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Sample records for antimony selenides

  1. Polycrystalline thin films of antimony selenide via chemical bath deposition and post deposition treatments

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Lazcano, Y. [Department of Solar Energy Materials, Centro de Investigacion en Energia, Universidad Nacional Autonoma de Mexico, Temixco, Morelos-62580 (Mexico); Pena, Yolanda [Department of Solar Energy Materials, Centro de Investigacion en Energia, Universidad Nacional Autonoma de Mexico, Temixco, Morelos-62580 (Mexico); Nair, M.T.S. [Department of Solar Energy Materials, Centro de Investigacion en Energia, Universidad Nacional Autonoma de Mexico, Temixco, Morelos-62580 (Mexico)]. E-mail: mtsn@cie.unam.mx; Nair, P.K. [Department of Solar Energy Materials, Centro de Investigacion en Energia, Universidad Nacional Autonoma de Mexico, Temixco, Morelos-62580 (Mexico)

    2005-12-22

    We report a method for obtaining thin films of polycrystalline antimony selenide via chemical bath deposition followed by heating the thin films at 573 K in selenium vapor. The thin films deposited from chemical baths containing one or more soluble complexes of antimony, and selenosulfate initially did not show X-ray diffraction (XRD) patterns corresponding to crystalline antimony selenide. Composition of the films, studied by energy dispersive X-ray analyses indicated selenium deficiency. Heating these films in presence of selenium vapor at 573 K under nitrogen (2000 mTorr) resulted in an enrichment of Se in the films. XRD peaks of such films matched Sb{sub 2}Se{sub 3}. Evaluation of band gap from optical spectra of such films shows absorption due to indirect transition occurring in the range of 1-1.2 eV. The films are photosensitive, with dark conductivity of about 2 x 10{sup -8} ({omega} cm){sup -1} and photoconductivity, about 10{sup -6} ({omega} cm){sup -1} under tungsten halogen lamp illumination with intensity of 700 W m{sup -2}. An estimate for the mobility life time product for the film is 4 x 10{sup -9} cm{sup 2} V{sup -1}.

  2. DFT Study on the Carrier Concentration and Temperature-Dependent Thermoelectric Properties of Antimony Selenide

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    Aditya Jayaraman

    2016-01-01

    Full Text Available We present the thermoelectric properties of Antimony Selenide (Sb2Se3 obtained using first principles calculations. We investigated the electronic band structure using the FP-LAPW method within the sphere of the density functional theory. Thermoelectric properties were calculated using BoltzTrap code using the constant relaxation time (τ approximation at three different temperatures 300 K, 600 K, and 800 K. Seebeck coefficient (S was found to decrease with increasing temperature, electrical conductivity (σ/τ was almost constant in the entire temperature range, and electronic thermal conductivity (κ/τ increased with increasing temperature. With increase in temperature S decreased from 1870 μV/K (at 300 K to 719 μV/K (at 800 K, electronic thermal conductivity increased from 1.56 × 1015 W/m K s (at 300 K to 3.92 × 1015 W/m K s (at 800 K, and electrical conductivity decreased from 22 × 1019/Ω m s (at 300 K to 20 × 1019/Ω m s (at 800 K. The thermoelectric properties were also calculated for different hole concentrations and the optimum concentration for a good thermoelectric performance over a large range of temperatures (from 300 K to 1000 K was found for hole concentration around 1019 cm−3.

  3. Antimony selenide thin-film solar cells

    Science.gov (United States)

    Zeng, Kai; Xue, Ding-Jiang; Tang, Jiang

    2016-06-01

    Due to their promising applications in low-cost, flexible and high-efficiency photovoltaics, there has been a booming exploration of thin-film solar cells using new absorber materials such as Sb2Se3, SnS, FeS2, CuSbS2 and CuSbSe2. Among them, Sb2Se3-based solar cells are a viable prospect because of their suitable band gap, high absorption coefficient, excellent electronic properties, non-toxicity, low cost, earth-abundant constituents, and intrinsically benign grain boundaries, if suitably oriented. This review surveys the recent development of Sb2Se3-based solar cells with special emphasis on the material and optoelectronic properties of Sb2Se3, the solution-based and vacuum-based fabrication process and the recent progress of Sb2Se3-sensitized and Sb2Se3 thin-film solar cells. A brief overview further addresses some of the future challenges to achieve low-cost, environmentally-friendly and high-efficiency Sb2Se3 solar cells.

  4. Antimony Toxicity

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    Shyam Sundar

    2010-12-01

    Full Text Available Antimony toxicity occurs either due to occupational exposure or during therapy. Occupational exposure may cause respiratory irritation, pneumoconiosis, antimony spots on the skin and gastrointestinal symptoms. In addition antimony trioxide is possibly carcinogenic to humans. Improvements in working conditions have remarkably decreased the incidence of antimony toxicity in the workplace. As a therapeutic, antimony has been mostly used for the treatment of leishmaniasis and schistosomiasis. The major toxic side-effects of antimonials as a result of therapy are cardiotoxicity (~9% of patients and pancreatitis, which is seen commonly in HIV and visceral leishmaniasis co-infections. Quality control of each batch of drugs produced and regular monitoring for toxicity is required when antimonials are used therapeutically.

  5. Formation of copper-indium-selenide and/or copper-indium-gallium-selenide films from indium selenide and copper selenide precursors

    Science.gov (United States)

    Curtis, Calvin J.; Miedaner, Alexander; Van Hest, Maikel; Ginley, David S.; Nekuda, Jennifer A.

    2011-11-15

    Liquid-based indium selenide and copper selenide precursors, including copper-organoselenides, particulate copper selenide suspensions, copper selenide ethylene diamine in liquid solvent, nanoparticulate indium selenide suspensions, and indium selenide ethylene diamine coordination compounds in solvent, are used to form crystalline copper-indium-selenide, and/or copper indium gallium selenide films (66) on substrates (52).

  6. Pentavalent Antimonials: New Perspectives for Old Drugs

    OpenAIRE

    Ribeiro, Raul R.; Cynthia Demicheli; Frédéric Frézard

    2009-01-01

    Pentavalent antimonials, including meglumine antimoniate and sodium stibogluconate, have been used for more than half a century in the therapy of the parasitic disease leishmaniasis. Even though antimonials are still the first-line drugs, they exhibit several limitations, including severe side effects, the need for daily parenteral administration and drug resistance. The molecular structure of antimonials, their metabolism and mechanism of action are still being investigated. Some recent stud...

  7. Pentavalent Antimonials: New Perspectives for Old Drugs

    Directory of Open Access Journals (Sweden)

    Raul R. Ribeiro

    2009-06-01

    Full Text Available Pentavalent antimonials, including meglumine antimoniate and sodium stibogluconate, have been used for more than half a century in the therapy of the parasitic disease leishmaniasis. Even though antimonials are still the first-line drugs, they exhibit several limitations, including severe side effects, the need for daily parenteral administration and drug resistance. The molecular structure of antimonials, their metabolism and mechanism of action are still being investigated. Some recent studies suggest that pentavalent antimony acts as a prodrug that is converted to active and more toxic trivalent antimony. Other works support the direct involvement of pentavalent antimony. Recent data suggest that the biomolecules, thiols and ribonucleosides, may mediate the actions of these drugs. This review will summarize the progress to date on the chemistry and biochemistry of pentavalent antimony. It will also present the most recent works being done to improve antimonial chemotherapy. These works include the development of simple synthetic methods for pentavalent antimonials, liposome-based formulations for targeting the Leishmania parasites responsible for visceral leishmaniasis and cyclodextrin-based formulations to promote the oral delivery of antimony.

  8. Selenide isotope generator for the Galileo mission

    International Nuclear Information System (INIS)

    A significantly improved thermoelectric generator has been developed to provide electric power for NASA's Galileo Mission in 1982. Nominal power requirements for Galileo will be about 450 watts at BOL (Beginning of Life), and this will be furnished by two Selenide Isotope Generators (SIG) each powered by a Multi Hundred Watt (MHW) radioisotopic heat source. A Ground Demonstration System (GDS) of a nominal 100 w(e) features a 3M - produced selenide ring module around a shortened MHW-dimensioned electrical heat source, newly developed axially-grooved heat pipes on a disc-shaped radiator, and other innovations which will allow a full-sized generator's weight to be held at about 90 lbs

  9. Improved thermoelectric performance of Nb-doped lead selenide

    Energy Technology Data Exchange (ETDEWEB)

    Han, Yemao; Chen, Zhen; Xin, Caini [State Key Laboratory of Technologies in Space Cryogenic Propellants, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Pei, Yanzhong [School of Materials Science and Engineering, Tongji University, 4800 Caoan Road, Shanghai 201804 (China); Zhou, Min, E-mail: mzhou@mail.ipc.ac.cn [State Key Laboratory of Technologies in Space Cryogenic Propellants, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Huang, Rongjin [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Li, Laifeng, E-mail: laifengli@mail.ipc.ac.cn [State Key Laboratory of Technologies in Space Cryogenic Propellants, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China)

    2014-07-05

    Highlights: • Thermoelectric performance of Nb-doped lead selenide was investigated. • Higher Seebeck coefficient was obtained in Nb-doped lead selenide. • The grain sizes are about 100-300 nm according to SEM. • There is little lattice thermal conductivity decrease. - Abstract: In present work, niobium is used as donor impurity in lead selenide to increase carrier concentration. Thermoelectric transport properties of n-type Pb{sub 1.04−x}Nb{sub x}Se are investigated from room temperature to 673 K. Higher Seebeck coefficient is reached by Nb-doping in lead selenide compared to other dopants. The Seebeck coefficient enhancement comes from band modification by Nb-doping, which results in the density of states effective mass increase. With the Seebeck coefficient enhancement, the dimensionless figure of merit ZT reaches ∼1.1 at 673 K.

  10. Copper selenide nanocrystals for photothermal therapy.

    Science.gov (United States)

    Hessel, Colin M; Pattani, Varun P; Rasch, Michael; Panthani, Matthew G; Koo, Bonil; Tunnell, James W; Korgel, Brian A

    2011-06-01

    Ligand-stabilized copper selenide (Cu(2-x)Se) nanocrystals, approximately 16 nm in diameter, were synthesized by a colloidal hot injection method and coated with amphiphilic polymer. The nanocrystals readily disperse in water and exhibit strong near-infrared (NIR) optical absorption with a high molar extinction coefficient of 7.7 × 10(7) cm(-1) M(-1) at 980 nm. When excited with 800 nm light, the Cu(2-x)Se nanocrystals produce significant photothermal heating with a photothermal transduction efficiency of 22%, comparable to nanorods and nanoshells of gold (Au). In vitro photothermal heating of Cu(2-x)Se nanocrystals in the presence of human colorectal cancer cell (HCT-116) led to cell destruction after 5 min of laser irradiation at 33 W/cm(2), demonstrating the viabilitiy of Cu(2-x)Se nanocrystals for photothermal therapy applications. PMID:21553924

  11. FIRST REPORT ON OTOTOXICITY OF MEGLUMINE ANTIMONIATE

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    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.

  12. Preparation and properties of antimony thin film anode materials

    Institute of Scientific and Technical Information of China (English)

    SU Shufa; CAO Gaoshao; ZHAO Xinbing

    2004-01-01

    Metallic antimony thin films were deposited by magnetron sputtering and electrodeposition. Electrochemical properties of the thin film as anode materials for lithium-ion batteries were investigated and compared with those of antimony powder. It was found that both magnetron sputtering and electrodeposition are easily controllable processes to deposit antimony films with fiat charge/discharge potential plateaus. The electrochemical performances of antimony thin films, especially those prepared with magnetron sputtering, are better than those of antimony powder. The reversible capacities of the magnetron sputtered antimony thin film are above 400 mA h g-1 in the first 15 cycles.

  13. 21 CFR 862.3110 - Antimony test system.

    Science.gov (United States)

    2010-04-01

    ... antimony, a heavy metal, in urine, blood, vomitus, and stomach contents. Measurements obtained by this device are used in the diagnosis and treatment of antimony poisoning. (b) Classification. Class I....

  14. Superconductivity in alkali metal intercalated iron selenides

    Science.gov (United States)

    Krzton-Maziopa, A.; Svitlyk, V.; Pomjakushina, E.; Puzniak, R.; Conder, K.

    2016-07-01

    Alkali metal intercalated iron selenide superconductors A x Fe2‑y Se2 (where A  =  K, Rb, Cs, Tl/K, and Tl/Rb) are characterized by several unique properties, which were not revealed in other superconducting materials. The compounds crystallize in overall simple layered structure with FeSe layers intercalated with alkali metal. The structure turned out to be pretty complex as the existing Fe-vacancies order below ~550 K, which further leads to an antiferromagnetic ordering with Néel temperature fairly above room temperature. At even lower temperatures a phase separation is observed. While one of these phases stays magnetic down to the lowest temperatures the second is becoming superconducting below ~30 K. All these effects give rise to complex relationships between the structure, magnetism and superconductivity. In particular the iron vacancy ordering, linked with a long-range magnetic order and a mesoscopic phase separation, is assumed to be an intrinsic property of the system. Since the discovery of superconductivity in those compounds in 2010 they were investigated very extensively. Results of the studies conducted using a variety of experimental techniques and performed during the last five years were published in hundreds of reports. The present paper reviews scientific work concerning methods of synthesis and crystal growth, structural and superconducting properties as well as pressure investigations.

  15. Amphoteric properties of gold in zinc selenide

    International Nuclear Information System (INIS)

    Hall effect, electric conductivity, and charge carriers mobility in n-ZnSe single crystals doped with gold during the process of a long-term high-temperature annealing in Zn+Au melt with various Au contents were investigated in the temperature range from 77 to 300 K. It has been established that, at low gold concentration, Au atoms form mainly donor-type interstitial Aui defects. The increase of Au concentration in Zn+Au melt leads to the formation of both simple AuZn defects and associative acceptors (AuZn-Aui) (AuZn-DZn), and (AuZn-VSe). These defects determine electrical properties of the crystals and they are responsible for the complex structure of excitonic and impurity radiation spectra. The influence of dopant concentration on both electrical and luminescent properties of n-ZnSe:Zn:Au crystals is investigated. The observed variations of electrical and luminescent properties are due to amphoteric properties of gold impurity in zinc selenide

  16. Perspectives of antimony compounds in oncology

    Institute of Scientific and Technical Information of China (English)

    Pankaj SHARMA; Diego PEREZ; Armando CABRERA; Nee ROSAS; Jose Luis ARIAS

    2008-01-01

    Antimony, a natural element that has been used as a drug for over more than 100 years, has remarkable therapeutic efficacy in patients with acute promyelocytic leukemia. This review focuses on recent advances in developing antimony anti- cancer agents with an emphasis on antimony coordination complexes, Sb (Ⅲ) and Sb (V). These complexes, which include many organometallic complexes, may provide a broader spectrum of antitumoral activity. They were compared with classical platinum anticancer drugs. The review covers the literature data pub- lished up to 2007. A number of antimonials with different antitumoral activities are known and have diverse applications, even though little research has been done on their possibilities. It might be feasible to develop more specific and effective inhibitors for phosphatase-targeted, anticancer therapeutics through the screen- ing of sodium stibogluconate (SSG) and potassium antimonyltartrate-related compounds, which are comprised of antimony conjugated to different organic moieties. For example, SSG appears to be a better inhibitor than suramin which is a compound known for its antineoplastic activity against several types of cancers.

  17. Infrared surface polaritons on antimony.

    Science.gov (United States)

    Cleary, Justin W; Medhi, Gautam; Shahzad, Monas; Rezadad, Imen; Maukonen, Doug; Peale, Robert E; Boreman, Glenn D; Wentzell, Sandy; Buchwald, Walter R

    2012-01-30

    The semimetal antimony, with a plasma frequency ~80 times less than that of gold, is potentially useful as a host for infrared surface polaritons (SPs). Relevant IR SP properties, including the frequency-dependent propagation length and penetration depths for fields into the media on either side of the interface, were determined from optical constants measured on optically-thick thermally-evaporated Sb films over the wavelength range 1 to 40 μm. Plasma and carrier relaxation frequencies were determined from Drude-model fits to these data. The real part of the permittivity is negative for wavelengths beyond 11 μm. Distinct resonant decreases in specular reflected intensity were observed for Sb lamellar gratings in the wavelength range of 6 to 11 μm, where the real part of the permittivity is positive. Both resonance angles and the angular reflectance spectral line shapes are in agreement with theory for excitation of bound surface electromagnetic waves (SPs). Finite element method (FEM) electrodynamic simulations indicate the existence of SP modes under conditions matching the experiments. FEM results also show that such waves depend on having a significant imaginary part of the permittivity, as has been noted earlier for the case of surface exciton polaritons.

  18. Synthesis and application of antimony pent(isooctyl thioglycollate)

    Institute of Scientific and Technical Information of China (English)

    LIU You-nian; LI Hong-bing; SHU Wan-gen; CHEN Qi-yuan

    2005-01-01

    A new type of thermal stabilizer, antimony pent(isooctyl thioglycollate)(Sb(SCH2COOC8H17)5), was synthesized by using antimony trioxide, isooctanol and thioglycolic acid in 2 steps. Firstly, antimony trioxide was oxidized into colloidal antimony peroxide. Then antimony peroxide and isooctyl thioglycollate reacted stoichiometrically for 2 h with the yield of 87%. This compound was used as thermal stabilizer for polyvinyl chloride(PVC). The results show that the thermal stability time is 52 min at 200 ℃ by heat-ageing oven test when adding 2.5% thermal stabilizer to PVC resin. Compared with antimony tris(isooctyl thiolycollate), the initial thermal stability of antimony pent(isooctyl thioglycollate) is better than that of antimony tris(isooctyl thioglycollate), while the long-term thermal stability time is shorter than that of antimony tris(isooctyl thioglycollate). Meanwhile, the synergism of antimony pent(isooctyl thioglycollate) with calcium stearate was studied, indicating that when the mass ratio of antimony pent(isooctyl thioglycollate) to calcium stearate is 2:1, the thermal stability time of PVC is 58 min.

  19. Epithermal Gold-Silver Deposits in Western Java, Indonesia: Gold-Silver Selenide-Telluride Mineralization

    Directory of Open Access Journals (Sweden)

    Euis Tintin Yuningsih

    2014-09-01

    Full Text Available DOI: 10.17014/ijog.v1i2.180The gold-silver ores of western Java reflect a major metallogenic event during the Miocene-Pliocene and Pliocene ages. Mineralogically, the deposits can be divided into two types i.e. Se- and Te-type deposits with some different characteristic features. The objective of the present research is to summarize the mineralogical and geochemical characteristics of Se- and Te-type epithermal mineralization in western Java. Ore and alteration mineral assemblage, fluid inclusions, and radiogenic isotope studies were undertaken in some deposits in western Java combined with literature studies from previous authors. Ore mineralogy of some deposits from western Java such as Pongkor, Cibaliung, Cikidang, Cisungsang, Cirotan, Arinem, and Cineam shows slightly different characteristics as those are divided into Se- and Te-types deposits. The ore mineralogy of the westernmost of west Java region such as Pongkor, Cibaliung, Cikidang, Cisungsang, and Cirotan is characterized by the dominance of silver-arsenic-antimony sulfosalt with silver selenides and rarely tellurides over the argentite, while to the eastern part of West Java such as Arinem and Cineam deposits are dominated by silver-gold tellurides. The average formation temperatures measured from fluid inclusions of quartz associated with ore are in the range of 170 – 220°C with average salinity of less than 1 wt% NaClequiv for Se-type and 190 – 270°C with average salinity of ~2 wt% NaClequiv for Te-type.

  20. Vacuum Evaporation Technology for Treating Antimony-Rich Anode Slime

    Science.gov (United States)

    Qiu, Keqiang; Lin, Deqiang; Yang, Xuelin

    2012-11-01

    A vacuum evaporation technology for treating antimony-rich anode slime was developed in this work. Experiments were carried out at temperatures from 873 K to 1073 K and residual gas pressures from 50 Pa to 600 Pa. During vacuum evaporation, silver from the antimony-rich anode slime was left behind in the distilland in a silver alloy containing antimony and lead, and antimony trioxide was evaporated. The experimental results showed that 92% by weight of antimony can be removed, and the silver content in the alloy was up to 12.84%. The antimony trioxide content in the distillate was more than 99.7%, and the distillate can be used directly as zero-grade antimony trioxide (China standard).

  1. 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.”

  2. Arsenic and antimony transporters in eukaryotes.

    Science.gov (United States)

    Maciaszczyk-Dziubinska, Ewa; Wawrzycka, Donata; Wysocki, Robert

    2012-01-01

    Arsenic and antimony are toxic metalloids, naturally present in the environment and all organisms have developed pathways for their detoxification. The most effective metalloid tolerance systems in eukaryotes include downregulation of metalloid uptake, efflux out of the cell, and complexation with phytochelatin or glutathione followed by sequestration into the vacuole. Understanding of arsenic and antimony transport system is of high importance due to the increasing usage of arsenic-based drugs in the treatment of certain types of cancer and diseases caused by protozoan parasites as well as for the development of bio- and phytoremediation strategies for metalloid polluted areas. However, in contrast to prokaryotes, the knowledge about specific transporters of arsenic and antimony and the mechanisms of metalloid transport in eukaryotes has been very limited for a long time. Here, we review the recent advances in understanding of arsenic and antimony transport pathways in eukaryotes, including a dual role of aquaglyceroporins in uptake and efflux of metalloids, elucidation of arsenic transport mechanism by the yeast Acr3 transporter and its role in arsenic hyperaccumulation in ferns, identification of vacuolar transporters of arsenic-phytochelatin complexes in plants and forms of arsenic substrates recognized by mammalian ABC transporters.

  3. Spin dynamics of complex oxides, bismuth-antimony alloys, and bismuth chalcogenides

    Science.gov (United States)

    Sahin, Cuneyt

    V, suggesting the potential for doping or voltage tuned spin Hall current. We have also calculated intrinsic spin Hall conductivities of bismuth selenide and bismuth telluride topological insulators from an effective tight-binding Hamiltonian including two nearest-neighbor interactions. We showed that both materials exhibit giant spin Hall conductivities calculated from the Kubo formula in linear response theory and the clean static limit. We conclude that bismuth-antimony alloys and bismuth chalcogenides are primary candidates for efficiently generating spin currents through the spin Hall effect.

  4. 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)

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

    OpenAIRE

    Samanta Etel Treiger Borborema; Heitor Franco de Andrade Junior; João Alberto Osso Junior; Nanci do Nascimento

    2005-01-01

    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...

  6. Mechanochemical synthesis of nanocrystalline lead selenide. Industrial approach

    Energy Technology Data Exchange (ETDEWEB)

    Achimovicova, Marcela; Balaz, Peter [Slovak Academy of Sciences, Kosice (Slovakia). Inst. of Geotechnics; Durisin, Juraj [Slovak Academy of Sciences, Kosice (Slovakia). Inst. of Materials Research; Daneu, Nina [Josef Stefan Institute, Ljubljana (Slovenia). Dept. for Nanostructured Materials; Kovac, Juraj; Satka, Alexander [Slovak Univ. of Technology and International Laser Centre, Bratislava (Slovakia). Dept. of Microelectronics; Feldhoff, Armin [Leibniz Univ. Hannover (Germany). Inst. fuer Physikalische Chemie und Elektrochemie; Gock, Eberhard [Technical Univ. Clausthal, Clausthal-Zellerfeld (Germany). Inst. of Mineral and Waste Processing and Dumping Technology

    2011-04-15

    Mechanochemical synthesis of lead selenide PbSe nanoparticles was performed by high-energy milling of lead and selenium powder in a laboratory planetary ball mill and in an industrial eccentric vibratory mill. Structural properties of the synthesized lead selenide were characterized using X-ray diffraction that confirmed crystalline nature of PbSe nanoparticles. The average size of PbSe crystallites of 37 nm was calculated from X-ray diffraction data using the Williamson-Hall method. The methods of particle size distribution analysis, specific surface area measurement, scanning electron microscopy and transmission electron microscopy were used for characterization of surface, mean particle size, and morphology of PbSe. An application of industrial mill verified a possibility of the synthesis of a narrow bandgap semiconductor PbSe at ambient temperature and in a relatively short reaction time. (orig.)

  7. Strukturelle und kinetische Charakterisierung von Ruthenium-Selenid Katalysatoren

    OpenAIRE

    Racz, Alexander

    2011-01-01

    Die Arbeit befasst sich mit Kohlenstoff-geträgerten Ruthenium-Selenid (RuSex) Katalysatoren für die kathodische Sauerstoffreduktion in Methanol-Brennstoffzellen. Ziel dieser Arbeit war es, RuSex/C Katalysatoren zu synthetisieren, welche eine vergleichbare elektrochemische Aktivität wie kommerzielle Pt/C Katalysatoren aufweisen. Neben der Optimierung der Synthese stand die elektrochemische Charakterisierung der Katalysatoren im Hinblick auf die elektrochemisch aktive Oberfläche, sowie deren Ak...

  8. Synthesis of cadmium selenide colloidal quantum dots in aquatic medium

    International Nuclear Information System (INIS)

    Cadmium selenide nanocrystals were prepared in water phase through facile wet chemistry technique with thioglycolic acid (TGA) acting as capping agent. Structures were characterized using X-ray diffraction (XRD), UV-vis absorption and photoluminescence spectroscopies. Depending on synthesis conditions nanoparticles exhibit photoluminescence with maximum in the region of 580 – 680 nm. Influence of technological parameters and component concentrations on nanocrystals average size and properties was studied

  9. Selenide-Based Electrocatalysts and Scaffolds for Water Oxidation Applications

    KAUST Repository

    Xia, Chuan

    2015-11-05

    Selenide-based electrocatalysts and scaffolds on carbon cloth are successfully fabricated and demonstrated for enhanced water oxidation applications. A max­imum current density of 97.5 mA cm−2 at an overpotential of a mere 300 mV and a small Tafel slope of 77 mV dec−1 are achieved, suggesting the potential of these materials to serve as advanced oxygen evolution reaction catalysts.

  10. Long-term physical ageing in vitreous arsenic selenides

    International Nuclear Information System (INIS)

    Effects of long-term physical aging (approx 20 years) studied in vitreous arsenic selenides using differential scanning calorimetry are compared with conventional short-term physical aging (up to 1 year). It is shown that these effects differ not only by their amplitudes but also by compositional dependences. These results clearly testify in a favour of a sufficient difference in microstructural origin for short- and long-term physical aging in chalcogenide glasses

  11. Raman study of gallium selenide single crystal oxidation

    Directory of Open Access Journals (Sweden)

    O.A. Balitskii

    2001-06-01

    Full Text Available The Raman investigations on thermally oxidized gallium selenide were conducted. It was established that the oxidation of the GaSe involves the formation of a-modification of Ga2Se3 at the temperature up to 450 °C. The Ga-(O2 complexes are also detected at this temperature but the formation of crystalline gallium oxide takes place at the temperature of 800°C

  12. The unexpected properties of alkali metal iron selenide superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Dagotto, Elbio R [ORNL

    2013-01-01

    The iron-based superconductors that contain FeAs layers as the fundamental building block in the crystal structures have been rationalized in the past using ideas based on the Fermi surface nesting of hole and electron pockets when in the presence of weak Hubbard U interactions. This approach seemed appropriate considering the small values of the magnetic moments in the parent compounds and the clear evidence based on photoemission experiments of the required electron and hole pockets. However, recent results in the context of alkali metal iron selenides, with generic chemical composition AxFe2ySe2 (A alkali metal element), have challenged those previous ideas since at particular compositions y the low-temperature ground states are insulating and display antiferromagnetic order with large iron magnetic moments. Moreover, angle-resolved photoemission studies have revealed the absence of hole pockets at the Fermi level in these materials. The present status of this exciting area of research, with the potential to alter conceptually our understanding of the ironbased superconductors, is here reviewed, covering both experimental and theoretical investigations. Other recent related developments are also briefly reviewed, such as the study of selenide two-leg ladders and the discovery of superconductivity in a single layer of FeSe. The conceptual issues considered established for the alkali metal iron selenides, as well as several issues that still require further work, are discussed.

  13. Sodium selenide toxicity is mediated by O2-dependent DNA breaks.

    Directory of Open Access Journals (Sweden)

    Gérald Peyroche

    Full Text Available Hydrogen selenide is a recurrent metabolite of selenium compounds. However, few experiments studied the direct link between this toxic agent and cell death. To address this question, we first screened a systematic collection of Saccharomyces cerevisiae haploid knockout strains for sensitivity to sodium selenide, a donor for hydrogen selenide (H(2Se/HSe(-/Se(2-. Among the genes whose deletion caused hypersensitivity, homologous recombination and DNA damage checkpoint genes were over-represented, suggesting that DNA double-strand breaks are a dominant cause of hydrogen selenide toxicity. Consistent with this hypothesis, treatment of S. cerevisiae cells with sodium selenide triggered G2/M checkpoint activation and induced in vivo chromosome fragmentation. In vitro, sodium selenide directly induced DNA phosphodiester-bond breaks via an O(2-dependent reaction. The reaction was inhibited by mannitol, a hydroxyl radical quencher, but not by superoxide dismutase or catalase, strongly suggesting the involvement of hydroxyl radicals and ruling out participations of superoxide anions or hydrogen peroxide. The (•OH signature could indeed be detected by electron spin resonance upon exposure of a solution of sodium selenide to O(2. Finally we showed that, in vivo, toxicity strictly depended on the presence of O(2. Therefore, by combining genome-wide and biochemical approaches, we demonstrated that, in yeast cells, hydrogen selenide induces toxic DNA breaks through an O(2-dependent radical-based mechanism.

  14. Sodium selenide toxicity is mediated by O2-dependent DNA breaks.

    Science.gov (United States)

    Peyroche, Gérald; Saveanu, Cosmin; Dauplais, Marc; Lazard, Myriam; Beuneu, François; Decourty, Laurence; Malabat, Christophe; Jacquier, Alain; Blanquet, Sylvain; Plateau, Pierre

    2012-01-01

    Hydrogen selenide is a recurrent metabolite of selenium compounds. However, few experiments studied the direct link between this toxic agent and cell death. To address this question, we first screened a systematic collection of Saccharomyces cerevisiae haploid knockout strains for sensitivity to sodium selenide, a donor for hydrogen selenide (H(2)Se/HSe(-/)Se(2-)). Among the genes whose deletion caused hypersensitivity, homologous recombination and DNA damage checkpoint genes were over-represented, suggesting that DNA double-strand breaks are a dominant cause of hydrogen selenide toxicity. Consistent with this hypothesis, treatment of S. cerevisiae cells with sodium selenide triggered G2/M checkpoint activation and induced in vivo chromosome fragmentation. In vitro, sodium selenide directly induced DNA phosphodiester-bond breaks via an O(2)-dependent reaction. The reaction was inhibited by mannitol, a hydroxyl radical quencher, but not by superoxide dismutase or catalase, strongly suggesting the involvement of hydroxyl radicals and ruling out participations of superoxide anions or hydrogen peroxide. The (•)OH signature could indeed be detected by electron spin resonance upon exposure of a solution of sodium selenide to O(2). Finally we showed that, in vivo, toxicity strictly depended on the presence of O(2). Therefore, by combining genome-wide and biochemical approaches, we demonstrated that, in yeast cells, hydrogen selenide induces toxic DNA breaks through an O(2)-dependent radical-based mechanism. PMID:22586468

  15. 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

  16. Separation of traffic related antimony compounds

    International Nuclear Information System (INIS)

    Complete text of publication follows. It is known that most of the brake pads contain Sb2S3 as lubricant to achieve better friction stability. Due to braking the brake lining crumbles away and its Sb content gets into the air. As a result of the temperature increase accompanying the braking a part of the antimony may oxidize to oxides, as Sb2O3 or even to the more stable form, Sb2O4. Since Sb2O3 more readily soluble than the others, its absorption from the lung so its environmental impact effect is more harmful. After a systematic investigation involving solubilization of the solid compounds, citric and tartaric acid as well as 6 mol/dm3 HCl were tested for leaching of trace antimony compounds from natural matrix. To prepare reference material related to these species, soil and activated charcoal was spiked in 10 μg/g concentration with all the three material (Sb2S3, Sb2O3,Sb2O4). separately. Recovery of the different forms was checked by graphite furnace atomic absorption spectrometric (GFAAS) analysis of the leachates. The soil was confirmed to oxidize the sulfide content while the activated charcoal was established to enrich antimony from HCl solution as ion association complex. It was concluded, that Sb2S3 is leached only in slight amount in 4 hours by 0.1-0.5 mol/dm3 citric acid, while leaching of Sb2O3 is quantitative. On the other side, it was proved that Sb2O3 as well as Sb2S3 traces are soluble in 6 HCl solution in 60 min, whilst Sb2O4 is not destroyed. So, the Sb2O3 and Sb2S3 content of a flying dust can be determined. The GFAAS temperature program had to be modified in order to be capable to analyze high organic matrix as citric or tartaric acid even in 0.5 mol/dm3 concentration. Concerning their decomposition temperature an additional step was inserted into the temperature program, pyrolysis on 300 and 400 deg C, respectively. The antimony concentration of the highly acidic leachates were determined by hydride generation GFAAS. The reproducibility of

  17. Double-Diffusive Convection During Growth of Halides and Selenides

    Science.gov (United States)

    Singh, N. B.; Su, Ching-Hua; Duval, Walter M. B.

    2015-01-01

    Heavy metal halides and selenides have unique properties which make them excellent materials for chemical, biological and radiological sensors. Recently it has been shown that selenohalides are even better materials than halides or selenides for gamma-ray detection. These materials also meet the strong needs of a wide band imaging technology to cover ultra-violet (UV), midwave infrared wavelength (MWIR) to very long wavelength infrared (VLWIR) region for hyperspectral imager components such as etalon filters and acousto-optic tunable filters (AO). In fact AOTF based imagers based on these materials have some superiority than imagers based on liquid crystals, FTIR, Fabry-Perot, grating, etalon, electro-optic modulation, piezoelectric and several other concepts. For example, broadband spectral and imagers have problems of processing large amount of information during real-time observation. Acousto-Optic Tunable Filter (AOTF) imagers are being developed to fill the need of reducing processing time of data, low cost operation and key to achieving the goal of covering long-wave infrared (LWIR). At the present time spectral imaging systems are based on the use of diffraction gratings are typically used in a pushbroom or whiskbroom mode. They are mostly used in systems and acquire large amounts of hyperspectral data that is processed off-line later. In contrast, acousto-optic tunable filter spectral imagers require very little image processing, providing new strategies for object recognition and tracking. They are ideally suited for tactical situations requiring immediate real-time image processing. But the performance of these imagers depends on the quality and homogeneity of acousto-optic materials. In addition for many systems requirements are so demanding that crystals up to sizes of 10 cm length are desired. We have studied several selenides and halide crystals for laser and AO imagers for MWIR and LWIR wavelength regions. We have grown and fabricated crystals of

  18. Electrochemical synthesis of alkali-intercalated iron selenide superconductors

    Institute of Scientific and Technical Information of China (English)

    申士杰; 应天平; 王刚; 金士锋; 张韩; 林志萍; 陈小龙

    2015-01-01

    Electrochemical method has been used to insert K/Na into FeSe lattice to prepare alkali-intercalated iron selenides at room temperature. Magnetization measurement reveals that KxFe2Se2 and NaxFe2Se2 are superconductive at 31 K and 46 K, respectively. This is the first successful report of obtaining metal-intercalated FeSe-based high-temperature superconductors using electrochemical method. It provides an effective route to synthesize metal-intercalated layered compounds for new superconductor exploration.

  19. Synthesis and characterization of cuprous selenide nanocrystals at room temperature

    Institute of Scientific and Technical Information of China (English)

    Tai Shan Li; Shao Pu Liu; Zhao Xia Lu; Zhong Fang Liu

    2007-01-01

    A simple method has been developed to prepare cuprous selenide nanocrystals by the reaction of copper nitrate trihydrate with selenium and sodium mercaptoacetate in aqueous ammonia system. Cu2Se nanocrystals were characterized by transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), electron diffraction (ED), fluorescence spectrum and ultraviolet-visible absorption spectrum. Cu2Se nanocrystals showed berzelianite structure with 20-40 nm in length and 10-20 nm in width. A possible mechanism is also discussed.

  20. Selective determination of antimony(III) and antimony(V) with ammonium pyrrolidinedithiocarbamate, sodium diethyldithiocarbamate and dithizone by atomic-absorption spectrometry with a carbon-tube atomizer.

    Science.gov (United States)

    Kamada, T; Yamamoto, Y

    1977-05-01

    The extraction behaviour of antimony(III) and antimony(V) with ammonium pyrrolidinedithiocarbamate, sodium diethyldithiocarbamate and dithizone in organic solvents has been investigated by means of frameless atomic-absorption spectrophotometry with a carbon-tube atomizer. The selective extraction of antimony(III) and differential determination of antimony(III) and antimony(V) have been developed. With ammonium pyrrolidinedithiocarbamate and methyl isobutyl ketone, when the aqueous phase/solvent volume ratio is 50 ml/10 ml and the injection volume in the carbon tube is 20 mul, the sensitivity for antimony is 0.2 ng/ml for 1% absorption. The relative standard deviations are ca. 2%. Interferences by many metal ions can be prevented by masking with EDTA. The proposed methods have been applied satisfactorily to determination of antimony(III) and antimony(V) in various types of water. PMID:18962096

  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. Film growth mechanism for electrodeposited copper indium selenide compounds

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yan, E-mail: yli@interphases.com; Shaikh, Shahid S., E-mail: ssshaikh@gmail.com; Menezes, Shalini, E-mail: smenezes@interphases.com

    2012-12-01

    The Cu{sub 2}Se-In{sub 2}Se{sub 3} system comprises several copper indium selenide (CIS) compounds with solar-matched bandgaps along with the optimum properties of the CuInSe{sub 2} compound. This work investigates electrochemical growth of CIS films under various conditions, initially identified with cyclic voltammetry. The film growth, monitored with X-ray fluorescence analysis, shows excellent composition and thickness uniformity. The results agree with secondary ion mass spectroscopy profiles and X-ray diffraction data, indicating the conversion of initially formed binary phases to homogenous ternary compound. Deposition potential and substrate/electrolyte interface control the film formation mechanism and hence its composition. Electrolyte composition and agitation influence the film thickness. Judicious combination of process parameters is essential to obtain CIS films with optimum properties. - Highlights: Black-Right-Pointing-Pointer In-rich copper indium selenide (CIS) compounds offer wide bandgaps. Black-Right-Pointing-Pointer Electrodeposition leads to excellent composition and thickness uniformity. Black-Right-Pointing-Pointer Initial binary phases convert to homogenous ternary compound. Black-Right-Pointing-Pointer Thermodynamic driving force leads to self stabilizing stoichiometries. Black-Right-Pointing-Pointer Process parameter control enables optimizing CIS film properties.

  3. Deposition of rod-shaped antimony sulfide thin films from single-source antimony thiosemicarbazone precursors

    Energy Technology Data Exchange (ETDEWEB)

    Biswal, Jasmine B.; Sawant, Narayan V. [Department of Chemistry, University of Mumbai, Vidyanagari, Santacruz (East), Mumbai - 400 098 (India); Garje, Shivram S., E-mail: ssgarje@chem.mu.ac.i [Department of Chemistry, University of Mumbai, Vidyanagari, Santacruz (East), Mumbai - 400 098 (India)

    2010-04-02

    Antimony sulfide thin films were deposited on glass substrates by aerosol assisted chemical vapour deposition technique using single source precursors, namely, antimony(III) thiosemicarbazones, SbCl{sub 3}(L) (L = thiosemicarbazones of thiophene-2-carboxaldehyde (1) and cinnamaldehyde (2)). The deposited films were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis and UV-visible spectroscopy in order to identify their phases, morphologies, compositions and optical properties respectively. These characterizations revealed that the films were comprised of rod-shaped particles of orthorhombic stibnite (Sb{sub 2}S{sub 3}) with a Sb:S stoichiometry of {approx} 1:1.3. The calculated optical band gap from UV-vis absorption spectrum is found to be 3.48 eV.

  4. Tissue distribution of residual antimony in rats treated with multiple doses of meglumine antimoniate

    Directory of Open Access Journals (Sweden)

    Deise Riba Coelho

    2014-07-01

    Full Text Available Meglumine antimoniate (MA and sodium stibogluconate are pentavalent antimony (SbV drugs used since the mid-1940s. Notwithstanding the fact that they are first-choice drugs for the treatment of leishmaniases, there are gaps in our knowledge of their toxicological profile, mode of action and kinetics. Little is known about the distribution of antimony in tissues after SbV administration. In this study, we evaluated the Sb content of tissues from male rats 24 h and three weeks after a 21-day course of treatment with MA (300 mg SbV/kg body wt/d, subcutaneous. Sb concentrations in the blood and organs were determined by inductively coupled plasma-mass spectrometry. In rats, as with in humans, the Sb blood levels after MA dosing can be described by a two-compartment model with a fast (t1/2 = 0.6 h and a slow (t1/2 >> 24 h elimination phase. The spleen was the organ that accumulated the highest amount of Sb, while bone and thyroid ranked second in descending order of tissues according to Sb levels (spleen >> bone, thyroid, kidneys > liver, epididymis, lungs, adrenals > prostate > thymus, pancreas, heart, small intestines > skeletal muscle, testes, stomach > brain. The pathophysiological consequences of Sb accumulation in the thyroid and Sb speciation in the liver, thyroid, spleen and bone warrant further studies.

  5. How can we adapt to geological scarcity of antimony? Investigation of antimony's substitutability and of other measures to achieve a sustainable use

    NARCIS (Netherlands)

    Henckens, M.L.C.M.; Driessen, P.P.J.; Worrell, E.

    2016-01-01

    Abstract Antimony is an element that is applied in many useful applications for mankind. However, antimony resources are very scarce, when comparing the current extraction rates with the availability of antimony containing ores. From an inter-temporal sustainability perspective, current generations

  6. Polystyrene-supported Benzyl Selenide: An Efficient Reagent for Highly Stereocontrolled Synthesis of Substituted Olefins

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Polystyrene-supported benzyl selenide has been prepared. This novel reagent was treated with LDA to produce a selenium stabilized carbanion, which reacted with alkyl halide, followed by selenoxide syn-elimination, to give substituted olefins stereospecificly.

  7. Manipulation of cadmium selenide nanorods with an atomic force microscope

    International Nuclear Information System (INIS)

    We have used an atomic force microscope (AFM) to manipulate and study ligand-capped cadmium selenide nanorods deposited on highly oriented pyrolitic graphite (HOPG). The AFM tip was used to manipulate (i.e., translate and rotate) the nanorods by applying a force perpendicular to the nanorod axis. The manipulation result was shown to depend on the point of impact of the AFM tip with the nanorod and whether the nanorod had been manipulated previously. Forces applied parallel to the nanorod axis, however, did not give rise to manipulation. These results are interpreted by considering the atomic-scale interactions of the HOPG substrate with the organic ligands surrounding the nanorods. The vertical deflection of the cantilever was recorded during manipulation and was combined with a model in order to estimate the value of the horizontal force between the tip and nanorod during manipulation. This horizontal force is estimated to be on the order of a few tens of nN.

  8. Selenide isotope generator for the Galileo Mission. Program final report

    Energy Technology Data Exchange (ETDEWEB)

    1979-06-01

    This final report for the Selenide Isotope Generator for the Galileo Mission (SIG/GM) documents the work performed by Teledyne Energy Systems (TES) under US Department of Energy (DOE) Contract No. DE-AC01-78ET33009 (formerly ET-78-C-01-2865) during the period April 10, 1978 to June 30, 1979. Because of technical difficulties with the thermoelectric converter being developed by the 3M Company under separate DOE contract, a Stop Work Order, dated January 29, 1979, was issued by DOE. The TES effort up to the receipt of the Stop Work Order as well as limited technical activities up to the contract conclusion on June 30, 1979 are reported.

  9. Electrochemical synthesis of alkali-intercalated iron selenide superconductors

    Science.gov (United States)

    Shen, Shi-Jie; Ying, Tian-Ping; Wang, Gang; Jin, Shi-Feng; Zhang, Han; Lin, Zhi-Ping; Chen, Xiao-Long

    2015-11-01

    Electrochemical method has been used to insert K/Na into FeSe lattice to prepare alkali-intercalated iron selenides at room temperature. Magnetization measurement reveals that KxFe2Se2 and NaxFe2Se2 are superconductive at 31 K and 46 K, respectively. This is the first successful report of obtaining metal-intercalated FeSe-based high-temperature superconductors using electrochemical method. It provides an effective route to synthesize metal-intercalated layered compounds for new superconductor exploration. Project supported by the National Natural Science Foundation of China (Grant Nos. 51322211and 91422303), the Strategic Priority Research Program (B) of the Chinese Academy of Sciences (Grant No. XDB07020100), Beijing Nova Program of China (Grant No. 2011096), and K. C. Wong Education Foundation, Hong Kong, China.

  10. Selenide isotope generator for the Galileo mission. Reliability program plan

    International Nuclear Information System (INIS)

    The reliability program plan for the Selenide Isotope Generator (SIG) program is presented. It delineates the specific tasks that will be accomplished by Teledyne Energy Systems and its suppliers during design, development, fabrication and test of deliverable Radioisotopic Thermoelectric Generators (RTG), Electrical Heated Thermoelectric Generators (ETG) and associated Ground Support Equipment (GSE). The Plan is formulated in general accordance with procedures specified in DOE Reliability Engineering Program Requirements Publication No. SNS-2, dated June 17, 1974. The Reliability Program Plan presented herein defines the total reliability effort without further reference to Government Specifications. The reliability tasks to be accomplished are delineated herein and become the basis for contract compliance to the extent specified in the SIG contract Statement of Work

  11. Thermal lensing in silver gallium selenide parametric oscillator crystals.

    Science.gov (United States)

    Marquardt, C L; Cooper, D G; Budni, P A; Knights, M G; Schepler, K L; Dedomenico, R; Catella, G C

    1994-05-20

    We performed an experimental investigation of thermal lensing in silver gallium selenide (AgGaSe(2)) optical parametric oscillator crystals pumped by a 2-µm laser at ambient temperature. We determined an empirical expression for the effective thermal focusing power in terms of the pump power, beam diameter, crystal length, and absorption coefficient. This relation may be used to estimate average power limitations in designing AgGaSe(2) optical parametric oscillators. We also demonstrated an 18% slope efficiency from a 2-µm pumped AgGaSe(2) optical parametric oscillator operated at 77 K, at which temperature thermal lensing is substantially reduced because of an increase in the thermal conductivity and a decrease in the thermal index gradient dn/dT. Cryogenic cooling may provide an additional option for scaling up the average power capability of a 2-µm pumped AgGaSe(2) optical parametric oscillator.

  12. Potentiostatic Electrochemical Preparation and Characterisation of Aluminium Containing Nickel Selenide

    Directory of Open Access Journals (Sweden)

    Sandeep Gohar

    2014-01-01

    Full Text Available The wide range of properties exhibited by Al based alloy makes them suitable for different applications. Aluminium containing nickel Selenide ternary alloy possess considerable corrosion resistance as compared to their pure metal counterparts. The objective of the present work has been focused on the preparation and characterisation of its thin film. Alloying with Aluminium improve the oxidation resistance and increases the heat conductivity of the alloy. There is always a high demand for plating Al and its alloys in automotive and aerospace products, house-hold goods, and artificial jewellery etc,. The morphological and the structural studies of the electrodeposited thin film were determined by Scanning Electron Microscope (SEM images and X-Ray Diffraction Pattern (XRD while elemental composition has been done by Energy Dispersive X-Ray Spectroscopy (EDAX analysis.

  13. Cloud point extraction combined with electrothermal atomic absorption spectrometry for the speciation of antimony(III) and antimony(V) in food packaging materials

    International Nuclear Information System (INIS)

    A simple, sensitive method for the speciation of inorganic antimony by cloud point extraction combined with electrothermal atomic absorption spectrometry (ETAAS) is presented and evaluated. The method based on the fact that formation of a hydrophobic complex of antimony(III) with ammonium pyrrolidine dithiocarbamate (APDC) at pH 5.0 and subsequently the hydrophobic complex enter into surfactant-rich phase, whereas antimony(V) remained in aqueous solutions. Antimony(III) in surfactant-rich phase was analyzed by ETAAS after dilution by 0.2 mL nitric acid in methanol (0.1 M), and antimony(V) was calculated by subtracting antimony(III) from the total antimony after reducing antimony(V) to antimony(III) by L-cysteine. The main factors affecting the cloud point extraction, such as pH, concentration of APDC and Triton X-114, equilibrium temperature and incubation time, sample volume were investigated in detail. Under the optimum conditions, the detection limit (3σ) of the proposed method was 0.02 ng mL-1 for antimony(III), and the relative standard deviation was 7.8% (c = 1.0 ng mL-1, n = 7). The proposed method was successfully applied to speciation of inorganic antimony in the leaching solutions of different food packaging materials with satisfactory results.

  14. Cloud point extraction combined with electrothermal atomic absorption spectrometry for the speciation of antimony(III) and antimony(V) in food packaging materials.

    Science.gov (United States)

    Jiang, Xiuming; Wen, Shengping; Xiang, Guoqiang

    2010-03-15

    A simple, sensitive method for the speciation of inorganic antimony by cloud point extraction combined with electrothermal atomic absorption spectrometry (ETAAS) is presented and evaluated. The method based on the fact that formation of a hydrophobic complex of antimony(III) with ammonium pyrrolidine dithiocarbamate (APDC) at pH 5.0 and subsequently the hydrophobic complex enter into surfactant-rich phase, whereas antimony(V) remained in aqueous solutions. Antimony(III) in surfactant-rich phase was analyzed by ETAAS after dilution by 0.2 mL nitric acid in methanol (0.1M), and antimony(V) was calculated by subtracting antimony(III) from the total antimony after reducing antimony(V) to antimony(III) by l-cysteine. The main factors affecting the cloud point extraction, such as pH, concentration of APDC and Triton X-114, equilibrium temperature and incubation time, sample volume were investigated in detail. Under the optimum conditions, the detection limit (3 sigma) of the proposed method was 0.02 ng mL(-1) for antimony(III), and the relative standard deviation was 7.8% (c=1.0 ng mL(-1), n=7). The proposed method was successfully applied to speciation of inorganic antimony in the leaching solutions of different food packaging materials with satisfactory results. PMID:19853991

  15. Cloud point extraction combined with electrothermal atomic absorption spectrometry for the speciation of antimony(III) and antimony(V) in food packaging materials

    Energy Technology Data Exchange (ETDEWEB)

    Jiang Xiuming; Wen Shengping [School of Chemistry and Chemical Engineering, Henan University of Technology, South Song Shan Road No. 140, Zhengzhou City 450001 (China); Xiang Guoqiang, E-mail: xianggq@haut.edu.cn [School of Chemistry and Chemical Engineering, Henan University of Technology, South Song Shan Road No. 140, Zhengzhou City 450001 (China)

    2010-03-15

    A simple, sensitive method for the speciation of inorganic antimony by cloud point extraction combined with electrothermal atomic absorption spectrometry (ETAAS) is presented and evaluated. The method based on the fact that formation of a hydrophobic complex of antimony(III) with ammonium pyrrolidine dithiocarbamate (APDC) at pH 5.0 and subsequently the hydrophobic complex enter into surfactant-rich phase, whereas antimony(V) remained in aqueous solutions. Antimony(III) in surfactant-rich phase was analyzed by ETAAS after dilution by 0.2 mL nitric acid in methanol (0.1 M), and antimony(V) was calculated by subtracting antimony(III) from the total antimony after reducing antimony(V) to antimony(III) by L-cysteine. The main factors affecting the cloud point extraction, such as pH, concentration of APDC and Triton X-114, equilibrium temperature and incubation time, sample volume were investigated in detail. Under the optimum conditions, the detection limit (3{sigma}) of the proposed method was 0.02 ng mL{sup -1} for antimony(III), and the relative standard deviation was 7.8% (c = 1.0 ng mL{sup -1}, n = 7). The proposed method was successfully applied to speciation of inorganic antimony in the leaching solutions of different food packaging materials with satisfactory results.

  16. Hollow Cobalt Selenide Microspheres: Synthesis and Application as Anode Materials for Na-Ion Batteries.

    Science.gov (United States)

    Ko, You Na; Choi, Seung Ho; Kang, Yun Chan

    2016-03-16

    The electrochemical properties of hollow cobalt oxide and cobalt selenide microspheres are studied for the first time as anode materials for Na-ion batteries. Hollow cobalt oxide microspheres prepared by one-pot spray pyrolysis are transformed into hollow cobalt selenide microspheres by a simple selenization process using hydrogen selenide gas. Ultrafine nanocrystals of Co3O4 microspheres are preserved in the cobalt selenide microspheres selenized at 300 °C. The initial discharge capacities for the Co3O4 and cobalt selenide microspheres selenized at 300 and 400 °C are 727, 595, and 586 mA h g(-1), respectively, at a current density of 500 mA g(-1). The discharge capacities after 40 cycles for the same samples are 348, 467, and 251 mA h g(-1), respectively, and their capacity retentions measured from the second cycle onward are 66, 91, and 50%, respectively. The hollow cobalt selenide microspheres have better rate performances than the hollow cobalt oxide microspheres. PMID:26918934

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

    International Nuclear Information System (INIS)

    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-1). 140 mg of yeast and 2 h of contact were necessary to ensure quantitative sequestration of Sb(III) up to 750 μg L-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-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-1, respectively, using ICP-MS, 7 and 0.9 μg L-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 μg L-1 level and less than 10% at the lowest Sb(III) and Sb(V) tested concentration (0.1 μg L-1). Corrected recoveries were in all cases close to 100%

  18. Noninferiority of Miltefosine Versus Meglumine Antimoniate for Cutaneous Leishmaniasis in Children

    OpenAIRE

    Rubiano, Luisa Consuelo; Miranda, María Consuelo; Muvdi Arenas, Sandra; Montero, Luz Mery; Rodríguez-Barraquer, Isabel; Garcerant, Daniel; Prager, Martín; Osorio, Lyda; Rojas, Maria Ximena; Pérez, Mauricio; Nicholls, Ruben Santiago; Gore Saravia, Nancy

    2012-01-01

    Background. Children have a lower response rate to antimonial drugs and higher elimination rate of antimony (Sb) than adults. Oral miltefosine has not been evaluated for pediatric cutaneous leishmaniasis.

  19. The influence of pet containers on antimony concentration in bottled drinking water

    OpenAIRE

    Perić-Grujić Aleksandra A.; Radmanovac Aleksandar R.; Stojanov Aleksander M.; Pocajt Viktor V.; Ristić Mirjana Đ.

    2010-01-01

    Antimony trioxide (Sb2O3) is the most frequently used catalyst in the polyethylene terephthalate (PET) manufacture. As a result, antimony is incorporated into PET bottles at concentration level of 100-300 mg/kg. PET containers are used for drinking water and beverages, as well as food packaging and in the pharmaceutical industry. Thus, it is important to understand the factors that may influence the release of antimony from the catalysts into water and other products, since antimony is potent...

  20. The influence of pet containers on antimony concentration in bottled drinking water

    Directory of Open Access Journals (Sweden)

    Perić-Grujić Aleksandra A.

    2010-01-01

    Full Text Available Antimony trioxide (Sb2O3 is the most frequently used catalyst in the polyethylene terephthalate (PET manufacture. As a result, antimony is incorporated into PET bottles at concentration level of 100-300 mg/kg. PET containers are used for drinking water and beverages, as well as food packaging and in the pharmaceutical industry. Thus, it is important to understand the factors that may influence the release of antimony from the catalysts into water and other products, since antimony is potentially toxic trace element. In this paper, the antimony content in nine brands of bottled mineral and spring water from Serbia, and seven brands of bottled mineral and spring water from EU countries was analyzed. The measurements were conducted using the inductively coupled plasma-mass spectrometry (ICP-MS technique. In the all examined samples the antimony concentration was bellow the maximum contaminant level of 5 μg/L prescribed by the Serbian and EU regulations. Comparison of the content of antimony in PET bottled waters with the content of antimony in water bottled commercially in glass and the natural content of antimony in pristine groundwaters, provides explicit evidence of antimony leaching from PET containers. Since waters bottled in PET have much greater concentration ratio of Sb to Pb than corresponding pristine groundwaters, it can be assumed that bottled waters cannot be used as the relavant source for the study of the natural antimony content in groundwaters. There is a clear relation between the quality of water in bottles (composition, ion strength and antimony leaching rate. Moreover, while the rate of antimony leaching is slow at temperatures below 60 oC, at the temperature range of 60-80 oC antimony release occurs and reaches maximum contaminant level rapidly. As antimony can cause both acute and chronic health problems, factors that promote the increase of antimony concentration should be avoided.

  1. Antimony Doped Tin Oxide Thin Films: Co Gas Sensor

    Directory of Open Access Journals (Sweden)

    P.S. Joshi

    2011-01-01

    Full Text Available Tin dioxide (SnO2 serves as an important base material in a variety of resistive type gas sensors. The widespread applicability of this semicoducting oxide is related both to its range of conductance variability and to the fact that it responds to both oxidising and reducing gases. The antimony doped tin-oxide films were prepared by spray pyrolysis method. The as-deposited films are blackish in colour. Addition of antimony impurity showed little increase in the thickness. The X-ray diffraction pattern shows characteristic tin oxide peaks with tetragonal structure. As the doping concentration of antimony was increased, new peak corresponding to Sb was observed. The intensity of this peak found to be increased when the Sb concentration was increased from 0.01 % to the 1 % which indicates the antimony was incorporated into the tin oxide. For gas sensing studies ohmic contacts were preferred to ensure the changes in resistance of sensor is due to only adsorption of gas molecule. The graph of I-V shows a straight line in nature which indicates the ohmic contact. The sensitivity of the sensor for CO gas was tested. The sensitivity of antimony doped tin oxide found to be increased with increasing Sb concentration. The maximum sensitivity was observed for Sb = 1 % at a working temperature of 250 °C.

  2. Behavior of arsenic impurity at antimony electric precipitation

    International Nuclear Information System (INIS)

    In the paper the arsenic impurity electrochemical behavior and it purification from antimony by electric precipitation out of fluoride solutions was studied. For this the arsenic sample with mass 0.003-0.006 g has been irradiated at the WWR-SM nuclear reactor during 3-5 hour in the thermal neutron flux 1013 n/cm2 s, after 24 h keeping the sample has being dissolved in the concentrated nitric acid, and then it has been evaporated several times with distillation water addition up to wet precipitation state. It is shown, that arsenic impurity behavior character in the antimony electric precipitation out to fluoride electrolyte depends on the electrolyte content, electrolysis conditions, arsenic valency state in arsenic impurity existence in the five-valency state its joint electric reduction with antimony is practically not observing. In the case the arsenic being in three-valency state, it joint electric reduction with antimony is taking place. In this time the electrolytic antimony contents arsenic impurities less in dozen time than initial material

  3. Martensite transformation in antimony implanted stainless steel

    International Nuclear Information System (INIS)

    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 1020 ions/m2, 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.)

  4. Antimony Resistance in Leishmania, Focusing on Experimental Research

    Directory of Open Access Journals (Sweden)

    Fakhri Jeddi

    2011-01-01

    Full Text Available Leishmaniases are parasitic diseases that spread in many countries with a prevalence of 12 million cases. There are few available treatments and antimonials are still of major importance in the therapeutic strategies used in most endemic regions. However, resistance toward these compounds has recently emerged in areas where the replacement of these drugs is mainly limited by the cost of alternative molecules. In this paper, we reviewed the studies carried out on antimonial resistance in Leishmania. Several common limitations of these works are presented before prevalent approaches to evidence antimonial resistance are related. Afterwards, phenotypic determination of resistance is described, then confronted to clinical outcome. Finally, we detail molecular mechanisms and targets involved in resistance and already identified in vitro within selected mutant strains or in clinical isolates.

  5. Structure and photoluminescence of molybdenum selenide nanomaterials grown by hot filament chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Wang, B.B. [College of Chemistry and Chemical Engineering, Chongqing University of Technology, 69 Hongguang Rd, Lijiatuo, Banan District, Chongqing 400054 (China); Plasma Nanoscience Laboratories, Manufacturing Flagship, Commonwealth Scientific and Industrial Research Organization, P. O. Box 218, Lindfield, NSW 2070 (Australia); Zhu, M.K. [College of Materials Science and Engineering, Beijing University of Technology, Beijing 100124 (China); Ostrikov, K., E-mail: kostya.ostrikov@qut.edu.au [Plasma Nanoscience Laboratories, Manufacturing Flagship, Commonwealth Scientific and Industrial Research Organization, P. O. Box 218, Lindfield, NSW 2070 (Australia); Institute for Future Environments, School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Brisbane, QLD 4000 (Australia); Plasma Nanoscience, School of Physics, The University of Sydney, Sydney, NSW 2006 (Australia); Shao, R.W.; Zheng, K. [Institute of Microstructure and Properties of Advanced Materials, Beijing University of Technology, Beijing 100124 (China)

    2015-10-25

    Molybdenum selenide nanomaterials with different structures are synthesized on silicon substrates coated with gold films by hot filament chemical vapor deposition (HFCVD) in nitrogen environment, where molybdenum trioxide and selenium powders are used as source materials. The structure and composition of the synthesized molybdenum selenide nanomaterials are studied using field emission scanning electron microscopy, transmission electron microscopy, micro-Raman spectroscopy and X-ray photoelectron spectroscopy. The results indicate that the structures of molybdenum selenide change from nanoflakes to nanoparticles with the increase of content of molybdenum trioxide precursor. The photoluminescence (PL) excitation using the 325 nm line of He–Cd laser as the excitation source generates green light with the wavelength of about 512–516 nm. The formation of molybdenum selenide nanomaterials is determined by the decomposition rates of molybdenum trioxide in HFCVD. The possible factors that affect the generation of green PL bands are analyzed. These outcomes of this work enrich our knowledge on the synthesis of transition metal dichalcogenides and contribute to the development of applications of these materials in optoelectronic devices. - Highlights: • Molybdenum selenide nanoflakes, nanoparticles and hybrids produced by HFCVD. • Uncommon MoO{sub 3} and Se precursor co-location and mixing and effective MoO{sub 3} decomposition. • Morphology change from nanoflakes to nanoparticles with higher ratio of MoO{sub 3} precursor. • Strong photoluminescence emission of green light with a wavelength of ∼512–516 nm.

  6. Amorphous Indium Selenide Thin Films Prepared by RF Sputtering: Thickness-Induced Characteristics.

    Science.gov (United States)

    Han, Myoung Yoo; Park, Yong Seob; Kim, Nam-Hoon

    2016-05-01

    The influence of indium composition, controlled by changing the film thickness, on the optical and electrical properties of amorphous indium selenide thin films was studied for the application of these materials as Cd-free buffer layers in CI(G)S solar cells. Indium selenide thin films were prepared using RF magnetron sputtering method. The indium composition of the amorphous indium selenide thin films was varied from 94.56 to 49.72 at% by increasing the film thickness from 30 to 70 nm. With a decrease in film thickness, the optical transmittance increased from 87.63% to 96.03% and Eg decreased from 3.048 to 2.875 eV. Carrier concentration and resistivity showed excellent values of ≥1015 cm(-3) and ≤ 10(4) Ω x cm, respectively. The conductivity type of the amorphous indium selenide thin films could be controlled by changing the film-thickness-induced amount of In. These results indicate the possibility of tuning the properties of amorphous indium selenide thin films by changing their composition for use as an alternate buffer layer material in CI(G)S solar cells.

  7. Using different chemical methods for deposition of copper selenide thin films and comparison of their characterization.

