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Sample records for antimony compounds

  1. Heteronuclear compounds of arsenic and antimony

    Science.gov (United States)

    Mauser, James E.

    1982-09-01

    Volatilization of secondary metals such as arsenic, antimony, and bismuth, during the smelting of copper ores, is important because of environmental and resource considerations. The Bureau of Mines, United States Department of the Interior, has been studying copper concentrate roasting in conjunction with the volatility of these minor constituents. Some unusual vaporization behavior initiated this supplemental paper which shows that when the mixed sulfides of arsenic and antimony are heated, the volatilization of arsenic is retarded and the volatilization of antimony increased. Mixed oxides of arsenic and antimony also exhibit exceptional volatilization behavior. These anomalous vaporization behaviors are attributed to the formation of heteronuclear compounds of arsenic and antimony, but the colligative properties of solutions may also be a factor.

  2. Antimony

    Science.gov (United States)

    Seal, Robert R.; Schulz, Klaus J.; DeYoung,, John H.; Sutphin, David M.; Drew, Lawrence J.; Carlin, James F.; Berger, Byron R.; Schulz, Klaus J.; DeYoung,, John H.; Seal, Robert R.; Bradley, Dwight C.

    2017-12-19

    Antimony is an important mineral commodity used widely in modern industrialized societies. The element imparts strength, hardness, and corrosion resistance to alloys that are used in many areas of industry, including in lead-acid storage batteries. Antimony’s leading use is as a fire retardant in safety equipment and in household goods, such as mattresses. The U.S. Government has considered antimony to be a critical mineral mainly because of its use in military applications. The great majority of the world’s antimony comes from China, and much of the remainder is shipped to China for smelting. Antimony resources are unevenly distributed around the world. China has the bulk of the world’s identified resources; other countries that have identified antimony resources include Bolivia, Canada, Mexico, Russia, South Africa, Tajikistan, and Turkey. Resources in the United States are located mainly in Alaska, Idaho, Montana, and Nevada. The most significant antimony mineral deposits occur in geologic environments with a thick sequence of siliciclastic sedimentary rocks in areas with significant fault and fracture systems. The most common antimony ore mineral is stibnite (Sb2 S3 ), but more than 100 other minerals also contain antimony. The presence of antimony in surface waters and groundwaters results primarily from rock weathering, soil runoff, and anthropogenic sources. Global emissions of antimony to the atmosphere average 6,100 metric tons per year. Empirical data suggest that the acid-generating potential of antimony mine waste is low.

  3. Fluoride and oxyfluoride compounds and niobium, antimony and tellurium

    International Nuclear Information System (INIS)

    Corbin, Odile.

    1982-02-01

    This paper is a detailed bibliographic report on fluoride and oxyfluoride compounds and niobium, antimony and tellurium oxides. Compounds identified to date are: NbF 3 , NbF 4 , NbF 5 , NbF 6 , NbO 2 F, NbOF 3 , Nb 3 O 7 F, SbF 3 , SbF 5 , SbOF, SbOF 3 , SbO 2 F, Sb 2 O 3 , Sb 2 O 4 , TeF 4 , Te 2 F 10 , TeF 6 , Te 2 OF 10 , Te 3 O 2 F 14 , Te 6 F 26 O 5 , TeO, TeO 2 , TeO 3 . Synthesis processes, physical properties and chemical properties are given for each of the above compounds [fr

  4. Varicella zoster virus reactivation during or immediately following treatment of tegumentary leishmaniasis with antimony compounds

    Directory of Open Access Journals (Sweden)

    Andrea Barbieri Barros

    2014-07-01

    Full Text Available Antimony compounds are the cornerstone treatments for tegumentary leishmaniasis. The reactivation of herpes virus is a side effect described in few reports. We conducted an observational study to describe the incidence of herpes zoster reactivation during treatment with antimony compounds. The global incidence of herpes zoster is approximately 2.5 cases per 1,000 persons per month (or 30 cases per 1,000 persons per year. The estimated incidence of herpes zoster in patients undergoing antimony therapy is higher than previously reported.

  5. Antimony: a flame fighter

    Science.gov (United States)

    Wintzer, Niki E.; Guberman, David E.

    2015-01-01

    Antimony is a brittle, silvery-white semimetal that conducts heat poorly. The chemical compound antimony trioxide (Sb2O3) is widely used in plastics, rubbers, paints, and textiles, including industrial safety suits and some children’s clothing, to make them resistant to the spread of flames. Also, sodium antimonate (NaSbO3) is used during manufacturing of high-quality glass, which is found in cellular phones.

  6. The cytotoxicity of organobismuth compounds with certain molecular structures can be diminished by replacing the bismuth atom with an antimony atom in the molecules.

    Science.gov (United States)

    Kohri, Kumiko; Yoshida, Eiko; Yasuike, Shuji; Fujie, Tomoya; Yamamoto, Chika; Kaji, Toshiyuki

    2015-06-01

    Organic-inorganic hybrid molecules, which are composed of an organic structure and metal(s), are indispensable for synthetic chemical reactions; however, their toxicity has been incompletely understood. In the present study, we discovered two cytotoxic organobismuth compounds whose cytotoxicity diminished upon replacement of the intramolecular bismuth atom with an antimony atom. The intracellular accumulation of the organobismuth compounds was much higher than that of the organoantimony compounds with the corresponding organic structures. We also showed that both the organic structure and bismuth atom are required for certain organobismuth compounds to exert their cytotoxic effect, suggesting that the cytotoxicity of such a compound is a result of an interaction between the organic structure and the bismuth atom. The present data suggest that organobismuth compounds with certain molecular structures exhibit cytotoxicity via an interaction between the molecular structure and the bismuth atom, and this cytotoxicity can be diminished by replacing the bismuth atom with an antimony atom, resulting in lower intracellular accumulation.

  7. Solvent extraction of indium, tin, arsenic, and antimony by non-phosphorous compounds

    International Nuclear Information System (INIS)

    Auchapt, J.M.; Tostain, Jacqueline.

    1975-12-01

    The extraction methods of In, Ti, Sn, As and Sb using non-phosphorous compounds are reviewed. This report is the continuation of the BIB-212 (pt.1) report concerned by Zn, Cd, Pb and Ag. So, the main elements of Zn ores are studied in these two reports [fr

  8. Selective extraction of traffic-related antimony compounds for speciation analysis by graphite furnace atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Zih-Perenyi, K., E-mail: perkat@freestart.h [L. Eoetvoes University, Institute of Chemistry, H-1518 Budapest 112, P.O. Box 32. (Hungary); Neurohr, K., E-mail: kata.neurohr@gmail.co [L. Eoetvoes University, Institute of Chemistry, H-1518 Budapest 112, P.O. Box 32. (Hungary); Nagy, G. [Semmelweis University, Faculty of Pharmacy, H-1085 Budapest, Ulloi Str. 26. (Hungary); Balla, M., E-mail: balla@reakt.bme.h [Budapest University of Technology and Economics, Institute of Nuclear Techniques, H-1111 Budapest, Muegyetem rakpart 9 (Hungary); Lasztity, A., E-mail: alasztity@gmail.co [L. Eoetvoes University, Institute of Chemistry, H-1518 Budapest 112, P.O. Box 32. (Hungary)

    2010-09-15

    Most traffic-related antimony air pollutants are derived from brake dust. Brake dust contains Sb{sub 2}S{sub 3}, used as a friction material in brake pads, and its high-temperature oxidation products, Sb{sub 2}O{sub 3} or Sb{sub 2}O{sub 4}. Systematic investigations were carried out to find the most selective leaching conditions for these substances. First, solubility experiments of the pure potential compounds mentioned above were carried out. Then, the leaching of these compounds from home-made artificial dusts previously spiked with these compounds at the trace level was investigated. A 0.5 mol L{sup -1} citric acid solution proved to leach the whole Sb{sub 2}O{sub 3} content while extracting less than 10% Sb{sub 2}S{sub 3} and no Sb{sub 2}O{sub 4} at all. It was found that Sb{sub 2}O{sub 3} and Sb{sub 2}S{sub 3} traces were soluble in a 6 mol L{sup -1} HCl solution, quantitatively and selectively. Graphite furnace atomic absorption spectrometry and hydride generation graphite furnace atomic absorption spectrometry methods were developed to determine the Sb content of the extracts. The proposed method proved to be applicable to settled dust containing traffic-related Sb compounds. The detection limits were 1.2 and 0.3 {mu}g g{sup -1} for leaching by citric acid and HCl solution, respectively, which were adequate for Sb content determination in the urban dust studied. The reproducibility of the method expressed as relative standard deviation was about 7%. The results showed that the concentration of leachable Sb was 40 {mu}g g{sup -1} in the settled dust of Budapest, about half of which corresponded to Sb{sub 2}O{sub 3}. The Sb{sub 2}O{sub 4} content calculated as the difference of total and leachable fraction was about 10% with high uncertainty.

  9. Synthesis, characterization and electrochemical performances of new antimony-containing graphite compounds used as anodes for lithium-ion batteries

    International Nuclear Information System (INIS)

    Dailly, A.; Willmann, P.; Billaud, D.

    2002-01-01

    Graphite intercalation intercalated with metal alloys able to alloy reversibly lithium constitute a large set of new anodic materials for lithium-ion batteries of significantly improved reversible capacities. Especially, graphite intercalated with cesium-antimony alloys can be used as materials for anodes in lithium-ion batteries. Electrochemical insertion of lithium in such chemically modified precursors shows that lithium both intercalates in the empty van der Waals spaces of graphite and alloys reversibly with antimony. The total electrochemical reversible capacities, measured between 0 and 2 V vs Li + /Li, close to 700 mAh g -1 have been currently obtained

  10. In vitro antileishmanial properties of neutron-irradiated meglumine antimoniate

    Energy Technology Data Exchange (ETDEWEB)

    Borborema, Samanta Etel Treiger; Nascimento, Nanci do [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), SP (Brazil). Lab. de Biologia Molecular]. E-mail: samanta@usp.br; Osso Junior, Joao Alberto [Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), SP (Brazil). Centro de Radiofarmacia]. E-mail: jaosso@ipen.br; Andrade Junior, Heitor Franco de [Instituto de Medicina Tropical de Sao Paulo (IMT-SP), SP (Brazil). Lab. de Protozoologia]. E-mail:hfandrad@usp.br

    2005-10-15

    Pentavalent antimony, as meglumine antimoniate (Glucantime) or sodium stibogluconate (Pentostam), is the main treatment for leishmaniasis, a complex of diseases caused by the protozoan Leishmania, and an endemic and neglected threat in Brazil. Despite over half a century of clinical use, their mechanism of action, toxicity and pharmacokinetic data remain unknown. The analytical methods for determination of antimony in biological systems remain complex and have low sensitivity. Radiotracer studies have a potential in pharmaceutical development. The aim of this study was to obtain a radiotracer for antimony, with suitable physical and biological properties. Meglumine antimoniate was neutron irradiated inside the IEA-R1 nuclear reactor, producing two radioisotopes {sup 122} Sb and {sup 124} Sb, with high radionuclidic purity and good specific activity. This compound showed the same antileishmanial activity as the native compound. The use of the radiotracers, easily created by neutron irradiation, could be an interesting tool to solve important questions in antimonial pharmacology. (author)

  11. Progress report on neutron beam experiments in Thailand: effects of antimony substitutions on the critical temperature of Bi-Pb-Sr-Ca-Cu-O compounds

    Energy Technology Data Exchange (ETDEWEB)

    Sangariyavanich, A.; Ampornrat, P. [Office of Atomic Energy for Peace, Bangkok (Thailand)

    1998-10-01

    Effects of systematic substitutions of antimony for bismuth in Bi{sub 1.8-x}Pb{sub 0.2}Sb{sub x}Sr{sub 2}Ca{sub 3}Cu{sub 4}O{sub 10} have been investigated. Fabrication of the specimens has been performed by solid state reaction in air. The samples were sintered between 820degC - 843degC for 65 hours and subsequently quenched in liquid nitrogen. The critical temperatures of most specimens as determined by standard four-probe technique was higher than 100 K. Phase identification by X-ray diffraction technique indicated that `2223` and `2234` were the predominant phases in these samples. (author)

  12. Synthesis and characterization of nanometer sized thermoelectric lead-antimony-silver-tellurium compounds and related materials; Synthese und Charakterisierung nanoskaliger Thermoelektrika der LAST (Lead-Antimony-Silver-Tellurium)-Familie und verwandter Verbindungen

    Energy Technology Data Exchange (ETDEWEB)

    Petri, Denis

    2012-09-10

    The present dissertation deals with different variants of synthesis and processing of nanocrystalline composites of various thermoelectric compounds based on lead telluride including LAST-m (AgPb{sub m}SbTe{sub m+2}), LASTT-m-x (AgPb{sub m-x}Sn{sub x}SbTe{sub m+2}), LABST-m-x (AgPb{sub m}Sb{sub 1-x}Bi{sub x}Te{sub m+2}), doped LAST-m and (PbTe){sub m}(M{sup 15}{sub 2}Te{sub 3}) and the characterization thereof. A new route of manufacturing nanocrystalline composites was developed. The so called co-ball milling-route includes the synthesis of bi- or multinary compounds by conventional solid state melting methods followed by combined milling of appropriate amounts in a planetary ball mill; a process related to the widely used mechanical alloying of elemental powders. The as produced powders were shortly annealed for one hour and a.erwards compacted either at room temperature followed by pressureless sintering or combined application of high pressure and elevated temperatures via spark-plasma-sintering or short-term-sintering. The ball milling yielded micron-sized agglomerates consisting of crystallites with diameters ranging from 10 to 50 nm. These crystallites exhibited complicated internal nanostructures severe crystal defects as a consequence of the high energy processing. During short-term annealing some grain coarsening occured and the crystal defects partly healed, which was confirmed by TEM and HRTEM investigations as well as profile analysis of XRD powder pattern. Local EDX-analysis showed different compositions at every point as a consequence of synthesis and decomposition of the compounds. Measurements of thermopower, electrical and thermal conductivity were carried out and the values of the figure of merit ZT and the powerfactor were calculated. In general the compounds exhibited larger thermopower than corresponding bulk materials, which might be attributed to energy filtering of charge carriers at partly oxidized grain boundaries. Due to enhanced phonon

  13. Antimony(V) and Bismuth(V) Complexes of Lapachol: Synthesis, Crystal Structure and Cytotoxic Activity

    OpenAIRE

    Cynthia Demicheli; Carlos A. de Simone; Frédéric Frézard; Eufrânio N. da Silva Júnior; Cláudio L. Donnici; Elene C. Pereira-Maia; Ludmila G. de Oliveira; Meiriane M. Silva; Flávia C. S. de Paula

    2011-01-01

    Antimony(V) and bismuth(V) complexes of lapachol have been synthesized by the reaction of Ph3SbCl2 or Ph3BiCl2 with lapachol (Lp) and characterized by several physicochemical techniques such as IR, and NMR spectroscopy and X-ray crystallography. The compounds contain six-coordinated antimony and bismuth atoms. The antimony(V) complex is a monomeric derivative, (Lp)(Ph3Sb)OH, and the bismuth(V) complex is a dinuclear compound bridged by an oxygen atom, (Lp)2(Ph3Bi)2O. Both compounds inhibited ...

  14. Behaviour of antimony during thermal treatment of Sb-rich halogenated waste

    Energy Technology Data Exchange (ETDEWEB)

    Klein, J. [Laboratoire Gestion des Risques et Environnement, 25 rue de Chemnitz, 68200 Mulhouse (France); Dorge, S., E-mail: sophie.dorge@uha.fr [Laboratoire Gestion des Risques et Environnement, 25 rue de Chemnitz, 68200 Mulhouse (France); Trouve, G. [Laboratoire Gestion des Risques et Environnement, 25 rue de Chemnitz, 68200 Mulhouse (France); Venditti, D.; Durecu, S. [TREDI Departement de Recherche, Technopole de Nancy-Brabois, 9 avenue de la Foret de Haye, BP 184, 54505 Vandoeuvre-les-Nancy (France)

    2009-07-30

    Antimony compounds have a wide range of industrial applications, particularly as additives in flame retardants. To ensure environmentally friendly waste incineration of Sb-rich wastes, it is essential to strengthen the knowledge about the fate of antimony and the potential formation of harmful species. Investigations should be conducted particularly in relation with the main operational parameters controlling the process, chiefly temperature, residence time and air supply in the oven and in the post-combustion zone, prior final adapted cleaning of the flue-gas stream. Experimental studies focusing on antimony behaviour were undertaken through laboratory-scale thermal treatment at 850 deg. C and 1100 deg. C of a Sb-rich halogenated waste, originating from the sector of flame retardants formulation. The configuration of our laboratory experimental device allowed to achieve only low oxidative conditions in the waste bed, but high oxidative strength coupled with high temperature and sufficient gas residence time in the post-combustion zone, as prescribed during the incineration of hazardous wastes. Atomic absorption spectroscopy was used to assess the partition of antimony in the different compartments of the process. The oxidation degree of antimony in the gas-phase was determined by the use of electrochemical techniques, namely polarography coupled with anodic stripping voltamperometry. The partition of antimony between the residual ash and the gas-phase under moderate oxidative conditions in the waste bed was constant, whatever the temperature: the volatilization rate for antimony was {approx}64%, while a {approx}36% fraction remained in the residual bottom ashes. But interestingly, while at 850 {sup o}C, antimony was mainly present in the gas-phase at a +III oxidation degree, an increase in temperature of 250 {sup o}C favoured the presence of antimony to its highest oxidation degree +V in the flue-gas stream, a valence known to be involved in less toxic species.

  15. In Vitro antileishmanial properties of neutron-irradiated meglumine antimoniate

    Directory of Open Access Journals (Sweden)

    Samanta Etel Treiger Borborema

    2005-10-01

    Full Text Available Pentavalent antimony, as meglumine antimoniate (Glucantime® or sodium stibogluconate (Pentostam® , is the main treatment for leishmaniasis, a complex of diseases caused by the protozoan Leishmania, and an endemic and neglected threat in Brazil. Despite over half a century of clinical use, their mechanism of action, toxicity and pharmacokinetic data remain unknown. The analytical methods for determination of antimony in biological systems remain complex and have low sensitivity. Radiotracer studies have a potential in pharmaceutical development. The aim of this study was to obtain a radiotracer for antimony, with suitable physical and biological properties. Meglumine antimoniate was neutron irradiated inside the IEA-R1 nuclear reactor, producing two radioisotopes 122Sb and 124Sb, with high radionuclidic purity and good specific activity. This compound showed the same antileishmanial activity as the native compound. The use of the radiotracers, easily created by neutron irradiation, could be an interesting tool to solve important questions in antimonial pharmacology.Os antimoniais pentavalentes, como o antimoniato de meglumina (Glucantime® ou estibogluconato de sódio (Pentostam® , são o principal tratamento para a leishmaniose, um complexo de doenças causadas pelo protozoário parasita Leishmania, uma doença endêmica e negligenciada no Brasil. Apesar do seu uso clínico por mais de meio século, seu mecanismo de ação, toxicidade e dados de farmacocinética permanecem desconhecidos. Os métodos analíticos para determinação de antimônio em sistemas biológicos são complexos e apresentam baixa sensibilidade. Estudos utilizando radiotraçadores têm papel potencial no desenvolvimento farmacológico. O objetivo deste estudo foi desenvolver um radiotraçador de antimônio, com propriedades físicas e biológicas adequadas. O antimoniato de meglumina foi irradiado por nêutrons no reator nuclear IEA-R1, produzindo dois radioisótopos: 122

  16. Antimony(V) and bismuth(V) complexes of lapachol: synthesis, crystal structure and cytotoxic activity.

    Science.gov (United States)

    Oliveira, Ludmila G de; Silva, Meiriane M; Paula, Flávia C S de; Pereira-Maia, Elene C; Donnici, Cláudio L; Simone, Carlos A de; Frézard, Frédéric; Silva, Eufrânio N da; Demicheli, Cynthia

    2011-12-13

    Antimony(V) and bismuth(V) complexes of lapachol have been synthesized by the reaction of Ph₃SbCl₂ or Ph₃BiCl₂ with lapachol (Lp) and characterized by several physicochemical techniques such as IR, and NMR spectroscopy and X-ray crystallography. The compounds contain six-coordinated antimony and bismuth atoms. The antimony(V) complex is a monomeric derivative, (Lp)(Ph₃Sb)OH, and the bismuth(V) complex is a dinuclear compound bridged by an oxygen atom, (Lp)₂(Ph₃Bi)₂O. Both compounds inhibited the growth of a chronic myelogenous leukemia cell line and the complex of Bi(V) was about five times more active than free lapachol. This work provides a rare example of an organo-Bi(V) complex showing significant cytotoxic activity.

  17. Antimony(V and Bismuth(V Complexes of Lapachol: Synthesis, Crystal Structure and Cytotoxic Activity

    Directory of Open Access Journals (Sweden)

    Cynthia Demicheli

    2011-12-01

    Full Text Available Antimony(V and bismuth(V complexes of lapachol have been synthesized by the reaction of Ph3SbCl2 or Ph3BiCl2 with lapachol (Lp and characterized by several physicochemical techniques such as IR, and NMR spectroscopy and X-ray crystallography. The compounds contain six-coordinated antimony and bismuth atoms. The antimony(V complex is a monomeric derivative, (Lp(Ph3SbOH, and the bismuth(V complex is a dinuclear compound bridged by an oxygen atom, (Lp2(Ph3Bi2O. Both compounds inhibited the growth of a chronic myelogenous leukemia cell line and the complex of Bi(V was about five times more active than free lapachol. This work provides a rare example of an organo-Bi(V complex showing significant cytotoxic activity.

  18. Mineral resource of the month: antimony

    Science.gov (United States)

    ,

    2008-01-01

    The article describes the characteristics and industrial uses of antimony. Antimony, which is produced as a byproduct of mining other metals such as gold, lead or silver, is used in everything from flame retardants, batteries, ceramics and glass. It is also used in glass for television picture tubes, computer monitors, pigments and catalysts.

  19. Surface complexation of antimony on kaolinite.

    Science.gov (United States)

    Rakshit, Sudipta; Sarkar, Dibyendu; Datta, Rupali

    2015-01-01

    Geochemical fate of antimony (Sb) - a similar oxyanion as arsenic (As) - in a variety of environment is largely unexplored. Kaolinite is an important, naturally occurring clay mineral in soils and aquifers and is known to control the fate of several contaminants via a multitude of geochemical processes, primarily adsorption. Here we report adsorption of antimony on kaolinite as a function of solution chemistry: initial antimony concentration, pH, ionic strength, and a competing anion. A surface complexation modeling (SCM) approach was undertaken to understand the potential mechanistic implications of sorption envelope data. In the SCM, a multicomponent additive approach, in which kaolinite is assumed to be a (1:1) mixture of quartz (≡SiOH) and gibbsite (≡AlOH), was tested. Results indicated that ionic strength has a minimal effect on antimony adsorption. For the lower initial antimony concentration (4.11 μM), the additive model with binuclear surface complexes on quartz and gibbsite showed a better fit at pH3.5. However, the additive model with binuclear surface complex on quartz and mononuclear surface complex on gibbsite showed an excellent fit of the data. Phosphate greatly influenced antimony adsorption on kaolinite at both low and high antimony loadings, indicating competition for available surface sites. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Investigation into the reduction of antimony

    International Nuclear Information System (INIS)

    Hornibrook, C.

    1996-01-01

    This paper describes a program being implemented to decrease the antimony being released in waste water from the processing of liquid low-level radioactive wastes. The process being studied is the use of a crossflow membrane filter to remove antimony, and possibly cobalt 58. The process will evaluate the efficiency gains available from changing the oxidation states of the antimony with respect to the removal efficiency. Ion absorbers and ion exchange media will also be evaluated. The equipment is to be first tested on waste water from the November outage of Oconee, and then to use it on other radwaste processing studies

  1. FIRST REPORT ON OTOTOXICITY OF MEGLUMINE ANTIMONIATE

    Directory of Open Access Journals (Sweden)

    Cláudia Maria Valete-Rosalino

    2014-09-01

    Full Text Available Introduction: Pentavalent antimonials are the first drug of choice in the treatment of tegumentary leishmaniasis. Data on ototoxicity related with such drugs is scarcely available in literature, leading us to develop a study on cochleovestibular functions. Case Report: A case of a tegumentary leishmaniasis patient, a 78-year-old man who presented a substantial increase in auditory threshold with tinnitus and severe rotatory dizziness during the treatment with meglumine antimoniate, is reported. These symptoms worsened in two weeks after treatment was interrupted. Conclusion: Dizziness and tinnitus had already been related to meglumine antimoniate. However, this is the first well documented case of cochlear-vestibular toxicity related to meglumine antimoniate.

  2. Systemic Meglumine Antimoniate in Cutaneous Leishmaniasis of Children: Clinical and Laboratory Complications.

    Science.gov (United States)

    Layegh, Pouran; Khademi, Zeinab; Afzal Aghaee, Monavar; Moghiman, Toktam

    2015-12-01

    Children account for 7%-20% of cutaneous leishmaniasis cases in Iran, but there are few safety data to guide pediatric antiparasitic therapy. We evaluated the clinical and laboratory tolerance of the systemic pentavalent antimonial compound meglumine antimoniate, in 70 Iranian children with cutaneous leishmaniasis. Adverse effects were similar to those seen in adults. © The Author 2014. Published by Oxford University Press on behalf of the Pediatric Infectious Diseases Society. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  3. Sorption of antimony on human teeth

    International Nuclear Information System (INIS)

    Nofal, M.; Amin, H.; Alian, G.

    1997-01-01

    The study of the uptake of toxic elements on human teeth represents an interesting research area, as the fate of these elements when present in the human food is of health significance. Since antimony is one of the common toxic elements and since, the chemical behaviour of antimony is similar to that of arsenic, one of the most important toxic elements commonly encountered in cases of food poisoning, it has been decided to investigate its uptake on human teeth and on other restoration materials. The radioactive tracer technique was used to evaluate the concentration of antimony sorbed on teeth. This tracer was obtained by irradiation of antimony metal in the reactor, subsequent dissolution in concentrated sulphuric acid, evaporation to dryness and making the solution 6 M in Hydrochloric acid (1). Antimony prepared in this way is in the trivalent state (Sb III). Sorption was studied in water, tea, coffee, red tea and chicken soup. The highest sorption was achieved from water and chicken soup and least sorption was noticed in case of coffee. The results are presented in the form of the depletion of the radioactivity (A) of antimony with time in presence of a tooth in water and other drinks

  4. Extraction of antimony and arsenic from sulphidic concentrates

    Directory of Open Access Journals (Sweden)

    BalហPeter

    2000-09-01

    Full Text Available The efficiency of both mineral processing and extractive metallurgy of minerals depends on the separation of individual mineral components and on the exposure of their surface. The production of flotation concentrates, with particle sizes of tens of microns, is not sufficient for many hydrometallurgical processes to operate at their optimum. As a consequence, metallurgical plants require for the effective processing high temperatures and pressures and some sort of concentrate pretreatment. Mechanical activation is an innovative procedure where an improvement in hydrometallurgical processes can be attained via a combination of new surface area and formation of crystalline defects in minerals. The lowering of reaction temperatures, the increase of rate and amount of solubility, preparation of water soluble compounds, the necessity for simpler and less expensive reactors and shorter reaction times are some of the advantages of mechanical activation. The environmental aspects of these processes are particularly attractive.This paper is devoted to the examples of application of mechanochemical treatment in the processing of sulfidic concentrates. The sulphide concentrates of various origin (Peru, Chile, Slovakia were succesfully tested for antimony and arsenic extraction. The mechanochemical treatment improve the degree of recovery and the rate of leaching of both metals. Two modes of mechanochemical treatment were tested: the mechanical activation before leaching and the mechanochemical leaching which integrates mechanical activation and leaching into a common step. The flowsheet consisted of mechanochemical leaching in an attritor and further operations as filtration, cementation, antimony precipitation, crystallization and arsenic precipitation. The pilot plant unit was designed for 500 kg per day feed of tetrahedrite concentrate. For the antimony extraction, electrowinning has also been considered. The residue which is a CuAgAu concentrate was

  5. Synthesis, characterization and single crystal X-ray analysis of chlorobis(N,N-dimethyldithiocarbamato-S,S′antimony(III

    Directory of Open Access Journals (Sweden)

    H.P.S. Chauhan

    2015-07-01

    Full Text Available The title compound chlorobis(N,N-dimethyldithiocarbamato-S,S′antimony(III has been prepared in distilled acetonitrile and characterized by physicochemical [melting point and molecular weight determination, elemental analysis (C, H, N, S & Sb], spectral [FT–IR, far IR, NMR (1H & 13C] studies. The crystal and molecular structure was further confirmed using single crystal X-ray diffraction analysis which features a five-coordinate geometry for antimony(III within a ClS4 donor set. The distortion in the co-planarity of ClSbS3 evidences the stereochemical influence exerts by the lone pair of electrons on antimony(III. Two centrosymmetrically related molecule held together via C–H···Cl secondary interaction result in molecular aggregation of the compound.

  6. Chlorination of antimony and its volatilization treatment of waste antimony-uranium composite oxide catalyst

    International Nuclear Information System (INIS)

    Sawada, K.; Enokida, Y.

    2011-01-01

    For the waste antimony-uranium composite oxide catalyst, the chlorination of antimony and its volatilization treatment were proposed, and evaluated using hydrogen chloride gas at 873-1173 K. During the treatment, the weight loss of the composite oxide sample, which resulted from the volatilization of antimony, was confirmed. An X-ray diffraction analysis showed that uranium oxide, U 3 O 8 , was formed during the reaction. After the treatment at 1173 K for 1 h, almost all the uranium contained in the waste catalyst was dissolved by a 3 M nitric acid solution at 353 K within 10 min, although that of the non-treated catalyst was less than 0.1%. It was found that the chlorination and volatilization treatment was effective to separate antimony from the composite oxide catalyst and change uranium into its removable form. (orig.)

  7. Microbial antimony biogeochemistry: Enzymes, regulation, and related metabolic pathways

    Science.gov (United States)

    Li, Jingxin; Qian Wang,; Oremland, Ronald S.; Kulp, Thomas R.; Rensing, Christopher; Wang, Gejiao

    2016-01-01

    Antimony (Sb) is a toxic metalloid that occurs widely at trace concentrations in soil, aquatic systems, and the atmosphere. Nowadays, with the development of its new industrial applications and the corresponding expansion of antimony mining activities, the phenomenon of antimony pollution has become an increasingly serious concern. In recent years, research interest in Sb has been growing and reflects a fundamental scientific concern regarding Sb in the environment. In this review, we summarize the recent research on bacterial antimony transformations, especially those regarding antimony uptake, efflux, antimonite oxidation, and antimonate reduction. We conclude that our current understanding of antimony biochemistry and biogeochemistry is roughly equivalent to where that of arsenic was some 20 years ago. This portends the possibility of future discoveries with regard to the ability of microorganisms to conserve energy for their growth from antimony redox reactions and the isolation of new species of “antimonotrophs.”

  8. An investigation of inorganic antimony species and antimony associated with soil humic acid molar mass fractions in contaminated soils

    International Nuclear Information System (INIS)

    Steely, Sarah; Amarasiriwardena, Dulasiri; Xing Baoshan

    2007-01-01

    The presence of antimony compounds is often suspected in the soil of apple orchards contaminated with lead arsenate pesticide and in the soil of shooting ranges. Nitric acid (1 M) extractable Sb from the shooting range (8300 μg kg -1 ) and the apple orchard (69 μg kg -1 ) had considerably higher surface Sb levels than the control site ( -1 ), and Sb was confined to the top ∼30 cm soil layer. Sb(V) was the principal species in the shooting range and the apple orchard surface soils. Size exclusion chromatography-inductively coupled plasma-mass spectrometry (SEC-ICP-MS) analysis of humic acids isolated from the two contaminated soils demonstrated that Sb has complexed to humic acid molar mass fractions. The results also indicate that humic acids have the ability to arrest the mobility of Sb through soils and would be beneficial in converting Sb(III) to a less toxic species, Sb(V), in contaminated areas. - The soil surface and depth distribution Sb(V) and Sb(III) species in a contaminated apple orchard and a shooting range, and the effect soil humic acids on inorganic antimony species is reported

  9. Identification of Potential Biomarkers for Antimony Susceptibility ...

    Indian Academy of Sciences (India)

    Probing natural antimony resistance using customised DNA microarrays with oligos of all ABC transporters · Slide 38 · Comparative proteomics to reveal changes in drug resistant parasites · isobaric tags for relative and absolute quantification (iTRAQ®) allows global analyses of protein expression and quantitative ...

  10. Identification of Potential Biomarkers for Antimony Susceptibility ...

    Indian Academy of Sciences (India)

    Identification of Potential Biomarkers for Antimony Susceptibility/Resistance in L. donovani Rentala Madhubala School of Life Sciences Jawaharlal Nehru ... tags for relative and absolute quantification (iTRAQ®) allows global analyses of protein expression and quantitative comparison among samples by mass spectrometry.

  11. Synthesis and vibrational spectrum of antimony phosphate, SbPO4.

    Science.gov (United States)

    Brockner, Wolfgang; Hoyer, Lars P

    2002-07-01

    SbPO4 was synthesized via a new route by reacting antimony metal with meta-phosphoric acid, (HPO3)n at high temperatures. The Raman and IR spectra of the title compound were recorded and the vibrational modes assigned on the basis of a factor group analysis. The internal vibrations are derived from tetrahedral PO4 units (approaching Sb[PO4]) by the correlation method, although the structure is polymeric and not ionic.

  12. Biodistribution of meglumine antimoniate in healthy and Leishmania (Leishmania infantum chagasi-infected BALB/c mice

    Directory of Open Access Journals (Sweden)

    Samanta Etel Treiger Borborema

    2013-08-01

    Full Text Available Pentavalent antimonials such as meglumine antimoniate (MA are the primary treatments for leishmaniasis, a complex disease caused by protozoan parasites of the genus Leishmania . Despite over 70 years of clinical use, their mechanisms of action, toxicity and pharmacokinetics have not been fully elucidated. Radiotracer studies performed on animals have the potential to play a major role in pharmaceutical development. The aims of this study were to prepare an antimony radiotracer by neutron irradiation of MA and to determine the biodistribution of MA in healthy and Leishmania (Leishmania infantum chagasi-infected mice. MA (Glucantime(r was neutron irradiated inside the IEA-R1 nuclear reactor, producing two radioisotopes, 122Sb and 124Sb, with high radionuclidic purity and good specific activity. This irradiated compound presented anti-leishmanial activity similar to that of non-irradiated MA in both in vitro and in vivo evaluations. In the biodistribution studies, healthy mice showed higher uptake of antimony in the liver than infected mice and elimination occurred primarily through biliary excretion, with a small proportion of the drug excreted by the kidneys. The serum kinetic curve was bi-exponential, with two compartments: the central compartment and another compartment associated with drug excretion. Radiotracers, which can be easily produced by neutron irradiation, were demonstrated to be an interesting tool for answering several questions regarding antimonial pharmacokinetics and chemotherapy.

  13. Speciation analysis of antimony in marine biota by HPLC-(UV)-HG-AFS: Extraction procedures and stability of antimony species.

    Science.gov (United States)

    De Gregori, Ida; Quiroz, Waldo; Pinochet, Hugo; Pannier, Florence; Potin-Gautier, Martine

    2007-09-30

    Speciation analysis of antimony in marine biota is not well documented, and no specific extraction procedure of antimony species from algae and mollusk samples can be found in the literature. This work presents a suitable methodology for the speciation of antimony in marine biota (algae and mollusk samples). The extraction efficiency of total antimony and the stability of Sb(III), Sb(V) and trimethylantimony(V) in different extraction media (water at 25 and 90 degrees C, methanol, EDTA and citric acid) were evaluated by analyzing the algae Macrosystis integrifolia (0.55+/-0.04mugSbg(-1)) and the mollusk Mytilus edulis (0.23+/-0.01mugSbg(-1)). The speciation analysis was performed by anion exchange liquid chromatography (post-column photo-oxidation) and hydride generation atomic fluorescence spectrometry as detection system (HPLC-(UV)-HG-AFS). Results demonstrated that, based on the extraction yield and the stability, EDTA proved to be the best extracting solution for the speciation analysis of antimony in these matrices. The selected procedure was applied to antimony speciation in different algae samples collected from the Chilean coast. Only the inorganic Sb(V) and Sb(III) species were detected in the extracts. In all analyzed algae the sum of total antimony extracted (determined in the extracts after digestion) and the antimony present in the residue was in good agreement with the total antimony concentration determined by HG-AFS. However, in some extracts the sum of antimony species detected was lower than the total extracted, revealing the presence of unknown antimony species, possibly retained on the column or not detected by HPLC-(UV)-HG-AFS. Further work must be carried out to elucidate the identity of these unknown species of antimony.

  14. The presence of antimony in various dental filling materials

    International Nuclear Information System (INIS)

    Molokhia, Anat; Combe, E.C.; Lilley, J.D.

    1985-01-01

    Antimony was determined in a number of non-metallic dental materials currently used for tooth restoration. The method applied was instrumental neutron activation analysis. The concentration of antimony in some of the brands tested was found to be as high as 900 fold that in the normal hard dental tissues. (author)

  15. The exposure to and health effects of antimony

    DEFF Research Database (Denmark)

    Cooper, Ross G.; Harrison, Adrian Paul

    2009-01-01

    of the eyes, skin, and lungs. Long-term inhalation of antimony can potentiate pneumoconiosis, altered electrocardiograms, stomach pain, diarrhea, vomiting, and stomach ulcers, results which were confirmed in laboratory animals. Although there were investigations of the effect of antimony in sudden infant...

  16. Pharmacokinetic of antimony in mice with cutaneous Leishmaniasis

    Energy Technology Data Exchange (ETDEWEB)

    Borborema, Samanta E.T.; Nascimento, Nanci do [Instituto de Pesquisas Energeticas e Nucleares IPEN/CNEN-SP, Sao Paulo, SP (Brazil). Lab. de Biologia Molecular]. E-mails: samanta@usp.br; nnascime@ipen.br; Andrade Junior, Heitor F. de [Instituto de Pesquisas Energeticas e Nucleares IPEN/CNEN-SP, Sao Paulo, SP (Brazil). Lab. de Biologia Molecular; Instituto de Medicina Tropical de Sao Paulo, Sao Paulo, SP (Brazil); E-mail: hfandrad@usp.br; Osso Junior, Joao A. [Instituto de Pesquisas Energeticas e Nucleares IPEN/CNEN-SP, Sao Paulo, SP (Brazil). Centro de Radiofarmacia]. E-mail: jaosso@ipen.br

    2007-07-01

    Cutaneous Leishmaniasis (CL) remains a major world health problem, with about 1.5 million new cases each year. Caused by protozoa Leishmania, in South America, this infection can vary from a chronic skin ulcer, to an erosive mucosal disease and severe facial disfigurement. Pentavalent antimony (Sb{sup +5}) as sodium stibogluconate (Pentostam) or meglumine antimoniate (Glucantime) are main drugs for treating most forms of human leishmaniasis. For six decades, despite the recent developments, the effective therapy to cutaneous leishmaniasis has been based on long parenteral courses of such drugs, even though these are fairly costly, toxic and inconvenient to use, without adequate knowledge on their pharmacokinetics or mechanism of action. Pharmacokinetics studies could be based on bioactive traceable drugs, usually with radioactive isotopes, but antimony radioisotopes are unavailable commercially. Neutron irradiation is a powerful tool in the analysis of mineral content of samples, for antimony, there are at least two main isotopes that could be formed after neutron irradiation in nuclear reactor. The aim of the present study was to construct antimony salts with those radioisotopes to obtain tracers to compare the pharmacokinetic and the tissue distribution of neutron irradiated meglumine antimoniate in healthy and cutaneous leishmaniasis experimentally infected mice. Meglumine antimoniate, (Glucantime, Aventis, S.P, Brazil), was neutron irradiated inside the IEA-R1 nuclear reactor (IPEN/CNEN-SP), producing two radioisotopes {sup 122}Sb and {sup 124}Sb. Its biodistribution was verified in BALB/c mice experimentally infected with Leishmania (Leishmania) Amazonensis, which received a single intraperitoneal dose of the drug. At different times after injection, the tissues and blood were excised and activity measured in a NaI (Tl) scintillation counter. Compared with the healthy mice, experimentally infected mice had significantly lower maximum concentration of antimony

  17. Antimony in the Contaminated Site of El Triunfo, Baja California Sur, Mexico

    Directory of Open Access Journals (Sweden)

    Marmolejo-Rodríguez A. J.

    2013-04-01

    Full Text Available Antimony has properties similar to arsenic with some of its compounds toxic to humans. Therefore it is necessary to control the wastes accumulated by anthropogenic activities, such as mining, where it is in tailings to be released to the environment. According to the Environment Protection Agency, the maximum value in sediments is 11.2 mg Sb kg–1 and the Earth’s crust average is 0.2 mg Sb kg–1. In this semiarid area, the drainage basin El Carrizal is impacted with wastes of an abandoned gold mine at the Mining District El Triunfo (MD – ET which have tailings with 17,600 mg kg–1 of antimony. In the main dry river (arroyo, the Sb content is between 0.6 and 122 mg kg–1. This element is transported from the source throughout the fluvial basin to discharge into the Pacific Ocean. In the arroyo mouth we collected one sedimentary core and the sediment from dunes (28.6 – 45.7 and 6.43 – 7.74 mg Sb kg–1. This research concluded the antimony is enriched in this semiarid system, with Normalized Enrichment Factors severely enriched mainly in arroyo sediments close to the MD-ET

  18. Sequestration of Antimony on Calcite Observed by Time-Resolved Nanoscale Imaging.

    Science.gov (United States)

    Renard, François; Putnis, Christine V; Montes-Hernandez, German; King, Helen E; Breedveld, Gijs D; Okkenhaug, Gudny

    2018-01-02

    Antimony, which has damaging effects on the human body and the ecosystem, can be released into soils, ground-, and surface waters either from ore minerals that weather in near surface environments, or due to anthropogenic releases from waste rich in antimony, a component used in batteries, electronics, ammunitions, plastics, and many other industrial applications. Here, we show that dissolved Sb can interact with calcite, a widespread carbonate mineral, through a coupled dissolution-precipitation mechanism. The process is imaged in situ, at room temperature, at the nanometer scale by using an atomic force microscope equipped with a flow-through cell. Time-resolved imaging allowed following the coupled process of calcite dissolution, nucleation of precipitates at the calcite surface and growth of these precipitates. Sb(V) forms a precipitate, whereas Sb(III) needs to be oxidized to Sb(V) before being incorporated in the new phase. Scanning-electron microscopy and Raman spectroscopy allowed identification of the precipitates as two different calcium-antimony phases (Ca 2 Sb 2 O 7 ). This coupled dissolution-precipitation process that occurs in a boundary layer at the calcite surface can sequester Sb as a solid phase on calcite, which has environmental implications as it may reduce the mobility of this hazardous compound in soils and groundwaters.

  19. pH-regulated antimony oxychloride nanoparticle formation on titanium oxide nanostructures: a photocatalytically active heterojunction

    KAUST Repository

    Buchholcz, Balázs

    2017-02-06

    Improving the catalytic activity of heterogeneous photocatalysts has become a hot topic recently. To this end, considerable progress has been made in the efficient separation of photogenerated charge carriers by e.g. the realization of heterojunction photocatalysts. V-VI-VII compound semiconductors, namely, bismuth oxyhalides, are popular photocatalysts. However, results on antimony oxyhalides [SbOX (X = Br, Cl, I)], the very promising alternatives to the well-known BiOX photomodifiers, are scarce. Here, we report the successful decoration of titanium oxide nanostructures with 8-11 nm diameter SbOX nanoparticles for the first time ever. The product size and stoichiometry could be controlled by the pH of the reactant mixture, while subsequent calcination could transform the structure of the titanate nanotube (TiONT) support and the prepared antimony oxychloride particles. In contrast to the ease of composite formation in the SbOX/TiONT case, anatase TiO could not facilitate the formation of antimony oxychloride nanoparticles on its surface. The titanate nanotube-based composites showed activity in a generally accepted quasi-standard photocatalytic test reaction (methyl orange dye decolorization). We found that the SbOCl/TiONT synthesized at pH = 1 is the most active sample in a broad temperature range.

  20. Mixed Antimony(V Complexes with Different Sugars to Modulate the Oral Bioavailability of Pentavalent Antimonial Drugs

    Directory of Open Access Journals (Sweden)

    Weverson A. Ferreira

    2014-04-01

    Full Text Available Previous studies have shown that the association of the drug meglumine antimoniate (MA with β-cyclodextrin can improve its bioavailability by the oral route. In this work, ribose and maltose were investigated for their ability to form mixed or association complexes with MA, release MA and modulate the serum levels of Sb after oral administration in mice. Analysis of the MA/ribose composition by high performance liquid chromatography coupled to mass spectrometry (LCMS-IT-TOF revealed the presence of mixed meglumine-Sb-ribose and Sb-ribose complexes. Analysis of the MA/maltose composition suggested the formation of MA-maltose association compounds. Circular dichroism characterization of these compositions following dilution in water at 37 °C suggested a partial and slow dissociation of the association compounds. When the MA/ribose composition was administered orally and compared to MA, the serum concentration of Sb was significantly lower after 1 h and greater after 3 h. On the other hand, the MA/maltose composition showed similar serum Sb concentration after 1 h and higher level of Sb after 3 h, when compared to MA. In conclusion, the present study has demonstrated the formation of mixed or association complexes of MA with sugars, such as maltose and ribose, which promoted sustained serum level of Sb after oral administration.

  1. Structural and electrical characterization of zinc oxide doped with antimony

    Directory of Open Access Journals (Sweden)

    G. Juárez Díaz

    2014-08-01

    Full Text Available In this work we report the results of structural and electrical characterization realized on zinc oxide single crystal samples with (001 orientation, which were doped with antimony. Doping was carried out by antimony thermal diffusion at 1000 °C for periods of 1 and 2 hours under nitrogen environment from a solid source formed by antimony oxide. Electrical characterization by I-V curves and Hall effect shown an increase in acceptor concentration which demonstrates that doping is effective and create holes in zinc oxide samples.

  2. Quantitative HPLC-ICP-MS analysis of antimony redox speciation in complex sample matrices: new insights into the Sb-chemistry causing poor chromatographic recoveries

    DEFF Research Database (Denmark)

    Hansen, Claus; Schmidt, Bjørn; Larsen, Erik Huusfeldt

    2011-01-01

    of low chromatographic recoveries. A combination of HPLC-ICP-MS, AFFF-ICP-MS and spinfiltration was applied for analysis of model compounds and biological samples. Quantitative chromatographic Sb redox speciation analysis was possible by acidic hydrolysis of the antimony polymers prior to analysis...

  3. Cyanide and antimony thermodynamic database for the aqueous species and solids for the EPA-MINTEQ geochemical code

    International Nuclear Information System (INIS)

    Sehmel, G.A.

    1989-05-01

    Thermodynamic data for aqueous species and solids that contain cyanide and antimony were tabulated from several commonly accepted, published sources of thermodynamic data and recent journal article. The review does not include gases or organic complexes of either antimony or cyanide, nor does the review include the sulfur compounds of cyanide. The basic thermodynamic data, ΔG/sub f,298//sup o/, ΔH/sub f,298//sup o/, and S/sub f//sup o/ values, were chosen to represent each solid phase and aqueous species for which data were available in the appropriate standard state. From these data the equilibrium constants (log K/sub r,298//sup o/) and enthalpies of reaction (ΔH/sub r,298//sup o/) at 298 K (25/degree/C) were calculated for reactions involving the formation of these aqueous species and solids from the basic components. 34 refs., 14 tabs

  4. Complex processing of antimony-mercury gold concentrates of Dzhizhikrut Deposit

    International Nuclear Information System (INIS)

    Abdusalyamova, M.N.; Gadoev, S.A.; Dreisinger, D.; Solozhenkin, P.M.

    2013-01-01

    Present article is devoted to complex processing of antimony-mercury gold concentrates of Dzhizhikrut Deposit. The purpose of research was obtaining the metallic mercury and antimony with further gold and thallium extraction.

  5. Martensite transformation in antimony implanted stainless steel

    International Nuclear Information System (INIS)

    Johnson, E.; Littmark, U.; Johansen, A.; Christodoulides, C.

    1981-01-01

    The authors have used Rutherford backscattering analysis (RBS) and transmission electron microscopy (TEM) and diffraction to investigate austenitic stainless steel crystals implanted at room temperature with 80 keV Sb + ions to a fluence of 5 x 10 20 ions/m 2 , thus providing implantation with a heavy group V element. RBS channeling spectra from implanted crystals show a damage peak which approaches the height of the random level and therefore indicates a very high degree of disorder in the implanted layers. The distribution of the disorder extends to a depth 3-5 times the depth of the primary radiation damage. The Sb peaks under channeling as well as random conditions are indistinguishable, confirming that substitutionality during implantation is negligible. To establish the nature of the disorder which cannot be assessed from the RBS analysis alone, and in particular to assess whether an amorphous alloy is formed in the implanted layer as indicated from the RBS spectra, samples implanted under similar conditions were investigated in the TEM. Significant extra spots in the patterns can be ascribed to the presence of a radiation induced b.c.c. phase of martensitic origin. The result that a significant amount of martensite can be induced by antimony implantation seems to indicate that the main driving force for the transition is due to damage induced stress concentrations. (Auth.)

  6. Field-portable-XRF reveals the ubiquity of antimony in plastic consumer products.

    Science.gov (United States)

    Turner, Andrew; Filella, Montserrat

    2017-04-15

    Very little systematic information exists on the occurrence and concentrations of antimony (Sb) in consumer products. In this study, a Niton XL3t field-portable-X-ray fluorescence (FP-XRF) spectrometer was deployed in situ and in the laboratory to provide quantitative information on Sb dissipated in plastic items and fixtures (including rubber, textile and foamed materials) from the domestic, school, vehicular and office settings. The metalloid was detected in 18% of over 800 measurements performed, with concentrations ranging from about 60 to 60,000μgg -1 . The highest concentrations were encountered in white, electronic casings and in association with similar concentrations of Br, consistent with the use of antimony oxides (e.g. Sb 2 O 3 ) as synergistic flame retardants. Concentrations above 1000μgg -1 , and with or without Br, were also encountered in paints, piping and hosing, adhesives, whiteboards, Christmas decorations, Lego blocks, document carriers, garden furniture, upholstered products and interior panels of private motor vehicles. Lower concentrations of Sb were encountered in a wide variety of items but its presence (without Br) in food tray packaging, single-use drinks bottles, straws and small toys were of greatest concern from a human health perspective. While the latter observations are consistent with the use of antimony compounds as catalysts in the production of polyethylene terephthalate, co-association of Sb and Br in many products not requiring flame retardancy suggests that electronic casings are widely recycled. Further research is required into the mobility of Sb when dissipated in new, recycled and aged polymeric materials. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Semiconducting III-V compounds

    CERN Document Server

    Hilsum, C; Henisch, Heinz R

    1961-01-01

    Semiconducting III-V Compounds deals with the properties of III-V compounds as a family of semiconducting crystals and relates these compounds to the monatomic semiconductors silicon and germanium. Emphasis is placed on physical processes that are peculiar to III-V compounds, particularly those that combine boron, aluminum, gallium, and indium with phosphorus, arsenic, and antimony (for example, indium antimonide, indium arsenide, gallium antimonide, and gallium arsenide).Comprised of eight chapters, this book begins with an assessment of the crystal structure and binding of III-V compounds, f

  8. [Pollution characteristics of antimony, arsenic and mercury in human hair at Xikuangshan antimony mining area and Guiyang City, China].

    Science.gov (United States)

    Liu, Bi-Jun; Wu, Feng-Chang; Deng, Qiu-Jing; Mo, Chang-Li; Zhu, Jing; Zeng, Li; Fu, Zhi-You; Li, Wen

    2009-03-15

    The concentration levels of antimony, arsenic and mercury in human hair collected from Xikuangshan antimony mining area and Guiyang City were determined by hydride generation-atomic fluorescence spectrometry after having been digested by nitric acid and perchloric acid. The contents of Sb, As and Hg are 15.9, 4.21, 1.79 microg/g in the samples from Xikuangshan antimony mining area and 0.532, 0.280, 0.338 microg/g in the samples from Guiyang City respectively. The contents of Sb, As and Hg in human hair of Xikuangshan antimony area are much higher than those of Guiyang City. The independent-samples t-test shows that there are no marked differences in the contents of Sb and As between male and female hair samples from both Xikuangshan antimony mining area and Guiyang City (p > 0.05), while Hg contents in male hair are apparently higher than those in female hair from Guiyang City (p mining area may significantly affect human health than in the un-mining areas.

  9. Heat-treated Saccharomyces cerevisiae for antimony speciation and antimony(III) preconcentration in water samples

    Energy Technology Data Exchange (ETDEWEB)

    Marcellino, Sebastien [Universite de Lyon, Lyon1, Laboratoire des Sciences Analytiques, CNRS UMR 5180, bat CPE, 43, boulevard du 11 novembre 1918, 69622 Villeurbanne cedex (France); Attar, Hossein [Universite Louis Pasteur de Strasbourg, Laboratoire de Chimie Analytique et Sciences Separatives, CNRS UMR 7178, ECPM, 25 rue Becquerel 67087 Strasbourg (France); Lievremont, Didier; Lett, Marie-Claire [Universite Louis Pasteur de Strasbourg, Laboratoire de Genetique Moleculaire, Genetique et Microbiologie, CNRS UMR 7156, 28 rue Goethe, 67000 Strasbourg (France); Barbier, Frederique [CNRS USR 59, Service Central d' Analyse, 59 Chemin du Canal BP22 69390 Vernaison (France); Lagarde, Florence [Universite de Lyon, Lyon1, Laboratoire des Sciences Analytiques, CNRS UMR 5180, bat CPE, 43, boulevard du 11 novembre 1918, 69622 Villeurbanne cedex (France); Universite Louis Pasteur de Strasbourg, Laboratoire de Chimie Analytique et Sciences Separatives, CNRS UMR 7178, ECPM, 25 rue Becquerel 67087 Strasbourg (France)], E-mail: florence.lagarde@univ-lyon1.fr

    2008-11-23

    An analytical method was developed for antimony speciation and antimony(III) preconcentration in water samples. The method is based on the selective retention of Sb(III) by modified Saccharomyces cerevisiae in the presence of Sb(V). Heat, caustic and solvent pretreatments of the biomass were investigated to improve the kinetics and thermodynamics of Sb(III) uptake process at room temperature. Heating for 30 min at 80 deg. C was defined as the optimal treatment. Antimony accumulation by the cells was independent of pH (5-10) and ionic strength (0.01-0.1 mol L{sup -1}). 140 mg of yeast and 2 h of contact were necessary to ensure quantitative sequestration of Sb(III) up to 750 {mu}g L{sup -1}. In these conditions, Sb(V) was not retained. Sb(V) was quantified in sorption supernatant by inductively coupled plasma mass spectrometry (ICP-MS) or inductively coupled plasma optical emission spectrometry (ICP-OES). Sb(III) was determined after elution with 40 mmol L{sup -1} thioglycolic acid at pH 10. A preconcentration factor close to nine was achieved for Sb(III) when 100 mL of sample was processed. After preconcentration, the detection limits for Sb(III) and Sb(V) were 2 and 5 ng L{sup -1}, respectively, using ICP-MS, 7 and 0.9 {mu}g L{sup -1} using ICP-OES. The proposed method was successfully applied to the determination of Sb(III) and Sb(V) in spiked river and mineral water samples. The relative standard deviations (n = 3) were in the 2-5% range at the tenth {mu}g L{sup -1} level and less than 10% at the lowest Sb(III) and Sb(V) tested concentration (0.1 {mu}g L{sup -1}). Corrected recoveries were in all cases close to 100%.

  10. Nanoscaled hydrated antimony (V oxide as a new approach to first-line antileishmanial drugs

    Directory of Open Access Journals (Sweden)

    Franco AMR

    2016-12-01

    Full Text Available Antonia MR Franco,1 Iryna Grafova,2 Fabiane V Soares,1,3 Gennaro Gentile,4 Claudia DC Wyrepkowski,1,3 Marcos A Bolson,5 Ézio Sargentini Jr,5 Cosimo Carfagna,4 Markku Leskelä,2 Andriy Grafov2 1Laboratory of Leishmaniasis and Chagas Disease, National Institute of Amazonian Research (INPA, Manaus, Amazonas, Brazil; 2Department of Chemistry, University of Helsinki, Helsinki, Finland; 3Multi-Institutional Post-Graduate Program in Biotechnology, Federal University of Amazonas, Manaus, Amazonas, Brazil; 4Institute for Polymers, Composites, and Biomaterials, National Research Council, Pozzuoli, Naples Province, Italy; 5Laboratory of Environmental Chemistry, National Institute of Amazonian Research (INPA, Manaus, Amazonas, Brazil Background: Coordination compounds of pentavalent antimony have been, and remain, the first-line drugs in leishmaniasis treatment for >70 years. Molecular forms of Sb (V complexes are commercialized as sodium stibogluconate (Pentostam® and meglumine antimoniate (MA (Glucantime®. Ever-increasing drug resistance in the parasites limits the use of antimonials, due to the low drug concentrations being administered against high parasitic counts. Sb5+ toxicity provokes severe side effects during treatment. To enhance therapeutic potency and to increase Sb (V concentration within the target cells, we decided to try a new active substance form, a hydrosol of Sb2O5⋅nH2O nanoparticles (NPs, instead of molecular drugs. Methodology/principal findings: Sb2O5⋅nH2O NPs were synthesized by controlled SbCl5 hydrolysis in a great excess of water. Sb2O5⋅nH2O phase formation was confirmed by X-ray diffraction. The surface of Sb (V NPs was treated with ligands with a high affinity for target cell membrane receptors. The mean particle size determined by dynamic light scattering and transmission electron microscopy was ~35–45 nm. In vitro tests demonstrated a 2.5–3 times higher antiparasitic activity of Sb (V nanohybrid hydrosols

  11. Antimony speciation analysis in sediment reference materials using high-performance liquid chromatography coupled to hydride generation atomic fluorescence spectrometry

    International Nuclear Information System (INIS)

    Potin-Gautier, M.; Pannier, F.; Quiroz, W.; Pinochet, H.; Gregori, I. de

    2005-01-01

    This work presents the development of suitable methodologies for determination of the speciation of antimony in sediment reference samples. Liquid chromatography with a post-column photo-oxidation step and hydride generation atomic fluorescence spectrometry as detection system is applied to the separation and determination of Sb(III), Sb(V) and trimethylantimony species. Post-column decomposition and hydride generation steps were studied for sensitive detection with the AFS detector. This method was applied to investigate the conditions under which speciation analysis of antimony in sediment samples can be carried out. Stability studies of Sb species during the extraction processes of solid matrices, using different reagents solutions, were performed. Results demonstrate that for the extraction yield and the stability of Sb species in different marine sediment extracts, citric acid in ascorbic acid medium was the best extracting solution for antimony speciation analysis in this matrix (between 55% and 65% of total Sb was recovered from CRMs, Sb(III) being the predominant species). The developed method allows the separation of the three compounds within 6 min with detection limits of 30 ng g -1 for Sb(III) and TMSbCl2 and 40 ng g -1 for Sb(V) in sediment samples

  12. Antimony speciation analysis in sediment reference materials using high-performance liquid chromatography coupled to hydride generation atomic fluorescence spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Potin-Gautier, M. [Laboratoire de Chimie Analytique, BioInorganique et Environnement LCABIE (UMR CNRS 3054), Universite de Pau et des pays de l' Adour, 64000 Pau (France); Pannier, F. [Laboratoire de Chimie Analytique, BioInorganique et Environnement LCABIE (UMR CNRS 3054), Universite de Pau et des pays de l' Adour, 64000 Pau (France)]. E-mail: Florence.pannier@univ-pau.fr; Quiroz, W. [Laboratoire de Chimie Analytique, BioInorganique et Environnement LCABIE (UMR CNRS 3054), Universite de Pau et des pays de l' Adour, 64000 Pau (France); Laboratorio de Quimica Analitica y Ambiental, Instituto de Quimica, Pontificia Universidad catolica de Valparaiso (Chile); Pinochet, H. [Laboratorio de Quimica Analitica y Ambiental, Instituto de Quimica, Pontificia Universidad catolica de Valparaiso (Chile); Gregori, I. de [Laboratorio de Quimica Analitica y Ambiental, Instituto de Quimica, Pontificia Universidad catolica de Valparaiso (Chile)

    2005-11-30

    This work presents the development of suitable methodologies for determination of the speciation of antimony in sediment reference samples. Liquid chromatography with a post-column photo-oxidation step and hydride generation atomic fluorescence spectrometry as detection system is applied to the separation and determination of Sb(III), Sb(V) and trimethylantimony species. Post-column decomposition and hydride generation steps were studied for sensitive detection with the AFS detector. This method was applied to investigate the conditions under which speciation analysis of antimony in sediment samples can be carried out. Stability studies of Sb species during the extraction processes of solid matrices, using different reagents solutions, were performed. Results demonstrate that for the extraction yield and the stability of Sb species in different marine sediment extracts, citric acid in ascorbic acid medium was the best extracting solution for antimony speciation analysis in this matrix (between 55% and 65% of total Sb was recovered from CRMs, Sb(III) being the predominant species). The developed method allows the separation of the three compounds within 6 min with detection limits of 30 ng g{sup -1} for Sb(III) and TMSbCl2 and 40 ng g{sup -1} for Sb(V) in sediment samples.

  13. Antimony recovery from end-of-life products and industrial process residues: A critical review

    OpenAIRE

    Dupont, David; Arnout, Sander; Jones, Peter Tom; Binnemans, Koen

    2016-01-01

    Antimony has become an increasingly critical element in recent years, due to a surge in industrial demand and the Chinese domination of primary production. Antimony is produced from stibnite ore (Sb2O3) which is processed into antimony metal and antimony oxide (Sb2O3). The industrial importance of antimony is mainly derived from its use as flame retardant in plastics, coatings, and electronics, but also as decolourizing agent in glass, alloys in lead-acid batteries, and catalysts for the p...

  14. Application of Hyphenated Techniques in Speciation Analysis of Arsenic, Antimony, and Thallium

    Directory of Open Access Journals (Sweden)

    Rajmund Michalski

    2012-01-01

    Full Text Available Due to the fact that metals and metalloids have a strong impact on the environment, the methods of their determination and speciation have received special attention in recent years. Arsenic, antimony, and thallium are important examples of such toxic elements. Their speciation is especially important in the environmental and biomedical fields because of their toxicity, bioavailability, and reactivity. Recently, speciation analytics has been playing a unique role in the studies of biogeochemical cycles of chemical compounds, determination of toxicity and ecotoxicity of selected elements, quality control of food products, control of medicines and pharmaceutical products, technological process control, research on the impact of technological installation on the environment, examination of occupational exposure, and clinical analysis. Conventional methods are usually labor intensive, time consuming, and susceptible to interferences. The hyphenated techniques, in which separation method is coupled with multidimensional detectors, have become useful alternatives. The main advantages of those techniques consist in extremely low detection and quantification limits, insignificant interference, influence as well as high precision and repeatability of the determinations. In view of their importance, the present work overviews and discusses different hyphenated techniques used for arsenic, antimony, and thallium species analysis, in different clinical, environmental and food matrices.

  15. Application of Hyphenated Techniques in Speciation Analysis of Arsenic, Antimony, and Thallium

    Science.gov (United States)

    Michalski, Rajmund; Szopa, Sebastian; Jabłońska, Magdalena; Łyko, Aleksandra

    2012-01-01

    Due to the fact that metals and metalloids have a strong impact on the environment, the methods of their determination and speciation have received special attention in recent years. Arsenic, antimony, and thallium are important examples of such toxic elements. Their speciation is especially important in the environmental and biomedical fields because of their toxicity, bioavailability, and reactivity. Recently, speciation analytics has been playing a unique role in the studies of biogeochemical cycles of chemical compounds, determination of toxicity and ecotoxicity of selected elements, quality control of food products, control of medicines and pharmaceutical products, technological process control, research on the impact of technological installation on the environment, examination of occupational exposure, and clinical analysis. Conventional methods are usually labor intensive, time consuming, and susceptible to interferences. The hyphenated techniques, in which separation method is coupled with multidimensional detectors, have become useful alternatives. The main advantages of those techniques consist in extremely low detection and quantification limits, insignificant interference, influence as well as high precision and repeatability of the determinations. In view of their importance, the present work overviews and discusses different hyphenated techniques used for arsenic, antimony, and thallium species analysis, in different clinical, environmental and food matrices. PMID:22654649

  16. Selective oxidation of propene on bismuth molybdate and mixed oxides of tin and antimony and of uranium and antimony

    International Nuclear Information System (INIS)

    Pendleton, P.; Taylor, D.

    1976-01-01

    Propene + 18 0 2 reactions have been studied in a static reaction system on bismuth molybdate and mixed oxides of tin and antimony and of uranium and antimony. The [ 16 0] acrolein content of the total acrolein formed and the proportion of 16 0 in the oxygen of the carbon dioxide by-product have been determined. The results indicate that for each catalyst the lattice is the only direct source of the oxygen in the aldehyde, and that lattice and/or gas phase oxygen is used in carbon dioxide formation. Oxygen anion mobility appears to be greater in the molybdate catalyst than in the other two. (author)

  17. Neutron activation analysis of arsenic and antimony in human hair

    International Nuclear Information System (INIS)

    Kanda, Yukio; Isono, Hideo; Kozuka, Hiroshi.

    1975-01-01

    A radiochemical neutron activation method for the determination of trace amounts of arsenic and antimony in human hair samples is studied. The sample of hair (100 mg) irradiated for 5 hours with a neutron flux of 2.1x10 12 n/cm 2 s was decomposed with a sulfuric-nitric acid mixture after addition of each 5 mg of arsenic and antimony as carrier. Arsine and stibine were evolved from the solution of decomposed hair by reduction with 3 g of granular zinc and were absorbed in 0.1N iodine solution for half an hour. Metal arsenic was separated from iodine solution by precipitation with sodium hypophosphite, followed by precipitation of antimony as sulfide with thioacetamide. These precipitates were dissolved and their gamma-ray spectra were measured with a well type 3''x3'' NaI(TI) detector equipped with a 200 channel pulse-height analyzer. After the measurement of gamma-ray spectra, the chemical yields were determined by colorimetric methods. The relative standard deviations were 7% and 4% for 0.01 μg As and 0.024 μg Sb, respectively. The sensitivity of this method was estimated to be 1x10 -3 μg for arsenic and 2x10 -3 μg for antimony. (auth.)

  18. Electrical Properties of Antimony (Sb) Metal Contacts to Silicon (Si ...

    African Journals Online (AJOL)

    The study investigates the behaviour of the contacts formed by Antimony (Sb) metal to Silicon (Si) thin films for electric field values 10 – 100V/m. Measurements of I-v characteristics were obtained at temperatures 303, 313, 323, 333, 343 and 353K respectively. The results show linear I – V relationship over a specified range ...

  19. electrocardiographic findings in ethiopians on penta valent antimony ...

    African Journals Online (AJOL)

    East Africa Medical Journal Vol. 78 No. 11 November 2001. ELECTROCARDIOGRAPHIC FINDINGS IN ETHIOPIANS ON PENTA VALENT ANTIMONY THERAPY FOR VISCERAL LEISHMANIASIS. N. Berhe, MD, DTMH, Institute of Pathobiology, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia, Y. Abraham, ...

  20. Vapor pressures of dimethylcadmium, trimethylbismuth, and tris(dimethylamino)antimony

    Czech Academy of Sciences Publication Activity Database

    Morávek, Pavel; Fulem, Michal; Pangrác, Jiří; Hulicius, Eduard; Růžička, K.

    2013-01-01

    Roč. 360, Dec (2013), s. 106-110 ISSN 0378-3812 R&D Projects: GA ČR GA13-15286S; GA MŠk(CZ) LM2011026 Institutional support: RVO:68378271 Keywords : vapor pressure * dimethylcadmium * trimethylbismuth * tris(dimethylamino)antimony * sublimation and vaporization enthalpy Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.241, year: 2013

  1. Application of KWU antimony removal process at Gentilly-2

    International Nuclear Information System (INIS)

    Dundar, Y.; Odar, S.; Streit, K.; Allsop, H.; Guzonas, D.

    1996-09-01

    This paper describes the work performed to adapt the KWU PWR antimony removal process to CANDU plant conditions, and the application of the process at the Hydro Quebec unit, Gentilly-2. The results of the application will be presented and the 'lessons learned' will be discussed in detail. (author)

  2. Antimony content of macrofungi from clean and polluted areas

    Czech Academy of Sciences Publication Activity Database

    Borovička, J.; Řanda, Zdeněk; Jelínek, E.

    2006-01-01

    Roč. 64, č. 11 (2006), s. 1837-1844 ISSN 0045-6535 Institutional research plan: CEZ:AV0Z10480505 Keywords : mushrooms * antimony pollution * bioaccumulation Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 2.442, year: 2006

  3. The decoration of vicinal copper polycrystalline surface by Antimony

    CSIR Research Space (South Africa)

    Ndlovu, GF

    2011-07-01

    Full Text Available An Ultra-high Vacuum Variable Temperature Scanning Tunnelling Microscope was used to study the growth mechanism of Antimony on vicinal Cu polycrystalline samples. The STM data after deposition of 0.3 ML Sb at 300°C showed localization of Sb atoms...

  4. Antimony and arsenic biogeochemistry in the East China Sea

    Science.gov (United States)

    Ren, Jing-Ling; Zhang, Xu-Zhou; Sun, You-Xu; Liu, Su-Mei; Huang, Daji; Zhang, Jing

    2016-02-01

    The biogeochemical cycles of the metalloid elements arsenic and antimony in the East China Sea (ECS), one of the most important marginal seas for western Pacific, were examined in May 2011. Dissolved inorganic arsenic (As(V) and As(III)) and antimony (Sb(V) and Sb(III)) species were determined by selective hydride generation-atomic fluorescence spectrometry (HG-AFS). Results show that total dissolved inorganic arsenic (TDIAs; [TDIAs]=[As(V)]+[As(III)]) were moderately depleted in the surface water and enriched in the deep water. Arsenite (As(III)) showed different vertical profiles with that of TDIAs, with significant surface enrichment in the middle shelf region where the concentrations of phosphate were extremely low. Speciation of dissolved arsenic was subtly controlled by the stoichiometric molar ratio of arsenate (As(V)) to phosphate. The average As(V)/P ratio for the ECS in spring 2011 was 10.8×10-3, which is higher than previous results and indicates the arsenate stress. The concentrations of total dissolved inorganic antimony (TDISb; [TDISb]=[Sb(V)]+[Sb(III)]) were high near the Changjiang Estuary and the coastal area of Hangzhou Bay and decreased moderately off the coast. TDISb displayed moderate conservative behavior in the ECS that confirms by the correlations with salinity and dissolved aluminum. Different with that of As(III), antimonite (Sb(III)) concentrations were extremely lower in the ECS, with relative higher concentration appeared at the bottom layer which indicates the contribution from sediment-water interface. A preliminary box model was established to estimate the water-mass balance and antimony budgets for the ECS. Compared with other areas in the world, the concentrations of dissolved inorganic arsenic and antimony in the ECS remain at natural levels.

  5. A Novel Framework Antimony (III) Phosphate: Synthesis and Structure of NaSb 3O 2(PO 4) 2

    Science.gov (United States)

    Adair, Brian A.; de Delgado, Graciela Díaz; Miguel Delgado, J.; Cheetham, Anthony K.

    2000-04-01

    The antimony (III) phosphate, NaSb3O2(PO4)2, is a framework structure built from SbIII and PV centers; orthorhombic, space group Pca21 (No. 29), a=13.944(3), b=6.6822(13), c=20.886(4) Å, V=1946.1(7) Å3, Z=8. Stereochemically active lone pairs of electrons associated with SbIIIO5 and SbIIIO4 polyhedra point into eight-ring channels, approximately 5×7 Å2, which dominate the architecture of the title compound. Charge-compensating sodium cations occupy the remaining space in the channels.

