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Sample records for antimony iodides

  1. Determination of antimony in concentrates, ores and non-ferrous materials by atomic-absorption spectrophotometry after iron-lanthanum collection, or by the iodide method after further xanthate extraction.

    Science.gov (United States)

    Donaldson, E M

    1979-11-01

    Methods for determining trace and moderate amounts of antimony in copper, nickel, molybdenum, lead and zinc concentrates and in ores are described. Following sample decomposition, antimony is oxidized to antimony(V) with aqua regia, then reduced to antimony(III) with sodium metabisulphite in 6M hydrochloric acid medium and separated from most of the matrix elements by co-precipitation with hydrous ferric and lanthanum oxides. Antimony (>/= 100 mug/g) can subsequently be determined by atomic-absorption spectrophotometry, at 217.6 nm after dissolution of the precipitate in 3M hydrochloric acid. Alternatively, for the determination of antimony at levels of 1 mug/g or more, the precipitate is dissolved in 5M hydrochloric acid containing stannous chloride as a reluctant for iron(III) and thiourea as a complexing agent for copper. Then tin is complexed with hydrofluoric acid, and antimony is separated from iron, tin, lead and other co-precipitated elements, including lanthanum, by chloroform extraction of its xanthate. It is then determined spectrophotometrically, at 331 or 425 nm as the iodide. Interference from co-extracted bismuth is eliminated by washing the extract with hydrochloric acid of the same acid concentration as the medium used for extraction. Interference from co-extracted molybdenum, which causes high results at 331 nm, is avoided by measuring the absorbance at 425 nm. The proposed methods are also applicable to high-purity copper metal and copper- and lead-base alloys. In the spectrophotometric iodide method, the importance of the preliminary oxidation of all of the antimony to antimony(V), to avoid the formation of an unreactive species, is shown.

  2. Potassium Iodide

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    Potassium iodide is used to protect the thyroid gland from taking in radioactive iodine that may be released ... damage the thyroid gland. You should only take potassium iodide if there is a nuclear radiation emergency and ...

  3. On line automated system for the determination of Sb(V), Sb(III), thrimethyl antimony(v) and total antimony in soil employing multisyringe flow injection analysis coupled to HG-AFS.

    Science.gov (United States)

    Silva Junior, Mario M; Portugal, Lindomar A; Serra, Antonio M; Ferrer, Laura; Cerdà, Victor; Ferreira, Sergio L C

    2017-04-01

    This paper proposes the use of a multisyringe flow injection analysis (MSFIA) system for inorganic antimony speciation analysis, trimethyl antimony(V) and determination of total antimony in soil samples using hydride generation atomic fluorescence spectrometry (HG-AFS). Total antimony has been determined after reduction of antimony(V) to antimony(III) using potassium iodide and ascorbic acid. For determination of total inorganic antimony the sample is percolated in a mini-column containing the Dowex 50W-X8 resin for retention of the organic species of antimony. Antimony(III) is quantified in presence of 8-hydroxyquinoline as masking agent for antimony(V) after an extraction step of the organic antimony species using the also same mini-column. The trimethyl antimony(V) content is found by difference between total antimony and total inorganic antimony. By other hand, antimony(V) is quantified by difference between total inorganic antimony and antimony(III). The analytical determinations were performed using sodium tetrahydroborate as reducing agent. The optimization step was performed using two-level full factorial design and Doehlert matrix involving the factors: hydrochloric acid and sodium tetrahydroborate concentrations and sample flow rate. The optimized experimental conditions allow the antimony determination utilizing the external calibration technique with limits of detection and quantification of 0.9 and 3.1ngg(-1), respectively, and a precision expressed as relative standard deviation of 3.2% for an antimony solution of 5.0µgL(-1). The method accuracy was confirmed by analysis of the soil certified reference material furnished from Sigma-Aldrich RTC. Additionally, addition/recovery tests were performed employing synthetic solutions prepared using trimethyl antimony(V), antimony(III), antimony(V) and five soil samples. The antimony extraction step was performed in a closed system using hydrochloric acid, ultrasonic radiation and controlled temperature. The

  4. Potassium Iodide (KI)

    Science.gov (United States)

    ... Health Matters Information on Specific Types of Emergencies Potassium Iodide (KI) Language: English Español (Spanish) Recommend on Facebook ... can I get KI (potassium iodide)? What is Potassium Iodide (KI)? KI (potassium iodide) is a salt of ...

  5. Antimony: a flame fighter

    Science.gov (United States)

    Wintzer, Niki E.; Guberman, David E.

    2015-01-01

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

  6. Oligosilanylated Antimony Compounds

    Science.gov (United States)

    2015-01-01

    By reactions of magnesium oligosilanides with SbCl3, a number of oligosilanylated antimony compounds were obtained. When oligosilanyl dianions were used, either the expected cyclic disilylated halostibine was obtained or alternatively the formation of a distibine was observed. Deliberate formation of the distibine from the disilylated halostibine was achieved by reductive coupling with C8K. Computational studies of Sb–Sb bond energies, barriers of pyramidal inversion at Sb, and the conformational behavior of distibines provided insight for the understanding of the spectroscopic properties. PMID:25937691

  7. Synthesis of nanoscale antimony particles

    Energy Technology Data Exchange (ETDEWEB)

    Balan, L.; Dailly, A. [Universite Henri Poincare Nancy I, Laboratoire de Chimie du Solide Mineral, UMR 7555 CNRS (France); Schneider, R. [Universite Henri Poincare Nancy I, Laboratoire de Synthese organometallique et Reactivite, UMR 7565 CNRS (France); Billaud, D., E-mail: Denis.Billaud@lcsm.uhp-nancy.fr [Universite Henri Poincare Nancy I, Laboratoire de Chimie du Solide Mineral, UMR 7555 CNRS (France); Willmann, P. [Centre National d' Etudes Spatiales, (France); Olivier-Fourcade, J.; Jumas, J.-C. [Universite Montpellier, Laboratoire des Agregats Moleculaires et Materiaux Inorganiques, UMR 5072 CNRS (France)

    2005-09-15

    For the search of new negative electrodes of Li-ion batteries, a low-temperature method has been developed for the preparation of nanoscale antimony particles which uses an alkoxide-activated sodium hydride as reducing agent of antimony pentachloride. X-ray diffraction and TEM studies confirm the obtaining of amorphous Sb nanoparticles dispersed in an organic matrix. {sup 121}Sb Moessbauer spectroscopy gives evidence for the occurrence of interactions between antimony and the matrix. These interactions are modified by the washing treatments.

  8. dl-Alaninium iodide

    Directory of Open Access Journals (Sweden)

    Kevin Lamberts

    2012-06-01

    Full Text Available The crystal structure of dl-alanine hydroiodide (1-carboxyethanaminium iodide, C3H8NO2+·I−, is that of an organic salt consisting of N-protonated cations and iodide anions. The compound features homochiral helices of N—H...O hydrogen-bonded cations in the [010] direction; neighbouring chains are related by crystallographic inversion centers and hence show opposite chirality. The iodide counter-anions act as hydrogen-bond acceptors towards H atoms of the ammonium and carboxy groups, and cross-link the chains along [100]. Thus, an overall two-dimensional network is formed in the ab plane. No short contacts occur between iodide anions.

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

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    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. 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.

  11. Study on extraction separation of antimony(Ⅲ) by n-propyl alcohol-potassium iodide-ammonium sulfate system in the presence of ascorbic acid%在抗坏血酸存在下正丙醇-碘化钾-硫酸铵体系萃 分离锑(Ⅲ)的研究

    Institute of Scientific and Technical Information of China (English)

    郭鹏; 司学芝; 牛媛媛; 钟黎

    2011-01-01

    The behavior and conditions of extraction separation and concentration of Sb(Ⅲ) from other metal ions by n-propyl alcohol-potassium iodide-ammonium sulfate system in the presence of ascorbic acid were investigated. The results showed that n-propyl alcohol aqueous solution could be well divided into two phases when ammonia sulfate was added. The complex [SbI4-][C3H7OH2+ ] formed by Sbi4 4(the reaction product of Sb(Ⅲ) with potassium iodide) and protonized n-propyl alcohol (C3H7OH2+) could be fully extracted by n-propyl alcohol phase in phase separation process. When the system contained 0. 40 mol/L potassium iodide, 0. 2 g/Ml ammonia sulfate and 30% n-propyl alcohol (V/V). Sb(Ⅲ) was well separated from Pb(II),Mn(II)tFe(Ⅲ),Zn(Ⅱ), A1(II),Cr(Ⅲ),Ni(II},Cu(Ⅱ) and Mg(II), and the extraction recoveries of Sb(Ⅲ) was over 96. 9%.%研究了在抗坏血酸存在下正丙醇-碘化钾-硫酸铵体系萃取分离和富集Sb(Ⅲ)的行为及与一些金属离子分离的条件.结果表明,硫酸铵能使正丙醇的水溶液分成两相,在分相过程中,Sb(Ⅲ)与碘化钾生成的(SbI4-)与质子化正丙醇(C3 H7 OH2+)形成的缔合物[SbI4][C3 H7 OH2+]能被正丙醇相完全萃取.当正丙醇、碘化钾和硫酸铵的浓度分别为30%(V/V)、0.40 mol/L、0.20 g/mL时,Sb(Ⅲ)的萃取率达到96.9%以上,Pb(Ⅱ),Mn(Ⅱ),Fe(Ⅲ),Zn(Ⅱ),Al(Ⅲ),Cr(Ⅲ),Ni(Ⅱ),Cu(Ⅱ)和Mg(Ⅱ)基本不被萃取,实现了Sb(Ⅲ)与上述金属离子的分离.

  12. 21 CFR 184.1265 - Cuprous iodide.

    Science.gov (United States)

    2010-04-01

    ... with potassium iodide under slightly acidic conditions. (b) The ingredient must be of a purity suitable... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Cuprous iodide. 184.1265 Section 184.1265 Food and... Substances Affirmed as GRAS § 184.1265 Cuprous iodide. (a) Cuprous iodide (copper (I) iodide, CuI, CAS...

  13. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; determination of antimony by automated-hydride atomic absorption spectrophotometry

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    Brown, G.E.; McLain, B.J.

    1994-01-01

    The analysis of natural-water samples for antimony by automated-hydride atomic absorption spectrophotometry is described. Samples are prepared for analysis by addition of potassium and hydrochloric acid followed by an autoclave digestion. After the digestion, potassium iodide and sodium borohydride are added automatically. Antimony hydride (stibine) gas is generated, then swept into a heated quartz cell for determination of antimony by atomic absorption spectrophotometry. Precision and accuracy data are presented. Results obtained on standard reference water samples agree with means established by interlaboratory studies. Spike recoveries for actual samples range from 90 to 114 percent. Replicate analyses of water samples of varying matrices give relative standard deviations from 3 to 10 percent.

  14. 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.

  15. Synthesis of mercuric iodide and bismuth tri-iodide nanoparticles for heavy metal iodide films nucleation

    Energy Technology Data Exchange (ETDEWEB)

    Fornaro, L.; Pereira, H.Bentos [Compound Semiconductors Group, CURE, Universidad de la Republica, Rocha (Uruguay); Aguiar, I.; Perez Barthaburu, M. [Compound Semiconductors Group, Facultad de Quimica, Univ. de la Republica, Montevideo (Uruguay)

    2011-12-15

    We synthesized mercuric iodide and bismuth tri-iodide nanoparticles by suspension in octadecene, from Hg(NO{sub 3}){sub 2}.H{sub 2}O and I{sub 2}, and from Bi(NO{sub 3}){sub 3}.5H{sub 2}O and I{sub 2}, respectively. The best synthesis conditions were 2 h at 70-80 C, followed by 10 min at 110 C for mercuric iodide nanoparticles, and 4 h at 80-110 C, followed by 10 min at 180-210 C for bismuth tri-iodide ones. Nanoparticles were then washed and centrifuged with ether repeatedly. Compounds identity was confirmed by X-ray diffraction (XRD) and energy dispersive spectrometry (EDS). We found shifts of the X-ray diffraction maxima for nanoparticles of both compounds. We characterized the nanoparticles by transmission (TEM) and scanning (SEM) electron microscopy. We obtained disk-like and squared mercuric iodide nanostructures, 80-140 nm and 100-125 nm in size respectively. We also obtained rounded and rod-like bismuth tri-iodide nanoparticles, 30-500 nm in size. Acetonitrile and isopropanol suspensions of mercuric iodide nanoparticles, and acetonitrile suspension of bismuth tri-iodide nanoparticles exhibited peak maxima shifts in their UV-Vis spectra. We synthesized for the first time mercuric iodide and bismuth tri-iodide nanoparticles by the suspension method, although we have not yet obtained uniform shape and size distributions. They offer interesting perspectives for crystalline film nucleation and for improving current applications of these materials, as well as for opening new ones. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  16. 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.

  17. 21 CFR 172.375 - Potassium iodide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium iodide. 172.375 Section 172.375 Food and... Dietary and Nutritional Additives § 172.375 Potassium iodide. The food additive potassium iodide may be safely used in accordance with the following prescribed conditions: (a) Potassium iodide may be...

  18. Iodide transport and breast cancer.

    Science.gov (United States)

    Poole, Vikki L; McCabe, Christopher J

    2015-10-01

    Breast cancer is the second most common cancer worldwide and the leading cause of cancer death in women, with incidence rates that continue to rise. The heterogeneity of the disease makes breast cancer exceptionally difficult to treat, particularly for those patients with triple-negative disease. To address the therapeutic complexity of these tumours, new strategies for diagnosis and treatment are urgently required. The ability of lactating and malignant breast cells to uptake and transport iodide has led to the hypothesis that radioiodide therapy could be a potentially viable treatment for many breast cancer patients. Understanding how iodide is transported, and the factors regulating the expression and function of the proteins responsible for iodide transport, is critical for translating this hypothesis into reality. This review covers the three known iodide transporters - the sodium iodide symporter, pendrin and the sodium-coupled monocarboxylate transporter - and their role in iodide transport in breast cells, along with efforts to manipulate them to increase the potential for radioiodide therapy as a treatment for breast cancer.

  19. 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....

  20. 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.

  1. Perspectives of antimony compounds in oncology

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    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.

  2. Novel methods for the encapsulation of meglumine antimoniate into liposomes

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    F. Frézard

    2000-07-01

    Full Text Available The antimonial drug, meglumine antimoniate, was successfully encapsulated in dehydration-rehydration vesicles and in freeze-dried empty liposomes (FDELs. High encapsulation efficiencies (from 28 to 58% and low weight ratios of lipids to encapsulated antimony (from 1:0.15 to 1:0.3 were achieved. These formulations, contrary to those obtained by conventional methods, can be stored as intermediate lyophilized forms and reconstituted just before use. The efficacy of FDEL-encapsulated meglumine antimoniate was evaluated in hamsters experimentally infected with Leishmania chagasi. A significant reduction of liver parasite burdens was observed in animals treated with this preparation, when compared to control animals treated with empty liposomes. In contrast, free meglumine antimoniate was found to be inefficient when administered at a comparable dose of antimony. This novel liposome-based meglumine antimoniate formulation appears to be promising as a pharmaceutical product for the treatment of visceral leishmaniasis.

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

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    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.”

  4. Frequently Asked Questions on Potassium Iodide (KI)

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    ... Bioterrorism and Drug Preparedness Frequently Asked Questions on Potassium Iodide (KI) Share Tweet Linkedin Pin it More sharing ... Drug Administration (FDA) issued a final Guidance on Potassium Iodide as a Thyroid Blocking Agent in Radiation Emergencies) ( ...

  5. 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.

  6. 21 CFR 582.5634 - Potassium iodide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Potassium iodide. 582.5634 Section 582.5634 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5634 Potassium iodide. (a) Product. Potassium iodide. (b) Tolerance. 0.01 percent....

  7. 21 CFR 184.1634 - Potassium iodide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium iodide. 184.1634 Section 184.1634 Food... Specific Substances Affirmed as GRAS § 184.1634 Potassium iodide. (a) Potassium iodide (KI, CAS Reg. No. 7681-11-0) is the potassium salt of hydriodic acid. It occurs naturally in sea water and in...

  8. Bismuth tri-iodide radiation detector development

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    Gokhale, Sasmit S.

    Bismuth tri-iodide is an attractive material for room temperature radiation detection. BiI3 demonstrates a number of properties that are apt for semiconductor radiation detection, especially gamma ray spectroscopy. The high atomic number (ZBi = 83 and ZI = 53) and the relatively high density (5.78 g/cm3) cause the material to have good photon stopping power, while the large band-gap (1.67 eV ) allows it to function as a room temperature radiation detector without any cooling mechanism. This work presents the fabrication and characterization of BiI3 radiation detectors. For the purpose of this research detectors were fabricated by cutting BiI3 crystal boules, followed by mechanical and chemical surface treatments. Detectors with various electrode geometries enabling single polarity charge sensing were fabricated. The electrical characteristics and the radiation response of the detectors were measured. The radiation response measurement was performed at room temperature using a 241Am alpha particle source and a 241Am sealed gamma-ray source. The spectral resolutions of the detectors varied from 2.09% - 6.1% for 59.5 keV gamma-rays and between 26% - 40% for 5.48 MeV alpha particles. Charge carrier properties such as the electron and hole mobility and lifetime were also estimated. The electron mobility for an ultrapure BiI 3 detector was estimated to be approximately 433 cm 2/Vs while that for antimony doped BiI3 was estimated to be around 956 cm2/Vs and the mobility-lifetime product for electrons was estimated to be around 5.44 x 10-4 cm 2/V. Detector simulation was performed using the Monte Carlo simulation code MCNP5. A Matlab script which incorporates charge carrier trapping and statistical variation was written to generate a gamma-ray spectrum from the simulated energy deposition spectra. Measured and simulated spectra were compared to extract the charge carrier mobility-lifetime products, which for electrons and holes were estimated to be 5 x 10-3 cm2/V and 1.3 x

  9. 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)

  10. Resistance mechanisms to arsenicals and antimonials.

    Science.gov (United States)

    Rosen, B P

    1995-01-01

    Salts and organic derivatives of arsenic and antimony are quite toxic. Living organisms have adapted to this toxicity by the evolution of resistance mechanisms. Both prokaryotic and eukaryotic cells develop resistance when exposed to arsenicals or antimonials. In the case of bacteria resistance is conferred by plasmid-encoded arsenical resistance (ars) operons. The genes and gene products of the ars operon of the clinically-isolated conjugative R-factor R773 have been identified and their mechanism of action elucidated. The operon encodes an ATP-driven pump that extrudes arsenite and antimonite from the cells. The lowering of their intracellular concentration results in resistance. Arsenate resistance results from the action of the plasmid-encoded arsenate reductase that reduces arsenate to arsenite, which is then pumped out of the cell.

  11. Cobalt and antimony: genotoxicity and carcinogenicity.

    Science.gov (United States)

    De Boeck, Marlies; Kirsch-Volders, Micheline; Lison, Dominique

    2003-12-10

    The purpose of this review is to summarise the data concerning genotoxicity and carcinogenicity of Co and Sb. Both metals have multiple industrial and/or therapeutical applications, depending on the considered species. Cobalt is used for the production of alloys and hard metal (cemented carbide), diamond polishing, drying agents, pigments and catalysts. Occupational exposure to cobalt may result in adverse health effects in different organs or tissues. Antimony trioxide is primarily used as a flame retardant in rubber, plastics, pigments, adhesives, textiles, and paper. Antimony potassium tartrate has been used worldwide as an anti-shistosomal drug. Pentavalent antimony compounds have been used for the treatment of leishmaniasis. Co(II) ions are genotoxic in vitro and in vivo, and carcinogenic in rodents. Co metal is genotoxic in vitro. Hard metal dust, of which occupational exposure is linked to an increased lung cancer risk, is proven to be genotoxic in vitro and in vivo. Possibly, production of active oxygen species and/or DNA repair inhibition are mechanisms involved. Given the recently provided proof for in vitro and in vivo genotoxic potential of hard metal dust, the mechanistic evidence of elevated production of active oxygen species and the epidemiological data on increased cancer risk, it may be advisable to consider the possibility of a new evaluation by IARC. Both trivalent and pentavalent antimony compounds are generally negative in non-mammalian genotoxicity tests, while mammalian test systems usually give positive results for Sb(III) and negative results for Sb(V) compounds. Assessment of the in vivo potential of Sb2O3 to induce chromosome aberrations (CA) gave conflicting results. Animal carcinogenicity data were concluded sufficient for Sb2O3 by IARC. Human carcinogenicity data is difficult to evaluate given the frequent co-exposure to arsenic. Possible mechanisms of action, including potential to produce active oxygen species and to interfere with

  12. The heat capacity of solid antimony selenide

    Science.gov (United States)

    Pashinkin, A. S.; Malkova, A. S.; Mikhailova, M. S.

    2008-06-01

    The literature data on the heat capacity of solid antimony selenide over the temperature range 53 K- T m were analyzed. The heat capacity of Sb2Se3 was measured from 350 to 600 K on a DSM-2M calorimeter. The experimental data were used to calculate the dependence C p = a + bT + cT -2 and the thermodynamic functions of solid Sb2Se3 over the temperature range 298.15 700 K.

  13. Thermodynamics of congruently subliming cerium-antimony

    Energy Technology Data Exchange (ETDEWEB)

    Schiffman, R.A.; Franzen, H.F.

    1982-01-01

    Congruently vaporizing cerium-antimony has been investigated by vapor pressure measurementa using a simultaneous weight-loss mass-spectrometric Knudsen effusion technique. The melting point of the 1:1 stoichiometry was determined to be 2179 +/- 10 K. The heat of formation at 298 K of CeSb was found to be -128.9 kJ/g-at from thermodynamic measurements in the temperature range 1985-2172 K.

  14. The exposure to and health effects of antimony

    DEFF Research Database (Denmark)

    Cooper, Ross G.; Harrison, Adrian Paul

    2009-01-01

    of the eyes, skin, and lungs. Long-term inhalation of antimony can potentiate pneumoconiosis, altered electrocardiograms, stomach pain, diarrhea, vomiting, and stomach ulcers, results which were confirmed in laboratory animals. Although there were investigations of the effect of antimony in sudden infant...... death syndrome, current findings suggest no link. Antimony trioxide exposure is predominant in smelters. Mining and exposure via glass working, soldering, and brazing are also important. Conclusion: Antimony has some useful but undoubtedly harmful effects on health and well-being and measures need...

  15. THE CRYSTAL STRUCTURE OF ANTIMONY (III) SULFOBROMIDE, SBSBR,

    Science.gov (United States)

    ANTIMONY COMPOUNDS, *SULFUR COMPOUNDS, CRYSTAL STRUCTURE , CRYSTAL STRUCTURE , BROMIDES, SYMMETRY(CRYSTALLOGRAPHY), FOURIER ANALYSIS, MOLECULAR STRUCTURE, CRYSTAL LATTICES, CHEMICAL BONDS, X RAY DIFFRACTION.

  16. Comparing polyaluminum chloride and ferric chloride for antimony removal.

    Science.gov (United States)

    Kang, Meea; Kamei, Tasuku; Magara, Yasumoto

    2003-10-01

    Antimony has been one of the contaminants required to be regulated, however, only limited information has been collected to date regarding antimony removal by polyaluminium chloride (PACl) and ferric chloride (FC). Accordingly, the possible use of coagulation by PACl or FC for antimony removal was investigated. Jar tests were used to determine the effects of solution pH, coagulant dosage, and pre-chlorination on the removal of various antimony species. Although high-efficiency antimony removal by aluminum coagulation has been expected because antimony is similar to arsenic in that both antimony and arsenic are a kind of metalloid in group V of the periodic chart, this study indicated: (1) removal density (arsenic or antimony removed per mg coagulant) for antimony by PACl was about one forty-fifth as low as observed for As(V); (2) although the removal of both Sb(III) and Sb(V) by coagulation with FC was much higher than that of PACl, a high coagulant dose of 10.5mg of FeL(-1) at optimal pH of 5.0 was still not sufficient to meet the standard antimony level of 2 microg as SbL(-1) for drinking water when around 6 microg as SbL(-1) were initially present. Consequently, investigation of a more appropriate treatment process is necessary to develop economical Sb reduction; (3) although previous studies concluded that As(V) is more effectively removed than As(III), this study showed that the removal of Sb(III) by coagulation with FC was much more pronounced than that of Sb(V); (4) oxidation of Sb(III) with chlorine decreased the ability of FC to remove antimony. Accordingly, natural water containing Sb(III) under anoxic condition should be coagulated without pre-oxidation.

  17. [Rare, severe hypersensitivity reaction to potassium iodide].

    Science.gov (United States)

    Korsholm, Anne Sofie; Ebbehøj, Eva; Richelsen, Bjørn

    2014-07-07

    The literature reports a large variety of adverse reactions to potassium iodide. A severe hypersensitivity reaction to potassium iodide in a 51-year-old woman with Graves' thyrotoxicosis is described. Following administration the patient developed sialadenitis, conjunctivitis, stomatitis and acneiform iododerma that responded dramatically to withdrawal of the potassium iodide and administration with corticosteroids. Awareness of these adverse reactions may prevent prolonged hospitalization and unnecessary tests and treatments.

  18. Uptake of iodide in the marine haptophyte Isochrysis sp. (T.ISO) driven by iodide oxidation.

    Science.gov (United States)

    van Bergeijk, Stef A; Hernández Javier, Laura; Heyland, Andreas; Manchado, Manuel; Pedro Cañavate, José

    2013-08-01

    Uptake of iodide was studied in the marine microalga Isochrysis sp. (isol. Haines, T.ISO) during short-term incubations with radioactive iodide ((125) I(-) ). Typical inhibitors of the sodium/iodide symporter (NIS) did not inhibit iodide uptake, suggesting that iodide is not taken up through this transport protein, as is the case in most vertebrate animals. Oxidation of iodide was found to be an essential step for its uptake by T.ISO and it seemed likely that hypoiodous acid (HOI) was the form of iodine taken up. Uptake of iodide was inhibited by the addition of thiourea and of other reducing agents, like L-ascorbic acid, L-glutathione and L-cysteine and increased after the addition of oxidized forms of the transition metals Fe and Mn. The simultaneous addition of both hydrogen peroxide (H2 O2 ) and a known iodide-oxidizing myeloperoxidase (MPO) significantly increased iodine uptake, but the addition of H2 O2 or MPO separately, had no effect on uptake. This confirms the observation that iodide is oxidized prior to uptake, but it puts into doubt the involvement of H2 O2 excretion and membrane-bound or extracellular haloperoxidase activity of T.ISO. The increase of iodide uptake by T.ISO upon Fe(III) addition suggests the nonenzymatic oxidation of iodide by Fe(III) in a redox reaction and subsequent influx of HOI. This is the first report on the mechanism of iodide uptake in a marine microalga.

  19. 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

  20. Neutron Detection with Mercuric Iodide

    CERN Document Server

    Bell, Z A

    2003-01-01

    Mercuric iodide is a high-density, high-Z semiconducting material useful for gamma ray detection. This makes it convertible to a thermal neutron detector by covering it with a boron rich material and detecting the 478 keV gamma rays resulting from the sup 1 sup 0 B(n, alpha) sup 7 Li* reaction. However, the 374 barn thermal capture cross section of sup n sup a sup t Hg, makes the detector itself an attractive absorber, and this has been exploited previously. Since previous work indicates that there are no low-energy gamma rays emitted in coincidence with the 368 keV capture gamma from the dominant sup 1 sup 9 sup 9 Hg(n, gamma) sup 2 sup 0 sup 0 Hg reaction, only the 368 keV capture gamma is seen with any efficiency a relatively thin (few mm) detector. In this paper we report preliminary measurements of neutrons via capture reactions in a bare mercuric iodide crystal and a crystal covered in sup 1 sup 0 B-loaded epoxy. The covered detector is an improvement over the bare detector because the presence of both ...

  1. Antimony quantification in Leishmania by electrothermal atomic absorption spectroscopy.

    Science.gov (United States)

    Roberts, W L; Rainey, P M

    1993-05-15

    Tri- and pentavalent antimony were quantified in Leishmania mexicana pifanoi amastigotes and promastigotes by atomic absorption spectroscopy with electrothermal atomization. Leishmania grown in axenic culture were treated with either potassium antimony tartrate [Sb(III)] or sodium stibogluconate [Sb(V)]. The parasites were collected, digested with nitric acid, and subjected to atomic absorption spectroscopy. The method was linear from 0 to 7 ng of antimony. The interassay coefficients of variation were 9.6 and 5.7% (N = 5) for 0.52 and 3.7-ng samples of leishmanial antimony, respectively. The limit of detection was 95 pg of antimony. The assay was used to characterize Sb(III) and Sb(V) influx and efflux kinetics. Influx rates were determined at antimony concentrations that produced a 50% inhibition of growth (IC50). The influx rates of Sb(V) into amastigotes and promastigotes were 4.8 and 12 pg/million cells/h, respectively, at 200 micrograms antimony/ml. The influx rate of Sb(III) into amastigotes was 41 pg/million cells/h at 20 micrograms antimony/ml. Influx of Sb(III) into promastigotes at 1 microgram antimony/ml was rapid and reached a plateau of 175 pg/million cells in 2 h. Efflux of Sb(III) and Sb(V) from amastigotes and promastigotes exhibited biphasic kinetics. The initial (alpha) half-life of Sb(V) efflux was less than 4 min and that of Sb(III) was 1-2 h. The apparent terminal (beta) half-lives ranged from 7 to 14 h.

  2. Predissociation dynamics of lithium iodide

    CERN Document Server

    Schmidt, H; Stienkemeier, F; Bogomolov, A S; Baklanov, A V; Reich, D M; Skomorowski, W; Koch, C P; Mudrich, M

    2015-01-01

    The predissociation dynamics of lithium iodide (LiI) in the first excited A-state is investigated for molecules in the gas phase and embedded in helium nanodroplets, using femtosecond pump-probe photoionization spectroscopy. In the gas phase, the transient Li+ and LiI+ ion signals feature damped oscillations due to the excitation and decay of a vibrational wave packet. Based on high-level ab initio calculations of the electronic structure of LiI and simulations of the wave packet dynamics, the exponential signal decay is found to result from predissociation predominantly at the lowest avoided X-A potential curve crossing, for which we infer a coupling constant V=650(20) reciprocal cm. The lack of a pump-probe delay dependence for the case of LiI embedded in helium nanodroplets indicates fast droplet-induced relaxation of the vibrational excitation.

  3. Predissociation dynamics of lithium iodide

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, H.; Vangerow, J. von; Stienkemeier, F.; Mudrich, M., E-mail: mudrich@physik.uni-freiburg.de [Physikalisches Institut, Universität Freiburg, 79104 Freiburg (Germany); Bogomolov, A. S. [Institute of Chemical Kinetics and Combustion, Novosibirsk 630090 (Russian Federation); Baklanov, A. V. [Institute of Chemical Kinetics and Combustion, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Novosibirsk 630090 (Russian Federation); Reich, D. M.; Skomorowski, W.; Koch, C. P. [Theoretische Physik, Universität Kassel, Heinrich-Plett-Str. 40, 34132 Kassel (Germany)

    2015-01-28

    The predissociation dynamics of lithium iodide (LiI) in the first excited A-state is investigated for molecules in the gas phase and embedded in helium nanodroplets, using femtosecond pump-probe photoionization spectroscopy. In the gas phase, the transient Li{sup +} and LiI{sup +} ion signals feature damped oscillations due to the excitation and decay of a vibrational wave packet. Based on high-level ab initio calculations of the electronic structure of LiI and simulations of the wave packet dynamics, the exponential signal decay is found to result from predissociation predominantly at the lowest avoided X-A potential curve crossing, for which we infer a coupling constant V{sub XA} = 650(20) cm{sup −1}. The lack of a pump-probe delay dependence for the case of LiI embedded in helium nanodroplets indicates fast droplet-induced relaxation of the vibrational excitation.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 40 CFR 440.90 - Applicability; description of the antimony ore subcategory.

    Science.gov (United States)

    2010-07-01

    ... antimony ore subcategory. 440.90 Section 440.90 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ORE MINING AND DRESSING POINT SOURCE CATEGORY Antimony Ore Subcategory § 440.90 Applicability; description of the antimony ore subcategory. The provisions of...

  11. Possible Links between Sickle Cell Crisis and Pentavalent Antimony

    Science.gov (United States)

    Garcerant, Daniel; Rubiano, Luisa; Blanco, Victor; Martinez, Javier; Baker, Nancy C.; Craft, Noah

    2012-01-01

    For over 60 years, pentavalent antimony (Sbv) has been the first-line treatment of leishmaniasis. Sickle cell anemia is a disease caused by a defect in red blood cells, which among other things can cause vasooclusive crisis. We report the case of a 6-year-old child with leishmaniasis who during treatment with meglumine antimoniate developed a sickle cell crisis (SCC). No previous reports describing the relationship between antimonial drugs and sickle cell disease were found. Reviews of both the pathophysiology of SCC and the mechanism of action of Sbv revealed that a common pathway (glutathione) may have resulted in the SCC. ChemoText, a novel database created to predict chemical-protein-disease interactions, was used to perform a more expansive and systematic review that was able to support the association between glutathione, Sbv, and SCC. Although suggestive evidence to support the hypothesis, additional research at the bench would be needed to prove Sbv caused the SCC. PMID:22665619

  12. 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.

  13. Antimony Based III-V Thermophotovoltaic Devices

    Energy Technology Data Exchange (ETDEWEB)

    CA Wang

    2004-06-09

    Antimony-based III-V thermophotovoltaic (TPV) cells are attractive converters for systems with low radiator temperature around 1100 to 1700 K, since these cells potentially can be spectrally matched to the thermal source. Cells under development include GaSb and the lattice-matched GaInAsSb/GaSb and InPAsSb/InAs quaternary systems. GaSb cell technology is the most mature, owing in part to the relative ease in preparation of the binary alloy compared to quaternary GaInAsSb and InPAsSb alloys. Device performance of 0.7-eV GaSb cells exceeds 90% of the practical limit. GaInAsSb TPV cells have been the primary focus of recent research, and cells with energy gap E{sub g} ranging from {approx}0.6 to 0.49 eV have been demonstrated. Quantum efficiency and fill factor approach theoretical limits. Open-circuit voltage factor is as high as 87% of the practical limit for the higher-E{sub g} cells, but degrades to below 80% with decreasing E{sub g} of the alloy, which might be due to Auger recombination. InPAsSb cells are the least studied, and a cell with E{sub g} = 0.45-eV has extended spectral response out to 4.3 {micro}m. This paper briefly reviews the main contributions that have been made for antimonide-based TPV cells, and suggests additional studies for further performance enhancements.

  14. 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%.

  15. Voltammetric determination of copper(II) using antimony film electrodes

    OpenAIRE

    Ashrafi, Amir Mansoor; Husáková, Lenka; Vytřas, Karel

    2012-01-01

    Possibility of determination of Cu(II) at antimony modified carbon paste electrode and its application in determination of trace amount of copper in real sample has been investigated. According to obtained results, it was found that SbF-CPE can be used for these purposes successfully. Both detection limit of 1.45 ppb (evaluated as 3σ) and RSD 4.8 (for 10 ppb Cu and 10 different measurements) were also evaluated. Antimony-based electrodes are environmentally friendly which is their most import...

  16. Simplest Formula of Copper Iodide: A Stoichiometry Experiment.

    Science.gov (United States)

    MacDonald, D. J.

    1983-01-01

    Describes an experiment presented to students as a problem in determining the stoichiometry of "copper iodide" to decide whether it is cuprous iodide or cupric iodide. The experiment illustrates stoichiometry principles, providing experiences with laboratory techniques and numerical computation. Detailed outline (written for student use) is…

  17. Electrochemical reaction rates in a dye sentisised solar cell - the iodide/tri-iodide redox system

    DEFF Research Database (Denmark)

    Bay, Lasse; West, Keld; Winter-Jensen, Bjørn

    2006-01-01

    The electrochemical reaction rate of the redox couple iodide / tri-iodide in acetonitrile is characterised by impedance spectroscopy. Different electrode materials relevant for the function of dye-sensitised solar cells (DSSC) are investigated. Preferably, the reaction with the iodide / tri......-iodide couple should be fast at the counter electrode, i.e. this electrode must have a high catalytic activity towards the redox couple, and the same reaction must be slow on the photo electrode. The catalytic activity is investigated for platinum, poly(3,4-ethylenedioxythiophene) (PEDOT), polypyrrole (PPy......), and polyaniline (PANI) - all deposited onto fluorine doped tin oxide (FTO) glass. Both Pt and PEDOT are found to have sufficiently high catalytic activities for practical use as counter electrode in DSSC. The reaction resistance on FTO and anatase confirmed the beneficial effect of a compact anatase layer on top...

  18. Barium iodide and strontium iodide crystals andd scintillators implementing the same

    Science.gov (United States)

    Payne, Stephen A; Cherepy, Nerine J; Hull, Giulia E; Drobshoff, Alexander D; Burger, Arnold

    2013-11-12

    In one embodiment, a material comprises a crystal comprising strontium iodide providing at least 50,000 photons per MeV. A scintillator radiation detector according to another embodiment includes a scintillator optic comprising europium-doped strontium iodide providing at least 50,000 photons per MeV. A scintillator radiation detector in yet another embodiment includes a scintillator optic comprising SrI.sub.2 and BaI.sub.2, wherein a ratio of SrI.sub.2 to BaI.sub.2 is in a range of between 0:1 A method for manufacturing a crystal suitable for use in a scintillator includes mixing strontium iodide-containing crystals with a source of Eu.sup.2+, heating the mixture above a melting point of the strontium iodide-containing crystals, and cooling the heated mixture near the seed crystal for growing a crystal. Additional materials, systems, and methods are presented.

  19. Methyl Iodide Fumigation of Bacillus anthracis Spores.

    Science.gov (United States)

    Sutton, Mark; Kane, Staci R; Wollard, Jessica R

    2015-09-01

    Fumigation techniques such as chlorine dioxide, vaporous hydrogen peroxide, and paraformaldehyde previously used to decontaminate items, rooms, and buildings following contamination with Bacillus anthracis spores are often incompatible with materials (e.g., porous surfaces, organics, and metals), causing damage or residue. Alternative fumigation with methyl bromide is subject to U.S. and international restrictions due to its ozone-depleting properties. Methyl iodide, however, does not pose a risk to the ozone layer and has previously been demonstrated as a fumigant for fungi, insects, and nematodes. Until now, methyl iodide has not been evaluated against Bacillus anthracis. Sterne strain Bacillus anthracis spores were subjected to methyl iodide fumigation at room temperature and at 550C. Efficacy was measured on a log-scale with a 6-log reduction in CFUs being considered successful compared to the U.S. Environmental Protection Agency biocide standard. Such efficacies were obtained after just one hour at 55 °C and after 12 hours at room temperature. No detrimental effects were observed on glassware, PTFE O-rings, or stainless steel. This is the first reported efficacy of methyl iodide in the reduction of Bacillus anthracis spore contamination at ambient and elevated temperatures.

  20. Potassium iodide capsule treatment of feline sporotrichosis.

    Science.gov (United States)

    Reis, Erica G; Gremião, Isabella D F; Kitada, Amanda A B; Rocha, Raphael F D B; Castro, Verônica S P; Barros, Mônica B L; Menezes, Rodrigo C; Pereira, Sandro A; Schubach, Tânia M P

    2012-06-01

    Sporotrichosis is a mycosis caused by Sporothrix schenckii. The most affected animal is the cat; it has played an important role in the zoonotic transmission of this disease, especially in Rio de Janeiro, Brazil, since 1998. In order to evaluate the treatment of feline sporotrichosis with potassium iodide, an observational cohort was conducted in 48 cats with sporotrichosis at Instituto de Pesquisa Clínica Evandro Chagas, Fiocruz. All cats received potassium iodide capsules, 2.5 mg/kg to 20 mg/kg q24h. The cure rate was 47.9%, treatment failure was 37.5%, treatment abandonment was 10.4% and death was 4.2%. Clinical adverse effects were observed in 52.1% of the cases. Thirteen cats had a mild increase in hepatic transaminase levels during the treatment, six of them presented clinical signs suggestive of hepatotoxicity. Compared to previous studies with itraconazole and iodide in saturated solution, potassium iodide capsules are an alternative for feline sporotrichosis treatment.

  1. Atomic force microscopy of lead iodide crystal surfaces

    Science.gov (United States)

    George, M. A.; Azoulay, M.; Jayatirtha, H. N.; Biao, Y.; Burger, A.; Collins, W. E.; Silberman, E.

    1994-03-01

    Atomic force microscopy (AFM) was used to characterize the surface of lead iodide crystals. The high vapor pressure of lead iodide prohibits the use of traditional high resolution surface study techniques that require high vacuum conditions. AFM was used to image numerous insulating surface in various ambients, with very little sample preparation techniques needed. Freshly cleaved and modified surfaces, including, chemical and vacuum etched, and air aged surfaces, were examined. Both intrinsic and induced defects were imaged with high resolution. The results were compared to a similar AFM study of mercuric iodide surfaces and it was found that, at ambient conditions, lead iodide is significantly more stable than mercuric iodide.

  2. Formulation and optimization of potassium iodide tablets

    OpenAIRE

    Al-Achi, Antoine; Patel, Binit

    2014-01-01

    The use of potassium iodide (KI) as a protective agent against accidental radioactive exposure is well established. In this study, we aimed to prepare a KI tablet formulation using a direct compression method. We utilized Design of Experiment (DoE)/mixture design to define the best formulation with predetermined physical qualities as to its dissolution, hardness, assay, disintegration, and angle of repose. Based on the results from the DoE, the formulation had the following components (%w/w):...

