. Cells exposed to arsenite for 6 h showed marked inhibition of DNA synthesis, whereas inhibition by DMAA was not observed. When incubation was prolonged by 18 h, the arsenite-induced inhibition of DNA synthesis was mitigated. By contrast, inhibition of DNA synthesis by DMAA occurred in parallel with an increase in the population of mitotic cells. These results suggest that DMAA caused growth retardation and morphological changes via disruption of the microtubule network, and that arsenite-induced retardation of cell growth and inhibition of DNA synthesis were not attributable to the cytoskeletal changes. (orig.) (orig.) With 7 figs., 31 refs.

  3. Damage caused to vegetation by sulfurous and sulfuric acids in the atmosphere

    Energy Technology Data Exchange (ETDEWEB)

    Tatlock, R R; Thomson, R T

    1914-05-01

    This report, written in 1914, documents injuries to trees and shrubs in the United Kingdom which are attributed to sulfur compounds in air pollutions. Sampling, analytical and experimental procedures are discussed.

  4. Innovative method of direct determination of the content of paraffins, naphthenes, aromatics and sulfur compounds by capillary high-resolution gas chromatography

    Directory of Open Access Journals (Sweden)

    R. Baizhumanova

    2012-03-01

    Full Text Available Based on determination of individual Hydrocarbon (paraffins, naphthenes, aromatics and Sulphur components of fuels and their mixture on the thin bonded of absorber (the stationary phase is a 100-metre silica capillary column, containing 0.5μm film thickness of bonded dimethylpolysiloxane phase by means of the selective solvents (mobile phase combined with technique of ionization of separated compounds by Flame Ionization Detector (FID and Sulphur Chemiluminescence Detector (SCD.

  5. The coordination of sulfur in synthetic and biogenic Mg calcites: The red coral case

    Science.gov (United States)

    Perrin, J.; Rivard, C.; Vielzeuf, D.; Laporte, D.; Fonquernie, C.; Ricolleau, A.; Cotte, M.; Floquet, N.

    2017-01-01

    Sulfur has been recognized in biogenic calcites for a long time. However, its structural position is matter of debate. For some authors, sulfur is a marker of the organic matrix while it is part of the calcite structure itself for others. To better understand the place of sulfur in calcite, sulfated magnesian calcites (S-MgCalcite) have been synthetized at high pressure and temperature and studied by μ-XANES spectroscopy. S-MgCalcite XANES spectra show two different types of sulfur: sulfate (SO42-) as a predominant species and a small contribution of sulfite (SO32-), both substituting for carbonate ions in the calcite structure. To address the question of the position of sulfur in biogenic calcites, the oxidation states of sulfur in the skeleton and organic tissues of Corallium rubrum have been investigated by micro X-ray fluorescence (μ-XRF) and sulfur K-edge micro X-ray absorption near edge structure (μ-XANES) spectroscopy at the European Synchrotron Radiation Facility (ESRF, Grenoble, France) on beamline ID21. In the skeleton, sulfur is mainly present as oxidized sulfur SO42- (+VI), plus a weak sulfite contribution. XANES spectra indicate that sulfur is inorganically incorporated as sulfur structurally substituted to carbonate ions (SSS). Although an organic matrix is present in the red coral skeleton, reduced organic sulfur could not be detected by μ-XANES spectroscopy in the skeleton probably due to low organic/inorganic sulfur ratio. In the organic tissues surrounding the skeleton, several sulfur oxidation states have been detected including disulfide (S-S), thioether (R-S-CH3), sulfoxide (SO2), sulfonate (SO2O-) and sulfate (SO42-). The unexpected occurrence of inorganic sulfate within the organic tissues suggests the presence of pre-organized organic/inorganic complexes in the circulatory system of the red coral, precursors to biomineralization ahead of the growth front.

  6. Surface passivation process of compound semiconductor material using UV photosulfidation

    Science.gov (United States)

    Ashby, Carol I. H.

    1995-01-01

    A method for passivating compound semiconductor surfaces by photolytically disrupting molecular sulfur vapor with ultraviolet radiation to form reactive sulfur which then reacts with and passivates the surface of compound semiconductors.

  7. The life sulfuric: microbial ecology of sulfur cycling in marine sediments.

    Science.gov (United States)

    Wasmund, Kenneth; Mußmann, Marc; Loy, Alexander

    2017-08-01

    Almost the entire seafloor is covered with sediments that can be more than 10 000 m thick and represent a vast microbial ecosystem that is a major component of Earth's element and energy cycles. Notably, a significant proportion of microbial life in marine sediments can exploit energy conserved during transformations of sulfur compounds among different redox states. Sulfur cycling, which is primarily driven by sulfate reduction, is tightly interwoven with other important element cycles (carbon, nitrogen, iron, manganese) and therefore has profound implications for both cellular- and ecosystem-level processes. Sulfur-transforming microorganisms have evolved diverse genetic, metabolic, and in some cases, peculiar phenotypic features to fill an array of ecological niches in marine sediments. Here, we review recent and selected findings on the microbial guilds that are involved in the transformation of different sulfur compounds in marine sediments and emphasise how these are interlinked and have a major influence on ecology and biogeochemistry in the seafloor. Extraordinary discoveries have increased our knowledge on microbial sulfur cycling, mainly in sulfate-rich surface sediments, yet many questions remain regarding how sulfur redox processes may sustain the deep-subsurface biosphere and the impact of organic sulfur compounds on the marine sulfur cycle. © 2017 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.

  8. Sulfur-Kβ /sub emission studies on sulfur-bearing heterocycles

    International Nuclear Information System (INIS)

    Phillips, D.R.; Andermann, G.G.; Fujiwara, F.

    1986-01-01

    Sulfur-K/β /sub x-ray fluorescence spectroscopy (XFS) has been used to study the electronic structure and bonding in sulfur-bearing heterocycles. XFS not only has the capability of experimentally measuring valence electron energies in molecular species, but can also provide intensity data which can help define the nature of the molecular orbitals defined by the electrons. This report discusses the feasibility of using XFS as an analytical tool for the determination of total and specific sulfur heterocycle content in samples. A variety of compounds were studied. These include thiophene, thiophene derivatives, tetranydrothiophene, several more complex saturated and unsaturated sulfur heterocycles, and heterocycles containing both sulfur and nitrogen. The sulfur-K/β /sub spectra were obtained using a double crystal spectrometer which provided an instrumental resolution of about 0.7 eV

  9. A novel inorganic-organic compound: Synthesis and structural characterization of tin(II) phenylbis(phosphonate), Sn2(PO3C6H4PO3)

    International Nuclear Information System (INIS)

    Subbiah, Ayyappan; Bhuvanesh, Nattamai; Clearfield, Abraham

    2005-01-01

    A novel tin(II) phenylbis(phosphonate) compound has been synthesized hydrothermally and its structure has been determined by single crystal X-ray diffraction. The structure is monoclinic, space group P2 1 /c (no. 14), a=4.8094(4), b=16.2871(13), c=6.9107(6)A; β=106.292(6) o , V=519.59(7)A 3 , Z=2. The three-dimensional structure consists of 3-coordinated tin and 4-coordinated phosphorus double layers separated (pillared) by phenyl rings. These phenyl rings are placed 4.8A apart along the a-axis in the structure resulting in lower surface area (∼14m 2 /g). The porosity has been increased by replacing phenyl groups by methyl groups (∼31m 2 /g)

  10. Solid-to-solid oxidation of a vanadium(IV) to a vanadium(V) compound: chemisty of a sulfur-containing siderophore.

    Science.gov (United States)

    Chatterjee, Pabitra B; Crans, Debbie C

    2012-09-03

    Visible light facilitates a solid-to-solid photochemical aerobic oxidation of a hunter-green microcrystalline oxidovanadium(IV) compound (1) to form a black powder of cis-dioxidovanadium(V) (2) at ambient temperature. The siderophore ligand pyridine-2,6-bis(thiocarboxylic acid), H(2)L, is secreted by a microorganism from the Pseudomonas genus. This irreversible transformation of a metal monooxo to a metal dioxo complex in the solid state in the absence of solvent is unprecedented. It serves as a proof-of-concept reaction for green chemistry occurring in solid matrixes.

  11. Salicylate-spectrophotometric determination of inorganic monochloramine

    International Nuclear Information System (INIS)

    Tao Hui; Chen Zhonglin; Li Xing; Yang Yanling; Li Guibai

    2008-01-01

    On the basis of classical Berthelot reaction, a simple salicylate-spectrophotometric method was developed for quantitative determination of inorganic monochloramine in water samples. With the catalysis of disodium pentacyanonitrosylferrate(III), inorganic monochloramine reacts with salicylate in equimolar to produce indophenol compound which has an intense absorption at 703 nm. Parameters that influence method performance, such as pH, dosage of salicylate and nitroprussiate and reaction time, were modified to enhance the method performance. By using this method, inorganic monochloramine can be distinguished from organic chloramines and other inorganic chlorine species, such as free chlorine, dichloramine, and trichloramine. The molar absorptivities of the final products formed by these compounds are below ±3% of inorganic monochloramine, because of the α-N in them have only one exchangeable hydrogen atom, and cannot react with salicylate to produce the indophenol compound. The upper concentrations of typical ions that do not interfere with the inorganic monochloramine determination are also tested to be much higher than that mostly encountered in actual water treatment. Case study demonstrates that the results obtained from this method are lower than DPD-titrimetric method because the organic chloramines formed by chlorination of organic nitrogenous compounds give no response in the newly established method. And the result measured by salicylate-spectrophotometric method is coincident with theoretical calculation

  12. In situ tribochemical sulfurization of molybdenum oxide nanotubes.

    Science.gov (United States)

    Rodríguez Ripoll, Manel; Tomala, Agnieszka; Gabler, Christoph; DraŽić, Goran; Pirker, Luka; Remškar, Maja

    2018-02-15

    MoS 2 nanoparticles are typically obtained by high temperature sulfurization of organic and inorganic precursors under a S rich atmosphere and have excellent friction reduction properties. We present a novel approach for making the sulfurization unnecessary for MoO 3 nanotubes during the synthesis process for friction and wear reduction applications while simultaneously achieving a superb tribological performance. To this end, we report the first in situ sulfurization of MoO 3 nanotubes during sliding contact in the presence of sulfur-containing lubricant additives. The sulfurization leads to the tribo-chemical formation of a MoS 2 -rich low-friction tribofilm as verified using Raman spectroscopy and can be achieved both during sliding contact and under extreme pressure conditions. Under sliding contact conditions, MoO 3 nanotubes in synergy with sulfurized olefin polysulfide and pre-formed zinc dialkyl dithiophosphate tribofilms achieve an excellent friction performance. Under these conditions, the tribochemical sulfurization of MoO 3 nanotubes leads to a similar coefficient of friction to the one obtained using a model nanolubricant containing MoS 2 nanotubes. Under extreme pressure conditions, the in situ sulfurization of MoO 3 nanotubes using sulfurized olefin polysulfide results in a superb load carrying capacity capable of outperforming MoS 2 nanotubes. The reason is that while MoO 3 nanotubes are able to continuously sulfurize during sliding contact conditions, MoS 2 nanotubes progressively degrade by oxidation thus losing lubricity.

  13. Isolation and characterization of a sulfur-oxidizing chemolithotroph growing on crude oil under anaerobic conditions.

    Science.gov (United States)

    Kodama, Yumiko; Watanabe, Kazuya

    2003-01-01

    Molecular approaches have shown that a group of bacteria (called cluster 1 bacteria) affiliated with the epsilon subclass of the class Proteobacteria constituted major populations in underground crude-oil storage cavities. In order to unveil their physiology and ecological niche, this study isolated bacterial strains (exemplified by strain YK-1) affiliated with the cluster 1 bacteria from an oil storage cavity at Kuji in Iwate, Japan. 16S rRNA gene sequence analysis indicated that its closest relative was Thiomicrospira denitrificans (90% identity). Growth experiments under anaerobic conditions showed that strain YK-1 was a sulfur-oxidizing obligate chemolithotroph utilizing sulfide, elemental sulfur, thiosulfate, and hydrogen as electron donors and nitrate as an electron acceptor. Oxygen also supported its growth only under microaerobic conditions. Strain YK-1 could not grow on nitrite, and nitrite was the final product of nitrate reduction. Neither sugars, organic acids (including acetate), nor hydrocarbons could serve as carbon and energy sources. A typical stoichiometry of its energy metabolism followed an equation: S(2-) + 4NO(3)(-) --> SO(4)(2-) + 4NO(2)(-) (Delta G(0) = -534 kJ mol(-1)). In a difference from other anaerobic sulfur-oxidizing bacteria, this bacterium was sensitive to NaCl; growth in medium containing more than 1% NaCl was negligible. When YK-1 was grown anaerobically in a sulfur-depleted inorganic medium overlaid with crude oil, sulfate was produced, corresponding to its growth. On the contrary, YK-1 could not utilize crude oil as a carbon source. These results suggest that the cluster 1 bacteria yielded energy for growth in oil storage cavities by oxidizing petroleum sulfur compounds. Based on its physiology, ecological interactions with other members of the groundwater community are discussed.

  14. Sulfur removal from low-sulfur gasoline and diesel fuel by metal-organic frameworks

    Energy Technology Data Exchange (ETDEWEB)

    Hagen, G.; Haemmerle, M.; Moos, R. [Functional Materials, University of Bayreuth, Bayreuth (Germany); Malkowsky, I.M.; Kiener, C. [BASF SE, Ludwigshafen (Germany); Achmann, S.

    2010-02-15

    Several materials in the class of metal-organic frameworks (MOF) were investigated to determine their sorption characteristics for sulfur compounds from fuels. The materials were tested using different model oils and common fuels such as low-sulfur gasoline or diesel fuel at room temperature and ambient pressure. Thiophene and tetrahydrothiophene (THT) were chosen as model substances. Total-sulfur concentrations in the model oils ranged from 30 mg/kg (S from thiophene) to 9 mg/kg (S from tetrahydrothiophene) as determined by elementary analysis. Initial sulfur contents of 8 mg/kg and 10 mg/kg were identified for low-sulfur gasoline and for diesel fuel, respectively, by analysis of the common liquid fuels. Most of the MOF materials examined were not suitable for use as sulfur adsorbers. However, a high efficiency for sulfur removal from fuels and model oils was noticed for a special copper-containing MOF (copper benzene-1,3,5-tricarboxylate, Cu-BTC-MOF). By use of this material, 78 wt % of the sulfur content was removed from thiophene containing model oils and an even higher decrease of up to 86 wt % was obtained for THT-based model oils. Moreover, the sulfur content of low-sulfur gasoline was reduced to 6.5 mg/kg, which represented a decrease of more than 22 %. The sulfur level in diesel fuel was reduced by an extent of 13 wt %. Time-resolved measurements demonstrated that the sulfur-sorption mainly occurs in the first 60 min after contact with the adsorbent, so that the total time span of the desulfurization process can be limited to 1 h. Therefore, this material seems to be highly suitable for sulfur reduction in commercial fuels in order to meet regulatory requirements and demands for automotive exhaust catalysis-systems or exhaust gas sensors. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  15. Microbial Desulfurization of a Crude Oil Middle-Distillate Fraction: Analysis of the Extent of Sulfur Removal and the Effect of Removal on Remaining Sulfur

    Science.gov (United States)

    Grossman, M. J.; Lee, M. K.; Prince, R. C.; Garrett, K. K.; George, G. N.; Pickering, I. J.

    1999-01-01

    Rhodococcus sp. strain ECRD-1 was evaluated for its ability to desulfurize a 232 to 343°C middle-distillate (diesel range) fraction of Oregon basin (OB) crude oil. OB oil was provided as the sole source of sulfur in batch cultures, and the extent of desulfurization and the chemical fate of the residual sulfur in the oil after treatment were determined. Gas chromatography (GC), flame ionization detection, and GC sulfur chemiluminesce detection analysis were used to qualitatively evaluate the effect of Rhodococcus sp. strain ECRD-1 treatment on the hydrocarbon and sulfur content of the oil, respectively. Total sulfur was determined by combustion of samples and measurement of released sulfur dioxide by infrared absorption. Up to 30% of the total sulfur in the middle distillate cut was removed, and compounds across the entire boiling range of the oil were affected. Sulfur K-edge X-ray absorption-edge spectroscopy was used to examine the chemical state of the sulfur remaining in the treated OB oil. Approximately equal amounts of thiophenic and sulfidic sulfur compounds were removed by ECRD-1 treatment, and over 50% of the sulfur remaining after treatment was in an oxidized form. The presence of partially oxidized sulfur compounds indicates that these compounds were en route to desulfurization. Overall, more than two-thirds of the sulfur had been removed or oxidized by the microbial treatment. PMID:9872778

  16. Extractive de-sulfurization and de-ashing of high sulfur coals by oxidation with ionic liquids

    International Nuclear Information System (INIS)

    Saikia, Binoy K.; Khound, Kakoli; Baruah, Bimala P.

    2014-01-01

    Highlights: • Extractive de-sulfurization and de-ashing process for cleaning high sulfur coals. • The process removes inorganic as well as organic sulfur components from high sulfur coals. • The process has less risk to chemists and other surroundings. - Abstract: The environmental consequences of energy production from coals are well known, and are driving the development of desulfurization technologies. In this investigation, ionic liquids were examined for extractive desulfurization and de-ashing in industrially important high sulfur sub-bituminous Indian coals. The ionic liquids, namely, 1-n-butyl-3-methylimidazolium tetrafluoroborate (IL1) and 1-n-butyl 3-methylimidazolium chloride (IL2) were employed for desulfurization of a few Indian coal samples in presence of HCOOH/H 2 O 2 and V 2 O 5 . Results show the maximum removal of 50.20% of the total sulfur, 48.00% of the organic sulfur, and 70.37 wt% of the ash in this process. The ionic liquids were recovered and subsequently used for further desulfurization. FT-IR spectra reveal the transformation of organic sulfur functionalities into the sulfoxides (S=O) and sulfones (-SO 2 ) due to the oxidative reactions. The sulfate, pyrite and sulfides (aryls) signals in the near edge X-ray absorption fine structure (NEXAFS) of the oxidized coal samples showed sulfur transformation during the desulfurization process. The study demonstrates the removal of significant amount of inorganic as well as organic sulfur (aryls) components from the original high sulfur coal samples to make them cleaner

  17. Resolution and chemical formula identification of aromatic hydrocarbons and aromatic compounds containing sulfur, nitrogen, or oxygen in petroleum distillates and refinery streams.

    Science.gov (United States)

    Guan, S; Marshall, A G; Scheppele, S E

    1996-01-01

    that FT-ICR is the mass analysis of choice for differentiating hydrocarbons from heteroatom-containing compounds in petroleum distillates and refinery streams.

  18. Sulfur deactivation of fatty ester hydrogenolysis catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Brands, D.S.; U-A-Sai, G.; Poels, E.K.; Bliek, A. [Univ. of Amsterdam (Netherlands). Dept. of Chemical Engineering

    1999-08-15

    Trace organosulfur compounds present as natural impurities in oleochemical feedstocks may lead to activation of copper-containing catalysts applied for hydrogenolysis of esters toward fatty alcohols. In this paper, the sulfur deactivation of Cu/SiO{sub 2} and Cu/ZnO/SiO{sub 2} catalysts was studied in the liquid-phase hydrogenolysis of methyl palmitate. The rate of deactivation is fast and increases as a function of the sulfur-containing compound present: octadecanethiol {approx} dihexadecyl disulfide < benzyl isothiocyanate < methyl p-toluene sulfonate < dihexadecyl sulfide < dibenzothiophene. The rapid deactivation is caused by the fact that sulfur is quantitatively removed from the reaction mixture and because mainly surface sulfides are formed under hydrogenolysis conditions. The life time of a zinc-promoted catalyst is up to two times higher than that of the Cu/SiO{sub 2} catalyst, most likely due to zinc surface sulfide formation. The maximum sulfur coverage obtained after full catalyst deactivation with dibenzothiophene and dihexadecyl sulfide--the sulfur compounds that cause the fastest deactivation--may be as low as 0.07. This is due to the fact that decomposition of these compounds as well as the hydrogenolysis reaction itself proceeds on ensembles of copper atoms. Catalyst regeneration studies reveal that activity cannot be regained by reduction or combined oxidation/reduction treatments. XRD, TPR, and TPO results confirm that no distinct bulk copper or zinc sulfide or sulfate phases are present.

  19. Radiation induced sulfur dioxide removal

    International Nuclear Information System (INIS)

    Chmielewski, A.G.

    2000-01-01

    The biggest source of air pollution is the combustion of fossil fuels, were pollutants such as particulate, sulfur dioxide (SO 2 ), nitrogen oxides (NO x ), and volatile organic compounds (VOC) are emitted. Among these pollutants, sulfur dioxide plays the main role in acidification of the environment. The mechanism of sulfur dioxide transformation in the environment is partly photochemical. This is not direct photooxidation, however, but oxidation through formed radicals. Heterogenic reactions play an important role in this transformation as well; therefore, observations from environmental chemistry can be used in air pollution control engineering. One of the most promising technologies for desulfurization of the flue gases (and simultaneous denitrification) is radiation technology with an electron accelerator application. Contrary to the nitrogen oxides (NO x ) removal processes, which is based on pure radiation induced reactions, sulfur dioxide removal depends on two pathways: a thermochemical reaction in the presence of ammonia/water vapor and a radiation set of radiochemical reactions. The mechanism of these reactions and the consequent technological parameters of the process are discussed in this paper. The industrial application of this radiation technology is being implemented in an industrial pilot plant operated by INCT at EPS Kaweczyn. A full-scale industrial plant is currently in operation in China, and two others are under development in Japan and Poland. (author)

  20. Sulfur dimers adsorbed on Au(111) as building blocks for sulfur octomers formation: A density functional study

    International Nuclear Information System (INIS)

    Hernandez-Tamargo, Carlos E.; Montero-Alejo, Ana Lilian; Pujals, Daniel Codorniu; Mikosch, Hans; Hernández, Mayra P.