  6. BioGeochemistry of antimony, Sources, Transfers, Impacts and Assessment

    Science.gov (United States)

    Le Roux, Gael; Pinelli, Eric; Hedde, Mickael; Guiresse, Maritxu; De Vleeschouwer, François; Silvestre, Jérôme; Enrico, Maxime; Gandois, Laure; Monna, Fabrice; Gers, Charles; Probst, Anne

    2013-04-01

    BioGeoSTIB is a project funded by ADEME (French Environmental Protection Agency). Its aim is to provide a better understanding of biogeochemical cycle disturbances of antimony by man. Specifically, it is focused on the atmosphere-soil-organism interfaces. Based on a multi-scale approach, the impact of antimony on organisms and organism communities and the factors of Sb dispersion in the environment aim to better characterized. This report gives the main results of 2 and 1 -2 years of research. Using peat bogs as environmental archives, we show that Sb contamination in soils date back to the beginning of the metallurgy. Atmospheric deposition of Sb largely increased by 100 times during the Industrial Revolution compared to natural levels (~0,001-0,01 mg m-2 an-1) estimated in the deepest peat layers. This disturbance in the antimony geochemical cycle modified its concentrations in soils. One main source of present Sb contamination is automotive traffic due to Sb in braking lines. This emerging contamination was characterized close to a roundabout. This additional source of Sb does not seem to impact soil fauna but Sb concentrations in soil solutions exceed 1 μg L-1. Genotoxicity tests have been performed on the model plant Vicia faba and show that antimony is genotoxic at its lowest concentrations and that there is a synergistic effect lead, a trace metal frequently found in association with antimony in the environment. It is a main issue to determine Sb critical loads in the environment but main identified lacks are thermodynamic data, which are not available yet, to model the behavior of Sb in soil solutions and the fact the antimony is always associated with other anthropogenic trace metals like lead. Critical thresholds of Sb have been determined for the first time based on genotoxicity experiment. Simulations show that these thresholds can be exceeded in the future, whereas present limits for invertebrates (US-EPA) are and will not be reached. However

  7. Cytotoxicity and In Vitro Antileishmanial Activity of Antimony (V), Bismuth (V), and Tin (IV) Complexes of Lapachol.

    Science.gov (United States)

    Rocha, Marcele Neves; Nogueira, Paula Monalisa; Demicheli, Cynthia; de Oliveira, Ludmila Gonçalvez; da Silva, Meiriane Mariano; Frézard, Frédéric; Melo, Maria Norma; Soares, Rodrigo Pedro

    2013-01-01

    Leishmania amazonensis is the etiologic agent of the cutaneous and diffuse leishmaniasis often associated with drug resistance. Lapachol [2-hydroxy-3-(3'-methyl-2-butenyl)-1,4-naphthoquinone] displays a wide range of antimicrobial properties against many pathogens. In this study, using the classic microscopic in vitro model, we have analyzed the effects of a series of lapachol and chlorides complexes with antimony (V), bismuth (V), and tin (IV) against L. amazonensis. All seven compounds exhibited antileishmanial activity, but most of the antimony (V) and bismuth (V) complexes were toxic against human HepG2 cells and murine macrophages. The best IC50 values (0.17 ± 0.03 and 0.10 ± 0.11 μg/mL) were observed for Tin (IV) complexes (3) [(Lp)(Ph3Sn)] and (6) (Ph3SnCl2), respectively. Their selective indexes (SIs) were 70.65 and 120.35 for HepG2 cells, respectively. However, while analyzing murine macrophages, the SI decreased. Those compounds were moderately toxic for HepG2 cells and toxic for murine macrophages, still underlying the need of chemical modification in this class of compounds.

  8. Synthesis and characterization of copper antimony tin sulphide thin films for solar cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Ali, N., E-mail: nisar.ali@utm.my [Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, UTM Skudai, 81310 Johor (Malaysia); Department of Physics, Govt. Post Graduate Jehanzeb College Saidu Sharif, Swat, 19200 (Pakistan); Hussain, A. [Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, UTM Skudai, 81310 Johor (Malaysia); Ahmed, R., E-mail: rashidahmed@utm.my [Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, UTM Skudai, 81310 Johor (Malaysia); Wan Shamsuri, W.N. [Department of Physics, Faculty of Science, Universiti Teknologi Malaysia, UTM Skudai, 81310 Johor (Malaysia); Fu, Y.Q., E-mail: richard.fu@northumbria.ac.uk [Department of Physics and Electrical Engineering, Faculty of Engineering & Environment, University of Northumbria, Newcastle upon Tyne, NE1 8ST (United Kingdom)

    2016-12-30

    Highlights: • A new and novel material for solar cell applications is demonstrated as a replacement for toxic and expansive compounds. • The materials used in this compound are abundant and low cost. • Compound exhibit unusual optical and electrical properties. • The band gap was found to be comparable with that of GaAs. - Abstract: Low price thin film modules based on Copper antimony tin sulphide (CATS) are introduced for solar harvesting to compete for the already developed compound semiconductors. Here, CATS thin films were deposited on soda lime glass by thermal evaporation technique followed by a rapid thermal annealing in an argon atmosphere. From Our XRD analysis, it was revealed that the annealed samples were poly-crystalline and their crystallinity was improved with increasing annealing temperature. The constituent elements and their corresponding chemical states were identified using X-ray photoelectron spectroscopy. The obtained optical band gap of 1.4 eV for CATS thin film is found nearly equal to GaAs – one of the highly efficient thin film material for solar cell technology. Furthermore, our observed good optical absorbance and low transmittance for the annealed CATS thin films in the visible region of light spectrum assured the aptness of the CATS thin films for solar cell applications.

  9. Selective synthesis of ternary copper-antimony sulfide nanocrystals.

    Science.gov (United States)

    Xu, Dongying; Shen, Shuling; Zhang, Yejun; Gu, Hongwei; Wang, Qiangbin

    2013-11-18

    Ternary copper-antimony sulfide nanocrystals (CAS NCs) have attracted increasing attention in photovoltaics and photoelectric nanodevices due to their tunable band gaps in the near-IR regime. Although much progress in the synthesis of CAS NCs has been achieved, the selective synthesis of CAS NCs with controllable morphologies and compositions is preliminary: in particular, a facile method is still in demand. In this work, we have successfully selectively synthesized high-quality CAS NCs with diverse morphologies, compositions, and band gaps, including rectangular CuSbS2 nanosheets (NSs), trigonal-pyramidal Cu12Sb4S13 NCs, and rhombic Cu3SbS3 NSs, by cothermodecomposition of copper diethyldithiocarbamate trihydrate (Cu(Ddtc)2) and antimony diethyldithiocarbamate trihydrate (Sb(Ddtc)3). The direct and indirect band gaps of the obtained CAS NCs were systematically studied by performing Kubelka-Munk transformations of their solid-state diffuse reflectance spectra.

  10. Determination of phosphorus contamination during antimony implantation by measurement and simulation

    International Nuclear Information System (INIS)

    Kuruc, M.; Hulenyi, L.; Kinder, R.

    2006-01-01

    Experimental determination of phosphorus cross-contamination during antimony implantation is presented. As a suitable structure for this experiment, a buried layer was employed which is created by implanting antimony followed by a long diffusion process. The samples implanted in different implanters were analysed by secondary ion mass spectrometry (SIMS), four-point probe and spreading resistance methods. The obtained results were compared with those calculated by program SUPREM-IV. Methods that can and cannot be used to determine phosphorus contamination during antimony implantation and to estimate the fluence of phosphorus being co-implanted with antimony are described in detail

  11. High dose implantations of antimony for buried layer applications

    International Nuclear Information System (INIS)

    Gailliard, J.P.; Dupuy, M.; Garcia, M.; Roussin, J.C.

    1978-01-01

    Electrical and physical properties of high dose implantations of antimony in silicon have been studied for use in buried layer applications. The results have been obtained both on and oriented silicon wafers. Following implantations which lead to amorphization we perform an annealing at 600 0 C for 10 mn in order to recrystallize the layer. The observed electrical properties (μ, R) show that the concentration of electrically active antimony ions is greater than that predicted from the solubility of antimony in silicon. Further annealing (in the range 1050 0 - 1200 0 ) induces: firstly a precipitation of the Sb and secondly a diffusion and dissolution of the precipitates. There is a different evolution of the defects in the and silicon slices. T.E.M. reveals no defects in the wafers after one hour annealing at 1200 0 C, whereas defects and twins remain in wafers. Having obtained the evolution of R with time and temperature it is then determined the implantation and annealing conditions which lead to the low resistivity (R = 10) needed for buried layer applications. Results with very many industrially made devices are discussed

  12. Research on the Characteristics and Mechanism of the Cumulative Release of Antimony from an Antimony Smelting Slag Stacking Area under Rainfall Leaching

    Science.gov (United States)

    Zhou, Yingying; Deng, Renjian

    2017-01-01

    We aimed to study the characteristics and the mechanism of the cumulative release of antimony at an antimony smelting slag stacking area in southern China. A series of dynamic and static leaching experiments to simulate the effects of rainfall were carried out. The results showed that the release of antimony from smelting slag increased with a decrease in the solid-liquid ratio, and the maximum accumulated release was found to be 42.13 mg Sb/kg waste and 34.26 mg Sb/kg waste with a solid/liquid ratio of 1 : 20; the maximum amount of antimony was released within 149–420 μm size fraction with 7.09 mg/L of the cumulative leaching. Also, the antimony release was the greatest and most rapid at pH 7.0 with the minimum release found at pH 4.0. With an increase in rainfall duration, the antimony release increased. The influence of variation in rainfall intensity on the release of antimony from smelting slag was small. PMID:28804669

  13. Antimony leaching from polyethylene terephthalate (PET) plastic used for bottled drinking water.

    Science.gov (United States)

    Westerhoff, Paul; Prapaipong, Panjai; Shock, Everett; Hillaireau, Alice

    2008-02-01

    Antimony is a regulated contaminant that poses both acute and chronic health effects in drinking water. Previous reports suggest that polyethylene terephthalate (PET) plastics used for water bottles in Europe and Canada leach antimony, but no studies on bottled water in the United States have previously been conducted. Nine commercially available bottled waters in the southwestern US (Arizona) were purchased and tested for antimony concentrations as well as for potential antimony release by the plastics that compose the bottles. The southwestern US was chosen for the study because of its high consumption of bottled water and elevated temperatures, which could increase antimony leaching from PET plastics. Antimony concentrations in the bottled waters ranged from 0.095 to 0.521 ppb, well below the US Environmental Protection Agency (USEPA) maximum contaminant level (MCL) of 6 ppb. The average concentration was 0.195+/-0.116 ppb at the beginning of the study and 0.226+/-0.160 ppb 3 months later, with no statistical differences; samples were stored at 22 degrees C. However, storage at higher temperatures had a significant effect on the time-dependent release of antimony. The rate of antimony (Sb) release could be fit by a power function model (Sb(t)=Sb 0 x[Time, h]k; k=8.7 x 10(-6)x[Temperature ( degrees C)](2.55); Sb 0 is the initial antimony concentration). For exposure temperatures of 60, 65, 70, 75, 80, and 85 degrees C, the exposure durations necessary to exceed the 6 ppb MCL are 176, 38, 12, 4.7, 2.3, and 1.3 days, respectively. Summertime temperatures inside of cars, garages, and enclosed storage areas can exceed 65 degrees C in Arizona, and thus could promote antimony leaching from PET bottled waters. Microwave digestion revealed that the PET plastic used by one brand contained 213+/-35 mgSb/kg plastic; leaching of all the antimony from this plastic into 0.5L of water in a bottle could result in an antimony concentration of 376 ppb. Clearly, only a small

  14. Complexation of HSA with different forms of antimony (Sb): An application of fluorescence spectroscopy

    International Nuclear Information System (INIS)

    Song, Wenjuan; Zhang, Daoyong; Pan, Xiangliang; Lee, Duu-Jong

    2013-01-01

    Antimony (Sb) pollution has been of a great environmental concern in some areas in China. Sb enters human body via drinking water, inhalation and food chain, unavoidably interacts with human serum albumin (HSA) in blood plasma, and consequently does harm to human health. The harmful effects of Sb on human health depend on the Sb species and their binding ability to HSA. In the present study, binding of three forms of Sb with HSA was investigated by excitation-emission matrix (EEM) spectroscopy. All of antimony potassium tartrate, antimony trichloride and potassium pyroantimonate quenched fluorescence of HSA. Values of conditional stability constant K a (×10 5 /M) for Sb and HSA systems were 8.13–9.12 for antimony potassium tartrate, 2.51–4.27 for antimony trichloride and 3.63–9.77 for potassium pyroantimonate. The binding constant K b (×10 4 /M) values of HSA with antimony potassium tartrate, antimony trichloride and potassium pyroantimonate were 0.02–0.07, 3.55–5.01, and 0.07–1.08, respectively. There was one independent class of binding site for antimony trichloride towards HSA. There was more than one Sb binding site and negative cooperativity between multiple binding sites for potassium pyroantimonate and antimony potassium tartrate towards HSA. The binding ability of HSA to complex Sb followed the order: antimony trichloride>potassium pyroantimonate>antimony potassium tartrate. -- Highlights: ► The first study reporting interaction of Sb with HSA. ► Sb can effectively quench the fluorescence of HSA. ► The binding ability of HSA to Sb was dependent on the form of Sb. ► Binding differences indicate differences in toxicity of various forms Sb to human. ► HAS-Sb binding parameters are important for understanding toxicity of Sb

  15. Heavy weight vehicle traffic and its relationship with antimony content in human blood.

    Science.gov (United States)

    Quiroz, Waldo; De Gregori, Ida; Basilio, Paola; Bravo, Manuel; Pinto, Marcela; Lobos, Maria Gabriela

    2009-05-01

    Brake pads systems are nowadays considered as one of the most important sources of antimony in airborne particulate matter. One way that antimony can enter the body is through the lungs and specially by the interaction of antimony with -SH groups present in erythrocyte membrane cells. In spite of that, there are no studies about antimony enrichment in blood of workers exposed to high vehicle traffic. Port workers are generally exposed to heavy weight vehicle traffic. In Chile the biggest marine port is found in Valparaíso City. In this study antimony in whole blood and its fractions (erythrocytes-plasma and erythrocytes membranes-cytoplasm) of 45 volunteers were determined. The volunteers were port workers from Valparaíso city, and two control groups, one from Valparaíso and another from Quebrada Alvarado, the latter being a rural area located about 100 Km away from Valparaíso. The results demonstrate that port workers are highly impacted by antimony emissions from heavy weight vehicle traffic showing an average concentration of 27 +/- 9 ng Sb kg(-1), 5-10 times higher than the concentration of antimony in the blood of control groups. These are the highest antimony levels in blood ever reported in the literature. The highest antimony percentages (>60%) were always found in the erythrocyte fractions. However, the exposure degree to vehicle traffic is significant over antimony distribution in plasma, erythrocytes and cytoplasm. This results shows that the antimony mass in the erythrocyte membranes, was approximately constant at 1.0 +/- 0.1 ng Sb g(-1) of whole blood in all blood samples analyzed.

  16. Leishmania donovani isolates with antimony-resistant but not -sensitive phenotype inhibit sodium antimony gluconate-induced dendritic cell activation.

    Directory of Open Access Journals (Sweden)

    Arun Kumar Haldar

    2010-05-01

    Full Text Available The inability of sodium antimony gluconate (SAG-unresponsive kala-azar patients to clear Leishmania donovani (LD infection despite SAG therapy is partly due to an ill-defined immune-dysfunction. Since dendritic cells (DCs typically initiate anti-leishmanial immunity, a role for DCs in aberrant LD clearance was investigated. Accordingly, regulation of SAG-induced activation of murine DCs following infection with LD isolates exhibiting two distinct phenotypes such as antimony-resistant (Sb(RLD and antimony-sensitive (Sb(SLD was compared in vitro. Unlike Sb(SLD, infection of DCs with Sb(RLD induced more IL-10 production and inhibited SAG-induced secretion of proinflammatory cytokines, up-regulation of co-stimulatory molecules and leishmanicidal effects. Sb(RLD inhibited these effects of SAG by blocking activation of PI3K/AKT and NF-kappaB pathways. In contrast, Sb(SLD failed to block activation of SAG (20 microg/ml-induced PI3K/AKT pathway; which continued to stimulate NF-kappaB signaling, induce leishmanicidal effects and promote DC activation. Notably, prolonged incubation of DCs with Sb(SLD also inhibited SAG (20 microg/ml-induced activation of PI3K/AKT and NF-kappaB pathways and leishmanicidal effects, which was restored by increasing the dose of SAG to 40 microg/ml. In contrast, Sb(RLD inhibited these SAG-induced events regardless of duration of DC exposure to Sb(RLD or dose of SAG. Interestingly, the inhibitory effects of isogenic Sb(SLD expressing ATP-binding cassette (ABC transporter MRPA on SAG-induced leishmanicidal effects mimicked that of Sb(RLD to some extent, although antimony resistance in clinical LD isolates is known to be multifactorial. Furthermore, NF-kappaB was found to transcriptionally regulate expression of murine gammaglutamylcysteine synthetase heavy-chain (mgammaGCS(hc gene, presumably an important regulator of antimony resistance. Importantly, Sb(RLD but not Sb(SLD blocked SAG-induced mgammaGCS expression in DCs by

  17. Comparison of modification with strontium and the refining with antimony in A 356 aluminium alloys

    International Nuclear Information System (INIS)

    Fuoco, Ricardo; Correa, Edison Roberto; Correa, Alzira V.O.; Bocalini Junior, Mario

    1992-01-01

    Strontium and Antimony treated A356 aluminium alloy samples were metallographically characterized in the as cast and solution and aged conditions. Antimony treated alloy has shown slower spheroidizing kinetics of the Silicon particles during solution treatment, lower porosity level and higher tensile strength and elongation than Strontium treated one. (author)

  18. Effect of antimony on the microbial growth and the activities of soil enzymes.

    Science.gov (United States)

    An, Youn-Joo; Kim, Minjin

    2009-02-01

    The effects of antimony (Sb) on microbial growth inhibition and activities of soil enzymes were investigated in the present study. Test bacterial species were Escherichia coli, Bacillus subtilis and Streptococcus aureus. Among the microorganisms tested, S. aureus was the most sensitive. The 50% effects on the inhibition of specific growth rate of E. coli, B. subtilis, and, S. aureus were 555, 18.4, and 15.8 mg Sb L(-1), respectively. A silt loam soil was amended with antimony and incubated in a controlled condition. Microbial activities of dehydrogenase, acid phosphatase (P cycle), arylsulfatase (S cycle), beta-glucosidase (C cycle), urease (N cycle), and fluorescein diacetate hydrolase in soil were measured. Activities of urease and dehydrogenase were related with antimony and can be an early indication of antimony contamination. The maximum increase in soil urease activity by antimony was up to 168% after 3d compared with the control. The activities of other four enzymes (acid phosphatase, fluorescein diacetate hydrolase, arylsulfatase and ss-glucosidase) were less affected by antimony. This study suggested that antimony affects nitrogen cycle in soil by changing urease activity under the neutral pH, however, soil enzyme activities may not be a good protocol due to their complex response patterns to antimony pollution.

  19. The Hydrothermal Chemistry of Gold, Arsenic, Antimony, Mercury and Silver

    Energy Technology Data Exchange (ETDEWEB)

    Bessinger, Brad; Apps, John A.

    2003-03-23

    A comprehensive thermodynamic database based on the Helgeson-Kirkham-Flowers (HKF) equation of state was developed for metal complexes in hydrothermal systems. Because this equation of state has been shown to accurately predict standard partial molal thermodynamic properties of aqueous species at elevated temperatures and pressures, this study provides the necessary foundation for future exploration into transport and depositional processes in polymetallic ore deposits. The HKF equation of state parameters for gold, arsenic, antimony, mercury, and silver sulfide and hydroxide complexes were derived from experimental equilibrium constants using nonlinear regression calculations. In order to ensure that the resulting parameters were internally consistent, those experiments utilizing incompatible thermodynamic data were re-speciated prior to regression. Because new experimental studies were used to revise the HKF parameters for H2S0 and HS-1, those metal complexes for which HKF parameters had been previously derived were also updated. It was found that predicted thermodynamic properties of metal complexes are consistent with linear correlations between standard partial molal thermodynamic properties. This result allowed assessment of several complexes for which experimental data necessary to perform regression calculations was limited. Oxygen fugacity-temperature diagrams were calculated to illustrate how thermodynamic data improves our understanding of depositional processes. Predicted thermodynamic properties were used to investigate metal transport in Carlin-type gold deposits. Assuming a linear relationship between temperature and pressure, metals are predicted to predominantly be transported as sulfide complexes at a total aqueous sulfur concentration of 0.05 m. Also, the presence of arsenic and antimony mineral phases in the deposits are shown to restrict mineralization within a limited range of chemical conditions. Finally, at a lesser aqueous sulfur

  20. Metabolism of antimony-124 in lactating dairy cows

    International Nuclear Information System (INIS)

    Bruwaene, R. van; Gerber, G.B.; Kirchmann, R.; Colard, J.

    1982-01-01

    Lactating cows received oral and intravenous administrations of radioactive antimony (III) chloride to study its intestinal and urinary excretion, secretion into milk and organ distribution. Milk samples were taken twice a day and the milk, feces and urine assayed using gamma spectroscopy. Cows administered orally were sacrificed at 102 days and those injected intravenously at 70 days. Distribution of 124 Sb in the organs was determined at the time of sacrifice. Excretion of 124 Sb occurs mainly via urine, little is secreted into milk. Highest organ concentrations are in the spleen, liver and bone. (U.K.)

  1. Electrostatically defined silicon quantum dots with counted antimony donor implants

    Energy Technology Data Exchange (ETDEWEB)

    Singh, M., E-mail: msingh@sandia.gov; Luhman, D. R.; Lilly, M. P. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States); Center for Integrated Nanotechnologies, Sandia National Laboratories, Albuquerque, New Mexico 87175 (United States); Pacheco, J. L.; Perry, D.; Garratt, E.; Ten Eyck, G.; Bishop, N. C.; Wendt, J. R.; Manginell, R. P.; Dominguez, J.; Pluym, T.; Bielejec, E.; Carroll, M. S. [Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

    2016-02-08

    Deterministic control over the location and number of donors is crucial to donor spin quantum bits (qubits) in semiconductor based quantum computing. In this work, a focused ion beam is used to implant antimony donors in 100 nm × 150 nm windows straddling quantum dots. Ion detectors are integrated next to the quantum dots to sense the implants. The numbers of donors implanted can be counted to a precision of a single ion. In low-temperature transport measurements, regular Coulomb blockade is observed from the quantum dots. Charge offsets indicative of donor ionization are also observed in devices with counted donor implants.

  2. Electrical conductivity of uranium-antimony oxide catalysts

    International Nuclear Information System (INIS)

    Golunski, S.E.; Nevell, T.G.; Hucknall, D.J.

    1985-01-01

    The relative ionic and electronic contributions to the electrical conductivity of a uranium-antimony oxide catalyst and of USbO 5 have been determined from measurements of a.c. and d.c. conductance. Under inert atmospheres (390 to 775 K) conduction in the catalyst (predominantly USb 3 O 10 together with small proportions of Sb 2 O 4 and USbO 5 ) is associated with both electronic and effectively charged atomic point defects. Only electronic conduction occurs in USbO 5 . Under oxygen (10 to 70 kPa, 493 to 682 K) both materials are n-type semiconductors at higher temperatures, but at lower temperatures semiconducting behaviour varies with the pressure of oxygen. Heating USbO 5 in oxygen induces an ionic contribution to conductivity. Ionic conduction in the catalyst is eliminated by heating in hydrogen or propene at 470 K but is restored by heating in oxygen. It is suggested that both charged oxygen vacancies and interstitial oxide ions are involved in interactions of gaseous components with uranium-antimony oxides. With alkenes, interstitial oxide ions give rise to the products of selective partial oxidation. (author)

  3. Segregation of antimony in InP in MOVPE

    International Nuclear Information System (INIS)

    Weeke, Stefan

    2008-01-01

    In this work the segregation of antimony in indium phosphide in metal organic vapour phase epitaxy (MOVPE)was systematically investigated. Therefore phosphine stabilized InP surfaces were treated with tri-methyl-antimony (TMSb) in MOVPE. An antimony rich Sb/InP surface was established, showing a typical spectra for the antimonides observed in reflectance anisotropy spectroscopy (RAS).Adsorption and desorption of antimony are investigated, as well as the incorporation of Sb during overgrowth of the Sb/InP surface with InP. Therefore the growth parameters temperature, TMSb partial pressure and treatment time are varied and their influence investigated. The experiments are monitored in-situ with RAS, the achieved data is correlated with ex-situ characterisation such as X-ray diffraction (XRD) and secondary ion mass spectroscopy (SIMS). It is shown that under treatment with TMSb a stable Sb/InP surface is formed within seconds, which does not change under further TMSb treatment. This process is rarely influenced by the TMSb partial pressure. On the contrary, the desorption of Sb is a very slow process. Two main processes can be distinguished: The desorption of excess Sb from the surface and the formation of the MOVPE prepared InP (2 x 1) surface. The reaction velocity of adsorption and desorption increases with temperature. Above a critical value the increase of TMSb partial pressure has no influence on the time for desorption. During overgrowth of the Sb/InP surface the opposite temperature dependence is observed: with increasing growth temperature the typical spectra for antimonides is observed longer. An analysis of the grown samples with XRD and SIMS showed the formation of an InPSb double quantum well. One layer is formed at the interface, the second one 50 nm-120 nm deep in the InP. The location of the 2nd InPSb layer can be correlated with the vanishing of the Sb signature in RAS. The distance between the quantum wells increases with growth temperature, until it

  4. Segregation of antimony in InP in MOVPE

    Energy Technology Data Exchange (ETDEWEB)

    Weeke, Stefan

    2008-07-01

    In this work the segregation of antimony in indium phosphide in metal organic vapour phase epitaxy (MOVPE)was systematically investigated. Therefore phosphine stabilized InP surfaces were treated with tri-methyl-antimony (TMSb) in MOVPE. An antimony rich Sb/InP surface was established, showing a typical spectra for the antimonides observed in reflectance anisotropy spectroscopy (RAS).Adsorption and desorption of antimony are investigated, as well as the incorporation of Sb during overgrowth of the Sb/InP surface with InP. Therefore the growth parameters temperature, TMSb partial pressure and treatment time are varied and their influence investigated. The experiments are monitored in-situ with RAS, the achieved data is correlated with ex-situ characterisation such as X-ray diffraction (XRD) and secondary ion mass spectroscopy (SIMS). It is shown that under treatment with TMSb a stable Sb/InP surface is formed within seconds, which does not change under further TMSb treatment. This process is rarely influenced by the TMSb partial pressure. On the contrary, the desorption of Sb is a very slow process. Two main processes can be distinguished: The desorption of excess Sb from the surface and the formation of the MOVPE prepared InP (2 x 1) surface. The reaction velocity of adsorption and desorption increases with temperature. Above a critical value the increase of TMSb partial pressure has no influence on the time for desorption. During overgrowth of the Sb/InP surface the opposite temperature dependence is observed: with increasing growth temperature the typical spectra for antimonides is observed longer. An analysis of the grown samples with XRD and SIMS showed the formation of an InPSb double quantum well. One layer is formed at the interface, the second one 50 nm-120 nm deep in the InP. The location of the 2nd InPSb layer can be correlated with the vanishing of the Sb signature in RAS. The distance between the quantum wells increases with growth temperature, until it

  5. Removal of arsenic and antimony from anode slime by vacuum dynamic flash reduction.

    Science.gov (United States)

    Lin, Deqiang; Qiu, Keqiang

    2011-04-15

    Anode slime is an important material of recycling precious metals. Up to now, treating the arsenic- and antimony-rich anode slime by conventional processes has the following problems: its economic and environmental effect is less than satisfactory, and the removal effect of arsenic and antimony from anode slime in present processes is not all that could be desired. Therefore, vacuum dynamic flash reduction, a new process for treating arsenic- and antimony-rich anode slime, was investigated in this work. During vacuum dynamic flash reduction, silver from the arsenic- and antimony-rich anode slime was left behind in the distilland as the silver alloy, and trivalent oxides of arsenic and antimony were evaporated in the distillate. The experimental results showed that the evaporation percent of the arsenic- and antimony-rich anode slime was 65.6%. Namely, 98.92% by weight of arsenic and 93.67% by weight of antimony can be removed under the following experimental conditions: temperature of 1083 K, vacuum evaporation time of 60 min, and air flow rate of 400 mL/min corresponding to the residual gas pressure of 250 Pa. Moreover, vacuum treatment eliminates much of the air pollution and material losses associated with other conventional treatment methods.

  6. Immobilization of antimony waste slag by applying geopolymerization and stabilization/solidification technologies.

    Science.gov (United States)

    Salihoglu, Güray

    2014-11-01

    During the processing of antimony ore by pyrometallurgical methods, a considerable amount of slag is formed. This antimony waste slag is listed by the European Union as absolutely hazardous waste with a European Waste Catalogue code of 10 08 08. Since the levels of antimony and arsenic in the leachate of the antimony waste slag are generally higher than the landfilling limits, it is necessary to treat the slag before landfilling. In this study, stabilization/solidification and geopolymerization technologies were both applied in order to limit the leaching potential of antimony and arsenic. Different combinations ofpastes by using Portland cement, fly ash, clay, gypsum, and blast furnace slag were prepared as stabilization/solidification or geopoljymer matrixes. Sodium silicate-sodium hydroxide solution and sodium hydroxide solution at 8 M were used as activators for geopolymer samples. Efficiencies of the combinations were evaluated in terms of leaching and unconfined compressive strength. None of the geopolymer samples prepared with the activators yielded arsenic and antimony leaching below the regulatory limit at the same time, although they yielded high unconfined compressive strength levels. On the other hand, the stabilization/solidification samples prepared by using water showed low leaching results meeting the landfilling criteria. Use of gypsum as an additive was found to be successful in immobilizing the arsenic and antimony.

  7. In Vitro Antiparasitic and Apoptotic Effects of Antimony Sulfide Nanoparticles on Leishmania infantum

    Directory of Open Access Journals (Sweden)

    Saied Soflaei

    2012-01-01

    Full Text Available Visceral leishmaniasis is one of the most important sever diseases in tropical and subtropical countries. In the present study the effects of antimony sulfide nanoparticles on Leishmania infantum in vitro were evaluated. Antimony sulfide NPs (Sb2S5 were synthesized by biological method from Serratia marcescens bacteria. Then the cytotoxicity effects of different concentrations (5, 10, 25, 50, and 100 μg/mL of this nanoparticle were assessed on promastigote and amastigote stages of L. infantum. MTT method was used for verification results of promastigote assay. Finally, the percentages of apoptotic, necrotic, and viable cells were determined by flow cytometry. The results indicated the positive effectiveness of antimony sulfide NPs on proliferation of promastigote form. The IC50 (50% inhibitory concentration of antimony sulfide NPs on promastigotes was calculated 50 μg/mL. The cytotoxicity effect was dose-dependent means by increasing the concentration of antimony sulfide NPs, the cytotoxicity curve was raised and the viability curve of the parasite dropped simultaneously. Moreover, the IC50 of antimony sulfide NPs on amastigote stage was calculated 25 μg/mL. On the other hand, however, antimony sulfide NPs have a low cytotoxicity effect on uninfected macrophages but it can induce apoptosis in promastigote stage at 3 of 4 concentrations.

  8. The potential DNA toxic changes among workers exposed to antimony trioxide.

    Science.gov (United States)

    El Shanawany, Safaa; Foda, Nermine; Hashad, Doaa I; Salama, Naglaa; Sobh, Zahraa

    2017-05-01

    Occupational exposure to antimony has gained much interest when specific toxic effects were noticed among workers processing antimony. Thus, the aim of the present work was to investigate the potential DNA oxidative damage occurring among Egyptian workers occupationally exposed to antimony trioxide. The study was conducted on 25 subjects exposed to antimony trioxide while working in the polymerization process of polyester in Misrayon and Polyester Fiber Company, KafrEldawwar, Beheira, Egypt. Urinary antimony levels were assessed using inductive coupled plasma-optical emission spectrometry (ICP-OES) and considered as a biological exposure index. DNA damage and total oxidant capacity (TOC) were assessed using ELISA. DNA damage was detected in the form of increased apurinic/apyrimidinic (AP) sites among antimony trioxide-exposed workers compared to control subjects, but it could not be explained by oxidative mechanisms due to lack of significant correlation between DNA damage and measured TOC. Antimony trioxide might have a genotoxic impact on occupationally exposed workers which could not be attributed to oxidative stress in the studied cases.

  9. Nuclear resonance scattering study of iridates, iridium and antimony based pyrochlores

    Energy Technology Data Exchange (ETDEWEB)

    Alexeev, P.

    2017-04-15

    on Ir nucleus have been determined for these compounds. In order to broaden the perspectives of NRS with the 73 keV resonance the first room temperature NRS on iridium metal is carried out. The results demonstrate NRS as a powerful research tool for the studies of iridium physics due to the high energy of the resonant photons and the high natural abundance of the {sup 193}Ir isotope under study, paving the way for studies of magnetism and electronic properties under extreme conditions. The second part of this work is dedicated to vibrational spectroscopy with Nuclear Inelastic Scattering (NIS). A sapphire backscattering monochromator was designed, installed and tested at the beamline. It provides high energy resolution due to the sub-mK temperature control, though the resolution is limited from theoretically proposed sub-meV to meV by the quality of currently available sapphire crystals. With this device the energy resolution of 1.3(1) meV at 23.88 keV and of 3.2(4) meV at 37.13 keV was achieved. Following this development, the vibrational spectra of antimony in defect pyrochlore Ag-Sb-O compounds have been measured by means of NIS at 37.13 keV. Density of phonon states for the Sb(III) and for the Sb(V) site has been unambiguously revealed. The difference in site-specific antimony modes illustrates the importance of lattice dynamics for the engineering of these compounds.

  10. Nuclear resonance scattering study of iridates, iridium and antimony based pyrochlores

    International Nuclear Information System (INIS)

    Alexeev, P.

    2017-04-01

    these compounds. In order to broaden the perspectives of NRS with the 73 keV resonance the first room temperature NRS on iridium metal is carried out. The results demonstrate NRS as a powerful research tool for the studies of iridium physics due to the high energy of the resonant photons and the high natural abundance of the 193 Ir isotope under study, paving the way for studies of magnetism and electronic properties under extreme conditions. The second part of this work is dedicated to vibrational spectroscopy with Nuclear Inelastic Scattering (NIS). A sapphire backscattering monochromator was designed, installed and tested at the beamline. It provides high energy resolution due to the sub-mK temperature control, though the resolution is limited from theoretically proposed sub-meV to meV by the quality of currently available sapphire crystals. With this device the energy resolution of 1.3(1) meV at 23.88 keV and of 3.2(4) meV at 37.13 keV was achieved. Following this development, the vibrational spectra of antimony in defect pyrochlore Ag-Sb-O compounds have been measured by means of NIS at 37.13 keV. Density of phonon states for the Sb(III) and for the Sb(V) site has been unambiguously revealed. The difference in site-specific antimony modes illustrates the importance of lattice dynamics for the engineering of these compounds.

  11. Synthesis, characterisation and electrochemical evaluation of reduced graphene oxide modified antimony nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Silwana, Bongiwe; Horst, Charlton van der [Natural Resources and the Environment (NRE), Council for Scientific and Industrial Research (CSIR), Stellenbosch 7600 (South Africa); SensorLab, Department of Chemistry, University of the Western Cape, Bellville 7535 (South Africa); Iwuoha, Emmanuel [SensorLab, Department of Chemistry, University of the Western Cape, Bellville 7535 (South Africa); Somerset, Vernon, E-mail: vsomerset@csir.co.za [Natural Resources and the Environment (NRE), Council for Scientific and Industrial Research (CSIR), Stellenbosch 7600 (South Africa)

    2015-10-01

    This paper demonstrates some aspects on the synthesis and characterisation of nanoparticles of metallic alloys using polyvinyl alcohol as a stabiliser, which combines high surface area and superior hybrid properties. The present experimental design was to synthesise a nanocomposite of reduced graphene oxide and antimony nanoparticles to be used as thin films for macro- and micro-carbon electrodes for enhancing sensing of different toxic metal pollutants in the environment. The synthetic process of reduced graphene oxide was done using the modified Hummers method while antimony pentachloride was reduced with sodium borohydride into nanoparticles of antimony using polyvinyl-alcohol as a stabiliser. The systematic investigation of morphology was done by scanning electron microscopy and high resolution-transmission electron microscope, which revealed the synthesis of a product, consists of reduced graphene oxide antimony nanoparticles. The electrochemical behaviour of the reduced graphene oxide antimony nanoparticles coated on a glassy carbon electrode was performed using voltammetric and impedance techniques. Electrochemical impedance measurements showed that the overall resistance, including the charge–transfer resistance, was smaller with reduced graphene oxide antimony nanoparticles than reduced graphene oxide and antimony nanoparticles, on their own. Evaluation of the reduced graphene oxide antimony nanoparticle sensor in the stripping voltammetry has shown a linear working range for concentration of platinum (II) between 6.0 × 10{sup −6}–5.4 × 10{sup −5} μg L{sup −1} with limit of detection of 6 × 10{sup −6} μg L{sup −1} (signal-to-noise ratio = 3), which is below the World Health Organisation guidelines for freshwater. - Highlights: • Reduced graphene oxide modified antimony nanoparticles were chemically synthesised. • TEM results show rGO-Sb nanoparticles with a diameter range of between 2 and 20 nm. • Impedance results confirm

  12. Silicon quantum dots with counted antimony donor implants

    Science.gov (United States)

    Singh, Meenakshi; Pacheco, Jose; Perry, Daniel; Wendt, Joel; Manginell, Ronald; Dominguez, Jason; Pluym, Tammy; Luhman, Dwight; Bielejec, Edward; Lilly, Michael; Carroll, Malcolm

    Antimony donor implants next to silicon quantum dots have been detected with integrated solid-state diode detectors with single ion precision. Devices with counted number of donors have been fabricated and low temperature transport measurements have been performed. Charge offsets, indicative of donor ionization and coupling to the quantum dot, have been detected in these devices. The number of offsets corresponds to 10-50% of the number of donors counted. We will report on tunneling time measurements and spin readout measurements on the donor offsets. This work was performed, in part, at the Center for Integrated Nanotechnologies, a U.S. DOE Office of Basic Energy Sciences user facility. The work was supported by Sandia National Laboratories Directed Research and Development Program. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the U. S. Department of Energy under Contract No. DE-AC04-94AL85000.

  13. Calcium metal as a scavenger for antimony from aluminum alloys

    Energy Technology Data Exchange (ETDEWEB)

    Bonsignore, P.V.; Daniels, E.J.; Wu, C.T.

    1994-10-04

    Previous work has shown that trace amounts of antimony (Sb) can affect the mechanical properties of strontium (Sr) modified aluminum castings. ANL has been investigating technology to remove or neutralize Sb to reduce its negative effect on the physical properties of those alloys. Review of past work on processing and recovery of scrap aluminum inferred that calcium (Ca) is an effective scavenger of Sb, bismuth, lead and cadmium. Following up on that lead, we have found that Ca is, indeed, effective for removing Sb from molten aluminum alloys although its effectiveness can be compromised by a wide range of processing conditions. A minimum ratio of about four to one, by weight, of Ca to Sb appears necessary to insure an effective scavenging of contained Sb.in 356 aluminum alloys.

  14. Antimony Accumulation Risk in Lettuce Grown in Brazilian Urban Gardens

    Directory of Open Access Journals (Sweden)

    Silvia Mancarella

    2016-08-01

    Full Text Available More than 80% of the Brazilian population inhabits urban areas. Diffused poverty and the lack of fresh vegetables have generated malnutrition and unbalanced diets. Thus, the interest in growing food locally, in urban allotments and community gardens, has increased. However, urban agriculture may present some risks caused by the urban pollution. Road traffic is considered the biggest source of heavy metals in urban areas. Hence, the objective of the study was the assessment of the accumulation of heavy metals in an urban garden in the city of Recife, at different distances from a road with high traffic burden. The results showed that the distance from the street decreased the accumulation of many potentially toxic elements. Furthermore, the human health risk was estimated, revealing that greater danger was associated with the accumulation of antimony. Concentration of other elements in the leaf tissues were within previously reported thresholds.

  15. Comparative study of hematological responses to platinum group metals, antimony and silver nanoparticles in animal models.

    Science.gov (United States)

    Newkirk, Catherine E; Gagnon, Zofia E; Pavel Sizemore, Ioana E

    2014-01-01

    Research was conducted to examine the hematological effects of heavy metals (platinum (Pt ((IV))), palladium (Pd ((II))), rhodium (Rh ((III))), antimony (Sb ((III)) and Sb ((V))), and silver nanoparticles (AgNPs)) on white blood cells in mammalian (rat) and avian (chick embryo) models. These metals are used in many everyday products and are accumulating in our environment. Six-week old Sprague-Dawley female rats were treated daily by gavage and six-day old, fertile, specific pathogen-free white leghorn strain chick embryos' eggs were injected on days 7 and 14 of incubation with 0.0, 1.0, 5.0 or 10.0 ppm concentrations of Pt ((IV)) and a platinum group metal (PGM) mix of Pt ((IV)), Pd ((II)) and Rh ((III)). Chick embryos were also tested with 1.0 or 5.0 ppm of antimony compounds (Sb ((III)) and Sb ((V))) and 0.0, 15.0, 30.0, 60.0, or 100.0 ppm of silver nanoparticles (AgNPs). After 8 weeks of treatment, blood was obtained from the rats by jugular cut down and from chick embryos on day 20 of incubation by heart puncture. Blood smears were made and stained and a differential white cell count was performed on each. Examination of the smears revealed unconventional dose responses, stimulation of the immune response, and decreases in leukocyte production with various metals and concentrations. Chick embryos responded differently than rats to Pt and the PGM mix; suggesting that species differences and/or stage of development are important components of response to heavy metals. Route of administration of the metals might also influence the response. All of the heavy metals tested affected the immune responses of the tested animals as demonstrated by changes in the types and numbers of leukocytes. Our findings warrant further research to determine the mechanism of these effects and to understand and prevent toxicological effects in humans and other living organisms.

  16. Antimony as a global dilemma: Geochemistry, mobility, fate and transport.

    Science.gov (United States)

    Herath, Indika; Vithanage, Meththika; Bundschuh, Jochen

    2017-04-01

    Elevated concentrations of antimony (Sb) in environmental, biological and geochemical systems originating from natural, geological and anthropogenic sources are of particular global concern. This review presents a critical overview of natural geochemical processes which trigger the mobilization of Sb from its host mineral phases and related rocks to the surrounding environments. The primary source of Sb contamination in the environment is geogenic. The geochemical characteristics of Sb are determined by its oxidation states, speciation and redox transformation. Oxidative dissolution of sulfide minerals and aqueous dissolution are the most prevalent geochemical mechanisms for the release of Sb to the environment. Transformation of mobile forms of Sb is predominantly controlled by naturally occurring precipitation and adsorption processes. Oxyhydroxides of iron, manganese and aluminum minerals have been recognized as naturally occurring Sb sequestrating agents in the environment. Antimony is also immobilized in the natural environment via precipitation with alkali and heavy metals resulting extremely stable mineral phases, such as schafarzikite, tripuhyite and calcium antimonates. Many key aspects, including detection, quantification, and speciation of Sb in different environmental systems as well as its actual human exposure remain poorly understood. Identification of global distribution of most vulnerable Sb-contaminated regions/countries along with aquifer sediments is an urgent necessity for the installation of safe drinking water wells. Such approaches could provide the global population Sb-safe drinking and irrigation water and hinder the propagation of Sb in toxic levels through the food chain. Hence, raising awareness through the mobility, fate and transport of Sb as well as further transdisciplinary research on Sb from global scientific communities will be a crucial stage to establish a sustainable Sb mitigation on a global scale. Copyright © 2017 Elsevier

  17. NEW THIO S2- ADDUCTS WITH ANTIMONY (III AND V HALIDE: SYNTHESIS AND INFRARED STUDY

    Directory of Open Access Journals (Sweden)

    HASSAN ALLOUCH

    2013-12-01

    Full Text Available Five new S2- adducts with SbIII and SbV halides have been synthesized and studied by infrared. Discrete structures have been suggested, the environment around the antimony being tetrahedral, trigonal bipyramidal or octahedral.

  18. Antimony-based focal plane arrays for shortwave-infrared to visible applications, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop antimony-based focal plane arrays (FPAs) for NASA's imaging and spectroscopy applications in the spectral band from visible to...

  19. Antimony-Based Focal Plane Arrays for Shortwave-Infrared to Visible Applications, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop antimony-based focal plane arrays (FPAs) for NASA's imaging and spectroscopy applications in the spectral band from visible to...

  20. Liquid-liquid extraction of arsenic, antimony, selenium and tellurium by zinc diethyldithiocarbamate

    International Nuclear Information System (INIS)

    Bajo, S.; Wyttenbach, A.

    1978-03-01

    The authors report the solvent extraction, oxidation, reduction, extraction in the presence of iron, and reextraction of arsenic, antimony, selenium and tellurium. These processes were studied using radioactive tracers. (G.T.H.)

  1. Exposure to antimony from polyethylene terephthalate (PET) trays used in ready-to-eat meals.

    Science.gov (United States)

    Haldimann, M; Blanc, A; Dudler, V

    2007-08-01

    Antimony residues, a result of the use of a polycondensation catalyst in the production of polyethylene terephthalate (PET) oven-proof trays, were analysed in ready-to-eat meals. The toxicity of antimony has raised concerns about consumer safety; therefore, the migration of small fractions of these residues into ready meals and foods as a result of cooking directly in the PET trays was studied. A straightforward approach of measuring real samples was selected to obtain accurate exposure data. Background antimony concentration was determined separately from a series of lunch meals, which ranged from not detectable to 3.4 microg kg(-1). Microwave and conventional oven-cooking caused a distinct increase in the concentration of antimony in food and ready meals of 0-17 and 8-38 microg kg(-1), respectively, depending, to a certain extent, on the industrial preparations. The migrated quantities of antimony corresponded to 3-13 microg. For comparison, PET roasting bags and ready-made dough products in PET baking dishes were also evaluated. About half of the products prepared at a temperature of 180 degrees C exceeded the specific migration limit set for food contact material by the European Commission. However, the migrated amounts of antimony relative to the accepted tolerable daily intake (TDI) show that exposure from this type of food is currently not of toxicological concern.

  2. Simulation of antimony adsorption on nano-zero valent iron and kaolinite and analyzing the influencing parameters.

    Science.gov (United States)

    Saeidnia, Setareh; Asadollahfardi, Gholamreza; Darban, Ahmad Khodadadi; Mohseni, Mehdi

    2016-01-01

    Antimony is one of the most toxic pollutants in industrial and mineral wastewaters threatening the life of humans and other creatures. We simulated the adsorption of antimony in the presence of nano-zero valent iron (nZVI) adsorbent, on kaolinite and in the presence of nZVI coated on kaolinite from mineral wastewater using VISUAL MINTEQ 3.1 software. Our aim was to determine the factors affecting the adsorption of antimony by applying simulation. The simulation was performed using an adsorption model of a diffuse layer model. The results of the simulation indicated that the nZVI concentration, initial concentrations of antimony and pH factor are effective on the adsorption of antimony. In the conducted stimulation, the optimum pH was 2-5 and the highest adsorption occurred in an acidic state. With increasing initial concentrations of antimony in the simulation, we concluded that nZVI had absorbed various concentrations above 90% and, by increasing the concentration of nZVI, antimony adsorption rate increased. The increased surface area of nZVI and the expansion of more interchangeable surfaces available for reaction with antimony ions causes more antimony ions to be adsorbed. In all cases, the coefficient of determination between the laboratory results and the model predictions that was obtained was more than 0.9.

  3. New fluorescent polymeric nanocomposites synthesized by antimony dodecyl-mercaptide thermolysis in polymer

    Directory of Open Access Journals (Sweden)

    2009-04-01

    Full Text Available In this work, the formation of semiconductive Sb2S3 nanoparticles inside amorphous polystyrene has been achieved by thermal degradation of the corresponding antimony dodecyl-mercaptide, Sb(SC12H253. The thermolysis of the dodecyl-mercaptide precursor was studied as both pure phase and mercaptide solution in polystyrene. The thermal decomposition of the antimony mercaptide precursor at 350°C, under vacuum, showed the formation of a mixture of antimony trisulfide (stibnite, Sb2S3 and zero-valent antimony (Sb phase. X-ray Powder Diffraction (XRD and Rietveld analysis carried out on the obtained nanostructured powder confirmed the presence of Sb and Sb2S3 phases in 10.4 wt% and 89.6 wt% amount, respectively. The same pyrolysis reaction was carried out in the polymer and the resulting nanocomposite material was characterized by X-ray diffraction (XRD, transmission electron microscopy (TEM, UV-VIS spectroscopy, and fluorescence spectroscopy. The nanocomposite structural characterization indicated the presence of well-dispersed nanoclusters of antimony and stibnite (15–30 nm in size inside the amorphous polymeric phase. Optical measurements on the obtained nanocomposite films showed a strong emission at 432 nm upon excitation at 371 nm, probably related to the presence of Sb2S3 nanoclusters.

  4. Predictors of an unsatisfactory response to pentavalent antimony in the treatment of American visceral leishmaniasis

    Directory of Open Access Journals (Sweden)

    Santos Mácia A.

    2002-01-01

    Full Text Available Although treatment of visceral leishmaniasis with pentavalent antimony is usually successful, some patients require second-line drug therapy, most commonly with amphotericin B. To identify the clinical characteristics that predict an inadequate response to pentavalent antimony, a case-control study was undertaken in Teresina, Piaui, Brazil. Over a two-year period, there were 19 cases of VL in which the staff physicians of a hospital prescribed second-line therapy with amphotericin B after determining that treatment with pentavalent antimony had failed. The control group consisted of 97 patients that were successfully treated with pentavalent antimony. A chart review using univariate and multivariate analysis was performed. The cure rate was 90% with amphotericin B. The odds ratio for the prescription of amphotericin B was 10.2 for children less than one year old, compared with individuals aged over 10 years. Patients who presented coinfection had an OR of 7.1 while those on antibiotics had an OR of 2.8. These data support either undertaking a longer course of therapy with pentavalent antimony for children or using amphotericin B as a first-line agent for children and individuals with coinfections. It also suggests that chemoprophylaxis directed toward bacterial coinfection in small children with VL may be indicated.

  5. A comparative study of antimony accumulation in plants growing in two mining areas in Iran, Moghanlo, and Patyar

    NARCIS (Netherlands)

    Hajiani, N.J.; Ghaderian, S.M.; Karimi, N.; Schat, H.

    2015-01-01

    Antimony occurs locally at high concentrations in some mineralized soils. Very little is known about behavior of antimony in plants. In this study, we analyzed the soil and vegetation of two mining areas in Iran, Patyar, and Moghanlo. Total Sb concentrations in soil were 358–3482 mg/kg in Moghanlo

  6. New antimony(III) halide complexes with dithiocarbamate ligands derived from thiuram degradation: The effect of the molecule's close contacts on in vitro cytotoxic activity

    Energy Technology Data Exchange (ETDEWEB)

    Urgut, O.S. [Department of Chemistry, Namık Kemal University, 59030, Tekirdag (Turkey); Ozturk, I.I., E-mail: iiozturk@nku.edu.tr [Department of Chemistry, Namık Kemal University, 59030, Tekirdag (Turkey); Banti, C.N., E-mail: cbanti@cc.uoi.gr [Section of Inorganic and Analytical Chemistry, Department of Chemistry, University of Ioannina, 45110 Ioannina (Greece); Kourkoumelis, N., E-mail: nkourkou@uoi.gr [Medical Physics Laboratory, Medical School, University of Ioannina, Ioannina, 45110 (Greece); Manoli, M.; Tasiopoulos, A.J. [Department of Chemistry, University of Cyprus, Nicosia (Cyprus); Hadjikakou, S.K., E-mail: shadjika@uoi.gr [Section of Inorganic and Analytical Chemistry, Department of Chemistry, University of Ioannina, 45110 Ioannina (Greece)

    2016-01-01

    ABSTRACT: Antimony(III) halide complexes of the formulae {[SbBr(Me_2DTC)_2]_n} (1), {[SbI(Me_2DTC)_2]_n} (2) and {[(Me_2DTC)_2Sb(μ_2-I)Sb(Me_2DTC)_2]"+.I_3"−} (3) (Me{sub 2}DTC = dimethyldithiocarbomate) were synthesized from SbX{sub 3}, (X = Br or I) and tetramethylthiuram monosulfide (Me{sub 4}tms) or tetramethylthiuram disulfide (Me{sub 4}tds). The complexes were characterized by melting point (m.p.), elemental analysis (e.a.), Fourier-transform Infra-Red (FT-IR), Fourier-transform Raman (FT-Raman), Nuclear Magnetic Resonance ({sup 1}H,{sup 13}C-NMR) spectroscopy and Thermogravimetric-Differential Thermal Analysis (TG-DTA). Crystal structures of complexes 1–3 were determined with single crystal X-ray diffraction analysis. Complexes 1 and 2 are polymers with distorted square pyramidal (SP) geometry in each monomeric unit, whereas complex 3 is ionic, containing an iodonium linkage Sb–I{sup +}–Sb and an I{sub 3}{sup −} counter anion; to the best of our knowledge, this is the first ionic antimony(III) iodide complex. The in vitro cytotoxic activity of 1–3 against human adenocarcinoma cells: breast (MCF-7) and cervix (HeLa) cells and non-cancerous cells: MRC-5 (normal human fetal lung fibroblast cells) was evaluated with trypan blue (TB) and sulforhodamine B (SRB) assays. Among antimony(III) compounds with sulfur containing ligand, those of dithiocarbamates exhibit significant cytotoxic activity. Hirshfeld surface volumes were analyzed to clarify the nature of the intermolecular interactions by the 2D fingerprint plot. Molecules with lower H-all atoms inter-molecular interactions exhibit the higher activity against MCF-7 cells. The in vivo genotoxicity of 1–3 was evaluated by the mean of Allium cepa test. Alterations in the mitotic index values due to the chromosomal aberrations were observed in the case of complexes 2 and 3. Since, no such alteration is caused by 1, it makes this compound candidate for further study as potential drug. - Graphical

  7. Experimental and theoretical investigation of the chromium-vanadium-antimony system

    Energy Technology Data Exchange (ETDEWEB)

    Regus, Matthias; Bensch, Wolfgang [Kiel Univ. (Germany). Inst. of Inorganic Chemistry; Polesya, Svitlana; Kuhn, Gerhard; Mankovsky, Sergiy; Ebert, Hubert [Muenchen Univ. (Germany). Dept. of Chemistry; Bauers, Sage R.; Johnson, David C. [Oregon Univ., Eugene, OR (United States). Dept. of Chemistry

    2017-03-01

    The binary compound V{sub 3}Sb (V{sub 2.64}Sb, V{sub 3}Sb and V{sub 3.24}Sb) was synthesized as thin multilayered films with varying V:Sb ratios. The V-content determines the crystallization temperature and it is highest for the film with the lowest amount of V. Ternary chromium-vanadium-antimony (Cr-V-Sb) films were prepared containing Cr from 10 to 51 at-% with the Sb content fixed to yield M{sub 3}Sb (M=Cr, V). In the as-deposited state the layers are already interdiffused which is most likely caused by the very low repeating unit thickness between 0.29 and 0.68 nm investigated by X-ray diffraction experiments. All ternary compounds crystallized from the amorphous state with crystallization temperatures depending more on the repeating unit thickness than on chemical composition. For most samples the simultaneous crystallization of the two phases M{sub 3}Sb (A15 structure type) and MSb is observed. The crystalline A15 compounds are only stable in a limited temperature range and decompose at elevated temperatures. Compared to the binary Cr-Sb system crystallization of the hexagonal phase MSb (M=Cr, V) occurs at remarkably higher temperatures, i.e. in the ternary system nucleation and crystallization of this phase is hindered. The chemical composition requires short-range composition fluctuations to nucleate the binary phase. The first principles total energy calculations using the spin-polarized relativistic Korringa-Kohn-Rostoker (SPR-KKR) method confirm the experimental observations concerning the concentration-dependent stability of different phases of the Cr-V-Sb system. For the ratio M:Sb=3:1 the system is preferably stabilized in the A15 crystal structure for all possible Cr and V concentrations, while an increase of Sb content up to M:Sb=2:1 results in the stabilization of the Ni{sub 2}In structure for almost all Cr concentrations. Only in the V-rich regime of the system the Heusler Ni{sub 2}MnAl-type structure was found to be energetically more preferable.

  8. Study of upscaling possibilities for antimony sulfide solid state sensitized solar cells

    Science.gov (United States)

    Nikolakopoulou, Archontoula; Raptis, Dimitrios; Dracopoulos, Vasilios; Sygellou, Lamprini; Andrikopoulos, Konstantinos S.; Lianos, Panagiotis

    2015-03-01

    Solid state solar cells of inverted structure were constructed by successive deposition of nanoparticulate titania, antimony sulfide sensitizer and P3HT on FTO electrodes with PEDOT:PSS:Ag as counter electrode. Sensitized photoanode electrodes were characterized by XRD, Raman, XPS, FESEM and UV-vis. Small laboratory scale cells were first constructed and optimized. Functional cells were obtained by annealing the antimony sulfide film either in air or in inert atmosphere. High short-circuit currents were recorded in both cases with air-annealed sample producing more current but lower voltage. Small unit cells were combined to form cell modules. Connection of unit cells in parallel increased current but not proportionally to that of the unit cell. Connection in series preserved current and generated voltage multiplication. Cells were constructed and studied under ambient conditions, without encapsulation. The results encourage upscaling of antimony sulfide solar cells.

  9. Anodic stripping voltammetry of antimony using gold nanoparticle-modified carbon screen-printed electrodes

    International Nuclear Information System (INIS)

    Dominguez Renedo, Olga; Arcos Martinez, M. Julia

    2007-01-01

    Carbon screen-printed electrodes (CSPE) modified with gold nanoparticles present an interesting alternative in the determination of antimony using differential pulse anodic stripping voltammetry. Metallic gold nanoparticles deposits have been obtained by direct electrochemical deposition. Scanning electron microscopy measurements show that the electrochemically synthesized gold nanoparticles are deposited in aggregated form. Any undue effects caused by the presence of foreign ions in the solution were also analyzed to ensure that common interferents in the determination of antimony by ASV. The detection limit for Sb(III) obtained was 9.44 x 10 -10 M. In terms of reproducibility, the precision of the above mentioned method in %R.S.D. values was calculated at 2.69% (n = 10). The method was applied to determine levels of antimony in seawater samples and pharmaceutical preparations

  10. Conceptual design for treatment of mining and metallurgical wastewaters which contains arsenic and antimony

    Directory of Open Access Journals (Sweden)

    Željko Kamberović

    2012-12-01

    Full Text Available This paper presents a preliminary design for treatment of mining and metallurgical wastewaters (MMW from the basin of antimony “Zajača“, which contains high concentrations of arsenic and antimony. MMW have been investigated in laboratory, due to large difference in concentrations of pollutants. Metallurgical wastewaters were treated using iron (II-sulfate and lime milk used to adjust the pH value at 7. After chemical treatment of metallurgical wastewater and its joining with mining wastewater, residual amount of arsenic in water was below maximum allowed concentrations, while the concentration of antimony, remained above the maximum allowed value. The final phase of purification process was performed using ion exchange resin. After treatment of MMW, they can be used as technical water in the smelting process of secondary raw lead materials.

  11. Enhanced Photoelectrochemical Response from Copper Antimony Zinc Sulfide Thin Films on Transparent Conducting Electrode

    Directory of Open Access Journals (Sweden)

    Prashant K. Sarswat

    2013-01-01

    Full Text Available Copper antimony sulfide (CAS is a relatively new class of sustainable absorber material, utilizing cost effective and abundant elements. Band gap engineered, modified CAS thin films were synthesized using electrodeposition and elevated temperature sulfurization approach. A testing analog of copper zinc antimony sulfide (CZAS film-electrolyte interface was created in order to evaluate photoelectrochemical performance of the thin film of absorber materials. Eu3+/Eu2+ redox couple was selected for this purpose, based on its relative band offset with copper antimony sulfide. It was observed that zinc has a significant effect on CAS film properties. An enhanced photocurrent was observed for CAS film, modified with zinc addition. A detailed investigation has been carried out by changing stoichiometry, and corresponding surface and optical characterization results have been evaluated. A summary of favorable processing parameters of the films showing enhanced photoelectrochemical response is presented.

  12. Genotoxicity studies of heavy metals: lead, bismuth, indium, silver and antimony.

    Science.gov (United States)

    Asakura, Keiko; Satoh, Hiroshi; Chiba, Momoko; Okamoto, Masahide; Serizawa, Koji; Nakano, Makiko; Omae, Kazuyuki

    2009-01-01

    Many kinds of heavy metals are used in industry; thus, it is important for us to clarify their toxicity. For example, lead, which is a component of solder, is notorious for its neurotoxicity, and substitute materials have been sought for many years. Therefore, we examined the genotoxicity of lead and also those of metallic bismuth, indium, silver and antimony which are possible substitutes for lead in solder. Bacterial reverse mutation tests and chromosomal aberration tests in cultured mammalian cells were performed according to standard procedures. Antimony showed genotoxicity in both tests, and bismuth also showed positive results in the chromosomal aberration test. In contrast, lead, indium, and silver were considered to be inactive by the criteria of the present study. Although further studies are needed because of the difficulty of genotoxicity evaluation using an in vitro system, sufficient precautions should be made when antimony and bismuth are used.

  13. Synthesis and characterisation of tin and antimony nano-compounds for lithium battery applications

    NARCIS (Netherlands)

    Simonin, L.

    2009-01-01

    The growing interest during the past decades for mobile devices, like laptops, cellular phones, MP3 players, etc., is impressive. moreover, the concerns about climate changes have increased the worldwide interest for electrical and hybrid vehicles and intermittent sustainable energies, like solar

  14. On-line lab-in-syringe cloud point extraction for the spectrophotometric determination of antimony.

    Science.gov (United States)

    Frizzarin, Rejane M; Portugal, Lindomar A; Estela, José M; Rocha, Fábio R P; Cerdà, Victor

    2016-02-01

    Most of the procedures for antimony determination require time-consuming sample preparation (e.g. liquid-liquid extraction with organic solvents), which are harmful to the environment. Because of the high antimony toxicity, a rapid, sensitive and greener procedure for its determination becomes necessary. The goal of this work was to develop an analytical procedure exploiting for the first time the cloud point extraction on a lab-in-syringe flow system aiming at the spectrophotometric determination of antimony. The procedure was based on formation of an ion-pair between the antimony-iodide complex and H(+) followed by extraction with Triton X-114. The factorial design showed that the concentrations of ascorbic acid, H2SO4 and Triton X-114, as well as second and third order interactions were significant at the 95% confidence level. A Box-Behnken design was applied to obtain the response surfaces and to identify the critical values. System is robust at the 95% confidence level. A linear response was observed from 5 to 50 µg L(-1), described by the equation A=0.137+0.050C(Sb) (r=0.998). The detection limit (99.7% confidence level), the coefficient of variation (n=5; 15 µg L(-1)) and the sampling rate was estimated at 1.8 µg L(-1), 1.6% and 16 h(-1), respectively. The procedure allows quantification of antimony in the concentrations established by environmental legislation (6 µg L(-1)) and it was successfully applied to the determination of antimony in freshwater samples and antileishmanial drugs, yielding results in agreement with those obtained by HGFAAS at the 95% confidence level. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Purity and crystallinity of microwave synthesized antimony sulfide microrods

    Energy Technology Data Exchange (ETDEWEB)

    Martínez-Alonso, Claudia, E-mail: claudiamartinezalonso30@gmail.com [Facultad de Química, Universidad Autónoma de Querétaro, Querétaro, Querétaro, 76010 (Mexico); Olivos-Peralta, Eliot U. [Instituto de Energías Renovables, Universidad NacionalAutónoma de México, Temixco, Morelos, 62580 (Mexico); Sotelo-Lerma, Mérida [Universidad de Sonora, Hermosillo, Sonora, 83000 (Mexico); Sato-Berrú, Roberto Y. [Centro de Ciencias Aplicadas y Desarrollo Tecnológico, Universidad Nacional Autónoma de México, MéxicoD.F., 04510 (Mexico); Mayén-Hernández, S.A. [Facultad de Química, Universidad Autónoma de Querétaro, Querétaro, Querétaro, 76010 (Mexico); Hu, Hailin, E-mail: hzh@ier.unam.mx [Instituto de Energías Renovables, Universidad NacionalAutónoma de México, Temixco, Morelos, 62580 (Mexico)

    2017-01-15

    Antimony sulfide (Sb{sub 2}S{sub 3}) is a promising semiconductor material for solar cell applications. In this work, microrods of Sb{sub 2}S{sub 3} were synthesized by microwave heating with different sulfur sources, solvents, temperature, heating rate, power, and solution concentration. It was found that 90% of stoichiometric Sb{sub 2}S{sub 3} can be obtained with thiourea (TU) or thioacetamide (TA) as sulfur sources and that their optical band gap values were within the range of 1.59–1.60 eV. The most crystalline Sb{sub 2}S{sub 3} were obtained by using TU. The morphology of the Sb{sub 2}S{sub 3} with TU the individual rods were exhibited, whereas rods bundles appeared in TA-based products. The solvents were ethylene glycol (EG) and dimethylformamide (DMF). EG generates more heat than DMF during the microwave synthesis. As a result, the Sb{sub 2}S{sub 3} obtained with EG contained a larger percentage of oxygen and smaller crystal sizes compared to those from DMF. On the other hand, the length and diameter of Sb{sub 2}S{sub 3} microrods can be increased by applying higher heating power although the crystal size did not change at all. In summary, pure and highly crystalline Sb{sub 2}S{sub 3} microrods of 6–10 μm long and 330–850 nm in diameter can be obtained by the microwave method with a careful selection of chemical and thermodynamic parameters of the synthesis. - Highlights: • Purity up to 90% of crystalline Sb{sub 2}S{sub 3} nanorods can be obtained by microwave heating. • The combination of solvent and sulfide type affects crystallinity & purity of Sb2S3. • The high pressure generated in microwave heating helps to form Sb{sub 2}S{sub 3} nanorods.

  16. Levels and risk factors of antimony contamination in human hair from an electronic waste recycling area, Guiyu, China.

    Science.gov (United States)

    Huang, Yue; Ni, Wenqing; Chen, Yaowen; Wang, Xiaoling; Zhang, Jingwen; Wu, Kusheng

    2015-05-01

    The primitive electronic waste (e-waste) recycling has brought a series of environmental pollutants in Guiyu, China. Antimony is one of the important metal contaminants and has aroused the global concerns recently. We aimed to investigate concentrations of antimony in human hair from Guiyu and compared them with those from a control area where no e-waste recycling exists, and assessed the potential risk factors. A total of 205 human hair samples from Guiyu and 80 samples from Jinping were collected for analysis. All volunteers were asked to complete a questionnaire including socio-demographic characteristics and other possible factors related to hair antimony exposure. The concentrations of hair antimony were analyzed using atomic absorption spectrophotometer. Our results indicated that the level of hair antimony in volunteers from Guiyu (median, 160.78; range, 6.99-4412.59 ng/g) was significantly higher than those from Jinping (median, 61.74; range, 2.98-628.43 ng/g). The residents who engaged in e-waste recycling activities in Guiyu had higher hair antimony concentrations than others (P waste recycling. Multiple stepwise regression analysis indicated that hair antimony concentrations were associated with education level (β = -0.064), the time of residence in Guiyu (β = 0.112), living house also served as e-waste workshop (β = 0.099), the work related to e-waste (β = 0.169), and smoking (β = 0.018). The elevated hair antimony concentrations implied that the residents in Guiyu might be at high risk of antimony contamination, especially the e-waste recycling workers. Work related to e-waste recycling activities and long-time residence in Guiyu contributed to the high hair antimony exposure.

  17. Double blind, randomized controlled trial, to evaluate the effectiveness of a controlled nitric oxide releasing patch versus meglumine antimoniate in the treatment of cutaneous leishmaniasis [NCT00317629

    Directory of Open Access Journals (Sweden)

    Silva Federico A

    2006-05-01

    Full Text Available Abstract Background Cutaneous Leishmaniasis is a worldwide disease, endemic in 88 countries, that has shown an increasing incidence over the last two decades. So far, pentavalent antimony compounds have been considered the treatment of choice, with a percentage of cure of about 85%. However, the high efficacy of these drugs is counteracted by their many disadvantages and adverse events. Previous studies have shown nitric oxide to be a potential alternative treatment when administered topically with no serious adverse events. However, due to the unstable nitric oxide release, the topical donors needed to be applied frequently, making the adherence to the treatment difficult. The electrospinning technique has allowed the production of a multilayer transdermal patch that produces a continuous and stable nitric oxide release. The main objective of this study is to evaluate this novel nitric oxide topical donor for the treatment of cutaneous leishmaniasis. Methods and design A double-blind, randomized, double-masked, placebo-controlled clinical trial, including 620 patients from endemic areas for Leishmaniasis in Colombia was designed to investigate whether this patch is as effective as meglumine antimoniate for the treatment of cutaneous leishmaniasis but with less adverse events. Subjects with ulcers characteristic of cutaneous leishmaniasis will be medically evaluated and laboratory tests and parasitological confirmation performed. After checking the inclusion/exclusion criteria, the patients will be randomly assigned to one of two groups. During 20 days Group 1 will receive simultaneously meglumine antimoniate and placebo of nitric oxide patches while Group 2 will receive placebo of meglumine antimoniate and active nitric oxide patches. During the treatment visits, the medications will be daily administered and the presence of adverse events assessed. During the follow-up, the research group will visit the patients at days 21, 45, 90 and 180. The

  18. Redox speciation analysis of antimony in soil extracts by hydride generation atomic fluorescence spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Fuentes, Edwar; Pinochet, Hugo; Gregori, Ida de E-mail: idegrego@ucv.cl; Potin-Gautier, Martine

    2003-07-18

    A sensitive atomic spectrometric method for the redox speciation analysis of antimony in soils is described. The method is based on the selective generation of stibine from Sb(III) in a continuous flow system using atomic fluorescence spectrometry for detection. Sb(V) is masked by citric or oxalic acid in HCl medium. The procedure was optimized with synthetic solutions of Sb(III) and Sb(V). The effect of carboxylic acid and HCl concentration on the recovery of Sb(III) and Sb(V) species from standard solutions, and on the fluorescence signal were studied. Both species were extracted from soil with H{sub 2}O, 0.05 mol l{sup -1} EDTA and 0.25 mol l{sup -1} H{sub 2}SO{sub 4}. Since the soil samples were collected from sites impacted by copper mining activities, the effect of Cu{sup 2+} on the determination of antimony in synthetic solutions and soil extracts was studied. Cu{sup 2+} decreased the Sb(III) signal, but had no effect on the total antimony determination. Therefore, the selective determination of Sb(III) was carried out in citric acid-HCl medium, using the analyte addition technique. Total antimony in soil extracts was determined using the standard calibration technique after reducing Sb(V) to Sb(III) at room temperature with KI-ascorbic acid. The Sb(V) concentration was calculated from the difference between total antimony and Sb(III). The limits of detection (PS Analytical, Excalibur Millennium model) were 17 and 10 ng l{sup -1} for Sb(III) and total antimony, respectively, and the R.S.D. at the 0.5-{mu}g l{sup -1} level were 2.5 and 2.4%, respectively. The total antimony concentration of soils is in the mg kg{sup -1} range; the Sb recovery from the different soils by the extracting solutions was between less than 0.02% and approximately 10%. Similar recoveries were obtained using EDTA and sulfuric acid solutions. Sb(V) was found to be the main antimony species extracted from soils.

  19. Co-doping with antimony to control phosphorous diffusion in germanium

    KAUST Repository

    Tahini, H. A.

    2013-02-15

    In germanium, phosphorous and antimony diffuse quickly and as such their transport must be controlled in order to design efficient n-typed doped regions. Here, density functional theory based calculations are used to predict the influence of double donor co-doping on the migration activation energies of vacancy-mediated diffusion processes. The migration energy barriers for phosphorous and antimony were found to be increased significantly when larger clusters involving two donor atoms and a vacancy were formed. These clusters are energetically stable and can lead to the formation of even larger clusters involving a number of donor atoms around a vacancy, thereby affecting the properties of devices.