    Science.gov (United States)

    Güzeldir, Betül; Sağlam, Mustafa

    2015-11-01

    Different chemical methods such as Successive Ionic Layer Adsorption and Reaction (SILAR), spin coating and spray pyrolysis methods were used to deposite of copper selenide thin films on the glass substrates. The films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), energy dispersive X-ray analysis (EDX) spectroscopy and UV-vis spectrophotometry. The XRD and SEM studies showed that all the films exhibit polycrystalline nature and crystallinity of copper selenide thin films prepared with spray pyrolysis greater than spin coating and SILAR methods. From SEM and AFM images, it was observed copper selenide films were uniform on the glass substrates without any visible cracks or pores. The EDX spectra showed that the expected elements exist in the thin films. Optical absorption studies showed that the band gaps of copper selenide thin films were in the range 2.84-2.93 eV depending on different chemical methods. The refractive index (n), optical static and high frequency dielectric constants (ε0, ε∞) values were calculated by using the energy bandgap values for each deposition method. The obtained results from different chemical methods revealed that the spray pyrolysis technique is the best chemical deposition method to fabricate copper selenide thin films. This absolute advantage was lead to play key roles on performance and efficiency electrochromic and photovoltaic devices. PMID:26037495

  8. Lattice dynamics of femtosecond laser-excited antimony

    Science.gov (United States)

    Abdel-Fattah, Mahmoud Hanafy; Bugayev, Aleksey; Elsayed-Ali, Hani E.

    2016-07-01

    Ultrafast electron diffraction is used to probe the lattice dynamics of femtosecond laser-excited antimony thin film. The temporal hierarchies of the intensity and position of diffraction orders are monitored. The femtosecond laser excitation of antimony film was found to lead to initial compression after the laser pulse, which gives way to tension vibrating at new equilibrium displacement. A damped harmonic oscillator model, in which the hot electron-blast force contributes to the driving force of oscillations in lattice spacing, is used to interpret the data. The electron-phonon energy-exchange rate and the electronic Grüneisen parameter were obtained.

  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. A magnetic x-ray diffraction investigation of gadolinium selenide

    Energy Technology Data Exchange (ETDEWEB)

    Costa, M.M.R.; Almeida, M.J.M. de [Departamento de Fisica, Universidade de Coimbra, Coimbra (Portugal); Nuttall, W.J.; Stirling, W.G. [Department of Physics, Keele University, Keele, Staffs (United Kingdom); Tang, C.C. [Daresbury Laboratory, Warrington, Cheshire (United Kingdom); Forsyth, J.B. [Rutherford Appleton Laboratory, Chilton, Oxon (United Kingdom); Cooper, M.J. [Department of Physics, University of Warwick, Coventry (United Kingdom)

    1996-04-01

    A single-crystal synchrotron radiation study of gadolinium selenide has been made in the temperature range 15-100 K. GdSe has the rocksalt structure and becomes antiferromagnetic below a reported Neel temperature of 65 K. At 15 K, magnetic reflections are observed at G+T with modulation wavevector T={l_brace}1/2:1/2:1/2{r_brace} propagating from reciprocal lattice point G. This is achieved by exploiting the resonant enhancement in the vicinity of the Gd L{sub II} and L{sub III} edges. Similar enhancements are observed at the two edges, with the maximum effect occurring approximately 3 eV above the absorption edge. The temperature dependence of the intensity of the magnetic reflections indicates a Neel temperature of 63(1) K. These measurements, together with high-resolution studies of the fundamental reflections (T=0), contribute further evidence of magnetic or structural changes in the sample at 37(1) K. Our observations are discussed and compared with previous x-ray diffraction and magnetic susceptibility measurements. (author)

  11. Magnetic properties of Cr telluride-selenide alloys

    Energy Technology Data Exchange (ETDEWEB)

    Mankovsky, Sergey; Polesya, Svetlana; Ebert, Hubert [Dept. Chemie und Biochemie, Universitaet Muenchen, Butenandtstr. 5-13, D-81377 Muenchen (Germany); Huang, Zhong-Le; Bensch, Wolfgang [Institute for Anorganic Chemistry, Olshausenstr. 40, D-24098, Kiel (Germany)

    2007-07-01

    Results of a theoretical study of the magnetic properties of Cr telluride-selenide alloys having trigonal crystal structure are presented in comparison with experimental results. Both ground state and temperature-dependent magnetic properties of Cr{sub 1-{delta}}Te and Cr{sub x}(Te{sub {alpha}}Se{sub {beta}}){sub 2} (with ratio {alpha}:{beta}=7:1,6:2,5:3) have been investigated in a wide region of chromium content. For the alloys Cr{sub x}(Te{sub {alpha}}Se{sub {beta}}){sub 2} a transition to the state with antiferromagnetic order in a fully occupied sub-lattice and with no order in a partially occupied sub-lattice was obtained. For the alloys Li{sub x}Cr{sub 0.5}Ti{sub 0.75}Se{sub 2}, a non-monotonic dependence of structural and magnetic properties have been found upon increase of Li concentration x, that is in agreement with experimental results. The ground state properties have been studied on the basis of electronic structure calculations using the Korringa-Kohn-Rostoker (KKR) band structure method combined with the CPA alloy theory. Using Monte Carlo simulations we obtained the magnetic configuration at T=0 K and studied the magnetic properties at T>0 K as well. The required exchange coupling parameters were obtained from our ab-initio electronic structure calculations.

  12. Antimony to Cure Visceral Leishmaniasis Unresponsive to Liposomal Amphotericin B.

    Directory of Open Access Journals (Sweden)

    Gloria Morizot

    2016-01-01

    Full Text Available We report on 4 patients (1 immunocompetent, 3 immunosuppressed in whom visceral leishmaniasis had become unresponsive to (or had relapsed after treatment with appropriate doses of liposomal amphotericin B. Under close follow-up, full courses of pentavalent antimony were administered without life-threatening adverse events and resulted in rapid and sustained clinical and parasitological cure.

  13. Antimony to Cure Visceral Leishmaniasis Unresponsive to Liposomal Amphotericin B.

    Science.gov (United States)

    Morizot, Gloria; Jouffroy, Romain; Faye, Albert; Chabert, Paul; Belhouari, Katia; Calin, Ruxandra; Charlier, Caroline; Miailhes, Patrick; Siriez, Jean-Yves; Mouri, Oussama; Yera, Hélène; Gilquin, Jacques; Tubiana, Roland; Lanternier, Fanny; Mamzer, Marie-France; Legendre, Christophe; Peyramond, Dominique; Caumes, Eric; Lortholary, Olivier; Buffet, Pierre

    2016-01-01

    We report on 4 patients (1 immunocompetent, 3 immunosuppressed) in whom visceral leishmaniasis had become unresponsive to (or had relapsed after) treatment with appropriate doses of liposomal amphotericin B. Under close follow-up, full courses of pentavalent antimony were administered without life-threatening adverse events and resulted in rapid and sustained clinical and parasitological cure.

  14. Discovery of palladium, antimony, tellurium, iodine, and xenon isotopes

    OpenAIRE

    Kathawa, J.; Fry, C; Thoennessen, M

    2012-01-01

    Currently, thirty-eight palladium, thirty-eight antimony, thirty-nine tellurium, thirty-eight iodine, and forty xenon isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  15. Effect of He+ irradiation on the optical properties of vacuum evaporated silver indium selenide thin films

    International Nuclear Information System (INIS)

    We prepared polycrystalline silver indium selenide thin films by vacuum evaporation on glass substrate at a high temperature using the stoichiometric powder. The samples were subjected to the irradiation of 1.26 M eV He+ ion. The effect of irradiation on the optical properties has been investigated for different fluencies of He+. The thin films were characterized by X-ray diffraction and UV-vis-NIR spectroscopy. It is observed that the band gap of silver indium selenide thin films decreases gradually from 1.17 to 0.82 eV with ion fluency.

  16. The determination of the thermodynamic activity of antimony in alpha-iron

    International Nuclear Information System (INIS)

    In this paper a method is suggested for determining the thermodynamic activity of antimony dissolved in alpha-iron, based on the study of antimony distribution between the two phases: liquid lead and solid iron. By this method, it was found that solid solutions of antimony in alpha-iron can be distinguished by positive divergences from the ideal state. Over a fairly wide range of concentrations, solutions of antimony in iron obey Henry's law. Special experiments on the distribution of antimony between lead and liquid iron showed that in the liquid state also the iron-antimony system is marked by positive divergences from the ideal state when small concentrations of antimony are present. The heat required for the solution of antimony in alpha-iron, and the excess partial molar entropy, were calculated from the activity temperature. The results were used for accurately locating the line showing the solubility limit of antimony in alpha-iron. Since alloys of antimony with iron were obtained by diffusion saturation and not by cooling from the liquid state, there was no liquefaction. Thus the lattice constant of the alloys and its relation to the alloy concentration could be reliably determined. The solubility limit established from X-ray data agrees with that obtained with Sb124. (author)

  17. The bulk modulus of cubic spinel selenides: an experimental and theoretical study

    DEFF Research Database (Denmark)

    Waskowska, A.; Gerward, Leif; Olsen, J.S.;

    2009-01-01

    It is argued that mainly the selenium sublattice determines the overall compressibility of the cubic spinel selenides, AB2Se4, and that the bulk modulus for these compounds is about 100GPa. The hypothesis is supported by experiments using high-pressure X-ray diffraction and synchrotron radiation,...

  18. Effect of sulfur doping on thermoelectric properties of tin selenide – A first principles study

    International Nuclear Information System (INIS)

    In this work we present the thermoelectric properties of tin selenide (SnSe) and sulfur doped tin selenide(SnSe(1-x)Sx, x= 0.125 and 0.25) obtained using first principles calculations. We investigated the electronic band structure using the FP-LAPW method within the sphere of the density functional theory. Thermoelectric properties were calculated using BOLTZTRAP code using the constant relaxation time approximation at three different temperatures 300, 600 and 800 K. Seebeck coefficient (S) was found to decrease with increasing temperature, electrical conductivity (σ/τ) was almost constant in the entire temperature range and thermal conductivity (κ/τ) increased with increasing temperature for all samples. Sulfur doped samples showed enhanced seebeck coefficient, decreased thermal conductivity and decreased electrical conductivity at all temperatures. At 300 K, S increased from 1500 µV/K(SnSe) to 1720μV/K(SnSe0.75S0.25), thermal conductivity decreased from 5 × 1015 W/mKs(SnSe) to 3 × 1015 W/mKs(SnSe0.75S0.25), electrical conductivity decreased from 7 × 1020/Ωms(SnSe) to 5 × 1020 /Ωms(SnSe0.75S0.25). These calculations show that sulfur doped tin selenide exhibit better thermoelectric properties than undoped tin selenide

  19. Benzyltrifluoromethyl (or Fluoroalkyl) Selenide: Reagent for Electrophilic Trifluoromethyl (or Fluoroalkyl) Selenolation.

    Science.gov (United States)

    Glenadel, Quentin; Ismalaj, Ermal; Billard, Thierry

    2016-09-16

    Trifluoromethylseleno substituent (CF3Se) is an emerging group, but its direct introduction onto organic molecules is still quite limited and mainly restricted to nucleophilic methods. Herein, we describe a new approach to easily and safely perform electrophilic trifluoromethylselenolation starting from a simple and easily accessible reagent, namely, benzyltrifluoromethyl selenide. This strategy can be generalized to various fluoroalkylselanyl groups, even functionalized ones. PMID:27571314

  20. Polystyrene-supported Selenides and Selenoxide:Versatile Routes to Synthesize Allylic Alcohols

    Institute of Scientific and Technical Information of China (English)

    Wei Ming XU; You Chu ZHANG; Xian HUANG

    2003-01-01

    Several polystyrene-supported selenides and selenoxide have been prepared firstly. These novel reagents were treated with LDA to produce selenium stabilized carbanions, which reacted with aldehydes and alkyl halides, followed by selenoxide syn-elimination and [2,3] sigmatropic rearrangement respectively to give Z-allylic alcohols stereoselectively.

  1. Synthesis and optical properties of cadmium selenide quantum dots for white light-emitting diode application

    International Nuclear Information System (INIS)

    Highlights: ► Stable CdSe QDs were synthesized by the one-step and two-level process respectively. ► The fabricated white LEDs show good white balance. ► CdSe QDs present well green to yellow band luminescence. ► CdSe QDs displayed a broad excitation band. - Abstract: Yellow light-emitting cadmium selenide quantum dots were synthesized using one-step and two-step methods in an aqueous medium. The structural luminescent properties of these quantum dots were investigated. The obtained cadmium selenide quantum dots displayed a broad excitation band suitable for blue or near-ultraviolet light-emitting diode applications. White light-emitting diodes were fabricated by coating the cadmium selenide samples onto a 460 nm-emitting indium gallium nitrite chip. Both samples exhibited good white balance. Under a 20 mA working current, the white light-emitting diode fabricated via the one-step and two-step methods showed Commission Internationale de l’Éclairage coordinates at (0.27, 0.23) and (0.27, 0.33), respectively, and a color rendering index equal to 41 and 37, respectively. The one-step approach was simpler, greener, and more effective than the two-step approach. The one-step approach can be enhanced by combining cadmium selenide quantum dots with proper phosphors

  2. 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

  3. Antimony and arsenic biogeochemistry in the western Atlantic Ocean

    Science.gov (United States)

    Cutter, Gregory A.; Cutter, Lynda S.; Featherstone, Alison M.; Lohrenz, Steven E.

    The subtropical to equatorial Atlantic Ocean provides a unique regime in which one can examine the biogeochemical cycles of antimony and arsenic. In particular, this region is strongly affected by inputs from the Amazon River and dust from North Africa at the surface, and horizontal transport at depth from high-latitude northern (e.g., North Atlantic Deep Water) and southern waters (e.g., Antarctic Bottom and Intermediate Waters). As a part of the 1996 Intergovernmental Oceanographic Commission's Contaminant Baseline Survey, data for dissolved As(III+V), As(III), mono- and dimethyl arsenic, Sb(III+V), Sb(III), and monomethyl antimony were obtained at six vertical profile stations and 44 sites along the 11,000 km transect from Montevideo, Uruguay, to Bridgetown, Barbados. The arsenic results were similar to those in other oceans, with moderate surface depletion, deep-water enrichment, a predominance of arsenate (>85% As(V)), and methylated arsenic species and As(III) in surface waters that are likely a result of phytoplankton conversions to mitigate arsenate "stress" (toxicity). Perhaps the most significant discovery in the arsenic results was the extremely low concentrations in the Amazon Plume (as low as 9.8 nmol/l) that appear to extend for considerable distances offshore in the equatorial region. The very low concentration of inorganic arsenic in the Amazon River (2.8 nmol/l; about half those in most rivers) is probably the result of intense iron oxyhydroxide scavenging. Dissolved antimony was also primarily in the pentavalent state (>95% antimonate), but Sb(III) and monomethyl antimony were only detected in surface waters and displayed no correlations with biotic tracers such as nutrients and chlorophyll a. Unlike As(III+V)'s nutrient-type vertical profiles, Sb(III+V) displayed surface maxima and decreased into the deep waters, exhibiting the behavior of a scavenged element with a strong atmospheric input. While surface water Sb had a slight correlation with

  4. 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

  5. Spray pyrolysis deposited tin selenide thin films for thermoelectric applications

    Energy Technology Data Exchange (ETDEWEB)

    Anwar, Sharmistha; Gowthamaraju, S.; Mishra, B.K.; Singh, S.K.; Shahid, Anwar, E-mail: shahidanwr@gmail.com

    2015-03-01

    Tin selenide thin films were prepared by spray pyrolysis technique using tin (II) chloride and selenourea as a precursor compounds using Se:Sn atomic ratio of 1:1 in the starting solution onto glass substrates. Deposition process was carried out in the substrate temperature range of 250 °C–400 °C using 1 ml/min flow rate. The films were investigated using X-ray diffraction, field emission scanning electron microscopy, Raman spectroscopy, optical absorption and thermoelectric studies. The X-ray diffraction patterns suggest that the major phase is hexagonal-SnSe{sub 2} was present when the deposition was carried out in 275–375 °C temperature range, while for the films deposited in the below and above to this range, Sn and Se precipitates into some impure and mixed phase. Raman scattering analysis allowed the assignment of peaks at ∼180 cm{sup −1} to the hexagonal-SnSe{sub 2} phase. The optical absorption study shows that the direct band gap of the film decreases with increase in substrate temperature and increasing crystallite size. The thermo-electrical measurements have shown n-type conductivity in as deposited films and the magnitude of thermo EMF for films has been found to be increasing with increasing deposition temperature, except for 350 °C sample. 350 °C deposited samples shows enhance thermoelectric value as compared to other samples. Thermoelectric study reveal that although sample deposited between 275 °C and 375 °C are structurally same but 350 °C sample is thermoelectrically best. - Highlights: • Influence of substrate temperature on the deposition of SnSe has been shown. • Seebeck measurements at 275°C–375 °C confirms n-type conductivity. • Higher seebeck coefficient has been observed at 350 °C deposited film. • Decrease in band gap was observed on increasing Tsub and size of the crystallites.

  6. States of antimony and tin atoms in lead chalcogenides

    International Nuclear Information System (INIS)

    It is shown by Mössbauer spectroscopy of the 119Sb(119mSn) isotope that impurity antimony atoms in PbS, PbSe, and PbTe lattices are distributed between cation and anion sublattices. In n-type samples, the greatest part of antimony is located in the anion sublattice; in hole ones, in the cation sublattice. The tin atoms formed as a result of radioactive decay of 119Sb (antisite state) are electrically inactive in the anion sub-lattice of PbS and PbSe, while, in the cation sublattice, they form donor U− centers. Electron exchange between the neutral and doubly ionized tin U− centers via the allowed band states is observed. The tin atoms formed after radioactive decay of 119Sb are electrically inactive in the anion and cation sublattices of PbTe.

  7. 无机锑系阻燃剂%Inorganic Antimony Series Fire Retardants

    Institute of Scientific and Technical Information of China (English)

    张亨

    2012-01-01

    无机锑系阻燃剂主要包括三氧化二锑、五氧化二锑溶胶和锑酸钠等。介绍了它们的性质、生产工艺、产品标准、阻燃用途和研发方向等。%Inorganic antimony series fire retardants include antimony trioxide, antimony pentoxide sol and sodium antimonate, etc. The properties, production process, production standard and uses of several inorganic antimony series fire retardants are introduced.

  8. Correlation of CsK{sub 2}Sb photocathode lifetime with antimony thickness

    Energy Technology Data Exchange (ETDEWEB)

    Mamun, M. A., E-mail: mmamu001@odu.edu; Elmustafa, A. A. [Department of Mechanical and Aerospace Engineering, Old Dominion University, Norfolk, Virginia 23529 (United States); The Applied Research Center, Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606 (United States); Hernandez-Garcia, C.; Poelker, M. [Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606 (United States)

    2015-06-01

    CsK{sub 2}Sb photocathodes with quantum efficiency on the order of 10% at 532 nm, and lifetime greater than 90 days at low voltage, were successfully manufactured via co-deposition of alkali species emanating from an effusion source. Photocathodes were characterized as a function of antimony layer thickness and alkali consumption, inside a vacuum chamber that was initially baked, but frequently vented without re-baking. Photocathode lifetime measured at low voltage is correlated with the antimony layer thickness. Photocathodes manufactured with comparatively thick antimony layers exhibited the best lifetime. We speculate that the antimony layer serves as a reservoir, or sponge, for the alkali.

  9. Correlation of CsK2Sb photocathode lifetime with antimony thickness

    Energy Technology Data Exchange (ETDEWEB)

    Mamun, M. A. [Department of Mechanical and Aerospace Engineering, Old Dominion University, Norfolk, Virginia 23529, USA; The Applied Research Center, Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA; Hernandez-Garcia, C. [Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA; Poelker, M. [Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA; Elmustafa, A. A. [Department of Mechanical and Aerospace Engineering, Old Dominion University, Norfolk, Virginia 23529, USA; The Applied Research Center, Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA

    2015-06-01

    CsK2Sb photocathodes with quantum efficiency on the order of 10% at 532 nm, and lifetime greater than 90 days at low voltage, were successfully manufactured via co-deposition of alkali species emanating from an effusion source. Photocathodes were characterized as a function of antimony layer thickness and alkali consumption, inside a vacuum chamber that was initially baked, but frequently vented without re-baking. Photocathode lifetime measured at low voltage is correlated with the antimony layer thickness. Photocathodes manufactured with comparatively thick antimony layers exhibited the best lifetime. We speculate that the antimony layer serves as a reservoir, or sponge, for the alkali.

  10. Correlation of CsK2Sb photocathode lifetime with antimony thickness

    Directory of Open Access Journals (Sweden)

    M. A. Mamun

    2015-06-01

    Full Text Available CsK2Sb photocathodes with quantum efficiency on the order of 10% at 532 nm, and lifetime greater than 90 days at low voltage, were successfully manufactured via co-deposition of alkali species emanating from an effusion source. Photocathodes were characterized as a function of antimony layer thickness and alkali consumption, inside a vacuum chamber that was initially baked, but frequently vented without re-baking. Photocathode lifetime measured at low voltage is correlated with the antimony layer thickness. Photocathodes manufactured with comparatively thick antimony layers exhibited the best lifetime. We speculate that the antimony layer serves as a reservoir, or sponge, for the alkali.

  11. Resistance to Arsenic- and Antimony-Based Drugs

    OpenAIRE

    Milena Salerno; Arlette Garnier-Suillerot

    2003-01-01

    Organic arsenicals were the first antimicrobial agents specifically synthesized for the treatment of infectious diseases such as syphilis and sleeping sickness. For the treatment of diseases caused by trypanosomatid parasites, organic derivatives of arsenic and the related metalloid antimony are still the drugs of choice. Arsenic trioxide, As203, has been used for a long time in traditional Chinese medicines for treatment of various diseases, and it has recently been shown to be clinically ac...

  12. Crystallization of antimony orthotantalate and its physical properties

    International Nuclear Information System (INIS)

    Physicochemical conditions of monophase synthesis of antimony orthoniobate monocrystals in the system SbO3-Ta2O5-KHF2-H2O2-H2O were investigated. In the area of monophase synthesis of SbTaO4 monocrystals kinetic studies of its growth conditions for inoculation, depending on solvent concentration, temperature, pyroelectric properties of the monocrystal grown were studied and conclusion was made on their practical use

  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. Recent advances on antimony(III/V) compounds with potential activity against tumor cells.

    Science.gov (United States)

    Hadjikakou, S K; Ozturk, I I; Banti, C N; Kourkoumelis, N; Hadjiliadis, N

    2015-12-01

    Antimony one of the heavier pnictogens, has been in medical use against microbes and parasites as well. Antimony-based drugs have been prescribed against leishmaniasis since the parasitic transmission of the tropical disease was understood in the beginning of the 20th century. The activity of arsenic against visceral leishmaniasis led to the synthesis of an array of arsenic-containing parasitic agents, among them the less toxic pentavalent antimonials: Stibosan, Neostibosan, and Ureastibamine. Other antimony drugs followed: sodium stibogluconate (Pentostam) and melglumine antimoniate (Glucantim or Glucantime); both continue to be in use today despite their toxic side effects and increasing loss in potency due to the growing resistance of the parasite against antimony. Antimony compounds and their therapeutic potentials are under consideration from many research groups, while a number of early reviews recording advances of antimony biomedical applications are also available. However, there are only few reports on the screening for antitumor potential of antimony compounds. This review focuses upon results obtained on the anti-proliferative activity of antimony compounds in the past years. This survey shows that antimony(III/V) complexes containing various types of ligands such as thiones, thiosemicarbazones, dithiocarbamates, carboxylic acids, or ketones, nitrogen donor ligands, exhibit selectivity against a variety of cancer cells. The role of the ligand type of the complex is elucidated within this review. The complexes and their biological activity are already reported elsewhere. However quantitative structure-activity relationship (QSAR) modeling studies have been carried out and they are reported for the first time here. PMID:26092367

  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. Tin dioxide sol-gel derived films doped with platinum and antimony deposited on porous silicon

    NARCIS (Netherlands)

    Savaniu, C.; Arnautu, A.; Cobianu, C.; Craciun, G.; Flueraru, C.; Zaharescu, M.; Parlog, C.; Paszti, F.; Berg, van den A.

    1999-01-01

    SnO2 sol-gel derived thin films doped simultaneously with Pt and Sb are obtained and reported for the first time. The Sn sources were tin(IV) ethoxide or tin(II) ethylhexanoate, while hexachloroplatinic acid (H2PtCl6) and antimony chloride (SbCl3) were used as platinum and antimony sources, respecti

  17. Oxidation and mobilization of metallic antimony in aqueous systems with simulated groundwater

    Science.gov (United States)

    Ilgen, A. G.; Majs, F.; Barker, A. J.; Douglas, T. A.; Trainor, T. P.

    2014-05-01

    Antimony (Sb) is a contaminant of concern that can be present in elevated concentrations in shooting range soils due to mobilization from spent lead/antimony bullets. Antimony in shooting range soils has been observed as either metallic Sb(0) or as Sb(V) immobilized by iron (hydr)oxides. The absence of Sb(III) in soils is indicative of rapid Sb(III) oxidation to Sb(V) under surface soil conditions. However, the major controls on antimony oxidation and mobility are poorly understood. To better understand these controls we performed multiple batch experiments under oxic conditions to quantify the oxidation and dissolution of antimony in systems where Sb(0) is oxidized to Sb(III) and further to Sb(V). We also tested how variations in the aqueous matrix composition and the presence of metallic lead (Pb) affect the dissolution, solid phase speciation, and oxidation of antimony. We monitored changes in the aqueous antimony speciation using liquid chromatography inductively coupled plasma mass spectrometry (LC-ICP-MS). To test which solid phases form as a result of Sb(0) oxidation, and therefore potentially limit the mobility of antimony in our studied systems, we characterized the partially oxidized Sb(0) powders by means of extended X-ray absorption fine structure (EXAFS) spectroscopy and powder X-ray diffraction (XRD).

  18. Leishmania donovani: an in vitro study of antimony-resistant amphotericin B-sensitive isolates

    DEFF Research Database (Denmark)

    Sharief, Abdalla Hassan; Gasim Khalil, Eltahir Awad; Theander, Thor G;

    2006-01-01

    Drug sensitivity of clinically antimony-unresponsive Leishmania donovani isolates from Eastern Sudan was evaluated in an in vitro culture system against sodium stibogluconate (Pentostam) and Amphotericin B. Eight isolates, six from antimony-resistant and two from clinically responsive patients were...

  19. Chemical synthesis of p-type nanocrystalline copper selenide thin films for heterojunction solar cells

    International Nuclear Information System (INIS)

    Nanocrystalline thin films of copper selenide have been grown on glass and tin doped-indium oxide substrates using chemical method. At ambient temperature, golden films have been synthesized and annealed at 200 deg. C for 1 h and were examined for their structural, surface morphological and optical properties by means of X-ray diffraction (XRD), scanning electron microscopy and UV-vis spectrophotometry techniques, respectively. Cu2-xSe phase was confirmed by XRD pattern and spherical grains of 30 ± 4 - 40 ± 4 nm in size aggregated over about 130 ± 10 nm islands were seen by SEM images. Effect of annealing on crystallinity improvement, band edge shift and photoelectrochemical performance (under 80 mW/cm2 light intensity and in lithium iodide electrolyte) has been studied and reported. Observed p-type electrical conductivity in copper selenide thin films make it a suitable candidate for heterojunction solar cells

  20. Chemical synthesis of p-type nanocrystalline copper selenide thin films for heterojunction solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Ambade, Swapnil B. [Department of Chemical Engineering, Vishwakarma Institute of Technology, Pune 411037 (India); Mane, R.S. [Inorganic Nanomaterials Laboratory, Department of Chemistry, Hanyang University, Sungdong-Ku, Haengdang-dong 17, Seoul 133-791 (Korea, Republic of); Kale, S.S. [Inorganic Nanomaterials Laboratory, Department of Chemistry, Hanyang University, Sungdong-Ku, Haengdang-dong 17, Seoul 133-791 (Korea, Republic of); Sonawane, S.H. [Department of Chemical Engineering, Vishwakarma Institute of Technology, Pune 411037 (India); Shaikh, Arif V. [Department of Electronic Science, AKI' s Poona College of Arts, Science and Commerce, Camp, Pune 411 001 (India); Han, Sung-Hwan [Inorganic Nanomaterials Laboratory, Department of Chemistry, Hanyang University, Sungdong-Ku, Haengdang-dong 17, Seoul 133-791 (Korea, Republic of)]. E-mail: shhan@hanyang.ac.kr

    2006-12-15

    Nanocrystalline thin films of copper selenide have been grown on glass and tin doped-indium oxide substrates using chemical method. At ambient temperature, golden films have been synthesized and annealed at 200 deg. C for 1 h and were examined for their structural, surface morphological and optical properties by means of X-ray diffraction (XRD), scanning electron microscopy and UV-vis spectrophotometry techniques, respectively. Cu{sub 2-x}Se phase was confirmed by XRD pattern and spherical grains of 30 {+-} 4 - 40 {+-} 4 nm in size aggregated over about 130 {+-} 10 nm islands were seen by SEM images. Effect of annealing on crystallinity improvement, band edge shift and photoelectrochemical performance (under 80 mW/cm{sup 2} light intensity and in lithium iodide electrolyte) has been studied and reported. Observed p-type electrical conductivity in copper selenide thin films make it a suitable candidate for heterojunction solar cells.

  1. Cytocompatibility of direct water synthesized cadmium selenide quantum dots in colo-205 cells

    OpenAIRE

    Rodriguez-Torres, Marcos R.; Velez, Christian; Zayas, Beatriz; Rivera, Osvaldo; Arslan, Zikri; Gonzalez-Vega, Maxine N.; Diaz-Diestra, Daysi; Beltran-Huarac, Juan; Morell, Gerardo; Primera-Pedrozo, Oliva M.

    2015-01-01

    Cadmium selenide quantum dots (CdSe QDs), inorganic semiconducting nanocrystals, are alluring increased attraction due to their highly refined chemistry, availability, and super tunable optical properties suitable for many applications in different research areas, such as photovoltaics, light-emitting devices, environmental sciences, and nanomedicine. Specifically, they are being widely used in bio-imaging in contrast to organic dyes due to their high brightness and improved photo-stability, ...

  2. Research on Percolation Network and Physical Properties of Graphite/Antimony Composites

    Institute of Scientific and Technical Information of China (English)

    HU Ya-fei; HE Min; WANG Qi-li

    2006-01-01

    The microstructure, friction and wear behaviour of graphite preform and graphite/antimony composites are analysed based on the percolation theory of hydrodynamics to investigate the relationship between the percolation network and physical properties of graphite/antimony composites. The result shows that there are two important factors to enhance friction and wear behaviour of graphite/antimony composites at high temperature: 1) the formation of the pore network in the preform, which is called the first percolation and 2) the optimization of infiltration method in the process of infiltrating antimony, which is called the second percolation. By adding some pyrolysate and controlling the roasting process, perfect net pores and sub-micron percolation microstructure may be formed in the graphite preform. By controlling the infiltration process, the saturation of molten antimony infiltrating into perfect pores can be optimized.

  3. Theory of two-magnon Raman scattering in alkaline iron selenide superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Liu, C.S. [Department of Physics, Yanshan University, Qinhuangdao 006004 (China); Department of Physics, National Taiwan Normal University, Taipei 11677, Taiwan (China); Zhang, A.M. [Department of Physics, Renmin University of China, Beijing 100872 (China); Xu, T.F. [Department of Physics, Yanshan University, Qinhuangdao 006004 (China); Wu, W.C., E-mail: wu@phy.ntnu.edu.tw [Department of Physics, National Taiwan Normal University, Taipei 11677, Taiwan (China)

    2014-11-15

    Highlights: • Two-magnon Raman scattering is theoretically studied for alkaline iron selenides. • Underlying spin interactions of the √(5)×√(5) AF superstructure are investigated in details. • Optimal set of exchange parameters is revealed when fitting to experiments. - Abstract: Motivated by the recent experiment of two-magnon Raman scattering in alkaline iron selenide superconductors (Zhang et al., 2012), we investigate in details the underlying spin interactions of the √(5)×√(5) antiferromagnetic superstructure. Based on the linear spin wave approximation, the Fleury-London (FL) two-magnon Raman cross-sections are calculated. By comparing theoretical results with the Raman data in both A{sub g} and B{sub g} channels, an optimal set of exchange parameters which are consistent with the fitting to the neutron scattering data are obtained. It reveals that the experimentally observed broad and asymmetric peaks around 1600 cm{sup −1} are dominantly originated from quasiparticle excitations in two nearly degenerate magnon bands in the (0,±π) and (±π,0) directions. The result thus supports that the magnetic properties in alkaline iron selenide AFe{sub 1.6+x}Se{sub 6} superconductors can be basically described by the quantum spin model with up to third nearest-neighbor exchange couplings.

  4. Lattice Dynamics at Zone-Center of Sulphide and Selenide Spinels

    Institute of Scientific and Technical Information of China (English)

    A.K. Kushwaha

    2008-01-01

    A rigid-ion model is used to calculate the force constants and effective dynamical charges of sulphide and selenide spinels. The Raman and infrared phonon modes of normal cubic sulphide spinels MCr2S4 (M=Mn, Co, Fe, Hg, Zn, and Cd) and selenide spinels MCr2Se4 (M=Hg, Zn, and Cd) are calculated at the first Brillouin zone-centre using above model. The significant outcome of the present work is (I) the interatomic interaction between Cr-S (Se) dominates over the Cr-S(Se) and S-S(Se-Se) type of interatomic interactions, (ii) the effective dynamical charges of the bivalent metal ions are nearly zero, and (ⅲ) the selenide spinels are less ionic than the sulphide spinels and the ionicity decreases as MnCr2S4 FeCr2S4 CoCr2S4 > and CdCr2C4 > ZnCr2C4 > HgCr2C4 (C=S and Se). The zone-center phonon frequencies, calculated using these parameters, are found to be in very good agreement with the observed results.

  5. Testing of antimony selective media for treatment of liquid radwaste

    International Nuclear Information System (INIS)

    Nuclear power plants have sought radiation source term reduction and reduced discharge of radioactive constituents for many years. In the case of pressurized water reactors (PWRs), the latter efforts have been directed toward capture and immobilization of recalcitrant (ubiquitous radionuclides with long half-lives) species such as Cs-134 and Cs-137 and Co-58 and Co-60. As these plants resolved, or at least mitigated, the problems with radiocesium and radio-cobalt, antimony radionuclides (Sb-122, Sb-124, and Sb-125) have become a primary concern in liquid liquid radwaste systems Graver Technologies developed a granular composite metal oxide media with good selectivity for radio-antimony. Initial laboratory data were collected using non-radioactive salts of antimony, cesium, and cobalt to judge efficacy of selective removal of antimony. Based on success of those trials, the media, designated Gravex GX187, was tested in partnership with Energy Solutions (nee Duratek) using actual liquid liquid radwaste in two PWR plants. One of these plants performed extensive slip-stream trials comparing the GX187 with strong base anion resins. With more than 2500 bed volumes of throughput, the GX187 outperformed the other competitors by reducing both Sb-124 and Sb-125 radionuclides below minimum detectable activity (MDA) with average decontamination factors (DF's) of 170, even when subjected to high levels of borate. Based on these favorable results, Energy Solutions installed the GX187 in a layered bed in their ALPS liquid radwaste processing system at this plant in August 2005. After one year of intermittent, batchwise operation including an outage, the GX187 processed more than 2.25 million liters (>600,000 gallons) of liquid liquid radwaste while reducing the Sb-125 activity to 2.9 E-08 Bq/L (DF=111) on average. This evaluation is ongoing and will continue at least until the fall 2006 outage at this plant. Concurrently, Graver developed a second generation antimony selective

  6. Behavior of ruthenium, cesium and antimony during simulated HLLW vitrification

    International Nuclear Information System (INIS)

    The behavior of ruthenium, cesium, and antimony during the vitrification of simulated high-level radioactive liquid wastes (HLLW) in a liquid fed melter was studied on a laboratory scale and on a semi-pilot scale. In the laboratory melter of a 2.5 kg capacity, a series of tests with the simulate traced with 103Ru, 134Cs and 124Sb, has shown that the Ru and Cs losses to the melter effluent are generally higher than 10% whereas the antimony losses remain lower than 0.4%. A wet purification system comprising in series, a dust scrubber, a condenser, an ejector venturi and an NOx washing column retains most of the activity present in the off-gas so that the release fractions for Ru at the absolute filter inlet ranges between 5.10-3 to 5.10-5% of the Ru fed, for Cs the corresponding release fraction ranges between 3.10-3 to 10-4% and for Sb the release fraction ranges between 1.7 10-4 to 1.7 10-5%. The same experiments were performed at a throughput of 1 to 2 1 h-1 of simulated solution in the semi-pilot scale unit RUFUS. The RUFUS unit comprises a glass melter with a 50 kg molten glass capacity and the wet purification train comprises in series a dust scrubber, a condenser, an ejector venturi and an NOx washing column. The tracer tests were restricted to 103Ru and 134Cs since the laboratory tests had shown that the antimony losses were very low. The results of the tests are presented

  7. 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

  8. 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.

  9. Antimony implanted strained Si for nMOSFET applications

    OpenAIRE

    Zamani, Atieh

    2009-01-01

    Incorporation of implanted antimony (Sb) in strained-silicon (s-Si) formed on relaxed-SiGe virtual substrates (10 and 30% Ge) has been studied. The implantation doses were 5×1013- 5×1014 cm-2 with an energy of 20 keV. The activation of dopant was performed by an rapid thermal annealing (RTA) treatment at 700 and 800 °C for 30 sec. Projected range of this implantation is about 20 nm which was also confirmed by different techniques. The layers were analyzed in terms of strain relaxation, sheet ...

  10. Solubility behaviour of antimony(III) and antimony(V) solids in basic aqueous solutions at 300{sup o}C

    Energy Technology Data Exchange (ETDEWEB)

    Lemire, R.J.; Tosello, N.B.; Halliday, J.D

    1999-12-01

    The major contributions of the isotopes {sup 122}Sb and {sup 124}Sb to activity transport in a CANDU reactor primary heat transport system (HTS), have been associated with oxygen ingress during reactor shutdown. As part of a program to minimize the release and redeposition of these isotopes, the solubilities of antimony(III) and (V) oxides and salts have been measured in basic solutions at temperatures from 25 to 300{sup o}C. The results provide information on the charge and the stability as a function of temperature of antimony solution species and, hence, a guide to the trends in the temperature dependence of the solubilities of antimony solids. In solutions in which oxidation of antimony(III) to antimony(V) is minimized, the solubility of Sb{sub 2}O{sub 3} increases by about two orders of magnitude between 25 and 200{sup o}C, and then levels out or decreases slightly. At 250{sup o}C, in oxidizing solutions, Sb{sub 2}O{sub 5}{center_dot}xH{sub 2}O and simple sodium antimonate(V) were found to be unstable in sodium hydroxide solutions with respect to the solid, Na{sub 2{alpha}}[H(H{sub 2}O)]{sub 2-2{alpha}}Sb{sub 2}O{sub 6}, which has a pyrochlore structure. The solubility of this partially protonated sodium antimonate increases from 25 to 200{sup o}C and decreases at temperatures above 250{sup o}C. These solubility changes for the antimony (V) solids reflect changes in the stability of the anionic antimony solution species (SbO{sub 3}{sup -} or Sb(OH){sub 6}{sup -}), even though the compositions of antimony-containing solids in basic oxidizing solutions are strongly dependent on the cations and their aqueous phase concentrations. All solids used in the present experiments would be expected to generate total solution antimony concentrations {>=} 0.00005 mol{center_dot}dm{sup -3} in any neutral or basic aqueous solutions (assuming no added sodium salts). Therefore, under HTS conditions, precipitation of any antimony oxides or mixed oxides is unlikely. It cannot be

  11. Antimony removal from the polyethylene terephthalate manufacture wastewater

    Directory of Open Access Journals (Sweden)

    Tomas Vengris

    2010-04-01

    Full Text Available In this study, antimony removal by coagulation from polyethylene terephthalate resin production wastewater of „Orion Global PET“ factory in Klaipėda city was investigated, with regard to the dependence of coagulant type and dosage, pH and presence of organics. FeCl3 ∙6H2O, FeSO4 ∙7H2O, AlCl3∙6H2O and TiCl4 salts were used as coagulants. Ti(IV and Fe(III revealed oneself to be the most effective coagulants. Antimony removal effectiveness is moderate and low using FeSO4 ∙7H2O and AlCl3∙6H2O coagulants, respectively. The addition of 10 mg dm-3 Ti(IV and 30 mg dm-3 Fe(III reduces by ~98% of the Sb, when the initial amount of Sb in wastewater is about 1200 mkg/l. The action of Fe(III is practically independent in the pH range 4-9, and that of Ti(IV slightly decreases in the same pH interval. The Sb amount in wastewater can be reduced to 13-20 mkg dm-3, while the initial Sb concentration is 1200 mkg dm-3. The presence of organic compounds in wastewater determines the reduction of Sb removal by coagulation.

  12. Alkali oxide-tantalum, niobium and antimony oxide ionic conductors

    Science.gov (United States)

    Roth, R. S.; Brower, W. S.; Parker, H. S.; Minor, D. B.; Waring, J. L.

    1975-01-01

    The phase equilibrium relations of four systems were investigated in detail. These consisted of sodium and potassium antimonates with antimony oxide and tantalum and niobium oxide with rubidium oxide as far as the ratio 4Rb2O:llB2O5 (B=Nb, Ta). The ternary system NaSbO3-Sb2O4-NaF was investigated extensively to determine the actual composition of the body centered cubic sodium antimonate. Various other binary and ternary oxide systems involving alkali oxides were examined in lesser detail. The phases synthesized were screened by ion exchange methods to determine mobility of the mobility of the alkali ion within the niobium, tantalum or antimony oxide (fluoride) structural framework. Five structure types warranted further investigation; these structure types are (1) hexagonal tungsten bronze (HTB), (2) pyrochlore, (3) the hybrid HTB-pyrochlore hexagonal ordered phases, (4) body centered cubic antimonates and (5) 2K2O:3Nb2O5. Although all of these phases exhibit good ion exchange properties only the pyrochlore was prepared with Na(+) ions as an equilibrium phase and as a low porosity ceramic. Sb(+3) in the channel interferes with ionic conductivity in this case, although relatively good ionic conductivity was found for the metastable Na(+) ion exchanged analogs of RbTa2O5F and KTaWO6 pyrochlore phases.

  13. Antimony contamination and its effect on Trifolium plants

    Science.gov (United States)

    Corrales, Isabel; Barceló, Juan; Bech, Jaume; Poschenrieder, Charlotte

    2014-05-01

    Antimony is not an essential element and soil Sb contents usually are low.However, soil contamination by Sb has increased in the last years due to the human activities (combustion of fossil fuels, mining, waste incineration, smelting, shooting and road traffic). The main objective of this work was to study the effect of different concentrations of antimony (KSb(OH)6) in order to evaluate the effect on growth and Sb uptake on Trifolium pratense cv. Milvus and Trifolium repens. Our results show that Sb accumulated both in roots and shoots of clover without any negative effect on root growth, cellular viability and lipid peroxidation. This absence of toxicity sympthoms in clover plants could be very dangerous because Sb can be inadvertedly incorporated into the trophic chain causing toxic effects both in animals and humans. The absence of toxic effects on plants does not seem to be due to detoxification by phytochelatins because the use of the gamma-glutamylcysteine synthetase inhibitor, L-buthionine-[S,R]-sulphoximine (BSO) did not enhance Sb toxicity to plants. (Supported by the Spanish MICINN project BFU2010-14873)

  14. Thermal decomposition kinetics of antimony oxychloride in air

    Institute of Scientific and Technical Information of China (English)

    阳卫军; 唐谟堂; 金胜明

    2002-01-01

    The DTA and XRD techniques were employed to study thermal decomposition mechanism of antimony oxychloride SbOCl in the air. The thermal decomposition reaction occurs in four steps, and the former three steps as: SbOCl(s)→Sb4O5Cl2(s)+SbCl3(g)→Sb8O11Cl2(s)+SbCl3(g)→Sb2O3(s)+SbCl3(g). The forth step is the oxidation of Sb2O3 by air, Sb2O3(s)+O2→Sb2O4(s). The activation energy and the order of the thermal decomposition reaction of antimony oxychloride in three steps presented in DTA curves were calculated according to Kinssinger methods from DTA curves. The values of activation energy and the order are respectively 91.97kJ/mol, 0.73 in the first step, 131.14kJ/mol, 0.63 in the second step and 146.94kJ/mol, 1.58 in the third step.

  15. BSA activated CdTe quantum dot nanosensor for antimony ion detection.

    Science.gov (United States)

    Ge, Shenguang; Zhang, Congcong; Zhu, Yuanna; Yu, Jinghua; Zhang, Shuangshuang

    2010-01-01

    A novel fluorescent nanosensor for Sb(3+) determination was reported based on thioglycolic acid (TGA)-capped CdTe quantum dot (QD) nanoparticles. It was the first antimony ion sensor using QD nanoparticles in a receptor-fluorophore system. The water-soluable TGA-capped CdTe QDs were prepared through a hydrothermal route, NaHTe was used as the Te precursor for CdTe QDs synthesis. Bovine serum albumin (BSA) conjugated to TGA-capped CdTe via an amide link interacting with carboxyl of the TGA-capped CdTe. When antimony ion enters the BSA, the lone pair electrons of the nitrogen and oxygen atom become involved in the coordination, switching off the QD emission and a dramatic quenching of the fluorescence intensity results, allowing the detection of low concentrations of antimony ions. Using the operating principle, the antimony ion sensor based on QD nanoparticles showed a very good linearity in the range 0.10-22.0 microg L(-1), with the detection limit lower than 2.94 x 10(-8) g L(-1) and the relative standard deviation (RSD) 2.54% (n = 6). In a study of interferences, the antimony-sensitive TGA-QD-BSA sensor showed good selectivity. Therefore, a simple, fast, sensitive, and highly selective assay for antimony has been built. The presented method has been applied successfully to the determination of antimony in real water samples (n = 6) with satisfactory results.

  16. Removal of cobalt from zinc sulphate solution using rude antimony trioxide as additive

    Institute of Scientific and Technical Information of China (English)

    戴军; 王德全; 姜澜; 金曼

    2002-01-01

    The process of cobalt removal from zinc sulphate solution using rude antimony trioxide as an additive was investigated. The rude antimony trioxide was produced in treatment of copper and lead anode mud and its main components are antimony trioxide, antimony arsenate and lead antimonate. Using the rude antimony trioxide as the additive of cobalt removal can not only decrease operation cost of purification but also find out a new way for utilization of the rude antimony trioxide. The effects of temperature, dosage of zinc dust, the rude antimony trioxide, copper ion and solution pH on removal of cobalt were studied. And experimental data using the rude Sb2O3 as additive were compared with those using Sb2O3. The results indicate that using rude Sb2O3 as additive, cobalt concentration in solution could be decreased from 24mg/L to below 1mg/L under about the same conditions as using Sb2O3.

  17. Leaching Mechanism of Complicated Antimony-Lead Concentrate and Sulfur Formation in Slurry Electrolysis

    Institute of Scientific and Technical Information of China (English)

    WangChengyan; QiuDingfan; JiangPeihai

    2004-01-01

    Anodic reaction mechanism of complicated antimony-lead concentrate in slurry electrolysis was investigated by the anodic polarization curves determined under various conditions. The main reactions on the anode are the oxidations of FeCln(2-n) . Though the oxidation of jamesonite particle on the anode can occur during the whole process, it is less. With the help of mineralogy studies and relevant tests, the leaching reaction mechanism of jameson[to and gudmundite during slurry electrolysis was ascertained. Because of the oxidation reaction of FeCl3 produced by antimony-lead concentrate itself, the non-oxidation complex acid dissolution of jameson[re, the oxidation complex acid dissolution of gudmundite, and the oxidation of air carried by stirring, the leaching ratio of antimony reaches about 35% when HCl-NH4Cl solution is used to leach antimony-lead concentrate directly. So when the theoretical electric quantity is given to oxidation of antimony in slurry electrolysis, all of antimony, lead and iron containing in antimony-lead concentrate, are leached. The formation of sulfur is through the directly redox reaction of Fe3+ and jameson[re. The S2- in jamesonite is oxidized into S0 , and forms the crystals of sulfur again on the spot. The redox reaction of Fe3+ and H2S formed by non-oxidative acid dissolution of jamesonite is less.

  18. 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.

  19. 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

  20. 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.

  1. Structural and optical characterization of thermally evaporated bismuth and antimony films for photovoltaic applications

    Science.gov (United States)

    Srimathy, N.; Ruban Kumar, A.

    2016-05-01

    In this present study, the thin film of bismuth and antimony is coated by thermal evaporation system equipped with the inbuilt ultra high vacuum system. XRD analysis confirmed the rhombohedral structure of Bismuth and Antimony on the prepared film. The surface roughness and physical appearance is analyzed by Atomic force microscopy. The results of Raman Spectroscopy show the wave functions and the spectrum of electrons. The preparation technique and conditions strongly influence the crystalline structure and the phase composition of bismuth and antimony thin films. The electrical and optical properties for the prepared film are analyzed. The results show a great interest and promising applications in Photovoltaic devices.

  2. Coordination- and Redox-Noninnocent Behavior of Ambiphilic Ligands Containing Antimony.

    Science.gov (United States)

    Jones, J Stuart; Gabbaï, François P

    2016-05-17

    Stimulated by applications in catalysis, the chemistry of ambiphilic ligands featuring both donor and acceptor functionalities has experienced substantial growth in the past several years. The unique opportunities in catalysis offered by ambiphilic ligands stem from the ability of their acceptor functionalities to play key roles via metal-ligand cooperation or modulation of the reactivity of the metal center. Ligands featuring group 13 centers, most notably boranes, as their acceptor functionalities have undoubtedly spearheaded these developments, with remarkable results having been achieved in catalytic hydrogenation and hydrosilylation. Motivated by these developments as well as by our fundamental interest in the chemistry of heavy group 15 elements, we became fascinated by the possibility of employing antimony centers as Lewis acids within ambiphilic ligands. The chemistry of antimony-based ligands, most often encountered as trivalent stibines, has historically been considered to mirror that of their lighter phosphorus-based congeners. There is growing evidence, however, that antimony-based ligands may display unique coordination behavior and reactivity. Additionally, despite the diverse Lewis acid and redox chemistry that antimony exhibits, there have been only limited efforts to explore this chemistry within the coordination sphere of a transition metal. By incorporation of antimony into the framework of polydentate ligands in order to enforce the main group metal-transition metal interaction, the effect of redox and coordination events at the antimony center on the structure, electronics, and reactivity of the metal complex may be investigated. This Account describes our group's continuing efforts to probe the coordination behavior, reactivity, and application of ambiphilic ligands incorporating antimony centers. Structural and theoretical studies have established that both Sb(III) and Sb(V) centers in polydentate ligands may act as Z-type ligands toward late

  3. Coordination- and Redox-Noninnocent Behavior of Ambiphilic Ligands Containing Antimony.

    Science.gov (United States)

    Jones, J Stuart; Gabbaï, François P

    2016-05-17

    Stimulated by applications in catalysis, the chemistry of ambiphilic ligands featuring both donor and acceptor functionalities has experienced substantial growth in the past several years. The unique opportunities in catalysis offered by ambiphilic ligands stem from the ability of their acceptor functionalities to play key roles via metal-ligand cooperation or modulation of the reactivity of the metal center. Ligands featuring group 13 centers, most notably boranes, as their acceptor functionalities have undoubtedly spearheaded these developments, with remarkable results having been achieved in catalytic hydrogenation and hydrosilylation. Motivated by these developments as well as by our fundamental interest in the chemistry of heavy group 15 elements, we became fascinated by the possibility of employing antimony centers as Lewis acids within ambiphilic ligands. The chemistry of antimony-based ligands, most often encountered as trivalent stibines, has historically been considered to mirror that of their lighter phosphorus-based congeners. There is growing evidence, however, that antimony-based ligands may display unique coordination behavior and reactivity. Additionally, despite the diverse Lewis acid and redox chemistry that antimony exhibits, there have been only limited efforts to explore this chemistry within the coordination sphere of a transition metal. By incorporation of antimony into the framework of polydentate ligands in order to enforce the main group metal-transition metal interaction, the effect of redox and coordination events at the antimony center on the structure, electronics, and reactivity of the metal complex may be investigated. This Account describes our group's continuing efforts to probe the coordination behavior, reactivity, and application of ambiphilic ligands incorporating antimony centers. Structural and theoretical studies have established that both Sb(III) and Sb(V) centers in polydentate ligands may act as Z-type ligands toward late

  4. Synthesis and characterisation of nano-pore antimony imprinted polymer and its use in the extraction and determination of antimony in water and fruit juice samples.

    Science.gov (United States)

    Shakerian, Farid; Dadfarnia, Shayessteh; Haji Shabani, Ali Mohammad; Nili Ahmad Abadi, Maryam

    2014-02-15

    A solid phase extraction method using antimony ion imprinted polymer (IIP) sorbent combined with electrothermal atomic absorption spectrometry (ETAAS) was developed for the extraction and speciation of antimony. The sorbent has been synthesised in the presence of Sb(III) and ammonium pyrrolidine dithiocarbamate (APDC) using styrene as the monomer and ethylene glycol dimethacrylate (EGDMA) as the cross linker. The imprinted Sb(III) ions were removed by leaching with HCl (50%v/v) and the polymer was characterised by FT-IR and scanning electron microscopy. The maximum sorption capacity of the IIP for Sb(III) ions was found to be 6.7 mg g(-1). With preconcentration of 60 mL of sample, an enhancement factor of 232 and detection limit of 3.9 ng L(-1) was obtained. Total antimony was determined after the reduction of Sb(V) to Sb(III). The method was successfully applied to the determination of antimony species in water samples and total antimony in fruit juices.

  5. Anthropogenic impacts on the biogeochemistry and cycling of antimony.

    Science.gov (United States)

    Shotyk, William; Krachler, Michael; Chen, Bin

    2005-01-01

    Antimony is a potentially toxic trace element with no known biological function. Antimony is commonly enriched in coals, and fossil fuel combustion appears to be the largest single source of anthropogenic Sb to the global atmosphere. Abundant in sulfide minerals, its emission to the atmosphere from anthropogenic activities is linked to the mining and metallurgy of non-ferrous metals, especially Pb, Cu, and Zn. In particular, the geochemical and mineralogical association of Sb with Pb minerals implies that, like Pb, Sb has been emitted to the environment for thousands of years because of Pb mining, smelting, and refining. In the US alone, there are more than 400 former secondary lead smelting operations and worldwide there are 133 Pb-Zn smelters in operation today. Antimony is used in creating and improving dozens of industrial and commercial materials including various alloys, ceramics, glasses, plastics, and synthetic fabrics, making waste incineration another important source of Sb to the environment. Enrichments of Sb in atmospheric aerosols, plants, soils, sediments, as well as alpine and polar snow and ice suggest that Sb contamination is extensive, but there are very few quantitative studies of the geographic extent, intensity, and chronology of this contamination. There is an urgent need to quantify the extent of human impacts and how these have changed with time. The decreasing inventories of anthropogenic Sb with time in peat cores from Switzerland and Scotland suggest that the atmospheric Sb flux may be declining, but there have been too few studies to make any general conclusions. In fact, some studies of sediments and biomonitors in central Europe show little decline in Sb concentrations during the past decades. There is an obvious need for reliable data from well dated archives such as polar snow and ice, peat bogs, and sediments. The air concentrations, extent of enrichment, particle size distribution, and rate of deposition of Sb in urban areas is

  6. Biogeochemistry of Antimony(V) in Microcosms under Sulfidogenic Conditions

    Science.gov (United States)

    O'Loughlin, E. J.; Johnson, C. R.; Antonopoulos, D. A.; Boyanov, M.; Flynn, T. M.; Koval, J. C.; Kemner, K. M.

    2015-12-01

    As the mining and use of antimony continues to increase, environmental concerns involving the element have grown. Antimony(V) and (III) are the two most environmentally-relevant oxidation states, but little is known about the redox transitions between the two in natural systems. To better understand the behavior of antimony in anoxic environments, we examined the transformations of Sb(V) under Fe(III)- and sulfate-reducing conditions in aqueous suspensions that contained 2 mM KSb(OH)6, 50 mM Fe(III) (as ferrihydrite), 10 mM sulfate, and 10 mM lactate, and were inoculated with sediment from a wetland on the campus of Argonne National Laboratory in Argonne, Illinois. Samples were collected over time to track changes in the concentrations of Sb, Fe(II), sulfate, and lactate, as well as the composition of the microbial community as determined by 16S rRNA gene inventories. We also examined the interaction of Sb(V) with pure Fe(II) mineral phases in aqueous suspensions containing 2 mM KSb(OH)6 and 50 mM Fe(II) as either magnetite, sideritre, vivianite, green rust, or mackinawite. X-ray absorption fine-structure spectroscopy was used to determine the valence state of Sb and its chemical speciation. Lactate was rapidly fermented to acetate and propionate concomittant with a bloom of Veillonellaceae. Utilization of propionate for dissimilatory sulfate reduction (DSR) was accompanied by an increase in Desulfobulbaceae. Sb K-edge X-Ray absorption near edge structure (XANES) analysis showed reduction of Sb(V) to Sb(III) within 4 weeks, concurrent with DSR and the formation of FeS. We observed variable responses in the ability of specific Fe(II) minerals to reduce Sb(V). No reduction was observed with magnetite, siderite, vivianite, or green rust. In the presence of mackinawite (FeS), however, Sb(V) was reduced to Sb(III) sulfide. These results suggest that the reduction of Sb(V) to Sb(III) is not likely under solely Fe(III)-reducing conditions, but is expected in sulfidogenic

  7. Influence of the chromium and ytterbium co-doping on the photoluminescence of zinc selenide crystals

    Institute of Scientific and Technical Information of China (English)

    I Radevici

    2014-01-01

    The luminescent properties of ZnSe, ZnSe:Cr (0.05 at.%Cr), ZnSe:Yb (0.03 at.%Yb) and ZnSe:Cr:Yb (0.05 at.%Cr, 0.05 at.%Yb) crystals, doped during the growth process by the chemical vapor transport method, were studied within the temperature in-terval of 6-300 K. At the 6 K temperature in the visible spectral range 2 bands were observed:a band in the excitonic spectral region and a band of self-activated luminescence. It was shown that co-doping of zinc selenide crystals with the chromium and ytterbium led to the combination of the impurities influence on the photoluminescent properties. At the liquid helium temperature in the middle in-frared range of the spectra of the ytterbium and chromium co-doped crystal a band with the maximum localized at 1.7 µm was ob-served, which was overlapped with a complex band in the middle-IR spectral range, characteristic for the chromium doped ZnSe crys-tals. On the basis of obtained data an interaction mechanism of the chromium and ytterbium co-doping impurities was proposed. Guided by the existent model of the ytterbium ion incorporation in the selenide sublattice of the ZnSe crystals, an assumption about stabilization of single charged chromium ions in the zinc sublattice crystal nodes, by means of formation of the local charge compen-sating clusters, was made. It was assumed that the resonant energy transfer from one chromium ion to another, which led to the con-centration quenching of the IR emission in the ZnSe:Cr PL spectra, would lead to the broadening of the IR emission in the spectra of ytterbium and chromium co-doped zinc selenide crystals.

  8. Selenide and telluride glasses for mid-infrared bio-sensing

    Science.gov (United States)

    Cui, Shuo; Chahal, Radwan; Shpotyuk, Yaroslav; Boussard, Catherine; Lucas, Jacques; Charpentier, Frederic; Tariel, Hugues; Loréal, Olivier; Nazabal, Virginie; Sire, Olivier; Monbet, Valérie; Yang, Zhiyong; Lucas, Pierre; Bureau, Bruno

    2014-02-01

    Fiber Evanescent Wave Spectroscopy (FEWS) is an efficient way to collect optical spectra in situ, in real time and even, hopefully, in vivo. Thanks to selenide glass fibers, it is possible to get such spectra over the whole mid-infrared range from 2 to 12 μm. This working window gives access to the fundamental vibration band of most of biological molecules. Moreover selenide glasses are stable and easy to handle, and it is possible to shape the fiber and create a tapered sensing head to drastically increase the sensitivity. Within the past decades, numerous multi-disciplinary studies have been conducted in collaboration with the City Hospital of Rennes. Clinical trials have provided very promising results in biology and medicine which have led to the creation in 2011 of the DIAFIR Company dedicated to the commercialization of fiber-based infrared biosensors. In addition, new glasses based on tellurium only have been recently developed, initially in the framework of the Darwin mission led by the European Space Agency (ESA). These glasses transmit light further into the far-infrared and could also be very useful for medical applications in the near future. Indeed, they permit to reach the vibrational bands of biomolecules laying from 12 to 16 μm where selenide glasses do not transmit light anymore. However, while Se is a very good glass former, telluride glasses tend to crystallize easily due to the metallic nature of Te bonds. Hence, further work is under way to stabilize the glass composition for fibers drawing and to lower the optical losses for improving their sensitivity as bio-sensors.

  9. Effect of He{sup +} irradiation on the optical properties of vacuum evaporated silver indium selenide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Santhosh Kumar, M.C., E-mail: santhoshmc@yahoo.co [Advanced Materials Laboratory, Department of Physics, National Institute of Technology, Tiruchirappalli, Tamil Nadu 620 015 (India); Pradeep, B. [Solid State Physics Laboratory, Department of Physics, Cochin University of Science and Technology, Cochin, Kerala 682 022 (India)

    2010-04-09

    We prepared polycrystalline silver indium selenide thin films by vacuum evaporation on glass substrate at a high temperature using the stoichiometric powder. The samples were subjected to the irradiation of 1.26 M eV He{sup +} ion. The effect of irradiation on the optical properties has been investigated for different fluencies of He{sup +}. The thin films were characterized by X-ray diffraction and UV-vis-NIR spectroscopy. It is observed that the band gap of silver indium selenide thin films decreases gradually from 1.17 to 0.82 eV with ion fluency.

  10. Combined detectors of charged particles based on zinc selenide scintillators and silicon photodiodes

    CERN Document Server

    Ryzhikov, V D; Starzhinskij, N G

    2001-01-01

    combined detectors of charged particles are described based on zinc selenide (Zn Se(Te)) crystals,silicon photodiodes and charges-sensitive amplifiers. Zn Se(Te) scintillators are characterized by high alpha to beta ratio (approx 1.0), good scintillation efficiency (up to 22%),and high radiation stability (up to 100 Mrad),together with good spectral matching with silicon PIN photodiodes. The signal coming from the photodiode in the two modes (photoreceiver and semiconductor detector) differ in the amplitude values and pulse duration, which opens new possibilities for development and application of such combined detectors.

  11. Structural, optical and electrical properties of chemically deposited copper selenide films

    Indian Academy of Sciences (India)

    R H Bari; V Ganesan; S Potadar; L A Patil

    2009-02-01

    Stoichiometric and nonstoichiometric thin films of copper selenide have been prepared by chemical bath deposition technique at temperature below 60°C on glass substrate. The effect of nonstoichiometry on the optical, electrical and structural properties of the film was studied. The bandgap energy was observed to increase with the increase in at % of copper in composition. The grain size was also observed to increase with the decrease of at % of copper in composition. The films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDS), absorption spectroscopy, and AFM. The results are discussed and interpreted.

  12. Ablation and ultrafast dynamics of zinc selenide under femtosecond laser irradiation

    Institute of Scientific and Technical Information of China (English)

    Xiaofeng Wang; Tianqing Jia; Xiaoxi Li; Chengbin Li; Donghai Feng; Haiyi Sun; Shizhen Xu; Zhizhan Xu

    2005-01-01

    The ablation in zinc selenide (ZnSe) crystal is studied by using 150-fs, 800-nm laser system. The images of the ablation pit measured by scanning electronic microscope (SEM) show no thermal stress and melting dynamics. The threshold fluence is measured to be 0.7 J/cm2. The ultrafast ablation dynamics is studied by using pump and probe method. The result suggests that optical breakdown and ultrafast melting take place in ZnSe irradiated under femtosecond laser pulses.