    2014-01-01

    Experimental scanning tunneling microscopy (STM) studies have shown for more than two decades rectangular formations when sulfur atoms are deposited on Au(111) surfaces. The precursors have ranged from simple molecules or ions, such as SO 2 gas or sulfide anions, to more complex organosulfur compounds. We investigated, within the framework of the Density Functional Theory, the structure of these rectangular patterns assuming them entirely composed of sulfur atoms as the experimental evidence suggests. The sulfur coverage at which the simulations were carried out (0.67 ML or higher) provoked that the sulfur-sulfur association had to be taken into account for achieving a good agreement between the sets of simulated and experimental STM images. A combination of four sulfur dimers per rectangular formation properly explained the trends obtained by the experimental STM analysis which were related with the rectangles' size and shape fluctuations together with sulfur-sulfur distances within these rectangles. Finally, a projected density of states analysis showed that the dimers were capable of altering the Au(5d) electronic states at the same level as atomic sulfur adsorbed at low coverage. Besides, sulfur dimers states were perfectly distinguished, whose presence near and above the Fermi level can explain both: sulfur-sulfur bond elongation and dimers stability when they stayed adsorbed on the surface at high coverage

  1. Sulfur dimers adsorbed on Au(111) as building blocks for sulfur octomers formation: A density functional study

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez-Tamargo, Carlos E.; Montero-Alejo, Ana Lilian [Laboratory of Computational and Theoretical Chemistry (LQCT), Faculty of Chemistry, Havana University, Havana 10400 (Cuba); Pujals, Daniel Codorniu [Higher Institute of Technologies and Applied Sciences (InSTEC), Havana 10400 (Cuba); Mikosch, Hans [Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/E164-EC, 1060 Vienna (Austria); Hernández, Mayra P., E-mail: mayrap@imre.oc.uh.cu [Instituto de Ciencias y Tecnologías de Materiales (IMRE), Havana 10400 (Cuba)

    2014-07-28

    Experimental scanning tunneling microscopy (STM) studies have shown for more than two decades rectangular formations when sulfur atoms are deposited on Au(111) surfaces. The precursors have ranged from simple molecules or ions, such as SO{sub 2} gas or sulfide anions, to more complex organosulfur compounds. We investigated, within the framework of the Density Functional Theory, the structure of these rectangular patterns assuming them entirely composed of sulfur atoms as the experimental evidence suggests. The sulfur coverage at which the simulations were carried out (0.67 ML or higher) provoked that the sulfur-sulfur association had to be taken into account for achieving a good agreement between the sets of simulated and experimental STM images. A combination of four sulfur dimers per rectangular formation properly explained the trends obtained by the experimental STM analysis which were related with the rectangles' size and shape fluctuations together with sulfur-sulfur distances within these rectangles. Finally, a projected density of states analysis showed that the dimers were capable of altering the Au(5d) electronic states at the same level as atomic sulfur adsorbed at low coverage. Besides, sulfur dimers states were perfectly distinguished, whose presence near and above the Fermi level can explain both: sulfur-sulfur bond elongation and dimers stability when they stayed adsorbed on the surface at high coverage.

  2. Sulfur poisoning in cattle

    Energy Technology Data Exchange (ETDEWEB)

    Julian, R J; Harrison, K B

    1975-01-01

    A case of sulfur poisoning is described in which 12 of 20 cattle died following the feeding of sulfur. Respiratory distress and abdominal pain were the prominent signs. Examination of one animal revealed vasculitis and necrosis of the rumen and abomasal wall. The possible toxic effects of sulfur are discussed.

  3. Assessment of ethylene dibromide, dibromochloropropane, other volatile organic compounds, radium isotopes, radon, and inorganic compounds in groundwater and spring water from the Crouch Branch and McQueen Branch aquifers near McBee, South Carolina, 2010-2012

    Science.gov (United States)

    Landmeyer, James E.; Campbell, Bruce G.

    2014-01-01

    Public-supply wells near the rural town of McBee, in southwestern Chesterfield County, South Carolina, have provided potable water to more than 35,000 residents throughout Chesterfield County since the early 1990s. Groundwater samples collected between 2002 and 2008 in the McBee area by South Carolina Department of Health and Environmental Control (DHEC) officials indicated that groundwater from two public-supply wells was characterized by the anthropogenic compounds ethylene dibromide (EDB) and dibromochloropropane (DBCP) at concentrations that exceeded their respective maximum contaminant levels (MCLs) established by the U.S. Environmental Protection Agency’s (EPA) National Primary Drinking Water Regulations (NPDWR). Groundwater samples from all public-supply wells in the McBee area were characterized by the naturally occurring isotopes of radium-226 and radium-228 at concentrations that approached, and in one well exceeded, the MCL for the combined isotopes. The local water utility installed granulated activated carbon filtration units at the two EDB- and DBCP-contaminated wells and has, since 2011, shut down these two wells. Groundwater pumped by the remaining public-supply wells is currently (2014) centrally treated at a water-filtration plant.

  4. Genomic Insights into the Sulfur Metabolism of Phototrophic Green Sulfur Bacteria

    DEFF Research Database (Denmark)

    Frigaard, Niels-Ulrik; Bryant, Donald A.

    2008-01-01

    Green sulfur bacteria (GSB) utilize various combinations of sulfide, elemental sulfur, thiosulfate, ferrous iron, and hydrogen for anaerobic photoautotrophic growth. Genome sequence data is currently available for 12 strains of GSB. We present here a genome-based survey of the distribution...... and phylogenies of genes involved in oxidation of sulfur compounds in these strains. Sulfide:quinone reductase, encoded by sqr, is the only known sulfur-oxidizing enzyme found in all strains. All sulfide-utilizing strains contain the dissimilatory sulfite reductase dsrABCEFHLNMKJOPT genes, which appear...... to be involved in elemental sulfur utilization. All thiosulfate-utilizing strains have an identical sox gene cluster (soxJXYZAKBW). The soxCD genes found in certain other thiosulfate-utilizing organisms like Paracoccus pantotrophus are absent from GSB. Genes encoding flavocytochrome c (fccAB), adenosine-5...

  5. K- and L-edge X-ray absorption spectrum calculations of closed-shell carbon, silicon, germanium, and sulfur compounds using damped four-component density functional response theory.

    Science.gov (United States)

    Fransson, Thomas; Burdakova, Daria; Norman, Patrick

    2016-05-21

    X-ray absorption spectra of carbon, silicon, germanium, and sulfur compounds have been investigated by means of damped four-component density functional response theory. It is demonstrated that a reliable description of relativistic effects is obtained at both K- and L-edges. Notably, an excellent agreement with experimental results is obtained for L2,3-spectra-with spin-orbit effects well accounted for-also in cases when the experimental intensity ratio deviates from the statistical one of 2 : 1. The theoretical results are consistent with calculations using standard response theory as well as recently reported real-time propagation methods in time-dependent density functional theory, and the virtues of different approaches are discussed. As compared to silane and silicon tetrachloride, an anomalous error in the absolute energy is reported for the L2,3-spectrum of silicon tetrafluoride, amounting to an additional spectral shift of ∼1 eV. This anomaly is also observed for other exchange-correlation functionals, but it is seen neither at other silicon edges nor at the carbon K-edge of fluorine derivatives of ethene. Considering the series of molecules SiH4-XFX with X = 1, 2, 3, 4, a gradual divergence from interpolated experimental ionization potentials is observed at the level of Kohn-Sham density functional theory (DFT), and to a smaller extent with the use of Hartree-Fock. This anomalous error is thus attributed partly to difficulties in correctly emulating the electronic structure effects imposed by the very electronegative fluorines, and partly due to inconsistencies in the spurious electron self-repulsion in DFT. Substitution with one, or possibly two, fluorine atoms is estimated to yield small enough errors to allow for reliable interpretations and predictions of L2,3-spectra of more complex and extended silicon-based systems.

  6. Medicinal Uses of Inorganic Compounds - 2

    Indian Academy of Sciences (India)

    and diabetic control, neurological, cardiovascular and in- flammatory diseases. ... Fosrenol binds to dietary phosphate in the stomach and reduces .... Future Perspective. The peptides labeled with different radionuclides (99mTc, 11lln ,.

  7. Medicinal Uses of Inorganic Compounds - 1

    Indian Academy of Sciences (India)

    cardio vascular and insulin-mimetic agents. ... applications for the treatment of a wide variety of human ail- ments. ... discovery of metal-based drugs to treat syphilis. Now, metal! ..... opathy where multifocal necrosis and fibrosis of the myocar-.

  8. Stereochemistry of organometallic and inorganic compounds

    CERN Document Server

    2012-01-01

    The authors of this fourth volume in the series have reviewed the making and breaking of chemical bonds in a sophisticated manner. In particular, new pressures brought about by environmental concerns, larger demands for the medical and pharmaceutical sectors and economics of the market place are forcing us into demanding greater stereochemical control and better product yields for chemical reactions capable of producing useful products. The chapters are written by leading experts in this area and give excellent overviews of the strengths and weaknesses of the various methodologies.In C

  9. Saline-water bioleaching of chalcopyrite with thermophilic, iron(II)- and sulfur-oxidizing microorganisms.

    Science.gov (United States)

    Watling, Helen R; Collinson, David M; Corbett, Melissa K; Shiers, Denis W; Kaksonen, Anna H; Watkin, Elizabeth L J

    2016-09-01

    The application of thermoacidophiles for chalcopyrite (CuFeS2) bioleaching in hot, acidic, saline solution was investigated as a possible process route for rapid Cu extraction. The study comprised a discussion of protective mechanisms employed for the survival and/or adaptation of thermoacidophiles to osmotic stress, a compilation of chloride tolerances for three genera of thermoacidophiles applied in bioleaching and an experimental study of the activities of three species in a saline bioleaching system. The data showed that the oxidation rates of iron(II) and reduced inorganic sulfur compounds (tetrathionate) were reduced in the presence of chloride levels well below chloride concentrations in seawater, limiting the applicability of these microorganisms in the bioleaching of CuFeS2 in saline water. Copyright © 2016. Published by Elsevier Masson SAS.

  10. Sulfur isotope in nature. Determination of sulfur isotope ratios in coal and petroleum by mass spectrometry

    International Nuclear Information System (INIS)

    Derda, M.

    1999-01-01

    Elementary sulfur or in chemical compounds is one of the elements widespread in the earth's crust and biosphere. Its participation in earth's crust amounts to 0.26 % by weight. Measurement of isotope composition of natural samples can deliver many information about origin, creation and transformation ranges of rocks and minerals. Sulfur isotope ratio contained in minerals is variable and for this reason investigation of isotope sulfur composition can deliver useful information about the geochemistry of each component. Therefore in the investigated sample it is necessary to determine not only the content of sulfur but also the isotope composition of each component. Differentiation of contents of sulfur-34 in natural sulfur compounds can reach up to 110 per mile. So large divergences can be explained by a kinetic effect or by bacterial reduction of sulphates. In this report a wide review of the results of investigations of isotope sulfur compositions in coal and petroleum are presented as well as the methods for the preparation of samples for mass spectrometry analysis are proposed. (author)

  11. Genomic and Evolutionary Perspectives on Sulfur Metabolism in Green Sulfur Bacteria

    DEFF Research Database (Denmark)

    Frigaard, Niels-Ulrik; Bryant, Donald A.

    2008-01-01

    Green sulfur bacteria (GSB) are anaerobic photoautotrophs that oxidize sulfide, elemental sulfur, thiosulfate, ferrous iron, and hydrogen for growth. We present here an analysis of the distribution and evolution of enzymes involved in oxidation of sulfur compounds in GSB based on genome sequence......, in combination with phylogenetic analyses, suggests that the Dsr system in GSB could be a recent acquisition, which was obtained by lateral gene transfer in part from sulfideoxidizing bacteria and in part from sulfate-reducing bacteria. All thiosulfate-utilizing GSB strains have an identical sox gene cluster...

  12. Sulfur in human nutrition - effects beyond protein synthesis

    NARCIS (Netherlands)

    Gertjan Schaafsma

    2008-01-01

    That sulfur is essential to humans is based on the requirement of S-animo acids for normal growth and maintenance of nitrogen balance and not on the optimization of metabolic proccesses involving the synthesis of non-protein sulphur containing compounds. This paper reviews the significance of sulfur

  13. Synthesis and characterization of N-t-BOC protected pyrrole-sulfur oligomers and polymers

    NARCIS (Netherlands)

    Groenendaal, L.; Pieterse, K.; Vekemans, J.A.J.M.; Meijer, E.W.

    1997-01-01

    The synthesis and characterization of a new class of pyrrole-sulfur compounds is described. These compounds are designed to be precursors for an organic analogue of poly(sulfur nitride). Poly(N-t-BOC-2.5-pyrrolyl sulfide) was prepared from N-t-BOC-2,5-dibromopyrrole by first lithiating this compound

  14. An overview of the bioremediation of inorganic contaminants

    International Nuclear Information System (INIS)

    Bolton, H. Jr.; Gorby, Y.A.

    1995-01-01

    Bioremediation, or the biological treatment of wastes, usually is associated with the remediation of organic contaminants. Similarly, there is an increasing body of literature and expertise in applying biological systems to assist in the bioremediation of soils, sediments, and water contaminated with inorganic compounds including metals, radionuclides, nitrates, and cyanides. Inorganic compounds can be toxic both to humans and to organisms used to remediate these contaminants. However, in contrast to organic contaminants, most inorganic contaminants cannot be degraded, but must be remediated by altering their transport properties. Immobilization, mobilization, or transformation of inorganic contaminants via bioaccumulation, biosorption, oxidation, reduction, methylation, demethylation, metal-organic complexation, ligand degradation, and phytoremediation are the various processes applied in the bioremediation of inorganic compounds. This paper briefly describes these processes, referring to other contributors in this book as examples when possible, and summarize the factors that must be considered when choosing bioremediation as a cleanup technology for inorganics. Understanding the current state of knowledge as well as the limitations for bioremediation of inorganic compounds will assist in identifying and implementing successful remediation strategies at sites containing inorganic contaminants. 79 refs

  15. Sulfur polymer cement concrete

    International Nuclear Information System (INIS)

    Weber, H.H.; McBee, W.C.

    1990-01-01

    Sulfur-based composite materials formulated using sulfur polymer cement (SPC) and mineral aggregates are described and compared with conventional portland cement based materials. Materials characteristics presented include mechanical strength, chemical resistance, impact resistance, moisture permeation, and linear shrinkage during placement and curing. Examples of preparation and placement of sulfur polymer cement concrete (SC) are described using commercial scale equipment. SC applications presented are focused into hostile chemical environments where severe portland cement concrete (PCC) failure has occurred

  16. Sulfur K-edge absorption spectroscopy on selected biological systems

    International Nuclear Information System (INIS)

    Lichtenberg, Henning

    2008-07-01

    Sulfur is an essential element in organisms. In this thesis investigations of sulfur compounds in selected biological systems by XANES (X-ray Absorption Near Edge Structure) spectroscopy are reported. XANES spectroscopy at the sulfur K-edge provides an excellent tool to gain information about the local environments of sulfur atoms in intact biological samples - no extraction processes are required. Spatially resolved measurements using a Kirkpatrick-Baez mirror focusing system were carried out to investigate the infection of wheat leaves by rust fungi. The results give information about changes in the sulfur metabolism of the host induced by the parasite and about the extension of the infection into visibly uninfected plant tissue. Furthermore, XANES spectra of microbial mats from sulfidic caves were measured. These mats are dominated by microbial groups involved in cycling sulfur. Additionally, the influence of sulfate deprivation and H 2 S exposure on sulfur compounds in onion was investigated. To gain an insight into the thermal degradation of organic material the influence of roasting of sulfur compounds in coffee beans was studied. (orig.)

  17. Genotypic variation in the sulfur assimilation and metabolism of onion (Allium cepa L.) I. Plant composition and transcript accumulation

    KAUST Repository

    McCallum, John A.; Thomas, Ludivine; Shaw, Martin L.; Pither-Joyce, Meeghan D.; Leung, Susanna; Cumming, Mathew; McManus, Michael T.

    2011-01-01

    Organosulfur compounds are major sinks for assimilated sulfate in onion (Allium cepa L.) and accumulation varies widely due to plant genotype and sulfur nutrition. In order to better characterise sulfur metabolism phenotypes and identify potential

  18. Development of enhanced sulfur rejection processes

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, R.H.; Luttrell, G.H.; Adel, G.T.; Richardson, P.E.

    1996-03-01

    Research at Virginia Tech led to the development of two complementary concepts for improving the removal of inorganic sulfur from many eastern U.S. coals. These concepts are referred to as Electrochemically Enhanced Sulfur Rejection (EESR) and Polymer Enhanced Sulfur Rejection (PESR) processes. The EESR process uses electrochemical techniques to suppress the formation of hydrophobic oxidation products believed to be responsible for the floatability of coal pyrite. The PESR process uses polymeric reagents that react with pyrite and convert floatable middlings, i.e., composite particles composed of pyrite with coal inclusions, into hydrophilic particles. These new pyritic-sulfur rejection processes do not require significant modifications to existing coal preparation facilities, thereby enhancing their adoptability by the coal industry. It is believed that these processes can be used simultaneously to maximize the rejection of both well-liberated pyrite and composite coal-pyrite particles. The project was initiated on October 1, 1992 and all technical work has been completed. This report is based on the research carried out under Tasks 2-7 described in the project proposal. These tasks include Characterization, Electrochemical Studies, In Situ Monitoring of Reagent Adsorption on Pyrite, Bench Scale Testing of the EESR Process, Bench Scale Testing of the PESR Process, and Modeling and Simulation.

  19. Parameters Influencing Sulfur Speciation in Environmental Samples Using Sulfur K-Edge X-Ray Absorption Near-Edge Structure

    Directory of Open Access Journals (Sweden)

    Siwatt Pongpiachan

    2012-01-01

    Full Text Available This paper aims to enhance the credibility of applying the sulfur K-edge XANES spectroscopy as an innovative “fingerprint” for characterizing environmental samples. The sensitivities of sulfur K-edge XANES spectra of ten sulfur compound standards detected by two different detectors, namely, Lytle detector (LyD and Germanium detector (GeD, were studied and compared. Further investigation on “self-absorption” effect revealed that the maximum sensitivities of sulfur K-edge XANES spectra were achieved when diluting sulfur compound standards with boron nitride (BN at the mixing ratio of 0.1%. The “particle-size” effect on sulfur K-edge XANES spectrum sensitivities was examined by comparing signal-to-noise ratios of total suspended particles (TSP and particulate matter of less than 10 millionths of a meter (PM10 collected at three major cities of Thailand. The analytical results have demonstrated that the signal-to-noise ratios of sulfur K-edge XANES spectra were positively correlated with sulfate content in aerosols and negatively connected with particle sizes. The combination of hierarchical cluster analysis (HCA and principal component analysis (PCA has proved that sulfur K-edge XANES spectrum can be used to characterize German terrestrial soils and Andaman coastal sediments. In addition, this study highlighted the capability of sulfur K-edge XANES spectra as an innovative “fingerprint” to distinguish tsunami backwash deposits (TBD from typical marine sediments (TMS.

  20. Elemental sulfur and thiosulfate disproportionation by Desulfocapsa sulfoexigens sp. nov., a new anaerobic bacterium isolated from marine surface sediment.

    Science.gov (United States)

    Finster, K; Liesack, W; Thamdrup, B

    1998-01-01

    A mesophilic, anaerobic, gram-negative bacterium, strain SB164P1, was enriched and isolated from oxidized marine surface sediment with elemental sulfur as the sole energy substrate in the presence of ferrihydrite. Elemental sulfur was disproportionated to hydrogen sulfide and sulfate. Growth was observed exclusively in the presence of a hydrogen sulfide scavenger, e.g., ferrihydrite. In the absence of a scavenger, sulfide and sulfate production were observed but no growth occurred. Strain SB164P1 grew also by disproportionation of thiosulfate and sulfite. With thiosulfate, the growth efficiency was higher in ferrihydrite-supplemented media than in media without ferrihydrite. Growth coupled to sulfate reduction was not observed. However, a slight sulfide production occurred in cultures incubated with formate and sulfate. Strain SB164P1 is the first bacterium described that grows chemolithoautotrophically exclusively by the disproportionation of inorganic sulfur compounds. Comparative 16S rDNA sequencing analysis placed strain SB164P1 into the delta subclass of the class Proteobacteria. Its closest relative is Desulfocapsa thiozymogenes, and slightly more distantly related are Desulfofustis glycolicus and Desulforhopalus vacuolatus. This phylogenetic cluster of organisms, together with members of the genus Desulfobulbus, forms one of the main lines of descent within the delta subclass of the Proteobacteria. Due to the common phenotypic characteristics and the phylogenetic relatedness to Desulfocapsa thiozymogenes, we propose that strain SB164P1 be designated the type strain of Desulfocapsa sulfoexigens sp. nov.

  1. A review of the inorganic and organometallic chemistry of zirconium

    International Nuclear Information System (INIS)

    Kalvins, A.K.

    1985-01-01

    The results of a literature review of the inorganic and organometallic chemistry of zirconium are presented. Compounds with physical and chemical properties compatible with the requirements of an ir laser zirconium isotope separation process have been identified

  2. ADVANCED SULFUR CONTROL CONCEPTS

    Energy Technology Data Exchange (ETDEWEB)

    Apostolos A. Nikolopoulos; Santosh K. Gangwal; William J. McMichael; Jeffrey W. Portzer

    2003-01-01

    Conventional sulfur removal in integrated gasification combined cycle (IGCC) power plants involves numerous steps: COS (carbonyl sulfide) hydrolysis, amine scrubbing/regeneration, Claus process, and tail-gas treatment. Advanced sulfur removal in IGCC systems involves typically the use of zinc oxide-based sorbents. The sulfides sorbent is regenerated using dilute air to produce a dilute SO{sub 2} (sulfur dioxide) tail gas. Under previous contracts the highly effective first generation Direct Sulfur Recovery Process (DSRP) for catalytic reduction of this SO{sub 2} tail gas to elemental sulfur was developed. This process is currently undergoing field-testing. In this project, advanced concepts were evaluated to reduce the number of unit operations in sulfur removal and recovery. Substantial effort was directed towards developing sorbents that could be directly regenerated to elemental sulfur in an Advanced Hot Gas Process (AHGP). Development of this process has been described in detail in Appendices A-F. RTI began the development of the Single-step Sulfur Recovery Process (SSRP) to eliminate the use of sorbents and multiple reactors in sulfur removal and recovery. This process showed promising preliminary results and thus further process development of AHGP was abandoned in favor of SSRP. The SSRP is a direct Claus process that consists of injecting SO{sub 2} directly into the quenched coal gas from a coal gasifier, and reacting the H{sub 2}S-SO{sub 2} mixture over a selective catalyst to both remove and recover sulfur in a single step. The process is conducted at gasifier pressure and 125 to 160 C. The proposed commercial embodiment of the SSRP involves a liquid phase of molten sulfur with dispersed catalyst in a slurry bubble-column reactor (SBCR).