  20. Reaction of Antimony-Uranium Composite Oxide in the Chlorination Treatment of Waste Catalyst - 13521

    International Nuclear Information System (INIS)

    Sawada, Kayo; Hirabayashi, Daisuke; Enokida, Youichi

    2013-01-01

    The effect of oxygen gas concentration on the chlorination treatment of antimony-uranium composite oxide catalyst waste was investigated by adding different concentrations of oxygen at 0-6 vol% to its chlorination agent of 0.6 or 6 vol% hydrogen chloride gas at 1173 K. The addition of oxygen tended to prevent the chlorination of antimony in the oxide. When 6 vol% hydrogen chloride gas was used, the addition of oxygen up to 0.1 vol% could convert the uranium contained in the catalyst to U 3 O 8 without any significant decrease in the reaction rate compared to that of the treatment without oxygen. (authors)

  1. Potent naphthoquinones against antimony-sensitive and -resistant Leishmania parasites: synthesis of novel α- and nor-α-lapachone-based 1,2,3-triazoles by copper-catalyzed azide-alkyne cycloaddition.

    Science.gov (United States)

    Guimarães, Tiago T; Pinto, Maria do Carmo F R; Lanza, Juliane S; Melo, Maria N; do Monte-Neto, Rubens L; de Melo, Isadora M M; Diogo, Emilay B T; Ferreira, Vitor F; Camara, Celso A; Valença, Wagner O; de Oliveira, Ronaldo N; Frézard, Frédéric; da Silva, Eufrânio N

    2013-05-01

    Continuing our screening program for novel anti-parasite compounds, we synthesized seven 1,4-naphthoquinones coupled to 1,2,3-triazoles, five nor-β-lapachone-based 1,2,3-triazoles and ten α-lapachone-based 1,2,3-triazoles. These and other naphthoquinonoid compounds were evaluated for their activity against promastigote forms of antimony-sensitive and -resistant strains of Leishmania infantum (syn. Leishmania chagasi) and Leishmania amazonensis. The toxicity of these compounds to mammalian cells was also examined. The substances were more potent than an antimonial drug, with IC50 values ranging from 1.0 to 50.7 μM. Nor-α-lapachone derivatives showed the highest antileishmanial activity, with selectivity indices in the range of 10-15. These compounds emerged as important leads for further investigation as antileishmanial agents. Additionally, one of these compounds exhibited cross-resistance in Sb-resistant Leishmania and could provide a molecular tool for investigating the multidrug resistance mechanisms in Leishmania parasites. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  2. Influence of cooling rate and antimony addition content on graphite morphology and mechanical properties of a ductile iron

    Directory of Open Access Journals (Sweden)

    Liu Zhe

    2012-05-01

    Full Text Available Cooling rate and inoculation practice can greatly affect the graphite morphology of ductile irons. In the present research, the effects of the cooling rate and antimony addition on the graphite morphology and mechanical properties of ductile irons have been studied. Three ductile iron castings were prepared through solidification under cooling conditions S (slow, M (medium and F (fast. The cooling rates around the equilibrium eutectic temperature (1,150 ℃ for these cooling conditions (S, M and F were set at 0.21 ℃·min-1, 0.32 ℃·min-1 and 0.37 ℃·min-1, respectively. In addition, four ductile iron castings were prepared by adding 0.01%, 0.02%, 0.03% and 0.04% (by weight antimony, respectively under the slow cooling condition. The results show that the nodularity index, tensile strength and hardness of the ductile iron castings without antimony addition are all improved with the increase of cooling rate, while the ductile iron casting solidified under the medium cooling rate possesses the largest number of graphite nodules. Furthermore, for the four antimony containing castings, the graphite morphology and tensile strength are also improved by the antimony additions, and the effect of antimony addition is intensified when the addition increases from 0.01% to 0.03%. Moreover, the rare earth elements (REE/antimony ratio of 2 appears to be the most effective for fine nodular graphite formation in ductile iron.

  3. Effects of spark plasma sintering conditions on the anisotropic thermoelectric properties of bismuth antimony telluride

    DEFF Research Database (Denmark)

    Han, Li; Hegelund Spangsdorf, Steeven; Van Nong, Ngo

    2016-01-01

    Bismuth antimony telluride (BixSb2-xTe3, 0.4 room-temperature thermoelectric power generation. In this work, p-type Bi0.4Sb1.6Te3 samples were prepared under various conditions (temperature, holding time, and ramp...

  4. Mixing of phosphorus and antimony ions in silicon by recoil implantation

    International Nuclear Information System (INIS)

    Kwok, H.L.; Lam, Y.W.; Wong, S.P.; Poon, M.C.

    1986-01-01

    The effects of mixing phosphorus and antimony ions in silicon by recoil implantation were examined. The electrical properties after ion mixing were investigated, and the results were compared with those obtained using other techniques. Different degrees of activation were also studied, by investigating the annealing behaviour. (U.K.)

  5. Improvement of hydrogen storage kinetics in ball-milled magnesium doped with antimony

    Czech Academy of Sciences Publication Activity Database

    Čermák, Jiří; Král, Lubomír; Roupcová, Pavla

    2017-01-01

    Roč. 42, č. 9 (2017), s. 6144-6151 ISSN 0360-3199 R&D Projects: GA MŠk(CZ) LQ1601 Institutional support: RVO:68081723 Keywords : Hydrogen * Hydrogen storage * Storage capacity * Magnesium alloys * Antimony Subject RIV: JJ - Other Materials OBOR OECD: Materials engineering Impact factor: 3.582, year: 2016

  6. Dismantling and chemical characterization of spent Peltier thermoelectric devices for antimony, bismuth and tellurium recovery.

    Science.gov (United States)

    Balva, Maxime; Legeai, Sophie; Garoux, Laetitia; Leclerc, Nathalie; Meux, Eric

    2017-04-01

    Major uses of thermoelectricity concern refrigeration purposes, using Peltier devices, mainly composed of antimony, bismuth and tellurium. Antimony was identified as a critical raw material by EU and resources of bismuth and tellurium are not inexhaustible, so it is necessary to imagine the recycling of thermoelectric devices. That for, a complete characterization is needed, which is the aim of this work. Peltier devices were manually dismantled in three parts: the thermoelectric legs, the alumina plates on which remain the electrical contacts and the silicone paste used to connect the plates. The characterization was performed using five Peltier devices. It includes mass balances of the components, X-ray diffraction analysis of the thermoelectric legs and elemental analysis of each part of the device. It appears that alumina represents 45% of a Peltier device in weight. The electrical contacts are mainly composed of copper and tin, and the thermoelectric legs of bismuth, tellurium and antimony. Thermoelectric legs appear to be Se-doped Bi 2 Te 3 and (Bi 0,5 Sb 1,5 )Te 3 for n type and p type semiconductors, respectively. This work shows that Peltier devices can be considered as a copper ore and that thermoelectric legs contain high amounts of bismuth, tellurium and antimony compared to their traditional resources.

  7. ANTIMONY HALIDES AND HgX2 (X = Cl, Br AMINE ADDUCTS: SYNTHESIS AND INFRARED STUDY

    Directory of Open Access Journals (Sweden)

    NDONGO GUEYE

    2013-12-01

    Full Text Available Eight new SbF3, SbCl5 and HgX2 (X = Cl, Br amine adducts have been synthesized and their infrared study carried out. Discrete structures have been suggested on the basis of elemental analysis and infrared data, the coordination number of antimony varying from five to nine, while the environment around Hg is tetrahedral.

  8. On the segregation behavior of tin and antimony at grain boundaries of polycrystalline bcc iron

    Czech Academy of Sciences Publication Activity Database

    Lejček, Pavel; Šandera, P.; Horníková, J.; Pokluda, J.; Godec, M.

    2016-01-01

    Roč. 363, Feb (2016), 140-144 ISSN 0169-4332 R&D Projects: GA ČR GAP108/12/0144 Institutional support: RVO:68378271 Keywords : grain boundary segregation * tin * antimony * Fe based alloy * AES quantification Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.387, year: 2016

  9. Morphology and photoresponse of crystalline antimony film grown on mica by physical vapor deposition

    Directory of Open Access Journals (Sweden)

    Shafa Muhammad

    2016-09-01

    Full Text Available Antimony is a promising material for the fabrication of photodetectors. This study deals with the growth of a photosensitive thin film by the physical vapor deposition (PVD of antimony onto mica surface in a furnace tube. The geometry of the grown structures was studied via scanning electron microscopy (SEM, X-ray diffraction (XRD, energy-dispersive X-ray spectroscopy (EDX and elemental diffraction analysis. XRD peaks of the antimony film grown on mica mostly matched with JCPDF Card. The formation of rhombohedral crystal structures in the film was further confirmed by SEM micrographs and chemical composition analysis. The Hall measurements revealed good electrical conductivity of the film with bulk carrier concentration of the order of 1022 Ω·cm-3 and mobility of 9.034 cm2/Vs. The grown film was successfully tested for radiation detection. The photoresponse of the film was evaluated using its current-voltage characteristics. These investigations revealed that the photosensitivity of the antimony film was 20 times higher than that of crystalline germanium.

  10. Reaction products and corrosion of molybdenum electrode in glass melt containing antimony oxides and sodium sulfate

    Czech Academy of Sciences Publication Activity Database

    Matěj, J.; Langrová, Anna

    2012-01-01

    Roč. 56, č. 3 (2012), s. 280-285 ISSN 0862-5468 Institutional support: RVO:67985831 Keywords : antimony oxides * corrosion * glass melt * Molybdenum electrode * sulfate Subject RIV: DD - Geochemistry Impact factor: 0.418, year: 2012 http://www.ceramics-silikaty.cz/2012/pdf/2012_03_280.pdf

  11. Differences in antimony and arsenic releases from lead smelter fly ash in soils

    Czech Academy of Sciences Publication Activity Database

    Ettler, V.; Mihaljevič, M.; Šebek, O.; Valigurova, R.; Klementová, Mariana

    2012-01-01

    Roč. 72, Supp. 4 (2012), s. 15-22 ISSN 0009-2819 Institutional research plan: CEZ:AV0Z40320502 Keywords : Antimony * Arsenic * Lead smelting * Fly ash * Soil * Mobility Subject RIV: CA - Inorganic Chemistry Impact factor: 1.351, year: 2012

  12. Diel variation of arsenic, molybdenum and antimony in a stream draining natural As geochemical anomaly

    Czech Academy of Sciences Publication Activity Database

    Drahota, P.; Nováková, B.; Matoušek, Tomáš; Mihaljevič, M.; Rohovec, Jan; Filippi, Michal

    2013-01-01

    Roč. 31, APR (2013), s. 84-93 ISSN 0883-2927 Institutional research plan: CEZ:AV0Z30130516 Institutional support: RVO:68081715 ; RVO:67985831 Keywords : arsenic * molybdenum * antimony * trace elements * diel cycle Subject RIV: CB - Analytical Chemistry, Separation; DD - Geochemistry (GLU-S) Impact factor: 2.021, year: 2013

  13. Antimony substitution in SmFeAsO

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Daniel; Braun, Hans F. [Universitaet Bayreuth (Germany)

    2015-07-01

    In the iron based compounds structural and magnetic phase transitions can be suppressed by applying external hydrostatic pressure and superconductivity emerges. Beside hydrostatic pressure, it is possible to apply chemical pressure by the substitution of atoms in the compounds with smaller ones. Such a substitution was successful for example in LaFeAs{sub 1-x}P{sub x}O, where the parent compound shows a structural and a spin-density-wave transition and the P doped samples become superconducting. We are interested in the opposite way and substitute the As by the bigger Sb. In literature, the substitution in the La-1111 compounds was possible up to a substitution level of 40 %. With Sm, instead of La, we used a smaller rare-earth metal. We present the results obtained on polycrystalline samples characterized by Xray powder diffraction and resistivity measurements.

  14. Investigation of physico-mechanical properties of flexible poly (vinyl chloride) filled with antimony trioxide using ionizing radiation.

    Science.gov (United States)

    Elnaggar, Mona Y; Fathy, E S; Hassan, Medhat M

    2018-04-12

    Composites of polyvinyl chloride (PVC) with 2% calcium carbonate, 2% diethyl phthalate, 2% paraffin wax and 2% lead sulphate and different contents of antimony trioxide (Sb 2 O 3 ) prepared by melting and irradiated with gamma ray have been considered. Assessment of the mechanical and thermal properties of the unirradiated and irradiated flexible polyvinyl chloride (FPVC) were completed utilizing elasticity (TS), Elongation at break (Eb) and thermogravimetric analysis measurements. TS and thermal stability of FPVC displayed advanced improvement after addition of additives and this approach highlighted the efficiency of those ingredients on PVC. The compounding of FPVC with Sb 2 O 3 in various extents was examined by FTIR, X-ray diffraction and scanning electron microscope methods. It is obvious that the presence of Sb 2 O 3 begins impacting oxidative degradation, leading to a decrease in mechanical properties up to 10%. Moreover, a slight increase in the thermal stability of composites by exposure to ionizing radiation is apparently due to cross-linking of FPVC chains.

  15. Gamow–Teller resonances in the {sup 118}Sb compound nucleus: Puzzles of an experiment in Sarov

    Energy Technology Data Exchange (ETDEWEB)

    Urin, M. H., E-mail: urin@theor.mephi.ru [National Research Nuclear University MEPhI (Russian Federation)

    2016-03-15

    Contradictory data on the observation of Gamow–Teller resonances in the {sup 118}Sb compound nucleus are discussed along with the available interpretation of these data and planned experimental and theoretical investigations into Gamow–Teller resonances in a number of antimony isotopes.

  16. Carbon paste electrodes modified with a reaction product obtained by hydrolysis of an antimony(III) salt

    OpenAIRE

    Švancara, Ivan; Florescu, Monica; Stočes, Matěj; Baldrianová, Lucie; Svobodová, Eva; Badea, Mihaela

    2010-01-01

    In this article, a new type of antimony-modified electrode is described based on carbon-paste bulk dispersion of a precipitate obtained by hydrolysis of the respective Sb(III) salt. Subsequently, the resultant electrode (SbOL-CPE in two variants)  operated via the antimony film formed in nascenti at the electrode surface  was subjected to the basic characterisation with respect to its electroanalytical performance in the anodic stripping voltammetry of six heavy metal ions (Z...

  17. On the Effect of Antimony Segregation to the Electronic Properties of InAs/InAsSb Superlattices (Preprint)

    Science.gov (United States)

    2017-01-03

    distribution at the hetero-interfaces engendered by Sb segregation. * Electronic mail: heather.haugan.ctr@us.af.mil 2 I. INTRODUCTION Reuse After...AFRL-RX-WP-JA-2017-0231 ON THE EFFECT OF ANTIMONY SEGREGATION TO THE ELECTRONIC PROPERTIES OF INAS/INASSB SUPERLATTICES (PREPRINT...December 2016 Interim 11 September 2013 – 12 November 2016 4. TITLE AND SUBTITLE ON THE EFFECT OF ANTIMONY SEGREGATION TO THE ELECTRONIC

  18. Molecular Preadaptation to Antimony Resistance in Leishmania donovani on the Indian Subcontinent.

    Science.gov (United States)

    Dumetz, F; Cuypers, B; Imamura, H; Zander, D; D'Haenens, E; Maes, I; Domagalska, M A; Clos, J; Dujardin, J-C; De Muylder, G

    2018-04-25

    Antimonials (Sb) were used for decades for chemotherapy of visceral leishmaniasis (VL). Now abandoned in the Indian subcontinent (ISC) because of Leishmania donovani resistance, this drug offers a unique model for understanding drug resistance dynamics. In a previous phylogenomic study, we found two distinct populations of L. donovani : the core group (CG) in the Gangetic plains and ISC1 in the Nepalese highlands. Sb resistance was only encountered within the CG, and a series of potential markers were identified. Here, we analyzed the development of resistance to trivalent antimonials (Sb III ) upon experimental selection in ISC1 and CG strains. We observed that (i) baseline Sb III susceptibility of parasites was higher in ISC1 than in the CG, (ii) time to Sb III resistance was higher for ISC1 parasites than for CG strains, and (iii) untargeted genomic and metabolomic analyses revealed molecular changes along the selection process: these were more numerous in ISC1 than in the CG. Altogether these observations led to the hypothesis that CG parasites are preadapted to Sb III resistance. This hypothesis was experimentally confirmed by showing that only wild-type CG strains could survive a direct exposure to the maximal concentration of Sb III The main driver of this preadaptation was shown to be MRPA , a gene involved in Sb III sequestration and amplified in an intrachromosomal amplicon in all CG strains characterized so far. This amplicon emerged around 1850 in the CG, well before the implementation of antimonials for VL chemotherapy, and we discuss here several hypotheses of selective pressure that could have accompanied its emergence. IMPORTANCE The "antibiotic resistance crisis" is a major challenge for scientists and medical professionals. This steady rise in drug-resistant pathogens also extends to parasitic diseases, with antimony being the first anti- Leishmania drug that fell in the Indian subcontinent (ISC). Leishmaniasis is a major but neglected infectious

  19. Selective speciation of inorganic antimony on tetraethylenepentamine bonded silica gel column and its determination by graphite furnace atomic absorption spectrometry.

    Science.gov (United States)

    Mendil, Durali; Bardak, Hilmi; Tuzen, Mustafa; Soylak, Mustafa

    2013-03-30

    A speciation system for antimony (III) and antimony (V) ions that based on solid phase extraction on tetraethylenepentamine bonded silica gel has been established. Antimony was determined by graphite furnace atomic absorption spectrometry (GF-AAS). Analytical conditions including pH, sample volume, etc., were studied for the quantitative recoveries of Sb (III) and Sb (V). Matrix effects on the recovery were also investigated. The recovery values and detection limit for antimony (III) at optimal conditions were found as >95% and 0.020 μg L(-1), respectively. Preconcentration factor was calculated as 50. The capacity of adsorption for the tetraethylenepentamine bonded silica gel was 7.9 mg g(-1). The validation was checked by analysis of NIST SRM 1573a Tomato laves and GBW 07605 Tea certified reference materials. The procedure was successfully applied to speciation of antimony in tap water, mineral water and spring water samples. Total antimony was determined in refined salt, unrefined salt, black tea, rice, tuna fish and soil samples after microwave digestion and presented enrichment method combination. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Treatment of antimony mine drainage: challenges and opportunities with special emphasis on mineral adsorption and sulfate reducing bacteria.

    Science.gov (United States)

    Li, Yongchao; Hu, Xiaoxian; Ren, Bozhi

    2016-01-01

    The present article summarizes antimony mine distribution, antimony mine drainage generation and environmental impacts, and critically analyses the remediation approach with special emphasis on iron oxidizing bacteria and sulfate reducing bacteria. Most recent research focuses on readily available low-cost adsorbents, such as minerals, wastes, and biosorbents. It is found that iron oxides prepared by chemical methods present superior adsorption ability for Sb(III) and Sb(V). However, this process is more costly and iron oxide activity can be inhibited by plenty of sulfate in antimony mine drainage. In the presence of sulfate reducing bacteria, sulfate can be reduced to sulfide and form Sb(2)S(3) precipitates. However, dissolved oxygen and lack of nutrient source in antimony mine drainage inhibit sulfate reducing bacteria activity. Biogenetic iron oxide minerals from iron corrosion by iron-oxidizing bacteria may prove promising for antimony adsorption, while the micro-environment generated from iron corrosion by iron oxidizing bacteria may provide better growth conditions for symbiotic sulfate reducing bacteria. Finally, based on biogenetic iron oxide adsorption and sulfate reducing bacteria followed by precipitation, the paper suggests an alternative treatment for antimony mine drainage that deserves exploration.

  1. Syntheses and characterization of one-dimensional alkali metal antimony(III) thiostannates(IV), A{sub 2}Sb{sub 2}Sn{sub 3}S{sub 10} (A=K, Rb, Cs)

    Energy Technology Data Exchange (ETDEWEB)

    Yohannan, Jinu P.; Vidyasagar, Kanamaluru, E-mail: kvsagar@iitm.ac.in

    2015-01-15

    Three new isostructural quaternary antimony(III) thiostannates(IV), A{sub 2}Sb{sub 2}Sn{sub 3}S{sub 10} (A=K, Rb, Cs) have been synthesized by using alkali metal thiosulfate flux and structurally characterized by X-ray diffraction. Their structures contain A{sup +} ions around the [Sb{sub 2}Sn{sub 3}S{sub 10}]{sup 2−} chains, which are built from SbS{sub 3} pyramids, SnS{sub 6} octahedra and SnS{sub 4} tetrahedra. Raman and Mössbauer spectroscopic measurements corroborate the oxidation states and coordination environments of Sb(III) and Sn(IV). All three compounds are wide band gap semiconductors. Potassium compound undergoes partial exchange with strontium, cadmium and lead ions. - Graphical abstract: Syntheses, crystal structure, spectroscopic and partial ion-exchange studies of new one-dimensional alkali metal antimony(III) thiostannates(IV), A{sub 2}Sb{sub 2}Sn{sub 3}S{sub 10} (A=K, Rb, Cs) are described. - Highlights: • Syntheses of new alkali metal antimony(III) thiostannates(IV), A{sub 2}Sb{sub 2}Sn{sub 3}S{sub 10} (A=K, Rb, Cs). • Wide band gap semiconductors with one-dimensional structure. • Topotactic partial exchange of K{sup +} ions of K{sub 2}Sb{sub 2}Sn{sub 3}S{sub 10} with Sr{sup 2+}, Cd{sup 2+} and Pb{sup 2+} ions.

  2. Antimony Influence on Shape of Eutectic Silicium in Al-Si Based Alloys

    Directory of Open Access Journals (Sweden)

    Bolibruchová D.

    2017-12-01

    Full Text Available Liquid AI-Si alloys are usually given special treatments before they are cast to obtain finer or modified matrix and eutectic structures, leading to improved properties. For many years, sodium additions to hypoeutectic and eutectic AI-Si melts have been recognized as the most effective method of modifying the eutectic morphology, although most of the group IA or IIA elements have significant effects on the eutectic structure. Unfortunately, many of these approaches also have associated several founding difficulties, such as fading, forming dross in presence of certain alloying elements, reduced fluidity, etc. ln recent years, antimony additions to AI-Si castings have attracted considerable attention as an alternative method of refining the eutectic structure. Such additions eliminate many of the difficulties listed above and provide permanent (i.e. non-fading refining ability. In this paper, the authors summarize work on antimony treatment of Al-Si based alloys.

  3. A facile and fast route to prepare antimony (Sb) nanostructures without additives

    KAUST Repository

    Shah, M.A.

    2011-12-01

    Herein, we report a safe, low cost and reproducible approach for the synthesis of antimony (Sb) nanostructures with most of them having prism like morphology and having well defined faces in the range of ∼70210 nm. The organics free approach is based on a reaction of antimony powder and pure water at ∼210 °C without using any harmful additives and amines. The XRD pattern confirmed the composition and crystallinity of the grown nanostructures. The reported method besides being organics free is economical, fast and free of pollution, which will make it suitable for large scale production. Furthermore, it is well expected that such a technique could be extended to prepare many other important metal and metal oxide nanostructures. The prospects of the process are bright and promising. © 2012 Sharif University of Technology. Production and hosting by Elsevier B.V. All rights reserved.

  4. Evaluation of the efficiency of the processes of purification of antimony to semiconductor grade purity

    International Nuclear Information System (INIS)

    Walis, L.; Rowinska, L.; Panczyk, E.

    1992-01-01

    A complex of techniques for purification of antimony from arsenic has been examined with the aid of radiotracer 76 As. The investigated processes comprised vacuum distillation, zone melting and remelting of the metal under artificial slags. The purification efficiencies for the above processes were high and amounted to 94% (for 30% of the charge), 50% (for 50% of the charge) and 99.5% (for 60% of the charge), respectively. Attempts were made to determine the kinetics of the separation of arsenic from antimony by distillation. The application of the radioactive tracer made it possible to determine rapidly the distribution of impurities after each stage of the process within a wide concentration range (10 -2 -10 -7 g/g). (author). 7 refs, 4 figs, 6 tabs

  5. Determination by neutron activation analysis of loss of arsenic, antimony, bromine and mercury during lyophilization

    International Nuclear Information System (INIS)

    Carlson, M.; Litman, R.

    1978-01-01

    Neutron activation analysis has been used to monitor the loss of arsenic, as dimethylarsinic acid, (CH 3 ) 2 AsOOH, or as sodium arsenate (Na 2 HAsO 4 .7H 2 O), antimony (as potassium antimony, tartrate, KSbC 4 O 7 .1/2H 2 O) and bromine (as bromide ion) during lyophilization of acidified and neutral aqueous synthetic and environmental samples. Losses of Sb and As ranged from zero to 60%, while losses of bromine were constant (at 91%) in acidic solutions. The variable losses of As and Sb were due solely to the presence of and partial decomposition of the (CH 3 ) 2 AsOOH. Electrochemical oxidation of Br - to Br 2 is responsible for the high losses of bromine. In addition losses of mercury (as methylmercuric chloride) were 1O0% in both acidic and neutral aqueous synthetic samples during lyophilization. (author)

  6. Reaction of Antimony-Uranium Composite Oxide in the Chlorination Treatment of Waste Catalyst - 13521

    Energy Technology Data Exchange (ETDEWEB)

    Sawada, Kayo [EcoTopia Science Institute (Japan); Hirabayashi, Daisuke; Enokida, Youichi [Department of Materials, Physics and Energy Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603 (Japan)

    2013-07-01

    The effect of oxygen gas concentration on the chlorination treatment of antimony-uranium composite oxide catalyst waste was investigated by adding different concentrations of oxygen at 0-6 vol% to its chlorination agent of 0.6 or 6 vol% hydrogen chloride gas at 1173 K. The addition of oxygen tended to prevent the chlorination of antimony in the oxide. When 6 vol% hydrogen chloride gas was used, the addition of oxygen up to 0.1 vol% could convert the uranium contained in the catalyst to U{sub 3}O{sub 8} without any significant decrease in the reaction rate compared to that of the treatment without oxygen. (authors)

  7. Preconcentration and Determination of Antimony in Drinking Water Bottled by Modified Nano-Alumina

    Directory of Open Access Journals (Sweden)

    M Mohammad Zakizade

    2016-01-01

    Full Text Available Abstract Introduction: Antimony trioxide (Sb2O3 has been utilized as a catalyst in polyethylene terephtalate (PET production, and the studies conducted on the bottled water has demonstrated that antimony can be leached from PET bottles into drinking water. Methods: In this study, a simple method was applied in order to determine the trace amount of antimony in bottled drinking water based on preconcentration /solid phase extraction. The nano alumina modified with Schiff base ligand was used in regard with Sb preconcentration. The experiments were performed in a continuous system and HCI was used as eluent of Sb ion. Several chemical and flow variables were optimized for a quantitative preconcentration and determination of Sb ion. The atomic absorption spectroscopy was used to determine Sb ion concentration. In order to study the keeping conditions on the leaching of Sb ion from PET plastic, drinking water bottles were kept in different conditions(room temperature, sunny light and -18˚C. Results: The calibration graph was linear in the range of 0.5 to 15.0 ppm Sb with detection limit of 0.055 ppm. The flow rate of sample was optimized in range of 1.0-9.0 mLmin-1 and Sb ion can be quantitatively eluted at 90 Vsample: Veluent retio. Conclusion: The study results revealed that the modified nano alumina is an effective sorbent in regard with absorbing Sb ion from water and HCI 1M can be used as an appropriate eluent. Maximum leaching of Sb ion is observed when the bottled drinking water was exposed to the sun light. Keywords: Antimony; Bottled drinking water; Modified alumina; Preconcentration

  8. Purification of indium, gallium, and antimony by melting with synthetic slug

    International Nuclear Information System (INIS)

    Walis, L.; Rowinska, L.; Nowicki, A.

    1997-01-01

    The tracer technique has been used for metal purification process control. The indium, gallium and antimony have been purified up to semiconductor purity in the melting with synthetic slug process. The 115m Cd, 59 Fe, 204 Tl. 76 As, 210 Bi have been used as tracers. The high effectiveness of proposed purification method have been found in the cases of indium and gallium. 6 refs, 2 figs, 2 tabs

  9. Optical switching property of a light-induced pinhole in antimony thin film

    Science.gov (United States)

    Fukaya, Toshio; Tominaga, Junji; Nakano, Takashi; Atoda, Nobufumi

    1999-11-01

    Optical near-field recording, called a super-resolution near-field structure, records and retrieves small marks beyond the diffraction limit. A thin layer of an antimony (Sb) film, added to the usual phase-change optical disk, is the key material of this technique. Nonlinear optical properties of an Sb film, especially optical switching, were studied in the stationary state using a nanosecond pulse laser. Clear switching was observed under microscopic measurement.

  10. A NOVEL METHOD OF THE HYDRIDE SEPARATION FOR THE DETERMINATION OF ARSENIC AND ANTIMONY BY AAS

    Directory of Open Access Journals (Sweden)

    Ganden Supriyanto

    2010-06-01

    Full Text Available A novel method is proposed for the hydride separation when determinining of arsenic and antimony by AAS. A chromatomembrane cell was used as preconcentration-, extraction- and separation-manifold instead of the U-tube phase separator, which is normally fitted in continuous flow vapour systems generating conventionaly the hydrides. The absorbances of the hydrides produced were measured by an atomic absorption spectrophotometer at 193.7 nm and 217.6 nm. Under optimized analytical conditions, the calibration plot for arsenic was linear from 50 to 500 ng.mL-1 (r2 = 0.9982. The precision for three subsequent measurements of 500 ng.mL-1 arsenic gave rise to a relative standard deviation of 0.4%. The detection limit was 15 ng.mL-1, which is much lower compared with that of the conventional hydride system (2000 ng.mL-1. A similar result was observed in case of antimony: the detection limit was 8 ng.mL-1 when the proposed method was applied. Consequently, the sensitivity of the novel method surpasses systems with conventional hydride generation, i.e. the precision and the acuracy increase whereas the standard deviation and the detection limit decrease. The proposed method was applied in pharmacheutial analysis and the certified As-content of a commercial product was very sufficiently confirmed.   Keywords: Chromatomembrane Cell, Hydride separation, Arsenic detection, Antimony detection, AAS

  11. Antimony sulfide thin films prepared by laser assisted chemical bath deposition

    Energy Technology Data Exchange (ETDEWEB)

    Shaji, S., E-mail: sshajis@yahoo.com [Facultad de Ingeniería Mecánica y Eléctrica, Universidad Autónoma de Nuevo León, Av. Pedro de Alba s/n, Ciudad Universitaria, San Nicolás de los Garza, Nuevo León, 66455 (Mexico); CIIDIT—Universidad Autónoma de Nuevo León, Apodaca, Nuevo León (Mexico); Garcia, L.V. [Facultad de Ingeniería Mecánica y Eléctrica, Universidad Autónoma de Nuevo León, Av. Pedro de Alba s/n, Ciudad Universitaria, San Nicolás de los Garza, Nuevo León, 66455 (Mexico); Loredo, S.L. [Centro de Investigación en Materiales Avanzados (CIMAV), Unidad Monterrey, PIIT, Apodaca, Nuevo León (Mexico); Krishnan, B. [Facultad de Ingeniería Mecánica y Eléctrica, Universidad Autónoma de Nuevo León, Av. Pedro de Alba s/n, Ciudad Universitaria, San Nicolás de los Garza, Nuevo León, 66455 (Mexico); CIIDIT—Universidad Autónoma de Nuevo León, Apodaca, Nuevo León (Mexico); and others

    2017-01-30

    Highlights: • Antimony sulfide thin films were prepared by normal CBD and laser assisted CBD. • Characterized these films using XRD, XPS, AFM, optical and electrical measurements. • Accelerated growth was observed in the laser assisted CBD process. • These films were photoconductive. - Abstract: Antimony sulfide (Sb{sub 2}S{sub 3}) thin films were prepared by laser assisted chemical bath deposition (LACBD) technique. These thin films were deposited on glass substrates from a chemical bath containing antimony chloride, acetone and sodium thiosulfate under various conditions of normal chemical bath deposition (CBD) as well as in-situ irradiation of the chemical bath using a continuous laser of 532 nm wavelength. Structure, composition, morphology, optical and electrical properties of the Sb{sub 2}S{sub 3} thin films produced by normal CBD and LACBD were analyzed by X-Ray diffraction (XRD), Raman Spectroscopy, Atomic force microscopy (AFM), X-Ray photoelectron spectroscopy (XPS), UV–vis spectroscopy and Photoconductivity. The results showed that LACBD is an effective synthesis technique to obtain Sb{sub 2}S{sub 3} thin films for optoelectronic applications.

  12. Increased parasite surface antigen-2 expression in clinical isolates of Leishmania donovani augments antimony resistance.

    Science.gov (United States)

    Bhandari, Vasundhra; Kumar, Dhiraj; Verma, Sandeep; Srividya, Gurumurthy; Negi, Narendra Singh; Singh, Ruchi; Salotra, Poonam

    2013-11-01

    Resistance to sodium antimony gluconate (SAG) is a major cause of therapeutic failure in a large proportion of visceral leishmaniasis (VL) cases. Determinants of SAG resistance have been widely studied; however, the mechanism operating in clinical isolates is poorly understood. In the present study, expression of parasite surface antigen-2 (PSA-2) gene was studied in clinical isolates of Leishmania donovani comprising of antimony resistant (n=10) and sensitive (n=4) parasites. The expression of PSA-2 gene was found to be consistently high in SAG resistant clinical isolates (≥1.5-fold) at both transcript and protein level. Further, over-expression of PSA-2 in L. donovani isolates (LdPSA-2(++)) resulted in conversion of SAG sensitive phenotype to resistant. The LdPSA-2(++) parasites showed significantly decreased susceptibility towards SAG (>12-fold), amphotericin B (>4-fold) and miltefosine (>2.5-fold). Marked decrease in antimony accumulation and enhanced tolerance towards complement mediated lysis was evident in LdPSA-2(++) parasites. The study established the role of PSA-2 gene in SAG resistance and its potential as a biomarker to distinguish resistant and sensitive clinical isolates of L. donovani. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Parto prematuro após uso de antimonial pentavalente: relato de um caso Premature birth after the use of pentavalent antimonial: case report

    Directory of Open Access Journals (Sweden)

    Bruna Pinheiro Silveira

    2003-07-01

    Full Text Available Relata-se o caso de uma mulher de 19 anos, na 24ª semana de gravidez e com leishmaniose visceral. Tratada com antimonial pentavalente na posologia de 850mg/dia por 20 dias, ocorreu parto prematuro no quinto dia de tratamento e óbito da criança um dia após nascimento. Considerando a importância da protozoose no nosso meio e a raridade da associação com a gestação, julgamos de interesse a publicação do caso.A case is reported of a 19-year-old woman, at week 24 of gestation, with visceral leishmaniosis. She was treated with meglumine antimoniate at a dose of 850mg/day for 20 days. There occurred premature birth on day five of treatment and the neonate died one day after birth. Considering the importance of protozoiasis in our population and the rarity of the association with pregnancy, we resolved to publish the case.

  14. Structural and magnetic properties of nickel antimony ferrospinels

    International Nuclear Information System (INIS)

    Ivanov, S.A.; Tellgren, R.; Porcher, F.; André, G.; Ericsson, T.; Nordblad, P.; Sadovskaya, N.; Kaleva, G.; Politova, E.; Baldini, M.; Sun, C.; Arvanitis, D.; Anil Kumar, P.; Mathieu, R.

    2015-01-01

    Spinel-type compounds of Fe–Ni–Sb–O system were synthesized as polycrystalline powders. The crystal and magnetic properties were investigated using X-ray and neutron powder diffraction, Mössbauer and X-ray absorption spectroscopy and magnetization measurements. The samples crystallize in the cubic system, space group Fd – 3 m. The distribution of cations between octahedral and tetrahedral sites was refined from the diffraction data sets using constraints imposed by the magnetic, Mössbauer and EDS results and the ionic radii. The cation distribution and the temperature dependence of the lattice parameter (a) and the oxygen positional parameter (u) were obtained. A chemical formula close to Fe 0.8 Ni 1.8 Sb 0.4 O 4 was determined, with Sb 5+ cations occupying octahedral sites, and Fe 3+ and Ni 2+ occupying both tetrahedral and octahedral sites. Fe 3+ mainly (85/15 ratio) occupy tetrahedral sites, and conversely Ni 2+ mainly reside on octahedral ones. The magnetic unit cell is the same as the crystallographic one, having identical symmetry relations. The results indicate that the compounds have a collinear ferrimagnetic structure with antiferromagnetic coupling between the tetrahedral (A) and octahedral (B) sites. Uniquely, the temperature dependence of the net magnetization of this rare earth free ferrimagnet exhibits a compensation point. - Highlights: • Polycrystalline spinel-type compounds of (Fe,Ni)[Fe,Ni,Sb]2O4 were synthesized. • Fe (3+) and Ni (2+) cations occupy mainly tetrahedral (resp. octahedral) sites. • The ferrimagnetic behavior observed below 650 K is investigated in detail. • Squid magnetometry and neutron powder diffraction data are compared

  15. German standard methods for the examination of water, waste water and sludge: Anions (group D), determination of phosphorus compounds (D 11)

    International Nuclear Information System (INIS)

    1982-01-01

    The following method for the determination of phosphorus compounds in water and waste water is proposed. In acid solutions phosphate ions form with molybdate and antimony ions an antimonylphosphorusmolybdate-complex which is reduced to phosphorusmolybdenumblue by ascorbic acid. The intensity of the colour is determined by photometric methods. Polyphosphates and some organic phosphorus compounds are hydrolysed to orthophosphate by cooking in strong acid solutions. Other stable phosphorus compounds are decomposed by strong oxidizing agents (potassiumperoxidisulfate or nitric acid). (VG) [de

  16. Increased biliary excretion of glutathione is generated by the glutathione-dependent hepatobiliary transport of antimony and bismuth.

    Science.gov (United States)

    Gyurasics, A; Koszorús, L; Varga, F; Gregus, Z

    1992-10-06

    We have recently demonstrated that the hepatobiliary transport of arsenic is glutathione-dependent and is associated with a profound increase in biliary excretion of glutathione (GSH), hepatic GSH depletion and diminished GSH conjugation (Gyurasics A, Varga F and Gregus Z, Biochem Pharmacol 41: 937-944 and Gyurasics A, Varga F and Gregus Z, Biochem Pharmacol 42: 465-468, 1991). The present studies in rats aimed to determine whether antimony and bismuth, other metalloids in group Va of the periodic table, also possess similar properties. Antimony potassium tartrate (25-100 mumol/kg, i.v.) and bismuth ammonium citrate (50-200 mumol/kg, i.v.) increased up to 50- and 4-fold, respectively, the biliary excretion of non-protein thiols (NPSH). This resulted mainly from increased hepatobiliary transport of GSH as suggested by a close parallelism in the biliary excretion of NPSH and GSH after antimony or bismuth administration. Within 2 hr, rats excreted into bile 55 and 3% of the dose of antimony (50 mumol/kg, i.v.) and bismuth (150 mumol/kg, i.v.), respectively. The time courses of the biliary excretion of these metalloids and NPSH or GSH were strikingly similar suggesting co-ordinate hepatobiliary transport of the metalloids and GSH. However, at the peak of their excretion, each molecule of antimony or bismuth resulted in a co-transport of approximately three molecules of GSH. Diethyl maleate, indocyanine green and sulfobromophthalein (BSP), which decreased biliary excretion of GSH, significantly diminished excretion of antimony and bismuth into bile indicating that hepatobiliary transport of these metalloids is GSH-dependent. Administration of antimony, but not bismuth, decreased hepatic GSH level by 30% and reduced the GSH conjugation and biliary excretion of BSP. These studies demonstrate that the hepatobiliary transport of trivalent antimony and bismuth is GSH-dependent similarly to the hepatobiliary transport of trivalent arsenic. Proportionally to their biliary

  17. Development of an analytical method for antimony speciation in vegetables by HPLC-hydride generation-atomic fluorescence spectrometry.

    Science.gov (United States)

    Olivares, David; Bravo, Manuel; Feldmann, Jorg; Raab, Andrea; Neaman, Alexander; Quiroz, Waldo

    2012-01-01

    A new method for antimony speciation in terrestrial edible vegetables (spinach, onions, and carrots) was developed using HPLC with hydride generation-atomic fluorescence spectrometry. Mechanical agitation and ultrasound were tested as extraction techniques. Different extraction reagents were evaluated and optimal conditions were determined using experimental design methodology, where EDTA (10 mmol/L, pH 2.5) was selected because this chelate solution produced the highest extraction yield and exhibited the best compatibility with the mobile phase. The results demonstrated that EDTA prevents oxidation of Sb(III) to Sb(V) and maintains the stability of antimony species during the entire analytical process. The LOD and precision (RSD values obtained) for Sb(V), Sb(III), and trimethyl Sb(V) were 0.08, 0.07, and 0.9 microg/L and 5.0, 5.2, and 4.7%, respectively, for a 100 microL sample volume. The application of this method to real samples allowed extraction of 50% of total antimony content from spinach, while antimony extracted from carrots and onion samples ranged between 50 and 60 and 54 and 70%, respectively. Only Sb(V) was detected in three roots (onion and spinach) that represented 60-70% of the total antimony in the extracts.

  18. Highly active and stable Pt electrocatalysts promoted by antimony-doped SnO2 supports for oxygen reduction reactions

    DEFF Research Database (Denmark)

    Yin, Min; Xu, Junyuan; Li, Qingfeng

    2014-01-01

    Alternative composite supports for platinum catalysts were synthesized from antimony doped tin dioxide (ATO) nanoparticles. In the range of the antimony content from 0 to 11mol%, the highest electrical conductivity of 1.1Scm-1 at 130°C was obtained for the 5mol% Sb ATO, from which composite suppo...

  19. Leishmaniose cutânea com desfecho fatal durante tratamento com antimonial pentavalente American cutaneous leishmaniasis with fatal outcome during pentavalent antimoniate treatment

    Directory of Open Access Journals (Sweden)

    Meiri Vanderlei Nogueira de Lima

    2007-06-01

    Full Text Available Os autores relatam o caso de paciente de 58 anos, hipertensa e diabética, com diagnóstico de leishmaniose tegumentar americana, tratada com antimoniato de N-metil-glucamina (15mg SbV/kg/dia, acompanhada pelo serviço de atenção básica em saúde e que evoluiu para óbito no 18º dia de tratamento.The authors report a case of a 58 years-old, hypertensive, diabetic female patient, with the diagnosis of American cutaneous leishmaniasis, undergoing treatment with Nmethyl glucamine antimoniate (15mg SbV/Kg/day. She was followed up by the basic health care service, but has died on the 18th treatment day.

  20. Selective liquid-liquid extraction of antimony(III from hydrochloric acid media by N-n-octylaniline in xylene

    Directory of Open Access Journals (Sweden)

    M. A. ANUSE

    2004-04-01

    Full Text Available N-n-Octylaniline in xylene was used for the extraction separation of antimony(III from hydrochloric acid media. Antimony(III was extracted quantitatively with 10 mL 4 % N-n-octylaniline in xylene. It was stripped from the organic phase with 0.5 M ammonia and estimated photometrically by the iodide method. The effect of metal ion, acid, reagent concentration and various foreign ions was investigated. The method affords binary and ternary separation of antimony(III from tellurium(IV, selenium(IV, lead(II, bismuth(III, tin(IV, germanium(IV, copper(II, gold(III, iron(III and zinc(II. The method is applicable for the analysis of synthetic mixtures, alloys and semiconductor thin films. It is fast, accurate and precise.

  1. A thermodynamic investigation of liquid gold-antimony alloys

    International Nuclear Information System (INIS)

    Hayer, E.; Castanet, R.

    1995-01-01

    The enthalpies of mixing of liquid Au-Sb alloys were determined between 906 and 1028 K giving Δ mix H o m = x Sb x Au (-11.234-1.1078x Sb + 5.713x Sb 2 ) kJ mol -1 . The minimum was found at x Sb = 0.45 with Δ mix H o m = -2.62 ± 0.2 kJ mol -1 contrary to published measurements on liquid Au-Sb alloys. The limiting partial molar enthalpy of Au in Sb at 935 K was measured to Δ mix h o m (Au, liq, in ∞Sb, liq) = -6.05 ± 0.4 kJ mol -1 . The enthalpy of formation of the solid compound AuSb 2 determined at 298 K by solution calorimetry in liquid Sb, Δ f H o m (AuSb 2 ) = -5.40 ± 0.6 kJ mol -1 , is found in fair agreement with literature data. DTA measurements were performed on the Au-rich part of the liquidus and a new liquidus curve is suggested between Au and the eutectic concentration. The eutectic point was found at 630.37 ± 0.25 K and x Sb 0.350. (orig.)

  2. Leachability of antimony from energy ashes. Total contents, leachability and remedial suggestions; Lakning av antimon fraan energiaskor. Totalhalter, lakbarhet samt foerslag till aatgaerder

    Energy Technology Data Exchange (ETDEWEB)

    Baeckstroem, Mattias [Oerebro Univ. (Sweden)

    2006-01-15

    In the current project total concentrations for antimony in 31 energy ashes have been compiled. The average concentration of antimony in boiler fly ash and grate boiler fly ash is 192 and 1,140 mg/kg, respectively. The corresponding antimony concentrations for boiler ashes and grate bottom ashes are 86,5 and 61,8 mg/kg, respectively. Multivariate calculations clearly pointed out waste as the major source for antimony in ashes. The difference between total antimony concentration in fly ash and bottom ash is greatest for grate boilers, in average 18 times higher in the fly ash. The difference for CFB/BFB-boilers is only slightly more than 2. However, based on amount, 75% of the total antimony inventory is recovered in the fly ashes for both CFB/BFB and grate boilers. Eleven (eight of which were bottom ashes) out of the 31 samples exceeded the guidelines for inert waste. It is clear that the higher ionic strength in the solutions from the fly ashes contribute to decrease the solubility for critical minerals retaining antimony. In addition, the fly ashes have considerably larger effective surface able to sorb trace elements. A clear and positive covariance was discovered between aluminium and antimony. Furthermore, it was noted that antimony showed no typical anionic behaviour despite the fact that it according to the geochemical calculations should be present as SbO{sub 3}{sup -}. At L/S 10, a maximum of 1% of the total antimony concentration is leached. This should be compared to chloride that had 94% of the total concentration leached at L/S 10. There was no correlation between the leached antimony concentrations and the total antimony concentrations. The sequential extractions also suggest a low leachability for antimony from the ashes. In average only 9,6% is released at pH 7, 7,3% at pH 5, 3,6% during reducing conditions and 3,2% during oxidising conditions. In total, only 24% of the total antimony concentrations is released during the four extraction steps. The

  3. Dual mode antimony electrode for simultaneous measurements of PO2 and pH.

    Science.gov (United States)

    Sjöberg, F; Nilsson, G

    2000-01-01

    In biomedical research and clinical medicine there is a demand for potent sensors to measure the components that make up blood gas analyses. Today, as when the electrochemical PO2, PCO2 and pH electrodes were first introduced, these measurements are usually made with the same type of sensor technology. The aims of the present study were, firstly, to find out whether the platinum cathode in the Clark electrode can be replaced by antimony for oxygen measurements (amperometry (A)); secondly, whether, during oxygen measurements, the inherent corrosion potential of the antimony metal can be used for measurement of pH in the same measurement area (potentiometry (P)). An electrode of purified, crystallographically orientated monocrystalline antimony (COMA) connected to a reference electrode (silver-silver chloride) was used for the P measurements. Measurements of A (at -900 mV) and P were made in an aqueous environment regulated for oxygen, pH, and temperature. Reproducible oxygen sensitivities of 0.925 nA/% oxygen (2% CV (coefficient of variation)) (A), 10.7 mV/% (P), and 0.7 mV/% (P) were found in the oxygen range: 0-21%, <5%, and above 5%, respectively. The pH sensitivity was 57 mV/pH unit (P). Oxygen and pH measurements were less accurate at oxygen concentrations close to 0%. Both the oxygen and pH part of the composite electrode signal can be identified by this dual mode technique (A and P). The sensor seems to be promising as it provides measurements of two separate variables (oxygen and pH) and also has the desirable characteristics of a solid state sensor.

  4. Development and pharmacokinetic of antimony encapsulated in liposomes of phosphatidylserine using radioisotopes in experimental leishmaniasis

    International Nuclear Information System (INIS)

    Borborema, Samanta Etel Treiger

    2010-01-01

    Leishmaniasis are a complex of parasitic diseases caused by intra macrophage protozoa of the genus Leishmania, and is fatal if left untreated. Pentavalent antimonials, though toxic and their mechanism of action being unclear, remain the first-line drugs for treatment. Effective therapy could be achieved by delivering antileishmanial drugs to these sites of infection. Liposomes are phospholipid vesicles that promote improvement in the efficacy and action of drugs in target cell. Liposomes are taken up by the cells of mononuclear phagocytic system (MPS). The purpose of this study was to develop a preparation of meglumine antimonate encapsulated in liposomes of phosphatidylserine and to study its pharmacokinetic in healthy mice to establish its metabolism and distribution. Quantitative analysis of antimony from liposomes demonstrated that Neutron Activation Analysis was the most sensitive technique with almost 100 % of accuracy. All liposome formulations presented a mean diameter size of 150 nm. The determination of IC 50 in infected macrophage showed that liposome formulations were between 10 - 63 fold more effective than the free drug, indicating higher selectivity index. By fluorescence microscopy, an increased uptake of fluorescent-liposomes was seen in infected macrophages during short times of incubation compared with non-infected macrophages. Biodistribution studies showed that meglumine antimonate irradiated encapsulated in liposomes of phosphatidylserine promoted a targeting of antimony for MPS tissues and maintained high doses in organs for a prolonged period. In conclusion, these data suggest that meglumine antimonate encapsulated in liposomes showed higher effectiveness than the non-liposomal drug against Leishmania infection. The development of liposome formulations should be a new alternative for the chemotherapy of infection diseases, especially Leishmaniasis, as they are used to sustain and target pharmaceuticals to the local of infection. (author)

  5. Pharmacokinetics and tissue distribution of Antimony after multiple intramuscular administrations in the Hamster

    International Nuclear Information System (INIS)

    Al-Jaser, May H.; Radwan, Mahasen A.; Zaghloul, Imam Y.

    2006-01-01

    The fate of pentavalent antimony (Sb) in different tissues in the body after intramuscular administration is of great interest for the future study of Sb therapy in different sitting. Pharmacokinetics and tissue distribution of antimony (Sb) were studied in the hamster after daily dose of sodium stibogluconate equivalent to 120 mg kg of Sb, administered intramuscularly for two weeks. Liver, spleen, heart, kidney and skin tissues were isolated after blood collection at the specified time. Antimony was measured in these tissues after suitable treatment, ashing and processing, by flame less atomic absorption spectrophotometry. The concentration of Sb time profile in blood showed a linear raid decline with elimination half life (tz1/2) of 1.7h. The concentration of drug (ug/gm) declined in a biphasic manner from almost all tissues. However, the concentrations of Sb were declined in slower fashion from the hamster tissues than from the blood. The maximum concentration of Sb was determined in the kidney tissues (3416+-631ug/gm) while the lowest concentration was in the spleen (209+-187ug/gm). The maximum concentration of Sb in the kidney (ug/gm) was more than 25 fold higher than that measured from blood (ug/ml). The AUC of Sb in the studied tissues was in this rank: kidney>liver>skin>spleen>heart>blood. Surprisingly, the heart, spleen and liver showed a similar t1/2 of 5.2-6.2h while the kidney and skin had a t1/2 of about 3h. Therefore, disposition of Sb seems to kinetically follow multicompartmental compartmental model. The kidneys got the highest concentration of drug which may lead to nephrotoxicity on long term therapy. (author)

  6. Antimony Adsorption from Zarshouran Gold Mineral Processing Plant Wastewater by Nano Zero Valent Iron Coated on Bentonite

    Directory of Open Access Journals (Sweden)

    nader nosrati

    2015-03-01

    Full Text Available The effluent from Zarshouran gold mineral processing plant contains high quantities of arsenic, antimony, mercury, and bismuth. These metals and metalloids are soluble in water and very toxic when they enter the environment. Their solubility in water causes the polluted area to extend beyond their point of origin. In this article, different methods of antimony removal from water and wastewater were reviewed and the zero-valent iron nanoparticles coated on Bentonite were selected as an effective and low cost material for removing antimony from wastewater. For the purposes of this study, zero-valent iron nanoparticles of 40-100 nanometers in size were synthesized by dropwise addition of sodium borohydride solution to an Iron (III aqueous solution at  ambient temperature and mixed with nitrogen gas. To avoid particle agglomeration and to enhance the product’s environmentally safe application, the  nanoparticles were coated on Bentonite and characterized by SEM/EDAX and BET. The experiments were carried out by intense mixing of the adsorbent with 10ml of real/synthtic wastewater samples in 20ml bottles.  The effects of pH, contact time, temperature, and adsorbent dosage on antimony removal efficiency were investigated under intense mixing using a magnetic mixer. Finally, the effluents were filtered upon completion of the experiments and used for atomic adsorption analysis. The results of the experiments showed that the adsorption isotherms of the synthesized nanoparticles obeyed the Langmuir and Freundlich models. The experiments carried out on real samples showed that antimony adsorption capacity for B-nZVI was 2.6 mg/g of the adsorbent and that the highest antimony removal efficiency was 99.56%.

  7. Photodegradation of Naphthol green B in the presence of semiconducting antimony trisulphide - SHORT COMMUNICATION

    Directory of Open Access Journals (Sweden)

    RAKSHIT AMETA

    2011-07-01

    Full Text Available Different methods of wastewater treatment are being used for the removal of dyes from their solution, but in most of the cases, either homogeneous catalysts or different adsorbents are used. These methods have their own merits and demerits. In the present work, antimony trisulphide was used as a heterogeneous catalyst. The effects of different parameters on the rate of the reaction were observed, such as pH, concentration of dye, amount of semiconductor and light intensity. A tentative mechanism is proposed in which the role of hydroxyl radical as an active oxidizing species is shown for degradation of Naphthol green B.

  8. Determination of arsenic, selenium and antimony by neutron activation analysis. Application to hair samples

    International Nuclear Information System (INIS)

    Das, H.A.; Hoede, D.; Nieuwendijk, B.J.T.; Sloot, H.A. van der; Teunissen, G.J.A.; Woittiez, J.R.W.

    1983-04-01

    A fast rabbit system for instrumental activation analysis with reactor neutrons is described. Its use in the determination of selenium in hair is discussed. A survey is given of the correction factors which are inherent to the use of short-lived radionuclides. An alternative to INAA is NAA based on the separation of arsenic, selenium and antimony by hydride evaporation and adsorption to active carbon. Data for some Standard Reference Materials are given. This work was done under research contract 2440/RI/RB with the IAEA

  9. Direct Band Gap Gallium Antimony Phosphide (GaSbxP1−x) Alloys

    OpenAIRE

    H. B. Russell; A. N. Andriotis; M. Menon; J. B. Jasinski; A. Martinez-Garcia; M. K. Sunkara

    2016-01-01

    Here, we report direct band gap transition for Gallium Phosphide (GaP) when alloyed with just 1?2 at% antimony (Sb) utilizing both density functional theory based computations and experiments. First principles density functional theory calculations of GaSbxP1?x alloys in a 216 atom supercell configuration indicate that an indirect to direct band gap transition occurs at x?=?0.0092 or higher Sb incorporation into GaSbxP1?x. Furthermore, these calculations indicate band edge straddling of the h...

  10. Screening of cesticidal compounds on a tapeworm hymenolepis nana in vitro

    Science.gov (United States)

    Sen, A. B.; Hawking, F.

    1960-01-01

    A simple and convenient in vitro technique is described for the screening of compounds for action against Hymenolepis nana and probably many other intestinal worms. The results obtained from this test are in broad agreement with the findings of clinical experience and of a small series of in vivo tests. Among the substances tested, the most active ones were oil of chenopodium, dichlorophen, extract of cashew nut (Anacardium occidentale), antimony potassium tartrate, and BIQ 20 [eicosamethylenebis(isoquinolinium iodide)]. PMID:13750047

  11. Mesoionic Compounds

    Indian Academy of Sciences (India)

    property has been used to determine whether a compound is aromatic or not. Mesoionic compounds are structurally very different from ben- zenoid compounds, but they fulfill most of the criteria of aroma- ticity and form a part of a variety of aromatic compounds, which can be classified as follows. A) Benzenoid Compounds.

  12. Structural and optical study on antimony-silicate glasses doped with thulium ions.

    Science.gov (United States)

    Dorosz, D; Zmojda, J; Kochanowicz, M; Miluski, P; Jelen, P; Sitarz, M

    2015-01-05

    Structural, spectroscopic and thermal properties of SiO₂-Al₂O₃-Sb₂O₃-Na₂O glass system doped with 0.2 mol% Tm₂O₃ have been presented. Synthesis of antimony-silicate glasses with relatively low phonon energy (600 cm(-1), which implicates a small non-radiative decay rate) was performed by conventional high-temperature melt-quenching methods. The effect of SiO₂/Sb₂O₃ ratio in fabricated Tm(3+) doped glass on thermal, structural and luminescence properties was investigated. On the basis of structural investigations decomposition of absorption bands in the infrared FTIR region was performed, thus determining that antimony ions are the only glass-forming ions, setting up the lattice of fabricated glasses. Luminescence band at the wavelength of 1.8 μm corresponding to (3)F₄→(3)H₆ transition in thulium ions was obtained under 795 nm laser pumping. It was observed that combination of relatively low phonon energy and greater separation of optically active centers in the fabricated glasses influenced in decreasing the luminescence intensity at 1800 nm. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Determination of Trace Antimony (III by Adsorption Voltammetry at Carbon Paste Electrode

    Directory of Open Access Journals (Sweden)

    Nongyue He

    2005-05-01

    Full Text Available This work presents a sensitive method for the determination of trace antimonybased on the antimony-pyrogallol red (PGR adsorption at a carbon paste electrode (CPE.The optimal conditions were to use an electrode containing 25% paraffin oil and 75%high purity graphite powder as working electrode, a 0.10 mol/L HCl solution containing3.0×10-5 mol/L PGR as accumulation medium and a 0.20 mol/L HCl solution aselectrolyte with an accumulation time of 150 s and a reduction time of 60 s at -0.50 Vfollowed with a sweep from -0.50 V to 0.20 V. The mechanism of the electrode reactionwas discussed. Interferences of other metal ions were studied as well. The detection limitwas 1×10-9 mol/L. The linear range was from 2.0×10-9 mol/L to 5.0×10-7 mol/L.Application of the proposed method to the determination of antimony in water andhuman hair samples gave good results.

  14. Migration of antimony from PET containers into regulated EU food simulants.

    Science.gov (United States)

    Sánchez-Martínez, María; Pérez-Corona, Teresa; Cámara, Carmen; Madrid, Yolanda

    2013-11-15

    Antimony migration from polyethylene terephthalate (PET) containers into aqueous (distilled water, 3% acetic acid, 10% and 20% ethanol) and fatty food simulants (vegetable oil), as well as into vinegar, was studied. Test conditions were according to the recent European Regulation 10/2011 (EU, 2011). Sb migration was assayed by ICP-MS and HG-AFS. The results showed that Sb migration values ranged from 0.5 to 1.2μg Sb/l, which are far below the maximum permissible migration value for Sb, 40μg Sb/kg, (EU, Regulation 10/2011). Parameters as temperature and bottle re-use influence were studied. To assess toxicity, antimony speciation was performed by HPLC-ICP-MS and HG-AFS. While Sb(V) was the only species detected in aqueous simulants, an additional species (Sb-acetate complex) was measured in wine vinegar. Unlike most of the studies reported in the literature, migration tests were based on the application of the EU directive, which enables comparison and harmonisation of results. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Antimonial Therapy Induces Circulating Proinflammatory Cytokines in Patients with Cutaneous Leishmaniasis

    Science.gov (United States)

    Kocyigit, Abdurrahim; Gur, Selahaddin; Gurel, Mehmet S.; Bulut, Vedat; Ulukanligil, Mustafa

    2002-01-01

    The objective of this study was to evaluate the association between antimonial therapy and circulating levels of proinflammatory cytokines in patients with cutaneous leishmaniasis (CL). Patients were treated with conventional chemotherapy by using pentavalent antimonium salts (Glucantime) for 3 weeks. Circulating plasma levels of the proinflammatory cytokines interleukin-1β (IL-1β), IL-6, IL-8, and tumor necrosis factor alpha (TNF-α) were determined for CL patients and healthy subjects before and 3 weeks after the treatment was started. Plasma IL-1β, IL-6, IL-8, and TNF-α levels were significantly higher for pretreatment CL patients than for healthy subjects. Proinflammatory cytokines significantly increased after 21 days postinfection compared to levels for the pretreatment patients. These increments were approximately 3-fold for IL-1β and TNF-α levels, 10-fold for IL-6 levels, and 20-fold for IL-8 levels in patients with CL. Taken together these results indicate that circulating proinflammatory cytokine levels were increased in patients with CL as a consequence of host defense strategies, and antimonial therapy may induce these cytokines by affecting the macrophage or other components of the host defense system. PMID:12438329

  16. Meglumine antimoniate is more effective than sodium stibogluconate in the treatment of cutaneous leishmaniasis.

    Science.gov (United States)

    Yesilova, Yavuz; Surucu, Hacer Altın; Ardic, Nurittin; Aksoy, Mustafa; Yesilova, Abdullah; Oghumu, Steve; Satoskar, Abhay R

    2016-01-01

    Sodium stibogluconate (SSG, Pentostam) and meglumine antimoniate (MA, Glucantime) are two antimonials that are widely used to treat cutaneous leishmaniasis (CL), but the relative efficacies of these treatments are not clear. The aim of this study is to compare the efficacy of intralesional SSG with intralesional MA therapy in the treatment of CL. One month after completion of the therapy, 1431 of 1728 patients (82%) who received intralesional MA showed complete clinical cure compared to 1157 of 1728 patients (67%) in the SSG group. Patients who did not respond to the first round of therapy were re-administered the same treatment but with twice weekly injections. Following completion of the second course of therapy, 237 of 297 patients (80%) in the MA group and 407 of 561 patients (72%) in the SSG group healed their lesions by 1-month post-treatment. At both times, the differences in cure rates between MA and SSG groups were statistically significant (p < 0.05). Cure rates in the MA group were always significantly higher than SSG groups irrespective of other parameters including age, gender, lesion site and type of lesion. Intralesional MA is more effective than intralesional SSG in the treatment of CL.

  17. Growth of antimony doped P-type zinc oxide nanowires for optoelectronics

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhong Lin; Pradel, Ken

    2016-09-27

    In a method of growing p-type nanowires, a nanowire growth solution of zinc nitrate (Zn(NO.sub.3).sub.2), hexamethylenetetramine (HMTA) and polyethylenemine (800 M.sub.w PEI) is prepared. A dopant solution to the growth solution, the dopant solution including an equal molar ration of sodium hydroxide (NaOH), glycolic acid (C.sub.2H.sub.4O.sub.3) and antimony acetate (Sb(CH.sub.3COO).sub.3) in water is prepared. The dopant solution and the growth solution combine to generate a resulting solution that includes antimony to zinc in a ratio of between 0.2% molar to 2.0% molar, the resulting solution having a top surface. An ammonia solution is added to the resulting solution. A ZnO seed layer is applied to a substrate and the substrate is placed into the top surface of the resulting solution with the ZnO seed layer facing downwardly for a predetermined time until Sb-doped ZnO nanowires having a length of at least 5 .mu.m have grown from the ZnO seed layer.

  18. High levels of antimony in dust from e-waste recycling in southeastern China

    International Nuclear Information System (INIS)

    Bi, Xiangyang; Li, Zhonggen; Zhuang, Xiaochun; Han, Zhixuan; Yang, Wenlin

    2011-01-01

    Environmental contamination due to uncontrolled e-waste recycling is an emerging global issue. Antimony (Sb) is a toxic element used in semiconductor components and flame retardants for circuit board within electronic equipment. When e-waste is recycled, Sb is released and contaminates the surrounding environment; however, few studies have characterized the extent of this problem. In this study, we investigated Sb and arsenic (As) distributions in indoor dust from 13 e-waste recycling villages in Guiyu, Guangdong Province, southeastern China. Results revealed significantly elevated concentrations of Sb (6.1-232 mg/kg) in dust within all villages, which were 3.9-147 times higher than those from the non e-waste sites, indicating e-waste recycling was an important source of Sb pollution. On the contrary, As concentrations (5.4-17.7 mg/kg) in e-waste dusts were similar to reference values from the control sites. Therefore, dusts emitted from e-waste recycling may be characterized by high Sb/As ratios, which may help identify the contamination due to the e-waste recycling activities. - Highlights: → Antimony and arsenic concentrations in dust from e-waste recycling were investigated. → E-waste recycling is an important emerging source of Sb pollution. → Sb/As ratios may help identify the e-waste contamination.

  19. Antimony trioxide-induced apoptosis is dependent on SEK1/JNK signaling.

    Science.gov (United States)

    Mann, Koren K; Davison, Kelly; Colombo, Myrian; Colosimo, April L; Diaz, Zuanel; Padovani, Alessandra M S; Guo, Qi; Scrivens, P James; Gao, Wenli; Mader, Sylvie; Miller, Wilson H

    2006-01-05

    Very little is known concerning the toxicity of antimony, despite its commercial use as a flame retardant and medical use as a treatment for parasitic infections. Our previous studies show that antimony trioxide (Sb(2)O(3)) induces growth inhibition in patient-derived acute promyelocytic leukemia (APL) cell lines, a disease in which a related metal, arsenic trioxide (As(2)O(3)), is used clinically. However, signaling pathways initiated by Sb(2)O(3) treatment remain undefined. Here, we show that Sb(2)O(3) treatment of APL cells is associated with increased apoptosis as well as differentiation markers. Sb(2)O(3)-induced reactive oxygen species (ROS) correlated with increased apoptosis. In addition, when we decreased the buffering capacity of the cell by depleting glutathione, ROS production and apoptosis was enhanced. Arsenic-resistant APL cells with increased glutathione levels exhibited increased cross-resistance to Sb(2)O(3). Based on studies implicating c-jun kinase (JNK) in the mediation of the response to As(2)O(3), we investigated the role for JNK in Sb(2)O(3)-induced apoptosis. Sb(2)O(3) activates JNK and its downstream target, AP-1. In fibroblasts with a genetic deletion in SEK1, an upstream regulator of JNK, Sb(2)O(3)-induced growth inhibition as well as JNK activation was decreased. These data suggest roles for ROS and the SEK1/JNK pathway in the cytotoxicity associated with Sb(2)O(3) exposure.

  20. Leaching of the antimony and accompanying of elements Sb2S3 in the alkaline medium

    Directory of Open Access Journals (Sweden)

    Dagmar Remeteiová

    2007-06-01

    Full Text Available This paper presents results of the laboratory investigation of alkaline leaching of stibnite that is an important mineral occuring in the antimony-bearing raw materials. The following components were present in stibnite: Sb2S3, SiO2, ZnS, FeS2. The aim of this study was to establish the effect of composition of the aqueous alkaline leaching medium (1 % NaOH, 1 % NaOH + 1 % Na2S2O3, 1 % NaOH + 1 % Na2S on the recoveries of Sb, Fe, Pb, Zn, Cu, Ni and Hg. The antimony recoveries in the leaching solutions NaOH and NaOH + Na2S2O3 solutions were lower in comparison with the leaching in NaOH + Na2S. The Fe, Pb, Zn recoveries in alkaline solutions were found to decrease in the following order: Fe, Pb, Zn. The mercury recovery in the leaching test with the solution containing 1 % NaOH+1 % Na2S was 3,7 %.

  1. Evaluation of antimony microparticles supported on biochar for application in the voltammetric determination of paraquat.

    Science.gov (United States)

    Gevaerd, Ava; de Oliveira, Paulo R; Mangrich, Antonio S; Bergamini, Márcio F; Marcolino-Junior, Luiz H

    2016-05-01

    This work describes the construction and application of carbon paste electrodes modified with biochar and antimony microparticles (SbBCPE) for voltammetric determination of paraquat using a simple and sensitive procedure based on voltammetric stripping analysis. Some parameters such as amount of biochar and antimony used in the composition of the carbon paste and instrumental parameters were examined in detail. Under optimized conditions, an analytical curve was obtained for paraquat determination employing SbBCPE, which showed a linear response ranging from 0.2 to 2.9 μmol L(-1), with limit of detection and quantification of 34 nmol L(-1) and 113 nmol L(-1), respectively, after paraquat pre-concentration of 120 s. The repeatability study presented a RSD=2.0% for 10 consecutive measurements using the same electrode surface and the reproducibility study showed a RSD=2.7% for measurements with 10 different electrode surfaces. The proposed sensor was successfully applied for paraquat determination in tap water and citric fruit juice spiked samples and good recoveries were obtained without any sample pre-treatment, showing its promising analytical performance. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Determination of antimony in nail and hair by thermal neutron activation analysis

    International Nuclear Information System (INIS)

    Katayama, Yukio; Ishida, Norio

    1987-01-01

    The concentration of antimony in nail and hair was determined by thermal neutron activation analysis. Samples were collected from the workers of an antimony refinery, inhabitants near the refinery, and residents in control area. They were irradiated by Kyoto University 5000 kW Reactor for 1 h, and cooled for 30 to 100 days. After cooling, the concentration of Sb in nail and hair was estimated by measuring the intensity of γ-ray from 124 Sb of the samples, then the samples were washed by 0.1 % aqueous solution of nonionic surface active agent in an ultrasonic cleaner. The γ-ray spectrometry was done again (after washing). The concentration of Sb in nail before washing was 730 ppm for the workers, 2.46 ppm for habitants near the refinery, and 0.19 ppm for the control; after washing, it became 230 ppm for the workers, 0.63 ppm for habitants, and 0.09 ppm for the control. The concentration of Sb in hair before and after washing was 222 ppm and 196 ppm for the workers, and 0.21 ppm and 0.15 ppm for the control, respectively. (author)

  3. Distributions and impact factors of antimony in topsoils and moss in Ny-Ålesund, Arctic

    International Nuclear Information System (INIS)

    Jia Nan; Sun Liguang; He Xin; You Kehua; Zhou Xin; Long Nanye

    2012-01-01

    The distribution of antimony (Sb) in topsoil and moss (Dicranum angustum) in disturbed and undisturbed areas, as well as coal and gangue, in Ny-Ålesund, Arctic was examined. Results show that the weathering of coal bed could not contribute to the increase of Sb concentrations in topsoil and moss in the study area. The distribution of Sb is partially associated with traffic and historical mining activities. The occurrence of the maximum Sb concentration is due to the contribution of human activities. In addition, the decrease of Sb content in topsoil near the coastline may be caused by the washing of seawater. Compared with topsoils, moss could be a useful tool for monitoring Sb in both highly and lightly polluted areas. - Highlights: ► We examined the distribution of antimony in topsoil and moss in Ny-Ålesund, Arctic. ► The distribution of Sb is associated with traffic and historical mining activities. ► The weathering of coal bed cannot lead to the Sb increase in the surface environment. ► The distribution of Sb in moss could reflect the accumulation of Sb pollution. ► Moss can be a useful tool for monitoring Sb in highly and lightly polluted areas. - The distribution of Sb in Ny-Ålesund is partially associated with traffic and historical mining activities, and moss can be a useful tool for monitoring Sb in both highly and lightly polluted areas.

  4. Glass and antimony electrodes for long-term pH monitoring: a dynamic in vitro comparison

    NARCIS (Netherlands)

    Geus, W. P.; Smout, A. J.; Kooiman, J. C.; Lamers, C. B.; Gues, J. W.

    1995-01-01

    OBJECTIVE: To compare the performance of combined glass microelectrodes with monocrystalline and polycrystalline antimony electrodes with external reference in a 24-h dynamic in vitro study. DESIGN AND METHODS: In an artificial stomach, the pH of the contents titrated from pH1-7 and back by NaOH and

  5. Ambulatory oesophageal pH monitoring: a comparison between antimony, ISFET, and glass pH electrodes

    NARCIS (Netherlands)

    Hemmink, Gerrit J. M.; Weusten, Bas L. A. M.; Oors, Jac; Bredenoord, Albert J.; Timmer, Robin; Smout, André J. P. M.

    2010-01-01

    BACKGROUND AND AIM: Ambulatory oesophageal pH-impedance monitoring is a widely used test to evaluate patients with reflux symptoms. Several types of pH electrodes are available: antimony, ion sensitive field effect transistor (ISFET), and glass electrodes. These pH electrodes have not been compared

  6. Health and ecological risk assessment of heavy metals pollution in an antimony mining region: a case study from South China.