  3. Formulation and optimization of potassium iodide tablets.

    Science.gov (United States)

    Al-Achi, Antoine; Patel, Binit

    2015-01-01

    The use of potassium iodide (KI) as a protective agent against accidental radioactive exposure is well established. In this study, we aimed to prepare a KI tablet formulation using a direct compression method. We utilized Design of Experiment (DoE)/mixture design to define the best formulation with predetermined physical qualities as to its dissolution, hardness, assay, disintegration, and angle of repose. Based on the results from the DoE, the formulation had the following components (%w/w): Avicel 48.70%, silicon dioxide 0.27%, stearic acid (1.00%), magnesium stearate 2.45%, and dicalcium phosphate 18.69%, in addition to potassium iodide 28.89% (130 mg/tablet). This formulation was scaled-up using two tablet presses, a single-punch press and a rotary mini tablet press. The final scaled-up formulation was subjected to a variety of quality control tests, including photo-stability testing. The results indicate that potassium iodide tablets prepared by a rotary mini tablet press had good pharmaceutical characteristics and a shelf-life of 25 days when stored at room temperature protected from light.

  4. Formation of cyanogen iodide by lactoperoxidase.

    Science.gov (United States)

    Schlorke, Denise; Flemmig, Jörg; Birkemeyer, Claudia; Arnhold, Jürgen

    2016-01-01

    The haem protein lactoperoxidase (LPO) is an important component of the anti-microbial immune defence in external secretions and is also applied as preservative in food, oral care and cosmetic products. Upon oxidation of SCN(-) and I(-) by the LPO-hydrogen peroxide system, oxidised species are formed with bacteriostatic and/or bactericidal activity. Here we describe the formation of the inter(pseudo)halogen cyanogen iodide (ICN) by LPO. This product is formed when both, thiocyanate and iodide, are present together in the reaction mixture. Using (13)C nuclear magnetic resonance spectroscopy and gas chromatography-mass spectrometry we could identify this inter(pseudo)halogen after applying iodide in slight excess over thiocyanate. The formation of ICN is based on the reaction of oxidised iodine species with thiocyanate. Further, we could demonstrate that ICN is also formed by the related haem enzyme myeloperoxidase and, in lower amounts, in the enzyme-free system. As I(-) is not competitive for SCN(-) under physiologically relevant conditions, the formation of ICN is not expected in secretions but may be relevant for LPO-containing products.

  5. 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

  6. 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

  7. 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

  8. Cu-catalyzed trifluoromethylation of aryl iodides with trifluoromethylzinc reagent prepared in situ from trifluoromethyl iodide

    Directory of Open Access Journals (Sweden)

    Yuzo Nakamura

    2013-11-01

    Full Text Available The trifluoromethylation of aryl iodides catalyzed by copper(I salt with trifluoromethylzinc reagent prepared in situ from trifluoromethyl iodide and Zn dust was accomplished. The catalytic reactions proceeded under mild reaction conditions, providing the corresponding aromatic trifluoromethylated products in moderate to high yields. The advantage of this method is that additives such as metal fluoride (MF, which are indispensable to activate silyl groups for transmetallation in the corresponding reactions catalyzed by copper salt by using the Ruppert–Prakash reagents (CF3SiR3, are not required.

  9. Pattern formation during electrodeposition of copper-antimony alloys

    Directory of Open Access Journals (Sweden)

    Vasil S. Kostov

    2016-04-01

    Full Text Available Aim of the present study is to establish the conditions of the electrolysis for the preparation of structured and unstressed purple-pink coatings of copper-antimony alloys, including their phase characterization. Also the task of the present investigation is, by changing drastically the metal content in the methanesulfonic electrolyte to find out the conditions of electrolysis where the self-organization of the different phases is expressed by higher-order structures - not only waves but also spirals and targets. The possibility to obtain copper-antimony alloy with up to 80 wt. % Sb from methanesulfonic acid is shown. The deposition rate, morphology and the phase composition of the obtained coatings are established. The phenomena of formation of spatio-temporal structures in this alloy are described.It is determined that the observed structures consist of Cu2Sb and Cu11Sb3 intermetallic phases.

  10. Distribution of liposome-encapsulated antimony in dogs

    Directory of Open Access Journals (Sweden)

    D.A. Schettini

    2003-02-01

    Full Text Available The achievement of complete cure in dogs with visceral leishmaniasis is currently a great challenge, since dogs are the main reservoir for the transmission of visceral leishmaniasis to humans and they respond poorly to conventional treatment with pentavalent antimonials. In order to improve the efficacy of treatment, we developed a novel formulation for meglumine antimoniate based on the encapsulation of this drug in freeze-dried liposomes (LMA. The aim of the present study was to evaluate the biodistribution of antimony (Sb in dogs following a single intravenous bolus injection of LMA. Four healthy male mongrel dogs received LMA at 3.8 mg Sb/kg body weight and were sacrificed 3, 48 and 96 h and 7 days later. Antimony was determined in the blood, liver, spleen and bone marrow. In the bone marrow, the highest Sb concentration was observed at 3 h (2.8 µg/g wet weight whereas in the liver and spleen it was demonstrated at 48 h (43.6 and 102.4 µg/g, respectively. In these organs, Sb concentrations decreased gradually and reached levels of 19.1 µg/g (liver, 28.1 µg/g (spleen and 0.2 µg/g (bone marrow after 7 days. Our data suggest that the critical organ for the treatment with LMA could be the bone marrow, since it has low Sb levels and, presumably, high rates of Sb elimination. A multiple dose treatment with LMA seems to be necessary for complete elimination of parasites from bone marrow in dogs with visceral leishmaniasis.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. Vapor Growth of Mercuric Iodide Tetragonal Prismatic Crystals

    Science.gov (United States)

    2013-03-01

    These steps were followed by immersion in 1% potassium iodide (KI) solution. The apparatus were then cleaned and rinsed thoroughly with deionized (DI...Pergamon Press, 1973. [34] N. Lyakh, “Composition and kinetic characteristics of vapour phase during mercuric iodide growing,” Crystal Res. Technol...DTRA-TR-13-6 Vapor Growth of Mercuric Iodide Tetragonal Prismatic Crystals Approved for public release, distribution is unlimited. March 2013

  16. Synthesis and tribological properties of antimony N, N-diethanoldithiocarbamate

    Institute of Scientific and Technical Information of China (English)

    李丽; 黄可龙; 瞿龙; 舒万艮

    2001-01-01

    Antimony N, N-diethanoldithiocarbamate was synthesized with diethanolamine, antimony trioxide and carbon disulfide. The influences of temperature, reaction time, solvents and their dosages were investigated, and the optimum synthesis conditions were: reaction temperature 15~20 ℃, reaction time 2.5 h, 250 mL CH3OH as solvent and the hot CH3OH as recrystallization solvent. Element analysis, IR, 1HNMR and 13CNMR spectra were used to study its chemical composition and molecular structure. Antimony N, N-diethanol-dithiocarbamate was added in the base oil, and its properties of wear resistance and extreme pressure were studied by FB, FD and WSD. The synthesis product behaves per fectly as wear resistance and extreme pressure additive and its extreme pressure property is superior to its wear resistance property. The mechanism of tribological action was discussed by using XPS and AES spectra, and the reason of good wear resistance and extreme pressure properties is that the synthesis product decompose element C, S and N.

  17. Effect of nitrogen and oxygen on radiolysis of iodide solution

    Energy Technology Data Exchange (ETDEWEB)

    Karasawa, H.; Endo, M. [Hitachi Ltd., Power and Industrial System R+D Divisions, Ibaraki (Japan)

    1996-12-01

    The effect of nitrogen and oxygen on radiolysis of iodide solution was examined. Direct decomposition of nitrogen by {gamma}-radiation produced nitric acid to decrease a water pH. This resulted in the iodine formation in the radiolysis of iodide solution. Hydrogen peroxide was produced by the radiolysis of water containing oxygen. This worked a reducing agent to suppress the formation of iodine in the radiolysis of iodide solution. In the analytical model, fourteen iodine species were considered and reaction scheme consisted in 124 reactions. The analytical model could estimate the oxidation state of iodide ions. (author) 4 figs., 4 refs.

  18. Mercuric Iodide Anticoincidence Shield for Gamma-Ray Spectrometer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to utilize a new detector material, polycrystalline mercuric iodide, for background suppression by active anticoincidence shielding in gamma-ray...

  19. Mercuric Iodide Anticoincidence Shield for Gamma-Ray Spectrometer Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We utilize a new detector material, polycrystalline mercuric iodide, for background suppression by active anticoincidence shielding in gamma-ray spectrometers. Two...

  20. The addition of iodine to tetramethylammonium iodide

    Science.gov (United States)

    Foote, H.W.; Fleischer, M.

    1953-01-01

    The system tetramethylammonium iodide-iodine-toluene has been studied by the solubility method at 6 and at 25??. The compounds (CH3)4NI3, (CH3)4NI5 and (CH3)4NI11 were found to be stable phases at both temperatures. In addition, the compound (CH3)4NI10 was found at 6?? and the compound (CH3)4NI9 at 25??. The dissociation pressures of the compounds at these temperatures were calculated from the solubility data.

  1. Electronic and optical properties of lead iodide

    DEFF Research Database (Denmark)

    Ahuja, R.; Arwin, H.; Ferreira da Silva, A.

    2002-01-01

    The electronic properties and the optical absorption of lead iodide (PbI2) have been investigated experimentally by means of optical absorption and spectroscopic ellipsometry, and theoretically by a full-potential linear muffin-tin-orbital method. PbI2 has been recognized as a very promising...... detector material with a large technological applicability. Its band-gap energy as a function of temperature has also been measured by optical absorption. The temperature dependence has been fitted by two different relations, and a discussion of these fittings is given. ©2002 American Institute of Physics....

  2. Novel mercuric iodide polycrystalline nuclear particles counters

    Energy Technology Data Exchange (ETDEWEB)

    Schieber, M. [Hebrew Univ. of Jerusalem (Israel)]|[Sandia National Lab., Livermore, CA (United States); Zuck, A.; Braiman, M.; Nissenbaum, J. [Hebrew Univ. of Jerusalem (Israel)] [and others

    1996-12-31

    Polycrystalline mercuric iodide nuclear radiation detectors having areas between 0.01 to 100 cm{sup 2} and thicknesses 30 to 600 microns, have been fabricated with single, linear strip and square pixel contact. The large area detectors 10 to 600 cm{sup 2} were produced by industrial ceramic equipment while the smaller ones, about 1 cm{sup 2} area, were produced in the laboratory. The large detectors still had large leakage currents and the production process is being revised. The smaller detectors were tested and their response to lower and higher gamma energy, beta and even 100 GeV muons at CERN will be reported.

  3. LUMINESCENT PROPERTIES OF SILICATE GLASSES WITH CERIUM IONS AND ANTIMONY

    Directory of Open Access Journals (Sweden)

    A. M. Klykova

    2014-05-01

    Full Text Available The paper deals with the results of an experimental study of luminescence excitation spectra and luminescence of silicate glasses containing cerium ions and antimony. The aim of this work was to study the features of the luminescence and the effect of UV irradiation and heat treatment on luminescence and the state of cerium ions and antimony in glass. We investigated glass system Na2O-ZnO-Al2O3-SiO2-NaF-NaBr with additives CeO2 and Sb2O3. Synthesis was carried out in platinum crucibles in the air at 14500C. The samples were polished glass plates with a thickness of 0.5-1 mm. UV irradiation was carried out with a mercury lamp having a wide range of radiation in the spectral range 240-390 nm. It was conducted in a Nabertherm muffle furnaces. Luminescence spectra and excitation spectra were measured using a spectrofluorimeter MPF-44A (PerkinElmer at the room temperature. Measured luminescence spectra were corrected in view of the spectral sensitivity of the photodetector for spectrofluorimeter. Adjustment of the excitation spectra for the spectral dependence of the intensity of the excitation source was not carried out. During the experiments it was found that in silicate glasses Sb3+ ions can exist in two energy states, which corresponds to a different environment with oxygen ions. Heat treatment of these glasses in an oxidizing atmosphere leads to an increase in ion concentration of Sb3+ ions with a greater amount of oxygen in the environment. In glasses containing antimony and cerium ions, ultraviolet irradiation causes a change in the valence of cerium ions and antimony, which is accompanied by luminescence quenching. Subsequent heat treatment of glass leads to the inverse processes and restore luminescence excitation spectra. The study of fluorescent properties of silicate glasses with cerium and antimony ions led to the conclusion of the practical significance of this work. Promising multifunctional materials can be created on the basis of

  4. Production of Molecular Iodine and Tri-iodide in the Frozen Solution of Iodide: Implication for Polar Atmosphere.

    Science.gov (United States)

    Kim, Kitae; Yabushita, Akihiro; Okumura, Masanori; Saiz-Lopez, Alfonso; Cuevas, Carlos A; Blaszczak-Boxe, Christopher S; Min, Dae Wi; Yoon, Ho-Il; Choi, Wonyong

    2016-02-01

    The chemistry of reactive halogens in the polar atmosphere plays important roles in ozone and mercury depletion events, oxidizing capacity, and dimethylsulfide oxidation to form cloud-condensation nuclei. Among halogen species, the sources and emission mechanisms of inorganic iodine compounds in the polar boundary layer remain unknown. Here, we demonstrate that the production of tri-iodide (I3(-)) via iodide oxidation, which is negligible in aqueous solution, is significantly accelerated in frozen solution, both in the presence and the absence of solar irradiation. Field experiments carried out in the Antarctic region (King George Island, 62°13'S, 58°47'W) also showed that the generation of tri-iodide via solar photo-oxidation was enhanced when iodide was added to various ice media. The emission of gaseous I2 from the irradiated frozen solution of iodide to the gas phase was detected by using cavity ring-down spectroscopy, which was observed both in the frozen state at 253 K and after thawing the ice at 298 K. The accelerated (photo-)oxidation of iodide and the subsequent formation of tri-iodide and I2 in ice appear to be related with the freeze concentration of iodide and dissolved O2 trapped in the ice crystal grain boundaries. We propose that an accelerated abiotic transformation of iodide to gaseous I2 in ice media provides a previously unrecognized formation pathway of active iodine species in the polar atmosphere.

  5. 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.

  6. Phase 2 Methyl Iodide Deep-Bed Adsorption Tests

    Energy Technology Data Exchange (ETDEWEB)

    Soelberg, Nick [Idaho National Lab. (INL), Idaho Falls, ID (United States); Watson, Tony [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-09-01

    Nuclear fission produces fission products (FPs) and activation products, including iodine-129, which could evolve into used fuel reprocessing facility off-gas systems, and could require off-gas control to limit air emissions to levels within acceptable emission limits. Research, demonstrations, and some reprocessing plant experience have indicated that diatomic iodine can be captured with efficiencies high enough to meet regulatory requirements. Research on the capture of organic iodides has also been performed, but to a lesser extent. Several questions remain open regarding the capture of iodine bound in organic compounds. Deep-bed methyl iodide adsorption testing has progressed according to a multi-laboratory methyl iodide adsorption test plan. This report summarizes the second phase of methyl iodide adsorption work performed according to this test plan using the deep-bed iodine adsorption test system at the Idaho National Laboratory (INL), performed during the second half of Fiscal Year (FY) 2014. Test results continue to show that methyl iodide adsorption using AgZ can achieve total iodine decontamination factors (DFs, ratios of uncontrolled and controlled total iodine levels) above 1,000, until breakthrough occurred. However, mass transfer zone depths are deeper for methyl iodide adsorption compared to diatomic iodine (I2) adsorption. Methyl iodide DFs for the Ag Aerogel test adsorption efficiencies were less than 1,000, and the methyl iodide mass transfer zone depth exceeded 8 inches. Additional deep-bed testing and analyses are recommended to (a) expand the data base for methyl iodide adsorption under various conditions specified in the methyl iodide test plan, and (b) provide more data for evaluating organic iodide reactions and reaction byproducts for different potential adsorption conditions.

  7. Kinetic Isotope Effects in the Reduction of Methyl Iodide

    DEFF Research Database (Denmark)

    Holm, Torkil

    1999-01-01

    a-Deuterium kinetic isotope effects (KIE's) have been determined for the reaction of methyl iodide with a series of reducing agents. Reagents which transfer hydride ion in an SN2 reaction show small inverse or small normal KIE's. Reagents which transfer an electron to methyl iodide to produce...

  8. 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.

  9. Alkaline sulfide pretreatment of an antimonial refractory Au-Ag ore for improved cyanidation

    Science.gov (United States)

    Alp, Ibrahim; Celep, Oktay; Deveci, Haci

    2010-11-01

    This paper presents the alkaline sulfide pretreatment of an antimonial refractory gold and silver ore. In the ore, gold occurs mainly as gold-silver alloys and as associated with quartz and framboidal pyrite grains, and, to a small extent, as the inclusions within antimonial sulfides. Silver is present extensively as antimonial sulfides such as andorite. Alkaline sulfide pretreatment was shown to allow the decomposition of the antimonial sulfide minerals (up to 98% Sb removal) and to remarkably improve the amenability of gold (e.g., from silver (e.g., from leaching. An increase in reagent concentration (1-4 mol/L Na2S or NaOH) and temperature (20-80°C), and a decrease in particle size seem to produce an enhancing effect on metal extraction. These findings suggest that alkaline sulfide leaching can be suitably used as a chemical pretreatment method prior to the conventional cyanidation for antimonial refractory gold and silver ores.

  10. 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

  11. 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.

  12. Silver iodide sodalite for 129I immobilisation

    Science.gov (United States)

    Vance, E. R.; Gregg, D. J.; Grant, C.; Stopic, A.; Maddrell, E. R.

    2016-11-01

    Silver iodide sodalite was initially synthesised as a fine-grained major phase in a nominally stoichiometric composition following hot isostatic pressing at 850 °C with 100 MPa and its composition, Ag4Al3Si3O12I, was approximately verified by scanning electron microscopy. An alternative preparative method yielded a more dense and stoichiometric AgI sodalite on sintering and HIPing. As found for AgI, the I is released from AgI sodalite much more readily in reducing water than in ordinary water. Thus in normal PCT-B tests, the I release was <0.3 g/L in water, but it was ∼70 g/L under highly reducing conditions. This is an important point with regard to can material if HIPing is used for consolidation.

  13. Novel mercuric iodide polycrystalline nuclear particle counters

    Energy Technology Data Exchange (ETDEWEB)

    Schieber, M. [Hebrew Univ. of Jerusalem (Israel)]|[Sandia National Labs., Livermore, CA (United States); Zuck, A.; Braiman, M.; Nissenbaum, J. [Hebrew Univ. of Jerusalem (Israel); Turchetta, R.; Dulinski, W.; Husson, D.; Riester, J.L. [LEPSI, Strasbourg (France)

    1997-12-01

    Polycrystalline mercuric iodide nuclear radiation detectors have been produced in a novel technology. Unlike the normal single-crystal technology, there is no intrinsic limit to the surface on which these detectors can be produced. Detectors with areas up to about 1.5 cm{sup 2}, thicknesses from 30 to 600 {micro}m, and with single electrodes as well as microstrip and pixel contacts have been fabricated and successfully tested with photons in the range of 40--660 keV, {beta} particle`s emitted from a Sr-Y source, and high energy (100 GeV) muons. Results on both charge collection and counting efficiency are reported as well as some very preliminary imaging results. The experimental results on charge collection have been compared with simulation, and a combined {mu}{tau} product 10{sup {minus}7} cm{sup 2}/V for electrons has been estimated.

  14. Ferroelastic Fingerprints in Methylammonium Lead Iodide Perovskite

    KAUST Repository

    Hermes, Ilka M.

    2016-02-12

    Methylammonium lead iodide (MAPbI3) perovskite materials show an outstanding performance in photovoltaic devices. However, certain material properties, especially the possible ferroic behavior, remain unclear. We observed distinct nanoscale periodic domains in the piezoresponse of MAPbI3(Cl) grains. The structure and the orientation of these striped domains indicate ferroelasticity as their origin. By correlating vertical and lateral piezoresponse force microscopy experiments performed at different sample orientations with x-ray diffraction, the preferred domain orientation was suggested to be the a1-a2-phase. The observation of these ferroelastic fingerprints appears to strongly depend on the film texture and thus the preparation route. The formation of the ferroelastic twin domains could be induced by internal strain during the cubic-tetragonal phase transition.

  15. Conserved charged amino acid residues in the extracellular region of sodium/iodide symporter are critical for iodide transport activity

    Directory of Open Access Journals (Sweden)

    Liang Ji-An

    2010-11-01

    Full Text Available Abstract Background Sodium/iodide symporter (NIS mediates the active transport and accumulation of iodide from the blood into the thyroid gland. His-226 located in the extracellular region of NIS has been demonstrated to be critical for iodide transport in our previous study. The conserved charged amino acid residues in the extracellular region of NIS were therefore characterized in this study. Methods Fourteen charged residues (Arg-9, Glu-79, Arg-82, Lys-86, Asp-163, His-226, Arg-228, Asp-233, Asp-237, Arg-239, Arg-241, Asp-311, Asp-322, and Asp-331 were replaced by alanine. Iodide uptake abilities of mutants were evaluated by steady-state and kinetic analysis. The three-dimensional comparative protein structure of NIS was further modeled using sodium/glucose transporter as the reference protein. Results All the NIS mutants were expressed normally in the cells and targeted correctly to the plasma membrane. However, these mutants, except R9A, displayed severe defects on the iodide uptake. Further kinetic analysis revealed that mutations at conserved positively charged amino acid residues in the extracellular region of NIS led to decrease NIS-mediated iodide uptake activity by reducing the maximal rate of iodide transport, while mutations at conserved negatively charged residues led to decrease iodide transport by increasing dissociation between NIS mutants and iodide. Conclusions This is the first report characterizing thoroughly the functional significance of conserved charged amino acid residues in the extracellular region of NIS. Our data suggested that conserved charged amino acid residues, except Arg-9, in the extracellular region of NIS were critical for iodide transport.

  16. Barium iodide and strontium iodide crystals and scintillators implementing the same

    Energy Technology Data Exchange (ETDEWEB)

    Payne, Stephen A.; Cherepy, Nerine J.; Hull, Giulia E.; Drobshoff, Alexander D.; Burger, Arnold

    2016-11-29

    In one embodiment, a material comprises a crystal comprising strontium iodide providing at least 50,000 photons per MeV, where the strontium iodide material is characterized by a volume not less than 1 cm.sup.3. In another embodiment, a scintillator optic includes europium-doped strontium iodide providing at least 50,000 photons per MeV, where the europium in the crystal is primarily Eu.sup.2+, and the europium is present in an amount greater than about 1.6%. A scintillator radiation detector in yet another embodiment includes a scintillator optic comprising SrI.sub.2 and BaI.sub.2, where a ratio of SrI.sub.2 to BaI.sub.2 is in a range of between 0:1 and 1.0, the scintillator optic is a crystal that provides at least 50,000 scintillation photons per MeV and energy resolution of less than about 5% at 662 keV, and the crystal has a volume of 1 cm.sup.3 or more; the scintillator optic contains more than about 2% europium.

  17. 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)

  18. 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.

  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. 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.

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

    Science.gov (United States)

    Salihoglu, Güray

    2014-11-01

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

  2. 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.

  3. 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.

  4. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-07-30

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

  6. Expression of the human sodium/iodide symporter (hNIS) in xenotransplanted human thyroid carcinoma

    NARCIS (Netherlands)

    Smit, J.W.A.; Schröder - van der Elst, J.P.; Karperien, M.; Que, I.; Romijn, J.A.; Heide, van der D.

    2001-01-01

    The uptake of iodide in thyroid epithelial cells is mediated by the sodium/iodide symporter (NIS). The uptake of iodide is of vital importance for thyroid physiology and is a prerequisite for radioiodine therapy in thyroid cancer. Loss of iodide uptake due to diminished expression of the human NIS (

  7. Separation and Concentration of Indium from Leaching Solution Containing Indium, Antimony and Iron Ions

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Processing conditions of effectively separating indium from the leaching solution of a smelting antimony slag were studied. For the leaching solution containing indium and antimony and iron ions, indium was separated by extracting with HDEHP-kerosine solution, washing antimony and iron ions with oxalic acid solution and stripping indium with a dilute solution of hydrochloric acid. InCl3 solution with purity above 90% is obtained. Indium can be enriched through a circulation of stripping with a dilute HCl solution. The concentration of InCl3 solution is about 25~30 g/L.

  8. 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.

  9. Improved Stability of Mercuric Iodide Detectors for Anticoincidence Shields Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to utilize guard ring electrode structures and a new film growth technique to create improved polycrystalline mercuric iodide detectors for background...

  10. 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

  11. Prevention of organic iodide formation in BWR`s

    Energy Technology Data Exchange (ETDEWEB)

    Karjunen, T. [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland); Laitinen, T.; Piippo, J.; Sirkiae, P. [VTT Manufacturing Technology (Finland)

    1996-12-01

    During an accident, many different forms of iodine may emerge. Organic iodides, such as methyl iodide and ethyl iodide, are relatively volatile, and thus their appearance leads to increased concentration of gaseous iodine. Since organic iodides are also relatively immune to most accident mitigation measures, such as sprays and filters, they can affect the accident source term significantly even when only a small portion of iodine is in organic form. Formation of organic iodides may not be limited by the amount of organic substances available. Excessive amounts of methane can be produced, for example, during oxidation of boron carbide, which is used in BWR`s as a neutron absorber material. Another important source is cable insulation. In a BWR, a large quantity of cables is placed below the pressure vessel. Thus a large quantity of pyrolyse gases will be produced, should the vessel fail. Organic iodides can be formed as a result of many different reactions, but at least in certain conditions the main reaction takes place between an organic radical produced by radiolysis and elemental iodine. A necessary requirement for prevention of organic iodide production is therefore that the pH in the containment water pools is kept high enough to eliminate formation of elemental iodine. In a typical BWR the suppression pool water is usually unbuffered. As a result, the pH may be dominated by chemicals introduced during an accident. If no system for adding basic chemicals is operable, the main factor affecting pool water pH may be hydrochloric acid released during cable degradation. Should this occur, the conditions could be very favorable for production of elemental iodine and, consequently, formation of organic iodides. Although high pH is necessary for iodine retention, it could have also adverse effects. High pH may, for example, accelerate corrosion of containment materials and alter the characteristics of the solid corrosion products. (author) 6 figs., 1 tab., 13 refs.

  12. 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

  13. 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

  14. Chloride, bromide and iodide scintillators with europium

    Science.gov (United States)

    Zhuravleva, Mariya; Yang, Kan

    2016-09-27

    A halide scintillator material is disclosed where the halide may comprise chloride, bromide or iodide. The material is single-crystalline and has a composition of the general formula ABX.sub.3 where A is an alkali, B is an alkali earth and X is a halide which general composition was investigated. In particular, crystals of the formula ACa.sub.1-yEu.sub.yI.sub.3 where A=K, Rb and Cs were formed as well as crystals of the formula CsA.sub.1-yEu.sub.yX.sub.3 (where A=Ca, Sr, Ba, or a combination thereof and X=Cl, Br or I or a combination thereof) with divalent Europium doping where 0.ltoreq.y.ltoreq.1, and more particularly Eu doping has been studied at one to ten mol %. The disclosed scintillator materials are suitable for making scintillation detectors used in applications such as medical imaging and homeland security.

  15. 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.

  16. Electrochemical reaction rates in a dye-sensitised solar cell - the iodide/tri-iodide redox system

    DEFF Research Database (Denmark)

    Bay, L.; West, K.; Winther-Jensen, B.

    2006-01-01

    The electrochemical reaction rate of the redox couple iodide/tri-iodide in acetonitrile is characterised by impedance spectroscopy. Different electrode materials relevant for the function of dye-sensitised solar cells (DSSC) are investigated. Preferably, the reaction with the iodide....../tri-iodide couple should be fast at the counter electrode, i.e. this electrode must have a high catalytic activity towards the redox couple, and the same reaction must be slow on the photo electrode. The catalytic activity is investigated for platinum, poly(3,4-ethylenedioxythiophene) (PEDOT), polypyrrole (PPy......), and polyaniline (PANI)-all deposited onto fluorine-doped tin oxide (FTO) glass. Both Pt and PEDOT are found to have sufficiently high catalytic activities for practical use as counter electrodes in DSSC. The reaction resistance on FTO and anatase confirmed the beneficial effect of a compact anatase layer on top...

  17. 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.

  18. 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.

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

    Directory of Open Access Journals (Sweden)

    Silvia Mancarella

    2016-08-01

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

  20. Magnesium-antimony liquid metal battery for stationary energy storage.

    Science.gov (United States)

    Bradwell, David J; Kim, Hojong; Sirk, Aislinn H C; Sadoway, Donald R

    2012-02-01

    Batteries are an attractive option for grid-scale energy storage applications because of their small footprint and flexible siting. A high-temperature (700 °C) magnesium-antimony (Mg||Sb) liquid metal battery comprising a negative electrode of Mg, a molten salt electrolyte (MgCl(2)-KCl-NaCl), and a positive electrode of Sb is proposed and characterized. Because of the immiscibility of the contiguous salt and metal phases, they stratify by density into three distinct layers. Cells were cycled at rates ranging from 50 to 200 mA/cm(2) and demonstrated up to 69% DC-DC energy efficiency. The self-segregating nature of the battery components and the use of low-cost materials results in a promising technology for stationary energy storage applications.

  1. A novel quasi-one-dimensional topological insulator in bismuth iodide β-Bi4I4

    Science.gov (United States)

    Autès, Gabriel; Isaeva, Anna; Moreschini, Luca; Johannsen, Jens C.; Pisoni, Andrea; Mori, Ryo; Zhang, Wentao; Filatova, Taisia G.; Kuznetsov, Alexey N.; Forró, László; van den Broek, Wouter; Kim, Yeongkwan; Kim, Keun Su; Lanzara, Alessandra; Denlinger, Jonathan D.; Rotenberg, Eli; Bostwick, Aaron; Grioni, Marco; Yazyev, Oleg V.

    2016-02-01

    Recent progress in the field of topological states of matter has largely been initiated by the discovery of bismuth and antimony chalcogenide bulk topological insulators (TIs; refs ,,,), followed by closely related ternary compounds and predictions of several weak TIs (refs ,,). However, both the conceptual richness of Z2 classification of TIs as well as their structural and compositional diversity are far from being fully exploited. Here, a new Z2 topological insulator is theoretically predicted and experimentally confirmed in the β-phase of quasi-one-dimensional bismuth iodide Bi4I4. The electronic structure of β-Bi4I4, characterized by Z2 invariants (1;110), is in proximity of both the weak TI phase (0;001) and the trivial insulator phase (0;000). Our angle-resolved photoemission spectroscopy measurements performed on the (001) surface reveal a highly anisotropic band-crossing feature located at the point of the surface Brillouin zone and showing no dispersion with the photon energy, thus being fully consistent with the theoretical prediction.

  2. 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.

  3. 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”.

  4. 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.

  5. Iodide kinetics and experimental I-131 therapy in a xenotransplanted human sodium-iodide symporter-transfected human follicular thyroid carcinoma cell line

    NARCIS (Netherlands)

    Smit, J.W.A.; Elst, van der J.P.; Karperien, M.; Que, I.; Stokkel, M.; Heide, van der D.; Romijn, J.A.

    2002-01-01

    Uptake of iodide is a prerequisite for radioiodide therapy in thyroid cancer. However, loss of iodide uptake is frequently observed in metastasized thyroid cancer, which may be explained by diminished expression of the human sodium-iodide symporter (hNIS). We studied whether transfection of hNIS int

  6. Molecular imaging using sodium iodide symporter (NIS)

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Je Yoel [School of Dentistry, Kyungpook National Univ., Daegu (Korea, Republic of)

    2004-04-01

    Radioiodide uptake in thyroid follicular epithelial cells, mediated by a plasma membrane transporter, sodium iodide symporter (NIS), provides a first step mechanism for thyroid cancer detection by radioiodide injection and effective radioiodide treatment for patients with invasive, recurrent, and/or metastatic thyroid cancers after total thyroidectomy. NIS gene transfer to tumor cells may significantly and specifically enhance internal radioactive accumulation of tumors following radioiodide administration, and result in better tumor control. NIS gene transfers have been successfully performed in a variety of tumor animal models by either plasmid-mediated transfection or virus (adenovirus or retrovirus)-mediated gene delivery. These animal models include nude mice xenografted with human melanoma, glioma, breast cancer of prostate cancer, rats with subcutaneous thyroid tumor implantation, as well as the rat intracranial glioma model. In these animal models, non-invasive imaging of in vivo tumors by gamma camera scintigraphy after radioiodide or technetium injection has been performed successfully, suggesting that the NIS can serve as an imaging reporter gene for gene therapy trials. In addition, the tumor killing effects of I-131, ReO4-188 and At-211 after NIS gene transfer have been demonstrated in in vitro clonogenic assays and in vivo radioiodide therapy studies, suggesting that NIS gene can also serve as a therapeutic requires a more efficient and specific system of gene delivery with better retention of radioiodide in tumor. Results thus far are, however, promising, and suggest that NIS gene transfer followed by radioiodide treatment will allow non-invasive in vivo imaging to assess the outcome of gene therapy and provide a therapeutic strategy for a variety of human diseases.

  7. Evaluation of mercuric iodide ceramic semiconductor detectors

    Energy Technology Data Exchange (ETDEWEB)

    Schieber, M.; Zuck, A.; Braiman, M.; Nissenbaum, J. [Hebrew Univ., Jerusalem (Israel); Turchetta, R.; Dulinski, W.; Husson, D.; Riester, J.L. [LEPSI (ULP/IN2P3), Strasbourg (France)

    1998-02-01

    Mercuric iodide ceramic radiation detectors, which can act as nuclear particle counters, have been fabricated with single continuos electrical contacts and with linear strip contacts. They have been tested with different kinds of {gamma} and {beta} sources as well as in a high energy beam at CERN. The detectors were also successfully tested for radiation hardness with irradiation of 5*10{sup 14} neutrons/cm{sup 2}. The ratio of detected photons over the number of absorbed photons has been measured with {gamma} sources of different energies, and it ranges from 20% at 44 keV up to about 30% at 660 keV. An absolute efficiency of 70% has been measured for a 350 {mu}m thick detector for {beta} particles emitted by a {sup 90}Sr source. Charge collection efficiency, defined as the amount of charge induced on the electrodes by a mminimum ionizing particle (MIP) traversing the detector, has been measured in two samples. The average collected charge fits well with a linear curve with slope of 35 electrons/(kV/cm) per 100 {mu}m. This result is well described by a dynamic device simulation, where the free carrier mean lifetime is used as a free parameter, adjusted to a value of 1.5 ns, i.e. about 1/100 of the corresponding lifetime in single crystal HgI{sub 2} detectors. The response to MIP has also been studied with a high energy (100 GeV) muon beam in CERN. A preliminary beam profile is presented while a more detailed analysis is still in progress and will be presented elsewhere. These results together with the low cost of the material make ceramic HgI{sub 2} detectors excellent candidates for large area particle tracking and imaging applications, even in a radiation harsh environment. (orig.). 14 refs.

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

    OpenAIRE

    Zhouling Wang; Yu Hu; Wei Li; Guanggen Zeng; Lianghuan Feng; Jingquan Zhang; Lili Wu; Jingjing Gao

    2014-01-01

    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 high...

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

    Science.gov (United States)

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

    2016-01-01

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

  10. Macrosegregation during Plane Front Solidification of Cesium Iodide wt Percent Thallium Iodide Alloy

    Science.gov (United States)

    Sidawi, Ibrahim M. S.

    Macrosegregation produced during directional solidification of CsI-1 wt% TlI by vertical Bridgman technique has been examined in crucibles of varying diameter, from 0.5 to 2.0 cm. Phase diagram and temperature dependence of the thermal conductivity have been determined. The experimentally observed liquid-solid interface shape and the fluid flow behavior have been compared with that computed from the commercially available code FIDAP. Thallium iodide content of the alloy was observed to increase along the length of the directionally solidified specimens, resulting in continuously decreasing light output. The experimentally observed solutal distribution agrees with predictions from the boundary layer model of Favier. The observed macrosegregation behavior suggests that there is a significant convection in the melt even in the smallest crucible diameter of 0.5 cm.

  11. Standard free energy of formation of iron iodide

    Science.gov (United States)

    Khandkar, A.; Tare, V. B.; Wagner, J. B., Jr.

    1983-01-01

    An experiment is reported where silver iodide is used to determine the standard free energy of formation of iron iodide. By using silver iodide as a solid electrolyte, a galvanic cell, Ag/AgI/Fe-FeI2, is formulated. The standard free energy of formation of AgI is known, and hence it is possible to estimate the standard free energy of formation of FeI2 by measuring the open-circuit emf of the above cell as a function of temperature. The free standard energy of formation of FeI2 determined by this method is -38784 + 24.165T cal/mol. It is estimated that the maximum error associated with this method is plus or minus 2500 cal/mol.

  12. Phase 1 Methyl Iodide Deep-Bed Adsorption Tests

    Energy Technology Data Exchange (ETDEWEB)

    Soelberg, Nick [Idaho National Lab. (INL), Idaho Falls, ID (United States); Watson, Tony [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-08-22

    Nuclear fission results in the production of fission products (FPs) and activation products including iodine-129, which could evolve into used fuel reprocessing facility off-gas systems, and could require off-gas control to limit air emissions to levels within acceptable emission limits. Research, demonstrations, and some reprocessing plant experience have indicated that diatomic iodine can be captured with efficiencies high enough to meet regulatory requirements. Research on the capture of organic iodides has also been performed, but to a lesser extent [Jubin 2012b]. Several questions remain open regarding the capture of iodine bound in organic compounds. Deep-bed methyl iodide adsorption testing has progressed according to a multi-laboratory methyl iodide adsorption test plan. This report summarizes the first phase of methyl iodide adsorption work performed according to this test plan using the deep-bed iodine adsorption test system at the Idaho National Laboratory (INL), performed during Fiscal Year (FY) 2013 and early FY-2014. Testing has been performed to address questions posed in the test plan, and followed the testing outline in the test plan. Tests established detection limits, developed procedures for sample analysis with minimal analytical interferences, and confirmed earlier results that show that the methyl iodide reacts when in contact with the AgZ sorbent, and not significantly in the gas flow upstream of the sorbent. The reaction(s) enable separation of the iodine from the organic moiety, so that the iodine can chemisorb onto the sorbent. The organic moiety can form other compounds, some of which are organic compounds that are detected and can be tentatively identified using GC-FID and GCMS. Test results also show that other gas constituents (NOx and/or H2O) can affect the methyl iodide reactions. With NOx and H2O present in the gas stream, the majority of uncaptured iodine exiting iodine-laden sorbent beds is in the form of I2 or HI, species that

  13. 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.

  14. Ion-exchange separation of radioiodine and its application to production of {sup 124}I by alpha particle induced reactions on antimony

    Energy Technology Data Exchange (ETDEWEB)

    Shuza Uddin, Md. [Forschungszentrum Juelich (Germany). Inst. fuer Neurowissenschaften und Medizin, INM-5: Nuklearchemie; Atomic Energy Research Establishment, Inst. of Nuclear Science and Technology, Dhaka (Bangladesh); Qaim, Seyed M.; Spahn, Ingo; Spellerberg, Stefan; Scholten, Bernhard; Coenen, Heinz H. [Forschungszentrum Juelich (Germany). Inst. fuer Neurowissenschaften und Medizin, INM-5: Nuklearchemie; Hermanne, Alex [Vrije Univ. Brussel (Belgium). Cyclotron Lab.; Hossain, Syed Mohammod [Atomic Energy Research Establishment, Inst. of Nuclear Science and Technology, Dhaka (Bangladesh)

    2015-07-01

    The basic parameters related to radiochemical separation of iodine from tellurium and antimony by anion-exchange chromatography using the resin Amberlyst A26 were studied. The separation yield of {sup 124}I amounted to 96% and the decontamination factor from {sup 121}Te and {sup 122}Sb was > 10{sup 4}. The method was applied to the production of {sup 124}I via the {sup 123}Sb(α, 3n) reaction. In an irradiation of 110 mg of {sup nat}Sb{sub 2}O{sub 3} (thickness ∝0.08 g/cm{sup 2}) with 38 MeV α-particles at 1.2 μA beam current for 4 h, corresponding to the beam energy range of E{sub α} = 37 → 27 MeV, the batch yield of {sup 124}I obtained was 12.42 MBq and the {sup 125}I and {sup 126}I impurities amounted to 3.8% and 0.7%, respectively. The experimental batch yield of {sup 124}I amounted to 80% of the theoretically calculated value but the level of the radionuclidic impurities were in agreement with the theoretical values. About 96% of the radioiodine was in the form of iodide and the inactive impurities (Te, Sb, Sn) were below the permissible level. Due to the relatively high level of radionuclidic impurity the {sup 124}I produced would possibly be useful only for restricted local consumption or for animal experiments.

  15. Low energy background in mercuric iodide X-ray spectrometers

    Energy Technology Data Exchange (ETDEWEB)

    Bao, X.J. [TN Technol., Inc., Round Rock, TX (United States). Dept. of Anal. Instrum.; Natarajan, M. [TN Technol., Inc., Round Rock, TX (United States). Dept. of Anal. Instrum.; Henderson, J. [TN Technol., Inc., Round Rock, TX (United States). Dept. of Anal. Instrum.

    1996-10-01

    The origins of the continuous background (window effect or dead layer) in mercuric iodide X-ray spectrometers are investigated. It is found that photo-electron escape and carrier diffusion are the dominant mechanisms of incomplete charge collection in the energy range of interest (from 3-60 keV). X-ray spectra measurements, computer calculation and photo-response measurements are presented in support of the proposed model. Many observations of detector behavior made in the manufacturing and application of mercuric iodide X-ray detectors can be explained by this model. (orig.).