  3. Io's theothermal (sulfur) - Lithosphere cycle inferred from sulfur solubility modeling of Pele's magma supply

    Science.gov (United States)

    Battaglia, Steven M.; Stewart, Michael A.; Kieffer, Susan W.

    2014-06-01

    Surface deposits of volatile compounds such as water (Earth) or sulfur (Io) on volcanically active bodies suggest that a magmatic distillation process works to concentrate volatiles in surface reservoirs. On Earth, this is the combined hydrologic and tectonic cycle. On Io, sulfurous compounds are transferred from the interior to the surface reservoirs through a combination of a mantle-sourced magmatic system, vertical cycling of the lithosphere, and a sulfur-dominated crustal thermal system that we here call the "theothermal" system. We present a geochemical analysis of this process using previously inferred temperature and oxygen fugacity constraints of Pele's basaltic magma to determine the behavior of sulfur in the ionian magmas. Sulfate to sulfide ratios of Pele's magma are -4.084 ± 0.6 and -6.442 ± 0.7 log10 units, comparable to or lower than those of mid-ocean ridge basalts. This reflects the similarity of Io's oxidation state with Earth's depleted mantle as previously suggested by Zolotov and Fegley (Zolotov, M.Y., Fegley, B. [2000]. Geophys. Res. Lett. 27, 2789-2792). Our calculated limits of sulfur solubility in melts from Pele's patera (˜1100-1140 ppm) are also comparable to terrestrial mid-ocean ridge basalts, reflecting a compositional similarity of mantle sources. We propose that the excess sulfur obvious on Io's surface comes from two sources: (1) an insoluble sulfide liquid phase in the magma and (2) theothermal near-surface recycling.

  4. Inorganic nanolayers: structure, preparation, and biomedical applications.

    Science.gov (United States)

    Saifullah, Bullo; Hussein, Mohd Zobir B

    2015-01-01

    Hydrotalcite-like compounds are two-dimensional inorganic nanolayers also known as clay minerals or anionic clays or layered double hydroxides/layered hydroxy salts, and have emerged as a single type of material with numerous biomedical applications, such as drug delivery, gene delivery, cosmetics, and biosensing. Inorganic nanolayers are promising materials due to their fascinating properties, such as ease of preparation, ability to intercalate different type of anions (inorganic, organic, biomolecules, and even genes), high thermal stability, delivery of intercalated anions in a sustained manner, high biocompatibility, and easy biodegradation. Inorganic nanolayers have been the focus for researchers over the last decade, resulting in widening application horizons, especially in the field of biomedical science. These nanolayers have been widely applied in drug and gene delivery. They have also been applied in biosensing technology, and most recently in bioimaging science. The suitability of inorganic nanolayers for application in drug delivery, gene delivery, biosensing technology, and bioimaging science makes them ideal materials to be applied for theranostic purposes. In this paper, we review the structure, methods of preparation, and latest advances made by inorganic nanolayers in such biomedical applications as drug delivery, gene delivery, biosensing, and bioimaging.

  5. Transfer characterization of sulfur from coal-burning emission to plant leaves by PIXE and XANES

    Energy Technology Data Exchange (ETDEWEB)

    Bao, L.M.; Zhang, G.L.; Zhang, Y.X.; Li, Y.; Lin, J.; Liu, W.; Cao, Q.C.; Zhao, Y.D.; Ma, C.Y.; Han, Y. [Chinese Academy of Sciences, Shanghai (China). Shanghai Institute of Applied Physics

    2009-11-15

    The impact of coal-burning emission on sulfur in camphor leaves was investigated using Proton Induced X-ray Emission (PIXE) and synchrotron radiation technique X-ray Absorption Near-Edge Structure (XANES) spectroscopy. The PIXE results show that the sulfur concentrations in the leaves collected at the polluted site are significantly higher than those in controls. The sulfur XANES spectra show the presence of organic (disulfides, thiols, thioethers, sulfonates and sulfoxides) and inorganic sulfur (sulfates) in the leaves. The inorganic sulfur in the leaves of camphor tree polluted by coal combustion is 15% more than that of the control site. The results suggest that the long-term coal-burning pollution resulted in an enhanced content of the total sulfur and sulfate in the leaves, and the uptake of sulfur by leaves had exceeded the metabolic requirement of plants and the excess of sulfur was stored as SO{sub 4}2{sup -}. It can monitor the sulfur pollution in atmosphere.

  6. Nanostructured sulfur cathodes

    KAUST Repository

    Yang, Yuan

    2013-01-01

    Rechargeable Li/S batteries have attracted significant attention lately due to their high specific energy and low cost. They are promising candidates for applications, including portable electronics, electric vehicles and grid-level energy storage. However, poor cycle life and low power capability are major technical obstacles. Various nanostructured sulfur cathodes have been developed to address these issues, as they provide greater resistance to pulverization, faster reaction kinetics and better trapping of soluble polysulfides. In this review, recent developments on nanostructured sulfur cathodes and mechanisms behind their operation are presented and discussed. Moreover, progress on novel characterization of sulfur cathodes is also summarized, as it has deepened the understanding of sulfur cathodes and will guide further rational design of sulfur electrodes. © 2013 The Royal Society of Chemistry.

  7. Dissimilatory oxidation and reduction of elemental sulfur in thermophilic archaea.

    Science.gov (United States)

    Kletzin, Arnulf; Urich, Tim; Müller, Fabian; Bandeiras, Tiago M; Gomes, Cláudio M

    2004-02-01

    The oxidation and reduction of elemental sulfur and reduced inorganic sulfur species are some of the most important energy-yielding reactions for microorganisms living in volcanic hot springs, solfataras, and submarine hydrothermal vents, including both heterotrophic, mixotrophic, and chemolithoautotrophic, carbon dioxide-fixing species. Elemental sulfur is the electron donor in aerobic archaea like Acidianus and Sulfolobus. It is oxidized via sulfite and thiosulfate in a pathway involving both soluble and membrane-bound enzymes. This pathway was recently found to be coupled to the aerobic respiratory chain, eliciting a link between sulfur oxidation and oxygen reduction at the level of the respiratory heme copper oxidase. In contrast, elemental sulfur is the electron acceptor in a short electron transport chain consisting of a membrane-bound hydrogenase and a sulfur reductase in (facultatively) anaerobic chemolithotrophic archaea Acidianus and Pyrodictium species. It is also the electron acceptor in organoheterotrophic anaerobic species like Pyrococcus and Thermococcus, however, an electron transport chain has not been described as yet. The current knowledge on the composition and properties of the aerobic and anaerobic pathways of dissimilatory elemental sulfur metabolism in thermophilic archaea is summarized in this contribution.

  8. Transnitrosation of alicyclic N-nitrosamines containing a sulfur atom.

    Science.gov (United States)

    Inami, Keiko; Kondo, Sonoe; Ono, Yuta; Saso, Chiharu; Mochizuki, Masataka

    2013-12-15

    Aromatic and aliphatic nitrosamines are known to transfer a nitrosonium ion to another amine. The transnitrosation of alicyclic N-nitroso compounds generates S-nitrosothiols, which are potential nitric oxide donors in vivo. In this study, certain alicyclic N-nitroso compounds based on non-mutagenic N-nitrosoproline or N-nitrosothioproline were synthesised, and the formation of S-nitrosoglutathione (GSNO) was quantified under acidic conditions. We then investigated the effect of a sulfur atom as the substituent and as a ring component on the GSNO formation. In the presence of thiourea under acidic conditions, GSNO was formed from N-nitrosoproline and glutathione, and an N-nitroso compound containing a sulfur atom and glutathione produced GSNO without thiourea. The quantity of GSNO derived from the reaction of the N-nitrosamines containing a sulfur atom and glutathione was higher than that from the N-nitrosoproline and glutathione plus thiourea. Among the analogues that contained a sulfur atom either in the ring or as a substituent, the thiazolidines produced a slightly higher quantity of GSNO than the analogue with a thioamide group. A compound containing sulfur atoms both in the ring and as a substituent exhibited the highest activity for GSNO formation among the alicyclic N-nitrosamines tested. The results indicate that the intramolecular sulfur atom plays an important role in the transnitrosation via alicyclic N-nitroso compounds to form GSNO. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  9. Laying Waste to Mercury: Inexpensive Sorbents Made from Sulfur and Recycled Cooking Oils

    Science.gov (United States)

    Worthington, Max J. H.; Kucera, Renata L.; Albuquerque, Inês S.; Gibson, Christopher T.; Sibley, Alexander; Slattery, Ashley D.; Campbell, Jonathan A.; Alboaiji, Salah F. K.; Muller, Katherine A.; Young, Jason; Adamson, Nick; Gascooke, Jason R.; Jampaiah, Deshetti; Sabri, Ylias M.; Bhargava, Suresh K.; Ippolito, Samuel J.; Lewis, David A.; Quinton, Jamie S.; Ellis, Amanda V.; Johs, Alexander; Bernardes, Gonçalo J. L.

    2017-01-01

    Abstract Mercury pollution threatens the environment and human health across the globe. This neurotoxic substance is encountered in artisanal gold mining, coal combustion, oil and gas refining, waste incineration, chloralkali plant operation, metallurgy, and areas of agriculture in which mercury‐rich fungicides are used. Thousands of tonnes of mercury are emitted annually through these activities. With the Minamata Convention on Mercury entering force this year, increasing regulation of mercury pollution is imminent. It is therefore critical to provide inexpensive and scalable mercury sorbents. The research herein addresses this need by introducing low‐cost mercury sorbents made solely from sulfur and unsaturated cooking oils. A porous version of the polymer was prepared by simply synthesising the polymer in the presence of a sodium chloride porogen. The resulting material is a rubber that captures liquid mercury metal, mercury vapour, inorganic mercury bound to organic matter, and highly toxic alkylmercury compounds. Mercury removal from air, water and soil was demonstrated. Because sulfur is a by‐product of petroleum refining and spent cooking oils from the food industry are suitable starting materials, these mercury‐capturing polymers can be synthesised entirely from waste and supplied on multi‐kilogram scales. This study is therefore an advance in waste valorisation and environmental chemistry. PMID:28763123

  10. Laying Waste to Mercury: Inexpensive Sorbents Made from Sulfur and Recycled Cooking Oils.

    Science.gov (United States)

    Worthington, Max J H; Kucera, Renata L; Albuquerque, Inês S; Gibson, Christopher T; Sibley, Alexander; Slattery, Ashley D; Campbell, Jonathan A; Alboaiji, Salah F K; Muller, Katherine A; Young, Jason; Adamson, Nick; Gascooke, Jason R; Jampaiah, Deshetti; Sabri, Ylias M; Bhargava, Suresh K; Ippolito, Samuel J; Lewis, David A; Quinton, Jamie S; Ellis, Amanda V; Johs, Alexander; Bernardes, Gonçalo J L; Chalker, Justin M

    2017-11-16

    Mercury pollution threatens the environment and human health across the globe. This neurotoxic substance is encountered in artisanal gold mining, coal combustion, oil and gas refining, waste incineration, chloralkali plant operation, metallurgy, and areas of agriculture in which mercury-rich fungicides are used. Thousands of tonnes of mercury are emitted annually through these activities. With the Minamata Convention on Mercury entering force this year, increasing regulation of mercury pollution is imminent. It is therefore critical to provide inexpensive and scalable mercury sorbents. The research herein addresses this need by introducing low-cost mercury sorbents made solely from sulfur and unsaturated cooking oils. A porous version of the polymer was prepared by simply synthesising the polymer in the presence of a sodium chloride porogen. The resulting material is a rubber that captures liquid mercury metal, mercury vapour, inorganic mercury bound to organic matter, and highly toxic alkylmercury compounds. Mercury removal from air, water and soil was demonstrated. Because sulfur is a by-product of petroleum refining and spent cooking oils from the food industry are suitable starting materials, these mercury-capturing polymers can be synthesised entirely from waste and supplied on multi-kilogram scales. This study is therefore an advance in waste valorisation and environmental chemistry. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  11. Separation of fission products using inorganic exchangers

    International Nuclear Information System (INIS)

    Murthy, T.S.; Balasubramanian, K.R.; Rao, K.L.N.; Venkatachalam, R.; Varma, R.N.

    1981-01-01

    This paper describes the separation of long lived fission products like caesium-137, strontium-90 using inorganic exchangers ammonium phosphomolybdate and zirconium antimonate. A revised flow sheet is proposed for the sequential separation of these isotopes using the above two compounds. This is a modification of the earlier scheme developed which involved the use of four inorganic exchangers namely ammonium phosphomolybdate, manganese dioxide, zirconium antimonate and polyantimonic acid. The elution of the adsorbed elements like cerium, strontium, and sodium has been studied and it has been possible to elute these using different eluting agents. (author)

  12. Identification of control parameters for the sulfur gas storability with bag sampling methods

    Science.gov (United States)

    Air samples containing sulfur compounds are often collected and stored in sample bags prior to analyses. The storage stability of six gaseous sulfur compounds (H2S, CH3SH, DMS, CS2, DMDS and SO2) was compared between two different bag materials (polyvinyl fluoride (PVF) and polyester aluminum (PEA))...

  13. Use of stirred tanks for studying matrix effects caused by inorganic acids, easily ionized elements and organic solvents in inductively coupled plasma atomic emission spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Paredes, Eduardo [Departamento de Quimica Analitica, Nutricion y Bromatologia, University of Alicante, 03080 Alicante (Spain); Maestre, Salvador E. [Departamento de Quimica Analitica, Nutricion y Bromatologia, University of Alicante, 03080 Alicante (Spain); Todoli, Jose L. [Departamento de Quimica Analitica, Nutricion y Bromatologia, University of Alicante, 03080 Alicante (Spain)]. E-mail: jose.todoli@ua.es

    2006-03-15

    A stirred tank was used for the first time to elucidate the mechanism responsible for inductively coupled plasma atomic emission spectroscopy (ICP-AES) matrix effects caused by inorganic, acids and easily ionized elements (EIEs), as well as organic, ethanol and acetic acid, compounds. In order to gradually increase the matrix concentration, a matrix solution was introduced inside a stirred container (tank) initially filled with an aqueous multielement standard. PolyTetraFluoroEthylene (PTFE) tubing was used to deliver the resulting solution to the liquid sample introduction system. Matrix concentration ranged from 0 to 2 mol l{sup -1} in the case of inorganic acids (i.e., nitric, sulfuric, hydrochloric and a mixture of them), from 0 to about 2500 mg l{sup -1} for EIEs (i.e., sodium, calcium and mixtures of both) and from 0% to 15%, w/w for organic compounds. Up to 40-50 different solutions were prepared and measured in a period of time shorter than 6-7 min. This investigation was carried out in terms of emission intensity and tertiary aerosols characteristics. The experimental setup used in the present work allowed to thoroughly study the effect of matrix concentration on analytical signal. Generally speaking, the experiments concerning tertiary aerosol characterization revealed that, in the case of inorganic acids and EIEs, the mechanism responsible for changes in aerosol characteristics was the droplet fission. In contrast, for organic matrices it was found that the interference was caused by a change in both aerosol transport and plasma thermal characteristics. The extent of the interferences caused by organic as well as inorganic compounds was compared for a set of 14 emission lines through a wide range of matrix concentrations. With a stirred tank, it is possible to choose an efficient internal standard for any given matrix composition. The time required to complete this procedure was shorter than 7 min.

  14. Use of stirred tanks for studying matrix effects caused by inorganic acids, easily ionized elements and organic solvents in inductively coupled plasma atomic emission spectrometry

    International Nuclear Information System (INIS)

    Paredes, Eduardo; Maestre, Salvador E.; Todoli, Jose L.

    2006-01-01

    A stirred tank was used for the first time to elucidate the mechanism responsible for inductively coupled plasma atomic emission spectroscopy (ICP-AES) matrix effects caused by inorganic, acids and easily ionized elements (EIEs), as well as organic, ethanol and acetic acid, compounds. In order to gradually increase the matrix concentration, a matrix solution was introduced inside a stirred container (tank) initially filled with an aqueous multielement standard. PolyTetraFluoroEthylene (PTFE) tubing was used to deliver the resulting solution to the liquid sample introduction system. Matrix concentration ranged from 0 to 2 mol l -1 in the case of inorganic acids (i.e., nitric, sulfuric, hydrochloric and a mixture of them), from 0 to about 2500 mg l -1 for EIEs (i.e., sodium, calcium and mixtures of both) and from 0% to 15%, w/w for organic compounds. Up to 40-50 different solutions were prepared and measured in a period of time shorter than 6-7 min. This investigation was carried out in terms of emission intensity and tertiary aerosols characteristics. The experimental setup used in the present work allowed to thoroughly study the effect of matrix concentration on analytical signal. Generally speaking, the experiments concerning tertiary aerosol characterization revealed that, in the case of inorganic acids and EIEs, the mechanism responsible for changes in aerosol characteristics was the droplet fission. In contrast, for organic matrices it was found that the interference was caused by a change in both aerosol transport and plasma thermal characteristics. The extent of the interferences caused by organic as well as inorganic compounds was compared for a set of 14 emission lines through a wide range of matrix concentrations. With a stirred tank, it is possible to choose an efficient internal standard for any given matrix composition. The time required to complete this procedure was shorter than 7 min

  15. Tropospheric chemistry of natural hydrocarbons, aldehydes, and peroxy radicals: Their connections to sulfuric acid production and climate effects

    International Nuclear Information System (INIS)

    Gaffney, J.S.; Marley, N.A.

    1993-05-01

    Recent work has shown that natural hydrocarbon emissions can significantly affect the levels of urban and regional tropospheric ozone. We report on the reactivities of these biogenic trace gases, particularly isoprene, focusing on their importance in the production of aldehydes and peroxy radicals, leading to increased levels of hydrogen over regional forests. Hydrogen peroxide can lead to the wet oxidation of sulfur dioxide to acidic sulfate in aerosols, fogs, and clouds. In turn, acidic sulfate can act to as a light scattering aerosol and a source of cloud condensation nuclei (CCN), potentially leading to global cooling. Aerosol sulfate and other dissolved organic and inorganic compounds can also play important roles as a greenhouse species in the lower troposphere

  16. Layered inorganic solids

    Czech Academy of Sciences Publication Activity Database

    Čejka, Jiří; Morris, R. E.; Nachtigall, P.; Roth, Wieslaw Jerzy

    2014-01-01

    Roč. 43, č. 27 (2014), s. 10274-10275 ISSN 1477-9226 Institutional support: RVO:61388955 Keywords : layered inorganic solids * physical chemistry * catalysis Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 4.197, year: 2014

  17. Inorganic Coatings Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The inorganic Coatings Lab provides expertise to Navy and Joint Service platforms acquisition IPTs to aid in materials and processing choices which balance up-front...

  18. Inorganic and geological materials

    International Nuclear Information System (INIS)

    Dinnin, J.I.

    1975-01-01

    Recently described methods for applied inorganic analysis are reviewed from an interdisciplinary standpoint. Abstracts and periodical literature up to Nov. 1974, are included for consideration. The following areas of interest are covered: general reviews of inorganic analytical techniques; analytical techniques, areas of application, and analysis of individual elements. Selected books, monographs, and review articles on the analytical chemistry of the elements are listed. (416 references.) (U.S.)

  19. Sulfur and selenium isotope separation by distillation

    International Nuclear Information System (INIS)

    Mills, T. R.; McInteer, B. B.; Montoya, J. G.

    1988-01-01

    Sulfur and selenium isotopes are used for labeled compounds and as precursors for radioisotope production; however, both limited availability and high costs are problems. A new method is needed for large-scale separation of these isotopes. Experimental distillation columns were used to measure isotopic separations for sulfur and selenium compounds. The maximum total isotope separation of 32 S vs. 34 S were 1.127 for H 2 S, 1.048 for COS, 0.838 for SF 4 , and 1.058 for CH 3 SH. Relative volatilities of 32 S vs. 34 S are 1.0006 for COS and 0.9976 for SF 4 . There is a reverse isotope effect for carbon in COS. No isotopic separation was observed for dimethyl selenide. The lower mass selenium isotopes in H 2 Se are more volatile. Distillation is a promising method for separating sulfur isotopes on a production scale. Existing distillation technology produced separated isotopes with an effect similar to that found for sulfur in SF 4 . 8 refs., 2 tabs

  20. Sulfur and selenium isotope separation by distillation

    International Nuclear Information System (INIS)

    Mills, T.R.; McInteer, B.B.; Montoya, J.G.

    1989-01-01

    Sulfur and selenium isotopes are used for labeled compounds and as precursors for radioisotope production; however, both limited availability and high costs are problems. A new method is needed for large-scale separation of theses isotopes. Experimental distillation columns were used to measure isotopic separations for sulfur and selenium compounds. The maximum total isotope separations of 32 S vs. 34 S were 1.127 for H 2 S, 1.048 for COS, 0.838 for SF 4 , and 1.058 for CH 3 SH. Relative volatilities of 32 S and 34 S are 1.0006 for COS and 0.9976 for SF 4 . There is a reverse isotope effect for carbon in COS. No isotopic separation was observed for dimethyl selenide. The lower mass selenium isotopes in H 2 Se are more volatile. Distillation is a promising method for separating sulfur isotopes on a production scale. Existing distillation technology produces separated isotopes with an effect similar to that found for sulfur in SF 4 . (author). 8 refs.; 2 tabs

  1. Evaluation of haloalkaliphilic sulfur-oxidizing microorganisms with potential application in the effluent treatment of the petroleum industry.