    Science.gov (United States)

    Fei, Jiang-Chi; Min, Xiao-Bo; Wang, Zhen-Xing; Pang, Zhi-Hua; Liang, Yan-Jie; Ke, Yong

    2017-12-01

    In recent years, international research on the toxicity of the heavy metal, antimony, has gradually changed focus from early medical and pharmacological toxicology to environmental toxicology and ecotoxicology. However, little research has been conducted for sources identification and risk management of heavy metals pollution by long-term antimony mining activities. In this study, a large number of investigations were conducted on the temporal and spatial distribution of antimony and related heavy metal contaminants (lead, zinc, and arsenic), as well as on the exposure risks for the population for the Yuxi river basin in the Hunan province, China. The scope of the investigations included mine water, waste rock, tailings, agricultural soil, surface water, river sediments, and groundwater sources of drinking water. Health and ecological risks from exposure to heavy metal pollution were evaluated. The main pollution sources of heavy metals in the Yuxi River basin were analyzed. Remediation programs and risk management strategies for heavy metal pollution were consequently proposed. This article provides a scientific basis for the risk assessment and management of heavy metal pollution caused by antimony basin ore mining.

  7. Comparative phytotoxicity of methylated and inorganic arsenic- and antimony species to Lemna minor, Wolffia arrhiza and Selenastrum capricornutum

    NARCIS (Netherlands)

    Duester, L.; van der Geest, H.G.; Moelleken, S.; Hirner, A.V.; Kueppers, K.

    2011-01-01

    The alkylation of metalloids through the transfer of methyl groups is an important factor in the biogeochemical cycling of elements like arsenic and antimony. In the environment, many different organic and inorganic forms of these elements can therefore be found in soils, sediments or organisms.

  8. Effect of Annealing on the Properties of Antimony Telluride Thin Films and Their Applications in CdTe Solar Cells

    Directory of Open Access Journals (Sweden)

    Zhouling Wang

    2014-01-01

    Full Text Available Antimony telluride alloy thin films were deposited at room temperature by using the vacuum coevaporation method. The films were annealed at different temperatures in N2 ambient, and then the compositional, structural, and electrical properties of antimony telluride thin films were characterized by X-ray fluorescence, X-ray diffraction, differential thermal analysis, and Hall measurements. The results indicate that single phase antimony telluride existed when the annealing temperature was higher than 488 K. All thin films exhibited p-type conductivity with high carrier concentrations. Cell performance was greatly improved when the antimony telluride thin films were used as the back contact layer for CdTe thin film solar cells. The dark current voltage and capacitance voltage measurements were performed to investigate the formation of the back contacts for the cells with or without Sb2Te3 buffer layers. CdTe solar cells with the buffer layers can reduce the series resistance and eliminate the reverse junction between CdTe and metal electrodes.

  9. American cutaneous leishmaniasis caused by Leishmania (Viannia braziliensis resistant to meglumine antimoniate, but with good response to pentamidine: a case report

    Directory of Open Access Journals (Sweden)

    Maria Inês Fernandes Pimentel

    2011-04-01

    Full Text Available This is a case report of a Brazilian soldier with cutaneous leishmaniasis. The lesion relapsed following two systemic treatments with meglumine antimoniate. The patient was treated with amphotericin B, which was interrupted due to poor tolerance. Following isolation of Leishmania sp., six intralesional infiltrations of meglumine antimoniate resulted in no response. Leishmania sp promastigotes were again isolated. The patient was submitted to intramuscular 4mg/kg pentamidine. Parasites from the first and second biopsies were identified as Leishmania (Viannia braziliensis; those isolated from the first biopsy were more sensitive to meglumine antimoniate in vitro than those isolated from the second biopsy. No relapse was observed.

  10. Speciation of Sb(III) and Sb(V) in meglumine antimoniate pharmaceutical formulations by PSA using carbon nanotube electrode.

    Science.gov (United States)

    Santos, Vivian Silva; Santos, Wilney de Jesus Rodrigues; Kubota, Lauro Tatsuo; Tarley, César Ricardo Teixeira

    2009-09-08

    A new and simple electroanalytical method for speciation of Sb(III) and Sb(V) in pharmaceutical formulation by potentiometric stripping analysis (PSA) using a multiwall carbon nanotube paste electrode was developed. All instrumental and chemical parameters influencing the performance of the method were carefully assessed and optimized. Trivalent antimony was determined in acid medium (pH 3.6) under the optimized condition (deposition potential of -0.7 V, deposition time of 180 s, ionic strength of 0.3M and oxidant mercury concentration of 10 mg l(-1)). Total antimony was determined after quantitative reduction of Sb(V) with l-cysteine (1.5%, w/v) and its concentration was calculated from difference between the total antimony and Sb(III). The developed method provided two distinct linear calibration one ranging from 10 up to 50 microg l(-1) and other from 100 up to 800 microg l(-1) with respective correlation coefficient of 0.9978 and 0.9993, presenting a detection limit of 6.2 microg l(-1). Repeatability for the six independent samples expressed in terms of relative standard deviation was found to be 3.01 and 1.39% for 40.0 and 300.0 microg l(-1) antimony concentration, respectively. Results on the effect of foreign substances [Al(III), Mg(II), Fe(III), Cd(II), Zn(II) and meglumine] on analytical signal of antimony showed no interference even using high content of foreign ions in the analyte:interferent ratio up to 1:100. The proposed method was successfully applied for the speciation of Sb(III) and Sb(V) in pharmaceutical formulation and the accuracy was assessed from addition and recovery tests as well as comparing with graphite furnace atomic absorption spectrometry (GF AAS) technique used as reference analytical method.

  11. Lithium-antimony-lead liquid metal battery for grid-level energy storage.

    Science.gov (United States)

    Wang, Kangli; Jiang, Kai; Chung, Brice; Ouchi, Takanari; Burke, Paul J; Boysen, Dane A; Bradwell, David J; Kim, Hojong; Muecke, Ulrich; Sadoway, Donald R

    2014-10-16

    The ability to store energy on the electric grid would greatly improve its efficiency and reliability while enabling the integration of intermittent renewable energy technologies (such as wind and solar) into baseload supply. Batteries have long been considered strong candidate solutions owing to their small spatial footprint, mechanical simplicity and flexibility in siting. However, the barrier to widespread adoption of batteries is their high cost. Here we describe a lithium-antimony-lead liquid metal battery that potentially meets the performance specifications for stationary energy storage applications. This Li||Sb-Pb battery comprises a liquid lithium negative electrode, a molten salt electrolyte, and a liquid antimony-lead alloy positive electrode, which self-segregate by density into three distinct layers owing to the immiscibility of the contiguous salt and metal phases. The all-liquid construction confers the advantages of higher current density, longer cycle life and simpler manufacturing of large-scale storage systems (because no membranes or separators are involved) relative to those of conventional batteries. At charge-discharge current densities of 275 milliamperes per square centimetre, the cells cycled at 450 degrees Celsius with 98 per cent Coulombic efficiency and 73 per cent round-trip energy efficiency. To provide evidence of their high power capability, the cells were discharged and charged at current densities as high as 1,000 milliamperes per square centimetre. Measured capacity loss after operation for 1,800 hours (more than 450 charge-discharge cycles at 100 per cent depth of discharge) projects retention of over 85 per cent of initial capacity after ten years of daily cycling. Our results demonstrate that alloying a high-melting-point, high-voltage metal (antimony) with a low-melting-point, low-cost metal (lead) advantageously decreases the operating temperature while maintaining a high cell voltage. Apart from the fact that this

  12. Novel antimony doped tin oxide/carbon aerogel as efficient electrocatalytic filtration membrane

    Directory of Open Access Journals (Sweden)

    Zhimeng Liu

    2016-05-01

    Full Text Available A facile method was developed to prepare antimony doped tin oxide (Sb-SnO2/carbon aerogel (CA for use as an electrocatalytic filtration membrane. The preparation process included synthesis of a precursor sol, impregnation, and thermal decomposition. The Sb-SnO2, which was tetragonal in phase with an average crystallite size of 10.8 nm, was uniformly distributed on the CA surface and firmly attached via carbon-oxygen-tin chemical bonds. Preliminary filtration tests indicated that the Sb-SnO2/CA membrane had a high rate of total organic carbon removal for aqueous tetracycline owing to its high current efficiency and electrode stability.

  13. Synthesis and optical properties of antimony oxide glasses doped with holmium trioxide

    Energy Technology Data Exchange (ETDEWEB)

    Raghunatha, S.; Eraiah, B., E-mail: eraiah@rediffmail.com [Department of physics, Bangalore University, Bengaluru – 560 056. India (India)

    2016-05-06

    Holmium doped lithium-antimony-lead borate glasses having 1 mol% AgNO{sub 3} with composition 50B{sub 2}O{sub 3}-20PbO-25Sb{sub 2}O{sub 3}-5Li{sub 2}O have been prepared using single step melt quenching technique. The XRD spectrum confirms amorphous nature of glasses. The optical absorbance studies were carried out on these glasses. The optical direct band gap energies were found to be in the range of 3.10 eV to 3.31 eV and indirect band gap energies were found to be in the range of 2.28 eV to 3.00 eV. The refractive indexes have been calculated by using Lorentz-Lorenz formula and the calculated values in the range of 2.31 to 2.37.

  14. Mid-infrared optical properties of chalcogenide glasses within tin-antimony-selenium ternary system.

    Science.gov (United States)

    Lin, Ruiqiang; Chen, Feifei; Zhang, Xiaoyu; Huang, Yicong; Song, Baoan; Dai, Shixun; Zhang, Xianghua; Ji, Wei

    2017-10-16

    In this work, we investigated the mid-infrared (MIR) optical properties of selenide (Se-based) chalcogenide glasses (ChGs) within an As- and Ge-free system, namely the environment-friendly and low-cost tin-antimony-selenium (Sn-Sb-Se, SSS) ternary system, which has not been systematically studied to the best of our knowledge. As compared to ChGs within those conventional Se-based systems, SSS ChGs were found to exhibit extended infrared transmittance range as well as larger linear refractive index (n 0 ). Femtosecond Z-scan measurements show the presence of evident three-photon absorption from Urbach absorption of the SSS ChGs at MIR wavelength, which resonantly enhanced the nonlinear refractive behavior and resulted in large nonlinear refractive index (n 2 ).

  15. Microbial diversity and community structure in an antimony-rich tailings dump.

    Science.gov (United States)

    Xiao, Enzong; Krumins, Valdis; Dong, Yiran; Xiao, Tangfu; Ning, Zengping; Xiao, Qingxiang; Sun, Weimin

    2016-09-01

    To assess the impact of antimony (Sb) on microbial community structure, 12 samples were taken from an Sb tailings pile in Guizhou Province, Southwest China. All 12 samples exhibited elevated Sb concentrations, but the mobile and bioaccessible fractions were small in comparison to total Sb concentrations. Besides the geochemical analyses, microbial communities inhabiting the tailing samples were characterized to investigate the interplay between the microorganisms and environmental factors in mine tailings. In all samples, Proteobacteria and Actinobacteria were the most dominant phyla. At the genus level, Thiobacillus, Limnobacter, Nocardioides, Lysobacter, Phormidium, and Kaistobacter demonstrated relatively high abundances. The two most abundant genera, Thiobacillus and Limnobacter, are characterized as sulfur-oxidizing bacteria and thiosulfate-oxidizing bacteria, respectively, while the genus Lysobacter contains arsenic (As)-resistant bacteria. Canonical correspondence analysis (CCA) indicates that TOC and the sulfate to sulfide ratio strongly shaped the microbial communities, suggesting the influence of the environmental factors in the indigenous microbial communities.

  16. The electronic structure of the antimony chalcogenide series: Prospects for optoelectronic applications

    International Nuclear Information System (INIS)

    Carey, John J.; Allen, Jeremy P.; Scanlon, David O.; Watson, Graeme W.

    2014-01-01

    In this study, density functional theory is used to evaluate the electronic structure of the antimony chalcogenide series. Analysis of the electronic density of states and charge density shows that asymmetric density, or ‘lone pairs’, forms on the Sb III cations in the distorted oxide, sulphide and selenide materials. The asymmetric density progressively weakens down the series, due to the increase in energy of valence p states from O to Te, and is absent for Sb 2 Te 3 . The fundamental and optical band gaps were calculated and Sb 2 O 3 , Sb 2 S 3 and Sb 2 Se 3 have indirect band gaps, while Sb 2 Te 3 was calculated to have a direct band gap at Γ. The band gaps are also seen to reduce from Sb 2 O 3 to Sb 2 Te 3 . The optical band gap for Sb 2 O 3 makes it a candidate as a transparent conducting oxide, while Sb 2 S 3 and Sb 2 Se 3 have suitable band gaps for thin film solar cell absorbers. - Graphical abstract: A schematic illustrating the interaction between the Sb III cations and the chalcogenide anions and the change in their respective energy levels down the series. - Highlights: • The electronic structure of the antimony chalcogenide series is modelled using DFT. • Asymmetric density is present on distorted systems and absent on the symmetric telluride system. • Asymmetric density is formed from the mixing of Sb 5s and anion p states, where the anti-bonding combination is stabilised by the Sb 5p states. • The asymmetric density weakens down the series due to the increase in energy of chalcogenide p states. • The increase in energy of the anion p states reduces the fundamental and optical band gaps

  17. Successful treatment of feline leishmaniosis using a combination of allopurinol and N-methyl-glucamine antimoniate

    Directory of Open Access Journals (Sweden)

    Maria Alexandra Basso

    2016-02-01

    Full Text Available Case summary This work describes the diagnosis and successful treatment of a 2-year-old domestic cat infected with Leishmania species and presenting fever, and ulcerative and nodular skin lesions after being treated for pyodermatitis for 1 year without clinical improvement. After anamnesis the cat was submitted to a complete clinical examination. Blood was collected for determination of haematological and biochemical parameters, detection of feline leukaemia virus (FeLV, feline immunodeficiency virus (FIV, feline coronavirus (FCoV and Leishmania amastigotes. Fine-needle aspiration puncture from the skin nodules was also performed. After definitive diagnosis the animal was treated and followed up over a 2 year period. The animal tested negative for FIV-specific antibodies, FeLV antigen and feline coronavirus RNA. Leishmania amastigotes in the skin nodules were confirmed by cytology and molecular diagnosis. Treatment was initiated with allopurinol, resulting in a slight clinical improvement. Thus, N-methyl-glucamine antimoniate was added and administered for 30 days, with complete closure of the ulcerative lesions in the hindlimbs requiring a surgical approach. Close monitoring of the patient in the following 24 months indicated that combined therapy was safe and clinical cure was achieved without further relapses or side effects. Relevance and novel information Considering the increasing number of feline leishmaniosis cases and the inconsistent results of most therapeutic protocols described in the literature, the use of new approaches, especially in refractory cases, is essential. Although the use of allopurinol and N-methyl-glucamine antimoniate is off-label in cats, in this case the combination treatment was followed by an extensive analytical monitoring, supporting their safety and effectiveness.

  18. Toxicity Assessments of Antimony, Barium, Beryllium, and Manganese for Development of Ecological Soil Screening Levels (ECO-SSL) Using Earthworm (Eisenia Fetida) Benchmark Values

    National Research Council Canada - National Science Library

    Simini, Michael

    2002-01-01

    ... soil that supports relatively high bioavailability of barium (Ba), beryllium (Be), manganese (Mn), and antimony (Sb). For the metals tested, cocoon production was a more sensitive endpoint than was survival...

  19. Differential pulse polarographic determination of trace antimony in standard biological samples after preconcentration using 2-nitroso-1-naphthol-4-sulfonic acid

    International Nuclear Information System (INIS)

    Taher, M. A.

    2003-01-01

    A highly selective, rapid and economical differential polarographic method has been developed for the determination of trace amounts of antimony in various standard alloys and biological samples after of its 2-naphthol-4 sulfonic acid tetradecyl dimethylbenzylammonium chloride on microcrystalline naphthalene in the ph range of 7.5-11.0. After filtration, the solid mass is shaken with 8-10 ml of 1 M hydrochloric acid (with preconcentration factor of 10) and antimony is determined by differential pulse polarography. Antimony can alternatively be quantitatively absorbed on 2-nitroso-1-naphthol-4-sulfonic acid tetradecyl dimethylbenzylammonium-naphthalene absorbed packed in a column (with preconcentration factor of 30) and determined similarly. In this case, 1.5 μg of antimony can be concentrated in a column from 300 ml of aqueous sample, where its concentration is as low as 5 ng/ml. Characterization of the electro active process included an examination of the degree of reversibility. The results show that the irreversibility of antimony. Various parameters such as the effect of ph, volume of aqueous phase, HCl concentration, reagent concentration, naphthalene concentration, shaking time and interference of a number of metal ions on the determination of antimony have been studied in detail to optimize the conditions for determination in standard alloys and standard biological samples

  20. Remediation of antimony-rich mine waters: Assessment of antimony removal and shifts in the microbial community of an onsite field-scale bioreactor.

    Science.gov (United States)

    Sun, Weimin; Xiao, Enzong; Kalin, Margarete; Krumins, Valdis; Dong, Yiran; Ning, Zengping; Liu, Tong; Sun, Min; Zhao, Yanlong; Wu, Shiliang; Mao, Jianzhong; Xiao, Tangfu

    2016-08-01

    An on-site field-scale bioreactor for passive treatment of antimony (Sb) contamination was installed downstream of an active Sb mine in Southwest China, and operated for one year (including a six month monitoring period). This bioreactor consisted of five treatment units, including one pre-aerobic cell, two aerobic cells, and two microaerobic cells. With the aerobic cells inoculated with indigenous mine water microflora, the bioreactor removed more than 90% of total soluble Sb and 80% of soluble antimonite (Sb(III)). An increase in pH and decrease of oxidation-reduction potential (Eh) was also observed along the flow direction. High-throughput sequencing of the small subunit ribosomal RNA (SSU rRNA) gene variable (V4) region revealed that taxonomically diverse microbial communities developed in the bioreactor. Metal (loid)-oxidizing bacteria including Ferrovum, Thiomonas, Gallionella, and Leptospirillum, were highly enriched in the bioreactor cells where the highest total Sb and Sb(III) removal occurred. Canonical correspondence analysis (CCA) indicated that a suite of in situ physicochemical parameters including pH and Eh were substantially correlated with the overall microbial communities. Based on an UPGMA (Unweighted Pair Group Method with Arithmetic Mean) tree and PCoA (Principal Coordinates Analysis), the microbial composition of each cell was distinct, indicating these in situ physicochemical parameters had an effect in shaping the indigenous microbial communities. Overall, this study was the first to employ a field-scale bioreactor to treat Sb-rich mine water onsite and, moreover, the findings suggest the feasibility of the bioreactor in removing elevated Sb from mine waters. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. A Flow Method for Chemiluminescence Determination of Antimony(III) and Antimony(V) Using a Rhodamine B-Cetyltrimethylammonium Chloride Reversed Micelle System Following On-Line Extraction.

    Science.gov (United States)

    Hasanin, Tamer H A; Yamamoto, Tomoyuki; Okamoto, Yasuaki; Ishizaka, Shoji; Fujiwara, Terufumi

    2016-01-01

    A rapid and sensitive flow method, based on the combination of on-line solvent extraction with reversed micellar mediated chemiluminescence (CL) detection using rhodamine B (RB), was developed for the determination of antimony(III) and antimony(V) in aqueous samples. The on-line extraction procedure involved ion-pair formation of the antimony(V) chloro-complex anion with the protonated RBH(+) ion and its extraction from an aqueous hydrochloric acid solution into toluene, followed by phase separation using a microporous membrane. When in a flow cell of a detector, the ion-pair in the extract driven was mixed with the reversed micellar solution of cetyltrimethylammonium chloride in 1-hexanol-cyclohexane/water (0.60 mol dm(-3) H2SO4) containing cerium(IV), its uptake by the reversed micelles and the subsequent CL oxidation of RB with Ce(IV) occurred easily, then the produced CL signal was measured. Using the proposed flow method under the optimized experimental conditions, a detection limit (DL) of 0.35 μmol dm(-3) and a linear calibration graph with a dynamic range from DL to 16 μmol dm(-3) were obtained for Sb(V) with a precision of 1.4% relative standard deviation (n = 5) at the Sb(V) concentration of 8.2 μmol dm(-3). The present method was successfully applied to the determination of Sb(V) in water samples and to the differential determination of Sb(III) and Sb(V) in copper electrolyte industrial samples, where total antimony Sb(III) + Sb(V) was determined after oxidation of Sb(III) to Sb(V) with Ce(IV) and Sb(III) was calculated by difference, for which the DL was almost the same as that for Sb(V).

  2. First report of the use of meglumine antimoniate for treatment of canine leishmaniasis in a pregnant dog.

    Science.gov (United States)

    Spada, Eva; Proverbio, Daniela; Groppetti, Debora; Perego, Roberta; Grieco, Valeria; Ferro, Elisabetta

    2011-01-01

    Canine leishmaniasis during pregnancy is rarely reported, even in countries where the infection in dogs is endemic. The authors report a case of a 4 yr old bitch with leishmaniasis treated with meglumine antimoniate during pregnancy. The pregnancy and delivery were normal and the bitch presented improvement of the infection during treatment. Three puppies died within 2 days of birth and tested negative via real-time PCR for L. infantum. The two surviving puppies were followed clinically, serologically, and by real-time PCR until 1 yr of age with no evidence of congenital leishmaniasis. L. infantum DNA was detected with real-time PCR analysis of uterine tissue from the bitch at the time of ovariohysterectomy. PCR analysis was performed after an ovariohysterectomy of the bitch that was performed two months after parturition. Meglumine antimoniate use in the pregnant bitch may have prevented vertical transmission of leishmaniasis.

  3. The Effects of Antimony Addition on the Microstructural, Mechanical, and Thermal Properties of Sn-3.0Ag-0.5Cu Solder Alloy

    Science.gov (United States)

    Sungkhaphaitoon, Phairote; Plookphol, Thawatchai

    2018-02-01

    In this study, we investigated the effects produced by the addition of antimony (Sb) to Sn-3.0Ag-0.5Cu-based solder alloys. Our focus was the alloys' microstructural, mechanical, and thermal properties. We evaluated the effects by means of scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), differential scanning calorimetry (DSC), and a universal testing machine (UTM). The results showed that a part of the Sb was dissolved in the Sn matrix phase, and the remaining one participated in the formation of intermetallic compounds (IMCs) of Ag3(Sn,Sb) and Cu6(Sn,Sb)5. In the alloy containing the highest wt pct Sb, the added component resulted in the formation of SnSb compound and small particle pinning of Ag3(Sn,Sb) along the grain boundary of the IMCs. Our tests of the Sn-3.0Ag-0.5Cu solder alloys' mechanical properties showed that the effects produced by the addition of Sb varied as a function of the wt pct Sb content. The ultimate tensile strength (UTS) increased from 29.21 to a maximum value of 40.44 MPa, but the pct elongation (pct EL) decreased from 48.0 to a minimum 25.43 pct. Principally, the alloys containing Sb had higher UTS and lower pct EL than Sb-free solder alloys due to the strengthening effects of solid solution and second-phase dispersion. Thermal analysis showed that the alloys containing Sb had a slightly higher melting point and that the addition amount ranging from 0.5 to 3.0 wt pct Sb did not significantly change the solidus and liquidus temperatures compared with the Sb-free solder alloys. Thus, the optimal concentration of Sb in the alloys was 3.0 wt pct because the microstructure and the ultimate tensile strength of the SAC305 solder alloys were improved.

  4. Clinical and Parasitological Features of Patients with American Cutaneous Leishmaniasis that Did Not Respond to Treatment with Meglumine Antimoniate

    OpenAIRE

    Perez-Franco, Jairo E.; Cruz-Barrera, M?nica L.; Robayo, Marta L.; Lopez, Myriam C.; Daza, Carlos D.; Bedoya, Angela; Mari?o, Maria L.; Saavedra, Carlos H.; Echeverry, Maria C.

    2016-01-01

    Background American cutaneous leishmaniasis (ACL) is a complicated disease producing about 67.000 new cases per year. The severity of the disease depends on the parasite species; however in the vast majority of cases species confirmation is not feasible. WHO suggestion for ACL produced by Leishmania braziliensis, as first line treatment, are pentavalent antimonial derivatives (Glucantime or Sodium Stibogluconate) under systemic administration. According to different authors, pentavalent antim...

  5. Migration of antimony from PET bottles into beverages: determination of the activation energy of diffusion and migration modelling compared with literature data.

    Science.gov (United States)

    Welle, F; Franz, R

    2011-01-01

    Plastics bottles made from polyethylene terephthalate (PET) are increasingly used for soft drinks, mineral water, juices and beer. In this study a literature review is presented concerning antimony levels found both in PET materials as well as in foods and food simulants. On the other hand, 67 PET samples from the European bottle market were investigated for their residual antimony concentrations. A mean value of 224 ± 32 mg kg(-1) was found, the median was 220 mg kg(-1). Diffusion coefficients for antimony in PET bottle materials were experimentally determined at different temperature between 105 and 150°C. From these data, the activation energy of diffusion for antimony species from the PET bottle wall into beverages and food simulants was calculated. The obtained value of 189 kJ mol(-1) was found to be in good agreement with published data on PET microwave trays (184 kJ mol(-1)). Based on these results, the migration of antimony into beverages was predicted by mathematical migration modelling for different surface/volume ratios and antimony bottle wall concentrations. The results were compared with literature data as well as international legal limits and guidelines values for drinking water and the migration limit set from food packaging legislation. It was concluded that antimony levels in beverages due to migration from PET bottles manufactured according to the state of the art can never reach or exceed the European-specific migration limit of 40 microg kg(-1). Maximum migration levels caused by room-temperature storage even after 3 years will never be essentially higher than 2.5 microg kg(-1) and in any case will be below the European limit of 5 microg kg(-1) for drinking water. The results of this study confirm that the exposure of the consumer by antimony migration from PET bottles into beverages and even into edible oils reaches approximately 1% of the current tolerable daily intake (TDI) established by World Health Organisation (WHO). Having

  6. PANCREATIC TOXICITY AS AN ADVERSE EFFECT INDUCED BY MEGLUMINE ANTIMONIATE THERAPY IN A CLINICAL TRIAL FOR CUTANEOUS LEISHMANIASIS

    Directory of Open Access Journals (Sweden)

    Marcelo Rosandiski LYRA

    Full Text Available SUMMARY American tegumentary leishmaniasis is an infectious disease caused by a protozoan of the genus Leishmania. Pentavalent antimonials are the first choice drugs for cutaneous leishmaniasis (CL, although doses are controversial. In a clinical trial for CL we investigated the occurrence of pancreatic toxicity with different schedules of treatment with meglumine antimoniate (MA. Seventy-two patients were allocated in two different therapeutic groups: 20 or 5 mg of pentavalent antimony (Sb5+/kg/day for 20 or 30 days, respectively. Looking for adverse effects, patients were asked about abdominal pain, nausea, vomiting or anorexia in each medical visit. We performed physical examinations and collected blood to evaluate serum amylase and lipase in the pre-treatment period, and every 10 days during treatment and one month post-treatment. Hyperlipasemia occurred in 54.8% and hyperamylasemia in 19.4% patients. Patients treated with MA 20 mg Sb5+ presented a higher risk of hyperlipasemia (p = 0.023. Besides, higher MA doses were associated with a 2.05 higher risk ratio (p = 0.003 of developing more serious (moderate to severe hyperlipasemia. The attributable fraction was 51% in this group. Thirty-six patients presented abdominal pain, nausea, vomiting or anorexia but only 47.2% of those had hyperlipasemia and/ or hyperamylasemia. These findings suggest the importance of the search for less toxic therapeutic regimens for the treatment of CL.

  7. Evaluation of potential dietary toxicity of heavy metals in some common Nigerian beverages: A look at antimony, tin and mercury

    Directory of Open Access Journals (Sweden)

    I.I. Roberts

    2011-11-01

    Full Text Available There is currently little information on the composition of heavy metals in beverages imported and locally produced in Nigeria. The study quantitatively determined the composition of antimony (Sb, tin (Sn and mercury (Hg in 50 different beverage samples and evaluated the extent of violation of guideline values. Analysis of the beverage samples for the presence of Sb, Sn, and Hg was carried out using an atomic absorption spectrophotometer (AAS 929. The mean values detected for mercury, tin and antimony (±SE in fruit juices and soft drinks were 2.39±0.25, 3.66±0.22 and 0.49±0.048 μg/l; 2.93±0.34, 3.60±0.46 and 0.49±0.10 μg/l in dairy drinks and 0.94±0.02, 4.34±0.48 and 0.48±0.05 μg/l in bottled water samples respectively. While antimony detected in all products was below guideline values, mercury and tin were above the acceptable levels established by the World Health Organization, United States Environmental Protection Agency and European Union in most samples tested.

  8. Functioning of antimony film electrode in acid media under cyclic and anodic stripping voltammetry conditions.

    Science.gov (United States)

    Sebez, Bine; Ogorevc, Bozidar; Hocevar, Samo B; Veber, Marjan

    2013-06-27

    New insights into the functioning, i.e. electrochemical behaviour and analytical performance, of in situ prepared antimony film electrodes (SbFEs) under square-wave anodic stripping (SW-ASV) and cyclic (CV) voltammetry conditions are presented by studying several key operational parameters using Pb(II), Cd(II) and Zn(II) as model analyte ions. Five different carbon- and metal-based substrate transducer electrodes revealed a clear advantage of the former ones while the concentration of the precursor Sb(III) ion exhibited a distinct influence on the ASV functioning of the SbFE. Among six acids examined as potential supporting electrolytes the HNO3 was demonstrated to yield nearly identical results in conducting ASV experiments with SbFE as so far almost exclusively used HCl. This is extremely important as HNO3 is commonly employed acidifying agent in trace metal analysis, especially in elemental mass spectrometry measurements. By carrying out a systematic CV and ASV investigation using a medium exchange protocol, we confirmed the formation of poorly soluble oxidized Sb species at the substrate electrode surface at the end of each stripping step, i.e. at the potentials beyond the anodic dissolution of the antimony film. Hence, the significance of the cleaning and initializing the surface of a substrate electrode after accomplishing a stripping step was thoroughly studied in order to find conditions for a complete removal of the adhered Sb-oxides and thus to assure a memory-free functioning of the in situ prepared SbFE. Finally, the practical analytical application of the proposed ASV method was successfully tested and evaluated by measuring the three metal analytes in ground (tap) and surface (river) water samples acidified with HNO3. Our results approved the appropriateness of the SbFE and the proposed method for measuring low μg L(-1) levels of some toxic metals, particularly taking into account the possibility of on-field testing and the use of low cost

  9. Partitioning geochemistry of arsenic and antimony, El Tatio Geyser Field, Chile

    Energy Technology Data Exchange (ETDEWEB)

    Landrum, J.T. [Department of Geological Sciences, The University of Texas, Austin, TX 78759 (United States); Bennett, P.C., E-mail: pbennett@mail.utexas.edu [Department of Geological Sciences, University of Texas, Austin, TX 78759 (United States); Engel, A.S. [Department of Geology and Geophysics, Louisiana State University, Baton Rouge, LA 70803 (United States); Alsina, M.A.; Pasten, P.A. [Departamento de Ingenieria Hidraulica y Ambiental, Pontificia Universidad Catolica de Chile, Santiago (Chile); Milliken, K. [Department of Geological Sciences, University of Texas, Austin, TX 78759 (United States)

    2009-04-15

    The abundance of As and Sb in aqueous, mineral and biological reservoirs was examined at El Tatio Geyser Field, a unique hydrothermal basin located in the Atacama Desert region of Chile. Here the concentration of total As and Sb in hydrothermal springs and discharge streams are the highest reported for a natural surface water, and the geyser basin represents a significant source of toxic elements for downstream users across Region II, Chile. The geyser waters are near neutral Na:Cl type with {approx}0.45 and 0.021 mmol L{sup -1} total As and Sb, respectively, primarily in the reduced (III) redox state at the discharge with progressive oxidation downstream. The ferric oxyhydroxides associated with the microbial mats and some mineral precipitates accumulate substantial As that was identified as arsenate by XAS analysis (>10 wt% in the mats). This As is easily mobilized by anion exchange or mild dissolution of the HFO, and the ubiquitous microbial mats represent a significant reservoir of As in this system. Antimony, in contrast, is not associated with the mineral ferric oxides or the biomats, but is substantially enriched in the silica matrix of the geyserite precipitates, up to 2 wt% as Sb{sub 2}O{sub 3}. Understanding the mobility and partitioning behavior of these metalloids is critical for understanding their eventual impact on regional water management.

  10. Retardation of grain boundary self-diffusion in nickel doped with antimony and tin

    International Nuclear Information System (INIS)

    Padgett, R.A.; White, C.L.

    1984-01-01

    Many important metallurgical phenomena are strongly influenced or controlled by grain boundary mass transport. There is also much evidence that the composition of grain boundaries is often significantly different from the overall composition of metals and alloys, owing to strong segregation of residual (and often undetected) impurities. This segregation, which does not always advertise its presence through grain boundary brittleness, may vary markedly from heat to heat, and occasionally from specimen to specimen within a given heat. Unfortunately, there are relatively few experimental observations of how such segregation affects grain boundary mass transport, and even less fundamental understanding of how these effects occur. In this paper we present autoradiographic results on self-diffusion of 63 Ni in nickel and nickel doped with antimony and tin. While these results do not permit a quantitative evaluation of the grain boundary diffusivity, D, they qualitatively illustrate the dramatic effect that these solute elements have on the ability of nickel grain boundaries to act as preferential paths for mass transport

  11. Excitation functions for alpha-particle-induced reactions with natural antimony

    Energy Technology Data Exchange (ETDEWEB)

    Singh, N. L.; Shah, D. J.; Mukherjee, S.; Chintalapudi, S. N. [Vadodara, M. S. Univ. of Baroda (India). Fac. of Science. Dept. of Physics

    1997-07-01

    Stacked-foil activation technique and {gamma} - rays spectroscopy were used for the determination of the excitation functions of the {sup 121}Sb [({alpha}, n); ({alpha}, 2n); ({alpha},4 n); ({alpha}, p3n); ({alpha}, {alpha}n)]; and Sb [({alpha}, 3n); ({alpha}, 4n); ({alpha}, {alpha}3n)] reactions. The excitation functions for the production of {sup 124}I, {sup 123}I, {sup 121}I, {sup 121}Te and {sup 120}Sb were reported up to 50 MeV. The reactions {sup 121} Sb ({alpha}, {alpha}n) + {sup 123} Sb ({alpha}, {alpha}3n) are measured for the first time. Since natural antimony used as the target has two odd mass stable isotopes of abundances 57.3 % ({sup 121}Sb), their activation in some cases gives the same product nucleus through different reaction channels but with very different Q-values. In such cases, the individual reaction cross-sections are separated with the help of theoretical cross-sections. The experimental cross-sections were compared with the predictions based on hybrid model of Blann. The high-energy part of the excitation functions are dominated by the pre-equilibrium reaction mechanism and the initial exciton number n{sub 0} = 4 (4 p 0 h) gives fairly good agreement with presently measured results.

  12. Synthesis of Water-Soluble Antimony Sulfide Quantum Dots and Their Photoelectric Properties

    Science.gov (United States)

    Zhu, Jiang; Yan, Xuelian; Cheng, Jiang

    2018-01-01

    Antimony sulfide (Sb2S3) has been applied in photoelectric devices for a long time. However, there was lack of information about Sb2S3 quantum dots (QDs) because of the synthesis difficulties. To fill this vacancy, water-soluble Sb2S3 QDs were prepared by hot injection using hexadecyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) mixture as anionic-cationic surfactant, alkanol amide (DEA) as stabilizer, and ethylenediaminetetraacetic acid (EDTA) as dispersant. Photoelectric properties including absorbing and emission were characterized by UV-Vis-IR spectrophotometer and photoluminescence (PL) spectroscopic technique. An intensive PL emission at 880 nm was found, indicating Sb2S3 QDs have good prospects in near-infrared LED and near-infrared laser application. Sb2S3 QD thin films were prepared by self-assembly growth and then annealed in argon or selenium vapor. Their band gaps ( E g s) were calculated according to transmittance spectra. The E g of Sb2S3 QD thin film has been found to be tunable from 1.82 to 1.09 eV via annealing or selenylation, demonstrating the good prospects in photovoltaic application.

  13. Synthesis and evaluation of lead telluride/bismuth antimony telluride nanocomposites for thermoelectric applications

    Science.gov (United States)

    Ganguly, Shreyashi; Zhou, Chen; Morelli, Donald; Sakamoto, Jeffrey; Uher, Ctirad; Brock, Stephanie L.

    2011-12-01

    Heterogeneous nanocomposites of p-type bismuth antimony telluride (Bi 2- xSb xTe 3) with lead telluride (PbTe) nanoinclusions have been prepared by an incipient wetness impregnation approach. The Seebeck coefficient, electrical resistivity, thermal conductivity and Hall coefficient were measured from 80 to 380 K in order to investigate the influence of PbTe nanoparticles on the thermoelectric performance of nanocomposites. The Seebeck coefficients and electrical resistivities of nanocomposites decrease with increasing PbTe nanoparticle concentration due to an increased hole concentration. The lattice thermal conductivity decreases with the addition of PbTe nanoparticles but the total thermal conductivity increases due to the increased electronic thermal conductivity. We conclude that the presence of nanosized PbTe in the bulk Bi 2- xSb xTe 3 matrix results in a collateral doping effect, which dominates transport properties. This study underscores the need for immiscible systems to achieve the decreased thermal transport properties possible from nanostructuring without compromising the electronic properties.

  14. Phase diagram of antimony up to 31 GPa and 835 K

    Science.gov (United States)

    Coleman, A. L.; Stevenson, M.; McMahon, M. I.; Macleod, S. G.

    2018-04-01

    X-ray powder diffraction experiments using resistively heated diamond anvil cells have been conducted in order to establish the phase behavior of antimony up to 31 GPa and 835 K. The dip in the melting curve at 5.7 GPa and 840 K is identified as the triple point between the Sb-I, incommensurate Sb-II, and liquid phases. No evidence of the previously reported simple cubic phase was observed. Determination of the phase boundary between Sb-II and Sb-III suggests the existence of a second triple point in the region of 13 GPa and 1200 K. The incommensurate composite structure of Sb-II was found to remain ordered to the highest temperatures studies—no evidence of disordering of the guest-atom chains was observed. Indeed, the modulation reflections that arise from interactions between the host and guest subsystems were found to be present to the highest temperatures, suggesting such interactions remain relatively strong in Sb even in the presence of increased thermal motion. Finally, we show that the incommensurately modulated structure recently reported as giving an improved fit to diffraction data from incommensurate Ba-IV can be rejected as the structure of Sb-II using a simple density argument.

  15. Synthesis of Copper-Antimony-Sulfide Nanocrystals for Solution-Processed Solar Cells.

    Science.gov (United States)

    Suehiro, Satoshi; Horita, Keisuke; Yuasa, Masayoshi; Tanaka, Tooru; Fujita, Katsuhiko; Ishiwata, Yoichi; Shimanoe, Kengo; Kida, Tetsuya

    2015-08-17

    The p-type nanocrystals (NCs) of copper-based chalcogenides, such as CuInSe2 and Cu2ZnSnS4, have attracted increasing attention in photovoltaic applications due to their potential to produce cheap solution-processed solar cells. Herein, we report the synthesis of copper-antimony-sulfide (CAS) NCs with different crystal phases including CuSbS2, Cu3SbS4, and Cu12Sb4S13. In addition, their morphology, crystal phase, and optical properties were characterized using transmission electron microscopy, X-ray diffractometry, UV-vis-near-IR spectroscopy, and photoemission yield spectroscopy. The morphology, crystal phase, and electronic structure were significantly dependent on the chemical composition in the CAS system. Devices were fabricated using particulate films consisting of CAS NCs prepared by spin coating without a high-temperature treatment. The CAS NC-based devices exhibited a diode-like current-voltage characteristic when coupled with an n-type CdS layer. In particular, the CuSbS2 NC devices exhibited photovoltaic responses under simulated sunlight, demonstrating its applicability for use in solution-processed solar cells.

  16. Determination of antimony by using a quartz atom trap and electrochemical hydride generation atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Menemenlioglu, Ipek; Korkmaz, Deniz [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey); Ataman, O. Yavuz [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey)], E-mail: ataman@metu.edu.tr

    2007-01-15

    The analytical performance of a miniature quartz trap coupled with electrochemical hydride generator for antimony determination is described. A portion of the inlet arm of the conventional quartz tube atomizer was used as an integrated trap medium for on-line preconcentration of electrochemically generated hydrides. This configuration minimizes transfer lines and connections. A thin-layer of electrochemical flow through cell was constructed. Lead and platinum foils were employed as cathode and anode materials, respectively. Experimental operation conditions for hydride generation as well as the collection and revolatilization conditions for the generated hydrides in the inlet arm of the quartz tube atomizer were optimized. Interferences of copper, nickel, iron, cobalt, arsenic, selenium, lead and tin were examined both with and without the trap. 3{sigma} limit of detection was estimated as 0.053 {mu}g l{sup -1} for a sample size of 6.0 ml collected in 120 s. The trap has provided 18 fold sensitivity improvement as compared to electrochemical hydride generation alone. The accuracy of the proposed technique was evaluated with two standard reference materials; Trace Metals in Drinking Water, Cat CRM-TMDW and Metals on Soil/Sediment 4, IRM-008.

  17. Determination of antimony by using a quartz atom trap and electrochemical hydride generation atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Menemenlioglu, Ipek; Korkmaz, Deniz; Ataman, O. Yavuz

    2007-01-01

    The analytical performance of a miniature quartz trap coupled with electrochemical hydride generator for antimony determination is described. A portion of the inlet arm of the conventional quartz tube atomizer was used as an integrated trap medium for on-line preconcentration of electrochemically generated hydrides. This configuration minimizes transfer lines and connections. A thin-layer of electrochemical flow through cell was constructed. Lead and platinum foils were employed as cathode and anode materials, respectively. Experimental operation conditions for hydride generation as well as the collection and revolatilization conditions for the generated hydrides in the inlet arm of the quartz tube atomizer were optimized. Interferences of copper, nickel, iron, cobalt, arsenic, selenium, lead and tin were examined both with and without the trap. 3σ limit of detection was estimated as 0.053 μg l -1 for a sample size of 6.0 ml collected in 120 s. The trap has provided 18 fold sensitivity improvement as compared to electrochemical hydride generation alone. The accuracy of the proposed technique was evaluated with two standard reference materials; Trace Metals in Drinking Water, Cat CRM-TMDW and Metals on Soil/Sediment 4, IRM-008

  18. 90Y-labeled antimony trisulfide colloid as promising therapeutic agent: Physicochemical characterization and biological evaluation

    Directory of Open Access Journals (Sweden)

    Janković Drina Lj.

    2014-01-01

    Full Text Available Introduction The suitability of 90Y-labeled antimony trisulfide colloid (ATC for the preparation of therapeutic radiopharmaceutical was studied taking into accounts its physicochemical properties and biological behavior in rats. Material and methods The labeling efficiency of 90Y- and 99mTc-labeled colloid particles was investigated by ITLC-SG and paper chromatography, the in vitro stability of the colloid was tested in human serum, while in vivo experiments were performed on healthy Wistar rats. Analysis of the particles enclosed the size (TEM, determination of the zeta potential (Zetasizer Nano as well as radioactivity particle size distribution (filtration analysis. Results 90Y-labeled ATC can be prepared in high yield under investigated conditions Labeling efficiency was >95% and filtration analysis showed that more than 90% of radioactive particles were smaller than 20 nm. The particles with the size range of 6-22 nm were achieved by using polyvinyipyrrolidone (mol wt ~44,000. The 90Y-ATC was quite stable in vitro in human serum. Tissue distribution studies in rats confirmed that the liver and spleen uptake of 90Y-labeled colloid was three-fold lower in comparison with 99mTc-ATC, although the bone uptake was five-fold higher at 20 min post injection. Conclusions 90Y-labeled ATC showed high labeling efficiency and good stability, and might be well suited for therapeutic application in nuclear medicine.

  19. Carbon nanotubes modified with antimony nanoparticles: A novel material for electrochemical sensing

    International Nuclear Information System (INIS)

    Moraes, Fernando C.; Cesarino, Ivana; Cesarino, Vivian; Mascaro, Lucia H.; Machado, Sergio A.S.

    2012-01-01

    Highlights: ► A novel material for the electrochemical sensing was developed. ► Sensor based CNTs modified with Sb-nanoparticles was characterised and applied. ► The proposed sensor was suitable and sensitive for the determination of bisphenol A. - Abstract: In this study, a novel material for the electrochemical determination of bisphenol A using a nanocomposite based on multi-walled carbon nanotubes modified with antimony nanoparticles has been investigated. The morphology, structure, and electrochemical performance of the nanocomposite electrodes were characterised by field emission gun scanning electron microscopy, energy-dispersive X-ray spectroscopy, and cyclic voltammetry. A scan rate study and electrochemical impedance spectroscopy showed that the bisphenol A oxidation product is adsorbed on nanocomposite electrode surface. Differential pulse voltammetry in phosphate buffer solution at pH 6, allowed the development of a method to determine bisphenol A levels in the range of 0.5–5.0 μmol L −1 , with a detection limit of 5.24 nmol L −1 (1.19 μg L −1 ).

  20. Leaching of Antimony (Sb)from Municipal Solid Waste Incineration (MSWI) Residues

    Energy Technology Data Exchange (ETDEWEB)

    Herrmann, Inga

    2004-07-01

    The mobility of antimony (Sb) in municipal solid waste incineration (MSWI) residues often exceeds the limit values stipulated by the European Union. As an ash treatment by washing is conceivable, this work investigated the Sb release from Swedish bottom ash and fly ash when mixed with water. The leaching experiments revealed the factors significantly (a = 0.05) affecting Sb release from the ashes. The following factors were investigated: Liquid to solid ratio (L/S), time, pH, carbonation (treatment with CO{sub 2}), ultrasonics and temperature. The data were evaluated using multiple linear regression (MLR). The impact of the factors could be quantified. The maximum Sb release calculated was 13 mg/kg DM for bottom ash and 51 mg/kg DM for fly ash. The derived models explained the observed data well. Nevertheless, the calculated values were subject to a high uncertainty. For bottom ash, a lowering of the Sb total content of approximately 22% could be achieved. If this also involves a sufficient lowering of the Sb mobility to meet EU limit values could not yet be assessed. Chemical equilibrium calculations were performed to explain the empirical results. However, no solid phases controlling Sb release from the ashes could be identified.

  1. Capacity extended bismuth-antimony cathode for high-performance liquid metal battery

    Science.gov (United States)

    Dai, Tao; Zhao, Yue; Ning, Xiao-Hui; Lakshmi Narayan, R.; Li, Ju; Shan, Zhi-wei

    2018-03-01

    Li-Bi based liquid metal batteries (LMBs) have attracted interest due to their potential for solving grid scale energy storage problems. In this study, the feasibility of replacing the bismuth cathode with a bismuth-antimony alloy cathode in lithium based LMBs is investigated. The influence of the Bi:Sb ratio on voltage characteristics is evaluated via the constant current discharge method and electrochemical titration. On observing the cross section of the electrode at various stages of discharge, it is determined that both Sb and Bi form solid intermetallics with Li on the cathode. Additionally, the addition of Bi not only reduces the melting temperature of the Bi:Sb intermetallic but also actively contributes to the electrode capacity. Thereafter, a Li|LiCl-LiF|Sb-Bi liquid metal battery with 3 A h nameplate capacity, assembled and cycled at 1 C rate, is found to possess a stable capacity for over 160 cycles. The overall performance of this battery is discussed in the context of cost effectiveness, energy and coulombic efficiencies.

  2. Effects of antimony trisulfide (Sb2S3) on sliding friction of automotive brake friction materials

    Science.gov (United States)

    Lee, Wan Kyu; Rhee, Tae Hee; Kim, Hyun Seong; Jang, Ho

    2013-09-01

    The effect of antimony trisulfide (Sb2S3) on the tribological properties of automotive brake friction materials was investigated using a Krauss type tribometer and a 1/5 scale dynamometer with a rigid caliper. Results showed that Sb2S3 improved fade resistance by developing transfer films on the disc surface at elevated temperatures. On the other hand, the rubbing surfaces of the friction material exhibited contact plateaus with a broader height distribution when it contained Sb2S3, indicating fewer contact junctions compared to the friction material with graphite. The friction material with Sb2S3 also exhibited a lower stick-slip propensity than the friction material with graphite. The improved fade resistance with Sb2S3 is attributed to its lubricating capability sustained at high temperatures, while the lower stick-slip propensity of the friction material with Sb2S3 is associated with the slight difference between its static and kinetic coefficients of friction and high normal stiffness.

  3. Assessment and distribution of antimony in soils around three coal mines, Anhui, China

    Science.gov (United States)

    Qi, C.; Liu, Gaisheng; Kang, Y.; Lam, P.K.S.; Chou, C.

    2011-01-01

    Thirty-three soil samples were collected from the Luling, Liuer, and Zhangji coal mines in the Huaibei and Huainan areas of Anhui Province, China. The samples were analyzed for antimony (Sb) by inductively coupled plasmaoptical emission spectrometry (ICP-OES) method. The average Sb content in the 33 samples was 4 mg kg-1, which is lower than in coals from this region (6.2 mg kg-1). More than 75% of the soils sampled showed a significant degree of Sb pollution (enrichment factors [EFs] 5-20). The soils collected near the gob pile and coal preparation plant were higher in Sb content than those collected from residential areas near the mines. The gob pile and tailings from the preparation plant were high in mineral matter content and high in Sb. They are the sources of Sb pollution in surface soils in the vicinity of coal mines. The spatial dispersion of Sb in surface soil in the mine region shows that Sb pollution could reach out as far as 350 m into the local environment conditions. Crops in rice paddies may adsorb some Sb and reduce the Sb content in soils from paddyfields. Vertical distribution of Sb in two soil profiles indicates that Sb is normally relatively immobile in soils. ?? 2011 Air & Waste Management Association.

  4. Adsorption of Antimony by Bagasse Fly Ash: Chemical Modification and Adsorption Mechanism.

    Science.gov (United States)

    Leechart, Piyawan; Inthorn, Duangrat; Thiravetyan, Paitip

      Modification of bagasse fly ash (BFA) and the adsorption mechanism of antimony (Sb) by modified BFA were studied. It was found that BFA grafted with acrylic acid (BFAG) and BFA treated with hydrochloric acid (BFA/HCl) led to a decrease in the pH of the zero point of charge (pH zpc ) of the adsorbents. The pH zpc of BFA, BFAG, BFA/HCl and activated carbon (AC) were 8.3, 6.4, 6.2 and 8.2, respectively. The maximum adsorption capacities (Q max ) of Sb by BFA, BFAG, BFA/HCl and AC were 0.14, 0.34, 0.38 and 0.29 mg Sb/g adsorbent, respectively. Modified BFA had Q max higher than AC although the BET surface area of AC was the highest. This was due to the system pH of BFAG and BFA/HCl was 5.20-6.00 and the pH zpc of BFAG and BFA/HCl accounted for 6.4 and 6.2, respectively. Therefore, the adsorbent surface had a positive charge, resulting in increasing adsorption of Sb.

  5. Speciation of very low amounts of antimony in waters using magnetic core-modified silver nanoparticles and electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    López-García, Ignacio; Rengevicova, Silvia; Muñoz-Sandoval, María J; Hernández-Córdoba, Manuel

    2017-01-01

    A micro-solid phase extraction procedure for the separation and preconcentration of antimony based in the use of magnetic particles covered with silver nanoparticles functionalized with the sodium salt of 2-mercaptoethane-sulphonate (MESNa) is discussed. After separation by means of a magnetic field, the solid phase is directly introduced into an electrothermal atomizer for antimony determination. Alternatively, the solid can be slurried and then injected into the atomizer. In all cases, palladium nitrate is used as a chemical modifier. The preconcentration factors are close to 205 and 325, with detection limits of 0.02 and 0.03µgL -1 antimony, for the slurry and solid sampling procedures, respectively. Speciation of Sb(III) and Sb(V) is achieved by means of two extractions carried out at different acidity. The results for total antimony are verified using certified reference materials. Water samples are analyzed for antimony speciation. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Failure of both azithromycin and antimony to treat cutaneous leishmaniasis in Manaus, AM, Brazil Falha da azitromicina e do antimonial no tratamento da leishmaniose cutânea em Manaus, AM, Brasil

    Directory of Open Access Journals (Sweden)

    Alan César Teixeira

    2008-06-01

    Full Text Available A non-randomized controlled clinical trial was carried outin order to evaluate both azithromycin and antimony efficacy in cutaneous leishmaniasis in Manaus, AM, Brazil. Forty nine patients from both genders, aged 14 to 70, with cutaneous ulcers for less than three months and a positive imprint for Leishmania spp. amastigotes were recruited into two groups. Group I (26 patients received a daily-single oral dose of 500 mg of azithromycin for 20 days and Group II (23 patients received a daily-single intramuscular dose of 20 mg/kg of meglumine antimony, also for 20 days. Azithromycin cured three of 24 (12.5% patients on days 60, 90 and 120 respectively whereas therapeutic failure was considered in 21 of 24 (87.5% cases. In group II, antimony cured eight of 19 (42.1% cases as follows: three on day 30, one each on day 60 and day 90, and three on day 120. Therapeutic failure occurred in 11 of 19 (57.9% individuals. The efficacy of antimony for leishmaniasis was better than azithromycin but analysis for the intention-to-treat response rate did not show statistical difference between them. Although azithromycin was better tolerated, it showed a very low efficacy to treat cutaneous leishmaniasis in Manaus.Com o objetivo de avaliar a eficácia da azitromicina no tratamento da leishmaniose cutânea, foi realizado ensaio comparativo, em Manaus. Foram recrutados 49 pacientes de ambos os sexos, com idades entre 14 e 70 anos que apresentassem úlceras cutâneas com menos de três meses de evolução e que tivessem exame direto positivo para amastigotas de leishmânia. Estes pacientes foram alocados em dois grupos assim: Grupo I (26 recebeu uma dose diária de 500 mg de azitromicina pela via oral durante 20 dias e o Grupo II, recebeu uma dose diária de 20 mg/kg de antimoniato de meglumina por via intramuscular, durante 20 dias. Do grupo da azitromicina, três (12,5% de 24 pacientes curaram 60, 90 e 120 dias, respectivamente, enquanto, em 21 (87,5% de 24 houve

  7. Comparison of modification with strontium and the refining with antimony in A 356 aluminium alloys; Comparacao entre a modificacao com estroncio e o refino com antimonio em ligas de aluminio a 356

    Energy Technology Data Exchange (ETDEWEB)

    Fuoco, Ricardo; Correa, Edison Roberto; Correa, Alzira V.O.; Bocalini Junior, Mario

    1992-12-31

    Strontium and Antimony treated A356 aluminium alloy samples were metallographically characterized in the as cast and solution and aged conditions. Antimony treated alloy has shown slower spheroidizing kinetics of the Silicon particles during solution treatment, lower porosity level and higher tensile strength and elongation than Strontium treated one. (author) 26 refs., 13 figs., 2 tabs.

  8. Changes induced by gamma radiation in nanocomposites based on copper II and antimony sulfides in commercial poly(methyl methacrylate) matrix

    International Nuclear Information System (INIS)

    Albuquerque, M.C.C. de; Garcia, O.P.; Aquino, K.A.S.; Araujo, E.S.

    2010-01-01

    Poly (methyl methacrylate) (PMMA) is a polymer with wide application in the manufacture of medical devices that is exposed to gamma irradiation. Currently the use of composite materials has been disseminated and PMMA is an excellent polymer matrix to package various materials. This study aimed to analyze the changes induced by gamma irradiation (25 kGy) on the properties of PMMA nanocomposites with nanoparticles of copper II sulfide (250nm-900nm) and antimony sulfite (300-500 nm). The nanoparticles were added to the polymer in different concentrations and synthesized by ultrasonic irradiation from the corresponding chlorides with thioacetamide. Viscometric results showed a good radioprotective effect of nanoparticles of copper and antimony. It was found a good protection of nanoparticles on PMMA matrix in the concentration of 0.3% wt. The protections of 75% and 50% were calculated for nanoparticles of antimony and copper II, respectively. (author)

  9. Clinical and Parasitological Features of Patients with American Cutaneous Leishmaniasis that Did Not Respond to Treatment with Meglumine Antimoniate.

    Directory of Open Access Journals (Sweden)

    Jairo E Perez-Franco

    2016-05-01

    Full Text Available American cutaneous leishmaniasis (ACL is a complicated disease producing about 67.000 new cases per year. The severity of the disease depends on the parasite species; however in the vast majority of cases species confirmation is not feasible. WHO suggestion for ACL produced by Leishmania braziliensis, as first line treatment, are pentavalent antimonial derivatives (Glucantime or Sodium Stibogluconate under systemic administration. According to different authors, pentavalent antimonial derivatives as treatment for ACL show a healing rate of about 75% and reasons for treatment failure are not well known.In order to characterise the clinical and parasitological features of patients with ACL that did not respond to Glucantime, a cross-sectional observational study was carried out in a cohort of 43 patients recruited in three of the Colombian Army National reference centers for complicated ACL. Clinical and paraclinical examination, and epidemiological and geographic information were recorded for each patient. Parasitological, histopathological and PCR infection confirmation were performed. Glucantime IC50 and in vitro infectivity for the isolated parasites were estimated.Predominant infecting Leishmania species corresponds to L. braziliensis (95.4% and 35% of the parasites isolated showed a significant decrease in in vitro Glucanatime susceptibility associated with previous administration of the medicament. Lesion size and in vitro infectivity of the parasite are negatively correlated with decline in Glucantime susceptibility (Spearman: r = (-0,548 and r = (-0,726; respectively.A negative correlation between lesion size and parasite resistance is documented. L. braziliensis was found as the main parasite species associated to lesion of patients that underwent treatment failure or relapse. The indication of a second round of treatment in therapeutic failure of ACL, produced by L. braziliensis, with pentavalent antimonial derivatives is discussable.

  10. First-line therapy for human cutaneous leishmaniasis in Peru using the TLR7 agonist imiquimod in combination with pentavalent antimony.

    Directory of Open Access Journals (Sweden)

    Cesar Miranda-Verastegui

    2009-07-01

    Full Text Available Current therapies for cutaneous leishmaniasis are limited by poor efficacy, long-term course of treatment, and the development of resistance. We evaluated if pentavalent antimony (an anti-parasitic drug combined with imiquimod (an immunomodulator was more effective than pentavalent antimony alone in patients who had not previously been treated.A randomized double-blind clinical trial involving 80 cutaneous leishmaniasis patients was conducted in Peru. The study subjects were recruited in Lima and Cusco (20 experimental and 20 control subjects at each site. Experimental arm: Standard dose of pentavalent antimony plus 5% imiquimod cream applied to each lesion three times per week for 20 days. Control arm: Standard dose of pentavalent antimony plus placebo (vehicle cream applied as above. The primary outcome was cure defined as complete re-epithelization with no inflammation assessed during the 12 months post-treatment period.Of the 80 subjects enrolled, 75 completed the study. The overall cure rate at the 12-month follow-up for the intention-to-treat analysis was 75% (30/40 in the experimental arm and 58% (23/40 in the control arm (p = 0.098. Subgroup analyses suggested that combination treatment benefits were most often observed at the Cusco site, where L. braziliensis is the prevalent species. Over the study period, only one adverse event (rash was recorded, in the experimental arm.The combination treatment of imiquimod plus pentavalent antimony performed better than placebo plus pentavalent antimony, but the difference was not statistically significant.Clinical Trials.gov NCT00257530.

  11. Synthesis and evaluation of lead telluride/bismuth antimony telluride nanocomposites for thermoelectric applications

    International Nuclear Information System (INIS)

    Ganguly, Shreyashi; Zhou Chen; Morelli, Donald; Sakamoto, Jeffrey; Uher, Ctirad; Brock, Stephanie L.

    2011-01-01

    Heterogeneous nanocomposites of p-type bismuth antimony telluride (Bi 2−x Sb x Te 3 ) with lead telluride (PbTe) nanoinclusions have been prepared by an incipient wetness impregnation approach. The Seebeck coefficient, electrical resistivity, thermal conductivity and Hall coefficient were measured from 80 to 380 K in order to investigate the influence of PbTe nanoparticles on the thermoelectric performance of nanocomposites. The Seebeck coefficients and electrical resistivities of nanocomposites decrease with increasing PbTe nanoparticle concentration due to an increased hole concentration. The lattice thermal conductivity decreases with the addition of PbTe nanoparticles but the total thermal conductivity increases due to the increased electronic thermal conductivity. We conclude that the presence of nanosized PbTe in the bulk Bi 2−x Sb x Te 3 matrix results in a collateral doping effect, which dominates transport properties. This study underscores the need for immiscible systems to achieve the decreased thermal transport properties possible from nanostructuring without compromising the electronic properties. - Graphical abstract: PbTe nanoparticles introduced into p-type Bi 2 Te 3 by incipient wetness results in decreased lattice thermal conductivity, but also acts as an electronic dopant, resulting in an overall decrease in thermoelectric performance. Highlights: ► Composites of PbTe nanoparticles in Bi 2−x Sb x Te 3 were formed by incipient wetness. ► PbTe nanoparticles leads to decreased κ l , consistent with phonon scattering. ► PbTe nanoparticles lead to decreased S and ρ, due to increased carriers. ► Collateral doping from PbTe leads to decreased ZT with increasing concentration. ► Immiscible systems are preferred for improved ZT.

  12. Antimony and arsenic leaching from secondary lead smelter air-pollution-control residues.

    Science.gov (United States)

    Ettler, Vojtech; Mihaljevic, Martin; Sebek, Ondrej

    2010-07-01

    Environments in the vicinity of the lead (Pb) smelters are contaminated by emissions containing high concentrations of antimony (Sb) and arsenic (As). Air-pollution-control (APC) residues from bag-type filters from a secondary Pb smelter were subjected to leaching experiments to elucidate the controlling mechanisms of Sb and As release. Kinetic batch leaching tests at a liquid-to-solid (L/S) ratio of 10 L kg(- 1) within the time frame of 720 hours and batch leaching at various L/S ratios (ranging from 1 to 1000 L kg(-1)) were performed. In contrast to other inorganic contaminants (Pb, Cd, Zn), less than 1% of the total Sb and As content was leached from the residues. At a L/S ratio of 10, the As and Sb concentrations in the leachates exceeded the EU limit values for non-hazardous waste (0.2 and 0.07 mg L(-1) ). According to PHREEQC-2 calculations, the concentrations of As and Sb are controlled by the precipitation of complex arsenates and antimonates mainly at low L/S ratios. The washing and related chemical/mineralogical transformation of APC residues was suggested as a technological pre-treatment process before their re-smelting in a blast furnace. The Ferrox-like processing of the resulting contaminated process water/leachate was simulated using the PHREEQC-2 code. Significant reduction was obtained in the concentration of some key contaminants (As, Cu, Pb, Zn) related to sorption on newly formed hydrous ferric oxides, whereas Sb and Cd exhibited only limited attenuation.

  13. Deposition efficiency in the preparation of ozone-producing nickel and antimony doped tin oxide anodes

    Directory of Open Access Journals (Sweden)

    Staffan Sandin

    2017-03-01

    Full Text Available The influence of precursor salts in the synthesis of nickel and antimony doped tin oxide (NATO electrodes using thermal decomposition from dissolved chloride salts was investigated. The salts investigated were SnCl4×5H2O, SnCl2×2H2O, SbCl3 and NiCl2×6H2O. It was shown that the use of SnCl4×5H20 in the preparation process leads to a tin loss of more than 85 %. The loss of Sb can be as high as 90 % while no indications of Ni loss was observed. As a consequence, the concentration of Ni in the NATO coating will be much higher than in the precursor solution. This high and uncontrolled loss of precursors during the preparation process will lead to an unpredictable composition in the NATO coating and will have negative economic and environmental effects. It was found that using SnCl2×2H20 instead of SnCl4×5H2O can reduce the tin loss to less than 50 %. This tin loss occurs at higher temperatures than when using SnCl4×5H2O where the tin loss occurs from 56 – 147 °C causing the composition to change both during the drying (80 – 110 °C and calcination (460 -550 °C steps of the preparation process. Electrodes coated with NATO based on the two different tin salts were investigated for morphology, composition, structure, and ozone electrocatalytic properties.

  14. Intralesional Infiltration with Meglumine Antimoniate for the Treatment of Leishmaniasis Recidiva Cutis in Ecuador.

    Science.gov (United States)

    Calvopiña, Manuel; Cevallos, William; Paredes, Yolanda; Puebla, Edison; Flores, Jessica; Loor, Richard; Padilla, José

    2017-11-01

    Meglumine Antimoniate (MA), administered intramuscularly for 21 continuous days is the recommended treatment of leishmaniases in Ecuador. However, because of its toxicity and requirement for intramuscular injections, treatment is frequently abandoned before completion. In addition, therapeutic failure and reactivation are not uncommon. Here we evaluate the efficacy and safety of MA administered intralesionally (IL) in leishmaniasis recidiva cutis (LRC). LRC is a special clinical variant of cutaneous leishmaniasis, characterized by reactivation at the edges of a primary cured lesion, presenting with active papules around the scar. Twenty-one patients were included in the study. All were diagnosed parasitologically by one of three diagnostic methods (smear, culture, and Leishmanin skin test). Each patient received MA intralesionally weekly for 4 weeks. Each papule was infiltrated until complete saturation. On average, patients received 1 mL of MA per administration. The criterion of cure was the complete resolution of the papules. Follow up was performed at 30, 90, and 180 days after treatment. At day 30 after treatment, 19 (90.5%) of 21 patients were clinically cured. The two patients, who did not heal by the fourth application, were cured on the seventh and eighth dose, achieving a clinical cure of 100% without subsequent reactivation. Mild to moderate local pain during infiltration was the only adverse reaction experienced by 81% of patients. In one case, subsequent infiltrations were discontinued because of a local allergic reaction. Complete compliance of patients to treatment and the small volume of drug administered make this method of administering MA an effective, safe, and inexpensive alternative. Consequently, IL could replace intramuscular administration in the treatment of LRC in Ecuador.

  15. TiO(2) crystal facet-dependent antimony adsorption and photocatalytic oxidation.

    Science.gov (United States)

    Song, Jiaying; Yan, Li; Duan, Jinming; Jing, Chuanyong

    2017-06-15

    Anatase TiO 2 crystal facets are garnering increasing attention due to their unique surface property. However, no specific linear relationship had been derived between the facet exposed on TiO 2 and the surface adsorption capacity as well as photocatalytic performance. This study systematically explored the facet effects on antimony (Sb) adsorption and photocatalytic oxidation using high-index {201} and low-index {101}, {001}, and {100} TiO 2 . The results suggest that high-index {201} TiO 2 exhibits the best Sb(III) adsorption and photocatalytic activity compared to the low-index TiO 2 . Both the Sb(III) adsorption density and the amount of OH and O 2 - generated in solution were correlated to the magnitude of surface energy on TiO 2 facets. Photocatalytically generated OH and O 2 - were responsible for Sb(III) photooxidation as evidenced by radical-trapping experiments. The great contribution of OH was observed only on {201}, not on low-index TiO 2 . This phenomenon was found to be attributable to the high surface energy on {201}, which enables the generation of a large amount of photogeneration OH to compensate for the fast rate of OH dissipation. Therefore, the predominant participation of OH in Sb(III) photooxidation was only possible on high-index {201} TiO 2 , which resulted in an enhanced photocatalytic rate. On the other hand, O 2 - dominated the Sb(III) photocatalytic oxidation on low-index TiO 2 . The intrinsic facet-dependent adsorption and photocatalytic mechanism obtained from this study would be useful for developing TiO 2 -based environmental technologies. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Photochemical properties of mono-, tri-, and penta-cationic antimony(V) metalloporphyrin derivatives on a clay layer surface.

    Science.gov (United States)

    Tsukamoto, Takamasa; Shimada, Tetsuya; Takagi, Shinsuke

    2013-08-22

    Three types of mono-, tri-, and penta-cationic antimony(V) porphyrin derivatives (Sb(V)Pors) were synthesized, and their photochemical properties on the anionic clay were systematically investigated. Sb(V)Por derivatives are dihydroxo(5,10,15,20-tetraphenylporphyrinato)antimony(V) chloride ([Sb(V)(TPP)(OH)2](+)Cl(-)), dihydroxo[5,10-diphenyl-15,20-di(N-methyl-pyridinium-4-yl)porphyrinato]antimony(V) trichloride ([Sb(V)(DMPyP)(OH)2](3+)3Cl(-)), and dihydroxo[5,10,15,20-tetrakis(N-methyl-pyridinium-4-yl)porphyrinato]antimony(V) pentachloride ([Sb(V)(TMPyP)(OH)2](5+)5Cl(-)). The photochemical behaviors of three cationic Sb(V)Pors with and without clay were examined in aqueous solution. For all Sb(V)Por, aggregation behaviors were not observed in the clay complexes even at high density adsorption conditions. The transition probabilities and fluorescence quantum yields of Sb(V)Por showed a tendency to be increased by the complex formation with clay. The less cationic Sb(V)Por/clay complex showed the larger fluorescence quantum yield. The more cationic Sb(V)Por/clay complex showed the longer fluorescence lifetime. These effects of complex formation with clay on the photochemical properties of Sb(V)Pors were discussed using the molecular potential energy curves of the porphyrin ground state and excited state. It is concluded that two types of effects work in the Sb(V)Por/clay system: effect i (structure resembling effect) is that the most stable structure becomes relatively similar between the ground and excited states, mainly by hydrophobic interactions between the porphyrin molecule and the clay surface, and effect ii (structure fixing effect) is that sharpened potential energy curves of clay complexes can lead to the increase of activation energy for the internal conversion from excited state to a high vibration level of ground state, mainly by electrostatic interactions between cationic porphyrin and anionic clay. Like this, the unique effects of the clay surface on

  17. Influence of zirconium ions on the uptake of carrier-free antimony (III) (125Sb) by various sorbents

    International Nuclear Information System (INIS)

    Friedmann, Ch.; Schoenfeld, T.; Vienna Univ.

    1975-01-01

    Sorption of carrier-free radioantimony ( 125 Sb) from acid aqueous solutions is strongly influenced by the presence of zirconium. For some sorbents (diatomaceous earth, clay minerals, activated charcoal) small amounts of dissolved zirconium salts increase 125 Sb sorption strongly. Larger amounts of zirconium reduce sorption again, sometimes below the uptake occurring in the absence of zirconium. With aluminium oxide only a reduction in uptake of 125 Sb results from the presence of Zr. These effects can be attributed to the formation of soluble complex species of zirconium with antimony (polynuclear cohydrolysis products) and to their sorption behaviour. (F.G.)

  18. Multipurpose Compound

    Science.gov (United States)

    1983-01-01

    Specially formulated derivatives of an unusual basic compound known as Alcide may be the answer to effective treatment and prevention of the disease bovine mastitis, a bacterial inflammation of a cow's mammary gland that results in loss of milk production and in extreme cases, death. Manufactured by Alcide Corporation the Alcide compound has killed all tested bacteria, virus and fungi, shortly after contact, with minimal toxic effects on humans or animals. Alcide Corporation credits the existence of the mastitis treatment/prevention products to assistance provided the company by NERAC, Inc.

  19. Mesoionic Compounds

    Indian Academy of Sciences (India)

    Sydnone, the representative mesoionic compound has been extensively studied because of its unusual structure, chemi- cal properties and synthetic utility. Sydnone is used as a versatile synthon in heterocyclic synthesis. This article gives a brief account of the comparative studies of the structural features of mesoionic ...

  20. Nutritional status in patients with cutaneous leishmaniasis and a study of the effects of zinc supplementation together with antimony treatment

    Directory of Open Access Journals (Sweden)

    Miguel Guzman-Rivero

    2014-11-01

    Full Text Available Background: The role of micronutrient status for the incidence and clinical course of cutaneous leishmaniasis is not much studied. Still zinc supplementation in leishmaniasis has shown some effect on the clinical recovery, but the evidence in humans is limited. Objective: To compare biochemical nutritional status in cutaneous leishmaniasis patients with that in controls and to study the effects of zinc supplementation for 60 days. Design: Twenty-nine patients with cutaneous leishmaniasis were treated with antimony for 20 days. Fourteen of them got 45 mg zinc daily and 15 of them got placebo. Biomarkers of nutritional and inflammatory status and changes in size and characteristics of skin lesions were measured. Results: The level of transferrin receptor was higher in patients than in controls but otherwise no differences in nutritional status were found between patients and controls. No significant effects of zinc supplementation on the clinical recovery were observed as assessed by lesion area reduction and characteristics or on biochemical parameters. Conclusions: It is concluded that nutritional status was essentially unaffected in cutaneous leishmaniasis and that oral zinc supplementation administered together with intramuscular injection of antimony had no additional clinical benefit.