  16. Enhanced Olefin Cross Metathesis Reactions: The Copper Iodide Effect

    Science.gov (United States)

    Voigtritter, Karl; Ghorai, Subir

    2011-01-01

    Copper iodide has been shown to be an effective co-catalyst for the olefin cross metathesis reaction. In particular, it has both a catalyst stabilizing effect due to iodide ion, as well as copper(I)-based phosphine-scavenging properties that apply to use of the Grubbs-2 catalyst. A variety of Michael acceptors and olefinic partners can be cross-coupled under mild conditions in refluxing diethyl ether that avoid chlorinated solvents. This effect has also been applied to chemistry in water at room temperature using the new surfactant TPGS-750-M. PMID:21528868

  17. DBU-Promoted Trifluoromethylation of Aryl Iodides with Difluoromethyltriphenylphosphonium Bromide

    Institute of Scientific and Technical Information of China (English)

    Yun Wei; Liuying Yu; Jinhong Lin; Xing Zheng; Jichang Xiao

    2016-01-01

    DBU-promoted trifluoromethylation of aryl iodides with difluoromethyltriphenylphosphonium bromide (DFPB) in the presence of copper source is described.In this transformation,DBU not only acts as base to deprotonate the difluoromethyl group in DFPB to generate difluoromethylene phosphonium ylide Ph3P+CF2,but also converts the difluorocarbene generated from ylide Ph3P+CF2 into trifluoromethyl anion,finally resulting in the trifluoromethylation of aryl iodides.The reactions proceeded smoothly to afford expected products in moderate to good yields.

  18. Mercuric iodide dosimeter response to high energy electron beams

    Energy Technology Data Exchange (ETDEWEB)

    Loewinger, E.; Nissenbaum, J.; Schieber, M.M.

    1988-01-01

    Mercuric iodide solid state dosimeter response to high energy electron beams of up to 35 MeV is reported. High sensitivity of up to 1.5 V/cGy was observed with a 200 V external bias, as well as several mV/cGy, with no external bias for small volume (approx. 10 mm/sup 3/) detectors. The physical characteristics of the detector response are discussed, showing the feasibility of mercuric iodide as a reliable dosimeter for high energy electron beams.

  19. 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.

  20. 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 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.

  1. Determination of antimony by using tungsten trap atomic absorption spectrometry

    Science.gov (United States)

    Titretir, Serap; Kendüzler, Erdal; Arslan, Yasin; Kula, İbrahim; Bakırdere, Sezgin; Ataman, O. Yavuz.

    2008-08-01

    An electrically heated tungsten coil was used as a trap in the determination of antimony. The technique consists of three steps. Initially, SbH 3 is formed by hydride generation procedure; then the analyte species in vapor form are transported to W-coil trap heated at 370 °C. Following the preconcentration step, the trap is heated to 895 °C; analyte species are revolatilized and transported to the flame-heated quartz atom cell where atomization and the formation of signal take place. The experimental parameters were optimized both for trap and no-trap studies. The most important experimental parameters are concentrations of HCl and NaBH 4 solutions, H 2 and Ar gas flow rates, and collection and revolatilization temperatures of W-coil. Accuracy was tested using a certified reference material, waste water EU-L-1. Limit of detection for the system is 16 ng l - 1 using a sample of 36 ml collected in 4.0 min. Enhancement factor in sensitivity was 17.

  2. Determination of antimony by using tungsten trap atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Titretir, Serap [Department of Chemistry, Inoenue University, 44065 Malatya (Turkey); Kenduezler, Erdal [Department of Primary Education, Faculty of Education, Ahi Evran University, 40100 Kirsehir (Turkey); Arslan, Yasin [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey); Department of Chemistry, Atatuerk University, 25240 Erzurum (Turkey); Kula, Ibrahim [Department of Chemistry, Mugla University, 48000 Mugla (Turkey); Bakirdere, Sezgin [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey); Department of Chemistry, Zonguldak Karaelmas University, 67100 Zonguldak (Turkey); Ataman, O. Yavuz. [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey)], E-mail: ataman@metu.edu.tr

    2008-08-15

    An electrically heated tungsten coil was used as a trap in the determination of antimony. The technique consists of three steps. Initially, SbH{sub 3} is formed by hydride generation procedure; then the analyte species in vapor form are transported to W-coil trap heated at 370 deg. C. Following the preconcentration step, the trap is heated to 895 deg. C; analyte species are revolatilized and transported to the flame-heated quartz atom cell where atomization and the formation of signal take place. The experimental parameters were optimized both for trap and no-trap studies. The most important experimental parameters are concentrations of HCl and NaBH{sub 4} solutions, H{sub 2} and Ar gas flow rates, and collection and revolatilization temperatures of W-coil. Accuracy was tested using a certified reference material, waste water EU-L-1. Limit of detection for the system is 16 ng l{sup -1} using a sample of 36 ml collected in 4.0 min. Enhancement factor in sensitivity was 17.

  3. 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.

  4. Mitochondrial Proteomics of Antimony and Miltefosine Resistant Leishmania infantum

    Directory of Open Access Journals (Sweden)

    Isabel M. Vincent

    2015-10-01

    Full Text Available Antimony (SbIII and miltefosine (MIL are important drugs for the treatment of Leishmania parasite infections. The mitochondrion is likely to play a central role in SbIII and MIL induced cell death in this parasite. Enriched mitochondrial samples from Leishmania promastigotes selected step by step for in vitro resistance to SbIII and MIL were subjected to differential proteomic analysis. A shared decrease in both mutants in the levels of pyruvate dehydrogenase, dihydrolipoamide dehydrogenase, and isocitrate dehydrogenase was observed, as well as a differential abundance in two calcium-binding proteins and the unique dynamin-1-like protein of the parasite. Both mutants presented a shared increase in the succinyl-CoA:3-ketoacid-coenzyme A transferase and the abundance of numerous hypothetical proteins was also altered in both mutants. In general, the proteomic changes observed in the MIL mutant were less pronounced than in the SbIII mutant, probably due to the early appearance of a mutation in the miltefosine transporter abrogating the need for a strong mitochondrial adaptation. This study is the first analysis of the Leishmania mitochondrial proteome and offers powerful insights into the adaptations to this organelle during SbIII and MIL drug resistance.

  5. 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.

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

    Directory of Open Access Journals (Sweden)

    2009-04-01

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

  7. 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.

  8. Two cases of visceral leishmaniasis in Colombia resistant to meglumine antimonial treatment.

    Science.gov (United States)

    Vélez, Iván Darío; Colmenares, Lina María; Muñoz, Carlos Aguirre

    2009-01-01

    Visceral leishmaniasis (VL) affects over 500,000 people worldwide each year. The disease occurs in the Mediterranean basin, Central and South America and is caused by Leishmania infantum (syn L. chagasi). VL is an endemic disease in Colombia, particularly along the Caribbean coast and the Magdalena River Valley and 90% of VL cases occur in children under the age of five. The first line of treatment is chemotherapy with pentavalent antimonial compounds, including sodium stibogluconate (Pentostam) and meglumine antimoniate (Glucantime). These compounds are the ones most used in Colombia, at a dose of 20 mg/kg/day for 28 days. Nevertheless resistance of L. infantum to pentavalent antimonials is becoming an important problem. No cases of VL resistant to pentavalent antimonial compounds have previously been reported from Colombia. This report describes the two cases of VL resistance to antimonial compounds in a girl and a boy who did not respond to previous treatment with Pentacarinat and Glucantime regimens but were treated successfully with liposomal amphotericin B. Based on our findings, we recommend liposomal amphotericin B as the first line of treatment for VL due to its low toxicity, shorter administration period and the low price obtained by WHO.

  9. 40 CFR 415.510 - Applicability; description of the potassium iodide production subcategory.

    Science.gov (United States)

    2010-07-01

    ... potassium iodide production subcategory. 415.510 Section 415.510 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Potassium Iodide Production Subcategory § 415.510 Applicability; description of the potassium iodide production subcategory. The provisions of this subpart are applicable to...

  10. The electrosorption of tetraalkylammonium ions on silver iodide

    NARCIS (Netherlands)

    Keizer, de A.

    1981-01-01

    The object of the present investigations was to study the ef fect of the adsorption of charged organic ions on electrically charged, solid-liquid interfaces. To that end, symmetrical quater nary ammonium ions were adsorbed on a silver iodide-electrolyte interface at various surface charges. The elec

  11. Confinement Effects in Low-Dimensional Lead Iodide Perovskite Hybrids

    NARCIS (Netherlands)

    Kamminga, Machteld E.; Fang, Honghua; Filip, Marina R.; Giustino, Feliciano; Baas, Jacobus; Blake, Graeme R.; Loi, Maria Antonietta; Palstra, Thomas T. M.

    2016-01-01

    We use a layered solution crystal growth technique to synthesize high-quality single crystals of phenylalkylammonium lead iodide organic/inorganic hybrid compounds. Single-crystal X-ray diffraction reveals low-dimensional structures consisting of inorganic sheets separated by bilayers of the organic

  12. Radiation-hard polycrystalline mercuric iodide semiconductor particle counters

    Energy Technology Data Exchange (ETDEWEB)

    Schieber, M. [Hebrew Univ., Jerusalem (Israel)]|[Sandia National Laboratories, Livermore Ca 94556 (United States); Zuck, A.; Melekhov, L.; Nissenbaum, J. [Hebrew Univ., Jerusalem (Israel); Turchetta, R.; Dulinski, W.; Husson, D.; Riester, J.L. [LEPSI (ULP/IN2P3), Strasbourg (France)

    1998-06-01

    Mercuric iodide polycrystalline radiation detectors, which can act as nuclear particle counters and for large area imaging devices, have been fabricated using three different methods. Response to X- and gamma rays, beta particles and to 100GeV muons, as well as radiation hardness results are briefly described. (orig.) 8 refs.

  13. 21 CFR 520.763b - Dithiazanine iodide powder.

    Science.gov (United States)

    2010-04-01

    ....763b Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... is administered to dogs by mixing the proper dosage in the dog's food, using the following dosage... contraindicated in animals sensitive to dithiazanine iodide and should be used cautiously, if at all, in dogs...

  14. 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.

  15. Preparation of highly dispersed antimony-doped tin oxide nanopowders by azeotropic drying with isoamyl acetate

    Institute of Scientific and Technical Information of China (English)

    YANG Fen; ZHANG Xue-jun; WU Xu; TIAN Fang; GAN Fu-xing

    2007-01-01

    Antimony-doped tin hydroxide colloid precipitates were prepared by hydrolysis of SnCl4-5H2O and SbCl3 ethanol solutions. Isoamyl acetate was selected as azeotropic drying solvent and was compared with the most commonly used n-butanol solvent on treating precipitate for low hard agglomeration precursor powders. The FT-IR, BET, XRD, and TEM results of the precursor powders and calcinated antimony-doped tin oxide powders were recorded. The results demonstrate that isoamyl acetate is an excellent azeotropic drying solvent that can effectively prevent the agglomeration of particles and greatly improve the fluffiness of the obtained dried powders. After these precursor powders are calcined, antimony-doped tin oxide nanopowders with tetragonal rutile structure and high dispersivity can be obtained.

  16. 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.

  17. Concentration transient analysis of antimony surface segregation during Si(100) molecular beam epitaxy

    Science.gov (United States)

    Markert, L. C.; Greene, J. E.; Ni, W.-X.; Hansson, G. V.; Sundgren, J.-E.

    1991-01-01

    Antimony surface segregation during Si(100) molecular beam epitaxy (MBE) was investigated at temperatures T(sub s) = 515 - 800 C using concentration transient analysis (CTA). The dopant surface coverage Theta, bulk fraction gamma, and incorporation probability sigma during MBE were determined from secondary-ion mass spectrometry depth profiles of modulation-doped films. Programmed T(sub s) changes during growth were used to trap the surface-segregated dopant overlayer, producing concentration spikes whose integrated area corresponds to Theta. Thermal antimony doping by coevaporation was found to result in segregation strongly dependent on T(sub s) with Theta(sub Sb) values up to 0.9 monolayers (ML): in films doped with Sb(+) ions accelerated by 100 V, Theta(sub Sb) was less than or equal to 4 x 10(exp -3) ML. Surface segregation of coevaporated antimony was kinematically limited for the film growth conditions in these experiments.

  18. 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

    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.

  19. FY-2015 Methyl Iodide Deep-Bed Adsorption Test Report

    Energy Technology Data Exchange (ETDEWEB)

    Soelberg, Nicholas Ray [Idaho National Lab. (INL), Idaho Falls, ID (United States); Watson, Tony Leroy [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-09-30

    Nuclear fission produces fission and activation products, including iodine-129, which could evolve into used fuel reprocessing facility off-gas systems, and could require off-gas control to limit air emissions to levels within acceptable emission limits. Deep-bed methyl iodide adsorption testing has continued in Fiscal Year 2015 according to a multi-laboratory methyl iodide adsorption test plan. Updates to the deep-bed test system have also been performed to enable the inclusion of evaporated HNO3 and increased NO2 concentrations in future tests. This report summarizes the result of those activities. Test results showed that iodine adsorption from gaseous methyl iodide using reduced silver zeolite (AgZ) resulted in initial iodine decontamination factors (DFs, ratios of uncontrolled and controlled total iodine levels) under 1,000 for the conditions of the long-duration test performed this year (45 ppm CH3I, 1,000 ppm each NO and NO2, very low H2O levels [3 ppm] in balance air). The mass transfer zone depth exceeded the cumulative 5-inch depth of 4 bed segments, which is deeper than the 2-4 inch depth estimated for the mass transfer zone for adsorbing I2 using AgZ in prior deep-bed tests. The maximum iodine adsorption capacity for the AgZ under the conditions of this test was 6.2% (6.2 g adsorbed I per 100 g sorbent). The maximum Ag utilization was 51%. Additional deep-bed testing and analyses are recommended to (a) expand the data base for methyl iodide adsorption and (b) provide more data for evaluating organic iodide reactions and reaction byproducts for different potential adsorption conditions.

  20. 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.

  1. Antimony trifluoride-modified carbon paste electrode for electrochemical stripping analysis of selected heavy metals

    OpenAIRE

    Stočes, Matěj; Hočevar, Samo B.; Švancara, Ivan

    2011-01-01

    In this article, a new typ of non-mercury metal-based electrode, antimony trifluoridebulk- modified carbon paste electrode (SbF3-CPE) is for the first time reported and examined for electrochemical stripping analysis of selected heavy metal ions at their trace concentration level. In the role of bulk modifier and a source of antimony film generated in state nascenti, SbF3 in a content of 3% (w/w) in the carbon paste mixture was the ultimate choice. All important experimental parameters hav...

  2. Defective organification of iodide causing congenital goitrous hypothyroidism.

    Science.gov (United States)

    Ishikawa, N; Eguchi, K; Ohmori, T; Momotani, N; Nagayama, Y; Hosoya, T; Oguchi, H; Mimura, T; Kimura, S; Nagataki, S; Ito, K

    1996-01-01

    A 26-yr-old Japanese woman with congenital goitrous hypo-thyroidism and sensorineural deafness underwent a thyroidectomy. Examination of the thyroid gland revealed characteristic features of multinodular goiter. The T3 and T4 content in thyroglobulin (Tg) were 0.03 and 0.02 mol/mol Tg, respectively. Iodide incorporation into Tg, using slices of the thyroid tissue, revealed that iodide organification of thyroid tissue from our patient was markedly lower than that of normal controls. Then, guaiacol and iodide oxidation activities of thyroid peroxidase (TPO) in our patient's thyroid tissue were lower than those of normal controls (guaiacol assay: 1.92 vs. 30.0 +/- 5.7 mGU/mg protein; iodide assay: 1.1 vs. 6.6 +/- 2.8 mIU/mg protein). Lineweaver-Burk plot analysis of the oxidation rates of guaiacol and iodide indicated that this patient's TPO had a defect in the binding of guaiacol and iodide, but the coupling activity of the patient's TPO was not decreased compared with those of two normal thyroids. In this case and in control subjects, Nothern gel analysis of TPO messenger RNA from unstimulated and TSH-stimulated thyroid cells revealed a 3.2 kilobase species in the former and four distinct messenger RNA species of 4.0, 3.2, 2.1, and 1.7 kilobases in the latter. Western blot analysis of TPOs obtained from this patient and from control subjects identified the same 107 kDa protein, using antimicrosomal antibody-positive serum. We analyzed the coding sequence in the patient's TPO gene by using polymerase chain reaction technique. A single point mutation of G-->C at 1265 base pair was detected only in the TPO gene, but this point mutation does not alter the amino acid residue. It is possible that posttranslational modification such as abnormal glycosylation may occur in the TPO molecules. Furthermore, it is possible that there are differences in the tertiary structures of the TPO molecules between our patient and normal subjects. The above abnormalities of TPO molecules

  3. [Evaluation of potassium iodide in Polish dietary salt].

    Science.gov (United States)

    Andrzejewska, E; Rokicka, B; Gajda, J; Jarecka, J; Oraczewska, A; Karłowski, K

    1996-01-01

    The consequences of iodine deficiency occurring still in Poland include serious health disorders in the population, such as psycho- somatic retardation, hypothyroidism, endemic goitre, even cretinism. Administration of iodized edible salt with daily diet is an effective method for prevention of iodine deficiency. The condition of success is the proper level of potassium iodide in this salt and adequate distribution of iodized salt in various regions of the country. Successful iodine prophylaxis should be based on iodination of edible salt in amounts of 30 +/- 10 mg of KJ/kg. The permission given in the period from February to May 1994 by the General Sanitary Inspector for the production and marketing of edible salt iodized in proportions of 30 +/- 10 mg KJ/kg opened the possibility of starting its production in salt mines. The purpose of the presently reported work was to assess, in cooperation with the Province Sanitary Epidemiological Stations, the adequacy of iodination of the Polish edible salt produced in the years 1994-1995. The study was carried out according to the Polish Standard "Salt (Sodium Chloride) /PN-80/C-84081.35. Potassium iodide determination by photo colorimetric method." In 1995 the number of edible salt samples analyzed was 2484, and this number included 2129 samples of iodized salt. Potassium iodide content agreeing with the above permission was found in 122 samples, that is in 57.4% of iodized salt samples. In 603 samples (28.3%) of iodized salt this content was below that given in the permissions. In 1994 this study was carried out taking 2172 samples of edible salt, including 1586 samples of iodized salt. The content of potassium iodide agreeing with the permissions (30 +/- 10 mg/kg) was found in 342 samples (28, 1%), but 272 (22.4%) samples of iodized salt produced by salt mines contained lower amounts of potassium iodide than the amount indicated in the permissions, but still within the limits set down in the Polish Standard (20 +/- 5 mg

  4. 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.

  5. Purification and deposition of silicon by an iodide disproportionation reaction

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Tihu (Littleton, CO); Ciszek, Theodore F. (Evergreen, CO)

    2002-01-01

    Method and apparatus for producing purified bulk silicon from highly impure metallurgical-grade silicon source material at atmospheric pressure. Method involves: (1) initially reacting iodine and metallurgical-grade silicon to create silicon tetraiodide and impurity iodide byproducts in a cold-wall reactor chamber; (2) isolating silicon tetraiodide from the impurity iodide byproducts and purifying it by distillation in a distillation chamber; and (3) transferring the purified silicon tetraiodide back to the cold-wall reactor chamber, reacting it with additional iodine and metallurgical-grade silicon to produce silicon diiodide and depositing the silicon diiodide onto a substrate within the cold-wall reactor chamber. The two chambers are at atmospheric pressure and the system is open to allow the introduction of additional source material and to remove and replace finished substrates.

  6. Synthesis and Structure of Bis(4-nitrobenzaldehyde thiosemicarbazone) Cadmium Iodide

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The title complex, bis(4-nitrobenzaldehyde thiosemicarbazone) cadmium iodide (C16H16CdI2N8O4S2) crystallizes in the triclinic system, space group P1 with a=9.632(2), b=11.227(2), c=14.031(3), α= 67.50(3), β= 86.99(3), γ= 66.64(3)°, V=1278.13, Z = 2, Dc = 2.117gcm-3, F(000) = 772, μ =3.472mm-1 MoKα radiation (λ=0.71073), R = 0.0443, wR= 0.1425 for 4529 observed reflections [I>2σ(I)] of 4731 independent reflections. The result shows that the structure contains CdL2I2 (where L = 4-nitrobenzaldehyde thiosemicarbazone) distorted tetrahedral units in which the two ligands are S-bonded as monodentate to cadmium ion; the two iodide ions are also coordinated to Cd(II).

  7. Mechanisms of antimony adsorption onto soybean stover-derived biochar in aqueous solutions

    Science.gov (United States)

    Limited mechanistic knowledge is available to understand how biochar interacts with trace elements that exist predominantly as oxoanions, such as antimony (Sb). Soybean stover biochars were produced at 300 degrees C (SBC300) and 700 degrees C (SBC700), and were characterized by BET, Boehm titration,...

  8. 78 FR 59679 - Antimony Trioxide TSCA Chemical Risk Assessment; Notice of Public Meetings and Opportunity To...

    Science.gov (United States)

    2013-09-27

    ... Scientific Consulting Group (SCG), Inc., has identified a panel of scientific experts to conduct a peer... Chemical Risk Assessment for Antimony Trioxide.'' EPA will hold three peer review meetings by web connect... speakers providing oral comments during any or all of the peer review meetings as discussed in this...

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

    Directory of Open Access Journals (Sweden)

    NDONGO GUEYE

    2013-12-01

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

  10. Dredging Operations Technical Support Program. Transformation, Fixation, and Mobilization of Arsenic and Antimony in Contaminated Sediments.

    Science.gov (United States)

    1984-01-01

    ANTIMONY IN CONTAMINATED SEDIMENTS Final report 6. PERFORMING ORG. REPORT NUMBER 7. AUTHOR(.) 8. CONTRACT OR GRANT NUMBER(s) James M. Brannon 9...additional Sb when leached with saline water. Long-term (six months) releases of Sb were mucl higher from Sb amended sediments than from sediments

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

    Science.gov (United States)

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

    2017-04-01

    Major uses of thermoelectricity concern refrigeration purposes, using Peltier devices, mainly composed of antimony, bismuth and tellurium. Antimony was identified as a critical raw material by EU and resources of bismuth and tellurium are not inexhaustible, so it is necessary to imagine the recycling of thermoelectric devices. That for, a complete characterization is needed, which is the aim of this work. Peltier devices were manually dismantled in three parts: the thermoelectric legs, the alumina plates on which remain the electrical contacts and the silicone paste used to connect the plates. The characterization was performed using five Peltier devices. It includes mass balances of the components, X-ray diffraction analysis of the thermoelectric legs and elemental analysis of each part of the device. It appears that alumina represents 45% of a Peltier device in weight. The electrical contacts are mainly composed of copper and tin, and the thermoelectric legs of bismuth, tellurium and antimony. Thermoelectric legs appear to be Se-doped Bi2Te3 and (Bi0,5Sb1,5)Te3 for n type and p type semiconductors, respectively. This work shows that Peltier devices can be considered as a copper ore and that thermoelectric legs contain high amounts of bismuth, tellurium and antimony compared to their traditional resources.

  12. 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.

  13. 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,

  14. 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.

  15. 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.

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

    Directory of Open Access Journals (Sweden)

    Shafa Muhammad

    2016-09-01

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

  17. Caloric Effects in Methylammonium Lead Iodide from Molecular Dynamics Simulations

    OpenAIRE

    Liu, Shi; Cohen, Ronald E.

    2016-01-01

    Organic-inorganic hybrid perovskite architecture could serve as a robust platform for materials design to realize functionalities beyond photovoltaic applications. We explore caloric effects in organometal halide perovskites, taking methylammonium lead iodide (MAPbI$_3$) as an example, using all-atom molecular dynamics simulations with a first-principles based interatomic potential. The adiabatic thermal change is estimated directly by introducing different driving fields in the simulations. ...

  18. Structural insight into iodide uptake by AFm phases.

    Science.gov (United States)

    Aimoz, Laure; Wieland, Erich; Taviot-Guého, Christine; Dähn, Rainer; Vespa, Marika; Churakov, Sergey V

    2012-04-03

    The ability of cement phases carrying positively charged surfaces to retard the mobility of (129)I, present as iodide (I(-)) in groundwater, was investigated in the context of safe disposal of radioactive waste. (125)I sorption experiments on ettringite, hydrotalcite, chloride-, carbonate- and sulfate-containing AFm phases indicated that calcium-monosulfate (AFm-SO(4)) is the only phase that takes up trace levels of iodide. The structures of AFm phases prepared by coprecipitating iodide with other anions were investigated in order to understand this preferential uptake mechanism. X-ray diffraction (XRD) investigations showed a segregation of monoiodide (AFm-I(2)) and Friedel's salt (AFm-Cl(2)) for I-Cl mixtures, whereas interstratifications of AFm-I(2) and hemicarboaluminate (AFm-OH-(CO(3))(0.5)) were observed for the I-CO(3) systems. In contrast, XRD measurements indicated the formation of a solid solution between AFm-I(2) and AFm-SO(4) for the I-SO(4) mixtures. Extended X-ray absorption fine structure spectroscopy showed a modification of the coordination environment of iodine in I-CO(3) and in I-SO(4) samples compared to pure AFm-I(2). This is assumed to be due to the introduction of stacking faults in I-CO(3) samples on one hand and due to the presence of sulfate and associated space-filling water molecules as close neighbors in I-SO(4) samples on the other hand. The formation of a solid solution between AFm-I(2) and AFm-SO(4), with a short-range mixing of iodide and sulfate, implies that AFm-SO(4) bears the potential to retard (129)I.

  19. Development of the strontium iodide coded aperture (SICA) instrument

    Science.gov (United States)

    Mitchell, Lee J.; Phlips, Bernard F.; Grove, J. Eric; Cordes, Ryan

    2015-08-01

    The work reports on the development of a Strontium Iodide Coded Aperture (SICA) instrument for use in space-based astrophysics, solar physics, and high-energy atmospheric physics. The Naval Research Laboratory is developing a prototype coded aperture imager that will consist of an 8 x 8 array of SrI2:Eu detectors, each read out by a silicon photomultiplier. The array would be used to demonstrate SrI2:Eu detector performance for space-based missions. Europium-doped strontium iodide (SrI2:Eu) detectors have recently become available, and the material is a strong candidate to replace existing detector technology currently used for space-based gamma-ray astrophysics research. The detectors have a typical energy resolution of 3.2% at 662 keV, a significant improvement over the 6.5% energy resolution of thallium-doped sodium iodide. With a density of 4.59 g/cm and a Zeff of 49, SrI2:Eu has a high efficiency for MeV gamma-ray detection. Coupling this with recent improvements in silicon photomultiplier technology (i.e., no bulky photomultiplier tubes) creates high-density, large-area, low-power detector arrays with good energy resolution. Also, the energy resolution of SrI2:Eu makes it ideal for use as the back plane of a Compton telescope.

  20. Gold nanoelectrode ensembles for direct trace electroanalysis of iodide.

    Science.gov (United States)

    Pereira, Francisco C; Moretto, Ligia M; De Leo, Manuela; Zanoni, Maria V Boldrin; Ugo, Paolo

    2006-08-01

    A procedure for the standardization of ensembles of gold nanodisk electrodes (NEE) of 30 nm diameter is presented, which is based on the analytical comparison between experimental cyclic voltammograms (CV) obtained at the NEEs in diluted solutions of redox probes and CV patterns obtained by digital simulation. Possible origins of defects sometimes found in NEEs are discussed. Selected NEEs are then employed for the study of the electrochemical oxidation of iodide in acidic solutions. CV patterns display typical quasi-reversible behavior which involves associated chemical reactions between adsorbed and solution species. The main CV characteristics at the NEE compare with those observed at millimeter sized gold disk electrodes (Au-macro), apart a slight shift in E1/2 values and slightly higher peak to peak separation at the NEE. The detection limit (DL) at NEEs is 0.3 microM, which is more than one order of magnitude lower than DL at the Au-macro (4 microM). The mechanism of the electrochemical oxidation of iodide at NEEs is discussed. Finally, NEEs are applied to the direct determination of iodide at micromolar concentration levels in real samples, namely in some ophthalmic drugs and iodized table salt.

  1. Enhanced iodide sequestration by 3-biphenyl-5,6-dihydroimidazo 2,1-b thiazole in sodium/iodide sym-porter (NIS)-expressing cells

    Energy Technology Data Exchange (ETDEWEB)

    Lecat-Guillet, N.; Ambroise, Y. [CEA, DSV, Dept Bioorgan Chem andt IsotopLabelling, Inst Biol and Technol, iBiTecS, F-91191 Gif Sur Yvette (France)

    2008-07-01

    The ability of the sodium/iodide sym-porter (NIS) to take up iodide has long provided the basis for cyto-reductive gene therapy and cancer treatment with radio-iodide. One of the major limitations of this approach is that radio-iodide retention in NIS-expressing cells is not sufficient for their destruction. We identified and characterized a small organic molecule capable of increasing iodide retention in HEK293 cells permanently transfected with human NIS cDNA (hNIS-HEK293) and in the rat thyroid-derived cell line FRTL-5. In the presence of 3-biphenyl-4'-yl-5,6-dihydroimidazo[2,1-b)thiazole (ISA1), the transmembrane iodide concentration gradient was increased up to 4.5-fold. Our experiments indicate that the imidazo-thiazole derivative acts either by inhibiting anion efflux mechanisms, or by promoting the relocation of iodide into subcellular compartments. This new compound is not only an attractive chemical tool to investigate the mechanisms of iodide flux at the cellular level, but also opens promising perspectives in the treatment of cancer after NIS gene transfer. (authors)

  2. Removal and sequestration of iodide using silver-impregnated activated carbon.

    Science.gov (United States)

    Hoskins, Jay S; Karanfil, Tanju; Serkiz, Steven M

    2002-02-15

    Two silver-impregnated activated carbons (SIACs) (0.05 and 1.05 wt % silver) and their virgin (i.e., unimpregnated) granular activated carbon (GAC) precursors were investigated for their ability to remove and sequester iodide from aqueous solutions in a series of batch sorption and leaching experiments. Silver content, total iodide concentration, and pH were the factors controlling the removal mechanisms of iodide. Iodide uptake increased with decreasing pH for both SIACs and their virgin GACs. The 0.05% SIAC behaved similarly to its virgin GAC in all experimental conditions because of its low silver content. At pH values of 7 and 8 there was a marked increased in iodide removal for the 1.05% SIAC over that of its virgin GAC, while their performances were similar at a pH of 5. Scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) analyses prior to reaction with iodide showed the presence of metallic silver agglomerates on the 1.05% SIAC surface. After the reaction, elemental mapping with EDX showed the formation of silver iodide agglomerates. Oxidation of metallic silver was observed in the presence of oxygen, and the carbon surface appears to catalyze this reaction. When the molar ratio of silver to iodide was greater than 1 (i.e., M(Ag,SIAC) > M(I,TOTAL)), precipitation of silver iodide was the dominant removal mechanism. However, unreacted silver leached into solution with decreasing pH while iodide leaching did not occur. When M(Ag,SIAC) silver iodide precipitation occurred until all available silver had reacted, and additional iodide was removed from solution by pH-dependent adsorption to the GAC. Under this condition, silver leaching did not occur while iodide leaching increased with increasing pH.

  3. Electrochemistry of silver iodide the capacity of the double layer at the silver iodide-water interface

    NARCIS (Netherlands)

    Lyklema, J.; Overbeek, J.Th.G.

    1961-01-01

    A method is described for obtaining differential double layer capacities on silver iodide. Especially the influence of the nature and concentration of indifferent electrolytes was investigated, viz., the nitrates of Li·, K·, Rb·, NH4·, H·, Tl·, Mg··, Ba··, Co··, Cd··, Pb··, La···, Th····, the fluori

  4. Iron- Catalyzed 1,2-Addition of Perfluoroalkyl Iodides to Alkynes and Alkenes

    OpenAIRE

    Xu, Tao; Cheung, Chi Wai; Hu, Xile

    2014-01-01

    Iron catalysis has been developed for the intermolecular 1,2-addition of perfluoroalkyl iodides to alkynes and alkenes. The catalysis has a wide substrate scope and high functional-group tolerance. A variety of perfluoroalkyl iodides including CF3I can be employed. The resulting perfluoroalkylated alkyl and alkenyl iodides can be further functionalized by cross-coupling reactions. This methodology provides a straightforward and streamlined access to perfluoroalkylated organic molecules.

  5. Expression of sodium-iodide symporter in thyroid gland tumors: immunohistochemical study

    Directory of Open Access Journals (Sweden)

    Bondarenko O.O.

    2009-01-01

    Full Text Available One of the key moments of radioiodine therapy, and also radioisotope diagnostics of cancers of a thyroid gland is ability of their cells to accumulate iodide. This ability is provided with activity of the specific transporter – sodium-iodide symporter. Our research has shown disorders of sodium-iodide symporter immunoexpression in all tumors of thyroid gland: from overexpression and absence of plasma membrane expression in differentiated carcinomas, up to weak or actually absent in low differentiated cancers and Hurtle-cells tumors. Thus, there is a prospect of application of the sodium-iodide symporter, as the prognostic marker of thyroid cancers.

  6. Optical properties and surface morphology studies of palladium contacts on mercuric iodide single crystals

    Energy Technology Data Exchange (ETDEWEB)

    George, M.A.; Azoulay, M.; Burger, A.; Biao, Y.; Silberman, E. [Fisk Univ., Nashville, TN (United States). Dept. of Physics; Nason, D. [EG and G Energy Measurements, Inc., Goleta, CA (United States). Santa Barbara Operations

    1993-05-01

    Palladium is chemically suitable for electric contacts on mercuric iodide detectors for photon and nuclear radiation detection, so the understanding of palladium contacts is important for fundamental and practical scientific purposes. A study has been conducted on the surface morphology of evaporated contacts using Atomic Force Microscopy (AFM) and optical transmission and reflection. Evaporated palladium coatings are typically nonuniform and may deposit selectively on mercuric iodide surface defects. Reflection measurements show that coating thickness and surface treatment affect intensity, position and shape of a reflected peak characteristic of the mercuric iodide structure. Results indicate that the band gap energy in the surface of the mercuric iodide is lowered by palladium contacts.

  7. Optical properties and surface morphology studies of palladium contacts on mercuric iodide single crystals

    Science.gov (United States)

    George, M. A.; Azoulay, M.; Burger, A.; Biao, Y.; Silberman, E.; Nason, D.

    1993-04-01

    Palladium is chemically suitable for electric contacts on mercuric iodide detectors for photon and nuclear radiation detection, so the understanding of palladium contacts is important for fundamental and practical scientific purposes. A study has been conducted on the surface morphology of evaporated contacts using atomic force microscopy (AFM) and optical transmission and reflection. Evaporated palladium coatings are typically nonuniform and may deposit selectively on mercuric iodide surface defects. Reflection measurements show that coating thickness and surface treatment affect intensity, position, and shape of a reflected peak characteristic of the mercuric iodide structure. Results indicate that the band gap energy in the surface of the mercuric iodide is lowered by palladium contacts.

  8. Overexpression of ubiquitin and amino acid permease genes in association with antimony resistance in Leishmania tropica field isolates.

    Science.gov (United States)

    Kazemi-Rad, Elham; Mohebali, Mehdi; Khadem-Erfan, Mohammad Bagher; Hajjaran, Homa; Hadighi, Ramtin; Khamesipour, Ali; Rezaie, Sassan; Saffari, Mojtaba; Raoofian, Reza; Heidari, Mansour

    2013-08-01

    The mainstay therapy against leishmaniasis is still pentavalent antimonial drugs; however, the rate of antimony resistance is increasing in endemic regions such as Iran. Understanding the molecular basis of resistance to antimonials could be helpful to improve treatment strategies. This study aimed to recognize genes involved in antimony resistance of Leishmania tropica field isolates. Sensitive and resistant L. tropica parasites were isolated from anthroponotic cutaneous leishmaniasis patients and drug susceptibility of parasites to meglumine antimoniate (Glucantime®) was confirmed using in vitro assay. Then, complementary DNA-amplified fragment length polymorphism (cDNA-AFLP) and real-time reverse transcriptase-PCR (RT-PCR) approaches were utilized on mRNAs from resistant and sensitive L. tropica isolates. We identified 2 known genes, ubiquitin implicated in protein degradation and amino acid permease (AAP3) involved in arginine uptake. Also, we identified 1 gene encoding hypothetical protein. Real-time RT-PCR revealed a significant upregulation of ubiquitin (2.54-fold), and AAP3 (2.86-fold) (P<0.05) in a resistant isolate compared to a sensitive one. Our results suggest that overexpression of ubiquitin and AAP3 could potentially implicated in natural antimony resistance.

  9. 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.

  10. Strontium iodide gamma ray spectrometers for planetary science (Conference Presentation)

    Science.gov (United States)

    Prettyman, Thomas H.; Rowe, Emmanuel; Butler, Jarrhett; Groza, Michael; Burger, Arnold; Yamashita, Naoyuki; Lambert, James L.; Stassun, Keivan G.; Beck, Patrick R.; Cherepy, Nerine J.; Payne, Stephen A.; Castillo-Rogez, Julie C.; Feldman, Sabrina M.; Raymond, Carol A.

    2016-09-01

    Gamma rays produced passively by cosmic ray interactions and by the decay of radioelements convey information about the elemental makeup of planetary surfaces and atmospheres. Orbital missions mapped the composition of the Moon, Mars, Mercury, Vesta, and now Ceres. Active neutron interrogation will enable and/or enhance in situ measurements (rovers, landers, and sondes). Elemental measurements support planetary science objectives as well as resource utilization and planetary defense initiatives. Strontium iodide, an ultra-bright scintillator with low nonproportionality, offers significantly better energy resolution than most previously flown scintillators, enabling improved accuracy for identification and quantification of key elements. Lanthanum bromide achieves similar resolution; however, radiolanthanum emissions obscure planetary gamma rays from radioelements K, Th, and U. The response of silicon-based optical sensors optimally overlaps the emission spectrum of strontium iodide, enabling the development of compact, low-power sensors required for space applications, including burgeoning microsatellite programs. While crystals of the size needed for planetary measurements (>100 cm3) are on the way, pulse-shape corrections to account for variations in absorption/re-emission of light are needed to achieve maximum resolution. Additional challenges for implementation of large-volume detectors include optimization of light collection using silicon-based sensors and assessment of radiation damage effects and energetic-particle induced backgrounds. Using laboratory experiments, archived planetary data, and modeling, we evaluate the performance of strontium iodide for future missions to small bodies (asteroids and comets) and surfaces of the Moon and Venus. We report progress on instrument design and preliminary assessment of radiation damage effects in comparison to technology with flight heritage.

  11. Electronic properties and Compton profiles of silver iodide

    Indian Academy of Sciences (India)

    Alpa Dashora; Ambica Marwal; K R Soni; B L Ahuja

    2010-06-01

    We have carried out an extensive study of electronic properties of silver iodide in - and -phases. The theoretical Compton profiles, energy bands, density of states and anisotropies in momentum densities are computed using density functional theories. We have also employed full-potential linearized augmented plane-wave method to derive the energy bands and the density of states. To compare our theoretical data, isotropic Compton profile measurement on -AgI using 137Cs Compton spectrometer at an intermediate resolution of 0.38 a.u. has been undertaken. The theoretical anisotropies are also interpreted on the basis of energy bands.

  12. Temperature dependent energy levels of methylammonium lead iodide perovskite

    Energy Technology Data Exchange (ETDEWEB)

    Foley, Benjamin J.; Marlowe, Daniel L.; Choi, Joshua J., E-mail: jjc6z@virginia.edu, E-mail: mgupta@virginia.edu, E-mail: scudiero@wsu.edu [Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States); Sun, Keye; Gupta, Mool C., E-mail: jjc6z@virginia.edu, E-mail: mgupta@virginia.edu, E-mail: scudiero@wsu.edu [Department of Electrical and Computer Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States); Saidi, Wissam A. [Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15261 (United States); Scudiero, Louis, E-mail: jjc6z@virginia.edu, E-mail: mgupta@virginia.edu, E-mail: scudiero@wsu.edu [Chemistry Department and Materials Science and Engineering Program, Washington State University, Pullman, Washington 99164 (United States)

    2015-06-15

    Temperature dependent energy levels of methylammonium lead iodide are investigated using a combination of ultraviolet photoemission spectroscopy and optical spectroscopy. Our results show that the valence band maximum and conduction band minimum shift down in energy by 110 meV and 77 meV as temperature increases from 28 °C to 85 °C. Density functional theory calculations using slab structures show that the decreased orbital splitting due to thermal expansion is a major contribution to the experimentally observed shift in energy levels. Our results have implications for solar cell performance under operating conditions with continued sunlight exposure and increased temperature.

  13. Polarized spectral complexes of optical functions of monovalent mercury iodide

    Science.gov (United States)

    Sobolev, V. V.; Sobolev, V. Val.; Anisimov, D. V.

    2015-12-01

    Spectral complexes of optical functions of monovalent mercury iodide Hg2I2 were determined for E ⊥ c and E || c polarizations in the range from 2 to 5.5 eV at 4.2 K. The permittivity and characteristic electron energy loss spectra were expanded in simple components with the determination of their main parameters, including the energy of the maximum and the oscillator strength. The calculations were performed based on known reflectance spectra. Computer programs based on Kramers-Kronig relations and the improved parameter-free method of Argand diagrams were used.

  14. Electrolytic coloration of hydroxyl-doped potassium iodide polycrystals

    Science.gov (United States)

    Wang, Na; Gu, Hongen; Han, Li; Guo, Meili; Qin, Fang

    2007-03-01

    Hydroxyl-doped potassium iodide polycrystals were successfully colored electrolytically by using a pointed cathode and a flat anode at various temperatures and electric field strengths, which mainly benefits appropriate coloration temperatures and electric field strengths. Characteristic OH-, O2--Va+ , U, V2, V3, Cu+, Cu-related, I2- , I2, K, F, R1 and R2 spectral bands were observed in Kubelka-Munk functions of the colored polycrystals, and the OH- and O2--Va+ spectral bands at room temperature were determined from Mollwo-Ivey plots. Color center formation in the electrolytic coloration was explained.

  15. 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.

  16. 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.

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

    Science.gov (United States)

    Shaji, S.; Garcia, L. V.; Loredo, S. L.; Krishnan, B.; Aguilar Martinez, J. A.; Das Roy, T. K.; Avellaneda, D. A.