    Science.gov (United States)

    Olguín-Lora, P; Le Borgne, S; Castorena-Cortés, G; Roldán-Carrillo, T; Zapata-Peñasco, I; Reyes-Avila, J; Alcántara-Pérez, S

    2011-02-01

    Haloalkaliphilic sulfur-oxidizing mixed cultures for the treatment of alkaline-saline effluents containing sulfide were characterized and evaluated. The mixed cultures (IMP-PB, IMP-XO and IMP-TL) were obtained from Mexican alkaline soils collected in Puebla (PB), Xochimilco (XO) and Tlahuac (TL), respectively. The Ribosomal Intergenic Spacer Analysis (RISA) revealed bacteria related to Thioalkalibacterium and Thioalkalivibrio in IMP-XO and IMP-PB mixed cultures. Halomonas strains were detected in IMP-XO and IMP-TL. In addition, an uncultured Bacteroides bacterium was present in IMP-TL. Mixed cultures were evaluated at different pH and NaCl concentrations at 30°C. IMP-PB and IMP-TL expressed thiosulfate-oxidizing activity in the 7.5-10.5 pH range, whereas IMP-XO presented its maximal activity with 19.0 mg O₂ g (protein)⁻¹ min⁻¹, at pH 10.6; it was not affected by NaCl concentrations up to 1.7 M. In continuous culture, IMP-XO showed a growth rate of 15 day⁻¹, productivity of 433.4 mg(protein) l⁻¹ day⁻¹ and haloalkaliphilic sulfur-oxidizing activity was also detected up to 170 mM by means of N-methyl-diethanolamine (MDEA). Saline-alkaline soil samples are potential sources of haloalkaliphilic sulfur-oxidizing bacteria and the mixed cultures could be applied in the treatment of inorganic sulfur compounds in petroleum industry effluents under alkaline-saline conditions.

  2. Influence of sulfur and nitrogen supply on the susceptibility of Pisum sativum to SO/sub 2/

    Energy Technology Data Exchange (ETDEWEB)

    Klein, H; Jaeger, H J; Steubing, L

    1974-01-01

    The susceptibility of Pisum to SO/sub 2/ injury was examined in relation to the sulfur and nitrogen nutrition. The injury was measured by comparing the dry matter yield to control and treated plants. SO/sub 2/ effects on metabolism were established by determining the content of organic and inorganic sulfur and, indirectly, by measuring total nitrogen, amino acid nitrogen, and protein nitrogen. The plants grown in nutrient solutions deficient in sulfur or nitrogen showed a decreased sensitivity to SO/sub 2/ pollution compared to the control. The higher content of amino acid nitrogen and organic sulfur of the plants grown in a nitrogen-deficient solution suggests that an increased synthesis of sulfur containing amino acids occurs. The slighter injury of the plants deficient in sulfur may be explained by the delayed sulfur supply.

  3. The production of sulfur targets for gamma-ray spectroscopy

    CERN Document Server

    Greene, J P

    2002-01-01

    The production of thin sulfur targets for nuclear physics, either in elemental or in compound form, is problematic, due to low melting points, high vapor pressures and high dissociation rates. Many sulfur compounds have been tried in the past without great success. In this paper, we report the use of spray coating molybdenum disulfide onto a thin carbon backing. The targets were of thickness 750 mu g/cm sup 2 (approx 300 mu g/cm sup 2 of sulfur) on 15 mu g/cm sup 2 carbon backings, and withstood 4 pnA (approx 10 mW/cm sup 2) of deposited beam power for several days without apparent loss of sulfur content.

  4. Sulfide intrusion in seagrasses assessed by stable sulfur isotopes—a synthesis of current results

    DEFF Research Database (Denmark)

    Holmer, Marianne; Hasler-Sheetal, Harald

    2014-01-01

    of sedimentary sulfide in the plant increases, and accumulation of elemental sulfur (S0) inside the plant with δ34S values similar to the sedimentary sulfide suggests that S0 is an important reoxidation product of the sedimentary sulfide. The accumulation of S0 can, however, not account for the increase...... in sulfur in the tissue, and other sulfur containing compounds such as thiols, organic sulfur, and sulfate contribute to the accumulated sulfur pool. Experimental studies with seagrasses exposed to environmental and biological stressors show decreasing δ34S in the tissues along with reduction in growth...

  5. Morphological study of silver corrosion in highly aggressive sulfur environments

    DEFF Research Database (Denmark)

    Minzari, Daniel; Jellesen, Morten Stendahl; Møller, Per

    2011-01-01

    A silicone coated power module, having silver conducting lines, showed severe corrosion, after prolonged use as part of an electronic device in a pig farm environment, where sulfur containing corrosive gasses are known to exist in high amounts. Permeation of sulfur gasses and humidity through...... the silicone coating to the interface has resulted in three corrosion types namely: uniform corrosion, conductive anodic filament type of Ag2S growth, and silver migration with subsequent formation of sulfur compounds. Detailed morphological investigation of new and corroded power modules was carried out...

  6. Sulfur and Hydrogen Isotope Anomalies in Meteorite Sulfonic Acids

    Science.gov (United States)

    Cooper, George W.; Thiemens, Mark H.; Jackson, Teresa L.; Chang, Sherwood

    1997-01-01

    Intramolecular carbon, hydrogen, and sulfur isotope ratios were measured on a homologous series of organic sulfonic acids discovered in the Murchison meteorite. Mass-independent sulfur isotope fractionations were observed along with high deuterium/hydrogen ratios. The deuterium enrichments indicate formation of the hydrocarbon portion of these compounds in a low-temperature environment that is consistent with that of interstellar clouds. Sulfur-33 enrichments observed in methanesulfonic acid could have resulted from gas-phase ultraviolet irradiation of a precursor, carbon disulfide. The source of the sulfonic acid precursors may have been the reactive interstellar molecule carbon monosulfide.

  7. Inorganic UV filters

    Directory of Open Access Journals (Sweden)

    Eloísa Berbel Manaia

    2013-06-01

    Full Text Available Nowadays, concern over skin cancer has been growing more and more, especially in tropical countries where the incidence of UVA/B radiation is higher. The correct use of sunscreen is the most efficient way to prevent the development of this disease. The ingredients of sunscreen can be organic and/or inorganic sun filters. Inorganic filters present some advantages over organic filters, such as photostability, non-irritability and broad spectrum protection. Nevertheless, inorganic filters have a whitening effect in sunscreen formulations owing to the high refractive index, decreasing their esthetic appeal. Many techniques have been developed to overcome this problem and among them, the use of nanotechnology stands out. The estimated amount of nanomaterial in use must increase from 2000 tons in 2004 to a projected 58000 tons in 2020. In this context, this article aims to analyze critically both the different features of the production of inorganic filters (synthesis routes proposed in recent years and the permeability, the safety and other characteristics of the new generation of inorganic filters.

  8. The uptake and excretion of partially oxidized sulfur expands the repertoire of energy resources metabolized by hydrothermal vent symbioses.

    Science.gov (United States)

    Beinart, R A; Gartman, A; Sanders, J G; Luther, G W; Girguis, P R

    2015-05-07

    Symbiotic associations between animals and chemoautotrophic bacteria crowd around hydrothermal vents. In these associations, symbiotic bacteria use chemical reductants from venting fluid for the energy to support autotrophy, providing primary nutrition for the host. At vents along the Eastern Lau Spreading Center, the partially oxidized sulfur compounds (POSCs) thiosulfate and polysulfide have been detected in and around animal communities but away from venting fluid. The use of POSCs for autotrophy, as an alternative to the chemical substrates in venting fluid, could mitigate competition in these communities. To determine whether ESLC symbioses could use thiosulfate to support carbon fixation or produce POSCs during sulfide oxidation, we used high-pressure, flow-through incubations to assess the productivity of three symbiotic mollusc genera-the snails Alviniconcha spp. and Ifremeria nautilei, and the mussel Bathymodiolus brevior-when oxidizing sulfide and thiosulfate. Via the incorporation of isotopically labelled inorganic carbon, we found that the symbionts of all three genera supported autotrophy while oxidizing both sulfide and thiosulfate, though at different rates. Additionally, by concurrently measuring their effect on sulfur compounds in the aquaria with voltammetric microelectrodes, we showed that these symbioses excreted POSCs under highly sulfidic conditions, illustrating that these symbioses could represent a source for POSCs in their habitat. Furthermore, we revealed spatial disparity in the rates of carbon fixation among the animals in our incubations, which might have implications for the variability of productivity in situ. Together, these results re-shape our thinking about sulfur cycling and productivity by vent symbioses, demonstrating that thiosulfate may be an ecologically important energy source for vent symbioses and that they also likely impact the local geochemical regime through the excretion of POSCs.

  9. Biogenic, urban, and wildfire influences on the molecular composition of dissolved organic compounds in cloud water

    Science.gov (United States)

    Cook, Ryan D.; Lin, Ying-Hsuan; Peng, Zhuoyu; Boone, Eric; Chu, Rosalie K.; Dukett, James E.; Gunsch, Matthew J.; Zhang, Wuliang; Tolic, Nikola; Laskin, Alexander; Pratt, Kerri A.

    2017-12-01

    Organic aerosol formation and transformation occurs within aqueous aerosol and cloud droplets, yet little is known about the composition of high molecular weight organic compounds in cloud water. Cloud water samples collected at Whiteface Mountain, New York, during August-September 2014 were analyzed by ultra-high-resolution mass spectrometry to investigate the molecular composition of dissolved organic carbon, with a focus on sulfur- and nitrogen-containing compounds. Organic molecular composition was evaluated in the context of cloud water inorganic ion concentrations, pH, and total organic carbon concentrations to gain insights into the sources and aqueous-phase processes of the observed high molecular weight organic compounds. Cloud water acidity was positively correlated with the average oxygen : carbon ratio of the organic constituents, suggesting the possibility for aqueous acid-catalyzed (prior to cloud droplet activation or during/after cloud droplet evaporation) and/or radical (within cloud droplets) oxidation processes. Many tracer compounds recently identified in laboratory studies of bulk aqueous-phase reactions were identified in the cloud water. Organosulfate compounds, with both biogenic and anthropogenic volatile organic compound precursors, were detected for cloud water samples influenced by air masses that had traveled over forested and populated areas. Oxidation products of long-chain (C10-12) alkane precursors were detected during urban influence. Influence of Canadian wildfires resulted in increased numbers of identified sulfur-containing compounds and oligomeric species, including those formed through aqueous-phase reactions involving methylglyoxal. Light-absorbing aqueous-phase products of syringol and guaiacol oxidation were observed in the wildfire-influenced samples, and dinitroaromatic compounds were observed in all cloud water samples (wildfire, biogenic, and urban-influenced). Overall, the cloud water molecular composition depended on

  10. Radiolysis of other organic compounds

    International Nuclear Information System (INIS)

    Pikaev, A.K.

    1986-01-01

    Peculiarities of radiolysis of organic halogen, phosphorus, sulfur and nitrogen (including amines, amides, nitriles et al.) compounds in liquid phase are discussed. Intermediate and stable finish products of radiolysis of the given compounds, properties and radiochemical yields of these products are considered

  11. Aircraft exhaust sulfur emissions

    Energy Technology Data Exchange (ETDEWEB)

    Brown, R C; Anderson, M R; Miake-Lye, R C; Kolb, C E [Aerodyne Research, Inc., Billerica, MA (United States). Center for Chemical and Environmental Physics; Sorokin, A A; Buriko, Y I [Scientific Research Center ` Ecolen` , Moscow (Russian Federation)

    1998-12-31

    The extent to which fuel sulfur is converted to SO{sub 3} during combustion and the subsequent turbine flow in supersonic and subsonic aircraft engines is estimated numerically. The analysis is based on: a flamelet model with non-equilibrium sulfur chemistry for the combustor, and a one-dimensional, two-stream model with finite rate chemical kinetics for the turbine. The results indicate that between 2% and 10% of the fuel sulfur is emitted as SO{sub 3}. It is also shown that, for a high fuel sulfur mass loading, conversion in the turbine is limited by the level of atomic oxygen at the combustor exit, leading to higher SO{sub 2} oxidation efficiency at lower fuel sulfur loadings. While SO{sub 2} and SO{sub 3} are the primary oxidation products, the model results further indicate H{sub 2}SO{sub 4} levels on the order of 0.1 ppm for supersonic expansions through a divergent nozzle. This source of fully oxidized S(6) (SO{sub 3} + H{sub 2}SO{sub 4}) exceeds previously calculated S(6) levels due to oxidation of SO{sub 2} by OH in the exhaust plume outside the engine nozzle. (author) 26 refs.

  12. Aircraft exhaust sulfur emissions

    Energy Technology Data Exchange (ETDEWEB)

    Brown, R.C.; Anderson, M.R.; Miake-Lye, R.C.; Kolb, C.E. [Aerodyne Research, Inc., Billerica, MA (United States). Center for Chemical and Environmental Physics; Sorokin, A.A.; Buriko, Y.I. [Scientific Research Center `Ecolen`, Moscow (Russian Federation)

    1997-12-31

    The extent to which fuel sulfur is converted to SO{sub 3} during combustion and the subsequent turbine flow in supersonic and subsonic aircraft engines is estimated numerically. The analysis is based on: a flamelet model with non-equilibrium sulfur chemistry for the combustor, and a one-dimensional, two-stream model with finite rate chemical kinetics for the turbine. The results indicate that between 2% and 10% of the fuel sulfur is emitted as SO{sub 3}. It is also shown that, for a high fuel sulfur mass loading, conversion in the turbine is limited by the level of atomic oxygen at the combustor exit, leading to higher SO{sub 2} oxidation efficiency at lower fuel sulfur loadings. While SO{sub 2} and SO{sub 3} are the primary oxidation products, the model results further indicate H{sub 2}SO{sub 4} levels on the order of 0.1 ppm for supersonic expansions through a divergent nozzle. This source of fully oxidized S(6) (SO{sub 3} + H{sub 2}SO{sub 4}) exceeds previously calculated S(6) levels due to oxidation of SO{sub 2} by OH in the exhaust plume outside the engine nozzle. (author) 26 refs.

  13. Organic sulfur metabolisms in hydrothermal environments.

    Science.gov (United States)

    Rogers, Karyn L; Schulte, Mitchell D

    2012-07-01

    Sulfur is central to the metabolisms of many organisms that inhabit extreme environments. While biotic and abiotic cycling of organic sulfur compounds has been well documented in low-temperature anaerobic environments, cycling of organic sulfur in hydrothermal environments has received less attention. Recently published thermodynamic data have been used to estimate aqueous alkyl thiol and sulfide activities in deep-sea hydrothermal systems. Here we use geochemical mixing models to predict fluid compositions that result from mixing end-member hydrothermal fluid from the East Pacific Rise with bottom seawater. These fluid compositions are combined with estimates of methanethiol and dimethylsulfide activities to evaluate energy yields for potential organic sulfur-based metabolisms under hydrothermal conditions. Aerobic respiration has the highest energy yields (over -240 kJ/mol e⁻) at lower temperature; however, oxygen is unlikely to persist at high temperatures, restricting aerobic respiration to mesophilic communities. Nitrite reduction to N₂ has the highest energy yields at higher temperatures (greater than ∼40 °C). Nitrate and nitrite reduction to ammonium also yield significant energy (up to -70 kJ/mol e⁻). Much lower, but still feasible energy yields are calculated for sulfate reduction, disproportionation, and reduction with H₂. Organic compound family and the activity of methanethiol and dimethylsulfide were less important than metabolic strategy in determining overall energy yields. All metabolic strategies considered were exergonic within some portion of the mixing regime suggesting that organic sulfur-based metabolisms may be prevalent within deep-sea hydrothermal vent microbial communities. © 2012 Blackwell Publishing Ltd.

  14. their use as Accelerator in Curing Process of Rubber Compounds

    Directory of Open Access Journals (Sweden)

    S. taghvaee

    2007-06-01

    Full Text Available In some special cases, rubber compounds with high amounts of unsaturated elastomer are recommended with organic sulfur donors instead of mineral sulfurs. In this condition, activated sulfur is produced in situ and curingprocess is facilitated without accelerators. Organic sulfur donor compounds have low thermal stability and in the vulcanization temperature produce free and activated sulfurs. The advantages of these compounds are:1. High effectiveness of curing agent in low quantities in rubber compounds manufacturing.2. Producing activated sulfurs in controlled condition and avoiding the over curing of rubber compounds.In this report the novel synthesis of some derivatives of diamino-disulfides which can be applied as sulfur donors in vulcanization of special rubber compounds is introduced. The key process is reaction of sulfurmonochloride with amines in petroleum ether as solvent in low temperature. Dithio-dimorpholine(DTDM, dithio-dipipyridyl (DTDP, dithio-bis dibutylamine (DTBDB and dithio-bisdiisopropyl amine (DTBDI were prepared according to this method. All products thus obtained were characterized by 1H and 13C-NMR spectroscopies. The effects of accelerating and sulfur donoring of all prepared agents were detected in rubber compounds with natural and synthetic rubber bases. All physical, chemical, reological and mechanical properties of rubber compounds based on prepared sulfur donors were characterized.

  15. Thorium inorganic gels

    International Nuclear Information System (INIS)

    Genet, M.; Brandel, V.

    1988-01-01

    The optimum pH and concentration values of thorium salts and oxoacids or oxoacid salts which lead to transparent and stable inorganic gels have been determined. The isotherm drying process of the gel at 50 0 C leads successively to a partly dehydrated gel, then, to the formation of an unusual liquid phase and, finally to a dry amorphous solid phase which is still transparent. This kind of transparent inorganic gels and amorphous phase can be used as matrices for spectroscopic studies [fr

  16. Sulfur activation in Hiroshima

    International Nuclear Information System (INIS)

    Kerr, G.D.; Pace, J.V. III.

    1987-01-01

    In 1979, we attempted to establish the validity of source terms for the Hiroshima and Nagasaki bombs using experimental data on sulfur activation. Close agreement was observed between measured and calculated values for test firings of Nagasaki-type bombs. The calculated values were based on source terms developed by W.E. Preeg at the Los Alamos National Laboratory (LANL). A discrepancy was found, however, when we compared calculated values for the two bombs because a 1956 report by R.R. Wilson stated that sulfur acitvation by fast neutrons in Hiroshima was approximately three times greater than in Nagasaki. Our calculations based on Preeg's source-term data predicted about equal sulfur activation in the two cities

  17. Inorganic and organic radiation chemistry: state and problems

    International Nuclear Information System (INIS)

    Kalyazin, E.P.; Bugaenko, L.T.

    1990-01-01

    Radiation inorganic and organic chemistry is presented on the basis of the general scheme and classification of radiolysis products and elementary processes, by which evolution of radiation-affected substances up to the final radiolysis products takes place. The evolution is traced for the representatives of inorganic and organic compounds. The contribution of radiation inorganic and organic chemistry to radiation technology, radiation materials technology, radiation ecology and medicine, is shown. Tendencies in the development of radiation chemistry and prediction of its certain directions are considered

  18. Heterogeneous Catalysis of Polyoxometalate Based Organic–Inorganic Hybrids

    Directory of Open Access Journals (Sweden)

    Yuanhang Ren

    2015-03-01

    Full Text Available Organic–inorganic hybrid polyoxometalate (POM compounds are a subset of materials with unique structures and physical/chemical properties. The combination of metal-organic coordination complexes with classical POMs not only provides a powerful way to gain multifarious new compounds but also affords a new method to modify and functionalize POMs. In parallel with the many reports on the synthesis and structure of new hybrid POM compounds, the application of these compounds for heterogeneous catalysis has also attracted considerable attention. The hybrid POM compounds show noteworthy catalytic performance in acid, oxidation, and even in asymmetric catalytic reactions. This review summarizes the design and synthesis of organic–inorganic hybrid POM compounds and particularly highlights their recent progress in heterogeneous catalysis.

  19. Isotope effects of sulfur in chemical reactions

    International Nuclear Information System (INIS)

    Mikolajczuk, A.

    1999-01-01

    Sulfur is an important component of organic matter because it forms compounds with many elements. Due to high chemical activity of sulfur, it takes part in biological and geological processes in which isotope effects are occurring. It has been shown during last years research of isotope effects that we have take into account not only mass difference but also many other physical properties of nuclides e.g. even or odd number of neutrons in nuclei, shape and distribution of charge, turn of nuclear spin etc. The factor remains that new theoretical ideas have been formed on the base of data, being obtained in fractionation processes of heavy element isotope, particularly uranium. Now it is being well known that effects unconnected with vibration energy have also caused an effect on fractionation of considerably lighter elements like iron and magnesium. The important question is, if these effects would come to light during the separation of sulfur isotopes. Sulfur have three even isotopes M = (32, 34, 36) and one odd M 33). This problem is still open. (author)

  20. Accidents with sulfuric acid

    Directory of Open Access Journals (Sweden)

    Rajković Miloš B.

    2006-01-01

    Full Text Available Sulfuric acid is an important industrial and strategic raw material, the production of which is developing on all continents, in many factories in the world and with an annual production of over 160 million tons. On the other hand, the production, transport and usage are very dangerous and demand measures of precaution because the consequences could be catastrophic, and not only at the local level where the accident would happen. Accidents that have been publicly recorded during the last eighteen years (from 1988 till the beginning of 2006 are analyzed in this paper. It is very alarming data that, according to all the recorded accidents, over 1.6 million tons of sulfuric acid were exuded. Although water transport is the safest (only 16.38% of the total amount of accidents in that way 98.88% of the total amount of sulfuric acid was exuded into the environment. Human factor was the common factor in all the accidents, whether there was enough control of the production process, of reservoirs or transportation tanks or the transport was done by inadequate (old tanks, or the accidents arose from human factor (inadequate speed, lock of caution etc. The fact is that huge energy, sacrifice and courage were involved in the recovery from accidents where rescue teams and fire brigades showed great courage to prevent real environmental catastrophes and very often they lost their lives during the events. So, the phrase that sulfuric acid is a real "environmental bomb" has become clearer.

  1. Structure of amorphous sulfur

    CSIR Research Space (South Africa)

    Eichinger, BE

    2001-06-01

    Full Text Available The lambda-transition of elemental sulfur occurring at about 159°C has long been associated with the conversion of cyclic S8 rings (c-S8) to amorphous polymer (a-S) via a ring opening polymerization. It is demonstrated, with the use of both density...

  2. SULFUR POLYMER ENCAPSULATION

    International Nuclear Information System (INIS)

    KALB, P.