  1. Antimony Anchored with Nitrogen-Doping Porous Carbon as a High-Performance Anode Material for Na-Ion Batteries.

    Science.gov (United States)

    Wu, Tianjing; Hou, Hongshuai; Zhang, Chenyang; Ge, Peng; Huang, Zhaodong; Jing, Mingjun; Qiu, Xiaoqing; Ji, Xiaobo

    2017-08-09

    Antimony represents a class of unique functional materials in sodium-ion batteries with high theoretical capacity (660 mA h g -1 ). The utilization of carbonaceous materials as a buffer layer has been considered an effective approach to alleviate rapid capacity fading. Herein, the antimony/nitrogen-doping porous carbon (Sb/NPC) composite with polyaniline nanosheets as a carbon source has been successfully achieved. In addition, our strategy involves three processes, a tunable organic polyreaction, a thermal annealing process, and a cost-effective reduction reaction. The as-prepared Sb/NPC electrode demonstrates a great reversible capacity of 529.6 mA h g -1 and an outstanding cycling stability with 97.2% capacity retention after 100 cycles at 100 mA g -1 . Even at 1600 mA g -1 , a superior rate capacity of 357 mA h g -1 can be retained. Those remarkable electrochemical performances can be ascribed to the introduction of a hierarchical porous NPC material to which tiny Sb nanoparticles of about 30 nm were well-wrapped to buffer volume expansion and improve conductivity.

  2. Treatment of air pollution control residues with iron rich waste sulfuric acid: does it work for antimony (Sb)?

    Science.gov (United States)

    Okkenhaug, Gudny; Breedveld, Gijs D; Kirkeng, Terje; Lægreid, Marit; Mæhlum, Trond; Mulder, Jan

    2013-03-15

    Antimony (Sb) in air pollution control (APC) residues from municipal solid waste incineration has gained increased focus due to strict Sb leaching limits set by the EU landfill directive. Here we study the chemical speciation and solubility of Sb at the APC treatment facility NOAH Langøya (Norway), where iron (Fe)-rich sulfuric acid (∼3.6M, 2.3% Fe(II)), a waste product from the industrial extraction of ilmenite, is used for neutralization. Antimony in water extracts of untreated APC residues occurred exclusively as pentavalent antimonate, even at low pH and Eh values. The Sb solubility increased substantially at pH<10, possibly due to the dissolution of ettringite (at alkaline pH) or calcium (Ca)-antimonate. Treated APC residues, stored anoxically in the laboratory, simulating the conditions at the NOAH Langøya landfill, gave rise to decreasing concentrations of Sb in porewater, occurring exclusively as Sb(V). Concentrations of Sb decreased from 87-918μgL(-1) (day 3) to 18-69μgL(-1) (day 600). We hypothesize that an initial sorption of Sb to Fe(II)-Fe(III) hydroxides (green rust) and eventually precipitation of Ca- and Fe-antimonates (tripuhyite; FeSbO4) occurred. We conclude that Fe-rich, sulfuric acid waste is efficient to immobilize Sb in APC residues from waste incineration. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Arsenic, Antimony, Chromium, and Thallium Speciation in Water and Sediment Samples with the LC-ICP-MS Technique

    Directory of Open Access Journals (Sweden)

    Magdalena Jabłońska-Czapla

    2015-01-01

    Full Text Available Chemical speciation is a very important subject in the environmental protection, toxicology, and chemical analytics due to the fact that toxicity, availability, and reactivity of trace elements depend on the chemical forms in which these elements occur. Research on low analyte levels, particularly in complex matrix samples, requires more and more advanced and sophisticated analytical methods and techniques. The latest trends in this field concern the so-called hyphenated techniques. Arsenic, antimony, chromium, and (underestimated thallium attract the closest attention of toxicologists and analysts. The properties of those elements depend on the oxidation state in which they occur. The aim of the following paper is to answer the question why the speciation analytics is so important. The paper also provides numerous examples of the hyphenated technique usage (e.g., the LC-ICP-MS application in the speciation analysis of chromium, antimony, arsenic, or thallium in water and bottom sediment samples. An important issue addressed is the preparation of environmental samples for speciation analysis.

  4. Complement activation-related pseudoallergy in dogs following intravenous administration of a liposomal formulation of meglumine antimoniate

    Directory of Open Access Journals (Sweden)

    Raul R. Ribeiro

    2013-08-01

    Full Text Available The increasing use of nanotechnologies in advanced therapies has allowed the observation of specific adverse reactions related to nanostructures. The toxicity of a novel liposome formulation of meglumine antimoniate in dogs with visceral leishmaniasis after single dose has been investigated. Groups of 12 animals received by the intravenous route a single dose of liposomal meglumine antimoniate (group I [GI], 6.5 mg Sb/kg, empty liposomes (GII or isotonic saline (GIII. Evaluation of hematological and biochemical parameters showed no significant changes 4 days after administration. No undesired effects were registered in the GIII. However, adverse reactions were observed in 67.7% of dogs from both groups that received liposomal formulations. The side effects began moments after bolus administration and disappeared during the first 15 minutes after treatment. Prostation, sialorrhea and defecation were the most frequent clinical signs, registered in 33.3% and 41.6 % of animals from the groups GI and GII, respectively. Tachypnea, mydriasis, miosis, vomiting and cyanosis were also registered in both groups. The adverse reactions observed in this study were attributed to the activation of the complement system by lipid vesicles in a phenomenon known as Complement Activation-Related Pseudoallergy (CARPA. The influence of the physical-chemical characteristics of liposomal formulation in the triggering of CARPA is discussed.

  5. Nutritional status in patients with cutaneous leishmaniasis and a study of the effects of zinc supplementation together with antimony treatment.

    Science.gov (United States)

    Guzman-Rivero, Miguel; Rojas, Ernesto; Verduguez-Orellana, Aleida; Pardo, Henry; Torrico, Mary Cruz; Cloetens, Lieselotte; Akesson, Björn; Sejas, Edgar

    2014-01-01

    The role of micronutrient status for the incidence and clinical course of cutaneous leishmaniasis is not much studied. Still zinc supplementation in leishmaniasis has shown some effect on the clinical recovery, but the evidence in humans is limited. To compare biochemical nutritional status in cutaneous leishmaniasis patients with that in controls and to study the effects of zinc supplementation for 60 days. Twenty-nine patients with cutaneous leishmaniasis were treated with antimony for 20 days. Fourteen of them got 45 mg zinc daily and 15 of them got placebo. Biomarkers of nutritional and inflammatory status and changes in size and characteristics of skin lesions were measured. The level of transferrin receptor was higher in patients than in controls but otherwise no differences in nutritional status were found between patients and controls. No significant effects of zinc supplementation on the clinical recovery were observed as assessed by lesion area reduction and characteristics or on biochemical parameters. It is concluded that nutritional status was essentially unaffected in cutaneous leishmaniasis and that oral zinc supplementation administered together with intramuscular injection of antimony had no additional clinical benefit.

  6. Arsenic, Antimony, Chromium, and Thallium Speciation in Water and Sediment Samples with the LC-ICP-MS Technique

    Science.gov (United States)

    Jabłońska-Czapla, Magdalena

    2015-01-01

    Chemical speciation is a very important subject in the environmental protection, toxicology, and chemical analytics due to the fact that toxicity, availability, and reactivity of trace elements depend on the chemical forms in which these elements occur. Research on low analyte levels, particularly in complex matrix samples, requires more and more advanced and sophisticated analytical methods and techniques. The latest trends in this field concern the so-called hyphenated techniques. Arsenic, antimony, chromium, and (underestimated) thallium attract the closest attention of toxicologists and analysts. The properties of those elements depend on the oxidation state in which they occur. The aim of the following paper is to answer the question why the speciation analytics is so important. The paper also provides numerous examples of the hyphenated technique usage (e.g., the LC-ICP-MS application in the speciation analysis of chromium, antimony, arsenic, or thallium in water and bottom sediment samples). An important issue addressed is the preparation of environmental samples for speciation analysis. PMID:25873962

  7. Detection of pathogenic bacteria in skin lesions of patients with chiclero's ulcer: reluctant response to antimonial treatment

    Directory of Open Access Journals (Sweden)

    Isaac-Márquez Angélica Patricia

    2003-01-01

    Full Text Available We investigated the bacterial flora present in skin lesions of patients with chiclero's ulcer from the Yucatan peninsula of Mexico using conventional culture methods (11 patients, and an immunocolorimetric detection of pathogenic Streptococcus pyogenes (15 patients. Prevalence of bacteria isolated by culture methods was 90.9% (10/11. We cultured, from chiclero's ulcers (60%, pathogenic bacterial such as Staphylococcus aureus (20%, S. pyogenes (1.6%, Pseudomonas aeruginosa (1.6%, Morganella morganii (1.6%, and opportunist pathogenic bacteria such as Klebsiella spp. (20.0%, Enterobacter spp. (20%, and Enterococcus spp. (20%. We also cultured coagulase-negative staphylococci in 40% (4/10 of the remaining patients. Micrococcus spp. and coagulase-negative staphylococci constituted the bacterial genuses more frequently isolated in the normal skin of patients with chiclero's ulcer and healthy individuals used as controls. We also undertook another study to find out the presence of S. pyogenes by an immunocolorimetric assay. This study indicated that 60% (9/15 of the ulcerated lesions, but not normal controls, were contaminated with S. pyogenes. Importantly, individuals with purulent secretion and holding concomitant infections with S. pyogenes, S. aureus, P. aeruginosa, M. morganii, and E. durans took longer to heal Leishmania (L. mexicana infections treated with antimonial drugs. Our results suggest the need to eliminate bacterial purulent infections, by antibiotic treatment, before starting antimonial administration to patients with chiclero's ulcer.

  8. Determination of Antimony (III in Real Samples by Anodic Stripping Voltammetry Using a Mercury Film Screen-Printed Electrode

    Directory of Open Access Journals (Sweden)

    Olga Domínguez-Renedo

    2009-01-01

    Full Text Available This paper describes a procedure for the determination of antimony (III by differential pulse anodic stripping voltammetry using a mercury film screen-printed electrode as the working electrode. The procedure has been optimized using experimental design methodology. Under these conditions, in terms of Residual Standard Deviation (RSD, the repeatability (3.81 % and the reproducibility (5.07 % of the constructed electrodes were both analyzed. The detection limit for Sb (III was calculated at a value of 1.27×10–8 M. The linear range obtained was between 0.99 × 10–8 – 8.26 × 10–8 M. An analysis of possible effects due to the presence of foreign ions in the solution was performed and the procedure was successfully applied to the determination of antimony levels in pharmaceutical preparations and sea water samples.

  9. Evaluation of the Content of Antimony, Arsenic, Bismuth, Selenium, Tellurium and Their Inorganic Forms in Commercially Baby Foods.

    Science.gov (United States)

    Ruiz-de-Cenzano, M; Rochina-Marco, A; Cervera, M L; de la Guardia, M

    2017-12-01

    Baby foods, from the Spanish market and prepared from meat, fish, vegetables, cereals, legumes, and fruits, were analyzed to obtain the concentration of antimony (Sb), arsenic (As), bismuth (Bi), and tellurium (Te) as toxic elements and selenium (Se) as essential element. An analytical procedure was employed based on atomic fluorescence spectroscopy which allowed to obtain accurate data at low levels of concentration. Values of 14 commercial samples, expressed in nanograms per gram fresh weight, ranged for Sb 0.66-6.9, As 4.5-242, Te 1.35-2.94, Bi 2.18-4.79, and Se 5.4-109. Additionally, speciation studies were performed based on data from a non-chromatographic screening method. It was concluded that tellurium and bismuth were mainly present as inorganic forms and selenium as organic form, and antimony and arsenic species depend on the ingredients of each baby food. Risk assessment considerations were made by comparing dietary intake of the aforementioned elements through the consumption of one baby food portion a day and recommended or tolerable guideline values.

  10. Compound odontoma

    Directory of Open Access Journals (Sweden)

    Monica Yadav

    2012-01-01

    Full Text Available Odontomas have been extensively reported in the dental literature, and the term refers to tumors of odontogenic origin. Though the exact etiology is still unknown, the postulated causes include: local trauma, infection, inheritance and genetic mutation. The majority of the lesions are asymptomatic; however, may be accompanied with pain and swelling as secondary complaints in some cases. Here, we report a case of a compound odontome in a 14 year old patient.

  11. Effect of antimony-oxide on the shielding properties of some sodium-boro-silicate glasses.

    Science.gov (United States)

    Zoulfakar, A M; Abdel-Ghany, A M; Abou-Elnasr, T Z; Mostafa, A G; Salem, S M; El-Bahnaswy, H H

    2017-09-01

    Some sodium-silicate-boro-antimonate glasses having the molecular composition [(20) Na 2 O - (20) SiO 2 - (60-x) B 2 O 3 - (x) Sb 2 O 3 (where x takes the values 0, 5 … or 20)] have been prepared by the melt quenching method. The melting and annealing temperatures were 1500 and 650K respectively. The amorphous nature of the prepared samples was confirmed by using X-ray diffraction analysis. Both the experimental and empirical density and molar volume values showed gradual increase with increasing Sb 2 O 3 content. The empirical densities showed higher values than those obtained experimentally, while the empirical molar volume values appeared lower than those obtained experimentally, which confirm the amorphous nature and randomness character of the studied samples. The experimentally obtained shielding parameters were approximately coincident with those obtained theoretically by applying WinXCom program. At low gamma-ray energies (0.356 and 0.662MeV) Sb 2 O 3 has approximately no effect on the total Mass Attenuation Coefficient, while at high energies it acts to increase the total Mass Attenuation Coefficient gradually. The obtained Half Value Layer and Mean Free Path values showed gradual decrease as Sb 2 O 3 was gradually increased. Also, the Total Mass Attenuation Coefficient values obtained between about 0.8 and 3.0MeV gamma-ray energy showed a slight decrease, as gamma-ray photon energy increased. This may be due to the differences between the Attenuation Coefficients of both antimony and boron oxides at various gamma-ray photon energies. However, it can be stated that the addition of Sb 2 O 3 into sodium-boro-silicate glasses increases the gamma-ray Attenuation Coefficient and the best sample is that contains 20 mol% of Sb 2 O 3 , which is operating well at 0.356 and 0.662MeV gamma-ray. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Effect of antimony segregation on the electronic properties of InAs/InAsSb superlattices

    Science.gov (United States)

    Haugan, H. J.; Szmulowicz, F.; Hudgins, J. J.; Cordonnier, L. E.; Brown, G. J.

    2017-08-01

    There has been great progress in recent years in advancing the state-of-the-art of Ga-free InAs/InAsSb superlattice (SL) materials for infrared detector applications, spurred by the observation of long minority carrier lifetimes in this material system. However, compositional and dimensional changes through antimony (Sb) segregation alter the detector properties from those originally designed. For this reason, in this work, the authors explore epitaxial conditions that can mitigate this segregation in order to produce high-quality SL materials for optimum detector performance. A nominal SL structure of 7.7 nm InAs/3.5 nm InAs0.7 Sb0.3 tailored for an approximately six-micron response at 5 K was used to optimize the epitaxial parameters. Since the growth of mixed AsSb alloys is complicated by the potential reaction of As with Sb surfaces, the authors vary the substrate temperature (Ts) in order to control the As surface reaction on a Sb surface. Experimental results indicate that the SL sample grown at the lowest investigated Ts produces the highest Sb-mole fraction x of 0.3 in InAs1-x Sbx layers, which then decreases by 21 % as the Ts increases from 395 to 440 °C. This reduction causes an approximately 30 meV blueshift in the position of the excitonic photoluminescence (PL) peak. This finding differs from the results obtained from the Ga-containing InAs/GaSb SL equivalents, where the PL peak position remains constant at about 220 meV, regardless of Ts. The Ga-free SLs generally generate a broader PL linewidth than the corresponding Ga-containing SLs due to the higher spatial Sb distribution at the hetero-interfaces engendered by Sb segregation. In order for this newly proposed Ga-free SL materials to be viable for detector applications, the material problem associated with Sb segregation needs to be adequately controlled and further mitigated.

  13. Correlation models between environmental factors and bacterial resistance to antimony and copper.

    Directory of Open Access Journals (Sweden)

    Zunji Shi

    Full Text Available Antimony (Sb and copper (Cu are toxic heavy metals that are associated with a wide variety of minerals. Sb(III-oxidizing bacteria that convert the toxic Sb(III to the less toxic Sb(V are potentially useful for environmental Sb bioremediation. A total of 125 culturable Sb(III/Cu(II-resistant bacteria from 11 different types of mining soils were isolated. Four strains identified as Arthrobacter, Acinetobacter and Janibacter exhibited notably high minimum inhibitory concentrations (MICs for Sb(III (>10 mM,making them the most highly Sb(III-resistant bacteria to date. Thirty-six strains were able to oxidize Sb(III, including Pseudomonas-, Comamonas-, Acinetobacter-, Sphingopyxis-, Paracoccus- Aminobacter-, Arthrobacter-, Bacillus-, Janibacter- and Variovorax-like isolates. Canonical correspondence analysis (CCA revealed that the soil concentrations of Sb and Cu were the most obvious environmental factors affecting the culturable bacterial population structures. Stepwise linear regression was used to create two predictive models for the correlation between soil characteristics and the bacterial Sb(III or Cu(II resistance. The concentrations of Sb and Cu in the soil was the significant factors affecting the bacterial Sb(III resistance, whereas the concentrations of S and P in the soil greatly affected the bacterial Cu(II resistance. The two stepwise linear regression models that we derived are as follows: MIC(Sb(III=606.605+0.14533 x C(Sb+0.4128 x C(Cu and MIC((Cu(II=58.3844+0.02119 x C(S+0.00199 x CP [where the MIC(Sb(III and MIC(Cu(II represent the average bacterial MIC for the metal of each soil (μM, and the C(Sb, C(Cu, C(S and C(P represent concentrations for Sb, Cu, S and P (mg/kg in soil, respectively, p<0.01]. The stepwise linear regression models we developed suggest that metals as well as other soil physicochemical parameters can contribute to bacterial resistance to metals.

  14. The presence and leachability of antimony in different wastes and waste handling facilities in Norway.

    Science.gov (United States)

    Okkenhaug, G; Almås, Å R; Morin, N; Hale, S E; Arp, H P H

    2015-11-01

    The environmental behaviour of antimony (Sb) is gathering attention due to its increasingly extensive use in various products, particularly in plastics. Because of this it may be expected that plastic waste is an emission source for Sb in the environment. This study presents a comprehensive field investigation of Sb concentrations in diverse types of waste from waste handling facilities in Norway. The wastes included waste electrical and electronic equipment (WEEE), glass, vehicle fluff, combustibles, bottom ash, fly ash and digested sludge. The highest solid Sb concentrations were found in WEEE and vehicle plastic (from 1238 to 1715 mg kg(-1)) and vehicle fluff (from 34 to 4565 mg kg(-1)). The type of acid used to digest the diverse solid waste materials was also tested. It was found that HNO3:HCl extraction gave substantially lower, non-quantitative yields compared to HNO3:HF. The highest water-leachable concentration for wastes when mixed with water at a 1 : 10 ratio were observed for plastic (from 0.6 to 2.0 mg kg(-1)) and bottom ash (from 0.4 to 0.8 mg kg(-1)). For all of the considered waste fractions, Sb(v) was the dominant species in the leachates, even though Sb(iii) as Sb2O3 is mainly used in plastics and other products, indicating rapid oxidation in water. This study also presents for the first time a comparison of Sb concentrations in leachate at waste handling facilities using both active grab samples and DGT passive samples. Grab samples target the total suspended Sb, whereas DGT targets the sum of free- and other chemically labile species. The grab sample concentrations (from 0.5 to 50 μg L(-1)) were lower than the predicted no-effect concentration (PNEC) of 113 μg L(-1). The DGT concentrations were substantially lower (from 0.05 to 9.93 μg L(-1)) than the grab samples, indicating much of the Sb is present in a non-available colloidal form. In addition, air samples were taken from the chimney and areas within combustible waste incinerators, as

  15. Real-world emission factors for antimony and other brake wear related trace elements: size-segregated values for light and heavy duty vehicles.

    Science.gov (United States)

    Bukowiecki, Nicolas; Lienemann, Peter; Hill, Matthias; Figi, Renato; Richard, Agnes; Furger, Markus; Rickers, Karen; Falkenberg, Gerald; Zhao, Yongjing; Cliff, Steven S; Prevot, Andre S H; Baltensperger, Urs; Buchmann, Brigitte; Gehrig, Robert

    2009-11-01

    Hourly trace element measurements were performed in an urban street canyon and next to an interurban freeway in Switzerland during more than one month each, deploying a rotating drum impactor (RDI) and subsequent sample analysis by synchrotron radiation X-ray fluorescence spectrometry (SR-XRF). Antimony and other brake wear associated elements were detected in three particle size ranges (2.5-10, 1-2.5, and 0.1-1 microm). The hourly measurements revealed that the effect of resuspended road dust has to be taken into account for the calculation of vehicle emission factors. Individual values for light and heavy duty vehicles were obtained for stop-and-go traffic in the urban street canyon. Mass based brake wear emissions were predominantly found in the coarse particle fraction. For antimony, determined emission factors were 11 +/- 7 and 86 +/- 42 microg km(-1) vehicle(-1) for light and heavy duty vehicles, respectively. Antimony emissions along the interurban freeway with free-flowing traffic were significantly lower. Relative patterns for brake wear related elements were very similar for both considered locations. Beside vehicle type specific brake wear emissions, road dust resuspension was found to be a dominant contributor of antimony in the street canyon.

  16. Treatment of visceral leishmaniasis in a patient with AIDS with antimony and gamma-interferon: remission and prevention of relapse by maintenance therapy with weekly pentamidine

    NARCIS (Netherlands)

    Lustig, V.; Kager, P. A.; Meenhorst, P. L.

    1995-01-01

    A 41-year-old AIDS patient with fever, nightly perspiration, diarrhoea, anaemia and leukopenia was diagnosed as having visceral leishmaniasis (VL). After 8 weeks of antimony treatment combined with gamma-interferon, given in 2 courses of 3 and 5 weeks, 12 weeks apart, the bone marrow revealed no

  17. Syntheses, crystal structures and antimicrobial activities of 6-coordinate antimony(III) complexes with tridentate 2-acetylpyridine thiosemicarbazone, bis(thiosemicarbazone) and semicarbazone ligands.

    Science.gov (United States)

    Kasuga, Noriko Chikaraishi; Onodera, Kuniaki; Nakano, Saori; Hayashi, Kunihiko; Nomiya, Kenji

    2006-07-01

    Five novel antimony(III) complexes with the mono- and bis(thiosemicarbazone) ligands of 2N1S or 4N2S donor atoms, N'-[1-(2-pyridyl)ethylidene]morpholine-4-carbothiohydrazide (Hmtsc, L1) and bis[N'-[1-(2-pyridyl)ethylidene

  18. Monitoring of copper, arsenic and antimony levels in agricultural soils impacted and non-impacted by mining activities, from three regions in Chile.

    Science.gov (United States)

    De Gregori, Ida; Fuentes, Edwar; Rojas, Mariela; Pinochet, Hugo; Potin-Gautier, Martine

    2003-04-01

    This paper reports a comparative study of the concentration of three important environmental elements that are often found together in mineral deposits and then associated with mining activities; copper, arsenic and antimony. These elements were determined in 26 different agricultural soils from regions I, II and V in Chile, zones where the most important and biggest copper industries of this country are located. As background levels of these elements in soils have not been well established, in this study, both, impacted and non-impacted agricultural soils from different regions were considered. The relationships between the concentrations of these elements in soils were also examined. The concentration ranges for copper, arsenic and antimony were 11-530; 2.7-202 and 0.42-11 mg kg(-1) respectively. The copper concentrations in non-polluted soils from the north and central zone of Chile were similar. However, three sites from the north region have copper concentration as higher as 100 mg kg(-1), values that exceed the critical concentration for copper in soils. The concentration of arsenic and antimony in the north soils were higher than in non-impacted ones and, in the case of arsenic, greatly exceeded the world average concentration reported for this element in soils. The highest arsenic and antimony concentrations were found in Calama and Quillagua soils, two different sites in the Loa valley. The arsenic/antimony concentration ratio was higher in Quillagua soil. The high concentrations of three elements determined in impacted soils from region V (Puchuncaví and Catemu valleys) clearly shows the impact produced in this zone by the industrial and mining activities developed in their proximities. At Puchuncaví valley a clear decrease was observed in copper, arsenic and antimony concentrations in soils on the function of the distance from the industrial complex "Las Ventanas", and all concentrations exceeded the reported critical values for this matrix. Instead at

  19. Determination of concentration levels of arsenic, gold and antimony in particle-size fractions of gold ore using Neutron Activation Analysis

    International Nuclear Information System (INIS)

    Nyarku, M.

    2009-02-01

    Instrumental Neutron Activation Analysis (INAA) has been used to quantify the concentrations of arsenic, gold and antimony in particle-size fractions of a gold ore. The ore, which was taken from the Ahafo project site of Newmont Ghana Gold Ltd, was first fractionated into fourteen (14) particle-size fractions using state-of-the-art analytical sieve machine. The minimum sieve mesh size used was 36 microns and grains >2000 microns were not considered for analysis. Results of the sieving were analysed with easysieve software. The < 36 microns sub fraction was found to be the optimum, hosting bulk of all three elements. For arsenic, the element was found to be highly concentrated in < 36 to +100 microns size fractions and erratically distributed from +150 microns fraction and above. For gold, in exception of the sub fraction <36 which had exceptionally high concentration, the element is distributed in all the size fractions but slightly 'plays out' in the +150 to +400 microns fractions. Antimony occurrence in the sample was relatively high in <36 microns size fraction followed by 600 - 800, 800 - 1000, 400 - 600 and 36 - 40 microns size fractions in that order. Gold content in the sample was far higher than that of arsenic and antimony. Gold concentration in the composite sample was in the range 564 - 8420 ppm. Arsenic levels were higher as compared to antimony. The range of arsenic concentration in the composite sample was 14.33 - 186.92 ppm. Antimony concentration was in the range 1.09 - 9.48 ppm. (au)

  20. Extractable copper, arsenic and antimony by EDTA solution from agricultural Chilean soils and its transfer to alfalfa plants (Medicago sativa L.).

    Science.gov (United States)

    De Gregori, Ida; Fuentes, Edwar; Olivares, David; Pinochet, Hugo

    2004-01-01

    Following our research on copper, arsenic and antimony in Chilean ecosystems, a study to understand the mobility and transport of these elements from soil to plants was carried out. So, the aim of this study, which follows on from the previous work, was to demonstrate if the total concentrations of these elements or their fractions extracted by 0.05 M EDTA pH 7 from different Chilean soils correlate with the respective total concentrations in the edible tissue of alfalfa plants collected simultaneously from 20 different sites affected or unaffected by mining activities. The highest copper fractions extracted by EDTA solutions were obtained in contaminated soils from the central region (41-69%); however the northern soils presented the highest extractable fractions of arsenic (9-34%). The antimony fraction was low in all soils (0.4-8.0%). Alfalfa plants from all contaminated sites presented high copper, arsenic and antimony concentrations (19-126 mg kg(-1), 5.7-16.3 mg kg(-1) and 0.16-1.7 mg kg(-1), respectively). Statistically significant correlations were obtained between the total contents of copper and arsenic and their respective extractable fractions in soils. Good correlations were found between elements in alfalfa plants. Correlations were also obtained between the total concentrations of three elements in soils and in alfalfa plants. However, excepting for antimony in the northern samples, higher correlation coefficients were evaluated when the extractable fractions were considered. Samples from the north region presented the highest copper transfer factor and the lowest for arsenic, in spite of the high concentration of this metalloid extracted by EDTA solution in these soils. There was not a clear trend on the transfer factor for antimony, probably due to the low content of this element in alfalfa plants and/or the low recovery obtained for this element by EDTA.

  1. Surface functionalization of mesoporous antimony doped tin oxide by metalorganic reaction

    Czech Academy of Sciences Publication Activity Database

    Müller, V.; Haase, F.; Rathouský, Jiří; Fattakhova-Rohlfing, D.

    2012-01-01

    Roč. 137, č. 1 (2012), s. 207-212 ISSN 0254-0584 Institutional support: RVO:61388955 Keywords : oxides * organometallic compounds * chemical synthesis Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.072, year: 2012

  2. Bismaleimide compounds

    Science.gov (United States)

    Adams, Johnnie E.; Jamieson, Donald R.

    1986-01-14

    Bismaleimides of the formula ##STR1## wherein R.sub.1 and R.sub.2 each independently is H, C.sub.1-4 -alkyl, C.sub.1-4 -alkoxy, C1 or Br, or R.sub.1 and R.sub.2 together form a fused 6-membered hydrocarbon aromatic ring, with the proviso that R.sub.1 and R.sub.2 are not t-butyl or t-butoxy; X is O, S or Se; n is 1-3; and the alkylene bridging group, optionally, is substituted by 1-3 methyl groups or by fluorine, form polybismaleimide resins which have valuable physical properties. Uniquely, these compounds permit extended cure times, i.e., they remain fluid for a time sufficient to permit the formation of a homogeneous melt prior to curing.

  3. Magnesium compounds

    Science.gov (United States)

    Kramer, D.A.

    2012-01-01

    Seawater and natural brines accounted for about 57 percent of magnesium compounds produced in the United States in 2011. Dead-burned magnesia was produced by Martin Marietta Magnesia Specialties LLC from well brines in Michigan. Caustic-calcined magnesia was recovered from seawater by Premier Magnesia LLC in Florida, from well brines in Michigan by Martin Marietta and from magnesite in Nevada by Premier Magnesia. Intrepid Potash Wendover LLC and Great Salt Lake Minerals Corp. recovered magnesium chloride brines from the Great Salt Lake in Utah. Magnesium hydroxide was produced from seawater by SPI Pharma Inc. in Delaware and Premier Magnesia in Florida, and by Martin Marietta from its brine operation in Michigan.

  4. Comparative Analysis of the Omics Technologies Used to Study Antimonial, Amphotericin B, and Pentamidine Resistance in Leishmania

    Directory of Open Access Journals (Sweden)

    Gagandeep Kaur

    2014-01-01

    Full Text Available Leishmaniasis is a serious threat in developing countries due to its endemic nature and debilitating symptoms. Extensive research and investigations have been carried out to learn about the mechanism of drug resistance in Leishmania but results obtained in the laboratory are not in agreement with those obtained from the field. Also the lack of knowledge about the mode of action for a number of drugs makes the study of drug resistance more complex. A major concern in recent times has been regarding the role of parasitic virulence in drug resistance for Leishmania. Researchers have employed various techniques to unravel the facts about resistance and virulence in Leishmania. With advent of advanced and more specific means of detection, further hints about probable mechanisms of conferring resistance are expected. This review aims to provide a consolidated picture along with a comparative account of the work done so far to study the mechanism of antimony, amphotericin B, and pentamidine resistance using various techniques.

  5. Theoretical Prediction of an Antimony-Silicon Monolayer (penta-Sb2Si): Band Gap Engineering by Strain Effect

    Science.gov (United States)

    Morshedi, Hosein; Naseri, Mosayeb; Hantehzadeh, Mohammad Reza; Elahi, Seyed Mohammad

    2018-04-01

    In this paper, using a first principles calculation, a two-dimensional structure of silicon-antimony named penta-Sb2Si is predicted. The structural, kinetic, and thermal stabilities of the predicted monolayer are confirmed by the cohesive energy calculation, phonon dispersion analysis, and first principles molecular dynamic simulation, respectively. The electronic properties investigation shows that the pentagonal Sb2Si monolayer is a semiconductor with an indirect band gap of about 1.53 eV (2.1 eV) from GGA-PBE (PBE0 hybrid functional) calculations which can be effectively engineered by employing external biaxial compressive and tensile strain. Furthermore, the optical characteristics calculation indicates that the predicted monolayer has considerable optical absorption and reflectivity in the ultraviolet region. The results suggest that a Sb2Si monolayer has very good potential applications in new nano-optoelectronic devices.

  6. Antimony (SbIII) reduces growth, declines photosynthesis, and modifies leaf tissue anatomy in sunflower (Helianthus annuus L.).

    Science.gov (United States)

    Vaculík, Marek; Mrázová, Anna; Lux, Alexander

    2015-12-01

    The role of antimony (Sb)--a non-essential trace metalloid--in physiological processes running in crops is still poorly understood. Present paper describes the effect of Sb tartrate (SbIII) on growth, Sb uptake, photosynthesis, photosynthetic pigments, and leaf tissue organization in young sunflower plants grown in hydroponics. We found that growth of below- and aboveground part was reduced with increasing concentration of Sb in the medium. Although Sb was mostly taken up by sunflower roots and only small part (1-2%) was translocated to the shoots, decline in photosynthesis, transpiration, and decreased content of photosynthetic pigments were observed. This indicates that despite relatively low mobility of Sb in root-shoot system, Sb in shoot noticeably modifies physiological status and reduced plant growth. Additionally, leaf anatomical changes indicated that Sb reduced the size of intercellular spaces and made leaf tissue more compact.

  7. Enhanced Removal of Arsenic and Antimony in the Mining Site by Calcined γ-Fe2O3/Layered Double Hydroxide Nanocomposite

    Science.gov (United States)

    Lee, Sang-Ho; Choi, Heechul; Kim, Kyoung-Woong

    2016-04-01

    Arsenic (As) and Antimony (Sb) have been recognized as harmful contaminants in aquatic environment due to its high toxicity and carcinogenicity. Especially, the contamination of arsenic in the mining areas is considered as a serious emerging environmental issue in Korea. Due to the hazardous effect of arsenic, the United States Environmental Protection Agency (US EPA) regulated maximum contamination level of arsenic to 10 μg/L in drinking water. The harmful effect on human health by excessive intake of antimony was also reported by previous studies, and severe contamination level (100 - 7,000 μg/L) of antimony reported in surface and groundwater of abandoned mining area in China and Slovakia. Therefore, US EPA regulated maximum contaminants level of antimony in drinking water to 6 μg/L. In order to remove anionic contaminants in drinking water, various type of nanomaterials have been developed. Layered double hydroxide (LDH) is the artificial anionic clay that is based on the layered structure of positively charged brucite-like layers with interlayers of anions. The LDH is one of the promising nanomaterials for the removal of anionic contaminants because it has high selectivity for arsenic, phosphate, chromium and antimony. However, the biggest problem of LDH for wastewater treatment is that the particles cannot be easily separated after the removal of contaminants. In this study, magnetic nanoparticles (γ-Fe2O3) supported LDH nanocomposite (γ-Fe2O3/LDH) was investigated to enhance magnetic particle recovery and removal efficiency for arsenic and antimony. The calcined γ-Fe2O3/LDH nanocomposites synthesized by co-precipitation method, and the crystallographic properties of maghemite (γ-Fe2O3) and layered structure of LDH were confirmed by X-ray diffraction. The nano-sized γ-Fe2O3 (30 to 50 nm) was stably attached on the surface of LDH (100 to 150 nm) and O1s spectrum by X-ray photoelectron spectroscopy (XPS) explained that there are both physical and

  8. Synthesis of Ce(III)-doped Fe3O4 magnetic particles for efficient removal of antimony from aqueous solution

    International Nuclear Information System (INIS)

    Qi, Zenglu; Joshi, Tista Prasai; Liu, Ruiping; Liu, Huijuan; Qu, Jiuhui

    2017-01-01

    Highlights: • Doping of Ce into Fe 3 O 4 was achieved based on a facile solvothermal method. • After doping, the removal capacity was increased by 5 times for “Sb(V)” and 2 times for “Sb(III)”. • Decreasing pH improved adsorption of Sb(V) but decreased adsorption of Sb(III). • Antimony sorption mechanisms on Ce-doped Fe 3 O 4 were illustrated. - Abstract: Aqueous antimony (Sb) pollution from human activity is of great concern in drinking water due to its adverse health effect. Magnetic Fe 3 O 4 particles, with high separation ability from solution, have been considered as a low-cost Sb adsorbent for contaminants. However, the limited adsorption capacity has restricted its practical application. In this study, a solvothermal approach was developed for doping Ce(III) into Fe 3 O 4 , thereby increasing the adsorption efficacy for both Sb(III) and Sb(V). In contrast to un-doped Fe 3 O 4 , the adsorption capacity towards Sb(III) and Sb(V) in Ce-doped materials increased from 111.4 to 224.2 mg/g and from 37.2 to 188.1 mg/g at neutral pH, respectively. Based on the combined results of XPS, XRD, and FTIR, it confirmed that Ce atom successfully doped into the Fe 3 O 4 structure, resulting in the decreased particle size, increased the surface area, and isoelectric point. Furthermore, the vibrating sample magnetometer (VSM) results showed that the Ce doping process had some side effects on the primitive magnetic property, but remaining the high separation potential during water treatment. According to the high removal efficiency and magnetic property, the Ce-doped Fe 3 O 4 of great simplicity should be a promising adsorbent for aqueous Sb removal.

  9. A comparative study of antimony accumulation in plants growing in two mining areas in Iran, Moghanlo, and Patyar.

    Science.gov (United States)

    Jamali Hajiani, Naser; Ghaderian, Seyed Majid; Karimi, Naser; Schat, Henk

    2015-11-01

    Antimony occurs locally at high concentrations in some mineralized soils. Very little is known about behavior of antimony in plants. In this study, we analyzed the soil and vegetation of two mining areas in Iran, Patyar, and Moghanlo. Total Sb concentrations in soil were 358-3482 mg/kg in Moghanlo and 284-886 mg/kg in Patyar. Corresponding Sb concentrations in plant shoots were 0.8-287 and 1.3-49 mg/kg, respectively. In both areas, foliar Sb concentrations increased with acid-extractable soil Sb, although the slope was about 2-fold steeper for Patyar than for Moghanlo. Regressing the foliar concentrations on water-soluble Sb yielded identical slopes for both areas, suggesting that the soluble fraction of Sb rather than total Sb is the direct determinant of foliar Sb accumulation. Both in Patyar and Moghanlo, only a minor part of the total variance of shoot Sb was explained by soluble Sb. The major part was explained by plant species, demonstrating that plant taxonomic identity is the most important determinant of foliar Sb accumulation capacity in both areas. The translocation factor (TF) was highly variable too, with species as the only significant variance component. Only four species were able to accumulate more than 100 mg/kg Sb in their leaves. Among these species, Achillea wilhelmsii and Matthiola farinosa were by far the best Sb accumulators, with, on average, 141 and 132 mg/kg Sb in their leaves. Of these two, only Matthiola farinosa consistently maintained TF values far above unity across the whole range of soluble Sb in Moghanlo.

  10. Crystallographic study of the intermediate compounds SbZn, Sb3Zn4 and Sb2Zn3

    International Nuclear Information System (INIS)

    Adjadj, Fouzia; Belbacha, El-djemai; Bouharkat, Malek; Kerboub, Abdellah

    2006-01-01

    The processes of development of semiconductor ceramics made up of bismuth, antimony and zinc often require during their preparation to know the nature of the involved phases. For that, it is always essential to refer to the diagrams of balance between phases of the binary systems or ternary. We presented in this work the study by X-rays diffraction relating to the intermediate compounds SbZn, Sb 3 Zn 4 and Sb 2 Zn 3 . The analysis by X-rays is often useful to give supplement the results of the other experimental methods

  11. Hausa verbal compounds

    NARCIS (Netherlands)

    McIntyre, Joseph Anthony

    2006-01-01

    Verbal compounds abound in Hausa (a Chadic language). A very broad definition of Hausa verbal compounds (henceforth: VC) is “a compound with a verb”. Four types of verbal compound are analysed: V[erb]+X compounds, PAC+V compounds (a PAC is a pronoun complex indicating TAM), VCs with a ma prefix

  12. Chemistry of green encapsulating molding compounds at interfaces with other materials in electronic devices

    Energy Technology Data Exchange (ETDEWEB)

    Scandurra, A.; Zafarana, R.; Tenya, Y.; Pignataro, S

    2004-07-31

    The interface chemistry between encapsulating epoxy phenolic molding compound (EMC) containing phosphorous based organic flame retardant (the so called 'green materials') and copper oxide-hydroxide and aluminum oxide-hydroxide surfaces have been studied in comparison with 'conventional' EMC containing bromine and antimony as flame retardant. These green materials are designed to reduce the presence of toxic elements in the electronic packages and, consequently, in the environment. For the study were used a Scanning Acoustic Microscopy for delamination measurements, a dynamometer for the pull strength measurements and an ESCA spectrometer for chemical analysis of the interface. The general behavior of the green compound in terms of delamination, adhesion, and corrosion is found better or at least comparable than that of the conventional EMC.

  13. Relative SHG measurements of metal thin films: Gold, silver, aluminum, cobalt, chromium, germanium, nickel, antimony, titanium, titanium nitride, tungsten, zinc, silicon and indium tin oxide

    Directory of Open Access Journals (Sweden)

    Franklin Che

    Full Text Available We have experimentally measured the surface second-harmonic generation (SHG of sputtered gold, silver, aluminum, zinc, tungsten, copper, titanium, cobalt, nickel, chromium, germanium, antimony, titanium nitride, silicon and indium tin oxide thin films. The second-harmonic response was measured in reflection using a 150 fs p-polarized laser pulse at 1561 nm. We present a clear comparison of the SHG intensity of these films relative to each other. Our measured relative intensities compare favorably with the relative intensities of metals with published data. We also report for the first time to our knowledge the surface SHG intensity of tungsten and antimony relative to that of well known metallic thin films such as gold and silver. Keywords: Surface second-harmonic generation, Nonlinear optics, Metal thin films

  14. An improved method for the determination of trace levels of arsenic and antimony in geological materials by automated hydride generation-atomic absorption spectroscopy

    Science.gov (United States)

    Crock, J.G.; Lichte, F.E.

    1982-01-01

    An improved, automated method for the determination of arsenic and antimony in geological materials is described. After digestion of the material in sulfuric, nitric, hydrofluoric and perchloric acids, a hydrochloric acid solution of the sample is automatically mixed with reducing agents, acidified with additional hydrochloric acid, and treated with a sodium tetrahydroborate solution to form arsine and stibine. The hydrides are decomposed in a heated quartz tube in the optical path of an atomic absorption spectrometer. The absorbance peak height for arsenic or antimony is measured. Interferences that exist are minimized to the point where most geological materials including coals, soils, coal ashes, rocks and sediments can be analyzed directly without use of standard additions. The relative standard deviation of the digestion and the instrumental procedure is less than 2% at the 50 ??g l-1 As or Sb level. The reagent-blank detection limit is 0.2 ??g l-1 As or Sb. ?? 1982.

  15. Comparative acute toxicity of gallium(III), antimony(III), indium(III), cadmium(II), and copper(II) on freshwater swamp shrimp (Macrobrachium nipponense).

    Science.gov (United States)

    Yang, Jen-Lee

    2014-04-01

    Acute toxicity testing were carried out the freshwater swamp shrimp, Macrobrachium nipponense, as the model animal for the semiconductor applied metals (gallium, antimony, indium, cadmium, and copper) to evaluate if the species is an suitable experimental animal of pollution in aquatic ecosystem. The static renewal test method of acute lethal concentrations determination was used, and water temperature was maintained at 24.0 ± 0.5°C. Data of individual metal obtained from acute toxicity tests were determined using probit analysis method. The median lethal concentration (96-h LC50) of gallium, antimony, indium, cadmium, and copper for M. nipponense were estimated as 2.7742, 1.9626, 6.8938, 0.0539, and 0.0313 mg/L, respectively. Comparing the toxicity tolerance of M. nipponense with other species which exposed to these metals, it is obviously that the M. nipponense is more sensitive than that of various other aquatic animals.

  16. Simultaneous determination of asrenic, mercury, antimony and selenium in biological materials with prior collection of gaseous products followed by neutron activation analysis

    International Nuclear Information System (INIS)

    Wu, C.Y.; Chen, P.Y.; Yang, M.H.

    1986-01-01

    A method combining prior collection of gaseous products with subsequent neutron activation analysis has been developed for simultaneous determination of traces of arsenic, mercury, antimony and selenium in biological materials. The generation of hydrides of arsenic, antimony and selenium and cold vapor of mercury in the generation and collection system was investigated by the use of radiotracers of the respective elements. The result indicates that selenium and mercury can be completely evaporated from the digested sample solution in 5M HCl with the addition of 5% sodium tetrahydroborate solution, while additional reduction process by potassium iodide and ascorbic acid is needed for complete evaporation of arsenic and antiomony. The gaseous products were collected in a quartz tube for neutron irradiation. The detection limits of these elements were found to be in the range of 10 -7 to 10 -8 g under the present experimental conditions. The reliability was checked with NBS standard reference materisl. (author)

  17. Molecular precursors for the phase-change material germanium-antimony-telluride, Ge{sub 2}Sb{sub 2}Te{sub 5} (GST)

    Energy Technology Data Exchange (ETDEWEB)

    Harmgarth, Nicole; Zoerner, Florian; Engelhardt, Felix; Edelmann, Frank T. [Chemisches Institut, Otto-von-Guericke-Universitaet Magdeburg (Germany); Liebing, Phil [Laboratorium fuer Anorganische Chemie, ETH Zuerich (Switzerland); Burte, Edmund P.; Silinskas, Mindaugas [Institut fuer Mikro- und Sensorsysteme, Otto-von-Guericke-Universitaet Magdeburg (Germany)

    2017-10-04

    This review provides an overview of the precursor chemistry that has been developed around the phase-change material germanium-antimony-telluride, Ge{sub 2}Sb{sub 2}Te{sub 5} (GST). Thin films of GST can be deposited by employing either chemical vapor deposition (CVD) or atomic layer deposition (ALD) techniques. In both cases, the success of the layer deposition crucially depends on the proper choice of suitable molecular precursors. Previously reported processes mainly relied on simple alkoxides, alkyls, amides and halides of germanium, antimony, and tellurium. More sophisticated precursor design provided a number of promising new aziridinides and guanidinates. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  18. Reducing plant radiation fields by source term reduction - tracking cobalt and antimony to their sources at Gentilly-2

    International Nuclear Information System (INIS)

    Gauthier, P.; Guzonas, D.A.

    2006-01-01

    Gentilly-2 NGS is experiencing high radiation fields in the fuelling machine vaults. These high fields make maintenance outages more expensive and their management more complicated. As part of the station refurbishment project, a task group was created to identify the cause of the high fields and make recommendations to prevent their reoccurrence in the second (post-refurbishment) operating cycle. To identify the root cause of the problem, the task group decided to analyse the primary heat transport system (PHTS), the fuel handling system and their inter-relation. Gentilly-2 has had to manage a unique (to CANDU) problem arising from antimony released from the main heat transport pump seals. Antimony deposits on in-core surfaces, becomes activated, and subsequently can be released, especially under oxidizing coolant conditions. It then becomes incorporated into the magnetite deposits on PHTS piping, including the steam generators and inlet feeders. Gentilly-2 has focused a great deal of effort on managing antimony over the last 15 years. As a result of these initiatives, radioantimony fields have been quite effectively managed since 1997, resulting in a decrease in their relative contribution to the total fields. The decrease in radioantimony fields highlighted the significant contribution of 60 Co cobalt activity; the high levels of both radioantimony and 60 Co differentiate Gentilly-2 from other CANDU 6 plants. Two types of 59 Co sources are present in the CANDU PHTS. High surface area materials such as steam generator tubes and feeder pipes contain trace concentrations of 59 Co as an impurity, which can be released by corrosion. Low surface area materials such as Stellites contain high concentrations of 59 Co that can be released as either corrosion or wear products. After assessing potential cobalt sources, the task group concluded that PHTS materials were not likely the origin of the high 60 Co fields. The major PHTS components identified as cobalt sources have

  19. Elimination of the inter-element interferences of iron, gold, molybdenum, tin and antimony when determined in organic solvents by flame atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Aneva, Zara; Arpadjan, Sonja

    1988-01-01

    The mutual interferences in the flame atomic absorption spectrometric determination of iron, gold, molybdenum, tin and antimony after their extraction - pre-concentration as chloride complexes from platinum solutions into isobutyl methyl ketone are investigated. It is suggested that the interferences are caused by chemical reactions in the flame and are influenced by the flame characteristics. The possibility of eliminating the interferences by addition of long-chain quaternary ammonium salts is discussed. (author)

  20. Structural, optical and electrical properties of copper antimony sulfide thin films grown by a citrate-assisted single chemical bath deposition

    Science.gov (United States)

    Loranca-Ramos, F. E.; Diliegros-Godines, C. J.; Silva González, R.; Pal, Mou

    2018-01-01

    Copper antimony sulfide (CAS) has been proposed as low toxicity and earth abundant absorber materials for thin film photovoltaics due to their suitable optical band gap, high absorption coefficient and p-type electrical conductivity. The present work reports the formation of copper antimony sulfide by chemical bath deposition using sodium citrate as a complexing agent. We show that by tuning the annealing condition, one can obtain either chalcostibite or tetrahedrite phase. However, the main challenge was co-deposition of copper and antimony as ternary sulfides from a single chemical bath due to the distinct chemical behavior of these metals. The as-deposited films were subjected to several trials of thermal treatment using different temperatures and time to find the optimized annealing condition. The films were characterized by different techniques including Raman spectroscopy, X-ray diffraction (XRD), profilometer, scanning electron microscopy (SEM), UV-vis spectrophotometer, and Hall Effect measurements. The results show that the formation of chalcostibite and tetrahedrite phases is highly sensitive to annealing conditions. The electrical properties obtained for the chalcostibite films varied as the annealing temperature increases from 280 to 350 °C: hole concentration (n) = 1017-1018 cm-3, resistivity (ρ) = 1.74-2.14 Ωcm and carrier mobility (μ) = 4.7-9.26 cm2/Vseg. While for the tetrahedrite films, the electrical properties were n = 5 × 1019 cm-3, μ = 18.24 cm2/Vseg, and ρ = 5.8 × 10-3 Ωcm. A possible mechanism for the formation of ternary copper antimony sulfide has also been proposed.

  1. Synthetic aspects, spectral, thermal studies and antimicrobial screening on bis(N,N-dimethyldithiocarbamato-S,S‧)antimony(III) complexes with oxo or thio donor ligands

    Science.gov (United States)

    Chauhan, H. P. S.; Carpenter, Jaswant; Joshi, Sapana

    2014-09-01

    The bis(N,N-dimethyldithiocarbamato-S,S‧)antimony(III) complexes have been obtained by the reaction of chloro bis(N,N-dimethyldithiocarbamato-S,S‧)antimony(III) with corresponding oxo or thio donor ligands such as sodium benzoate 1, sodium thioglycolate 2, phenol 3, sodium 1-propanethiolate 4, potassium thioacetate 5, sodium salicylate 6, ethane-1,2-dithiolate 7 and disodium oxalate 8. These complexes have been characterized by the physicochemical [melting point, molecular weight determination and elemental analysis (C, H, N, S and Sb)], spectral [UV-Visible, FT-IR, far IR, NMR (1H and 13C)], thermogravimetric (TG & DTA) analysis, ESI-Mass and powder X-ray diffraction studies. Thermogravimetric analysis of the complexes confirmed the final decomposition product as highly pure antimony sulfide (Sb2S3) and powder X-ray diffraction studies show that the complexes are in lower symmetry with monoclinic crystal lattice and nano-ranged particle size (11.51-20.82 nm). The complexes have also been screened against some bacterial and fungal strains for their antibacterial and antifungal activities and compared with standard drugs. These show that the complexes have greater activities against some human pathogenic bacteria and fungi than the activities of standard drugs.

  2. Synthetic aspects, spectral, thermal studies and antimicrobial screening on bis(N,N-dimethyldithiocarbamato-S,S')antimony(III) complexes with oxo or thio donor ligands.

    Science.gov (United States)

    Chauhan, H P S; Carpenter, Jaswant; Joshi, Sapana

    2014-09-15

    The bis(N,N-dimethyldithiocarbamato-S,S')antimony(III) complexes have been obtained by the reaction of chloro bis(N,N-dimethyldithiocarbamato-S,S')antimony(III) with corresponding oxo or thio donor ligands such as sodium benzoate 1, sodium thioglycolate 2, phenol 3, sodium 1-propanethiolate 4, potassium thioacetate 5, sodium salicylate 6, ethane-1,2-dithiolate 7 and disodium oxalate 8. These complexes have been characterized by the physicochemical [melting point, molecular weight determination and elemental analysis (C, H, N, S and Sb)], spectral [UV-Visible, FT-IR, far IR, NMR (1H and 13C)], thermogravimetric (TG & DTA) analysis, ESI-Mass and powder X-ray diffraction studies. Thermogravimetric analysis of the complexes confirmed the final decomposition product as highly pure antimony sulfide (Sb2S3) and powder X-ray diffraction studies show that the complexes are in lower symmetry with monoclinic crystal lattice and nano-ranged particle size (11.51-20.82 nm). The complexes have also been screened against some bacterial and fungal strains for their antibacterial and antifungal activities and compared with standard drugs. These show that the complexes have greater activities against some human pathogenic bacteria and fungi than the activities of standard drugs. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Determination of antimony by electrochemical hydride generation atomic absorption spectrometry in samples with high iron content using chelating resins as on-line removal system

    International Nuclear Information System (INIS)

    Bolea, E.; Arroyo, D.; Laborda, F.; Castillo, J.R.

    2006-01-01

    A method for the removal of the interference caused by iron on electrochemical generation of stibine is proposed. It consists of a chelating resin Chelex 100 column integrated into a flow injection system and coupled to the electrochemical hydride generator quartz tube atomic absorption spectrometer (EcHG-QT-AAS). Iron, as Fe(II), is retained in the column with high efficiency, close to 99.9% under optimal conditions. No significant retention was observed for Sb(III) under same conditions and a 97 ± 5% signal recovery was achieved. An electrochemical hydride generator with a concentric configuration and a reticulated vitreous carbon cathode was employed. The system is able to determine antimony concentrations in the range of ng ml -1 in presence of iron concentrations up to 400 mg l -1 . The procedure was validated by analyzing PACS-2 marine sediments reference material with a 4% (w/w) iron content and a [Fe]:[Sb] ratio of 4000:1, which caused total antimony signal suppression on the electrochemical hydride generation system. A compost sample with high iron content (0.7%, w/w), was also analyzed. A good agreement was found on both samples with the certified value and the antimony concentration determined by ICP-MS, respectively

  4. The use of silver nanoparticles as an effective modifier for the determination of arsenic and antimony by electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Gunduz, S., E-mail: semagunduz@itu.edu.t [Istanbul Technical University, Faculty of Science and Letters, Department of Chemistry, 34469, Maslak-Istanbul (Turkey); Akman, S., E-mail: akmans@itu.edu.t [Istanbul Technical University, Faculty of Science and Letters, Department of Chemistry, 34469, Maslak-Istanbul (Turkey); Baysal, A., E-mail: baysalas@itu.edu.t [Istanbul Technical University, Faculty of Science and Letters, Department of Chemistry, 34469, Maslak-Istanbul (Turkey); Kahraman, M., E-mail: mkahraman@yeditepe.edu.t [Yeditepe University, Faculty of Engineering and Architecture, Department of Genetics and Bioengineering, 34755 Kayisdagi-Istanbul (Turkey)

    2010-04-15

    Silver nanoparticles (AgNPs) were proposed as a new chemical modifier for the elimination of interferences when determining arsenic and antimony in aqueous NaCl or Na{sub 2}SO{sub 4} solutions and in sea-water by electrothermal atomic absorption spectrometry. For this purpose, the AgNPs were prepared simply by reducing silver nitrate with sodium citrate. The effects of pyrolysis and atomization temperatures and the amounts of interferents and modifiers on the sensitivities of these elements were investigated. In the presence of the proposed modifier, a pyrolysis temperature of at least 1100 deg. C for arsenic and 900 deg. C for antimony could be applied without the loss of analytes, and the interferences were greatly reduced to allow for interference-free determination. The detection limits (N = 10, 3sigma) for arsenic and antimony were 0.022 ng and 0.046 ng, respectively. AgNPs are cheaper and more available compared to many other modifiers. No background was detected, and the blank values were negligible.

  5. A new cloud point extraction procedure for determination of inorganic antimony species in beverages and biological samples by flame atomic absorption spectrometry.

    Science.gov (United States)

    Altunay, Nail; Gürkan, Ramazan

    2015-05-15

    A new cloud-point extraction (CPE) for the determination of antimony species in biological and beverages samples has been established with flame atomic absorption spectrometry (FAAS). The method is based on the fact that formation of the competitive ion-pairing complex of Sb(III) and Sb(V) with Victoria Pure Blue BO (VPB(+)) at pH 10. The antimony species were individually detected by FAAS. Under the optimized conditions, the calibration range for Sb(V) is 1-250 μg L(-1) with a detection limit of 0.25 μg L(-1) and sensitive enhancement factor of 76.3 while the calibration range for Sb(III) is 10-400 μg L(-1) with a detection limit of 5.15 μg L(-1) and sensitive enhancement factor of 48.3. The precision as a relative standard deviation is in range of 0.24-2.35%. The method was successfully applied to the speciative determination of antimony species in the samples. The validation was verified by analysis of certified reference materials (CRMs). Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Arsenic and antimony geochemistry of mine wastes, associated waters and sediments at the Giant Mine, Yellowknife, Northwest Territories, Canada

    Science.gov (United States)

    Fawcett, Skya E.; Jamieson, Heather E.; Nordstrom, D. Kirk; McCleskey, R. Blaine

    2015-01-01

    Elevated levels of arsenic (As) and antimony (Sb) in water and sediments are legacy residues found downstream from gold-mining activities at the Giant Mine in Yellowknife, Northwest Territories (NWT), Canada. To track the transport and fate of As and Sb, samples of mine-waste from the mill, and surface water, sediment, pore-water, and vegetation downstream of the mine were collected. Mine waste, pore-water, and sediment samples were analyzed for bulk chemistry, and aqueous and solid-state speciation. Sediment and vegetation chemistry were evaluated using scanning electron microscope imaging, synchrotron-based element mapping and electron microprobe analysis. The distributions of As and Sb in sediments were similar, yet their distributions in the corresponding pore-waters were mostly dissimilar, and the mobility of As was greater than that of Sb. Competition for sorption sites is the most likely cause of elevated Sb concentrations in relatively oxidized pore-water and surface water. The aqueous and solid-state speciation of As and Sb also differed. In pore-water, As(V) dominated in oxidizing environments and As(III) in reducing environments. In contrast, the Sb(V) species dominated in all but one pore-water sample, even under reducing conditions. Antimony(III) appears to preferentially precipitate or adsorb onto sulfides as evidenced by the prevalence of an Sb(III)-S secondary solid-phase and the lack of Sb(III)(aq) in the deeper zones. The As(V)–O solid phase became depleted with depth below the sediment–water interface, and the Sb(V)–O phase persisted under relatively reducing conditions. In the surficial zone at a site populated by Equisetum fluviatile (common horsetail), As and Sb were associated with organic material and appeared mobile in the root zone. In the zone below active plant growth, As and Sb were associated primarily with inorganic phases suggesting a release and reprecipitation of these elements upon plant death. The co-existence of reduced

  7. A novel voltammetric sensor based on carbon nanotubes and nanoparticles of antimony tin oxide for the determination of ractopamine.

    Science.gov (United States)

    Baytak, Aysegul Kutluay; Teker, Tugce; Duzmen, Sehriban; Aslanoglu, Mehmet

    2016-02-01

    An electrochemical sensor was prepared by the modification of a glassy carbon electrode (GCE) with carbon nanotubes (CNTs) and nanoparticles of antimony tin oxide (ATO). The surface layer was characterized by scanning electronmicroscopy (SEM), energy dispersive X-ray diffraction method (EDX) and ATR FT-IR spectroscopy. The proposed electrode was assessed in respect to the electro-oxidation of ractopamine. Compared with a bare GCE and a GCE electrode modified with CNTs, the ATONPs/CNTs/GCE exhibited a great catalytic activity towards the oxidation of ractopamine with a well-defined anodic peak at 600 mV. The current response was linear with the concentration of ractopamine over the range from 10 to 240 nM with a detection limit of 3.3 nM. The proposed electrode enabled the selective determination of ractopamine in the presence of high concentrations of ascorbic acid (AA), dopamine (DA) and uric acid (UA). The proposed electrode was successfully applied for the determination of ractopamine in feed and urine samples. The sensitive and selective determination of ractopamine makes the developed method of great interest for monitoring its therapeutic use and doping control purposes.

  8. Therapeutic trial of sodium antimony gluconate alone and in combination with ketoconazole in post-kala-azar dermal leishmaniasis

    Directory of Open Access Journals (Sweden)

    Rathi S

    2003-11-01

    Full Text Available BACKGROUND: Drugs used in PKDL include parenteral sodium antimony gluconate (SAG, amphotericin-B, pentamidine, and ketoconazole (KTZ. SAG is the most effective one. Given alone, SAG has to be given for a long duration, leading to poor patient compliance and treatment failure. This study was carried out to compare the effectiness of SAG alone and a combination of SAG and KTZ for sixty days. METHODS: Ten patients of PKDL were included in the study. Five patients (Group A were given SAG intravenously, in the dose of 20 mg/kg per day and five (Group B were given SAG (intravenously 20 mg/kg per day and KTZ (200 mg twice daily orally. Both treatment regimens were given for sixty days. RESULTS: In Group A, the nodules and/or plaques showed approximate 80-85% clinical improvement, and macules showed 25-30% improvement. In group B (SAG + KTZ, there was 90-95% clinical improvement in the nodules and/or plaques and 25-30% in macules. CONCLUSION: This study suggests the therapeutic superiority of the combination treatment regimen in a shorter duration but is not conclusive as the number of patients was low. Further trials are recommended.

  9. Ultrasound-assisted HCl-NaCl leaching of lead-rich and antimony-rich oxidizing slag.

    Science.gov (United States)

    Zhang, Rong Liang; Zhang, Xiao Fei; Tang, Shu Zhen; Huang, Ai Dong

    2015-11-01

    Lead-rich and antimony-rich oxidizing slag was subjected to regular HCl-NaCl leaching, with the experimental conditions optimized under which ultrasound was introduced. After only 15 min of ultrasound-assisted leaching, the leaching rate of Sb resembled that after 45 min of regular leaching. Ultrasonic treatment considerably elevated the leaching rates of Sb and Pb, and shortened the leaching time. With the decrease of particle size, the leaching rate of Sb and Pb increased gradually. Especially, as the particle size of the slag was greater than 0.217 mm, the ultrasonic leaching effects of Sb and Pb were significantly higher than that of regular leaching effects. The temperature exhibited great effect on ultrasonic leaching performance. As the temperature increased, the leaching rates of Sb and Pb increased step by step. In case the temperature was higher than 85°C, the increasing speed of the leaching rates for Sb and Pb tended to be slow. Increasing ultrasonic power could augment the leaching rate or accelerate the procedure till the same leaching rate. However, since ultrasound failed to energize the formation of new reaction pathways, the maximum leaching rates of Sb and Pb were determined by their phase compositions rather than by ultrasonic field. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Thickness-Dependent Bioelectrochemical and Energy Applications of Thickness-Controlled Meso-Macroporous Antimony-Doped Tin Oxide

    Directory of Open Access Journals (Sweden)

    Daniel Mieritz

    2018-04-01

    Full Text Available Coatings of hierarchically meso-macroporous antimony-doped tin oxide (ATO enable interfacing adsorbed species, such as biomacromolecules, with an electronic circuit. The coating thickness is a limiting factor for the surface coverage of adsorbates, that are electrochemically addressable. To overcome this challenge, a carbon black-based templating method was developed by studying the composition of the template system, and finding the right conditions for self-standing templates, preventing the reaction mixture from flowing out of the mask. The thicknesses of as-fabricated coatings were measured using stylus profilometry to establish a relationship between the mask thickness and the coating thickness. Cyclic voltammetry was performed on coatings with adsorbed cytochrome c to check whether the entire coating thickness was electrochemically addressable. Further, bacterial photosynthetic reaction centers were incorporated into the coatings, and photocurrent with respect to coating thickness was studied. The template mixture required enough of both carbon black and polymer, roughly 7% carbon black and 6% poly(ethylene glycol. Coatings were fabricated with thicknesses approaching 30 µm, and thickness was shown to be controllable up to at least 15 µm. Under the experimental conditions, photocurrent was found to increase linearly with the coating thickness, up to around 12 µm, above which were diminished gains.

  11. Respirable antimony and other trace-elements inside and outside an elementary school in Flagstaff, AZ, USA

    International Nuclear Information System (INIS)

    Majestic, Brian J.; Turner, Joseph A.; Marcotte, Aurelie R.

    2012-01-01

    Because people spend almost 90% of their time indoors, ambient air monitors may severely underestimate actual exposure to atmospheric particulate matter (PM). Therefore, it becomes increasingly important to better understand the microenvironments where people are spending their time. For preadolescent children, the best estimates of exposure may be inside of their school. In this study, 11 size fractions of PM were collected inside and outside of an elementary school in Flagstaff, AZ, USA. In particles −3 — greater than many urban areas around the world. Cu:Sb ratios and size distribution functions suggest that the excess source of PM1 indoor Sb results from the suspension of embedded Sb (used as a flame retardant) in the carpeting. This is the first study to observe elevated submicron Sb in schools and further studies are required to determine if this is a widespread health risk. -- Highlights: ► Atmospheric particulate matter (PM) was collected inside and outside an elementary school. ► Size-resolved trace metal and mass concentrations were measured. ► Indoor / Outdoor ratios of PM mass were very large for particles larger than 1 µm and about unity for particles < 1 µm. ► Most of the metal mass was found to originate from crustal sources. ► Highly elevated levels of antimony were measured – most likely from the resuspension of Sb embedded in carpeting.

  12. Influence of silicon treatment on antimony uptake and translocation in rice genotypes with different radial oxygen loss.

    Science.gov (United States)

    Zhang, Liping; Yang, Qianqian; Wang, Shiliang; Li, Wanting; Jiang, Shaoqing; Liu, Yan

    2017-10-01

    Antimony (Sb) pollution in soil may have a negative impact on the health of people consuming rice. This study investigated the effect of silicon (Si) application on rice biomass, iron plaque formation, and Sb uptake and speciation in rice plants with different radial oxygen loss (ROL) using pot experiments. The results demonstrated that Si addition increased the biomass of straw and grain, but had no obvious impact on the root biomass. Indica genotypes with higher ROL underwent greater iron plaque formation and exhibited more Sb sequestration in iron plaque. Silicon treatments increased iron levels in iron plaque from the different genotypes but decreased the total Sb concentration in root, straw, husk, and grain. In addition, Si treatment reduced the inorganic Sb concentrations but slightly increased the trimethylantimony (TMSb) concentrations in rice straw. Moreover, rice straw from hybrid genotypes accumulated higher concentrations of TMSb and inorganic Sb than that from indica genotypes. The conclusions from this study indicate that Sb contamination in rice can be efficiently reduced by applying Si treatment and selecting genotypes with high ROL. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Structural and optical changes induced by incorporation of antimony into InAs/GaAs(001) quantum dots

    International Nuclear Information System (INIS)

    Taboada, A. G.; Alonso-Alvarez, D.; Alen, B.; Rivera, A.; Ripalda, J. M.; Llorens, J. M.; Martin-Sanchez, J.; Gonzalez, Y.; Sanchez, A. M.; Beltran, A. M.; Molina, S. I.; Bozkurt, M.; Ulloa, J. M.; Koenraad, P. M.; Garcia, J. M.

    2010-01-01

    We present experimental evidence of Sb incorporation inside InAs/GaAs(001) quantum dots exposed to an antimony flux immediately before capping with GaAs. The Sb composition profile inside the nanostructures as measured by cross-sectional scanning tunneling and electron transmission microscopies show two differentiated regions within the quantum dots, with an Sb rich alloy at the tip of the quantum dots. Atomic force microscopy and transmission electron microscopy micrographs show increased quantum-dot height with Sb flux exposure. The evolution of the reflection high-energy electron-diffraction pattern suggests that the increased height is due to changes in the quantum-dot capping process related to the presence of segregated Sb atoms. These structural and compositional changes result in a shift of the room-temperature photoluminescence emission from 1.26 to 1.36 μm accompanied by an order of magnitude increase in the room-temperature quantum-dot luminescence intensity.

  14. High-throughput combinatorial chemical bath deposition: The case of doping Cu (In, Ga) Se film with antimony

    Science.gov (United States)

    Yan, Zongkai; Zhang, Xiaokun; Li, Guang; Cui, Yuxing; Jiang, Zhaolian; Liu, Wen; Peng, Zhi; Xiang, Yong

    2018-01-01

    The conventional methods for designing and preparing thin film based on wet process remain a challenge due to disadvantages such as time-consuming and ineffective, which hinders the development of novel materials. Herein, we present a high-throughput combinatorial technique for continuous thin film preparation relied on chemical bath deposition (CBD). The method is ideally used to prepare high-throughput combinatorial material library with low decomposition temperatures and high water- or oxygen-sensitivity at relatively high-temperature. To check this system, a Cu(In, Ga)Se (CIGS) thin films library doped with 0-19.04 at.% of antimony (Sb) was taken as an example to evaluate the regulation of varying Sb doping concentration on the grain growth, structure, morphology and electrical properties of CIGS thin film systemically. Combined with the Energy Dispersive Spectrometer (EDS), X-ray Photoelectron Spectroscopy (XPS), automated X-ray Diffraction (XRD) for rapid screening and Localized Electrochemical Impedance Spectroscopy (LEIS), it was confirmed that this combinatorial high-throughput system could be used to identify the composition with the optimal grain orientation growth, microstructure and electrical properties systematically, through accurately monitoring the doping content and material composition. According to the characterization results, a Sb2Se3 quasi-liquid phase promoted CIGS film-growth model has been put forward. In addition to CIGS thin film reported here, the combinatorial CBD also could be applied to the high-throughput screening of other sulfide thin film material systems.

  15. Immunotherapy Using Autoclaved L. Major Antigens and M. Vaccae with Meglumine Antimoniate, for the Treatment of Experimental Canine Visceral Leishmaniasis

    Directory of Open Access Journals (Sweden)

    Sh Jamshidi

    2011-09-01

    Full Text Available Background: To evaluate immunotherapy against canine visceral leishmaniasis, Leishmania ma­jor antigen and heat-killed Mycobacterium vaccae (SRL172 were used as stimulators of immune de­fense mechanisms and the results were compared with standard chemotherapy meglumine antimoni­ate.Methods: Nineteen mongrel dogs aging 1-3 years old were used in this experiment. Infection was carried out in 15 out of 19 dogs using L. infantum, isolated from a naturally infected poly-symptomatic dog.Results: All the cases showed positive serologic results by direct agglutination test during 30-60 days following inoculation. In the first group, which was under chemotherapy (GlucantimeR, one of the members showed recurrence of the disease despite rapid effect of the therapeutic protocol. Im­munotherapy using SRL172 caused complete cleaning of the parasite in group 2, but the speed was less than Glucantime. Immunotherapy using L. major antigen combined with M. vaccae in group 3 and combine administration of immunotherapy and chemotherapy in group 4 both were with relapsing of one case in each group. Group 5 and 6 were consisted of positive and negative con­trol dogs, respectively.Conclusion: Immunotherapy seems to be an adjuvant in treatment of canine leishmaniasis but it needs more investigation for final confirmation.

  16. Influence of arbuscular mycorrhizal fungi on antimony phyto-uptake and compartmentation in vegetables cultivated in urban gardens.

    Science.gov (United States)

    Pierart, Antoine; Dumat, Camille; Maes, Arthur QuyManh; Sejalon-Delmas, Nathalie

    2018-01-01

    1. Urban areas are often contaminated with various forms of persistent metal (loid) and emerging contaminants such as antimony (Sb). Thus, in the context of urban agriculture where sustainable practices such as biofertilizers application (arbuscular mycorrhizal fungi, AMF) could improve nutrient transfer from the soil to the vegetables, the effect of AMF on metal (loid) mobility and human bioaccessibility is still poorly known. 2. The role of AMF in Sb uptake by lettuce and carrot grown in artificial substrate spiked with different Sb chemical species was investigated. Plants were grown under hydroponic conditions and half of the treatments received a concentrated spore solution to obtain mycorrhized and non-mycorrhized plants. Three weeks before harvest, plants were exposed to 10 mg.L -1 of either Sb 2 O 3 or KSbO-tartrate (KSb). 3. The presence of AMF significantly increased its accumulation in carrots (all organs) with higher accumulation in roots. In lettuce, accumulation appeared to be dependent on the Sb chemical species. Moreover, it was observed for the first time that AMF changed the human bioaccessible fraction of Sb in edible organs. 4. The present results highlight a possible risk of Sb transfer from soil to edible plants cultivated in soil naturally containing AMF propagules, or when AMF are added as biofertilizers. After validating the influence of soil environment and AMF on Sb behavior in the field, these results should be considered in health risk assessments. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. 3D Cathodes of Cupric Oxide Nanosheets Coated onto Macroporous Antimony-Doped Tin Oxide for Photoelectrochemical Water Splitting.