  13. TOPO-capped silver selenide nanoparticles and their incorporation into polymer nanofibers using electrospinning technique

    Energy Technology Data Exchange (ETDEWEB)

    More, D.S. [Department of Chemistry, Faculty of Applied and Computer Sciences, Vaal University of Technology, Private Bag X021, Vanderbijlpark 1900 (South Africa); Moloto, M.J., E-mail: makwenam@vut.ac.za [Department of Chemistry, Faculty of Applied and Computer Sciences, Vaal University of Technology, Private Bag X021, Vanderbijlpark 1900 (South Africa); Moloto, N. [School of Chemistry, Faculty of Science, University of the Witwatersrand, Private Bag 3, Johannesburg 2050 (South Africa); Matabola, K.P. [Nanotechnology Innovation Centre, Advanced Materials Division, Mintek, Private Bag X3015, Randburg 2125 South Africa (South Africa)

    2015-05-15

    Highlights: • Ag{sub 2}Se nanoparticles produced spherical particles with sizes 12 nm (180 °C) and 27 nm (200 °C). • Higher temperature produced increased particle size (∼75 nm) and changed in shape. • Ag{sub 2}Se nanoparticles (0.2–0.6%) added into PVP (35–45%) to yield reduced fiber beading. • Polymer nanofibers electrospun at 11–20 kV produced fiber diameters of 425–461 nm. • Optical properties in the fibers were observed due to the Ag{sub 2}Se nanoparticles loaded. - Abstract: Electrospinning is the most common technique for fabricating polymer fibers as well as nanoparticles embedded polymer fibers. Silver selenide nanoparticles were synthesized using tri-n-octylphosphine (TOP) as solvent and tri-n-octylphosphine oxide (TOPO) as capping environment. Silver selenide was prepared by reacting silver nitrate and selenium with tri-n-octylphosphine (TOP) to form TOP–Ag and TOP–Se solutions. Both absorption and emission spectra signify the formation of nanoparticles as well as the TEM which revealed spherical particles with an average particle size of 22 nm. The polymer, PVP used was prepared at concentrations ranging from (35 to 45 wt%) and the TOPO-capped silver selenide nanoparticles (0.2 and 0.6 wt%) were incorporated into them and electrospun by varying the voltage from 11 to 20 kV. The SEM images of the Ag{sub 2}Se/PVP composite fibers revealed the fibers of diameters with average values of 425 and 461 nm. The X-ray diffraction results show peaks which were identified due to α-Ag{sub 2}Se body centered cubic compound. The sharp peak observed for all the samples at 2θ = 44.5 suggest the presence of Ag in the face centered cubic which can be attributed to higher concentration of silver nitrate used with molar ratio of selenium to silver and the abundance of silver in the silver selenide crystal. Fourier transform infrared spectroscopy, thermogravimetric analysis (TGA) and ultraviolet–visible spectroscopy were used to characterize the

  14. Polarity and structure peculiarities of trialkylphosphine oxides, sulfides, selenides and tellurides

    International Nuclear Information System (INIS)

    Using the quantum-chemical calculations structural characteristics of trialkylphosphine oxides, sulfates, selenides and tellurides (Alk3P=X; X O, S, Se, Te) are obtained, which are in good agreement with literature X-ray structural analysis and gas-phase electron diffraction data. The P=X bonds polarity is determined in the framework of vector-additive scheme on the base of experimental data on components dipole moments and using different base series of molecules geometry parameters. It is shown that increasing of bond moment P=X in the X = O, S, Se, Te series takes place through dipole length increasing

  15. Solution-Liquid-Solid Synthesis of Hexagonal Nickel Selenide Nanowire Arrays with a Nonmetal Catalyst.

    Science.gov (United States)

    Xu, Kun; Ding, Hui; Jia, Kaicheng; Lu, Xiuli; Chen, Pengzuo; Zhou, Tianpei; Cheng, Han; Liu, Si; Wu, Changzheng; Xie, Yi

    2016-01-26

    Inorganic nanowire arrays hold great promise for next-generation energy storage and conversion devices. Understanding the growth mechanism of nanowire arrays is of considerable interest for expanding the range of applications. Herein, we report the solution-liquid-solid (SLS) synthesis of hexagonal nickel selenide nanowires by using a nonmetal molecular crystal (selenium) as catalyst, which successfully brings SLS into the realm of conventional low-temperature solution synthesis. As a proof-of-concept application, the NiSe nanowire array was used as a catalyst for electrochemical water oxidation. This approach offers a new possibility to design arrays of inorganic nanowires. PMID:26695560

  16. Electrical properties of silver selenide thin films prepared by reactive evaporation

    Indian Academy of Sciences (India)

    M C Santhosh Kumar; B Pradeep

    2002-10-01

    The electrical properties of silver selenide thin films prepared by reactive evaporation have been studied. Samples show a polymorphic phase transition at a temperature of 403 ± 2 K. Hall effect study shows that it has a mobility of 2000 cm2V–1s–1 and carrier concentration of 1018 cm–3 at room temperature. The carriers are of -type. X-ray diffraction study indicates that the as-prepared films are polycrystalline in nature. The lattice parameters were found to be = 4.353 Å, = 6.929 Å and = 7.805 Å.

  17. Dissimilatory Reduction of Elemental Selenium to Selenide in Sediments and Anaerobic Cultures of Selenium Respiring Bacteria

    Science.gov (United States)

    Herbel, M. J.; Switzer-Blum, J.; Oremland, R. S.

    2001-12-01

    Selenium contaminated environments often contain elemental Se (Se0) in their sediments that originates from dissimilatory reduction of Se oxyanions. The forms of Se in sedimentary rocks similarly contain high proportions of Se0, but much of the Se is also in the form of metal selenides, Se-2. It is not clear if the occurrence of these selenides is due to microbial reduction of Se0, or some other biological or chemical process. In this investigation we examined the possibility that bacterial respiratory reduction of Se0 to Se-2 could explain the presence of the latter species in sedimentary rocks. We conducted incubations of anoxic sediment slurries amended with different forms of Se0. High levels of Se0 (mM) were added to San Francisco Bay sediments in order to enhance the detection of soluble HSe-, which was precipitated with Cu2+ then redissolved and quantified by ICP-MS. Concentrations of HSe- were highest in live samples amended with red amorphous Se0 formed by either microbial reduction of Se+4 ("biogenic Se0") or by chemical oxidation of H2Se(g) ("chem. Se0"); very little HSe- was formed in those amended with black crystalline Se0, indicating the general lack of reactivity of this allotrope. Controls poisoned with 10% formalin did not produce HSe- from additions of chem. Se0. Reduction of both forms of red amorphous Se0 to HSe- occurred vigorously in growing cultures of Bacillus selenitireducens, an anaerobic halophile previously isolated from sediments of Mono Lake, CA. Up to 73% and 68% of red amorphous, biogenic Se0 or chem. Se0, respectively, was reduced to HSe- during growth of B. selenitireducens, (incubation time ~ 200 hrs): oxidation of lactate to acetate as well as cell density increases indicated that a dissimilatory reduction pathway was likely. Reduction was most enhanced when cells were previously grown on elemental sulfur or Se+4. In contrast to the growth experiments, washed cell suspensions of B. selenitireducens exhibited no HSe- production

  18. Enhanced performance of hybrid solar cells using longer arms of quantum cadmium selenide tetrapods

    KAUST Repository

    Lee, Kyu-Sung

    2011-12-01

    We demonstrate that enhanced device performance of hybrid solar cells based on tetrapod (TP)-shaped cadmium selenide (CdSe) nanoparticles and conjugated polymer of poly (3-hexylthiophene) (P3HT) can be obtained by using longer armed tetrapods which aids in better spatial connectivity, thus decreasing charge hopping events which lead to better charge transport. Longer tetrapods with 10 nm arm length lead to improved power conversion efficiency of 1.12% compared to 0.80% of device having 5 nm short-armed tetrapods:P3HT photoactive blends.

  19. Geochemical Studies on Dachang Antimony Ore Deposit in Qinglong,Guizhou Province

    Institute of Scientific and Technical Information of China (English)

    张启厚

    1999-01-01

    The Dachang antimony deposit in Qinglong,Guizhou Province,is strictly controlled by the “Dachang Layer” which is a complex altered rock occurring at unconformity between the Permian Emeishan basalt and the Maokou limestone.Based on the studies of the hanging-and foot-wall rocks,the trace elements and REE contents of the rocks and ores and heavy placer minerals in the basalt,this paper is focused on the relations between these data and the “Dachang Layer”and its hanging- and oot-wall rocks.The author pointed out that the “Dachang Layer” and basalt are the source-beds of antimony;ilmenite and magnetite are the major mineral carriers of antimony.In the processes of halmyrosis and burial metamorphism of the “Dachang Layer” an basalt,antimony was mobilized along with the mobilization of iron and was preliminarily concentrated in the“ Dachang Layer”.

  20. Effect of filler on the self-lubrication performance of graphite antimony composites

    Institute of Scientific and Technical Information of China (English)

    WANG Qi-li; HU Ya-fei; HE Min

    2008-01-01

    Graphite antimony composites were prepared using a mechanical pressure infiltration method to force molten antimony into graphite preforms having a percolation micro-structure and a hop-pocket power filler. The micro-structural and macroscopic properties of the graphite antimony composites were analysed. Observations included metallographic analysis, physical properties and friction and wear behaviour. The results show that the wear loss is decreased by 12.24% and that the friction coefficient is re-duced by 32.61% after hop-pocket power was used. The research indicates that the hop-pocket power method gives a useful way to reduce friction coefficients and wear loss, and to increase service life and self-lubrication properties, of the graphite antimony seal-ing material as compared to carbon black.

  1. Geochemistries of arsenic, antimony, mercury, and related elements in sediments of puget sound

    Science.gov (United States)

    Crecelius, E.A.; Bothner, Michael H.; Carpenter, R.

    1975-01-01

    The natural distributions of arsenic, antimony mercury, chromium, cobalt, iron, aluminum, and carbon in the surface sediments of Puget Sound are perturbed by two major anthropogenic sources of trace metals: a copper smelter near Tacoma, Wash., that discharges large amounts of arsenic and antimony, and a chlor-alkali plant in Bellingham, Wash., which, in the recent past, discharged significant amounts of mercury. Arsenic and antimony inputs from the smelter over the past 80 years are evident in sediment cores whose accumulation rates have been determined by the lead-210 technique. An arsenic budget for Puget Sound reveals the importance of atmospheric input resulting from smokestack emissions of the smelter. Chemical extraction studies of sediments showed that more than 82% of the mercury was associated with easily oxidizable organic matter, whereas about 50% of both arsenic and antimony was associated with extractable iron and aluminum compounds.

  2. 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.

  3. Crystal structure and thermodynamic properties of potassium antimony tungsten oxide

    Energy Technology Data Exchange (ETDEWEB)

    Knyazev, Aleksandr V., E-mail: knav@uic.nnov.ru [Nizhny Novgorod State University, Gagarin Prospekt 23/2, Nizhny Novgorod, 603950 (Russian Federation); Tananaev, Ivan G. [Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, 31 Leninsky prospect, Moscow GSP-1, 119991 (Russian Federation); Kuznetsova, Nataliya Yu.; Smirnova, Nataliya N.; Letyanina, Irene A.; Ladenkov, Igor V. [Nizhny Novgorod State University, Gagarin Prospekt 23/2, Nizhny Novgorod, 603950 (Russian Federation)

    2010-02-20

    In the present work potassium antimony tungsten oxide with pyrochlore structure is refined by the Rietveld method (space group Fd3m, Z = 8). The temperature dependences of heat capacity have been measured for the first time in the range from 7 to 370 K for this compound. The experimental data were used to calculate standard thermodynamic functions, namely the heat capacity C{sub p}{sup o}(T), enthalpy H{sup o}(T) - H{sup o}(0), entropy S{sup o}(T) - S{sup o}(0) and Gibbs function G{sup o}(T) - H{sup o}(0), for the range from T {yields} 0 to 370 K. The differential scanning calorimetry was applied to measure the incongruent melting temperature of compound under study. The high-temperature X-ray diffraction was used for the determining thermal expansion coefficients.

  4. Coherent and Incoherent Structural Dynamics in Laser-Excited Antimony

    CERN Document Server

    Waldecker, Lutz; Bertoni, Roman; Vasileiadis, Thomas; Garcia, Martin E; Zijlstra, Eeuwe S; Ernstorfer, Ralph

    2016-01-01

    We investigate the excitation of phonons in photoexcited antimony and demonstrate that the entire electron-lattice interactions, in particular coherent and incoherent electron-phonon coupling, can be probed simultaneously. Using femtosecond electron diffraction (FED) with high temporal resolution, we observe the coherent excitation of the fully symmetric \\Ag\\ optical phonon mode via the shift of the minimum of the atomic potential energy surface. Molecular dynamics simulations are performed to quantify the change in lattice potential and the associated real-space amplitude of the coherent atomic oscillations. In addition, our experimental configuration allows observing the energy transfer from electrons to phonons via incoherent electron-lattice scattering events. Applying a modified two-temperature model, the electron-phonon coupling is determined from the data as a function of electronic temperature.

  5. Atomistic mechanisms governing structural stability change of zinc antimony thermoelectrics

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xiaolong [Frontier Institute of Science and Technology, Xi' an Jiaotong University, Xi' an 710054 (China); Lin, Jianping, E-mail: jaredlin@163.com [School of Materials Science and Engineering, Xiamen University of Technology, Xiamen 361024 (China); Qiao, Guanjun [State Key Laboratory for Mechanical Behavior of Materials, Xi' an Jiaotong University, Xi' an 710049 (China); Wang, Zhao, E-mail: zwangzhao@gmail.com [Frontier Institute of Science and Technology, Xi' an Jiaotong University, Xi' an 710054 (China); State Key Laboratory for Mechanical Behavior of Materials, Xi' an Jiaotong University, Xi' an 710049 (China)

    2015-01-05

    The structural stability of thermoelectric materials is a subject of growing importance for their energy harvesting applications. Here, we study the microscopic mechanisms governing the structural stability change of zinc antimony at its working temperature, using molecular dynamics combined with experimental measurements of the electrical and thermal conductivity. Our results show that the temperature-dependence of the thermal and electrical transport coefficients is strongly correlated with a structural transition. This is found to be associated with a relaxation process, in which a group of Zn atoms migrates between interstitial sites. This atom migration gradually leads to a stabilizing structural transition of the entire crystal framework, and then results in a more stable crystal structure of β–Zn{sub 4}Sb{sub 3} at high temperature.

  6. Antimonial drugs entrapped into phosphatidylserine liposomes: physicochemical evaluation and antileishmanial activity

    OpenAIRE

    Samanta Etel Treiger Borborema; João Alberto Osso Junior; Heitor Franco de Andrade Junior; Nanci do Nascimento

    2016-01-01

    Abstract: INTRODUCTION: Leishmaniasis is a disease caused by the protozoan Leishmania that resides mainly in mononuclear phagocytic system tissues. Pentavalent antimonials are the main treatment option, although these drugs have toxic side effects and high resistance rates. A potentially alternative and more effective therapeutic strategy is to use liposomes as carriers of the antileishmanial agents. The aims of this study were to develop antimonial drugs entrapped into phosphatidylserine l...

  7. New low-antimony alloy for straps and cycling service in lead-acid batteries

    Science.gov (United States)

    Prengaman, R. David

    Lead-antimony alloys used for the positive grids in lead-acid batteries for cycling service have generally used antimony contents of 4.5 wt.% and above. Tubular batteries for cycling service that impart high compression of the active material to the grid surface via gauntlet use alloys with antimony contents as low as 1.5 wt.%. These batteries are generally employed in less-severe cycling service. Value-regulated lead-acid (VRLA) batteries can give good cycling service without lead-antimony in the positive grid, but require a high tin content and high compression. The change in automotive battery positive grid alloys to lead-calcium-tin and the tin contents of VRLA positive grids and straps have dramatically increased the tin content of the recycled grid and strap lead in the USA, Europe, and Australia. The higher tin contents can contaminate the lead used for lead-antimony battery grids and generally must be removed to low levels to meet the specifications. This study describes a low-antimony alloy that contains a substantial amount of tin. The high tin content reduces the rate of corrosion of low-antimony positive grid alloys, improves conductivity, increases the bond between the grid and the active material, and cycles as well as the traditional 5-6 wt.% antimony alloys employed in conventional flat-plate batteries. The alloy is also used as a corrosion-resistant cast-on strap alloy for automotive batteries for high temperature service, as well as for posts, bushings, and connectors for all wet batteries.

  8. Effect of Antimony, Phosphorous and Salinity on Growth, Root Membrane Permeability and Root Antimony, Iron and Zinc Concentration of Corn in Hydroponic Media

    OpenAIRE

    H. Barangizi; M. Afyuni; B. Rezaee

    2010-01-01

    Antimony (Sb) pollution has increased in recent years because of human activities and extensive usage of antimony compounds. To date, only a few researches have been conducted in this field in Iran. The purpose of this research is to determine fresh and dry weight, root permeability percentage and root concentration of Sb, Fe and Zn in the corn. This greenhouse research was performed in hydroponics. A factorial experiment (3 × 2 × 3) with three Sb concentrations (0, 6, 18 mgL-1), with and wit...

  9. Compatibility of Pt-3008 with selected components of the selenide isotope generator system

    International Nuclear Information System (INIS)

    The first in a new generation of radioisotopic thermoelectric generators being built by Teledyne Energy Systems and designated the Selenide Isotope Generator has thermoelectric materials that can be degraded by reaction with O2, H2O, CO, and other gases. Consequently, for at least the first ground demonstration system a protective xenon atmosphere will be maintained over the thermoelectrics. The high-temperature portion of the atmosphere-retaining structure will be fabricated from the alloy Pt-3008 (Pt--30 wt % Rh--8 wt % W), which was developed at Oak Ridge National Laboratory. For this application Pt-3008 must be compatible with the various insulations and thermoelectric materials. A study of the compatibility of Pt-3008 with these materials and showed that Pt-3008 was embrittled after exposure to some of the insulations that were not adequately outgassed and by one of the thermoelectric materials (Cu2Se) in some of the isothermal tests. It is believed that Pt-3008 will be compatible with the Selenide Isotope Generator materials when they are well outgassed and under the temperature gradient conditions of the operating system

  10. Chemical Potential Tuning and Enhancement of Thermoelectric Properties in Indium Selenides

    Directory of Open Access Journals (Sweden)

    Jong-Soo Rhyee

    2015-03-01

    Full Text Available Researchers have long been searching for the materials to enhance thermoelectric performance in terms of nano scale approach in order to realize phonon-glass-electron-crystal and quantum confinement effects. Peierls distortion can be a pathway to enhance thermoelectric figure-of-merit ZT by employing natural nano-wire-like electronic and thermal transport. The phonon-softening known as Kohn anomaly, and Peierls lattice distortion decrease phonon energy and increase phonon scattering, respectively, and, as a result, they lower thermal conductivity. The quasi-one-dimensional electrical transport from anisotropic band structure ensures high Seebeck coefficient in Indium Selenide. The routes for high ZT materials development of In4Se3−δ are discussed from quasi-one-dimensional property and electronic band structure calculation to materials synthesis, crystal growth, and their thermoelectric properties investigations. The thermoelectric properties of In4Se3−δ can be enhanced by electron doping, as suggested from the Boltzmann transport calculation. Regarding the enhancement of chemical potential, the chlorine doped In4Se3−δCl0.03 compound exhibits high ZT over a wide temperature range and shows state-of-the-art thermoelectric performance of ZT = 1.53 at 450 °C as an n-type material. It was proven that multiple elements doping can enhance chemical potential further. Here, we discuss the recent progress on the enhancement of thermoelectric properties in Indium Selenides by increasing chemical potential.

  11. Asymmetric supercapacitors with metal-like ternary selenides and porous graphene electrodes

    KAUST Repository

    Xia, Chuan

    2016-04-14

    Asymmetric supercapacitors provide a promising approach to fabricate capacitive energy storage devices with high energy and power densities. In this work, asymmetric supercapacitors with excellent performance have been fabricated using ternary (Ni, Co)0.85Se on carbon fabric as bind-free positive electrode and porous free-standing graphene films as negative electrode. Owing to their metal-like conductivity (~1.67×106 S m−1), significant electrochemical activity, and superhydrophilic nature, our nanostructured ternary nickel cobalt selenides result in a much higher areal capacitance (2.33 F cm−2 at 4 mA cm−2), better rate performance and cycling stability than their binary selenide equivalents, and other ternary oxides and chalcogenides. Those hybrid supercapacitors can afford impressive areal capacitance and stack capacitance of 529.3 mF cm−2 and 6330 mF cm−3 at 1 mA cm−2, respectively. More impressively, our optimized asymmetric device operating at 1.8 V delivers a very high stack energy density of 2.85 mWh cm−3 at a stack power density of 10.76 mW cm−3, as well as 85% capacitance retention after 10,000 continuous charge-discharge cycles. Even at a high stack power density of 1173 mW cm−3, this device still deliveries a stack energy density of 1.19 mWh cm−3, superior to most of the reported supercapacitors.

  12. Effects of antimony on aquatic organisms (Larva and embryo of Oryzias latipes, Moina macrocopa, Simocephalus mixtus, and Pseudokirchneriella subcapitata).

    Science.gov (United States)

    Nam, Sun-Hwa; Yang, Chang-Yong; An, Youn-Joo

    2009-05-01

    Antimony is widespread in aquatic environment. Trivalent forms of antimony are known to be more toxic than other chemical species of antimony. In the present study, antimony potassium tartrate (APT), the trivalent inorganic forms of antimony, was selected as a test antimony compound due to its high water solubility. The effects of antimony on Japanese medaka (Oryzias latipes), planktonic crustacea (Moina macrocopa and Simocephalus mixtus), and green algae (Pseudokirchneriella subcapitata) were evaluated. Larval survival and the embryonic development were measured for fish assay. APT was less toxic to larval medaka (24-h LC50, 261; 48-h LC50, 238 mg L(-1)). Simocephalus mixtus was killed by very low concentrations of APT (24-h LC50, 4.92 mg L(-1)), and antimony was also toxic to Moina macrocopa (24-h LC50, 12.83 mg L(-1)). Toxicities of APT to S. mixtus and Moina macrocopa were about 50 and 20 times more toxic to Oryzias latipes larvae, respectively, in terms of 24-h LC50 value. Growth inhibition of Pseudokirchneriella subcapitata was observed in the presence of APT (72-h EC50, 206 mg L(-1)). This study demonstrated that APT is more toxic to planktonic crustacea than fish and green algae, and planktonic crustacea appears a better indicator of antimony pollution in aquatic environment. PMID:19264343

  13. Methylselenol formed by spontaneous methylation of selenide is a superior selenium substrate to the thioredoxin and glutaredoxin systems.

    Directory of Open Access Journals (Sweden)

    Aristi P Fernandes

    Full Text Available Naturally occurring selenium compounds like selenite and selenodiglutathione are metabolized to selenide in plants and animals. This highly reactive form of selenium can undergo methylation and form monomethylated and multimethylated species. These redox active selenium metabolites are of particular biological and pharmacological interest since they are potent inducers of apoptosis in cancer cells. The mammalian thioredoxin and glutaredoxin systems efficiently reduce selenite and selenodiglutathione to selenide. The reactions are non-stoichiometric aerobically due to redox cycling of selenide with oxygen and thiols. Using LDI-MS, we identified that the addition of S-adenosylmethionine (SAM to the reactions formed methylselenol. This metabolite was a superior substrate to both the thioredoxin and glutaredoxin systems increasing the velocities of the nonstoichiometric redox cycles three-fold. In vitro cell experiments demonstrated that the presence of SAM increased the cytotoxicity of selenite and selenodiglutathione, which could neither be explained by altered selenium uptake nor impaired extra-cellular redox environment, previously shown to be highly important to selenite uptake and cytotoxicity. Our data suggest that selenide and SAM react spontaneously forming methylselenol, a highly nucleophilic and cytotoxic agent, with important physiological and pharmacological implications for the highly interesting anticancer effects of selenium.

  14. Arsenic and Antimony Content in Soil and Plants from Baia Mare Area, Romania

    Directory of Open Access Journals (Sweden)

    Gabriela Oprea

    2010-01-01

    Full Text Available Problem statement: The objective of this research was to evaluate the degree of soil contamination with arsenic and antimony in Baia Mare, a nonferrous mining and metallurgical center located in the North West region of Romania. The soil in the area is affected by the emissions of powders containing metals from metallurgical factories. Previous studies indicated the soil contamination with copper, zinc, cadmium and lead, but there is few data about the actual level of soil pollution with arsenic and antimony. Approach: The soil samples were collected from 2 districts of Baia Mare: Ferneziu, which is located in the proximity of a lead smelter and Săsar district which is located along the Sasar River in the preferential direction of the wind over a metallurgical factory producing lead. As reference was considered Dura area located in a less polluted hilly area, in the west part of the town. Samples of soil and plants from the residential area of Ferneziu, Săsar and Dura districts were collected. The arsenic determination was carried out by inductively coupled plasma atomic emission spectrometry and the antimony determination by inductively coupled plasma mass spectrometry. Results: In Ferneziu area, the concentration of arsenic in soil ranged between 0.25 and 255 mg kg-1. In Săsar district the arsenic concentration in the soil ranged between 5.5 and 295 mg kg-1. Regarding antimony, in Ferneziu area the concentration ranged between 5.3 and 40.6 mg kg-1; while in Săsar, antimony soils concentrations vary in the range: 0.9-18.4. Arsenic and antimony concentrations in plants were low for almost of the samples, both in Ferneziu and Săsar area indicating a low mobility of these elements in the studied soils. Conclusion: This study indicated the soil pollution with arsenic both in Ferneziu district and in Săsar district. The soil pollution with antimony was found especially in Ferneziu district.

  15. Antimony distribution and mobility in topsoils and plants (Cytisus striatus, Cistus ladanifer and Dittrichia viscosa) from polluted Sb-mining areas in Extremadura (Spain)

    International Nuclear Information System (INIS)

    A study about topsoil antimony distribution and mobility from the soils to the biomass has been afforded in three abandoned Sb mining areas located at Extremadura. Physico-chemical characteristics of the soils and total antimony levels were measured in soils and autochthonous plant species (Cytisus striatus, Cistus ladanifer and Dittrichia viscosa). Comparison with corresponding values in reference areas isolated from the mining activities is discussed. Antimony mobility in the soils was estimated by measuring the water extractable fraction; low results were obtained for the three soil areas, with no statistical differences. Plant ability to accumulate antimony was estimated by use of plant accumulation coefficients (PAC). Seasonal (spring vs. autumn) effects on the antimony content in the plant species. Cytisus striatus from Mari Rosa mine presented antimony excluder characteristics, whereas Dittrichia viscosa specimens growing in San Antonio mine showed a significant antimony bioaccumulation. - Bioaccumulation of antimony in vegetal species growing in mining areas

  16. Antimony distribution and mobility in topsoils and plants (Cytisus striatus, Cistus ladanifer and Dittrichia viscosa) from polluted Sb-mining areas in Extremadura (Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Murciego, A. Murciego [Area de Cristalografia y Mineralogia, Universidad de Extremadura, Avda. Elvas, s/n, E-06071 Badajoz (Spain); Sanchez, A. Garcia [IRNA-CSIC, Departamento de Geoquimica Ambiental, Aptdo. 257, Salamanca (Spain); Gonzalez, M.A. Rodriguez [Area de Cristalografia y Mineralogia, Universidad de Extremadura, Avda. Elvas, s/n, E-06071 Badajoz (Spain); Gil, E. Pinilla [Departamento de Quimica Analitica y Electroquimica, Facultad de Ciencias, Universidad de Extremadura, Avda. Elvas, s/n, E-06071 Badajoz (Spain)]. E-mail: epinilla@unex.es; Gordillo, C. Toro [Departamento de Quimica Analitica y Electroquimica, Facultad de Ciencias, Universidad de Extremadura, Avda. Elvas, s/n, E-06071 Badajoz (Spain); Fernandez, J. Cabezas [Area de Ecologia, Universidad de Extremadura, Avda. Elvas, s/n, E-06071 Badajoz (Spain); Triguero, T. Buyolo [Area de Ecologia, Universidad de Extremadura, Avda. Elvas, s/n, E-06071 Badajoz (Spain)

    2007-01-15

    A study about topsoil antimony distribution and mobility from the soils to the biomass has been afforded in three abandoned Sb mining areas located at Extremadura. Physico-chemical characteristics of the soils and total antimony levels were measured in soils and autochthonous plant species (Cytisus striatus, Cistus ladanifer and Dittrichia viscosa). Comparison with corresponding values in reference areas isolated from the mining activities is discussed. Antimony mobility in the soils was estimated by measuring the water extractable fraction; low results were obtained for the three soil areas, with no statistical differences. Plant ability to accumulate antimony was estimated by use of plant accumulation coefficients (PAC). Seasonal (spring vs. autumn) effects on the antimony content in the plant species. Cytisus striatus from Mari Rosa mine presented antimony excluder characteristics, whereas Dittrichia viscosa specimens growing in San Antonio mine showed a significant antimony bioaccumulation. - Bioaccumulation of antimony in vegetal species growing in mining areas.

  17. The MRP1-mediated effluxes of arsenic and antimony do not require arsenic-glutathione and antimony-glutathione complex formation.

    Science.gov (United States)

    Salerno, Milena; Petroutsa, Maria; Garnier-Suillerot, Arlette

    2002-04-01

    Arsenic trioxide is an effective treatment for acute promyelocytic leukemia, but resistance to metalloid salts is found in humans. Using atomic absorption spectroscopy, we have measured the rate of uptake of arsenic trioxide and of antimony tartrate in GLC4 and GLC4/ADR cells overexpressing MRP1 and the rate of their MRP1-mediated effluxes as a function of the intracellular GSH concentration. In sensitive cells, after 1 h, a pseudosteady state is reached where intra- and extracellular concentrations of metalloid are the same. This precludes the formation, at short term, of complexes between arsenic or antimony with GSH. In resistant cells reduced intracellular accumulation of arsenic (or antimony), reflecting an increased rate of arsenic (or antimony) efflux from the cells, is observed. No efflux of the metalloid is observed in GSH depleted cells. The two metalloids and GSH are pumped out by MRP1 with the same efficiency. Moreover for the three compounds 50% of the efflux is inhibited by 2 microM MK571. This led us to suggest that As- and Sb-containing species could be cotransported with GSH. PMID:12018890

  18. 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 < 0.001). There was no significant difference of hair antimony concentrations among different occupation types in e-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. PMID:25501644

  19. Colloidally stable selenium@copper selenide core@shell nanoparticles as selenium source for manufacturing of copper-indium-selenide solar cells.

    Science.gov (United States)

    Dong, Hailong; Quintilla, Aina; Cemernjak, Marco; Popescu, Radian; Gerthsen, Dagmar; Ahlswede, Erik; Feldmann, Claus

    2014-02-01

    Selenium nanoparticles with diameters of 100-400nm are prepared via hydrazine-driven reduction of selenious acid. The as-prepared amorphous, red selenium (a-Se) particles were neither a stable phase nor were they colloidally stable. Due to phase transition to crystalline (trigonal), grey selenium (t-Se) at or even below room temperature, the particles merged rapidly and recrystallized as micronsized crystal needles. As a consequence, such Se particles were not suited for layer deposition and as a precursor to manufacture thin-film CIS (copper indium selenide/CuInSe2) solar cells. To overcome this restriction, Se@CuSe core@shell particles are presented here. For these Se@CuSe core@shell nanoparticles, the phase transition a-Se→t-Se is shifted to temperatures higher than 100°C. Moreover, a spherical shape of the particles is retained even after phase transition. Composition and structure of the Se@CuSe core@shell nanostructure are evidenced by electron microscopy (SEM/STEM), DLS, XRD, FT-IR and line-scan EDXS. As a conceptual study, the newly formed Se@CuSe core@shell nanostructures with CuSe acting as a protecting layer to increase the phase-transition temperature and to improve the colloidal stability were used as a selenium precursor for manufacturing of thin-film CIS solar cells and already lead to conversion efficiencies up to 3%. PMID:24267336

  20. Reduction of Diaryldiselenides by System of Cp2TiCl2/ BuiMgBr/ THF and Its Application in Synthesis of Unsymmetrical Diaryl Selenides

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Reduction of diaryldiselenides by the system of Cp2TiCl2/BuiMgBr/THF gave the nucleophilic arylselenium complex. They reacted with diaryl iodonium salts to afford unsymmetrical diaryl selenides in high yields.

  1. 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.

  2. Arsenic and antimony removal from drinking water by adsorption on granular ferric oxide.

    Science.gov (United States)

    Sazakli, Eleni; Zouvelou, Stavroula V; Kalavrouziotis, Ioannis; Leotsinidis, Michalis

    2015-01-01

    Arsenic and antimony occur in drinking water due to natural weathering or anthropogenic activities. There has been growing concern about their impact on health. The aim of this study was to assess the efficiency of a granular ferric oxide adsorbent medium to remove arsenic and antimony from drinking water via rapid small-scale column tests (RSSCTs). Three different water matrices - deionized, raw water treated with a reverse osmosis domestic device and raw water - were spiked with arsenic and/or antimony to a concentration of 100 μg L⁻¹. Both elements were successfully adsorbed onto the medium. The loadings until the guideline value was exceeded in the effluent were found to be 0.35-1.63 mg g⁻¹ for arsenic and 0.12-2.11 mg g⁻¹ for antimony, depending on the water matrix. Adsorption of one element was not substantially affected by the presence of the other. Aeration did not affect significantly the adsorption capacity. Granular ferric oxide could be employed for the simultaneous removal of arsenic and antimony from drinking water, whereas full-scale systems should be assessed via laboratory tests before their implementation.

  3. Determination of traces of uranium and thorium in antimony(III) oxide by ICP-MS

    International Nuclear Information System (INIS)

    Traces of uranium and thorium in antimony(III) oxide were determined by inductively coupled plasma mass spectrometry (ICP-MS). A method of vaporization as the halide was applied to the separation of the analytes from the antimony matrix. Because the above separation method is so simple, reduced of external contamination was expected. In the case of vaporization using hydrochloric acid, however, it was found that antimony trichloride ions overlapped thorium ion of 232 (m/z). To find the most suitable conditions for matrix separation, vaporization behaviors were studied by using different acidic solutions such as HBr, HBr-HClO4 and HBr-H2SO4. Neither HBr+HClO4 nor HBr+H2SO4 was able to reduce the antimony matrix down to an unaffected level on ICP-MS measurement. On the other hand, in the case of the vaporization using hydrobromic acid, almost all the antimony matrix was removed. Determination limits obtained by this method were 0.02 and 0.03 ng g-1 for uranium and thorium, respectively. (author)

  4. Antimony bioavailability: knowledge and research perspectives for sustainable agricultures.

    Science.gov (United States)

    Pierart, Antoine; Shahid, Muhammad; Séjalon-Delmas, Nathalie; Dumat, Camille

    2015-05-30

    The increasing interest in urban agriculture highlights the crucial question of crop quality. The main objectives for environmental sustainability are a decrease in chemical inputs, a reduction in the level of pollutants, and an improvement in the soil's biological activity. Among inorganic pollutants emitted by vehicle traffic and some industrial processes in urban areas, antimony (Sb) is observed on a global scale. While this metalloid is known to be potentially toxic, it can transfer from the soil or the atmosphere to plants, and accumulate in their edible parts. Urban agriculture is developing worldwide, and could therefore increasingly expose populations to Sb. The objective of this review was in consequences to gather and interpret actual knowledge of Sb uptake and bioaccumulation by crops, to reveal investigative fields on which to focus. While there is still no legal maximal value for Sb in plants and soils, light has to be shed on its accumulation and the factors affecting it. A relative absence of data exists about the role of soil flora and fauna in the transfer, speciation and compartmentation of Sb in vegetables. Moreover, little information exists on Sb ecotoxicity for terrestrial ecosystems. A human risk assessment has finally been reviewed, with particular focus on Sb bioaccessibility.

  5. The role of isomorphous substitutions in natural selenides belonging to the pyrite group

    Energy Technology Data Exchange (ETDEWEB)

    Bindi, Luca [Museo di Storia Naturale, sez. di Mineralogia e Litologia, Universita degli Studi di Firenze, via La Pira 4, I-50121 Firenze (Italy)], E-mail: luca.bindi@unifi.it; Cipriani, Curzio [Museo di Storia Naturale, sez. di Mineralogia e Litologia, Universita degli Studi di Firenze, via La Pira 4, I-50121 Firenze (Italy); Pratesi, Giovanni [Museo di Storia Naturale, sez. di Mineralogia e Litologia, Universita degli Studi di Firenze, via La Pira 4, I-50121 Firenze (Italy); Dipartimento di Scienze della Terra, Universita degli Studi di Firenze, via La Pira 4, I-50121 Firenze (Italy); Trosti-Ferroni, Renza [Dipartimento di Scienze della Terra, Universita degli Studi di Firenze, via La Pira 4, I-50121 Firenze (Italy)

    2008-07-14

    The present paper reports chemical and structural data of selenide minerals belonging to the pyrite group. Eighteen samples of minerals in this group with variable chemical composition (7 samples of penroseite, NiSe{sub 2}; 10 samples of krutaite, CuSe{sub 2}; 1 sample of trogtalite, CoSe{sub 2}) were studied by means of X-ray single-crystal diffraction and electron microprobe. On the basis of information gained from the chemical characterization, we can conclude that a complete solid solution between NiSe{sub 2} and CuSe{sub 2} exists in nature with the absence of pure end-members. Although verified only for the Ni-rich members, we also infer a solid solution between NiSe{sub 2} and CoSe{sub 2}. The unit-cell parameters were modeled using a multiple regression method as a function of the Co, Ni, and Cu contents.

  6. Optoelectronic and low temperature thermoelectric studies on nanostructured thin films of silver gallium selenide

    Science.gov (United States)

    Jacob, Rajani; Philip, Rachel Reena; Nazer, Sheeba; Abraham, Anitha; Nair, Sinitha B.; Pradeep, B.; Urmila, K. S.; Okram, G. S.

    2014-01-01

    Polycrystalline thin films of silver gallium selenide were deposited on ultrasonically cleaned soda lime glass substrates by multi-source vacuum co-evaporation technique. The structural analysis done by X-ray diffraction ascertained the formation of nano structured tetragonal chalcopyrite thin films. The compound formation was confirmed by X-ray photo-electron spectroscopy. Atomic force microscopic technique has been used for surface morphological analysis. Direct allowed band gap ˜1.78eV with high absorption coefficient ˜106/m was estimated from absorbance spectra. Low temperature thermoelectric effects has been investigated in the temperature range 80-330K which manifested an unusual increase in Seebeck coefficient with negligible phonon drag toward the very low and room temperature regime. The electrical resistivity of these n-type films was assessed to be ˜2.6Ωm and the films showed good photo response.

  7. Effect of capping agents on optical and antibacterial properties of cadmium selenide quantum dots

    Indian Academy of Sciences (India)

    Deepika; Rakesh Dhar; Suman Singh; Atul Kumar

    2015-09-01

    Cadmium selenide quantum dots (CdSe QDs) were synthesized in aqueous phase by the freezing temperature injection technique using different capping agents (viz. thioglycolic acid, 1-thioglycerol, L-cysteine). Absorption spectra of CdSe QDs exhibited a blue shift as compared to its bulk counterpart, which is an indication of quantum confinement effect. The photoluminescence spectra of CdSe QDs confirmed that the particles are poly-dispersed and possess enhanced luminescent property, depending upon the chemical nature of capping agents. The QDs have been characterized by Fourier-transform infrared spectroscopy, atomic absorption spectroscopy and transmission electron microscopy. Further, antimicrobial activity of as-prepared QDs has also been investigated using the disk diffusion method.

  8. A Rapid and Cost-Effective Laser Based Synthesis of High Purity Cadmium Selenide Quantum Dots.

    Science.gov (United States)

    Gondall, M A; Qahtan, Talal F; Dastageer, M A; Yamani, Z H; Anjum, D H

    2016-01-01

    A rapid and cost effective method is developed to synthesize high purity cadmium Selenide (CdSe) quantum dots in acetone medium using second harmonic of Nd:YAG nanosecond pulsed laser of 532 nm wavelength. The thermal agglomeration due the nanosecond pulse duration of the laser was successfully eliminated by using unfocussed laser beam and thereby providing a favorable conditions for the synthesis of quantum dots having the grain size of 3 nm. The morphological and optical characterizations like XRD, HRTEM, optical absorption of the synthesized CdSe quantum dots, reveal that the material possesses the similar characteristics of the one synthesized through cumbersome wet chemical methods. Relative to the CdSe bulk material, the synthesized CdSe quantum dots showed a blue shift in the measured band gap energy from near infrared spectral region to visible region, making this material very attractive for many solar energy harvesting applications like photo-catalysis and solar cells. PMID:27398538

  9. Radiation-induced physical ageing in network arsenic-sulfide/selenide glasses

    International Nuclear Information System (INIS)

    Effect of radiation-induced physical ageing is investigated by differential scanning calorimetry method in AsxSe100-x (10 ≤ x ≤ 42) and AsxS100-x (30 ≤ x ≤ 42) glasses. Obtained results are compared with conventional physical ageing at normal conditions. Significant radiation-induced physical ageing is recorded for glassy AsxS100-x within 30 ≤ x xSe100-x glasses from the same compositional interval do not show any measurable changes in DSC curves after γ-irradiation. Observed difference in radiation-induced physical ageing in arsenic-sulfide/selenide glasses is explained by a greater lifetime of γ-induced excitations within sulfur-based network in comparison with selenium-based one.

  10. Searching for new thermoelectric materials: some examples among oxides, sulfides and selenides

    Science.gov (United States)

    Hébert, S.; Berthebaud, D.; Daou, R.; Bréard, Y.; Pelloquin, D.; Guilmeau, E.; Gascoin, F.; Lebedev, O.; Maignan, A.

    2016-01-01

    Different families of thermoelectric materials have been investigated since the discovery of thermoelectric effects in the mid-19th century, materials mostly belonging to the family of degenerate semi-conductors. In the last 20 years, new thermoelectric materials have been investigated following different theoretical proposals, showing that nanostructuration, electronic correlations and complex crystallographic structures (low dimensional structures, large number of atoms per lattice, presence of ‘rattlers’…) could enhance the thermoelectric properties by enhancing the Seebeck coefficient and/or reducing the thermal conductivity. In this review, the different strategies used to optimize the thermoelectric properties of oxides and chalcogenides will be presented, starting with a review on thermoelectric oxides. The thermoelectric properties of sulfides and selenides will then be discussed, focusing on layered materials and low dimensional structures (TiS2 and pseudo-hollandites). Some sulfides with promising ZT values will also be presented (tetrahedrites and chalcopyrites).

  11. Photo-induced cooperative covalent-bond switching in amorphous arsenic selenide

    Energy Technology Data Exchange (ETDEWEB)

    Shpotyuk, O [Lviv Scientific Research Institute of Materials of SRC ' Carat' , 202, Stryjska str., Lviv, UA-290031 (Ukraine); Balitska, V [Lviv Scientific Research Institute of Materials of SRC ' Carat' , 202, Stryjska str., Lviv, UA-290031 (Ukraine); Filipecki, J [Institute of Physics of Jan Dlugosz University, 13/15, Al. Armii Krajowej, Czestochowa, PL-42201 (Poland)

    2005-01-01

    A microstructural mechanism of photoinduced transformations in amorphous arsenic selenide films was studied with IR Fourier-spectroscopy technique in 300-100 cm{sup -1} region. It was shown that stage of irreversible photostructural changes was connected with cooperative process of coordination defect formation accompanied by homopolar chemical bonds switching in heteropolar ones. On the contrary, reversible photoinduced effects were caused by heteropolar chemical bonds switching in homopolar ones, as well as additional channel of bridge heteropolar bonds switching in short-layer ones. The both processes were associated with formation of anomalously coordinated defect pairs and accompanying atomic displacements at the level of medium-range ordering. The developed mathematical simulation procedure testified in a favour of defect-related origin of the reversible photo-thermallyinduced transformations, since their kinetics corresponded to known stretched-exponential dependence, tending to bimolecular behaviour rather then to single-exponential one.

  12. Radiation-induced physical ageing in network arsenic-sulfide/selenide glasses

    Energy Technology Data Exchange (ETDEWEB)

    Shpotyuk, M; Golovchak, R; Kozdras, A; Shpotyuk, O, E-mail: shpotyuk@novas.lviv.ua

    2010-11-15

    Effect of radiation-induced physical ageing is investigated by differential scanning calorimetry method in As{sub x}Se{sub 100-x} (10 {<=} x {<=} 42) and As{sub x}S{sub 100-x} (30 {<=} x {<=} 42) glasses. Obtained results are compared with conventional physical ageing at normal conditions. Significant radiation-induced physical ageing is recorded for glassy As{sub x}S{sub 100-x} within 30 {<=} x < 40 range, while As{sub x}Se{sub 100-x} glasses from the same compositional interval do not show any measurable changes in DSC curves after {gamma}-irradiation. Observed difference in radiation-induced physical ageing in arsenic-sulfide/selenide glasses is explained by a greater lifetime of {gamma}-induced excitations within sulfur-based network in comparison with selenium-based one.

  13. Searching for new thermoelectric materials: some examples among oxides, sulfides and selenides.

    Science.gov (United States)

    Hébert, S; Berthebaud, D; Daou, R; Bréard, Y; Pelloquin, D; Guilmeau, E; Gascoin, F; Lebedev, O; Maignan, A

    2016-01-13

    Different families of thermoelectric materials have been investigated since the discovery of thermoelectric effects in the mid-19th century, materials mostly belonging to the family of degenerate semi-conductors. In the last 20 years, new thermoelectric materials have been investigated following different theoretical proposals, showing that nanostructuration, electronic correlations and complex crystallographic structures (low dimensional structures, large number of atoms per lattice, presence of 'rattlers'…) could enhance the thermoelectric properties by enhancing the Seebeck coefficient and/or reducing the thermal conductivity. In this review, the different strategies used to optimize the thermoelectric properties of oxides and chalcogenides will be presented, starting with a review on thermoelectric oxides. The thermoelectric properties of sulfides and selenides will then be discussed, focusing on layered materials and low dimensional structures (TiS2 and pseudo-hollandites). Some sulfides with promising ZT values will also be presented (tetrahedrites and chalcopyrites).

  14. Heterogeneous nanocomposites of silver selenide and hollow platinum nanoparticles toward methanol oxidation reaction

    Science.gov (United States)

    Cui, Penglei; He, Hongyan; Liu, Hui; Zhang, Suojiang; Yang, Jun

    2016-09-01

    Making use of the electronic coupling between different domains in composite nanomaterials is an effective way to enhance the activity of electrocatalysts. Herein, we demonstrate the preparation of nanocomposites consisting of silver selenide (Ag2Se) and platinum (Pt) nanoparticles with a hollow interior by combining the inside-out diffusion of Ag in core-shell Ag-Pt nanoparticles with the synthesis of highly active hydrophobic Se species. In specific, the Ag2Se-hPt nanocomposites are found to have superior activity and stability for methanol oxidation reaction in an acidic condition due to the strong electronic coupling effect between semiconductor and metal domains. This strategy may provide a greener and less expensive way to the large-scale synthesis of Pt-based nanocomposites, and might be used to generate other heterogeneous nanomaterials with technological importance.

  15. Photo-induced cooperative covalent-bond switching in amorphous arsenic selenide

    International Nuclear Information System (INIS)

    A microstructural mechanism of photoinduced transformations in amorphous arsenic selenide films was studied with IR Fourier-spectroscopy technique in 300-100 cm-1 region. It was shown that stage of irreversible photostructural changes was connected with cooperative process of coordination defect formation accompanied by homopolar chemical bonds switching in heteropolar ones. On the contrary, reversible photoinduced effects were caused by heteropolar chemical bonds switching in homopolar ones, as well as additional channel of bridge heteropolar bonds switching in short-layer ones. The both processes were associated with formation of anomalously coordinated defect pairs and accompanying atomic displacements at the level of medium-range ordering. The developed mathematical simulation procedure testified in a favour of defect-related origin of the reversible photo-thermallyinduced transformations, since their kinetics corresponded to known stretched-exponential dependence, tending to bimolecular behaviour rather then to single-exponential one

  16. Searching for new thermoelectric materials: some examples among oxides, sulfides and selenides

    International Nuclear Information System (INIS)

    Different families of thermoelectric materials have been investigated since the discovery of thermoelectric effects in the mid-19th century, materials mostly belonging to the family of degenerate semi-conductors. In the last 20 years, new thermoelectric materials have been investigated following different theoretical proposals, showing that nanostructuration, electronic correlations and complex crystallographic structures (low dimensional structures, large number of atoms per lattice, presence of ‘rattlers’…) could enhance the thermoelectric properties by enhancing the Seebeck coefficient and/or reducing the thermal conductivity. In this review, the different strategies used to optimize the thermoelectric properties of oxides and chalcogenides will be presented, starting with a review on thermoelectric oxides. The thermoelectric properties of sulfides and selenides will then be discussed, focusing on layered materials and low dimensional structures (TiS2 and pseudo-hollandites). Some sulfides with promising ZT values will also be presented (tetrahedrites and chalcopyrites). (topical review)

  17. Structural, morphological and optical properties of nanocrystalline cadmium selenide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Khomane, A.S., E-mail: ashok_khomane@rediffmail.co [Department of Chemistry, Government Rajaram College, S.U. Road, Vidyanagar, Kolhapur 416004, Maharashtra (India)

    2010-09-17

    Research highlights: {yields} CdSe thin films deposited first time by using malic acid as a complexing agent. {yields} The film samples were characterized by XRD, SEM, UV-vis-NIR spectroscopy and TEP techniques. {yields} Nanocrystalline CdSe film can be synthesized at room temperature. - Abstract: Nanocrystalline cadmium selenide thin films have been deposited on non-conducting glass substrates. The film samples were characterized by XRD, SEM, UV-vis-NIR reflection/absorption spectroscopy and TEP techniques. The annealed film samples showed a crystalline nature with a cubic crystal structure. The optical analysis showed direct band to band type of transition. The band gap of film sample was found to be in the order of 1.7 eV. The electrical conductivity of the film sample was found to be in the order of 10{sup -6} ({Omega} cm){sup -1}. TEP measurements show n-type of conductivity.

  18. Surface structure and optical property of amorphous carbon nanotubes hybridized with cadmium selenide quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Kim Han, E-mail: kimhan8419@gmail.com; Johan, Mohd Rafie [University of Malaya, Nanomaterials Engineering Research Group, Advanced Materials Research Laboratory, Department of Mechanical Engineering (Malaysia)

    2013-09-15

    Amorphous carbon nanotubes ({alpha}-CNTs) were synthesized by a chemical reaction between ferrocene and ammonium chloride at low temperature. The as-synthesized {alpha}-CNTs were then hybridized with cadmium selenide quantum dots (CdSe QDs) through a simple chemical process. Raman spectra reveal the amorphous nature of the {alpha}-CNTs surface. X-ray diffraction pattern confirmed the amorphous phase of carbon and the formation of CdSe QDs crystalline phase. Field emission scanning electron microscopy and transmission electron microscopy (TEM and HRTEM) indicate that the successfully formed hybridized {alpha}-CNTs-CdSe QDs possess an average outer diameter in the range of 110-130 nm. The CdSe QDs fall in the size range of 15-40 nm. UV-visible spectroscopy showed quantum confinement effect due to the attachment of CdSe QDs on the surface of {alpha}-CNTs.

  19. Optical and morphological characteristics of zinc selenide-zinc sulfide solid solution crystals

    Science.gov (United States)

    Singh, N. B.; Su, Ching-Hua; Arnold, Bradley; Choa, Fow-Sen

    2016-10-01

    Experiments were performed to study the effect of point defects on the optical and morphological characteristics of zinc selenide-zinc sulfide ZnSe-ZnS (ZnSexS(1-x)) solid solution crystals grown under terrestrial (1-g) condition. We used the composition ZnSe0.91S0.09 and ZnSe0.73S0.27 for the detailed studies. Crystals of 8 mm and 12 mm diameter were grown using physical vapor transport methods. These crystals did not exhibit gross defects such as voids, bubbles or precipitates. The photoluminescence spectra indicated strong red emission for the 610-630-nm wavelength region in both crystals. This emission could be explained on the basis of high energy irradiation of Zn selenide. For the ZnSe0.73S0.27 crystal, absorption starts at a lower wavelength range (300 nm) when compared to the ZnSe0.91S0.09 crystal presumably due to the much higher bandgap of ZnS than that of ZnSe. Sharp peaks at 451 and 455 nm were observed for both samples corresponding to the band edge transitions, followed by a strong peak at 632 nm. These results were consistent with the observations based on Raman spectroscopy studies. Under 532-nm laser illumination both transverse optical (TO) and longitudinal optical (LO) phonon peaks appeared at Raman shifts of 220 and 280 Δcm-1, respectively. These peaks are similar to those observed for pure ZnSe Raman spectra for which TO and LO occur at 200 and 250 Δcm-1 for the x-axis (first order) polarization.

  20. Hydrothermal synthesis of copper selenides with controllable phases and morphologies from an ionic liquid precursor

    Science.gov (United States)

    Liu, Xiaodi; Duan, Xiaochuan; Peng, Peng; Zheng, Wenjun

    2011-12-01

    Cu2-xSe nanocrystals and CuSe nanoflakes are successfully synthesized through a convenient hydrothermal method from an ionic liquid precursor 1-n-butyl-3-ethylimidazolium methylselenite ([BMIm][SeO2(OCH3)]). The phases and morphologies of the copper selenides can be controlled by simply changing the atom ratio of Cu/Se in the reactants and reaction temperature. Furthermore, it is found that the [BMIm][SeO2(OCH3)] not only serves as Se source but also has influence on the shapes of CuSe nanoflakes. The adsorption of alkyl imidazolium rings ([BMIm]+) onto the (0001) facets of covellite CuSe prohibits the growth in the [0001] direction, and CuSe nuclei growth mainly processes along the six symmetric directions (+/-[01&cmb.macr;11], +/-[101&cmb.macr;1&cmb.macr;], and +/-[1&cmb.macr;100]) to form flakelike CuSe. The obtained copper selenides are characterized by XRD, SEM, EDS, XPS, TEM, and HRTEM. The results indicate that the Cu2-xSe nanocrystals are nearly spherical particles with an average diameter of about 20 nm, the hexagonal CuSe nanoflakes are single crystals with an edge length of 100-400 nm and a thickness of 25-50 nm. The potential formation mechanism of the copper selenides is also proposed.Cu2-xSe nanocrystals and CuSe nanoflakes are successfully synthesized through a convenient hydrothermal method from an ionic liquid precursor 1-n-butyl-3-ethylimidazolium methylselenite ([BMIm][SeO2(OCH3)]). The phases and morphologies of the copper selenides can be controlled by simply changing the atom ratio of Cu/Se in the reactants and reaction temperature. Furthermore, it is found that the [BMIm][SeO2(OCH3)] not only serves as Se source but also has influence on the shapes of CuSe nanoflakes. The adsorption of alkyl imidazolium rings ([BMIm]+) onto the (0001) facets of covellite CuSe prohibits the growth in the [0001] direction, and CuSe nuclei growth mainly processes along the six symmetric directions (+/-[01&cmb.macr;11], +/-[101&cmb.macr;1&cmb.macr;], and +/-[1

  1. SESPE-FRAZIER, DIABLO, MATILIJA, DRY LAKES, SAWMILL-BADLANDS, CUYAMA, ANTIMONY, AND QUATAL ROADLESS AREAS, CALIFORNIA.

    Science.gov (United States)

    Frizzell, Virgil A.; Hale, William N.

    1984-01-01

    The study area, consisting of the Sespe-Frazier, Diablo, Matilija, Dry Lakes, Sawmill-Badlands, Cuyama, Antimony, and Quatal Roadless Areas, occupies about 872 sq mi in the Los Padres National Forest, California. Studies indicate that the Sespe-Frazier Roadless Area contains demonstrated resources of gold, gypsum, phosphate and bentonite; deposits in the Cuyama Roadless Area have demonstrated resources of gypsum; mines in the Antimony Roadless Area have demonstrated resources of antimony, gold, silver, and marble; and the Quatal Roadless Area has demonstrated resources of bentonite. The Sespe-Frazier Roadless Area has substantiated potential for geothermal resources suitable for direct-heat purposes, probable and substantiated potential for oil and gas resources, and probable potential for gold resources. Small areas of probable resource potential for antimony and gold were identified in Antimony Roadless Area.

  2. 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.

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

    International Nuclear Information System (INIS)

    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

  4. Synthesis of barium mercaptides and application of antimony/barium mercaptides

    Institute of Scientific and Technical Information of China (English)

    瞿龙; 张露露; 舒万艮

    2001-01-01

    Mercaptoacetic acid, isooctyl thioglycolate and barium hydroxide used as start materials, barium bis (2-ethylhexyl thioglycolate) (Ba(2EHTG)2), barium thioglycolate (Ba(TG)) and barium bisthioglycolate (Ba(TG)2) were synthesized. Their optimum synthetic techniques were discussed, and some physicochemical data were reported. Infrared spectroscopy and elemental analysis methods were used to identify the structures. They were put into PVC plastic products together with antimony tris (2-ethylhexyl thioglycolate) (Sb(2EHTG)3) under the suitable compounding, and their heat stability to PVC was studied. It is shown that these barium mercaptides have remarkable synergisms with antimony mercaptides and the long-term stabilizing effect of organoantimony stabilizer can be effectively improved, reducing the amount of antimony compounds so as to avoid the decrease of its stabilizing effect.

  5. Response of cutaneous leishmaniasis (chiclero's ulcer) to treatment with meglumine antimoniate in Southeast Mexico.

    Science.gov (United States)

    Vargas-Gonzalez, A; Canto-Lara, S B; Damian-Centeno, A G; Andrade-Narvaez, F J

    1999-12-01

    Cutaneous leishmaniasis, known as chiclero's ulcer in southeastern Mexico, is characterized by a predominantly single, painless, ulcerated lesion, without lymphangitis or adenopathy. When located on the ear, it tends to become chronic, causing destruction of the pinna and disfigurement. It is caused predominantly by Leishmania (L.) mexicana. Although pentavalent antimonials (Sb5+) are the mainstay of leishmanial therapy and have been used for more than 50 years, dosage regimens have been repeatedly modified and the best one has not been fully identified. The main purpose of the present study was to investigate the response of chiclero's ulcer to treatment with meglumine antimoniate. One hundred five patients were treated with meglumine antimoniate at a daily dose of 1 ampule per day (425 mg of Sb5+) until healing. The lesions healed after a mean of 25 days (range = 5-60 days). PMID:10674678

  6. Geothermal and fluid flowing simulation of ore-forming antimony deposits in Xikuangshan

    Institute of Scientific and Technical Information of China (English)

    YANG Ruiyan; MA Dongsheng; BAO Zhengyu; PAN Jiayong; CAO Shuanglin; XIA Fei

    2006-01-01

    The Xikuangshan Antimony Deposit located in the Mid-Hunan Basin, China, is the largest antimony deposit in the world. Based on the hydrogeological and geochemical data collected from four sections, Xikuangshan-Dajienao (AO), Xikuangshan-Dashengshan (BO), Xikuangshan-Longshan (CO) and Dafengshan (DO) in the Basin, an advanced metallogenic model related to deep-cyclic meteoric water of Xikuangshan Antimony Deposit is put forward in this paper using a model of heat-gravity-driving fluid flow transportation. The simulation results show that the ore-forming fluid of the deposit mainly comes from the Dashengshan and Longshan areas where BO and CO sections are located if the overall basin keeps a constant atmospheric precipitation and infiltration rate during mineralization, and that the average transportation speed of the ore-forming fluids is about 0.2-0.4 m/a.

  7. 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.

  8. Future trends of global atmospheric antimony emissions from anthropogenic activities until 2050

    Science.gov (United States)

    Zhou, Junrui; Tian, Hezhong; Zhu, Chuanyong; Hao, Jiming; Gao, Jiajia; Wang, Yong; Xue, Yifeng; Hua, Shenbin; Wang, Kun

    2015-11-01

    This paper presents the scenario forecast of global atmospheric antimony (Sb) emissions from anthropogenic activities till 2050. The projection scenarios are built based on the comprehensive global antimony emission inventory for the period 1995-2010 which is reported in our previous study. Three scenarios are set up to investigate the future changes of global antimony emissions as well as their source and region contribution characteristics. Trends of activity levels specified as 5 primary source categories are projected by combining the historical trend extrapolation with EIA International energy outlook 2013, while the source-specific dynamic emission factors are determined by applying transformed normal distribution functions. If no major changes in the efficiency of emission control are introduced and keep current air quality legislations (Current Legislation scenario), global antimony emissions will increase by a factor of 2 between 2010 and 2050. The largest increase in Sb emissions is projected from Asia due to large volume of nonferrous metals production and waste incineration. In case of enforcing the pollutant emission standards (Strengthened Control scenario), global antimony emissions in 2050 will stabilize with that of 2010. Moreover, we can anticipate further declines in Sb emissions for all continents with the best emission control performances (Maximum Feasible Technological Reduction scenario). Future antimony emissions from the top 10 largest emitting countries have also been calculated and source category contributions of increasing emissions of these countries present significant diversity. Furthermore, global emission projections in 2050 are distributed within a 1° × 1°latitude/longitude grid. East Asia, Western Europe and North America present remarkable differences in emission intensity under the three scenarios, which implies that source-and-country specific control measures are necessary to be implemented for abating Sb emissions from

  9. Studies on Thin Films of Antimony Vacuum Evaporated from a Knudsen-Type Source

    Directory of Open Access Journals (Sweden)

    K.L. Chaudhary

    2000-10-01

    Full Text Available A Knudsen-type evaporation source was used for the deposition of thin films of antimony to study their growth and microstructure under different rates of evaporation and substrate temperatures when vacuum evaporated onto air-cleaved KC1, mica, amorphous carbon and doped KCl substrates. The crystallisation of these films on exposure to an electron beam of moderate intensity inside the electron microscope was studied, and the orientations of the crystallised films wrt the substrate were established. It has been concluded that antimony films prepared by this source compare well with those prepared by other sources of vacuum evaporation.

  10. 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.

  11. SIMS study of effect of Cr adhesion layer on the thermal stability of silver selenide thin films on Si

    International Nuclear Information System (INIS)

    Effect of heat treatment on silver selenide films grown from diffusion-reaction of Ag and Se films on Cr-buffered Si substrates was investigated up to 400 deg. C. X-ray diffraction (XRD), Scanning electron microscopy (SEM), Secondary ion mass spectrometry (SIMS) and X-ray photoelectron spectroscopy (XPS) were used to characterize the films. XRD patterns of the films showed stress assisted change in preferential orientation of the films upon annealing: the films annealed at 200 deg. C exhibited a strong orientation along (2 0 0) plane, which changed to (0 1 3) after annealing at 300 and 400 deg. C. Dynamic SIMS measurements showed that Cr is confined to the interface and that there is no diffusion of Cr into silver selenide

  12. Fluorescence imaging technology (FI) for high-throughput screening of selenide-modified nano-TiO2 catalysts.

    Science.gov (United States)

    Wang, Liping; Lee, Jianchao; Zhang, Meijuan; Duan, Qiannan; Zhang, Jiarui; Qi, Hailang

    2016-02-18

    A high-throughput screening (HTS) method based on fluorescence imaging (FI) was implemented to evaluate the catalytic performance of selenide-modified nano-TiO2. Chemical ink-jet printing (IJP) technology was reformed to fabricate a catalyst library comprising 1405 (Ni(a)Cu(b)Cd(c)Ce(d)In(e)Y(f))Se(x)/TiO2 (M6Se/Ti) composite photocatalysts. Nineteen M6Se/Tis were screened out from the 1405 candidates efficiently.

  13. Reduced Species(HSO-2,SO·-2)Promoted One-Pot Efficient Synthesis of Phenyl Alkyl Selenides

    Institute of Scientific and Technical Information of China (English)

    TANG,Ri-Yuan; ZHONG,Ping; LIN,Qiu-Lian

    2007-01-01

    Reduced species(HSO-2,SO·-2)promoted one-pot synthesis of phenyl alkyl selenides has been developed.This synthetic method was achieved by reactions of diphenyl diselenide with alkyl halides at room temperature.It is noteworthy that the reactions were operated under mild reaction conditions,required short time,and got good resuits.A single electron transfer reaction mechanism was proposed for the reaction.