    2001-01-01

    Sulfur polymer cement (SPC) is a thermoplastic polymer consisting of 95 wt% elemental sulfur and 5 wt% organic modifiers to enhance long-term durability. SPC was originally developed by the U.S. Bureau of Mines as an alternative to hydraulic cement for construction applications. Previous attempts to use elemental sulfur as a construction material in the chemical industry failed due to premature degradation. These failures were caused by the internal stresses that result from changes in crystalline structure upon cooling of the material. By reacting elemental sulfur with organic polymers, the Bureau of Mines developed a product that successfully suppresses the solid phase transition and significantly improves the stability of the product. SPC, originally named modified sulfur cement, is produced from readily available, inexpensive waste sulfur derived from desulfurization of both flue gases and petroleum. The commercial production of SPC is licensed in the United States by Martin Resources (Odessa, Texas) and is marketed under the trade name Chement 2000. It is sold in granular form and is relatively inexpensive ((approx)$0.10 to 0.12/lb). Application of SPC for the treatment of radioactive, hazardous, and mixed wastes was initially developed and patented by Brookhaven National Laboratory (BNL) in the mid-1980s (Kalb and Colombo, 1985; Colombo et al., 1997). The process was subsequently investigated by the Commission of the European Communities (Van Dalen and Rijpkema, 1989), Idaho National Engineering Laboratory (Darnell, 1991), and Oak Ridge National Laboratory (Mattus and Mattus, 1994). SPC has been used primarily in microencapsulation applications but can also be used for macroencapsulation of waste. SPC microencapsulation has been demonstrated to be an effective treatment for a wide variety of wastes, including incinerator hearth and fly ash; aqueous concentrates such as sulfates, borates, and chlorides; blowdown solutions; soils; and sludges. It is not

  3. Determination of organic compounds in medicinal plants, commercialized in capsulated forms and 'in natura' by wavelength dispersive X-ray fluorescence spectrometry (WDXRF). Determination of quantitative inorganic profiles; Determinacao de componentes organicos em plantas medicinais, comercializadas em forma de po (capsulas) e 'in natura', utilizando a tecnica de fluorescencia de raios X por dispersao de comprimento de onda (WDXRF). Determinacao de perfis inorganicos quantitativos

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Manuel Octavio M; Sato, Ivone Mulako; Salvador, Vera Lucia R [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Centro de Quimica e Meio Ambiente

    2005-07-01

    X-ray fluorescence technique was used to determine major and trace elements for five Brazilian commercial medicinal plants. The bromobutane (Barbatimao), Ginkgo folium (Ginkgo biloba), Echinodorus macrophyllus (Chapeu de couro), Valeriana officinalis (Valeriana), Cordia salicifolia (Porangaba) samples were collected from three to six different commercial suppliers. The species were collected 'in natura' (leaves, flowers, barks and roots) and capsulated forms. The samples were grinded in liquid N{sub 2} atmosphere and double layer pressed pellet were prepared. The elements Na, Mg, P, S, Cl, K, Ca, Mn, Fe, Ni, Cu, Zn, Rb e Sr concentrations were determined by individual calibration curves. The precision and accuracy of method were evaluated by certified reference material, NIST 1547 - Peach Leaves and the Chauvenet, Cochrane, ANOVA and Z-score statistical tests were applied. Each specimen presented a distinct inorganic profile and a great variation in its composition was observed. The inorganic profile will contribute for the elaboration of a quality and security guide to assure the phytotherapics commercialization. Moreover, these profiles could be used as complementary data to active farmaco compounds profiles for specimen's ratification. (author)

  4. Sulfur transformation during rapid hydropyrolysis of coal under high pressure by using a continuous free fall pyrolyzer

    Energy Technology Data Exchange (ETDEWEB)

    W.-C. Xu; M. Kumagai

    2003-02-01

    The behavior of sulfur transformation during rapid hydropyrolysis of coal was investigated using a pressurized, continuous free fall pyrolyzer under the conditions of temperature ranging from 923 to 1123 K and hydrogen pressure up to 5 MPa. The yields of sulfur converted to gas, tar and char were determined, together with the analyses of sulfur form distributions in coals and chars. The results showed that the decomposition of inorganic sulfur species was affected only by the temperature, while the increases in temperature and hydrogen pressure obviously enhanced the removal of organic sulfur from coal. The extent of organic sulfur removal was proportional to the coal conversion, depending on coal type. A significant retention of gaseous sulfur products by the organic matrix of the char was observed during hydropyrolysis of a Chinese coal above 1023 K, even under the pressurized hydrogen atmosphere. The kinetic analysis indicates that the rate of organic sulfur removal from coal was 0.2th-order with respect to the hydrogen pressure, and the activation energy for total sulfur removal and organic sulfur removal is 17 26 and 13 55 kJ/mol, respectively. The low activation energies suggest that the transformation and removal of sulfur from coal might be controlled by the diffusion and/or thermodynamic equilibrium during hydropyrolysis under the pressurized conditions. 29 refs., 10 figs., 3 tabs.

  5. Human Exposure and Health Effects of Inorganic and Elemental Mercury

    Science.gov (United States)

    Zheng, Wei

    2012-01-01

    Mercury is a toxic and non-essential metal in the human body. Mercury is ubiquitously distributed in the environment, present in natural products, and exists extensively in items encountered in daily life. There are three forms of mercury, i.e., elemental (or metallic) mercury, inorganic mercury compounds, and organic mercury compounds. This review examines the toxicity of elemental mercury and inorganic mercury compounds. Inorganic mercury compounds are water soluble with a bioavailability of 7% to 15% after ingestion; they are also irritants and cause gastrointestinal symptoms. Upon entering the body, inorganic mercury compounds are accumulated mainly in the kidneys and produce kidney damage. In contrast, human exposure to elemental mercury is mainly by inhalation, followed by rapid absorption and distribution in all major organs. Elemental mercury from ingestion is poorly absorbed with a bioavailability of less than 0.01%. The primary target organs of elemental mercury are the brain and kidney. Elemental mercury is lipid soluble and can cross the blood-brain barrier, while inorganic mercury compounds are not lipid soluble, rendering them unable to cross the blood-brain barrier. Elemental mercury may also enter the brain from the nasal cavity through the olfactory pathway. The blood mercury is a useful biomarker after short-term and high-level exposure, whereas the urine mercury is the ideal biomarker for long-term exposure to both elemental and inorganic mercury, and also as a good indicator of body burden. This review discusses the common sources of mercury exposure, skin lightening products containing mercury and mercury release from dental amalgam filling, two issues that happen in daily life, bear significant public health importance, and yet undergo extensive debate on their safety. PMID:23230464

  6. Inorganic Constituents in Coal

    Directory of Open Access Journals (Sweden)

    Rađenović A.

    2006-02-01

    Full Text Available Coal contains not only organic matter but also small amounts of inorganic constituents. More thanone hundred different minerals and virtually every element in the periodic table have been foundin coal. Commonly found group minerals in coal are: major (quartz, pyrite, clays and carbonates,minor, and trace minerals. Coal includes a lot of elements of low mass fraction of the orderof w=0.01 or 0.001 %. They are trace elements connected with organic matter or minerals comprisedin coal. The fractions of trace elements usually decrease when the rank of coal increases.Fractions of the inorganic elements are different, depending on the coal bed and basin. A varietyof analytical methods and techniques can be used to determine the mass fractions, mode ofoccurrence, and distribution of organic constituents in coal. There are many different instrumentalmethods for analysis of coal and coal products but atomic absorption spectroscopy – AAS is theone most commonly used. Fraction and mode of occurrence are one of the main factors that haveinfluence on transformation and separation of inorganic constituents during coal conversion.Coal, as an important world energy source and component for non-fuels usage, will be continuouslyand widely used in the future due to its relatively abundant reserves. However, there is aconflict between the requirements for increased use of coal on the one hand and less pollution onthe other. It’s known that the environmental impacts, due to either coal mining or coal usage, canbe: air, water and land pollution. Although, minor components, inorganic constituents can exert asignificant influence on the economic value, utilization, and environmental impact of the coal.

  7. Inorganic Analytical Chemistry

    DEFF Research Database (Denmark)

    Berg, Rolf W.

    The book is a treatise on inorganic analytical reactions in aqueous solution. It covers about half of the elements in the periodic table, i.e. the most important ones : H, Li, B, C, N, O, Na, Mg, Al, P, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Sr, Mo, Ag, Cd, Sn, Sb, I, Ba, W,...

  8. Inorganic and organic trace mineral supplementation in weanling pig diets

    Directory of Open Access Journals (Sweden)

    MARIA C. THOMAZ

    2015-06-01

    Full Text Available A study was conducted to evaluate the effects of dietary inorganic and organic trace minerals in two levels of supplementation regarding performance, diarrhea occurrence, hematological parameters, fecal mineral excretion and mineral retention in metacarpals and liver of weanling pigs. Seventy piglets weaned at 21 days of age with an average initial body weight of 6.70 ± 0.38 kg were allotted in five treatments: control diet (no added trace mineral premix; 50% ITMP (control diet with inorganic trace mineral premix supplying only 50% of trace mineral requirements; 50% OTMP (control diet with organic trace mineral premix supplying only 50% of trace mineral requirements; 100% ITMP (control diet with inorganic trace mineral premix supplying 100% of trace mineral requirements; and 100% OTMP (control diet with organic trace mineral premix supplying 100% of trace mineral requirements. Feed intake and daily weight gain were not affected by treatments, however, piglets supplemented by trace minerals presented better gain:feed ratio. No differences were observed at calcium, phosphorus, potassium, magnesium, sodium and sulfur excreted in feces per kilogram of feed intake. Treatments did not affect calcium, phosphorus, magnesium, sulfur and iron content in metacarpals. Trace mineral supplementation, regardless of level and source, improved the performance of piglets.

  9. Radwaste issues belong in the inorganic classroom

    International Nuclear Information System (INIS)

    Williams, D.H.

    1991-01-01

    The safe isolation of high level radioactive wastes is a matter of significant importance. This material is derived primarily from spent nuclear fuel and defense weapon production. Every element on the periodic chart is represented. The majority are metallic elements. Over the thousands of years that they are to be isolated the primary chemistry will be oxidation. The mobility and fate of particular inner and outer transition element ions become very important. For that, one must understand their hydrolytic nature, their complexing tendencies and the solubilities of various compounds. This topic could easily serve as a centerpiece for an inorganic chemistry course. At the very least, it demands the attention of every teacher of inorganic chemistry and consideration by those whose research is directed to tangible problems. The discussion includes notes on the abundance and lifetimes of particular radioisotopes. The positive student responses to this approach are also shared

  10. Getting sulfur on target

    Energy Technology Data Exchange (ETDEWEB)

    Halbert, T.R.; Brignac, G.B. [ExxonMobil Process Research Labs. (United States); Greeley, J.P.; Demmin, R.A.; Roundtree, E.M. [ExxonMobil Research and Engineering Co. (United States)

    2000-06-01

    The paper focuses on how the required reductions in sulfur levels in motor vehicle fuel may be achieved over about the next five years. It is said that broadly there are two possible approaches, they are: (a) to hydrotreat the feed to the FCC unit and (b) to treat the naphtha produced by the FCC unit. The difficulties associated with these processes are mentioned. The article is presented under the sub-headings of (i) technology options for cat naphtha desulfurisation; (ii) optimising fractionator design via improved VLE models; (iii) commercial experience with ICN SCANfining; (iv) mercaptan predictive models and (v) process improvements. It was concluded that the individual needs of the refiner can be addressed by ExxonMobil Research and Engineering (EMRE) and the necessary reductions in sulfur levels can be achieved.

  11. Accidents with sulfuric acid

    OpenAIRE

    Rajković Miloš B.

    2006-01-01

    Sulfuric acid is an important industrial and strategic raw material, the production of which is developing on all continents, in many factories in the world and with an annual production of over 160 million tons. On the other hand, the production, transport and usage are very dangerous and demand measures of precaution because the consequences could be catastrophic, and not only at the local level where the accident would happen. Accidents that have been publicly recorded during the last eigh...

  12. Acidophilic sulfur disproportionation

    Science.gov (United States)

    Hardisty, Dalton S.; Olyphant, Greg A.; Bell, Jonathan B.; Johnson, Adam P.; Pratt, Lisa M.

    2013-07-01

    Bacterial disproportionation of elemental sulfur (S0) is a well-studied metabolism and is not previously reported to occur at pH values less than 4.5. In this study, a sediment core from an abandoned-coal-mine-waste deposit in Southwest Indiana revealed sulfur isotope fractionations between S0 and pyrite (Δ34Ses-py) of up to -35‰, inferred to indicate intense recycling of S0 via bacterial disproportionation and sulfide oxidation. Additionally, the chemistry of seasonally collected pore-water profiles were found to vary, with pore-water pH ranging from 2.2 to 3.8 and observed seasonal redox shifts expressed as abrupt transitions from Fe(III) to Fe(II) dominated conditions, often controlled by fluctuating water table depths. S0 is a common product during the oxidation of pyrite, a process known to generate acidic waters during weathering and production of acid mine drainage. The H2S product of S0 disproportionation, fractionated by up to -8.6‰, is rapidly oxidized to S0 near redox gradients via reaction with Fe(III) allowing for the accumulation of isotopically light S0 that can then become subject to further sulfur disproportionation. A mass-balance model for S0 incorporating pyrite oxidation, S0 disproportionation, and S0 oxidation readily explains the range of observed Δ34Ses-py and emphasizes the necessity of seasonally varying pyrite weathering and metabolic rates, as indicated by the pore water chemistry. The findings of this research suggest that S0 disproportionation is potentially a common microbial process at a pH < 4.5 and can create large sulfur isotope fractionations, even in the absence of sulfate reduction.

  13. Organic and inorganic decomposition products from the thermal desorption of atmospheric particles

    Science.gov (United States)

    Williams, Brent J.; Zhang, Yaping; Zuo, Xiaochen; Martinez, Raul E.; Walker, Michael J.; Kreisberg, Nathan M.; Goldstein, Allen H.; Docherty, Kenneth S.; Jimenez, Jose L.

    2016-04-01

    Atmospheric aerosol composition is often analyzed using thermal desorption techniques to evaporate samples and deliver organic or inorganic molecules to various designs of detectors for identification and quantification. The organic aerosol (OA) fraction is composed of thousands of individual compounds, some with nitrogen- and sulfur-containing functionality and, often contains oligomeric material, much of which may be susceptible to decomposition upon heating. Here we analyze thermal decomposition products as measured by a thermal desorption aerosol gas chromatograph (TAG) capable of separating thermal decomposition products from thermally stable molecules. The TAG impacts particles onto a collection and thermal desorption (CTD) cell, and upon completion of sample collection, heats and transfers the sample in a helium flow up to 310 °C. Desorbed molecules are refocused at the head of a gas chromatography column that is held at 45 °C and any volatile decomposition products pass directly through the column and into an electron impact quadrupole mass spectrometer. Analysis of the sample introduction (thermal decomposition) period reveals contributions of NO+ (m/z 30), NO2+ (m/z 46), SO+ (m/z 48), and SO2+ (m/z 64), derived from either inorganic or organic particle-phase nitrate and sulfate. CO2+ (m/z 44) makes up a major component of the decomposition signal, along with smaller contributions from other organic components that vary with the type of aerosol contributing to the signal (e.g., m/z 53, 82 observed here for isoprene-derived secondary OA). All of these ions are important for ambient aerosol analyzed with the aerosol mass spectrometer (AMS), suggesting similarity of the thermal desorption processes in both instruments. Ambient observations of these decomposition products compared to organic, nitrate, and sulfate mass concentrations measured by an AMS reveal good correlation, with improved correlations for OA when compared to the AMS oxygenated OA (OOA

  14. Inorganic nanolayers: structure, preparation, and biomedical applications

    Directory of Open Access Journals (Sweden)

    Saifullah B

    2015-09-01

    Full Text Available Bullo Saifullah, Mohd Zobir B HusseinMaterials Synthesis and Characterization Laboratory, Institute of Advanced Technology (ITMA, Universiti Putra Malaysia, Serdang, MalaysiaAbstract: Hydrotalcite-like compounds are two-dimensional inorganic nanolayers also known as clay minerals or anionic clays or layered double hydroxides/layered hydroxy salts, and have emerged as a single type of material with numerous biomedical applications, such as drug delivery, gene delivery, cosmetics, and biosensing. Inorganic nanolayers are promising materials due to their fascinating properties, such as ease of preparation, ability to intercalate different type of anions (inorganic, organic, biomolecules, and even genes, high thermal stability, delivery of intercalated anions in a sustained manner, high biocompatibility, and easy biodegradation. Inorganic nanolayers have been the focus for researchers over the last decade, resulting in widening application horizons, especially in the field of biomedical science. These nanolayers have been widely applied in drug and gene delivery. They have also been applied in biosensing technology, and most recently in bioimaging science. The suitability of inorganic nanolayers for application in drug delivery, gene delivery, biosensing technology, and bioimaging science makes them ideal materials to be applied for theranostic purposes. In this paper, we review the structure, methods of preparation, and latest advances made by inorganic nanolayers in such biomedical applications as drug delivery, gene delivery, biosensing, and bioimaging.Keywords: inorganic nanolayers, layered double hydroxides, layered hydroxy salts, drug delivery, biosensors, bioimaging

  15. Thermal dynamic analysis of sulfur removal from coal by electrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Li, D.; Gao, J.; Meng, F. [Qinghua University, Beijing (China). Dept. of Thermal Engineering

    2002-06-01

    The electrolytic reactions about sulfur removal from coal were studied by using chemical thermal dynamic analysis. According to the thermodynamical data, the Gibbs free energy value of the electrolytic reactions of pyritic and organic sulfur removal from coal is higher than zero. So, these electrolytic reactions are not spontaneous chemical reactions. In order to carry out desulfurisation by electrolysis, a certain voltage is necessary and important. Because theoretic decomposition voltage of pyrite and some parts of organic sulfur model compound is not very high, electrolysis reactions are easily to be carried out by using electrolysis technology. Mn ion and Fe ion are added into electrolysis solutions to accelerate the desulfurisation reaction. The electrolytic decomposition of coal is discussed. Because the theoretical decomposition voltage of some organic model compound is not high, the coal decomposition might happen. 17 refs., 4 tabs.

  16. Study of sulfur and vanadium in heavy petroleum products

    Energy Technology Data Exchange (ETDEWEB)

    Novelli, J.M.

    1982-10-01

    Sulfur compounds in heavy oil fractions (>450/sup 0/C) are studied in the first part of this work. After chemical oxidation by metachloroperbenzoic acid to obtain sulfones, sulfur compounds are analyzed by infrared spectroscopy for their qualitative and quantitative repartition. The method can be applied for the study of sulfur containing molecules before and after structural modifications of petroleum fractions by any chemical refining processes. In a second part vanadium is characterized in asphalt by physicochemical and chemical methods. 80% of the vanadium in a Boscan asphalt is under the form of porphyrins. Different associations are evidenced in petroleum fractions and metalloporphyrins, but the liaison between the vanadyl group and heterocondensate from asphalts is the more frequent.

  17. Enhanced corrosion resistance of carbon steel in normal sulfuric acid medium by some macrocyclic polyether compounds containing a 1,3,4-thiadiazole moiety: AC impedance and computational studies

    International Nuclear Information System (INIS)

    Bentiss, F.; Lebrini, M.; Vezin, H.; Chai, F.; Traisnel, M.; Lagrene, M.

    2009-01-01

    We report here the use of macrocyclic polyether compounds containing a 1,3,4-thiadiazole moiety (n-MCTH) in the corrosion inhibition of C38 carbon steel in 0.5 M H 2 SO 4 acid medium. The aim of this work is devoted to study the inhibition characteristics of these compounds for acid corrosion of C38 steel using electrochemical impedance spectroscopy (EIS). Data obtained from EIS show a frequency distribution and therefore a modeling element with frequency dispersion behaviour, a constant phase element (CPE) has been used. The experimental results obtained revealed that these compounds inhibited the steel corrosion in acid solution and the protection efficiency increased with increasing inhibitors concentration. The difference in their inhibitive action can be explained on the basis of the number of oxygen atoms present in the polyether ring which contribute to the chemisorption strength through the donor acceptor bond between the non bonding electron pair and the vacant orbital of metal surface. Adsorption of n-MCTH was found to follow the Langmuir's adsorption isotherm. The thermodynamic functions of adsorption process were calculated and the interpretation of the results is given. These results are complemented with quantum chemical study in order to provide an explanation of the differences between the probed inhibitors. Correlation between the inhibition efficiency and the structure of these compounds are presented.

  18. Occurrence and Turnover of Biogenic Sulfur in the Bering Sea During Summer

    Science.gov (United States)

    Li, Cheng-Xuan; Wang, Bao-Dong; Yang, Gui-Peng; Wang, Zi-Cheng; Chen, Jian-Fang; Lyu, Yang

    2017-11-01

    The horizontal/geographical variations in dissolved dimethylsulfide (DMS), its precursor dimethylsulfoniopropionate (DMSPd and DMSPp), and chlorophyll a (Chl a), as well as the oceanographic parameters influencing the concentrations of dimethylated sulfur compounds, were investigated in the Bering Sea from July to August 2012. Similar to Chl a, the surface DMS and DMSPp levels, as well as DMS(P) production and consumption rates, exhibited a declining gradient from the central basin to the continental shelf, with high-value areas appearing in the central basin, the slope regions, and Anadyr Strait but a low-value area occurring on the outer-middle continental shelf. Considerably high values of DMS and DMSP were measured in the saline Bering Sea Basin Deep Water (>2,000 m) located at the southwest of the Bering Basin because of the release of resuspension in 2,000 m depth and the DMSP production from endogenous benthic bacteria and cyanobacteria population. Chl a was positively correlated with DMSPp and DMS in the surface waters and the upper water of the basin, whereas significant negative correlations were found between DMS and nutrients (dissolved inorganic nitrogen [DIN], phosphorus, and silicate) in the inner shelf of the Bering Sea. DMS microbial consumption was approximately 6.26 times faster than the DMS sea-air exchange, demonstrating that the major loss of DMS in the surface water occurred through biological consumption relative to evasion into the atmosphere. Average sea-to-air DMS fluxes were estimated to be 4.66 μmol/(m2·d), and consequently oceanic biogenic DMS emission had a dominant contribution to the sulfur budget over the observational area.

  19. Catalyst for the reduction of sulfur dioxide to elemental sulfur

    Science.gov (United States)

    Jin, Y.; Yu, Q.; Chang, S.G.

    1996-02-27

    The inventive catalysts allow for the reduction of sulfur dioxide to elemental sulfur in smokestack scrubber environments. The catalysts have a very high sulfur yield of over 90% and space velocity of 10,000 h{sup {minus}1}. They also have the capacity to convert waste gases generated during the initial conversion into elemental sulfur. The catalysts have inexpensive components, and are inexpensive to produce. The net impact of the invention is to make this technology practically available to industrial applications. 21 figs.

  20. Characterization of hydrogen, nitrogen, oxygen, carbon and sulfur in nuclear fuel (UO2) and cladding nuclear rod materials

    International Nuclear Information System (INIS)

    Crewe, Maria Teresa I.; Lopes, Paula Corain; Moura, Sergio C.; Sampaio, Jessica A.G.; Bustillos, Oscar V.