    2017-01-01

    Antimony sulfide (Sb2S3) thin films were prepared by laser assisted chemical bath deposition (LACBD) technique. These thin films were deposited on glass substrates from a chemical bath containing antimony chloride, acetone and sodium thiosulfate under various conditions of normal chemical bath deposition (CBD) as well as in-situ irradiation of the chemical bath using a continuous laser of 532 nm wavelength. Structure, composition, morphology, optical and electrical properties of the Sb2S3 thin films produced by normal CBD and LACBD were analyzed by X-Ray diffraction (XRD), Raman Spectroscopy, Atomic force microscopy (AFM), X-Ray photoelectron spectroscopy (XPS), UV-vis spectroscopy and Photoconductivity. The results showed that LACBD is an effective synthesis technique to obtain Sb2S3 thin films for optoelectronic applications.

  18. Sandwich heterostructures of antimony trioxide and bismuth trioxide films: Structural, morphological and optical analysis

    Science.gov (United States)

    Condurache-Bota, Simona; Praisler, Mirela; Gavrila, Raluca; Tigau, Nicolae

    2017-01-01

    Thin film heterostructures can be advantageous since they either exhibit novel or a combination of the properties of their components. Here we propose sandwich-type of heterostructures made of antimony trioxide and bismuth trioxide thin films, which were deposited on glass substrates by thermal vacuum deposition at three substrate temperatures, 50° Celsius apart. Their morphology and optical properties are studied as compared to the corresponding monolayers. It was found that even small substrate temperature changes strongly influence their morphology, increasing their roughness, while the optical transmittance shows a slight decrease as compared with the individual layers. The corresponding absorption coefficient exhibits intermediate values as compared to the component oxides, while the energy bandgaps for the indirect allowed transitions move towards the Infrared when overlapping the antimony and bismuth trioxides.

  19. [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.

  20. Spectroscopic studies of lead antimony borate glasses doped with erbium ions

    Science.gov (United States)

    Reddy, M. Chandra Shekhar; Goud, K. Krishna Murthy; Dharmaiah, P.; Rao, B. Appa

    2013-06-01

    Antimony borate glasses of the composition 30PbO-25Sb2O3-(45-x)B2O3-xEr2O3 with x = 0 to 1.0 in steps of 0.2 were prepared by the melt-quenching method. Various physical parameters. radiative parameters, transition probability A, branching ratio β and the radiative life time τ for different emission levels of Er3+ ions, have been evaluated.

  1. Chemically deposited thin films of sulfides and selenides of antimony and bismuth as solar energy materials

    Science.gov (United States)

    Nair, M. T. S.; Nair, Padmanabhan K.; Garcia, Victor M.; Pena, Y.; Arenas, O. L.; Garcia, J. C.; Gomez-Daza, O.

    1997-10-01

    Chemical bath deposition techniques for bismuth sulfide, bismuth selenide, antimony sulfide, and antimony selenide thin films of about 0.20 - 0.25 micrometer thickness are reported. All these materials may be considered as solar absorber films: strong optical absorption edges, with absorption coefficient, (alpha) , greater than 104 cm-1, are located at 1.31 eV for Bi2Se3, 1.33 eV for Bi2S3, 1.8 eV for Sb2S3, and 1.35 eV for Sb2Se3. As deposited, all the films are nearly amorphous. However, well defined crystalline peaks matching bismuthinite (JCPDS 17- 0320), paraguanajuatite (JCPDS 33-0214), and stibnite (JCPDS 6-0474) and antimony selenide (JCPDS 15-0861) for Bi2S3, Bi2Se3, Sb2S3 and Sb2Se3 respectively, are observed when the films are annealed in nitrogen at 300 degrees Celsius. This is accompanied by a substantial modification of the electrical conductivity in the films: from 10-7 (Omega) -1 cm-1 (in as prepared films) to 10 (Omega) -1 cm-1 in the case of bismuth sulfide and selenide films, and enhancement of photosensitivity in the case of antimony sulfide films. The chemical deposition of a CuS/CuxSe film on these Vx- VIy films and subsequent annealing at 300 degrees Celsius for 1 h at 1 torr of nitrogen leads to the formation of p-type films (conductivity of 1 - 100 (Omega) -1 cm-1) of multinary composition. Among these, the formation of Cu3BiS3 (JCPDS 9-0488) and Cu3SbS4 (JCPDS 35- 0581), CuSbS2 (JCPDS 35-0413) have been clearly detected. Solar energy applications of these films are suggested.

  2. The heat capacity of solid antimony telluride Sb2Te3

    Science.gov (United States)

    Pashinkin, A. S.; Malkova, A. S.; Mikhailova, M. S.

    2008-05-01

    The literature data on the heat capacity of solid antimony telluride over the range 53 895 K were analyzed. The heat capacity of Sb2Te3 was measured over the range 350 700 K on a DSM-2M calorimeter. The equation for the temperature dependence was suggested. The thermodynamic functions of Sb2Te3 were calculated over the range 298.15 700 K.

  3. Thermo EMF and Hall effect behaviour of thin films of antimony-tellurium alloy

    Energy Technology Data Exchange (ETDEWEB)

    Dhiren Singh, N. (Dept. of Physics, Manipur Univ., Imphal (India)); Sarma, H.N.K. (Dept. of Physics, Manipur Univ., Imphal (India))

    1994-04-16

    This note presents the results of measurements of thermo emf and Hall effect of Sb[sub 40]Te[sub 60] alloy thin films. The alloy was prepared by taking a stoichiometric mixture (2:3) of high purity elements antimony and tellurium each of purity 99.999 (Koch-Light Laboratories Ltd., England) in a vacuum sealed quartz tube and heating in a furnace to a temperature of about 1070 K for 12 h. (orig.)

  4. 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.

  5. Persistent Energetic Electrons in Methylammonium Lead Iodide Perovskite Thin Films.

    Science.gov (United States)

    Niesner, Daniel; Zhu, Haiming; Miyata, Kiyoshi; Joshi, Prakriti P; Evans, Tyler J S; Kudisch, Bryan J; Trinh, M Tuan; Marks, Manuel; Zhu, X-Y

    2016-12-07

    In conventional semiconductor solar cells, carriers are extracted at the band edges and the excess electronic energy (E*) is lost as heat. If E* is harvested, power conversion efficiency can be as high as twice the Shockley-Queisser limit. To date, materials suitable for hot carrier solar cells have not been found due to efficient electron/optical-phonon scattering in most semiconductors, but our recent experiments revealed long-lived hot carriers in single-crystal hybrid lead bromide perovskites. Here we turn to polycrystalline methylammonium lead iodide perovskite, which has emerged as the material for highly efficient solar cells. We observe energetic electrons with excess energy ⟨E*⟩ ≈ 0.25 eV above the conduction band minimum and with lifetime as long as ∼100 ps, which is 2-3 orders of magnitude longer than those in conventional semiconductors. The energetic carriers also give rise to hot fluorescence emission with pseudo-electronic temperatures as high as 1900 K. These findings point to a suppression of hot carrier scattering with optical phonons in methylammonium lead iodide perovskite. We address mechanistic origins of this suppression and, in particular, the correlation of this suppression with dynamic disorder. We discuss potential harvesting of energetic carriers for solar energy conversion.

  6. Ionic transport in hybrid lead iodide perovskite solar cells

    Science.gov (United States)

    Eames, Christopher; Frost, Jarvist M.; Barnes, Piers R. F.; O'Regan, Brian C.; Walsh, Aron; Islam, M. Saiful

    2015-01-01

    Solar cells based on organic–inorganic halide perovskites have recently shown rapidly rising power conversion efficiencies, but exhibit unusual behaviour such as current–voltage hysteresis and a low-frequency giant dielectric response. Ionic transport has been suggested to be an important factor contributing to these effects; however, the chemical origin of this transport and the mobile species are unclear. Here, the activation energies for ionic migration in methylammonium lead iodide (CH3NH3PbI3) are derived from first principles, and are compared with kinetic data extracted from the current–voltage response of a perovskite-based solar cell. We identify the microscopic transport mechanisms, and find facile vacancy-assisted migration of iodide ions with an activation energy of 0.6 eV, in good agreement with the kinetic measurements. The results of this combined computational and experimental study suggest that hybrid halide perovskites are mixed ionic–electronic conductors, a finding that has major implications for solar cell device architectures. PMID:26105623

  7. Numerical modelling of methyl iodide in the eastern tropical Atlantic

    Directory of Open Access Journals (Sweden)

    I. Stemmler

    2013-06-01

    Full Text Available Methyl iodide (CH3I is a volatile organic halogen compound that contributes significantly to the transport of iodine from the ocean to the atmosphere, where it plays an important role in tropospheric chemistry. CH3I is naturally produced and occurs in the global ocean. The processes involved in the formation of CH3I, however, are not fully understood. In fact, there is an ongoing debate whether production by phytoplankton or photochemical degradation of organic matter is the main source term. Here, both the biological and photochemical production mechanisms are considered in a biogeochemical module that is coupled to a one-dimensional water column model for the eastern tropical Atlantic. The model is able to reproduce observed subsurface maxima of CH3I concentrations. But, the dominating source process cannot be clearly identified as subsurface maxima can occur due to both direct biological and photochemical production. However, good agreement between the observed and simulated difference between surface and subsurface methyl iodide concentrations is achieved only when direct biological production is taken into account. Production rates for the biological CH3I source that were derived from published laboratory studies are shown to be inappropriate for explaining CH3I concentrations in the eastern tropical Atlantic.

  8. Nuclear detonation, thyroid cancer and potassium iodide prophylaxis

    Directory of Open Access Journals (Sweden)

    Viroj Wiwanitkit

    2011-01-01

    Full Text Available The recent nuclear disaster at Japan has raised global concerns about effects of radioactive leakage in the environment, associated hazards, and how they can be prevented. In this article, we have tried to explain about the guidelines laid down by World Health Organization for a potassium iodide prophylaxis following a nuclear disaster, and its mechanism of action in preventing thyroid cancer. Data was collected mainly from the studies carried out during the Chernobyl disaster of Russia in 1986 and the hazardous effects especially on the thyroid gland were studied. It was seen that radioactive iodine leakage from the nuclear plants mainly affected the thyroid gland, and especially children were at a higher risk at developing the cancers. Potassium Iodide prophylaxis can be administered in order to prevent an increase in the incidence of thyroid cancers in the population of an area affected by a nuclear disaster. However, one has to be cautious while giving it, as using it without indication has its own risks.

  9. 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

  10. Altering the dewetting characteristics of ultrathin gold and silver films using a sacrificial antimony layer.

    Science.gov (United States)

    Farzinpour, P; Sundar, A; Gilroy, K D; Eskin, Z E; Hughes, R A; Neretina, S

    2012-12-14

    Solid state dewetting of ultrathin films is the most straightforward means of fabricating substrate-supported noble metal nanostructures. This assembly process is, however, quite inflexible, yielding either densely packed smaller structures or widely spaced larger structures. Here, we demonstrate the utility of introducing a sacrificial antimony layer between the substrate and noble metal overlayer. We observe an agglomeration process which is radically altered by the concurrent sublimation of antimony. In stark contrast with conventional dewetting, where the thickness of the deposited metal film determines the characteristic length scales of the assembly process, it is the thickness of the sacrificial antimony layer which dictates both the nanoparticle size and interparticle spacing. The result is a far more flexible self-assembly process where the nanoparticle size and areal density can be varied widely. Demonstrations show nanoparticle areal densities which are varied over four orders of magnitude assembled from the identical gold layer thickness, where the accompanying changes to nanostructure size see a systematic shift in the wavelength of the localized surface plasmon resonance. As a pliable self-assembly process, it offers the opportunity to tailor the properties of an ensemble of nanostructures to meet the needs of specific applications.

  11. Separation of Arsenic from the Antimony-Bearing Dust through Selective Oxidation Using CuO

    Science.gov (United States)

    Zhong, Da-Peng; Li, Lei; Tan, Cheng

    2017-01-01

    A pyrometallurgical process of selective oxidation roasting of the antimony-bearing dust using CuO is put forward, in which the antimony component is oxidized to Sb2O4 staying in the roasted residue, and arsenic is volatilized in the form of As2O3. The addition of CuO has an active effect on the arsenic volatilization, because structures of some complicated As-Sb phases in the dust are destroyed after the "Sb" component in them is oxidized to Sb2O4, and this part of arsenic might be transformed to As2O3, which continues to volatilize. However, the arsenic volatilization rate decreases with the CuO amount in a certain range, which is attributed to the greater formation of Cu3 (AsO4)2 and Cu3As. Under the conditions of roasting temperature of 673 K (400 °C), roasting time of 100 minutes, CuO amount of 34.54 mass pct, and N2 flow rate of 30 mL/min, 91.50 pct arsenic and only 8.63 pct antimony go into the smoke.

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

    KAUST Repository

    Buchholcz, Balázs

    2017-02-06

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

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

    Directory of Open Access Journals (Sweden)

    Bruna Pinheiro Silveira

    2003-07-01

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

  14. Thyroid hormones and iodide in the near-term pregnant rat.

    NARCIS (Netherlands)

    Versloot, P.M.

    1998-01-01

    Thyroid hormones, thyroxine (T4) and 3,5,3'-triiodothyronine (T3), are produced by the thyroid gland. To synthesize thyroid hormones the thyroid needs iodide. The uptake of iodide as well as the production and secretion of T4 and T3 by the thyroid gland is regulated by thyrotropin (TSH), which is pr

  15. Effects of radiation and temperature on iodide sorption by surfactant-modified bentonite.

    Science.gov (United States)

    Choung, Sungwook; Kim, Minkyung; Yang, Jung-Seok; Kim, Min-Gyu; Um, Wooyong

    2014-08-19

    Bentonite, which is used as an engineered barrier in geological repositories, is ineffective for sorbing anionic radionuclides because of its negatively charged surface. This study modified raw bentonite using a cationic surfactant (i.e., hexadecyltrimethylammonium [HDTMA]-Br) to improve its sorption capability for radioactive iodide. The effects of temperature and radiation on the iodide sorption of surfactant-modified bentonite (SMB) were also evaluated under alkaline pH condition similar to that found in repository environments. Different amounts of surfactant, equivalent to the 50, 100, and 200% cation-exchange capacity of the bentonite, were used to produce the HDTMA-SMB for iodide sorption. The sorption reaction of the SMB with iodide reached equilibrium rapidly within 10 min regardless of temperature and radiation conditions. The rate of iodide sorption increased as the amount of the added surfactant was increased and nonlinear sorption behavior was exhibited. However, high temperature and γ-irradiation ((60)Co) resulted in significantly (∼2-10 times) lower iodide Kd values for the SMB. The results of FTIR, NMR, and XANES spectroscopy analysis suggested that the decrease in iodide sorption may be caused by weakened physical electrostatic force between the HDTMA and iodide, and by the surfactant becoming detached from the SMB during the heating and irradiation processes.

  16. Tungstosilicic Acid: An Efficient and Ecofriendly Catalyst for the Conversion of Alcohols to Alkyl Iodides

    Directory of Open Access Journals (Sweden)

    Masoud Mokhtary

    2011-01-01

    Full Text Available Treatment of a range of benzylic, allylic, and secondary aliphatic alcohols with potassium iodides in the presence of H4SiW12O40 affords the corresponding alkyl iodides in good to excellent yield with straightforward purification at room temperature in CH3CN.

  17. Bibenzimidazole containing mixed ligand cobalt(III) complex as a selective receptor for iodide

    Digital Repository Service at National Institute of Oceanography (India)

    Indumathy, R.; Parameswarana, P.S.; Aiswarya, C.V.; Nair, B.U.

    -, OH- and OAc- do not bring about any dramatic visual colorimetric changes. However, metallo-receptor 2 brings about vivid color change with iodide anion visually and this could be due to charge transfer transition via ion pair formation with iodide ion...

  18. CuI-catalyzed Synthesis of Aryl Thiocyanates from Aryl Iodides

    Institute of Scientific and Technical Information of China (English)

    Ye Feng WANG; Yuan ZHOU; Jia Rui WANG; Lei LIU; Qing Xiang GUO

    2006-01-01

    An operationally simple and inexpensive catalyst system was developed for the cross coupling of potassium thiocyanate with aryl iodides by using CuI as catalyst, 1, 10-phenanthroline as ligand, and tetraethylammonium iodide as activator. The procedure is applicable for the synthesis of diverse aryl thiocyanates without any exotic, poisonous reagents.

  19. Leishmania panamensis infection and antimonial drugs modulate expression of macrophage drug transporters and metabolizing enzymes: impact on intracellular parasite survival

    Science.gov (United States)

    Gómez, Maria Adelaida; Navas, Adriana; Márquez, Ricardo; Rojas, Laura Jimena; Vargas, Deninson Alejandro; Blanco, Victor Manuel; Koren, Roni; Zilberstein, Dan; Saravia, Nancy Gore

    2014-01-01

    Objectives Treatment failure is multifactorial. Despite the importance of host cell drug transporters and metabolizing enzymes in the accumulation, distribution and metabolism of drugs targeting intracellular pathogens, their impact on the efficacy of antileishmanials is unknown. We examined the contribution of pharmacologically relevant determinants in human macrophages in the antimony-mediated killing of intracellular Leishmania panamensis and its relationship with the outcome of treatment with meglumine antimoniate. Methods Patients with cutaneous leishmaniasis who failed (n = 8) or responded (n = 8) to treatment were recruited. Gene expression profiling of pharmacological determinants in primary macrophages was evaluated by quantitative RT–PCR and correlated to the drug-mediated intracellular parasite killing. Functional validation was conducted through short hairpin RNA gene knockdown. Results Survival of L. panamensis after exposure to antimonials was significantly higher in macrophages from patients who failed treatment. Sixteen macrophage drug-response genes were modulated by infection and exposure to meglumine antimoniate. Correlation analyses of gene expression and intracellular parasite survival revealed the involvement of host cell metallothionein-2A and ABCB6 in the survival of Leishmania during exposure to antimonials. ABCB6 was functionally validated as a transporter of antimonial compounds localized in both the cell and phagolysosomal membranes of macrophages, revealing a novel mechanism of host cell-mediated regulation of intracellular drug exposure and parasite survival within phagocytes. Conclusions These results provide insight into host cell mechanisms regulating the intracellular exposure of Leishmania to antimonials and variations among individuals that impact parasite survival. Understanding of host cell determinants of intracellular pharmacokinetics/pharmacodynamics opens new avenues to improved drug efficacy for intracellular

  20. Determination of Trace Iodide in Sodium Bisulfite Aqueous Solution by Ion Chromatography with UV Detection

    Energy Technology Data Exchange (ETDEWEB)

    Park, Y.S.; Kim, D.Y.; Choi, K.S.; Park, S.D.; Han, S.H. [Korea Atomic Energy Research Institute, Taejon (Korea)

    2000-06-01

    The iodide was recovered from a simulated spent fuel to the sodium bisulfite aqueous solution. It was discussed that the trace iodide (below 1 ppm) was determined without the matrix effect of 0.1 M sodium bisulfite and 1 mM HNO{sub 3} in aqueous solution by ion chromatography with UV detection. AS4A-SC(DIONEX) column and UV-absorption spectrophotometer were used. The UV-absorption spectra of sodium bisulfite nitric acid and iodide were obtained, and then 230 nm was selected as an absorption wavelength for iodide determination. 0.1 M NaCl eluent was optimum condition. In this condition the calibration curve of iodide was obtained on the range of about 0-1,000 ppb. The linear coefficient was 0.99993 and the detection limit was 5 ppb. The relative standard deviation was 1.26%. (author). 17 refs., 3 tabs., 4 figs.

  1. The Determination of Iodide Based on a Flow-injection Coupling Irreversible Biamperometry

    Institute of Scientific and Technical Information of China (English)

    Li Jun LI; Hao CHENG; Wen Yi HUANG; Hong Xing KONG; Jian Ling WU; Jian Ping LU; Wei GAO; Jun Feng SONG

    2005-01-01

    A novel flow-injection irreversible biamperometric method is described for the direct determination of iodide. The method is based on electrochemical oxidation of iodide at the gold electrode and the reduction of permanganate at the platinum electrode to form an irreversible biamperometric detection system. Under the applied potential difference of 0 V, in the 0.05mol/L sulfuric acid, iodide can be determined over the range 4.00×10-7-l.00×l0-5 mol/L with a sampling frequency of 120 samples per hour. The detection limit for Ⅰ- is 3.0× 10-7 mol/L and the RSD for 40 replicate determinations of 4.0×10-5 mol/L potassium iodide is 1.68%. The new method was applied to the analysis of iodide in table salt with satisfactory results.

  2. Synthesis, growth, structural, thermal, optical properties of new metal-organic crystals: Methyltriphenylphosphonium iodide thiourea and methyltriphenylphosphonium iodide chloroform hemisolvate

    Science.gov (United States)

    Shivachev, Boris L.; Kossev, Krassimir; Dimowa, Louiza T.; Yankov, Georgi; Petrov, Todor; Nikolova, Rositsa P.; Petrova, Nadia

    2013-08-01

    Crystals of methyltriphenylphosphonium iodide thiourea (1) and methyltriphenylphosphonium iodide chloroform hemisolvate (2) were obtained for the first time. Fourier transform infrared (FTIR) spectral studies have been performed to identify the functional groups. Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) were used to study their thermal properties. The optical transmittance window and the lower cutoff wavelength have been identified by UV-vis studies. Crystals of the title compounds suitable for single crystal X-ray analyses were successfully grown by slow evaporation and diffraction data were collected to elucidate the molecular structure and interactions. The proton donors (phosphonium) and proton acceptor (iodine) in the structure of 1 provide infrastructure to introduce charge asymmetry while in 2 chloroform molecule is not involved in the charge transfer. An optical quality crystal of 1 (5×4×2 mm3) was obtained by macroseeding. The crystal has developed facets with major ones (001) and (00¯1). A crystal of 1 was tested with 1060 nm laser radiation and showed second harmonic generation (SHG).

  3. Fabrication of Efficient Low-Bandgap Perovskite Solar Cells by Combining Formamidinium Tin Iodide with Methylammonium Lead Iodide

    Energy Technology Data Exchange (ETDEWEB)

    Liao, Weiqiang; Zhao, Dewei; Yu, Yue; Shrestha, Niraj; Ghimire, Kiran; Grice, Corey R.; Wang, Changlei; Xiao, Yuqing; Cimaroli, Alexander J.; Ellingson, Randy J.; Podraza, Nikolas J.; Zhu, Kai; Xiong, Ren-Gen; Yan, Yanfa

    2016-09-28

    Mixed tin (Sn)-lead (Pb) perovskites with high Sn content exhibit low bandgaps suitable for fabricating the bottom cell of perovskite-based tandem solar cells. In this work, we report on the fabrication of efficient mixed Sn-Pb perovskite solar cells using precursors combining formamidinium tin iodide (FASnI3) and methylammonium lead iodide (MAPbI3). The best-performing cell fabricated using a (FASnI3)0.6(MAPbI3)0.4 absorber with an absorption edge of ~1.2 eV achieved a power conversion efficiency (PCE) of 15.08 (15.00)% with an open-circuit voltage of 0.795 (0.799) V, a short-circuit current density of 26.86(26.82) mA/cm2, and a fill factor of 70.6(70.0)% when measured under forward (reverse) voltage scan. The average PCE of 50 cells we have fabricated is 14.39 +/- 0.33%, indicating good reproducibility.

  4. Horizontal Ampoule Growth and Characterization of Mercuric Iodide at Controlled Gas Pressures for X-Ray and Gamma Ray Spectrometers

    Energy Technology Data Exchange (ETDEWEB)

    McGregor, Douglas S. [Kansas State Univ., Manhattan, KS (United States). Semiconductor Materials and Radiological Technologies Lab., Dept. of Nuclear and Mechanical Engineering; Ariesanti, Elsa [Kansas State Univ., Manhattan, KS (United States). Semiconductor Materials and Radiological Technologies Lab., Dept. of Nuclear and Mechanical Engineering; Corcoran, Bridget [Kansas State Univ., Manhattan, KS (United States). Semiconductor Materials and Radiological Technologies Lab., Dept. of Nuclear and Mechanical Engineering

    2004-04-30

    The project developed a new method for producing high quality mercuric iodide crystals of x-ray and gamma spectrometers. Included are characterization of mercuric iodide crystal properties as a function of growth environment and fabrication and demonstration of room-temperature-operated high-resolution mercuric iodide spectrometers.

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

    Directory of Open Access Journals (Sweden)

    Samanta Etel Treiger Borborema

    2013-08-01

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

  6. Species-specific antimonial sensitivity in Leishmania is driven by post-transcriptional regulation of AQP1.

    Directory of Open Access Journals (Sweden)

    Goutam Mandal

    2015-02-01

    Full Text Available Leishmania is a digenetic protozoan parasite causing leishmaniasis in humans. The different clinical forms of leishmaniasis are caused by more than twenty species of Leishmania that are transmitted by nearly thirty species of phlebotomine sand flies. Pentavalent antimonials (such as Pentostam or Glucantime are the first line drugs for treating leishmaniasis. Recent studies suggest that pentavalent antimony (Sb(V acts as a pro-drug, which is converted to the more active trivalent form (Sb(III. However, sensitivity to trivalent antimony varies among different Leishmania species. In general, Leishmania species causing cutaneous leishmaniasis (CL are more sensitive to Sb(III than the species responsible for visceral leishmaniasis (VL. Leishmania aquaglyceroporin (AQP1 facilitates the adventitious passage of antimonite down a concentration gradient. In this study, we show that Leishmania species causing CL accumulate more antimonite, and therefore exhibit higher sensitivity to antimonials, than the species responsible for VL. This species-specific differential sensitivity to antimonite is directly proportional to the expression levels of AQP1 mRNA. We show that the stability of AQP1 mRNA in different Leishmania species is regulated by their respective 3'-untranslated regions. The differential regulation of AQP1 mRNA explains the distinct antimonial sensitivity of each species.

  7. Species-Specific Antimonial Sensitivity in Leishmania Is Driven by Post-Transcriptional Regulation of AQP1

    Science.gov (United States)

    Mandal, Goutam; Mandal, Srotoswati; Sharma, Mansi; Charret, Karen Santos; Papadopoulou, Barbara; Bhattacharjee, Hiranmoy; Mukhopadhyay, Rita

    2015-01-01

    Leishmania is a digenetic protozoan parasite causing leishmaniasis in humans. The different clinical forms of leishmaniasis are caused by more than twenty species of Leishmania that are transmitted by nearly thirty species of phlebotomine sand flies. Pentavalent antimonials (such as Pentostam or Glucantime) are the first line drugs for treating leishmaniasis. Recent studies suggest that pentavalent antimony (Sb(V)) acts as a pro-drug, which is converted to the more active trivalent form (Sb(III)). However, sensitivity to trivalent antimony varies among different Leishmania species. In general, Leishmania species causing cutaneous leishmaniasis (CL) are more sensitive to Sb(III) than the species responsible for visceral leishmaniasis (VL). Leishmania aquaglyceroporin (AQP1) facilitates the adventitious passage of antimonite down a concentration gradient. In this study, we show that Leishmania species causing CL accumulate more antimonite, and therefore exhibit higher sensitivity to antimonials, than the species responsible for VL. This species-specific differential sensitivity to antimonite is directly proportional to the expression levels of AQP1 mRNA. We show that the stability of AQP1 mRNA in different Leishmania species is regulated by their respective 3’-untranslated regions. The differential regulation of AQP1 mRNA explains the distinct antimonial sensitivity of each species. PMID:25714343

  8. 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.

  9. Morphological effects in the quantum yield of cesium iodide

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, J. [Ecole Politechnique Federale, Lausanne (Switzerland). DP-IPA PH-Ecublens; Barbo, F. [Sincrotrone Trieste SpA, Padriciano 99, 34012 Trieste (Italy); Bertolo, M. [Sincrotrone Trieste SpA, Padriciano 99, 34012 Trieste (Italy); Bianco, A. [Sincrotrone Trieste SpA, Padriciano 99, 34012 Trieste (Italy); Braem, A. [European Organization for Nuclear Research, Geneva (Switzerland). Div. Particle Physics Experiments; Cerasari, S. [Sincrotrone Trieste SpA, Padriciano 99, 34012 Trieste (Italy); Coluzza, C. [Ecole Politechnique Federale, Lausanne (Switzerland). DP-IPA PH-Ecublens; Dell`Orto, T. [Ecole Politechnique Federale, Lausanne (Switzerland). DP-IPA PH-Ecublens; Fontana, S. [Sincrotrone Trieste SpA, Padriciano 99, 34012 Trieste (Italy); Margaritondo, G. [Ecole Politechnique Federale, Lausanne (Switzerland). DP-IPA PH-Ecublens; Nappi, E. [Istituto Nazionale di Fisica Nucleare, Bari (Italy); Paic, G. [European Organization for Nuclear Research, Geneva (Switzerland). Div. Particle Physics Experiments; Piuz, F. [European Organization for Nuclear Research, Geneva (Switzerland). Div. Particle Physics Experiments; Sanjines, R. [Ecole Politechnique Federale, Lausanne (Switzerland). DP-IPA PH-Ecublens; Scognetti, T. [Istituto Nazionale di Fisica Nucleare, Bari (Italy); Sgobba, S. [European Organization for Nuclear Research, Geneva (Switzerland). Div. Particle Physics Experiments

    1995-07-15

    We demonstrated that polycrystalline cesium iodide (CsI) on large area Ni/Au coated printed board provides a quantum efficiency (QE) higher by a factor of 2 than the films deposited on the standard Cu/Au printed circuits. This is the most important result of the present systematic study of the QE lateral inhomogeneity for CsI on different substrates. We found a strong correlation between the QE lateral variation and the morphological homogeneity of the films. The QE was measured by UV photoelectron emission microscopy and spatially resolved X-ray photoemission, and the morphology studies were performed by secondary electron microscopy, X-ray diffraction and scanning tunneling microscopy. (orig.).

  10. Electronic characterization of mercuric iodide gamma ray spectrometers

    Energy Technology Data Exchange (ETDEWEB)

    Gerrish, V.M.

    1993-01-01

    During the past four years the yield of high resolution mercuric iodide (HgI[sub 2]) gamma ray spectrometers produced at EG G/EM has increased dramatically. Data is presented which demonstrates a strong correlation between starting material and spectrometer performance. Improved spectrometer yields are attributed to the method of HgI[sub 2] synthesis and to material purification procedures. Data is presented which shows that spectrometer performance is correlated with hole mobility-lifetime products. In addition, the measurement of Schottky barrier heights on HgI[sub 2] spectrometers has been performed using I-V curves and the photoelectric method. Barrier heights near 1.1 eV have been obtained using various contacts and contact deposition methods. These data suggest the pinning of the Fermi level at midgap at the HgI[sub 2] surface, probably due to surface states formed prior to contact deposition.

  11. Electronic characterization of mercuric iodide gamma ray spectrometers

    Energy Technology Data Exchange (ETDEWEB)

    Gerrish, V.M.

    1993-06-01

    During the past four years the yield of high resolution mercuric iodide (HgI{sub 2}) gamma ray spectrometers produced at EG&G/EM has increased dramatically. Data is presented which demonstrates a strong correlation between starting material and spectrometer performance. Improved spectrometer yields are attributed to the method of HgI{sub 2} synthesis and to material purification procedures. Data is presented which shows that spectrometer performance is correlated with hole mobility-lifetime products. In addition, the measurement of Schottky barrier heights on HgI{sub 2} spectrometers has been performed using I-V curves and the photoelectric method. Barrier heights near 1.1 eV have been obtained using various contacts and contact deposition methods. These data suggest the pinning of the Fermi level at midgap at the HgI{sub 2} surface, probably due to surface states formed prior to contact deposition.

  12. Dual frequency cavitation event sensor with iodide dosimeter.

    Science.gov (United States)

    Ebrahiminia, Ali; Mokhtari-Dizaji, Manijhe; Toliyat, Tayebeh

    2016-01-01

    The inertial cavitation activity depends on the sonication parameters. The purpose of this work is development of dual frequency inertial cavitation meter for therapeutic applications of ultrasound waves. In this study, the chemical effects of sonication parameters in dual frequency sonication (40 kHz and 1 MHz) were investigated in the progressive wave mode using iodide dosimetry. For this purpose, efficacy of different exposure parameters such as intensity, sonication duration, sonication mode, duty factor and net ultrasound energy on the inertial cavitation activity have been studied. To quantify cavitational effects, the KI dosimeter solution was sonicated and its absorbance at a wavelength of 350 nm was measured. The absorbance values in continuous sonication mode was significantly higher than the absorbance corresponding to the pulsed mode having duty factors of 20-80% (plevel intensity (sensor can be useful for ultrasonic treatments.

  13. Development of mercuric iodide detectors for XAS and XRD measurements

    Energy Technology Data Exchange (ETDEWEB)

    Warburton, W.K.; Iwanczyk, J.S.; Dabrowski, A.J.; Hedman, B.; Penner-Hakn, J.E.; Roe, A.L.; Hodgson, K.O.; Beyerle, A.

    1985-07-01

    A prototype element for an energy dispersive detector (EDD) array was constructed using a Mercuric Iodide detector. Both detector and front end FET could be thermoelectrically cooled. Tested at SSRL, the detector had 250 eV electronic noise and 315 eV resolution at 5.9 keV. K line fluorescence spectra were collected for selected elements between Cl (2622 eV) and Zn (8638 eV). Count rate capability to 60,000 cps was demonstrated. Several detector parameters were measured, including energy linearity, resolution vs. shaping time, and detector dead time. An EXAFS (extended x-ray absorption fine structure) spectrum was recorded and compared to simultaneously collected transmission data.

  14. Radiative efficiency of lead iodide based perovskite solar cells

    Science.gov (United States)

    Tvingstedt, Kristofer; Malinkiewicz, Olga; Baumann, Andreas; Deibel, Carsten; Snaith, Henry J.; Dyakonov, Vladimir; Bolink, Henk J.

    2014-08-01

    The maximum efficiency of any solar cell can be evaluated in terms of its corresponding ability to emit light. We herein determine the important figure of merit of radiative efficiency for Methylammonium Lead Iodide perovskite solar cells and, to put in context, relate it to an organic photovoltaic (OPV) model device. We evaluate the reciprocity relation between electroluminescence and photovoltaic quantum efficiency and conclude that the emission from the perovskite devices is dominated by a sharp band-to-band transition that has a radiative efficiency much higher than that of an average OPV device. As a consequence, the perovskite have the benefit of retaining an open circuit voltage ~0.14 V closer to its radiative limit than the OPV cell. Additionally, and in contrast to OPVs, we show that the photoluminescence of the perovskite solar cell is substantially quenched under short circuit conditions in accordance with how an ideal photovoltaic cell should operate.

  15. 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...

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

    Directory of Open Access Journals (Sweden)

    Meiri Vanderlei Nogueira de Lima

    2007-06-01

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

  17. Development of w/o microemulsion for transdermal delivery of iodide ions.

    Science.gov (United States)

    Lou, Hao; Qiu, Ni; Crill, Catherine; Helms, Richard; Almoazen, Hassan

    2013-03-01

    The objective of this study was to develop a water-in-oil (w/o) microemulsion which can be utilized as a transdermal delivery for iodide ions. Several w/o microemulsion formulations were prepared utilizing Span 20, ethanol, Capryol 90®, and water. The selected formulations had 5%, 10%, 15%, 20%, and a maximum of 23% w/w water content. Potassium iodide (KI) was incorporated in all formulations at 5% w/v. Physicochemical characterizations were conducted to evaluate the structure and stability. These studies included: mean droplet size, pH, viscosity, conductivity, and chemical stability tests. In vitro human skin permeation studies were conducted to evaluate the diffusion of the iodide ion through human skin. The w/o microemulsion formulations were stable and compatible with iodide ions with water content ranging from 5% to 23% w/w. The addition of KI influenced the physicochemical properties of microemulsion as compared to blank microemulsion formulations. In vitro human skin permeation studies indicated that selected formulations improved iodide ion diffusion significantly as compared to control (KI solution; P valueIodide ions were entrapped within the aqueous core of w/o microemulsion. Span 20, ethanol and Capryol 90 protected the iodide ions against oxidation and formed a stable microemulsion. It is worth to note that according to Hofmeister series, iodide ions tend to lower the interfacial tension between water and oil and consequently enhance overall stability. This work illustrates that microemulsion system can be utilized as a vehicle for the transdermal administration of iodide.

  18. 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

  19. Evaluation of antimony efficiency on nickel passivation in PETROBRAS refineries; Avaliacao da efetividade do antimonio para passivacao de niquel nas refinarias da PETROBRAS

    Energy Technology Data Exchange (ETDEWEB)

    Cerqueira, Henrique Soares; Pimenta, Ricardo Drolhe M. [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas. Setor de Pesquisa, Desenvolvimento e Engenharia de Abastecimento]. E-mail: henriquecerqueira@cenpes.petrobras.com.br; Baugis, Guintar Luciano; Tan, Mauricio Hoansan [PETROBRAS, Maua, SP (Brazil). Refinaria de Capuava (RECAP)

    2001-12-01

    In the present paper, a brief review concerning the use of antimony as nickel passivator is presented. X-ray fluorescence analysis of equilibrium catalysts from several fluid catalytic cracking units in Petrobras refineries indicates that the Sb/ Ni ratio currently in use is very low (approx. 0.1) and that neither the coke nor the gas factor obtained in laboratory tests (MAT) are correlated with eh Sb/Ni ratio. An experiment in the cyclic deactivation unit doping the feedstock (GOP cabiunas) with Ni, V naphthenates as well as antimony, aiming at simulating the levels found in PETROBRAS refineries, showed that under those conditions the antimony does not deposit significantly over the catalyst. Analysis of antimony content in the catalyst fines and decanted oil from one FCC unit confirms the non-retention of antimony under the applied industrial conditions. (author)

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

    Directory of Open Access Journals (Sweden)

    H. Barangizi

    2010-08-01

    Full Text Available 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 without P (0, 3 mgL-1, and three concentrations of NaCl (0, 60, 120 mM in three replications was conducted. After 40 days, plants were harvested and the roots and shoots were separated. Increasing Sb concentrations, significantly reduced shoot weight. In the presence of Sb, shoot wet and dry matter increased with phosphorous addition because of the positive effect of phosphorous. Increasing Sb concentration with the same level of phosphorous produced plants with less fresh matter. Roots with lower phosphorous level had higher permeability, and increasing phosphorous concentration had a significant effect on root permeability. The highest and lowest root permeability was related to blank Sb level and 6 mg L-1 level of Sb, respectively. Increasing Sb concentration in nutrient solution first reduced and then significantly increased the root permeability. Root permeability also increased significantly by increasing salinity level in nutrient solution. Root Fe concentration of blank phosphorous level was about 13 percent higher than 3 mg L-1 of phosphorous but there was no significant difference in root Fe concentration between species in nutrient solutions with different levels of Sb and NaCl concentrations. The addition of Sb decreased root Zn concentration.

  1. 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.

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

    Directory of Open Access Journals (Sweden)

    Franco AMR

    2016-12-01

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

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

    Science.gov (United States)

    Turner, Andrew; Filella, Montserrat

    2017-02-09

    Very little systematic information exists on the occurrence and concentrations of antimony (Sb) in consumer products. In this study, a Niton XL3t field-portable-X-ray fluorescence (FP-XRF) spectrometer was deployed in situ and in the laboratory to provide quantitative information on Sb dissipated in plastic items and fixtures (including rubber, textile and foamed materials) from the domestic, school, vehicular and office settings. The metalloid was detected in 18% of over 800 measurements performed, with concentrations ranging from about 60 to 60,000μgg(-1). The highest concentrations were encountered in white, electronic casings and in association with similar concentrations of Br, consistent with the use of antimony oxides (e.g. Sb2O3) as synergistic flame retardants. Concentrations above 1000μgg(-1), and with or without Br, were also encountered in paints, piping and hosing, adhesives, whiteboards, Christmas decorations, Lego blocks, document carriers, garden furniture, upholstered products and interior panels of private motor vehicles. Lower concentrations of Sb were encountered in a wide variety of items but its presence (without Br) in food tray packaging, single-use drinks bottles, straws and small toys were of greatest concern from a human health perspective. While the latter observations are consistent with the use of antimony compounds as catalysts in the production of polyethylene terephthalate, co-association of Sb and Br in many products not requiring flame retardancy suggests that electronic casings are widely recycled. Further research is required into the mobility of Sb when dissipated in new, recycled and aged polymeric materials.

  4. 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

  5. Antimony film sensor for sensitive rare earth metal analysis in environmental samples.

    Science.gov (United States)

    Makombe, Martin; van der Horst, Charlton; Silwana, Bongiwe; Iwuoha, Emmanuel; Somerset, Vernon

    2016-07-02

    A sensor for the adsorptive stripping voltammetric determination of rare earth elements has been developed. The electrochemical procedure is based on the oxidation of the rare earth elements complexed with alizarin complexone at a glassy carbon electrode that was in situ modified with an antimony film, during an anodic scan from -0.2 V to 1.1 V (vs. Ag/AgCl) and deposition potential of -0.1 V (vs. Ag/AgCl). The factors influencing the adsorptive stripping capability were optimised, including the complexing agent concentration, plating concentration of antimony and deposition time. The detection of rare earth elements (La, Ce and Pr) were realised in 0.08 M sodium acetate (pH = 5.8) solution as supporting electrolyte, with 2 × 10(-6) M alizarin complexone and 1.0 mg L(-1) antimony solution. Under the optimised conditions, a deposition time of 360 s was obtained and a linear response was observed between 1 and 25 µg L(-1). The reproducibility of the voltammetric measurements was found to be within 5.0% RSD for 12 replicate measurements of cerium(III) concentration of 5 µg L(-1) using the same electrode surface. The detection limits obtained using stripping analysis was 0.06, 0.42 and 0.71 μg L(-1) for Ce(III), La(III) and Pr(III), respectively. The developed sensor has been successfully applied for the determination of cerium, lanthanum and praseodymium in municipal tap water samples.