  14. The Short Series of the Oxygen-Poor Lanthanide Oxide Selenides M10OSe14 with M = La–Nd

    Directory of Open Access Journals (Sweden)

    Frank A. Weber

    2012-08-01

    Full Text Available Single crystals and phase pure samples of oxygen-poor ternary lanthanide oxide selenides with the composition M10OSe14 (M = La–Nd; tetragonal, I41/acd; a = 1592.0–1559.8 pm, c = 2106.5–2062.9 pm could be obtained by reacting the corresponding metals, selenium and selenium dioxide as oxygen source. Their crystal structures are isotypic with Pr10OS14 and thus contain isolated [OM4]10+ tetrahedra (d(O2––M3+ = 243–248 pm embedded in a complex anionic {[M6Se14]10–} lanthanide selenide matrix (d(M3+–Se2– = 288–358 pm. All three crystallographically independent M3+ cations exhibit eight contacts to chalcogenide anions (O2– and/or Se2– resulting in the formation of bicapped trigonal prismatic coordination polyhedra. The optical band gaps of the oxide selenides M10OSe14 amount to values between 1.89 and 2.04 eV indicating wide band-gap semiconductors.

  15. 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.

  16. Commerce Ministry Announced the Export Quotas for Zinc,Antimony,Tungsten,Tin and Silver

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    <正> The Ministry of Commerce recently announcedits decision on the export quotas for zinc,anti-mony,tungsten,tin and silver in 2004.Accord-ing to the data released,all the export quotasare reduced except for silver.Relevant peoplesay that the raw materials shortage is a majorissue for the production of antimony and tin,

  17. Determination of barium and antimony in gun shot residues by neutron activation analysis

    International Nuclear Information System (INIS)

    The antimony contents on both hands of 7 persons before and after firing an automatic pistol were determined by instrumental neutron activation analysis. The gun shot residues were removed from hands by a 4% solution of cellulose acetate in acetone. The average content of antimony on both hands before firing obtained from 70 measurements (35 from each hand) was 0.040 ± 0.010 micro gram, whereas the average contents on the right and the left hands after 1 firing were 0.385 ± 0.036 and 0.144 ± 0.029 micro gram respectively. The ration of the antimony contents after 1 firing to the normal level (before firing) was 9.9 for the right and 3.6 for the left. No significant difference was observed between male and female, smoker and non-smoker. The antimony content after several firings was not much different from that of 1 firing and it reduced to the normal level within 2 days after firing. The barium contents before and after firing were studied from one person. Barium was precipitated as Ba SO4 before counting. An average contents of 0.936 ± 0.551 micro gram for both hands before firing, 4.092 ± 2.687 micro gram for the right hand and 1.363 ± 0.879 micro gram for the left hand after 1 firing were found

  18. Investigation on the thermal radiation properties of antimony doped tin oxide particles

    Institute of Scientific and Technical Information of China (English)

    Fu Cheng-Wu; Zhang Shuan-Qin; Chen Ming-Qing

    2008-01-01

    This paper reports the preparation of antimony doped tin oxide crystalline powders by chemical coprecipitation method. The influence of sintering temperature and the sintering retention time on the thermal infrared emissivity is analysed. The thermal infrared reflectivity is measured and the optimum doping concentration is proposed.

  19. Thermodynamics for arsenic and antimony in copper matte converting—computer simulation

    Science.gov (United States)

    Chaubal, P. C.; Nagamori, M.

    1988-08-01

    Thermodynamic data for arsenic and antimony and their sulfide and oxide gases have been critically reviewed and compiled. The entropy values for AsS(g), SbS(g), and BiS(g) have been recalculated based on a statistical thermodynamic method. The standard heat of formation and entropy of As2O3(g) have been newly assessed to be △H{298/0} = -81,500 cal/mole and S{298/0} = 81.5 cal/deg/mole. Copper matte converting has been mathematically described using the stepwise equilibrium simulation technique together with quadratic approximations of oxygen and magnetite solubilities in molten mattes. A differential equation for the volatilization of arsenic and antimony has been derived and solved for successive reaction microsteps, whereby the volatilization, slagging, and alloying of the minor elements in copper matte converting have been examined as functions of reaction time and other process variables. Only the first (slag-making) stage of converting is responsible for the elimination of arsenic and antimony by volatilization. Arsenic volatilizes mainly as AsS(g) and AsO(g), with As2(g) also contributing when initial mattes are unusually rich in arsenic (above 0.5 pct arsenic). Antimony volatilizes chiefly as SbS(g), and the contributions of other gases such as SbO(g) and Sb(g) always remain negligibly low. The results of the stepwise equilibrium simulation compare favorably with the industrial operating data.

  20. Synthesis of antimony tris(mercaptoethyl carboxylates) as thermal stabilizer for polyvinyl chloride

    Institute of Scientific and Technical Information of China (English)

    舒万艮; 刘又年; 陈启元

    2002-01-01

    A novel type of thermal stabilizers-antimony tris(mercaptoethyl carboxylates) (Sb(SCH2CH2OOCR) 3), was synthesized from carboxylic acid, antimony trioxide and 2-mercaptoethanol in two steps. The experimental results show that the molar ratio of carboxylic acid to antimony tris(2-hydroxyethyl mercaptide) is 1.2, when adding 0.6% tetra-n-butyl titanate as catalyst and xylene as isotropic solvent, heating and refluxing for about 2~4h. The thermal stability was measured by heat-aging oven test. The thermal stability time is about 8~40min(at 200℃) when adding 2% tetra-n-butyl titanate in polyvinyl chloride(PVC). Among these stabilizers, antimony tris(mercaptoethyl stearate) has best thermal stability. Its thermal stability is better than that of Ca-Zn complex and basic lead stabilizers, and equal to that of organotin. In addition, the stabilization mechanism of this kind of stabilizers for PVC was discussed briefly.

  1. Antimony production by carbothermic reduction of stibnite in the presence of lime

    Directory of Open Access Journals (Sweden)

    Padilla R.

    2014-01-01

    Full Text Available Experimental work on the carbothermic reduction of Sb2S3 in the presence of lime was carried out in the temperature range of 973 to 1123 K to produce antimony in an environmentally friendly manner. The results demonstrated the technical feasibility of producing antimony by this method without producing SO2 gas. Complete conversion of Sb2S3 was obtained at 1023 K in about 1000 seconds and at 1123 K in less than 250 seconds using stibnite-carbon-lime mixtures with molar ratios Sb2S3:CaO:C = 1:3:3. It was found that the reduction proceeds through the formation of an intermediate oxide SbO2, which is subsequently reduced by CO(g to yield antimony metal and CaS. The kinetics of the Sb2S3 reduction was analyzed by using the equation ln(1-X = -kt. The activation energy was 233 kJ mol-1 in the temperature range of 973 to 1123 K. This value would correspond to an antimony catalyzed carbon oxidation by CO2.

  2. Antimonial drugs entrapped into phosphatidylserine liposomes: physicochemical evaluation and antileishmanial activity

    Directory of Open Access Journals (Sweden)

    Samanta Etel Treiger Borborema

    2016-04-01

    Full Text Available Abstract: INTRODUCTION: Leishmaniasis is a disease caused by the protozoan Leishmania that resides mainly in mononuclear phagocytic system tissues. Pentavalent antimonials are the main treatment option, although these drugs have toxic side effects and high resistance rates. A potentially alternative and more effective therapeutic strategy is to use liposomes as carriers of the antileishmanial agents. The aims of this study were to develop antimonial drugs entrapped into phosphatidylserine liposomes and to analyze their biological and physicochemical characteristics. METHODS: Liposomes containing meglumine antimoniate (MA or pentavalent antimony salt (Sb were obtained through filter extrusion (FEL and characterized by transmission electron microscopy. Promastigotes of Leishmania infantum were incubated with the drugs and the viability was determined with a tetrazolium dye (MTT assay. The effects of these drugs against intracellular amastigotes were also evaluated by optical microscopy, and mammalian cytotoxicity was determined by an MTT assay. RESULTS: Liposomes had an average diameter of 162nm. MA-FEL showed inhibitory activity against intracellular L. infantum amastigotes, with a 50% inhibitory concentration (IC50 of 0.9μg/mL, whereas that of MA was 60μg/mL. Sb-FEL showed an IC50 value of 0.2μg/mL, whereas that of free Sb was 9μg/mL. MA-FEL and Sb-FEL had strong in vitro activity that was 63-fold and 39-fold more effective than their respective free drugs. MA-FEL tested at a ten-times higher concentration than Sb-FEL did not show cytotoxicity to mammalian cells, resulting in a higher selectivity index. CONCLUSIONS: Antimonial drug-containing liposomes are more effective against Leishmania-infected macrophages than the non-liposomal drugs.

  3. Layered bismuth selenide utilized as hole transporting layer for highly stable organic photovoltaics

    KAUST Repository

    Yuan, Zhongcheng

    2015-11-01

    Abstract Layered bismuth selenide (L-Bi2Se3) nanoplates were implemented as hole transporting layers (HTLs) for inverted organic solar cells. Device based on L-Bi2Se3 showed increasing power conversion efficiency (PCE) during ambient condition storage process. A PCE of 4.37% was finally obtained after 5 days storage, which outperformed the ones with evaporated-MoO3 using poly(3-hexylthiophene) (P3HT) as donor material and [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM) as acceptor. The improved device efficiency can be attributed to the high conductivity and increasing work function of L-Bi2Se3. The work function of L-Bi2Se3 increased with the storage time in ambient condition due to the oxygen atom doping. Ultraviolet photoelectron spectroscopy and high resolution X-ray photoelectron spectroscopy were conducted to verify the increased work function, which originated from the p-type doping process. The device based on L-Bi2Se3 exhibited excellent stability in ambient condition up to 4 months, which was much improved compared to the device based on traditional HTLs. © 2015 Elsevier B.V.

  4. Synthesis of Co-Electrospun Lead Selenide Nanostructures within Anatase Titania Nanotubes for Advanced Photovoltaics

    Directory of Open Access Journals (Sweden)

    Evan K. Wujcik

    2015-06-01

    Full Text Available Inorganic nano-scale heterostructures have many advantages over hybrid organic-inorganic dye-sensitized solar cells (DSSC or Grätzel cells, including their resistance to photo-bleaching, thermal stability, large specific surface areas, and general robustness. This study presents a first-of-its-kind low-cost all-inorganic lead selenide-anatase titania (PbSe/TiO2 nanotube heterostructure material for photovoltaic applications. Herein, PbSe nanostructures have been co-electrospun within a hollow TiO2 nanotube with high connectivity for highly efficient charge carrier flow and electron-hole pair separation. This material has been characterized by transmission electron microscopy (TEM, electron diffraction, energy dispersive X-ray spectroscopy (EDX to show the morphology and material composition of the synthesized nanocomposite. Photovoltaic characterization has shown this newly synthesized proof-of-concept material can easily produce a photocurrent under solar illumination, and, with further refinement, could reveal a new direction in photovoltaic materials.

  5. New route for preparation of luminescent mercaptoethanoate capped cadmium selenide quantum dots

    Indian Academy of Sciences (India)

    Manoj E Wankhede; Shaukatali N Inamdar; Aparna Deshpande; Aniket R Thete; Renu Pasricha; Sulabha K Kulkarni; Santosh K Haram

    2008-06-01

    We report a synthesis of cadmium selenide quantum dots (Q-CdSe) by refluxing a mixture of cadmium acetate, selenium powder, sodium sulfite and 2-mercaptoethanol in N,N′-dimethyl formamide (DMF)/water solution. X-ray and electron diffractions suggest the formation of hexagonal phase of size quantized CdSe. Based on TEM analysis, the formation of nanoparticles with an average diameter of 3.5 ± 0.5 nm is inferred. Their sols in DMF and dimethyl sulphoxide (DMSO) gave characteristic absorption peaks at 300 nm and 327 nm, which is attributed to the formation of high quality, size quantized CdSe particles. Extracted particles from the sol were readily redispersed in DMF and DMSO, which were diluted further with water without losing their optical and colloidal properties. FTIR spectroscopy suggested the formation of 2-mercaptoethanol thiolate on the particle surface, with free –OH groups available for linkage. Sols in DMSO and their solutions in water displayed an intense photoluminescence (PL).

  6. Femtosecond Transient Absorption Studies in Cadmium Selenide Nanocrystal Thin Films Prepared by Chemical Bath Deposition Method

    Directory of Open Access Journals (Sweden)

    M. C. Rath

    2007-01-01

    Full Text Available Dynamics of photo-excited carrier relaxation processes in cadmium selenide nanocrystal thin films prepared by chemical bath deposition method have been studied by nondegenerate femtosecond transient pump-probe spectroscopy. The carriers were generated by exciting at 400 nm laser light and monitored by several other wavelengths. The induced absorption followed by a fast bleach recovery observed near and above the bandgap indicates that the photo-excited carriers (electrons are first trapped by the available traps and then the trapped electrons absorb the probe light to show a delayed absorption process. The transient decay kinetics was found to be multiexponential in nature. The short time constant, <1 picosecond, was attributed to the trapping of electrons by the surface and/or deep traps and the long time constant, ≥20 picoseconds, was due to the recombination of the trapped carriers. A very little difference in the relaxation processes was observed in the samples prepared at bath temperatures from 25∘C to 60∘C.

  7. Noncentrosymmetric selenide Ba4Ga4GeSe12: Synthesis, structure, and optical properties

    Science.gov (United States)

    Yin, Wenlong; Iyer, Abishek K.; Li, Chao; Lin, Xinsong; Yao, Jiyong; Mar, Arthur

    2016-09-01

    The selenide Ba4Ga4GeSe12, synthesized by reaction of BaSe, Ga2Se3, and GeSe2 at 1173 K, adopts a noncentrosymmetric tetragonal structure (space group P 4 bar21 c , Z=2, a=13.5468(4) Å, c=6.4915(2) Å) consisting of a three-dimensional network built from two types of corner-sharing MSe4 tetrahedra, with Ba cations occupying the intervening voids. It is isostructural to Pb4Ga4GeS12, Pb4Ga4GeSe12, and Ba4Ga4SnSe12, but differs subtly in site ordering. Structural refinements and bond valence sum analysis suggest partial disorder manifested by mixing of 0.75 Ga and 0.25 Ge within one tetrahedral site, and occupation of exclusively Ga within the other tetrahedral site. The optical band gap of 2.18(2) eV, measured from the UV/VIS/NIR diffuse reflectance spectrum, agrees with a calculated gap of 2.35 eV between valence and conduction bands and is consistent with the orange-yellow color of the crystals. Nonlinear optical measurements on powder samples revealed a weak second harmonic generation signal using 2.09 μm as the fundamental laser wavelength.

  8. Light-emitting diodes made from cadmium selenide nanocrystals and a semiconducting polymer

    Science.gov (United States)

    Colvin, V. L.; Schlamp, M. C.; Alivisatos, A. P.

    1994-08-01

    ELECTROLUMINESCENT devices have been developed recently that are based on new materials such as porous silicon1 and semiconducting polymers2,3. By taking advantage of developments in the preparation and characterization of direct-gap semiconductor nanocrystals4-6, and of electroluminescent polymers7, we have now constructed a hybrid organic/inorganic electroluminescent device. Light emission arises from the recombination of holes injected into a layer of semiconducting p-paraphenylene vinylene (PPV)8-10 with electrons injected into a multilayer film of cadmium selenide nanocrystals. Close matching of the emitting layer of nanocrystals with the work function of the metal contact leads to an operating voltage11 of only 4V. At low voltages emission from the CdSe layer occurs. Because of the quantum size effect19-24 the colour of this emission can be varied from red to yellow by changing the nanocrystal size. At higher voltages green emission from the polymer layer predominates. Thus this device has a degree of voltage tunability of colour.

  9. Development of new layered selenide oxides with perovskite-type oxide layers

    Science.gov (United States)

    Ushiyama, Koichi; Ogino, Hiraku; Kishio, Kohji; Shimoyama, Jun-Ichi

    2010-03-01

    Several Fe-based superconductors with perovskite-type oxide layers, such as Sr2ScFePO3 (Tc ˜ 17 K)^[1], were discovered in our previous study. These compounds are composed of alternate stacking of superconducting layers with antifluorite structure and perovskite-type blocking layers. Since both layers are flexible in terms of chemical composition, development of various new functional materials can be expected from this family. In the present study, we have attempted to synthesize new layered selenide oxides with CuSe layers and discovered more than ten compounds, such as Sr2MCu2Se2O2 (M = Mn, Co, Ni, Cu, Zn) and Sr2MCuSeO3 (M = Sc, Cr, Mn, Fe, Ga, In), thus far. These indicated that the CuSe layer can accommodate various types of blocking layers, which may lead various functions. Among them, Sr2Cu3Se2O2 has a potential as for the mother compound of superconductor, if appropriate concentration of carrier is introduced to the CuO2 layer. Crystal structure and physical properties of these newly found compounds will be reported. [1] H. Ogino et al., Supercond. Sci. Technol. 22 (2009) 075008

  10. Influence of different deposition potential on the structural and optical properties of copper selenide nanowires

    Science.gov (United States)

    Kaur, Harmanmeet; Kaur, Jaskiran; Singh, Lakhwant

    2016-09-01

    In this paper, nanowires were successfully fabricated from the aqueous solution containing 0.2 M/l CuSO4.5H2O, 0.1 M/l SeO2, 1 g/l PVP and a few drops of H2SO4 in Milli-Q water using electrodeposition technique at room temperature. Influence of different deposition potential on structural and optical properties of copper selenide nanowires has been investigated here. Morphological, structural and optical properties were monitored through field emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD) and UV-visible 1800 spectrophotometer. From the XRD analysis, it was found that the stoichiometric (CuSe) nanowires are formed at deposition potential (-0.6 V) and (+0.6 V). Band gap of nanowires were found to be maximum around 3.13 eV for deposition potential (-0.8 V) and minimum of 2.81 eV for deposition potential (-0.6 V).

  11. Highly efficient copper-zinc-tin-selenide (CZTSe) solar cells by electrodeposition.

    Science.gov (United States)

    Jeon, Jong-Ok; Lee, Kee Doo; Seul Oh, Lee; Seo, Se-Won; Lee, Doh-Kwon; Kim, Honggon; Jeong, Jeung-hyun; Ko, Min Jae; Kim, BongSoo; Son, Hae Jung; Kim, Jin Young

    2014-04-01

    Highly efficient copper-zinc-tin-selenide (Cu2ZnSnSe4 ; CZTSe) thin-film solar cells are prepared via the electrodepostion technique. A metallic alloy precursor (CZT) film with a Cu-poor, Zn-rich composition is directly deposited from a single aqueous bath under a constant current, and the precursor film is converted to CZTSe by annealing under a Se atmosphere at temperatures ranging from 400 °C to 600 °C. The crystallization of CZTSe starts at 400 °C and is completed at 500 °C, while crystal growth continues at higher temperatures. Owing to compromises between enhanced crystallinity and poor physical properties, CZTSe thin films annealed at 550 °C exhibit the best and most-stable device performances, reaching up to 8.0 % active efficiency; among the highest efficiencies for CZTSe thin-film solar cells prepared by electrodeposition. Further analysis of the electronic properties and a comparison with another state-of-the-art device prepared from a hydrazine-based solution, suggests that the conversion efficiency can be further improved by optimizing parameters such as film thickness, antireflection coating, MoSe2 formation, and p-n junction properties. PMID:24692285

  12. Electrodes modified with bismuth, antimony and tin precursor compounds for electrochemical stripping analysis of trace metals (a short review)

    OpenAIRE

    Lezi, Nikolitsa; Economou, Anastasios; Barek, Jiří

    2014-01-01

    Over the last decade, intensive research is being carried out towards the development of “green” electrochemical sensors. Bismuth, antimony and tin electrodes have been proposed as potential substitutes of mercury electrodes in electrochemical stripping analysis of trace metals. The main advantage of these metals as electrode materials is their lower toxicity compared to mercury. Among the different configuration of bismuth, antimony and tin electrodes, one of the most attractive inv...

  13. Investigation into properties of the mixture of perfluoro-2-methyl-bicyclo(4,4,0) decane with antimony fluoride

    International Nuclear Information System (INIS)

    State diagram was constructed for a binary system formed by antimony fluoride and perfluoro-2-methyl-bicyclo-(4,4,0)decane in the temperature range of -58 deg to +56 deg C. Temperature dependence of solubility and the differential molar heat of solubility of solid Sb F5 were determined. Above the melting point of antimony fluoride these components were found to form a system of two sparingly miscible liquids with upper critical dissolution temperature

  14. Electrodeposition of SnSbCu Alloy on Copper from an Electrolyte with Varied Content of Antimony Chloride

    Science.gov (United States)

    Valeeva, A. Kh.; Valeev, I. Sh.

    2015-10-01

    The microstructure and chemical composition of electrodeposited alloys of the SnSbCu system with varied concentration of antimony chloride in the electrolyte have been investigated. It is shown that during electrodeposition mechanical-mixture alloys are not formed, but rather intermetallic compounds. It is found that increasing the concentration of antimony chloride in the electrolyte leads to a decrease in the tin content and cracking of the coating.

  15. The Ministry of Land and Resources Continued to Impose Total Exploitation Control on Tungsten, Antimony and Rare Earth

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    <正>The General Office of the Ministry of Land and Resources distributed "Notice on Issuing Total Exploitation Control Quota of Tungsten Mine, Antimony Mine and Rare Earth Mine (First Batch) for 2013" (the "Notice") on January 5, it issued total exploitation control quota of tungsten mine, antimony mine and rare earth mine (first batch) for 2013. According to the Notice, the first batch of national

  16. 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.

  17. Development of high-efficiency solar cells on copper indium selenide single crystals (cadmium sulfide, zinc oxide)

    Energy Technology Data Exchange (ETDEWEB)

    Yip, Lap Sum

    1996-12-31

    Photovoltaic cells with a ZnO/CdS/CuInSe{sub 2} structure were fabricated on bulk CuInSe{sub 2} substrates. Conversion efficiencies of more than or near 10 per cent were obtained on cells with an active area and without the use of antireflection coating. Copper indium selenide single crystals can be used as absorbers in thin film solar cells. In this study, the single crystals were grown by a horizontal Bridgman method. An annealing of the CuInSe{sub 2} substrate before the CdS deposition was found to be essential in obtaining high photovoltaic performance.

  18. The Non-Isotypical Nitride Selenides Dy3NSe3 and Ho3NSe3: Chains and Dimers

    OpenAIRE

    Lissner, Falk; Schleid, Thomas

    2009-01-01

    Abstract The non-isotypical lanthanoid(III) nitride selenides M3NSe3 of dysprosium (Dy3NSe3) and holmium (Ho3NSe3) are formed by the reaction of the respective rare-earth metal (M = Dy and Ho) with sodium azide (NaN3), selenium and an excess of iodine at 900 ?C from torch-sealed evacuated silica ampoules within seven days. Dy3NSe3 crystallizes orthorhombically (a = 1245.38(9), b = 393.69(3), c = 1303.74(9) pm) in space group Pnma with Z = 4, whereas monoclinic Ho3NSe3 (a = 1152.93(...

  19. NaBH{sub 4}/[bmim]BF{sub 4}: a new reducing system to access vinyl selenides and tellurides

    Energy Technology Data Exchange (ETDEWEB)

    Lenardao, Eder J.; Goncalves, Loren C.C.; Mendes, Samuel R.; Saraiva, Maiara T.; Alves, Diego; Jacob, Raquel G.; Perin, Gelson, E-mail: lenardao@ufpel.edu.b [Universidade Federal de Pelotas (UFPel), RS (Brazil). Inst. de Quimica e Geociencias. Lab. de Sintese Organica Limpa (LASOL)

    2010-07-01

    A general and simple method for the synthesis of vinyl selenides and tellurides starting from terminal alkynes and diorganyl chalcogenides using NaBH{sub 4} and [bmim]BF{sub 4} as a recyclable solvent was developed. This efficient and improved method furnishes the corresponding vinyl chalcogenides preferentially with Z configuration. We also observed that when the same protocol was applied to phenyl acetylene, (E)-bis-phenylchalcogeno styrenes were obtained in good yields and high selectivity. The ionic liquid was reused up three times without lost of efficiency. (author)

  20. Parallel molecular dynamics simulations of pressure-induced structural transformations in cadmium selenide nanocrystals

    Science.gov (United States)

    Lee, Nicholas Jabari Ouma

    Parallel molecular dynamics (MD) simulations are performed to investigate pressure-induced solid-to-solid structural phase transformations in cadmium selenide (CdSe) nanorods. The effects of the size and shape of nanorods on different aspects of structural phase transformations are studied. Simulations are based on interatomic potentials validated extensively by experiments. Simulations range from 105 to 106 atoms. These simulations are enabled by highly scalable algorithms executed on massively parallel Beowulf computing architectures. Pressure-induced structural transformations are studied using a hydrostatic pressure medium simulated by atoms interacting via Lennard-Jones potential. Four single-crystal CdSe nanorods, each 44A in diameter but varying in length, in the range between 44A and 600A, are studied independently in two sets of simulations. The first simulation is the downstroke simulation, where each rod is embedded in the pressure medium and subjected to increasing pressure during which it undergoes a forward transformation from a 4-fold coordinated wurtzite (WZ) crystal structure to a 6-fold coordinated rocksalt (RS) crystal structure. In the second so-called upstroke simulation, the pressure on the rods is decreased and a reverse transformation from 6-fold RS to a 4-fold coordinated phase is observed. The transformation pressure in the forward transformation depends on the nanorod size, with longer rods transforming at lower pressures close to the bulk transformation pressure. Spatially-resolved structural analyses, including pair-distributions, atomic-coordinations and bond-angle distributions, indicate nucleation begins at the surface of nanorods and spreads inward. The transformation results in a single RS domain, in agreement with experiments. The microscopic mechanism for transformation is observed to be the same as for bulk CdSe. A nanorod size dependency is also found in reverse structural transformations, with longer nanorods transforming more

  1. Analysis on the Performance of Copper Indium Gallium Selenide (CIGS Based Photovoltaic Thermal

    Directory of Open Access Journals (Sweden)

    Zulkepli Afzam

    2016-01-01

    Full Text Available This paper deals with the efficiency improvement of Copper Indium Gallium Selenide (CIGS Photovoltaic (PV and also solar thermal collector. Photovoltaic thermal (PV/T can improve overall efficiency for PV and also solve the problem of limited roof space at urban area. Objective of this study is to clarify the effect of mass flow rate on the efficiency of the PV/T system. A CIGS solar cell is used with rated output power 65 W and 1.18 m2 of area. 4 set of experiments were carried out, which were: thermal collector with 0.12 kg/s flow rate, PV/T with 0.12 kg/s flow rate, PV/T with 0.09 kg/s flow rate and PV. It was found that PV/T with 0.12 kg/s flow rate had the highest electrical efficiency, 2.92 %. PV/T with 0.09 kg/s flow rate had the lowest electrical efficiency, 2.68 %. It also had 2 % higher overall efficiency. The efficiency gained is low due to several factors. The rated output power of the PV is low for the area of 1.18 m2. The packing factor of the PV also need to be considered as it may not be operated at the optimal packing factor. Furthermore, aluminium sheet of the PV may affect the PV temperature due to high thermal conductivity. Further study on more values of mass flow rate and also other parameters that affect the efficiency of the PV/T is necessary.

  2. Transparent nickel selenide used as counter electrode in high efficient dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Jinbiao; Wu, Jihuai, E-mail: jhwu@hqu.edu.cn; Tu, Yongguang; Huo, Jinghao; Zheng, Min; Lin, Jianming

    2015-08-15

    Highlights: • A transparent Ni{sub 0.85}Se is prepared by a facile solvothermal reaction. • Ni{sub 0.85}Se electrode has better electrocatalytic activity than Pt electrode. • DSSC with Ni{sub 0.85}Se electrode obtains efficiency of 8.88%, higher than DSSC with Pt. • DSSC with Ni{sub 0.85}Se/mirror electrode achieves an efficiency of 10.19%. - Abstract: A transparent nickel selenide (Ni{sub 0.85}Se) is prepared by a facile solvothermal reaction and used as an efficient Pt-free counter electrode (CE) for dye-sensitized solar cells (DSSCs). Field emission scanning electron microscopy observes that the as-prepared Ni{sub 0.85}Se possesses porous structure. Cyclic voltammogram measurement indicates that Ni{sub 0.85}Se electrode has larger current density than Pt electrode. Electrochemical impedance spectroscopy shows that the Ni{sub 0.85}Se electrode has lower charge-transfer resistance than Pt electrode. Under simulated solar light irradiation with intensity of 100 mW cm{sup −2} (AM 1.5), the DSSC based on the Ni{sub 0.85}Se CE achieves a power conversion efficiency (PCE) of 8.88%, which is higher than the solar cell based on Pt CE (8.13%). Based on the transparency of Ni{sub 0.85}Se, the DSSC with Ni{sub 0.85}Se/mirror achieves a PCE of 10.19%.

  3. Exploring the doping effects of copper on thermoelectric properties of lead selenide

    Science.gov (United States)

    Gayner, Chhatrasal; Sharma, Raghunandan; Mallik, Iram; Das, Malay K.; Kar, Kamal K.

    2016-07-01

    In this work, we have explored the effect of dopant concentration (copper (Cu)) on the thermoelectric performance of Cu doped lead selenide (Pb1-x Cu x Se (0  ⩽  x  ⩽  0.1)). With increasing the dopant concentration, sign inversion of majority charge carriers takes place for x  ⩾  0.04 due to the donor behaviour of Cu in the P-type pristine PbSe. The room temperature Seebeck coefficients of Pb1-x Cu x Se with x  =  0.01, 0.02, 0.04, 0.06 and 0.08 are observed to be 233, 337, -473.7, -392.5 and  -257.6 μV K-1, respectively as compared to that of 186.4 μV K-1 of the pristine PbSe. This increment in Seebeck coefficient is the result of low carrier concentration and is not related to the resonance states created by Cu dopant. At room temperature, the lattice thermal conductivity of pristine PbSe is 0.52 W m-1 K-1 while for Cu doped PbSe, it varies from 0.8 to 1.1 W m-1 K-1. Finally, with ZT of ~0.59 and power factor of ~700 at 500 K, Pb0.98Cu0.02Se exhibits the highest thermoelectric performance among the studied Pb1-x Cu x Se systems. Owing to the high ZT and power factor, a single thermoelement of Pb0.98Cu0.02Se exhibits thermovoltage of  >100 mV at a temperature gradient of 200 °C.

  4. [Physico-chemical characteristics of meglumine antimoniate in different storage conditions].

    Science.gov (United States)

    Romero, G A; de Oliveira, M R; Correia, D; Marsden, P D

    1996-01-01

    During the period October 1992 to July 1995 we measured the osmolarity and pH of ampoules of meglumine antimoniate (glucantime) from lot 9206L-004 (manufactured by Rhodia Farma Ltd, of São Paulo, SP, Brazil) maintained in three temperature conditions namely 4 degrees C, 37 degrees C and ambiental. Although we observed statistically significant differences in osmolarity between samples, the limited number of measurements and the variation of this property in ampoules maintained at the same temperature were obstacles to obtain definitive conclusions. Such a variation was not found with pH. Assuming these parameters could reflect structural changes in the pentavalent antimony molecule, clearly further better controlled experiments are indicated.

  5. Antimony segregation in stressed SiGe heterostructures grown by molecular beam epitaxy

    International Nuclear Information System (INIS)

    The effects of the growth temperature, composition, and elastic strains in separate layers on the segregation of antimony are studied experimentally for stressed SiGe structures grown by molecular beam epitaxy. It is established that the growth conditions and parameters of the structures exert an interrelated influence on the segregation of Sb: the degree of the influence of the composition and elastic stresses in the SiGe layers on Sb segregation depends on the growth temperature. It is shown that usage of a method previously proposed by us for the selective doping of silicon structures with consideration for the obtained dependences of Sb segregation on the growth conditions and parameters of the SiGe layers makes it possible to form SiGe structures selectively doped with antimony

  6. Deciphering lead and cadmium stripping peaks for porous antimony deposited electrodes

    Directory of Open Access Journals (Sweden)

    Taimoor Aqeel Ahmad

    2016-06-01

    Full Text Available Cadmium and lead are generally taken as model heavy metal ions in water to scale the detection limit of various electrode sensors, using electrochemical sensing techniques. These ions interact with the electrochemically deposited antimony electrodes depending on the diffusion limitations. The phenomenon acts differently for the in-situ and ex-situ deposition as well as for porous and non-porous electrodes. A method has been adopted in this study to discourage the stripping and deposition of the working ions (antimony to understand the principle of heavy metal ion detection. X-ray photoelectron spectroscopy (XPS technique was used to establish the interaction between the working and dissolved ions. In addition to the distinct peaks for each analyte, researchers also observed a shoulder peak. A possible reason for the presence of this peak was provided. Different electrochemical tests were performed to ascertain the theory on the basis of the experimental observations.

  7. 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.

  8. Bi-antimony capped Keggin polyoxometalate modified with Cu-ligand fragment

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Jiao [College of Chemistry and Material Science, Hebei Normal University, No. 20 Road East of 2nd Ring South, Yuhua District, Shijiazhuang, Hebei 050024 (China); Han, Zhangang, E-mail: hanzg116@yahoo.com.cn [College of Chemistry and Material Science, Hebei Normal University, No. 20 Road East of 2nd Ring South, Yuhua District, Shijiazhuang, Hebei 050024 (China); Zhang, Heng; Yu, Haitao [College of Chemistry and Material Science, Hebei Normal University, No. 20 Road East of 2nd Ring South, Yuhua District, Shijiazhuang, Hebei 050024 (China); Zhai, Xueliang, E-mail: xlzhai253@mail.hebtu.edu.cn [College of Chemistry and Material Science, Hebei Normal University, No. 20 Road East of 2nd Ring South, Yuhua District, Shijiazhuang, Hebei 050024 (China)

    2012-10-15

    Three polyoxometalates consisting of bi-antimony capped Keggin-type clusters: [Cu(mbpy){sub 2}]{sub 2}[PMo{sub 12}O{sub 40}Sb{sub 2}]{center_dot}4H{sub 2}O (1), [Cu(mbpy){sub 2}][PMo{sub 12}O{sub 40}Sb{sub 2}] (2) and {l_brace}Cu(mbpy)[Cu(mbpy){sub 2}]{sub 2}{r_brace}[VMo{sub 8}V{sub 4}O{sub 40}Sb{sub 2}]{center_dot}2H{sub 2}O (3) (mbpy=4,4 Prime -dimethyl-2,2 Prime - dipyridyl in 1 and 2; 5,5 Prime -dimethyl-2,2 Prime -dipyridyl in 3) have been synthesized and characterized by IR, X-ray powder diffraction, TG analysis and electrochemical property. Single-crystal analysis revealed that all of three compounds are built upon bi-antimony capped Keggin-type polyoxoanions and Cu-mbpy cations. In 1-3, two Sb{sup III} centers located at the two opposite of anionic surface adopt fundamentally tetragonal pyramidal coordination geometry. Both compounds 1 and 2 consist of P-centered Keggin structure, while compound 3 presents a V-centered Keggin anion. The Keggin-type anions present different structural features: isolated cluster in 1 and Cu-ligand-supported cluster in 2 and 3. - Graphical abstract: Three hybrid compounds consisting of bi-antimony capped Keggin-type clusters modified with Cu-ligand cations have been synthesized and characterized. Highlights: Black-Right-Pointing-Pointer Three hybrid compounds consisting of bi-antimony capped Keggin-type clusters have been synthesized. Black-Right-Pointing-Pointer Two Sb{sup III} centers located at the two opposite of anionic surface adopt tetragonal pyramidal coordination geometry. Black-Right-Pointing-Pointer The anions present different structural features: isolated and Cu-ligand-supported cluster.

  9. Metal corrosion studies with the fluorosulphonic acid-antimony pentafluoride superacid system

    International Nuclear Information System (INIS)

    Because of their rapid dissolution of many actinide metals and refractory oxides, superacids such as HSO3F/SbF5 have potential applications in actinide processing. However, material compatibility must first be addressed because of the highly corrosive nature of superacids. This paper describes the qualitative rates of attack of fluorosulphonic acid-antimony pentafluoride superacid on a variety of metal substrates relevant to nuclear processing

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

    OpenAIRE

    Rajmund Michalski; Sebastian Szopa; Magdalena Jabłońska; Aleksandra Łyko

    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 biogeochemi...

  11. Electrodeposition Mechanism of Trivalent Antimony%三价锑的电沉积机理

    Institute of Scientific and Technical Information of China (English)

    林艳; 谢刚; 杨大锦

    2011-01-01

    The reduction mechanism of Sb3+ in H2SO4-NH4F-SbF3 electrolyte system was studied by means of electrochemical methods, including chronopotentiometry and alternating current impedance.Analysis of potential-time transients clearly shows that antimony (Ⅲ) could be reduced to antimony metal via two-steps irreversible electron transfer process in H2SO4-NH4F-SbF3 system.The relationship between iτ1/2 and i calculated by chronopotentiometry indicates that the trivalent antimony complex undergoes chemical transformation reaction before its reduction in the cathode.The impedance results confirm the above conclusion and indicate that the adsorption states which are the middle product of trivalent antimony have different influences on two electron transfer steps.%采用恒电流阶跃法及交流阻抗法等电化学方法,研究了H2SO4-NH4F-SbF3体系中三价锑的阴极还原机理.电势~时间暂态曲线出现二步反应特征,表明Sb"还原分两步进行.由恒电流阶跃曲线中iτ1/2~i关系可知Sb3+阴极还原存在前置化学转化.Sb3+阴极还原的交流阻抗测定结果进一步验证Sb3+还原是存在化学前置转化步骤的二步反应,且电活性中间产物吸附在电极表面,吸附反应对两步电子转移步骤的影响不同.

  12. Studies in atomic-fluorescence spectroscopy-V The fluorescence characteristics and determination of antimony.

    Science.gov (United States)

    Dagnall, R M; Thompson, K C; West, T S

    1967-10-01

    Atomic-fluorescence of antimony may be generated in an air-propane flame by nebulizing aqueous solutions of antimony salts whilst irradiating the flame by means of a microwave-excited electrode-less discharge tube operating at 30 W. The strongest fluorescence is exhibited by the (4)S(11 2 ) --> (4)P(1 3 ) 2311 A resonance line and weaker signals are observed at the 2068 and 2176 A resonance lines and at four intercombination lines, at 2598, 2671, 2770 and 2878 A. A process of thermally assisted direct-line fluorescence is postulated to account for the otherwise inexplicable intensity of the 2598 A line emission. Atomic-fluorescence spectroscopy at 2176 A permits the determination of antimony in the range 0.1-120 ppm with a detection limit of 0.05 ppm. With the same equipment and source, the range of measurement for atomic-absorption was 6-120 ppm and the detection limit was 1 ppm. No interferences were observed from 100-fold molar amounts of Cd, Co, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, NH(4), Pb and Zn or from arsenate, chloride, nitrate, phosphate and sulphate. PMID:18960212

  13. Morphology and antimony segregation of spangles on batch hot-dip galvanized coatings

    International Nuclear Information System (INIS)

    Spangles produced by batch hot-dip galvanizing process have a rougher surface and a greater surface segregation of alloying element compared with those in continuous hot-dip galvanizing line (CGL), owing to the cooling rate of the former is much smaller than that of the later. Therefore, typical spangles on a batch hot-dipped Zn-0.05Al-0.2Sb alloy coating were investigated. The chemical, morphological characterization and identification of the phases on the spangles were examined by scanning electron microscopy (SEM), backscattered electron imaging (BSE), atomic force microscopy (AFM), energy dispersive spectroscopy (EDS) and X-ray diffraction analysis (XRD). The results showed that the coating surface usually exhibited three kinds of spangles: shiny, feathery and dull spangle, of which extensively antimony surface segregation was detected. The nature of precipitate on the coating surface was identified as β-Sb3Zn4, The precipitated β-Sb3Zn4 particles distributed randomly on the shiny spangle surface, both β-Sb3Zn4 particles and dentritic segregation of antimony dispersed in the dendritic secondary arm spacings of the feathery spangle and on the whole dull spangle surface. The dentritic segregation of antimony and precipitation of Sb3Zn4 compound are discussed by a proposed model.

  14. 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

  15. 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.

  16. Phase diagram of (Li(1-x)Fe(x))OHFeSe: a bridge between iron selenide and arsenide superconductors.

    Science.gov (United States)

    Dong, Xiaoli; Zhou, Huaxue; Yang, Huaixin; Yuan, Jie; Jin, Kui; Zhou, Fang; Yuan, Dongna; Wei, Linlin; Li, Jianqi; Wang, Xinqiang; Zhang, Guangming; Zhao, Zhongxian

    2015-01-14

    Previous experimental results have shown important differences between iron selenide and arsenide superconductors which seem to suggest that the high-temperature superconductivity in these two subgroups of iron-based families may arise from different electronic ground states. Here we report the complete phase diagram of a newly synthesized superconducting (SC) system, (Li1-xFex)OHFeSe, with a structure similar to that of FeAs-based superconductors. In the non-SC samples, an antiferromagnetic (AFM) spin-density-wave (SDW) transition occurs at ∼127 K. This is the first example to demonstrate such an SDW phase in an FeSe-based superconductor system. Transmission electron microscopy shows that a well-known √5×√5 iron vacancy ordered state, resulting in an AFM order at ∼500 K in AyFe2-xSe2 (A = metal ions) superconductor systems, is absent in both non-SC and SC samples, but a unique superstructure with a modulation wave vector q = (1)/2(1,1,0), identical to that seen in the SC phase of KyFe2-xSe2, is dominant in the optimal SC sample (with an SC transition temperature Tc = 40 K). Hence, we conclude that the high-Tc superconductivity in (Li1-xFex)OHFeSe stems from the similarly weak AFM fluctuations as FeAs-based superconductors, suggesting a universal physical picture for both iron selenide and arsenide superconductors.

  17. Phase diagram of (Li(1-x)Fe(x))OHFeSe: a bridge between iron selenide and arsenide superconductors.

    Science.gov (United States)

    Dong, Xiaoli; Zhou, Huaxue; Yang, Huaixin; Yuan, Jie; Jin, Kui; Zhou, Fang; Yuan, Dongna; Wei, Linlin; Li, Jianqi; Wang, Xinqiang; Zhang, Guangming; Zhao, Zhongxian

    2015-01-14

    Previous experimental results have shown important differences between iron selenide and arsenide superconductors which seem to suggest that the high-temperature superconductivity in these two subgroups of iron-based families may arise from different electronic ground states. Here we report the complete phase diagram of a newly synthesized superconducting (SC) system, (Li1-xFex)OHFeSe, with a structure similar to that of FeAs-based superconductors. In the non-SC samples, an antiferromagnetic (AFM) spin-density-wave (SDW) transition occurs at ∼127 K. This is the first example to demonstrate such an SDW phase in an FeSe-based superconductor system. Transmission electron microscopy shows that a well-known √5×√5 iron vacancy ordered state, resulting in an AFM order at ∼500 K in AyFe2-xSe2 (A = metal ions) superconductor systems, is absent in both non-SC and SC samples, but a unique superstructure with a modulation wave vector q = (1)/2(1,1,0), identical to that seen in the SC phase of KyFe2-xSe2, is dominant in the optimal SC sample (with an SC transition temperature Tc = 40 K). Hence, we conclude that the high-Tc superconductivity in (Li1-xFex)OHFeSe stems from the similarly weak AFM fluctuations as FeAs-based superconductors, suggesting a universal physical picture for both iron selenide and arsenide superconductors. PMID:25532066

  18. Comparison of oral itraconazole and intramuscular meglumine antimoniate in the treatment of cutaneous leishmaniasis

    International Nuclear Information System (INIS)

    To compare the efficacy and tolerability of oral itraconazole against intramuscular meglumine antimoniate in the treatment of Cutaneous Leishmaniasis (CL). Two hundred eligible and consenting patients of Cutaneous Leishmaniasis (CL) were divided in two groups with 100 patients in each. The number and location of the lesions were documented and clinical types of cutaneous leishmaniasis were noted. The diagnosis was confirmed by skin slit smear and histopathology of the lesional skin. Culture on Nicolle Novy MacNeal (NNN) medium and Leishmanin test was done in all patients. All the patients in both groups were subjected to complete blood picture, urine examination, serum urea and creatinine levels and ECG examination. One group was given itraconazole 100 mg twice daily orally for a duration of 6-8 weeks. The other group was given meglumine antimoniate 10 cc in the form of deep intramuscular injections for 15-30 days. The efficacy of the treatment was judged by clinical and parasitological response. Side effects of the agents were also noted during treatment. Out of 200 patients studied, 185 were males and 15 were females. The mean age of presentation was 30 + 6.6 years. Single lesion was seen in 132 (66%) subjects whereas 68 (34%) subjects had multiple lesions. Slit skin smears were positive in 50 (25%) of the patients. Skin biopsy yielded the presence of LT bodies in 150 (75%) subjects. The culture was positive in 102 (51%) cases. Leishmanin test was positive in 94% subjects. Seventy-five (75%) patients on itraconazole therapy showed complete clinical and parasitological cure in 4-8 weeks duration. A rise in ALT was seen in 12% subjects. Five (5%) subjects did not show any improvement till the end of therapy. Sixty-five (65%) subjects on meglumine antimoniate showed complete healing in 15-30 days. In 35 (35%) of the patients, the treatment had to be stopped due to intolerable side-effects. Four cases of lupoid leishmaniasis and 4 cases of sporotrichoid leishmaniasis

  19. A study on the optics of copper indium gallium (di)selenide (CIGS) solar cells with ultra-thin absorber layers

    NARCIS (Netherlands)

    Xu, M.; Wachters, A.J.H.; Deelen, J. van; Mourad, M.C.D.; Buskens, P.J.P.

    2014-01-01

    We present a systematic study of the effect of variation of the zinc oxide (ZnO) and copper indium gallium (di)selenide (CIGS) layer thickness on the absorption characteristics of CIGS solar cells using a simulation program based on finite element method (FEM). We show that the absorption in the CIG

  20. Soft chemical control of superconductivity in lithium iron selenide hydroxides Li(1-x)Fe(x)(OH)Fe(1-y)Se.

    Science.gov (United States)

    Sun, Hualei; Woodruff, Daniel N; Cassidy, Simon J; Allcroft, Genevieve M; Sedlmaier, Stefan J; Thompson, Amber L; Bingham, Paul A; Forder, Susan D; Cartenet, Simon; Mary, Nicolas; Ramos, Silvia; Foronda, Francesca R; Williams, Benjamin H; Li, Xiaodong; Blundell, Stephen J; Clarke, Simon J

    2015-02-16

    Hydrothermal synthesis is described of layered lithium iron selenide hydroxides Li(1-x)Fe(x)(OH)Fe(1-y)Se (x ∼ 0.2; 0.02 iron site vacancy concentrations in the iron selenide layers. This iron vacancy concentration is revealed as the only significant compositional variable and as the key parameter controlling the crystal structure and the electronic properties. Single crystal X-ray diffraction, neutron powder diffraction, and X-ray absorption spectroscopy measurements are used to demonstrate that superconductivity at temperatures as high as 40 K is observed in the hydrothermally synthesized samples when the iron vacancy concentration is low (y iron oxidation state is reduced slightly below +2, while samples with a higher vacancy concentration and a correspondingly higher iron oxidation state are not superconducting. The importance of combining a low iron oxidation state with a low vacancy concentration in the iron selenide layers is emphasized by the demonstration that reductive postsynthetic lithiation of the samples turns on superconductivity with critical temperatures exceeding 40 K by displacing iron atoms from the Li(1-x)Fe(x)(OH) reservoir layer to fill vacancies in the selenide layer.

  1. Methods of making copper selenium precursor compositions with a targeted copper selenide content and precursor compositions and thin films resulting therefrom

    Science.gov (United States)

    Curtis, Calvin J.; Miedaner, Alexander; van Hest, Marinus Franciscus Antonius Maria; Ginley, David S.; Leisch, Jennifer; Taylor, Matthew; Stanbery, Billy J.

    2011-09-20

    Precursor compositions containing copper and selenium suitable for deposition on a substrate to form thin films suitable for semi-conductor applications. Methods of forming the precursor compositions using primary amine solvents and methods of forming the thin films wherein the selection of temperature and duration of heating controls the formation of a targeted species of copper selenide.

  2. Cytocompatibility of direct water synthesized cadmium selenide quantum dots in colo-205 cells

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Torres, Marcos R. [Universidad Metropolitana, Nanomaterials Science Laboratory, School of Science and Technology (United States); Velez, Christian; Zayas, Beatriz [Universidad Metropolitana, ChemTox Laboratory, School of Environmental Affairs (United States); Rivera, Osvaldo [Universidad Metropolitana, Nanomaterials Science Laboratory, School of Science and Technology (United States); Arslan, Zikri [Jackson State University, Department of Chemistry (United States); Gonzalez-Vega, Maxine N. [Universidad Metropolitana, Nanomaterials Science Laboratory, School of Science and Technology (United States); Diaz-Diestra, Daysi; Beltran-Huarac, Juan; Morell, Gerardo [University of Puerto Rico, Molecular Science Research Center (United States); Primera-Pedrozo, Oliva M., E-mail: oprimera1@suagm.edu [Universidad Metropolitana, Nanomaterials Science Laboratory, School of Science and Technology (United States)

    2015-06-15

    Cadmium selenide quantum dots (CdSe QDs), inorganic semiconducting nanocrystals, are alluring increased attraction due to their highly refined chemistry, availability, and super tunable optical properties suitable for many applications in different research areas, such as photovoltaics, light-emitting devices, environmental sciences, and nanomedicine. Specifically, they are being widely used in bio-imaging in contrast to organic dyes due to their high brightness and improved photo-stability, and their ability to tune their absorption and emission spectra upon changing the crystal size. The production of CdSe QDs is mostly assisted by trioctylphosphine oxide compound, which acts as solvent or solubilizing agent and renders the QDs soluble in organic compounds (such as toluene, chloroform, and hexane) that are highly toxic. To circumvent the toxicity-related factor in CdSe QDs, we report the synthesis of CdSe QDs capped with thioglycolic acid (TGA) in an aqueous medium, and their biocompatibility in colo-205 cancer cells. In this study, the [Cd{sup 2+}]/[TGA] ratio was adjusted to 11:1 and the Se concentration (10 and 15 mM) was monitored in order to evaluate its influence on the optical properties and cytocompatibility. QDs resulted to be quite stable in water (after purification) and RPMI cell medium and no precipitation was observed for long contact times, making them appealing for in vitro experiments. The spectroscopy analysis, advanced electron microscopy, and X-ray diffractometry studies indicate that the final products were successfully formed exhibiting an improved optical response. Colo-205 cells being exposed to different concentrations of TGA-capped CdSe QDs for 12, 24, and 48 h with doses ranging from 0.5 to 2.0 mM show high tolerance reaching cell viabilities as high as 93 %. No evidence of cellular apoptotic pathways was observed as pointed out by our Annexin V assays at higher concentrations. Moreover, confocal microscopy analysis conducted to

  3. Cytocompatibility of direct water synthesized cadmium selenide quantum dots in colo-205 cells

    International Nuclear Information System (INIS)

    Cadmium selenide quantum dots (CdSe QDs), inorganic semiconducting nanocrystals, are alluring increased attraction due to their highly refined chemistry, availability, and super tunable optical properties suitable for many applications in different research areas, such as photovoltaics, light-emitting devices, environmental sciences, and nanomedicine. Specifically, they are being widely used in bio-imaging in contrast to organic dyes due to their high brightness and improved photo-stability, and their ability to tune their absorption and emission spectra upon changing the crystal size. The production of CdSe QDs is mostly assisted by trioctylphosphine oxide compound, which acts as solvent or solubilizing agent and renders the QDs soluble in organic compounds (such as toluene, chloroform, and hexane) that are highly toxic. To circumvent the toxicity-related factor in CdSe QDs, we report the synthesis of CdSe QDs capped with thioglycolic acid (TGA) in an aqueous medium, and their biocompatibility in colo-205 cancer cells. In this study, the [Cd2+]/[TGA] ratio was adjusted to 11:1 and the Se concentration (10 and 15 mM) was monitored in order to evaluate its influence on the optical properties and cytocompatibility. QDs resulted to be quite stable in water (after purification) and RPMI cell medium and no precipitation was observed for long contact times, making them appealing for in vitro experiments. The spectroscopy analysis, advanced electron microscopy, and X-ray diffractometry studies indicate that the final products were successfully formed exhibiting an improved optical response. Colo-205 cells being exposed to different concentrations of TGA-capped CdSe QDs for 12, 24, and 48 h with doses ranging from 0.5 to 2.0 mM show high tolerance reaching cell viabilities as high as 93 %. No evidence of cellular apoptotic pathways was observed as pointed out by our Annexin V assays at higher concentrations. Moreover, confocal microscopy analysis conducted to evaluate

  4. 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. PMID:22970588

  5. 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.

  6. 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

  7. Evolution of the chemical bonding nature and electrode activity of indium selenide upon the composite formation with graphene nanosheets

    International Nuclear Information System (INIS)

    Graphical abstract: Display Omitted -- Highlights: • In4Se2.85@graphene nanocomposite is easily prepared by high energy mechanical milling process. • The bond covalency of In4Se2.85 is notably changed upon the composite formation with graphene. • In4Se2.85@graphene nanocomposite shows promising anode performance for lithium ion battery. -- Abstract: Evolution of the chemical bonding nature and electrochemical activity of indium selenide upon the composite formation with carbon species is systematically investigated. Nanocomposites of In4Se2.85@graphene and In4Se2.85@carbon-black are synthesized via a solid state reaction between In and Se elements, and the following high energy mechanical milling of In4Se2.85 with graphene and carbon-black, respectively. The high energy mechanical milling (HEMM) of In4Se2.85 with carbon species gives rise to a decrease of particle size with a significant depression of the crystallinity of In4Se2.85 phase. In contrast to the composite formation with carbon-black, that with graphene induces a notable decrease of (In−Se) bond covalency, underscoring significant chemical interaction between graphene and In4Se2.85. Both the nanocomposites of In4Se2.85@graphene and In4Se2.85@carbon-black show much better anode performance for lithium ion batteries with larger discharge capacity and better cyclability than does the pristine In4Se2.85 material, indicating the beneficial effect of composite formation on the electrochemical activity of indium selenide. Between the present nanocomposites, the electrode performance of the In4Se2.85@graphene nanocomposite is superior to that of the In4Se2.85@carbon-black nanocomposite, which is attributable to the weakening of (In−Se) bonds upon the composite formation with graphene as well as to the better mixing between In4Se2.85 and graphene. The present study clearly demonstrates that the composite formation with graphene has strong influence on the chemical bonds and electrode activity of indium

  8. 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.

  9. 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.

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

    International Nuclear Information System (INIS)

    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 IC50 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)

  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.

    2014-10-01

    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 finding

  12. The LABCG2 Transporter from the Protozoan Parasite Leishmania Is Involved in Antimony Resistance.

    Science.gov (United States)

    Perea, Ana; Manzano, José Ignacio; Castanys, Santiago; Gamarro, Francisco

    2016-06-01

    Treatment for leishmaniasis, which is caused by Leishmania protozoan parasites, currently relies on a reduced arsenal of drugs. However, the significant increase in the incidence of drug therapeutic failure and the growing resistance to first-line drugs like antimonials in some areas of Northern India and Nepal limit the control of this parasitic disease. Understanding the molecular mechanisms of resistance in Leishmania is now a matter of urgency to optimize drugs used and to identify novel drug targets to block or reverse resistant mechanisms. Some members of the family of ATP-binding cassette (ABC) transporters in Leishmania have been associated with drug resistance. In this study, we have focused our interest to characterize LABCG2's involvement in drug resistance in Leishmania. Leishmania major parasites overexpressing the ABC protein transporter LABCG2 were generated in order to assess how LABCG2 is involved in drug resistance. Assays of susceptibility to different leishmanicidal agents were carried out. Analysis of the drug resistance profile revealed that Leishmania parasites overexpressing LABCG2 were resistant to antimony, as they demonstrated a reduced accumulation of Sb(III) due to an increase in drug efflux. Additionally, LABCG2 was able to transport thiols in the presence of Sb(III) Biotinylation assays using parasites expressing LABCG2 fused with an N-terminal green fluorescent protein tag revealed that LABCG2 is partially localized in the plasma membrane; this supports data from previous studies which suggested that LABCG2 is localized in intracellular vesicles that fuse with the plasma membrane during exocytosis. In conclusion, Leishmania LABCG2 probably confers antimony resistance by sequestering metal-thiol conjugates within vesicles and through further exocytosis by means of the parasite's flagellar pocket. PMID:27021316

  13. 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...... supports composed of oxides and carbon and supported platinum catalysts were prepared. Using the pure oxide support, the Pt/ATO catalyst displayed superior specific activity and stability for the oxygen reduction reactions (ORRs). Low surface area of ATO caused poor dispersion of Pt particles compared...

  14. Formation of Metal Selenide and Metal-Selenium Nanoparticles using Distinct Reactivity between Selenium and Noble Metals.

    Science.gov (United States)

    Park, Se Ho; Choi, Ji Yong; Lee, Young Hwan; Park, Joon T; Song, Hyunjoon

    2015-07-01

    Small Se nanoparticles with a diameter of ≈20 nm were generated by the reduction of selenium chloride with NaBH4 at -10 °C. The reaction with Ag at 60 °C yielded stable Ag2 Se nanoparticles, which subsequently were transformed into M-Se nanoparticles (M=Cd, Zn, Pb) through cation exchange reactions with corresponding ions. The reaction with Pt formed Pt layers that were evenly coated on the surface of the Se nanoparticles, and the dissolution of the Se cores with hydrazine generated uniform Pt hollow nanoparticles. The reaction with Au generated tiny Au clusters on the Se surface, and eventually formed acorn-shaped Au-Se nanoparticles through heat treatment. These results indicate that small Se nanoparticles with diameters of ≈20 nm can be used as a versatile platform for the synthesis of metal selenide and metal-selenium hybrid nanoparticles with complex structures.

  15. catena-Poly[[[aquacopper(II]bis[μ-bis(3,5-dimethyl-1H-pyrazol-4-yl selenide

    Directory of Open Access Journals (Sweden)

    Maksym Seredyuk

    2010-05-01

    Full Text Available The title compound, {[Cu(C10H14N4Se2(H2O](BF42·2C18H15PO·H2O}n, has a polymeric structure where each CuII ion adopts a square-pyramidal coordination constituted by four N atoms of pyrazole moieties in the equatorial plane and an axial O atom of a water molecule. A pair of bis(3,5-dimethyl-1H-pyrazol-4-yl selenide ligands bridges the CuII centres into a chain extending along the c axis. The water molecules, anions and triphenylphosphine oxide molecules are involved in intermolecular hydrogen bonding, which links the chains into a three-dimensional network.

  16. Post-test analysis of components from selenide isotope generator modules M-7, M-15, and M-18

    International Nuclear Information System (INIS)

    Several critical components removed from SIG (Selenide Isotope Generator) thermoelectric modules M-7, M-15C, M-15D, and M-18 were examined. These modules failed to show the predicted stability and conversion efficiency. Understanding the degradation and identifying means for preventing it necessitated detailed post-test examinations of key parts in the modules. Steel springs, which provided pressure for contacts at the hot and cold ends of P- or N-legs, relaxed more than expected. Beryllium oxide insulators had dark deposits that caused electrical shorts. The GdSe149 N-leg exhibited cracking. The (Cu,Ag)2Se P-leg lost weight or sublimed excessively in module M-7 and more than expected in the other modules

  17. Cuprous Iodide Catalyzed Synthesis of Diaryl Selenide and Telluride from Organoboronic Acids with Diphenyl Diselenide and Ditelluride

    Institute of Scientific and Technical Information of China (English)

    WANG,Lei; WANG,Min; YAN,Jin-Can; LI,Pin-Hua

    2004-01-01

    @@ Organoselenium and tellurium compounds have received much attention not only as synthetic reagents or intermediates in organic synthesis but also as promising donor molecules for conductive materials.[1] A number of synthetic methods have been reported to prepare organoselenium and tellurium derivatives. A convenient and general method to introduce a selenium or tellurium moiety into organic molecules is the reaction of a metal selenolate or tellurolate with appropriate electrophiles such as organic halides, acyl chlorides, epoxides, and α, β-enones.[2] However, it is difficult to synthesize the unsymmetrical diarylselenides and tellurides through the reaction of selenide anion with organic halides because of the less reactivity of aryl halides. To accomplish this purpose, the reaction (iodobenzene with phenylselenol)was generally carried out in the presence of catalysts, ligands and strong bases. But, the reaction needs longer time to accomplish and form the products in moderate yields.

  18. A novel polysaccharide isolated from mulberry fruits (Murus alba L.) and its selenide derivative: structural characterization and biological activities.

    Science.gov (United States)

    Chen, Chun; Zhang, Bin; Fu, Xiong; Liu, Rui Hai

    2016-06-15

    A novel polysaccharide (MFP3P) was isolated from Murus alba L. through the hot water extraction method followed by chromatographic purification. The chemical structure of MFP3P was elucidated by acid hydrolysis, Smith degradation and methylation analysis, along with FT-IR, GC-MS, (1)H and (13)C NMR spectroscopy. Its morphological properties were further characterized by SEM and AFM. The selenide of the polysaccharide (MFP3P-Se) was obtained by the Na2SeO3/BaCl2 method. The antioxidant properties showed that MFP3P-Se exhibited higher peroxy radical-scavenging capacity than MFP3P in vitro. Moreover, MFP3P-Se had more significant hypoglycemic effects than MFP3P through promoting pancreatic cell proliferation and increasing glucose metabolism and insulin secretion. PMID:27241036

  19. Post-test analysis of components from selenide isotope generator modules M-7, M-15, and M-18

    Energy Technology Data Exchange (ETDEWEB)

    Wei, G.C.; Keiser, J.R.; Crouse, R.S.; Allen, M.D.; Schaffhauser, A.C.

    1979-05-01

    Several critical components removed from SIG (Selenide Isotope Generator) thermoelectric modules M-7, M-15C, M-15D, and M-18 were examined. These modules failed to show the predicted stability and conversion efficiency. Understanding the degradation and identifying means for preventing it necessitated detailed post-test examinations of key parts in the modules. Steel springs, which provided pressure for contacts at the hot and cold ends of P- or N-legs, relaxed more than expected. Beryllium oxide insulators had dark deposits that caused electrical shorts. The GdSe/sub 1/ /sub 49/ N-leg exhibited cracking. The (Cu,Ag)/sub 2/Se P-leg lost weight or sublimed excessively in module M-7 and more than expected in the other modules.

  20. Separation of antimony from synthetic cloth. Application in forensic science using neutron activation analysis

    International Nuclear Information System (INIS)

    A simple ion-exchange separation procedure was developed for selective removal of antimony from synthetic cloth to facilitate determination of several trace elements frequently used to identify gunshot residues by neutron activation analysis. Radiotracers of Sb, Ba, Cu, Co, As, Zn, Hg and Ag were employed to optimize the developed procedure. The method involves the quantitative retention of the above elements, except of Sb, from 0.2M ammonium carbonate solution using Chelex 100 resin and subsequent quantitative elution of the elements of interest with 2M nitric acid for gamma-ray spectrometry. The procedure was tested by simulated gunshot residues. (author)

  1. Influence of arsenic,antimony and cobalt impurities on the cathodic process in zinc electrowinning

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    By means of an electrochemical study,the influence of arsenic,antimony and cobalt on cathodic polarization in the zinc electrowinning process,the associated kinetic equations and parameters,and the polarization mechanism have been studied.The results show that the experimental values of the kinetic parameters are in accord with the theoretical values in the ZnSO4/H2SO4 solution with a single impurity is added.In contrast,the charge transfer coefficient α is smaller than the theoretical value in the ZnSO4/H2SO4 solution when the three impurities are added together.