    2011-01-01

    The importance of Hydrogen, Nitrogen, Oxygen, Carbon and Sulfur gases analysis in nuclear fuels such as UO 2 , U 3 O 8 , U 3 Si 2 and in the fuel cladding such as Zircaloy, is a well known as a quality control in nuclear industry. In UO 2 pellets, the Hydrogen molecule fragilizes the metal lattice causing the material cracking. In Zircaloy material the H2 molecules cause the boiling of the cladding. Other gases like Nitrogen, Oxygen, Carbon and Sulfur affect in the lattice structure change. In this way these chemical compounds have to be measure within specify parameters, these measurement are part of the quality control of the nuclear industry. The analytical procedure has to be well established by a convention of the quality assurance. Therefore, the Oxygen, Carbon, Sulfur and Hydrogen are measured by infrared absorption (IR) and the nitrogen will be measured by thermal conductivity (TC). The gas/metal analyzer made by LECO Co. model TCHEN-600 is Hydrogen, Oxygen and Nitrogen analyzer in a variety of metals, refractory and other inorganic materials, using the principle of fusion by inert gas, infrared and thermo-coupled detector. The Carbon and Sulfur compounds are measure by LECO Co. model CS-400. A sample is first weighed and placed in a high purity graphite crucible and is casted on a stream of helium gas, enough to release the oxygen, nitrogen and hydrogen. During the fusion, the oxygen present in the sample combines with the carbon crucible to form carbon monoxide. Then, the nitrogen present in the sample is analyzed and released as molecular nitrogen and the hydrogen is released as gas. The hydrogen gas is measured by infrared absorption, and the sample gases pass through a trap of copper oxide which converts CO to CO 2 and hydrogen into water. The gases enter the cell where infrared water content is then converted making the measurement of total hydrogen present in the sample. The Hydrogen detection limits for the nuclear fuel is 1 μg/g for the Nitrogen

  1. Workshop on sulfur chemistry in flue gas desulfurization

    Energy Technology Data Exchange (ETDEWEB)

    Wallace, W.E. Jr.

    1980-05-01

    The Flue Gas Desulfurization Workshop was held at Morgantown, West Virginia, June 7-8, 1979. The presentations dealt with the chemistry of sulfur and calcium compounds in scrubbers. DOE and EPRI programs in this area are described. Ten papers have been entered individually into EDB and ERA. (LTN)

  2. A XANES Study of Sulfur Speciation and Reactivity in Cokes for Anodes Used in Aluminum Production

    Science.gov (United States)

    Jahrsengene, Gøril; Wells, Hannah C.; Rørvik, Stein; Ratvik, Arne Petter; Haverkamp, Richard G.; Svensson, Ann Mari

    2018-06-01

    Availability of anode raw materials in the growing aluminum industry results in a wider range of petroleum cokes being used to produce carbon anodes. The boundary between anode grade cokes and what previously was considered non-anode grades are no longer as distinct as before, leading to introduction of cokes with higher sulfur and higher trace metal impurity content in anode manufacturing. In this work, the chemical nature of sulfur in five industrial cokes, ranging from 1.42 to 5.54 wt pct S, was investigated with K-edge XANES, while the reactivity of the cokes towards CO2 was measured by a standard mass loss test. XANES identified most of the sulfur as organic sulfur compounds. In addition, a significant amount is identified (16 to 53 pct) as S-S bound sulfur. A strong inverse correlation is observed between CO2-reactivity and S-S bound sulfur in the cokes, indicating that the reduction in reactivity is more dependent on the amount of this type of sulfur compound rather than the total amount of sulfur or the amount of organic sulfur.

  3. Method of removing and recovering elemental sulfur from highly reducing gas streams containing sulfur gases

    Science.gov (United States)

    Gangwal, Santosh K.; Nikolopoulos, Apostolos A.; Dorchak, Thomas P.; Dorchak, Mary Anne

    2005-11-08

    A method is provided for removal of sulfur gases and recovery of elemental sulfur from sulfur gas containing supply streams, such as syngas or coal gas, by contacting the supply stream with a catalyst, that is either an activated carbon or an oxide based catalyst, and an oxidant, such as sulfur dioxide, in a reaction medium such as molten sulfur, to convert the sulfur gases in the supply stream to elemental sulfur, and recovering the elemental sulfur by separation from the reaction medium.

  4. The metal-driven biogeochemistry of gaseous compounds in the environment

    CERN Document Server

    Kroneck, Peter MH

    2014-01-01

    MILS-14 provides a most up-to-date view of the exciting biogeochemistry of gases in our environment as driven mostly by microorganisms. These employ a machinery of sophisticated metalloenzymes, where especially transition metals (such as Fe, Ni, Cu, Mo, W) play a fundamental role, that is, in the activation, transformation and syntheses of gases like dihydrogen, methane, carbon monoxide, acetylene and those of the biological nitrogen and sulfur cycles. The Metal-Driven Biogeochemistry of Gaseous Compounds in the Environment is a vibrant research area based mainly on structural and microbial biology, inorganic biological chemistry and environmental biochemistry. All this is covered in an authoritative manner in 11 stimulating chapters, written by 26 internationally recognized experts and supported by nearly 1200 references, informative tables and about 100 illustrations (two thirds in color). MILS-14 also provides excellent information for teaching. Peter M. H. Kroneck is a bioinorganic chemist who is explorin...

  5. Transformation of Nitrate and Toluene in Groundwater by Sulfur Modified Iron(SMI-III)

    Science.gov (United States)

    Lee, W.; Park, S.; Lim, J.; Hong, U.; Kwon, S.; Kim, Y.

    2009-12-01

    In Korea, nitrate and benzene, toluene, ethylbenzene, and xylene isomers (BTEX) are frequently detected together as ground water contaminants. Therefore, a system simultaneously treating both nitrate (inorganic compound) and BTEX (organic compounds) is required to utilize groundwater as a water resource. In this study, we investigated the efficiency of Sulfur Modified Iron (SMI-III) in treating both nitrate and BTEX contaminated groundwater. Based on XRD (X-Ray Diffraction) analysis, the SMI-III is mainly composed of Fe3O4, S, and Fe. A series of column tests were conducted at three different empty bed contact times (EBCTs) for each compound. During the experiments, removal efficiency for both nitrate and toluene were linearly correlated with EBCT, suggesting that SMI-III have an ability to transform both nitrate and toluene. The concentration of SO42- and oxidation/reduction potential (ORP) were also measured. After exposed to nitrate contaminated groundwater, the composition of SMI-III was changed to Fe2O3, Fe3O4, Fe, and Fe0.95S1.05. The trends of effluent sulfate concentrations were inversely correlated with effluent nitrate concentrations, while the trends of ORP values, having the minimum values of -480 mV, were highly correlated with effluent nitrate concentrations. XRD analysis before and after exposed to nitrate contaminated groundwater, sulfate production, and nitrite detection as a reductive transformation by-product of nitrate suggest that nitrate is reductively transformed by SMI-III. Interestingly, in the toluene experiments, the trends of ORP values were inversely correlated with effluent toluene concentrations, suggesting that probably degrade through oxidation reaction. Consequently, nitrate and toluene probably degrade through reduction and oxidation reaction, respectively and SMI-III could serve as both electron donor and acceptor.

  6. Isotope dilution mass spectrometry of inorganic and organic substances

    International Nuclear Information System (INIS)

    Heumann, K.G.

    1986-01-01

    The aim of this short review of IDMS is to provide an introduction into the principles of this analytical method and to show possible applications of this accurate technique, e.g. negative thermal ionization IDMS for inorganic anion analysis or the analysis of organic compounds in the field of clinical chemistry. (orig./RB)

  7. Ice nucleation in sulfuric acid/organic aerosols: implications for cirrus cloud formation

    Directory of Open Access Journals (Sweden)

    M. R. Beaver

    2006-01-01

    Full Text Available Using an aerosol flow tube apparatus, we have studied the effects of aliphatic aldehydes (C3 to C10 and ketones (C3 and C9 on ice nucleation in sulfuric acid aerosols. Mixed aerosols were prepared by combining an organic vapor flow with a flow of sulfuric acid aerosols over a small mixing time (~60 s at room temperature. No acid-catalyzed reactions were observed under these conditions, and physical uptake was responsible for the organic content of the sulfuric acid aerosols. In these experiments, aerosol organic content, determined by a Mie scattering analysis, was found to vary with the partial pressure of organic, the flow tube temperature, and the identity of the organic compound. The physical properties of the organic compounds (primarily the solubility and melting point were found to play a dominant role in determining the inferred mode of nucleation (homogenous or heterogeneous and the specific freezing temperatures observed. Overall, very soluble, low-melting organics, such as acetone and propanal, caused a decrease in aerosol ice nucleation temperatures when compared with aqueous sulfuric acid aerosol. In contrast, sulfuric acid particles exposed to organic compounds of eight carbons and greater, of much lower solubility and higher melting temperatures, nucleate ice at temperatures above aqueous sulfuric acid aerosols. Organic compounds of intermediate carbon chain length, C4-C7, (of intermediate solubility and melting temperatures nucleated ice at the same temperature as aqueous sulfuric acid aerosols. Interpretations and implications of these results for cirrus cloud formation are discussed.

  8. Steep spatial gradients of volcanic and marine sulfur in Hawaiian rainfall and ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Bern, Carleton R., E-mail: cbern@usgs.gov [U.S. Geological Survey, Denver Federal Center, Denver, CO 80225 (United States); Department of Geography University of California, Santa Barbara, CA 93106-4060 (United States); Chadwick, Oliver A. [Department of Geography University of California, Santa Barbara, CA 93106-4060 (United States); Kendall, Carol [U.S. Geological Survey, Menlo Park, CA (United States); Pribil, Michael J. [U.S. Geological Survey, Denver Federal Center, Denver, CO 80225 (United States)

    2015-05-01

    Sulfur, a nutrient required by terrestrial ecosystems, is likely to be regulated by atmospheric processes in well-drained, upland settings because of its low concentration in most bedrock and generally poor retention by inorganic reactions within soils. Environmental controls on sulfur sources in unpolluted ecosystems have seldom been investigated in detail, even though the possibility of sulfur limiting primary production is much greater where atmospheric deposition of anthropogenic sulfur is low. Here we measure sulfur isotopic compositions of soils, vegetation and bulk atmospheric deposition from the Hawaiian Islands for the purpose of tracing sources of ecosystem sulfur. Hawaiian lava has a mantle-derived sulfur isotopic composition (δ{sup 34}S VCDT) of − 0.8‰. Bulk deposition on the island of Maui had a δ{sup 34}S VCDT that varied temporally, spanned a range from + 8.2 to + 19.7‰, and reflected isotopic mixing from three sources: sea-salt (+ 21.1‰), marine biogenic emissions (+ 15.6‰), and volcanic emissions from active vents on Kilauea Volcano (+ 0.8‰). A straightforward, weathering-driven transition in ecosystem sulfur sources could be interpreted in the shift from relatively low (0.0 to + 2.7‰) to relatively high (+ 17.8 to + 19.3‰) soil δ{sup 34}S values along a 0.3 to 4100 ka soil age-gradient, and similar patterns in associated vegetation. However, sub-kilometer scale spatial variation in soil sulfur isotopic composition was found along soil transects assumed by age and mass balance to be dominated by atmospheric sulfur inputs. Soil sulfur isotopic compositions ranged from + 8.1 to + 20.3‰ and generally decreased with increasing elevation (0–2000 m), distance from the coast (0–12 km), and annual rainfall (180–5000 mm). Such trends reflect the spatial variation in marine versus volcanic inputs from atmospheric deposition. Broadly, these results illustrate how the sources and magnitude of atmospheric deposition can exert controls

  9. Steep spatial gradients of volcanic and marine sulfur in Hawaiian rainfall and ecosystems

    International Nuclear Information System (INIS)

    Bern, Carleton R.; Chadwick, Oliver A.; Kendall, Carol; Pribil, Michael J.

    2015-01-01

    Sulfur, a nutrient required by terrestrial ecosystems, is likely to be regulated by atmospheric processes in well-drained, upland settings because of its low concentration in most bedrock and generally poor retention by inorganic reactions within soils. Environmental controls on sulfur sources in unpolluted ecosystems have seldom been investigated in detail, even though the possibility of sulfur limiting primary production is much greater where atmospheric deposition of anthropogenic sulfur is low. Here we measure sulfur isotopic compositions of soils, vegetation and bulk atmospheric deposition from the Hawaiian Islands for the purpose of tracing sources of ecosystem sulfur. Hawaiian lava has a mantle-derived sulfur isotopic composition (δ 34 S VCDT) of − 0.8‰. Bulk deposition on the island of Maui had a δ 34 S VCDT that varied temporally, spanned a range from + 8.2 to + 19.7‰, and reflected isotopic mixing from three sources: sea-salt (+ 21.1‰), marine biogenic emissions (+ 15.6‰), and volcanic emissions from active vents on Kilauea Volcano (+ 0.8‰). A straightforward, weathering-driven transition in ecosystem sulfur sources could be interpreted in the shift from relatively low (0.0 to + 2.7‰) to relatively high (+ 17.8 to + 19.3‰) soil δ 34 S values along a 0.3 to 4100 ka soil age-gradient, and similar patterns in associated vegetation. However, sub-kilometer scale spatial variation in soil sulfur isotopic composition was found along soil transects assumed by age and mass balance to be dominated by atmospheric sulfur inputs. Soil sulfur isotopic compositions ranged from + 8.1 to + 20.3‰ and generally decreased with increasing elevation (0–2000 m), distance from the coast (0–12 km), and annual rainfall (180–5000 mm). Such trends reflect the spatial variation in marine versus volcanic inputs from atmospheric deposition. Broadly, these results illustrate how the sources and magnitude of atmospheric deposition can exert controls over

  10. Selective inorganic thin films

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, M.L.F.; Weisenbach, L.A.; Anderson, M.T. [Sandia National Laboratories, Albuquerque, NM (United States)] [and others

    1995-05-01

    This project is developing inorganic thin films as membranes for gas separation applications, and as discriminating coatings for liquid-phase chemical sensors. Our goal is to synthesize these coatings with tailored porosity and surface chemistry on porous substrates and on acoustic and optical sensors. Molecular sieve films offer the possibility of performing separations involving hydrogen, air, and natural gas constituents at elevated temperatures with very high separation factors. We are focusing on improving permeability and molecular sieve properties of crystalline zeolitic membranes made by hydrothermally reacting layered multicomponent sol-gel films deposited on mesoporous substrates. We also used acoustic plate mode (APM) oscillator and surface plasmon resonance (SPR) sensor elements as substrates for sol-gel films, and have both used these modified sensors to determine physical properties of the films and have determined the sensitivity and selectivity of these sensors to aqueous chemical species.

  11. Inorganic Halogen Oxidizer Research

    Science.gov (United States)

    1979-02-16

    Inorganic Chemistry. Vol. 14. No. 9. 1975 Karl 0. Christ¢ (21) L. J. Basile . P. LaBonvillk. J. R. Ferraro, and J. M. Williams. J. Claim. (38) K. 0. Chriae. E... basils of a nonplanar structure of symmetry CI, are revised for six fundamental frequencies. Imalredetle either the 1:2 adduct N 2F4.2SbF5 or the 1:3...8217 in mT are 7 2.1 for B, facility. We aba thank L. K. White and R. L. Belford 111.0 for C, 55.0 for N, and 17100 for F, and the atomic aniso- trop’c

  12. Modern Trends in Inorganic Chemistry

    Indian Academy of Sciences (India)

    Administrator

    The series of symposia on 'Modern Trends in Inorganic Chemistry' (MTIC), which began in 1985 at the Indian Association for Cultivation of Science, Calcutta has evolved into a forum for the Inorganic Chemistry fraternity of the country to meet every two years and discuss the current status and future projections of research in.

  13. Enantioselctive Syntheses of Sulfur Analogues of Flavan-3-Ols

    Directory of Open Access Journals (Sweden)

    Richard Lombardy

    2010-08-01

    Full Text Available The first enantioselective syntheses of sulfur flavan-3-ol analogues 1–8 have been accomplished, whereby the oxygen atom of the pyran ring has been replaced by a sulfur atom. The key steps were: (a Pd(0 catalyzed introduction of –S t-butyl group, (b Sharpless enantioselective dihydroxylation of the alkene, (c acid catalyzed ring closure to produce the thiopyran ring, and (d removal of benzyl groups using N,N-dimethylaniline and AlCl3. The compounds were isolated in high chemical and optical purity.

  14. Durability of solid oxide fuel cells using sulfur containing fuels

    DEFF Research Database (Denmark)

    Hagen, Anke; Rasmussen, Jens Foldager Bregnballe; Thydén, Karl Tor Sune

    2011-01-01

    The usability of hydrogen and also carbon containing fuels is one of the important advantages of solid oxide fuel cells (SOFCs), which opens the possibility to use fuels derived from conventional sources such as natural gas and from renewable sources such as biogas. Impurities like sulfur compounds...... are critical in this respect. State-of-the-art Ni/YSZ SOFC anodes suffer from being rather sensitive towards sulfur impurities. In the current study, anode supported SOFCs with Ni/YSZ or Ni/ScYSZ anodes were exposed to H2S in the ppm range both for short periods of 24h and for a few hundred hours. In a fuel...

  15. Computer-Assisted Inverse Design of Inorganic Electrides

    Directory of Open Access Journals (Sweden)

    Yunwei Zhang

    2017-02-01

    Full Text Available Electrides are intrinsic electron-rich materials enabling applications as excellent electron emitters, superior catalysts, and strong reducing agents. There are a number of organic electrides; however, their instability at room temperature and sensitivity to moisture are bottlenecks for their practical uses. Known inorganic electrides are rare, but they appear to have greater thermal stability at ambient conditions and are thus better characterized for application. Here, we develop a computer-assisted inverse-design method for searching for a large variety of inorganic electrides unbiased by any known electride structures. It uses the intrinsic property of interstitial electron localization of electrides as the global variable function for swarm intelligence structure searches. We construct two rules of thumb on the design of inorganic electrides pointing to electron-rich ionic systems and low electronegativity of the cationic elements involved. By screening 99 such binary compounds through large-scale computer simulations, we identify 24 stable and 65 metastable new inorganic electrides that show distinct three-, two-, and zero-dimensional conductive properties, among which 18 are existing compounds that have not been pointed to as electrides. Our work reveals the rich abundance of inorganic electrides by providing 33 hitherto unexpected structure prototypes of electrides, of which 19 are not in the known structure databases.

  16. Holographic patterning of organic-inorganic photopolymerizable nanocomposites

    Science.gov (United States)

    Sakhno, Oksana V.; Goldenberg, Leonid M.; Smirnova, Tatiana N.; Stumpe, J.

    2009-09-01

    We present here novel easily processible organic-inorganic nanocomposites suitable for holographic fabrication of diffraction optical elements (DOE). The nanocomposites are based on photocurable acrylate monomers and inorganic nanoparticles (NP). The compatibility of inorganic NP with monomers was achieved by capping the NP surface with proper organic shells. Surface modification allows to introduce up to 50wt.% of inorganic NP in organic media. Depending on the NP nature (metal oxides, phosphates, semiconductors, noble metals) and their properties, the materials for both efficient DOE and multifunctional elements can be designed. Organic-inorganic composites prepared have been successfully used for the effective inscription of periodic volume refractive index structures using the holographic photopolymerization method. The nanocomposite preparation procedure, their properties and optical performance of holographic gratings are reported. The use of functional NP makes it possible to obtain effective holographic gratings having additional physical properties such as light-emission or NLO. Some examples of such functional polymer-NP structures and their possible application fields are presented. The combination of easy photo-patterning of soft organic compounds with physical properties of inorganic materials in new nanocomposites and the flexibility of the holographic patterning method allow the fabrication of mono- and multifunctional one- and multi-dimensional passive or active optical and photonic elements.

  17. Danburite decomposition by sulfuric acid

    International Nuclear Information System (INIS)

    Mirsaidov, U.; Mamatov, E.D.; Ashurov, N.A.

    2011-01-01

    Present article is devoted to decomposition of danburite of Ak-Arkhar Deposit of Tajikistan by sulfuric acid. The process of decomposition of danburite concentrate by sulfuric acid was studied. The chemical nature of decomposition process of boron containing ore was determined. The influence of temperature on the rate of extraction of boron and iron oxides was defined. The dependence of decomposition of boron and iron oxides on process duration, dosage of H 2 SO 4 , acid concentration and size of danburite particles was determined. The kinetics of danburite decomposition by sulfuric acid was studied as well. The apparent activation energy of the process of danburite decomposition by sulfuric acid was calculated. The flowsheet of danburite processing by sulfuric acid was elaborated.

  18. 40 CFR Table 27 to Subpart Uuu of... - Continuous Compliance With Inorganic HAP Emission Limits for Catalytic Reforming Units

    Science.gov (United States)

    2010-07-01

    ... HAP Emission Limits for Catalytic Reforming Units 27 Table 27 to Subpart UUU of Part 63 Protection of... Pollutants for Petroleum Refineries: Catalytic Cracking Units, Catalytic Reforming Units, and Sulfur Recovery... Inorganic HAP Emission Limits for Catalytic Reforming Units As stated in § 63.1567(c)(1), you shall meet...

  19. FABRICATION OF ZNS THIN FILM FOR INORGANIC EL BY THE VACCUUM EVAPORATION

    OpenAIRE

    龍見, 雅美; 島谷, 圭市; 小西, 信行; 元木, 健作

    2008-01-01

    "Zinc sulfide is a typical material for inorganic electroluminescent(EL) device. Recently very high luminance and life time e has been reported on an inorganic EL device based on thin film zinc sulfide material. The present study tries to realize high quality zinc sulfide thin film for EL device. The thin film was grown by the vacuum evaporation method. In order to obtain stoichiometric thin film, the vacuum evaporation was carried out in a quasi-closed vessel under a condition of sulfur atmo...