  6. Sm-Nd isotope dating of hydrothermal calcites from the Xikuangshan antimony deposit, Central Hunan

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The research on Samarium-Neodymium isotope systematics of hydrothermal calcites from the Xikuangshan antimony deposit, Central Hunan, places precise timing constraints on the Sb mineralization in this area. It is revealed that the Xikuangshan deposit formed during the late Jurassic-early Cretaceous Period, the early- and late- stage mineralization took place at (155.5 ± 1.1) Ma and (124.1 ± 3.7) Ma, respectively. The accurate age determination of mineralization is very crucial for revealing the super-enrichment mechanism of the element Sb at the Xikuangshan mine, and lays some foundations for the further understandings of its ore genesis and mineralization mechanism.

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

    Directory of Open Access Journals (Sweden)

    RAKSHIT AMETA

    2011-07-01

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

  8. 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.

  9. Determination of antimony in rain water at the nanogram level with surfactant and brilliant green

    Energy Technology Data Exchange (ETDEWEB)

    Tripathi, A.N.; Patel, K.S. [School of Studies in Chemistry, Pt. Ravishankar University, Raipur (India)

    1998-01-01

    A new, simple, selective and sensitive method for the spectrophotometric determination of antimony in rain water is described. It includes preconcentrating Sb with surfactants (i.e. cetylpyridinium chloride (CPC) and Triton X-100 (TX-100)) into toluene and allowing the extract to react with a dye, i.e. brilliant green (BG). The value of apparent molar absorptivity is 5.55 x 10{sup 5} L-mol{sup -1} . cm{sup -1} at {lambda}{sub max} = 620 nm; the detection limit is 3 ng/mL Sb in rain water at 3-fold preconcentration. (orig.) With 1 fig., 2 tabs., 7 refs.

  10. Temperature dependent electrical resistivity of gallium and antimony in a liquid form

    Science.gov (United States)

    Prajapati, A. V.; Sonvane, Y. A.; Thakor, P. B.

    2016-05-01

    Present paper deals with the effects of temperature variation on the electrical resistivity (Ω) of liquid Gallium (Ga), and Antimony (Sb). We have used a new parameter free pseudopotential with a Zeeman formula for finding it. To see the effects of screening Farid et al local field correction function is used with the Charged Hard Sphere (CHS) reference system. Analysis and comparison between the plotted graphs, based on present computed data and other experimental data defines and conclude that our newly constructed model potential is an effective one to produce the data for the temperature dependent electrical resistivity of some liquid semiconductors.

  11. Stripping voltammetric determination of mercury(II) at antimony-coated carbon paste electrode.

    Science.gov (United States)

    Ashrafi, Amir M; Vytřas, Karel

    2011-10-15

    A new procedure was elaborated to determine mercury(II) using an anodic stripping square-wave voltammetry at the antimony film carbon paste electrode (SbF-CPE). In highly acidic medium of 1M hydrochloric acid, voltammetric measurements can be realized in a wide potential window. Presence of cadmium(II) allows to separate peaks of Hg(II) and Sb(III) and apparently catalyses reoxidation of electrolytically accumulated mercury, thus allowing its determination at ppb levels. Calibration dependence was linear up to 100 ppb Hg with a detection limit of 1.3 ppb. Applicability of the method was tested on the real river water sample.

  12. A Direct Transformation of Aryl Aldehydes to Benzyl Iodides Via Reductive Iodination

    Energy Technology Data Exchange (ETDEWEB)

    Ruso, Jayaraman Sembian; Rajendiran, Nagappan; Kumaran, Rajendran Senthil [Univ. of Madras, Chennai (India)

    2014-02-15

    A facile transformation of aryl aldehydes to benzyl iodides through one-pot reductive iodination is reported. This protocol displays remarkable functional group tolerance and the title compound was obtained in good to excellent yield.

  13. Kinetics and mechanism of the mercury(II)-assisted hydrolysis of methyl iodide.

    Science.gov (United States)

    Celo, Valbona; Scott, Susannah L

    2005-04-01

    The kinetics and mechanism of the reaction of aqueous Hg(II) with methyl iodide have been investigated. The overall reaction is best described as Hg(II)-assisted hydrolysis, resulting in quantitative formation of methanol and, in the presence of excess methyl iodide, ultimately, HgI2 via the intermediate HgI+. The kinetics are biexponential when methyl iodide is in excess. At 25 degrees C, the acceleration provided by Hg2+ is 7.5 times greater than that caused by HgI+, while assistance of hydrolysis was not observed for HgI2. Thus, the reactions are not catalytic in Hg(II). The kinetics are consistent with an SN2-M+ mechanism involving electrophilic attack at iodide. As expected, methylation of mercury is not a reaction pathway; traces of methylmercury(II) are artifacts of the extraction/preconcentration procedure used for methylmercury analysis.

  14. Fluorescence characteristics of 5-amino salicylic acid: An iodide recognition study

    Science.gov (United States)

    Arora, Priyanka; Suyal, Kanchan; Joshi, Neeraj K.; Joshi, Hem Chandra; Pant, Sanjay

    In this paper we report the effect of iodide on the fluorescence of 5-amino salicylic acid (5-ASA). In the absence of iodide, prominent blue green (BG) emission band at ˜465 nm (broad) is observed in aprotic solvents whereas violet (V) emission at ˜408 nm, blue green (BG) at ˜480 nm and green (G) at ˜500 nm are observed in case of protic solvents. On the addition of iodide ion (I-), the intensity of BG fluorescence is enhanced in case of aprotic solvents. On the other hand the G band is enhanced in protic solvents and decrease in the intensity of the V band is observed. The effect of hydrogen bonding as well as the interplay of neutral and ionic species is invoked to explain the observed results. The study projects the application of this system in iodide recognition in protic/aprotic environments.

  15. Horseradish Peroxidase-Mediated, Iodide-Catalyzed Cascade Reaction for Plasmonic Immunoassays.

    Science.gov (United States)

    Xianyu, Yunlei; Chen, Yiping; Jiang, Xingyu

    2015-11-01

    This report outlines an enzymatic cascade reaction for signal transduction and amplification for plasmonic immunoassays by using horseradish peroxidase (HRP)-mediated aggregation of gold nanoparticles (AuNPs). HRP-catalyzed oxidation of iodide and iodide-catalyzed oxidation of cysteine is employed to modulate the plasmonic signals of AuNPs. It agrees well with the current immunoassay platforms and allows naked-eye readout with enhanced sensitivity, which holds great promise for applications in resource-constrained settings.

  16. Air-Driven Potassium Iodide-Mediated Oxidative Photocyclization of Stilbene Derivatives.

    Science.gov (United States)

    Matsushima, Tomoya; Kobayashi, Sayaka; Watanabe, Soichiro

    2016-09-02

    A new method has been developed for the potassium iodide-mediated oxidative photocyclization of stilbene derivatives. Compared with conventional iodine-mediated oxidative photocyclization reactions, this new method requires shorter reaction times and affords cyclized products in yields of 45-97%. This reaction proceeds with a catalytic amount of potassium iodide and works in an air-driven manner without the addition of an external scavenger. The radical-mediated oxidative photocyclization of stilbene derivatives using TEMPO was also investigated.

  17. [Study on the stability of potassium iodide of the iodized salt].

    Science.gov (United States)

    Voudouris, E

    1975-04-29

    The stability of potassium iodide in iodized salt has been studied with respect to the purity of the salt used as raw material. It has been found that the iodized salt prepared from high purity salt and preserved under proper conditions (protection from light, humidity and high temperatures) keeps, for several months, the most of the initially added potassium iodide, without any addition of stabilizers, except for a small bicarbonate.

  18. Permeation of iodide from iodine-enriched yeast through porcine intestine.

    Science.gov (United States)

    Ryszka, Florian; Dolińska, Barbara; Zieliński, Michał; Chyra, Dagmara; Dobrzański, Zbigniew

    2013-01-01

    Iodine deficiency is a common phenomenon, threatening the whole global human population. Recommended daily intake of iodine is 150 μg for adults and 250 μg for pregnant and breastfeeding women. About 50% of human population can be at risk of moderate iodine deficiency. Due to this fact, increased iodine supplementation is recommended, through intake of iodized mineral water and salt iodization. The aim of this study was to investigate permeation and absorption of iodide from iodine bioplex (experimental group) in comparison with potassium iodide (controls). Permeation and absorption processes were investigated in vitro using a porcine intestine. The experimental model was based on a standard Franz diffusion cell (FD-Cell). The iodine bioplex was produced using Saccharomyces cerevisiae yeast and whey powder: iodine content - 388 μg/g, total protein - 28.5%, total fat - 0.9%., glutamic acid - 41.2%, asparaginic acid - 29.4%, lysine - 24.8%; purchased from: F.Z.N.P. Biochefa, Sosnowiec, Poland. Potassium iodide was used as controls, at 388 μg iodine concentration, which was the same as in iodine-enriched yeast bioplex. A statistically significant increase in iodide permeation was observed for iodine-enriched yeast bioplex in comparison with controls - potassium iodide. After 5h the total amount of permeated iodide from iodine-enriched yeast bioplex was 85%, which is ~ 2-fold higher than controls - 37%. Iodide absorption was by contrast statistically significantly higher in controls - 7.3%, in comparison with 4.5% in experimental group with iodine-enriched yeast bioplex. Presented results show that iodide permeation process dominates over absorption in case of iodine-enriched yeast bioplex.

  19. Modelling iodide – iodate speciation in atmospheric aerosol: Contributions of inorganic and organic iodine chemistry

    Directory of Open Access Journals (Sweden)

    S. Pechtl

    2007-01-01

    Full Text Available The speciation of iodine in atmospheric aerosol is currently poorly understood. Models predict negligible iodide concentrations but accumulation of iodate in aerosol, both of which is not confirmed by recent measurements. We present an updated aqueous phase iodine chemistry scheme for use in atmospheric chemistry models and discuss sensitivity studies with the marine boundary layer model MISTRA. These studies show that iodate can be reduced in acidic aerosol by inorganic reactions, i.e., iodate does not necessarily accumulate in particles. Furthermore, the transformation of particulate iodide to volatile iodine species likely has been overestimated in previous model studies due to negligence of collision-induced upper limits for the reaction rates. However, inorganic reaction cycles still do not seem to be sufficient to reproduce the observed range of iodide – iodate speciation in atmospheric aerosol. Therefore, we also investigate the effects of the recently suggested reaction of HOI with dissolved organic matter to produce iodide. If this reaction is fast enough to compete with the inorganic mechanism, it would not only directly lead to enhanced iodide concentrations but, indirectly via speed-up of the inorganic iodate reduction cycles, also to a decrease in iodate concentrations. Hence, according to our model studies, organic iodine chemistry, combined with inorganic reaction cycles, is able to reproduce observations. The presented chemistry cycles are highly dependent on pH and thus offer an explanation for the large observed variability of the iodide – iodate speciation in atmospheric aerosol.

  20. Mechanistic aspects of ingested chlorine dioxide on thyroid function: impact of oxidants on iodide metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Bercz, J.P.; Jones, L.L.; Harrington, R.M.; Bawa, R.; Condie, L.

    1986-11-01

    Toxicological studies dealing with recent findings of health effects of drinking water disinfectants are reviewed. Experiments with monkeys and rodents indicate that the biological activity of ingested disinfectants is expressed via their chemical interaction with the mucosal epithelia, secretory products, and nutritional contents of the alimentary tract. Evidence exists that a principal partner of this redox interaction is the iodide of nutritional origin that is ubiquitous in the gastrointestinal tract. Thus the observation that subchronic exposure to chlorine dioxide (ClO/sub 2/) in drinking water decreases serum thyroxine levels in mammalian species can be best explained with changes produced in the chemical form of the bioavailable iodide. Ongoing and previously reported mechanistic studies indicate that oxidizing agents such as chlorine-based disinfectants oxidize the basal iodide content of the gastrointestinal tract. The resulting reactive iodine species readily attaches to organic matter by covalent bonding. Evidence suggests that the extent to which such iodinated organics are formed is proportional to the magnitude of the electromotive force and stoichiometry of the redox couple between iodide and the disinfectant. Because the extent of thyroid uptake of the bioavailable iodide does not decrease during ClO/sub 2/ ingestion, it seems that ClO/sub 2/ does not cause iodide deficiency of sufficient magnitude to account for the decease in hormonogenesis. Absorption of one or more of iodinated molecules, e.g., nutrient, hormones, or cellular constituents of the alimentary tract having thyromimetic or thyroid inhibitory properties, is a better hypothesis for the effects seen.

  1. Lead iodide X-ray and gamma-ray spectrometers for room and high temperature operation

    Energy Technology Data Exchange (ETDEWEB)

    Hermon, H.; James, R.B.; Cross, E. [and others

    1997-02-01

    In this study, we report on the results of the investigation of lead iodide material properties. The effectiveness of zone refining purification methods on the material purity is determined by ICP-MS and ICP-OES and correlated to the electrical and physical material properties. We show that this zone refining method is very efficient in removing impurities from lead iodide and we also determine the segregation coefficient for some of these impurities. Triple axis x- ray diffraction (TAD) analysis has been used to determine the crystalline perfection of the lead iodide after applying various cutting, etching, and fabrication methods. The soft lead iodide crystal was found to be damaged when cleaved by a razor blade, but by using a diamond wheel saw, followed by etching, the crystallinity of the material was improved, as observed by TAD. Low temperature photoluminescence also indicates an improvement in the material properties of the purified lead iodide. Electrical properties of lead iodide such as carrier mobility, were calculated based on carrier- phonon scattering. The results for the electrical properties were in good agreement with the experimental data.

  2. Critical evaluation of acetylthiocholine iodide and acetylthiocholine chloride as substrates for amperometric biosensors based on acetylcholinesterase.

    Science.gov (United States)

    Bucur, Madalina-Petruta; Bucur, Bogdan; Radu, Gabriel-Lucian

    2013-01-25

    Numerous amperometric biosensors have been developed for the fast analysis of neurotoxic insecticides based on inhibition of cholinesterase (AChE). The analytical signal is quantified by the oxidation of the thiocholine that is produced enzymatically by the hydrolysis of the acetylthiocholine pseudosubstrate. The pseudosubstrate is a cation and it is associated with chloride or iodide as corresponding anion to form a salt. The iodide salt is cheaper, but it is electrochemically active and consequently more difficult to use in electrochemical analytical devices. We investigate the possibility of using acetylthiocholine iodide as pseudosubstrate for amperometric detection. Our investigation demonstrates that operational conditions for any amperometric biosensor that use acetylthiocholine iodide must be thoroughly optimized to avoid false analytical signals or a reduced sensitivity. The working overpotential determined for different screen-printed electrodes was: carbon-nanotubes (360 mV), platinum (560 mV), gold (370 mV, based on a catalytic effect of iodide) or cobalt phthalocyanine (110 mV, but with a significant reduced sensitivity in the presence of iodide anions).

  3. 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.

  4. Effect of indium and antimony doping in SnS single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Chaki, Sunil H., E-mail: sunilchaki@yahoo.co.in; Chaudhary, Mahesh D.; Deshpande, M.P.

    2015-03-15

    Highlights: • Single crystals growth of pure SnS, indium doped SnS and antimony doped SnS by direct vapour transport (DVT) technique. • Doping of In and Sb occurred in SnS single crystals by cation replacement. • The replacement mechanism ascertained by EDAX, XRD and substantiated by Raman spectra analysis. • Dopants concentration affects the optical energy bandgap. • Doping influences electrical transport properties. - Abstract: Single crystals of pure SnS, indium (In) doped SnS and antimony (Sb) doped SnS were grown by direct vapour transport (DVT) technique. Two doping concentrations of 5% and 15% each were employed for both In and Sb dopants. Thus in total five samples were studied viz., pure SnS (S1), 5% In doped SnS (S2), 15% In doped SnS (S3), 5% Sb doped SnS (S4) and 15% Sb doped SnS (S5). The grown single crystal samples were characterized by evaluating their surface microstructure, stoichiometric composition, crystal structure, Raman spectroscopy, optical and electrical transport properties using appropriate techniques. The d.c. electrical resistivity and thermoelectric power variations with temperature showed semiconducting and p-type nature of the as-grown single crystal samples. The room temperature Hall Effect measurements further substantiated the semiconducting and p-type nature of the as-grown single crystal samples. The obtained results are deliberated in detail.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Stability and electronic properties of two-dimensional indium iodide

    Science.gov (United States)

    Wang, Jizhang; Dong, Baojuan; Guo, Huaihong; Yang, Teng; Zhu, Zhen; Hu, Gan; Saito, Riichiro; Zhang, Zhidong

    2017-01-01

    Based on ab initio density functional calculations, we studied the stability and electronic properties of two-dimensional indium iodide (InI). The calculated results show that monolayer and few-layer InI can be as stable as its bulk counterpart. The stability of the monolayer structure is further supported by examining the electronic and dynamic stability. The interlayer interaction is found to be fairly weak (˜160 meV/atom) and mechanical exfoliation to obtain monolayer and few-layer structures will be applicable. A direct band gap of 1.88 eV of the bulk structure is obtained from the hybrid functional method, and is comparable to the experimental one (˜2.00 eV). The electronic structure can be tuned by layer stacking and external strain. The size of the gap is a linear function of an inverse number of layers, suggesting that we can design few-layer structures for optoelectronic applications in the visible optical range. In-plane tensile or hydrostatic compressive stress is found to be useful not only in varying the gap size to cover the whole visible optical range, but also in inducing a semiconductor-metal transition with an experimentally accessible stress. The present result strongly supports the strategy of broadening the scope of group-V semiconductors by looking for isoelectronic III-VII atomic-layered materials.

  14. Persistent photovoltage in methylammonium lead iodide perovskite solar cells

    Science.gov (United States)

    Baumann, A.; Tvingstedt, K.; Heiber, M. C.; Väth, S.; Momblona, C.; Bolink, H. J.; Dyakonov, V.

    2014-08-01

    We herein perform open circuit voltage decay (OCVD) measurements on methylammonium lead iodide (CH3NH3PbI3) perovskite solar cells to increase the understanding of the charge carrier recombination dynamics in this emerging technology. Optically pulsed OCVD measurements are conducted on CH3NH3PbI3 solar cells and compared to results from another type of thin-film photovoltaics, namely, the two reference polymer-fullerene bulk heterojunction solar cell devices based on P3HT:PC60BM and PTB7:PC70BM blends. We observe two very different time domains of the voltage transient in the perovskite solar cell with a first drop on a short time scale that is similar to the decay in the studied organic solar cells. However, 65%-70% of the maximum photovoltage persists on much longer timescales in the perovskite solar cell than in the organic devices. In addition, we find that the recombination dynamics in all time regimes are dependent on the starting illumination intensity, which is also not observed in the organic devices. We then discuss the potential origins of these unique behaviors.

  15. Structural Effects on the Bandstructure of Methylammonium Lead Iodide

    Science.gov (United States)

    Bernardi, Marco; Barker, Bradford A.; Vigil-Fowler, Derek; Neaton, Jeffrey B.; Louie, Steven G.; Louie Team

    Metal-organic halide perovskites possess peculiar physical properties. The carrier diffusion length in methylammonium lead iodide (MAPbI) exceeds 1 μm, but this unusually high value for a solution-processed material is poorly understood. We developed first-principles calculations of carrier lifetimes and diffusion lengths in semiconductors, which require accurate knowledge of the bandstructure. In this talk, we show that in MAPbI the structure strongly affects the bandstructure and band edges, and that density functional theory (DFT) is unable to predict the room temperature tetragonal structure due to the polymorphism of MAPbI. The Rashba splitting induced by the spin-orbit interaction, and the DFT band gap and effective masses, all depend strongly on the chosen structure, a point that previous work failed to address. Working with multiple stochastic realizations of large unit cells with random methylammonium orientations, we compute average effective masses and show that the effective mass depends linearly on the band gap. The average Rashba coefficient we find is an order of magnitude smaller than previously reported, and the band edges are almost parabolic. Our structures possess the correct symmetry and are free of the spurious Pb off-centering assumed in previous work. We identify the correct starting point for GW bandstructure calculations and to compute the carrier lifetime and diffusion length.

  16. Chloride, bromide and iodide scintillators with europium doping

    Science.gov (United States)

    Zhuravleva, Mariya; Yang, Kan

    2014-08-26

    A halide scintillator material is disclosed where the halide may comprise chloride, bromide or iodide. The material is single-crystalline and has a composition of the general formula ABX.sub.3 where A is an alkali, B is an alkali earth and X is a halide which general composition was investigated. In particular, crystals of the formula ACa.sub.1-yEu.sub.yI.sub.3 where A=K, Rb and Cs were formed as well as crystals of the formula CsA.sub.1-yEu.sub.yX.sub.3 (where A=Ca, Sr, Ba, or a combination thereof and X=Cl, Br or I or a combination thereof) with divalent Europium doping where 0.ltoreq.y.ltoreq.1, and more particularly Eu doping has been studied at one to ten mol %. The disclosed scintillator materials are suitable for making scintillation detectors used in applications such as medical imaging and homeland security.

  17. 从含锑烟灰中湿法提取立方晶型三氧化二锑%Extraction of Cubic Crystal Antimony Trioxide from Dusts Containing Antimony

    Institute of Scientific and Technical Information of China (English)

    张荣良; 史宝良; 史爱波; 鞠洪博; 姜大伟; 王伟; 颜平

    2011-01-01

    以含锑烟尘为原料,采用HCI浸出-锑粉还原-Na2CO3中和-氨水添加EDTA水解工艺回收立方晶型Sb2O3产品.对回收工艺过程和条件进行了研究.重点探讨了浸出温度、浸出时间、HCI摩尔浓度、浸出液固比对Sb浸出率的影响,以及不同的SbCl3与EDTA摩尔比对产品Sb2O3晶型的影响.结果表明,采用该工艺Sb的浸出率为98.50%,Sb的回收率为90.35%,产品为纯的立方晶型Sb2O3.%With dusts containing antimony as raw material, the cubic crystal antimony trioxide was recovered by the processes including leaching in hydrochloric acid, antimony powder reduction, sodium carbonate-neutralization, and hydrolysis with EDTA as an additive in ammonia.The influences of leaching temperature, leaching time, hydrochloric acid concentrate, and ratio of liquid to solid on the leaching rate of Sb, and the molar ratio of SbCl3 to EDTA on the crystal of the antimony trioxide product were investigated.The results indicated that the leaching rate of Sb was 98.50%, the recovery of Sb was 90.35%, and the purity of product with cubic crystal antimony trioxide was 99.5%.

  18. 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.

  19. Identification of antimony resistance markers in Leishmania tropica field isolates through a cDNA-AFLP approach.

    Science.gov (United States)

    Kazemi-Rad, Elham; Mohebali, Mehdi; Khadem-Erfan, Mohammad Bagher; Saffari, Mojtaba; Raoofian, Reza; Hajjaran, Homa; Hadighi, Ramtin; Khamesipour, Ali; Rezaie, Sassan; Abedkhojasteh, Hoda; Heidari, Mansour

    2013-10-01

    Pentavalent antimonial compounds have been the first line therapy for leishmaniasis; unfortunately the rate of treatment failure of anthroponotic cutaneous leishmaniasis (ACL) is increasing due to emerging of drug resistance. Elucidation of the molecular mechanisms operating in antimony resistance is critical for development of new strategies for treatment. Here, we used a cDNA-AFLP approach to identify gene(s) which are differentially expressed in resistant and sensitive Leishmania tropica field isolates. We identified five genes, aquaglyceroporin (AQP1) acts in drug uptake, ATP-binding cassette (ABC) transporter (MRPA) involved in sequestration of drug, phosphoglycerate kinase (PGK) implicated in glycolysis metabolism, mitogen activated protein kinase (MAPK) and protein tyrosine phosphatase (PTP) responsible for phosphorylation pathway. The results were confirmed using real time RT-PCR which revealed an upregulation of MRPA, PTP and PGK genes and downregulation of AQP1 and MAPK genes in resistant isolate. To our knowledge, this is the first report of identification of PTP and PGK genes potentially implicated in resistance to antimonials. Our findings support the idea that distinct biomolecules might be involved in antimony resistance in L. tropica field isolates.

  20. 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.

  1. 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

  2. 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.

  3. 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.

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

    Directory of Open Access Journals (Sweden)

    Maria Inês Fernandes Pimentel

    2011-04-01

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

  5. Imaging with polycrystalline mercuric iodide detectors using VLSI readout

    Energy Technology Data Exchange (ETDEWEB)

    Turchetta, R.; Dulinski, W.; Husson, D.; Riester, J.L.; Schieber, M.; Zuck, A.; Melekhov, L.; Saado, Y.; Hermon, H.; Nissenbaum, J

    1999-06-01

    Potentially low cost and large area polycrystalline mercuric iodide room-temperature radiation detectors, with thickness of 100-600 {mu}m have been successfully tested with dedicated low-noise, low-power mixed signal VLSI electronics which can be used for compact, imaging solutions. The detectors are fabricated by depositing HgI{sub 2} directly on an insulating substrate having electrodes in the form of microstrips and pixels with an upper continuous electrode. The deposition is made either by direct evaporation or by screen printing HgI{sub 2} mixed with glue such as Poly-Vinyl-Butiral. The properties of these first-generation detectors are quite uniform from one detector to another. Also for each single detector the response is quite uniform and no charge loss in the inter-electrode space have been detected. Because of the low cost and of the polycrystallinity, detectors can be potentially fabricated in any size and shape, using standard ceramic technology equipment, which is an attractive feature where low cost and large area applications are needed. The detectors which act as radiation counters have been tested with a beta source as well as in a high-energy beam of 100 GeV muons at CERN, connected to VLSI, low noise electronics. Charge collection efficiency and uniformity have been studied. The charge is efficiently collected even in the space between strips indicating that fill factors of 100% could be reached in imaging applications with direct detection of radiation. Single photon counting capability is reached with VLSI electronics. These results show the potential of this material for applications demanding position sensitive, radiation resistant, room-temperature operating radiation detectors, where position resolution is essential, as it can be found in some applications in high-energy physics, nuclear medicine and astrophysics.

  6. Effect of Excessive Potassium Iodide on Rat Aorta Endothelial Cells.

    Science.gov (United States)

    Zhang, Man; Zou, Xiaoyan; Lin, Xinying; Bian, Jianchao; Meng, Huicui; Liu, Dan

    2015-08-01

    The aim of the current study was to investigate the effect of excess iodine on rat aorta endothelial cells and the potential underlying mechanisms. Rat aorta endothelial cells were cultured with iodide ion (3506, 4076, 4647, 5218, 5789, 6360, 6931, and 7512 mg/L) for 48 h. Morphological changes of cells were observed with microscope after Wright-Giemsa staining and acridine orange staining. Cell proliferation was determined with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and cell apoptosis was assessed with flow cytometry. The activity of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), endothelial nitric oxide synthase (eNOS), induced nitric oxide synthase (iNOS), and concentrations of malondialdehyde (MDA), glutathione (GSH), and protein carbonyl in culture medium were determined with colorimetric method. The expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) was detected by enzyme linked immunosorbent assay. The results showed that excess iodine induced abnormal morphologic changes of cells, inhibited cell proliferation, and increased apoptosis rate. Iodine also reduced the activity of SOD, GSH-Px, and concentrations of GSH and increased the concentrations of MDA and protein carbonyl in a dose-dependent manner. Moreover, excess iodine decreased the activity of eNOS and increased the activity of iNOS and the expression of ICAM-1 and VCAM-1 in culture medium. Our results suggested that excess iodine exposure increased oxidative stress, caused damage of vascular endothelial cells, and altered the expression of adhesion factors and the activity of NOS. These changes may explain the mechanisms underlying excess iodine-induced vascular injury.

  7. THERAPY OF GRAVES’ DISEASE WITH SODIUM IODIDE-131

    Directory of Open Access Journals (Sweden)

    I Wayan Hartadi Noor

    2013-11-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Graves’ disease is the most common form of thyrotoxicosis, with a peak incidence in the 20-40 year of age group. Females are involved about five times more commonly than male. The easiest sign to recognize patients with Graves’ disease is the present of Graves’ ophthalmopathy. The diagnosis of Graves’ disease may sometimes base only on a physical examination and a medical history. Diffuse thyroid enlargement and sign of thyrotoxicosis, mainly ophthalmopathy and to lesser extent dermopathy, usually adequate for diagnosis. TSH test combined with FT4 test is usually the first laboratory test performs in these patients. The patients suffered Graves’ disease can be treated with antithyroid drug therapy or undergo subtotal Thyroidectomy. Another therapy is by using sodium iodide-131, where this therapy has advantages including easy administration, effectiveness, low expense, and absence of pain. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

  8. Modeling the Detection of Organic and Inorganic Compounds Using Iodide-Based Chemical Ionization.

    Science.gov (United States)

    Iyer, Siddharth; Lopez-Hilfiker, Felipe; Lee, Ben H; Thornton, Joel A; Kurtén, Theo

    2016-02-04

    Iodide-based chemical ionization mass spectrometry (CIMS) has been used to detect and measure concentrations of several atmospherically relevant organic and inorganic compounds. The significant electronegativity of iodide and the strong acidity of hydroiodic acid makes electron transfer and proton abstraction essentially negligible, and the soft nature of the adduct formation ionization technique reduces the chances of sample fragmentation. In addition, iodide has a large negative mass defect, which, when combined with the high resolving power of a high resolution time-of-flight chemical ionization mass spectrometer (HR-ToF-CIMS), provides good selectivity. In this work, we use quantum chemical methods to calculate the binding energies, enthalpies and free energies for clusters of an iodide ion with a number of atmospherically relevant organic and inorganic compounds. Systematic configurational sampling of the free molecules and clusters was carried out at the B3LYP/6-31G* level, followed by subsequent calculations at the PBE/SDD and DLPNO-CCSD(T)/def2-QZVPP//PBE/aug-cc-pVTZ-PP levels. The binding energies, enthalpies, and free energies thus obtained were then compared to the iodide-based University of Washington HR-ToF-CIMS (UW-CIMS) instrument sensitivities for these molecules. We observed a reasonably linear relationship between the cluster binding enthalpies and logarithmic instrument sensitivities already at the PBE/SDD level, which indicates that relatively simple quantum chemical methods can predict the sensitivity of an iodide-based CIMS instrument toward most molecules. However, higher level calculations were needed to treat some outlier molecules, most notably oxalic acid and methylerythritol. Our calculations also corroborated the recent experimental findings that the molecules that the UW-CIMS detects at maximum sensitivity usually have binding enthalpies to iodide which are higher than about 26 kcal/mol, depending slightly on the level of theory.

  9. Iodide Residues in Milk Vary between Iodine-Based Teat Disinfectants.

    Science.gov (United States)

    French, Elizabeth A; Mukai, Motoko; Zurakowski, Michael; Rauch, Bradley; Gioia, Gloria; Hillebrandt, Joseph R; Henderson, Mark; Schukken, Ynte H; Hemling, Thomas C

    2016-07-01

    Majority of iodine found in dairy milk comes from the diet and teat disinfection products used during milking process. The objective of this study was to evaluate the effects of 4 iodine-based teat dips on milk iodide concentrations varying in iodine level (0.25% vs. 0.5%, w/w), normal low viscosity dip versus barrier dip, and application method (dip vs. spray) to ensure safe iodine levels in dairy milk when these products are used. The iodine exposure study was performed during a 2-wk period. The trial farm was purged of all iodine-based disinfection products for 21 d during a prestudy "washout period," which resulted in baseline milk iodide range of 145 to 182 ppb. During the experiment, iodine-based teat dips were used as post-milking teat disinfectants and compared to a non-iodine control disinfectant. Milk iodide residue levels for each treatment was evaluated from composited group samples. Introduction of different iodine-based teat disinfectants increased iodide residue content in milk relative to the control by between 8 and 29 μg/L when averaged across the full trial period. However, residues levels for any treatment remained well below the consumable limit of 500 μg/L. The 0.5% iodine disinfectant increased milk iodide levels by 20 μg/L more compared to the 0.25% iodine. Compared to dip-cup application, spray application significantly increased milk iodide residue by 21 μg/L and utilized approximately 23% more teat dip. This carefully controlled study demonstrated an increase in milk iodide concentrations from iodine disinfectants, but increases were small and within acceptable limits.

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

    Science.gov (United States)

    Sahin, Cuneyt

    The emerging field of spintronics relies on the manipulation of electron spin in order to use it in spin-based electronics. Such a paradigm change has to tackle several challenges including finding materials with sufficiently long spin lifetimes and materials which are efficient in generating pure spin currents. This thesis predicts that two types of material families could be a solution to the aforementioned challenges: complex oxides and bismuth based materials. We derived a general approach for constructing an effective spin-orbit Hamiltonian which is applicable to all nonmagnetic materials. This formalism is useful for calculating spin-dependent properties near an arbitrary point in momentum space. We also verified this formalism through comparisons with other approaches for III-V semiconductors, and its general applicability is illustrated by deriving the spin-orbit interaction and predicting spin lifetimes for strained strontium titanate (STO) and a two-dimensional electron gas in STO (such as at the LAO/STO interface). Our results suggest robust spin coherence and spin transport properties in STO related materials even at room temperature. In the second part of the study we calculated intrinsic spin Hall conductivities for bismuth-antimony (BISb) semimetals with strong spin-orbit couplings, from the Kubo formula and using Berry curvatures evaluated throughout the Brillouin zone from a tight-binding Hamiltonian. Nearly crossing bands with strong spin-orbit interaction generate giant spin Hall conductivities in these materials, ranging from 474 ((h/e)O--1cm--1) for bismuth to 96((h/e)O--1cm --1) for antimony; the value for bismuth is more than twice that of platinum. The large spin Hall conductivities persist for alloy compositions corresponding to a three-dimensional topological insulator state, such as Bi0.83Sb0.17. The spin Hall conductivity could be changed by a factor of 5 for doped Bi, or for Bi0.83Sb0.17, by changing the chemical potential by 0.5 e

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

    Science.gov (United States)

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

    2014-10-16

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

  12. A New Process of Diaphragm Electrowinning for Recovery of Antimony From Antimony-Gold Concentrate%锑金精矿隔膜电积预处理新工艺研究

    Institute of Scientific and Technical Information of China (English)

    刘宗强; 彭思尧; 杨建英; 张绪亮; 李焌源; 雷杰; 杨建广

    2015-01-01

    针对现行锑金精矿冶炼工艺存在能耗高、污染重、效率低等问题,研究了用锑隔膜电积技术处理复杂锑金精矿,考察了锑隔膜电积技术对多类复杂锑金精矿处理的适应性和经济技术指标。结果表明:锑隔膜电积技术适用于处理多类锑金精矿;经该工艺处理后的锑金精矿中锑浸出率达99%以上,97%以上的金富集在浸出渣中;浸出液中的锑通过净化—电积处理后可得到99.5%以上的电积锑,而原料中以氧化砷形式存在的砷基本被浸入到溶液中,其他形式的砷则留在浸出渣中;浸出液中的砷通过次亚磷酸钠还原可以深度脱除到3 mg/L 以下,实现砷与锑的高效分离,最终电积锑中的砷可以降到痕量。%In view of the problems of high energy consumption ,heavy pollution ,low efficiency in the current gold‐antimony concentrate smelting process ,a diaphragm electrowinning process was applied to process the complex antimony‐gold concentrate .Experiment results show that the diaphragm electrowinning process is well suitable for treating the antimony ‐gold concentrates .The leaching efficiency of antimony can reach 99% ,and more than 97% of the gold is enriched in the leached residue .Antimony in the leached solution can be extracted through purification‐electrowinning process in the form of 99 .5% electrowinning antimony plate .All arsenic trioxide embracing in the antimony‐gold concentrates can be leached into solution ,while other forms of arsenic can remain in the leached residue .By sodium hypophosphite reduction ,the leached arsenic can be deeply precipitated from the leached solution to the extent of below 3 mg/L ,and the arsenic content in the subsequent electrowinning antimony can be reduced to trace .

  13. 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.

  14. 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.

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

    Science.gov (United States)

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

    2016-09-01

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

  16. 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.

  17. Spectroscopic properties of Eu-doped antimony-germanate glass and glass-ceramics

    Science.gov (United States)

    Zmojda, J.; Kochanowicz, M.; Miluski, P.; Ragin, T.; Dorosz, D.; ZajÄ c, A.

    2016-09-01

    In our work we focused on possibility of obtaining phosphate nano-phase structures in antimony-germanate glasses doped with europium ions. The glasses with molar composition of 50(Sb2O3 - GeO2) - 50(SiO2 - Al2O3 - Na2O) doped with 0.5mol% Eu2O3 were prepared by standard melt-quenching method. In order to optimize glass-ceramic system the influence of phosphate concentration (up to 10mol%) on spectroscopic properties have been investigated. The symmetry nature of molecular structure around europium ions have been determined from the intensity ratio between (5D0 →7F2)/(5D0 →7F1) transitions. The effect of prominent Stark splitting of luminescence band at 612 nm characterised as "hypersensitive transition" into 3 sub-wavelength was observed in glasses with 1mol% and 3mol% of P2O5.

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

    Science.gov (United States)

    Ali, N.; Hussain, A.; Ahmed, R.; Wan Shamsuri, W. N.; Fu, Y. Q.

    2016-12-01

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

  19. Effects of Antimony Doping in Polycrystalline CdTe Thin-Film Solar Cells

    Science.gov (United States)

    Okamoto, Tamotsu; Ikeda, Shigeyuki; Nagatsuka, Satsuki; Hayashi, Ryoji; Yoshino, Kaoru; Kanda, Yohei; Noda, Akira; Hirano, Ryuichi

    2012-10-01

    The effects of antimony (Sb) doping of the CdTe layer in the CdTe solar cells were investigated using Sb-doped CdTe powders as source materials for CdTe deposition by the close-spaced sublimation (CSS) method. Conversion efficiency increased with increasing Sb concentration below 1×1018 cm-3, mainly owing to the improvement of the fill factor. Secondary ion microprobe mass spectrometry (SIMS) depth profile revealed that the Sb impurities at a concentration of approximately 1×1016 cm-3 were incorporated into the CdTe layer when using the Sb-doped CdTe source of 1×1018 cm-3. The observation of surface morphology showed that the grain sizes were improved by Sb addition. Therefore, the improved performance upon Sb addition to CdTe solar cells was probably due to the improvements in crystallinity, such as increased grain size.

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

    Institute of Scientific and Technical Information of China (English)

    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

  1. 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.

  2. Potentiometric stripping analysis (PSA) for monitoring of antimony in samples of vegetation from a mining area.

    Science.gov (United States)

    Toro Gordillo, M C; Pinilla Gil, E; Rodríguez González, M A; Murciego Murciego, A; Ostapczuk, P

    2001-06-01

    A potentiometric stripping analysis (PSA) method has been developed and checked for the fast and reliable determination of antimony in vegetation samples of Cistus ladanifer from a mining area in Badajoz, Southwest Spain. The method, modified from previous PSA methods for Sb in environmental samples, is based on dry ashing of the homogenized leaves, dissolution in hydrochloric acid, and PSA analysis on a mercury film plated on to a glassy carbon disk electrode. The influence of experimental variables such as the deposition potential, the deposition time, the signal stability and the calibration parameters, has been investigated. The method has been compared with an independent technique (instrumental neutron activation analysis) by analysis of standards and reference materials and comparison of the results. As a result of automation of the PSA equipment, the proposed method enables unattended analysis of 20 digested samples in a total time of 2 h, thus providing a useful tool for Sb monitoring of a large number of samples.

  3. Antimony uptake by Zea mays (L.) and Helianthus annuus (L.) from nutrient solution.

    Science.gov (United States)

    Tschan, Martin; Robinson, Brett; Schulin, Rainer

    2008-04-01

    We investigated the extent of Sb uptake by maize (Zea mays) and sunflower (Helianthus annuus) from nutrient solutions containing concentrations from 3 to 24 mg/L of potassium antimonate, with the aim of determining the potential of Sb to enter the food chain. The maximum shoot Sb concentrations in Z. mays and H. annuus were 41 mg/kg and 77 mg/kg dry weight, respectively. There was no significant difference in Sb uptake between species. The average bioaccumulation coefficients (the plant/solution concentration quotients) were 1.02 and 1.93 for Z. mays and H. annuus, respectively. Phosphate addition did not affect plant growth or Sb uptake. Antimony uptake by both Z. mays and H. annuus is unlikely to pose a health risk to animals and humans.

  4. [Determination of iodide, thiocyanate and perchlorate ions in environmental water by two-dimensional ion chromatography].

    Science.gov (United States)

    Lin, Li; Wang, Haibo; Shi, Yali

    2013-03-01

    A procedure for the determination of iodide, thiocyanate and perchlorate ions in environmental water by two-dimensional ion chromatography has been developed. At first the iodide, thiocyanate and perchlorate ions were separated from interfering ions by a column (IonPac AS16, 250 mm x 4 mm). The iodide ion, thiocyanate and perchlorate ions were then enriched with an enrichment column (MAC-200, 80 mm x 0.75 mm). In the 2nd-dimensional chromatography, iodide thiocyanate and perchlorate ions were separated and quantified by a capillary column (IonPac AS20 Capillary, 250 mm x 0.4 mm). The linear ranges were 0.05 -100 pg/L with correlation coefficients of 0. 999 9, and the detection limits were 0. 02 - 0.05 micro gg/L. The spiked recoveries of iodide, thiocyanate and perchlorate ions were in the range of 85.1% to 100.1%. The relative standard deviations of the recoveries were 1.7% to 4.9%.