  2. Polymorphism and properties of Bi{sub 2}WO{sub 6} doped with pentavalent antimony

    Energy Technology Data Exchange (ETDEWEB)

    Kharitonova, E.P.; Belov, D.A. [M.V. Lomonosov Moscow State University, Leninskie Gory, 119991 Moscow (Russian Federation); Gagor, A.B.; Pietraszko, A.P. [W. Trzebiatowski Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Okólna 2, 50-950 Wrocław (Poland); Alekseeva, O.A. [Shubnikov Institute of Crystallography, Russian Academy of Sciences, Leninsky pr. 59, 119333 Moscow (Russian Federation); Voronkova, V.I., E-mail: voronk@polly.phys.msu.ru [M.V. Lomonosov Moscow State University, Leninskie Gory, 119991 Moscow (Russian Federation)

    2014-04-05

    Highlights: • The limit of Bi{sub 2}W{sub 1−x}Sb{sub x}O{sub 6−y} solid solutions is at x = 0.05. • Bi{sub 2}W{sub 1−x}Sb{sub x}O{sub 6−y} does not fully transform into high-temperature monoclinic phase. • Sb{sup 5+} has a weak effect on the temperatures of the ferroelectric transitions. • γ→γ{sup ‴} transition near 650 °C was observed as strong permittivity peak at 0.01–8 Hz. • The conductivity of Bi{sub 2}W{sub 0.96}Sb{sub 0.04}O{sub 6−y} at 800 °C reaches 0.02 S/cm. -- Abstract: Antimony-containing solid solutions isostructural with bismuth tungstate, Bi{sub 2}WO{sub 6}, have been prepared in air as polycrystalline samples by solid-state reactions and as single crystals by unseeded flux growth. The antimony in the solid solutions is in a pentavalent state and substitutes for tungsten in the structure of Bi{sub 2}WO{sub 6}. The Bi{sub 2}W{sub 1−x}Sb{sub x}O{sub 6−y} solid solutions have been shown to exist in the composition range 0 ⩽ x ⩽ 0.05. We have examined the effect of Sb{sup 5+} doping on the polymorphism and properties of Bi{sub 2}WO{sub 6}. In contrast to undoped Bi{sub 2}WO{sub 6}, antimony-substituted bismuth tungstate does not completely transform into its high-temperature, monoclinic phase at 960 °C and remains two-phase up to temperatures approaching its melting point. Antimony substitution for tungsten has a weak effect on the temperatures of the ferroelectric phase transitions. Heterovalent substitution of Sb{sup 5+} for W{sup 6+} is accompanied by the formation of extra oxygen vacancies and an increase in the electrical conductivity of the solid solutions by one to two orders of magnitude relative to undoped Bi{sub 2}WO{sub 6}.

  3. Electromagnetic absorption and shielding behavior of polyaniline-antimony oxide composites

    Science.gov (United States)

    Faisal, Muhammad; Khasim, Syed

    2013-02-01

    This work highlights the microwave absorption and electromagnetic interference (EMI) shielding properties of synthesized polyaniline (PAni)-antimony oxide (Sb2O3) composites in the 8-12 GHz (X-band) range. These composites showed absorption dominated EMI shielding effectiveness (EMI SEA) of -34 to -40 dB (> 99 % attenuation), indicating their shielding potential throughout the X-band. Our analyses reveal that the Sb2O3 particles in PAni matrix have key impact in determining the microwave absorption properties of the composites.

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

    International Nuclear Information System (INIS)

    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

  5. Nanoscale arrays of antimony telluride single crystals by selective chemical vapor deposition

    Science.gov (United States)

    Huang, Ruomeng; Benjamin, Sophie L.; Gurnani, Chitra; Wang, Yudong; Hector, Andrew L.; Levason, William; Reid, Gillian; De Groot, C. H. (Kees)

    2016-01-01

    Arrays of individual single nanocrystals of Sb2Te3 have been formed using selective chemical vapor deposition (CVD) from a single source precursor. Crystals are self-assembled reproducibly in confined spaces of 100 nm diameter with pitch down to 500 nm. The distribution of crystallite sizes across the arrays is very narrow (standard deviation of 15%) and is affected by both the hole diameter and the array pitch. The preferred growth of the crystals in the orientation along the diagonal of the square holes strongly indicates that the diffusion of adatoms results in a near thermodynamic equilibrium growth mechanism of the nuclei. A clear relationship between electrical resistivity and selectivity is established across a range of metal selenides and tellurides, showing that conductive materials result in more selective growth and suggesting that electron donation is of critical importance for selective deposition. PMID:27283116

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

    International Nuclear Information System (INIS)

    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.

  7. Canine visceral leishmaniasis: comparison of in vitro leishmanicidal activity of marbofloxacin, meglumine antimoniate and sodium stibogluconate.

    Science.gov (United States)

    Vouldoukis, Ioannis; Rougier, Sandrine; Dugas, Bernard; Pino, Paco; Mazier, Dominique; Woehrlé, Frédérique

    2006-01-30

    The control of canine leishmaniasis largely depends on the success of treatment. Drugs currently available to treat this disease are toxic and partially effective. The curative effect of marbofloxacin, a third-generation fluoroquinolone developed for veterinarian individual treatment, was evaluated in vitro in the presence of Leishmania infantum promastigotes and dog-monocyte-derived macrophages; meglumine antimoniate and sodium stibogluconate were used as comparative treatments. We observed that the killing of Leishmania promastigotes and intracellular amastigotes by marbofloxacin was dose-dependent. We demonstrated that successful treatment of canine infected macrophages for 48 h was possible with 500 microg/ml of marbofloxacin. Leishmanicidal activity acted through a TNF-alpha and nitric oxide pathway and correlated with the generation of nitric oxide (NO(2)) production by monocytes derived macrophages from infected (23+/-5 microM) or healthy (21+/-6 microM) dogs, in comparison with NO(2) concentration in infected/non-treated macrophages (Marbofloxacin was shown to be non-toxic at 500 microg/ml in vitro and no cell apoptosis was observed. The molecule was able to induce a parasitic process after significant elimination of amastigotes in leishmania-infected dog macrophages. We propose that marbofloxacin, compared to standard chemotherapeutic agents (meglumine antimoniate and sodium stibogluconate), could be an effective and pragmatic oral route alternative to treat canine leishmaniasis.

  8. 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.

  9. Antimony retention and release from drained and waterlogged shooting range soil under field conditions.

    Science.gov (United States)

    Hockmann, Kerstin; Tandy, Susan; Lenz, Markus; Reiser, René; Conesa, Héctor M; Keller, Martin; Studer, Björn; Schulin, Rainer

    2015-09-01

    Many soils polluted by antimony (Sb) are subject to fluctuating waterlogging conditions; yet, little is known about how these affect the mobility of this toxic element under field conditions. Here, we compared Sb leaching from a calcareous shooting range soil under drained and waterlogged conditions using four large outdoor lysimeters. After monitoring the leachate samples taken at bi-weekly intervals for >1.5 years under drained conditions, two of the lysimeters were subjected to waterlogging with a water table fluctuating according to natural rainfall water infiltration. Antimony leachate concentrations under drained conditions showed a strong seasonal fluctuation between 110 μg L(-1) in summer and soil solution indicated that this decrease in Sb(V) concentrations was attributable to the reduction of Sb(V) to Sb(III) and the stronger sorption affinity of the latter to iron (Fe) (hydr)oxide phases. Our results demonstrate the importance of considering seasonal and waterlogging effects in the assessment of the risks from Sb-contaminated sites. PMID:25592464

  10. A Black Phosphate Conversion Coating on Steel Surface Using Antimony(III)-Tartrate as an Additive

    Science.gov (United States)

    Li, Feng; Wang, Guiping

    2016-05-01

    A novel black phosphate conversion coating was formed on steel surface through a Zn-Mn phosphating bath containing mainly ZnO, H3PO4, Mn(H2PO4)2, and Ca(NO3)2, where antimony(III)-tartrate was used as the blackening agent of phosphatization. The surface morphology and composition of the coating were characterized by scanning electron microscopy, energy dispersion spectroscopy, and x-ray photoelectron spectroscopy. Corrosion resistance of the coating was studied by potentiodynamic polarization curves and electrochemical impedance spectroscopy. The pH value of the solution had significant influence on the formation and corrosion resistance of the coating. The experimental results indicated that the Sb plays a vital role in the blackening of phosphate conversion coating. The optimal concentration of antimony(III)-tartrate in the phosphating bath used in this experiment was 1.0 g L-1, as higher values reduced the corrosion resistance of the coating. In addition, by saponification and oil seals, the corrosion duration of the black phosphate coating in a copper sulfate spot test can be as long as 20 min.

  11. 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.

  12. 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.

  13. Organically complexed iron enhances bioavailability of antimony to maize (Zea mays) seedlings in organic soils.

    Science.gov (United States)

    Ptak, Corey; McBride, Murray

    2015-12-01

    Antimony (Sb) is a metalloid belonging to group 15 of the periodic table. Chemical similarities between arsenic (As) and Sb produce concerns about potential health effects of Sb and enrichment in the environment. Antimony is found in oxic environments predominately as an oxyanionic species, antimonite (Sb[OH](6-)). As a result of its net negative charge, Sb[OH](6-) was not initially predicted to have strong interactions with natural organic matter. Oxyanionic species could bind the negatively charged organic matter via a ternary complexation mechanism, in which cationic metals mediate the strong association between organic matter functional groups and oxyanions. However, these interactions are poorly understood in how they influence the bioavailability of oxyanionic contaminants to plants. Iron (Fe) additions to organic soils have been found to increase the number of organically complexed Fe sites suitable for Sb exchange, resulting in a reduced bioavailable fraction of Sb. The bioavailability of Sb to maize seedlings as a function of organically complexed Fe was examined using a greenhouse study. A significant increase in plant tissue Sb was observed as organically complexed Fe increased, which was not predicted by methods commonly used to assess bioavailable Sb. Extraction of soils with organic acids common to the maize rhizosphere suggested that organic acid exudation can readily mobilize Sb bound by organic Fe complexes. PMID:26076768

  14. Morphology-controlled growth of crystalline antimony sulfide via a refluxing polyol process

    Science.gov (United States)

    Zhang, Rui; Chen, Xiangying; Mo, Maosong; Wang, Zhenghua; Zhang, Meng; Liu, Xinyuan; Qian, Yitai

    2004-02-01

    By refluxing antimony trichloride (SbCl 3) and thiourea in various solvents at suitable reaction conditions, antimony sulfide (Sb 2S 3) crystallites with a diversity of well-defined morphologies were synthesized. Sb 2S 3 rods with the average diameter of 800 nm and the length of 7 μm, as well as microtubes with the average outer diameter of 1.2 μm, the average inner diameter of 800 nm and the length of 8 μm, were obtained in 1,2-propanediol at 180°C for 10 min. In contrast, a series of experiments under different conditions were carried out to investigate the influencing factors on the reaction. The as-synthesized products were characterized by powder X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscope and X-ray photoelectron spectra. The results indicate Sb 2S 3 crystals with different morphologies, including rod-like, tube-like, bowknot-like, flower-like, straw-bundled-like, taken under different experimental conditions. It is found that the reaction temperature, time, solvent and poly(vinyl pyrrolidone) (as a polymer capping reagent) play important roles in the formation of the final Sb 2S 3 crystallites with different morphologies. Also, the possible growth mechanism is discussed.

  15. Organically complexed iron enhances bioavailability of antimony to maize (Zea mays) seedlings in organic soils.

    Science.gov (United States)

    Ptak, Corey; McBride, Murray

    2015-12-01

    Antimony (Sb) is a metalloid belonging to group 15 of the periodic table. Chemical similarities between arsenic (As) and Sb produce concerns about potential health effects of Sb and enrichment in the environment. Antimony is found in oxic environments predominately as an oxyanionic species, antimonite (Sb[OH](6-)). As a result of its net negative charge, Sb[OH](6-) was not initially predicted to have strong interactions with natural organic matter. Oxyanionic species could bind the negatively charged organic matter via a ternary complexation mechanism, in which cationic metals mediate the strong association between organic matter functional groups and oxyanions. However, these interactions are poorly understood in how they influence the bioavailability of oxyanionic contaminants to plants. Iron (Fe) additions to organic soils have been found to increase the number of organically complexed Fe sites suitable for Sb exchange, resulting in a reduced bioavailable fraction of Sb. The bioavailability of Sb to maize seedlings as a function of organically complexed Fe was examined using a greenhouse study. A significant increase in plant tissue Sb was observed as organically complexed Fe increased, which was not predicted by methods commonly used to assess bioavailable Sb. Extraction of soils with organic acids common to the maize rhizosphere suggested that organic acid exudation can readily mobilize Sb bound by organic Fe complexes.

  16. Effect of antimony incorporation on structural properties of CuInS{sub 2} crystals

    Energy Technology Data Exchange (ETDEWEB)

    Ben Rabeh, M., E-mail: mohamedbenrabeh@yahoo.f [Laboratoire de Photovoltaique et Materiaux Semi-Conducteurs - ENIT BP 37, Le belvedere, 1002 Tunis (Tunisia); Chaglabou, N., E-mail: nadia_chaglabou@yahoo.f [Laboratoire de Photovoltaique et Materiaux Semi-Conducteurs - ENIT BP 37, Le belvedere, 1002 Tunis (Tunisia); Kanzari, M., E-mail: Mounir.Kanzari@ipeit.rnu.t [Laboratoire de Photovoltaique et Materiaux Semi-Conducteurs - ENIT BP 37, Le belvedere, 1002 Tunis (Tunisia)

    2010-02-15

    CuInS{sub 2} (CIS) single crystals doped with 1, 2, 3 and 4 atomic percent (at.%) of antimony (Sb) were grown by the horizontal Bridgman method. The effect of Sb doping on the structural properties of CIS crystal was studied by means of X-ray diffraction (XRD), energy dispersive X-ray analysis (EDAX), scanning electron microscopy (SEM) and PL measurements. X-ray diffraction data suggests that the doping of Sb in the CIS single crystals does not affect the tetragonal (chalcopyrite) crystal structure and exhibited a (1 1 2) preferred orientation. In addition, with increasing Sb concentration, the X-ray diffraction analysis show that Sb doped CIS crystals are more crystallized and the diffraction peaks of the CuInS{sub 2} phase were more pronounced in particular the (1 1 2) plane. EDAX study revealed that Sb atoms can occupy the indium site and/or occupying the sulfur site to make an acceptor. PL spectra of undoped and Sb doped CIS crystals show two emission peaks at 1.52 and 1.62 eV, respectively which decreased with increasing atomic percent antimony. Sb doped CIS crystals show p-type conductivity.

  17. Food crop accumulation and bioavailability assessment for antimony (Sb) compared with arsenic (As) in contaminated soils.

    Science.gov (United States)

    Wilson, Susan C; Tighe, Matthew; Paterson, Ewan; Ashley, Paul M

    2014-10-01

    Field samples and a 9-week glasshouse growth trial were used to investigate the accumulation of mining derived arsenic (As) and antimony (Sb) in vegetable crops growing on the Macleay River Floodplain in Northern New South Wales, Australia. The soils were also extracted using EDTA to assess the potential for this extractant to be used as a predictor of As and Sb uptake in vegetables, and a simplified bioaccessibility extraction test (SBET) to understand potential for uptake in the human gut with soil ingestion. Metalloids were not detected in any field vegetables sampled. Antimony was not detected in the growth trial vegetable crops over the 9-week greenhouse trial. Arsenic accumulation in edible vegetable parts was risk of exposure through short-term vegetable crops is low. The data also demonstrate that uptake pathways for Sb and As in the vegetables were different with uptake strongly impacted by soil properties. A fraction of soil-borne metalloid was soluble in the different soils resulting in Sb soil solution concentration (10.75 ± 0.52 μg L(-1)) that could present concern for contamination of water resources. EDTA proved a poor predictor of As and Sb phytoavailability. Oral bioaccessibility, as measured by SBET, was risk from soil borne As and Sb in the floodplain environment.

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

    International Nuclear Information System (INIS)

    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 124Sb 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)

  19. One-step synthesis of antimony-doped tin dioxide nanocrystallites and their property

    Institute of Scientific and Technical Information of China (English)

    ZHENG Min; WANG Bao

    2009-01-01

    Antimony-doped tin dioxide(ATO) nanoparticles with primary diameter in the range of 9-10 nm were rapidly synthesized via a novel combustion technique, starting with antimony trichloride and tin tetrachloride as metal sources and self-assembly compounds as fuels. The combustion phenomena and characteristics of products were controlled by assembling components in fuel compounds according to appropriate molar ratio. The as-synthesized products were characterized by XRD, SEM, TEM and XPS, respectively. The electrical conductivity was evaluated through measuring the antistatic property of polyester fiber treated by the as-synthesized products. The results show that a mild combustion phenomena without release of smoke can be taken on and perfect azury rutile ATO crystal with complete substitution can be formed rapidly under the appropriate synthetic conditions. The antistatic property of the polyester fiber treated by the as-synthesized ATO products is enhanced remarkably. The triboelectricity voltage below 1.0 kV, half life below 1.0 s and surface resistance below 1.0×106 Ω can be attained.

  20. 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.

  1. 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.

  2. Progress of Antimony-containing Wastewater Treatment%含锑废水处理技术研究进展

    Institute of Scientific and Technical Information of China (English)

    尹鑫; 周广柱; 王翠珍; 王世豪; 彭刚; 何双

    2014-01-01

    在锑矿的开采及冶炼加工过程中,排出了大量含锑废水,这种重金属废水对环境和人体健康构成严重威胁。本文总结了重金属锑元素的物理化学性质、毒性特点,归纳了含锑废水的处理方法,分析了含锑废水处理技术的优势和缺点,提出了工艺联合应用等高效处理含锑废水的相关建议。%A large amount of wastewater containing antimony discharged in the process of antimony ore mining,smelting and processing,which pose a serious threat to the environment and human health. In this paper we summarized the characteristics of physical and chemical properties, toxicity of antimony, and the antimony wastewater treatment. Advantages and disadvantages of these treatment crafts were compared in a table,the recommendations given out for more efficiently processing via crafts combination.

  3. Electrochemical, structural and surface characterization of nickel/zirconia solid oxide fuel cell anodes in coal gas containing antimony

    Science.gov (United States)

    Marina, Olga A.; Pederson, Larry R.; Coyle, Christopher A.; Thomsen, Edwin C.; Nachimuthu, Ponnusamy; Edwards, Danny J.

    The interactions of antimony with the nickel-zirconia anode in solid oxide fuel cells (SOFCs) have been investigated. Tests with both anode-supported and electrolyte-supported button cells were performed at 700 and 800 °C in synthetic coal gas containing 100 ppb to 9 ppm antimony. Minor performance loss was observed immediately after Sb introduction to coal gas resulting in ca. 5% power output drop. While no further degradation was observed during the following several hundred hours of testing, cells abruptly and irreversibly failed after 800-1600 h depending on Sb concentration and test temperature. Antimony was found to interact strongly with nickel resulting in extensive alteration phase formation, consistent with expectations based on thermodynamic properties. Nickel antimonide phases, NiSb and Ni 5Sb 2, were partially coalesced into large grains and eventually affected electronic percolation through the anode support. Initial degradation was attributed to diffusion of antimony to the active anode/electrolyte interface to form an adsorption layer, while the late stage degradation was due the Ni-Sb phase formation. Assuming an average Sb concentration in coal gas of 0.07 ppmv, a 500 μm thick Ni/zirconia anode-supported cell is not expected to fail within 7 years when operated at a power output of 0.5 W cm -2 and fuel utilization above 50%.

  4. 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, Andre 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 d

  5. POLICY China’s Ministry of Commerce Set the Rules for Antimony and Tungsten Export in 2005

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    <正> China’s ministry of commerce recently re-leased the rules and application procedures forthe export of antimony and tungsten productsin 2005 by the domestic producers.Based on the rules set by the ministry,China’santimony and tungsten producers providingtheir products for export must be those enter-prises authorized by the related State authori-ties.

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

    NARCIS (Netherlands)

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

    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. Stu

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

    Science.gov (United States)

    Pimentel, Maria Inês Fernandes; Baptista, Cibele; Rubin, Evelyn Figueiredo; Vasconcellos, Erica de Camargo Ferreira e; Lyra, Marcelo Rosandiski; Salgueiro, Mariza de Matos; Saheki, Maurício Naoto; Rosalino, Cláudia Maria Valete; Madeira, Maria de Fátima; Silva, Aline Fagundes da; Confort, Eliame Mouta; Schubach, Armando de Oliveira

    2011-01-01

    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 4 mg/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. PMID:21552747

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

    Science.gov (United States)

    Pimentel, Maria Inês Fernandes; Baptista, Cibele; Rubin, Evelyn Figueiredo; Vasconcellos, Erica de Camargo Ferreira e; Lyra, Marcelo Rosandiski; Salgueiro, Mariza de Matos; Saheki, Maurício Naoto; Rosalino, Cláudia Maria Valete; Madeira, Maria de Fátima; Silva, Aline Fagundes da; Confort, Eliame Mouta; Schubach, Armando de Oliveira

    2011-01-01

    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 4 mg/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.

  9. Synthesis and characterization of (Ni1-xCox)Se2 based ternary selenides as electrocatalyst for triiodide reduction in dye-sensitized solar cells

    Science.gov (United States)

    Theerthagiri, J.; Senthil, R. A.; Buraidah, M. H.; Raghavender, M.; Madhavan, J.; Arof, A. K.

    2016-06-01

    Ternary metal selenides of (Ni1-xCox)Se2 with 0≤x≤1 were synthesized by using one-step hydrothermal reduction route. The synthesized metal selenides were utilized as an efficient, low-cost platinum free counter electrode for dye-sensitized solar cells. The cyclic voltammetry and electrochemical impedance spectroscopy studies revealed that the Ni0.5Co0.5Se2 counter electrode exhibited higher electrocatalytic activity and lower charge transfer resistance at the counter electrode/electrolyte interface than the other compositions for reduction of triiodide to iodide. Ternary selenides of Ni0.5Co0.5Se2 offer a synergistic effect to the electrocatalytic activity for the reduction of triiodide that might be due to an increase in active catalytic sites and small charge transfer resistance. The DSSC with Ni0.5Co0.5Se2 counter electrode achieved a high power conversion efficiency of 6.02%, which is comparable with that of conventional platinum counter electrode (6.11%). This present investigation demonstrates the potential application of Ni0.5Co0.5Se2 as counter electrode in dye-sensitized solar cells.

  10. Determination of natural isotopic variation in antimony using inductively coupled plasma mass spectrometry for an uncertainty estimation of the standard atomic weight of antimony

    International Nuclear Information System (INIS)

    The isotopic variation of industrially produced antimony was estimated using multiple-collector inductively coupled plasma mass spectrometry. A reproducible 123Sb/121Sb ratio of ±0.004% (2 standard deviations) was routinely obtained using a Sn doping mass discrimination correction technique. Only a small isotopic variation of about 0.05% was observed among industrially important Sb materials (five commercially available reagents and two ore minerals). The degree of Sb isotopic variation to determine the uncertainty in Sb atomic weight can be reduced by this new analytical technique to 0.00025 compared to the currently accepted IUPAC isotopic variation determined by conventional mass spectrometry of ±0.001. Heavy isotope enrichment of Sb in a drainage water sample from a stibnite mining area was found. This heavy isotope enrichment tendency in an aqueous environment may be useful in detecting anthropogenic Sb input from industrial emission by the smelting process via air because Sb of anthropogenic origin will have lighter isotope enrichment features. (author)

  11. First-Principles Study of Antimony Doping Effects on the Iron-Based Superconductor CaFe(SbxAs1-x)2

    Science.gov (United States)

    Nagai, Yuki; Nakamura, Hiroki; Machida, Masahiko; Kuroki, Kazuhiko

    2015-09-01

    We study antimony doping effects on the iron-based superconductor CaFe(SbxAs1-x)2 by using the first-principles calculation. The calculations reveal that the substitution of a doped antimony atom into As of the chainlike As layers is more stable than that into FeAs layers. This prediction can be checked by experiments. Our results suggest that doping homologous elements into the chainlike As layers, which only exist in the novel 112 system, is responsible for rising up the critical temperature. We discuss antimony doping effects on the electronic structure. It is found that the calculated band structures with and without the antimony doping are similar to each other within our framework.

  12. Phytoavailability of antimony and heavy metals in arid regions: the case of the Wadley Sb district (San Luis, Potosí, Mexico).

    Science.gov (United States)

    Levresse, G; Lopez, G; Tritlla, J; López, E Cardellach; Chavez, A Carrillo; Salvador, E Mascuñano; Soler, A; Corbella, M; Sandoval, L G Hernández; Corona-Esquivel, R

    2012-06-15

    This paper presents original results on the Sb and heavy metals contents in sediments and waste tailings, plants and water from the giant Wadley antimony mine district (San Luis Potosí State, Mexico). The dominant antimony phases in mining wastes are stibiconite, montroydite and minor hermimorphite. The waste tailings contain high concentrations of metals and metalloids (antimony, iron, zinc, arsenic, copper, and mercury). Manganese, copper, zinc, and antimony contents exceed the quality guidelines values for groundwater, plants and for waste tailings. Results indicate that peak accumulation is seasonal due to the concentration by high metabolism plants as Solanaceae Nicotiana. The metal phytoavailability in waste tailings is highly dependant on the metal speciation, its capability to be transported in water and, more particularly, the plant metabolism efficiency.

  13. Thermoelectric transport in surface- and antimony-doped bismuth telluride nanoplates

    Science.gov (United States)

    Pettes, Michael Thompson; Kim, Jaehyun; Wu, Wei; Bustillo, Karen C.; Shi, Li

    2016-10-01

    We report the in-plane thermoelectric properties of suspended (Bi1-xSbx)2Te3 nanoplates with x ranging from 0.07 to 0.95 and thicknesses ranging from 9 to 42 nm. The results presented here reveal a trend of increasing p-type behavior with increasing antimony concentration, and a maximum Seebeck coefficient and thermoelectric figure of merit at x ˜ 0.5. We additionally tuned extrinsic doping of the surface using a tetrafluoro-tetracyanoquinodimethane (F4-TCNQ) coating. The lattice thermal conductivity is found to be below that for undoped ultrathin Bi2Te3 nanoplates of comparable thickness and in the range of 0.2-0.7 W m-1 K-1 at room temperature.

  14. Nuclear quadrupole resonance of iodine pentafluoride and its complexes with antimony pentafluoride

    International Nuclear Information System (INIS)

    The spectra of nuclear quadrupole resonance (NQR) have been obtained at 77 deg K for I127 and Sbsup(121,128) in the IF5, IF5xSbF5, IF5x2SbF5, CsIF6, and RbIF6 compounds. An agreement between quadrupole spectra and structural data have been observed. The results of studying IF5 by NQR, gamma resonance and microwave spectroscopy have been compared. It has been established that unshared electron pair of an iodine atom is stereochemically active which leads to a considerable distortion of octahedral symmetry of coordination polyhedron of the iodine atoms. The structure of complexes of iodine pentafluoride with antimony pentafluoride is given

  15. A novel composite material based on antimony(III) oxide and amorphous silica

    Energy Technology Data Exchange (ETDEWEB)

    Zemnukhova, Ludmila A. [Institute of Chemistry, Far-Eastern Branch, Russian Academy of Sciences, 690022 Vladivostok (Russian Federation); Panasenko, Alexander E., E-mail: panasenko@ich.dvo.ru [Institute of Chemistry, Far-Eastern Branch, Russian Academy of Sciences, 690022 Vladivostok (Russian Federation)

    2013-05-01

    The composite material nSb₂O₃·mSiO₂·xH₂O was prepared by hydrolysis of SbCl₃ and Na₂SiO₃ in an aqueous medium. It has been shown that the composition of the material is influenced by the ratio of the initial components and the acidity of the reaction medium. The morphology of the material particles and its specific surface area have been determined. The thermal and optic properties were also investigated. - Graphical abstract: Novel composite material containing amorphous silica and crystal antimony(III) oxide has been synthesized by hydrolysis of SbCl₃ and Na₂SiO₃ in an aqueous medium. Highlights: • The composite material nSb₂O₃·mSiO₂·xH₂O was prepared in an aqueous medium. • The composition of the material is controllable by a synthesis conditions. • The morphology of the material and its optic properties have been determined.

  16. Preparation and characterization of conductive antimony-doped tin oxide (ATO) nanoparticles

    Institute of Scientific and Technical Information of China (English)

    LIN; Feng; DUAN; Xue-chen; REN; Xian-jing

    2005-01-01

    In this paper, conductive antimony-doped tin oxide (ATO) composite particles is prepared by hydroxylation method of metal alcoxides. This method has many advantages such as little pollution, low cost, simple sheet and equipment. The synthesis processing and the ATO nanoparticles are characterized by means of transmission electron microscope (TEM), X-ray diffraction (XRD), thermal gravimetric and differential thermal analysis, and BET. The results show that the ATO nanoparticles is tetragonal rutile crystal structure. TEM show that the particles are monodispersed with weak aggromation. The size of the particles calcinated at 700 is about 8nm. The specific areas are 153 m2 · g-1. In addition to, ATO nanop articles have good electric properties

  17. Sequential solvent extraction for forms of antimony in five selected coals

    Science.gov (United States)

    Qi, C.; Liu, Gaisheng; Kong, Y.; Chou, C.-L.; Wang, R.

    2008-01-01

    Abundance of antimony in bulk samples has been determined in five selected coals, three coals from Huaibei Coalfield, Anhui, China, and two from the Illinois Basin in the United States. The Sb abundance in these samples is in the range of 0.11-0.43 ??g/g. The forms of Sb in coals were studied by sequential solvent extraction. The six forms of Sb are water soluble, ion changeable, organic matter bound, carbonate bound, silicate bound, and sulfide bound. Results of sequential extraction show that silicate-bound Sb is the most abundant form in these coals. Silicate- plus sulfide-bound Sb accounts for more than half of the total Sb in all coals. Bituminous coals are higher in organic matterbound Sb than anthracite and natural coke, indicating that the Sb in the organic matter may be incorporated into silicate and sulfide minerals during metamorphism. ?? 2008 by The University of Chicago. All rights reserved.

  18. Reduced Graphene Oxide/Tin-Antimony Nanocomposites as Anode Materials for Advanced Sodium-Ion Batteries.

    Science.gov (United States)

    Ji, Liwen; Zhou, Weidong; Chabot, Victor; Yu, Aiping; Xiao, Xingcheng

    2015-11-11

    Reduced graphene oxides loaded with tin-antimony alloy (RGO-SnSb) nanocomposites were synthesized through a hydrothermal reaction and the subsequent thermal reduction treatments. Transmission electron microscope images confirm that SnSb nanoparticles with an average size of about 20-30 nm are uniformly dispersed on the RGO surfaces. When they were used as anodes for rechargeable sodium (Na)-ion batteries, these as-synthesized RGO-SnSb nanocomposite anodes delivered a high initial reversible capacity of 407 mAh g(-1), stable cyclic retention for more than 80 cycles and excellent cycle stability at ultra high charge/discharge rates up to 30C. The significantly improved performance of the synthesized RGO-SnSb nanocomposites as Na-ion battery anodes can be attributed to the synergetic effects of RGO-based flexible framework and the nanoscale dimension of the SnSb alloy particles (batteries.

  19. 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.

  20. Novel fabrication of an electrochromic antimony-doped tin oxide film using a nanoparticle deposition system

    Science.gov (United States)

    Kim, Hyungsub; Park, Yunchan; Choi, Dahyun; Ahn, Sung-Hoon; Lee, Caroline Sunyong

    2016-07-01

    Novel deposition method of Antimony-doped tin oxide (ATO) thin films was introduced using a nanoparticle deposition system (NPDS) to fabricate an electrochromic (EC) device. NPDS is a dry deposition method that simplifies the ATO deposition process by eliminating the need for solvents or binders. In this study, an ATO EC layer was deposited using NPDS. The surface morphology and electrochemical and optical transmittance properties were characterized. The optical transmittance change in the ATO EC device was ∼35% over the wavelength range of 350-800 nm, and the cyclic transmittance was stable. The ATO film deposited using NPDS, exhibited a coloration efficiency of 15.5 cm2 C-1. Therefore, our results suggest that ATO EC devices can be fabricated using a simple, cost-effective NPDS, which allows nanoparticles to be deposited directly without pre- or post-processing.

  1. 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. PMID:27188777

  2. Properties of antimony doped ZnO thin films deposited by spray pyrolysis technique

    Energy Technology Data Exchange (ETDEWEB)

    Sadananda Kumar, N., E-mail: sadanthara@gmail.com; Bangera, Kasturi V.; Shivakumar, G. K. [National Institute of Technology Karnataka, Surathkal, Thin Films Laboratory, Department of Physics (India)

    2015-07-15

    Antimony (Sb) doped zinc oxide (ZnO) thin films were deposited on the glass substrate at 450°C using spray pyrolysis technique. Effect of Sb doping on surface morphology structural, optical and electrical properties were studied. X-ray diffraction (XRD) analysis showed that both the undoped and doped ZnO thin films are polycrystalline in nature with (101) preferred orientation. SEM analysis showed a change in surface morphology of Sb doped ZnO thin films. Doping results in a marked increase in conductivity without affecting the transmittance of the films. ZnO films prepared with 3 at % Sb shows the lowest resistivity of 0.185 Ohm cm with a Hall mobility of 54.05 cm{sup 2} V{sup –1} s{sup –1}, and a hole concentration of 6.25 × 10{sup 17} cm{sup –3}.

  3. Renal function evaluation in patients with American Cutaneous Leishmaniasis after specific treatment with pentavalent antimonial

    Directory of Open Access Journals (Sweden)

    Oliveira Rodrigo A

    2012-06-01

    Full Text Available Abstract Background Renal evaluation studies are rare in American Cutaneous Leishmaniasis (ACL. The aim of this study is to investigate whether specific treatment reverts ACL-associated renal dysfunction. Methods A prospective study was conducted with 37 patients with ACL. Urinary concentrating and acidification ability was assessed before and after treatment with pentavalent antimonial. Results The patients mean age was 35.6 ± 12 years and 19 were male. Before treatment, urinary concentrating defect (U/Posm Conclusion As previously described, urinary concentrating and acidification defects were found in an important number of patients with ACL. Present results demonstrate that only some patients recover urinary acidification capacity, while no one returned to normal urinary concentration capacity.

  4. Supermolecular template route to fabrication of well crystallized hollow antimony microspheres

    Institute of Scientific and Technical Information of China (English)

    GU Li; CHEN Shu-da; WEI Xiao-yan

    2006-01-01

    Hollow spheres of elemental antimony (Sb) with good crystallinity, high contrast and thin wall were prepared in the solutions of poly(ethylene glycol) (PEG) and oleic acid(OA) associations at the refluxed temperature. The complexes of Sb3+ with tartaric acid were used as precursors, which can avoid the hydrolysis of SbCl3 and the resulting impurity of products. The average diameter and thickness of the as-prepared hollow sphere are about 300 nm and less than 20 nm, respectively. The formation of hollow spheres depends on the template function of PEG and OA associations, which can be confirmed through the theoretical analysis and results of control experiments. The specific surface area reaches 34.669 m2/g.

  5. 锑环境健康效应的研究进展%Environmental Health Effect of Antimony: a Review of Recent Researches

    Institute of Scientific and Technical Information of China (English)

    戈兆凤; 韦朝阳

    2011-01-01

    随着锑的开采及含锑产品的广泛应用,锑所带来的污染问题已越来越严重,锑对环境与健康的危害也受到了更多的关注.该文总结了锑环境健康效应的研究进展,从医学、环境毒理学和生态毒理学的角度分别分析了锑对人、动物以及植物与土壤生物的健康效应.提示今后还需加强锑的致癌性及基因毒性研究,并需从微观与宏观尺度揭示锑的毒性效应,以期为锑的环境健康风险评估提供科学依据.%The antimony mining and widely use of antimony products have resulted in serious antimony contamination,causing hazards to both the environment and human health. The present paper summarized the research progresses on the environmental health effect of antimony. The health effects of antimony on human, animals, and plants as well as soil organisms are introduced and discussed in the view of medical science, environmental toxicology and ecological toxicology, respectively. It is suggested that more researches should be conducted on antimony earcinogenieity and genotoxicity, and the toxic effects of antimony should be explored from micro and macroscopic scales in order to provide the scientific basis for risk assessment of antimony.

  6. 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.

  7. Infrared-to-red upconversion luminescence in samarium-doped antimony glasses

    International Nuclear Information System (INIS)

    A new antimony-based glass system (K2O-B2O3-Sb2O3) having low phonon energy (about 600 cm-1) doped with Sm3+ ions has been developed. Infrared reflection spectroscopic (IRRS) studies have been employed to establish its low phonon energy. Ultraviolet-Visible-near infrared (UV-Vis-NIR) absorption and photoluminescence upconversion properties with the spectrochemistry of the 15K2O-15B2O3-70Sb2O3 (mol%) glasses have been studied doping with different concentrations (0.1-1.0 wt%) of Sm2O3. UV-Vis-NIR absorption band positions have been justified with quantitative calculation of nephelauxetic parameter and covalent bonding characteristics of the host. NIR to visible upconversion has been investigated by exciting at 949 nm at room temperature. Three upconverted bands originating from the 4G5/2→6H5/2, 4G5/2→6H7/2 and 4G5/2→6H9/2 transitions are found to be centered at 566 (green, weak), 602 (orange, weak) and 636 (red, remarkably strong) nm, respectively. These bands have been explained from the evaluation of the absorption, normal (downconversion) fluorescence and excitation spectra. The upconversion processes have been explained by the excited state absorption (ESA), energy transfer (ET) and cross-relaxation (CR) mechanisms involving population of the metastable (storage) energy level (4G5/2) by multiphonon deexcitation effect. It is evident from the IRRS study that the upconversion phenomena are expedited by the low multiphonon relaxation rate in antimony glasses owing to their low phonon energy (602 cm-1, the main and highest intensity Sb-O-Sb stretching band) which is very close to that of fluoride glasses (500-600 cm-1)

  8. Optical properties of Eu3+-doped antimony-oxide-based low phonon disordered matrices

    Science.gov (United States)

    Som, Tirtha; Karmakar, Basudeb

    2010-01-01

    A new series of monolithic Eu2O3-doped high antimony oxide (40-80 mol%) content disordered matrices (glasses) of low phonon energy (about 600 cm-1) in the K2O-B2O3-Sb2O3 (KBS) system was prepared by the melt-quench technique. Infrared reflection spectroscopy was used to establish the low phonon energy of the glasses. Amorphicity and devitrification of the glasses were confirmed by x-ray diffraction analysis. UV-vis absorption spectra of Eu3+ have been measured and the band positions have been justified with quantitative calculation of the nephelauxetic parameter and covalent bonding characteristics of the host. These Eu2O3-doped glasses upon excitation at 393 nm radiation exhibit six emission bands in the range 500-750 nm due to their low phonon energy. Of these, the magnetic dipole ^{5}\\mathrm {D}_{0} \\to {}^{7} \\mathrm {F_{1}} transition shows small Stark splitting while the electric dipole ^{5}\\mathrm {D}_{0} \\to {}^{7}\\mathrm {F}_{2} transition undergoes remarkable Stark splitting into two components. They have been explained by the crystal field effect. The Judd-Ofelt parameters, Ωt = 2,4,6, were also evaluated and the change of Ωt with the glass composition was correlated with the asymmetric effect at Eu3+ ion sites and the fundamental properties like covalent character and optical basicity. We are the first to report the spectroscopic properties of the Eu3+ ion in KBS low phonon antimony glasses.

  9. Optical characterization of antimony-based bismuth-doped thin films with different annealing temperatures

    Institute of Scientific and Technical Information of China (English)

    Xinmiao Lu; Yiqun Wu; Yang Wang; Jinsong Wei

    2011-01-01

    Antimony-b ased bismuth-doped thin film,a new kind of super-resolution mask layer,is prepared by magnetron sputtering.The structures and optical constants of the thin films before and after annealing are examined in detail.The as-deposited film is mainly in an amorphous state.After annealing at 170-370℃,it is converted to the rhombohedral-type of structure.The extent of crystallization increased with the annealing temperature.When the thin film is annealed,its refractive index decreased in the most visible region,whereas the extinction coefficient and reflectivity are markedly increased.The results indicate that the optical parameters of the film strongly depend on its microstructure and the bonding of the atoms.As demand for ultrahigh-density information storage continues to grow the recording mark size in optical memory is reduced to the nanometer scale [1- 4].Exceeding the optical diffraction limit with traditional optical storage technology has become a challenge[5-6].%Antimony-based bismuth-doped thin film, a new kind of super-resolution mask layer, is prepared by magnetron sputtering. The structures and optical constants of the thin films before and after annealing are examined in detail. The as-deposited film is mainly in an amorphous state. After annealing at 170-370℃, it is converted to the rhombohedral-type of structure. The extent of crystallization increased with the annealing temperature. When the thin film is annealed, its refractive index decreased in the most visible region, whereas the extinction coefficient and reflectivity are markedly increased. The results indicate that the optical parameters of the film strongly depend on its microstructure and the bonding of the atoms.

  10. Decreased antimony uptake and overexpression of genes of thiol metabolism are associated with drug resistance in a canine isolate of Leishmania infantum.

    Science.gov (United States)

    Gómez Pérez, Verónica; García-Hernandez, Raquel; Corpas-López, Victoriano; Tomás, Ana M; Martín-Sanchez, Joaquina; Castanys, Santiago; Gamarro, Francisco

    2016-08-01

    Visceral leishmaniasis (VL) caused by the protozoan parasite Leishmania infantum, is one of the most important zoonotic diseases affecting dogs and humans in the Mediterranean area. The presence of infected dogs as the main reservoir host of L. infantum is regarded as the most significant risk for potential human infection. We have studied the susceptibility profile to antimony and other anti-leishmania drugs (amphotericin B, miltefosine, paromomycin) in Leishmania infantum isolates extracted from a dog before and after two therapeutic interventions with meglumine antimoniate (subcutaneous Glucantime(®), 100 mg/kg/day for 28 days). After the therapeutic intervention, these parasites were significantly less susceptible to antimony than pretreatment isolate, presenting a resistance index of 6-fold to Sb(III) for promastigotes and >3-fold to Sb(III) and 3-fold to Sb(V) for intracellular amastigotes. The susceptibility profile of this resistant L. infantum line is related to a decreased antimony uptake due to lower aquaglyceroporin-1 expression levels. Additionally, other mechanisms including an increase in thiols and overexpression of enzymes involved in thiol metabolism, such as ornithine decarboxylase, trypanothione reductase, mitochondrial tryparedoxin and mitochondrial tryparedoxin peroxidase, could contribute to the resistance as antimony detoxification mechanisms. A major contribution of this study in a canine L. infantum isolate is to find an antimony-resistant mechanism similar to that previously described in other human clinical isolates. PMID:27317865

  11. Ecotoxicological assessment of solar cell leachates: Copper indium gallium selenide (CIGS) cells show higher activity than organic photovoltaic (OPV) cells.

    Science.gov (United States)

    Brun, Nadja Rebecca; Wehrli, Bernhard; Fent, Karl

    2016-02-01

    Despite the increasing use of photovoltaics their potential environmental risks are poorly understood. Here, we compared ecotoxicological effects of two thin-film photovoltaics: established copper indium gallium selenide (CIGS) and organic photovoltaic (OPV) cells. Leachates were produced by exposing photovoltaics to UV light, physical damage, and exposure to environmentally relevant model waters, representing mesotrophic lake water, acidic rain, and seawater. CIGS cell leachates contained 583 μg L(-1) molybdenum at lake water, whereas at acidic rain and seawater conditions, iron, copper, zinc, molybdenum, cadmium, silver, and tin were present up to 7219 μg L(-1). From OPV, copper (14 μg L(-1)), zinc (87 μg L(-1)) and silver (78 μg L(-1)) leached. Zebrafish embryos were exposed until 120 h post-fertilization to these extracts. CIGS leachates produced under acidic rain, as well as CIGS and OPV leachates produced under seawater conditions resulted in a marked hatching delay and increase in heart edema. Depending on model water and solar cell, transcriptional alterations occurred in genes involved in oxidative stress (cat), hormonal activity (vtg1, ar), metallothionein (mt2), ER stress (bip, chop), and apoptosis (casp9). The effects were dependent on the concentrations of cationic metals in leachates. Addition of ethylenediaminetetraacetic acid protected zebrafish embryos from morphological and molecular effects. Our study suggests that metals leaching from damaged CIGS cells, may pose a potential environmental risk.

  12. An approach to global rovibrational analysis based on anharmonic ladder operators: Application to Hydrogen Selenide (H280Se)

    International Nuclear Information System (INIS)

    Graphical abstract: Schematic diagram of a bent triatomic molecule, depicting the atom numbering, and molecular axis system. An algebraic approach to perform global rovibrational analysis is presented. Highlights: ► Novel approach for a global rovibrational analysis of polyatomic molecules spectra. ► One-dimensional vibron model limit combined with rotational degrees of freedom. ► Phase space Hamiltonian written in terms of anharmonic ladder operators. ► Algebraic calculations performed with a symmetry-adapted rovibrational basis. ► Description of the rovibrational spectrum of H2Se in the ground electronic state. - Abstract: An algebraic approach to perform global rovibrational analysis of molecular spectra is presented. The approach combines the one-dimensional limit of the vibron model with rotational degrees of freedom. The model is based on the expression of the phase space Hamiltonian in terms of anharmonic ladder operators and the use of a symmetry-adapted basis set given by the linear combination of products of local vibrational and rotational wavefunctions. As an example we model the rovibrational spectra of a bent triatomic molecule, providing a global analysis for vibrational bands up to polyad 12 and Jmax = 5 of Hydrogen Selenide (H2Se). Satisfactory fits of vibrational and rovibrational energies are obtained. A prediction of 2579 rovibrational energies up to J ⩽ 5 and polyad 12 for the 140 lowest vibrational bands is also obtained. A possible extension of the model to reach spectroscopic quality results in larger molecular systems is also given.

  13. Structural and Optical Studies of 100 MeV Ni+7 Irradiated Cadmium Selenide Thin Films

    Directory of Open Access Journals (Sweden)

    Rajesh Singh

    2015-10-01

    Full Text Available The effect of irradiation with Swift (100 MeV Ni+ 7 ions on the structural and optical properties of Cadmium Selenide (CdSe thin films have been investigated at different fluencies in the range of 1  1011-1  1013 ions/cm – 2. The CdSe films on glass substrates were prepared by thermal evaporation. The structural and optical changes with respect to increasing fluence were observed by the means of X-ray diffraction (XRD, UV-VIS and Raman spectroscopy. After irradiating the films with Ni+ 7 ions XRD show the increased in peak intensity and crystallite size with increasing fluence. The UV-VIS-IR spectroscopy revealed that there is decrease in band gap energy of the films after irradiation with increasing fluencies. Raman spectrum for as deposited and irradiated films show two peak, one at 209 cm – 1 and at 410 cm – 1 which is assigned to the longitudinal optical (LO phonon mode.

  14. Transition from Sign-Reversed to Sign-Preserved Cooper-Pairing Symmetry in Sulfur-Doped Iron Selenide Superconductors

    Science.gov (United States)

    Wang, Qisi; Park, J. T.; Feng, Yu; Shen, Yao; Hao, Yiqing; Pan, Bingying; Lynn, J. W.; Ivanov, A.; Chi, Songxue; Matsuda, M.; Cao, Huibo; Birgeneau, R. J.; Efremov, D. V.; Zhao, Jun

    2016-05-01

    An essential step toward elucidating the mechanism of superconductivity is to determine the sign or phase of the superconducting order parameter, as it is closely related to the pairing interaction. In conventional superconductors, the electron-phonon interaction induces attraction between electrons near the Fermi energy and results in a sign-preserved s -wave pairing. For high-temperature superconductors, including cuprates and iron-based superconductors, prevalent weak coupling theories suggest that the electron pairing is mediated by spin fluctuations which lead to repulsive interactions, and therefore that a sign-reversed pairing with an s± or d -wave symmetry is favored. Here, by using magnetic neutron scattering, a phase sensitive probe of the superconducting gap, we report the observation of a transition from the sign-reversed to sign-preserved Cooper-pairing symmetry with insignificant changes in Tc in the S-doped iron selenide superconductors KxFe2 -y(Se1-zSz) 2 . We show that a rather sharp magnetic resonant mode well below the superconducting gap (2 Δ ) in the undoped sample (z =0 ) is replaced by a broad hump structure above 2 Δ under 50% S doping. These results cannot be readily explained by simple spin fluctuation-exchange pairing theories and, therefore, multiple pairing channels are required to describe superconductivity in this system. Our findings may also yield a simple explanation for the sometimes contradictory data on the sign of the superconducting order parameter in iron-based materials.

  15. Temperature anomaly of the coefficient of ultrasonic absorption by electrons of hybridized states of cobalt impurities in mercury selenide

    Science.gov (United States)

    Zhevstovskikh, I. V.; Okulov, V. I.; Gudkov, V. V.; Mayakin, V. Yu.; Sarychev, M. N.; Andriichuk, M. D.; Paranchich, L. D.

    2015-05-01

    The effects of the interaction of ultrasound with donor d electrons of cobalt impurity atoms at low concentrations in mercury selenide crystals have been investigated. The temperature dependences of the electronic contribution to the absorption coefficient at a frequency of 53 MHz in crystals with cobalt concentrations from 1018 to 1020 cm-3 and in the undoped crystal have been observed experimentally. It has been found that crystals with impurities are characterized by an anomalous nonmonotonic temperature dependence of the absorption coefficient of the slow transverse wave in a narrow temperature range near 10 K. A smooth monotonic temperature dependence has been observed for longitudinal and fast transverse waves. Based on the developed theoretical interpretation, it has been established that the anomaly in the temperature dependence of the absorption coefficient of a slow transverse wave is associated with the hybridization of impurity d states in the conduction band of the crystal. A comparison of the theoretical and experimental dependences has made it possible to determine the parameters characterizing the hybridized electronic states.

  16. Influence of growth and photocatalytic properties of copper selenide (CuSe) nanoparticles using reflux condensation method

    Science.gov (United States)

    Sonia, S.; Kumar, P. Suresh; Mangalaraj, D.; Ponpandian, N.; Viswanathan, C.

    2013-10-01

    Influence of reaction conditions on the synthesis of copper selenide (CuSe) nanoparticles and their photo degradation activity is studied. Nearly monodispersed uniform size (23-44 nm) nanoparticles are synthesized by varying the reaction conditions using reflux condensation method. The obtained nanoparticles are characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy and UV-visible absorption spectroscopy. The X-ray diffraction analysis of the sample shows the formation of nanoparticles with hexagonal CuSe structure. The result indicates that on increasing the reaction time from 4 to 12 h, the particle size decreases from 44 to 23 nm, but an increase in the reaction temperature increases the particle size. The calculated band gap Eg is ranging from 2.34 to 3.05 eV which is blue shifted from the bulk CuSe (2.2 eV). The photocatalytic degradation efficiency of the CuSe nanoparticles on two organic dyes Methylene blue (MB) and Rhodamine-B (RhB) in aqueous solution under UV region is calculated as 76 and 87% respectively.

  17. Selenide isotope generator for the Galileo Mission: copper/water axially-grooved heat pipe topical report

    Energy Technology Data Exchange (ETDEWEB)

    Strazza, N.P.

    1979-06-30

    This report presents a summary of the major accomplishments for the development, fabrication, and testing of axially-grooved copper/water heat pipes for Selenide Isotopic Generator (SIG) applications. The early development consisted of chemical, physical, and analytical studies to define an axially-grooved tube geometry that could be successfully fabricated and provide the desired long term (up to seven years) performance is presented. Heat pipe fabrication procedures, measured performance and accelerated life testing of heat pipes S/Ns AL-5 and LT-57 conducted at B and K Engineering are discussed. S/N AL-5 was the first axially-grooved copper/water heat pipe that was fabricated with the new internal coating process for cupric oxide (CuO) and the cleaning and water preparation methods developed by Battelle Columbus Laboratories. Heat pipe S/N LT-57 was fabricated along with sixty other axially-grooved heat pipes allocated for life testing at Teledyne Energy Systems. As of June 25, 1979, heat pipes S/Ns AL-5 and LT-57 have been accelerated life tested for 13,310 and 6,292 respectively, at a nominal operating temperature of 225/sup 0/C without any signs of thermal performance degradation. (TFD)

  18. Ecotoxicological assessment of solar cell leachates: Copper indium gallium selenide (CIGS) cells show higher activity than organic photovoltaic (OPV) cells.

    Science.gov (United States)

    Brun, Nadja Rebecca; Wehrli, Bernhard; Fent, Karl

    2016-02-01

    Despite the increasing use of photovoltaics their potential environmental risks are poorly understood. Here, we compared ecotoxicological effects of two thin-film photovoltaics: established copper indium gallium selenide (CIGS) and organic photovoltaic (OPV) cells. Leachates were produced by exposing photovoltaics to UV light, physical damage, and exposure to environmentally relevant model waters, representing mesotrophic lake water, acidic rain, and seawater. CIGS cell leachates contained 583 μg L(-1) molybdenum at lake water, whereas at acidic rain and seawater conditions, iron, copper, zinc, molybdenum, cadmium, silver, and tin were present up to 7219 μg L(-1). From OPV, copper (14 μg L(-1)), zinc (87 μg L(-1)) and silver (78 μg L(-1)) leached. Zebrafish embryos were exposed until 120 h post-fertilization to these extracts. CIGS leachates produced under acidic rain, as well as CIGS and OPV leachates produced under seawater conditions resulted in a marked hatching delay and increase in heart edema. Depending on model water and solar cell, transcriptional alterations occurred in genes involved in oxidative stress (cat), hormonal activity (vtg1, ar), metallothionein (mt2), ER stress (bip, chop), and apoptosis (casp9). The effects were dependent on the concentrations of cationic metals in leachates. Addition of ethylenediaminetetraacetic acid protected zebrafish embryos from morphological and molecular effects. Our study suggests that metals leaching from damaged CIGS cells, may pose a potential environmental risk. PMID:26615488

  19. Selenide isotope generator for the Galileo Mission: copper/water axially-grooved heat pipe topical report

    International Nuclear Information System (INIS)

    This report presents a summary of the major accomplishments for the development, fabrication, and testing of axially-grooved copper/water heat pipes for Selenide Isotopic Generator (SIG) applications. The early development consisted of chemical, physical, and analytical studies to define an axially-grooved tube geometry that could be successfully fabricated and provide the desired long term (up to seven years) performance is presented. Heat pipe fabrication procedures, measured performance and accelerated life testing of heat pipes S/Ns AL-5 and LT-57 conducted at B and K Engineering are discussed. S/N AL-5 was the first axially-grooved copper/water heat pipe that was fabricated with the new internal coating process for cupric oxide (CuO) and the cleaning and water preparation methods developed by Battelle Columbus Laboratories. Heat pipe S/N LT-57 was fabricated along with sixty other axially-grooved heat pipes allocated for life testing at Teledyne Energy Systems. As of June 25, 1979, heat pipes S/Ns AL-5 and LT-57 have been accelerated life tested for 13,310 and 6,292 respectively, at a nominal operating temperature of 2250C without any signs of thermal performance degradation

  20. Loading of atorvastatin and linezolid in β-cyclodextrin-conjugated cadmium selenide/silica nanoparticles: A spectroscopic study.

    Science.gov (United States)

    Antony, Eva Janet; Shibu, Abhishek; Ramasamy, Sivaraj; Paulraj, Mosae Selvakumar; Enoch, Israel V M V

    2016-08-01

    The preparation of β-cyclodextrin-conjugated cadmium selenide-silica nanoparticles, the loading of two drugs viz., Atorvastatin and linezolid in the cyclodextrin cavity, and the fluorescence energy transfer between CdSe/SiO2 nanoparticles and the drugs encapsulated in the cyclodextrin cavity are reported in this paper. IR spectroscopy, X-ray diffractometry, transmission electron microscopy, and particle size analysis by light-scattering experiment were used as the tools of characterizing the size and the crystal system of the nanoparticles. The nanoparticles fall under hexagonal system. The silica-shell containing CdSe nanoparticles were functionalized by reaction with aminoethylamino-β-cyclodextrin. Fluorescence spectra of the nanoparticles in their free and drug-encapsulated forms were studied. The FÖrster distances between the encapsulated drugs and the CdSe nanoparticles are below 3nm. The change in the FÖrster resonance energy parameters under physiological conditions may aid in tracking the release of drugs from the cavity of the cyclodextrin. PMID:27157743

  1. Highly Efficient Copper-Indium-Selenide Quantum Dot Solar Cells: Suppression of Carrier Recombination by Controlled ZnS Overlayers.

    Science.gov (United States)

    Kim, Jae-Yup; Yang, Jiwoong; Yu, Jung Ho; Baek, Woonhyuk; Lee, Chul-Ho; Son, Hae Jung; Hyeon, Taeghwan; Ko, Min Jae

    2015-11-24

    Copper-indium-selenide (CISe) quantum dots (QDs) are a promising alternative to the toxic cadmium- and lead-chalcogenide QDs generally used in photovoltaics due to their low toxicity, narrow band gap, and high absorption coefficient. Here, we demonstrate that the photovoltaic performance of CISe QD-sensitized solar cells (QDSCs) can be greatly enhanced simply by optimizing the thickness of ZnS overlayers on the QD-sensitized TiO2 electrodes. By roughly doubling the thickness of the overlayers compared to the conventional one, conversion efficiency is enhanced by about 40%. Impedance studies reveal that the thick ZnS overlayers do not affect the energetic characteristics of the photoanode, yet enhance the kinetic characteristics, leading to more efficient photovoltaic performance. In particular, both interfacial electron recombination with the electrolyte and nonradiative recombination associated with QDs are significantly reduced. As a result, our best cell yields a conversion efficiency of 8.10% under standard solar illumination, a record high for heavy metal-free QD solar cells to date. PMID:26431392

  2. Sodium Antimony Gluconate Induces Generation of Reactive Oxygen Species and Nitric Oxide via Phosphoinositide 3-Kinase and Mitogen-Activated Protein Kinase Activation in Leishmania donovani-Infected Macrophages

    OpenAIRE

    Mookerjee Basu, Jayati; Mookerjee, Ananda; Sen, Prosenjit; Bhaumik, Suniti; Sen, Pradip; Banerjee, Subha; Naskar, Ksudiram; Choudhuri, Soumitra K.; Saha, Bhaskar; Raha, Sanghamitra; Roy, Syamal

    2006-01-01

    Pentavalent antimony complexes, such as sodium stibogluconate and sodium antimony gluconate (SAG), are still the first choice for chemotherapy against various forms of leishmaniasis, including visceral leishmaniasis, or kala-azar. Although the requirement of a somewhat functional immune system for the antileishmanial action of antimony was reported previously, the cellular and molecular mechanism of action of SAG was not clear. Herein, we show that SAG induces extracellular signal-regulated k...

  3. 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. PMID:27208755

  4. Obtenção de filmes espessos de seleneto de cobre sobre carbono vítreo, ouro, titânio e cobre Obtaining copper selenide thick films on vitreous carbon, gold, titanium and copper

    Directory of Open Access Journals (Sweden)

    Adriano César Rabelo

    2007-04-01

    Full Text Available Copper selenide (berzelianite films were prepared on the title substrates using the chemical bath deposition technique (CBD. Film composition was determined by energy dispersion of x-rays. The kinetics of film growth is parabolic and film adherence limits the film thickness. On titanium, copper selenide forms islands that do not completely cover the surface, unless the substrate is prepared with a tin oxide layer; film composition also depends on the titanium oxide layer. On vitreous carbon, CBD and mechanical immobilization techniques lead to films with similar resistances for the electron transfer across the film/substrate interface. On gold, composition studies revealed that film composition is always the same if the pH is in the range from 8 to 12, in contrast to films prepared by an ion-ion combination route. On copper, a new procedure for obtaining copper selenide films as thick as 5 µm has been developed.

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

    Energy Technology Data Exchange (ETDEWEB)

    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, ..delta..G/sub f,298//sup o/, ..delta..H/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 (..delta..H/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.

  6. Antimony incorporation in InAs quantum dots grown on GaAs substrate by molecular beam epitaxy

    Science.gov (United States)

    Rihani, J.; Sallet, V.; Christophe, H. J.; Oueslati, M.; Chtourou, R.

    2008-01-01

    We have grown InAs(Sb) quantum dots (QDs) on GaAs (0 0 1) substrates by molecular beam epitaxy (MBE) using two different antimony exposures ( ΦSb). Atomic force microscopy (AFM) and photoluminescence (PL) spectroscopy were carried out to investigate the dot size evolution as function of the incorporated antimony content in InAs/GaAs QDs material. Anomalous asymmetric-band feature was observed in room temperature photoluminescence (RTPL) spectra of the investigated QD samples grown at relatively high temperature (490 °C). From the temperature-dependent PL measurements, it was found that the asymmetric-band feature is associated with the ground-states transitions from QDs with bimodal size distribution. The analysis of the pump power dependent PL spectra allows us to suggest a type II band lineup for the InAsSb/GaAs QDs materials system.

  7. Interest of lymphoscintigraphy with 99sup(m)Tc-labelled antimony sulfide in the arms after breast carcinoma treatment

    International Nuclear Information System (INIS)

    2 mCi of antimony sulfide colloid labelled with sup(99m)Tc were injected subcutaneously between the digits in 25 patients with postoperative lymphoedema of the arm for breast carcinoma. The two arms are examined successively, the normal one being used as control. The lymphoscintigraphy is realised with a gamma camera during an hour. The information obtained is threefoled; on the peripheral block's importance, the place where the lymphatic flow is stopped, and the presence in 40% of patients of axillary lymph nodes. The diminution of the lymphatic flow is not in correlation with the lymphoedema's importance. Lymphoscintigraphy with sup(99m)Tc antimony sulfide colloid is a simple examination but some side effects may occur. In 7 patients, post-injection lymphangitis was observed, with favorable evolution under antibiotic treatment. The lymphoscintigraphy can give some interesting information on the evolution of treated lymphoedema

  8. Co-administration of glycyrrhizic acid with the antileishmanial drug sodium antimony gluconate (SAG) cures SAG-resistant visceral leishmaniasis.

    Science.gov (United States)

    Bhattacharjee, Amrita; Majumder, Saikat; Majumdar, Suchandra Bhattacharyya; Choudhuri, Soumitra Kumar; Roy, Syamal; Majumdar, Subrata

    2015-03-01

    Since there are very few affordable antileishmanial drugs available, antimonial resistance has crippled antileishmanial therapy, thereby emphasising the need for development of novel therapeutic strategies. This study aimed to evaluate the antileishmanial role of combined therapy with sodium antimony gluconate (SAG) and the triterpenoid glycyrrhizic acid (GA) against infection with SAG-resistant Leishmania (GE1F8R). Combination therapy with GA and SAG successfully limited infection with SAG-resistant Leishmania in a synergistic manner (fractional inhibitory concentration index resistant Leishmania and co-treated with GA and SAG exhibited a significant reduction in hepatic and splenic parasite burden. In probing the mechanism, it was observed that GA treatment suppressed the expression and efflux activity of P-glycoprotein (P-gp) and multidrug resistance-associated protein 1 (MRP1), two host ABC transporters responsible for antimony efflux from host cells infected with SAG-resistant parasites. This suppression correlated with greater intracellular antimony retention during SAG therapy both in vitro and in vivo, which was reflected in the reduced parasite load. Furthermore, co-administration of GA and SAG induced a shift in the cytokine balance towards a Th1 phenotype by augmenting pro-inflammatory cytokines (such as IL-12, IFNγ and TNFα) and inducing nitric oxide generation in GE1F8R-infected macrophages as well as GE1F8R-infected mice. This study aims to provide an affordable leishmanicidal alternative to expensive antileishmanial drugs such as miltefosine and amphotericin B. Furthermore, this report explores the role of GA as a resistance modulator in MRP1- and P-gp-overexpressing conditions. PMID:25600891

  9. Exploring screen printing technology on thermoelectric energy harvesting with printing copper-nickel and bismuth-antimony thermocouples

    OpenAIRE

    Cao, Zhuo; Koukharenko, Elena; Torah, R; Beeby, SP

    2013-01-01

    This paper reports the fabrication and testing of copper (Cu) - nickel (Ni) and bismuth (Bi) - antimony (Sb) based thermocouples fabricated using screen printing technology. The transport properties of the printed thermoelectric material were measured in room temperature while the Seebeck voltage and power output of the printed thermocouples were tested under a variety temperature gradient. Initial thermoelectric materials have been integrated in inks and then deposited on substrate by the si...