  20. Effects of Different Level and Source of Sulfur Supplement in Close-up diets of Dairy Cows on Blood Metabolites, Colostrums Composition and Liver Performance

    Directory of Open Access Journals (Sweden)

    E Manidari

    2012-01-01

    Full Text Available The 24 maltiparous Holstein dairy cows were allocated in a completely randomized design to study the effects of different level and source of sulfur supplement in close-up diets on blood metabolites, colostrums composition and liver performance. The mean body weight of the cows was 687.9 kg and the mean days until expected calving date was 21.8 d. The first treatment (T1 has contained 0.21% sulfur (DM basis, the second treatment (T2 has contained 0.41% sulfur which supplied entirely through magnesium sulfate and the third treatment (T3 has contained 0.41% sulfur which supplied through a combination of magnesium sulfate and an organic source of sulfur (Mepran. The DMI for pre-calving (P < 0.001 was affected by treatments and T2 showed the lowest DMI among treatments. Colostrums yield, protein, DM and ash significantly decreased in inorganic sulfur supplemented treatment (P < 0.05. Among the blood metabolites, calcium, copper and glucose were decreased in T2 compared with two other treatments (P < 0.05. However, BHBA, NEFA and urea were increased in T2 (P < 0.05. Urine pH was affected with different treatments (P < 0.0001. The both liver enzymes (i.e. AST and CPK were increased supplementing inorganic sulfur showing that inorganic sulfur has potential to decrease liver performance in dairy cows. The results of the present study indicate that although magnesium sulfate (inorganic source has negative effect on dairy cow health and performance, a combination of magnesium sulfate and organic source of sulfur could have positive effects on dry matter intake, blood metabolites and liver health in dairy cows.

  1. Scintillation properties of (C sub 6 H sub 1 sub 3 NH sub 3) sub 2 PbI sub 4 Exciton luminescence of an organic/inorganic multiple quantum well structure compound induced by 2.0 MeV protons

    CERN Document Server

    Shibuya, K; Takeoka, Y; Asai, K

    2002-01-01

    We report a new type of scintillator especially suitable for pulse-radiation detection. Thin films of organic/inorganic perovskite compound (n-C sub 6 H sub 1 sub 3 NH sub 3) sub 2 PbI sub 4 , which is characterized by a multiple quantum well structure, were bombarded by 2.0 MeV protons, and their radiation-induced emission spectra were obtained. A single and sharp emission peak due to an exciton was observed at the wavelength of 524 nm. This emission was clearly detected even at room temperature, and its quantum efficiency was very high. The line shape of this emission did not change, retaining its sharpness, and no other emissions appeared throughout the irradiation. The optical response of (n-C sub 6 H sub 1 sub 3 NH sub 3) sub 2 PbI sub 4 is very fast. (n-C sub 6 H sub 1 sub 3 NH sub 3) sub 2 PbI sub 4 is a promising scintillator material, meeting requirements not satisfied by conventional scintillators.

  2. Contribution to the study by infrared spectroscopy of addition compounds of boron fluorides and ethers-oxides or organic sulphides; Contribution a l'etude par spectroscopie infrarouge des composes d'addition des fluorures de bore et des ethers-oxydes ou des sulfures organiques

    Energy Technology Data Exchange (ETDEWEB)

    Le Calve, Jacques

    1964-03-09

    This research thesis reports the study of complexes formed with boron fluoride and ethers or organic sulphides. In a first part, the author recalls vibration modes of free boron fluoride and of this compound in a complex. In the next parts, he reports the analysis of infrared spectra of groups present in addition compounds (between 400 and 1500 cm{sup -1}). He discusses spectrum modifications of electron donors by formation of a coordination bound. Experimental conditions are presented in appendix [French] Nous avons enregistre les spectres infrarouges de 400 a 4000 cm{sup -1} des composes d'addition du fluorure de bore et des oxydes de methyle, d'ethyle et du tetrahydrofuranne a l'etat gazeux, a l'etat liquide et a - 180 deg. a l'etat solide. Nous avons egalement etudie les complexes du fluorure de bore et des sulfures de methyle, d'ethyle et du tetrahydrothiophene a l'etat liquide. Le groupement c-c-OBF{sub 3} des trois composes des ethers avait fait l'objet d'une analyse tres recente que nous avons discutee. La comparaison des spectres et leur evolution en fonction de l'etat physique nous a notamment permis de mettre en evidence un couplage des vibrations de valence symetrique ν{sub s}(BF{sub 3}) et ν(OB) avec celles de meme symetrie du squelette de l'ether, en particulier la vibration ν{sub s}(COC). Ce couplage rend illusoires les correlations qui avaient ete proposees entre la basicite du donneur et la position d'une bande attribuee hativement a la vibration ν{sub s}(BF{sub 3}). Pour les composes d'addition des sulfures, nous avons attribue les principales vibrations du groupement C-C-SBF{sub 3}. La vibration de valence degeneree ν{sub s}(BF{sub 3}) apparait vers 1180 cm{sup -1}. Les vibrations de valence symetriques ν{sub s}(BF{sub 3}) et ν(SB) sont couplees et se manifestent dans les spectres par deux bandes vers 800 et 600 cm{sup -1}. Enfin, une absorption vers 460 cm{sup -1} correspond a l'une des vibrations de deformation symetrique ou degeneree

  3. Large scale disposal of waste sulfur: From sulfide fuels to sulfate sequestration

    International Nuclear Information System (INIS)

    Rappold, T.A.; Lackner, K.S.

    2010-01-01

    Petroleum industries produce more byproduct sulfur than the market can absorb. As a consequence, most sulfur mines around the world have closed down, large stocks of yellow sulfur have piled up near remote operations, and growing amounts of toxic H 2 S are disposed of in the subsurface. Unless sulfur demand drastically increases or thorough disposal practices are developed, byproduct sulfur will persist as a chemical waste problem on the scale of 10 7 tons per year. We review industrial practices, salient sulfur chemistry, and the geochemical cycle to develop sulfur management concepts at the appropriate scale. We contend that the environmentally responsible disposal of sulfur would involve conversion to sulfuric acid followed by chemical neutralization with equivalent amounts of base, which common alkaline rocks can supply cheaply. The resulting sulfate salts are benign and suitable for brine injection underground or release to the ocean, where they would cause minimal disturbance to ecosystems. Sequestration costs can be recouped by taking advantage of the fuel-grade thermal energy released in the process of oxidizing reduced compounds and sequestering the products. Sulfate sequestration can eliminate stockpiles and avert the proliferation of enriched H 2 S stores underground while providing plenty of carbon-free energy to hydrocarbon processing.

  4. Combustion synthesis of inorganic materials; Muki zairyo no nensho gose

    Energy Technology Data Exchange (ETDEWEB)

    Oyanagi, M. [Ryukoku University, Kyoto (Japan)

    1999-11-01

    Combustion synthesis of porous titan carbide is outlined. In combustion synthesis, exothermic chain reaction, which is induced by igniting at one point of the simple substance mixture, propagates the combustion wave, and the compound is synthesized, which can be sintered by it. By this method, to this day intermetallic compounds, ceramics and high melting point composite materials have been synthesized, and synthetics can be made compact by adding pressure during or just after the reaction. Recently, applying the induction heating jointly, preheating before the reaction and heat treatment after the reaction can be controlled, accordingly, many high melting point inorganic compounds and composite materials can be made by combustion synthesis under pressure. (NEDO)

  5. Forecasting of heat capacity of molecular inorganic liquids

    International Nuclear Information System (INIS)

    Sladkov, I.B.; Neganov, O.S.

    1992-01-01

    On the basis of analysis of experimental material on heat capacity of liquids, covering 350 molecular inorganic compounds, atomic parts of heat capacity for 58 elements of the Periodic system were obtained. Data on the accuracy of heat capacity calculation by the Neumann-Kopp rule using the recommended atomic parts C p are presented. For the Kelli rule it is assertained that the factor of proportiomality between heat capacity and the number of atoms in compound molecule in the general case depends on the type of anion and compound coordination. The Neumann-Kopp-Kelli rules provide a satisfactory accuracy of prediction

  6. Cancer risk from inorganics

    International Nuclear Information System (INIS)

    Swierenga, S.H.; Gilman, J.P.; McLean, J.R.

    1987-01-01

    Inorganic metals and minerals for which there is evidence of carcinogenicity are identified. The risk of cancer from contact with them in the work place, the general environment, and under conditions of clinical (medical) exposure is discussed. The evidence indicates that minerals and metals most often influence cancer development through their action as cocarcinogens. The relationship between the physical form of mineral fibers, smoking and carcinogenic risk is emphasized. Metals are categorized as established (As, Be, Cr, Ni), suspected (Cd, Pb) and possible carcinogens, based on the existing in vitro, animal experimental and human epidemiological data. Cancer risk and possible modes of action of elements in each class are discussed. Views on mechanisms that may be responsible for the carcinogenicity of metals are updated and analysed. Some specific examples of cancer risks associated with the clinical use of potentially carcinogenic metals and from radioactive pharmaceuticals used in therapy and diagnosis are presented. Questions are raised as to the effectiveness of conventional dosimetry in accurately measuring risk from radiopharmaceuticals. 302 references

  7. Demand outlook for sulfur and high-sulfur petroleum coke

    Energy Technology Data Exchange (ETDEWEB)

    Koshkarov, V.Ya.; Danil' yan, P.G.; Feotov, V.E.; Gimaev, R.N.; Koshkarova, M.E.; Sadykova, S.R.; Vodovichenko, N.S.

    1980-01-01

    The feasibility of using sulfur and high-sulfur petroleum coke fines in pyrometallurgical processes and also in the chemical and coal-tar chemical industry is examined. Results of industrial tests on briquetting fines of petroleum coke with a petroleum binder are presented. The feasibility of using the obtained briquets in shaft furnace smelting of oxidized nickel ores, production of anode stock, and also in the chemical industry are demonstrated.

  8. Effects of inorganic substances on water splitting in ion-exchange membranes; II. Optimal contents of inorganic substances in preparing bipolar membranes.

    Science.gov (United States)

    Kang, Moon-Sung; Choi, Yong-Jin; Moon, Seung-Hyeon

    2004-05-15

    An approach to enhancing the water-splitting performance of bipolar membranes (BPMs) is introducing an inorganic substance at the bipolar (BP) junction. In this study, the immobilization of inorganic matters (i.e., iron hydroxides and silicon compounds) at the BP junction and the optimum concentration have been investigated. To immobilize these inorganic matters, novel methods (i.e., electrodeposition of the iron hydroxide and processing of the sol-gel to introduce silicon groups at the BP junction) were suggested. At optimal concentrations, the immobilized inorganic matters significantly enhanced the water-splitting fluxes, indicating that they provide alternative paths for water dissociation, but on the other hand possibly reduce the polarization of water molecules between the sulfonic acid and quaternary ammonium groups at high contents. Consequently, the amount of inorganic substances introduced should be optimized to obtain the maximum water splitting in the BPM.

  9. Protonation of inorganic 5-Fluorocytosine salts

    Science.gov (United States)

    Souza, Matheus S.; da Silva, Cecília C. P.; Almeida, Leonardo R.; Diniz, Luan F.; Andrade, Marcelo B.; Ellena, Javier

    2018-06-01

    5-Fluorocytosine (5-FC) has been widely used for the treatment of fungal infections and recently was found to exert an extraordinary antineoplastic activity in gene directed prodrug therapy. However, despite of its intense use, 5-FC exhibits tabletability issues due its physical instability in humid environments, leading to transition from the anhydrous to monohydrate phase. By considering that salt formation is an interesting strategy to overcome this problem, in this paper crystal engineering approach was applied to the supramolecular synthesis of new 5-FC salts with sulfuric, hydrobromic and methanesulfonic inorganic acids. A total of four structures were obtained, namely 5-FC sulfate monohydrate (1:1:1), 5-FC hydrogen sulfate (1:1), 5-FC mesylate (1:1) and 5-FC hydrobromide (1:1), the last one being a polymorphic form of a structure already reported in the literature. These novel salts were structurally characterized by single crystal X-ray diffraction and its supramolecular organization were analyses by Hirshfeld surface analysis. The vibrational behavior was evaluated by Raman spectroscopy and it was found to be consistent with the crystal structures.

  10. Volcanogenic Sulfur on Earth and Io: Composition and Spectroscopy

    Science.gov (United States)

    Kargel, J.S.; Delmelle, P.; Nash, D.B.

    1999-01-01

    The causes of Io's variegated surface, especially the roles of sulfur, and the geochemical history of sulfur compounds on Io are not well understood. Suspecting that minor impurities in sulfur might be important, we have investigated the major and trace element chemistry and spectroscopic reflectance of natural sulfur from a variety of terrestrial volcanic-hydrothermal environments. Evidence suggests that Io may be substantially coated with impure sulfur. On Earth, a few tenths of a percent to a few percent of chalcophile trace elements (e.g., As and Se) comonly occur in sulfur and appear to stabilize material of yellow, brown, orange, and red hues, which may persist even at low temperatures. Percentage levels of chalcophile impurities are reasonably expected to occur on Io in vapor sublimate deposits and flows derived from such deposits. Such impurities join a host of other mechanisms that might explain Io's reds and yellows. Two-tenths to two percent opaque crystalline impurities, particularly pyrite (FeS2), commonly produces green, gray, and black volcanic sulfur on Earth and might explain areas of Io having deposits of these colors. Pyrite produces a broad absorption near 1 ??m that gradually diminishes out to 1.6 ??m - similar but not identical to the spectrum of Io seen in Galileo NIMS data. Percentage amounts of carbonaceous impurities and tens of percent SiO2 (as silicates) also strongly affect the spectral properties of Earth's sulfur. Io's broad absorption between 0.52 and 0.64 ??m remains unexplained by these data but could be due to sodium sulfides, as suggested previously by others, or to As, Se, or other impurities. These impurities and others, such as P and Cl (which could exist on Io's surface in amounts over 1% that of sulfur), greatly alter the molecular structure of molten and solid sulfur. Minor impurities could impact Io's geology, such as the morphology of sulfur lava flows and the ability of sulfur to sustain high relief. We have not found

  11. Inhibition of phosphorylation and incorporation of thymidine in Duckweed (Lemna minor L. ) by sulfur dioxide and sulfite

    Energy Technology Data Exchange (ETDEWEB)

    Braendle, R; Stoeckli, B; Erismann, K H

    1975-05-15

    As there appears to be no thymidine kinase in duckweed (Lemna minor L.), thymidine seems to be phosphorylated by a nucleoside phosphotransferase. Phosphorylation and incorporation are inhibited by sulfur compounds such as sulfur dioxide and sulfite. The data are discussed in relation to the physiological effect of the air pollutant (SO2) on plant life. 12 references, 2 tables.

  12. Organic-Inorganic Perovskites: Structural Versatility for Functional Materials Design.

    Science.gov (United States)

    Saparov, Bayrammurad; Mitzi, David B

    2016-04-13

    Although known since the late 19th century, organic-inorganic perovskites have recently received extraordinary research community attention because of their unique physical properties, which make them promising candidates for application in photovoltaic (PV) and related optoelectronic devices. This review will explore beyond the current focus on three-dimensional (3-D) lead(II) halide perovskites, to highlight the great chemical flexibility and outstanding potential of the broader class of 3-D and lower dimensional organic-based perovskite family for electronic, optical, and energy-based applications as well as fundamental research. The concept of a multifunctional organic-inorganic hybrid, in which the organic and inorganic structural components provide intentional, unique, and hopefully synergistic features to the compound, represents an important contemporary target.

  13. Graphene-sulfur nanocomposites for rechargeable lithium-sulfur battery electrodes

    Science.gov (United States)

    Liu, Jun; Lemmon, John P; Yang, Zhenguo; Cao, Yuiliang; Li, Xiaolin

    2014-06-17

    Rechargeable lithium-sulfur batteries having a cathode that includes a graphene-sulfur nanocomposite can exhibit improved characteristics. The graphene-sulfur nanocomposite can be characterized by graphene sheets with particles of sulfur adsorbed to the graphene sheets. The sulfur particles have an average diameter less than 50 nm..

  14. Selective adsorption of refractory sulfur species on active carbons and carbon based CoMo catalyst.

    Science.gov (United States)

    Farag, Hamdy

    2007-03-01

    Adsorption technique could be a reliable alternative in removing to a certain remarkable extent the sulfur species from the feedstock of petroleum oil. The performance of various carbons on adsorption of model sulfur compounds in a simulated feed solution and the sulfur containing compounds in the real gas oil was evaluated. The adsorption experiments have been carried out in a batch scale at ambient temperature and under the atmospheric pressure. In general, the most refractory sulfur compounds in the hydrotreatment reactions were selectively removed and adsorbed. It was found that the adsorbents affinities to dibenzothiophene and 4,6-dimethyldibenzothiophene were much more favored and pronounced than the aromatic matrices like fluorene, 1-methylnaphthalene and 9-methylanthracene. Among the sulfur species, 4,6-dimethyldibenzothiophene was the highest to be removed in terms of both selectivity and capacity over all the present adsorbents. The studied adsorbents showed significant capacities for the polyaromatic thiophenes. The electronic characteristics seem to play a certain role in such behavior. Regeneration of the used adsorbent was successfully attained either by washing it with toluene or by the release of the adsorbates through heat treatment. A suggested adsorptive removal process of sulfur compounds from petroleum distillate over carbon supported CoMo catalyst was discussed.

  15. Essentials of inorganic materials synthesis

    CERN Document Server

    Rao, C N R

    2015-01-01

    This compact handbook describes all the important methods of synthesis employed today for synthesizing inorganic materials. Some features: Focuses on modern inorganic materials with applications in nanotechnology, energy materials, and sustainability Synthesis is a crucial component of materials science and technology; this book provides a simple introduction as well as an updated description of methods Written in a very simple style, providing references to the literature to get details of the methods of preparation when required

  16. New uses of sulfur - update

    Energy Technology Data Exchange (ETDEWEB)

    Almond, K.P.

    1995-07-01

    An update to an extensive bibliography on alternate uses of sulfur was presented. Alberta Sulphur Research Ltd., previously compiled a bibliography in volume 24 of this quarterly bulletin. This update provides an additional 44 new publications. The information regarding current research focusses on topics regarding the use of sulfur in oil and gas applications, mining and metallurgy, concretes and other structural materials, waste management, rubber and textile products, asphalts and other paving and highway applications.

  17. For sale: Sulfur emissions

    International Nuclear Information System (INIS)

    Heiderscheit, J.

    1992-01-01

    The allowance trading market has started a slow march to maturity. Competitive developers should understand the risks and opportunities now presented. The marketplace for sulfur dioxide (SO 2 ) emissions allowances - the centerpiece of Title 4's acid rain reduction program - remains enigmatic 19 months after the Clean Air Act amendments of 1990 were passed. Yet it is increasingly clear that the emission allowance market will likely confound the gloom and doom of its doubters. The recently-announced $10 million dollar Wisconsin Power and Light allowance sales to Duquesne Light and the Tennessee Valley Authority are among the latest indications of momentum toward a stabilizing market. This trend puts additional pressure on independent developers to finalize their allowance strategies. Developers who understand what the allowance trading program is and what it is not, know the key players, and grasp the unresolved regulatory issues will have a new competitive advantage. The topics addressed in this article include the allowance marketplace, marketplace characteristics, the regulatory front, forward-looking strategies, and increasing marketplace activity

  18. Ultrasound-assisted oxidative process for sulfur removal from petroleum product feedstock.

    Science.gov (United States)

    Mello, Paola de A; Duarte, Fábio A; Nunes, Matheus A G; Alencar, Mauricio S; Moreira, Elizabeth M; Korn, Mauro; Dressler, Valderi L; Flores, Erico M M

    2009-08-01

    A procedure using ultrasonic irradiation is proposed for sulfur removal of a petroleum product feedstock. The procedure involves the combination of a peroxyacid and ultrasound-assisted treatment in order to comply with the required sulfur content recommended by the current regulations for fuels. The ultrasound-assisted oxidative desulfurization (UAOD) process was applied to a petroleum product feedstock using dibenzothiophene as a model sulfur compound. The influence of ultrasonic irradiation time, oxidizing reagents amount, kind of solvent for the extraction step and kind of organic acid were investigated. The use of ultrasonic irradiation allowed higher efficiency for sulfur removal in comparison to experiments performed without its application, under the same reactional conditions. Using the optimized conditions for UAOD, the sulfur removal was about 95% after 9min of ultrasonic irradiation (20kHz, 750W, run at 40%), using hydrogen peroxide and acetic acid, followed by extraction with methanol.

  19. The role of inorganic phosphate in intact human erythrocytes

    International Nuclear Information System (INIS)

    Nishiguchi, Eiko; Umeda, Masahiro.

    1988-01-01

    The role of inorganic phosphate in intact human erythrocytes was investigated by phosphorus-31 nuclear magnetic resonance ( 31 P NMR). When erythrocytes stored for 5 weeks were incubated at 37 deg C, pH 7.4, in medium containing 2 mM adenine and 10 mM inosine, with or without 5 mM glucose, a substance of around 4 ppm, as assessed by 31 P NMR chemical shift, was detected in the mixture. However, this substance disappeared by the addition of inorganic phosphate. When erythrocytes stored for 4 weeks in acid citrate dextrose (ACD) solution were incubated with 2 mM adenine, 10 mM inosine, 5 mM glucose, 50 mM inorganic phosphate and 10 mM pyruvate at 37 deg C, pH 7.4, the 2,3-DPG level increased gradually, whereas the ATP level initially increased and then decreased. Intracellular inorganic phosphate appeared to be used for the synthesis of ATP and 2,3-DPG during the first 30 min. of the reaction. These results suggests that the inorganic phosphate accelerates glycolysis by increasing the activity of glycolytic enzymes rather than its direct involvement in synthesizing organic phosphorus compounds in stored erythrocytes. The results also suggests that the reserve energy from ATP synthesis is not sufficient for the synthesis of 2,3-DPG. (author)

  20. Regulation of dsr genes encoding proteins responsible for the oxidation of stored sulfur in Allochromatium vinosum.

    Science.gov (United States)

    Grimm, Frauke; Dobler, Nadine; Dahl, Christiane

    2010-03-01

    Sulfur globules are formed as obligatory intermediates during the oxidation of reduced sulfur compounds in many environmentally important photo- and chemolithoautotrophic bacteria. It is well established that the so-called Dsr proteins are essential for the oxidation of zero-valent sulfur accumulated in the globules; however, hardly anything is known about the regulation of dsr gene expression. Here, we present a closer look at the regulation of the dsr genes in the phototrophic sulfur bacterium Allochromatium vinosum. The dsr genes are expressed in a reduced sulfur compound-dependent manner and neither sulfite, the product of the reverse-acting dissimilatory sulfite reductase DsrAB, nor the alternative electron donor malate inhibit the gene expression. Moreover, we show the oxidation of sulfur to sulfite to be the rate-limiting step in the oxidation of sulfur to sulfate as sulfate production starts concomitantly with the upregulation of the expression of the dsr genes. Real-time RT-PCR experiments suggest that the genes dsrC and dsrS are additionally expressed from secondary internal promoters, pointing to a special function of the encoded proteins. Earlier structural analyses indicated the presence of a helix-turn-helix (HTH)-like motif in DsrC. We therefore assessed the DNA-binding capability of the protein and provide evidence for a possible regulatory function of DsrC.