  5. Trapping radiodine, in the form of methyl iodide, on nuclear carbon

    Energy Technology Data Exchange (ETDEWEB)

    Nacapricha, D. [Mahidol Univ., Bangkok (Thailand); Taylor, C. [John Moores Univ., Liverpool (United Kingdom)

    1996-12-31

    Studies have been performed on potassium-iodide-impregnated charcoals of the type used in the nuclear industry for trapping radioiodine released during nuclear fission. The effects of various parameters on the trapping efficiency of methyl iodide have been investigated. A variation in particle size within a bulk charcoal caused poor precision in K value measurements because of differences in surface area, pore volume, and bed density, leading to differences in the deposition of the impregnant. Precision is improved by sieving the charcoal to a narrower size because smaller particles have a higher porosity. This finding is supported by surface area and pore measurements. Two methods of impregnation are compared by measuring K values and the deposition of potassium iodide. Charcoal impregnated by rotary evaporation exhibits both higher K values and higher potassium iodide contents than sprayed charcoal. Two designs of spraying drum are compared: a drum with helical vanes allows more efficient deposition and more uniform distribution of impregnant than a drum with axial vanes. A decrease in the K value with increasing humidity correlates with the available surface area. A similar correlation exists between water content and available pore volume. Aging of potassium-iodide-impregnated charcoal, caused by the formation of oxygen complexes on the surface, is associated with significant falls in K value. K values of charcoals also can be restored to at least their original values by heat treatment in the absence of air. 12 refs., 6 figs., 1 tab.

  6. Estradiol decreases iodide uptake by rat thyroid follicular FRTL-5 cells

    Directory of Open Access Journals (Sweden)

    Furlanetto T.W.

    2001-01-01

    Full Text Available Estradiol has well-known indirect effects on the thyroid. A direct effect of estradiol on thyroid follicular cells, increasing cell growth and reducing the expression of the sodium-iodide symporter gene, has been recently reported. The aim of the present investigation was to study the effect of estradiol on iodide uptake by thyroid follicular cells, using FRTL-5 cells as a model. Estradiol decreased basal iodide uptake by FRTL-5 cells from control levels of 2.490 ± 0.370 to 2.085 ± 0.364 pmol I-/µg DNA at 1 ng/ml (P<0.02, to 1.970 ± 0.302 pmol I-/µg DNA at 10 ng/ml (P<0.003, and to 2.038 ± 0.389 pmol I-/µg DNA at 100 ng/ml (P<0.02. In addition, 4 ng/ml estradiol decreased iodide uptake induced by 0.02 mIU/ml thyrotropin from 8.678 ± 0.408 to 7.312 ± 0.506 pmol I-/µg DNA (P<0.02. A decrease in iodide uptake by thyroid cells caused by estradiol has not been described previously and may have a role in goiter pathogenesis.

  7. Processes of adsorption/desorption of iodides and cadmium cations onto/from Ag(111

    Directory of Open Access Journals (Sweden)

    VLADIMIR D. JOVIĆ

    2011-02-01

    Full Text Available In this work, the adsorption/desorption processes of iodides and cadmium cations in the presence of iodides onto/from Ag(111 were investigated. It was shown that both processes were complex, characterized by several peaks on the cyclic voltammograms (CVs. By PeakFit analysis of the recorded CVs and subsequent fitting of the obtained peaks by the Frumkin adsorption isotherm, the interaction parameter (f and the Gibbs energy of adsorption (DGads for each adsorbed phase were determined. In the case of iodide adsorption, four peaks were characterized by negative values of f, indicating attractive lateral interaction between the adsorbed anions, while two of them possessed value of f < –4, indicating phase transition processes. The adsorption/desorption processes of cadmium cations (underpotential deposition – UPD of cadmium in the presence of iodide anions was characterized by two main peaks, each of them being composed of two or three peaks with negative values of f. By the analysis of charge vs. potential dependences obtained either from the CVs or current transients on potentiostatic pulses, it was concluded that adsorbed iodides did not undergo desorption during the process of Cd UPD, but became replaced by Cd ad-atoms and remained adsorbed on top of a Cd layer and/or in between Cd the ad-atoms.

  8. Proton and iodine-127 nuclear magnetic resonance studies on the binding of iodide by lactoperoxidase

    Energy Technology Data Exchange (ETDEWEB)

    Sakurada, J.; Takahashi, S.; Shimizu, T.; Hatano, M.; Nakamura, S.; Hosoya, T.

    1987-10-06

    Interaction of an iodide ion with lactoperoxidase was studied by the use of /sup 1/H NMR, /sup 127/I NMR, and optical difference spectrum techniques. /sup 1/H NMR spectra demonstrated that a major broad hyperfine-shifted signal at about 60 ppm, which is ascribed to the heme peripheral methyl protons, was shifted toward high field by adding KI, indicating the binding of iodide to the active site of the enzyme; the dissociation constant was estimated to be 38 mM at pH 6.1. The binding was further detected by /sup 127/I NMR, showing no competition with cyanide. Both /sup 1/H NMR and /sup 127/I NMR revealed that the binding of iodide to the enzyme is facilitated by the protonation of an ionizable group with a pK/sup a/ value of 6.0-6.8, which is presumably the distal histidyl residue. Optical difference spectra showed that the binding of an aromatic donor molecule to the enzyme is slightly but distinctly affected by adding KI. On the basis of these results, it was suggested that an iodide ion binds to lactoperoxidase outside the heme crevice but at the position close enough to interact with the distal histidyl residue which possibly mediates electron transport in the iodide oxidation reaction.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. Quantification of propidium iodide delivery with millisecond electric pulses: A model study

    CERN Document Server

    Yu, Miao

    2014-01-01

    A model study of propidium iodide delivery with millisecond electric pulses is presented; this work is a companion of the experimental efforts by Sadik et al. [1]. Both membrane permeabilization and delivery are examined with respect to six extra-cellular conductivities. The transmembrane potential of the permeabilized regions exhibits a consistent value, which corresponds to a bifurcation point in the pore-radius-potential relation. Both the pore area density and membrane conductance increase with an increasing extra-cellular conductivity. On the other hand, the inverse correlation between propidium iodide delivery and extra-cellular conductivity as observed in the experiments is quantitatively captured by the model. This agreement confirms that this behavior is primarily mediated by electrophoretic transport during the pulse. The results suggest that electrophoresis is important even for the delivery of small molecules such as propidium iodide. The direct comparison between model prediction and experimental...

  15. Salty glycerol versus salty water surface organization: bromide and iodide surface propensities.

    Science.gov (United States)

    Huang, Zishuai; Hua, Wei; Verreault, Dominique; Allen, Heather C

    2013-07-25

    Salty NaBr and NaI glycerol solution interfaces are examined in the OH stretching region using broadband vibrational sum frequency generation (VSFG) spectroscopy. Raman and infrared (IR) spectroscopy are used to further understand the VSFG spectroscopic signature. The VSFG spectra of salty glycerol solutions reveal that bromide and iodide anions perturb the interfacial glycerol organization in a manner similar as that found in aqueous halide salt solutions, thus confirming the presence of bromide and iodide anions at the glycerol surface. Surface tension measurements are consistent with the surface propensity suggested by the VSFG data and also show that the surface excess increases with increasing salt concentration, similar to that of water. In addition, iodide is shown to have more surface prevalence than bromide, as has also been determined from aqueous solutions. These results suggest that glycerol behaves similarly to water with respect to surface activity and solvation of halide anions at its air/liquid interface.

  16. Preparation, Characterization and Optical Properties of Host-guest Nanocomposite Material Mordenite-silver Iodide

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Silver iodide nanoclusters were successfully prepared in the channels of mordenite by a heat diffusion method. Powder X-ray diffraction, adsorption technique and infrared spectroscopy were used to characterize the prepared materials, which showed that the guest silver iodide had been encapsulated in the channels of mordenite. The optical properties of the solid phase diffuse reflectance absorption of nanocomposite material NaM-AgI were studied, showing that the absorption bands of the diffuse reflectance absorption of the prepared material moved to the region of high energy. The absorption peak of the material prepared shifted to the region of high energy. Namely, blue shift was caused. This has demonstrated the incorporation of silver iodide into the channels of the zeolite. We observed the luminescence and surface photovoltage spectra of NaM-AgI sample, proposing the mechanisms of the photoluminescence and photovoltaic responses.

  17. New Microporous Polymer Electrolyte Based on Polysiloxane Grafted with Imidazolium Iodide Moieties for DSSC

    Directory of Open Access Journals (Sweden)

    Yan Yang

    2011-01-01

    Full Text Available Two types of polysiloxane grafted with different ratio of imidazolium iodide moieties (IL-SiO2 have been synthesized to develop a micro-porous polymer electrolyte for quasi-solid-state dye-sensitized solar cells. The samples were characterized by 1HNMR, FT-IR spectrum, XRD, TEM and SEM, respectively. Moreover, the ionic conductivity of the electrolytes was measured by electrochemical workstation. Nanostructured polysiloxane containing imidazolium iodide showed excellent compatibility with organic solvent and polymer matrix for its ionic liquid characteristics. Increasing the proportion of imidazolium iodide moieties in polysiloxane improved the electrochemical behavior of the gel polymer electrolyte. A dye-sensitized solar cell with gel polymer electrolyte yielded an open-circuit voltage of 0.70 V, short-circuit current of 11.19 mA cm−2, and the conversion efficiency of 3.61% at 1 sun illumination.

  18. Optimization of mercuric iodide platelets growth by the polymer controlled vapor transport method

    Directory of Open Access Journals (Sweden)

    Fornaro L.

    1999-01-01

    Full Text Available Mercuric iodide crystals in their platelet habit were grown by the polymer controlled vapor transport method. Mercuric iodide 99% in purity was sublimated at temperatures about 122 - 126 °C and vacuum conditions (10-5 mmHg, after selecting an appropriate polymer. Temperature profiles and experimental heat transfer models were determined for two growth furnaces using different insulator configurations for the cold extreme (air, ceramic wool, grilon, copper and ceramic wool. Growth conditions for few and separate nucleation points and large crystals were determined. Representative samples were characterized by optical microscopy and by measuring the current density and apparent resistivity of the material. Future optimization and comparisons with others mercuric iodide crystal growth methods are included.

  19. Effect of Cytokine on the Expression of Sodium Iodide Symporter Gene in Breast Cancer Cell

    Institute of Scientific and Technical Information of China (English)

    JIAYue; LIUChao; TANGWei; LIUCui-ping; QINYou-wen; YUANQing-xing; LIQian; MAOXiao-dong; DIFu-song

    2004-01-01

    To investigate the effect of cytokines (TNF-α, IFN-γ and IL-6) on the expression of sodi-um-iodide symporter(NIS) gene in breast cancer cell (MCF-7). Methods:The breast cancer cell was cultureds with negative control culture or cultures with different concentrations of cytokines for 72 h. NIS germ mRNA in breast cancer cells cultured was determined by reverse transcriptase-polymerase chain reaction(RT-PCR). Results:Expression of sodium-iodide symporter mRNA can be found decreasing along with increasing the concentration of cytokine dose-depen-dently. Conchzs/on ~ Cytokine may play a role in iodide-uptake modulating in breast cancer cells by their effect on NIS germ expression.

  20. All-Solid-State Iodide Selective Electrode for Iodimetry of Iodized Salts and Vitamin C

    Directory of Open Access Journals (Sweden)

    TIRUWORK MEQUANINT

    2012-12-01

    Full Text Available A laboratory-made all-solid state iodide selective electrode, with Ag2S-AgI coated on a graphite rod recovered from dry cell battery, was prepared according to previous procedures. The electrode’s linear response to iodide was in the concentration range of 10-6 M to 10-1 M with a slope of 56.85 mV/decade and a detection limit of 6×10-7M. Iodate recovery test for laboratory formulated iodate-iodized salt was found to be 98.6 % with a standard deviation of 1.14%. The titratability of the iodized salt solution was at least 10-200 ppm potassium iodate (6-120 ppm iodine, exhibiting distinct endpoints in the range wider than the ones set in regulatory standards and reflecting that QC monitoring in production and stability decline of iodine content upon storage can be performed with the electrode method. On the basis this potentiometric titration, the application of the laboratory-made iodide electrode (vs. a saturated calomel reference electrode was extended to the determination of iodine in commercial iodized salts. In all the iodine assays, the iodate-iodized salt was initially treated with acid and an excess of iodide before titration against Na2S2O3 solution. The iodine content in table salts iodized with iodide was determined by direct potentiometry. The electrode was further used for vitamin C (ascorbic acid determinations in pharmaceutical tablets and orange juice by back titrating excess I3- against standard Na2S2O3 in acidic media. The overall outcome is that the iodide ISE can be used as sharp endpoint indicator for these titrimetric reactions in place of the well known official, but visually monitored, starch- triodide end-point reaction detection.

  1. Iodide uptake in human anaplastic thyroid carcinoma cells after transfer of the human thyroid peroxidase gene

    Energy Technology Data Exchange (ETDEWEB)

    Haberkom, U. [Clinical Cooperation Unit Nuclear Medicine, German Cancer Research Center, Heidelberg (Germany); Dept. of Nuclear Medicine, Univ. of Heidelberg (Germany); Altmann, A.; Jiang, S.; Morr, I.; Mahmut, M. [Clinical Cooperation Unit Nuclear Medicine, German Cancer Research Center, Heidelberg (Germany); Eisenhut, M. [Dept. of Nuclear Medicine, Univ. of Heidelberg (Germany)

    2001-05-01

    Human thyroperoxidase (hTPO) is critical for the accumulation of iodide in thyroid tissues. Poorly differentiated and anaplastic thyroid tumours which lack thyroid-specific gene expression fail to accumulate iodide and, therefore, do not respond to iodine-131 therapy. We consequently investigated whether transfer of the hTPO gene is sufficient to restore the iodide-trapping capacity in undifferentiated thyroid and non-thyroid tumour cells. The human anaplastic thyroid carcinoma cell lines C643 and SW1736, the rat Morris hepatoma cell line MH3924A and the rat papillary thyroid carcinoma cell line L2 were used as in vitro model systems. Employing a bicistronic retroviral vector based on the myeloproliferative sarcoma virus for the transfer of the hTPO and the neomycin resistance gene, the C643 cells and SW1736 cells were transfected while the L2 cells and MH3924A cells were infected with retroviral particles. Seven recombinant C643 and seven SW1736 cell lines as well as four recombinant L2 and four MH3924A cell lines were established by neomycin selection. They were studied for hTPO expression using an antibody-based luminescence kit, followed by determination of the enzyme activity in the guaiacol assay and of the iodide uptake capacity in the presence of Na{sup 125}I. Genetically modified cell lines expressed up to 1,800 times more hTPO as compared to wild type tumour cells. The level of hTPO expression varied significantly between individual neomycin-resistant cell lines, suggesting that the recombinant retroviral DNA was integrated at different sites of the cellular genome. The accumulation of iodide, however, was not significantly enhanced in individual recombinant cell lines, irrespective of low or high hTPO expression. Moreover, there was no correlation between hTPO expression and enzyme activity in individual cell lines. The transduction of the hTPO gene per se is not sufficient to restore iodide trapping in non-iodide-concentrating tumour cells. Future

  2. Development of W/O Microemulsion for Transdermal Delivery of Iodide Ions

    OpenAIRE

    Lou, Hao; Qiu, Ni; Crill, Catherine; Helms, Richard; Almoazen, Hassan

    2012-01-01

    The objective of this study was to develop a water-in-oil (w/o) microemulsion which can be utilized as a transdermal delivery for iodide ions. Several w/o microemulsion formulations were prepared utilizing Span 20, ethanol, Capryol 90®, and water. The selected formulations had 5%, 10%, 15%, 20%, and a maximum of 23% w/w water content. Potassium iodide (KI) was incorporated in all formulations at 5% w/v. Physicochemical characterizations were conducted to evaluate the structure and stability. ...

  3. All-Solid-State Iodide Selective Electrode for Iodimetry of Iodized Salts and Vitamin C

    OpenAIRE

    TIRUWORK MEQUANINT; GHIRMA MOGES; MERID TESSMA; SOLOMON MEHRETU

    2012-01-01

    A laboratory-made all-solid state iodide selective electrode, with Ag2S-AgI coated on a graphite rod recovered from dry cell battery, was prepared according to previous procedures. The electrode’s linear response to iodide was in the concentration range of 10-6 M to 10-1 M with a slope of 56.85 mV/decade and a detection limit of 6×10-7M. Iodate recovery test for laboratory formulated iodate-iodized salt was found to be 98.6 % with a standard deviation of 1.14%. The titratability of the iodize...

  4. Tris(1,2-dimethoxyethane-κ2O,O′iodidocalcium iodide

    Directory of Open Access Journals (Sweden)

    Siou-Wei Ou

    2012-02-01

    Full Text Available In the title complex, [CaI(C4H10O23]I, the CaII atom is seven-coordinated by six O atoms from three 1,2-dimethoxyethane (DME ligands and one iodide anion in a distorted pentagonal–bipyramidal geometry. The I atom and one of the O atoms from a DME ligand lie in the axial positions while the other O atoms lie in the basal plane. The other iodide anion is outside the complex cation.

  5. Glycosylation of Sodium/Iodide Symporter (NIS) Regulates Its Membrane Translocation and Radioiodine Uptake

    OpenAIRE

    Taemoon Chung; Hyewon Youn; Chan Joo Yeom; Keon Wook Kang; June-Key Chung

    2015-01-01

    Purpose Human sodium/iodide symporter (hNIS) protein is a membrane glycoprotein that transports iodide ions into thyroid cells. The function of this membrane protein is closely regulated by post-translational glycosylation. In this study, we measured glycosylation-mediated changes in subcellular location of hNIS and its function of iodine uptake. Methods HeLa cells were stably transfected with hNIS/tdTomato fusion gene in order to monitor the expression of hNIS. Cellular localization of hNIS ...

  6. Studying Equilibrium in the Chemical Reaction between Ferric and Iodide Ions in Solution Using a Simple and Inexpensive Approach

    Science.gov (United States)

    Nikolaychuk, Pavel Anatolyevich; Kuvaeva, Alyona Olegovna

    2016-01-01

    A laboratory experiment on the study of the chemical equilibrium based on the reaction between ferric and iodide ions in solution with the formation of ferrous ions, free iodine, and triiodide ions is developed. The total concentration of iodide and triiodide ions in the reaction mixture during the reaction is determined by the argentometric…

  7. Efficiency enhancement in dye sensitized solar cells using gel polymer electrolytes based on a tetrahexylammonium iodide and MgI2 binary iodide system.

    Science.gov (United States)

    Bandara, T M W J; Dissanayake, M A K L; Jayasundara, W J M J S R; Albinsson, I; Mellander, B-E

    2012-06-28

    Quasi-solid-state dye-sensitized solar cells have drawn the attention of scientists and technologists as a potential candidate to supplement future energy needs. The conduction of iodide ions in quasi-solid-state polymer electrolytes and the performance of dye sensitized solar cells containing such electrolytes can be enhanced by incorporating iodides having appropriate cations. Gel-type electrolytes, based on PAN host polymers and mixture of salts tetrahexylammonium iodide (Hex4N(+)I(-)) and MgI2, were prepared by incorporating ethylene carbonate and propylene carbonate as plasticizers. The salt composition in the binary mixture was varied in order to optimize the performance of solar cells. The electrolyte containing 120% Hex4N(+)I(-) with respect to weight of PAN and without MgI2 showed the highest conductivity out of the compositions studied, 2.5 × 10(-3) S cm(-1) at 25 °C, and a glass transition at -102.4 °C. However, the electrolyte containing 100% Hex4N(+)I(-) and 20% MgI2 showed the best solar cell performance highlighting the influence of the cation on the performance of the cell. The predominantly ionic behaviour of the electrolytes was established from the dc polarization data and all the electrolytes exhibit iodide ion transport. Seven different solar cells were fabricated employing different electrolyte compositions. The best cell using the electrolyte with 100% Hex4N(+)I(-) and 20% MgI2 with respect to PAN weight showed 3.5% energy conversion efficiency and 8.6 mA cm(-2) short circuit current density.

  8. 锑合金化在镁合金中的应用%Application of Antimony Alloying in Magnesium Alloy

    Institute of Scientific and Technical Information of China (English)

    丛孟启; 刘劲松; 李子全; 闫明阳; 孙颖迪; 黄敏; 陈可; 刘亚妮

    2012-01-01

    The latest research progress in magnesium alloys containing antimony in recent years is discussed Effects of antimony additions on the cast-ability, microstructure, tensile properties, creep behavior, damping properties and corrosion resistance of Mg-Al and Mg-Zn based alloys are summarized. Finally, some further research orientations of magnesium alloys containing Sb in the present study are suggested.%综述了近年来含锑镁合金的研究进展,总结了锑元素对Mg-Al和Mg-Zn系镁合金铸造性能、金相组织、力学性能、蠕变性能、阻尼性能、耐蚀性能6方面的影响.最后,展望了含锑镁合金的研究方向.

  9. The effect of verapamil on in vitro susceptibility of promastigote and amastigote stages of Leishmania tropica to meglumine antimoniate.

    Science.gov (United States)

    Shokri, Azar; Sharifi, Iraj; Khamesipour, Ali; Nakhaee, Nozar; Fasihi Harandi, Majid; Nosratabadi, Jafar; Hakimi Parizi, Maryam; Barati, Mohammad

    2012-03-01

    Pentavalent antimonials are the standard treatment for cutaneous leishmaniasis (CL) with low efficacy and resistance is emerging. CL is increased significantly in respect to incidence rate and expanding to new foci. In the present study, the effect of verapamil on in vitro susceptibility of promastigote and amastigote stages of Leishmania tropica to meglumine antimoniate (MA, Glucantime) was evaluated using colorimetric assay (MTT) and in a macrophage model, respectively. Verapamil, as a calcium channel blocker, affects drug uptake by preventing of drug efflux from the cells. In promastigote form, several concentrations of MA with or without verapamil showed significant decrease (P tropica to MA. Further works are required to evaluate this synergistic effect on animal model or volunteer human subjects.

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

    Science.gov (United States)

    Domínguez-Renedo, Olga; Gómez González, M Jesús; Arcos-Martínez, M Julia

    2009-01-01

    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.

  11. Miltefosine and Antimonial Drug Susceptibility of Leishmania Viannia Species and Populations in Regions of High Transmission in Colombia

    Science.gov (United States)

    Fernández, Olga Lucía; Diaz-Toro, Yira; Muvdi, Sandra; Rodríguez, Isabel; Gomez, María Adelaida; Saravia, Nancy Gore

    2014-01-01

    Background Pentavalent antimonials have been the first line treatment for dermal leishmaniasis in Colombia for over 30 years. Miltefosine is administered as second line treatment since 2005. The susceptibility of circulating populations of Leishmania to these drugs is unknown despite clinical evidence supporting the emergence of resistance. Methodology/Principal Findings In vitro susceptibility was determined for intracellular amastigotes of 245 clinical strains of the most prevalent Leishmania Viannia species in Colombia to miltefosine (HePC) and/or meglumine antimoniate (SbV); 163, (80%) were evaluated for both drugs. Additionally, susceptibility to SbV was examined in two cohorts of 85 L. V. panamensis strains isolated between 1980–1989 and 2000–2009 in the municipality of Tumaco. Susceptibility to each drug differed among strains of the same species and between species. Whereas 68% of L. V. braziliensis strains presented in vitro resistance to HePC, 69% were sensitive to SbV. Resistance to HePC and SbV occurred respectively, in 20% y 21% of L. panamensis strains. Only 3% of L. V. guyanensis were resistant to HePC, and none to SbV. Drug susceptibility differed between geographic regions and time periods. Subpopulations having disparate susceptibility to SbV were discerned among L. V. panamensis strains isolated during 1980–1990 in Tumaco where resistant strains belonged to zymodeme 2.3, and sensitive strains to zymodeme 2.2. Conclusions/Significance Large scale evaluation of clinical strains of Leishmania Viannia species demonstrated species, population, geographic, and epidemiologic differences in susceptibility to meglumine antimoniate and miltefosine, and provided baseline information for monitoring susceptibility to these drugs. Sensitive and resistant clinical strains within each species, and zymodeme as a proxy marker of antimony susceptibility for L. V. panamensis, will be useful in deciphering factors involved in susceptibility and the distribution

  12. Potentiometric stripping analysis of antimony based on carbon paste electrode modified with hexathia crown ether and rice husk

    Energy Technology Data Exchange (ETDEWEB)

    Gadhari, Nayan S.; Sanghavi, Bankim J. [Department of Chemistry, University of Mumbai, Vidyanagari, Santacruz (East), Mumbai 400098 (India); Srivastava, Ashwini K., E-mail: aksrivastava@chem.mu.ac.in [Department of Chemistry, University of Mumbai, Vidyanagari, Santacruz (East), Mumbai 400098 (India)

    2011-10-03

    Highlights: {yields} Potentiometric stripping analysis (PSA) employed for the determination of antimony. {yields} Hexathia-18C6 and rice husk modified carbon paste electrode developed for the analysis. {yields} Lowest detection limit obtained for the determination of Sb(III) using PSA. {yields} Analysis of Sb in pharmaceutical formulations, human hair, blood serum, urine and sea water. {yields} Rice husk used as a modifier for the first time in electrochemistry. - Abstract: An electrochemical method based on potentiometric stripping analysis (PSA) employing a hexathia 18C6 (HT18C6) and rice husk (RH) modified carbon paste electrode (HT18C6-RH-CPE) has been proposed for the subnanomolar determination of antimony. The characterization of the electrode surface has been carried out by means of scanning electron microscopy, cyclic voltammetry, electrochemical impedance spectroscopy and chronocoulometry. By employing HT18C6-RH-CPE, a 12-fold enhancement in the PSA signal (dt/dE) was observed as compared to plain carbon paste electrode (PCPE). Under the optimized conditions, dt/dE (s V{sup -1}) was proportional to the Sb(III) concentration in the range of 1.42 x 10{sup -8} to 6.89 x 10{sup -11} M (r = 0.9944) with the detection limit (S/N = 3) of 2.11 x 10{sup -11} M. The practical analytical utilities of the modified electrode were demonstrated by the determination of antimony in pharmaceutical formulations, human hair, sea water, urine and blood serum samples. The prepared modified electrode showed several advantages, such as simple preparation method, high sensitivity, very low detection limit and excellent reproducibility. Moreover, the results obtained for antimony analysis in commercial and real samples using HT18C6-RH-CPE and those obtained by inductively coupled plasma-atomic emission spectrometry (ICP-AES) are in agreement at the 95% confidence level.

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

    OpenAIRE

    Olga Domínguez-Renedo; M. Julia Arcos-Martínez; M. Jesús Gómez González

    2009-01-01

    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 ...

  14. Miltefosine and antimonial drug susceptibility of Leishmania Viannia species and populations in regions of high transmission in Colombia.

    Directory of Open Access Journals (Sweden)

    Olga Lucía Fernández

    2014-05-01

    Full Text Available Pentavalent antimonials have been the first line treatment for dermal leishmaniasis in Colombia for over 30 years. Miltefosine is administered as second line treatment since 2005. The susceptibility of circulating populations of Leishmania to these drugs is unknown despite clinical evidence supporting the emergence of resistance.In vitro susceptibility was determined for intracellular amastigotes of 245 clinical strains of the most prevalent Leishmania Viannia species in Colombia to miltefosine (HePC and/or meglumine antimoniate (Sb(V; 163, (80% were evaluated for both drugs. Additionally, susceptibility to Sb(V was examined in two cohorts of 85 L. V. panamensis strains isolated between 1980-1989 and 2000-2009 in the municipality of Tumaco. Susceptibility to each drug differed among strains of the same species and between species. Whereas 68% of L. V. braziliensis strains presented in vitro resistance to HePC, 69% were sensitive to Sb(V. Resistance to HePC and Sb(V occurred respectively, in 20% y 21% of L. panamensis strains. Only 3% of L. V. guyanensis were resistant to HePC, and none to Sb(V. Drug susceptibility differed between geographic regions and time periods. Subpopulations having disparate susceptibility to Sb(V were discerned among L. V. panamensis strains isolated during 1980-1990 in Tumaco where resistant strains belonged to zymodeme 2.3, and sensitive strains to zymodeme 2.2.Large scale evaluation of clinical strains of Leishmania Viannia species demonstrated species, population, geographic, and epidemiologic differences in susceptibility to meglumine antimoniate and miltefosine, and provided baseline information for monitoring susceptibility to these drugs. Sensitive and resistant clinical strains within each species, and zymodeme as a proxy marker of antimony susceptibility for L. V. panamensis, will be useful in deciphering factors involved in susceptibility and the distribution of sensitive and resistant populations.

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

    Science.gov (United States)

    Welle, F; Franz, R

    2011-01-01

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

  16. 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.

  17. 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.

  18. 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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2005-11-30

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

  20. 锑矿土壤中As和Sb的分布、形态及生物可利用性%Distribution, speciation and bio-availability of arsenic(As) and antimony (Sb) in soils of antimony mine

    Institute of Scientific and Technical Information of China (English)

    陈秋平; 胥思勤; 安艳玲; 陈洁薇; 吴贞术

    2014-01-01

    HG-AFS was applied to the determination of arsenic( As) and antimony ( Sb) in the soils near Qinglong antimony mine area with microwave assisted sample digestion. Tessier sequential extraction was used to investigate the distribution,speciation and bio-availability of As and Sb in the soils. Results showed that total arsenic content ( 17. 98-127. 85 mg·kg-1 ) and total antimony concentration (171.93-601.59 mg·kg-1) substantially exceeded their background level in Guizhou Province. The speciation of antimony and arsenic in the soils has the following distribution order:residual phase> Fe/Mn hydrous oxides, orgnic phase, carbonate fraction>cation exchangeable. The concentration of easily bioavailable antimony was 0. 60-3. 91 mg·kg-1 and the percentage was 0�33%-1.72%, while 0.15-0.48 mg·kg-1 and 0.09%-0.57% for arsenic.%采用微波消解-氢化物发生-原子荧光光谱法测定了晴隆锑矿区土壤中总砷和总锑,利用Tessier连续提取法分析土壤中不同形态砷和锑.结果表明,各采样点土壤 As、Sb 含量分别为17.98-127.85 mg·kg-1、171�93-601.59 mg·kg-1,远高于贵州省背景值;土壤中砷和锑的存在形态均以残渣态为主,其次是有机结合态、铁锰氧化物结合态和碳酸盐结合态,可交换态很少;土壤中生物可利用态锑占总和0.33%-1.72%,其含量为0.60-3.91 mg·kg-1,而土壤中生物可利用态砷占总和0.09%-0.57%,其含量为0.15-0.48 mg·kg-1.

  1. Iodide-induced thyrotoxicosis in a thyroidectomized patient with metastatic thyroid carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Yoshinari, M.; Tokuyama, T.; Okamura, K.; Sato, K.; Kusuda, K.; Fujishima, M.

    1988-04-15

    An unusual case of iodide-induced thyrotoxicosis is documented in this article. The patient was a 64-year-old euthyroid man with acromegaly. He also had multiple follicular and papillary thyroid carcinomas with a metastatic lesion in the lumbar vertebrae. After a total thyroidectomy, he became slightly hypothyroid, and the lumbar lesion began to incorporate /sup 131/I by scintigraphy. When an iodine-containing contrast medium happened to be injected, a transient increase of serum thyroid hormone level was observed. After complete thyroid ablation with 83 mCi of /sup 131/I, the oral administration of 100 mg of potassium iodide for 7 days induced a prominent increase of serum thyroid hormone level. These findings indicated that the metastatic thyroid carcinoma could produce excess thyroid hormone insofar as a sufficient amount of iodide was given. Although this is the first report of such a case, iodide-induced thyrotoxicosis may not be rare in patients with thyroid carcinomas because the Wolff-Chaikoff effect is thought to be lost, and the organic iodinating activity and lysosomal protease activity are well-preserved.

  2. Leaching of iodide (I(-)) and iodate (IO3(-)) anions from synthetic layered double hydroxide materials.

    Science.gov (United States)

    Theiss, Frederick L; Ayoko, Godwin A; Frost, Ray L

    2016-09-15

    Several studies have previously demonstrated that layered double hydroxides (LDHs) show considerable potential for the adsorption of radioiodine from aqueous solution; however, few studies have demonstrated that these materials are able to store radioactive (131)I for an acceptable period. The leaching of iodide (I(-)) and iodate (IO3(-)) form Mg/Al LDHs has been carried out. Contact time appeared to be a more significant variable for the leaching of iodate (IO3(-)) compared to that of iodide (I(-)). Experimental results are fitted to the pseudo second order model, suggesting that diffusion is likely to be the rate-limiting step. The presence of carbonate in the leaching solution appeared to significantly increase the leaching of iodide (I(-)) as did the presence of chloride to a lesser extent. The maximum amount of iodate (IO3(-)) leached using ultrapure water as the leaching solution was 21% of the iodate (IO3(-)) originally present. The corresponding result for iodide (I(-)) was even lower at 3%.

  3. Photodissociation of sodium iodide and resonant ionization of sodium atom produced

    Institute of Scientific and Technical Information of China (English)

    HUO Bing-hai; Z.T.Salim; A.H.Bakery

    2004-01-01

    Resonant ionization spectroscopy (RIS) and resonant ionization mass spectroscopy (RIMS) are employed to detect the photodissociation product of sodium iodide molecules in a molecular beam in an intense laser field in the absence of the buffer gases. Time of flight mass spectra is recorded. In particular, the appearances of multiphoton ionization are discussed.

  4. Preparation and Luminescence Thermochromism of Tetranuclear Copper(I)-Pyridine-Iodide Clusters

    Science.gov (United States)

    Parmeggiani, Fabio; Sacchetti, Alessandro

    2012-01-01

    A simple and straightforward synthesis of a tetranuclear copper(I)-pyridine-iodide cluster is described as a laboratory experiment for advanced inorganic chemistry undergraduate students. The product is used to demonstrate the fascinating and visually impressive phenomenon of luminescence thermochromism: exposed to long-wave UV light, the…

  5. The sodium iodide symporter (NIS) and potential regulators in normal, benign and malignant human breast tissue.

    LENUS (Irish Health Repository)

    Ryan, James

    2011-01-01

    The presence, relevance and regulation of the Sodium Iodide Symporter (NIS) in human mammary tissue remains poorly understood. This study aimed to quantify relative expression of NIS and putative regulators in human breast tissue, with relationships observed further investigated in vitro.

  6. Research data supporting "Photon recycling in lead-iodide perovskite solar cells"

    OpenAIRE

    Pazos-Outón, Luis M.; Szumilo, Monika; Lamboll, Robin; Richter, Johannes M.; Crespo-Quesada, Micaela; Abdi - Jalebi, Mojtaba; Beeson, Harry J.; Vrucinic, Milan; Alsari, Mejd; Snaith, Henry J.; Ehrler, Bruno; Friend, Richard H.; Deschler, Felix

    2016-01-01

    Data for the figures presented in the manuscript. These research data support “Photon recycling in lead-iodide perovskite solar cells” published in “Science” (http://dx.doi.org./10.1126/science.aaf1168) This work was supported by the EPSRC [grant number EP/M005143/1] and Winton Programme for the Physics of Sustainability.

  7. Real-Time Observation of Organic Cation Reorientation in Methylammonium Lead Iodide Perovskites

    NARCIS (Netherlands)

    Bakulin, Artem A.; Selig, Oleg; Bakker, Huib J.; Rezus, Yves L. A.; Mueller, Christian; Glaser, Tobias; Lovrincic, Robert; Sun, Zhenhua; Chen, Zhuoying; Walsh, Aron; Frost, Jarvist M.; Jansen, Thomas L. C.

    2015-01-01

    The introduction of a mobile and polarized organic moiety as a cation in 3D lead-iodide perovskites brings fascinating optoelectronic properties to these materials. The extent and the time scales of the orientational mobility of the organic cation and the molecular mechanism behind its motion remain

  8. Multiple subcutaneous mycetomas caused by Pseudallescheria boydii: response to therapy with oral potassium iodide solution.

    Science.gov (United States)

    Khan, Fida A; Hashmi, Shahrukh; Sarwari, Arif R

    2010-02-01

    We describe the case of a sixteen-year-old male who presented with multiple subcutaneous mycetomas proven on culture to be secondary to Pseudallescheria boydi., The lesions responded completely to oral potassium iodide solution. To our knowledge this has never been reported in humans.

  9. Regioselective iodination of aromatic compounds with potassium iodide in the presence of benzyltriphenylphosphonium perchlorate

    Institute of Scientific and Technical Information of China (English)

    Jalal Albadi; Masoumeh Abedini; Nasir Iravani

    2012-01-01

    A simple and efficient method for the selective iodination of various aromatic compounds by using potassium iodide in the presence of benzyltriphenylphosphonium perchlorate,is reported.This method provides several advantages such as good selectivity between ortho and para positions of aromatic compounds and high yields of the products.

  10. The Reaction between Iron(II) Iodide and Potassium Dichromate(VI) in Acidified Aqueous Solution

    Science.gov (United States)

    Talbot, Christopher

    2013-01-01

    This "Science note" teaching lesson explores the possible reaction between the ions in a reaction mixture consisting of iron(II) iodide and potassium dichromate(VI) in acidified aqueous solution. The electrode potentials will be used to deduce any spontaneous reactions under standard thermodynamic conditions (298 K, 1 bar (approximately…

  11. Relaxation of the Silver/Silver Iodide Electrode in Aqueous Solution

    NARCIS (Netherlands)

    Peverelli, K.J.

    1979-01-01

    The aim of this study is to detect and characterize relaxation processes on silver/silver iodide electrodes in aqueous electrolyte solution. The information obtained is to be used for an estimation of the consequences of similar processes on colloidal AgI particles during encounter.In chapter 1 a ge

  12. Activation of lactoperoxidase by heme-linked protonation and heme-independent iodide binding.

    Science.gov (United States)

    Toyama, Akira; Tominaga, Aya; Inoue, Tatsuo; Takeuchi, Hideo

    2010-01-01

    Lactoperoxidase (LPO), a mammalian secretory heme peroxidase, catalyzes the oxidation of thiocyanate by hydrogen peroxide to produce hypothiocyanate, an antibacterial agent. Although LPO is known to be activated at acidic pH and in the presence of iodide, the structural basis of the activation is not well understood. We have examined the effects of pH and iodide concentration on the catalytic activity and the structure of LPO. Electrochemical and colorimetric assays have shown that the catalytic activity is maximized at pH 4.5. The heme Soret absorption band exhibits a small red-shift at pH 5.0 upon acidification, which is ascribable to a structural transition from a neutral to an acidic form. Resonance Raman spectra suggest that the heme porphyrin core is slightly contracted and the Fe-His bond is strengthened in the acidic form compared to the neutral form. The structural change of LPO upon activation at acidic pH is similar to that observed for myeloperoxidase, another mammalian heme peroxidase, upon activation at neutral pH. Binding of iodide enhances the catalytic activity of LPO without affecting either the optimum pH of activity or the heme structure, implying that the iodide binding occurs at a protein site away from the heme-linked protonation site.

  13. Distribution of bromine in mixed iodide-bromide organolead perovskites and its impact on photovoltaic performance

    NARCIS (Netherlands)

    Zhou, Yang; Wang, Feng; Fang, Hong-Hua; Loi, Maria Antonietta; Xie, Fang-Yan; Zhao, Ni; Wong, Ching-Ping

    2016-01-01

    Mixed iodide-bromide (I-Br) organolead perovskites are of great interest for both single junction and tandem solar cells since the optical bandgap of the materials can be tuned by varying the bromine to iodine ratio. Yet, it remains unclear how bromine incorporation modifies the properties of the pe

  14. Photoexcitation dynamics in solution-processed formamidinium lead iodide perovskite thin films for solar cell applications

    NARCIS (Netherlands)

    Fang, Hong-Hua; Wang, Feng; Adjokatse, Sampson; Zhao, Ni; Even, Jacky; Loi, Maria Antonietta

    2016-01-01

    Formamidinium lead iodide (FAPbI(3)) is a newly developed hybrid perovskite that potentially can be used in high-efficiency solution-processed solar cells. Here, the temperature-dependent dynamic optical properties of three types of FAPbI(3) perovskite films (fabricated using three different precurs

  15. Pharmacokinetic and parasitological evaluation of the bone marrow of dogs with visceral leishmaniasis submitted to multiple dose treatment with liposome-encapsulated meglumine antimoniate

    Directory of Open Access Journals (Sweden)

    D.A. Schettini

    2005-12-01

    Full Text Available The aim of the present study was to evaluate the impact of a multiple dose regimen of a liposomal formulation of meglumine antimoniate (LMA on the pharmacokinetics of antimony in the bone marrow of dogs with visceral leishmaniasis and on the ability of LMA to eliminate parasites from this tissue. Dogs naturally infected with Leishmania chagasi received 4 intravenous doses of either LMA (6.5 mg antimony/kg body weight, N = 9, or empty liposomes (at the same lipid dose as LMA, N = 9 at 4-day intervals. A third group of animals was untreated (N = 8. Before each administration and at different times after treatment, bone marrow was obtained and analyzed for antimony level (LMA group by electrothermal atomic absorption spectrometry, and for the presence of Leishmania parasites (all groups. There was a significant increase of antimony concentration from 0.76 µg/kg wet organ (4 days after the first dose to 2.07 µg/kg (4 days after the fourth dose and a half-life of 4 days for antimony elimination from the bone marrow. Treatment with LMA significantly reduced the number of dogs positive for parasites (with at least one amastigote per 1000 host cells compared to controls (positive dogs 30 days after treatment: 0 of 9 in the LMA group, 3 of 9 in the group treated with empty liposomes and 3 of 8 in the untreated group. However, complete elimination of parasites was not achieved. In conclusion, the present study showed that multiple dose treatment with LMA was effective in improving antimony levels in the bone marrow of dogs with visceral leishmaniasis and in reducing the number of positive animals, even though it was not sufficient to achieve complete elimination of parasites.

  16. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Carey, John J.; Allen, Jeremy P. [School of Chemistry and CRANN, Trinity College Dublin, Dublin 2 (Ireland); Scanlon, David O. [University College London, Kathleen Lonsdale Materials Chemistry, 20 Gordon Street, London WC1H 0AJ (United Kingdom); Diamond Light Source Ltd., Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom); Watson, Graeme W., E-mail: watsong@tcd.ie [School of Chemistry and CRANN, Trinity College Dublin, Dublin 2 (Ireland)

    2014-05-01

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

  18. Local bonding structure of tellurium and antimony in the phase change chalcogenides germanium-antimony-tellurium: A nuclear magnetic resonance study

    Science.gov (United States)

    Bobela, David C.