  10. The Potential Impact of Biofield Energy Treatment on the Atomic and Physical Properties of Antimony Tin Oxide Nanopowder

    OpenAIRE

    Trivedi, Mahendra Kumar

    2015-01-01

    Antimony tin oxide (ATO) is known for its high thermal conductivity, optical transmittance, and wide energy band gap, which makes it a promising material for the display devices, solar cells, and chemical sensor industries. The present study was undertaken to evaluate the effect of biofield energy treatment on the atomic and physical properties of ATO nanopowder. The ATO nanopowder was divided into two parts: control and treated. The treated part was subjected to Mr. Trivedi’s biofield ...

  11. The influence of remelting on the properties of AlSi6Cu4 alloy modified by antimony

    OpenAIRE

    D. Medlen; D. Bolibruchova

    2012-01-01

    The paper deals with the problem of multiple remelting influence on AlSi6Cu4 alloy modified by antimony on chosen mechanical characteristics, microstructure and gas content. This foundry alloy is used mostly in automotive industry. Foundry Aluminum-Silicon alloys are also used in number of industrial weight sensitive applications because of their low weight and very good castability and good mechanical properties. Modifiers are usually added to molten aluminum-silicon alloys to refine the eut...

  12. EFFECT OF GRAIN BOUNDARY SEGREGATION OF ANTIMONY ON RELAXATION AT GRAIN BOUNDARIES IN SILICON-IRON ALLOYS

    OpenAIRE

    Iwasaki, Y.; Fujimoto, K

    1981-01-01

    A sharp grain boundary peak appears in both 2 and 3% silicon-iron alloys due to a substitutional solute of silicon. This peak is highly sensitive to the segregation of the third element of antimony and, contrary to orthodox solute peaks in binary and ternary alloys, largely decreases in magnitude on heating after a segregation treatment. The subsequent measurement on cooling returns the peak to the ordinary magnitude. As a function of annealing time at a temperature of segregation, the height...

  13. 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.

  14. Precipitation of antimony from the solution of sodium thioantimonite by air oxidation in the presence of catalytic agents

    Institute of Scientific and Technical Information of China (English)

    杨天足; 赖琼琳; 唐建军; 楚广

    2002-01-01

    The behavior of antimony oxidation in the solution of sodium thioantimonite was studied in the presence of catalytic agents. The catalytic effects of the respective addition of cupric sulfate, sodium tartrate, potassium permanganate, phenol, 1,2-dihydroxybenzene and their combination on the oxidation of sodium thioantimonite were investigated. A pilot test was carried out. The results show that the respective use of sodium tartrate, cupric sulfate, potassium permanganate, phenol and 1,2-dihydroxybenzene have little catalytic effect on the oxidation of sodium thioantimonite. However there exists obvious catalytic oxidation by the combination of 0.25 g/L 1,2-dihydroxybenzene, 0.5 g/L potassium permanganate and 1.0 g/L phenol. Moreover, high blast intensity, the increase of temperature and NaOH concentration favor the oxidation of antimony. The oxidation process of antimony has such advantages as quick reaction and low operation costs. The results of the pilot test are consistent with those of laboratory experiments.

  15. Separation of Lead from Crude Antimony by Pyro-Refining Process with NaPO3 Addition

    Science.gov (United States)

    Ye, Longgang; Hu, Yuejie; Xia, Zhimei; Chen, Yongming

    2016-06-01

    The main purpose of this study was to separate lead from crude antimony through an oxidation pyro-refining process and by using sodium metaphosphate as a lead elimination reagent. The process parameters that will affect the refining results were optimized experimentally under controlled conditions, such as the sodium metaphosphate charging dosage, the refining temperature and duration, and the air flow rate, to determine their effect on the lead content in refined antimony and the lead removal rate. A minimum lead content of 0.0522 wt.% and a 98.6% lead removal rate were obtained under the following optimal conditions: W_{{{NaPO}_{{3}} }} = 15% W Sb (where W represents weight), a refining temperature of 800°C, a refining time of 30 min, and an air flow rate of 3 L/min. X-ray diffractometry and scanning electron microscopy showed that high-purity antimony was obtained. The smelting operation is free from smoke or ammonia pollution when using monobasic sodium phosphate or ammonium dihydrogen phosphate as the lead elimination reagent. However, this refining process can also remove a certain amount of sulfur, cobalt, and silicon simultaneously, and smelting results also suggest that sodium metaphosphate can be used as a potential lead elimination reagent for bismuth and copper refining.

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

    Science.gov (United States)

    LYRA, Marcelo Rosandiski; PASSOS, Sonia Regina Lambert; PIMENTEL, Maria Inês Fernandes; BEDOYA-PACHECO, Sandro Javier; VALETE-ROSALINO, Cláudia Maria; VASCONCELLOS, Erica Camargo Ferreira; ANTONIO, Liliane Fatima; SAHEKI, Mauricio Naoto; SALGUEIRO, Mariza Mattos; SANTOS, Ginelza Peres Lima; RIBEIRO, Madelon Noato; CONCEIÇÃO-SILVA, Fatima; MADEIRA, Maria Fatima; SILVA, Jorge Luiz Nunes; FAGUNDES, Aline; SCHUBACH, Armando Oliveria

    2016-01-01

    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. PMID:27680173

  17. Exploring the electronic structure and optical properties of the quaternary selenide compound, Ba4Ga4SnSe12: For photovoltaic applications

    International Nuclear Information System (INIS)

    Due to huge demand on discovering new materials for energy, we used first-principle calculations to explore the electronic structure and optical properties of a recent quaternary selenide, namely Ba4Ga4SnSe12. The electronic structure and the optical properties of Ba4Ga4SnSe12 were calculated through a reliable approach of Engle Vosko-GGA (EV-GGA). We found that Ba4Ga4SnSe12 has a direct band gap of 2.14 eV positioned at Γ. Acquiring the fundamental characteristics of Ba4Ga4SnSe12, we studied the linear optical properties like dielectric function in the energy range of 0–14 eV. From the dielectric function we noticed a weak directional anisotropy for the two components. The absorption spectrum indicates the possibility of greater multiple direct and indirect inter-band transitions in the visible regions and shows similar behavior with experimental spectrum. Ba4Ga4SnSe12 can be used as shielding material from UV radiations. Present study predicts that the Ba4Ga4SnSe12 is promising for photovoltaic applications due to their high absorption of solar radiations and photoconductivity in the visible range. - Graphical abstract: Interesting quaternary selenide compound, Ba4Ga4SnSe12, for photovoltaic applications. - Highlights: • Ba4Ga4SnSe12 is a quaternary selenide designed for PV and thermoelectric. • Ba4Ga4SnSe12 has a direct band gap of 2.14 eV. • Ba4Ga4SnSe12, has a maximum reflectivity in the visible and UV regions

  18. Thin film metallic glass as a diffusion barrier for copper indium gallium selenide solar cell on stainless steel substrate: A feasibility study

    Science.gov (United States)

    Diyatmika, Wahyu; Xue, Lingjun; Lin, Tai-Nan; Chang, Chia-wen; Chu, Jinn P.

    2016-08-01

    The feasibility of using Zr53.5Cu29.1Al6.5Ni10.9 thin-film metallic glass (TFMG) as a diffusion barrier for copper indium gallium selenide (CIGS) solar cells on stainless steel (SS) is investigated. The detrimental Fe diffusion from SS into CIGS is found to be effectively hindered by the introduction of a 70-nm-thick TFMG barrier; the cell performance is thus improved. Compared with the 2.73% of CIGS on bare SS, a higher efficiency of 5.25% is obtained for the cell with the Zr52Cu32Al9Ni7 TFMG barrier.

  19. Study of the crystallographic phase change on copper (I) selenide thin films prepared through chemical bath deposition by varying the pH of the solution

    Science.gov (United States)

    Sandoval-Paz, M. G.; Rodríguez, C. A.; Porcile-Saavedra, P. F.; Trejo-Cruz, C.

    2016-07-01

    Copper (I) selenide thin films with orthorhombic and cubic structure were deposited on glass substrates by using the chemical bath deposition technique. The effects of the solution pH on the films growth and subsequently the structural, optical and electrical properties of the films were studied. Films with orthorhombic structure were obtained from baths wherein both metal complex and hydroxide coexist; while films with cubic structure were obtained from baths where the metal hydroxide there is no present. The structural modifications are accompanied by changes in bandgap energy, morphology and electrical resistivity of the films.

  20. The stability domain of the selenide kesterite photovoltaic materials and NMR investigation of the Cu/Zn disorder in Cu2ZnSnSe4 (CZTSe).

    Science.gov (United States)

    Choubrac, Léo; Lafond, Alain; Paris, Michaël; Guillot-Deudon, Catherine; Jobic, Stéphane

    2015-06-21

    Bulk compounds, prepared via the ceramic route, related to Cu2ZnSnSe4 (CZTSe), a material considered for use in photovoltaic devices, were investigated using NMR spectroscopy, electron-probe microanalyses and X-ray diffraction. These materials adopt the kesterite structure regardless of the Cu and Zn contents. It is also shown that the stability domain of the copper-poor quaternary phases is wider for selenide derivatives than for sulphides. Finally, the Cu/Zn disorder level in CZTSe is found to be higher when the samples are quenched, which is reminiscent of the behaviour of the parent sulphide compounds CZTS. PMID:25990030

  1. Polyamide–thallium selenide composite materials via temperature and pH controlled adsorption–diffusion method

    Energy Technology Data Exchange (ETDEWEB)

    Ivanauskas, Remigijus; Samardokas, Linas [Department of Physical and Inorganic Chemistry, Kaunas University of Technology, Radvilenu str. 19, Kaunas LT-50254 (Lithuania); Mikolajunas, Marius; Virzonis, Darius [Department of Technology, Kaunas University of Technology, Panevezys Faculty, Daukanto 12, 35212 Panevezys (Lithuania); Baltrusaitis, Jonas, E-mail: job314@lehigh.edu [Department of Chemical and Biomolecular Engineering, Lehigh University, B336 Iacocca Hall, 111 Research Drive, Bethlehem, PA 18015 (United States)

    2014-10-30

    Graphical abstract: Single phase polyamide–thallium selenide hybrid functional materials were synthesized for solar energy conversion. - Highlights: • Thallium selenide–polyamide composite materials surfaces synthesized. • Mixed phase composition confirmed by XRD. • Increased temperature resulted in a denser surface packing. • Urbach energies correlated with AFM showing decreased structural disorder. • Annealing in N{sub 2} at 100 °C yielded a single TlSe phase. - Abstract: Composite materials based on III–VI elements are promising in designing efficient photoelectronic devices, such as thin film organic–inorganic solar cells. In this work, TlSe composite materials were synthesized on a model polymer polyamide using temperature and pH controlled adsorption–diffusion method via (a) selenization followed by (b) the exposure to the group III metal (Tl) salt solution and their surface morphological, chemical and crystalline phase information was determined with particular focus on their corresponding structure–optical property relationship. XRD analysis yielded a complex crystalline phase distribution which correlated well with the optical and surface morphological properties measured. pH 11.3 and 80 °C yielded well defined, low structural disorder composite material surface. After annealing in N{sub 2} at 100 °C, polycrystalline PA-Tl{sub x}Se{sub y} composite materials yielded a single TlSe phase due to the enhanced diffusion and reaction of thallium ions into the polymer. The method described here can be used to synthesize variety of binary III–VI compounds diffused into the polymer at relatively low temperatures and low overall cost, thus providing for a flexible synthesis route for novel composite solar energy harvesting materials.

  2. A study on low cost-high conducting fluorine and antimony-doped tin oxide thin films

    International Nuclear Information System (INIS)

    Thin films of undoped, fluorine- and antimony-doped tin oxide on glass at 400 deg. C was prepared by spray pyrolysis technique. Tin chloride (SnCl2), ammonium fluoride (NH4F), and antimony trichloride (SbCl3) were used as source for tin (Sn), fluorine (F), and antimony (Sb), respectively. To ensure the control of solution concentration on growth rate, fluorine-doped tin oxide (SnO2:F) thin films were first prepared with different amount of tin precursor, in the range of 5-12g, which has resulted in deposition of films with different thickness values. The optimum amount of tin precursor found from this study (11g) was fixed constant for preparing SnO2 films with different doping levels of F and Sb. From the X-ray diffraction analyses, it is understood that the preferred orientation of SnO2:F films is dependent on their thickness and the solution concentration. The variation in the solution concentration and orientation of the films was reflected in their morphology as examined by scanning electron microscopy (SEM) and atomic force microscopy (AFM). SEM studies showed that the variation in the solution concentration lead to different grain shapes for different orientations. The AFM study showed that the RMS roughness of undoped films reduced considerably from 86 to 24nm due to fluorine doping (15wt.%), whereas the antimony doping (2wt.%) has no significance effect on RMS roughness (93nm). The electrical properties of the films were examined by a Hall measurements setup in van der Pauw configuration. A minimum sheet resistance of 1.75 and 2.17Ω/ were obtained for F and Sb doped films, respectively. From the optical studies, it is found that the transmittance of undoped films increased from 42% to a maximum 85% on 30wt.% fluorine doping, whereas that has been decreased to a minimum of 12% on 4wt.% antimony doping (800nm). A discussion on the effect of type of dopants and their concentration on the structural, electrical and optical properties of the SnO2 film have

  3. Preparation of antimony sulfide semiconductor nanoparticles by pulsed laser ablation in liquid

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Ren-De, E-mail: son003@sekisui.com [Research & Development Institute, High Performance Plastics Company, Sekisui Chemical Co., Ltd. 2-1 Hyakuyama, Shimamoto-Cho, Mishima-Gun, Osaka, 618-0021 (Japan); Tsuji, Takeshi [Interdisciplinary Graduate School of Science and Engineering, Shimane University, 1060 Nishikawatsu-Cho, Matsue, 690-8504 (Japan)

    2015-09-01

    Highlights: • Pulsed laser ablation in liquid (LAL) was applied to prepare antimony sulfide nanoparticles (Sb{sub 2}S{sub 3} NPs). • Sb{sub 2}S{sub 3} NPs with a stoichiometric composition were successfully prepared by LAL in water without using any surfactants or capping agents. • Thus-prepared Sb{sub 2}S{sub 3} NPs showed low-temperature crystallization and melting at a temperature low as 200 °C. • The NPs-coated Sb{sub 2}S{sub 3} thin film showed comparable semiconductor properties (carrier mobility and carrier density) to the vacuum deposited one. • Byproducts such as CS{sub 2}, CH{sub 4} and CO were detected by GC-MS analysis when LAL was performed in organic solvent. • The LAL-induced decomposition mechanism of Sb{sub 2}S{sub 3} and organic solvents was discussed based on the GC-MS results. - Abstract: In this paper, we report on the synthesis of antimony sulfide (Sb{sub 2}S{sub 3}) semiconductor nanoparticles by pulsed laser ablation in liquid without using any surfactants or capping agents. Different results were obtained in water and organic solvents. In the case of water, Sb{sub 2}S{sub 3} nanoparticles with chemical compositions of stoichiometry were successfully prepared when laser irradiation was performed under the condition with the dissolved oxygen removed by argon gas bubbling. It was shown that thus-obtained Sb{sub 2}S{sub 3} nanoparticles exhibit features of not only low-temperature crystallization but also low-temperature melting at a temperature as low as 200 °C. Nanoparticle-coated Sb{sub 2}S{sub 3} thin films were found to show good visible light absorption and satisfying semiconductor properties (i.e., carrier mobility and density), which are essential for photovoltaic application. On the other hand, in the case of organic solvents (e.g., acetone, ethanol), such unexpected byproducts as CS{sub 2}, CO and CH{sub 4} were detected from the reaction system by GC-MS analysis, which suggests that both Sb{sub 2}S{sub 3} and organic

  4. Infrared-to-red upconversion luminescence in samarium-doped antimony glasses

    Energy Technology Data Exchange (ETDEWEB)

    Som, Tirtha [Glass Technology Laboratory, Glass Division, Central Glass and Ceramic Research Institute, 196 Raja S.C. Mullick Road, Kolkata 700 032 (India); Karmakar, Basudeb [Glass Technology Laboratory, Glass Division, Central Glass and Ceramic Research Institute, 196 Raja S.C. Mullick Road, Kolkata 700 032 (India)], E-mail: basudebk@cgcri.res.in

    2008-12-15

    A new antimony-based glass system (K{sub 2}O-B{sub 2}O{sub 3}-Sb{sub 2}O{sub 3}) having low phonon energy (about 600 cm{sup -1}) doped with Sm{sup 3+} ions has been developed. Infrared reflection spectroscopic (IRRS) studies have been employed to establish its low phonon energy. Ultraviolet-Visible-near infrared (UV-Vis-NIR) absorption and photoluminescence upconversion properties with the spectrochemistry of the 15K{sub 2}O-15B{sub 2}O{sub 3}-70Sb{sub 2}O{sub 3} (mol%) glasses have been studied doping with different concentrations (0.1-1.0 wt%) of Sm{sub 2}O{sub 3}. UV-Vis-NIR absorption band positions have been justified with quantitative calculation of nephelauxetic parameter and covalent bonding characteristics of the host. NIR to visible upconversion has been investigated by exciting at 949 nm at room temperature. Three upconverted bands originating from the {sup 4}G{sub 5/2}{yields}{sup 6}H{sub 5/2}, {sup 4}G{sub 5/2}{yields}{sup 6}H{sub 7/2} and {sup 4}G{sub 5/2}{yields}{sup 6}H{sub 9/2} transitions are found to be centered at 566 (green, weak), 602 (orange, weak) and 636 (red, remarkably strong) nm, respectively. These bands have been explained from the evaluation of the absorption, normal (downconversion) fluorescence and excitation spectra. The upconversion processes have been explained by the excited state absorption (ESA), energy transfer (ET) and cross-relaxation (CR) mechanisms involving population of the metastable (storage) energy level ({sup 4}G{sub 5/2}) by multiphonon deexcitation effect. It is evident from the IRRS study that the upconversion phenomena are expedited by the low multiphonon relaxation rate in antimony glasses owing to their low phonon energy (602 cm{sup -1}, the main and highest intensity Sb-O-Sb stretching band) which is very close to that of fluoride glasses (500-600 cm{sup -1})

  5. Inhibition of Leishmania donovani promastigote DNA topoisomerase I and human monocyte DNA topoisomerases I and II by antimonial drugs and classical antitopoisomerase agents.

    Science.gov (United States)

    Walker, John; Saravia, Nancy G

    2004-10-01

    We have compared the inhibitor sensitivities of DNA topoisomerase I (TOPI) from Leishmania donovani promastigotes and TOPs I and II of human monocytes using pentavalent and trivalent antimonials (SbV, SbIII) and classical TOP inhibitors. Bis-benzimidazoles (Hoechst-33258 and -33342) were potent inhibitors of both parasite and human TOPI, but Hoechst-33342 was markedly less cytotoxic to promastigotes than to monocytes in vitro. Leishmania donovani was also considerably less sensitive than monocytes to camptothecin, both at enzyme and cellular levels. Sodium stibogluconate (SSG) was the only antimonial to inhibit TOPI, exhibiting a significant (P donovani enzyme but showed low cytotoxicities against intact promastigotes. The SbV meglumine antimoniate failed to inhibit TOPI and showed negligible cytotoxicities, whereas SbIII drugs were lethal to parasites and monocytes yet poor inhibitors of TOPI. Monocyte TOPII was inhibited by bis-benzimidazoles and insensitive to antimonials and camptothecin. The disparity between the high leishmanicidal activity and low anti-TOPI potency of SbIII indicates that in vivo targeting of L. donovani TOPI by the reductive pathway of antimonial activation is improbable. Nevertheless, the potent direct inhibition of TOPI by SSG and the differential interactions of camptothecin with L. donovani and human TOPI support the possibility of developing parasite-specific derivatives. PMID:15562618

  6. Chronic exposure to arsenic in drinking water can lead to resistance to antimonial drugs in a mouse model of visceral leishmaniasis

    Science.gov (United States)

    Perry, Meghan R.; Wyllie, Susan; Raab, Andrea; Feldmann, Joerg; Fairlamb, Alan H.

    2013-01-01

    The Indian subcontinent is the only region where arsenic contamination of drinking water coexists with widespread resistance to antimonial drugs that are used to treat the parasitic disease visceral leishmaniasis. We have previously proposed that selection for parasite resistance within visceral leishmaniasis patients who have been exposed to trivalent arsenic results in cross-resistance to the related metalloid antimony, present in the pentavalent state as a complex in drugs such as sodium stibogluconate (Pentostam) and meglumine antimonate (Glucantime). To test this hypothesis, Leishmania donovani was serially passaged in mice exposed to arsenic in drinking water at environmentally relevant levels (10 or 100 ppm). Arsenic accumulation in organs and other tissues was proportional to the level of exposure and similar to that previously reported in human liver biopsies. After five monthly passages in mice exposed to arsenic, isolated parasites were found to be completely refractory to 500 μg⋅mL−1 Pentostam compared with the control passage group (38.5 μg⋅mL−1) cultured in vitro in mouse peritoneal macrophages. Reassessment of resistant parasites following further passage for 4 mo in mice without arsenic exposure showed that resistance was stable. Treatment of infected mice with Pentostam confirmed that resistance observed in vitro also occurred in vivo. We conclude that arsenic contamination may have played a significant role in the development of Leishmania antimonial resistance in Bihar because inadequate treatment with antimonial drugs is not exclusive to India, whereas widespread antimonial resistance is. PMID:24167266

  7. Chronic exposure to arsenic in drinking water can lead to resistance to antimonial drugs in a mouse model of visceral leishmaniasis.

    Science.gov (United States)

    Perry, Meghan R; Wyllie, Susan; Raab, Andrea; Feldmann, Joerg; Fairlamb, Alan H

    2013-12-01

    The Indian subcontinent is the only region where arsenic contamination of drinking water coexists with widespread resistance to antimonial drugs that are used to treat the parasitic disease visceral leishmaniasis. We have previously proposed that selection for parasite resistance within visceral leishmaniasis patients who have been exposed to trivalent arsenic results in cross-resistance to the related metalloid antimony, present in the pentavalent state as a complex in drugs such as sodium stibogluconate (Pentostam) and meglumine antimonate (Glucantime). To test this hypothesis, Leishmania donovani was serially passaged in mice exposed to arsenic in drinking water at environmentally relevant levels (10 or 100 ppm). Arsenic accumulation in organs and other tissues was proportional to the level of exposure and similar to that previously reported in human liver biopsies. After five monthly passages in mice exposed to arsenic, isolated parasites were found to be completely refractory to 500 μg · mL(-1) Pentostam compared with the control passage group (38.5 μg · mL(-1)) cultured in vitro in mouse peritoneal macrophages. Reassessment of resistant parasites following further passage for 4 mo in mice without arsenic exposure showed that resistance was stable. Treatment of infected mice with Pentostam confirmed that resistance observed in vitro also occurred in vivo. We conclude that arsenic contamination may have played a significant role in the development of Leishmania antimonial resistance in Bihar because inadequate treatment with antimonial drugs is not exclusive to India, whereas widespread antimonial resistance is.

  8. 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.

  9. 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. PMID:26237216

  10. Direct Band Gap Gallium Antimony Phosphide (GaSbxP(1-x)) Alloys.

    Science.gov (United States)

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

    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 GaSbxP(1-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 GaSbxP(1-x). Furthermore, these calculations indicate band edge straddling of the hydrogen evolution and oxygen evolution reactions for compositions ranging from x = 0.0092 Sb up to at least x = 0.065 Sb making it a candidate for use in a Schottky type photoelectrochemical water splitting device. GaSbxP(1-x) nanowires were synthesized by reactive transport utilizing a microwave plasma discharge with average compositions ranging from x = 0.06 to x = 0.12 Sb and direct band gaps between 2.21 eV and 1.33 eV. Photoelectrochemical experiments show that the material is photoactive with p-type conductivity. This study brings attention to a relatively uninvestigated, tunable band gap semiconductor system with tremendous potential in many fields. PMID:26860470

  11. Direct Band Gap Gallium Antimony Phosphide (GaSbxP1-x) Alloys

    Science.gov (United States)

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

    2016-02-01

    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 hydrogen evolution and oxygen evolution reactions for compositions ranging from x = 0.0092 Sb up to at least x = 0.065 Sb making it a candidate for use in a Schottky type photoelectrochemical water splitting device. GaSbxP1-x nanowires were synthesized by reactive transport utilizing a microwave plasma discharge with average compositions ranging from x = 0.06 to x = 0.12 Sb and direct band gaps between 2.21 eV and 1.33 eV. Photoelectrochemical experiments show that the material is photoactive with p-type conductivity. This study brings attention to a relatively uninvestigated, tunable band gap semiconductor system with tremendous potential in many fields.

  12. Adsorption behavior of antimony(III) oxyanions on magnetite surface in aqueous organic acid environment

    Science.gov (United States)

    Mittal, Vinit K.; Bera, Santanu; Narasimhan, S. V.; Velmurugan, S.

    2013-02-01

    Antimony(III) adsorption is observed on magnetite (Fe3O4) surface under acidic and reducing condition through surface hydroxyl (SOH) groups bonding on Fe3O4 surface. Desorption of adsorbed Sb(III) is observed from Fe3O4 surface along with iron release in organic acid at 85 °C after 5 h of experiment. Tartaric acid (TA) shows minimum Sb(III) adsorption on Fe3O4 among the organic acid studied. The reason is TA having two sets of adjacent functional groups viz. Odbnd Csbnd OH and Csbnd OH which are responsible for the formation of five-membered bidendate chelate with Sb(III). Other oxyanions, cations or complexing agents along with TA influences the Sb(III) adsorption on Fe3O4. The surface of magnetite is modified by the addition of fatty acids viz. Lauric acid, benzoic acid to bind the Ssbnd OH groups present on the surface. This results in delaying the process of adsorption without changing the quantity of saturation adsorption of Sb(III) on Fe3O4 surface.

  13. Large anharmonic effect and thermal expansion anisotropy of metal chalcogenides: The case of antimony sulfide

    Science.gov (United States)

    Gan, Chee Kwan; Soh, Jian Rui; Liu, Yun

    2015-12-01

    We derive a compact matrix expression for the linear thermal expansion coefficients (TECs) for a general orthorhombic system which relates elastic properties and integrated quantities based on deformation and mode dependent Grüneisen parameters and mode dependent heat capacities. The density of Grüneisen parameters Γ (ν ) as a function of frequency ν , weighted by the number of phonon modes, is introduced and found to be illuminating in interpreting the TEC results. Using density functional perturbation theory and Grüneisen formalism for thermal expansion, we illustrate the general usefulness of this method by calculating the linear and volumetric TECs of a low-symmetry orthorhombic compound antimony sulfide (Sb2S3 ), which belongs to a large class of technologically and fundamentally important materials. Even though negative Grüneisen parameters are found for deformations in all three crystal directions, the Γ (ν ) data rule out the occurrences of negative TECs at all temperatures. Sb2S3 exhibits a large thermal expansion anisotropy where the TEC in the b direction can reach as high as 13 ×10-6 K-1 at high temperatures, about two and seven times larger than the TECs in the c and a direction, respectively. Our work suggests a general and practical first-principles approach to calculate the thermal properties of other complicated low-symmetry systems.

  14. Controlled n-doping in chemical vapour deposition grown graphene by antimony

    International Nuclear Information System (INIS)

    We have studied the effects of antimony (Sb) doping on graphene grown by chemical vapour deposition without any significant change in its electrical properties. By increasing the metal thickness from 1 to 5 nm, we found a shift in the wave numbers of Raman G and two-dimensional (2D) peaks consistent with n-doping and a change in the Fermi level of the graphene into the conduction band. The relative intensity of the D peak to the G peak did not show a significant change and that of the 2D peak to the G peak remained at a large enough number as a function of metal thickness, implying little degradation by the metal dopants. Transport measurements also confirm the n-doping of graphene through a shift of Dirac point in the transfer characteristics and the quality preservation with little changes in mobility. We also report on the formation of a p–n junction by metal doping on selected areas of the graphene and their electrical properties with transfer characteristics and Hall measurements. (paper)

  15. Evaluation of atmospheric inputs as possible sources of antimony in pregnant women from urban areas.

    Science.gov (United States)

    Fort, Marta; Grimalt, Joan O; Querol, Xavier; Casas, Maribel; Sunyer, Jordi

    2016-02-15

    Antimony and copper are common components of brake linings. The occurrence of these two metals in urban atmospheric aerosols has been related to vehicular use. Urine samples (n=466) taken during the 32nd week of pregnancy were analyzed for Sb and Cu in pregnant women from an urban area (Sabadell, Catalonia, Spain). The geometric mean levels were 0.28 and 13 μg/g creatinine, respectively. Positive significant associations between urine concentrations of Sb and seasonality, intensity of physical exercise, working activities and traffic intensity at their home streets were observed. Cu showed the same trends but without statistical significance. In both cases, the estimated dietary ingestion of these two metals was larger than the inhalation inputs but the difference was much higher for Cu than for Sb. While Sb has no dietary role, Cu is an essential element which is also incorporated into humans through diet. The results suggest that inhalation of atmospheric particles may also constitute a source of Sb in pregnant women and general population of urban areas. PMID:26657384

  16. 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.

  17. Spark Plasma Sintering and Densification Mechanisms of Antimony-Doped Tin Oxide Nanoceramics

    Directory of Open Access Journals (Sweden)

    Junyan Wu

    2013-01-01

    Full Text Available Densification of antimony-doped tin oxide (ATO ceramics without sintering aids is very difficult, due to the volatilization of SnO2, formation of deleterious phases above 1000°C, and poor sintering ability of ATO particles. In this paper, monodispersed ATO nanoparticles were synthesized via sol-gel method, and then ATO nanoceramics with high density were prepared by spark plasma sintering (SPS technology using the as-synthesized ATO nanoparticles without the addition of sintering aids. The effect of Sb doping content on the densification was investigated, and the densification mechanisms were explored. The results suggest that ATO nanoparticles derived from sol-gel method show good crystallinity with a crystal size of 5–20 nm and Sb is incorporated into the SnO2 crystal structure. When the SPS sintering temperature is 1000°C and the Sb doping content is 5 at.%, the density of ATO nanoceramics reaches a maximum value of 99.2%. Densification mechanisms are explored in detail.

  18. A new method for antimony speciation in plant biomass and nutrient media using anion exchange cartridge.

    Science.gov (United States)

    Tisarum, Rujira; Ren, Jing-Hua; Dong, Xiaoling; Chen, Hao; Lessl, Jason T; Ma, Lena Q

    2015-11-01

    A selective separation method based on anion exchange cartridge was developed to determine antimony (Sb) speciation in biological matrices by graphite furnace atomic absorption spectrophotometry (GFAAS). The selectivity of the cartridge towards antimonite [Sb(III)] and antimonate [Sb(V)] reversed in the presence of deionized (DI) water and 2mM citric acid. While Sb(V) was retained by the cartridge in DI water, Sb(III) was retained in citric acid media. At pH 6, Sb(III) and Sb(V) formed Sb(III)- and Sb(V)-citrate complexes, but the cartridge had higher affinity towards the Sb(III)-citrate complex. Separation of Sb(III) was tested at various concentrations in fresh and spent growth media and plant tissues. Our results showed that cartridge-based Sb speciation was successful in plant tissues, which was confirmed by HPLC-ICP-MS. The cartridge retained Sb(III) and showed 92-104% Sb(V) recovery from arsenic hyperaccumulator Pteris vittata roots treated with Sb(III) and Sb(V). The cartridge procedure is an effective alternative for Sb speciation, offering low cost, reproducible results, and simple Sb analysis using GFAAS.

  19. Antimony release from contaminated mine soils and its migration in four typical soils using lysimeter experiments.

    Science.gov (United States)

    Shangguan, Yu-Xian; Zhao, Long; Qin, Yusheng; Hou, Hong; Zhang, Naiming

    2016-11-01

    Antimony (Sb) can pose great risks to the environment in mining and smelting areas. The migration of Sb in contaminated mine soil was studied using lysimeter experiments. The exchangeable concentration of soil Sb decreased with artificial leaching. The concentrations of Sb retained in the subsoil layers (5-25cm deep) were the highest for Isohumosol and Ferrosol and the lowest for Sandy soil. The Sb concentrations in soil solutions decreased with soil depth, and were adequately simulated using a logarithmic function. The Sb migration pattern in Sandy soil was markedly different from the patterns in the other soils which suggested that Sb may be transported in soil colloids. Environmental factors such as water content, soil temperature, and oxidation-reduction potential of the soil had different effects on Sb migration in Sandy soil and Primosol. The high Fe and Mn contents in Ferrosol and Isohumosol significantly decreased the mobility of Sb in these soils. The Na and Sb concentrations in soils used in the experiments positively correlated with each other (Psoil solutions, the Sb chemical fraction patterns, and the Sb/Na ratios decreased in the order Sandy soil>Primosol>Isohumosol>Ferrosol, and we concluded that the Sb mobility in the soils also decreased in that order. PMID:27395817

  20. 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.

  1. Semiconductor nanocrystals functionalized with antimony telluride zintl ions for nanostructured thermoelectrics.

    Science.gov (United States)

    Kovalenko, Maksym V; Spokoyny, Boris; Lee, Jong-Soo; Scheele, Marcus; Weber, Andrew; Perera, Susanthri; Landry, Daniel; Talapin, Dmitri V

    2010-05-19

    The energy efficiency of heat engines could be improved by the partial recovery of waste heat using thermoelectric (TE) generators. We show the possibility of designing nanostructured TE materials using colloidal inorganic nanocrystals functionalized with molecular antimony telluride complexes belonging to the family of Zintl ions. The unique advantage of using Zintl ions as the nanocrystal surface ligands is the possibility to convert them into crystalline metal chalcogenides, thus linking individual nanobuilding blocks into a macroscopic assembly of electronically coupled functional modules. This approach allows preserving the benefits of nanostructuring and quantum confinement while enabling facile charge transport through the interparticle boundaries. A developed methodology was applied for solution-based fabrication of nanostructured n- and p-type Bi(2-x)Sb(x)Te(3) alloys with tunable composition and PbTe-Sb(2)Te(3) nanocomposites with controlled grain size. Characterization of the TE properties of these materials showed that their Seebeck coefficients, electrical and thermal conductivities, and ZT values compared favorably with those of previously reported solution-processed TE materials.

  2. 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.

  3. Comparison of arsenic and antimony biogeochemical behavior in water, soil and tailings from Xikuangshan, China.

    Science.gov (United States)

    Fu, Zhiyou; Wu, Fengchang; Mo, Changli; Deng, Qiujing; Meng, Wei; Giesy, John P

    2016-01-01

    Although similar geochemical behaviors of arsenic (As) and antimony (Sb) in the environment has been assumed and widely reported, growing evidence suggests the two elements cannot, under some conditions, be assumed to behave similarly. In this four-year study (samples collected in each year), comparative investigation of the biogeochemistry of As and Sb in water/fish, soil/vegetable, tailings/plant samples were carried out at the world's largest active Sb mine area (Xikuangshan, China). Depending on duration the tailings had been stacked, significant differences in spatial distributions between As and Sb were found, and these were associated with change in pH over time. Bio-accumulation factors (BAFs) of As were approximately 10-fold greater than those of Sb in fish/water, plant/tailing, and vegetable/soil systems. Sb had higher BAF in non-fatty tissues such as gills of fishes and shells of crabs. BAFs of Sb in vegetable/soil exhibited insignificantly, but different from As, positive correlation with pH in soil. PMID:26356182

  4. Validation of methodology and uncertainty assessment of antimony determination in environmental materials using Neutron Activation Analysis

    International Nuclear Information System (INIS)

    Antimony is an element found in low concentrations in the environment. However, its determination has attracted great interest because of the knowledge of its toxicity and increasing application. Neutron activation analysis (NAA) is a suitable method for the determination of several elements in different types, but in case of Sb, the analysis presents some difficulties due to spectral interferences. The objective of this research was to validate the method of NAA and uncertainty assessment for Sb determination in environmental samples. The experimental procedure consisted of irradiating twelve certified reference samples of different kind of matrices. The samples were irradiated in the nuclear research reactor IEA R1 IPEN/CNEN/SP followed by measurement of induced radioactivity, using a hyperpure germanium detector coupled to a gamma ray spectrometry. The radioisotopes 122Sb and 124Sb were measured and the Sb concentrations with their respective uncertainties were obtained by the comparative method. Relative errors and values of Z scores were calculated to evaluate the accuracy of the results for Sb determination in certified reference materials. The evaluation of the components that contribute to uncertainty measurement of the Sb concentration, showed that the major uncertainty contribution is due to statistical counting. The results also indicated that the uncertainty value of the combined standard uncertainty depends on the radioisotope measured and the decay time used for counting. (author)

  5. Antimony-Doped Tin Oxide Thin Films Grown by Home Made Spray Pyrolysis Technique

    Science.gov (United States)

    Yusuf, Gbadebo; Babatola, Babatunde Keji; Ishola, Abdulahi Dimeji; Awodugba, Ayodeji O.; Solar cell Collaboration

    2016-03-01

    Transparent conducting antimony-doped tin oxide (ATO) films have been deposited on glass substrates by home made spray pyrolysis technique. The structural, electrical and optical properties of the ATO films have been investigated as a function of Sb-doping level and annealing temperature. The optimum target composition for high conductivity and low resistivity was found to be 20 wt. % SnSb2 + 90 wt. ATO. Under optimized deposition conditions of 450oC annealing temperature, electrical resistivity of 5.2×10-4 Ω -cm, sheet resistance of 16.4 Ω/sq, average optical transmittance of 86% in the visible range, and average optical band-gap of 3.34eV were obtained. The film deposited at lower annealing temperature shows a relatively rough, loosely bound slightly porous surface morphology while the film deposited at higher annealing temperature shows uniformly distributed grains of greater size. Keywords: Annealing, Doping, Homemade spray pyrolysis, Tin oxide, Resistivity

  6. A density-functional study on the electronic and vibrational properties of layered antimony telluride

    Science.gov (United States)

    Stoffel, Ralf P.; Deringer, Volker L.; Simon, Ronnie E.; Hermann, Raphaël P.; Dronskowski, Richard

    2015-03-01

    We present a comprehensive survey of electronic and lattice-dynamical properties of crystalline antimony telluride (Sb2Te3). In a first step, the electronic structure and chemical bonding have been investigated, followed by calculations of the atomic force constants, phonon dispersion relationships and densities of states. Then, (macroscopic) physical properties of Sb2Te3 have been computed, namely, the atomic thermal displacement parameters, the Grüneisen parameter γ, the volume expansion of the lattice, and finally the bulk modulus B. We compare theoretical results from three popular and economic density-functional theory (DFT) approaches: the local density approximation (LDA), the generalized gradient approximation (GGA), and a posteriori dispersion corrections to the latter. Despite its simplicity, the LDA shows excellent performance for all properties investigated—including the Grüneisen parameter, which only the LDA is able to recover with confidence. In the absence of computationally more demanding hybrid DFT methods, the LDA seems to be a good choice for further lattice dynamical studies of Sb2Te3 and related layered telluride materials.

  7. Exploring the thermoelectric and magnetic properties of uranium selenides: Tl2Ag2USe4 and Tl3Cu4USe6

    Science.gov (United States)

    Azam, Sikander; Khan, Saleem Ayaz; Din, Haleem Ud; Khenata, Rabah; Goumri-Said, Souraya

    2016-09-01

    The electronic, magnetic and thermoelectric properties of Tl2Ag2USe4 and Tl3Cu4USe6 compounds were investigated using the full potential linear augmented plane wave (FP-LAPW) method based on the density functional theory (DFT). The exchange correlation was treated with the generalized gradient approximation plus optimized effective Hubbard parameter and spin-orbit coupling (GGA+U+SOC). The present uranium selenides show narrow direct energy band gap values of 0.7 and 0.875 eV for Tl2Ag2USe4 and Tl3Cu4USe6 respectively. For both selenides U-d/f states are responsible for electrical transport properties. Uranium atoms were the most contributors in the magnetic moment compared to other atoms and show ferromagnetic nature. The spin density isosurfaces show the polarization of neighboring atoms of Uranium, such as silver/copper and selenium. Thermoelectric calculations reveal that Tl3Cu4USe6 is more suitable for thermoelectric device applications than Tl2Ag2USe4.

  8. Non-Stoichiometric Amorphous Indium Selenide Thin Films as a Buffer Layer for CIGS Solar Cells with Various Temperatures in Rapid Thermal Annealing.

    Science.gov (United States)

    Yoo, Myoung Han; Kim, Nam-Hoon

    2016-05-01

    The conventional structure of most of copper indium gallium diselenide (Culn(1-x)Ga(x)Se2, CIGS) solar cells includes a CdS thin film as a buffer layer. Cd-free buffer layers have attracted great interest for use in photovoltaic applications to avoid the use of hazardous and toxic materials. The RF magnetron sputtering method was used with an InSe2 compound target to prepare the indium selenide precursor. Rapid thermal annealing (RTA) was conducted in ambient N2 gas to control the concentration of volatile Se from the precursor with a change in temperature. The nature of the RTA-treated indium selenide thin films remained amorphous under annealing temperatures of ≤ 700 degrees C. The Se concentration of the RTA-treated specimens demonstrated an opposite trend to the annealing temperature. The optical transmittance and band gap energies were 75.33% and 2.451-3.085 eV, respectively, and thus were suitable for the buffer layer. As the annealing temperature increased, the resistivity decreased by an order-of-magnitude from 10(4) to 10(1) Ω-cm. At lower Se concentrations, the conductivity abruptly changed from p-type to n-type without crystallite formation in the amorphous phase, with the carrier concentration in the order of 10(17) cm(-3). PMID:27483873

  9. Spray pyrolysis of tin selenide thin-film semiconductors: the effect of selenium concentration on the properties of the thin films

    Institute of Scientific and Technical Information of China (English)

    M.R.Fadavieslam; M.M.Bagheri-Mohagheghi

    2013-01-01

    Thin films of tin selenide (SnxSey) with an atomic ratio ofr =[x/y] =0.5,1 and 1.5 were prepared on a glass substrate at T =470 ℃ using a spray pyrolysis technique.The initial materials for the preparation of the thin films were an alcoholic solution consisting of tin chloride (SnCl4· 5H2O) and selenide acide (H2SeO3).The prepared thin films were characterized by X-ray diffraction (XRD),scanning electron microscopy,scanning tunneling microscopy,scanning helium ion microscopy,and UV-vis spectroscopy.The photoconductivity and thermoelectric effects of the Snx Seythin films were then studied.The Snx Sey thin films had a polycrystalline structure with an almost uniform surface and cluster type growth.The increasing atomic ratio ofr in the films,the optical gap,photosensitivity and Seebeck coefficient were changed from 1.6 to 1.37 eV,0.01 to 0.31 and-26.2 to-42.7 mV/K (at T =350 K),respectively.In addition,the XRD patterns indicated intensity peaks in r =1 that corresponded to the increase in the SnSe and SnSe2 phases.

  10. Gold and Antimony Mixed Flotation on a Micrite Gold Antimony ore in Guizhou%贵州某泥晶灰岩型含锑金矿金锑混浮试验

    Institute of Scientific and Technical Information of China (English)

    石贵明; 周意超

    2015-01-01

    贵州某泥晶灰岩型含锑金矿石为块状构造,金属矿物主要为黄铁矿、针铁矿,含量小于1%,非金属矿物以方解石为主,另有少量石英、有机质等;金含量为6.04 g/t,显微镜下未见自然金粒,74.34%的金赋存在硫化矿中,游离金仅占总金的7.14%;硅酸盐、碳酸盐包裹金分别占11.96%和6.56%;锑主要以辉锑矿的形式存在。为高效、低成本回收矿石中的金、锑,对混合浮选工艺进行了试验研究。结果表明,在一段磨矿细度为-0.074 mm占71%的情况下1粗2扫混浮、尾矿再磨细度为-0.074 mm占92.7%的情况下再1粗2扫混浮、两粗精矿合并后3次精选、中矿顺序返回流程处理,最终获得了金品位为47.60 g/t、锑品位为9.81%、金回收率为76.68%、锑回收率为85.22%的金锑混合精矿,金锑混浮效果较理想。尾矿中金的回收及金锑分离工艺研究将另文介绍。%The micrite type antimony-containing gold ore in Guizhou is in blocky construction. Its metallic minerals are mainly pyrite and goethite,with content of less than 1%. Non-metallic minerals are calcite,and few of quartz,organic matter, etc. It contains gold of 6. 04 g/t,and natural gold grains were not seen in microscope,74. 34% of the gold occurred in sulfide ore,free gold accounted for only 7. 14%,wrapped gold in silicate and carbonate accounted for 11. 96% and 6. 56% respective-ly. Antimony mainly existed in the form of stibnite. Bulk flotation process was studied to make high efficient recovery of gold and antimony at low costs. The results indicated that,at the grinding fineness of 71% passing 0. 074 mm,through one roughing and two scavenging bulk flotation,one roughing and two scavenging bulk flotation after regrinding the tailings to 92. 7% passing 0. 074 mm,three cleaning flotation for the two mixed rough concentrate,and then middles back to the flow-sheet in turn,rough gold-antimony concentrate with gold grade of 47. 60 g

  11. 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

    In solution antimony exists either in the pentavalent or trivalent oxidation state. As Sb(III) is more toxic than Sb(V), it is important to be able to perform a quantitative speciation analysis of Sb’s oxidation state. The most commonly applied chromatographic methods used for this redox speciation...... analysis do, however, often show a low chromatographic Sb recovery when samples of environmental or biological origin are analysed. In this study we explored basal chemistry of antimony and found that formation of macromolecules, presumably oligomeric and polymeric Sb(V) species, is the primary cause...... 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...

  12. a Study of Volatile Precursors for the Growth of Cadmium Sulphide and Cadmium Selenide by Metal Organic Chemical Vapour Deposition.

    Science.gov (United States)

    Beer, Michael P.

    Available from UMI in association with The British Library. The wide-band-gap semiconductors, cadmium sulphide and cadmium selenide, may be grown by Metal Organic Chemical Vapour Deposition (MOCVD). This method typically involves the reaction of gaseous streams of Me_2 Cd and H_2Y (Y = S, Se) over a heated substrate (usually gallium arsenide) on which the desired compound is grown as an epitaxial layer. Unfortunately, the precursors start to react in the cold zone of the reactor, that is before they reach the heated substrate. This problem is known as prereaction. The problem of prereaction is partially reduced by the use of adducts of dimethyl cadmium in place of the free dialkyl compound although the mechanism by which such adducts block prereaction is unknown. Accordingly, a study of adducts of dimethyl cadmium was undertaken with a view to determining their properties in all phases. The adduct of Me_2Cd with 2,2^ '-bipyridyl was found to be monomeric in the solid state while that with 1,4-dioxane, a volatile compound used for prereaction reduction, was found to be polymeric. A study of adducts in the gas phase using mass spectrometry and gas phase Fourier transform infrared spectroscopy gave no evidence to suggest there is any gas phase association between 1,4-dioxane and dimethyl cadmium. With the 2,2 ^'-bipyridyl adduct some evidence for partial retention of coordinate bonds upon sublimation was obtained. The solid adduct of Me _2Cd with N,N,N^' ,N^'-tetramethylethylenediamine (TMEDA) was prepared as it was hoped that the flexibility of the aliphatic Lewis base would permit the formation of an adduct containing strong co-ordinate bonds which would remain intact upon sublimation. Using gas phase electron diffraction, the structure of the adduct of Me_2Cd and TMEDA was determined. It was shown to exist in the gas phase purely as the associated monomeric species. The adduct was then employed for the growth of CdS and CdSe in an industrial MOCVD apparatus. The

  13. Minerogenetic Mechanism of the Songxi Silver—Antimony Deposit of Northeastern Guangdong—Ore—Controlling Role of Organic Matter

    Institute of Scientific and Technical Information of China (English)

    胡凯; 肖振宇; 等

    1999-01-01

    Organic geochemistry and comparisons of characteristics of the organic matter in wall rocks of the ore-controlling strata and ores of the Lower Jurassic Songling black shale formation and the related Songxi silver-antimony deposit of northeastern Guangdong have been studied in this paper.The results show that the Lower Jurassic Songling shale formation is a suite of biologic-rich and organic-rich ore-bearing marine sedimentary rocks.Micro-components of the organic matter in the Songling black shale formation consists primarily of algae,amorphous marine kerogen,solid bitument,and pyrobitument.The thermal evolution of organic matter is at the over-maturity stage.There is a general positive correlation between total organic carbon(CO)and metallogenetic elements such as Ag and Sb in the black shale formation.Organic matter in the host rocks in the Songxi ore deposit played a role in controlling the silver-antimony depositing environment during the forming process of the black shale ore-bearing formation.In the absence of vitrinite,the relative level of thermal maturity calculated by solid bitument reflectance indicates that the ore-forming temperatute of the Songxi silver-antimony deposit was about 150-170℃,which was considered as an epithermally reworked ore deposit.The roles of organic matter in the formation of the Sonxi ore deposit are a primitive accumulation of the metallogenetic elements(Ag,Sb) in the sea-water cycle system for ore source and a concentration of metals by ion exchange of chelation as well as reductionn of the oxidzed metals.

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

    Science.gov (United States)

    Robayo, Marta L.; Lopez, Myriam C.; Daza, Carlos D.; Bedoya, Angela; Mariño, Maria L.; Saavedra, Carlos H.

    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 antimonial derivatives as treatment for ACL show a healing rate of about 75% and reasons for treatment failure are not well known. Methods 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. Results 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). Conclusion 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

  15. Cobalt doped antimony oxide nano-particles based chemical sensor and photo-catalyst for environmental pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Jamal, Aslam [Centre for Advanced Materials and Nano-Engineering (CAMNE) and Department of Chemistry, Faculty of Sciences and Arts, Najran University, P. O. Box 1988, Najran 11001 (Saudi Arabia); Rahman, Mohammed M. [Center of Excellence for Advanced Materials Research (CEAMR), King Abdulaziz University, P.O. Box 80203, Jeddah 21589 (Saudi Arabia); Chemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589 (Saudi Arabia); Khan, Sher Bahadar, E-mail: drkhanmarwat@gmail.com [Center of Excellence for Advanced Materials Research (CEAMR), King Abdulaziz University, P.O. Box 80203, Jeddah 21589 (Saudi Arabia); Chemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589 (Saudi Arabia); Faisal, Mohd. [Centre for Advanced Materials and Nano-Engineering (CAMNE) and Department of Chemistry, Faculty of Sciences and Arts, Najran University, P. O. Box 1988, Najran 11001 (Saudi Arabia); Akhtar, Kalsoom [Division of Nano Sciences and Department of Chemistry, Ewha Womans University, Seoul 120-750 (Korea, Republic of); Rub, Malik Abdul; Asiri, Abdullah M.; Al-Youbi, Abdulrahman O. [Center of Excellence for Advanced Materials Research (CEAMR), King Abdulaziz University, P.O. Box 80203, Jeddah 21589 (Saudi Arabia); Chemistry Department, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589 (Saudi Arabia)

    2012-11-15

    Graphical abstract: A dichloromethane chemical sensor using cobalt antimony oxides has been fabricated. This sensor showed high sensitivity and will be a useful candidate for environmental and health monitoring. Also it showed high photo-catalytic activity and can be a good candidate as a photo-catalyst for organic hazardous materials. Highlights: Black-Right-Pointing-Pointer Reusable chemical sensor. Black-Right-Pointing-Pointer Green environmental and eco-friendly chemi-sensor. Black-Right-Pointing-Pointer High sensitivity. Black-Right-Pointing-Pointer Good candidate for environmental and health monitoring. - Abstract: Cobalt doped antimony oxide nano-particles (NPs) have been synthesized by hydrothermal process and structurally characterized by utilizing X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and Fourier transforms infrared spectrophotometer (FT-IR) which revealed that the synthesized cobalt antimony oxides (CoSb{sub 2}O{sub 6}) are well crystalline nano-particles with an average particles size of 26 {+-} 10 nm. UV-visible absorption spectra ({approx}286 nm) were used to investigate the optical properties of CoSb{sub 2}O{sub 6}. The chemical sensing of CoSb{sub 2}O{sub 6} NPs have been primarily investigated by I-V technique, where dichloromethane is used as a model compound. The analytical performance of dichloromethane chemical sensor exhibits high sensitivity (1.2432 {mu}A cm{sup -2} mM{sup -1}) and a large linear dynamic range (1.0 {mu}M-0.01 M) in short response time (10 s). The photo catalytic activity of the synthesized CoSb{sub 2}O{sub 6} nano-particles was evaluated by degradation of acridine orange (AO), which degraded 58.37% in 200 min. These results indicate that CoSb{sub 2}O{sub 6} nano-particles can play an excellent research impact in the environmental field.

  16. Comparative Efficacies of Two Antimony Regimens To Treat Leishmania braziliensis-Induced Cutaneous Leishmaniasis in Rhesus Macaques (Macaca mulatta)▿

    Science.gov (United States)

    Grimaldi, G.; Porrozzi, R.; Friedrich, K.; Teva, A.; Marchevsky, R. S.; Vieira, F.; Miekeley, N.; Paumgartten, F. J. R.

    2010-01-01

    This study compared the efficacies of two N-methylglucomine antimoniate (MA) dose regimens for treating macaques with Leishmania braziliensis-induced chronic skin disease. Whereas all animals treated with the full dose (20 mg MA/kg/day) were cured, 50% of the monkeys receiving a low-dose regimen (5 mg MA/kg/day) relapsed. The antimony concentrations in macaque plasma and tissue samples were greater in the full-dose group than in that receiving a subtherapeutic MA regimen. Our data also suggest the presence of drug-induced hepatic pathology. PMID:19822700

  17. Influence of antimony on the mechanical properties and gas content of alloy AlSi6Cu4

    OpenAIRE

    D. Medlen; D. Bolibruchova

    2011-01-01

    Aluminium alloys based on Al-Si are used in automotive and aerospace industries. AlSi6Cu4 alloy is used the complicated castings, whichmust comply high strength requirements. Strength characteristics can also be affected by the modifiers: Na, Sr, Sb. In the li terature ismentioned, that AlSi6Cu4 modified by sodium and strontium has negative effect - increases of the gas absorption. Modification of AlSi6Cu4 alloy by antimony, is still not mentioned in the literature. The article gives the effe...

  18. The influence of remelting on the properties of AlSi6Cu4 alloy modified by antimony

    Directory of Open Access Journals (Sweden)

    D. Medlen

    2012-01-01

    Full Text Available The paper deals with the problem of multiple remelting influence on AlSi6Cu4 alloy modified by antimony on chosen mechanical characteristics, microstructure and gas content. This foundry alloy is used mostly in automotive industry. Foundry Aluminum-Silicon alloys are also used in number of industrial weight sensitive applications because of their low weight and very good castability and good mechanical properties. Modifiers are usually added to molten aluminum-silicon alloys to refine the eutectic phase particle shape and improve the mechanical properties of the final cast products and Al-Si alloys cast properties.

  19. Flow analysis-hydride generation-gas phase derivative molecular absorption spectrophotometric determination of antimony in antileishmanial drugs

    Directory of Open Access Journals (Sweden)

    Máximo Gallignani

    2009-01-01

    Full Text Available In the present work, the development of a method based on the coupling of flow analysis (FA, hydride generation (HG, and derivative molecular absorption spectrophotometry (D-EAM in gas phase (GP, is described in order to determine total antimony in antileishmanial products. Second derivative order (D²224nm of the absorption spectrum (190 - 300 nm is utilized as measurement criterion. Each one of the parameters involved in the development of the proposed method was examined and optimized. The utilization of the EAM in GP as detection system in a continuous mode instead of atomic absorption spectrometry represents the great potential of the analytic proposal.

  20. Effect of external energy on atomic, crystalline and powder characteristics of antimony and bismuth powders

    Indian Academy of Sciences (India)

    Vikram V Dabhade; Rama Mohan R Tallapragada; Mahendra Kumar Trivedi

    2009-10-01

    Next to atoms and molecules the powders are the smallest state of matter available in high purities and large quantities. The effect of any external energy on the shape, morphology and structure can thus be studied with relative ease. The present investigation deals with the effect of a non-contact external energy on the powders of antimony and bismuth. The characteristics of powders treated by external energy are compared with the as received powders (control). The average particle sizes, 50 and 99, the sizes below which 99% of the particles are present showed significant increase and decrease indicating that the energy had caused deformation and fracture as if the powders have been subjected to high energy milling. To be able to understand the reasons for these changes the powders are characterized by techniques such as X-ray diffraction (XRD), surface area determination (BET), thermal analytical techniques such as DTA–DTG, DSC–TGA and SDTA and scanning electron microscopy (SEM). The treated powder samples exhibited remarkable changes in the powder characteristics at all structural levels starting from polycrystalline particles, through single crystal to atoms. The external energy had changed the lattice parameters of the unit cell which in turn changed the crystallite size and density. The lattice parameters are then used to compute the weight and effective nuclear charge of the atom which showed significant variation. It is speculated that the external energy is acting on the nucleus through some reversible weak interaction of larger cross section causing changes in the proton to neutron ratios. Thus the effect is felt by all the atoms, and hence the unit cell, single crystal grain and grain boundaries. The stresses generated in turn may have caused deformation or fracture of the weak interfaces such as the crystallite and grain boundaries.

  1. Contamination of bottled waters with antimony leaching from polyethylene terephthalate (PET) increases upon storage.

    Science.gov (United States)

    Shotyk, William; Krachler, Michael

    2007-03-01

    Antimony concentrations were determined in 132 brands of bottled water from 28 countries. Two of the brands were at or above the maximum allowable Sb concentration for drinking water in Japan (2 microg/L). Elevated concentrations of Sb in bottled waters are due mainly to the Sb2O3 used as the catalyst in the manufacture of polyethylene terephthalate (PET(E)). The leaching of Sb from PET(E) bottles shows variable reactivity. In 14 brands of bottled water from Canada, Sb concentrations increased on average 19% during 6 months storage at room temperature, but 48 brands of water from 11 European countries increased on average 90% under identical conditions. A mineral water from France in PET(E), purchased in Germany, yielded 725 ng/L when first tested, but 1510 ng/L when it was stored for 6 months at room temperature; the same brand of water, purchased in Hong Kong, yielded 1990 ng/L Sb. Pristine groundwater containing 1.7+/-0.4 ng/L Sb (n = 6) yielded 26.6+/-2.3 ng/L Sb (n = 3) after storage in PET(E) bottles from Canada for 6 months versus 281+/-38 ng/L Sb (n = 3) in PET(E) bottles from Germany. Tap water bottled commercially in PET(E) in December 2005 contained 450+/-56 ng/L Sb (n = 3) versus 70.3+/-0.3 ng/L Sb (n = 3) when sampled from a household faucet in the same village (Bammental, Germany), and 25.7+/-1.5 ng/L Sb (n = 3) from a local artesian flow. PMID:17396641

  2. Uptake, translocation and transformation of antimony in rice (Oryza sativa L.) seedlings.

    Science.gov (United States)

    Cai, Fei; Ren, Jinghua; Tao, Shu; Wang, Xilong

    2016-02-01

    Antimony (Sb), as a toxic metalloid, has been gaining increasing research concerns due mainly to its severe pollution in many places. Rice has been identified to be the dominant intake route of Sb by residents close to the Sb mining areas. A hydroponic experiment was conducted to investigate the difference in uptake, translocation and transformation of Sb in rice seedlings of four cultivars exposed to 0.2 or 1.0 mg/L of Sb(V). The results showed that mass concentration of iron plaque (mg/kg FW) formed at the root surfaces of cultivar N was the highest among all tested cultivars at both low and high exposure levels of Sb(V). The accumulated Sb concentration in iron plaque significantly increased with an increase in mass concentration of iron plaque formed at the rice root. The total amount of iron plaque (mg/pot) at rice root generally increased with increasing exposed Sb(V) concentration, which was closely associated with the increasing lipid peroxidation in roots. Concentration percentage of Sb in rice root significantly reduced as the corresponding value in the iron plaque increased, suggesting that iron plaque formation strongly suppressed uptake of Sb by rice root. Sb concentration in rice tissues followed an order: root > stem, leaf. The japonica rice (cultivars N and Z) exhibited a stronger translocation tendency of Sb from root to stem than indica hybrid rice (cultivars F and G). Translocation of Sb from root of cultivar F to its stem and leaf was sharply enhanced with increasing Sb exposure concentration. Sb(V) could be reduced to Sb(III) in rice tissues, especially in stems (10-26% of the total Sb). For the sake of food safety, the difference in uptake, translocation and transformation of Sb in rice species planted in Sb-contaminated soils should be taken into consideration.

  3. Association of drinking-water source and use characteristics with urinary antimony concentrations.

    Science.gov (United States)

    Makris, Konstantinos C; Andra, Syam S; Herrick, Lisa; Christophi, Costas A; Snyder, Shane A; Hauser, Russ

    2013-03-01

    Environmental factors, such as storage time, frequency of bottle reuse and temperature, have been shown to facilitate antimony (Sb) leaching from water- and food-packaging materials. The globally escalating consumption of water packaged in Sb-containing bottles, such as that of polyethylene terephthalate (PET), could increase human daily Sb doses. This study set out to investigate the relationship between drinking-water source, use characteristics, and urinary Sb concentrations (U-Sb) accompanied with survey responses of a healthy (n=35) Cypriot participant pool. One spot urine sample was collected during administration of questionnaire, while a second spot urine sample was collected from the same individual about 7 days later. Urinary and water Sb concentrations were measured with an inductively coupled plasma mass spectrometer. Survey responses showed that bottled water summed over various volumes and plastic types, such as polycarbonate and PET contributed to an average 61% of daily water consumption. Water sources such as tap, mobile stations (explained in a following section), and well water contributed to 24%, 14%, and 2% of an individual's daily water consumption pattern, respectively. Average daily potable water use of both bottled and tap water by individuals consisted of 65% drinking-water, while the remaining 35% was water used for preparing cold and hot beverages, such as, tea, coffee, and juices. A significant (P=0.02) association between per capita water consumption from PET bottles and urinary creatinine-unadjusted concentrations was observed, but this relationship did not remain after inclusion of covariates in a multivariate regression model. In the creatinine-adjusted regression model, only gender (female) was a significant (P<0.01) predictor of U-Sb, after adjusting for several covariates. It is proposed that consumption data collection on various water uses and sources among individuals could perhaps decrease the uncertainty associated with

  4. Effects of Residual Elements Arsenic, Antimony, and Tin on Surface Hot Shortness

    Science.gov (United States)

    Yin, Lan; Sridhar, Seetharaman

    2011-10-01

    Scrap-based electric arc furnace (EAF) steelmaking is limited by a surface cracking problem in the recycled steel products, which is known as surface hot shortness. This problem originates from the excessive amount of copper (Cu) in the steel scrap, which enriches during the oxidation of iron (Fe) and consequently melts and penetrates into the austenite grain boundaries. In this article, the effects of arsenic (As), antimony (Sb), and tin (Sn) on surface hot shortness were investigated. A series of Fe-0.3 wt pct Cu- x wt pct (As, Sb, or Sn) alloys with x content ranging from 0.06 to 0.10 wt pct was oxidized in air at 1423 K (1150 °C) for 60, 300, and 600 seconds inside the chamber of a thermogravimety analyzer (TGA) where heat is supplied through infrared radiation. Scanning electron microscopy (SEM) investigations show that (1) the presence of Sb and Sn results in severe grain boundary cracking, whereas the presence of As does not, (2) open cracks with Fe oxides were found beneath the oxide/metal interface in the Sb and Sn alloys, and (3) the oxide/metal interfaces for all As, Sb, and Sn alloys are planar. Penetration experiments of pure Cu and Cu-30 wt pct Sn liquid were also conducted in the chamber of a hot-stage confocal laser scanning microscopy (CLSM) in nonoxidizing atmosphere: (1) on the Fe-35 wt pct manganese (Mn) alloys to study the correlation between cracking and grain boundary characters, and (2) on the pure Fe substrates to exclude the bulk segregation effects of Sn on grain boundary cracking. It was found that grain boundary cracking rarely took place on low-energy grain boundaries. The results also suggest that the bulk segregation of Sn in the substrate is not necessary to promote significant grain boundary cracking, and as long as the liquid phase contains Sn, it will be highly embrittling.