  1. Optimization of low sulfur jerusalem artichoke juice for fossil fuels biodesulfurization process

    OpenAIRE

    Silva, Tiago P.; Paixão, Susana M.; Roseiro, J. Carlos; Alves, Luís Manuel

    2013-01-01

    Most of the world’s energy is generated from the burning of fossil fuels such as oil and its derivatives. When burnt, these fuels release into the atmosphere volatile organic compounds, sulfur as sulfur dioxide (SO2) and the fine particulate matter of metal sulfates. These are pollutants which can be responsible for bronchial irritation, asthma attacks, cardio-pulmonary diseases and lung cancer mortality, and they also contribute for the occurrence of acid rains and the increase of the hole i...

  2. Solubility and stability of inorganic carbonates

    International Nuclear Information System (INIS)

    Taylor, P.

    1987-01-01

    The chemistry of inorganic carbonates is reviewed, with emphasis on solubility and hydrolytic stability, in order to identify candidate waste forms for immobilization and disposal of 14 C. At present, CaCO 3 and BaCO 3 are the two most widely favoured wasted forms, primarily because they are the products of proven CO 2 -scrubbing technology. However, they have relatively high solubilities in non-alkaline solutions, necessitating care in selecting and assessing an appropriate disposal environment. Three compounds with better solubility characteristics in near-neutral waters are identified: bismutite, (BiO) 2 CO 3 ; hydrocerussite, Pb 3 (OH) 2 (CO 3 ) 2 ; and rhodochrosite, MnCO 3 . Some of the limitations of each of these alternative waste forms are discussed

  3. Mechanisms of inorganic and organometallic reactions

    CERN Document Server

    The purpose of this series is to provide a continuing critical review of the literature concerned with mechanistic aspects of inorganic and organo­ metallic reactions in solution, with coverage being complete in each volume. The papers discussed are selected on the basis of relevance to the elucidation of reaction mechanisms and many include results of a nonkinetic nature when useful mechanistic information can be deduced. The period of literature covered by this volume is July 1982 through December 1983, and in some instances papers not available for inclusion in the previous volume are also included. Numerical results are usually reported in the units used by the original authors, except where data from different papers are com­ pared and conversion to common units is necessary. As in previous volumes material included covers the major areas of redox processes, reactions of the nonmetallic elements, reaction of inert and labile metal complexes and the reactions of organometallic compounds. While m...

  4. Spheroidization of inorganic compounds by the LPPS method

    Czech Academy of Sciences Publication Activity Database

    Mastný, L.; Brožek, Vlastimil; Medřický, Jan; Marek, I.

    2017-01-01

    Roč. 13, č. 1 (2017), s. 162 ISSN 1336-7242. [Zjazd chemikov /69./. 11.09.2017-15.09.2017, Vysoké Tatry, Starý Smokovec] R&D Projects: GA ČR GA15-12145S Institutional support: RVO:61389021 Keywords : Water stabilized plasma * Liquid precursor plasma spraying * nanoparticles * spheroidization Subject RIV: BL - Plasma and Gas Discharge Physics OBOR OECD: Fluids and plasma physics (including surface physics)

  5. Oxidation of inorganic compounds of sulphur by various sulphur bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Parker, C D; Prisk, J

    1953-01-01

    Cultures of thiobacillus thiooxidans, Th. thioparus, Th. novellus, Thiobacillus b strains t and kand Th. concretivorus, Thiobacillus x and the m strains, organisms isolated from concrete were examined to elucidate the mode of oxidation and to establish the identity of the organisms recently isolated from corroded concrete. Thiosulphate was oxidized by all these bacteria. Th. thiooxidans, Th. concretivorus and Thiobacillus x first converted it to tetrathionate and sulphate and then oxidized the tetrathionate to sulphate and free sulphuric acid. Thiobaciullus x differed from the other two in that, owing to a lesser acid tolerance, some tetrathionate was found in the final products of oxidation. Th. Thioparus converted thiosulphate to sulphate and sulphur, followed by partial oxidation of the sulphur to sulphuric acid. Th. novellus produced sulphate and sulphuric acid. Thiobacillus b, the t and k strains and the m strains formed sulphate and tetrathionate with temporary increase in pH value; only Thiobacillus x oxidized tetrationate, yielding sulphate and sulphuric acid. Elementary sulphur was oxidized by Th. thiooxidans, th. Concretivorus, thiobacillus x and Th. thioparus; the rates of oxidation decreased in that order, and the only product was sulphuric acid. Hydrogen sulphide was oxidized only at low concentrations and only by th. Concretivorus and Thiobacillus x; sulphuric acid was the end-product, and elementary sulphur may have been an intermediate. Thiobacillus x differed from Th. thiooxidans in pH range for growth and from Th. thioparus in its method of oxidation of thiosulphate, tetrathionate and H/sub 2/S. The m strains were similar to thiobacillus b and the t and k strains of trautwein.

  6. Study on the concentrations of inorganic compounds in office spaces

    Directory of Open Access Journals (Sweden)

    Alina DIMA

    2014-12-01

    Full Text Available Indoor environment affects equally the health, the productivity and the occupants comfort, the costs for employers, owners of the buildings and the society being significantly larger, in the case of an inadequate interior ambient. Therefore, a good indoor air, in the office spaces, leads to the improvement of the work performance and to the decreasing of the absenteeism. Moreover, the occupants of discomfortable spaces will have the tendency to react in order to reduce their own discomfort, with consequences on the energy consumption.

  7. Copper inorganic-organic hybrid coordination compound as a novel ...

    Indian Academy of Sciences (India)

    fascinating supramolecular architecture. Electrochemical ... hybrid materials attract great attention in the fields of crystal ... erful potential applications in various areas, such as nonlinear ... Transition metal elements of ruthenium, iron, plat- inum ...

  8. Synthesis of sulfur-containing lubricant additives on the basis of fatty acid ethyl esters

    Directory of Open Access Journals (Sweden)

    Iurii S. Bodachivskyi

    2016-12-01

    Full Text Available The study reveals an energy-, resource- and eco-friendly method for preparation of sulfur-containing lubricant additives via interaction of fatty acid ethyl esters of rapeseed oil with elemental sulfur. The structure of synthesized compounds under various reactants ratio (5–50 wt.% of sulfur, duration (30–240 min and temperature of the process (160–215°С was investigated using various analytical techniques. According to the established data, aside from addition to double bonds, the side reaction of hydrogen substitution at α-methylene groups near these bonds occurs and induces the formation of conjugated systems and chromophoric sulfur-rich derivatives. Also, we found that increase of process duration evokes growth of polysulfane chains, in contrast to the raise of temperature, which leads to the formation of sulfur-containing heterocycles and hydrogen sulfide, as a result of elimination. Influence of accelerators on sulfurization of fatty acid ethyl esters was also examined. The most effective among them are mixtures of zinc dibutyldithiocarbamate with zinc oxide or stearic acid, which soften synthesis conditions and doubly decrease duration of the high-temperature stage. In addition, sulfur-containing compositions of ethyl esters and α-olefins, vulcanized esters by benzoyl peroxide, nonylphenols and zinc dinonylphenyldithiophosphate were designed. The study identified that lithium lubricant with sulfurized vulcanized esters provides improved tribological properties, in comparison with base lubricant or lubricant with the non-modified product.

  9. A multi-electron redox mediator for redox-targeting lithium-sulfur flow batteries

    Science.gov (United States)

    Li, Guochun; Yang, Liuqing; Jiang, Xi; Zhang, Tianran; Lin, Haibin; Yao, Qiaofeng; Lee, Jim Yang

    2018-02-01

    The lithium-sulfur flow battery (LSFB) is a new addition to the rechargeable lithium flow batteries (LFBs) where sulfur or a sulfur compound is used as the cathode material against the lithium anode. We report here our evaluation of an organic sulfide - dimethyl trisulfide (DMTS), as 1) a catholyte of a LFB and 2) a multi-electron redox mediator for discharging and charging a solid sulfur cathode without any conductive additives. The latter configuration is also known as the redox-targeting lithium-sulfur flow battery (RTLSFB). The LFB provides an initial discharge capacity of 131.5 mAh g-1DMTS (1.66 A h L-1), which decreases to 59 mAh g-1DMTS (0.75 A h L-1) after 40 cycles. The RTLSFB delivers a significantly higher application performance - initial discharge capacity of 1225.3 mAh g-1sulfur (3.83 A h L-1), for which 1030.9 mAh g-1sulfur (3.23 A h L-1) is still available after 40 cycles. The significant increase in the discharge and charge duration of the LFB after sulfur addition indicates that DMTS is better used as a redox mediator in a RTLSFB than as a catholyte in a LFB.

  10. Sulfur K-edge absorption spectroscopy on selected biological systems; Schwefel-K-Kanten-Absorptionsspektroskopie an ausgewaehlten biologischen Systemen

    Energy Technology Data Exchange (ETDEWEB)

    Lichtenberg, Henning

    2008-07-15

    Sulfur is an essential element in organisms. In this thesis investigations of sulfur compounds in selected biological systems by XANES (X-ray Absorption Near Edge Structure) spectroscopy are reported. XANES spectroscopy at the sulfur K-edge provides an excellent tool to gain information about the local environments of sulfur atoms in intact biological samples - no extraction processes are required. Spatially resolved measurements using a Kirkpatrick-Baez mirror focusing system were carried out to investigate the infection of wheat leaves by rust fungi. The results give information about changes in the sulfur metabolism of the host induced by the parasite and about the extension of the infection into visibly uninfected plant tissue. Furthermore, XANES spectra of microbial mats from sulfidic caves were measured. These mats are dominated by microbial groups involved in cycling sulfur. Additionally, the influence of sulfate deprivation and H{sub 2}S exposure on sulfur compounds in onion was investigated. To gain an insight into the thermal degradation of organic material the influence of roasting of sulfur compounds in coffee beans was studied. (orig.)

  11. Radiation effects on thermal decomposition of inorganic solids

    International Nuclear Information System (INIS)

    Dedgaonkar, V.G.

    1985-01-01

    Radiation effects on the thermal decomposition characteristics of inorganic oxyanions like permanganates, nitrates, zeolites and particularly ammonium perchlorate (AP) have been highlighted.The last compound finds wide application as an oxidizer in solid rocket propellents and although several hundred papers have been published on it during the last 30-40 years, most of which from the point of view of understanding and controlling the decomposition behaviour, there are only a few reports available in this area following the radiation treatment. (author)

  12. Tetrathionate and Elemental Sulfur Shape the Isotope Composition of Sulfate in Acid Mine Drainage

    Directory of Open Access Journals (Sweden)

    Nurgul Balci

    2017-08-01

    Full Text Available Sulfur compounds in intermediate valence states, for example elemental sulfur, thiosulfate, and tetrathionate, are important players in the biogeochemical sulfur cycle. However, key understanding about the pathways of oxidation involving mixed-valance state sulfur species is still missing. Here we report the sulfur and oxygen isotope fractionation effects during the oxidation of tetrathionate (S4O62− and elemental sulfur (S° to sulfate in bacterial cultures in acidic conditions. Oxidation of tetrathionate by Acidithiobacillus thiooxidans produced thiosulfate, elemental sulfur and sulfate. Up to 34% of the tetrathionate consumed by the bacteria could not be accounted for in sulfate or other intermediate-valence state sulfur species over the experiments. The oxidation of tetrathionate yielded sulfate that was initially enriched in 34S (ε34SSO4−S4O6 by +7.9‰, followed by a decrease to +1.4‰ over the experiment duration, with an average ε34SSO4−S4O6 of +3.5 ± 0.2‰ after a month of incubation. We attribute this significant sulfur isotope fractionation to enzymatic disproportionation reactions occurring during tetrathionate decomposition, and to the incomplete transformation of tetrathionate into sulfate. The oxygen isotope composition of sulfate (δ18OSO4 from the tetrathionate oxidation experiments indicate that 62% of the oxygen in the formed sulfate was derived from water. The remaining 38% of the oxygen was either inherited from the supplied tetrathionate, or supplied from dissolved atmospheric oxygen (O2. During the oxidation of elemental sulfur, the product sulfate became depleted in 34S between −1.8 and 0‰ relative to the elemental sulfur with an average for ε34SSO4−S0 of −0.9 ± 0.2‰ and all the oxygen atoms in the sulfate derived from water with an average normal oxygen isotope fractionation (ε18OSO4−H2O of −4.4‰. The differences observed in δ18OSO4 and the sulfur isotope composition of sulfate (δ34SSO4

  13. Determination of organic compounds in medicinal plants, commercialized in capsulated forms and 'in natura' by wavelength dispersive X-ray fluorescence spectrometry (WDXRF). Determination of quantitative inorganic profiles; Determinacao de componentes organicos em plantas medicinais, comercializadas em forma de po (capsulas) e 'in natura', utilizando a tecnica de fluorescencia de raios X por dispersao de comprimento de onda (WDXRF). Determinacao de perfis inorganicos quantitativos

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Manuel Octavio M.; Sato, Ivone Mulako; Salvador, Vera Lucia R. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil). Centro de Quimica e Meio Ambiente]. E-mail: lawless@usp.br

    2005-07-01

    X-ray fluorescence technique was used to determine major and trace elements for five Brazilian commercial medicinal plants. The bromobutane (Barbatimao), Ginkgo folium (Ginkgo biloba), Echinodorus macrophyllus (Chapeu de couro), Valeriana officinalis (Valeriana), Cordia salicifolia (Porangaba) samples were collected from three to six different commercial suppliers. The species were collected 'in natura' (leaves, flowers, barks and roots) and capsulated forms. The samples were grinded in liquid N{sub 2} atmosphere and double layer pressed pellet were prepared. The elements Na, Mg, P, S, Cl, K, Ca, Mn, Fe, Ni, Cu, Zn, Rb e Sr concentrations were determined by individual calibration curves. The precision and accuracy of method were evaluated by certified reference material, NIST 1547 - Peach Leaves and the Chauvenet, Cochrane, ANOVA and Z-score statistical tests were applied. Each specimen presented a distinct inorganic profile and a great variation in its composition was observed. The inorganic profile will contribute for the elaboration of a quality and security guide to assure the phytotherapics commercialization. Moreover, these profiles could be used as complementary data to active farmaco compounds profiles for specimen's ratification. (author)

  14. Dynamics of biogeochemical sulfur cycling in Mono Lake

    Science.gov (United States)

    Phillips, A. A.; Fairbanks, D.; Wells, M.; Fullerton, K. M.; Bao, R.; Johnson, H.; Speth, D. R.; Stamps, B. W.; Miller, L.; Sessions, A. L.

    2017-12-01

    Mono Lake, California is a closed-basin soda lake (pH 9.8) with high sulfate (120mM), and is an ideal natural laboratory for studying microbial sulfur cycling. Mono Lake is typically thermally stratified in summer while mixing completely in winter. However, large snowmelt inputs may induce salinity stratification that persists for up to five years, causing meromixis. During the California drought of 2014-16, the lake has mixed thoroughly each winter, but the abundant 2017 snowmelt may usher in a multi-year stratification. This natural experiment provides an opportunity to investigate the temporal relationship between microbial sulfur cycling and lake biogeochemistry. We analyzed water samples from five depths at two stations in May of 2017, before the onset of meromixis. Water column sulfate isotope values were generally constant with depth, centering at a δ34SVCDT of 17.39 ± 0.06‰. Organic sulfur isotopes were consistently lighter than lake sulfate, with a δ34SVCDT of 15.59 ± 0.56‰. This significant offset between organic and inorganic sulfur contradicts the minimal isotope effect associated with sulfate assimilation. Sediment push core organic values were further depleted, ranging between δ34SVCDT of -8.94‰ and +0.23‰, implying rapid turnover of Mono Lake sulfur pools. Both lipid biomarkers and 16S rRNA gene amplicons identify Picocystis salinarum, a unicellular green alga, as the dominant member of the microbial community. However, bacterial biomarkers and 16S rRNA genes point to microbes capable of sulfur cycling. We found that dsrA increased with depth (R2 = 0.9008, p reducers and sulfide oxidizers after >1 year of stratification. We saw no evidence in May of 2017 of sulfate reducing bacteria across the oxycline. Additionally, no sulfide was detectable in lake bottom waters despite oxygen below 6.25 µM. Preliminary results suggest a dynamic interplay between sulfide oxidation, sulfate reduction, and the onset of lake stratification. Additional

  15. Preparation of inorganic hydrophobic catalysts

    International Nuclear Information System (INIS)

    Yang, Yong; Wang, Heyi; Du, Yang

    2009-04-01

    In order to catalyse the oxidation of tritium gas, two inorganic hydrophobic catalysts are prepared. Under room temperature, the catalysed oxidation ratio of 0.3%-1% (V/V) hydrogen gas in air is higher than 95%. Pt-II inorganic hydrophobic catalysts has obviously better catalysing ability than Pt-PTFE and lower ability than Pt-SDB in H 2 -HTO isotopic exchange, because the pressure resistence of Pt-II is much higher than Pt-SDB, it can be used to the CECE cell of heavy water detritium system. (authors)

  16. Structure of rhenium (5) complexes with petroleum organic sulfur compounds

    International Nuclear Information System (INIS)

    Akhmadieva, R.G.; Yusupova, N.A.; Numanov, N.U.; Basitova, S.M.

    1985-01-01

    Structure of Re(5) complexes with petroleum sulfides (L) of ReOCl 3 (L) 2 composition is studied by the UV- and IR-spectroscopy method in a short-wave and long-wave ranges. It is shown that Re(5) complex with L are of the form of flattened octahedron,where three Cl atoms and one L molecule are arranged in the plane around Re atom. The structure is analogous to structure of Re complexes with synthetic cyclic sulfides

  17. Changes in the levels of major sulfur metabolites and free amino acids in pea cotyledons recovering from sulfur deficiency

    International Nuclear Information System (INIS)

    Macnicol, P.K.; Randall, P.J.

    1987-01-01

    Changes in levels of sulfur metabolites and free amino acids were followed in cotyledons of sulfur-deficient, developing pea seeds (Pisum sativum L.) for 24 hours after resupply of sulfate, during which time the legumin mRNA levels returned almost to normal. Two recovery situations were studied: cultured seeds, with sulfate added to the medium, and seeds attached to the intact plant, with sulfate added to the roots. In both situations the levels of cysteine, glutathione, and methionine rose rapidly, glutathione exhibiting an initial lag. In attached but not cultured seeds methionine markedly overshot the level normally found in sulfur-sufficient seeds. In the cultured seed S-adenosylmethionine (AdoMet), but not S-methylmethionine, showed a sustained rise; in the attached seed the changes were slight. The composition of the free amino acid pool did not change substantially in either recovery situation. In the cultured seed the large rise in AdoMet level occurred equally in nonrecovering seeds. It was accompanied by 6-fold and 10-fold increases in γ-aminobutyrate and alanine, respectively. These effects are attributed to wounding resulting from excision of the seed. 35 S-labeling experiments showed that there was no significant accumulation of label in unidentified sulfur-containing amino compounds in either recovery situation. It was concluded from these results and those of other workers that, at the present level of knowledge, the most probable candidate for a signal compound, eliciting recovery of legumin mRNA level in response to sulfur-feeding, is cysteine

  18. Inorganic Nanotubes and Fullerene-Like Nanoparticles:. from the Lab to the Market Place

    Science.gov (United States)

    Tenne, R.

    2013-05-01

    Layered compounds, like MoS2 were shown by the author to be unstable in the nano-regime. Using new chemical strategies, closed-cage hollow nanostructures in the form of inorganic fullerene-like nanoparticles and inorganic nanotubes were synthesized. These nanostructures exhibit numerous interesting physico-chemical properties and are employed as superior solid lubricants, with numerous other applications currently being developed.

  19. High-performance liquid ion-pair chromatography in inorganic analysis

    International Nuclear Information System (INIS)

    Alimarin, I.P.; Basova, E.M.; Bol'shova, T.A.; Ivanov, V.M.

    1990-01-01

    In literature review for the recent 15 years theoretical foundations, regularities and mechanisms of ionized compound retention in reverse-phase ion-pair chromatography are considered, possibilities and prospects of its application in inorganic analysis being demonstrated. Analytic characteristics of the methods for the determination of inorganic anions (I - , IO 3 - , MoO 4 2- , etc.), as well as metals (Zr, Hf, V, Nb, Mo, W, Ru, lanthanides, etc.) in the form of chelates, are given

  20. Inorganics in Organics: Tracking down the Intrinsic Equilibriums between Organic Molecules and Trace Elements in Oceanic Waters

    Science.gov (United States)

    Lechtenfeld, O. J.; Koch, B. P.; Kattner, G.

    2010-12-01

    Recent developments in analytical instrumentation enable to describe biogeochemical processes in oceanic waters on a molecular level. This is the prerequisite to integrate biological and geochemical parameters and to develop chemical cycles on a global perspective. The state-of-the-art Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) applications for dissolved organic matter (DOM) focus mainly on carbon, hydrogen, oxygen and nitrogen isotopes. Implementation of sulfur and especially phosphorus in the molecular formula assignment has been questionable because of ambiguous calculated elemental formulas. On the other hand, many compounds bearing these elements are well known to occur in the dissolved state as part of the permanent recycling processes (e.g. phospholipids, phosphonates) but analytics of dissolved organic phosphorus (DOP) and sulfur (DOS) are often hampered by the large inorganic P and S pools. Even less is known about complexation characteristics of the DOM moieties. Although electrochemical methods provide some information about trace metal speciation, the high amount of organic molecules and its insufficient description as chemical functional classes prevent the assignment of trace metals to ligand classes. Nevertheless, it is undoubtful that a varying but extensive amount of transition metals is bond in form of organic complexes. Hyphenation of reversed phase high performance liquid chromatography (RP-HPLC) with high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) is a valuable tool to study these metal-organic interactions in a qualitative and quantitative approach. We established a desolvation method that allows direct transfer of high organic solvent loads into the plasma. Thus, in combination with internal standardization and external calibration, the investigation of a broad polarity scale was possible. This approach overcomes previous restrictions to non-organic solvent separation techniques like size