    Recent technological applications of some chalcogenide materials, compounds containing a group VI atom, have prompted studies of the local atomic structure of the amorphous phase. In the case of Ge2Sb2Te 5, metastability in the local bonding structure is responsible for its usefulness as a phase-change memory material. There is no consensus on the exact phase-change mechanism, which is partly due to the inadequacy of standard scattering techniques to probe the structure of the amorphous phase. Nuclear magnetic resonance methods, on the other hand, are well suited to study local structural order even in the absence of a periodic lattice. In this technique, structural information is encoded as an oscillating voltage caused by the nuclear spin. For the tellurium isotope, 125Te (spin = 1/2 in the ground state), the dominant interaction comes from the core and valence electrons that carry angular momentum. This interaction is helpful in identifying Te sites of different local coordination since the number of neighboring atoms should markedly change the local electronic structure. The antimony isotope 125Sb has a spin = 5/2 in the ground state and possesses an asymmetric nuclear charge. This quadrupole moment will interact with an electric field gradient at the nuclear site, which is provided by an asymmetric electron cloud surrounding the nucleus. The frequency-space spectra will reflect the strength of the interaction as well as the symmetry of the local electronic environment. This work investigates the nuclear magnetic resonance spectrum of 125Te and 125Sb in the crystalline and amorphous forms of several GexSbyTe 1-x-y compounds where 0 arranged such that the constituent elements have enough bonds, on average, to satisfy their valence requirement. The implications of the NMR data on theoretical modeling data are immediate. Theoretical models of these systems must possess some aspect of the "8-n" mentality. With this idea as a foundation for physically realistic

  19. Experimental study on iodine chemistry (EXSI) - Containment experiments with methyl iodide

    Energy Technology Data Exchange (ETDEWEB)

    Holm, J.; Ekberg, C. (Chalmers Univ. of Technology, Goeteborg (Sweden)); Kaerkelae, T.; Auvinen, A. (VTT, Espoo (Finland)); Glaenneskog, H. (Vattenfall Power Consultant, Goeteborg (Sweden))

    2011-05-15

    An experimental study on radiolytic decomposition of methyl iodide was conducted in co-operation between VTT and Chalmers University of Technology as a part of the NKS-R programs. In year 2008 the NROI project, a Nordic collaboration studying iodine chemistry in the containment, was started. During year 2008 (NROI-1) the radiolytic oxidation of elemental iodine was investigated and during 2009 (NROI-2), the radiolytic oxidation of organic iodine was studied. This project (NROI-3) is a continuation of the investigation of the oxidation of organic iodine. The project has been divided into two parts. 1. The aims of the first part were to investigate the effect of ozone and UV-radiation, in dry and humid conditions, on methyl iodide. 2. The second project was about gamma radiation (approx20 kGy/h) and methyl iodide in dry and humid conditions. 1. Experimental results showed that the methyl iodide concentration in the facility was reduced with increasing temperature and increasing UV-radiation intensity. Similar behaviour occurred when ozone was present in the system. Formed organic gas species during the decomposition of methyl iodide was mainly formaldehyde and methanol. The particle formation was instant and extensive when methyl iodide was exposed to ozone and/or radiation at all temperatures. The size of the formed primary particles was about 10 nm and the size of secondary particles was between 50-200 nm. From the SEM-EDX analyses of the particles, the conclusion was drawn that these were some kind of iodine oxides (I{sub xO{sub y}). However, the correct speciation of the formed particles was difficult to obtain because the particles melted and fused together under the electron beam. 2. The results from this sub-project are more inconsistent and hard to interpret. The particle formation was significant lesser than corresponding experiments when ozone/UV-radiation was used instead of gamma radiation. The transport of gaseous methyl iodide through the facility was

  20. Conversion of Iodide to Hypoiodous Acid and Molecular Iodine at the Air-Water Interface

    Science.gov (United States)

    Pillar, E. A.; Guzman, M. I.

    2013-12-01

    Sea spray aerosols continuously transfer a significant amount of halides to the marine boundary layer, where they play a major role in the depletion of tropospheric ozone. The reactivity of iodide is of special interest in sea spray aerosols, where this species is enriched relative to chloride and bromide in surface seawater. This work presents laboratory experiments that provide mechanistic information to understand the reactivity of halides in atmospheric aerosols. Pneumatically assisted electrospray is used to aerosolize solutions of sodium iodide (0.01-100 μM), which are rapidly (~3 μs) oxidized by ozone at 25 °C. Reaction products include HIO, IO2-, IO3-, I2, HI2O-, and I3-, all identified by mass spectrometry. The distribution of products varies along two different reaction pathways, one favoring the production of I2 and HIO for typical tropospheric ozone levels (~50 ppbv), and another one directed to the production of IO3- at higher oxidizer concentrations. The formation of products increases exponentially with rising concentrations of initial sodium iodide, [NaI]0. The process is determined to be pH independent for the pH range 6-8 representative of surface waters. The substitution of aqueous solutions by organic solvents, such as methanol or acetonitrile, causes a decrease in the surface tension and lifetime of the droplets, leading to larger I2 production. The presence of surface active organic compounds, which alter the structure of the interfacial region, promote the pathway of I2 formation over IO3-. In conclusion, this presentation will show how the oxidation of iodide in aqueous microdroplets can release reactive gas-phase species, such as I2 and HIO, capable to affect tropospheric ozone globally. Normalized intensity of products observed during the ozonolysis of iodide solutions at 130 ppbv ozone. Cone voltage = 70 V, needle voltage = 2.5 kV.

  1. [The application of eosin and propidium iodide in evaluation of vitality of human spermatozoa].

    Science.gov (United States)

    Ploskonos, М В

    2014-11-01

    The article analyzes comparative assessment of vitality of spermatozoa by condition of permeability of membranes for eosin and propidium iodide and comparison of results acquired using technique of light and fluorescent microscopy. The comparison of data of light microscopy with eosin staining with data of fluorescent microscopy with propidium iodide staining demonstrated that percentage of content of spermatozoa separated from ejaculates of 28 fertile males and stained with eosin was reliably higher (34.8 ± 3.2) than percentage of content of spermatozoa with stained with propidium iodide (2.1 ± 4.0). After incubation of spermatozoa under room temperature during 24 hours percentage of unviable cells with stained eosin also was higher than in case of propidium iodide staining correspondingly (44.5 ± 3.3% and 34.7 ± 3.6%). The analysis of vitality of spermatozoa under damaging effect of oxidative stress on cell membrane developed by 4 hours incubation with 200 mkM of hydrogen peroxide (H2O2) demonstrated that under staining of spermatozoa with propidium iodide significantly higher percentage of damaged cells is detected. In such cases, eosin staining is less suitable for detection of vitality of spermatozoa (73.6 ± 5.8% against 51.7 ± 6.4%). The carried out experiment demonstrates that in case of detected effects on spermatozoa (for example, effect of oxidative stress) the light microscopy insufficiently adequate reflects degree of damage of membranes of spermatozoa. The fluorescent microscopy detects a higher percentage of spermatozoa with damaged membrane.

  2. 碘化物对金精矿碘化浸出过程的影响%Effects of different iodides on gold concentrates leaching process in iodine­iodide solution

    Institute of Scientific and Technical Information of China (English)

    李绍英; 王海霞; 孙春宝; 赵留成; 阎志强

    2013-01-01

    Using the iodine­iodide leaching system, the effects of different iodides (ammonium iodide,potassium iodide, hydrogen iodide)on gold concentrates leaching process were discussed from the influence factors, such as initial iodine content, iodine and iodide ratio and solution pH value. The results show that, when ammonium iodide or potassium iodide is used as complex agent,under the conditions of initial iodine content of 1%, iodine and iodide molar ratio of 1:8, pH value of 7, liquid­solid ratio of 4:1, stirring speed of 600 r/min, leaching time of 4 h and temperature of 25℃, the gold leaching rates are around 90%;whereas the gold leaching effect is poorer when hydrogen iodide(aqueous solution is hydroiodic acid) is used as complex agent, and the gold leaching rate is only 75%. Considering the difference of leaching effect and availability of industry and so on,potassium iodide is the suitable complex reagent of gold concentrate leaching in iodine­iodide solution.%  采用碘−碘化物浸出体系,从碘初始含量、碘与碘化物摩尔比和浸出液pH值3个影响因素入手,考察不同碘化物(碘化铵、碘化钾和碘化氢)对金精矿碘化浸出过程的影响。结果表明:在碘初始含量为1%,碘与碘化物摩尔比为1:8,浸出液pH值为7,液固比为4:1,搅拌速度为600 r/min,浸出时间为4 h,温度为25℃的条件下,用碘化铵或碘化钾作为碘化浸金的络合剂,金的浸出率均能达到90%左右,而用碘化氢(其水溶液为氢碘酸)作络合剂时,金的浸出率仅有75%。考虑到不同碘化物浸金效果差异及工业应用的可行性等因素,确定碘化钾为适宜的金精矿碘化浸出络合剂。

  3. 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.

  4. Effect of antimony addition on the optical behaviour of germanium selenide thin films

    Science.gov (United States)

    Sharma, Parikshit; Rangra, V. S.; Sharma, Pankaj; Katyal, S. C.

    2008-11-01

    This paper reports the influence of antimony (Sb) addition on the optical properties (optical energy gap and refractive index) of thin solid films of the chalcogenide glassy Ge0.17Se0.83-xSbx(x = 0, 0.03, 0.09, 0.12, 0.15) system. This has been done by analysing the transmittance (T) and reflectance (R) spectra in the spectral region 400-2000 nm. It was found that the optical energy gap decreases with increasing Sb content from 1.92 to 1.63 eV with an uncertainty of ± 0.01 eV. The results were interpreted in terms of bond energies and on the basis of the concept of electronegativity. The refractive index has been found to increase with increasing Sb content. The increase in the refractive index has been explained on the basis of polarizability. Dispersion of refractive index has been analysed using the Wemple-DiDomenico single oscillator model. The static refractive index increased from 2.45 to 2.91 for the studied compositions. An estimate of the energy gap has also been taken theoretically and it has been found that both the optical energy gap (measured from T and R spectra) and the theoretical energy gap follow similar trends.

  5. Effect of antimony addition on the optical behaviour of germanium selenide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Parikshit; Rangra, V S [Department of Physics, H. P. University, Summer Hill, Shimla (171005) (India); Sharma, Pankaj; Katyal, S C [Department of Physics, Jaypee University of Information Technology, Waknaghat, Solan, H.P. (173215) (India)], E-mail: pankaj.sharma@juit.ac.in, E-mail: sharma_parikshit@yahoo.com

    2008-11-21

    This paper reports the influence of antimony (Sb) addition on the optical properties (optical energy gap and refractive index) of thin solid films of the chalcogenide glassy Ge{sub 0.17}Se{sub 0.83-x}Sb{sub x}(x = 0, 0.03, 0.09, 0.12, 0.15) system. This has been done by analysing the transmittance (T) and reflectance (R) spectra in the spectral region 400-2000 nm. It was found that the optical energy gap decreases with increasing Sb content from 1.92 to 1.63 eV with an uncertainty of {+-} 0.01 eV. The results were interpreted in terms of bond energies and on the basis of the concept of electronegativity. The refractive index has been found to increase with increasing Sb content. The increase in the refractive index has been explained on the basis of polarizability. Dispersion of refractive index has been analysed using the Wemple-DiDomenico single oscillator model. The static refractive index increased from 2.45 to 2.91 for the studied compositions. An estimate of the energy gap has also been taken theoretically and it has been found that both the optical energy gap (measured from T and R spectra) and the theoretical energy gap follow similar trends.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  11. 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.

  12. 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.

  13. 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.

  14. Stepwise mechanism of oxidative ammonolysis of propane to acrylonitrile over gallium-antimony oxide catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Osipova, Z.G.; Sokolovskii, V.D.

    1979-03-01

    The stepwise mechanism of oxidative ammonolysis of propane to acrylonitrile over gallium-antimony oxide catalysts GaSb/sub 19/O/sub x/, GaSb/sub 3/Ni/sub 1.5/0/sub x/, and GaSb/sub 2.5/Ni/sub 1.5/PW/sub 0//sub 0.25/O/sub x/ was studied at 450/sup 0/ and 550/sup 0/C by introducing alternating pulses of 0.5Vertical Bar3< propane/0.6Vertical Bar3< ammonia/helium (to reduce the steady-state catalytic surface) and 0.5Vertical Bar3< propane/0.6Vertical Bar3< ammonia/1.86Vertical Bar3< oxygen/helium mixtures into a fluidized-bed catalytic reactor. Over all the catalysts studied, the rates of acrylonitrile formation during the two types of pulses were very similar, but carbon dioxide was formed much faster during the reducing pulses, particularly at 450/sup 0/C. These findings suggested that acrylonitrile is formed by a stepwise redox mechanism involving consecutive interaction of propane and ammonia with the surface oxygen of the catalysts and oxidation of the reduced catalyst surface by gas-phase oxygen. The formation of carbon dioxide proceeds by both stepwise and associative mechanisms, the latter being more important at higher temperatures. The results are similar to published results for ammoxidation of propylene and olefins.

  15. 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.

  16. 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

    2013-12-03

    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.

  17. Radioactive iodide (131 I-) excretion profiles in response to potassium iodide (KI) and ammonium perchlorate (NH4ClO4) prophylaxis.

    Science.gov (United States)

    Harris, Curtis; Dallas, Cham; Rollor, Edward; White, Catherine; Blount, Benjamin; Valentin-Blasini, Liza; Fisher, Jeffrey

    2012-08-01

    Radioactive iodide ((131)I-) protection studies have focused primarily on the thyroid gland and disturbances in the hypothalamic-pituitary-thyroid axis. The objective of the current study was to establish (131)I- urinary excretion profiles for saline, and the thyroid protectants, potassium iodide (KI) and ammonium perchlorate over a 75 hour time-course. Rats were administered (131)I- and 3 hours later dosed with either saline, 30 mg/kg of NH(4)ClO(4) or 30 mg/kg of KI. Urinalysis of the first 36 hours of the time-course revealed that NH(4)ClO(4) treated animals excreted significantly more (131)I- compared with KI and saline treatments. A second study followed the same protocol, but thyroxine (T(4)) was administered daily over a 3 day period. During the first 6-12 hour after (131)I- dosing, rats administered NH(4)ClO(4) excreted significantly more (131)I- than the other treatment groups. T(4) treatment resulted in increased retention of radioiodide in the thyroid gland 75 hour after (131)I- administration. We speculate that the T(4) treatment related reduction in serum TSH caused a decrease synthesis and secretion of thyroid hormones resulting in greater residual radioiodide in the thyroid gland. Our findings suggest that ammonium perchlorate treatment accelerates the elimination rate of radioiodide within the first 24 to 36 hours and thus may be more effective at reducing harmful exposure to (131)I- compared to KI treatment for repeated dosing situations. Repeated dosing studies are needed to compare the effectiveness of these treatments to reduce the radioactive iodide burden of the thyroid gland.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1992-12-31

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

  19. 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

  20. Experimental study on iodine chemistry (EXSI) - Containment experiments with methyl iodide

    Energy Technology Data Exchange (ETDEWEB)

    Holm, J.; Glaenneskog, H.; Ekberg, C. (Chalmers Univ. of Technology (Sweden)); Kaerkelae, T.; Auvinen, A. (VTT Technical Research Centre of Finland (Finland))

    2010-05-15

    An experimental study on radiolytic decomposition of methyl iodide was conducted in co-operation between VTT and Chalmers University of Technology as a part of the NKS-R programs. The behaviour of iodine during a severe accident has been studied in several experimental programs, ranging from the large-scale PHEBUS FP tests and intermediate-scale ThAI tests to numerous separate effect studies. In year 2008 the NROI project, a Nordic collaboration studying iodine chemistry in the containment was started. During 2009, oxidation of iodine, especially organic iodine, was studied within the NROI project. The chemistry of organic iodine in the gas phase is still one of the greatest remaining uncertainties concerning iodine behaviour during a severe accident. During the first year of the NROI project the oxidation of elemental iodine, I2, with ozone and UV-light was investigated. In this study organic iodide, in this case methyl iodide, was investigated in similar conditions as in the NROI-1 project. The experimental facility applied in this study is based on the sampling system built at VTT for the ISTP project CHIP conducted by IRSN. The experimental facility and the measuring technology are sophisticated and unique in the area of nuclear research as well as in the field of aerosol science. Experimental results showed that the methyl iodide concentration in the facility was reduced with increasing temperature and increasing UVC intensity. Similar behaviour occurred when ozone was present in the system. Formed organic gas species during the decomposition of methyl iodide was mainly formaldehyde and methanol. Instant and extensive particle formation occurred when methyl iodide was transported through a UVC radiation field and/or when ozone was present. The size of the formed primary particles was about 10 nm and the size of secondary particles was between 50-150 nm. From the SEM-EDX analyses of the particles, the conclusion was drawn that these were some kind of iodine

  1. 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...

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

    Directory of Open Access Journals (Sweden)

    Cesar Miranda-Verastegui

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

  3. Cooperative effect of silver in copper-catalyzed trifluoromethylation of aryl iodides using Me3SiCF3

    KAUST Repository

    Weng, Zhiqiang

    2011-06-13

    An effective model of cooperative effect of silver for the coppercatalyzed trifluoromethylation of activated and unactivated aryl iodides to trifluoromethylated arenes using Me3SiCF3 was achieved with a broad substrate scope. © 2011 American Chemical Society.

  4. Formation of iodinated disinfection by-products during oxidation of iodide-containing water with potassium permanganate.

    Science.gov (United States)

    Ye, Tao; Xu, Bin; Lin, Yi-Li; Hu, Chen-Yan; Xia, Sheng-Ji; Lin, Lin; Mwakagenda, Seleli Andrew; Gao, Nai-Yun

    2012-11-30

    This study shows that iodinated disinfection by-products (I-DBPs) including iodoform (IF), iodoacetic acid (IAA) and triiodoacetic acid (TIAA) can be produced when iodide-containing waters are in contact with potassium permanganate. IF was found as the major I-DBP species during the oxidation. Iodide was oxidized to HOI, I(2) and I(3)(-), consequently, which led to the formation of iodinated organic compounds. I-DBPs varied with reaction time, solution pH, initial concentrations of iodide and potassium permanganate. Yields of IF, IAA and TIAA increased with reaction time and considerable I-DBPs were formed within 12 h. Peak IF yields were found at circumneutral pH range. However, formation of IAA and TIAA was favored under acidic conditions. Molar ratio of iodide to potassium permanganate showed significant influence on formation of IF, IAA and TIAA. The formation of IF, IAA and TIAA also depended on the characteristics of the waters.

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

    Directory of Open Access Journals (Sweden)

    Jairo E Perez-Franco

    2016-05-01

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

  6. 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.

  7. 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

  8. Gap energy studied by optical transmittance in lead iodide monocrystals grown by Bridgman's Method

    Directory of Open Access Journals (Sweden)

    Veissid N.

    1999-01-01

    Full Text Available The bandgap energy as a function of temperature has been determined for lead iodide. The monocrystal was obtained in a vacuum sealed quartz ampoule inside a vertical furnace by Bridgman's method. The optical transmittance measurement enables to evaluate the values of Eg. By a fitting procedure of Eg as a function of temperature is possible to extract the parameters that govern its behavior. The variation of Eg with temperature was determined as: Eg(T = Eg(0 - aT2/(a + T, with: Eg(0 = (2.435 ± 0.008 eV, a = (8.7 ± 1.3 x 10-4 eV/K and a = (192 ± 90 K. The bandgap energy of lead iodide at room temperature was found to be 2.277 ± 0.007 eV.

  9. Induction of iodide uptake in transformed thyrocytes: a compound screening in cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Froehlich, Eleonore [University of Tuebingen, Department of Endocrinology, Metabolism, Nephrology and Clinical Chemistry, Internal Medicine, Tuebingen (Germany); Brossart, Peter [University of Tuebingen, Department of Haematology, Oncology, Immunology and Rheumatology, Internal Medicine, Tuebingen (Germany); Wahl, Richard [University of Tuebingen, Department of Endocrinology, Metabolism, Nephrology and Clinical Chemistry, Internal Medicine, Tuebingen (Germany); Department IV, Internal Medicine, Tuebingen (Germany)

    2009-05-15

    Retinoic acid presently is the most advanced agent able to improve the efficacy of radioiodine therapy in differentiated thyroid carcinoma. In order to identify compounds with higher efficacy a panel of pharmacologically well-characterized compounds with antitumour action in solid cancer cell lines was screened. The effects of the compounds on iodide uptake, cell number, proliferation and apoptosis were evaluated. In general, compounds were more effective in cell lines derived from more aggressive tumours. The effectiveness in terms of number of responsive cell lines and maximal increase in iodide uptake achieved decreased in the order: APHA > valproic acid {approx} sirolimus {approx} arsenic trioxide > retinoic acid {approx} lovastatin > apicidine {approx} azacytidine {approx} retinol {approx} rosiglitazone {approx} bortezomib. We hypothesize that testing of cells from primary tumours or metastases in patients may be a way to identify compounds with optimum therapeutic efficacy for individualized treatment. (orig.)

  10. Preparation,Characterization and Optical Properties of Hostguest Nanocomposite Material Mordenite—silver Iodide

    Institute of Scientific and Technical Information of China (English)

    ZHAIQing-zhou; QIUShi-lun

    2003-01-01

    Silver iodide nanoclusters were successfully prepared in the channels of mordenite by a heat diffusion method.Powder X-ray diffraction.adsorption technique and infrared spectroscopy were used to characterize the prepared materials,which showed that the guest silver iodied had been encapsulated in the channels of mordenite.The optical properties of the solid phase diffuse reflectance absorption of nanocomposite material NaM-AgI were studied,showing that the absorption bands of the diffuse reflectance absorption of the prepared material moved to the region of high energy.The absorption peak of the material prepared shifted to the region of high energy.Namely,blue shift was caused.This has demonstrated the incorporation of silver iodide into the channels of the zeolite.We observed the luminescence and surface photovoltage spectra of NaM-AgI sample,proposing the mechanisms of the photoluminescence and photovoltaic responses.

  11. Solvatochromic effect and kinetics of methyl violet reduction with potassium iodide in water-isopropanol mixtures

    Science.gov (United States)

    Ashfaq, Maria; Saeed, Rehana; Khan, Sameera Razi; Masood, Summyia

    2016-12-01

    The solvent influence on the reduction kinetics of methyl violet with iodide in binary mixture of aqueous isopropanol was investigated spectrophotometrically. The absorption spectra of methyl violet were recorded in water, aqueous isopropanol and absolute isopropanol. In these solvents λmax was in the range from 580.5 to 582.5 nm. The CNIBS/R-K model was used to calculate the solvatochromic parameters in a binary mixture; polynomial equation was also applied to describe the experimental data. The transition energies ( E T) were calculated. They show bathochromic shift with the decrease in the polarity of the solvent. The temperature was varied from 298-318 K, while the pH of the reaction was maintained at 4.99 and 6.00. The reduction reaction was found to be first order by potassium iodide and zero order by methyl violet. The thermodynamic parameters were also evaluated to support the kinetic data.

  12. Crystal structure of catena-poly[[potassium-tri-μ-dimethylacetamide-κ6O:O] iodide

    Directory of Open Access Journals (Sweden)

    Cezar-Catalin Comanescu

    2014-10-01

    Full Text Available The structure of catena-poly[[potassium-tri-μ-dimethylacetamide-κ6O:O] iodide], {[K(C4H9NO3]I}n, at 120 K has trigonal (P-3 symmetry. The structure adopts a linear chain motif parallel to the crystallographic c axis. Two crystallographically independent K+ cations are present in the asymmetric unit located on threefold rotoinversion axes at [0, 0, 0] and [0, 0, 1/2] and are bridged by the O atoms of the acetamide moiety. This is an example of a rare μ2-bridging mode for dimethylacetamide O atoms. The iodide counter-ion resides on a threefold rotation axis in the channel formed by the [K(C4H9NO]+ chains.

  13. Gastro-intestinal basidiobolomycosis in a 2-year-old boy: dramatic response to potassium iodide.

    Science.gov (United States)

    Sanaei Dashti, Anahita; Nasimfar, Amir; Hosseini Khorami, Hossein; Pouladfar, Gholamreza; Kadivar, Mohammad Rahim; Geramizadeh, Bita; Khalifeh, Masoomeh

    2016-07-04

    Gastro-intestinal basidiobolomycosis (GIB) is a rare fungal infection caused by Basidiobolus ranarum. Treatment includes surgical resection and long-term antifungal therapy. A 2.5-year-old boy presented with a 10-day history of abdominal pain, fever and diarrhoea, and a palpable abdominal mass was detected. Resection was undertaken and histology confirmed basidiobolomycosis. Treatment with amphotericin B and itraconazole was commenced, but the infection progressed and spread to involve the intestines, liver, ribs and lung, and also the abdominal wall after 6 months, requiring four operative procedures. Because of unresponsiveness to amphotericin and itraconazole, oral potassium iodide was added which resulted in complete resolution of the infection. Potassium iodide is an essential component of the treatment of systemic B. ranarum.

  14. Conclusion on the peer review of the pesticide risk assessment of the active substance potassium iodide

    Directory of Open Access Journals (Sweden)

    European Food Safety Authority

    2013-06-01

    Full Text Available The conclusions of the European Food Safety Authority (EFSA following the peer review of the initial risk assessments carried out by the competent authority of the rapporteur Member State the Netherlands, for the pesticide active substance potassium iodide are reported. The context of the peer review was that required by Commission Regulation (EU No 188/2011. The conclusions were reached on the basis of the evaluation of the representative uses of potassium iodide as a fungicide on tomatoes, sweet peppers, cucumber, eggplant, strawberries and ornamental flowers in greenhouse and field applications on strawberries. The reliable endpoints concluded as being appropriate for use in regulatory risk assessment, derived from the available studies and literature in the dossier peer reviewed, are presented. Missing information identified as being required by the regulatory framework is listed. Concerns are identified.

  15. Co-leaching of brominated compounds and antimony from bottled water.

    Science.gov (United States)

    Andra, Syam S; Makris, Konstantinos C; Shine, James P; Lu, Chensheng

    2012-01-01

    A fast-growing bottled water market is occasionally challenged by reports calling for contaminant leaching from water-contact materials (plastics). Our focus was on leaching of antimony (Sb) and brominated compounds expressed by total soluble bromine (Br) measurements, including those of polybrominated diphenyl ethers (PBDE). Studies are lacking on concomitant leaching of two or more inorganic plastic constituents from the same bottle. A market-representative basket survey of bottled water was initiated in Boston, USA supermarkets. Bottled water classes sampled were: i) non-carbonated (NCR), ii) carbonated (CR), and iii) non-carbonated and enriched (NCRE). Plastic bottle materials sampled were: polyethylene terephthalate (PET), high-density polyethylene (HDPE), polystyrene (PS), and polycarbonate (PC). Storage conditions for the 31 bottled water samples were: 23°C temperature, no-shaking and 12h/12h light/dark for 60days of equilibration. Average Br and Sb concentrations after 60-days of storage followed the order of NCR

  16. 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.

  17. Records of anthropogenic antimony in the glacial snow from the southeastern Tibetan Plateau

    Science.gov (United States)

    Zhang, Yulan; Kang, Shichang; Chen, Pengfei; Li, Xiaofei; Liu, Yajun; Gao, Tanguang; Guo, Junming; Sillanpää, Mika

    2016-12-01

    Antimony (Sb) is a ubiquitous element in the environment that is potentially toxic at very low concentrations. In this study, surface snow/ice and snowpit samples were collected from four glaciers in the southeastern Tibetan Plateau in June 2015. The concentrations of Sb and other elements were measured in these samples. The results showed that the average concentration of Sb was approximately 2.58 pg g-1 with a range of 1.64-9.20 pg g-1. The average Sb concentration in the study area was comparable to that recorded in a Mt. Everest ice core and higher than that in Arctic and Antarctic snow/ice but much lower than that in Tien Shan and Alps ice cores. Sb presented different variations with other toxic elements (Pb and Cr) and a crustal element (Al) in the three snowpits, which indicated the impact of a different source or post-deposition processes. The enrichment factor of Sb was larger than 10, suggesting that anthropogenic sources provided important contributions to Sb deposition in the glaciers. The Sb in the glacial snow was mainly loaded in the fourth component in principal component analysis, exhibiting discrepancies with crustal elements (Fe and Ca) and other toxic metals (Pb). Backward trajectories revealed that the air mass arriving at the southeastern Tibetan Plateau mostly originated from the Bay of Bengal and the South Asia in June. Thus, pollutants from the South Asia could play an important role in Sb deposition in the studied region. The released Sb from glacier meltwater in the Tibetan Plateau and surrounding areas might pose a risk to the livelihoods and well-being of those in downstream regions.

  18. Antimony (Sb) contaminated shooting range soil: Sb mobility and immobilization by soil amendments.

    Science.gov (United States)

    Okkenhaug, Gudny; Amstätter, Katja; Lassen Bue, Helga; Cornelissen, Gerard; Breedveld, Gijs D; Henriksen, Thomas; Mulder, Jan

    2013-06-18

    Antimony (Sb) in lead bullets poses a major environmental risk in shooting range soils. Here we studied the effect of iron (Fe)-based amendments on the mobility of Sb in contaminated soil from shooting ranges in Norway. Untreated soil showed high Sb concentrations in water extracts from batch tests (0.22-1.59 mg L(-1)) and soil leachate from column tests (0.3-0.7 mg L(-1)), occurring exclusively as Sb(V). Sorption of Sb to different iron-based sorbents was well described by the Freundlich equation (Fe2(SO4)3, log KF = 6.35, n = 1.51; CFH-12 (Fe oxyhydroxide), log KF = 4.16-4.32, n = 0.75-0.76); Fe(0) grit, log KF = 3.26, n = 0.47). These sorbents mixed with soil (0.5 and 2% w/w), showed significant sorption of Sb in batch tests (46-92%). However, for Fe2(SO4)3 and CFH-12 liming was also necessary to prevent mobilization of lead, copper, and zinc. Column tests showed significant retention of Sb (89-98%) in soil amended with CFH-12 (2%) mixed with limestone (1%) compared to unamended soil. The sorption capacity of soils amended with Fe(0) (2%) increased steadily up to 72% over the duration period of the column test (64 days), most likely due to the gradual oxidation of Fe(0) to Fe oxyhydroxides. Based on the experimental results, CFH-12 and oxidized Fe(0) are effective amendments for the stabilization of Sb in shooting range soils.

  19. Studies of antimony telluride and copper telluride films electrodeposition from choline chloride containing ionic liquids

    Energy Technology Data Exchange (ETDEWEB)

    Catrangiu, Adriana-Simona; Sin, Ion [Department of Inorganic Chemistry, Physical Chemistry and Electrochemistry, POLITEHNICA University of Bucharest, Calea Grivitei 132, Bucharest (Romania); Prioteasa, Paula [INCDIE ICPE-Advanced Research, Splaiul Unirii 313, Bucharest (Romania); Cotarta, Adina [Department of Inorganic Chemistry, Physical Chemistry and Electrochemistry, POLITEHNICA University of Bucharest, Calea Grivitei 132, Bucharest (Romania); Cojocaru, Anca, E-mail: a_cojocaru@chim.upb.ro [Department of Inorganic Chemistry, Physical Chemistry and Electrochemistry, POLITEHNICA University of Bucharest, Calea Grivitei 132, Bucharest (Romania); Anicai, Liana [Center of Surface Science and Nanotechnology, University POLITEHNICA of Bucharest, Splaiul Independentei 313, Bucharest (Romania); Visan, Teodor [Department of Inorganic Chemistry, Physical Chemistry and Electrochemistry, POLITEHNICA University of Bucharest, Calea Grivitei 132, Bucharest (Romania)

    2016-07-29

    Cyclic voltammetry and electrochemical impedance spectroscopy were used to investigate the deposition of antimony telluride or copper telluride from ionic liquid consisting in mixture of choline chloride with oxalic acid. In addition, the cathodic process during copper telluride formation was studied in the mixture of choline chloride with ethylene glycol. The results indicate that the Pt electrode is first covered with a Te layer, and then the more negative polarisation leads to the deposition of Sb{sub x}Te{sub y} or Cu{sub x}Te{sub y} semiconductor compounds. Thin films were deposited on copper and carbon steel at 60–70 °C and were characterised by scanning electron microscopy, energy X-ray dispersive spectroscopy (EDS), and X-ray diffraction (XRD). Their stoichiometry depends on the bath composition and applied potential. EDS and XRD patterns indicate the possible synthesis of stoichiometric Sb{sub 2}Te{sub 3} phase and Cu{sub 2}Te, Cu{sub 5}Te{sub 3}, and Cu{sub 2.8}Te{sub 2} phases, respectively, by controlling the ratio of ion concentrations in ionic liquid electrolytes and deposition potential. - Highlights: • Sb{sub x}Te{sub y} and Cu{sub x}Te{sub y} films electrodeposited from choline-chloride-based ionic liquids. • The stoichiometry of film depends on the bath composition and deposition potential. • Sb{sub 2}Te{sub 3}, Cu{sub 2}Te, Cu{sub 5}Te{sub 3}, Cu{sub 2.8}Te{sub 2} phases were identified in X-ray diffraction patterns.

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

    Science.gov (United States)

    Luo, Jinming; Bai, Yaohui; Liang, Jinsong; Qu, Jiuhui

    2014-01-01

    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.

  1. TiO2 crystal facet-dependent antimony adsorption and photocatalytic oxidation.

    Science.gov (United States)

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

    2017-02-24

    Anatase TiO2 crystal facets are garnering increasing attention due to their unique surface property. However, no specific linear relationship had been derived between the facet exposed on TiO2 and the surface adsorption capacity as well as photocatalytic performance. This study systematically explored the facet effects on antimony (Sb) adsorption and photocatalytic oxidation using high-index {201} and low-index {101}, {001}, and {100} TiO2. The results suggest that high-index {201} TiO2 exhibits the best Sb(III) adsorption and photocatalytic activity compared to the low-index TiO2. Both the Sb(III) adsorption density and the amount of OH and O2(-) generated in solution were correlated to the magnitude of surface energy on TiO2 facets. Photocatalytically generated OH and O2(-) were responsible for Sb(III) photooxidation as evidenced by radical-trapping experiments. The great contribution of OH was observed only on {201}, not on low-index TiO2. This phenomenon was found to be attributable to the high surface energy on {201}, which enables the generation of a large amount of photogeneration OH to compensate for the fast rate of OH dissipation. Therefore, the predominant participation of OH in Sb(III) photooxidation was only possible on high-index {201} TiO2, which resulted in an enhanced photocatalytic rate. On the other hand, O2(-) dominated the Sb(III) photocatalytic oxidation on low-index TiO2. The intrinsic facet-dependent adsorption and photocatalytic mechanism obtained from this study would be useful for developing TiO2-based environmental technologies.

  2. 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.

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

    Directory of Open Access Journals (Sweden)

    Staffan Sandin

    2017-03-01

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

  4. Nitro-Grela-type complexes containing iodides – robust and selective catalysts for olefin metathesis under challenging conditions

    Directory of Open Access Journals (Sweden)

    Andrzej Tracz

    2015-10-01

    Full Text Available Iodide-containing nitro-Grela-type catalysts have been synthesized and applied to ring closing metathesis (RCM and cross metathesis (CM reactions. These new catalysts have exhibited improved efficiency in the transformation of sterically, non-demanding alkenes. Additional steric hindrance in the vicinity of ruthenium related to the presence of iodides ensures enhanced catalyst stability. The benefits are most apparent under challenging conditions, such as very low reaction concentrations, protic solvents or with the occurrence of impurities.

  5. Nitro-Grela-type complexes containing iodides – robust and selective catalysts for olefin metathesis under challenging conditions

    Science.gov (United States)

    Tracz, Andrzej; Matczak, Mateusz; Urbaniak, Katarzyna

    2015-01-01

    Summary Iodide-containing nitro-Grela-type catalysts have been synthesized and applied to ring closing metathesis (RCM) and cross metathesis (CM) reactions. These new catalysts have exhibited improved efficiency in the transformation of sterically, non-demanding alkenes. Additional steric hindrance in the vicinity of ruthenium related to the presence of iodides ensures enhanced catalyst stability. The benefits are most apparent under challenging conditions, such as very low reaction concentrations, protic solvents or with the occurrence of impurities. PMID:26664602

  6. Nitro-Grela-type complexes containing iodides - robust and selective catalysts for olefin metathesis under challenging conditions.

    Science.gov (United States)

    Tracz, Andrzej; Matczak, Mateusz; Urbaniak, Katarzyna; Skowerski, Krzysztof

    2015-01-01

    Iodide-containing nitro-Grela-type catalysts have been synthesized and applied to ring closing metathesis (RCM) and cross metathesis (CM) reactions. These new catalysts have exhibited improved efficiency in the transformation of sterically, non-demanding alkenes. Additional steric hindrance in the vicinity of ruthenium related to the presence of iodides ensures enhanced catalyst stability. The benefits are most apparent under challenging conditions, such as very low reaction concentrations, protic solvents or with the occurrence of impurities.

  7. Development and testing of a silver chloride-impregnated activated carbon for aqueous removal and sequestration of iodide.

    Science.gov (United States)

    Karanfil, T; Moro, E C; Serkiz, S M

    2005-11-01

    Silver impregnated activated carbon (SIAC) can effectively remove iodide from water and sequester it in the form of AgI(s)). Given the extremely insoluble nature of AgI(s), the spent SIAC can be safely disposed of in land burial facilities. However, when the molar ratio of silver to iodide is greater than one, which is typical for waters contaminated with iodide, unreacted silver on the SIAC leached into solution with decreasing pH. To minimize silver leaching, a silver chloride impregnated activated carbon (SIAC-Cl) was produced from a SIAC. Scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) and X-Ray Diffraction (XRD) analyses confirmed the presence of silver chloride on the SIAC-Cl. Batch isotherm experiments conducted at pH 5, 7 and 8 showed that the iodide uptakes of SIAC-Cl and SIAC were similar and independent of pH. SEM/EDX and XRD analyses after reaction with iodide indicated that chloride was exchanged with iodide to form AgI(s) on the SIAC-Cl. Batch leaching experiments demonstrated that leaching of silver from SIAC-Cl under acidic conditions was significantly lower than from SIAC. The performance of SIAC and SIAC-Cl for practical applications was evaluated by conducting column experiments using a radioactively contaminated groundwater that included 129I. SIAC and SIAC-Cl showed similar degrees of iodide uptake. However, a significant degree of silver leaching, about 50% of the total silver, occurred from the SIAC during the course of the column experiments, whereas silver leaching from SIAC-Cl was remarkably low (only 6% of the total silver). SIAC-Cl appears to be a suitable getter material to remove and sequester iodide from contaminated waste streams.

  8. Peroxide effects of iodide excess on mitochondria in Fischer rat thyroid cell line in the early period

    Institute of Scientific and Technical Information of China (English)

    李敏

    2014-01-01

    Objective To investigate the peroxide effects of iodide excess on mitochondria in Fischer rat thyroid cell line(FRTL)in the early period.Methods After treatment with 0.0 mmol/L(control group)or 0.1 mmol/L potassium iodide(KI)for 2,4 and 24 h,respectively,changes of mitochondrial superoxide formation were assayed by flow cytometry and fluorescence microscopy using mitochondria-targeted hydroethidine(Mito SOX).

  9. Effects of short-term potassium iodide treatment for thyrotoxicosis due to Graves disease in children and adolescents

    OpenAIRE

    Jeong, Kyung Uk; Lee, Hae Sang; Hwang, Jin Soon

    2014-01-01

    Purpose Graves disease is the most common cause of hyperthyroidism in children. Inorganic iodide has been used in combination with antithyroid drugs for more effective normalization of thyroid hormones in some cases of severe thyrotoxicosis. This study aimed to investigate clinical characteristics of childhood thyrotoxicosis and effectiveness of inorganic iodide in the early phase of treatment. Methods Sixty-seven pediatric patients (53 girls/14 boys, 11.1±3.4 years of age), with newly diagno...

  10. Study on Growth and Optical, Scintillation Properties of Thallium Doped Cesium Iodide –Scintillator Crystal

    Directory of Open Access Journals (Sweden)

    B. Ravi

    2014-06-01

    Full Text Available Single crystal of Thallium doped cesium Iodide –Scintillator crystal was grown using vertical Bridgeman technique. The grown crystal was included for cutting and polishing for the characterization purpose and this crystal was studied by optical transmission properties, photo luminescence and thermally luminescence characteristics. Gamma-ray detectors were fabricated using the grown crystal that showed good linearity and nearly 7.5% resolution at 662 keV.

  11. Rationale for the real-time and dynamic cell death assays using propidium iodide

    OpenAIRE

    Zhao, Hong; Oczos, Jadwiga; Janowski, Pawel; Trembecka, Dominika; Dobrucki, Jurek; Darzynkiewicz, Zbigniew; Wlodkowic, Donald

    2010-01-01

    We have recently reported an innovative approach to use charged fluorochromes such as propidium iodide (PI) in the real-time, dynamic cell viability assays. The present study was designed to provide a mechanistic rationale for the kinetic assays using cell permeability markers. Uptake of PI by live cells, effect on the cell cycle, long term proliferation capacity, DNA damage response and pharmacologic interactions with anticancer drugs were studied using both laser scanning microscopy and las...

  12. Studies on the Mechanisms of Methyl Iodide Adsorption and Iodine Retention on Silver-Mordenite

    Energy Technology Data Exchange (ETDEWEB)

    Nenoff, Tina Maria [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Soelberg, Nick [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-09-01

    Silver-containing mordenite (MOR) is a longstanding benchmark for radioiodine capture, reacting with molecular iodine (I2) to form AgI. However the mechanisms for organoiodine capture are not well understood. Here we investigate the capture of methyl iodide from complex mixed gas streams by combining chemical analysis of the effluent gas stream with in depth characterization of the recovered sorbent.