  5. Green and red fluorescence upconversion in neodymium-doped low phonon antimony glasses

    International Nuclear Information System (INIS)

    A new K2O-B2O3-Sb2O3 (KBS) glass system having low phonon energy (about 600 cm-1) doped with Nd3+ ions has been developed. Infrared reflection spectroscopic (IRRS) studies have been employed to establish its low phonon energy. Ultraviolet-visible-near infrared (UV-vis-NIR) absorption and photoluminescence upconversion properties with special emphasis on the spectrochemistry of the 15K2O-15B2O3-70Sb2O3 (mol%) glass have been studied doping with different concentrations (0.1-1.0 wt%) of Nd2O3. UV-vis-NIR absorption band positions have been justified with quantitative calculation of nephelauxetic parameter and covalent bonding characteristics of the host. NIR to visible upconversion has been investigated by exciting at 805 nm at room temperature. Two upconverted bands originating from the 4G7/2 → 4I9/2 and 4G7/2 → 4I13/2 transitions are found to be centered at 540 nm (green, medium) and 650 nm (red, strong), respectively. These bands have been explained from the evaluation of the absorption and excitation spectra. The upconversion processes have been explained by the excited state absorption (ESA), energy transfer (ET), cooperative energy transfer (CET) and cross-relaxation (CR) mechanisms involving population of the metastable (storage) energy level (4G7/2) by effects of multiphonon deexcitation and thermal population. It is evident from the IRRS study that the upconversion phenomena are expedited by the low multiphonon relaxation rate in antimony glasses owing to their low phonon energy (602 cm-1, the main and highest intensity Sb-O-Sb stretching band) which is very close to that of fluoride glasses (500-600 cm-1).

  6. EPR, optical absorption and luminescence studies of Cr3+-doped antimony phosphate glasses

    Science.gov (United States)

    De Vicente, F. S.; Santos, F. A.; Simões, B. S.; Dias, S. T.; Siu Li, M.

    2014-12-01

    Antimony phosphate glasses (SbPO) doped with 3 and 6 mol% of Cr3+ were studied by Electron Paramagnetic Resonance (EPR), UV-VIS optical absorption and luminescence spectroscopy. The EPR spectra of Cr3+-doped glasses showed two principal resonance signals with effective g values at g = 5.11 and g = 1.97. UV-VIS optical absorption spectra of SbPO:Cr3+ presented four characteristics bands at 457, 641, 675, and 705 nm related to the transitions from 4A2(F) to 4T1(F), 4T2(F), 2T1(G), and 2E(G), respectively, of Cr3+ ions in octahedral symmetry. Optical absorption spectra of SbPO:Cr3+ allowed evaluating the crystalline field Dq, Racah parameters (B and C) and Dq/B. The calculated value of Dq/B = 2.48 indicates that Cr3+ ions in SbPO glasses are in strong ligand field sites. The optical band gap for SbPO and SbPO:Cr3+ were evaluated from the UV optical absorption edges. Luminescence measurements of pure and Cr3+-doped glasses excited with 350 nm revealed weak emission bands from 400 to 600 nm due to the 3P1 → 1S0 electronic transition from Sb3+ ions. Cr3+-doped glasses excited with 415 nm presented Cr3+ characteristic luminescence spectra composed by two broad bands, one band centered at 645 nm (2E → 4A2) and another intense band from 700 to 850 nm (4T2 → 4A2).

  7. Metagenomic approach reveals variation of microbes with arsenic and antimony metabolism genes from highly contaminated soil.

    Directory of Open Access Journals (Sweden)

    Jinming Luo

    Full Text Available Microbes have great potential for arsenic (As and antimony (Sb bioremediation in heavily contaminated soil because they have the ability to biotransform As and Sb to species that have less toxicity or are more easily removed. In this study, we integrated a metagenomic method with physicochemical characterization to elucidate the composition of microbial community and functional genes (related to As and Sb in a high As (range from 34.11 to 821.23 mg kg-1 and Sb (range from 226.67 to 3923.07 mg kg-1 contaminated mine field. Metagenomic analysis revealed that microbes from 18 phyla were present in the 5 samples of soil contaminated with high As and Sb. Moreover, redundancy analysis (RDA of the relationship between the 18 phyla and the concentration of As and Sb demonstrated that 5 phyla of microbes, i.e. Actinobacteria, Firmicutes, Nitrospirae, Tenericutes and Gemmatimonadetes were positively correlated with As and Sb concentration. The distribution, diversity and abundance of functional genes (including arsC, arrA, aioA, arsB and ACR3 were much higher for the samples containing higher As and Sb concentrations. Based on correlation analysis, the results showed a positive relationship between arsC-like (R2 = 0.871 and aioA-like (R2 = 0.675 gene abundance and As concentration, and indicated that intracellular As(V reduction and As(III oxidation could be the dominant As detoxification mechanism enabling the microbes to survive in the environment. This study provides a direct and reliable reference on the diversity of microbial community and functional genes in an extremely high concentration As- and Sb-contaminated environment.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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

    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...

  13. 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. PMID:19924925

  14. 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

  15. 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.

  16. Green and red fluorescence upconversion in neodymium-doped low phonon antimony glasses

    Energy Technology Data Exchange (ETDEWEB)

    Som, Tirtha [Glass Technology Laboratory, Central Glass and Ceramic Research Institute (Council of Scientific and Industrial Research), 196 Raja S.C. Mullick Road, Kolkata 700032 (India); Karmakar, Basudeb [Glass Technology Laboratory, Central Glass and Ceramic Research Institute (Council of Scientific and Industrial Research), 196 Raja S.C. Mullick Road, Kolkata 700032 (India)], E-mail: basudebk@cgcri.res.in

    2009-05-12

    A new K{sub 2}O-B{sub 2}O{sub 3}-Sb{sub 2}O{sub 3} (KBS) glass system having low phonon energy (about 600 cm{sup -1}) doped with Nd{sup 3+} ions has been developed. Infrared reflection spectroscopic (IRRS) studies have been employed to establish its low phonon energy. Ultraviolet-visible-near infrared (UV-vis-NIR) absorption and photoluminescence upconversion properties with special emphasis on the spectrochemistry of the 15K{sub 2}O-15B{sub 2}O{sub 3}-70Sb{sub 2}O{sub 3} (mol%) glass have been studied doping with different concentrations (0.1-1.0 wt%) of Nd{sub 2}O{sub 3}. UV-vis-NIR absorption band positions have been justified with quantitative calculation of nephelauxetic parameter and covalent bonding characteristics of the host. NIR to visible upconversion has been investigated by exciting at 805 nm at room temperature. Two upconverted bands originating from the {sup 4}G{sub 7/2} {yields} {sup 4}I{sub 9/2} and {sup 4}G{sub 7/2} {yields} {sup 4}I{sub 13/2} transitions are found to be centered at 540 nm (green, medium) and 650 nm (red, strong), respectively. These bands have been explained from the evaluation of the absorption and excitation spectra. The upconversion processes have been explained by the excited state absorption (ESA), energy transfer (ET), cooperative energy transfer (CET) and cross-relaxation (CR) mechanisms involving population of the metastable (storage) energy level ({sup 4}G{sub 7/2}) by effects of multiphonon deexcitation and thermal population. It is evident from the IRRS study that the upconversion phenomena are expedited by the low multiphonon relaxation rate in antimony glasses owing to their low phonon energy (602 cm{sup -1}, the main and highest intensity Sb-O-Sb stretching band) which is very close to that of fluoride glasses (500-600 cm{sup -1})

  17. Novel organo-colloidal synthesis, optical properties, and structural analysis of antimony sesquioxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Validzic, Ivana Lj., E-mail: validzic@vinca.rs; Abazovic, Nadica D.; Mitric, Miodrag [University of Belgrade, ' Vinca' Institute of Nuclear Sciences (Serbia); Lalic, Milan V. [Universidade Federal de Sergipe, Departamento de Fisica (Brazil); Popovic, Zoran S. [University of Belgrade, ' Vinca' Institute of Nuclear Sciences (Serbia); Vukajlovic, Filip R. [' Vinca' Institute of Nuclear Sciences (Serbia)

    2013-01-15

    We report the novel colloidal syntheses in organic media of antimony sesquioxide ( Sb{sub 2}O{sub 3} ) spherical nanoparticles (30-250 nm) and octahedron micro- and nanocrystals (100nm - 4{mu}) depending on the synthetic method conditions. It is observed that small differences in the synthetic procedure cause large differences in the very changeable morphology. The structure of Sb{sub 2}O{sub 3} powders was refined down to the R-factors of 9.57, 7.44, 9.19, 9.78, and 8.30 %. The refinement showed that Sb{sub 2}O{sub 3} powder belongs to the cubic crystal type with space group Fd 3-bar m (No. 227). The values of estimated standard deviations, as well as reliability factors, confirmed that the structure of Sb{sub 2}O{sub 3} was well refined. Ultraviolet and visible (UV-Vis) absorption spectroscopy and diffuse reflectance measurements (DRS) reveal that the optical band gap energies found for the Sb{sub 2}O{sub 3} octahedrons and nanoparticles, micro- and nanocrystals, respectively, are quite independent of the synthetic method conditions and synthesized morphology and is found to be between 4.1-4.4 eV. No peaks in both photoluminescence (PL) emission and excitation spectra have been observed for a broad spectral range, typical for this material. In order to discriminate between conflicting experimental results concerning the band gap energy of this compound, we investigated theoretically the electronic structure and optical properties of one of the cubic sesquioxide Sb{sub 2}O{sub 3} samples synthesized here. This has been done on the basis of density functional theory (DFT) with the generalized gradient approximation (GGA) and improved version of exchange potential suggested recently by Tran and Blaha (TB-mBJ). The main characteristic of the calculated TB-mBJ electronic structure is the significant improvement of the band gap value, which is in perfect agreement with our experimental measurements. The real and imaginary parts of the dielectric tensor are also

  18. 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

  19. Growth, photosynthesis, and defense mechanism of antimony (Sb)-contaminated Boehmeria nivea L.

    Science.gov (United States)

    Chai, Li-Yuan; Mubarak, Hussani; Yang, Zhi-Hui; Yong, Wang; Tang, Chong-Jian; Mirza, Nosheen

    2016-04-01

    Ramie (Boehmeria nivea L.) is the oldest cash fiber crop in China and is widely grown in antimony (Sb) mining areas. To evaluate the extent of Sb resistance and tolerance, the growth, tolerance index (TI), Sb content in plant parts and in Hoagland solution, bioaccumulation factor (BF), photosynthesis, and physiological changes in Sb-contaminated B. nivea (20, 40, 80, and 200 mg L(-1) Sb) grown hydroponically were investigated. The Sb tolerance and resistance of ramie were clearly revealed by growth inhibition, a TI between 13 and 99 %, non-significant changes in the maximum quantum efficiency of photosystem (F v /F m ), energy-harvesting efficiency (photosystem II (PSII)) and single-photon avalanche diode (SPAD) value, a significant increase in Sb in plant parts, BF >1, and an increase in catalase (CAT) and malondialdehyde (MDA) at 200 mg L(-1) Sb. Under increasing Sb stress, nearly the same non-significant decline in the maximum quantum efficiency of photosystem (F v /F m ), energy-harvesting efficiency (PSII), relative quantum yield of photosystem II (φPSII), and photochemical quenching (qP), except for F v /F m at 20 mg L(-1) Sb, were recorded. SPAD values for chlorophyll under Sb stress showed an increasing trend, except for a slight decrease, i.e., continuous increase in MDA, superoxide dismutase (SOD), peroxidase (POD), and CAT activities were suppressed under Sb addition up to 40 mg L(-1) Sb and the addition of Sb enhanced enzyme production at 80 and 200 mg L(-1) Sb. A continuous decrease in SOD, POD, and CAT up to 40 mg L(-1) Sb and enhancements at ≥80 mg L(-1), along with the continuous enhancement of MDA activity and inhibited biomass production, clearly reveal the roles of these enzymes in detoxifying Sb stress and the defense mechanism of ramie at 80 mg L(-1) Sb. Thus, B. nivea constitutes a promising candidate for Sb phytoremediation at mining sites. PMID:26711292

  20. Synthesis and Properties of Light-tolerant Organic Antimony%耐光型有机锑的合成及其性能研究

    Institute of Scientific and Technical Information of China (English)

    高勇; 韩永和; 李建丰; 袁余斌; 王爱红

    2014-01-01

    硫醇锑稳定剂由于其耐紫外光性能很差,在存储、运输和使用方面受到很大的限制。为解决这一问题,试探性以三氯化锑和巯基酯为原料,引入抗紫外线活性基团TBP-1(2,4-二羟基二苯甲酮),合成了“晒不黑”的有机锑热稳定剂。用红外光谱对产品结构进行了确认,光敏性实验表明其7周内不变色;静态热稳定性实验结果表明其与硫醇锑热稳定剂相当。%Because of its poor ultraviolet resistance , the storage , transportation and use of antimony mercaptide stabilizer was greatly limited.In order to solve this problem , a kind of synthesized organic antimony thermal stabilizer was prepared, which was light -tolerant with antimony trichloride , isooctyl thioglycollat as raw materials and TBP -1(2,4-dihydroxybenzophenone ) , with an anti-ultraviolet agent added in.The light-tolerant performance and thermal stability of product tested showed that the color of organic antimony as -synthesized was unchangeable when under the impact of direct sunlight for 7 weeks by infrared spectroscopy spectrum that was confirmed for structure of product , and the static experimental results showed that the thermal stability was nearly equivalent to antimony mercaptide.

  1. Research advances in microbial mechanism of antimony%微生物对锑的代谢机制研究进展

    Institute of Scientific and Technical Information of China (English)

    李明顺; 李洁; 王革娇

    2013-01-01

    锑(Sb)是一种自然界普遍存在的剧毒重金属,随着工业生产的日趋发展,我国部分地区土壤、水体及农产品受到严重的锑污染.作为环境污染物,锑中毒会导致人类心肌衰竭,肝坏死等疾病.自然界中的某些生物,特别是微生物却可以在极高锑浓度下生长,甚至可以利用这种元素作为能源物质,因此,微生物在锑的地球物质循环中起着重要的作用.研究生物对锑的代谢机制,对于保护环境与人体健康具有重要的现实意义.本文对锑在环境中的分布、污染状况、微生物对锑的代谢以及生物修复等方面的研究现状进行了综述.同时建议今后应加强以下三方面的研究:(1)筛选更多抗锑微生物或氧化锑的微生物;(2)发掘更多锑抗性基因或氧化基因;(3)开发锑污染土壤及水体的微生物修复技术.%Antimony (Sb) is a highly toxic heavy metal which widespreadly exists in nature.With the increasing development of industry,the soil,water and agricultural products are severely polluted by antimony in some regions of our country.As an environmental pollutant,antimony poisoning can lead to heart failure,human diseases such as liver necrosis.Some organisms in nature,especially the microorganisms can grow in the high concentration of antimony,and can even use the element as an energy material,so the microorganisms play an important role in the cycle of earth's materials.Study on metabolic mechanism of antimony has important practical significance to protect environment and human health.This study reviewed the researches of Sb distribution in the environment,the pollution status,microbial metabolism of antimony and bioremediation.At the same time it suggests that future researches should strengthen the following three aspects:(1) isolating more antimony resistance or antimony oxidizing microorganisms; (2) identifying more antimony resistant or oxidizing genes; (3) exploring microbial techniques to remediate

  2. 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

  3. Synthesis and characterization of nanostructured Mn(II) doped antimony-tin oxide (ATO) films on glass

    International Nuclear Information System (INIS)

    Sol–gel Mn(II) doped antimony tin oxide films were developed with precursor of atomic ratio range, Sn:Sb:Mn = 68–72:23–25:9–3. The X-ray diffraction patterns depict tetragonal cassiterite phase of SnO2. Transmission electron microscopy images suggest the nanostructured form of the doped materials. The increase in crystallite size with Mn(II) concentration is reflected by the larger band gap values (4.61–4.73 eV) arising from the excitonic transitions which also respond to PL emissions. Hall effect measurements show that the carrier concentration increases but mobility decreases for Mn(II) doping. Room temperature ferromagnetism with different saturation magnetic moments (Ms) has been observed for all dopant concentrations, 3–9 at%.

  4. The chemistry and behaviour of antimony in the soil environment with comparisons to arsenic: A critical review

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Susan C., E-mail: swilso24@une.edu.a [School of Environmental and Rural Science, University of New England, Armidale, NSW 2351 (Australia); Lockwood, Peter V., E-mail: peter.lockwood@une.edu.a [School of Environmental and Rural Science, University of New England, Armidale, NSW 2351 (Australia); Ashley, Paul M., E-mail: pashley@une.edu.a [School of Environmental and Rural Science, University of New England, Armidale, NSW 2351 (Australia); Tighe, Matthew, E-mail: mtighe2@une.edu.a [School of Environmental and Rural Science, University of New England, Armidale, NSW 2351 (Australia)

    2010-05-15

    This article provides a critical review of the environmental chemistry of inorganic antimony (Sb) in soils, comparing and contrasting findings with those of arsenic (As). Characteristics of the Sb soil system are reviewed, with an emphasis on speciation, sorption and phase associations, identifying differences between Sb and As behaviour. Knowledge gaps in environmentally relevant Sb data for soils are identified and discussed in terms of the limitations this imposes on understanding the fate, behaviour and risks associated with Sb in environmental soil systems, with particular reference to mobility and bioavailability. - A critical and comparative review of Sb and As chemistry and associations in soil systems identifies research directions needed for better understanding of risks.

  5. 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. PMID:26194244

  6. Conjugative plasmid in Corynebacterium flaccumfaciens subsp. oortii that confers resistance to arsenite, arsenate, and antimony(III)

    Energy Technology Data Exchange (ETDEWEB)

    Hendrick, C.A.; Haskins, W.P.; Vidaver, A.K.

    1984-07-01

    Gene transfer systems for phytopathogenic corynebacteria have not been reported previously. In this paper a conjugative 46-megadalton plasmid (pDG101) found in Corynebacterium flaccumfaciens subsp. oorii CO101 is described that mediates resistance to arsenite, arsenate, and antimony(III). Transfer of the plasmid from CO101 to four other strains from the C. flaccumfaciens group occurred between cells immobilized on nitrocellulose filters or on agar surfaces. Transconjugant strains expressed the same levels of metal resistance as the donor strain and were able to act as donor strains in subsequent matings. The physical presence of the plasmid was detected by agarose gel electrophoresis. Arsenite-sensitive derivatives of the donor and transconjugant strains were obtained after heat treatment; these were cured of pDG101.

  7. Construction of spongy antimony-doped tin oxide/graphene nanocomposites using commercially available products and its excellent electrochemical performance

    Science.gov (United States)

    Zhao, Xiaowei; Zhang, Jingwei; Zhang, Jiwei; Gong, Chunhong; Gu, Xiufang; Ma, Zhihua; Zhou, Jingfang; Yu, Laigui; Zhang, Zhijun

    2015-10-01

    We construct successfully a porous antimony-doped tin oxide (ATO)/nitrogen-doped graphene 3-dimensional (3D) frameworks (denoted as ATO/NG/TEPA; TEPA refers to tetraethylenepentamine) by a one-pot hydrothermal process, with which TEPA aqueous solution is adopted to easily re-disperse commercial ATO precursor forming a transparent hydrosol. The results show that TEPA plays a key role in the construction of ATO/NG/TEPA, not only acting as a peptization reagent to re-disperse ATO precursor nanoparticles, and as a linker to combine ATO with graphene sheets. The as-fabricated ATO/NG/TEPA hybrid as the negative electrode of lithium ion batteries exhibits excellent lithium storage capacity and cycling stability. With the advantage of easily re-dispersing commercial ATO, the present synthetic route may be put into use for the large-scale production of the titled nanocomposites as the anode material of lithium ion batteries.

  8. Fabrication of superhydrophobic and heat-insulating antimony doped tin oxide/polyurethane films by cast replica micromolding.

    Science.gov (United States)

    Feng, Jie; Huang, Baoyuan; Zhong, Mingqiang

    2009-08-01

    A novel process for fabricating superhydrophobic and heat-insulating polymeric nanocomposite films was developed. Briefly, antimony doped tin oxide (ATO) nanoparticles that commonly endow coats heat-insulating and transparent functions were mixed into commercial waterborne polyurethane (WPU) suspensions to obtain ATO/WPU suspensions, which were then cast onto poly(dimethylsiloxane) (PDMS) stamps replicated from fresh lotus leaves. After being dried and peeled off from stamps, ATO/PU films with superhydrophobic surface and heat-insulating property were created, while PU films without ATO only showed high hydrophobicity. Scanning electron microscopy (SEM) imaging showed the surface of ATO/PU superhydrophobic films had unique micro- and nano-structures similar with those on the lotus leaf. On the contrary, no obvious nano-structures were found on the surface of pure PU films, demonstrating mixing functional nanoparticles into polymers is a necessary and feasible step in creating superhydrophobic and functional films by replica molding method. PMID:19394955

  9. lVIICROSTRUCTURE AND EUTECTIC MORPHOLOGY OF AL-12.5°/o Si ALLOY REFINED WITH ANTIMONY

    Directory of Open Access Journals (Sweden)

    Funda Kahraman

    2007-01-01

    Full Text Available Modification of Al-Si cast alloys can be achieved in two different ways, namely by additions of certain eleınents orwith rapid cooling rate. Modifications of the Al-Si al1oys are carried out extensivcly in industry to improve themechanical properties, particularly ductility. In this study, the effects of antiınony addition.s and growth rate on theınicrostructure and eutectic morphology on the directionally solidified Al- 1 2.5°/o Si cutectic all oy has beeninvestigated. The results showed that antimony can be identified as a grain refıner. Over modification occurs in Al-12.5 °/oSi alloy when modifier is present in the amount of 1 %Sb results in AISb compound.

  10. 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.

  11. Synthesis, crystal structure and electronic properties of the new iron selenide Ba{sub 9}Fe{sub 4}Se{sub 16}

    Energy Technology Data Exchange (ETDEWEB)

    Berthebaud, David, E-mail: david.berthebaud@ensicaen.fr; Preethi Meher, K.R.S.; Pelloquin, Denis; Maignan, Antoine

    2014-03-15

    The new ternary selenide Ba{sub 9}Fe{sub 4}Se{sub 16} has been synthesized from the reaction of appropriate amounts of elements at high temperature in a silica sealed tube. The compound crystallizes in the tetragonal space group I4{sub 1}/a with a=10.0068(3) Å and c=35.6415(9) Å, Z=4. It is an isostructural compound to the sulfide α-Ba{sub 9}Fe{sub 4}S{sub 15}, which is a high temperature polymorph of β-Ba{sub 9}Fe{sub 4}Se{sub 15} that belongs to the indefinitely adaptive phases series Ba{sub 3}Fe{sub 1+x}S{sub 5}, 0≤x≤1. X-ray powder diffraction and TEM analyses of the synthesized compound were used to determine the phase composition and the structure. The crystal structure can be viewed as overlapping sections along the c axis. Those sections are formed by the coordination polyhedra around barium atoms which can be described as trigonal prisms and bidisphenoids. Within the sections formed by barium polyhedra, isolated pairs of edge sharing FeSe{sub 4} tetrahedra are found. Magnetic measurements performed on Ba{sub 9}Fe{sub 4}Se{sub 16} indicate an antiferromagnetic behavior with Néel temperature of ∼13 K. Possible influence of air exposure on the magnetic properties is also discussed here. The electric measurements show an insulating behavior below 160 K and the dielectric permittivity and loss tangent at the lowest frequency measured reveal a change of slope very close to T{sub N}. However no magneto dielectric effect was evidenced for magnetic fields of up to 3 T. Activation energy, E{sub A}=0.18 eV, was extracted from the AC conductivity plot in the temperature range of 160–300 K. -- Graphical abstract: Experimental electron diffraction (ED) patterns of Ba{sub 9}Fe{sub 4}Se{sub 16} recorded along a-[010]. Highlights: • A new iron selenide material. • A structure resolution by combination of XRD and TEM. • Magnetic properties of the new compound Ba{sub 9}Fe{sub 4}Se{sub 16} are discussed.

  12. Super-resolution readout property of bismuth-doped antimony-based thin film as a functional mask for read-only memory

    Science.gov (United States)

    Lu, Xinmiao; Wu, Yiqun; Wang, Yang; Wei, Jingsong

    2012-09-01

    Bismuth-doped antimony-based (Sb100- x Bi x , x=2.46) thin films were presented as a functional mask for super-resolution readout of read-only memory (ROM). The pit size of the ROM was 390 nm, and super-resolution readout was realized on a dynamic tester with laser wavelength of 780 nm and the numerical aperture of the focusing objective lens of 0.45. The carrier-to-noise ratio (CNR) of 22 dB, readout threshold power of 0.8 mW and super-resolution readout cycles of 2×104 was achieved. The influence of film thickness and readout power on CNR was investigated. The reflectivity and transmittance of the film with different temperature at wavelength of 780 nm were detected, and the super-resolution mechanism of the bismuth-doped antimony-based thin films as the functional mask layer was discussed.

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

    Science.gov (United States)

    Hong, Seung Sae; Cha, Judy J.; Kong, Desheng; Cui, Yi

    2012-03-01

    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 2×1011 cm-2. The zinc oxide-capped, antimony-doped Bi2Se3 nanostructures provide an attractive materials platform to study fundamental physics in topological insulators, as well as future applications.

  14. Antimoniais empregados no tratamento da leishmaniose: estado da arte Antimonials employed in the treatment of leishmaniaisis: the state of the art

    OpenAIRE

    Susanne Rath; Luciano Augusto Trivelin; Talitha Rebecca Imbrunito; Daniela Maria Tomazela; Marcelo Nunes de Jesús; Percy Calvo Marzal; Heitor Franco de Andrade Junior; André Gustavo Tempone

    2003-01-01

    Antimony preparations are the drugs of choice for the treatment of leishmaniasis over 90 years, a disease that currently affects 12 million people worldwide. Its introduction was based on 19th century concepts of therapeutic effects of metal salts as arsenicals and other metals, most of them abandoned due to toxic effects or better drugs. In the last three decades, there was a great improvement in the knowledge of cell biology and immunology of those infections, but chemotherapy has not been ...

  15. Decreased antimony uptake and overexpression of genes of thiol metabolism are associated with drug resistance in a canine isolate of Leishmania infantum

    OpenAIRE

    Verónica Gómez Pérez; Raquel García-Hernandez; Victoriano Corpas-López; Tomás, Ana M.; Joaquina Martín-Sanchez; Santiago Castanys; Francisco Gamarro

    2016-01-01

    Visceral leishmaniasis (VL) caused by the protozoan parasite Leishmania infantum, is one of the most important zoonotic diseases affecting dogs and humans in the Mediterranean area. The presence of infected dogs as the main reservoir host of L. infantum is regarded as the most significant risk for potential human infection. We have studied the susceptibility profile to antimony and other anti-leishmania drugs (amphotericin B, miltefosine, paromomycin) in Leishmania infantum isolates extracted...

  16. Arsenic and antimony determination in refined and unrefined table salts by means of hydride generation atomic absorption spectrometry--comparison of sample decomposition and determination methods

    OpenAIRE

    AKSUNER, Nur; TİRTOM, Vedia Nüket; HENDEN, Emür

    2011-01-01

    An evaluation was made of different digestion methods for the determination of arsenic and antimony in table salt samples prior to hydride generation atomic absorption spectrometric analysis. Microwave acid digestion, classical wet digestion, dry ashing, and fusion were applied to the decomposition of salt samples and optimum conditions were investigated. Samples were decomposed by changing heating time, digestion techniques, and the amount and composition of acid, and then the concen...

  17. Antimony determination in seawater and pore water of marine sediments by means of coprecipitation with Mg(OH)2 and atomic absorption spectrometry

    International Nuclear Information System (INIS)

    The study of biogeochemical cycling of trace elements in inshore marine environment is of basic importance in order to understand the long-term distribution of both conventional and radioactive pollutants among the ecosystem components. Antimony is of radio- ecological interest, and its determination in some environmental matrices (seawater, pore water, biota) is always difficult from the analytical point of view. A quick method for antimony determination in seawater and interstitial water of marine sediments, by coprecipitation with Mg(OH)2 and subsequent atomic absorption measurement, is reported. Coprecipitation recovery (about 80% in optimal conditions) was evaluated using both radiotracers and the addition of known amounts of stable element, and turned out to depend on several parameters (percentage of precipitated Mg as compared to the natural content in seawater, ageing of Mg(OH)2, concomitant Fe and Mn concentrations, etc.). The total standard deviation of the proposed method is about 10%. The variance analysis showed that about 90% of total variance is due to the preconcentration procedure (sample handling and random contaminations) and only about 10% is due to the instrumental measurement. The results of antimony determinations in seawater and pore water of marine sediments collected at Montalto di Castro (Central Mediterranean Sea) are presented and discussed

  18. 原子荧光光谱法测定环境空气中锑%Antimony Determination by Atomic Fluorescence Spectrometry

    Institute of Scientific and Technical Information of China (English)

    顾志勇

    2014-01-01

    采用过氯乙烯滤膜采集环境空气中锑,盐酸-氢氟酸混酸体系微波消解滤膜,原子荧光光谱法测定锑。方法前处理操作过程简单、省时、酸用量少、环境污染小,方法的灵敏度和准确度都有很大的提高。采样体积为300L时,空气中锑的最低检出质量浓度为0.002mg/m3。%Antimony in air was sampled using perchloroethylene filter.The filter was dipped into hydrochloric acid and hydrofluoric acid system and digested by microwave.Atomic fluorescence spectrometry was used to detect anti-mony after.This process is simple and time-saving with easy pretreatment,less amount of acid,and less negative impacts on environment.In addition,the accuracy and precision of the process is better than previous methods. The detection limit of antimony in air is 0.002mg/m3 when the volume of air sample is 300 liters when this process was applied.

  19. Analysis of arsenic and antimony distribution within plants growing at an old mine site in Ouche (Cantal, France) and identification of species suitable for site revegetation.

    Science.gov (United States)

    Jana, Ulrike; Chassany, Vincent; Bertrand, Georges; Castrec-Rouelle, Maryse; Aubry, Emmanuel; Boudsocq, Simon; Laffray, Daniel; Repellin, Anne

    2012-11-15

    One of the objectives of this study was to assess the contamination levels in the tailings of an old antimony mine site located in Ouche (Cantal, France). Throughout the 1.3 ha site, homogenous concentrations of antimony and arsenic, a by-product of the operation, were found along 0-0.5 m-deep profiles. Maximum concentrations for antimony and arsenic were 5780 mg kg(-1) dry tailings and 852 mg kg(-1) dry tailings, respectively. Despite the presence of the contaminants and the low pH and organic matter contents of the tailings, several patches of vegetation were found. Botanical identification determined 12 different genera/species. The largest and most abundant plants were adult pines (Pinus sylvestris), birches (Betula pendula) and the bulrush (Juncus effusus). The distribution of the metalloids within specimens of each genera/species was analysed in order to deduce their concentration and translocation capacities. This was the second goal of this work. All plant specimens were highly contaminated with both metalloids. Most were root accumulators with root to shoot translocation factors Plantago major, and Deschampsia flexuosa. PMID:22789654

  20. High frequency of skin reactions in patients with leishmaniasis treated with meglumine antimoniate contaminated with heavy metals: a comparative approach using historical controls

    Directory of Open Access Journals (Sweden)

    Romero Gustavo Adolfo Sierra

    2003-01-01

    Full Text Available We analyzed data from historical controls treated with meglumine antimoniate to compare the frequency of adverse events observed in patients with cutaneous leishmaniasis treated with the same dose of meglumine antimoniate contaminated with heavy metals in an endemic area of the State of Bahia, Brazil. Group A patients were treated in 2000 with the drug produced by Eurofarma Laboratórios Ltda., São Paulo, Brazil (lot A and group B patients were treated in 1996 with the reference drug produced by Rhodia Farma Ltda., São Paulo, Brazil (lot B. We observed an unusual higher frequency of skin reactions in group A patients. However, all type of adverse events observed in group A were also observed in group B. The physico-chemical analysis of these lots revealed that lot A had lower pH and higher concentration of total and trivalent antimony, lead, cadmium, and arsenic. Our findings suggest that the skin reactions could be attributed to heavy metal contamination of lot A.

  1. High frequency of skin reactions in patients with leishmaniasis treated with meglumine antimoniate contaminated with heavy metals: a comparative approach using historical controls.

    Science.gov (United States)

    Romero, Gustavo Adolfo Sierra; Flores M, Rico Marlon de Moraes; Noronha, Elza Ferreira; Macêdo, Vanize de Oliveira

    2003-01-01

    We analyzed data from historical controls treated with meglumine antimoniate to compare the frequency of adverse events observed in patients with cutaneous leishmaniasis treated with the same dose of meglumine antimoniate contaminated with heavy metals in an endemic area of the State of Bahia, Brazil. Group A patients were treated in 2000 with the drug produced by Eurofarma Laborat rios Ltda., S o Paulo, Brazil (lot A) and group B patients were treated in 1996 with the reference drug produced by Rhodia Farma Ltda., S o Paulo, Brazil (lot B). We observed an unusual higher frequency of skin reactions in group A patients. However, all type of adverse events observed in group A were also observed in group B. The physico-chemical analysis of these lots revealed that lot A had lower pH and higher concentration of total and trivalent antimony, lead, cadmium, and arsenic. Our findings suggest that the skin reactions could be attributed to heavy metal contamination of lot A.

  2. A green analytical procedure for sensitive and selective determination of antimony in environmental and biological samples by ligandless cloud point extraction

    Science.gov (United States)

    Rezaei, Vida; Samadi-Maybodi, Abdolraouf

    2012-09-01

    A very simple, environmental friendly and sensitive method based on the cloud point extraction (CPE) separation and spectrophotometric detection has been developed for the determination of antimony. The method is founded on the color reaction of Sb (III) with iodide in acidic medium and subsequent micelle-mediated extraction of the product using the non-ionic surfactant, Triton X-114, in the absence of any chelating agent. The Effects of reaction and extraction parameters were studied and optimum conditions were established. The calibration graph was linear in the range of 0.80-95 ng mL-1 of antimony in the initial solution with r = 0.9994 (n = 9). Detection limit based on three times the standard deviation of the blank (3Sb) was 0.23 ng mL-1 and the relative standard deviation (R.S.D.) for 10 and 70 ng mL-1 of antimony were 3.32 and 1.85% (n = 8), respectively. The proposed method was compared with other methods and favorably applied to evaluate this metal in some real samples, including seawater, antileishmanial drug (glucantime) and human serum.

  3. 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).

  4. Flame-retardancy of a Cellulosic Fabric by the Application of Synergistic Effect between Ammonium Bromide and Antimony (Ⅲ)Oxide

    Institute of Scientific and Technical Information of China (English)

    MOSTASHARI Seyed Morteza; MOAFI Hadi Fallah

    2009-01-01

    The synergistic effect between ammonium bromide and antimony(Ⅲ) oxide as a nondurable finish on the flammability of 100% woven plain cotton fabric(with a density of 144 g/m2,the number of yarns 21 per 10 mm),has been investigated in this study. The laundered totally-dried, weighed specimens were impregnated with suitable concentration individual aqueous ammonium bromide and/or antimony (Ⅲ)oxide suspension solutions and some sets weIle impregnated with appropriate admixed solutions of the both chemicals.A vertical flame spread test Was then carried-out to characterize the flammability of the samples.An acceptable synergistic effect was then experi.enced by using an admixed bath containing 0.1 molar ammonium bromide and O.05 unit formal antimony trioxide solutions for impartation of flame.retardancy to a cotton fabric.The optimum mass of the mixture required to lm.Dart flame-retardancy was about 3.64 g of anhydrous additives per 100 g of fabric.The results obtained are in favor 0f Wall Effect Theory.Moreover synergistic eflfect indicating dehydration of the treated substrate by using this combination via thermogravimetry could be deduced.

  5. Electronic characterization of defects in narrow gap semiconductors: Comparison of electronic energy levels and formation energies in mercury cadmium telluride, mercury zinc telluride, and mercury zinc selenide

    Science.gov (United States)

    Patterson, James D.; Li, Wei-Gang

    1995-01-01

    The project has evolved to that of using Green's functions to predict properties of deep defects in narrow gap materials. Deep defects are now defined as originating from short range potentials and are often located near the middle of the energy gap. They are important because they affect the lifetime of charge carriers and hence the switching time of transistors. We are now moving into the arena of predicting formation energies of deep defects. This will also allow us to make predictions about the relative concentrations of the defects that could be expected at a given temperature. The narrow gap materials mercury cadmium telluride (MCT), mercury zinc telluride (MZT), and mercury zinc selenide (MZS) are of interest to NASA because they have commercial value for infrared detecting materials, and because there is a good possibility that they can be grown better in a microgravity environment. The uniform growth of these crystals on earth is difficult because of convection (caused by solute depletion just ahead of the growing interface, and also due to thermal gradients). In general it is very difficult to grow crystals with both radial and axial homogeneity.

  6. Synthesis, crystal structure, and magnetic properties of quaternary iron selenides: Ba2FePnSe5 (Pn=Sb, Bi)

    Science.gov (United States)

    Wang, Jian; Greenfield, Joshua T.; Kovnir, Kirill

    2016-10-01

    Two new barium iron pnictide-selenides, Ba2FeSbSe5 and Ba2FeBiSe5, were synthesized by a high-temperature solid-state route and their crystal structures were determined using single crystal X-ray diffraction. Both compounds are isomorphic to the high pressure phase Ba3FeS5 and crystallize in the orthorhombic space group Pnma (No. 62) with cell parameters of a=12.603(2)/12.619(2) Å, b=9.106(1)/9.183(1) Å, c=9.145(1)/9.123(1) Å and Z=4 for Ba2FeSbSe5 and Ba2FeBiSe5, respectively. According to differential scanning calorimetry, Ba2FePnSe5 compounds exhibit high thermal stability and melt congruently at 1055(5) K (Pn=Sb) and 1105(5) K (Pn=Bi). Magnetic characterizations reveal strong antiferromagnetic nearest-neighbor interactions in both compounds resulting in an antiferromagnetic ordering at 58(1) K for Ba2FeSbSe5 and 79(2) K for Ba2FeBiSe5. The magnetic interactions between Fe3+ centers, which are at least 6 Å apart from each other, are mediated by superexchange interactions.

  7. Quantitative study of the effect of deposition temperature on antimony incorporation in InAs/InAsSb superlattices

    Science.gov (United States)

    Haugan, H. J.; Mahalingam, K.; Szmulowicz, F.; Brown, G. J.

    2016-02-01

    InAs/InAsSb superlattices (SLs) are being actively explored for infrared detector applications owing to their superior carrier lifetimes. However, antimony (Sb) segregation during growth can alter the properties of the grown material. In this study, using X-ray energy dispersive spectrometry, authors quantify the compositional profile of individual layers and establish epitaxial parameters for high-quality InAs/InAsSb SL materials. Epitaxial conditions are determined for a nominal 7.7 nm InAs/3.5 nm InAs0.7Sb0.3 SL structure tailored for an approximately 6 μm response at 150 K. Since the growth of mixed anion alloys is complicated by the potential reaction of As2 with Sb surfaces, authors varied the deposition temperature (Tg) in order to control As2 surface reactions on Sb surfaces. Authors find that Sb incorporation is suppressed by 21%, with the increase of Tg from 395 to 440 °C. This incorporation likely stems from Sb surface segregation during InAsSb layer growth that is driven by the As-Sb exchange mechanism, which can lead to significant compositional and dimensional deviations from the intended design.

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

    Science.gov (United States)

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

    2016-11-15

    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 30days. 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.

  9. Lithium intercalation in sputter deposited antimony-doped tin oxide thin films: Evidence from electrochemical and optical measurements

    Energy Technology Data Exchange (ETDEWEB)

    Montero, J., E-mail: jose.montero@angstrom.uu.se; Granqvist, C. G.; Niklasson, G. A. [Department of Engineering Sciences, The A°ngström Laboratory, Uppsala University, P.O. Box 534, SE-751 21 Uppsala (Sweden); Guillén, C.; Herrero, J. [Department of Energy, Ciemat, Avda. Complutense 40, Ed. 42, E-28040 Madrid (Spain)

    2014-04-21

    Transparent conducting oxides are used as transparent electrical contacts in a variety of applications, including in electrochromic smart windows. In the present work, we performed a study of transparent conducting antimony-doped tin oxide (ATO) thin films by chronopotentiometry in a Li{sup +}-containing electrolyte. The open circuit potential vs. Li was used to investigate ATO band lineups, such as those of the Fermi level and the ionization potential, as well as the dependence of these lineups on the preparation conditions for ATO. Evidence was found for Li{sup +} intercalation when a current pulse was set in a way so as to drive ions from the electrolyte into the ATO lattice. Galvanostatic intermittent titration was then applied to determine the lithium diffusion coefficient within the ATO lattice. The electrochemical density of states of the conducting oxide was studied by means of the transient voltage recorded during the chronopotentiometry experiments. These measurements were possible because, as Li{sup +} intercalation took place, charge compensating electrons filled the lowest part of the conduction band in ATO. Furthermore, the charge insertion modified the optical properties of ATO according to the Drude model.

  10. Antimony segregation in Ge and formation of n-type selectively doped Ge films in molecular beam epitaxy

    International Nuclear Information System (INIS)

    Antimony segregation in Ge(001) films grown by molecular beam epitaxy was studied. A quantitative dependence of the Sb segregation ratio in Ge on growth temperature was revealed experimentally and modeled theoretically taking into account both the terrace-mediated and step-edge-mediated segregation mechanisms. A nearly 5-orders-of-magnitude increase in the Sb segregation ratio in a relatively small temperature range of 180–350 °C was obtained, which allowed to form Ge:Sb doped layers with abrupt boundaries and high crystalline quality using the temperature switching method that was proposed earlier for Si-based structures. This technique was employed for fabrication of different kinds of n-type Ge structures which can be useful for practical applications like heavily doped n+-Ge films or δ-doped layers. Estimation of the doping profiles sharpness yielded the values of 2–5 nm per decade for the concentration gradient at the leading edge and 2–3 nm for the full-width-half-maximum of the Ge:Sb δ-layers. Electrical characterization of grown Ge:Sb structures revealed nearly full electrical activation of Sb atoms and the two-dimensional nature of charge carrier transport in δ-layers

  11. Photocurrent Generation by Photosynthetic Purple Bacterial Reaction Centers Interfaced with a Porous Antimony-Doped Tin Oxide (ATO) Electrode.

    Science.gov (United States)

    Carey, Anne-Marie; Zhang, HaoJie; Mieritz, Daniel; Volosin, Alex; Gardiner, Alastair T; Cogdell, Richard J; Yan, Hao; Seo, Dong-Kyun; Lin, Su; Woodbury, Neal W

    2016-09-28

    The ability to exchange energy and information between biological and electronic materials is critical in the development of hybrid electronic systems in biomedicine, environmental sensing, and energy applications. While sensor technology has been extensively developed to collect detailed molecular information, less work has been done on systems that can specifically modulate the chemistry of the environment with temporal and spatial control. The bacterial photosynthetic reaction center represents an ideal photonic component of such a system in that it is capable of modifying local chemistry via light-driven redox reactions with quantitative control over reaction rates and has inherent spectroscopic probes for monitoring function. Here a well-characterized model system is presented, consisting of a transparent, porous electrode (antimony-doped tin oxide) which is electrochemically coupled to the reaction center via a cytochrome c molecule. Upon illumination, the reaction center performs the 2-step, 2-electron reduction of a ubiquinone derivative which exchanges with oxidized quinone in solution. Electrons from the electrode then move through the cytochrome to reoxidize the reaction center electron donor. The result is a facile platform for performing redox chemistry that can be optically and electronically controlled in time and space.

  12. 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. PMID:26652385

  13. A green synthesis route for the phase and size tunability of copper antimony sulfide nanocrystals with high yield.

    Science.gov (United States)

    Chen, Keqiang; Zhou, Jing; Chen, Wen; Chen, Qiao; Zhou, Peng; Liu, Yueli

    2016-03-01

    Until now, it is a great challenge for the controllable synthesis of copper antimony sulfide (CAS) nanocrystals (NCs), as the reactivity of precursors is quite difficult to be controlled during the synthesis process. In the present work, a novel solution-based method is proposed to synthesize CAS NCs by choosing N,N'-diphenylthiourea as the sulfide precursor, which is favorable for balancing the relative reactivity of Cu and Sb ions. It is found that three phases (CuSbS2, Cu12Sb4S13 and Cu3SbS4) of CAS NCs with size tunability were successfully synthesized for the first time. To the best of our knowledge, the lowest reaction temperature of 110 °C and the highest yield over 90% for CAS NCs were also achieved for the first time, which may be considered to be a green synthesis route compared with other conventional methods. Optical properties indicate that the as-prepared CAS NCs have strong optical absorption in the visible light region of the solar spectrum, and we also observed the band gap tunability of CuSbS2 and Cu3SbS4 materials for the first time. PMID:26875832

  14. 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.

  15. Arsenic and antimony in water and wastewater: overview of removal techniques with special reference to latest advances in adsorption.

    Science.gov (United States)

    Ungureanu, Gabriela; Santos, Sílvia; Boaventura, Rui; Botelho, Cidália

    2015-03-15

    Arsenic and antimony are metalloids, naturally present in the environment but also introduced by human activities. Both elements are toxic and carcinogenic, and their removal from water is of unquestionable importance. The present article begins with an overview of As and Sb chemistry, distribution and toxicity, which are relevant aspects to understand and develop remediation techniques. A brief review of the recent results in analytical methods for speciation and quantification was also provided. The most common As and Sb removal techniques (coagulation/flocculation, oxidation, membrane processes, electrochemical methods and phyto and bioremediation) are presented with discussion of their advantages, drawbacks and the main recent achievements. Literature review on adsorption and biosorption were focused in detail. Considering especially the case of developing countries or rural communities, but also the finite energy resources that over the world are still dependent, recent research have focused especially readily available low-cost adsorbents, as minerals, wastes and biosorbents. Many of these alternative sorbents have been presenting promising results and can be even superior when compared to the commercial ones. Sorption capacities were accurately compiled for As(III,V) and Sb(III,V) species in order to provide to the reader an easy but detailed comparison. Some aspects related to experimental conditions, comparison criteria, lack of research studies, economic aspects and adsorption mechanisms were critically discussed. PMID:25585146

  16. Quadrupole coupling constants and isomeric Moessbauer shifts for halogen-containing gold, platinum, niobium, tantalum and antimony compounds

    International Nuclear Information System (INIS)

    We have analyzed by means of Density functional theory calculations the nuclear quadrupole coupling constants of a range of gold, antimony, platinum, niobium and tantalum compounds. The geometrical parameters and halogen nuclear quadrupole coupling constants obtained by these calculations substantially corresponded to the data of microwave and nuclear quadrupole resonance spectroscopy. An analysis of the quality of the calculations that employ pseudo-potentials and all-electron basis sets for the halogen compounds was carried out. The zero order regular approximation (ZORA) method is shown to be a viable alternative for the calculation of halogen coupling constants in molecules. In addition, the ZORA model, in contrast to the pseudo-potential model, leads to realistic values of all metal nuclear quadrupole coupling constants. From Klopman's approach, it follows that the relationship between the electrostatic bonding and covalent depends on the nature of the central atom. The results on Moessbauer chemical shifts are also in a good agreement with the coordination number of the central atom.

  17. Use of cloud-point preconcentration for spectrophotometric determination of trace amounts of antimony in biological and environmental samples.

    Science.gov (United States)

    El-Sharjawy, Abdel-Azeem M; Amin, Alaa S

    2016-01-01

    This work presents a cloud-point extraction process using the micelle-mediated extraction method for simultaneous preconcentration and determination of Sb(III) and Sb(V) species in biological and environmental samples as a prior preconcentration step to their spectrophotometric determination. The analytical system is based on the selective reaction between Sb(III) and 3-dichloro-6-(3-carboxy-2-hydroxy-1-naphthylazo)quinoxaline (DCHNAQ) in the presence of cetyltrimethylammonium bromide (CTAB) and potassium iodide at pH 4.5. Total Sb concentration was determined after reduction of Sb(V) to Sb(III) in the presence of potassium iodide and ascorbic acid. The optimal reaction conditions and extraction were studied, and the analytical characteristics of the method (e.g., limits of detection and quantification, linear range, preconcentration, improvement factors) were obtained. Linearity for Sb(III) was obeyed in the range of 0.2-20 ng ml(-1). The detection and quantification limits for the determination of Sb(III) were 0.055 and 0.185 ng ml(-1), respectively. The method has a lower detection limit and wider linear range, inexpensive instrument, and low cost, and is more sensitive compared with most other methods. The interference effect of some anions and cations was also studied. The method was applied to the determination of Sb(III) in the presence of Sb(V) and total antimony in blood plasma, urine, biological, and water samples.

  18. Profiling microbial community in a watershed heavily contaminated by an active antimony (Sb) mine in Southwest China.

    Science.gov (United States)

    Sun, Weimin; Xiao, Enzong; Dong, Yiran; Tang, Song; Krumins, Valdis; Ning, Zengping; Sun, Min; Zhao, Yanlong; Wu, Shiliang; Xiao, Tangfu

    2016-04-15

    Located in Southwest China, the Chahe watershed has been severely contaminated by upstream active antimony (Sb) mines. The extremely high concentrations of Sb make the Chahe watershed an excellent model to elucidate the response of indigenous microbial activities within a severe Sb-contaminated environment. In this study, water and surface sediments from six locations in the Chahe watershed with different levels of Sb contamination were analyzed. Illumina sequencing of 16S rRNA amplicons revealed more than 40 phyla from the domain Bacteria and 2 phyla from the domain Archaea. Sequences assigned to the genera Flavobacterium, Sulfuricurvum, Halomonas, Shewanella, Lactobacillus, Acinetobacter, and Geobacter demonstrated high relative abundances in all sequencing libraries. Spearman's rank correlations indicated that a number of microbial phylotypes were positively correlated with different speciation of Sb, suggesting potential roles of these phylotypes in microbial Sb cycling. Canonical correspondence analysis further demonstrated that geochemical parameters, including water temperature, pH, total Fe, sulfate, aqueous Sb, and Eh, significantly structured the overall microbial community in Chahe watershed samples. Our findings offer a direct and reliable reference to the diversity of microbial communities in the presence of extremely high Sb concentrations, and may have potential implications for in situ bioremediation strategies of Sb contaminated sites. PMID:26820933

  19. Low Temperature Calorimetric Investigation of the Spin Glasses: MERCURY(1-X)MANGANESE(X)TELLURIDE and COBALT(X)GALLIUM(1-X); and of the Compounds: Mercury-Telluride Alpha - Mercury Sulfide, Beta - Mercury Sulfide, THALLIUM(3)ARSENIC SELENIDE(3), THALLIUM(3)ANTIMONY SULFIDE(3), Silver-Thallium - and Silver-Thallium

    Science.gov (United States)

    Akbarzadeh, Hadi

    A systematic study of the low-dc-field magnetic susceptibility and the specific heat has been carried out on mixes Hg(,1-x)Mn(,x)Te crystals, in the composition range 0 (LESSTHEQ) x (LESSTHEQ) 0.35. The alloy with x = 0.35 showed spin-glass behavior below T = 10.9 K. The observed spin-glass phase is ascribed to the frustration of the antiferromagnetic interactions. For x (LESSTHEQ) 0.25, the Hg(,1-x)Mn(,x)Te samples remain paramagnetic down to 1 K. Experimental results for the specific heat and the susceptibility for x 0.52 it also has contributions by the cobalt nuclei, proportional to T('-2), and a spin wave contribution proportional to T('3/2). This last term indicates the coexistence of spin glass and ferromagnetic properties. A simple two level system model fits the spin glass specific heat very well. The agreement between experimental and calculated specific heat shows that individual AS defects are responsible for the thermal properties. To explain hysteresis and remanence objects containing thousands of AS defects have been proposed. On increasing the temperature some objects become unfrozen. We speculate that the individual AS defects in the unfrozen objects can adjust themselves over their own two levels and so contribute to the thermal properties. Specific heats of mercury chalcogenides (HgTe, HgSe, (alpha)-HgS, (beta)-HgS) and red HgI(,2) have been measured in the temperature range of 0.4 - 50 K. All materials display well defined maxima in CT('-3) which indicate the presence of low-lying modes described by Einstein oscillators. The specific heats of Tl(,3)AsSe, Tl(,3)SbS(,3), AgTlS, and AgTlSe have been measured between 1 and 50 K. The Debye temperatures are, respectively: 140, 145, 160, 140 K. Above 2.5 K an additional contribution is noticed which indicates low-lying optical modes.

  20. Crystal and electronic structures of two new iron selenides: Ba{sub 4}Fe{sub 3}Se{sub 10} and BaFe{sub 2}Se{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Berthebaud, David, E-mail: david.berthebaud@ensicaen.fr [CNRS CRISMAT UMR6508, 6 Boulevard du Maréchal Juin, F-14050 CAEN Cedex 4 (France); Perez, Olivier [CNRS CRISMAT UMR6508, 6 Boulevard du Maréchal Juin, F-14050 CAEN Cedex 4 (France); Tobola, Janusz [Faculty of Physics and Applied Computer Science, AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Krakow (Poland); Pelloquin, Denis; Maignan, Antoine [CNRS CRISMAT UMR6508, 6 Boulevard du Maréchal Juin, F-14050 CAEN Cedex 4 (France)

    2015-10-15

    The new ternary selenides, Ba{sub 4}Fe{sub 3}Se{sub 10} and BaFe{sub 2}Se{sub 4,} were synthesized from a reaction of appropriate amounts of elements at high temperature in a silica sealed tube, and their structures were resolved using X-ray single crystal diffraction. BaFe{sub 2}Se{sub 4} crystallizes in the tetragonal space group I4/m with a=8.008(9) Å and c=5.483(3) Å as cell parameters. It is a new compound with a structure isotypical to the sulfide BaFe{sub 2}S{sub 4} which belongs to the infinitely adaptive structures series Ba{sub 1+x}Fe{sub 2}S{sub 4}. The second compound, Ba{sub 4}Fe{sub 3}Se{sub 10}, crystallizes in the monoclinic space group P2{sub 1}/n with a=8.8593(1) Å, b=8.8073(1) Å, c=12.2724(1) Å and β=109.037(6)° as cell parameters. It exhibits an original structure with a new type of iron selenide polyhedra. These data were consistent with the powder X-ray diffraction and TEM analyses. Their electronic structures point towards metallicity and electronic correlations for both selenides. - Graphical abstract: Experimental [010] oriented ED pattern and corresponding HREM image of Ba{sub 4}Fe{sub 3}Se{sub 10}. Image calculated with a focus and thickness to 15nm and 8 nm respectively is inserted. Bright contrasts are correlated to Se rows belonging to FeSe{sub 3}(Se{sub 2}){sup 2−}–FeSe{sub 6}–FeSe{sub 3}(Se{sub 2}){sup 2−} trimers. The corresponding structure projection is also shown. - Highlights: • Two new barium iron selenide compounds. • An original structure type Ba4Fe3Se10. • Electronic structure calculations.

  1. Influence of the substrate temperature on the structural, optical, and electrical properties of tin selenide thin films deposited by thermal evaporation method

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, N.; Sharma, V.; Padha, N. [Department of Physics and Electronics, Dr. Ambedkar Road, University of Jammu, Jammu-180 006, Jammu and Kashmir State (India); Shah, N.M.; Desai, M.S.; Panchal, C.J. [Applied Physics Department, Faculty of Technology and Engineering, M. S. University of Baroda, Vadodara-390 001, Gujarat State (India); Protsenko, I.Yu. [Appl. Physics Dept., Faculty of Electronic and Information Technologies, Sumy State University (Ukraine)

    2010-01-15

    Thin films of tin selenide (SnSe) were deposited on sodalime glass substrates, which were held at different temperatures in the range of 350-550 K, from the pulverized compound material using thermal evaporation method. The effect of substrate temperature (T{sub s}) on the structural, morphological, optical, and electrical properties of the films were investigated using x-ray diffraction analysis (XRD), scanning electron microscopy (SEM), transmission measurements, and Hall-effect characterization techniques. The temperature dependence of the resistance of the films was also studied in the temperature range of 80-330 K. The XRD spectra and the SEM image analyses suggest that the polycrystalline thin films having uniform distribution of grains along the (111) diffraction plane was obtained at all T{sub s}. With the increase of T{sub s} the intensity of the diffraction peaks increased and well-resolved peaks at 550 K, substrate temperature, were obtained. The analysis of the data of the optical transmission spectra suggests that the films had energy band gap in the range of 1.38-1.18 eV. Hall-effect measurements revealed the resistivity of films in the range 112-20 {omega} cm for films deposited at different T{sub s}. The activation energy for films deposited at different T{sub s} was in the range of 0.14 eV-0.28 eV as derived from the analysis of the data of low-temperature resistivity measurements. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  2. Electronic Characterization of Defects in Narrow Gap Semiconductors-Comparison of Electronic Energy Levels and Formation Energies in Mercury Cadmium Telluride, Mercury Zinc Telluride, and Mercury Zinc Selenide

    Science.gov (United States)

    Patterson, James D.

    1996-01-01

    We have used a Green's function technique to calculate the energy levels and formation energy of deep defects in the narrow gap semiconductors mercury cadmium telluride (MCT), mercury zinc telluride (MZT) and mercury zinc selenide (MZS). The formation energy is calculated from the difference between the total energy with an impurity cluster and the total energy for the perfect crystal. Substitutional (including antisite), interstitial (self and foreign), and vacancy deep defects are considered. Relaxation effects are calculated (with molecular dynamics). By use of a pseudopotential, we generalize the ideal vacancy model so as to be able to consider relaxation for vacancies. Different charge states are considered and the charged state energy shift (as computed by a modified Haldane-Anderson model) can be twice that due to relaxation. Different charged states for vacancies were not calculated to have much effect on the formation energy. For all cases we find deep defects in the energy gap only for cation site s-like orbitals or anion site p-like orbitals, and for the substitutional case only the latter are appreciably effected by relaxation. For most cases for MCT, MZT, MZS, we consider x (the concentration of Cd or Zn) in the range appropriate for a band gap of 0.1 eV. For defect energy levels, the absolute accuracy of our results is limited, but the precision is good, and hence chemical trends are accurately predicted. For the same reason, defect formation energies are more accurately predicted than energy level position. We attempt, in Appendix B, to calculate vacancy formation energies using relatively simple chemical bonding ideas due to Harrison. However, these results are only marginally accurate for estimating vacancy binding energies. Appendix C lists all written reports and publications produced for the grant. We include abstracts and a complete paper that summarizes our work which is not yet available.

  3. The presence of mercury selenide in various tissues of the striped dolphin: evidence from μ-XRF-XRD and XAFS analyses.

    Science.gov (United States)

    Nakazawa, Emiko; Ikemoto, Tokutaka; Hokura, Akiko; Terada, Yasuko; Kunito, Takashi; Tanabe, Shinsuke; Nakai, Izumi

    2011-07-01

    Marine mammals accumulate mercury in their tissues at high concentration and detoxify by forming mercury selenide (HgSe, tiemannite) mainly in the liver. We investigated the possibility of formation of HgSe in various tissues (liver, kidney, lung, spleen, pancreas, muscle and brain) other than the liver of the striped dolphin (Stenella coeruleoalba). We applied a combination method of micro-X-ray fluorescence (μ-XRF) imaging and micro-X-ray diffraction (μ-XRD) using a synchrotron radiation X-ray microbeam to analyze the tissue samples directly with minimal sample preparation. By this method, many accumulation points for Hg and Se on a micron scale were found in thin sections of the spleen and liver tissue and consequently, the XRF spectra and the XRD pattern of the hot spots confirmed the presence of tiemannite, HgSe. On the other hand, the insoluble fractions after enzyme digestion of the nuclear and mitochondrial fractions of all tissues were subjected to X-ray absorption fine structure (XAFS) analysis. XAFS analysis confirmed the presence of HgSe in all the tissues examined (liver, kidney, lung, spleen, pancreas, muscle and brain) of the striped dolphin. The presence of HgSe in all the tissues examined suggests that Se would be involved in the detoxification process of Hg in various tissues other than the liver. This contribution seems to be large especially in the liver and spleen but relatively small in the kidney, pancreas and brain, because the proportion of insoluble fraction containing HgSe was lower in these tissues (25 to 46%). This is the first report on the presence of tiemannite HgSe in various tissues of marine mammals. PMID:21468440

  4. Determination of the some electronic parameters of nanostructure copper selenide and Cu/Cu3Se2/n-GaAs/In structure

    International Nuclear Information System (INIS)

    Highlights: • Introducing to a new degree of freedom in the control of effective barrier height by using Cu. • We want to experimentally observe whether or not the diode continues the ideality in the temperature range of 60–400 K. • We have modified the Richardson’s plot using the temperature dependent values of effective area of the patches. - Abstract: The nanostructure copper selenide thin film has been grown on n-type gallium arsenide substrate by Successive Ionic Layer Adsorption and Reaction (SILAR) method. The film has been characterized by X-ray Diffraction (XRD), Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM) measurements. X-ray diffraction analysis of the film confirms a polycrystalline with preferred orientation. The AFM and SEM micrographs of the film reveal smooth and uniform surface pattern without any dark pits, pinholes and microcracks. The Cu/Cu3Se2/n-GaAs/In structure has been thermally formed in evaporating system after the SILAR process. The electrical analysis of Cu/Cu3Se2/n-GaAs/In structure has been investigated by means of current–voltage (I–V) measurements in the temperature range of 60–400 K in dark conditions. The values of barrier height (BH) and ideality factor (n) ranged from 0.21 eV and 4.97 (60 K) to 0.83 eV and 1.14 (400 K), respectively. In the calculations, the electrical parameters of the experimental forward bias I–V characteristics of the Cu/Cu3Se2/n-GaAs/In with the homogeneity in the 60–400 K range have been explained by means of the thermionic emission (TE), considering Gaussian distribution (GD) of BH with linear bias dependence

  5. Microbial toxicity of ionic species leached from the II-VI semiconductor materials, cadmium telluride (CdTe) and cadmium selenide (CdSe).

    Science.gov (United States)

    Ramos-Ruiz, Adriana; Zeng, Chao; Sierra-Alvarez, Reyes; Teixeira, Luiz H; Field, Jim A

    2016-11-01

    This work investigated the microbial toxicity of soluble species that can potentially be leached from the II-VI semiconductor materials, cadmium telluride and cadmium selenide. The soluble ions tested included: cadmium, selenite, selenate, tellurite, and tellurate. Their toxicity towards the acetoclastic and hydrogen-consuming trophic groups in a methanogenic consortium as well as towards a bioluminescent marine bacterium, Aliivibrio fischeri (Microtox(®) test), was assessed. The acetoclastic methanogenic activity was the most affected as evidenced by the low 50% inhibiting concentrations (IC50) values obtained of 8.6 mg L(-1) for both cadmium and tellurite, 10.2 mg L(-1) for tellurate, and 24.1 mg L(-1) for selenite. Both tellurium oxyanions caused a strong inhibition of acetoclastic methanogenesis at low concentrations, each additional increment in concentration provided progressively less inhibition increase. In the case of the hydrogenotrophic methanogenesis, cadmium followed by selenite caused the greatest inhibition with IC50 values of 2.9 and 18.0 mg L(-1), respectively. Tellurite caused a moderate effect as evidenced by a 36.8% inhibition of the methanogenic activity at the highest concentration tested, and a very mild effect of tellurate was observed. Microtox(®) analyses showed a noteworthy inhibition of cadmium, selenite, and tellurite with 50% loss in bioluminescence after 30 min of exposure of 5.5, 171.1, and 458.6 mg L(-1), respectively. These results suggest that the leaching of cadmium, tellurium and selenium ions from semiconductor materials can potentially cause microbial toxicity.

  6. Microbial toxicity of ionic species leached from the II-VI semiconductor materials, cadmium telluride (CdTe) and cadmium selenide (CdSe).