    Science.gov (United States)

    Wang, Xu-Dong; Xu, Yang-Fan; Chen, Bai-Xue; Zhou, Ning; Chen, Hong-Yan; Kuang, Dai-Bin; Su, Cheng-Yong

    2016-10-20

    Cupric oxide (CuO), a narrow-bandgap semiconductor, has a band alignment that makes it an ideal photocathode for the renewable production of solar fuels. However, the photoelectrochemical performance of CuO is limited by its poor conductivity and short electron diffusion lengths. Herein, a three-dimensional (3D) architecture consisting of CuO nanosheets supported onto transparent conducting macroporous antimony-doped tin oxide (mpATO@CuONSs) is designed as an excellent photocathode for promoting the hydrogen evolution reaction (HER). Owing to the 3D structure affording superior light-harvesting characteristics, large contact areas with the electrolyte, and highly conductive pathways for separation and transport of charge carriers, the mpATO@CuONSs photocathode produces an impressively high photocurrent density of -4.6 mA cm -2 at 0 V versus the reversible hydrogen electrode (RHE), which is much higher than that of the CuONSs array onto planar FTO glass (-1.9 mA cm -2 ). © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Kinetic modeling of pH-dependent antimony (V) sorption and transport in iron oxide-coated sand.

    Science.gov (United States)

    Cai, Yongbing; Li, Lulu; Zhang, Hua

    2015-11-01

    Understanding the mechanisms and kinetics controlling the retention and transport of antimony (Sb) is prerequisite for evaluating the risk of groundwater contamination by the toxic element. In this study, kinetic batch and saturated miscible displacement experiments were performed to investigate effects of protonation-deprotonation reactions on sorption-desorption and transport of Sb(V) in iron oxide-coated sand (IOCS). Results clearly demonstrated that Sb(V) sorption was highly nonlinear and time dependent, where both sorption capacity and kinetic rates decreased with increasing solution pH. Breakthrough curves (BTCs) obtained at different solution pH exhibited that mobility of Sb(V) were higher under neutral to alkaline condition than under acidic condition. Because of the nonlinear and non-equilibrium nature of Sb(V) retention and transport, multi-reaction models (MRM) with equilibrium and kinetic sorption expressions were utilized successfully to simulate the experiment data. Equilibrium distribution coefficient (Ke) and reversible kinetic retention parameters (k1 and k2) of both kinetic sorption and transport experiment showed marked decrease as pH increased from 4.0 to 7.5. Surface complexation is suggested as the dominant mechanism for the observed pH-dependent phenomena, which need to be incorporated into the kinetic models to accurately simulate the reactive transport of Sb(V) in vadose zone and aquifers. Copyright © 2015. Published by Elsevier Ltd.

  19. Effects of storage temperature and time of antimony release from PET bottles into drinking water in China.

    Science.gov (United States)

    Qiao, Fei; Lei, Kun; Li, Zicheng; Liu, Qing; Wei, Zhanliang; An, Lihui; Qi, Hongli; Cui, Song

    2018-01-01

    Antimony (Sb) concentrations were measured in 10 brands of PET bottled drinking water available in supermarkets in China. To simulate general storage habits based on market research, these PET bottles with drinking water were stored for 4 weeks in a lab or a car trunk during the summer. Although the PET package material of brand A had the lowest Sb level (142.71 ± 29.81 μg/g), it showed a significant increase in Sb concentrations when stored in both the car trunk and the lab. There was significant release of Sb from the PET bottles into the water following 24 h of incubation at ≥ 40 °C (40, 50, 60, and 70 °C), especially at 70 °C. The potential health risk of Sb release from PET bottles was calculated based on daily intake values and determined to be acceptable for consumers under normal storage conditions.

  20. FACTORS ASSOCIATED TO ADHERENCE TO DIFFERENT TREATMENT SCHEMES WITH MEGLUMINE ANTIMONIATE IN A CLINICAL TRIAL FOR CUTANEOUS LEISHMANIASIS

    Directory of Open Access Journals (Sweden)

    Madelon Novato Ribeiro

    2014-07-01

    Full Text Available The favorable outcome of the treatment of a disease is influenced by the adherence to therapy. Our objective was to assess factors associated with adherence to treatment of patients included in a clinical trial of equivalence between the standard and alternative treatment schemes with meglumine antimoniate (MA in the treatment of cutaneous leishmaniasis (CL, in the state of Rio de Janeiro. Between 2008 and 2011, 57 patients with CL were interviewed using a questionnaire to collect socioeconomic data. The following methods were used for adherence monitoring: counting of vial surplus, monitoring card, Morisky test and modified Morisky test (without the question regarding the schedule; we observed 82.1% (vial return, 86.0% (monitoring card, 66.7% (Morisky test and 86.0% (modified Morisky test adherence. There was a strong correlation between the method of vial counting and the monitoring card and modified Morisky test. A significant association was observed between greater adherence to treatment and low dose of MA, as well as with a lower number of people sleeping in the same room. We recommend the use of the modified Morisky test to assess adherence to treatment of CL with MA, because it is a simple method and with a good performance, when compared to other methods.

  1. Rubber compounding and processing

    CSIR Research Space (South Africa)

    John, MJ

    2014-06-01

    Full Text Available This chapter presents an overview on the compounding and processing techniques of natural rubber compounds. The introductory portion deals with different types of rubbers and principles of rubber compounding. The primary and secondary fillers used...

  2. Room temperature electrodeposition of aluminum antimonide compound semiconductor

    International Nuclear Information System (INIS)

    Gandhi, T.; Raja, K.S.; Misra, M.

    2008-01-01

    AlSb is a group III-V compound semiconductor material that is conventionally grown by high temperature processes such as Czochralski and Bridgman methods. Development of a method to synthesize AlSb at room temperature will be more economical to help modulate the electronic properties. In this investigation, a pulsed potential electrodeposition method using a room temperature molten salt system (aluminum trichloride, AlCl 3 /1-methyl-3-ethylimidazolium chloride, EMIC) with an addition of SbCl 3 is discussed. The potential pulse parameters were established by carrying out cyclic voltammetry at different concentrations of SbCl 3 and with varying molar ratios of AlCl 3 /EMIC. Stoichiometric AlSb deposits were obtained from an acidic AlCl 3 /EMIC (1.5:1 molar ratio) melt containing 4 x 10 -3 mol/l of SbCl 3 onto an ordered TiO 2 nanotubular template. The AlSb compound was predominantly amorphous in as-deposited condition and annealing at 350 deg. C for 2 h in argon transformed into crystalline phase. The AlSb deposit showed a high resistivity in the order of 10 9 Ω-cm and a defect concentration of 10 16 cm -3 which was attributed to presence of carbon. The deposits obtained from a basic melt (0.67:1 molar ratio of AlCl 3 /EMIC) were enriched with antimony

  3. The oxygen sensitivity of a multipoint antimony electrode for tissue pH measurements. A study of the sensitivity for in vivo PO2 variations below 6 kPa.

    Science.gov (United States)

    Sjöberg, F; Edwall, G; Lund, N

    1987-02-01

    Monocrystalline micro antimony electrodes in a multipoint arrangement as described by Lund et al. were placed on the skeletal muscle surface of the rabbit. Tissue oxygen levels were measured simultaneously with the MDO (Mehrdraht Dortmund Oberfläche) oxygen electrode. The sensitivity for variations in tissue PO2 (PO2(t)) was evaluated for the antimony metal-metal oxide sensor. The sensitivity (delta E/delta log10 PO2)+/- SE was found to be 21.8 +/- 1.2 mV in the interval between 0.1 kPa and 1 kPa and 53 +/- 5 mV in the interval between 1 kPa and 6 kPa. These results are not consistent with the oxygen sensitivity of monocrystalline antimony described in vitro, but are in agreement with the findings of Nilsson & Edwall. A plausible explanation for the S-shaped oxygen sensitivity curve of antimony at oxygen levels below 10 kPa could be an interaction, at the electrode surface, between the dissolved oxygen and the oxygen bound to haemoglobin. If this is the case, the use of an antimony electrode would make possible the determination of the dissociation of oxyhaemoglobin in tissues.

  4. Crystallographic study of the intermediate compounds SbZn, Sb{sub 3}Zn{sub 4} and Sb{sub 2}Zn{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Adjadj, Fouzia [Laboratoire des etudes Physico-chimiques des Materiaux, Departement de Physique, Faculte des Sciences, Universite de Batna, 05000 Batna (Algeria); Belbacha, El-djemai [Laboratoire des etudes Physico-chimiques des Materiaux, Departement de Physique, Faculte des Sciences, Universite de Batna, 05000 Batna (Algeria)]. E-mail: Beldjem@caramail.com; Bouharkat, Malek [Laboratoire des etudes Physico-chimiques des Materiaux, Departement de Physique, Faculte des Sciences, Universite de Batna, 05000 Batna (Algeria); Kerboub, Abdellah [Laboratoire des etudes Physico-chimiques des Materiaux, Departement de Physique, Faculte des Sciences, Universite de Batna, 05000 Batna (Algeria)

    2006-08-10

    The processes of development of semiconductor ceramics made up of bismuth, antimony and zinc often require during their preparation to know the nature of the involved phases. For that, it is always essential to refer to the diagrams of balance between phases of the binary systems or ternary. We presented in this work the study by X-rays diffraction relating to the intermediate compounds SbZn, Sb{sub 3}Zn{sub 4} and Sb{sub 2}Zn{sub 3}. The analysis by X-rays is often useful to give supplement the results of the other experimental methods.

  5. Template-assisted electrodeposition of indium–antimony nanowires – Comparison of electrochemical methods

    Energy Technology Data Exchange (ETDEWEB)

    Hnida, Katarzyna, E-mail: hnida@chemia.uj.edu.pl [Department of Physical Chemistry and Electrochemistry, Jagiellonian University, Ingardena 3, 30060 Krakow (Poland); Mech, Justyna [Faculty of Non-Ferrous Metals, AGH University of Science and Technology, Al. A. Mickiewicza 30, 30059 Krakow (Poland); Sulka, Grzegorz D. [Department of Physical Chemistry and Electrochemistry, Jagiellonian University, Ingardena 3, 30060 Krakow (Poland)

    2013-12-15

    Indium antimonide (InSb) is a III–V compound semiconductor that in a form of nanowires can possess improved thermoelectrical and optical properties compared to the corresponding bulk crystal. Here, we applied three electrodeposition techniques for a fast and inexpensive template-assisted fabrication of InSb nanowires from a sodium citrate-citric acid solution at room temperature. The home-made anodic aluminum oxide (AAO) templates with the pore diameter of 100 nm were used. InSb nanowires were synthesized by potentiostatic, galvanostatic and periodic pulse reverse techniques. The morphology, composition and crystallinity of as-obtained and annealed nanowires were investigated and compared with the literature data. It was found that the potentiostatic and pulse reverse methods gave crystalline nanowires. On the other hand, the constant current density deposition results in a partially amorphous nanowire material.

  6. Layered germanium tin antimony tellurides: element distribution, nanostructures and thermoelectric properties.

    Science.gov (United States)

    Welzmiller, Simon; Rosenthal, Tobias; Ganter, Pirmin; Neudert, Lukas; Fahrnbauer, Felix; Urban, Philipp; Stiewe, Christian; de Boor, Johannes; Oeckler, Oliver

    2014-07-21

    In the system Ge-Sn-Sb-Te, there is a complete solid solution series between GeSb2Te4 and SnSb2Te4. As Sn2Sb2Te5 does not exist, Sn can only partially replace Ge in Ge2Sb2Te5; samples with 75% or more Sn are not homogeneous. The joint refinement of high-resolution synchrotron data measured at the K-absorption edges of Sn, Sb and Te combined with data measured at off-edge wavelengths unambiguously yields the element distribution in 21R-Ge(0.6)Sn(0.4)Sb2Te4 and 9P-Ge(1.3)Sn(0.7)Sb2Te5. In both cases, Sb predominantly concentrates on the position near the van der Waals gaps between distorted rocksalt-type slabs whereas Ge prefers the position in the middle of the slabs. No significant antisite disorder is present. Comparable trends can be found in related compounds; they are due to the single-side coordination of the Te atoms at the van der Waals gap, which can be compensated more effectively by Sb(3+) due to its higher charge in comparison to Ge(2+). The structure model of 21R-Ge(0.6)Sn(0.4)Sb2Te4 was confirmed by high-resolution electron microscopy and electron diffraction. In contrast, electron diffraction patterns of 9P-Ge(1.3)Sn(0.7)Sb2Te5 reveal a significant extent of stacking disorder as evidenced by diffuse streaks along the stacking direction. The Seebeck coefficient is unaffected by the Sn substitution but the thermal conductivity drops by a factor of 2 which results in a thermoelectric figure of merit ZT = ~0.25 at 450 °C for both Ge(0.6)Sn(0.4)Sb2Te4 and Ge(1.3)Sn(0.7)Sb2Te5, which is higher than ~0.20 for unsubstituted stable layered Ge-Sb-Te compounds.

  7. Speciation of inorganic antimony in polyethylene terephthalate (PET) bottled water using hydride generation atomic absorption spectrophotometry (HG-AAS)

    International Nuclear Information System (INIS)

    Markwo, Ali

    2015-07-01

    Antimony (Sb) is a regulated drinking water contaminant that has been found to leach from polyethylene terephthalate (PET) plastic containers into the waters stored in them. The common inorganic species of antimony in water are Sb(III) and Sb(V), with the former being more toxic and the latter being more soluble. In order to assess the extent to which waters stored in PET bottles are contaminated with inorganic Sb and to further examine the effect of typical storage conditions on migration rates, speciation analysis of inorganic Sb using hydride generation atomic absorption spectrophotometry (HG-AAS) was undertaken on selected PET plastic bottled waters marketed in the Greater Accra Region of Ghana. Six brands of PET plastic bottled waters were obtained at source on the day of packaging, and analyses undertaken on samples of the waters stored in the plastic containers at intervals of four weeks for twelve weeks, under three carefully chosen storage conditions distinctive of bottled water usage. Selected physicochemical properties of samples of the waters stored in the plastic containers and total Sb of samples of the plastic containers were also determined to discover the effect of some physical properties and certain major ions, and the influence of the different quality PET plastic types on Sb migration respectively. The study revealed amounts of total Sb in the PET plastic containers of the 6 brands ranging from 123.46 mg/kg to 146.45 mg/kg. The selected physicochemical properties of the waters stored in the PET plastic containers considered were pH (6.78 – 7.43), Ca2+ (1.61 – 12.39 mg/L), Mg2+ (1.00 – 4.96 mg/L), HCO3− (6.18 – 55.41 mg/L) and TDS (8.70 – 70.40 mg/L)). PET bottled waters of 5 out of the 6 brands contained Sb (initial total Sb ranging from 1.11 – 14.65 μg/L) before storage. Total Sb concentrations of the waters stored in the plastic containers were observed to increase with storage time under all the three storage conditions for

  8. Sanskrit Compound Processor

    Science.gov (United States)

    Kumar, Anil; Mittal, Vipul; Kulkarni, Amba

    Sanskrit is very rich in compound formation. Typically a compound does not code the relation between its components explicitly. To understand the meaning of a compound, it is necessary to identify its components, discover the relations between them and finally generate a paraphrase of the compound. In this paper, we discuss the automatic segmentation and type identification of a compound using simple statistics that results from the manually annotated data.

  9. A novel voltammetric sensor based on carbon nanotubes and nanoparticles of antimony tin oxide for the determination of ractopamine

    Energy Technology Data Exchange (ETDEWEB)

    Baytak, Aysegul Kutluay; Teker, Tugce; Duzmen, Sehriban; Aslanoglu, Mehmet, E-mail: maslanoglu@harran.edu.tr

    2016-02-01

    An electrochemical sensor was prepared by the modification of a glassy carbon electrode (GCE) with carbon nanotubes (CNTs) and nanoparticles of antimony tin oxide (ATO). The surface layer was characterized by scanning electron microscopy (SEM), energy dispersive X-ray diffraction method (EDX) and ATR FT-IR spectroscopy. The proposed electrode was assessed in respect to the electro-oxidation of ractopamine. Compared with a bare GCE and a GCE electrode modified with CNTs, the ATONPs/CNTs/GCE exhibited a great catalytic activity towards the oxidation of ractopamine with a well-defined anodic peak at 600 mV. The current response was linear with the concentration of ractopamine over the range from 10 to 240 nM with a detection limit of 3.3 nM. The proposed electrode enabled the selective determination of ractopamine in the presence of high concentrations of ascorbic acid (AA), dopamine (DA) and uric acid (UA). The proposed electrode was successfully applied for the determination of ractopamine in feed and urine samples. The sensitive and selective determination of ractopamine makes the developed method of great interest for monitoring its therapeutic use and doping control purposes. - Highlights: • A novel voltammetric sensor was prepared using nanoparticles of ATO and CNTs. • The ATONPs/CNTs/GCE has greatly improved the voltammetry of ractopamine. • The proposed electrode enabled a detection limit of 3.3 nM. • AA, DA and UA did not interfere with the selective detection of ractopamine. • Measurements were precise and accurate.

  10. Eficácia do sulfato de aminosidine na leishmaniose visceral grave, resistente ao tratamento com antimonial pentavalente

    Directory of Open Access Journals (Sweden)

    Cleudson Castro

    1995-09-01

    Full Text Available Descreve-se um caso de calazar grave resistente a dez cursos de antimonial petitavalente (glucantime à base de 20mg de Sb5/kg/dia, que respondeu favoravelmente ao sulfato de aminosidine intramuscular na dose de 20mg/kg/dia por 20 dias, repetido após 20 dias. O parasitismo esplénico passou de 50 parasitos por campo a 3 parasitos em 10 campos logo após a primeira série de sulfato de aminosidine, tornando-se negativo depois de sete meses. A melhora clínica foi imediata, com redução gradual da hepatoesplenomegalia, e desaparecimento 26 meses após. Neste período aumentou 13 kg. Após o uso de aminosidine a reação de Monténégro tornou-se positiva e as células mononucleares responderam quando estimuladas com antígenos de leishmânia.A grave kala-azar infection in a 14 years old boy is described. The leishmanial infection failed to respond to ten interrupted courses of glucantime of variable duration (14-56 days at a dose of 20mg Sb5/kg/day. However a favorable response ocurred to intramuscular aminosidine sulphate (20mg/kg/day for 20 days. This same regimen was repeated 20 days later. After the first treatment splenic puncture parasite density fell from 50 amastigotes per oil immersion field to 3 amastigotes in 10 fields. A further splenic puncture 7 months after treatment was negative. The marked hepatoesplenomegaly gradually resolved over 26 months follow up and he gained 13 kilogramas in weight. After aminosidine sulphate therapy his Montenegro reaction become positive and his lymphocytes responded to leishmania antigens.

  11. Microbial degradation of high impact polystyrene (HIPS), an e-plastic with decabromodiphenyl oxide and antimony trioxide

    International Nuclear Information System (INIS)

    Sekhar, Vini C.; Nampoothiri, K. Madhavan; Mohan, Arya J.; Nair, Nimisha R.; Bhaskar, Thallada; Pandey, Ashok

    2016-01-01

    Highlights: • Biodegradation of a high impact polystyrene e − plastic. • 12.4% (w/w) e plastic film lost using an isolate, Enterobacter sp. • Noted changes in the physico-chemical characteristics of degraded e-plastic film. • Polystyrene intermediates were detected in the degradation medium. • e-plastic degrading microbes displayed extracellular depolymerase activity. - Abstract: Accumulation of electronic waste has increased catastrophically and out of that various plastic resins constitute one of the leading thrown out materials in the electronic machinery. Enrichment medium, containing high impact polystyrene (HIPS) with decabromodiphenyl oxide and antimony trioxide as sole carbon source, was used to isolate microbial cultures. The viability of these cultures in the e-plastic containing mineral medium was further confirmed by triphenyl tetrazolium chloride (TTC) reduction test. Four cultures were identified by 16S rRNA sequencing as Enterobacter sp., Citrobacter sedlakii, Alcaligenes sp. and Brevundimonas diminuta. Biodegradation experiments were carried out in flask level and gelatin supplementation (0.1% w/v) along with HIPS had increased the degradation rate to a maximum of 12.4% (w/w) within 30 days. This is the first report for this kind of material. The comparison of FTIR, NMR, and TGA analysis of original and degraded e-plastic films revealed structural changes under microbial treatment. Polystyrene degradation intermediates in the culture supernatant were also detected using HPLC analysis. The gravity of biodegradation was validated by morphological changes under scanning electron microscope. All isolates displayed depolymerase activity to substantiate enzymatic degradation of e-plastic.

  12. Microbial degradation of high impact polystyrene (HIPS), an e-plastic with decabromodiphenyl oxide and antimony trioxide

    Energy Technology Data Exchange (ETDEWEB)

    Sekhar, Vini C. [Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695 019, Kerala (India); Nampoothiri, K. Madhavan, E-mail: madhavan85@hotmail.com [Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695 019, Kerala (India); Mohan, Arya J.; Nair, Nimisha R. [Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695 019, Kerala (India); Bhaskar, Thallada [Bio-Fuels Division (BFD), CSIR-Indian Institute of Petroleum (IIP), Dehradun, Uttarakhand 248005 (India); Pandey, Ashok [Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695 019, Kerala (India)

    2016-11-15

    Highlights: • Biodegradation of a high impact polystyrene e − plastic. • 12.4% (w/w) e plastic film lost using an isolate, Enterobacter sp. • Noted changes in the physico-chemical characteristics of degraded e-plastic film. • Polystyrene intermediates were detected in the degradation medium. • e-plastic degrading microbes displayed extracellular depolymerase activity. - Abstract: Accumulation of electronic waste has increased catastrophically and out of that various plastic resins constitute one of the leading thrown out materials in the electronic machinery. Enrichment medium, containing high impact polystyrene (HIPS) with decabromodiphenyl oxide and antimony trioxide as sole carbon source, was used to isolate microbial cultures. The viability of these cultures in the e-plastic containing mineral medium was further confirmed by triphenyl tetrazolium chloride (TTC) reduction test. Four cultures were identified by 16S rRNA sequencing as Enterobacter sp., Citrobacter sedlakii, Alcaligenes sp. and Brevundimonas diminuta. Biodegradation experiments were carried out in flask level and gelatin supplementation (0.1% w/v) along with HIPS had increased the degradation rate to a maximum of 12.4% (w/w) within 30 days. This is the first report for this kind of material. The comparison of FTIR, NMR, and TGA analysis of original and degraded e-plastic films revealed structural changes under microbial treatment. Polystyrene degradation intermediates in the culture supernatant were also detected using HPLC analysis. The gravity of biodegradation was validated by morphological changes under scanning electron microscope. All isolates displayed depolymerase activity to substantiate enzymatic degradation of e-plastic.

  13. The effect of trace amounts of antimony on the structure and properties of aluminum alloy A356. 2

    Energy Technology Data Exchange (ETDEWEB)

    Tuttle, B.L. (Tuttle (B.L.) (USA)); Keslinke, A. (Cast Metals Inst., Des Plaines, IL (USA)); Twarog, D.L. (American Foundrymens' Society, Des Plaines, IL (USA)); Daniels, E.J. (Argonne National Lab., IL (USA))

    1989-01-01

    This investigation was performed to determine the effect of trace amounts of antimony (Sb) on the microstructure, mechanical properties, and casting properties of strontium-modified A356.2 aluminum alloy that was cast in chemically bonded sand molds. The aluminum-silicon alloys were prepared in a high-frequency induction furnace from primary A356.2 ingot of commercial purity. Each melt was grain-refined with aluminum-titanium rod, modified with aluminum-strontium-silicon rod, and degassed with dry nitrogen. Five heats were prepared at each target level of Sb: 0.00, 0.05, 0.10, 0.15 and 0.20 wt %. Significant changes in mechanical and foundry properties resulted from changes in the morphology of the aluminum-silicon eutectic microstructure at the different Sb concentrations. The principle mechanical property affected was elongation (ductility). At an Sb concentration of 0.00%, elongation was 5.3%. At a concentration of 0.06%, elongation decreased to 2.9%. The fluidity of the alloy was also affected. At all three temperatures investigated, fluidity declined approximately 17% at 0.14% Sb relative to alloy containing no Sb. At an Sb content of 0.26%, the fluidity increased approximately 22% (relative to that at 0.14% Sb) to a value slightly higher than that of the Sr-modified alloy containing no Sb. None of the thermal analysis curves for the five levels of Sb addition indicated a cooling curve inflection that could be attributed to the presence of Sb alone. 14 refs., 9 figs., 10 tabs.

  14. Mine waste acidic potential and distribution of antimony and arsenic in waters of the Xikuangshan mine, China

    International Nuclear Information System (INIS)

    Zhou, Jianwei; Nyirenda, Mathews T.; Xie, Lina; Li, Yi; Zhou, Baolong; Zhu, Yue; Liu, Huilin

    2017-01-01

    The Xikuangshan (XKS) mine in China has vast quantities of waste material and reported antimony (Sb) and arsenic (As) contamination of water in the mine area. This study estimated the potential of acid mine drainage (AMD) generation by waste material at XKS mine by using paste pH, acid base accounting and net acid generation geochemical static tests. Distribution of Sb and As in surface and groundwater in relation to mine waste AMD producing potential was also investigated. Thirty four (34) water samples and representative samples of three mine wastes from different periods (fresh, 10 and 50 years) were collected for this study: waste rock, smelting slag and tailings. The AMD prediction shows that waste rock (from 10 year period) is acid producing while the fresh mine waste had alkaline paste pH indicating the presence of reactive carbonates. Hence AMD generation may have occurred after a long time due to dissolution of carbonates. Water analysis found Sb with higher concentration than As with means of 3.74 mg/L and 0.19 mg/L respectively. Highest Sb and As concentrations were observed in the North mine along the water flow path from waste heaps and tailing pond; Mine water in the South mine also had elevated Sb and As concentrations. Mining activities at the XKS mine have accelerated Sb and As releases because of the disturbed natural equilibrium. Proper mine waste management and collection and treatment of outflow from the waste rock heaps and tailing ponds seem to be a promising mitigation options. - Highlights: • High levels of Sb and As were detected in alkaline water at Xikuangshan mine. • Static test showed that mine waste aged over 10 years was acid generating. • Mine waste influenced the high concentration of Sb and As in water. • The Sb/As ratios in water favored Sb because of high Sb content in the ore body.

  15. Imipramine is an orally active drug against both antimony sensitive and resistant Leishmania donovani clinical isolates in experimental infection.

    Directory of Open Access Journals (Sweden)

    Sandip Mukherjee

    Full Text Available BACKGROUND: In an endeavor to find an orally active and affordable antileishmanial drug, we tested the efficacy of a cationic amphiphilic drug, imipramine, commonly used for the treatment of depression in humans. The only available orally active antileishmanial drug is miltefosine with long half life and teratogenic potential limits patient compliance. Thus there is a genuine need for an orally active antileishmanial drug. Previously it was shown that imipramine, a tricyclic antidepressant alters the protonmotive force in promastigotes, but its in vivo efficacy was not reported. METHODOLOGY/PRINCIPAL FINDINGS: Here we show that the drug is highly active against antimony sensitive and resistant Leishmania donovani in both promastigotes and intracellular amastigotes and in LD infected hamster model. The drug was found to decrease the mitochondrial transmembrane potential of Leishmania donovani (LD promastigotes and purified amastigotes after 8 h of treatment, whereas miltefosine effected only a marginal change even after 24 h. The drug restores defective antigen presenting ability of the parasitized macrophages. The status of the host protective factors TNF α, IFN γ and iNOS activity increased with the concomitant decrease in IL 10 and TGF β level in imipramine treated infected hamsters and evolution of matured sterile hepatic granuloma. The 10-day therapeutic window as a monotherapy, showing about 90% clearance of organ parasites in infected hamsters regardless of their SSG sensitivity. CONCLUSIONS: This study showed that imipramine possibly qualifies for a new use of an old drug and can be used as an effective orally active drug for the treatment of Kala-azar.

  16. A novel voltammetric sensor based on carbon nanotubes and nanoparticles of antimony tin oxide for the determination of ractopamine

    International Nuclear Information System (INIS)

    Baytak, Aysegul Kutluay; Teker, Tugce; Duzmen, Sehriban; Aslanoglu, Mehmet

    2016-01-01

    An electrochemical sensor was prepared by the modification of a glassy carbon electrode (GCE) with carbon nanotubes (CNTs) and nanoparticles of antimony tin oxide (ATO). The surface layer was characterized by scanning electron microscopy (SEM), energy dispersive X-ray diffraction method (EDX) and ATR FT-IR spectroscopy. The proposed electrode was assessed in respect to the electro-oxidation of ractopamine. Compared with a bare GCE and a GCE electrode modified with CNTs, the ATONPs/CNTs/GCE exhibited a great catalytic activity towards the oxidation of ractopamine with a well-defined anodic peak at 600 mV. The current response was linear with the concentration of ractopamine over the range from 10 to 240 nM with a detection limit of 3.3 nM. The proposed electrode enabled the selective determination of ractopamine in the presence of high concentrations of ascorbic acid (AA), dopamine (DA) and uric acid (UA). The proposed electrode was successfully applied for the determination of ractopamine in feed and urine samples. The sensitive and selective determination of ractopamine makes the developed method of great interest for monitoring its therapeutic use and doping control purposes. - Highlights: • A novel voltammetric sensor was prepared using nanoparticles of ATO and CNTs. • The ATONPs/CNTs/GCE has greatly improved the voltammetry of ractopamine. • The proposed electrode enabled a detection limit of 3.3 nM. • AA, DA and UA did not interfere with the selective detection of ractopamine. • Measurements were precise and accurate.

  17. Catalytic oxidation of light alkanes (C1-C4) by heteropoly compounds

    KAUST Repository

    Sun, Miao

    2014-01-22

    Heteropoly compounds (HPC) have revealed their potential to generate catalyst for selectively converting light alkanes to oxygenated products. There are various structures in which they are active the primary structure being that of the heteropolyanion itself, the secondary structure is the three-dimensional arrangements of polyanions, and the tertiary structure representing the manner in which the secondary structure assembles into solid particles. There are also a huge variety of elements inside the HPA. The heteropoly acids can have acidity, which varies dramatically depending on composition. This complexity of situation makes it very difficult to really have a predictive vision of their ability to activate and functionalize alkanes. However, a large amount of data reported suggests that the initial formula of the precatalyst is pivotal to direct the selectivity of the reaction toward different oxygenates. Inclusion of alternative transition metal atoms as addenda is highly influential with iron, vanadium, and antimony being particularly outstanding.

  18. Antimony doped tin oxides and their composites with tin pyrophosphates as catalyst supports for oxygen evolution reaction in proton exchange membrane water electrolysis

    DEFF Research Database (Denmark)

    Xu, Junyuan; Li, Qingfeng; Hansen, Martin Kalmar

    2012-01-01

    based on tin pyrophosphates as the catalyst support. The materials showed an overall conductivity of 0.57 S cm−1 at 130 °C under the water vapor atmosphere with a contribution of the proton conduction. Using this composite support, iridium oxide nanoparticle catalysts were prepared and characterized......Proton exchange membrane water electrolysers operating at typically 80 °C or at further elevated temperatures suffer from insufficient catalyst activity and durability. In this work, antimony doped tin oxide nanoparticles were synthesized and further doped with an inorganic proton conducting phase...

  19. Design of a Flow-Through Voltammetric Sensor Based on an Antimony-Modified Silver Electrode for Determining Lithol Rubine B in Cosmetics

    OpenAIRE

    Lai-Hao, Wang; Shu-Juan, Huang

    2011-01-01

    Lithol Rubine B (LRB; the disodium salt of 3-hydroxy-4-[(4-methyl-2-sulfophenyl) azo]-2-naphthalenecarboxylic acid) was detected using high-performance liquid chromatography with an electrochemical (antimony film on silver) detector (HPLC-ECD). For direct current (DC) mode, with the current at a constant potential, and measurements with suitable experimental parameters, a linear concentration from 0.125 to 1.80 μg/mL was found. The detection limit of our method was approximately 2.0 ng/mL. An...

  20. Antimony in the soil-water-plant system at the Su Suergiu abandoned mine (Sardinia, Italy): strategies to mitigate contamination.

    Science.gov (United States)

    Cidu, Rosa; Biddau, Riccardo; Dore, Elisabetta; Vacca, Andrea; Marini, Luigi

    2014-11-01

    This study was aimed to implement the understanding of the Sb behavior in near-surface environments, as a contribution to address appropriate mitigation actions at contaminated sites. For this purpose, geochemical data of soil (8 sites), water (29 sites), and plant (12 sites) samples were collected. The study area is located at Su Suergiu and surroundings in Sardinia (Italy), an abandoned mine area heavily contaminated with Sb, with relevant impact on water bodies that supply water for agriculture and domestic uses. Antimony in the soil horizons ranged from 19 to 4400 mg kg(-1), with highest concentrations in soils located close to the mining-related wastes, and concentrations in the topsoil much higher than in the bedrock. The Sb readily available fraction was about 2% of the total Sb in the soil. Antimony in the pore water ranged from 23 to 1700 μg L(-1), with highest values in the Sb-rich soils. The waters showed neutral to slightly alkaline pH, redox potential values indicating oxidizing conditions, electrical conductivity in the range of 0.2 to 3.7 mS cm(-1), and dissolved organic carbon ≤2 mg L(-1). The waters collected upstream of the mine have Ca-bicarbonate dominant composition, and median concentration of Sb(tot) of 1.7 μg L(-1) (that is total antimony determined in waters filtered through 0.45 μm), a value relatively high as compared with the background value (≤0.5 μg L(-1) Sb) estimated for Sardinian waters, but below the limits established by the European Union and the World Health Organization for drinking water (5 μg L(-1) Sb and 20 μg L(-1) Sb, respectively). The waters flowing in the mine area are characterized by Ca-sulfate dominant composition, and median concentrations of 7000 μg L(-1) Sb(tot). Extreme concentrations, up to 30,000 μg L(-1) Sb(tot), were observed in waters flowing out of the slag materials derived from the processing of Sb-ore. The Sb(III) was in the range of 0.8 to 760 μg L(-1) and represented up to 6% of Sb

  1. Novel superstructure of the rocksalt type and element distribution in germanium tin antimony tellurides

    Energy Technology Data Exchange (ETDEWEB)

    Rosenthal, Tobias [Department of Chemistry, Ludwig Maximilian University, Butenandtstraße 5-13, 81377 Munich (Germany); Welzmiller, Simon [Institute for Mineralogy, Crystallography and Materials Science, Leipzig University, Scharnhorststraße 20, 04275 Leipzig (Germany); Neudert, Lukas [Department of Chemistry, Ludwig Maximilian University, Butenandtstraße 5-13, 81377 Munich (Germany); Urban, Philipp [Institute for Mineralogy, Crystallography and Materials Science, Leipzig University, Scharnhorststraße 20, 04275 Leipzig (Germany); Fitch, Andy [European Synchrotron Radiation Facility, CS40220, 38043 Grenoble Cedex 9 (France); Oeckler, Oliver, E-mail: oliver.oeckler@gmx.de [Institute for Mineralogy, Crystallography and Materials Science, Leipzig University, Scharnhorststraße 20, 04275 Leipzig (Germany)

    2014-11-15

    A superstructure of the rocksalt-type observed in quenched CVT-grown single crystals of Ge{sub 3.25(7)}Sn{sub 1.10(3)}Sb{sub 1.10(3)}Te{sub 6} was elucidated by X-ray diffraction using fourfold twinned crystals (space group P3{sup ¯}m1, a=4.280(1) Å, c=20.966(3) Å). The structure is built up of distorted rocksalt-type building blocks typical for long-range ordered GST materials and substitution variants thereof. In contrast to those phases, an exclusive ABC-type cubic stacking sequence of the Te-atom layers is present. High-resolution electron microscopy reveals spheroidal domains with this structure (average diameter 25 nm) whose stacking direction is perpendicular to the 〈1 1 1〉 directions of the basic rocksalt-type structure. Additional slab-like domains with a lateral extension up to 1 µm occasionally result in a hierarchical structure motif. Due to the similar electron counts of the elements involved, resonant diffraction was used in order to elucidate the element distribution in rocksalt-type building blocks of the stable layered compound 39R-Ge{sub 3}SnSb{sub 2}Te{sub 7} (R3{sup ¯}m, a=4.24990(4) Å, c=73.4677(9) Å). Sb tends to occupy the atom site close to the van der Waals gaps while Ge concentrates in the center of the building blocks. - Graphical abstract: High-resolution transmission electron micrograph, SAED pattern and reciprocal lattice section of X-ray single crystal data of Ge{sub 3.25}Sn{sub 1.1}Sb{sub 1.1}Te{sub 6} with an 11P-type superstructure of the rocksalt type. - Highlights: • A novel superstructure of the rocksalt-type in the system Ge–Sn–Sb–Te is elucidated. • It combines the cubic stacking of the HT phase with building blocks of the RT phase. • It indicates the ordering mechanism during the phase transition of GST materials. • A hierarchical structure motif is promising with respect to the reduction of κ{sub L}. • Resonant diffraction reveals the element distribution in 39R-Ge{sub 3}SnSb{sub 2}Te{sub 7}.

  2. Electrochemical behavior of antimony and electrodeposition of Mg-Li-Sb alloys from chloride melts

    International Nuclear Information System (INIS)

    Wei Shuquan; Zhang Milin; Han Wei; Yan Yongde; Xue Yun; Zhang Meng; Zhang Bin

    2011-01-01

    Research highlights: → The electrochemical behavior of Sb(III) ions was investigated in LiCl-KCl molten salt at 673 K. → The electrochemical reduction of Sb(III) in LiCl-KCl melts occurred in a reaction step with an exchange of three electrons. → AlSb alloys were prepared in LiCl-KCl-SbCl 3 melts at 742 K by potentiostatic electrolysis at an Al electrode. → The activity of Sb and the Gibbs energy of AlSb formation was calculated. - Abstract: The electrochemical behavior of Sb(III) ions was investigated in LiCl-KCl molten salt at 673 K. The reaction mechanism and transport parameters of electroactive species were determined by transient electrochemical techniques (such as cyclic voltammetry, square wave voltammetry, chronopotentiometry and chronoamperometry) at a molybdenum electrode. The results showed that electrochemical reduction of Sb(III) in LiCl-KCl melts occurred in a reaction step with an exchange of three electrons. A voltammogram with a different scan rate in LiCl-KCl containing 1.45 x 10 -4 mol cm -3 SbCl 3 showed that the deposition/dissolution reaction of Sb(III) ions was not completely reversible. The diffusion coefficient of Sb(III) ions was 1.65(±0.01) x 10 -5 cm -2 s -1 at 673 K. The electroreduction of Sb(III) ions at an Al electrode was also studied by cyclic voltammetry and open circuit chronopotentiometry in the temperature range of 668-742 K. The redox potential of Sb(III)/Sb at an Al electrode was observed at the more positive potentials values than those at an inert electrode. This potential shift due to the formation of intermetallic compound with Al electrode. AlSb alloys were prepared in LiCl-KCl-SbCl 3 melts at 742 K by potentiostatic electrolysis at an Al electrode. The activity of Sb and the Gibbs energy of AlSb formation were also calculated. Mg-Li-Sb alloys were obtained by galvanostatic electrolysis at 673 K and the electrochemical codeposition of Mg, Li and Sb was investigated on a molybdenum electrode in Li

  3. Ultra-low carrier concentration and surface-dominant transport in antimony-doped Bi2Se3 topological insulator nanoribbons

    KAUST Repository

    Hong, Seung Sae

    2012-03-27

    A topological insulator is the state of quantum matter possessing gapless spin-locking surface states across the bulk band gap, which has created new opportunities from novel electronics to energy conversion. However, the large concentration of bulk residual carriers has been a major challenge for revealing the property of the topological surface state by electron transport measurements. Here we report the surface-state-dominant transport in antimony-doped, zinc oxide-encapsulated Bi2Se3 nanoribbons with suppressed bulk electron concentration. In the nanoribbon with sub-10-nm thickness protected by a zinc oxide layer, we position the Fermi levels of the top and bottom surfaces near the Dirac point by electrostatic gating, achieving extremely low two-dimensional carrier concentration of 2×10 11cm-2. The zinc oxide-capped, antimony-doped Bi 2Se3 nanostructures provide an attractive materials platform to study fundamental physics in topological insulators, as well as future applications. © 2012 Macmillan Publishers Limited. All rights reserved.

  4. Comparative acute toxicity of gallium(III, antimony(III, indium(III, cadmium(II, and copper(II on freshwater swamp shrimp (Macrobrachium nipponense

    Directory of Open Access Journals (Sweden)

    Jen-Lee Yang

    2014-01-01

    Full Text Available BACKGROUND: Acute toxicity testing were carried out the freshwater swamp shrimp, Macrobrachium nipponense, as the model animal for the semiconductor applied metals (gallium, antimony, indium, cadmium, and copper to evaluate if the species is an suitable experimental animal of pollution in aquatic ecosystem. RESULTS: The static renewal test method of acute lethal concentrations determination was used, and water temperature was maintained at 24.0 ± 0.5°C. Data of individual metal obtained from acute toxicity tests were determined using probit analysis method. The median lethal concentration (96-h LC50 of gallium, antimony, indium, cadmium, and copper for M. nipponense were estimated as 2.7742, 1.9626, 6.8938, 0.0539, and 0.0313 mg/L, respectively. CONCLUSIONS: Comparing the toxicity tolerance of M. nipponense with other species which exposed to these metals, it is obviously that the M. nipponense is more sensitive than that of various other aquatic animals.

  5. Impact of temperature and storage time on the migration of antimony from polyethylene terephthalate (PET) containers into bottled water in Qatar.

    Science.gov (United States)

    Al-Otoum, Fatima; Al-Ghouti, Mohammad A; Costa, Ozeas S; Khraisheh, Majeda

    2017-11-12

    Prosperity in Qatar and the consequent stresses on water resources resulted in a sustainable increase in the bottled drinking water market. Reports on health concerns and possible migration of chemicals from the plastic material into the water have driven the current investigation. This study aims to address the extent of antimony (Sb) leaching from polyethylene terephthalate (PET) water bottles subject to temperature variations (24-50 °C) due to Qatar's hot climate and improper storage conditions. A representative basket including 66 different imported and locally produced water bottles was considered. The concentrations of Sb in bottled water ranged from 0.168 to 2.263 μg/L at 24 °C and from 0.240 to 6.110 μg/L at 50 °C. Antimony concentrations in PET bottles at 24 °C was significantly lower than those at 50 °C (p = 0.0142), indicating that the temperature was a principal factor affecting the release of Sb from the plastic into the water. Although the detected Sb amounts were below the guidelines endorsed by WHO and Qatar (standard 5 μg/L) at 24 °C, the concentration measured at 50 °C was higher than the recommended WHO values (6.11 μg/L).

  6. Oral bioavailability of arsenic, antimony and a selection of metals in ashes; Oral biotillgaenglighet av arsenik, antimon och ett urval av metaller i askor

    Energy Technology Data Exchange (ETDEWEB)

    Carlsson, Christel; Bendz, David; Jones, Celia

    2008-06-15

    In an earlier study, financed by Varmeforsk, 'Q4-238 Environmental guidelines for reuse of ash in civil engineering applications', the total content of arsenic and lead was shown to determine whether or not reuse of some of the ashes in construction work is feasible. The model used to calculate the guidelines uses the total concentration of metals to evaluate the health risks resulting from exposure to the ashes. The use of total concentration can lead to overly conservative risk assessments if a significant fraction of the total metal content is not bioavailable. Better precision in the risk assessment can be given by the use of the bioavailable fraction of arsenic and lead in the model. As a result, ashes which are rejected on the basis of total metal concentration may be acceptable for use in engineering construction when the assessment is based on the bioavailable fraction. The purpose of the study was to (i) compile information on the oral bioavailability of arsenic, antimony and a selection of metals in ashes and similar materials, and on in vitro methods for determination of oral bioavailability, and (ii) experimentally estimate oral bioavailability of arsenic, antimony and some metals in a selection of ashes by analysis of the gastrointestinal bioaccessibility of these elements. The investigated elements were antimony, arsenic, lead, cadmium, copper, chromium, nickel and zinc. In the literature study performed within the project a number of static and dynamic in vitro methods simulating gastrointestinal processes of contaminants were compiled. The methods include one or several segments, i.e. mouth, stomach and intestine. Among the compiled methods, the RIVM (Rijksinstituut voor volksgesundheid en milieu) in vitro method was used in the experimental part of the project. The advantages with the method was that: the method to a high degree mimicked the human gastrointestinal processes (the method included three segments mouth, stomach, and intestine

  7. An evaluation of the migration of antimony from polyethylene terephthalate (PET) plastic used for bottled drinking water

    International Nuclear Information System (INIS)

    Chapa-Martínez, C.A.; Hinojosa-Reyes, L.; Hernández-Ramírez, A.; Ruiz-Ruiz, E.; Maya-Treviño, L.; Guzmán-Mar, J.L.

    2016-01-01

    The leaching of antimony (Sb) from polyethylene terephthalate (PET) bottling material was assessed in twelve brands of bottled water purchased in Mexican supermarkets by atomic fluorescence spectrometry with a hydride generation system (HG-AFS). Dowex® 1X8-100 ion-exchange resin was used to preconcentrate trace amounts of Sb in water samples. Migration experiments from the PET bottle material were performed in water according to the following storage conditions: 1) temperature (25 and 75 °C), 2) pH (3 and 7) and 3) exposure time (5 and 15 days), using ultrapure water as a simulant for liquid foods. The test conditions were studied by a 2 3 factorial experimental design. The Sb concentration measured in the PET packaging materials varied between 73.0 and 111.3 mg/kg. The Sb concentration (0.28–2.30 μg/L) in all of the PET bottled drinking water samples examined at the initial stage of the study was below the maximum contaminant level of 5 μg/L prescribed by European Union (EU) regulations. The parameters studied (pH, temperature, and storage time) significantly affected the release of Sb, with temperature having the highest positive significant effect within the studied experimental domain. The highest Sb concentration leached from PET containers was in water samples at pH 7 stored at 75 °C for a period of 5 days. The extent of Sb leaching from the PET ingredients for different brands of drinking water can differ by as much as one order of magnitude in experiments conducted under the worst-case conditions. The chronic daily intake (CDI) caused by the release of Sb in one brand exceeded the Environmental Protection Agency (USEPA) regulated CDI value of 400 ng/kg/day, with values of 514.3 and 566.2 ng/kg/day for adults and children. Thus, the appropriate selection of the polymer used for the production of PET bottles seems to ensure low Sb levels in water samples. - Highlights: • The PET safety due to the release of Sb was evaluated in Mexican water PET

  8. An evaluation of the migration of antimony from polyethylene terephthalate (PET) plastic used for bottled drinking water

    Energy Technology Data Exchange (ETDEWEB)

    Chapa-Martínez, C.A.; Hinojosa-Reyes, L.; Hernández-Ramírez, A.; Ruiz-Ruiz, E.; Maya-Treviño, L.; Guzmán-Mar, J.L., E-mail: jorge.guzmanmr@uanl.edu.mx

    2016-09-15

    The leaching of antimony (Sb) from polyethylene terephthalate (PET) bottling material was assessed in twelve brands of bottled water purchased in Mexican supermarkets by atomic fluorescence spectrometry with a hydride generation system (HG-AFS). Dowex® 1X8-100 ion-exchange resin was used to preconcentrate trace amounts of Sb in water samples. Migration experiments from the PET bottle material were performed in water according to the following storage conditions: 1) temperature (25 and 75 °C), 2) pH (3 and 7) and 3) exposure time (5 and 15 days), using ultrapure water as a simulant for liquid foods. The test conditions were studied by a 2{sup 3} factorial experimental design. The Sb concentration measured in the PET packaging materials varied between 73.0 and 111.3 mg/kg. The Sb concentration (0.28–2.30 μg/L) in all of the PET bottled drinking water samples examined at the initial stage of the study was below the maximum contaminant level of 5 μg/L prescribed by European Union (EU) regulations. The parameters studied (pH, temperature, and storage time) significantly affected the release of Sb, with temperature having the highest positive significant effect within the studied experimental domain. The highest Sb concentration leached from PET containers was in water samples at pH 7 stored at 75 °C for a period of 5 days. The extent of Sb leaching from the PET ingredients for different brands of drinking water can differ by as much as one order of magnitude in experiments conducted under the worst-case conditions. The chronic daily intake (CDI) caused by the release of Sb in one brand exceeded the Environmental Protection Agency (USEPA) regulated CDI value of 400 ng/kg/day, with values of 514.3 and 566.2 ng/kg/day for adults and children. Thus, the appropriate selection of the polymer used for the production of PET bottles seems to ensure low Sb levels in water samples. - Highlights: • The PET safety due to the release of Sb was evaluated in Mexican water PET

  9. Investor's and procurement guide South Africa. Pt. 1. Heavy minerals, rare earth elements, antimony

    Energy Technology Data Exchange (ETDEWEB)

    Graupner, Torsten; Schwarz-Schampera, Ulrich [Bundesanstalt fuer Geowissenschaften und Rohstoffe (BGR), Berlin (Germany); Hammond, Napoleon Q.; Opperman, Rehan; Long' a Tongu, Elisa; Kenan, Abdul O.; Nondula, Unathi; Tsanwani, Matamba [Council for Geoscience (CGS), Pretoria (South Africa). Dept. of Mineral Resources Development; Liedke, Maren; Marbler, Herwig [Bundesanstalt fuer Geowissenschaften und Rohstoffe (BGR), Berlin (Germany). Deutsche Rohstoffagentur (DERA)

    2014-03-15

    This is the first part of the ''Investor's and Procurement Guide South Africa'', a handbook for investing and doing business in South Africa's mineral industry. It is anticipated that this publication will aid potential investors into considering South Africa as an investment destination, not only for raw materials, but also for related industries. This manual supplements the many publications available on the economic geology and mineral wealth in South Africa and has been designed to guide prospective and current investors, suppliers and mine equipment exporters through the process of doing business in Africa's biggest and dynamic economy. As well as detailing the mineral raw materials heavy minerals, rare-earth metals and antimony, the handbook provides a general introduction to South Africa and its infrastructure, the economical, political and judicial frame of the South African mining industry and an overview of the economic geology. South Africa has a long and complex geological history which dates back in excess of 3.6 billion years. The country has a vast mineral wealth, undoubtedly due to the fact that a significant proportion of the Archaean and younger rocks have been preserved. The mining of the enormous Witwatersrand gold deposits, commencing in 1886, has led to the establishment of South Africa's well-developed infrastructure and to the sustained growth of an industrial and service sector in the country. With the world's largest resources of PGMs, gold, chromite, vanadium and manganese and significant resources of iron, coal and numerous other minerals and metals, the minerals industry will continue to play a pivotal role in the growth of South Africa's economy in the foreseeable future. South Africa is one of the top destinations in Africa for foreign direct investments. South African headquartered companies have been major investors into foreign direct investments on the African continent in the past

  10. Dressings combined with injection of meglumine antimoniate in the treatment of cutaneous leishmaniasis: a randomized controlled clinical trial.

    Directory of Open Access Journals (Sweden)

    Alireza Khatami

    Full Text Available BACKGROUND: Cutaneous leishmaniasis (CL is a neglected infectious disease and a major health problem in several developing countries. Despite some reasonable explanation for their potential benefits, there is only trace evidence regarding the role of dressings in the treatment of CL. METHODS: This randomized, assessor-blind, controlled, clinical trial was conducted in an endemic area for CL caused by Leishmania major in Iran to assess the efficacy of administration of weekly intralesional meglumine antimoniate (i.l.MA either alone or combined with application of a silver or a non-silver polyester dressing on their lesions for 6 weeks. After screening of 241 patients with CL lesions, 83 eligible patients with 158 lesions were randomly allocated in three arms of the study. Eligibility criteria included parasitologically confirmed CL, age of 12 to 60 years; willingness to participate, duration of lesion<3 months, number of lesions<5, largest ulcer diameter<5 cm. Pregnant or lactating women were excluded. The primary outcome was absolute risk reduction (ARR based on the proportion of complete healing, which was defined as more than 75% reduction in the size of the lesion compared with baseline in each group at the termination of treatment and 1 month later. FINDINGS: ARR (95% Confidence Interval [CI] in i.l.MA versus i.l.MA+non-silver dressing groups was 5.98% (-7.07% to 20.25%, between i.l.MA versus i.l.MA+silver dressing groups was -0.23% (-13.53% to 14.82%, and between i.l.MA+non-silver dressing versus i.l.MA+silver dressing groups was -6.21%(-18.28% to 6.52% after 6 weeks of treatment. ARR (95% CI in i.l.MA versus i.l.MA+non-silver dressing groups was -2.22% (-22.12% to 18.10%, between i.l.MA versus i.l.MA+silver dressing groups was 3.64% (-15.36% to 22.82%, and between i.l.MA+non-silver dressing versus i.l.MA+silver dressing groups was 5.86% (-12.86% to 24.31% 1 month later. CONCLUSION: It could not be demonstrated that the efficacy of i

  11. Coupled S and Sr isotope evidences for elevated arsenic concentrations in groundwater from the world's largest antimony mine, Central China

    Science.gov (United States)

    Wen, Bing; Zhou, Aiguo; Zhou, Jianwei; Liu, Cunfu; Huang, Yuliu; Li, Ligang

    2018-02-01

    The Xikuangshan(XKS) mine, the world's largest antimony mine, was chosen for a detailed arsenic hydrogeochemical study because of the elevated arsenic in bedrock aquifers used by local residents. Hydrochemical data, δ34S values of dissolved SO42- and 87Sr/86Sr ratios have been analyzed to identify the predominant geochemical processes that control the arsenic mobilization within the aquifers. Groundwater samples can be divided into three major types: low arsenic groundwater (0-50 μg/L), high arsenic groundwater (50-1000 μg/L) and anomalous high arsenic groundwater (>1000 μg/L). Arsenic occurs under oxidizing conditions at the XKS Sb mine as the HAsO42- anion. The Ca/Na ratio correlates significantly with HCO3-/Na and Sr/Na ratios, indicating that carbonate dissolution and silicate weathering are the dominant processes controlling groundwater hydrochemistry. The δ34S values of the groundwater indicate that dissolved SO42- in groundwater is mainly sourced from the oxidation of sulfide minerals, and elevated As concentrations in groundwater are influenced by the mixing of mine water and surface water. Furthermore, the δ34S values are not correlated with dissolved As concentrations and Fe concentrations, suggesting that the reduction dissolution of Fe(III) hydroxides is not the dominant process controlling As mobilization. The 87Sr/86Sr ratios imply that elevated As concentrations in groundwater are primarily derived from the interaction with the stibnite and silicified limestone. More specifically, the excess-Na ion, the feature of Ca/Na ratio, and the spatial association of elevated As concentrations in groundwater collectively suggest that high and anomalous high arsenic groundwater are associated with smelting slags and, in particular, the arsenic alkali residue. In general, the hydrochemistry analysis, especially the S and Sr isotope evidences elucidate that elevated As concentrations and As mobilization are influenced by several geochemical processes

  12. Investor's and procurement guide South Africa. Pt. 1. Heavy minerals, rare earth elements, antimony

    International Nuclear Information System (INIS)

    Graupner, Torsten; Schwarz-Schampera, Ulrich; Hammond, Napoleon Q.; Opperman, Rehan; Long'a Tongu, Elisa; Kenan, Abdul O.; Nondula, Unathi; Tsanwani, Matamba

    2014-01-01

    This is the first part of the ''Investor's and Procurement Guide South Africa'', a handbook for investing and doing business in South Africa's mineral industry. It is anticipated that this publication will aid potential investors into considering South Africa as an investment destination, not only for raw materials, but also for related industries. This manual supplements the many publications available on the economic geology and mineral wealth in South Africa and has been designed to guide prospective and current investors, suppliers and mine equipment exporters through the process of doing business in Africa's biggest and dynamic economy. As well as detailing the mineral raw materials heavy minerals, rare-earth metals and antimony, the handbook provides a general introduction to South Africa and its infrastructure, the economical, political and judicial frame of the South African mining industry and an overview of the economic geology. South Africa has a long and complex geological history which dates back in excess of 3.6 billion years. The country has a vast mineral wealth, undoubtedly due to the fact that a significant proportion of the Archaean and younger rocks have been preserved. The mining of the enormous Witwatersrand gold deposits, commencing in 1886, has led to the establishment of South Africa's well-developed infrastructure and to the sustained growth of an industrial and service sector in the country. With the world's largest resources of PGMs, gold, chromite, vanadium and manganese and significant resources of iron, coal and numerous other minerals and metals, the minerals industry will continue to play a pivotal role in the growth of South Africa's economy in the foreseeable future. South Africa is one of the top destinations in Africa for foreign direct investments. South African headquartered companies have been major investors into foreign direct investments on the African continent in the past

  13. Arsenic and Antimony Removal from Drinking Water by Point-of-Entry Reverse Osmosis Coupled with Dual Plumbing Distribution - U.S. EPA Demonstration Project at Carmel Elementary School in Carmel, ME -Final Performance Evaluation Report

    Science.gov (United States)

    This report documents the activities performed for and the results obtained from the arsenic and antimony removal treatment technology demonstration project at the Carmel Elementary School (CES) in Carmel, ME. An innovative approach of employing point of entry (POE) reverse osmo...

  14. Room temperature electrodeposition of aluminum antimonide compound semiconductor

    Energy Technology Data Exchange (ETDEWEB)

    Gandhi, T.; Raja, K.S. [Metallurgical and Materials Engineering, University of Nevada, Mail Stop 388, Reno, NV 89557 (United States); Misra, M. [Metallurgical and Materials Engineering, University of Nevada, Mail Stop 388, Reno, NV 89557 (United States)], E-mail: misra@unr.edu

    2008-10-15

    AlSb is a group III-V compound semiconductor material that is conventionally grown by high temperature processes such as Czochralski and Bridgman methods. Development of a method to synthesize AlSb at room temperature will be more economical to help modulate the electronic properties. In this investigation, a pulsed potential electrodeposition method using a room temperature molten salt system (aluminum trichloride, AlCl{sub 3}/1-methyl-3-ethylimidazolium chloride, EMIC) with an addition of SbCl{sub 3} is discussed. The potential pulse parameters were established by carrying out cyclic voltammetry at different concentrations of SbCl{sub 3} and with varying molar ratios of AlCl{sub 3}/EMIC. Stoichiometric AlSb deposits were obtained from an acidic AlCl{sub 3}/EMIC (1.5:1 molar ratio) melt containing 4 x 10{sup -3} mol/l of SbCl{sub 3} onto an ordered TiO{sub 2} nanotubular template. The AlSb compound was predominantly amorphous in as-deposited condition and annealing at 350 deg. C for 2 h in argon transformed into crystalline phase. The AlSb deposit showed a high resistivity in the order of 10{sup 9} {omega}-cm and a defect concentration of 10{sup 16} cm{sup -3} which was attributed to presence of carbon. The deposits obtained from a basic melt (0.67:1 molar ratio of AlCl{sub 3}/EMIC) were enriched with antimony.

  15. Anti-leishmanial activity of heteroleptic organometallic Sb(v) compounds.

    Science.gov (United States)

    Ali, Muhammad Irshad; Rauf, Muhammad Khawar; Badshah, Amin; Kumar, Ish; Forsyth, Craig M; Junk, Peter C; Kedzierski, Lukasz; Andrews, Philip C

    2013-12-28

    In seeking new drugs for the treatment of the parasitic disease Leishmaniasis, an extensive range of organometallic antimony(v) dicarboxylates of the form [SbR3(O2CR')2] have been synthesised, characterised and evaluated. The organometallic moieties (R) in the complexes vary in being Ph, tolyl (o, m or p), or benzyl. The carboxylates are predominantly substituted benzoates with some compounds incorporating acetato or cinnamato ligands. The crystal structures of [Sb(p-Tol)3(O2CC6H2-3,4,5-(OMe)3)2]·0.5PhMe and [SbPh3(m-CH3C6H4CH2CO2)2] were determined and shown to adopt a typical trigonal pyramidal geometry, being monomeric with a five coordinate Sb centre. In total, the biological activity of 26 Sb(v) compounds was assessed against the Leishmania major parasite, and also human fibroblast skin cells to give a measure of general toxicity. Of these, 11 compounds (predominantly substituted benzoates with m- or p-tolyl ligands) proved to be highly effective against the parasite amastigotes at concentrations of 0.5-3.5 μM, while being non-toxic towards the mammalian cells at levels below 25 μM, making them highly promising drug candidates.

  16. Structural and optical properties of antimony-germanate-borate glass and glass fiber co-doped Eu3+ and Ag nanoparticles.

    Science.gov (United States)

    Zmojda, Jacek; Kochanowicz, Marcin; Miluski, Piotr; Baranowska, Agata; Pisarski, Wojciech A; Pisarska, Joanna; Jadach, Renata; Sitarz, Maciej; Dorosz, Dominik

    2018-04-25

    In the paper analysis of structural and luminescent properties of antimony-germanate-borate glasses and glass fiber co-doped with 0.6AgNO 3 /0.2Eu 2 O 3 are presented. Heat treatment of the fabricated glass and optical fiber (400 °C, 12 h) enabled to obtain Ag nanoparticles (NPs) with average size 30-50 nm on their surface. It has been proofed that silver ions migrate to the glass surface, where they are reduced to Ag 0 nanoparticles. Simultaneously, FTIR analysis showed that heat treatment of the glass and optical fiber increases the local symmetry of the Eu 3+ site. Copyright © 2018. Published by Elsevier B.V.

  17. The influence of Ag content and annealing time on structural and optical properties of SGS antimony-germanate glass doped with Er3+ ions

    Science.gov (United States)

    Zmojda, J.; Kochanowicz, M.; Miluski, P.; Baranowska, A.; Basa, A.; Jadach, R.; Sitarz, M.; Dorosz, D.

    2018-05-01

    A series of erbium doped SGS antimony-germanate glass embedding silver (Ag0) nanoparticles have been synthesized by a one-step melt-quench thermochemical reduction technique. The effect of NPs concentration and annealing time on the structural and photoluminescent (PL) properties were investigated. The Raman spectra as a function of temperature measured in-situ allow to determine the structural changes in vicinity of Ag+ ions and confirmed thermochemical reduction of Ag+ ions by Sb3+ ions. The surface plasmon resonance absorption band was evidenced near 450 nm. The impact of local field effect generated by Ag0 nanoparticles (NPs) and energy transfer from surface of silver NPs to trivalent erbium ions on near-infrared and up-conversion luminescence was described in terms of enhancement and quench phenomena.

  18. Influence of mycorhization and soil organic matters on lead and antimony transfers to vegetables cultivated in urban gardens: environmental and sanitary consequences

    Science.gov (United States)

    Pierart, Antoine; Braud, Armelle; Lebeau, Thierry; Séjalon-Delmas, Nathalie; Dumat, Camille

    2014-05-01

    The European Environment Agency estimates that c.a. 250 000 sites required clean up and that about 100 000 ha could have been contaminated by metals in Europe. Numerous remediation techniques have been therefore tested and phytoremediation appears as a sustainable and low cost in situ technique particularly for large-scale remediation of polluted arable soils. Arbuscular Mycorrhizal Fungi (AMF) are already used in phytoextraction or phytostabilisation of many metal(loid)s (GU ET AL., 2013, SHARMA AND SHARMA, 2013). However, while plant inoculation with AMF will mostly result of an increase of the plant biomass, the response for lead accumulation in shoots is contrasted (LEBEAU ET AL., 2008). Furthermore, nothing is actually known for Sb transfer to plants phytoremediation-assisted AMF. Yet recently, many researches concern the accumulation of Sb in the environment, its (eco)toxicity and the risk of bioaccumulation in vegetables (FENG ET AL., 2013), especially in some China areas where Sb mining activities have widely contaminated arable lands (WU ET AL., 2011). Our research project, which is part of a national program for urban gardens (JASSUR, http://www.agence-nationale-recherche.fr), focused on polluted soils in associative urban gardens with both geogenic and anthropogenic origins for Pb and Sb. The impact of Pb and Sb on AMF density and diversity was studied using morphological and biomolecular approaches. The role of AMF symbiosis with Lettuce (Lactuca sativa L.) on Pb and Sb compartmentalization, speciation and phytoavailability was investigated. The influence of soil organic matters on these processes was examined. Eventually, the part of metal(loid)s available for humans in case of ingestion of lettuces unfit for human consumption (FOUCAULT ET AL., 2013; XIONG ET AL., 2013) will be assessed in relation with the influence of AMF symbiosis and organic matter. Key Words: Mycorrhiza, Antimony, Compartmentation, Speciation, Edible Plants, Urban Agriculture

  19. Post-CMOS FinFET integration of bismuth telluride and antimony telluride thin-film-based thermoelectric devices on SoI substrate

    KAUST Repository

    Aktakka, Ethem Erkan

    2013-10-01

    This letter reports, for the first time, heterogeneous integration of bismuth telluride (Bi2Te3) and antimony telluride (Sb 2Te3) thin-film-based thermoelectric ffect transistors) via a characterized TE-film coevaporationand shadow-mask patterning process using predeposition surface treatment methods for reduced TE-metal contact resistance. As a demonstration vehicle, a 2 × 2 mm2-sized integrated planar thermoelectric generator (TEG) is shown to harvest 0.7 μ W from 21-K temperature gradient. Transistor performance showed no significant change upon post-CMOS TEG integration, indicating, for the first time, the CMOS compatibility of the Bi2Te3 and Sb2Te3 thin films, which could be leveraged for realization of high-performance integrated micro-TE harvesters and coolers. © 2013 IEEE.

  20. Investigation of strontium and uranium sorption onto zirconium-antimony oxide/polyacrylonitrile (Zr-Sb oxide/PAN) composite using experimental design.

    Science.gov (United States)

    Cakir, Pelin; Inan, Suleyman; Altas, Yuksel

    2014-04-30

    A study on the sorption of strontium (Sr(2+)) and uranium (UO2(2+)) onto zirconium-antimony oxide/PAN (Zr-Sb oxide/PAN) composite was conducted. The zirconium-antimony oxide was synthesized and was then turned into composite spheres by mixing it with polyacrylonitrile (PAN). The single and combined effects of independent variables such as initial pH, temperature, initial ion concentration and contact time on the sorption of Sr(2+) and UO2(2+) were separately analyzed using response surface methodology (RSM). Central composite design (CCD) was separately employed for Sr(2+) and UO2(2+) sorption. Analysis of variance (ANOVA) revealed that all of the single effects found statistically significant on the sorption of Sr(2+) and UO2(2+). Probability F-values (F=2.45 × 10(-08) and F=9.63 × 10(-12) for Sr(2+) and UO2(2+), respectively) and correlation coefficients (R(2)=0.96 for Sr(2+) and R(2)=0.98 for UO2(2+)) indicate that both models fit the experimental data well. At optimum sorption conditions Sr(2+) and UO2(2+) sorption capacities of the composite were found as 39.78 and 60.66 mg/g, respectively. Sorption isotherm data pointed out that Langmuir model is more suitable for the Sr(2+) sorption, whereas the sorption of UO2(2+) was correlated well with the Langmuir and Freundlich models. Thermodynamic parameters such as ΔH°, ΔS° and ΔG° indicate that Sr(2+) and UO2(2+) sorption processes are endothermic and spontaneous. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. The occurrence and distribution of high-arsenic, selenium, tin and antimony in bottom sediments of Burullus lagoon and its effects on human health, Egypt

    Science.gov (United States)

    El-Badry, Abd El-Monsef Ahmed; Khalifa, Moataz M.

    2017-12-01

    Burullus lagoon is one of four natural water bodies known as northern Egyptian delta lakes. The lagoon extended maximum long of 53 km long and maximum width 13 km with an area about 420 km2. The pollution of bottom sediment of the Burullus lagoon is indicative of both water and food web quality in general. A few research were carried out related to study of arsenic, selenium, tin and antimony. The main objective of this study is assessment of environmental effects of arsenic, selenium, tin and antimony metals, twenty-one samples were collect from bottom sediments sample among sites covering the Burullus Lagoon during summer 2014, and analyzed by using simultaneous inductively coupled plasma emission spectrometer. The contamination with these metals was evaluate by applying index of contamination factor (CF) and geoaccumulation (Igeo). The relative order of abundance of the potentially toxic metals in the lagoon's sediment is Se > Sn > Sb > As The territory around inlet and southeastern drain show considerable pollution by the studied toxic metals. The main reason for such pollution resulting from industrial activities and agricultural drains. The disregards of the anthropogenic activities are the main reason of pollution in the studied lagoon. Construction of special units for treatment and purification of all types of drainage and wastewater (agricultural, industrial). Successive analysis of lake water to assess the amount of pollutants to make suitable decisions. Take an action to prohibit throwing of wastes in the lagoon. Consumption of the lake water for agricultural and industrial must be under control in order to decrease water pollution.

  2. Post-traumatic avascular necrosis of the femoral head predicted by preoperative technetium-99m antimony-colloid scan: an experimental and clinical study

    International Nuclear Information System (INIS)

    Turner, J.H.

    1983-01-01

    Technetium-99m antimony colloid was used to visualize the bone marrow of the head of the femur within twenty-four hours after interruption of the blood supply by subcapital osteotomy and section of the ligamentum teres in thirteen rabbits and within twenty-four hours after a subcapital fracture in thirty patients. Of the rabbits, all showed loss of marrow radioactivity over the affected femoral head. Bone-imaging with technetium-99m methylene diphosphonate, in contrast, failed to demonstrate any abnormality in the avascular head of the femur for as long as forty-eight hours after osteotomy. This difference between the marrow scan and the bone scan was attributed to earlier loss of function in the marrow cells than in the osteocytes. The thirty patients who had a preoperative scan within twenty-four hours after sustaining a subcapital fracture were treated by internal fixation with a Richards screw and plate and were followed for as long as two years, or until the patient died or radiographs showed evidence of avascular necrosis. The preoperative technetium-99m antimony-colloid activity in the head of the fractured femur was normal in sixteen patients and absent in fourteen; two of the fourteen had no activity in either hip, which precluded assessment of the fractured hip in these patients. In fifteen of the sixteen hips, preservation of the uptake in the marrow of the head of the fractured femur preoperatively predicted normal healing. Late segmental collapse developed in the remaining hip. In eleven of the twelve patients who had loss of marrow activity in the femoral head preoperatively, avascular necrosis developed within two years

  3. Association of Liposome-Encapsulated Trivalent Antimonial with Ascorbic Acid: An Effective and Safe Strategy in the Treatment of Experimental Visceral Leishmaniasis

    Science.gov (United States)

    Castro, Renata A. O.; Silva-Barcellos, Neila M.; Licio, Carolina S. A.; Souza, Janine B.; Souza-Testasicca, Míriam C.; Ferreira, Flávia M.; Batista, Mauricio A.; Silveira-Lemos, Denise; Moura, Sandra L.; Frézard, Frédéric; Rezende, Simone A.

    2014-01-01

    Background: Visceral leishmaniasis (VL) is a chronic debilitating disease endemic in tropical and subtropical areas, caused by protozoan parasites of the genus Leishmania. Annually, it is estimated the occurrence of 0.2 to 0.4 million new cases of the disease worldwide. Considering the lack of an effective vaccine the afflicted population must rely on both, an accurate diagnosis and successful treatment to combat the disease. Here we propose to evaluate the efficacy of trivalent antimonial encapsulated in conventional liposomes, in association with ascorbic acid, by monitoring its toxicity and efficacy in BALB/c mice infected with Leishmania infantum. Methodology/Principal Findings: Infected mice were subjected to single-dose treatments consisting in the administration of either free or liposome-encapsulated trivalent antimony (SbIII), in association or not with ascorbic acid. Parasite burden was assessed in the liver, spleen and bone marrow using the serial limiting dilution technique. After treatment, tissue alterations were examined by histopathology of liver, heart and kidney and confirmed by serum levels of classic biomarkers. The phenotypic profile of splenocytes was also investigated by flow cytometry. Treatment with liposome-encapsulated SbIII significantly reduced the parasite burden in the liver, spleen and bone marrow. Co-administration of ascorbic acid, with either free SbIII or its liposomal form, did not interfere with its leishmanicidal activity and promoted reduced toxicity particularly to the kidney and liver tissues. Conclusions/Significance: Among the evaluated posological regimens treatment of L. infantum-infected mice with liposomal SbIII, in association with ascorbic acid, represented the best alternative as judged by its high leishmanicidal activity and absence of detectable toxic effects. Of particular importance, reduction of parasite burden in the bone marrow attested to the ability of SbIII-carrying liposomes to efficiently reach this

  4. Coordination Compounds in Biology

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 6. Coordination Compounds in Biology - The Chemistry of Vitamin B12 and Model Compounds. K Hussian Reddy. General Article Volume 4 Issue 6 June 1999 pp 67-77 ...