    Science.gov (United States)

    Ramos-Ruiz, Adriana; Zeng, Chao; Sierra-Alvarez, Reyes; Teixeira, Luiz H; Field, Jim A

    2016-11-01

    This work investigated the microbial toxicity of soluble species that can potentially be leached from the II-VI semiconductor materials, cadmium telluride and cadmium selenide. The soluble ions tested included: cadmium, selenite, selenate, tellurite, and tellurate. Their toxicity towards the acetoclastic and hydrogen-consuming trophic groups in a methanogenic consortium as well as towards a bioluminescent marine bacterium, Aliivibrio fischeri (Microtox(®) test), was assessed. The acetoclastic methanogenic activity was the most affected as evidenced by the low 50% inhibiting concentrations (IC50) values obtained of 8.6 mg L(-1) for both cadmium and tellurite, 10.2 mg L(-1) for tellurate, and 24.1 mg L(-1) for selenite. Both tellurium oxyanions caused a strong inhibition of acetoclastic methanogenesis at low concentrations, each additional increment in concentration provided progressively less inhibition increase. In the case of the hydrogenotrophic methanogenesis, cadmium followed by selenite caused the greatest inhibition with IC50 values of 2.9 and 18.0 mg L(-1), respectively. Tellurite caused a moderate effect as evidenced by a 36.8% inhibition of the methanogenic activity at the highest concentration tested, and a very mild effect of tellurate was observed. Microtox(®) analyses showed a noteworthy inhibition of cadmium, selenite, and tellurite with 50% loss in bioluminescence after 30 min of exposure of 5.5, 171.1, and 458.6 mg L(-1), respectively. These results suggest that the leaching of cadmium, tellurium and selenium ions from semiconductor materials can potentially cause microbial toxicity. PMID:27494313

  7. STUDY ON THE REMOVAL OF ANTIMONY FOR PRODUCING SODIUM STANNATE BY TIN SLAG%锡渣生产锡酸钠中除锑的研究

    Institute of Scientific and Technical Information of China (English)

    卢丹艳

    2012-01-01

    利用生产硫酸亚锡、氯化亚锡、锡:扮的含锡废料生产锡酸钠,生产成本低,但在这过程中需要除去的杂质也相对比较多。文章对除锑的工艺参数和条件进行了研究,重点探讨了除锑温度、除锑时间、除锑后溶液静置沉降时间等因素对锑效果的影响。结果表明,采用该工艺,Sb的脱除率为95.3%,产品质量符合Sn-42等级标准。%waste material that contains tin and can be used for producing Stannous sulfate, Stannous chloride and Tin powder is use for producing Sodium stannate. The cost of production may stay at a relative low level. But It needs to get rid of More impurities, Relatively speaking .In this paper, the process parameters and conditions of the removal of Antimony are studied. The factors such as the temperature and time of the removal of Antimony and time of sedimentation time of the Solution are discussed, which have an influence on the removal of Antimony. It is shown that, using this technology, removal rate of Sb is 95.3%, and the Product quality is In accordance with the grading standard of Sn 42.

  8. Development of a non-chromatographic method for the speciation analysis of inorganic antimony in mushroom samples by hydride generation atomic fluorescence spectrometry

    Science.gov (United States)

    Sousa Ferreira, Hadla; Costa Ferreira, Sergio Luis; Cervera, M. Luisa; de la Guardia, Miguel

    2009-06-01

    A simple and sensitive method has been developed for the direct determination of toxic species of antimony in mushroom samples by hydride generation atomic fluorescence spectrometry (HG AFS). The determination of Sb(III) and Sb(V) was based on the efficiency of hydride generation employing NaBH 4, with and without a previous KI reduction, using proportional equations corresponding to the two different measurement conditions. The extraction efficiency of total antimony and the stability of Sb(III) and Sb(V) in different extraction media (nitric, sulfuric, hydrochloric, acetic acid, methanol and ethanol) were evaluated. Results demonstrated that, based on the extraction yield and the stability of extracts, 0.5 mol L - 1 H 2SO 4 proved to be the best extracting solution for the speciation analysis of antimony in mushroom samples. The limits of detection of the developed methodology were 0.6 and 1.1 ng g - 1 for Sb(III) and Sb(V), respectively. The relative standard derivation was 3.8% (14.7 ng g - 1 ) for Sb(V) and 5.1% (4.6 ng g - 1 ) for Sb(III). The recovery values obtained for Sb(III) and Sb(V) varied from 94 to 106% and from 98 to 105%, respectively. The method has been applied to determine Sb(III), Sb(V) and total Sb in five different mushroom samples; the Sb(III) content varied from 4.6 to 11.4 ng g - 1 and Sb(V) from 14.7 to 21.2 ng g - 1 . The accuracy of the method was confirmed by the analysis of a certified reference material of tomato leaves.

  9. Preparation of Highly Dispersed Antimony-doped Tin Oxide Nano-powder via Ion-exchange Hydrolysis of SnCl4 and SbCl3 and Azeotropic Drying

    Institute of Scientific and Technical Information of China (English)

    YANG Fen; ZHANG Xue-jun; TIAN Fang; WU Xu; GAN Fu-xing

    2007-01-01

    Antimony-doped tin hydroxide colloid precipitates have been synthesized by hydrolysis of SnCl4 and SbCl3 using: (1) an ion-exchange hydrolysis to remove chlorine ions, and (2) isoamyl acetate as an azeotropic solvent to obviate water. The obtained dried powder is of high dispersivity without any need for further grinding. The size and dispersivity of the final particles are investigated with the aid of TG-DTA, BET, XRD and TEM. After having calcined, the antimony-doped tin oxide nanopowder possesses a tetragonal rutile structure with high dispersivity, uniform particles and low hard agglomeration.

  10. Facilitated extracellular electron transfer of Shewanella loihica PV-4 by antimony-doped tin oxide nanoparticles as active microelectrodes

    Science.gov (United States)

    Zhang, Xiaojian; Liu, Huan; Wang, Jinrong; Ren, Guangyuan; Xie, Beizhen; Liu, Hong; Zhu, Ying; Jiang, Lei

    2015-11-01

    Dissimilatory metal reducing bacteria are capable of extracellular electron transfer (EET) to insoluble metal oxides as external electron acceptors for their anaerobic respiration, which is recognized as an important energy-conversion process in natural and engineered environments, such as in mineral cycling, bioremediation, and microbial fuel/electrolysis cells. However, the low EET efficiency remains one of the major bottlenecks for its practical application. We report firstly that the microbial current generated by Shewanella loihica PV-4 (S. loihica PV-4) could be greatly improved that is up to ca. 115 fold, by adding antimony-doped tin oxide (ATO) nanoparticles in the electrochemical reactor. The results demonstrate that the biocompatible, electrically conductive ATO nanoparticles acted as active microelectrodes could facilitate the formation of a cells/ATO composite biofilm and the reduction of the outer membrane c-type cytochromes (OM c-Cyts) that are beneficial for the electron transfer from cells to electrode. Meanwhile, a synergistic effect between the participation of OM c-Cyts and the accelerated EET mediated by cell-secreted flavins may play an important role for the enhanced current generation in the presence of ATO nanoparticles. Moreover, it is worth noting that the TCA cycle in S. loihica PV-4 cells is activated by adding ATO nanoparticles, even if the potential is poised at +0.2 V, thereby also improving the EET process. The results presented here may provide a simple and effective strategy to boost the EET of S. loihica PV-4 cells, which is conducive to providing potential applications in bioelectrochemical systems.Dissimilatory metal reducing bacteria are capable of extracellular electron transfer (EET) to insoluble metal oxides as external electron acceptors for their anaerobic respiration, which is recognized as an important energy-conversion process in natural and engineered environments, such as in mineral cycling, bioremediation, and

  11. Effect of the antimony thin-film deposition sequence on copper-silicon interdiffusion: Vpliv zaporedja nanosa tankih plasti antimona na interdifuzijo baker-silicij:

    OpenAIRE

    Chaouki, Benazzouz; Fouzia, Zekkar; Mahfoud, Benkerri; Mokhtar, Boudissa; Mounir, Reffas; Nasser, Menni

    2012-01-01

    In this work we present a study of the effect of an antimony layer on the interdiffusion and formation of copper silicides while inverting the sequence of Cu and Sb deposition on Si(111) substrates. Thermal evaporation was used to deposit Cu/Sb and Sb/Cu bilayers on a Si(111) substrate heated at 100 °C, without breaking the vacuum. XRD and RBS analysis showed, for samples heat treated at 200 °C and 400 °C, a segregation of the three elements (i.e., Cu, Sb and Si) to the surface and diffusion ...

  12. Comparative study on the corrosion behavior of the cold rolled and hot rolled low-alloy steels containing copper and antimony in flue gas desulfurization environment

    Science.gov (United States)

    Park, S. A.; Kim, J. G.; He, Y. S.; Shin, K. S.; Yoon, J. B.

    2014-12-01

    The correlation between the corrosion and microstructual characteristics of cold rolled and hot rolled low-alloy steels containing copper and antimony was established. The corrosion behavior of the specimens used in flue gas desulfurization systems was examined by electrochemical and weight loss measurements in an aggressive solution of 16.9 vol % H2SO4 + 0.35 vol % HCl at 60°C, pH 0.3. It has been shown that the corrosion rate of hot rolled steel is lower than that of cold rolled steel. The corrosion rate of cold rolled steel was increased by grain refinement, inclusion formation, and preferred grain orientation.

  13. New and rapid access to synthesis of novel polysubstituted imidazoles using antimony trichloride and stannous chloride dihydrate as effective and reusable catalysts

    Indian Academy of Sciences (India)

    Leyla Poorali; Bahador Karami; Khalil Eskandari; Mahboobeh Azizi

    2013-05-01

    In this work, new, efficient and environmentally adapted synthesis of polysubstituted imidazoles in one-pot is repoted. The multicomponent reaction of various aldehydes, benzil, aliphatic and aromatic primary amines and ammonium acetate under solvent-free condition is explained. The highly efficient role of antimony trichloride and stannous chloride dihydrate as catalyst in this synthesis was shown and their effects on the reaction process were studied. By this advantage, several polysubstituted imidazoles as pharmaceutical important molecules can be prepared in high yield and high purity. This method is a very easy and rapid for the synthesis of imidazole derivatives.

  14. 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

  15. Preparation and Characterization of Antimony Doped Tin Oxide Thin Films Synthesized by Co-Evaporation of Sn and Sb using Plasma Assisted Thermal Evaporation

    Directory of Open Access Journals (Sweden)

    C. Jariwala

    2013-05-01

    Full Text Available Tin oxide (SnO2 thin films are having promising properties such as high visible transmittance and low electric resistivity, makes them very important transparent conductor in a variety of optoelectronics devices. Further, doping with pentavalent impurity such as Antimony (Sb enhances its conductivity considerably. In order to study the effect of Antimony doping, Antimony doped tin oxide (SnO2 : Sb thin films have been prepared by the co-evaporation of Sn and Sb using Plasma Assisted Thermal Evaporation (PATE in oxygen (O2 partial pressure at various doping level from 4% to 25%. The influence of various Sb doping levels on the compositional, electrical, optical and structural properties have been investigated using Energy Dispersive X-ray (EDX spectroscopy, Ultraviolet-Visible (UV-VIS transmission spectroscopy, four-probe resistivity measurement and X-ray Diffraction (XRD, respectively. EDX studies confirmed the different Sb doping levels in the grown films from 4 % to 25 %, while electrical resistivity is obtained in range of 0.36 to 9.5 Ohmcm using four-probe setup for 4 % to 25 % Sb doping levels. Transmittance spectra measured in UV-VIS range for Sb doped films show reduction in an average transmittance in respect to increase in Sb doping levels in the grown films. Whereas, XRD analysis reveals that higher Sb doping of 25 % induce the precipitation of antimony oxide (Sb2O3 phase and its precipitation suppressed the growth of SnO2 peaks as well as responsible for reduction in conductivity and transparency. The best electrical resistivity of optimized SnO2 : Sb (5 % is 0.36 Ohmcm without deteriorating the high (~ 80 % average transmittance in the wavelength region 300-800 nm in comparison to undoped SnO2 film (6.57 Ohmcm , confirm the usefulness of SnO2 : Sb (5 % films for device applications.

  16. Antimony (Sb) sorption studies on zircaloy, carbon steel (CS) and magnetite coated CS (MCS) surfaces in aqueous medium at pH 10.2 and 280℃

    International Nuclear Information System (INIS)

    Antimony sorption studies on zircaloy, CS and magnetite coated carbon steel (MCS) at primary heat transport temperature (290℃) of pressurised heavy water reactor (PHWR) are of direct relevance in investigating Sb activity problem faced in Indian PHWRs. Sb impregnated PHT pump carbon bearing releases Sb to reactor core. This Sb activates, and redeposit on out-of-core surfaces and results in exposure and apparent high decontamination factors. This Sb is not amenable to normal decantation. The form and state of deposited Sb is not yet fully known. This works attempts for this

  17. Molecular diversity of arbuscular mycorrhizal fungi at a large-scale antimony mining area in southern China.

    Science.gov (United States)

    Wei, Yuan; Chen, Zhipeng; Wu, Fengchang; Hou, Hong; Li, Jining; Shangguan, Yuxian; Zhang, Juan; Li, Fasheng; Zeng, Qingru

    2015-03-01

    Arbuscular mycorrhizal fungi (AMF) have great potential for assisting heavy metal hyperaccumulators in the remediation of contaminated soils. However, little information is available about the community composition of AMF under natural conditions in soils contaminated by antimony (Sb). The objective of this study was to investigate the characteristics of AMF molecular diversity, and to explore the effects of Sb content and soil properties on the AMF community structure in an Sb mining area. Four Sb mine spoils and one adjacent reference area were selected from around the Xikuangshan mine in southern China. The association of AMF molecular diversity and community composition with the rhizosphere soils of the dominant plant species was studied by Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis (PCR-DGGE). Results from all five studied sites showed that the diversity of AMF decreased with increasing Sb concentration. Principal component analysis (PCA) indicated that the AMF community structure was markedly different among these groups. Further redundancy analysis (RDA) showed that Sb contamination was the dominating factor influencing the AMF community structure in the Sb mine area. However, the multivariate analysis showed that, apart from the soil Sb content, extractable nitrogen content and organic matter content also attributed to AMF sequence distribution type. Some AMF sequences were only found in the highly contaminated area and these might be ideal candidates for improving phytoremediation efficiency in Sb mining regions. Gene sequencing analysis revealed that most species were affiliated with Glomus, suggesting that Glomus was the dominant AMF genus in the studied Sb mining area. PMID:25766009

  18. 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.

  19. 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.

  20. Migration and leaching risk of extraneous antimony in three representative soils of China: lysimeter and batch experiments.

    Science.gov (United States)

    Hou, H; Yao, N; Li, J N; Wei, Y; Zhao, L; Zhang, J; Li, F S

    2013-11-01

    Antimony (Sb) distribution, solubility and mobility onto natural soils of China were studied in lysimeter and batch experiments as a function of physicochemical properties of the soil. An outdoor lysimeter experiment investigated the leaching and migration of Sb in the soils with Sb-polluted topsoil and unpolluted subsoil over a 5month period. Soil solutions were collected by suction cups installed at different depth of lysimeters, and leachates were regularly collected and analyzed for Sb concentrations. The majority of the added Sb was retained in the topsoil layers, but small portions were moved to the sub-layers. Sb concentrations in the soil solutions and leachates ranged from 0-755.5 (6.38±54 on average) μg l(-1) and 0-0.45 (smaller than the detection limit) μg l(-1) respectively, indicating the low solubility of Sb in the soils. Batch experiments were performed in order to determine the sorption capacity and the partition coefficient (Kd). Freundlich isotherm described properly the equilibrium experimental data and results show that the Kd values for Primosol, Isohumosol, Ferrosol equal to 22.5, 87.8, 704 L kg(-1), respectively. These results showed the strong capacity of the soils to retain Sb, and prevent it being leached down the profile. The mobilizable Sb was in the order: Primosol>Isohumosol>Ferrosol. Sb migration in the soils was mainly associated with the exchangeable, carbonate-bound, and metal-organic complex-bound fractions. Health risk assessment indicates that Sb leaching from Ferrosol will not harm to human health through groundwater under the test conditions, while it has certain health risks from the Isohumosol and Primosol. PMID:23931906

  1. Responses and acclimation of Chinese cork oak (Quercus variabilis Bl.) to metal stress: the inducible antimony tolerance in oak trees.

    Science.gov (United States)

    Zhao, Xiulian; Zheng, Lingyu; Xia, Xinli; Yin, Weilun; Lei, Jingpin; Shi, Shengqing; Shi, Xiang; Li, Huiqing; Li, Qinghe; Wei, Yuan; Chang, Ermei; Jiang, Zeping; Liu, Jianfeng

    2015-08-01

    Antimony (Sb) pollution has become a pressing environmental problem in recent years. Trees have been proven to have great potential for the feasible phytomanagement; however, little is known about Sb retention and tolerance in trees. The Chinese cork oak (Quercus variabilis Bl.) is known to be capable of growth in soils containing high concentrations of Sb. This study explored in detail the retention and acclimation of Q. variabilis under moderate and high external Sb levels. Results revealed that Q. variabilis could tolerate and accumulate high Sb (1623.39 mg kg(-1) DW) in roots. Dynamics of Sb retention in leaves, stems, and roots of Q. variabilis were different. Leaf Sb remained at a certain level for several weeks, while in roots and stems, Sb concentrations continued to increase. Sb damaged tree's PSII reaction cores but elicited defense mechanism at the donor side of PSII. It affected the electron transport flow after QA (-) more strongly than the oxygen-evolving complex and light-harvesting pigment-protein complex II. Sb also decreased leaf chlorophyll concentrations and therefore inhibited plant growth. During acclimation to Sb toxicity, Sb concentrations in leaves, stems, and roots decreased, with photosynthetic activity and pigments recovering to normal levels by the end of the experiment. These findings suggest that Sb tolerance in Q. variabilis is inducible. Acclimation seems to be related to homeostasis of Sb in plants. Results of this study can provide useful information for trees breeding and selection of Sb phytomanagement strategies, exploiting the established ability of Q. variabilis to transport, delocalize in the leaves, and tolerate Sb pollutions.

  2. Bacillus sp.处理含锑废水试验研究%Bacillus sp. Treatment of Wastewater Containing Antimony

    Institute of Scientific and Technical Information of China (English)

    李小娇; 陈平; 陈才丽; 成应向; 龚道新; 向仁军; 王强强

    2013-01-01

    Antimony ore dressing wastewater was treated by using Bacil us sp. and the influences of treatment time, temperature, inoculation size, and pH value on Sb removal effect were explored. The results showed that the best removal efficiency of Sb in mineral processing wastewater could reach 99.75% in 4 d under the optimum conditions of 30 ℃, microbial inoculated quantity 5%, and pH value at 2.0. After the treatment, the concentration of Sb in wastewater was reduced from 122.21 to 0.30 mg/L, which was lower than the local industrial wastewater discharge standard of 0.50 mg/L.%利用某芽孢杆菌属微生物( Bacillus sp.)对锑矿选矿废水进行了处理。研究微生物的接种量、作用时间、温度、体系 pH值等对废水中Sb的去除效果的影响。结果表明:作用时间4 d微生物接种量为5处理体系 pH为2最佳处理体系温度为30时,效果最佳,对废水中Sb的去除率达到99.75%,处理后废水中 Sb的浓度由122.21 mg/L降低至0.30 mg/L,出水Sb浓度低于湖南省地方标准排放限值0.50 mg/L。

  3. Correlating microbial community profiles with geochemical conditions in a watershed heavily contaminated by an antimony tailing pond.

    Science.gov (United States)

    Xiao, Enzong; Krumins, Valdis; Tang, Song; Xiao, Tangfu; Ning, Zengping; Lan, Xiaolong; Sun, Weimin

    2016-08-01

    Mining activities have introduced various pollutants to surrounding aquatic and terrestrial environments, causing adverse impacts to the environment. Indigenous microbial communities are responsible for the biogeochemical cycling of pollutants in diverse environments, indicating the potential for bioremediation of such pollutants. Antimony (Sb) has been extensively mined in China and Sb contamination in mining areas has been frequently encountered. To date, however, the microbial composition and structure in response to Sb contamination has remained overlooked. Sb and As frequently co-occur in sulfide-rich ores, and co-contamination of Sb and As is observed in some mining areas. We characterized, for the first time, the microbial community profiles and their responses to Sb and As pollution from a watershed heavily contaminated by Sb tailing pond in Southwest China. The indigenous microbial communities were profiled by high-throughput sequencing from 16 sediment samples (535,390 valid reads). The comprehensive geochemical data (specifically, physical-chemical properties and different Sb and As extraction fractions) were obtained from river water and sediments at different depths as well. Canonical correspondence analysis (CCA) demonstrated that a suite of in situ geochemical and physical factors significantly structured the overall microbial community compositions. Further, we found significant correlations between individual phylotypes (bacterial genera) and the geochemical fractions of Sb and As by Spearman rank correlation. A number of taxonomic groups were positively correlated with the Sb and As extractable fractions and various Sb and As species in sediment, suggesting potential roles of these phylotypes in Sb biogeochemical cycling. PMID:27182975

  4. 甲基异丁基甲酮萃取—氢化物发生原子荧光光谱法测定锑锭和氧化锑中汞%Determination of mercury in antimony ingot and antimony oxide by methyl isobutyl ketone extraction-hydride generation atomic fluorescence spectrometry

    Institute of Scientific and Technical Information of China (English)

    陆建平; 谭芳维; 石建荣

    2012-01-01

    After the samples were dissolved in aqua regia/HBr and tartaric acid was added to mask antimony, then mercury in antimony ingot and antimony oxide was extracted into the organic phase with methyl isobutyl ketone (MIBK) and determined by organic phase injection-intermittent flow injection atomic fluorescence spectrometry. Sample dissolution methods and interferences caused by coexisting ions were investigated, and instrument working conditions, extraction conditions, acidity and other factors were optimized. The results showed that under optimal conditions, the mercury content within the range of 0. 02 to 50 μg/L was in good linear relationship, and the detection limit was 0. 013 jxg/L. This method was applied to the actual antimony ingot and antimony oxide sample analysis. It was found that the results were consistent with those obtained by inductive coupled plasma atomic emission spectrometry with relative standard deviations (RSDs, n = 6) of 0. 65%-2. 4% and recoveries of 94 %-99%.%采用王水/HBr溶解样品,酒石酸掩蔽锑,用甲基异丁基甲酮(MIBK)将汞萃取到有机相中,建立了有机相进样—断续流动注射原子荧光光谱法测定锑锭和氧化锑中汞含量的方法.研究了溶样方法和共存离子可能引起的干扰,优化了仪器工作条件、萃取条件、酸度及其他影响因素.结果表明,在最佳条件下,汞含量在0.02~50 μg/L范围内线性关系良好,方法检出限为0.013 μg/L.将方法应用于锑锭和氧化锑实际样品分析,测得结果与电感耦合等离子体原子发射光谱法一致,相对标准偏差(RSD,n=6)在0.65%~2.4%之间,加标回收率为94%~99%.

  5. 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.

  6. Stability studies of arsenic, selenium, antimony and tellurium species in water, urine, fish and soil extracts using HPLC/ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Lindemann, T.; Prange, A.; Neidhart, B. [GKSS Research Centre, Geesthacht (Germany). Inst. of Physical and Chemical Analysis; Dannecker, W. [Hamburg Univ. (Germany). Inst. fuer Anorganische und Angewandte Chemie

    2000-10-01

    The stability of arsenic, selenium, antimony and tellurium species in water and urine (NIST SRM 2670n) as well as in extracts of fish and soil certified reference materials (DORM-2 and NIST SRM 2710) has been investigated. Stability studies were carried out with As(III), As(V), arsenobetaine, monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), phenylarsonic acid (PAA), Se(IV), Se(VI), selenomethionine, Sb(III), Sb(V) and Te(VI). Speciation analysis was performed by on-line coupling of anion exchange high-performance liquid chromatography (HPLC) with inductively coupled plasma mass spectrometry (ICP-MS). Best storage of aqueous mixtures of the examined species was achieved at 3 C whereas at -20 C species transformation especially of selenomethionine and Sb(V) took place and a new selenium species appeared within a period of 30 days. Losses and species transformations during extraction processes were investigated. Extraction of the spiked fish material with methanol/water led to partial conversion of Sb(III), Sb(V) and selenomethionine to two new antimony and one new selenium species. The other arsenic, selenium and tellurium species were almost quantitatively extracted. For soil spiked with MMA, PAA, Se(IV) and Sb(III), recoveries after extraction with water and sulfuric acid (0.01 mol/L) were below 20%. (orig.)

  7. Antimony(v) cations for the selective catalytic transformation of aldehydes into symmetric ethers, α,β-unsaturated aldehydes, and 1,3,5-trioxanes.

    Science.gov (United States)

    Arias Ugarte, Renzo; Devarajan, Deepa; Mushinski, Ryan M; Hudnall, Todd W

    2016-07-01

    1-Diphenylphosphinonaphthyl-8-triphenylstibonium triflate ([][OTf]) was prepared in excellent yield by treating 1-lithio-8-diphenylphosphinonaphthalene with dibromotriphenylstiborane followed by halide abstraction with AgOTf. This antimony(v) cation was found to be stable toward oxygen and water, and exhibited exceptional Lewis acidity. The Lewis acidity of [][OTf] was exploited in the catalytic reductive coupling of a variety of aldehydes into symmetric ethers of type in good to excellent yields under mild conditions using Et3SiH as the reductant. Additionally, [][OTf] was found to selectively catalyze the Aldol condensation reaction to afford α-β unsaturated aldehydes () when aldehydes with 2 α-hydrogen atoms were used. Finally, [][OTf] catalyzed the cyclotrimerization of aliphatic and aromatic aldehydes to afford the industrially-useful 1,3,5 trioxanes () in good yields, and with great selectivity. This phosphine-stibonium motif represents one of the first catalytic systems of its kind that is able to catalyze these reactions with aldehydes in a controlled, efficient manner. The mechanism of these processes has been explored both experimentally and theoretically. In all cases the Lewis acidic nature of the antimony(v) cation was found to promote these reactions. PMID:27326797

  8. Annealing effects on structural, electrical and optical properties of antimony-tinoxide thin films deposited by sol gel dip coating technique

    Energy Technology Data Exchange (ETDEWEB)

    Lekshmy, S. Sujatha, E-mail: jolly2jolly@gmail.com; Anitha, V. S., E-mail: jolly2jolly@gmail.com; Berlin, I. John, E-mail: jolly2jolly@gmail.com; Joy, K., E-mail: jolly2jolly@gmail.com [Thin film Laboratory, Post Graduate and Research Department of Physics, Mar Ivanios College, Thiruvananthapuram 695 015 (India)

    2014-01-28

    Antimony-doped tin dioxide possess interesting physical and chemical properties. These properties have a wide range of applications such as catalysis and optoelectronic devices. In the present study, antimony-doped tin oxide (SnO2:Sb) thin films were deposited on the quartz substrates by sol-gel dip coating technique. The films were annealed at temperatures 350°C, 550°C and 850°C in air for 2 hours. The structure and surface morphologies were observed by X-ray diffraction (XRD) and Scanning electron microscopy (SEM). XRD patterns shows tetragonal structure for the SnO2:Sb films annealed at different temperatures. Crystallite size increased from 6 to 14 nm as annealing temperature increased from 350°C to 850°C. SEM studies reveals crack free and smooth surface for all the films. The grains are found to be homogenously distributed for films annealed at higher temperature. The electrical conductivity of the films annealed at 350°C and 550°C decreased and increased for the films annealed at 850°C. The optical properties of the films were investigated in the UV-visible-NIR region (200-900 nm) using UV spectra. The transmittance of the films decreased for films annealed at higher temperature. The optical energy band gap values (4.13 eV-4.83 eV) increased with the increase in annealing temperature.

  9. 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

  10. Investigation on spread and risk factors of tuberculosis in antimony miners%锑矿工结核病传播及危险因素调查

    Institute of Scientific and Technical Information of China (English)

    陈开森; 刘涛; 林瑞瑞; 罗涛; 杨崇广

    2015-01-01

    Objective To explore the infection rate of tuberculosis ( TB) and its risk factors in antimony miners .Methods With cluster sampling method , the strains identification and drug sensitive test were performed in Mycobacterium tuberculosis ( MTB) of 263 TB patients in antimony miners .The method of 12 sites mycobacterial interspersed repetitive unit and variable number of tandem repeat wre used to determine the genetic type of MTB .Risk factors of TB spread were assessed by chi-square test.Results The TB infection rate in antimony miners was 9.8%(472/4 831);among 263 TB cases, 175 cases were found clustered the clustering rate was 66.5%, the least estimated recent TB spread rate was 53.2%.High TB spread rate was found in the antimony miners with failed treatment , length of service longer than 10 years , multidrug-resistant bacterial strains , and positive sputum smear .Conclusion The MTB of antimony miners showed the clustering feature and the bacterial strains had strong toxicity and higher spreading rate .The major risk factors affecting TB spread were therapeutic effect , length of service , drug resistant bacterial strain and sputum smear result .%目的 了解锑矿工肺结核感染率及感染的危险因素. 方法 采用整群抽样方法,对263例锑矿工肺结核患者进行结核分枝杆菌的菌株鉴定和药敏试验. 基因分型采用12位点结核分枝杆菌散在分布重复单元和多位点串联重复序列;采用X2检验评估结核传播的危险因素. 结果 锑矿工肺结核的感染率为9.8%(472/4 831); 纳入研究的263例患者中,175例成簇,成簇率为66 .5%,近期传播率最低估计值为53 .2%. 治疗失败、工龄大于10年、菌株多重耐药及痰涂片阳性的锑矿工肺结核传播率较高. 结论 锑矿工结核分枝杆菌具有成簇性,其菌株毒力更强、传播率高,治疗效果、矿龄、菌株耐药性及痰涂片结果是影响肺结核传播的重要危险因素.

  11. 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

  12. 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...

  13. Study on the Synthesis Processing and Content Determination of Corn Silk Polysaccharide Selenide%硒化玉米须多糖的工艺条件及硒含量测定研究

    Institute of Scientific and Technical Information of China (English)

    侯巍; 朱小庆; 楚婧; 高金波

    2012-01-01

    OBJECTIVE Using the polysaccharide from corn silk as the raw material, to study the selenizing process with sodium selenite. METHODS Selenizing conditions were established by single factor and orthogonal design; determining content of polysaccharide selenide by Se( IV )-KSCN-MV extraction spectrophotometry; characterizing the structure of polysaccharide selenide by IR. RESULTS The optimal conditions were: 70 ℃ reaction temperature, 8 hours reaction time, mass ratio of com silk polysaccharide to sodium selenite 1 : 1.2, 0.3% HNO3 of volume fraction. The average content of selenium in corn silk polysaccharide was over 3.17 mg·g‐1 and average yield was 35.72%. IR results showed that corn silk polysaccharide contained Se=O and Se-C. CONCLUSION Corn silk polysaccharide selenide is successfully synthesized and the study provides the foundation for further study and exploiting for corn silk.%目的 以玉米须多糖为原料,用亚硒酸钠进行玉米须多糖的硒化研究.方法 利用单因素和正交试验确立硒化的最佳工艺条件;利用硒-硫氰酸钾-甲基紫萃取光度法测定硒多糖中的硒含量,并通过红外光谱对硒多糖进行了初步表征.结果 最佳工艺条件为反应温度70℃,反应时间8h,玉米须多糖与亚硒酸钠质量比为1∶1.2,硝酸体积分数为0.3%,玉米须硒多糖中硒含量为3.17 mg·g-1,平均收率为35.72%.红外光谱显示:玉米须硒多糖中含有Se=O键和Se-C键.结论 利用该工艺成功合成了玉米须硒多糖,为玉米须的开发和利用奠定基础.

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

    Science.gov (United States)

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

    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 15days), 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 111.3mg/kg. The Sb concentration (0.28-2.30μg/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 5μg/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 pH7 stored at 75°C for a period of 5days. 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 400ng/kg/day, with values of 514.3 and 566.2ng/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. PMID:27192700

  15. Characteristics of some selenides and the physical-chemical condition of selenides and tellurides in the Jílové gold metallogenic concentration area,Czech Republic%捷克Jílové金矿集区中硒矿物的特征与硒化物-碲化物的形成物理化学条件

    Institute of Scientific and Technical Information of China (English)

    刘家军; 杨隆勃; 翟德高; 吴杰

    2013-01-01

    the Middle Ages. The important gold de-posits include the Pepf, Bohuliby, Radlik and Rotlev. They exist mainly in the Upper Proterozoic volcano-sed-iment of the Stechovice Group and the granodiorite of the Central Bohemian Pluton. There are three types of gold mineralization in the Jilovegold metallogenic concentration area: veins, stockworks, impregnation. Up to now, more than 70 minerals have been identified. They include not only sulfides and sulfosalts of Cu,Pb,Zn, Fe, As,Mo,Bi, Hg, Au, and Ag-bearing minerals,a variety of oxide,hydroxide, sulfate,carbonate, tungstate and silicate minerals but also telluride,halide, and native metals. Examination of ores by optical microscope, electron probe,X-ray surface scanning,has revealed that there are some selenides in the deposits. The diversity of mineral species in the ores and the occurrence of visible native gold minerals are the outstanding features of the gold deposit. Generally speaking, the more robust correlation is with the chalcogenidic environment and, in most cases, the lesser correlation with specific minerals. Therefore, the highly enrichment of selenide and telluride in the deposits is very characteristic, reflecting a specific condition of their formation. In the early stage of mineralization, f(Se2), f(Te2) and f(O2) are relatively low while f(S2) is relatively high, with f(S2)/f(Se2)>1 and f(S2>/f(Te2)>1. In this circumstance, sulfur would be precipitated as sulfides while selenium and tellurium would tend to be trapped in the sulfides as isomorphous admixture. Therefore, the min-erals are characterized by the association of pyrite, marcasite, pyrrhotite, arsenopyrite, chalcopyrite, galenite, sphalerite and so on. In the late stage of mineralization, f(Se2), f(Te2), and f(O2) are relatively high while f(S2) is relatively low, with f(S2)/f(Se2)<1 and f(S2)/f(Te2)<1. In the main stage of mineralization, f(Se2 )/f(S2), f(Te2 )/f(S2) and f(O2) would increase with the precipitation of sulfides, which would

  16. 锡、锑对铅及铅合金中铜元素检测的干扰探究%Detection of Copper Element in Lead and Lead Alloy, the Inquiry of the Interference about Tin,Antimony

    Institute of Scientific and Technical Information of China (English)

    常守森

    2016-01-01

    本文对国家标准(GB/T 74.4———2000)进行了研究。对含高锑、高锡、高锑锡的铅合金中铜含量的测定进行了重点探究。在样品溶解,试样处理以及测定过程三方面加以探究,获得了满意结果。采取先加入助溶络合剂(酒石酸、柠檬酸、Na2EDTA)帮助溶解样品并防止锑、锡水解,然后再分别除去助溶络合剂以及锡、锑等元素的干扰,从而达到准确测定的目的。测定范围:0.00050%~0.60%。%The national standard (GB/T74 .4-2000)was studied . The determination of copper in lead and lead alloy , the influence of high antimony , high tin or high antimony and tin was mainly discussed . Three aspects were explored :dissolve process , operation process and determination process of sample . Satisfac‐tory results had already obtained . Adding hydrotropy complexing agent ( tartaric acid , citric acid , Na2 EDTA) into the sample at first for dissolve the sample and preventing the hydrolysis of antimony or tin , and then to remove hydrotropy complexing agent , the elements such as tin and antimony . It can elim‐inate the influence of tartaric acid , citric acid , Na2 EDTA and the elements such as tin and antimony , thus achieve the purpose of accurate determination . Measuring range is 0 .00050% ~ 0 .60% .

  17. Research on the Flotation of a Gold - antimony Ore in Gansu%甘肃某金锑矿选矿试验研究

    Institute of Scientific and Technical Information of China (English)

    吉庆军

    2012-01-01

    The systematical flotation experiments were conducted on a gold - antimony ore in Gansu based on mineralogy. When the grinding fineness was 82% -0. 074 mm, sodium silicate was used as ganguefe depressant, lead nitrate as activator, and the mixture of sodium ethyl xanthate and ammonium dibutyl dithiophosphate as selective flotation collectors, an antimony concentrate of 50. 67% Sb could be obtained with a recovery of 78.43% . Then the mixture of sodium sulfide and copper sulfate were used as activators of gold - bearing mineral in antimony tailings, combined collectors was also used, and benzyl hydroxamic acid was used to enhance gold flotation. A gold concentrate containing 60. 89 g/t Au could be obtained with a recovery of 80. 52% .%以甘肃某金锑矿为研究对象,在矿石工艺矿物学研究的基础上,通过系统的浮选试验,对含锑0.73%、金2.42 g/t的原矿,确定在磨矿细度为-0.074 mm占82%时,采用单一的水玻璃作为脉石矿物抑制剂,以硝酸铅活化含锑矿物,混合使用乙基黄药和丁铵黑药优先浮选锑,组合采用硫化钠与硫酸铜活化浮锑尾矿中的载金矿物,混合使用Y89黄药和丁铵黑药浮金,浮金回路添加少量苯甲羟肟酸以强化浮选效果,实验室小型闭路试验可获得锑精矿品位50.67%、回收率78.43%;金精矿含金60.89 g/t、回收率80.52%的选矿指标.

  18. 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.

    Science.gov (United States)

    Urgut, O S; Ozturk, I I; Banti, C N; Kourkoumelis, N; Manoli, M; Tasiopoulos, A J; Hadjikakou, S K

    2016-01-01

    Antimony(III) halide complexes of the formulae {[SbBr(Me2DTC)2]n} (1), {[SbI(Me2DTC)2]n} (2) and {[(Me2DTC)2Sb(μ2-I)Sb(Me2DTC)2](+).I3(-)} (3) (Me2DTC = dimethyldithiocarbomate) were synthesized from SbX3, (X = Br or I) and tetramethylthiuram monosulfide (Me4tms) or tetramethylthiuram disulfide (Me4tds). 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 ((1)H,(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(+)-Sb and an I3(-) 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. PMID:26478326

  19. 黔西南一小型锑冶炼厂环境污染调查分析%Investigation and Analysis on Environmental Pollution Due to a Small Antimony Smeltery in Southwest Guizhou Province

    Institute of Scientific and Technical Information of China (English)

    张军营; 钟秦; 任德贻

    2001-01-01

    Objective To understand the impacts of a small antimony smeltery on surrounding environment. Methods The samples of raw materials,such as ore and coal,soil and plant around a small antimony smeltery in southwest Guizhou province were analyzed. Results The levels of arsenic,mercury,fluoride ,antimony and selenium in soil around the antimony smeltery significantly increased compared with the average background levels of related elements in nationwide range . The levels of arsenic, mercury,fluoride ,antimony and selenium in soil around the antimony smeltery were 1. 73~4.69,4. 75~237.5,2. 26~3.42,35.6~36. 2,54. 29~57.14 times as much as their related average levels in our country respectively. The levels of arsenic ,mercury ,fluoride and selenium in soil around the smeltery were 1.25~ 3. , 58,1.86~ 93.14,1.38~ 2.08,33. 04~ 34.78 times as much as their related average levels of Guizhou province respectively. The levels of arsenic, mercury, fluoride, antimony and selenium in corn leaves around the smeltery was 67,26.7,1046.4,2220,38. 8 times as much as their related average levels in non-polluted plants respectively. Conclusion The air pollutants,such as sulphur,arsenic,mercury,fluoride,antimony and selenium in industrial waste gas emitted from the antimony smeltery had resulted in heavy pollution to the environment, which was aggravated by the application of coal with high level of sulphur.%目的了解小型锑冶炼厂对周围环境的影响。方法对黔西南一小型锑冶炼厂矿石、燃用煤以及周围土壤和植物样品进行了分析。结果锑冶炼厂周围土壤中元素含量与全国土壤中元素平均含量比较,As、Hg、F、Sb、Se的含量明显偏高,As为1. 73~4.96倍,Hg为4.75~237.5倍,F为2.26~3.42倍,Sb为35.6~36.2倍,Se为54.29~57.14倍;也高于贵州土壤的平均含量,As为1. 25~3.58倍,Hg为1.86~93.14倍,F为1.38~2.08倍,Se为33.04~34.78倍。玉米叶片中As、Hg、F

  20. 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.

  1. 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)

  2. Behavior of antimony isotopes in the primary coolant of WWER-1000-type nuclear reactors in NPP Kozloduy during operation and shutdown

    Energy Technology Data Exchange (ETDEWEB)

    Dobrevski, Ivan D.; Zaharieva, Neli N. [Bulgarian Academy of Sciences, Sofia (Bulgaria). Inst. for Nuclear Research and Nuclear Energy; Minkova, Katia F.; Gerchev, Nikolay B. [Kozloduy Nuclear Power Plant, Kozloduy (Bulgaria). Dept. of Chemistry and Radiochemistry

    2009-05-15

    This paper focuses on the behavior of the antimony isotopes {sup 122}Sb and {sup 124}Sb in the coolant of the WWER reactors in the nuclear power plant Kozloduy (Bulgaria) during operation and shutdown. It is concluded that the chemical properties of their actual precursor, the isotope {sup 121}Sb, determine the behavior of {sup 122}Sb and {sup 124}Sb during operation, load fluctuations, and shutdown as well as during the reactor coolant purification process. It is supposed that differences between the reactor bulk and the core fuel cladding surface chemistry as well as the presence of sub-cooled nucleate boiling at the fuel cladding may create conditions under which a local oxidizing environment may come into existence. (orig.)

  3. 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

  4. Study of ion chromatographic behavior of inorganic and organic antimony species by using inductively coupled plasma mass spectrometric (ICP-MS) detection

    Energy Technology Data Exchange (ETDEWEB)

    Ulrich, N. [University of Hannover, Department of Inorganic Chemistry (Germany)

    1998-04-01

    An on-line method for the analysis of Sb(III), Sb(V) and trimethylstiboxide (TMSbO) is presented. The separation is performed using ion chromatography (IC) on a strong anion-exchange column with phthalic acid plus 2% acteone at pH 5 as mobile phase. The chromatographic system is coupled to an ICP-MS as detector. The influence of different complexing agents on the chromatographic behavior of the antimony species is studied. Rather stable complexes of Sb(III) seem to be formed with citrate and tartrate under the experimental conditions. TMSbO forms a dianionic species with citrate in contrast to the otherwise monoanionic complex. (orig.) With 3 figs., 2 tabs., 8 refs.

  5. Comparison of the native antimony-bearing Paiting gold deposit, Guizhou Province, China, with Carlin-type gold deposits, Nevada, USA

    Science.gov (United States)

    Xie, Zhuo-Jun; Xia, Yong; Cline, Jean S.; Yan, Bao-Wen; Wang, Ze-Peng; Tan, Qin-Ping; Wei, Dong-Tian

    2016-03-01

    The Paiting gold deposit, Guizhou Province, China, has been regarded as a Carlin-type gold deposit by several researchers. Alteration and ore-related minerals from the Paiting deposit were examined, and results were compared with the Cortez Hills Carlin-type gold deposit, Nevada, USA. Similarities include the structural and stratigraphic controls on the orebodies in both deposits and the occurrence of invisible gold ionically bound in arsenian pyrite. Significant differences include the following: (1) The gold-bearing mineral in Nevada is arsenian pyrite. However, gold-bearing minerals in the Paiting deposit include arsenopyrite, arsenian pyrite, and trace pyrrhotite. Also, euhedral or subhedral gold-bearing arsenian pyrite at Paiting contains significantly less As, Cu, and Hg than gold-bearing pyrite from Nevada. (2) Alteration in the Paiting deposit displays significantly less decarbonatization. Instead, dolomite precipitation, which has not been described in Nevada deposits, is associated with deposition of gold-bearing sulfide minerals. (3) Stibnite and minor native antimony typify Paiting late-ore-stage minerals, whereas in Nevada, realgar, orpiment, and calcite are common late-ore-stage minerals. Precipitation of native antimony in the Paiting deposit reflects the evolution of a late-ore fluid with unusually low sulfur and oxygen fugacities. Some characteristics of the Paiting gold deposit, including formation of ore-stage dolomite and precipitation from CO2-rich ore fluids at temperatures in excess of 250 °C, are more typical of orogenic deposits than Nevada Carlin deposits. The presence of similarities in the Paiting deposit to both Carlin type and orogenic deposits is consistent with formation conditions intermediate to those typical of Carlin type and orogenic systems.

  6. Study on Cobalt Removal with Antimony Trioxide in Zinc Hydrometallurgy%湿法炼锌锑盐除钴工艺的研究

    Institute of Scientific and Technical Information of China (English)

    姜艳; 谢刚; 肖锐敏; 李自静; 孙丽达; 黄笃树

    2013-01-01

    采用三氧化二锑对湿法炼锌的硫酸锌溶液进行净化除钴.考察锌粉用量、三氧化二锑用量、锌粉粒度、搅拌速度、温度、时间等对净化除钴效果的影响.结果表明,细粒度锌粉和强烈搅拌除钴效果较好,在合适的温度和时间下也能达到净化要求.最优除钴工艺条件为:三氧化二锑3 mg/L,锌粉2 g/L,锌粉粒度0.074~0.050 mm,搅拌转速300 r/min,温度85℃和时间90 min.%Cobalt in zinc sulfate solution from zinc hydrometallurgy was purified with antimony trioxide.The effects of dosage of zinc powder and antimony trioxide,particle size of zinc powder,stirring rate,temperature,and time on cobalt removal were examined.The results show that good cobalt removal effect can be achieved with fine-grained zinc powder by strong mixing and purification requirements can be met in appropriate temperature and time.The optimum conditions for cobalt removal include dosage of Sb2O3 of 3 mg/L,dosage of zinc powder of 2 g/L,zinc powder particle size of 0.074~0.050 mm,stirring rate of 300 r/min,temperature of 85 C and time of 90 min.

  7. Association of liposome-encapsulated trivalent antimonial with ascorbic acid: an effective and safe strategy in the treatment of experimental visceral leishmaniasis.

    Directory of Open Access Journals (Sweden)

    Renata A O Castro

    Full Text Available 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

  8. 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. PMID:24632364

  9. Geomicrobiological cycling of antimony

    Science.gov (United States)

    Kulp, T. R.; Terry, L.; Dovick, M. A.; Braiotta, F.

    2013-12-01

    Microbiologically catalyzed oxidation and reduction of toxic metalloids (e.g., As, Se, and Te) generally proceeds much faster than corresponding abiotic reactions. These microbial transformations constitute biogeochemical cycles that control chemical speciation and environmental behavior of metalloids in aqueous environments. Particular progress has been made over the past two decades in documenting microbiological biotransformations of As, which include anaerobic respiratory reduction of As(V) to As(III), oxidation of As(III) to As(V) linked to chemoautotrophy or photoautotrophy, and cellular detoxification pathways. By contrast, microbial interactions with Sb, As's group 15 neighbor and a toxic element of emerging global concern, are poorly understood. Our work with sediment microcosms, enrichment cultures, and bacterial isolates suggests that prokaryotic metabolisms may be similarly important to environmental Sb cycling. Enrichment cultures and isolates from a Sb-contaminated mine site in Idaho exhibited Sb(V)-dependent heterotrophic respiration under anaerobic conditions and Sb(III)-dependent autotrophic growth in the presence of air. Live, anoxic cultures reduced 2 mM Sb(V) to Sb(III) within 5 d, while no activity occurred in killed controls. Sb(V) reduction was stimulated by lactate or acetate and was quantitatively coupled to the oxidation of lactate. The oxidation of radiolabeled 14C-acetate (monitored by GC-GPC) demonstrated Sb(V)-dependent oxidation to 14CO2, suggesting a dissimilatory process. Sb(V) dependent growth in cultures was demonstrated by direct counting. Microbiological reduction of Sb(V) also occurred in anerobic sediment microcosms from an uncontaminated suburban lake, but did not appear to be linked to growth and is interpreted as a mechanism of biological detoxification. Aerobic microcosms and cultures from the Idaho mine oxidized 2 mM Sb(III) to Sb(V) within 7 d and coupled this reaction to cell growth quantified by direct counting. An anoxygenic photosynthetic community of purple sulfur bacteria from Pyramid Lake, NV, however, that was capable of growth via anoxygenic photosynthesis using As(III) as an electron donor was not capable of similar growth using Sb(III). These results suggest that geomicrobiological Sb cycling is an important influence on the environmental speciation and behavior of Sb, and portend the presence of a global biogeochemical Sb cycle that is analogous to but distinct from that for As.

  10. 水、土环境中锑污染与控制研究进展%Research progress on present situation and countermeasure of antimony pollution in water and soil environment

    Institute of Scientific and Technical Information of China (English)

    张亚平; 张婷; 陈锦芳; 彭然

    2011-01-01

    随着工业的发展,锑作为一种具有潜在毒性和致癌性的类金属元素,已经较为广泛地存在于水体和土壤环境中,显现出不可忽视的环境问题,并引起国际科学界的高度关注.文章综述了锑在水体和土壤环境中的污染现状、化学行为形态以及污染控制方面的研究进展.由采矿业、制造业带来的锑水土污染问题较为突出,目前的处理处置方法难以满足需求.今后需要在锑的水土环境化学方面加强研究,探讨锑的迁移转化规律;高效吸附材料的开发制备也是一个重要内容;植物组合修复土壤中的锑污染将是一个重要的突破口.%Antimony exists widely in water and soil environment with the development of industry. It has brought out noticeable environment problems, and has drawn quite a lot of attentions from scientists, as a metalloid element with potentially toxicity and carcinogenicity. Current pollution status, species and biogeochemical behaviour of antimony in water and soil, and research on the contamination control were viewed in this paper. Pollution of antimony in water and soil caused by mining and manufacturing has become increasingly seriously, and the methods to deal with it can hardly meet the demands. As a result, some works as follows need to be done: research in the environmental chemistry of antimony in water and soil should be strengthened in the future, as well as exploring the principle of antimony in movement and transformation. Development and preparation of new materials with efficient adsorbability are also important. Moreover, phytoremediation combination technology to remedy pollution of antimony in soil may be another important breakthrough.

  11. Determination of arsenic in antimony ingot and antimony trioxide by hydride generation-atomic fluorescence spectrometry%氢化物发生-原子荧光光谱法测定锑锭及三氧化二锑中的砷

    Institute of Scientific and Technical Information of China (English)

    钱光敏; 赵国杏

    2012-01-01

    The antimony slab and antimonous oxide samples were dissolved by sulfuric acid and hydrochloric acid, respectively. The Sb3+ in solution was precipitated with sodium hydroxide to separate trace arsenic from matrix antimony. The thiourea-ascorbic acid was added to reduce As5+ to As3+. Then, the arsenic in antimony slab and antimonous oxide was determined by atomic fluorescence spec-trometry. The hydride generation conditions were investigated: the concentration of reducing agent potassium borohydride was 25 g/L, the determination medium was 20% (V/V) hydrochloric acid, and the dosage of thiourea - ascorbic acid solution was 5 mL. The interference test of coexisting elements showed that, the interference of residual antimony in solution after precipitation could be fully eliminated by adding 1 mL of tartaric acid solution. Other impurity elements in sample did not interfere with the determination of arsenic after adding thiourea-ascorbic acid solution. The detection limit of method was 0. 156 ng/mL. The antimony slab and antimonous oxide samples were analyzed by the proposed method, and the relative standard deviation (RSD) was 0. 95%-1.2%. The determination results were consistent with those obtained by national standard methods.%采用硫酸溶解锑锭样品,盐酸溶解三氧化二锑样品,用氢氧化钠溶液使Sb3+沉淀从而使基体锑与微量砷分离,通过加入硫脲-抗坏血酸将As5+还原成As3+,然后在原子荧光仪上测定锑锭及三氧化二锑中的砷.对氢化物发生条件进行考察,确定还原剂硼氢化钾的浓度为25 g/L、测定介质为20%(V/V)盐酸、硫脲-抗坏血酸溶液用量为5 mL.共存元素干扰试验表明,沉淀后溶液中残留少量锑的干扰在加入1 mL酒石酸溶液后可以完全消除,而样品中其他杂质元素在加入硫脲-抗坏血酸溶液后不干扰砷的测定.方法的检出限为0.156 ng/mL.对锑锭及三氧化二锑样品进行分析,相对标准偏差为0.95%~1.2%,测定

  12. Tetra-Antimony(III)-Bridged 18-Tungsto-2-Arsenates(V), [(LSb(III))4(A-α-As(V)W9O34)2](10-) (L = Ph, OH): Turning Bioactivity On and Off by Ligand Substitution.

    Science.gov (United States)

    Yang, Peng; Lin, Zhengguo; Bassil, Bassem S; Alfaro-Espinoza, Gabriela; Ullrich, Matthias S; Li, Ming-Xing; Silvestru, Cristian; Kortz, Ulrich

    2016-04-18

    Two tetra-antimony(III)-bridged, sandwich-type 18-tungsto-2-arsenates(V), [(LSb(III))4(A-α-As(V)W9O34)2](10-) (L = Ph (1), OH (2)), were prepared and fully characterized in the solid state and in solution. Both polyanions are stable in aqueous physiological medium for at least 24 h (at concentrations ≥2.5 × 10(-6) M). Despite the presence of an isostructural tetra-antimony(III) motif in 1 and 2, distinctly different antibacterial activity was observed for both polyanions. The minimum inhibitory concentrations (MIC) of 1 (7.8-62.5 μg/mL) is lower than for any other organoantimony(III)-containing polyoxometalate reported to date.

  13. Tetra-Antimony(III)-Bridged 18-Tungsto-2-Arsenates(V), [(LSb(III))4(A-α-As(V)W9O34)2](10-) (L = Ph, OH): Turning Bioactivity On and Off by Ligand Substitution.

    Science.gov (United States)

    Yang, Peng; Lin, Zhengguo; Bassil, Bassem S; Alfaro-Espinoza, Gabriela; Ullrich, Matthias S; Li, Ming-Xing; Silvestru, Cristian; Kortz, Ulrich

    2016-04-18

    Two tetra-antimony(III)-bridged, sandwich-type 18-tungsto-2-arsenates(V), [(LSb(III))4(A-α-As(V)W9O34)2](10-) (L = Ph (1), OH (2)), were prepared and fully characterized in the solid state and in solution. Both polyanions are stable in aqueous physiological medium for at least 24 h (at concentrations ≥2.5 × 10(-6) M). Despite the presence of an isostructural tetra-antimony(III) motif in 1 and 2, distinctly different antibacterial activity was observed for both polyanions. The minimum inhibitory concentrations (MIC) of 1 (7.8-62.5 μg/mL) is lower than for any other organoantimony(III)-containing polyoxometalate reported to date. PMID:27043954

  14. Normal coordinate analysis and quantum chemical study of tris(-fluorophenyl)antimony di(-phenylglycinate) [(-FC6H4)3Sb(O2CCH2NHC6H5)2

    Indian Academy of Sciences (India)

    Tanveer Hasan; P K Singh; K Singhal; P Raj; Neeraj Misra

    2007-10-01

    A complete normal coordinate analysis was performed by two different methods: a classical Wilson's G-F matrix method and the semi-empirical molecular orbital PM3 method, for a five coordinate tris(-fluorophenyl)antimony di( -phenylglycinate) [(-FC6H4)3Sb(O2CCH2NHC6H5)2], known to be an in vitro antitumour molecule.

  15. Structural consideration of antimony pentafluoride deposited on metal oxides (SiO2, Al2O3, and SiO2-Al2O3) by X-ray absorption (EXAFS/XANES) spectroscopy

    International Nuclear Information System (INIS)

    Using EXAFS/XANES, the structural environments of antimony pentafluoride deposited on SiO2, Al2O3, and SiO2-Al2O3 oxides are investigated to generate strong acid sites on the oxides. Sb-ligand bond lengths for SbF5 deposited on the oxides vary depending on the type of oxide. 31 refs., 6 figs., 2 tabs

  16. Combined effect of strontium modifier and antimony refiner on texture and growth mode of eutectic phase in an Al-11Si-2Cu-0.8Zn-0.6Fe cast alloy

    Science.gov (United States)

    Farahany, Saeed; Ourdjini, Ali; Hekmat-Ardakan, Alireza

    2015-12-01

    Results of electron back-scattered diffraction and transmission electron microscopy studies reveal that the orientation of aluminium in the eutectic phase is different from the surrounding aluminium dendrites and that twin spacing of eutectic silicon increased significantly due to the interaction between strontium and antimony. In addition, the formation of ternary Mg2Sb2Sr intermetallic compound that precedes the eutectic reaction was proposed to be responsible for interaction.

  17. The application of lead-antimony-rare earth alloy in the power batterys%低锑稀土合金在动力电池中的应用

    Institute of Scientific and Technical Information of China (English)

    郭志刚; 刘玉; 徐明学; 邓成智; 周文渭; 曹进; 李桂发

    2015-01-01

    本文针对目前市场上出现的一种新型铅锑稀土合金,从合金的成分、耐腐蚀性,电池初期性能及循环使用寿命等方面进行了研究。试验结果表明:该合金具有较好的耐腐蚀性能,对电池初期性能也不会带来明显的影响,但在循环使用过程中,会使电池失水严重,从而造成使用寿命缩短。%This paper mainly discussed a lead-antimony-rare earth alloy which was used as the grid material of lead-acid batteries. The chemical composition and corrosion resistance of the lead-antimony-rare earth alloy, and initial performance and cycle life of lead-acid batteries with the lead-antimony-rare earth alloy were studied. The experimental results showed that the alloy had a good corrosion resistance, and didn’t impact the initial performance of the battery. However, it would lead to a shortened service life of lead-acid batteries because of severe water loss.

  18. On-line cloud point extraction combined with electrothermal vaporization inductively coupled plasma atomic emission spectrometry for the speciation of inorganic antimony in environmental and biological samples

    Energy Technology Data Exchange (ETDEWEB)

    Li Yingjie [Department of Chemistry, Wuhan University, Wuhan 430072 (China); Hu Bin [Department of Chemistry, Wuhan University, Wuhan 430072 (China)]. E-mail: binhu@whu.edu.cn; Jiang Zucheng [Department of Chemistry, Wuhan University, Wuhan 430072 (China)

    2006-08-25

    A new method for the determination of inorganic Sb species by on-line cloud point extraction combined with electrothermal vaporization inductively coupled plasma atomic emission spectrometry (ETV-ICP-AES) is presented and evaluated. The method is based on the complexation of Sb(III) with pyrrolidine dithiocarbamate (PDC) which form an hydrophobic complex at pH 5.5 and subsequently enter surfactant-rich phase at pH 5.5, whereas Sb(V) remained in aqueous solutions. The preconcentration step is mediated by micelles of the non-ionic surfactant Triton X-114 with ammonium pyrrolidine dithiocarbamate (APDC). The micellar system containing the complex was loaded into the FIA manifold at a flow rate of 2.5 mL min{sup -1}, and the surfactant-rich phase was retained in a microcolumn packed with absorbent cotton, at pH 5.5. After the surfactant-rich phase was eluted with 100 {mu}L acetonitrile, it was determined by ETV-ICP-AES. Sb(V) is reduced to Sb(III) by L-cysteine prior to determined total Sb, and its assay is based on subtracting Sb(III) from total antimony. The main factors affecting separation/preconcentration and the vaporization behavior of analyte in graphite tube were investigated in detail. Under the optimized conditions, the precision relative standard deviation (R.S.D.) for eight replicate measurements of 0.2 {mu}g mL{sup -1} Sb(III) was 4.3%. The apparent concentration factor, which is defined as the concentration ratio of the analyte in the final diluted surfactant-rich extract ready for ETV-ICP-AES detection and in the initial solution, was 872 for Sb(III). The limit of detection (LOD) for Sb(III) was 0.09 {mu}g L{sup -1}. The proposed method was successfully applied for the speciation of inorganic antimony in different water samples and urine sample with satisfactory results.

  19. Adsorption of antimony(V) onto Mn(II)-enriched surfaces of manganese-oxide and FeMn binary oxide.

    Science.gov (United States)

    Liu, Ruiping; Xu, Wei; He, Zan; Lan, Huachun; Liu, Huijuan; Qu, Jiuhui; Prasai, Tista

    2015-11-01

    Manganese(IV) oxide [Mn(IV)] potentially oxidizes antimony(III) [Sb(III)] to antimony(V) [Sb(V)] and improves Sb removal by FeMn binary oxide (FMBO) through an oxidation-adsorption mechanism. This study focused on the effect of Mn(IV) reductive dissolution by potassium sulfite (K2SO3) on Sb(V) adsorption onto manganese oxide (Mn-oxide) and FMBO. The maximum Sb(V) adsorption (Qmax,Sb(V)) increased from 1.0 to 1.1 mmol g(-1) for FMBO and from 0.4 to 0.6 mmol g(-1) for Mn-oxide after pretreatment with 10 mmol L(-1) K2SO3. The addition of 2.5 mmol L(-1) Mn(2+) also significantly improved Sb(V) adsorption, and the observed Qmax,Sb(V) increased to 1.4 and 1.0 mmol g(-1) for FMBO and Mn-oxide, respectively, with pre-adsorbed Mn(2+). Neither K2SO3 nor Mn(2+) addition had any effect on Sb(V) adsorption onto iron oxide (Fe-oxide). Mn(2+) introduced by either Mn(IV) dissolution or addition tended to form outer-sphere surface complexes with hydroxyl groups on Mn-oxide surfaces (MnOOH). Mn(2+) at 2.5 mmol L(-1) shifted the isoelectric point (pHiep) from 7.5 to 10.2 for FMBO and from 4.8 to 9.2 for Mn-oxide and hence benefited Sb(V) adsorption. The adsorption of Sb(V) onto Mn(2+)-enriched surfaces contributed to the release of Mn(2+), and the X-ray photoelectron spectra also indicated increased binding energy of Mn 2p3/2 after the adsorption of Sb(V) onto K2SO3-pretreated FMBO and Mn-oxide. Sb(V) adsorption involved the formation of inner-sphere complexes and contributed to the release of Mn(2+). In the removal of Sb(III) by Mn-based oxides, the oxidation of Sb(III) to Sb(V) by Mn(IV) oxides had an effect; however, Mn(IV) dissolution and Mn(2+)-enrichment also played an important role.

  20. 锑金精矿挥发特性及机理研究%Research on Volatilization Performance and Mechanism of Gold-bearing Antimony Concentrates

    Institute of Scientific and Technical Information of China (English)

    杨永斌; 刘庆华; 李骞; 姜涛; 郭宇峰

    2012-01-01

    研究了锑金精矿在氮气、氧气和一氧化碳三种气氛中的挥发特性,通过综合分析Sb、S两种元素的挥发行为,结合焙砂的微观形态分析,研究了三种气氛中的挥发反应机理.结果表明,锑金精矿在三种不同气氛下所发生的挥发反应各不相同.氮气气氛中,Sb2S3直接挥发;一氧化碳气氛中,除部分Sb2S3直接挥发外,还有一部分Sb2S3被还原成难挥发的金属Sb以熔融态的形式残留在焙砂中,同时生成COS气态产物进入气相;氧气气氛中,Sb2S3被气相中的O2氧化,一部分生成难挥发的Sb2O4残留在焙砂中,另一部分以Sb2O3的形态挥发进入气相.%Research was carried out on volatilization performance of gold-bearing antimony concentrate in three different atmospheres such as N2, O2, CO. The volatilization reaction mechanism was studied by analyzing volatilization behaviour of Sb and S, as well as the micro-morphology of calcine. The results showed that volatilization reactions of gold-bearing antimony concentrate differed in three different atmospheres. In N2 atmosphere, Sb2S3 volatilized directly. In CO atmosphere, only a part of Sb2S3 volatilized directly and the rest part was reduced to low-volatile or non-volatile molten metal (Sb) which was remained in the calcine, generating gaseous product COS to enter into gas phase. In O2 atmosphere, Sb2S3 was oxidized by O2, partly being as low-volatile Sh2O3 remained in the calcine and partly in the form of Sb2O3 volatilized into gas phase.