  5. Stable isotopes labelled compounds

    International Nuclear Information System (INIS)

    1982-09-01

    The catalogue on stable isotopes labelled compounds offers deuterium, nitrogen-15, and multiply labelled compounds. It includes: (1) conditions of sale and delivery, (2) the application of stable isotopes, (3) technical information, (4) product specifications, and (5) the complete delivery programme

  6. MTF of compound eye.

    Science.gov (United States)

    Fallah, Hamid Reza; Karimzadeh, Ayatollah

    2010-06-07

    Compound eye is a new field of research about miniaturizing imaging systems. We for the first time introduce a dual compound eye that contains three micro lens arrays with aspheric surfaces. The designed dual compound eye in one state is a superposition system in which each channel images all of field of view of the system. With adding a field stop we have decreased the stray light. MTF of ideal superposition compound eye calculated. Also with changing field stop the system is converted to an apposition compound eye in which each channel images only a part of total field of view and so the field of view is larger than that of superposition type.

  7. Compounding around the world.

    Science.gov (United States)

    Vail, Jane

    2008-01-01

    Pharmaceutical compounding is universal in its prevalence. Variations in disease patterns, culture, and tradition; the role of government in health care; and the availability of essential equipment and required agents shape a compounding profile unique to each country worldwide. In the following reflections, pharmacists form Argentina, Belgium, Colombia, Germany, Puerto Rico, Spain, and the United States describe their experiences in the compounding setting unique to their practice and their nation. The unifying theme in their comments is the dedication of each contributor to enabling recovery and ensuring the good health of his or her clients.

  8. Compound Semiconductor Radiation Detectors

    CERN Document Server

    Owens, Alan

    2012-01-01

    Although elemental semiconductors such as silicon and germanium are standard for energy dispersive spectroscopy in the laboratory, their use for an increasing range of applications is becoming marginalized by their physical limitations, namely the need for ancillary cooling, their modest stopping powers, and radiation intolerance. Compound semiconductors, on the other hand, encompass such a wide range of physical and electronic properties that they have become viable competitors in a number of applications. Compound Semiconductor Radiation Detectors is a consolidated source of information on all aspects of the use of compound semiconductors for radiation detection and measurement. Serious Competitors to Germanium and Silicon Radiation Detectors Wide-gap compound semiconductors offer the ability to operate in a range of hostile thermal and radiation environments while still maintaining sub-keV spectral resolution at X-ray wavelengths. Narrow-gap materials offer the potential of exceeding the spectral resolutio...

  9. MEA 86 Compound data

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data file contains the full raw parameter data for the 86 compounds tested in the developmental MEA assay, as well as Area Under the Curve (AUC) calculations...

  10. Hexavalent Chromium Compounds

    Science.gov (United States)

    Learn about chromium, exposure to which can increase your risk of lung cancer and cancer of the paranasal sinuses and nasal cavity. Hexavalent chromium compounds have been used as corrosion inhibitors in a wide variety of products and processes.

  11. Compound composite odontoma.

    Science.gov (United States)

    Girish, G; Bavle, Radhika M; Singh, Manish Kumar; Prasad, Sahana N

    2016-01-01

    The term odontoma has been used as a descriptor for any tumor of odontogenic origin. It is a growth in which both epithelial and mesenchymal cells exhibits complete differentiation. Odontomas are considered as hamartomas rather than true neoplasm. They are usually discovered on routine radiographic examination. Odontomas, according to the World Health Organization, are classified into complex odontoma and compound odontomas. The present paper reports a case of compound composite odontomas.

  12. Endocrine disrupting compounds

    DEFF Research Database (Denmark)

    Bøgh, I B; Christensen, P; Dantzer, V

    2001-01-01

    processes, and exposure during critical periods of prenatal development might affect reproductive performance over several generations. Alkylphenols and their metabolites are lipophilic substances exerting apparent estrogenic action in in vitro and in vivo testing systems. With the widespread industrial use...... or embryo models for the evaluation of possible consequences of human exposure to endocrine disrupting compounds is discussed. Furthermore, possible consequences of exposure to endocrine disrupting compounds for the embryo transfer industry are addressed....

  13. Phenolic compounds in flaxseed

    OpenAIRE

    Johnsson, Pernilla

    2004-01-01

    The dietary lignan secoisolariciresinol diglucoside (SDG), present in high concentrations in flaxseed, and its metabolites enterolactone and enterodiol are thought to decrease the risk of hormone dependent cancers, cardiovascular disease and other “welfare” diseases. Flaxseed also contains other biologically active phenolic compounds, such as phenolic acids. The understanding of the nature of these compounds is crucial for their possible exploitation in drugs and functional foods. Until the m...

  14. Successful therapeutic response of resistant cases of mucocutaneous leishmaniasis to a very low dose of antimony Resposta terapêutica bem sucedida de casos resistentes de leishmaniose mucocutânea a doses muito baixas de antimônio

    Directory of Open Access Journals (Sweden)

    Manoel Paes de Oliveira-Neto

    2006-08-01

    Full Text Available Two mucocutaneous leishmaniasis cases resistant to therapy are reported here. After the failure of initial therapies (antimony, amphotericin B and/or pentamidine patients received a low-dose schedule: one ampoule of meglumine antimoniate (405mg of pentavalent antimony [Sb v] by intramuscular injection, three times a week until complete healing of the lesions. One patient was cured with a total of 30 ampoules in 10 weeks and the other received 36 ampoules in 12 weeks. Both remain clinically cured after one year of follow-up.São relatados dois casos de leishmaniose mucocutânea resistentes ao tratamento. Depois das terapêuticas iniciais (antimônio, anfotericina B e/ou pentamidina, os pacientes receberam um esquema alternativo: uma ampola de antimoniato de meglumina (405mg de antimônio pentavalnte [Sb v] por via intramuscular, três vezes por semana até a cura completa das lesões. Um paciente recebeu um total de 30 ampolas durante 10 semanas e o outro, 36 ampolas durante 12 semanas. Ambos permanecem clinicamente curados até um ano após o tratamento.

  15. Fractionation and redox speciation of antimony in agricultural soils by hydride generation--atomic fluorescence spectrometry and stability of Sb(III) and Sb(V) during extraction with different extractant solutions.

    Science.gov (United States)

    Fuentes, Edwar; Pinochet, Hugo; Potin-Gautier, Martine; De Graegori, Ida

    2004-01-01

    This stability of Sb(III) and Sb(V) species was studied during single extraction from soils by water. EDTA, diluted H2SO4 and H3PO4, and oxalic acid/oxalate solutions, with and without ascorbic acid, were used as stabilizing reagent of both Sb species. Antimony redox speciation in soil extracts was performed by selective hydride generation-atomic fluorescence spectrometry. Simulated extraction procedures (without soil) showed that, except in oxalate medium, Sb(III) was oxidized to Sb(V), and this reaction was avoided with ascorbic acid. Recovery studies from a spiked agricultural soil showed that no oxidation but sorption of Sb(III) occurred during the extraction process in water and H2SO4 medium, and quantitative oxidation in EDTA and oxalate medium. With ascorbic acid, this oxidation was totally avoided in EDTA and partially avoided in oxalate solution. A new sequential extraction procedure was proposed and applied to the fractionation and redox speciation of antimony in agricultural soils, using EDTA + ascorbic acid, pH 7 (available under complexing and moderately reducible conditions); oxalic acid/oxalate + ascorbic acid (extractable in reducible conditions) and HNO3 + HCl + HF (residual fraction). The proposed extraction scheme can provide information about the availability and mobility of antimony redox species in agricultural soils.

  16. Atomic layer deposition of metal tellurides and selenides using alkylsilyl compounds of tellurium and selenium.

    Science.gov (United States)

    Pore, Viljami; Hatanpää, Timo; Ritala, Mikko; Leskelä, Markku

    2009-03-18

    Atomic layer deposition (ALD) of metal selenide and telluride thin films has been limited because of a lack of precursors that would at the same time be safe and exhibit high reactivity as required in ALD. Yet there are many important metal selenide and telluride thin film materials whose deposition by ALD might be beneficial, for example, CuInSe2 for solar cells and Ge2Sb2Te5 for phase-change random-access memories. Especially in the latter case highly conformal deposition offered by ALD is essential for high storage density. By now, ALD of germanium antimony telluride (GST) has been attempted only using plasma-assisted processes owing to the lack of appropriate tellurium precursors. In this paper we make a breakthrough in the development of new ALD precursors for tellurium and selenium. Compounds with a general formula (R3Si)2Te and (R3Si)2Se react with various metal halides forming the corresponding metal tellurides and selenides. As an example, we show that Sb2Te3, GeTe, and GST films can be deposited by ALD using (Et3Si)2Te, SbCl3, and GeCl2 x C4H8O2 compounds as precursors. All three precursors exhibit a typical saturative ALD growth behavior and GST films prepared at 90 degrees C show excellent conformality on a high aspect-ratio trench structure.

  17. A study on antimony determination in environmental samples by neutron activation analysis: validation of the methodology and determination of the uncertainty of the measurement

    International Nuclear Information System (INIS)

    Matsubara, Tassiane Cristina Martins

    2011-01-01

    Antimony is an element found in low concentrations in the environment. However, its determination has attracted great interest due to the knowledge of its toxicity and increasing application in industry. The determination of antimony has been a challenge for researchers since this element is found in low concentrations which make its analysis a difficult task. Therefore, although neutron activation analysis (NAA) is an appropriate method for the determination of various elements in different types of matrix, in the case of Sb its analysis presents some difficulties, mainly due to spectral interferences. The objective of this research was to validate the NAA method for Sb determination in environmental samples. To establish appropriate conditions for Sb determinations, preliminary assays were carried out for further analysis of certified reference materials (CRM). The experimental procedure was to irradiate samples with a synthetic Sb standard for a period of 8 or 16 hours in the IEA-R1 nuclear research reactor, followed by gamma ray spectrometry. The quantification of Sb was performed by measuring the radioactive isotopes of 122 Sb and '1 24 Sb. The results of preliminary assays indicated the presence of Sb in Whatman no 40 filter paper used in the preparation of the synthetic standard, but at very low concentrations, which could be considered negligible. In the case of the plastic material used in bags for the sample irradiation, it should be chosen carefully, because depending on the thickness, they may contain Sb. The analyses of the stability of the diluted Sb standard solution showed no change in the Sb concentration within eight months after its preparation. Results obtained in the analysis of certified reference materials indicated the interference of 76 As and also of 134 Cs and 152 Eu in the Sb determinations by measuring '1 22 Sb, due to the proximity of the gamma ray energies. The high activity of '2 4 Na can also mask the peak of 122 Sb hindering its

  18. Synthesis of Ce(III)-doped Fe{sub 3}O{sub 4} magnetic particles for efficient removal of antimony from aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Zenglu; Joshi, Tista Prasai [Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Liu, Ruiping, E-mail: liuruiping@rcees.ac.cn [Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Liu, Huijuan [University of Chinese Academy of Sciences, Beijing 100049 (China); State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085 (China); Qu, Jiuhui [Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085 (China); University of Chinese Academy of Sciences, Beijing 100049 (China)

    2017-05-05

    Highlights: • Doping of Ce into Fe{sub 3}O{sub 4} was achieved based on a facile solvothermal method. • After doping, the removal capacity was increased by 5 times for “Sb(V)” and 2 times for “Sb(III)”. • Decreasing pH improved adsorption of Sb(V) but decreased adsorption of Sb(III). • Antimony sorption mechanisms on Ce-doped Fe{sub 3}O{sub 4} were illustrated. - Abstract: Aqueous antimony (Sb) pollution from human activity is of great concern in drinking water due to its adverse health effect. Magnetic Fe{sub 3}O{sub 4} particles, with high separation ability from solution, have been considered as a low-cost Sb adsorbent for contaminants. However, the limited adsorption capacity has restricted its practical application. In this study, a solvothermal approach was developed for doping Ce(III) into Fe{sub 3}O{sub 4}, thereby increasing the adsorption efficacy for both Sb(III) and Sb(V). In contrast to un-doped Fe{sub 3}O{sub 4}, the adsorption capacity towards Sb(III) and Sb(V) in Ce-doped materials increased from 111.4 to 224.2 mg/g and from 37.2 to 188.1 mg/g at neutral pH, respectively. Based on the combined results of XPS, XRD, and FTIR, it confirmed that Ce atom successfully doped into the Fe{sub 3}O{sub 4} structure, resulting in the decreased particle size, increased the surface area, and isoelectric point. Furthermore, the vibrating sample magnetometer (VSM) results showed that the Ce doping process had some side effects on the primitive magnetic property, but remaining the high separation potential during water treatment. According to the high removal efficiency and magnetic property, the Ce-doped Fe{sub 3}O{sub 4} of great simplicity should be a promising adsorbent for aqueous Sb removal.

  19. Fluorine-18 labelled compounds

    International Nuclear Information System (INIS)

    Kleijn, J.P. de

    1978-01-01

    The work presented in this thesis deals with the problems involved in the adaption of reactor-produced fluorine-18 to the synthesis of 18 F-labelled organic fluorine compounds. Several 18 F-labelling reagents were prepared and successfully applied. The limitations to the synthetic possibilities of reactor-produced fluoride- 18 become manifest in the last part of the thesis. An application to the synthesis of labelled aliphatic fluoro amino acids has appeared to be unsuccessful as yet, although some other synthetic approaches can be indicated. Seven journal articles (for which see the availability note) are used to compose the four chapters and three appendices. The connecting text gives a survey of known 18 F-compounds and methods for preparing such compounds. (Auth.)

  20. Medicinal gold compounds

    International Nuclear Information System (INIS)

    Parish, R.V.; Cottrill, S.M.

    1987-01-01

    A major use of gold compounds in the pharmaceutical industry is for anti-arthritic agents. The disease itself is not understood and little is known about the way in which the drugs act, but detailed pictures of the distribution of gold in the body are available, and some of the relevant biochemistry is beginning to emerge. The purpose of this article is to give a survey of the types of compounds presently employed in medicine, of the distribution of gold in the body which results from their use, and of some relevant chemistry. Emphasis is placed on results obtained in the last few years

  1. Compound semiconductor device physics

    CERN Document Server

    Tiwari, Sandip

    2013-01-01

    This book provides one of the most rigorous treatments of compound semiconductor device physics yet published. A complete understanding of modern devices requires a working knowledge of low-dimensional physics, the use of statistical methods, and the use of one-, two-, and three-dimensional analytical and numerical analysis techniques. With its systematic and detailed**discussion of these topics, this book is ideal for both the researcher and the student. Although the emphasis of this text is on compound semiconductor devices, many of the principles discussed will also be useful to those inter

  2. Coordination Compounds in Biology

    Indian Academy of Sciences (India)

    Coordination Compounds in Biology equatorial ligand, there are two axial ligands in most B. 12 derivatives. Derivatives of B12. The various derivatives of B. 12 result most commonly from changes in the axial ligands bound to cobalt. Often it is convenient to draw a greatly abbreviated structure for a B. 12 molecule using a ...

  3. Polymeric coordination compounds

    Indian Academy of Sciences (India)

    Administrator

    Metal coordination polymers with one- and two-dimensional structures are of current interest due to their possible relevance to material science 1. In continuation of our previous studies 2,3, several new polymeric compounds are reported here. Among the complexes of silver with aminomethyl pyridine (amp) ...

  4. NATURAL POLYACETYLENE COMPOUNDS

    Directory of Open Access Journals (Sweden)

    A. M. Nasukhova

    2014-01-01

    Full Text Available In article the review of the initial stage of researches of natural polyacetylene compounds is resulted. The high reactionary ability leading to fast oxidation and degradation of these compounds, especially at influence of Uf-light, oxygen of air, pH and other factors, has caused the serious difficulties connected with an establishment of structure and studying of their physical and chemical properties. Therefore the greatest quantity of works of this stage is connected with studying of essential oils of plants from families Apiaceae, Araliaceae, Asteraceae, Campanulaceae, Olacaceae, Pittosporaceae and Santalaceae where have been found out, basically, diacetylene compounds. About development of physical and chemical methods of the analysis of possibility of similar researches have considerably extended. More than 2000 polyacetylenes are known today, from them more than 1100 are found out in plants fam. Asteraceae. Revolution in the field of molecular biology has allowed to study processes of biosynthesis of these compounds intensively.

  5. Phosphorus-nitrogen compounds

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 120; Issue 4. Phosphorus-nitrogen compounds: Part 15. Synthesis, anisochronism and the relationship between crystallographic and spectral data of monotopic spiro-crypta phosphazenes. Nuran Asmafi̇li̇z Eli̇f Ece İl Ter Zeynel Kiliç Tuncer Hökelek Ertan Şahin.

  6. Toxicology of perfluorinated compounds

    Energy Technology Data Exchange (ETDEWEB)

    Stahl, Thorsten [Hessian State Laboratory, Wiesbaden (Germany); Mattern, Daniela; Brunn, Hubertus [Hessian State Laboratory, Giessen (Germany)

    2011-12-15

    Perfluorinated compounds [PFCs] have found a wide use in industrial products and processes and in a vast array of consumer products. PFCs are molecules made up of carbon chains to which fluorine atoms are bound. Due to the strength of the carbon/fluorine bond, the molecules are chemically very stable and are highly resistant to biological degradation; therefore, they belong to a class of compounds that tend to persist in the environment. These compounds can bioaccumulate and also undergo biomagnification. Within the class of PFC chemicals, perfluorooctanoic acid and perfluorosulphonic acid are generally considered reference substances. Meanwhile, PFCs can be detected almost ubiquitously, e.g., in water, plants, different kinds of foodstuffs, in animals such as fish, birds, in mammals, as well as in human breast milk and blood. PFCs are proposed as a new class of 'persistent organic pollutants'. Numerous publications allude to the negative effects of PFCs on human health. The following review describes both external and internal exposures to PFCs, the toxicokinetics (uptake, distribution, metabolism, excretion), and the toxicodynamics (acute toxicity, subacute and subchronic toxicities, chronic toxicity including carcinogenesis, genotoxicity and epigenetic effects, reproductive and developmental toxicities, neurotoxicity, effects on the endocrine system, immunotoxicity and potential modes of action, combinational effects, and epidemiological studies on perfluorinated compounds). (orig.)

  7. Variability and exposure classification of urinary levels of non-essential metals aluminum, antimony, barium, thallium, tungsten and uranium in healthy adult men.

    Science.gov (United States)

    Wang, Yi-Xin; Pan, An; Feng, Wei; Liu, Chong; Huang, Li-Li; Ai, Song-Hua; Zeng, Qiang; Lu, Wen-Qing

    2017-12-21

    Arsenic, cadmium and lead are well-known toxic metals, and there are substantial studies on variability of these metals in urine to optimize design of exposure assessment. For urinary levels of other nonessential metals such as aluminum (Al), antimony (Sb), barium (Ba), thallium (Tl), tungsten (W) and uranium (U), however, their within-individual and between-individual variability are unclear. Therefore, we collected 529 samples from 11 healthy adult men on 8 days during a 3-month period. We measured urinary metals and creatinine (Cr) levels, assessed the reproducibility using intraclass correlation coefficients (ICCs), and performed sensitivity and specificity analyses to assess how well 1, 2 or 3 specimens could classify exposure. Al, Sb, Ba, W and U levels measured from spot samples varied greatly over days and months (Cr-adjusted ICCs = 0.01-0.14). Serial measures of Tl levels measured from spot samples had fair-to-good reproducibility over 5 consecutive days (Cr-adjusted ICC = 0.40), but worsened when the specimens were collected months apart (Cr-adjusted ICC = 0.16). To identify men who were highly exposed (top 33%) based on their 3-month averages, tests of single spot samples and tests of first-morning voids had high specificities (0.73-0.85) but relatively low sensitivities (0.27-0.60). Collection of repeated urine specimens from each individual improved the classification.

  8. (Vapor + Liquid) Equilibrium (VLE) for Binary Lead-Antimony System in Vacuum Distillation: New Data and Modeling Using Nonrandom Two-Liquid (NRTL) Model

    Science.gov (United States)

    Xu, Junjie; Kong, Lingxin; Xu, Baoqiang; Yang, Bin; You, Yanjun; Xu, Shuai; Zhou, Yuezhen; Li, Yifu; Liu, Dachun

    2016-09-01

    In this work, new experimental vapor-liquid equilibrium (VLE) data of lead-antimony alloy (Pb-Sb alloy) in vacuum distillation are reported. The activity coefficients of components of Pb-Sb alloy were calculated by using the NRTL model. The calculated average relative deviations were ±0.1425 and ±0.2433 pct, and the average standard deviations were ±0.0009 and ±0.0007, respectively, for Pb and Sb. The VLE phase diagrams, such as the temperature composition ( T- x) and pressure composition ( P-x) diagrams of Pb-Sb alloy in vacuum distillation were predicted based on the NRTL model and VLE theory. The predicted results are consistent with the new experimental data indicating that VLE phase diagrams obtained by this method are reliable. The VLE phase diagrams of alloys will provide an effective and intuitive way for the technical design and realization of recycling and separation processes. The VLE data may be used in separation processes design, and the thermodynamic properties as the key parameters in specific applications.

  9. Prediction of the percolation threshold and electrical conductivity of self-assembled antimony-doped tin oxide nanoparticles into ordered structures in PMMA/ATO nanocomposites.

    Science.gov (United States)

    Jin, Youngho; Gerhardt, Rosario A

    2014-12-24

    Electrical percolation in nanocomposites consisting of poly(methyl methacrylate) (PMMA) and antimony tin oxide (ATO) nanoparticles was investigated experimentally using monosize and polydisperse polymer particles. The nanocomposites were fabricated by compression molding at 170 °C. The matrix PMMA was transformed into space filling polyhedra while the ATO nanoparticles distributed along the sharp edges of the matrix, forming a 3D interconnected network. The measured electrical resistivity showed that percolation was achieved in these materials at a very low ATO content of 0.99 wt % ATO when monosize PMMA was used, whereas 1.48 wt % ATO was needed to achieve percolation when the PMMA was polydispersed. A parametric finite element approach was chosen to model this unique microstructure-driven self-assembling percolation behavior. COMSOL Multiphysics was used to solve the effects of phase segregation between the matrix and the filler using a 2D simplified model in the frequency domain of the AC/DC module. It was found that the percolation threshold (pc) is affected by the size ratio between the matrix and the filler in a systematic way. Furthermore, simulations indicate that small deviations from perfect interconnection result mostly in changes in the electrical resistivity while the minimum DC resistivity achievable in any given composite is governed by the electrical conductivity of the filler, which must be accurately known in order to obtain an accurate prediction. The model is quite general and is able to predict percolation behavior in a number of other similarly processed segregated network nanocomposites.

  10. Simplified sample preparation in the simultaneous measurement of whole blood antimony, bismuth, manganese, and zinc by inductively coupled plasma mass spectrometry.

    Science.gov (United States)

    Haglock-Adler, Carrie J; Strathmann, Frederick G

    2015-02-01

    We developed and validated a simplified sample preparation for the analysis of antimony (Sb), bismuth (Bi), manganese (Mn), and zinc (Zn) in whole blood. This simplification included a reduction in sample volume, removal of a lengthy acidic digestion, and optimization of the internal standard. Measurement of Sb, Bi, Mn and Zn in whole blood was conducted using inductively coupled-plasma mass spectrometry. Method performance characteristics, including intra- and inter-assay imprecision, accuracy, linearity, AMR, sensitivity, carryover, sample stability and assay stability were determined in accordance with clinical laboratory standards. In addition, analytical and clinical recoveries were assessed to investigate comparability between goat blood matrix and pooled patient blood. Established assay performance characteristics included inter- and intra-assay imprecision samples, proficiency testing samples, and comparison to an outside reference laboratory. This method overcomes the laborious acidic heat digestion previously used and replaces it with a simplified sample preparation involving an alkaline dilution. The method requires minimal sample preparation with the dilution of alkaline diluent and is validated to quantify Sb and Bi from 1 to 25 μg/L, Mn from 1 to 80 μg/L, and Zn from 50 to 1500 μg/dL in whole blood. Copyright © 2014 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  11. Migration of antimony from PET trays into food simulant and food: determination of Arrhenius parameters and comparison of predicted and measured migration data.

    Science.gov (United States)

    Haldimann, M; Alt, A; Blanc, A; Brunner, K; Sager, F; Dudler, V

    2013-01-01

    Migration experiments with small sheets cut out from ovenable PET trays were performed in two-sided contact with 3% acetic acid as food simulant at various temperatures. The fraction of diffusible antimony (Sb) was estimated to be 62% in the PET sample under study. Apparent diffusion coefficients of Sb in PET trays were determined experimentally. Measurement of migration between 20 and 150°C yielded a linear Arrhenius plot over a wide temperature range from which the activation energy (E(a)) of 188 ± 36 kJ mol(-1) and the pre-exponential factor (D(0)) of 3.6 × 10(14) cm(2) s(-1) were determined for diffusing Sb species. E (a) was similar to previously reported values for PET bottles obtained with a different experimental approach. E (a) and D (0) were applied as model parameters in migration modelling software for predicting the Sb transfer in real food. Ready meals intended for preparation in a baking oven were heated in the PET trays under study and the actual Sb migration into the food phase was measured by isotope dilution ICP-MS. It was shown that the predictive modelling reproduces correctly experimental data.

  12. Effects of storage temperature and duration on release of antimony and bisphenol A from polyethylene terephthalate drinking water bottles of China.

    Science.gov (United States)

    Fan, Ying-Ying; Zheng, Jian-Lun; Ren, Jing-Hua; Luo, Jun; Cui, Xin-Yi; Ma, Lena Q

    2014-09-01

    We investigated effects of storage temperature and duration on release of antimony (Sb) and bisphenol A (BPA) from 16 brands of polyethylene terephthalate (PET) drinking water bottles in China. After 1-week storage, Sb release increased from 1.88-8.32 ng/L at 4 °C, to 2.10-18.4 ng/L at 25 °C and to 20.3-2604 ng/L at 70 °C. The corresponding releases for BPA were less at 0.26-18.7, 0.62-22.6, and 2.89-38.9 ng/L. Both Sb and BPA release increased with storage duration up to 4-week, but their releasing rates decreased with storage time, indicating that Sb and BPA release from PET bottles may become stable under long term storage. Human health risk was evaluated based on the worst case, i.e., storage at 70 °C for 4-week. Chronic daily intake (CDI) caused by BPA release was below USEPA regulation, Sb release in one brand exceeded USEPA regulated CDI (400 ng/kg bw/d) with values of 409 and 1430 ng/kg bw/d for adult and children. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Microstructure and Electrical Properties of Antimony Telluride Thin Films Deposited by RF Magnetron Sputtering on Flexible Substrate Using Different Sputtering Pressures

    Science.gov (United States)

    Khumtong, T.; Sukwisute, P.; Sakulkalavek, A.; Sakdanuphab, R.

    2017-05-01

    The microstructural, electrical, and thermoelectric properties of antimony telluride (Sb2Te3) thin films have been investigated for thermoelectric applications. Sb2Te3 thin films were deposited on flexible substrate (polyimide) by radiofrequency (RF) magnetron sputtering from a Sb2Te3 target using different sputtering pressures in the range from 4 × 10-3 mbar to 1.2 × 10-2 mbar. The crystal structure, [Sb]:[Te] ratio, and electrical and thermoelectric properties of the films were analyzed by grazing-incidence x-ray diffraction (XRD) analysis, energy-dispersive x-ray spectroscopy (EDS), and Hall effect and Seebeck measurements, respectively. The XRD spectra of the films demonstrated polycrystalline structure with preferred orientation of (015), (110), and (1010). A high-intensity spectrum was found for the film deposited at lower sputtering pressure. EDS analysis of the films revealed the effects of the sputtering pressure on the [Sb]:[Te] atomic ratio, with nearly stoichiometric films being obtained at higher sputtering pressure. The stoichiometric Sb2Te3 films showed p-type characteristics with electrical conductivity, carrier concentration, and mobility of 35.7 S cm-1, 6.38 × 1019 cm-3, and 3.67 cm2 V-1 s-1, respectively. The maximum power factor of 1.07 × 10-4 W m-1 K-2 was achieved for the film deposited at sputtering pressure of 1.0 × 10-2 mbar.

  14. Mechanisms underlying the toxic effects of antimony species in human embryonic kidney cells (HEK-293) and their comparison with arsenic species.

    Science.gov (United States)

    Verdugo, Marcelo; Ogra, Yasumitsu; Quiroz, Waldo

    2016-01-01

    Antimony cytotoxicity was assessed in human embryonic kidney cells (HEK-293). Uptake, mitochondrial respiratory activity, ROS generation and diffusional kinetics were measured using fluorescence recovery after photobleaching (FRAP). Furthermore, the toxic effect induced by Sb was compared with As toxicity in regard to ROS generation and diffusional kinetics, which provides information on the protein aggregation process. Our results show a favored uptake of Sb(III) and a more severe effect, decreasing the mitochondrial activity more than in the presence of Sb(V). In comparison with As, the Sb species did not generate a significant increase in ROS generation, which was observed with As(III) and As(V). FRAP analysis yielded important information on the diffusion and binding dynamics of live cells in presence of these metalloids. The mobile fraction showed a strong decrease with the As species and Sb(III). The diffusion rate and the k off-rate were significantly decreased for the As and Sb species but were more strong in the presence of As(III).

  15. Antimony speciation in soils: improving the detection limits using post-column pre-reduction hydride generation atomic fluorescence spectroscopy (HPLC/pre-reduction/HG-AFS).

    Science.gov (United States)

    Quiroz, Waldo; Olivares, David; Bravo, Manuel; Feldmann, Jorg; Raab, Andrea

    2011-04-15

    HG-AFS is highly sensitive and low cost detection system and its use for antimony chemical speciation coupled to HPLC is gaining popularity. However speciation analysis in soils is strongly hampered because the most efficient extractant reported in the literature (oxalic acid) strongly inhibits the generation of SbH(3) by Sb(V), the major species in this kind of matrix, severely affecting its detection limits. The purpose of this research is to reduce the detection limit of Sb(V), by using a post column on-line reduction system with l-cysteine reagent (HPLC/pre-reduction/HG-AFS). The system was optimized by experimental design, optimum conditions found were 2% (w/v) and 10°C temperature coil. Detection limits of Sb(V) and Sb(III) in oxalic acid (0.25 mol L(-1)) were improved from 0.3 and 0.1 μg L(-1) to 0.07 and 0.07 μg L(-1), respectively. The methodology developed was applied to Chilean soils, where Sb(V) was the predominant species. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. The influence of expanded graphite on thermal properties for paraffin/high density polyethylene/chlorinated paraffin/antimony trioxide as a flame retardant phase change material

    International Nuclear Information System (INIS)

    Zhang Ping; Song Lei; Lu Hongdian; Wang Jian; Hu Yuan

    2010-01-01

    The influences of expanded graphite (EG) on the thermal properties of chlorinated paraffin (CP) and antimony trioxide (AT) on phase change material which bases on paraffin/high density polyethylene (HDPE) are studied. Differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), thermogravimetric analysis-Fourier transform infrared spectrometry (TGA-FTIR), microscale combustion calorimeter (MCC) and cone calorimeter (CONE) were used to evaluate the influence of EG on paraffin/HDPE/CP/AT system. The DSC results indicated that the latent heat value of PCM could be increased when the mass fraction of HDPE was decreased in the PCM, and EG could confine the molecular heat movement of paraffin. EG could improve the thermal stability and increase the char residue at high temperature for paraffin/HDPE/CP/AT hybrid. The volatilized products formed on thermal degradation of paraffin/HDPE/CP/AT with EG showed the release of CO 2 gas was hastened and increased, and the amount of combustible gases were decreased by TGA-FTIR analysis. The MCC and CONE results presented that the flame retardant efficiency of CP/AT could be improved by adding EG in paraffin/HDPE/CP/AT system.

  17. Effectiveness of chemical amendments for stabilisation of lead and antimony in risk-based land management of soils of shooting ranges.

    Science.gov (United States)

    Sanderson, Peter; Naidu, Ravi; Bolan, Nanthi

    2015-06-01

    This study aims to examine the effectiveness of amendments for risk-based land management of shooting range soils and to explore the effectiveness of amendments applied to sites with differing soil physiochemical parameters. A series of amendments with differing mechanisms for stabilisation were applied to four shooting range soils and aged for 1 year. Chemical stabilisation was monitored by pore water extraction, toxicity characteristic leaching procedure (TCLP) and the physiologically based extraction test (PBET) over 1 year. The performance of amendments when applied in conditions reflecting field application did not match the performance in the batch studies. Pore water-extractable metals were not greatly affected by amendment addition. TCLP-extractable Pb was reduced significantly by amendments, particularly lime and magnesium oxide. Antimony leaching was reduced by red mud but mobilised by some of the other amendments. Bioaccessible Pb measured by PBET shows that bioaccessible Pb increased with time after an initial decrease due to the presence of metallic fragments in the soil. Amendments were able to reduce bioaccessible Pb by up to 50 %. Bioaccessible Sb was not readily reduced by soil amendments. Soil amendments were not equally effective across the four soils.

  18. Determination of antimony and tin in beverages using inductively coupled plasma-optical emission spectrometry after ultrasound-assisted ionic liquid dispersive liquid-liquid phase microextraction.

    Science.gov (United States)

    Biata, N Raphael; Nyaba, Luthando; Ramontja, James; Mketo, Nomvano; Nomngongo, Philiswa N

    2017-12-15

    The aim of this study was to develop a simple and fast ultrasound-assisted ionic liquid dispersive liquid-liquid phase microextraction (UA-IL-DLLME) method for preconcetration of trace antimony and tin in beverage samples. The novelty of this study was based on the application of ligandless UA-IL-DLLME using low-density ionic liquid and organic solvents for preconcentration of Sb and Sn. The concentration of Sb and Sn were quantified using ICP-OES. Under the optimum conditions, the calibration graph was found to be LOQ-250µgL -1 (r 2 =0.9987) for Sb and LOQ-350µgL -1 for Sn. The LOD and LOQ of Sb and Sn ranged from 1.2to 2.5ngL -1 and 4.0 to 8.3ngL -1 , respectively, with high preconcentration factors. The precisions (%RSD) of the proposed method ranged from 2.1% to 2.5% and 3.9% to 4.7% for Sb and Sn, respectively. The proposed method was successfully applied for determination of Sb and Sn in beverages. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Study of the influence of storage conditions on the quality and migration levels of antimony in polyethylene terephthalate-bottled water.

    Science.gov (United States)

    Payán, Luis; Poyatos, M Teresa; Muñoz, Lucía; La Rubia, M Dolores; Pacheco, Rafael; Ramos, Natividad

    2017-06-01

    The main objectives of this study are to determine the presence of antimony in water stored in polyethylene terephthalate bottles and the influence of temperature and time over the migration levels. For this purpose, Sb determination was carried out in water at different experimental conditions: storage for one to three weeks at 25 to 80 ℃; long-term (six months) storage at room temperature between 16 and 24 ℃ and storage in car during summer which is a common consumer's habit. In addition, water quality analysis was developed after different time-temperature storage conditions. All the samples at the end of their storage conditions were analyzed by inductively coupled plasma mass spectrometry. The limit of detection and quantification were 0.50 and 0.80 µg/L, respectively. The results for the bottled water stored during six months indicated that the average Sb concentration was 0.332 ± 0.015 µg/L. This value is below the European maximum permissible migration level of 5 µg/L. With regard to the newly bottled water, no Sb was detected at the initial time for all temperatures studied. However, the Sb concentration in water increased with both time and temperature. The levels of Sb started exceeding the European limits when the samples were stored at 60 ℃ for two weeks.

  20. Q-switched erbium doped fiber laser using antimony telluride-polyvinyl alcohol (Sb2Te3-PVA) as saturable absorber

    Science.gov (United States)

    Quisar Lokman, Muhammad; Ahmad, Fauzan; Wadi Harun, Sulaiman

    2017-11-01

    Q-switched erbium doped fiber laser was demonstrated using antimony telluride (Sb2Te3) as saturable absorber (SA). The SA was fabricated by adding Sb3Te2 powder into PVA suspension and left dry in room temperature for two days. Then, the SA was sandwiched in between two FC/PC fiber ferrules, which can provide easy integration and flexibility into the laser cavity. Stable and self-started Q-switched laser operates at 1531 nm center wavelength. The laser repetition rate increased from 54.5 kHz to 88.4 kHz and pulse duration decreased from 6.84 μs to 4.58 μs as the pump power increased. A signal to noise ratio value of 55 dB was achieved at pump power 130 mW. At the maximum pump power, the average output power and pulse energy are 0.26 mW and 2.78 nJ.

  1. Trace determination of antimony by hydride generation atomic absorption spectrometry with analyte preconcentration/atomization in a dielectric barrier discharge atomizer.

    Science.gov (United States)

    Zurynková, Pavla; Dědina, Jiří; Kratzer, Jan

    2018-06-20

    Atomization conditions for antimony hydride in the plasma atomizer based on a dielectric barrier discharge (DBD) with atomic absorption spectrometric detection were optimized. Argon was found as the best discharge gas under a flow rate of 50 mL min - 1 while the DBD power was optimum at 30 W. Analytical figures of merit including interference study of As, Se and Bi have been subsequently investigated and the results compared to those found in an externally heated quartz tube atomizer (QTA). The limit of detection (LOD) reached in DBD (0.15 ng mL -1  Sb) is comparable to that observed in QTA (0.14 ng mL -1  Sb). Finally, possibility of Sb preconcentration by stibane in situ trapping in a DBD atomizer was studied. For trapping time of 300 s, the preconcentration efficiency and LOD, respectively, were 103 ± 2% and 0.02 ng mL -1 . Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Selenium-75-labelled foliate compounds

    International Nuclear Information System (INIS)

    1974-01-01

    A saturation method to analyze a foliate is presented; it uses competitive reaction of the compound to be measured and of a radioactive-labelled version of this compound with a reagent specific to this compound present in insufficient quantity to combine with the whole of the compound and its labelled version, separation of the bound compound from its non-bound homologue and measurement of the radioactivity concentration in the bound compound, the non-bound compound or both. The radioactive isotope used in the labelled foliate is selenium 75 [fr

  3. Synthetic Aperture Compound Imaging

    DEFF Research Database (Denmark)

    Hansen, Jens Munk

    Medical ultrasound imaging is used for many purposes, e.g. for localizing and classifying cysts, lesions, and other processes. Almost any mass is first observed using B-mode imaging and later classified using e.g. color flow, strain, or attenuation imaging. It is therefore important that the B......, it is demonstrated through theoretical considerations that the compound effect achieved is close to a theoretical maximum for the amount of compounding attainable and using a -pitch convex array transducer, the first in-vivo images are created. The computational demands for an implementation are massive...... and the limiting factor is the amount of memory IO resources available. An equally high demand for memory throughput is found in the computer gaming industry, where a large part of the processing takes place on the graphics processing unit (GPU). Using the GPU, a framework for synthetic aperture imaging...

  4. Compound semiconductor device modelling

    CERN Document Server

    Miles, Robert

    1993-01-01

    Compound semiconductor devices form the foundation of solid-state microwave and optoelectronic technologies used in many modern communication systems. In common with their low frequency counterparts, these devices are often represented using equivalent circuit models, but it is often necessary to resort to physical models in order to gain insight into the detailed operation of compound semiconductor devices. Many of the earliest physical models were indeed developed to understand the 'unusual' phenomena which occur at high frequencies. Such was the case with the Gunn and IMPATI diodes, which led to an increased interest in using numerical simulation methods. Contemporary devices often have feature sizes so small that they no longer operate within the familiar traditional framework, and hot electron or even quantum­ mechanical models are required. The need for accurate and efficient models suitable for computer aided design has increased with the demand for a wider range of integrated devices for operation at...

  5. Hydrogen in compound semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Haller, E.E.

    1993-05-01

    Progress in the understanding of hydrogen and its interactions in III/V and II/VI compound semiconductors is reviewed. Donor, acceptor and deep level passivation is well established in III/V compounds based on electrical measurements and on spectroscopic studies. The hydrogen donor levels in GaAs and GaP are estimated to lie near E{sub v}+0.5 eV and E{sub v}+0.3 eV, respectively. Arsenic acceptors have been passivated by hydrogen in CdTe and the very first nitrogen-hydrogen local vibrational model spectra in ZnSe have been reported. This long awaited result may lead to an explanation for the poor activation of nitrogen acceptors in ZnSe grown by techniques which involve high concentrations of hydrogen.

  6. Process for compound transformation

    KAUST Repository

    Basset, Jean-Marie

    2016-12-29

    Embodiments of the present disclosure provide for methods of using a catalytic system to chemically transform a compound (e.g., a hydrocarbon). In an embodiment, the method does not employ grafting the catalyst prior to catalysis. In particular, embodiments of the present disclosure provide for a process of hydrocarbon (e.g., C1 to C20 hydrocarbon) metathesis (e.g., alkane, olefin, or alkyne metathesis) transformation, where the process can be conducted without employing grafting prior to catalysis.

  7. Polymeric coordination compounds

    Indian Academy of Sciences (India)

    Administrator

    Ce(dipic)3Sr(dipicH2)(OH2)3·5H2O (4) (dipicH2 – dipicolinic acid) exhibits 1-D polymeric chain structure, built up of alternating nine coordinate Ce and eight coordinate. Sr polyhedra. The analogous Ce–Ba compound (5) exhibits a polymeric chain built up of nine coordinate Ba units only, arranged in a hexagonal lattice.

  8. Bronzes and relative compounds

    International Nuclear Information System (INIS)

    Uehlls, A.

    1987-01-01

    Preparation and the crystal structure of bronzes based on complex oxides of transition (Ti, V, Nb, Ta, Mo, W, Re, Ru and etc.) and alkali metals, as well as oxides of some other elements (Sr, In, La and etc.) are described. Peculiarities of formation of the structure of tetragonal, tungsten, molybdenum, vanadium bronzes and their analogs depending on the chemical composition of these compounds are considered

  9. Antifungal compounds from cyanobacteria.

    Science.gov (United States)

    Shishido, Tânia K; Humisto, Anu; Jokela, Jouni; Liu, Liwei; Wahlsten, Matti; Tamrakar, Anisha; Fewer, David P; Permi, Perttu; Andreote, Ana P D; Fiore, Marli F; Sivonen, Kaarina

    2015-04-13

    Cyanobacteria are photosynthetic prokaryotes found in a range of environments. They are infamous for the production of toxins, as well as bioactive compounds, which exhibit anticancer, antimicrobial and protease inhibition activities. Cyanobacteria produce a broad range of antifungals belonging to structural classes, such as peptides, polyketides and alkaloids. Here, we tested cyanobacteria from a wide variety of environments for antifungal activity. The potent antifungal macrolide scytophycin was detected in Anabaena sp. HAN21/1, Anabaena cf. cylindrica PH133, Nostoc sp. HAN11/1 and Scytonema sp. HAN3/2. To our knowledge, this is the first description of Anabaena strains that produce scytophycins. We detected antifungal glycolipopeptide hassallidin production in Anabaena spp. BIR JV1 and HAN7/1 and in Nostoc spp. 6sf Calc and CENA 219. These strains were isolated from brackish and freshwater samples collected in Brazil, the Czech Republic and Finland. In addition, three cyanobacterial strains, Fischerella sp. CENA 298, Scytonema hofmanni PCC 7110 and Nostoc sp. N107.3, produced unidentified antifungal compounds that warrant further characterization. Interestingly, all of the strains shown to produce antifungal compounds in this study belong to Nostocales or Stigonematales cyanobacterial orders.

  10. Changes induced by gamma radiation in nanocomposites based on copper II and antimony sulfides in commercial poly(methyl methacrylate) matrix; Alteracoes induzidas pela radiacao gama em nanocompositos a base dos sulfetos de cobre II e de antimonio na matriz de poli(metacrilato de metila) comercial

    Energy Technology Data Exchange (ETDEWEB)

    Albuquerque, M.C.C. de; Garcia, O.P.; Aquino, K.A.S.; Araujo, E.S., E-mail: esa@ufpe.b [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear

    2010-07-01

    Poly (methyl methacrylate) (PMMA) is a polymer with wide application in the manufacture of medical devices that is exposed to gamma irradiation. Currently the use of composite materials has been disseminated and PMMA is an excellent polymer matrix to package various materials. This study aimed to analyze the changes induced by gamma irradiation (25 kGy) on the properties of PMMA nanocomposites with nanoparticles of copper II sulfide (250nm-900nm) and antimony sulfite (300-500 nm). The nanoparticles were added to the polymer in different concentrations and synthesized by ultrasonic irradiation from the corresponding chlorides with thioacetamide. Viscometric results showed a good radioprotective effect of nanoparticles of copper and antimony. It was found a good protection of nanoparticles on PMMA matrix in the concentration of 0.3% wt. The protections of 75% and 50% were calculated for nanoparticles of antimony and copper II, respectively. (author)

  11. Fluorinated antimony(v) derivatives: strong Lewis acidic properties and application to the complexation of formaldehyde in aqueous solutions.

    Science.gov (United States)

    Tofan, Daniel; Gabbaï, François P

    2016-11-01

    As part of our ongoing studies of water tolerant Lewis acids, we have synthesized and investigated the properties of Sb(C 6 F 5 ) 3 (O 2 C 6 Cl 4 ), a fluorinated stiborane whose Lewis acidity approaches that of B(C 6 F 5 ) 3 . While chloroform solutions of this Lewis acid can be kept open to air or exposed to water for extended periods of time, this new Lewis acid reacts with P t Bu 3 and paraformaldehyde to form the corresponding formaldehyde adduct t Bu 3 P-CH 2 -O-Sb(C 6 F 5 ) 3 (O 2 C 6 Cl 4 ). To test if this reactivity can also be observed with systems that combine the phosphine and the stiborane within the same molecule, we have also prepared o -C 6 H 4 (PPh 2 )(SbAr 2 (O 2 C 6 Cl 4 )) (Ar = Ph, C 6 F 5 ). These yellow compounds, which possess an intramolecular P→Sb interaction, are remarkably inert to water but do, nonetheless, react with and accomodate formaldehyde into the P/Sb pocket. In the case of the fluorinated derivative o -C 6 H 4 (PPh 2 )(Sb(C 6 F 5 ) 2 (O 2 C 6 Cl 4 )), formaldehyde complexation, which occurs in water/dichloromethane biphasic mixtures, is accompanied by a colourimetric turn-off response thus highlighting the potential that this chemistry holds in the domain of molecular sensing.

  12. Offset Compound Gear Drive

    Science.gov (United States)

    Stevens, Mark A.; Handschuh, Robert F.; Lewicki, David G.

    2010-01-01

    The Offset Compound Gear Drive is an in-line, discrete, two-speed device utilizing a special offset compound gear that has both an internal tooth configuration on the input end and external tooth configuration on the output end, thus allowing it to mesh in series, simultaneously, with both a smaller external tooth input gear and a larger internal tooth output gear. This unique geometry and offset axis permits the compound gear to mesh with the smaller diameter input gear and the larger diameter output gear, both of which are on the same central, or primary, centerline. This configuration results in a compact in-line reduction gear set consisting of fewer gears and bearings than a conventional planetary gear train. Switching between the two output ratios is accomplished through a main control clutch and sprag. Power flow to the above is transmitted through concentric power paths. Low-speed operation is accomplished in two meshes. For the purpose of illustrating the low-speed output operation, the following example pitch diameters are given. A 5.0 pitch diameter (PD) input gear to 7.50 PD (internal tooth) intermediate gear (0.667 reduction mesh), and a 7.50 PD (external tooth) intermediate gear to a 10.00 PD output gear (0.750 reduction mesh). Note that it is not required that the intermediate gears on the offset axis be of the same diameter. For this example, the resultant low-speed ratio is 2:1 (output speed = 0.500; product of stage one 0.667 reduction and stage two 0.750 stage reduction). The design is not restricted to the example pitch diameters, or output ratio. From the output gear, power is transmitted through a hollow drive shaft, which, in turn, drives a sprag during which time the main clutch is disengaged.

  13. Toxicology of alkylmercury compounds.

    Science.gov (United States)

    Aschner, Michael; Onishchenko, Natalia; Ceccatelli, Sandra

    2010-01-01

    Methylmercury is a global pollutant and potent neurotoxin whose abundance in the food chain mandates additional studies on the consequences and mechanisms of its toxicity to the central nervous system. Formulation of our new hypotheses was predicated on our appreciation for (a) the remarkable affinity of mercurials for the anionic form of sulfhydryl (-SH) groups, and (b) the essential role of thiols in protein biochemistry. The present chapter addresses pathways to human exposure of various mercury compounds, highlighting their neurotoxicity and potential involvement in neurotoxic injury and neurodegenerative changes, both in the developing and senescent brain. Mechanisms that trigger these effects are discussed in detail.

  14. Flavour Compounds in Fungi

    DEFF Research Database (Denmark)

    Ravasio, Davide Antonio

    from the catabolism of amino acids. These compounds are produced by the Ehrlich pathway. The conversion of amino acids into aroma alcohols is accomplished by three enzymatic steps: i) a transamination, ii) a decarboxylation and iii) a dehydration reaction. The transaminase and decarboxylase enzymes...... and 2-phenylacetate. The last part of this thesis presents the initial characterization of twenty non-conventional yeasts (NCY) and their potential application in fermentative processes. These strains have been selected as they have been previously isolated from various fermented food sources...

  15. Mineralogical controls on antimony and arsenic mobility during tetrahedrite-tennantite weathering at historic mine sites Špania Dolina-Piesky and Lubietová-Svätodušná, Slovakia

    Energy Technology Data Exchange (ETDEWEB)

    Bor,; #269; inová rAdková, AnežkA; Jamieson, Heather; Lalinská-Voleková, Bronislava; Majzlan, Juraj; Števko, Martin; Chovan, Martin

    2018-01-01

    The legacy of copper (Cu) mining at Špania Dolina-Piesky and Lubietová-Svätodušná (central Slovakia) is waste rock and soil, surface waters, and groundwaters contaminated with antimony (Sb), arsenic (As), Cu, and other metals. Copper ore is hosted in chalcopyrite (CuFeS2) and sulfosalt solid-solution tetrahedrite-tennantite {Cu6[Cu4(Fe,Zn)2]Sb4S13–Cu6[Cu4(Fe,Zn)2]As4S13} that show wide-spread oxidation characteristic by olive-green color secondary minerals. Tetrahedrite-tennantite can be a significant source of As and Sb contamination. Synchrotron-based μ-XRD, μ-XRF, and μ-XANES combined with electron microprobe analyses have been used to determine the mineralogy, chemical composition, element distribution, and Sb speciation in tetrahedrite-tennantite oxidation products in waste rock. Our results show that the mobility of Sb is limited by the formation of oxidation products such as tripuhyite and roméite group mineral containing 36.54 wt% Sb for samples where the primary mineral chemical composition is close to tetrahedrite end-member. Antimony K-edge μ-XANES spectra of these oxidation products indicate that the predominant Sb oxidation state is 5+. Arsenic and Cu are also hosted by amorphous phases containing 6.23 wt% Sb on average and these are intergrown with tripuhyite and roméite. Antimony in this environment is not very mobile, meaning it is not easily released from solid phases to water, especially compared to As, Cu, and S. For samples where the primary sulfosalt is close to tennantite composition, the oxidation products associated with tennantite relicts contain 2.43 wt% Sb and are amorphous. The variable solubility of the secondary minerals that have been identified is expected to influence mobility of Sb and As in near-surface environment.

  16. Development and pharmacokinetic of antimony encapsulated in liposomes of phosphatidylserine using radioisotopes in experimental leishmaniasis; Desenvolvimento e farmacocinetica de antimonio encapsulado em lipossomas de fosfatidilserina utilizando radioisotopos em leishmaniose experimental

    Energy Technology Data Exchange (ETDEWEB)

    Borborema, Samanta Etel Treiger

    2010-07-01

    Leishmaniasis are a complex of parasitic diseases caused by intra macrophage protozoa of the genus Leishmania, and is fatal if left untreated. Pentavalent antimonials, though toxic and their mechanism of action being unclear, remain the first-line drugs for treatment. Effective therapy could be achieved by delivering antileishmanial drugs to these sites of infection. Liposomes are phospholipid vesicles that promote improvement in the efficacy and action of drugs in target cell. Liposomes are taken up by the cells of mononuclear phagocytic system (MPS). The purpose of this study was to develop a preparation of meglumine antimonate encapsulated in liposomes of phosphatidylserine and to study its pharmacokinetic in healthy mice to establish its metabolism and distribution. Quantitative analysis of antimony from liposomes demonstrated that Neutron Activation Analysis was the most sensitive technique with almost 100 % of accuracy. All liposome formulations presented a mean diameter size of 150 nm. The determination of IC{sub 50} in infected macrophage showed that liposome formulations were between 10 - 63 fold more effective than the free drug, indicating higher selectivity index. By fluorescence microscopy, an increased uptake of fluorescent-liposomes was seen in infected macrophages during short times of incubation compared with non-infected macrophages. Biodistribution studies showed that meglumine antimonate irradiated encapsulated in liposomes of phosphatidylserine promoted a targeting of antimony for MPS tissues and maintained high doses in organs for a prolonged period. In conclusion, these data suggest that meglumine antimonate encapsulated in liposomes showed higher effectiveness than the non-liposomal drug against Leishmania infection. The development of liposome formulations should be a new alternative for the chemotherapy of infection diseases, especially Leishmaniasis, as they are used to sustain and target pharmaceuticals to the local of infection. (author)

  17. Improved Antileishmanial Activity of Dppz through Complexation with Antimony(III and Bismuth(III: Investigation of the Role of the Metal

    Directory of Open Access Journals (Sweden)

    Cynthia Demicheli

    2012-10-01

    Full Text Available Two novel trivalent antimony(III and bismuth(III complexes with the nitrogen-donor heterocyclic ligand dipyrido[3,2-a:2',3'-c]phenazine (dppz were synthesized and characterized as [Sb(dppzCl3]∙H2O∙CH3OH and [Bi(dppzCl3]. The crystal structure of Sb(III complex was determined by X-ray crystallography. These complexes were evaluated for their activity against the promastigote form of Sb(III-sensitive and –resistant Leishmania infantum chagasi and Leishmania amazonensis strains. Both complexes were more effective than dppz alone in inhibiting the growth of Leishmania promastigotes and were at least 77 and 2,400 times more active than potassium antimonyl tartrate in Sb(III-sensitive and -resistant Leishmania, respectively. The cytotoxicity of dppz and its complexes against mouse peritoneal macrophages occurred at dppz concentrations at least 6-fold greater than those found to be active against Leishmania promastigotes.To investigate the role of the metal in the improved antileishmanial activity of dppz, the activity of the Sb(III complex was compared between the Sb-resistant mutants and their respective parental sensitive strains. The lack of cross-resistance to the Sb(III-dppz complex together with the much lower activity of antimonyl tartrate, SbCl3 and BiCl3 strongly support the model that the metal is not active by itself but improves the activity of dppz through complexation.

  18. The antimony-group 11 chemical bond: dissociation energies of the diatomic molecules CuSb, AgSb, and AuSb.

    Science.gov (United States)

    Carta, V; Ciccioli, A; Gigli, G

    2014-02-14

    The intermetallic molecules CuSb, AgSb, and AuSb were identified in the effusive molecular beam produced at high temperature under equilibrium conditions in a double-cell-like Knudsen source. Several gaseous equilibria involving these species were studied by mass spectrometry as a function of temperature in the overall range 1349-1822 K, and the strength of the chemical bond formed between antimony and the group 11 metals was for the first time measured deriving the following thermochemical dissociation energies (D°(0), kJ/mol): 186.7 ± 5.1 (CuSb), 156.3 ± 4.9 (AgSb), 241.3 ± 5.8 (AuSb). The three species were also investigated computationally at the coupled cluster level with single, double, and noniterative quasiperturbative triple excitations (CCSD(T)). The spectroscopic parameters were calculated from the potential energy curves and the dissociation energies were evaluated at the Complete Basis Set limit, resulting in an overall good agreement with experimental values. An approximate evaluation of the spin-orbit effect was also performed. CCSD(T) calculations were further extended to the corresponding group 11 arsenide species which are here studied for the first time and the following dissociation energies (D°(0), kJ/mol): 190 ± 10 (CuAs), 151 ± 10 (AgAs), 240 ± 15 (AuAs) are proposed. Taking advantage of the new experimental and computational information here presented, the bond energy trends along group 11 and 4th and 5th periods of the periodic table were analyzed and the bond energies of the diatomic species CuBi and AuBi, yet experimentally unobserved, were predicted on an empirical basis.

  19. People with diabetes, respiratory, liver or mental disorders, higher urinary antimony, bisphenol A, or pesticides had higher food insecurity: USA NHANES, 2005-2006.

    Science.gov (United States)

    Shiue, Ivy

    2016-01-01

    This study was aimed to examine the prevalence of food insecurity and what social, health, and environmental characteristics could constitute such situation in a national and population-based setting. Data was retrieved from the National Health and Nutrition Examination Survey, 2005-2006. Information on demographics, lifestyle factors, self-reported ever medical conditions in the past and self-reported food security conditions in the last 12 months calculated on the household level was obtained by household interview. Bloods and urines (subsample) were collected at the interview as well. Only adults aged 20 years and above (n = 4979) were included for statistical analysis in the present study. Chi-square test, t test, and survey-weighted logistic regression modeling were performed. Three thousand eight hundred thirty-four (77.9%) people were with full food security, 466 (9.5%) people were with marginal food security and 624 (12.7%) people were with low or very low food security. Being younger, having higher ratios of family income to poverty thresholds (due to low level of education or lack of financial support), having prior asthma, arthritis, chronic bronchitis, depression, diabetes, eczema, emphysema or liver problems, having higher levels of serum cotinine, urinary antimony, bisphenol A, pesticides, or having lower levels of urinary Benzophenone-3 were associated with food insecurity. In addition to socioeconomic and smoking conditions, evidence on people with several prior health conditions and being exposed to environmental chemicals and food insecurity is further provided. Future social, health and environmental policy, and programs protecting people from food insecurity by considering both health and environmental factors mentioned above would be suggested.

  20. Efficiency of Iron-Based Oxy-Hydroxides in Removing Antimony from Groundwater to Levels below the Drinking Water Regulation Limits

    Directory of Open Access Journals (Sweden)

    Konstantinos Simeonidis

    2017-02-01

    Full Text Available This study evaluates the efficiency of iron-based oxy-hydroxides to remove antimony from groundwater to meet the requirements of drinking water regulations. Results obtained by batch adsorption experiments indicated that the qualified iron oxy-hydroxide (FeOOH, synthesized at pH 4 for maintaining a high positive charge density (2.5 mmol OH−/g achieved a residual concentration of Sb(III below the EU drinking water regulation limit of 5 μg/L by providing an adsorption capacity of 3.1 mg/g. This is more than twice greater compared either to similar commercial FeOOHs (GFH, Bayoxide or to tetravalent manganese feroxyhyte (Fe-MnOOH adsorbents. In contrast, all tested adsorbents failed to achieve a residual concentration below 5 μg/L for Sb(V. The higher efficiency of the qualified FeOOH was confirmed by rapid small-scale column tests, since an adsorption capacity of 3 mg Sb(III/g was determined at a breakthrough concentration of 5 μg/L. However, it completely failed to achieve Sb(V concentrations below 5 μg/L even at the beginning of the column experiments. The results of leaching tests classified the spent qualified FeOOH to inert wastes. Considering the rapid kinetics of this process (i.e., 85% of total removal was performed within 10 min, the developed qualified adsorbent may be promoted as a prospective material for point-of-use Sb(III removal from water in vulnerable communities, since the adsorbent’s cost was estimated to be close to 30 ± 3.4 €/103 m3 for every 10 μg Sb(III/L removed.

  1. Dispersive micro-solid phase extraction combined with dispersive liquid-liquid microextraction for speciation analysis of antimony by electrothermal vaporization inductively coupled plasma mass spectrometry

    Science.gov (United States)

    Chen, Shizhong; Zhu, Shengping; Lu, Dengbo

    2018-01-01

    A method was developed for speciation analysis of antimony by electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICP-MS) after preconcentration/separation using dispersive micro-solid phase extraction (DMSPE) and dispersive liquid-liquid micro-extraction (DLLME). In DMSPE, titanium dioxide nanofibers were used for preconcentration and separation of analytes. The upper aqueous phase and elution solution from DMSPE were used for further preconcentration and separation of Sb(III) and Sb(V) by DLLME without any pre-oxidation or pre-reduction operation, respectively. The extracts from DLLME were used for ETV-ICP-MS determination with APDC as a chemical modifier. Under optimal conditions, the detection limits of this method were 0.019 and 0.025 pg mL- 1 with relative standard deviations of 5.7% and 6.9% for Sb(III) and Sb(V) (c = 1.0 ng mL- 1, n = 9), respectively. This method was applied for speciation analysis of Sb and its distribution in the tea leaves and the tea infusion, including total, suspended, soluble, organic and inorganic Sb as well as Sb(III) and Sb(V). The results showed that the contents of Sb are 62.7, 12.9 and 47.3 ng g- 1 in the tea leaves, tea residue and tea soup, respectively; those of soluble, organic, inorganic, Sb(III) and Sb(V) are 0.41, 0.11, 0.29, 0.21 and 0.07 ng mL- 1 in the tea soup, respectively. A certified reference material of tea leaves (GBW 07605) was analyzed by this method with satisfactory results.

  2. Palaeozoic Magmatism Associated with Gold-Antimony-Tin-Tungsten-Lead-Zinc and Silver Mineralization in the Neighbouring of Porto, Northern Portugal

    Science.gov (United States)

    Couto, Helena; Roger, Guy

    2017-12-01

    In the studied area there are evidences of Palaeozoic magmatism along the stratigraphic succession from Cambrian to Carboniferous. Igneous, volcanic and sub-volcanic rocks occur along and around a significant Variscan structure, the Valongo Anticline, an asymmetrical antiform anticline, trending NW-SE, located in Central Iberian Zone in the neighbourhood of Porto (Northern Portugal). Mineralizations of gold-antimony-tin-tungsten-lead-zinc and silver occur in the area. Magmatism related to acid and basic subvolcanic and volcanic rocks occurs interbedded in Montalto Formation metasediments (conglomerates, quartzite, wakes and slates) of Cambrian age. In the transition Cambrian-Ordovician (Tremadocian?) underlying the Lower Ordovician massive quartzite of Santa Justa Formation (Floian age), volcanic rocks show bimodal composition and occur interbedded in a lithologic association mainly composed of conglomerate and quartzite with minor slate and wake intercalations. The acid volcanism consists of interbedded volcanoclastic rocks of rhyolitic affinities and black and green cherts in thick layers represent the basic volcanism. To the top of this basal Early Ordovician volcano-sedimentary succession, overlaying Floian massive quartzites, a succession of interbedded quartzite’s, wackes and slates, enriched in ironstones in the normal limb, and bearing prints of volcanic origin occur. Sub-concordant quartz veins (exhalative-origin) interbedded in the ironstones were interpreted as volcanic layers recrystallized during the circulation of hydrothermal mineralizing fluids. The presence of igneous rocks in Palaeozoic Carboniferous metasediments around Porto is known since middle of nineteen century. Granodioritic porphyry intrusion occurs interbedded in carboniferous metasediments. Metasedimentary country rocks are surrounded by pre- to post-orogenic Variscan granites with no direct spatial relationship with mineralization but hidden granitic apexes suggest an indirect

  3. Chemistry of nitrogen oxide compounds

    International Nuclear Information System (INIS)

    Wells, A.

    1987-01-01

    The structure of nitrogen oxide compounds including: nitrates and nitrites, nitrosyl compounds of transition metals, rare earth, transition metal and actinide complexes, where nitrite- and nitrate ions are presented as ligands, is considered. Oxonitrate compounds, e.g. RbUO 2 (NO 3 ) 3 are also considered. The values of lengths and angles of bonds for some of these compounds are presented, volatility of Cd, Be and other metal nitrates are also discussed

  4. Frequency effects in compound production

    NARCIS (Netherlands)

    Bien, H.; Levelt, W.J.M.; Baayen, R.H.

    2005-01-01

    Four experiments investigated the role of frequency information in compound production by independently varying the frequencies of the first and second constituent as well as the frequency of the compound itself. Pairs of Dutch noun-noun compounds were selected such that there was a maximal contrast

  5. 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...

  6. Catalytic properties of niobium compounds

    International Nuclear Information System (INIS)

    Tanabe, K.; Iizuka, T.

    1983-04-01

    The catalytic activity and selectivity of niobium compounds including oxides, salts, organometallic compounds and others are outlined. The application of these compounds as catalysts to diversified reactions is reported. The nature and action of niobium catalysts are characteristic and sometimes anomalous, suggesting the necessity of basic research and the potential use as catalysts for important processes in the chemical industry. (Author) [pt

  7. Organometallic compounds in the environment

    National Research Council Canada - National Science Library

    Craig, P. J

    2003-01-01

    ... of Organometallic Species in the Environment 20 1.10 Stability of Organometallic Compounds in Biological Systems 1.11 G eneral Comments on the Toxicities of Organometallic Compounds 22 1.12 General Considerations on Environmental R eactivity of Organometallic Compounds 24 1.13 Microbial Biotransformation of Metals and M etalloids 25 1.13.1 Introduction 25 1...

  8. Microbiological oxidation of antimony(III) with oxygen or nitrate by bacteria isolated from contaminated mine sediments

    Science.gov (United States)

    Terry, Lee R.; Kulp, Thomas R.; Wiatrowski, Heather A.; Miller, Laurence G.; Oremland, Ronald S.

    2015-01-01

    Bacterial oxidation of arsenite [As(III)] is a well-studied and important biogeochemical pathway that directly influences the mobility and toxicity of arsenic in the environment. In contrast, little is known about microbiological oxidation of the chemically similar anion antimonite [Sb(III)]. In this study, two bacterial strains, designated IDSBO-1 and IDSBO-4, which grow on tartrate compounds and oxidize Sb(III) using either oxygen or nitrate, respectively, as a terminal electron acceptor, were isolated from contaminated mine sediments. Both isolates belonged to the Comamonadaceae family and were 99% similar to previously described species. We identify these novel strains as Hydrogenophagataeniospiralis strain IDSBO-1 and Variovorax paradoxus strain IDSBO-4. Both strains possess a gene with homology to the aioA gene, which encodes an As(III)-oxidase, and both oxidize As(III) aerobically, but only IDSBO-4 oxidized Sb(III) in the presence of air, while strain IDSBO-1 could achieve this via nitrate respiration. Our results suggest that expression of aioA is not induced by Sb(III) but may be involved in Sb(III) oxidation along with an Sb(III)-specific pathway. Phylogenetic analysis of proteins encoded by the aioA genes revealed a close sequence similarity (90%) among the two isolates and other known As(III)-oxidizing bacteria, particularly Acidovorax sp. strain NO1. Both isolates were capable of chemolithoautotrophic growth using As(III) as a primary electron donor, and strain IDSBO-4 exhibited incorporation of radiolabeled [14C]bicarbonate while oxidizing Sb(III) from Sb(III)-tartrate, suggesting possible Sb(III)-dependent autotrophy. Enrichment cultures produced the Sb(V) oxide mineral mopungite and lesser amounts of Sb(III)-bearing senarmontite as precipitates.

  9. Orthocomplementation and Compound Systems

    Science.gov (United States)

    Ischi, Boris

    2005-12-01

    In their 1936 founding paper on quantum logic, Birkhoff and von Neumann postulated that the lattice describing the experimental propositions concerning a quantum system is orthocomplemented. We prove that this postulate fails for the lattice mathcal{L} sep describing a compound system consisting of so called separated quantum systems. By separated we mean two systems prepared in different “rooms” of the lab, and before any interaction takes place. In that case, the state of the compound system is necessarily a product state. As a consequence, Dirac’s superposition principle fails, and therefore mathcal{L} sep cannot satisfy all Piron’s axioms. In previous works, assuming that mathcal{L} sep is orthocomplemented, it was argued that mathcal{L} sep is not orthomodular and fails to have the covering property. Here we prove that mathcal{L} sep cannot admit an orthocomplementation. Moreover, we propose a natural model for mathcal{L} sep which has the covering property.

  10. Goldenphilicity: Luminescent gold compounds

    International Nuclear Information System (INIS)

    Sansores, L.E.

    2002-01-01

    In the solids and molecules different types of bonds are presented depending on the involved atoms, covalent bonds are common among elements of open shell, where more bond orbitals are filled than anti bond orbitals. It is expected that ionic bonds among closed shell atoms which have charges of opposite sign. Bonds type Van der Waals are presented among molecules which have a bipolar moment. It would not be expected bonds among zero charge species, or more generally with the same nominal charge and in any case the attractive forces would be very small. In fact it is expected that two metallic cations to be repelled each other. There recently is evidence that in organic or organometallic compounds could exist attractive interactions between two cations of the d 8 -d 10 -s 2 families. These bonds are weak but stronger than those of Van der Waals. They are compared with the hydrogen bonds. In this work it was reviewed some examples in which the goldenphilicity plays an important role in the luminescence that the gold complexes present. Examples of mono, bi and trinuclear and the structures that these organometallic compounds could take are examined. (Author)

  11. Synthesis of labeled compounds

    International Nuclear Information System (INIS)

    Whaley, T.W.

    1977-01-01

    Intermediate compounds labeled with 13 C included methane, sodium cyanide, methanol, ethanol, and acetonitrile. A new method for synthesizing 15 N-labeled 4-ethylsulfonyl-1-naphthalene-sulfonamide was developed. Studies were conducted on pathways to oleic-1- 13 C acid and a second pathway investigated was based on carbonation of 8-heptadecynylmagnesium bromide with CO 2 to prepare sterolic acid. Biosynthetic preparations included glucose- 13 C from starch isolated from tobacco leaves following photosynthetic incubation with 13 CO 2 and galactose- 13 C from galactosylglycerol- 13 C from kelp. Research on growth of organisms emphasized photosynthetic growth of algae in which all cellular carbon is labeled. Preliminary experiments were performed to optimize the growth of Escherichia coli on sodium acetate- 13 C

  12. Volatile organic compounds

    International Nuclear Information System (INIS)

    Silseth, May Liss

    1998-01-01

    The goal is: Not more emission of volatile organic compounds (VOCs) than necessary. The items discussed in this presentation are the VOCs, how to calculate emission of VOCs, how to reduce or avoid them, and different recovery processes. The largest source of Norwegian emissions of non methane VOCs (NMVOCs) is offshore loading of raw petroleum. Emissions of VOCs should be reduced mainly for two reasons: (1) on sunny days NMVOCs may react with NOx to form ozon and smog close to the surface, (2) ozone and smog close to the surface may be harmful to plants and animals, and they are hazardous to human health. As for the calculation of VOC emissions, the VOCON project will release the calculation program HCGASS in 1999. This project is a cooperative project headed by SINTEF/Marintek

  13. Combined effects of antimony and sodium diethyldithiocarbamate on soil microbial activity and speciation change of heavy metals. Implications for contaminated lands hazardous material pollution in nonferrous metal mining areas.

    Science.gov (United States)

    Zhu, Xiaozhe; Yao, Jun; Wang, Fei; Yuan, Zhimin; Liu, Jianli; Jordan, Gyozo; Knudsen, Tatjana Šolević; Avdalović, Jelena

    2018-05-05

    The combined effects of antimony (Sb) and sodium diethyldithiocarbamate (DDTC), a common organic flotation reagent, on soil microbial activity and speciation changes of heavy metals were investigated for the first time. The results showed that the exchangeable fraction of Sb was transformed to a stable residual fraction during the incubation period, and the addition of DDTC promoted the transformation compared with single Sb pollution, probably because DDTC can react with heavy metals to form a complex. In addition, the presence of DDTC and Sb inhibited the soil microbial activity to varying degrees. The growth rate constant k of different interaction systems was in the following order on the 28th day: control group ≥ single DDTC pollution > combined pollution > single Sb pollution. A correlation analysis showed that the concentration of exchangeable Sb was the primary factor that affected the toxic reaction under combined pollution conditions, and it significantly affected the characteristics of the soil microorganisms. All the observations provide useful information for a better understanding of the toxic effects and potential risks of combined Sb and DDTC pollution in antimony mining areas. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Avaliação do efeito cumulativo do antimoniato de meglumina sobre a prole de camundongos swiss: ensaio biológico Evaluate the cumulative effect of meglumine antimoniate on the progeny of swiss mice: biologic assay

    Directory of Open Access Journals (Sweden)

    Michelle Rodrigues dos Santos

    2008-02-01

    Full Text Available OBJETIVOS: Avaliar o efeito do antimoniato de meglumina na transferência materno-fetal na geração F1 (prole de matrizes expostas ao composto, e conseqüências em progênies F2. MÉTODOS: Camundongos fêmeas Swiss foram tratados com antimoniato de meglumina, via subcutânea, com administração diária, do sétimo ao 12º dia de gestação (ddg, na dose equivalente a 100mgSb v/kg peso/dia. O grupo controle recebeu apenas o veículo (água destilada. Após o nascimento da prole (geração F1, 59 fêmeas foram examinadas diariamente para determinação do ciclo estral. Quando determinado o ciclo estro, acasalou-se 18 fêmeas com machos da mesma linhagem. No 18º ddg, as fêmeas foram eutanasiadas por câmara de CO2, o abdômen incisado e o útero exposto, quando avaliou-se os sítios de desenvolvimento embrionário e fetal quanto ao número de reabsorções, fetos vivos e mortos. Todos os fetos e placentas foram pesados para calcular o índice placentário. Três placentas de cada ninhada foram separadas para análise microscópica. RESULTADOS: A exposição ao antimoniato de meglumina não interferiu no ciclo estral dos animais tratados, pelo fato de não alterar o intervalo precoital e o índice de fertilidade. Não foram observadas alterações placentárias em progênies F2. CONCLUSÃO: O antimoniato de meglumina não altera a performance reprodutiva das mães expostas cronicamente. Estes dados sugerem que ocorre uma gradual eliminação do antimoniato de meglumina no organismo materno, sem acarretar danos a proles futuras.OBJECTIVES: Evaluate the effect of Meglumine Antimoniate on maternal-fetal transference in F1 generations (offspring of dams exposed to the drug, and embryotoxicity in F2 generations. METHODS: Female Swiss mice were treated with daily s.c. injection of Meglumine Antimoniate (100mgSb v/kg bw/day from day 7 until day 12 of pregnancy. The control group received only the vehicle (distilled water. After birth of offspring (F1

  15. Pluto's Nonvolatile Chemical Compounds

    Science.gov (United States)

    Grundy, William M.; Binzel, Richard; Cook, Jason C.; Cruikshank, Dale P.; Dalle Ore, Cristina M.; Earle, Alissa M.; Ennico, Kimberly; Jennings, Donald; Howett, Carly; Kaiser, Ralf-Ingo; Linscott, Ivan; Lunsford, A. W.; Olkin, Catherine B.; Parker, Alex Harrison; Parker, Joel Wm.; Philippe, Sylvain; Protopapa, Silvia; Quirico, Eric; Reuter, D. C.; Schmitt, Bernard; Singer, Kelsi N.; Spencer, John R.; Stansberry, John A.; Stern, S. Alan; Tsang, Constantine; Verbiscer, Anne J.; Weaver, Harold A.; Weigle, G. E.; Young, Leslie

    2016-10-01

    Despite the migration of Pluto's volatile ices (N2, CO, and CH4) around the surface on seasonal timescales, the planet's non-volatile materials are not completely hidden from view. They occur in a variety of provinces formed over a wide range of timescales, including rugged mountains and chasms, the floors of mid-latitude craters, and an equatorial belt of especially dark and reddish material typified by the informally named Cthulhu Regio. NASA's New Horizons probe observed several of these regions at spatial resolutions as fine as 3 km/pixel with its LEISA imaging spectrometer, covering wavelengths from 1.25 to 2.5 microns. Various compounds that are much lighter than the tholin-like macromolecules responsible for the reddish coloration, but that are not volatile at Pluto surface temperatures such as methanol (CH3OH) and ethane (C2H6) have characteristic absorption bands within LEISA's wavelength range. This presentation will describe their geographic distributions and attempt to constrain their origins. Possibilities include an inheritance from Pluto's primordial composition (the likely source of H2O ice seen on Pluto's surface) or ongoing production from volatile precursors through photochemistry in Pluto's atmosphere or through radiolysis on Pluto's surface. New laboratory data inform the analysis.This work was supported by NASA's New Horizons project.

  16. Sources, migration and transformation of antimony contamination in the water environment of Xikuangshan, China: Evidence from geochemical and stable isotope (S, Sr) signatures

    Energy Technology Data Exchange (ETDEWEB)

    Wen, Bing [Geological Survey, China University of Geosciences (Wuhan), Lumo Rd 388, Wuhan 430074, Hubei (China); State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences (Wuhan), Lumo Rd 388, Wuhan 430074, Hubei (China); Zhou, Jianwei, E-mail: jw.zhou@cug.edu.cn [School of Environmental Studies, China University of Geosciences (Wuhan), Lumo Rd 388, Wuhan 430074, Hubei (China); Zhou, Aiguo; Liu, Cunfu [School of Environmental Studies, China University of Geosciences (Wuhan), Lumo Rd 388, Wuhan 430074, Hubei (China); Xie, Lina [School of Environmental Studies, China University of Geosciences (Wuhan), Lumo Rd 388, Wuhan 430074, Hubei (China); State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences (Wuhan), Lumo Rd 388, Wuhan 430074, Hubei (China)

    2016-11-01

    The Xikuangshan (XKS) mine in central China is the largest antimony (Sb) mine in the world. The mining activity has seriously contaminated the waters in the area. To determine the sources, migration and transformation of Sb contamination, 32 samples from groundwater (aquifer water), surface water and mine water were collected for water chemistry, trace element and S{sub SO4} and Sr stable isotope analyses. The results showed that the groundwater and surface water were in an oxidized environment. The S{sub SO4} and Sr isotope compositions in the water indicated that dissolved Sb and SO{sub 4}{sup 2} originated from sulfide mineral (Sb{sub 2}S{sub 3}) oxidation, whereas radiogenic Sr may have been sourced from silicified limestone and stibnite in the Shetianqiao aquifer. Furthermore, a positive correlation between δ{sup 34}S{sub SO4} and δ{sup 87}Sr values revealed that the Sr, S and Sb in the waters had a common contamination source, i.e., silicified limestone and stibnite, whereas the Sr, S and Sb in rock and ore were sourced from Proterozoic basement clastics. The analysis also indicated that the isotope composition of dissolved SO{sub 4}{sup 2} {sup −} had been influenced by slight bacterial SO{sub 4} reduction in the Magunao aquifer. Mining or rock collapse may have caused Shetianqiao aquifer water to contaminate the Magunao aquifer water via mixing. This study has demonstrated that the stable isotopes of {sup 34}S{sub SO4} and {sup 87}Sr, combined with hydrochemical methods, are effective in tracking the sources, migration and transformation of Sb contamination. - Highlights: • Mining activities at XKS mine have caused serious water contamination. • The characteristics of Sb contamination in water environment are still unclear. • Combine S isotopes of sulfate and Sr isotopes with hydrochemical methods. • Sr, S, and Sb in natural water had a common source: silicified limestone and stibnite. • Shetianqiao aquifer water contaminated the Magunao

  17. Method of preparing metallocene compounds

    Energy Technology Data Exchange (ETDEWEB)

    Rosenblum, M.; Matchett, S.A.

    1992-06-23

    This invention describes a novel method of preparing metallocene compounds. The invention is based on synthesis of novel bis cyclopentadienides that, under appropriate conditions, will either encapsulate a transition metal to produce a metallocene such as ferrocene, or ferrocene derivative, or will yield a polymeric metallocene. Compounds produced by this process are useful as catalysts in propulsion systems, or as anti-knock compounds in gasolines. 2 figs.

  18. Method of preparing metallocene compounds

    Science.gov (United States)

    Rosenblum, Myron; Matchett, Stephen A.

    1992-01-01

    This invention describes a novel method of preparing metallocene compounds. The invention is based on synthesis of novel bis cyclopentadienides that, under appropriate conditions, will either encapsulate a transition metal to produce a metallocene such as ferrocene, or ferrocene derivative, or will yield a polymeric metallocene. Compounds produced by this process are useful as catalysts in propulsion systems, or as anti-knock compounds in gasolines.

  19. Phenolic compounds in Ecuadorian fruits

    OpenAIRE

    Vasco, Catalina

    2009-01-01

    A group of eighteen fruits cultivated in Ecuador were evaluated for their total soluble phenolic compounds and antioxidant activity and attempts were made to identify the group and content of phenolic compounds responsible for the antioxidant activity. In terms of total phenolic content, three groups (with 1000 mg gallic acid equivalents/100 g FW) were clearly distinguishable. RP-HPLC-DAD and/or LC-MS/MS were used to study the phenolic compounds in four Rosaceae fruits (Andean blackberry, str...

  20. Transition Metal Compounds Towards Holography

    Directory of Open Access Journals (Sweden)

    Volker Dieckmann

    2012-06-01

    Full Text Available We have successfully proposed the application of transition metal compounds in holographic recording media. Such compounds feature an ultra-fast light-induced linkage isomerization of the transition-metal–ligand bond with switching times in the sub-picosecond regime and lifetimes from microseconds up to hours at room temperature. This article highlights the photofunctionality of two of the most promising transition metal compounds and the photophysical mechanisms that are underlying the hologram recording. We present the latest progress with respect to the key measures of holographic media assembled from transition metal compounds, the molecular embedding in a dielectric matrix and their impressive potential for modern holographic applications.

  1. Organic Compounds in Carbonaceous Meteorites

    Science.gov (United States)

    Cooper, Grorge

    2001-01-01

    Carbonaceous meteorites are relatively enriched in soluble organic compounds. To date, these compounds provide the only record available to study a range of organic chemical processes in the early Solar System chemistry. The Murchison meteorite is the best-characterized carbonaceous meteorite with respect to organic chemistry. The study of its organic compounds has related principally to aqueous meteorite parent body chemistry and compounds of potential importance for the origin of life. Among the classes of organic compounds found in Murchison are amino acids, amides, carboxylic acids, hydroxy acids, sulfonic acids, phosphonic acids, purines and pyrimidines (Table 1). Compounds such as these were quite likely delivered to the early Earth in asteroids and comets. Until now, polyhydroxylated compounds (polyols), including sugars (polyhydroxy aldehydes or ketones), sugar alcohols, sugar acids, etc., had not been identified in Murchison. Ribose and deoxyribose, five-carbon sugars, are central to the role of contemporary nucleic acids, DNA and RNA. Glycerol, a three-carbon sugar alcohol, is a constituent of all known biological membranes. Due to the relative lability of sugars, some researchers have questioned the lifetime of sugars under the presumed conditions on the early Earth and postulated other (more stable) compounds as constituents of the first replicating molecules. The identification of potential sources and/or formation mechanisms of pre-biotic polyols would add to the understanding of what organic compounds were available, and for what length of time, on the ancient Earth.

  2. Natural compounds with herbicidal activity

    Directory of Open Access Journals (Sweden)

    Pasquale Montemurro

    2011-02-01

    Full Text Available Research about phytotoxic activity of natural compounds could lead both to find new herbicidal active ingredients and to plan environmental friendly weed control strategies. Particularly, living organisms could be a source of compounds that are impossible, for their complexity, to synthesize artificially. More over, they could have alternative sites of action respect to the known chemical herbicides and, due to their origin, they should be more environmental safe. Many living organism, such as bacteria, fungi, insects, lichens and plants, are able to produce bioactive compounds. They generally are secondary metabolites or simply waste molecules. In this paper we make a review about these compounds, highlighting potential and constraints.

  3. Xenobiotic organic compounds in wastewater

    DEFF Research Database (Denmark)

    Eriksson, Eva; Baun, Anders; Henze, Mogens

    2002-01-01

    hundred of XOCs, among them mainly originating from hygiene products: chlorophenols, detergents and phthalates. Several compounds not deriving from hygiene products were also identified e.g. flame-retardants and drugs. A environmental hazard identification showed that a large number of compounds with high...

  4. Compound-heterozygous Marfan syndrome

    NARCIS (Netherlands)

    van Dijk, F. S.; Hamel, B. C.; Hilhorst-Hofstee, Y.; Mulder, B. J. M.; Timmermans, J.; Pals, G.; Cobben, J. M.

    2009-01-01

    We report two families in which the probands have compound-heterozygous Marfan syndrome (MFS). The proband of family I has the R2726W FBN1 mutation associated with isolated skeletal features on one allele and a pathogenic FBN1 mutation on the other allele. The phenotype of the compound-heterozygous

  5. II-VI semiconductor compounds

    CERN Document Server

    1993-01-01

    For condensed matter physicists and electronic engineers, this volume deals with aspects of II-VI semiconductor compounds. Areas covered include devices and applications of II-VI compounds; Co-based II-IV semi-magnetic semiconductors; and electronic structure of strained II-VI superlattices.

  6. 2. Intermetallic compounds with lanthanides

    International Nuclear Information System (INIS)

    Elemans, J.B.A.A.

    1975-01-01

    Theoretical considerations are given concerning the structures of intermetallic compounds of the lanthanides and thorium (R) on the one hand, and with Fe, Co or Ni (M) on the other. They all derive from the parent composition RM 5 with the CaCu 5 hexagonal structure. This consists of alternate layers in which the M atoms are distinguished as M 1 and M 2 . The other compounds whose structures are studied are obtained by systematic replacement of R by M, or vice versa. In the first type, every third R is replaced by two M's yielding R 2 M 17 compounds. The substitution may be truly random or structured in two ways: so that either the hexagonal structure is maintained or that it is converted into a rhombihedral one. In the second type, one M (in a M 1 position) out of every five is replaced by one R, giving rise to RM 2 compounds which form Laves phases. In the third type, the M 1 's are replaced by R's, resulting in compounds RM 3 . In the fourth type, every third M is replaced by R, yielding R 2 M 7 compounds. With M = Co and R a light lanthanide, the compounds are ferromagnets; with R yttrium, thorium, or a heavy lanthanide, they are ferrimagnets. The preparation of the compounds in an arc-melting apparatus under an Ar-atmosphere followed by annealing is described

  7. The demise of compound houses

    DEFF Research Database (Denmark)

    Andreasen, Jørgen; Eskemose Andersen, Jørgen

    2006-01-01

    The compound house has long provided the accomodation required by low income households in West African cities. In Kumasi, Ghana, evidence suggests that no new compounds are being built. Instead, the city is being ringed by relatively affluent villa-style development while neighbourhoods dominated...

  8. METHOD OF REDUCING PLUTONIUM COMPOUNDS

    Science.gov (United States)

    Johns, I.B.

    1958-06-01

    A method is described for reducing plutonium compounds in aqueous solution from a higher to a lower valence state. This reduction of valence is achieved by treating the aqueous solution of higher valence plutonium compounds with hydrogen in contact with an activated platinum catalyst.

  9. Complex chemistry with complex compounds

    Directory of Open Access Journals (Sweden)

    Eichler Robert

    2016-01-01

    Full Text Available In recent years gas-phase chemical studies assisted by physical pre-separation allowed for the investigation of fragile single molecular species by gas-phase chromatography. The latest success with the heaviest group 6 transactinide seaborgium is highlighted. The formation of a very volatile hexacarbonyl compound Sg(CO6 was observed similarly to its lighter homologues molybdenum and tungsten. The interactions of these gaseous carbonyl complex compounds with quartz surfaces were investigated by thermochromatography. Second-generation experiments are under way to investigate the intramolecular bond between the central metal atom of the complexes and the ligands addressing the influence of relativistic effects in the heaviest compounds. Our contribution comprises some aspects of the ongoing challenging experiments as well as an outlook towards other interesting compounds related to volatile complex compounds in the gas phase.

  10. First flush of dissolved compounds

    DEFF Research Database (Denmark)

    Krebs, P.; Holzer, P.; Huisman, J.L.

    1999-01-01

    In a crude conceptual approach it is commonly assumed that in a combined sewer system the concentration of dissolved compounds is diluted by an increasing flow rate due to rainwater inflow. However, theory of hydraulics suggests that these compounds are influenced by hydrodynamic effects. It is k......In a crude conceptual approach it is commonly assumed that in a combined sewer system the concentration of dissolved compounds is diluted by an increasing flow rate due to rainwater inflow. However, theory of hydraulics suggests that these compounds are influenced by hydrodynamic effects....... It is known that since the wave celerity is higher than the flow velocity of the water, the increase of flow rate induced through rain runoff is recognised earlier at a certain downstream section of the combined sewer than the concentration increase of typical rain-water compounds originating from surface...

  11. Efeito de uma formulação hidrofílica de paromomicina tópica na leishmaniose cutânea em pacientes com contra-indicações de tratamento com antimonial pentavalente Effect of a hydrophilic formulation of topical paromomycin on cutaneous leishmaniasis among patients with contraindications for treatment with pentavalent antimonials

    Directory of Open Access Journals (Sweden)

    Aline Marques dos Santos

    2008-10-01

    Full Text Available Descrevem-se o efeito terapêutico e os eventos adversos associados com o uso tópico de paromomicina 10% em gel na leishmaniose cutânea. Quinze pacientes com leishmaniose cutânea cumpriram os critérios de inclusão descritos a seguir: contra-indicação para o uso de antimoniato de meglumina, intradermorreação de Montenegro positiva e até quatro lesões ulceradas. A fórmula foi prescrita duas vezes ao dia por 20 dias. Quatorze pacientes estiveram disponíveis para a avaliação do desfecho terapêutico e a proporção de cura foi de 21,4% (3/14, 50% melhoraram até a epitelização completa e a proporção de falha foi de 28,6%. Nove pacientes que não apresentaram cura inicialmente foram re-tratados. Oito receberam uma nova série de paromomicina tópica e um foi tratado com antimoniato de meglumina. Dois pacientes não receberam novo tratamento e tiveram melhora lenta e contínua. Cinco de oito pacientes retratados com paromomicina tópica alcançaram a cura clínica, e três apresentaram falha, incluindo um paciente que tinha apresentado melhora com o primeiro tratamento. Os eventos adversos foram leves e locais em 53,3% dos pacientes e nunca levaram à suspensão do tratamento.The therapeutic effect of and adverse events associated with topical use of 10% paromomycin gel on cutaneous leishmaniasis are described. Fifteen patients with cutaneous leishmaniasis fulfilled the following inclusion criteria: contraindication for the use of meglumine antimoniate, positive Montenegro skin test and up to four ulcerated lesions. The formula was prescribed twice a day for 20 days. Fourteen patients were available for the therapeutic outcome evaluation. The cure rate was 21.4% (3/14; 50% improved as far as complete epithelialization; and the failure rate was 28.6%. Nine patients who did not initially present cure were retreated. Eight received a new series of topical paromomycin and one was treated with meglumine antimoniate. Two patients did not

  12. EPR investigations on technetium compounds

    International Nuclear Information System (INIS)

    Abram, U.; Munze, R.; Kirmse, R.; Stach, J.

    1986-01-01

    Stimulated by the widespread use of the isotope /sup 99m/Tc in the field of nuclear medicine, there has been a substantial growth of interest in the chemistry of this man-made element. A particular need emerges for analytical methods allowing solution investigations of coordination compounds of technetium with low substance use. Considering these facts, Electron Paramagnetic Resonance Spectroscopy (EPR) appears to be a very suitable method because only very small amounts of the compounds are needed (lower than 1 mg). The resulting spectra give information regarding the valence state, symmetry and bonding properties of the compounds under study

  13. Vapor Pressure of Antimony Triiodide

    Science.gov (United States)

    2017-12-07

    Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law , no person shall be...has little consequence on doping. However, substitutional I on a tellurium (Te) site will serve as a singly ionized donor, and in the case of I on a...Bi or Sb site, will act as a doubly ionized donor. In either of those cases , substitutional I causes n-type conduction. The growth of epitaxial

  14. Matrix digestion of soil and sediment samples for extraction of lead, cadmium and antimony and their direct determination by inductively coupled plasma-mass spectrometry and atomic emission spectrometry

    International Nuclear Information System (INIS)

    Chattopadhyay, P.; Fisher, A.S.; Henon, D.N.; Hill, S.J.

    2004-01-01

    An environmentally friendly and simple method has been developed for complete digestion of lead, cadmium and antimony from soil samples using a magnesium nitrate assisted dry ashing procedure. Statistical data for a series of experiments with standard reference materials are presented, and precision values are found to be comparable for inductively coupled plasma-mass spectrometry and for inductively coupled plasma-atomic emission spectrometry. From a single digest solution all analytes are quantified without involving any preconcentration routes. Inter-method comparison of inductively coupled plasma-mass spectrometry (ICP-MS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES) shows that the probability of the results being different is less than 99 %. (author)

  15. Assessment of femoral head vascularity by technetium-99m antimony colloid bone marrow imaging within 24 hours of subcapital fracture: a prospective study of 30 patients followed for 2 years

    International Nuclear Information System (INIS)

    Turner, J.H.

    1982-01-01

    The rationale of preoperative imaging of bone marrow was based upon the demonstration of histochemical abnormalities secondary to ischaemia which first become apparent in marrow cells of the femoral head following interruption of the blood supply by subcapital fracture. These marrow abnormalities predate changes in bone cells by several days and may explain the absence of abnormality on conventional bone scans performed on avascular femoral heads within 24 hours of subcapital fracture. The use of an endoprosthesis for fresh femoral neck fractures in unselected patients results in high mortality, high infection rate, high incidence of thromboembolic disease and poor long term results. The successful prediction of avascular necrosis in 92% of 28 patients with active bone marrow in the femoral head in this study is sufficiently accurate to allow appropriate selection of patients for internal fixation or primary prosthetic replacement on the basis of preoperative Tc-99m antimony colloid imaging

  16. The demise of compound houses

    DEFF Research Database (Denmark)

    Andreasen, Jørgen; Eskemose Andersen, Jørgen

    2006-01-01

    of compound housing and analyses the advantages and disadvantages of life within such housing in Kumasi. Issues of privacy, image and communal life are usually cited by occupants dissatiesfied with life in compound houses, and the difficulty of extending them without spoiling the open spaces...... perceptions of what is acceptable urban life to the growing cohort of young African households. In addition, there is a need to explore innovative forms of tenure in order to secure the majority of Kumasi's population access to land for housing.......The compound house has long provided the accomodation required by low income households in West African cities. In Kumasi, Ghana, evidence suggests that no new compounds are being built. Instead, the city is being ringed by relatively affluent villa-style development while neighbourhoods dominated...

  17. Phenolic Compounds in Brassica Vegetables

    Directory of Open Access Journals (Sweden)

    Pablo Velasco

    2010-12-01

    Full Text Available Phenolic compounds are a large group of phytochemicals widespread in the plant kingdom. Depending on their structure they can be classified into simple phenols, phenolic acids, hydroxycinnamic acid derivatives and flavonoids. Phenolic compounds have received considerable attention for being potentially protective factors against cancer and heart diseases, in part because of their potent antioxidative properties and their ubiquity in a wide range of commonly consumed foods of plant origin. The Brassicaceae family includes a wide range of horticultural crops, some of them with economic significance and extensively used in the diet throughout the world. The phenolic composition of Brassica vegetables has been recently investigated and, nowadays, the profile of different Brassica species is well established. Here, we review the significance of phenolic compounds as a source of beneficial compounds for human health and the influence of environmental conditions and processing mechanisms on the phenolic composition of Brassica vegetables.

  18. Fourth symposium on macrocyclic compounds

    International Nuclear Information System (INIS)

    Christensen, J.J.; Izatt, R.M.

    1980-01-01

    Both theoretical and experimental aspects of the properties and behavior of synthetic and naturally occurring macrocyclic compounds are covered in this symposium. This document contains abstracts of the papers

  19. Enzymatic synthesis of organophosphorus compounds

    International Nuclear Information System (INIS)

    Kolodiazhnyi, Oleg I

    2011-01-01

    Data on biocatalytic methods for the preparation of chiral organophosphorus compounds are generalized and described systematically. Various examples of enzymatic and microbiological synthesis of hydroxyphosphonates, aminophosphonates, phosphinites, phosphine oxides and tertiary phosphines are discussed. The bibliography includes 154 references.

  20. Radiation curable hydantoin diacrylate compounds

    International Nuclear Information System (INIS)

    Seltzer, R.; DiPrima, J.F.

    1979-01-01

    The diacrylate compounds are liquid at room temperature, easily processable as adhesives, casting and laminating resins and when cured possess excellent resistance to water. These compositions are easily cured exposure to ionizing radiations

  1. Third Symposium on Macrocyclic Compounds

    International Nuclear Information System (INIS)

    1979-01-01

    At the Third Symposium on Macrocyclic Compounds there were sessions on facilitated transport, analytical applications, organic synthesis and reactions, phase transfer catalysis, and metal complexation. Abstracts of the individual presentations are included

  2. Crystallographic properties of fertilizer compounds

    Energy Technology Data Exchange (ETDEWEB)

    Frazier, A.W.; Dillard, E.F.; Thrasher, R.D.; Waerstad, K.R.; Hunter, S.R.; Kohler, J.J.; Scheib, R.M.

    1991-02-01

    This bulletin is a compilation of crystallographic data collected at NFERC on 450 fertilizer-related compounds. In TVA's fertilizer R and D program, petrographic examination, XRD, and infrared spectroscopy are combined with conventional chemical analysis methods in identifying the individual compounds that occur in fertilizer materials. This handbook brings together the results of these characterization studies and supplemental crystallographic data from the literature. It is in one-compound-per-page, loose-leaf format, ordered alphabetically by IUPAC name. Indexes provided include IUPAC name, formula, group, alternate formula, synonyms, x-ray data, optical data. Tables are given for solids, compounds in commercial MAP and DAP, and matrix materials in phosphate rock.

  3. Quality control of labelled compounds

    International Nuclear Information System (INIS)

    Matucha, M.

    1979-01-01

    Some advantages and disadvantages of methods used for quality control of organic labelled compounds (1 31 I, 14 C) are shortly discussed. The methods used are electrophoresis, ultraviolet and infrared spectrometry, radiogas and thin-layer chromatography. (author)

  4. The precipitation of vanadium compounds

    International Nuclear Information System (INIS)

    Martins, A.H.; Cassa, J.C.S.

    1987-01-01

    The results of a study on the chemistry of the precipitation process of vanadium compounds in sulfuric media are presented, in order to recover the vanadium contained in the ore from Campo Alegre de Lourdes (Bahia-Brazil). (Author) [pt

  5. Enzymatic synthesis of organophosphorus compounds

    Science.gov (United States)

    Kolodiazhnyi, Oleg I.

    2011-09-01

    Data on biocatalytic methods for the preparation of chiral organophosphorus compounds are generalized and described systematically. Various examples of enzymatic and microbiological synthesis of hydroxyphosphonates, aminophosphonates, phosphinites, phosphine oxides and tertiary phosphines are discussed. The bibliography includes 154 references.

  6. Compounding in synthetic aperture imaging

    DEFF Research Database (Denmark)

    Hansen, J. M.; Jensen, J. A.

    2012-01-01

    from multiple spherical emissions to synthesize multiple transmit and receive apertures, corresponding to imaging the tissue from multiple directions. The many images are added incoherently, to produce a single compound image. Using a 192-element, 3.5-MHz, λ-pitch transducer, it is demonstrated from...... tissue-phantom measurements that the speckle is reduced and the contrast resolution improved when applying synthetic aperture compound imaging. At a depth of 4 cm, the size of the synthesized apertures is optimized for lesion detection based on the speckle information density. This is a performance...... measure for tissue contrast resolution which quantifies the tradeoff between resolution loss and speckle reduction. The speckle information density is improved by 25% when comparing synthetic aperture compounding to a similar setup for compounding using dynamic receive focusing. The cystic resolution...

  7. Phenolic Compounds in Brassica Vegetables

    OpenAIRE

    Cartea González, María Elena; Francisco Candeira, Marta; Soengas Fernández, María del Pilar; Velasco Pazos, Pablo

    2011-01-01

    Phenolic compounds are a large group of phytochemicals widespread in the plant kingdom. Depending on their structure they can be classified into simple phenols, phenolic acids, hydroxycinnamic acid derivatives and flavonoids. Phenolic compounds have received considerable attention for being potentially protective factors against cancer and heart diseases, in part because of their potent antioxidative properties and their ubiquity in a wide range of commonly consumed foods of plant origin. The...

  8. The Censor Compound Design Pattern

    DEFF Research Database (Denmark)

    Top, Søren; Jørgensen, Bo Nørregaard; Angelov, Christo K.

    2002-01-01

    "Censor compound design pattern" er et system af design mønstre, som tilsammen giver en løsning på at håndtere ikke funktionelle hensyn i programkoden......"Censor compound design pattern" er et system af design mønstre, som tilsammen giver en løsning på at håndtere ikke funktionelle hensyn i programkoden...

  9. Crystal, magnetic, calorimetric and electronic structure investigation of GdScGe1–x Sb x compounds

    Science.gov (United States)

    Guillou, F.; Pathak, A. K.; Hackett, T. A.; Paudyal, D.; Mudryk, Y.; Pecharsky, V. K.

    2017-12-01

    Experimental investigations of crystal structure, magnetism and heat capacity of compounds in the pseudoternary GdScGe-GdScSb system combined with density functional theory projections have been employed to clarify the interplay between the crystal structure and magnetism in this series of RTX materials (R  =  rare-earth, T   =  transition metal and X  =  p-block element). We demonstrate that the CeScSi-type structure adopted by GdScGe and CeFeSi-type structure adopted by GdScSb coexist over a limited range of compositions 0.65 ≤slant x ≤slant 0.9 . Antimony for Ge substitutions in GdScGe result in an anisotropic expansion of the unit cell of the parent that is most pronounced along the c axis. We believe that such expansion acts as the driving force for the instability of the double layer CeScSi-type structure of the parent germanide. Extensive, yet limited Sb substitutions 0 ≤slant x disappearance of the induced magnetic moments on Sc. For the parent antimonide, heat capacity measurements indicate an additional transition below the main antiferromagnetic transition.

  10. Compound Odontoma in young girl

    Directory of Open Access Journals (Sweden)

    Nurwahida Nurwahida

    2017-08-01

    Full Text Available Introduction. Odontomas are the most common type of odontogenic tumors and generally they are asymptomatic. These tumors are formed from enamel and dentin, and can have variable amounts of cement and pulp tissues. According to radiographic, microscopic, and clinical features, two types of odontomas are recognized: Complex and compound odontomas. Complex odontomas occur mostly in the posterior part of the mandible and compound odontomas in the anterior maxilla. Case Report. A young girl patient, 9 years old came to Department of Oral and Maxillofacial Surgery with a slow growing and asymptomatic swelling in her left posterior mandible for 5 years in his history taking. The panoramic radiograph show  a radioopacity and radiolucent lesion at the lower second molar region, with well-corticated limits. An insisional biopsi   confirmed  as compound odontoma. The surgery  performed with simple enucleation and curettage under general anaesthesia. Discussion. Compound odontomas are usually located in the anterior maxilla, over the crowns of unerupted teeth, or between the roots of erupted teeth. In this case report, Compound odontomas are found in the posterior mandible. Conclusion. Compound odontomas in the posterior mandible is a rare. The treatment of odontomas depends on the size of the lesion. The early diagnosis, the treatment of choice is conservative surgical enucleation and curettage and prognosis is excellent.

  11. Host compounds for red phosphorescent OLEDs

    Energy Technology Data Exchange (ETDEWEB)

    Xia, Chuanjun; Cheon, Kwang -Ohk

    2015-08-25

    Novel compounds containing a triphenylene moiety linked to an .alpha..beta. connected binaphthyl ring system are provided. These compounds have surprisingly good solubility in organic solvents and are useful as host compounds in red phosphorescent OLEDs.

  12. Promiscuity progression of bioactive compounds over time

    OpenAIRE

    Hu, Ye; Jasial, Swarit; Bajorath, J?rgen

    2015-01-01

    In the context of polypharmacology, compound promiscuity is rationalized as the ability of small molecules to specifically interact with multiple targets. To study promiscuity progression of bioactive compounds in detail, nearly 1 million compounds and more than 5.2 million activity records were analyzed. Compound sets were assembled by applying different data confidence criteria and selecting compounds with activity histories over many years. On the basis of release dates, compounds and acti...

  13. Vanadium Compounds as PTP Inhibitors

    Directory of Open Access Journals (Sweden)

    Elsa Irving

    2017-12-01

    Full Text Available Phosphotyrosine signaling is regulated by the opposing actions of protein tyrosine kinases (PTKs and protein tyrosine phosphatases (PTPs. Here we discuss the potential of vanadium derivatives as PTP enzyme inhibitors and metallotherapeutics. We describe how vanadate in the V oxidized state is thought to inhibit PTPs, thus acting as a pan-inhibitor of this enzyme superfamily. We discuss recent developments in the biological and biochemical actions of more complex vanadium derivatives, including decavanadate and in particular the growing number of oxidovanadium compounds with organic ligands. Pre-clinical studies involving these compounds are discussed in the anti-diabetic and anti-cancer contexts. Although in many cases PTP inhibition has been implicated, it is also clear that many such compounds have further biochemical effects in cells. There also remain concerns surrounding off-target toxicities and long-term use of vanadium compounds in vivo in humans, hindering their progress through clinical trials. Despite these current misgivings, interest in these chemicals continues and many believe they could still have therapeutic potential. If so, we argue that this field would benefit from greater focus on improving the delivery and tissue targeting of vanadium compounds in order to minimize off-target toxicities. This may then harness their full therapeutic potential.

  14. Cytotoxic Compounds from Brucea mollis

    Directory of Open Access Journals (Sweden)

    Mai Hung Thanh TUNG

    2016-09-01

    Full Text Available Ten compounds, including soulameanone (1, isobruceine B (2, 9-methoxy-canthin-6-one (3, bruceolline F (4, niloticine (5, octatriacontan-1-ol (6, bombiprenone (7, α-tocopherol (8, inosine (9, and apigenin 7-O-β-D-glucopyranoside (10, were isolated from the leaves, stems, and roots of Brucea mollis Wall. ex Kurz. Their structures were determined using one- and two-dimensional NMR spectroscopy and mass spectrometry. All compounds were evaluated for their cytotoxic activity against KB (human carcinoma of the mouth, LU-1 (human lung adenocarcinoma, LNCaP (human prostate adeno-carcinoma, and HL-60 (human promyelocytic leukemia cancer cell lines. Compound 2 showed significant cytotoxic activity against KB, LU-1, LNCaP, and HL-60 cancer cells with IC50 values of 0.39, 0.40, 0.34, and 0.23 μg/mL, respectively. In addition, compounds 3 and 5 showed significant cytotoxic activity against KB, LU-1, LNCaP, and HL-60 cancer cells with IC50 values around 1–4 μg/mL. Compounds 9-methoxycanthin-6-one (3 and niloticine (5 have been discovered for the first time from the Brucea genus.

  15. Extraterrestrial Organic Compounds in Meteorites

    Science.gov (United States)

    Botta, Oliver; Bada, Jeffrey L.; Meyer, Michael (Technical Monitor)

    2003-01-01

    Many organic compounds or their precursors found in meteorites originated in the interstellar or circumstellar medium and were later incorporated into planetesimals during the formation of the solar system. There they either survived intact or underwent further processing to synthesize secondary products on the meteorite parent body. The most distinct feature of CI and CM carbonaceous chondrites, two types of stony meteorites, is their high carbon content (up to 3% of weight), either in the form of carbonates or of organic compounds. The bulk of the organic carbon consists of an insoluble macromolecular material with a complex structure. Also present is a soluble organic fraction, which has been analyzed by several separation and analytical procedures. Low detection limits can be achieved by derivatization of the organic molecules with reagents that allow for analysis by gas chromatography/mass spectroscopy and high performance liquid chromatography. The CM meteorite Murchison has been found to contain more than 70 extraterrestrial amino acids and several other classes of compounds including carboxylic acids, hydroxy carboxylic acids, sulphonic and phosphonic acids, aliphatic, aromatic and polar hydrocarbons, fullerenes, heterocycles as well as carbonyl compounds, alcohols, amines and amides. The organic matter was found to be enriched in deuterium, and distinct organic compounds show isotopic enrichments of carbon and nitrogen relative to terrestrial matter.

  16. Compound Words In Dawan Language

    Directory of Open Access Journals (Sweden)

    I Wayan Budiarta

    2016-04-01

    Full Text Available The purpose of this study is to find out the structure of compound words and the types of compound words in Dawan language. This study belongs to qualitative research as it aimed to describe qualitatively the structure and the types of compound words in Dawan language. The data are taken from language consultants (informants of Dawan language speaker. In collecting the data, the researcher prepares questionnaire and applied interview method. The result of analysis showed that compound words in Dawan language are structured by combining two different words whether the words in the same category or different category. The structure of compound words are built by combining noun (N with noun (N, for instance mais-oni ‘sugar’ which is built by the noun mais ‘salt’ and the noun oni ‘sweet’; noun (N with verb (V, for instnace bife-anaot ‘prostitute’ which is built by the noun bife ‘woman’ and the verb anaot ‘work’; verb (V with noun (N, for instance poni-haano ‘propose’ which is built by the verb poni ‘hang’ and the noun hauno ‘leaf’; verb (V with verb (V, for instance fua-tulu ‘worship’ which is built by the verb fua ‘see’ and the verb tulu ‘give’; and noun (N with adjective (Adj, for instance ume-kbubu ‘kitchen’ which is built by the noun ume ‘house’ and the adjective kbubu ‘circle’. Further analysis on the compound words showed that they can also be classified into noun head word, verb head word, and adjective head word.

  17. Antiprotozoal compounds from Asparagus africanus

    DEFF Research Database (Denmark)

    Oketch-Rabah, H A; Dossaji, S F; Christensen, S B

    1997-01-01

    Two antiprotozoal compounds have been isolated from the roots of Asparagus africanus Lam. (Liliaceae), a new sapogenin, 2 beta, 12 alpha-dihydroxy-(25R)-spirosta-4,7-dien-3-one (1), which was named muzanzagenin, and the lignan (+)-nyasol (2), (Z)-(+)-4,4'-(3-ethenyl-1-propene-1,3-diyl)-bisphenol.......Two antiprotozoal compounds have been isolated from the roots of Asparagus africanus Lam. (Liliaceae), a new sapogenin, 2 beta, 12 alpha-dihydroxy-(25R)-spirosta-4,7-dien-3-one (1), which was named muzanzagenin, and the lignan (+)-nyasol (2), (Z)-(+)-4,4'-(3-ethenyl-1-propene-1,3-diyl...

  18. The structures of binary compounds

    CERN Document Server

    Hafner, J; Jensen, WB; Majewski, JA; Mathis, K; Villars, P; Vogl, P; de Boer, FR

    1990-01-01

    - Up-to-date compilation of the experimental data on the structures of binary compounds by Villars and colleagues. - Coloured structure maps which order the compounds into their respective structural domains and present for the first time the local co-ordination polyhedra for the 150 most frequently occurring structure types, pedagogically very helpful and useful in the search for new materials with a required crystal structure. - Crystal co-ordination formulas: a flexible notation for the interpretation of solid-state structures by chemist Bill Jensen. - Recent important advances in unders

  19. Vanadium compounds as insulin mimics.

    Science.gov (United States)

    Orvig, C; Thompson, K H; Battell, M; McNeill, J H

    1995-01-01

    That vanadium compounds act in an insulin-mimetic fashion both in vitro and in vivo has been well established. Both inorganic and organic vanadium compounds have been shown to lower plasma glucose levels, increase peripheral glucose uptake, improve insulin sensitivity, decrease plasma lipid levels, and normalize liver enzyme activities in a variety of animal models of both type I and type II diabetes. Vanadium treatment of diabetic animals does not restore plasma insulin levels but may spare pancreatic insulin. Elucidation of the mechanism(s) of action and potentiation of vanadium's insulin-mimetic effect by appropriate ligand binding would seem to be the highest priorities for future investigation.

  20. Cytotoxic Compounds from Aloe megalacantha

    Directory of Open Access Journals (Sweden)

    Negera Abdissa

    2017-07-01

    Full Text Available Phytochemical investigation of the ethyl acetate extract of the roots of Aloe megalacantha led to the isolation of four new natural products—1,8-dimethoxynepodinol (1, aloesaponarin III (2, 10-O-methylchrysalodin (3 and methyl-26-O-feruloyl-oxyhexacosanate (4—along with ten known compounds. All purified metabolites were characterized by NMR, mass spectrometric analyses and comparison with literature data. The isolates were evaluated for their cytotoxic activity against a human cervix carcinoma cell line KB-3-1 and some of them exhibited good activity, with aloesaponarin II (IC50 = 0.98 µM being the most active compound.

  1. Catalytic applications of niobium compounds

    International Nuclear Information System (INIS)

    Wright, C.J.; England, W.A.

    1984-01-01

    This article examines the potential uses of niobium, and its compounds, as catalysts in chemical processing. The word potential is deliberately chosen because in 1978 none of the world's twenty-five major catalysts (1) contained niobium. On the other hand, catalysts containing molybdenum and vanadium, neighbors of niobium in the periodic table, realized over 80 x 10 6 of sales in that same year. At the same time many of the patents for niobium catalysts cover applications in which niobium improves the activity of, or substitutes for, molybdenum based compounds. With favorable cost differentials and improvements in understanding, niobium may be able to replace molybdenum in some its traditional uses

  2. Compound

    Indian Academy of Sciences (India)

    Selen Bilgea,*, Zeynel Kılıça, Zeliha Hayvalıa, Tuncer Hökelekb and Serap Safranb. aDepartment of Chemistry, Faculty of Science, Ankara University, Tandoğan, Ankara 06100, Turkey. bDepartment of Physics, Hacettepe University, Beytepe, Ankara 06800, Turkey. e-mail: sbilge@science.ankara.edu.tr. Contents: Tables.

  3. Compound

    Indian Academy of Sciences (India)

    A: in CDCl3, B: in DMSO, a) keto-amine, b) phenol-imine form. * Solubility in CDCl3 and/ or DMSO is not enough for recording 13C NMR spectrum. Table S3. 1H and 13C NMR spectral data of Schiff bases (9 and 13).

  4. Students' Categorizations of Organic Compounds

    Science.gov (United States)

    Domin, Daniel S.; Al-Masum, Mohammad; Mensah, John

    2008-01-01

    Categorization is a fundamental psychological ability necessary for problem solving and many other higher-level cognitive tasks. In organic chemistry, students must establish groupings of different chemical compounds in order not only to solve problems, but also to understand course content. Classic models of categorization emphasize similarity as…

  5. Antifouling Compounds from Marine Macroalgae.

    Science.gov (United States)

    Dahms, Hans Uwe; Dobretsov, Sergey

    2017-08-28

    Marine macroalgae produce a wide variety of biologically-active metabolites that have been developed into commercial products, such as antibiotics, immunosuppressive, anti-inflammatory, cytotoxic agents, and cosmetic products. Many marine algae remain clean over longer periods of time, suggesting their strong antifouling potential. Isolation of biogenic compounds and the determination of their structure could provide leads for the development of environmentally-friendly antifouling paints. Isolated substances with potent antifouling activity belong to fatty acids, lipopeptides, amides, alkaloids, lactones, steroids, terpenoids, and pyrroles. It is unclear as yet to what extent symbiotic microorganisms are involved in the synthesis of these compounds. Algal secondary metabolites have the potential to be produced commercially using genetic and metabolic engineering techniques. This review provides an overview of publications from 2010 to February 2017 about antifouling activity of green, brown, and red algae. Some researchers were focusing on antifouling compounds of brown macroalgae, while metabolites of green algae received less attention. Several studies tested antifouling activity against bacteria, microalgae and invertebrates, but in only a few studies was the quorum sensing inhibitory activity of marine macroalgae tested. Rarely, antifouling compounds from macroalgae were isolated and tested in an ecologically-relevant way.

  6. Coordination Compounds in Biology R

    Indian Academy of Sciences (India)

    naturally occurring organometallic compound found in biology. An intriguing aspect of vitamin Bl2 is the great stability of the metal-carbon bond. A great deal of new and interesting inorganic chemistry has been uncoveredwhlle studying systems pertinent to BI2• In this article some salient features of this unique molecule (B.

  7. Moessbauer spectroscopy in neptunium compounds

    Energy Technology Data Exchange (ETDEWEB)

    Nakamoto, Tadahiro; Nakada, Masami; Masaki, Nobuyuki; Saeki, Masakatsu [Japan Atomic Energy Research Inst., Tokyo (Japan)

    1997-03-01

    Moessbauer effects are observable in seven elements of actinides from {sup 232}Th to {sup 247}Cm and Moesbauer spectra have been investigated mainly with {sup 237}Np and {sup 238}U for the reasons of availability and cost of materials. This report describes the fundamental characteristics of Moessbauer spectra of {sup 237}Np and the correlation between the isomer shift and the coordination number of Np(V) compounds. The isomer shifts of Np(V) compounds had a tendency to increase as an increase of coordination number and the isomer shifts of Np(V) compounds showed broad distribution as well as those of Np(VI) but {delta} values of the compounds with the same coordination number were distributed in a narrow range. The {delta} values of Np(VI) complexes with O{sub x} donor set suggest that the Np atom in its hydroxide (NpO{sub 2}(OH){center_dot}4H{sub 2}O)might have pentagonal bipyramidal structure and at least, pentagonal and hexagonal bipyramidal structures might coexist in its acetate and benzoate. Really, such coexistence has been demonstrated in its nitrate, (NpO{sub 2}){sub 2}(NO{sub 3}){sub 2}{center_dot}5H{sub 2}O. (M.N.)

  8. Bacterial degradation of fluorinated compounds

    NARCIS (Netherlands)

    Ferreira, Maria Isabel Martins

    2007-01-01

    Fluorine was produced for the first time by Henri Moissan in 1886, for which he received the Nobel Prize in chemistry in 1906. The unique properties of fluorine have led to the development of fluorine chemistry and numerous synthetic fluorinated compounds have been prepared and tested for different

  9. Coherent compounding in doppler imaging.

    Science.gov (United States)

    Ekroll, Ingvild K; Voormolen, Marco M; Standal, Oyvind K-V; Rau, Jochen M; Lovstakken, Lasse

    2015-09-01

    Coherent compounding can provide high frame rates and wide regions of interest for imaging of blood flow. However, motion will cause out-of-phase summation, potentially causing image degradation. In this work the impact of blood motion on SNR and the accuracy of Doppler velocity estimates are investigated. A simplified model for the compounded Doppler signal is proposed. The model is used to show that coherent compounding acts as a low-pass filter on the coherent compounding Doppler signal, resulting in negatively biased velocity estimates. Simulations and flow phantom experiments are used to quantify the bias and Doppler SNR for different velocities and beam-to-flow (BTF) angles. It is shown that the bias in the mean velocity increases with increasing beam-to-flow angle and/or blood velocity, whereas the SNR decreases; losses up to 4 dB were observed in the investigated scenarios. Further, a 2-D motion correction scheme is proposed based on multi-angle vector Doppler velocity estimates. For a velocity of 1.1 v(Nyq) and a BTF angle of 75°, the bias was reduced from 30% to less than 4% in simulations. The motion correction scheme was also applied to flow phantom and in vivo recordings, in both cases resulting in a substantially reduced mean velocity bias and an SNR less dependent on blood velocity and direction.

  10. Use of labeled compounds in tracer experiments

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    The use of radiotracers in research has become common. This chapter looks at some of the underlying assumptions and advantages of labeled compounds: advantages of radiotracers; availability of suitable tracers and labeled compounds; purity of labeled compounds; autoradiolysis; storage of labeled compounds; detection systems for chromatography and electrophoretic methods. 14 refs., 2 figs

  11. The nature of compounds: a psychocentric perspective.

    Science.gov (United States)

    Libben, Gary

    2014-01-01

    Although compound words often seem to be words that themselves contain words, this paper argues that this is not the case for the vast majority of lexicalized compounds. Rather, it is claimed that as a result of acts of lexical processing, the constituents of compound words develop into new lexical representations. These representations are bound to specific morphological roles and positions (e.g., head, modifier) within a compound word. The development of these positionally bound compound constituents creates a rich network of lexical knowledge that facilitates compound processing and also creates some of the well-documented patterns in the psycholinguistic and neurolinguistic study of compounding.

  12. Flight dynamics investigation of compound helicopter configurations

    OpenAIRE

    Ferguson, Kevin; Thomson, Douglas

    2015-01-01

    Compounding has often been proposed as a method to increase the maximum speed of the helicopter. There are\\ud two common types of compounding known as wing and thrust compounding. Wing compounding offloads the\\ud rotor at high speeds delaying the onset of retreating blade stall, hence increasing the maximum achievable speed,\\ud whereas with thrust compounding, axial thrust provides additional propulsive force. There has been a resurgence\\ud of interest in the configuration due to the emergenc...

  13. Alkylation of organic aromatic compounds

    Science.gov (United States)

    Smith, L.A. Jr.

    1989-07-18

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C[sub 2] to C[sub 10] olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80 C to 500 C, using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms. 1 fig.

  14. Sweetness prediction of natural compounds.

    Science.gov (United States)

    Chéron, Jean-Baptiste; Casciuc, Iuri; Golebiowski, Jérôme; Antonczak, Serge; Fiorucci, Sébastien

    2017-04-15

    Based on the most exhaustive database of sweeteners with known sweetness values, a new quantitative structure-activity relationship model for sweetness prediction has been set up. Analysis of the physico-chemical properties of sweeteners in the database indicates that the structure of most potent sweeteners combines a hydrophobic scaffold functionalized by a limited number of hydrogen bond sites (less than 4 hydrogen bond donors and 10 acceptors), with a moderate molecular weight ranging from 350 to 450g·mol -1 . Prediction of sweetness, bitterness and toxicity properties of the largest database of natural compounds have been performed. In silico screening reveals that the majority of the predicted natural intense sweeteners comprise saponin or stevioside scaffolds. The model highlights that their sweetness potency is comparable to known natural sweeteners. The identified compounds provide a rational basis to initiate the design and chemosensory analysis of new low-calorie sweeteners. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. Alkylation of organic aromatic compounds

    Science.gov (United States)

    Smith, Jr., Lawrence A.

    1989-01-01

    Aromatic compounds are alkylated in a catalytic distillation, wherein the catalyst structure also serves as a distillation component by contacting the aromatic compound with a C.sub.2 to C.sub.10 olefin in the catalyst bed under 0.25 to 50 atmospheres of pressure and at temperatures in the range of 80.degree. C. to 500.degree. C., using as the catalyst a mole sieve characterized as acidic or an acidic cation exchange resin. For example, ethyl benzene is produced by feeding ethylene below the catalyst bed while benzene is conveniently added through the reflux in molar excess to that required to react with ethylene, thereby reacting substantially all of the ethylene and recovering benzene as the principal overhead and ethyl benzene in the bottoms.

  16. Bacterial Degradation of Aromatic Compounds

    Directory of Open Access Journals (Sweden)

    Qing X. Li

    2009-01-01

    Full Text Available Aromatic compounds are among the most prevalent and persistent pollutants in the environment. Petroleum-contaminated soil and sediment commonly contain a mixture of polycyclic aromatic hydrocarbons (PAHs and heterocyclic aromatics. Aromatics derived from industrial activities often have functional groups such as alkyls, halogens and nitro groups. Biodegradation is a major mechanism of removal of organic pollutants from a contaminated site. This review focuses on bacterial degradation pathways of selected aromatic compounds. Catabolic pathways of naphthalene, fluorene, phenanthrene, fluoranthene, pyrene, and benzo[a]pyrene are described in detail. Bacterial catabolism of the heterocycles dibenzofuran, carbazole, dibenzothiophene, and dibenzodioxin is discussed. Bacterial catabolism of alkylated PAHs is summarized, followed by a brief discussion of proteomics and metabolomics as powerful tools for elucidation of biodegradation mechanisms.

  17. Process Challenges in Compound Semiconductors.

    Science.gov (United States)

    1988-08-01

    eliminate problems arising from donor-related electron traps (so-called DX centers) in doped AlGaAs with high aluminum content. With a 0.25-micrometer...several problems in common. Fundamental problems associated with the chloride chemistry prevent the growth of aluminum -containing compounds and alloys...It delivers excellent uniformity and good thickness control. Since it is compatible with the trichloride method, high-purity source material is

  18. CEC of phytochemical bioactive compounds.

    Science.gov (United States)

    Yang, Feng-qing; Zhao, Jing; Li, Shao-ping

    2010-01-01

    Although there are many publications related to technological or methodological developments of CEC, few focus on the analysis of natural products, especially phytochemical bioactive compounds. This review summarized the application of CEC in the analysis of phytochemical bioactive components, including flavonoids, nucleosides, steroids, lignans, quinones and coumarins, as well as fingerprint analysis of herbs. The strategies for optimization of CEC conditions and detection were also discussed.

  19. Testing of Experimental Antileishmanial Compounds.

    Science.gov (United States)

    1994-10-19

    Maximum 200 words) Six plant derivatives which were selected for in vivo study because of their in vitro anti leishmanjat activity and low toxicity...of treatment and evaluation of results was extended up to 4-6 weeks to evaluate any possible delayed anti leishmaniat activity by the compounds. None...trypomastigotes in the blood during acute infections of Trypanosoma cruzi in mice. J. Protozool. 21: 512-517. 11. Wilson, H. R., B. W. Dieckmann, and G. E. Childs

  20. Triterpenes as Potentially Cytotoxic Compounds

    Directory of Open Access Journals (Sweden)

    Malwina Chudzik

    2015-01-01

    Full Text Available Triterpenes are compounds of natural origin, which have numerously biological activities: anti-cancer properties, anti-inflammatory, anti-oxidative, anti-viral, anti-bacterial and anti-fungal. These substances can be isolated from plants, animals or fungi. Nowadays, when neoplasms are main cause of death, triterpenes can become an alternative method for treating cancer because of their cytotoxic properties and chemopreventive activities.

  1. Thermal properties of tetrahedral compounds

    International Nuclear Information System (INIS)

    Kagaya, H.M.; Soma, T.

    1987-01-01

    The thermal properties of tetrahedral compounds are studied theoretically from first principle using the lattice dynamical method recently developed. Numerical calculations about the specific heat are performed for AlP, AlAs, AlSb and about the thermal expansion coefficient for AlP, AlAs, AlSb, ZnS, ZnSe, ZnTe, and CdTe. (author)

  2. Polyfluoroalkyl compounds in landfill leachates

    International Nuclear Information System (INIS)

    Busch, Jan; Ahrens, Lutz; Sturm, Renate; Ebinghaus, Ralf

    2010-01-01

    Polyfluoroalkyl compounds (PFCs) are widely used in industry and consumer products. These products could end up finally in landfills where their leachates are a potential source for PFCs into the aqueous environment. In this study, samples of untreated and treated leachate from 22 landfill sites in Germany were analysed for 43 PFCs. ΣPFC concentrations ranged from 31 to 12,819 ng/L in untreated leachate and 4-8060 ng/L in treated leachate. The dominating compounds in untreated leachate were perfluorobutanoic acid (PFBA) (mean contribution 27%) and perfluorobutane sulfonate (PFBS) (24%). The discharge of PFCs into the aqueous environment depended on the cleaning treatment systems. Membrane treatments (reverse osmosis and nanofiltrations) and activated carbon released lower concentrations of PFCs into the environment than cleaning systems using wet air oxidation or only biological treatment. The mass flows of ΣPFCs into the aqueous environment ranged between 0.08 and 956 mg/day. - The first comprehensive survey of polyfluoroalkyl compounds (PFCs) in landfill leachates.

  3. Studying the propensity of compounds to supersaturate

    DEFF Research Database (Denmark)

    Palmelund, Henrik; Madsen, Cecilie Maria; Christensen, Jakob Plum

    2016-01-01

    Supersaturating drug delivery systems can enhance the oral bioavailability of poorly soluble drug compounds. Supersaturation of such compounds has been studied in many different ways; however, a more standardized method is required. The rationale of choosing suitable concentrations of supersatura......Supersaturating drug delivery systems can enhance the oral bioavailability of poorly soluble drug compounds. Supersaturation of such compounds has been studied in many different ways; however, a more standardized method is required. The rationale of choosing suitable concentrations...... of supersaturation to study has previously been very inconsistent. This makes comparisons between studies and compounds difficult, as the propensity of compounds to supersaturate varies greatly. This study presents a standardized method to study the supersaturation of drug compounds. The method allows, both......, for a ranking of compounds according to their supersaturation propensity and the effectiveness of precipitation inhibitors. The time-concentration profile of supersaturation and precipitation was studied in situ for 4 different concentrations for 6 model compounds (albendazole, aprepitant, danazol, felodipine...

  4. Bioactive compounds from northern plants.

    Science.gov (United States)

    Hohtola, Anja

    2010-01-01

    Northern conditions are characterised by long days with much light and low temperatures during the growing season. It has been chimed that herbs and berries grown in the north are stronger tasting compared to those of southern origin. The compounds imparting aroma and color to berries and herbs are secondary metabolites which in plants mostly act as chemical means of defense. Recently, the production of secondary metabolites using plant cells has been the subject of expanding research. Light intensity, photoperiod and temperature have been reported to influence the biosynthesis of many secondary metabolites. Native wild aromatic and medicinal plant species of different families are being studied to meet the needs of raw material for the expanding industry of e.g., health-promoting food products known as nutraceutics. There are already a large number of known secondary compounds produced by plants, but the recent advances in modern extraction and analysis should enable many more as yet unknown compounds to be found, characterised and utilised. Rose root (Rhodiola rosea) is a perennial herbaceous plant which inhabits mountain regions throughout Europe, Asia and east coastal regions of North America. The extract made from the rhizomes acts as a stimulant like the Ginseng root. Roseroot has been categorized as an adaptogen and is reported to have many pharmacological properties. The biologically active components of the extract are salitroside tyrosol and cinnamic acid glycosides (rosavin, rosarin, rosin). Round-leaved sundew (Drosera rotundifolia L.) has circumboreal distribution. It inhabits nutrient-poor, moist and sunny areas such as peat bogs and wetlands. Sundew leaves are collected from the wild-type for various medicinal preparations and can be utilized in treating e.g., as an important "cough-medicine" for different respiratory diseases. The antimicrobial activity of extracts of aerial parts against various bacteria has been investigated. Drosera produces

  5. A novel sensor made of Antimony Doped Tin Oxide-silica composite sol on a glassy carbon electrode modified by single-walled carbon nanotubes for detection of norepinephrine.

    Science.gov (United States)

    Wang, Zhao; Wang, Kai; Zhao, Lu; Chai, Shigan; Zhang, Jinzhi; Zhang, Xiuhua; Zou, Qichao

    2017-11-01

    In this study, we designed a novel molecularly imprinted polymer (MIP), Antimony Doped Tin Oxide (ATO)-silica composite sol, which was made using a sol-gel method. Then a sensitive and selective imprinted electrochemical sensor was constructed with the ATO-silica composite sol on a glassy carbon electrode modified by single-walled carbon nanotubes (SWNTs). The introduction of SWNTs increased the sensitivity of the MIP sensor. The surface morphology of the MIP and MIP/SWNTs were characterized by scanning electron microscopy (SEM), and the optimal conditions for detection were determined. The oxidative peak current increased linearly with the concentration of norepinephrine in the range of 9.99×10 -8 M to 1.50×10 -5 M, as detected by cyclic voltammetry (CV), the detection limit was 3.33×10 -8 M (S/N=3). In addition, the proposed electrochemical sensors were successfully applied to detect the norepinephrine concentration in human blood serum samples. The recoveries of the sensors varied from 99.67% to 104.17%, indicating that the sensor has potential for the determination of norepinephrine in clinical tests. Moreover, the imprinted electrochemical sensor was used to selectively detect norepinephrine. The analytical application was conducted successfully and yielded accurate and precise results. Copyright © 2017. Published by Elsevier B.V.

  6. Observation of stimulated Raman scattering in polar tetragonal crystals of barium antimony tartrate trihydrate, Ba[Sb{sub 2}((+)C{sub 4}H{sub 2}O{sub 6}){sub 2}].3H{sub 2}O

    Energy Technology Data Exchange (ETDEWEB)

    Kaminskii, Alexander A. [Institute of Crystallography, Russian Academy of Sciences, Moscow (Russian Federation); Rhee, Hanjo; Eichler, Hans J.; Lux, Oliver [Institute of Optics and Atomic Physics, Technical University of Berlin (Germany); Nemec, Ivan [Department of Inorganic Chemistry, Faculty of Science, Charles University, Prague (Czech Republic); Yoneda, Hitoki; Shirakawa, Akira [Institute for Laser Science, University of Electro-Communications, Tokyo (Japan); Becker, Petra; Bohaty, Ladislav [Section Crystallography, Institute of Geology and Mineralogy, University of Cologne (Germany)

    2017-04-15

    The non-centrosymmetric polar tetragonal (P4{sub 1}) barium antimony tartrate trihydrate, Ba[Sb{sub 2}((+)C{sub 4}H{sub 2}O{sub 6}){sub 2}].3H{sub 2}O, was found to be an attractive novel semi-organic crystal manifesting numerous χ{sup (2)}- and χ{sup (3)}-nonlinear optical interactions. In particular, with picosecond single- and dual-wavelength pumping SHG and THG via cascaded parametric four-wave processes were observed. High-order Stokes and anti-Stokes lasing related to two SRS-promoting vibration modes of the crystal, with ω{sub SRS1} ∼ 575 cm{sup -1} and ω{sub SRS2} ∼ 2940 cm{sup -1}, takes place. Basing on a spontaneous Raman investigation an assignment of the two SRS-active vibration modes is discussed. (copyright 2017 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  7. Optical Characterization of Nano- and Microcrystals of EuPO4 Created by One-Step Synthesis of Antimony-Germanate-Silicate Glass Modified by P2O5

    Science.gov (United States)

    Zmojda, Jacek; Kochanowicz, Marcin; Baranowska, Agata; Pisarski, Wojciech A.; Pisarska, Joanna; Jadach, Renata; Sitarz, Maciej; Dorosz, Dominik

    2017-01-01

    Technology of active glass-ceramics (GC) is an important part of luminescent materials engineering. The classic method to obtain GC is based on annealing of parent glass in proper temperature and different time periods. Generally, only the bulk materials are investigated as a starting host for further applications. However, the effect of an additional heat-treatment process on emission and structural properties during GC processing is omitted. Here, we focus on the possibility of obtaining transparent glass-ceramic doped with europium ions directly with a melt-quenching method. The influence of phosphate concentration (up to 10 mol %) on the inversion symmetry of local environment of Eu3+ ions in antimony-germanate-silicate (SGS) glass has been investigated. The Stark splitting of luminescence spectra and the local asymmetry ratio estimated by relation of (5D0→7F2)/(5D0→7F1) transitions in fabricated glass confirms higher local symmetry around Eu3+ ions. Based on XRD and SEM/EDX measurements, the EuPO4 nano- and microcrystals with monoclinic geometry were determined. Therefore, in our experiment, we confirmed possibility of one-step approach to fabricate crystalline structures (glass-ceramic) in Eu–doped SGS glass without additional annealing process. PMID:28891945

  8. Nitrogen Compounds in Radiation Chemistry

    International Nuclear Information System (INIS)

    Sims, H.E.; Dey, G.R.; Vaudey, C.E.; Peaucelle, C.; Boucher, J.L.; Toulhoat, N.; Bererd, N.; Koppenol, W.H.; Janata, E.; Dauvois, V.; Durand, D.; Legand, S.; Roujou, J.L.; Doizi, D.; Dannoux, A.; Lamouroux, C.

    2009-01-01

    Water radiolysis in presence of N 2 is probably the topic the most controversy in the field of water radiolysis. It still exists a strong discrepancy between the different reports of ammonia formation by water radiolysis in presence of N 2 and moreover in absence of oxygen there is no agreement on the formation or not of nitrogen oxide like NO 2 - and NO 3 -. These discrepancies come from multiple sources: - the complexity of the reaction mechanisms where nitrogen is involved - the experimental difficulties - and, the irradiation conditions. The aim of the workshop is to capitalize the knowledge needed to go further in simulations and understanding the problems caused (or not) by the presence of nitrogen / water in the environment of radioactive materials. Implications are evident in terms of corrosion, understanding of biological systems and atmospheric chemistry under radiation. Topics covered include experimental and theoretical approaches, application and fundamental researches: - Nitrate and Ammonia in radiation chemistry in nuclear cycle; - NOx in biological systems and atmospheric chemistry; - Formation of Nitrogen compounds in Nuclear installations; - Nitrogen in future power plant projects (Gen4, ITER...) and large particle accelerators. This document gathers the transparencies available for 7 of the presentations given at this workshop. These are: - H.E SIMS: 'Radiation Chemistry of Nitrogen Compounds in Nuclear Power Plant'; - G.R. DEY: 'Nitrogen Compounds Formation in the Radiolysis of Aqueous Solutions'; - C.E. VAUDEY et al.: 'Radiolytic corrosion of nuclear graphite studied with the dedicated gas irradiation cell of IPNL'; - J.L. BOUCHER: 'Roles and biosynthesis of NO in eukaryotes and prokaryotes'; - W.H. KOPPENOL: 'Chemistry of NOx'; - E. JANATA: 'Yield of OH in N 2 O saturated aqueous solution'; - V. DAUVOIS: 'Analytical strategy for the study of radiolysis gases'

  9. Benzimidazoles: A biologically active compounds

    Directory of Open Access Journals (Sweden)

    Salahuddin

    2017-02-01

    Full Text Available Synthesis of commercially available benzimidazole involves condensation of o-phenylenediamine with formic acid. The most prominent benzimidazole compound in nature is N-riosyldimethylbenzimidazole, which serves as a axial ligand for cobalt in vitamin B12. The benzimidazole and its derivatives play a very important role as a therapeutic agent e.g. antiulcer and anthelmintic drugs. Apart from this the benzimidazole derivatives exhibit pharmacological activities such as antimicrobial, antiviral, anticancer, anti-inflammatory, analgesic, etc. The substituted benzimidazoles are summarized in this review to know about the chemistry as well as pharmacological activities.

  10. Selenium-containing indolyl compounds

    DEFF Research Database (Denmark)

    Casaril, Angela M; Ignasiak, Marta T; Chuang, Christine Y

    2017-01-01

    materials, including extracellular matrix (ECM) proteins, within the artery wall. Here we investigated the potential of selenium-containing indoles to afford protection against these oxidants, by determining rate constants (k) for their reaction, and quantifying the extent of damage on isolated ECM proteins......Tyr on HCAEC-ECM were also reduced. These data demonstrate that the novel selenium-containing compounds show high reactivity with oxidants and may modulate oxidative and nitrosative damage at sites of inflammation, contributing to a reduction in tissue dysfunction and atherogenesis....

  11. Raman spectra of lithium compounds

    Science.gov (United States)

    Gorelik, V. S.; Bi, Dongxue; Voinov, Y. P.; Vodchits, A. I.; Gorshunov, B. P.; Yurasov, N. I.; Yurasova, I. I.

    2017-11-01

    The paper is devoted to the results of investigating the spontaneous Raman scattering spectra in the lithium compounds crystals in a wide spectral range by the fibre-optic spectroscopy method. We also present the stimulated Raman scattering spectra in the lithium hydroxide and lithium deuteride crystals obtained with the use of powerful laser source. The symmetry properties of the lithium hydroxide, lithium hydroxide monohydrate and lithium deuteride crystals optical modes were analyzed by means of the irreducible representations of the point symmetry groups. We have established the selection rules in the Raman and infrared absorption spectra of LiOH, LiOH·H2O and LiD crystals.

  12. Lipid encapsulated phenolic compounds by fluidization

    Science.gov (United States)

    Phenolic compounds exhibit antioxidant and antimicrobial activities with applications as functional food and feed additives. Ferulic acid, a phenolic compound present in grain crops and lignocellulose biomass, was encapsulated with saturated triglycerides using a laboratory fluidizer. Stability of t...

  13. Characterisation of selected volatile organic compounds in ...

    African Journals Online (AJOL)

    GCMS), was used to identify volatile compounds at three different temperatures. Fifty volatile compounds, inclusive of 14 acids, 14 alcohols, and 22 esters were identified and quantified in the two brands of indigenous banana beer samples. Only 12 ...

  14. Aroma compounds in fresh cut pomegranate arils.

    Science.gov (United States)

    Little published information exists regarding flavor and aroma compounds in pomegranate (Punica granatum). Although arils have fruity and sweet characteristics, we found no publications describing actual compounds responsible for their typical flavor. Since most commercial usage of pomegranates in...

  15. Two new acetylenic compounds from Asparagus officinalis.

    Science.gov (United States)

    Li, Xue-Mei; Cai, Jin-Long; Wang, Wen-Xiang; Ai, Hong-Lian; Mao, Zi-Chao

    2016-01-01

    Two new acetylenic compounds, asparoffins A (1) and B (2), together with two known compounds, nyasol (3) and 3″-methoxynyasol (4), were isolated from stems of Asparagus officinalis. The structures of two new compounds were elucidated on the basis of detailed spectroscopic analyses (UV, IR, MS, 1D, and 2D NMR). All compounds were evaluated for their cytotoxicities against three human cancer cell lines.

  16. Compound Data Mining for Drug Discovery.

    Science.gov (United States)

    Bajorath, Jürgen

    2017-01-01

    In recent years, there has been unprecedented growth in compound activity data in the public domain. These compound data provide an indispensable resource for drug discovery in academic environments as well as in the pharmaceutical industry. To handle large volumes of heterogeneous and complex compound data and extract discovery-relevant knowledge from these data, advanced computational mining approaches are required. Herein, major public compound data repositories are introduced, data confidence criteria reviewed, and selected data mining approaches discussed.

  17. Separation of compounds differing in isotopic composition

    International Nuclear Information System (INIS)

    Sievers, R.E.; Brooks, J.J.

    1976-01-01

    Compounds differing in isotopic composition are separated by introducing a mixture of the compounds into a chromatographic column containing a lanthanide chelate as a stationary phase and eluting from the column a fraction which is at least enriched with one of the compounds of the mixture. 17 claims, no drawings

  18. The Modification of Compounds by Attributive Adjectives

    Science.gov (United States)

    Berg, Thomas

    2011-01-01

    This paper examines the modification of nominal compounds by attributive adjectives in English. It draws on a distinction between compound-external (i.e. syntactic) and compound-internal (i.e. morphological) modification. An analysis is presented of more than 1000 pertinent cases, which are roughly equally divided into two-, three- and four-noun…

  19. Separation of compounds differing in isotopic composition

    International Nuclear Information System (INIS)

    Sievers, R.E.; Brooks, J.J.

    1975-01-01

    Compounds differing in isotopic composition are separated by introducing a mixture of the compounds into a chromatographic column containing a lanthanide chelate as a stationary phase and eluting from the column a fraction that is at least enriched with one of the compounds of the mixture. (U.S.)

  20. Superconductivity in graphite intercalation compounds

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Robert P. [Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE (United Kingdom); Weller, Thomas E.; Howard, Christopher A. [Department of Physics & Astronomy, University College of London, Gower Street, London WCIE 6BT (United Kingdom); Dean, Mark P.M. [Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, NY 11973 (United States); Rahnejat, Kaveh C. [Department of Physics & Astronomy, University College of London, Gower Street, London WCIE 6BT (United Kingdom); Saxena, Siddharth S. [Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE (United Kingdom); Ellerby, Mark, E-mail: mark.ellerby@ucl.ac.uk [Department of Physics & Astronomy, University College of London, Gower Street, London WCIE 6BT (United Kingdom)

    2015-07-15

    Highlights: • Historical background of graphite intercalates. • Superconductivity in graphite intercalates and its place in the field of superconductivity. • Recent developments. • Relevant modeling of superconductivity in graphite intercalates. • Interpretations that pertain and questions that remain. - Abstract: The field of superconductivity in the class of materials known as graphite intercalation compounds has a history dating back to the 1960s (Dresselhaus and Dresselhaus, 1981; Enoki et al., 2003). This paper recontextualizes the field in light of the discovery of superconductivity in CaC{sub 6} and YbC{sub 6} in 2005. In what follows, we outline the crystal structure and electronic structure of these and related compounds. We go on to experiments addressing the superconducting energy gap, lattice dynamics, pressure dependence, and how these relate to theoretical studies. The bulk of the evidence strongly supports a BCS superconducting state. However, important questions remain regarding which electronic states and phonon modes are most important for superconductivity, and whether current theoretical techniques can fully describe the dependence of the superconducting transition temperature on pressure and chemical composition.