  13. Study on the Preparation and Characteristics of Cellulose/Silver Iodide Nanocomposite Film.

    Science.gov (United States)

    Lee, Yang Hun; Han, Sung Soo; Kang, Young Ah; Shin, Eun Joo

    2016-06-01

    In this study, the structure and properties of an organic-inorganic composite material prepared from cellulose doped with fine particles of silver iodide (AgI) were examined. The preparation of the composite involved the complexation of cellulose with polyiodide ions, such as I- and 13-, by immersion in iodine/potassium iodide (I2/KI: 0.2, 0.4, 0.6, 0.8, 1.0 M) or potassium iodide (KI: 0.6, 1.2, 1.8, 2.4, 3.0 M) aqueous solutions followed by reaction in a silver nitrate (AgNO3:1.0 M) aqueous solution. These procedures resulted in the in situ formation of fine β-AgI particles within the cellulose matrix. The characteristics and conductivities of prepared cellulose/silver iodide (AgI) nanocomposite films with different I2/KI and KI concentrations were investigated. AgI particle formation and aggregation increased on increasing I2/KI and KI concentrations as determined by SEM. X-ray results showed that KI could penetrate the cellulose crystal region and form AgI particles. The electrical conductivities of nanocomposite films treated with KI were higher than that of I2/KI at < 1.0 M of I2/KI and 3 M of KI, although the weight gain by AgI formation was lower than that of I2/KI. This was also attributed to the formation of smaller AgI particles and crystal defects. Highest electrical conductivity (3.8 x 10(-7) Ω(-1) cm(-1)) was obtained from the cellulose films (1.25 x 10(-11) Ω(-1) cm(-1)) treated with the aqueous solutions of 1.0 M I2/KI and 1.0 M AgNO3.

  14. Radiofrequency induction on sodium/iodide symporter expression of thyroid cancer

    Institute of Scientific and Technical Information of China (English)

    Youxin Tian; Qinjiang Liu; Yaqiong Ni

    2013-01-01

    Objective:The aim of this study was to investigate the ef ects of radiofrequency treatment on sodium/iodide symporter expression of thyroid cancer cells. Methods:In 29 thyroid cancer patients with low or no expression of soda\\iodide symporter, the radio frequency combined 131I therapy was used, the whole-body scintigraphy and serum Ig were detected before and after the radiofrequency treatment. Results:The whole-body scintigraphy showed that 4 cases (4/29) before radiofrequency treatment had positive iodine uptake, 19 cases (19/29) two weeks after radiofrequency treatment had the positive iodine uptake, 12 cases (12/29) four weeks after radiofrequency treatment had the positive iodine uptake. Four weeks after radiofrequency treatment, 5 cases had increased serum Ig levels, 17 cases had decreased serum Ig levels, 7 cases showed no change. 25 cases (25/29) were ef ective, 15 cases (15/29) were cured. Conclusion:The radiofrequency induced the non-expressed the sodium/iodide symporter of thyroid cancer cells regain the iodine intake ability, it improved the clinical ef icacy of 131I therapy in dedif erentiated thyroid cancer.

  15. Deteksi Natrium/Iodide Symporter (NIS pada Galur Sel Kanker Payudara SKBR3 dengan Imunositofluoresens

    Directory of Open Access Journals (Sweden)

    Aisyah Elliyanti

    2016-03-01

    Full Text Available SKBR-3 cell line is a breast cancer model for human epidermal growth factor receptor2 (HER2 positive. Only 50% of patients of this type have fully responded to chemotherapy. Natrium iodide symporter expression correlates with the uptake and ability of cells to accumulate radioiodine. The aim of this study was to examine natrium/iodide symporter (NIS expression and its distribution with and without epidermal growth factor (EGF treatment using immunocytofluoresence (ICF. This study was conducted at the Cell Culture Laboratory, Faculty of Medicine, Universitas Padjadjaran from September 2013 to April 2014. SKBR3 cells were cultured until 70% confluent. Cells were then divided into two groups: treatment group and control group. The treatment group was treated with EGF 50 ng/mL. Cells were incubated with primary antibody rabbit polyclonal antibody anti-NIS, and then were followed with secondary-antibody goat polyclonal antibody to rabbit. Data from the observation were then assessed semi-quantitatively. Natrium/iodide symporter was seen to be expressed and distributed in the cytoplasm. Cells induced by EGF showed significant increase in NIS expression in cytoplasm and its distribution in cell membrane. It is concluded that the SKBR3 cells express NIS in cytoplasm and that EGF induction increases NIS expression and distribution in cell membrane. This finding leads to a potential ability of breast cancer cells to uptake and accumulate radioiodine.

  16. Uptake of iodide by a mixture of metallic copper and cupric compounds

    Energy Technology Data Exchange (ETDEWEB)

    Lefevre, G.; Alnot, M.; Ehrhardt, J.J.; Bessiere, J. [Univ. Henri Poincare Nancy 1, Villers les Nancy (France). Lab. de Chimie Physique pour l`Environnement

    1999-05-15

    Environmental contaminants harmful to the health of present and future generations involve nuclear fission products as iodine radioisotopes. {sup 129}I is potentially one of the more mobile products because of its long half-life and its tendency to go into solution as an anion that is not retarded with silicate minerals. Ability of copper/cupric compound mixtures to remove iodide from solution was investigated to predict sorption of radioactive iodine in the environment and to assess their use in a nuclear reprocessing method. Thermodynamic calculations were performed to study the stability of such mixtures in solution and to obtain equilibrium constants of Cu(0)/Cu(II)/I{sup {minus}} and Cu(0)/Cu(II)/Cl{sup {minus}} systems. Both calculations and experimental results showed that a Cu(0)/Cu{sub 3}(OH){sub 2}(CO{sub 3}){sub 2} (azurite) mixture selectively uptakes iodide ions (initial concentrations: 10{sup {minus}2} and 10{sup {minus}1} M) in the presence of 10{sup {minus}1} M chloride ions. Reaction of iodide with copper powder and azurite crystal or copper plate and azurite powder have also been investigated, leading to precipitation of CuI onto massive copper phase. The different solids were separately analyzed by XPS and MEB-EDX, giving some insight in the uptake mechanism. It is proposed that soluble copper released by the cupric compound is reduced at the surface of metallic copper, leading to a preferential precipitation of CuI on copper surface.

  17. Use of potassium iodide in dermatology: updates on an old drug.

    Science.gov (United States)

    Costa, Rosane Orofino; Macedo, Priscila Marques de; Carvalhal, Aline; Bernardes-Engemann, Andréa Reis

    2013-01-01

    Potassium iodide, as a saturated solution, is a valuable drug in the dermatologist's therapeutic arsenal and is useful for the treatment of different diseases due to its immunomodulatory features. However, its prescription has become increasingly less frequent in dermatology practice. Little knowledge about its exact mechanism of action, lack of interest from the pharmaceutical industry, the advent of new drugs, and the toxicity caused by the use of high doses of the drug are some possible explanations for that. Consequently, there are few scientific studies on the pharmacological aspects, dosage and efficacy of this drug. Also, there is no conventional standard on how to manipulate and prescribe the saturated solution of potassium iodide, which leads to unawareness of the exact amount of the salt being delivered in grams to patients. Considering that dosage is directly related to toxicity and the immunomodulatory features of this drug, it is essential to define the amount to be prescribed and to reduce it to a minimum effective dose in order to minimize the risks of intolerance and thus improve treatment adherence. This review is relevant due to the fact that the saturated solution of potassium iodide is often the only therapeutic choice available for the treatment of some infectious, inflammatory and immune-mediated dermatoses, no matter whether the reason is specific indication, failure of a previous therapy or cost-effectiveness.

  18. Toxic impact of bromide and iodide on drinking water disinfected with chlorine or chloramines.

    Science.gov (United States)

    Yang, Yang; Komaki, Yukako; Kimura, Susana Y; Hu, Hong-Ying; Wagner, Elizabeth D; Mariñas, Benito J; Plewa, Michael J

    2014-10-21

    Disinfectants inactivate pathogens in source water; however, they also react with organic matter and bromide/iodide to form disinfection byproducts (DBPs). Although only a few DBP classes have been systematically analyzed for toxicity, iodinated and brominated DBPs tend to be the most toxic. The objectives of this research were (1) to determine if monochloramine (NH2Cl) disinfection generated drinking water with less toxicity than water disinfected with free chlorine (HOCl) and (2) to determine the impact of added bromide and iodide in conjunction with HOCl or NH2Cl disinfection on mammalian cell cytotoxicity and genomic DNA damage induction. Water disinfected with chlorine was less cytotoxic but more genotoxic than water disinfected with chloramine. For both disinfectants, the addition of Br(-) and I(-) increased cytotoxicity and genotoxicity with a greater response observed with NH2Cl disinfection. Both cytotoxicity and genotoxicity were highly correlated with TOBr and TOI. However, toxicity was weakly and inversely correlated with TOCl. Thus, the forcing agents for cytotoxicity and genotoxicity were the generation of brominated and iodinated DBPs rather than the formation of chlorinated DBPs. Disinfection practices need careful consideration especially when using source waters containing elevated bromide and iodide.

  19. Simple and rapid determination of iodide in table salt by stripping potentiometry at a carbon-paste electrode.

    Science.gov (United States)

    Svancara, Ivan; Ogorevc, Bozidar; Nović, Milko; Vytras, Karel

    2002-04-01

    A simple and rapid procedure, utilising constant-current stripping analysis (CCSA) at a carbon-paste electrode containing tricresyl phosphate as a pasting liquid (TCP-CPE), has been developed for the determination of iodide in table salt. Because of a synergistic accumulation mechanism based on ion-pairing and extraction of iodide in combination with electrolytic pretreatment of the TCP-CPE, the method is selective for iodide and enables direct determination of iodide in samples of table salt containing anti-caking agents such as K(4)[Fe(CN)(6)] (food additive "E 536") or MgO. The iodide content (calculated as KI) can be determined in a concentration range of 2 to 100 mg kg(-1) salt, with a detection limit (S/N=3) of 1 mg kg(-1), and a recovery from 90 to 115%. The proposed method has been used to determine iodide in several types of artificially iodised table salt and in one sample of natural sea salt. The results obtained agreed well with those obtained by use of three independent reference methods (titration, spectrophotometry, and ICP-MS) used to validate the CCSA method, indicating that the developed method is applicable as a routine procedure for rapid testing in salt production process control and in the analysis of marketed table salts.

  20. Activation of the Nrf2-Keap 1 Pathway in Short-Term Iodide Excess in Thyroid in Rats

    Directory of Open Access Journals (Sweden)

    Tingting Wang

    2017-01-01

    Full Text Available Wistar rats were randomly divided into groups of varying iodide intake: normal iodide; 10 times high iodide; and 100 times high iodide on Days 7, 14, and 28. Insignificant changes were observed in thyroid hormone levels (p>0.05. Urinary iodine concentration and iodine content in the thyroid glands increased after high consumption of iodide from NI to 100 HI (p<0.05. The urinary iodine concentration of the 100 HI group on Days 7, 14, and 28 was 60–80 times that of the NI group. The mitochondrial superoxide production and expressions of Nrf2, Srx, and Prx 3 all significantly increased, while Keap 1 significantly decreased in the 100 HI group when compared to the NI or 10 HI group on Days 7, 14, and 28 (p<0.05. Immunofluorescence staining results showed that Nrf2 was localized in the cytoplasm in NI group. Although Nrf2 was detected in both cytoplasm and nucleus in 10 HI and 100 HI groups, a stronger positive staining was found in the nucleus. We conclude that the activation of the Nrf2-Keap 1 antioxidative defense mechanism may play a crucial role in protecting thyroid function from short-term iodide excess in rats.

  1. Activation of the Nrf2-Keap 1 Pathway in Short-Term Iodide Excess in Thyroid in Rats

    Science.gov (United States)

    Liang, Xue

    2017-01-01

    Wistar rats were randomly divided into groups of varying iodide intake: normal iodide; 10 times high iodide; and 100 times high iodide on Days 7, 14, and 28. Insignificant changes were observed in thyroid hormone levels (p > 0.05). Urinary iodine concentration and iodine content in the thyroid glands increased after high consumption of iodide from NI to 100 HI (p Prx 3 all significantly increased, while Keap 1 significantly decreased in the 100 HI group when compared to the NI or 10 HI group on Days 7, 14, and 28 (p < 0.05). Immunofluorescence staining results showed that Nrf2 was localized in the cytoplasm in NI group. Although Nrf2 was detected in both cytoplasm and nucleus in 10 HI and 100 HI groups, a stronger positive staining was found in the nucleus. We conclude that the activation of the Nrf2-Keap 1 antioxidative defense mechanism may play a crucial role in protecting thyroid function from short-term iodide excess in rats. PMID:28133506

  2. 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.

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

    Science.gov (United States)

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

    2013-03-15

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

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

    Directory of Open Access Journals (Sweden)

    Raul R. Ribeiro

    2013-08-01

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

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

    Directory of Open Access Journals (Sweden)

    Magdalena Jabłońska-Czapla

    2015-01-01

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

  6. 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.

  7. 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.

  8. [The effect of long-term external ionizing radiation on the functional activity of rat thyroid under enhanced potassium iodide consumption].

    Science.gov (United States)

    Lupachik, S V; Nadol'nik, L I

    2008-01-01

    The study was devoted to the effect of long-term (20 days) external ionizing radiation at a dose of 0.5 Gy on the iodide metabolism in the rat thyroid under supplementation of high iodine doses (10 daily KI doses). It was found that the potassium iodide administration partially prevented the effects of a post radiation decrease of serum thyroid hormone levels (the level of T4 was normal and that of T3 was 77.4% of the controls). After the supplementation of 10 daily iodide doses, the rat thyroid tissue showed the most pronounced increase in the levels of total, free and protein-bound iodide compared to the groups of animals consuming normal and elevated KI doses. Pronounced inhibition of thyroid peroxidase activity (3.1-fold) was noted in the same group. The data obtained indicate a radiation-induced activation of iodide uptake during its enhanced supplementation and disturbed iodide enzymatic oxidation and organification.

  9. 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., Sb. With a 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.

  10. 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.

  11. 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

  12. 原子荧光法测透析用水中砷硒锑汞%Atomic fluorescence measuring dialysis water arsenic selenium antimony and mercury

    Institute of Scientific and Technical Information of China (English)

    骆胜超; 李皓

    2011-01-01

    目的:建立透析用水中砷、硒、锑、汞四种微量元素的原子荧光分析法.方法:水中砷和锑加还原剂后同时测定;硒经硝酸高氯酸氧化后,再经盐酸还原后测定;汞直接加硝酸使酸度为5%后测定.结果:汞的检出限为0.024μg/L;硒的检出限为0.044μg/L;砷的检出限为0.011 μg/L;锑的检出限为0.015μg/L.结论:本法用来测定透析用水中极其微量的砷、硒、锑、汞简便快速,且在双道原子荧光法仪中可同时进行砷和锑的检测.%Objective: To establish a method for detection of hemodialysis water arsenic, selenium,antimony and mercury.Methods: Arsenic and antimony in water were detectioned after added reductant, Selenium was detectioned by nitric acid and high chlorine acid oxidationed, Mercury was directly detectioned by adding acidity to 5%. Results:The detect limit for Mercury was 0.024 muon g/L, the detect limit for Selenium was 0. 044 muon g/L, Arsenic detect limit for 0.011 muon g/L, Antimony detect limit to. 015 muon g/L. Conclusion: This method wad simple and rapid for using to determine dialysis water in extremely trace of arsenic and selenium, antimony, mercury, and in double ways for atomic fluorescence analyzer can simultaneously arsenic and antimony detection

  13. [The analysis for silver iodide fine particles of TLC/FTIR matrix].

    Science.gov (United States)

    Zhu, Qing; Su, Xiao; Wu, Hai-Jun; Zhai, Yan-Jun; Xia, Jin-Ming; Buhebate; Xu, Yi-Zhuang; Wu, Jin-Guang

    2012-07-01

    In situ TLC/FTIR technique has tremendous potential in the analysis of complex mixtures. However, the progress in this technique was quite slow. The reason is that conventional stationary phase has strong absorption in FTIR spectrum and thus brings about severe interference in the detection of samples. To solve the problem, the authors propose to use AgI fine particles as stationary phase of TLC plate. The reasons are as follows: Silver iodide fine particles have no absorbance in an IR region between 4 000 and 800 cm(-1), therefore, the interference caused by IR absorption of stationary phase can be removed. Moreover, silver iodide is stable and insolvable in water and organic solvents and thus it will not be destroyed by mobile phase or react with samples during the TLC separation. To improve TLC separation efficiency and quality of FTIR spectra during the TLC/FTIR analysis, the size of AgI particles should be below 500 nm. We used orthogonal design approach to optimize the experimental condition to AgI particles so that the average size of AgI particles is around 100 nm. No absorption of impurity or adsorbed water were observed in FTIR spectrum of the AgI particles the authors used "settlement volatilization method" to prepare TLC plate without using polymeric adhesive that may bring about significant interference in FTIR analysis. Preliminary TLC experiments proved that the TLC plate using AgI fine particles as stationary phase can separate mixtures of rhodamine B and bromophenol blue successfully. Applications of silver iodide fine particles as stationary phase have bright perspective in the development of in-situ TLC/FTIR analysis techniques.

  14. Titrimetric and spectrophotometric assay of diethylcarbamazine citrate in formulations using iodate and iodide mixture as reagents

    Directory of Open Access Journals (Sweden)

    Nagaraju Swamy

    2015-03-01

    Full Text Available One titrimetric and two spectrophotometric methods are proposed for the determination of diethylcarbamazine citrate (DEC in bulk drug and in formulations using potassium iodate and potassium iodide as reagent. The methods employ the well-known analytical reaction between iodate and iodide in the presence of acid. In titrimetry (method A, the drug was treated with a measured excess of thiosulfate in the presence of unmeasured excess of iodate-iodide mixture and after a standing time of 10 min, the surplus thiosulfate was determined by back titration with iodine towards starch end point. Titrimetric assay is based on a 1:3 reaction stoichiometry between DEC and iodine and the method is applicable over 2.0-10.0 mg range. The liberated iodine is measured spectrophotometrically at 370 nm (method B or the iodine-starch complex measured at 570 nm (method C. In both methods, the absorbance is found to be linearly dependent on the concentration of iodine, which in turn is related to DEC concentration. The calibration curves are linear over 2.5-50 and 2.5-30 µg mL-1 DEC for method B and method C, respectively. The calculated molar absorptivity and Sandell sensitivity values were 6.48×103 L mol-1 cm-1 and 0.0604 µg cm-2, respectively, for method B, and their respective values for method C are 9.96×103 L mol-1 cm-1 and 0.0393 µg cm-2. The intra-day and inter-day accuracy and precision studies were carried out according to the ICH guidelines. The methods were successfully applied to the analysis of DEC formulations.

  15. Equations of state for crystalline zirconium iodide: The role of dispersion

    Energy Technology Data Exchange (ETDEWEB)

    Rossi, Matthew L., E-mail: mrossi@lanl.gov [Materials Science and Technology, MST-6, Los Alamos National Lab, Los Alamos, NM (United States); Taylor, Christopher D. [Materials Science and Technology, MST-6, Los Alamos National Lab, Los Alamos, NM (United States)

    2013-02-15

    We present the first-principle equations of state of several zirconium iodides, ZrI{sub 2}, ZrI{sub 3}, and ZrI{sub 4}, computed using density functional theory methods that apply various methods for introducing the dispersion correction. Iodides formed due to reaction of molecular or atomic iodine with zirconium and zircaloys are of particular interest due to their application to the cladding material used in the fabrication of nuclear fuel rods. Stress corrosion cracking (SCC), associated with fission product chemistry with the clad material, is a major concern in the life cycle of nuclear fuels, as many of the observed rod failures have occurred due to pellet–cladding chemical interactions (PCCI) [A. Atrens, G. Dannhäuser, G. Bäro, Stress-corrosion-cracking of zircaloy-4 cladding tubes, Journal of Nuclear Materials 126 (1984) 91–102; P. Rudling, R. Adamson, B. Cox, F. Garzarolli, A. Strasser, High burn-up fuel issues, Nuclear Engineering and Technology 40 (2008) 1–8]. A proper understanding of the physical properties of the corrosion products is, therefore, required for the development of a comprehensive SCC model. In this particular work, we emphasize that, while existing modeling techniques include methods to compute crystal structures and associated properties, it is important to capture intermolecular forces not traditionally included, such as van der Waals (dispersion) correction. Furthermore, crystal structures with stoichiometries favoring a high I:Zr ratio are found to be particularly sensitive, such that traditional density functional theory approaches that do not incorporate dispersion incorrectly predict significantly larger volumes of the lattice. This latter point is related to the diffuse nature of the iodide electron cloud.

  16. The sphingosine 1-phosphate receptor modulator FTY720 prevents iodide-induced autoimmune thyroiditis in non-obese diabetic mice.

    Science.gov (United States)

    Morohoshi, Kazuki; Osone, Michiko; Yoshida, Katsumi; Nakagawa, Yoshinori; Hoshikawa, Saeko; Ozaki, Hiroshi; Takahashi, Yurie; Ito, Sadayoshi; Mori, Kouki

    2011-09-01

    FTY720 is an immunomodulator that alters migration and homing of lymphocytes via sphingosine 1-phosphate receptors. This compound has been shown to be effective in suppressing autoimmune diseases in experimental and clinical settings. In the present study, we tested whether FTY720 prevented autoimmune thyroiditis in iodide-treated non-obese diabetic (NOD) mice, a model of Hashimoto's thyroiditis (HT) in humans. Mice were given 0.05% iodide water for 8 weeks, and this treatment effectively induced thyroiditis. Iodide-treated mice were injected intraperitoneally with either saline or FTY720 during the iodide treatment. FTY720 clearly suppressed the development of thyroiditis and reduced serum anti-thyroglobulin antibody levels. The number of circulating lymphocytes and spleen cells including CD4(+) T cells, CD8(+) T cells, and CD4(+)Foxp3(+) T cells was decreased in FTY720-treated mice. Our results indicate that FTY720 has immunomodulatory effects on iodide-induced autoimmune thyroiditis in NOD mice and may be a potential candidate for use in the prevention of HT.

  17. Crystal Growth and Dissolution of Methylammonium Lead Iodide Perovskite in Sequential Deposition: Correlation between Morphology Evolution and Photovoltaic Performance.

    Science.gov (United States)

    Hsieh, Tsung-Yu; Huang, Chi-Kai; Su, Tzu-Sen; Hong, Cheng-You; Wei, Tzu-Chien

    2017-03-01

    Crystal morphology and structure are important for improving the organic-inorganic lead halide perovskite semiconductor property in optoelectronic, electronic, and photovoltaic devices. In particular, crystal growth and dissolution are two major phenomena in determining the morphology of methylammonium lead iodide perovskite in the sequential deposition method for fabricating a perovskite solar cell. In this report, the effect of immersion time in the second step, i.e., methlyammonium iodide immersion in the morphological, structural, optical, and photovoltaic evolution, is extensively investigated. Supported by experimental evidence, a five-staged, time-dependent evolution of the morphology of methylammonium lead iodide perovskite crystals is established and is well connected to the photovoltaic performance. This result is beneficial for engineering optimal time for methylammonium iodide immersion and converging the solar cell performance in the sequential deposition route. Meanwhile, our result suggests that large, well-faceted methylammonium lead iodide perovskite single crystal may be incubated by solution process. This offers a low cost route for synthesizing perovskite single crystal.

  18. Electrical properties of solid iodo mercurates resulting from the reaction of HgI2 with alcaline iodides

    Science.gov (United States)

    Ponpon, J. P.; Amann, M.

    2005-01-01

    Potassium iodide solutions are currently used during the fabrication process of mercuric iodide based nuclear radiation detectors. However, KI treatment leaves the HgI2 surface covered with a residual compound (namely the potassium tri-iodo mercurate) which has a significant influence on the surface properties and stability of mercuric iodide devices and therefore on the detectors characteristics. Looking for other solutions to etch mercuric iodide, we found it interesting to investigate the electrical properties of the compounds which may form when etching HgI2 in NH4I, NaI, and RbI. For this purpose, solid iodo mercurates with the cations ammonium, sodium, and rubidium, have been prepared by reacting HgI2 with the solutions of interest. Study of the electrical properties of these samples and comparison with those of potassium tri-iodo mercurate ones, especially with respect to humidity, indicates noticeable stability differences in presence of water vapour. This could have interesting consequences on the surface cleaning of mercuric iodide.

  19. A novel vortex-assisted liquid-liquid microextraction approach using auxiliary solvent: Determination of iodide in mineral water samples.

    Science.gov (United States)

    Zaruba, Serhii; Vishnikin, Andriy B; Andruch, Vasil

    2016-01-01

    A novel vortex-assisted liquid-liquid microextraction (VA-LLME) for determination of iodide was developed. The method includes the oxidation of iodide with iodate in the presence of hydrochloric acid followed by VA-LLME of the ion-pair formed between ICl2(-) and Astra Phloxine reagent (AP) and subsequent absorbance measurement at 555nm. The appropriate experimental conditions were investigated and found to be: 5mL of sample, 0.27molL(-)(1) HCl, 0.027mmolL(-1) KIO3 as the oxidation agent, 250μL of extraction mixture containing amyl acetate as the extraction solvent and carbon tetrachloride as the auxiliary solvent (1:1, v/v), 0.04mmolL(-1) AP reagent, vortex time: 20s at 3000rpm, centrifugation: 4min at 3000rpm. The calibration plot was linear in the range 16.9-169μg L(-1) of iodide, with a correlation coefficient (R(2)) of 0.996, and the relative standard deviation ranged from 1.9 to 5.7%. The limit of detection (LOD) and limit of quantification (LOQ) were 1.75 and 6.01μgL(-)(1) of iodide, respectively. The suggested procedure was applied for determination of iodide in real mineral water samples.

  20. An iodine supplementation of tomato fruits coated with an edible film of the iodide-doped chitosan.

    Science.gov (United States)

    Limchoowong, Nunticha; Sricharoen, Phitchan; Techawongstien, Suchila; Chanthai, Saksit

    2016-06-01

    In general, the risk of numerous thyroid cancers inevitably increases among people with iodine deficiencies. An iodide-doped chitosan (CT-I) solution was prepared for dipping tomatoes to coat the fresh surface with an edible film (1.5 μm), thereby providing iodine-rich fruits for daily intake. Characterisation of the thin film was conducted by FTIR and SEM. Stability of the CT-I film was studied via water immersion at various time intervals, and no residual iodide leached out due to intrinsic interactions between the cationic amino group of chitosan and iodide ions. Moreover, the iodide supplement exhibited no effect on the antioxidant activity of tomatoes. The iodine content in the film-coated tomato was determined by ICP-OES. The tomato coating with 1.5% (w/v) CT-I contained approximately 0.4 μg iodide per gram fresh weight. In addition, the freshness and storability of iodine-doped tomatoes were also maintained for shelf-life concerns.

  1. Towards Renewable Iodide Sources for Electrolytes in Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Iryna Sagaidak

    2016-03-01

    Full Text Available A novel family of iodide salts and ionic liquids based on different carbohydrate core units is herein described for application in dye-sensitized solar cell (DSC. The influence of the molecular skeleton and the cationic structure on the electrolyte properties, device performance and on interfacial charge transfer has been investigated. In combination with the C106 polypyridyl ruthenium sensitizer, power conversion efficiencies lying between 5.0% and 7.3% under standard Air Mass (A.M. 1.5G conditions were obtained in association with a low volatile methoxypropionitrile (MPN-based electrolyte.

  2. Performance of neutron activation analysis in the evaluation of bismuth iodide purification methodology

    Energy Technology Data Exchange (ETDEWEB)

    Armelin, Maria Jose A.; Ferraz, Caue de Mello; Hamada, Margarida M., E-mail: marmelin@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Lab. de Analise por Ativacao Neutronica

    2015-07-01

    Bismuth tri-iodide (BrI{sub 3}) is an attractive material for using as a semiconductor. In this paper, BiI{sub 3} crystals have been grown by the vertical Bridgman technique using commercially available powder. The impurities were evaluated by instrumental neutron activation analysis (INAA). The results show that INAA is an analytical method appropriate for monitoring the impurities of: Ag, As, Br, Cr, K, Mo, Na and Sb in the various stages of the BiI{sub 3} purification methodology. (author)

  3. Introduction to fifth international workshop on mercuric iodide nuclear radiation detectors

    Energy Technology Data Exchange (ETDEWEB)

    Schieber, M.

    1982-01-01

    Mercuric iodide is a wide bandgap semiconductor, with Eg approx. = 2.14 eV at room temperature. Therefore, HgI/sub 2/ is totally different from the well-studied, narrower gap, elemental semiconductors such as Si and Ge, and also different in its physical and chemical properties from the known semiconductor binary zinc-blend compounds such as GaAs or InP. The purpose of studies in the last decade was to further our understanding of HgI/sub 2/; recent progress is reported. (WHK)

  4. Effects of Aromatic Ammoniums on Methyl Ammonium Lead Iodide Hybrid Perovskite Materials

    Directory of Open Access Journals (Sweden)

    Jianli Yang

    2017-01-01

    Full Text Available The introduction of bulky ammoniums into methyl ammonium lead iodide hybrid perovskites (MAPbI3 has emerged as a promising strategy to improve the properties of these materials. In the present work, we studied the effects of several aromatic ammoniums onto the structural, electronic, and optical properties of MAPbI3. Although powder XRD data suggest that the bulky cations are not involved in the bulk phase of the MAPbI3, a surprisingly large effect of the bulky cations onto the photoluminescence properties was observed.

  5. Nucleophilic addition to the ethynyl group in ethynylestradiol catalyzed by crown ether-copper (1) iodide.

    Science.gov (United States)

    Chen, S H; Luo, G R; Chang, X Z; Zhao, H M

    1991-10-01

    A new and convenient synthetic route to acetylation of estrogens is described. Benzo-15-crown-5 and cuprous iodide-mixed catalyst catalyzed the nucleophilic addition of 2,4-dibromoethynylestradiol, resulting in the formation of a new compound, 2,4-dibromo-17 alpha-acetylestradiol, of which the structure was characterized by infrared, UV, 1H nuclear magnetic resonance, mass spectra, and elemental analysis. It was found that the yield of this approach is much higher than that obtained in the hydration of usual acetylenic compounds.

  6. Subcutaneous Zygomycosis: A Report of One Case Responding Excellently to Potassium Iodide.

    Science.gov (United States)

    Mondal, Ashim Kr; Saha, Abhijit; Seth, Joly; Mukherjee, Soumya

    2015-01-01

    Subcutaneous Zygomycosis is a rare opportunistic fungal infection caused by Basidiobolus ranarum. Though this entity is endemic in South India, limited numbers of cases have been reported from this part of the country. We report a case of subcutaneous zygomycosis in a 25 year old lady who presented with a nontender, firm to hard swelling over the upper-left arm. Finger was easily inserted below the indurated edge. Histopathology revealed suppurative granuloma with aseptate hyphae. Patient responded excellently to saturated solution of potassium iodide in subsequent visits.

  7. Spectroscopy of stop bands in artificial opals filled with an alcohol solution of potassium iodide

    Science.gov (United States)

    Gorelik, V. S.; Filatov, V. V.

    2012-09-01

    The spectral position of the stop bands in photonic crystals based on artificial opals filled with an alcohol solution of potassium iodide is investigated. The energy-band structure of samples with quartz globules 230 nm in diameter is modeled based on the dispersion equation. The spectral position of the stop bands in the [111] direction at different solution concentrations is determined. The conditions for forbidden-band "collapse" are established. The possibility of applying artificial opals in optical cavities of lasers of different types is analyzed.

  8. Subcutaneous zygomycosis: A report of one case responding excellently to potassium iodide

    Directory of Open Access Journals (Sweden)

    Ashim Kr Mondal

    2015-01-01

    Full Text Available Subcutaneous Zygomycosis is a rare opportunistic fungal infection caused by Basidiobolus ranarum. Though this entity is endemic in South India, limited numbers of cases have been reported from this part of the country. We report a case of subcutaneous zygomycosis in a 25 year old lady who presented with a nontender, firm to hard swelling over the upper-left arm. Finger was easily inserted below the indurated edge. Histopathology revealed suppurative granuloma with aseptate hyphae. Patient responded excellently to saturated solution of potassium iodide in subsequent visits.

  9. Atypical Cutaneous Sporotrichosis in an Immunocompetent Adult: Response to Potassium Iodide.

    Science.gov (United States)

    Gandhi, Nikita; Chander, Ram; Jain, Arpita; Sanke, Sarita; Garg, Taru

    2016-01-01

    Cutaneous sporotrichosis, also known as "Rose Gardener's disease," caused by dimorphic fungus Sporothrix schenkii, is usually characterized by indolent nodular or nodulo-ulcerative lesions arranged in a linear pattern. We report bizarre nonlinear presentation of Sporotrichosis, in an immunocompetent adult occurring after a visit to Amazon rain forest, speculating infection with more virulent species of Sporothrix. The diagnosis was reached with the help of periodic acid-Schiff positive yeast cells and cigar shaped bodies seen in skin biopsy along with the therapeutic response to potassium iodide.

  10. Successful Therapy of Refractory Erythema Nodosum Associated with Crohn's Disease Using Potassium Iodide

    Directory of Open Access Journals (Sweden)

    John K Marshall

    1997-01-01

    Full Text Available Erythema nodosum is a common extraintestinal manifestation of Crohn's disease. While mild skin involvement often responds to conservative management, severe or refractory cases may require systemic corticosteroid or immunosuppressive therapy. This report describes successful treatment of severe, refractory erythema nodosum associated with Crohn's colitis using oral potassium iodide. While the mechanism of action of this agent is poorly understood, it appears to be an effective and nontoxic therapy for Crohn's-related erythema nodosum and warrants further evaluation in a placebo controlled trial.

  11. Growth and characterization of NLO crystal: L-leucine phthalic acid potassium iodide

    OpenAIRE

    Jagadeesh M.R.; Kumar H .M. Suresh; Kumari R. Ananda

    2015-01-01

    A new semi-organic non linear optical crystal, L-leucine phthalic acid potassium iodide (LLPPI) has been grown from an aqueous solution by slow evaporation method. The grown crystals were subjected to different characterizations, such as single crystal XRD, FT-IR, UV-Vis, TGA, SEM, EDAX, micro hardness, dielectric and powder SHG. Single crystal structure was determined from X-ray diffraction data and it revealed that the crystal belongs to triclinic system with the space group P1. The vibrati...

  12. Real-Time Observation of Organic Cation Reorientation in Methylammonium Lead Iodide Perovskites

    OpenAIRE

    2015-01-01

    This document is the Accepted Manuscript version of a Published Work that appeared in final form in The Journal of Physical Chemistry Letters, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://pubs.acs.org/doi/abs/10.1021/acs.jpclett.5b01555 The introduction of a mobile and polarized organic moiety as a cation in 3D lead-iodide perovskites brings fascinating optoelectronic properties to t...

  13. Atypical cutaneous sporotrichosis in an immunocompetent adult: Response to potassium iodide

    Directory of Open Access Journals (Sweden)

    Nikita Gandhi

    2016-01-01

    Full Text Available Cutaneous sporotrichosis, also known as “Rose Gardener's disease,” caused by dimorphic fungus Sporothrix schenkii, is usually characterized by indolent nodular or nodulo-ulcerative lesions arranged in a linear pattern. We report bizarre nonlinear presentation of Sporotrichosis, in an immunocompetent adult occurring after a visit to Amazon rain forest, speculating infection with more virulent species of Sporothrix. The diagnosis was reached with the help of periodic acid-Schiff positive yeast cells and cigar shaped bodies seen in skin biopsy along with the therapeutic response to potassium iodide.

  14. Zinc iodide-osmium staining of membrane-coating granules in keratinized and non-keratinized mammalian oral epithelium.

    Science.gov (United States)

    Squier, C A

    1982-01-01

    Specimens of keratinized and non-keratinized oral epithelium were examined in the electron microscope after being stained with zinc iodide-osmium. In both types of tissue, reaction was seen in unmyelinated nerves, in the specific granules of epithelial Langerhans cells and within lysosome-like organelles and small vesicles associated with Golgi systems. In keratinized epithelia, the reaction was also present in the membrane-coating granules and between the deepest cells of the keratinized layer. In contrast, the membrane-coating granules of non-keratinized epithelia lacked Zn iodide-osmium staining despite the presence of reaction in adjacent Golgi systems. It is suggested that Zn iodide-osmium stains glycolipid or glycoprotein material in the cell. This material is elaborated in the Golgi systems from which lysosomes and the membrane-coating granules of keratinized tissues are probably derived.

  15. Colorimetric Solid Phase Extraction for the Measurement of Total I (Iodine, Iodide, and Triiodide) in Spacecraft Drinking Water

    Science.gov (United States)

    Lipert, Robert J.; Porter, Marc D.; Siperko, Lorraine M.; Gazda, Daniel B.; Rutz, Jeff A.; Schultz, John R.; Carrizales, Stephanie M.; McCoy, J. Torin

    2009-01-01

    An experimental drinking water monitoring kit for the measurement of iodine and silver(I) was recently delivered to the International Space Station (ISS). The kit is based on Colorimetric Solid Phase Extraction (CSPE) technology, which measures the change in diffuse reflectance of indicator disks following exposure to a water sample. To satisfy additional spacecraft water monitoring requirements, CSPE has now been extended to encompass the measurement of total I (iodine, iodide, and triiodide) through the introduction of an oxidizing agent, which converts iodide and triiodide to iodine, for measurement using the same indicator disks currently being tested on ISS. These disks detect iodine, but are insensitive to iodide and triiodide. We report here the operational considerations, design, and ground-based performance of the CSPE method for total I. The results demonstrate that CSPE technology is poised to meet NASA's total I monitoring requirements.

  16. Bio-inspired stabilization of sulfenyl iodide RS-I in a Zr(IV)-based metal-organic framework.

    Science.gov (United States)

    Yee, Ka-Kit; Wong, Yan-Lung; Xu, Zhengtao

    2016-03-28

    A Zr(IV)-based metal-organic framework (MOF) appended with free-standing thiol (-SH) groups was found to react readily with I2 molecules to form sulfenyl iodide (S-I) units. In contrast to its solution chemistry of facile disproportionation into disulfide and I2, the sulfenyl iodide (SI) function, anchored onto the rigid MOF grid and thus prevented from approaching one another to undergo the dismutation reaction, exhibits distinct stability even at elevated temperatures (e.g., 90 °C). On a conceptual plane, this simple and effective solid host also captures the spatial confinement observed for the complex biomacromolecular scaffolds involved in iodine thyroid chemistry, wherein the spatial isolation and consequent stabilization of sulfenyl/selenenyl iodides are exerted by means of the protein scaffolds.

  17. Synthesis of 1-/sup 11/C-labelled ethyl, propyl, butyl and isobutyl iodides and examples of alkylation reactions

    Energy Technology Data Exchange (ETDEWEB)

    Laangstroem, B.; Antoni, G.; Gullberg, P.; Halldin, C.; Naagren, K.; Rimland, A.; Svaerd, H.

    1986-01-01

    New /sup 11/C-labelled precursors (1-/sup 11/C)ethyl,(1-/sup 11/C)propyl, (1-/sup 11/C)butyl, and (1-/sup 11/C)isobutyl iodides have been prepared by a 3-step reaction route using a one-pot system. The labelled iodides were obtained in 20-55% radiochemical yields and 65-95% radiochemical purities, with a total time for synthesis of the order of 10-14 min. The labelled iodides have been used in alkylation reactions with nitrogen, oxygen and carbon nucleophiles. The nitrogen alkylation reactions are exemplified by the synthesis of the analgetics N-(1-/sup 11/C-ethyl)iodocaine and N-(1-/sup 11/C-butyl) bupivacaine. The synthesis of 3-nitrophenyl(1-/sup 11/C)propyl ether is also presented in this paper as an example of an oxygen alkylation.

  18. Heat capacity and density of potassium iodide solutions in mixed N-methylpyrrolidone-water solvent at 298.15 K

    Science.gov (United States)

    Novikov, A. N.

    2014-10-01

    The heat capacity and density of potassium iodide solutions in a mixed N-methylpyrrolidone (MP)-water solvent with a low content of the organic component are measured via calorimetry and densimetry at 298.15 K. Standard partial molal heat capacities and volumes of potassium iodide in MP-water mixtures are calculated. Standard heat capacities and volumes of potassium and iodide ions are determined. The character of the changes in heat capacity and volume are discussed on the basis of calculating additivity coefficients δ c and δ v upon the mixing of isomolal binary solutions KI-MP and KI-water, depending on the composition of the MP-H2O mixture and the concentration of the electrolyte.

  19. Phase diagram of an iodine-potassium iodide-water-ethanol system at 25°C

    Science.gov (United States)

    Varlamova, T. M.; Rubtsova, E. M.; Mushtakova, S. P.

    2012-09-01

    Phase equilibriums are studied in the isothermal-isobaric sections of the phase diagram of a fourcomponent iodine-potassium iodide-water-ethanol system at 25°C and atmospheric pressure. The compositions of the solvent at which it exhibits the greatest ability to dissolve iodine are established. It is shown that in all the investigated sections, there is three-phase eutonic equilibrium with potassium iodide and crystalline iodine as the solid phases. It is revealed that in the sections containing 30 and 50% of ethanol, potassium iodide serves as the salting in agent for crystalline iodine, due to the formation of polyiodide complexes of various composition in the studied system.

  20. Alterations in Evoked Otoacoustic Emissions by the Use of Meglumine Antimoniate in American Tegumentary Leishmaniasis Patients

    Science.gov (United States)

    de Oliveira Bezerra, Débora Cristina; Oliveira de Barcelos, Renata; Carvalho de Castro, Ellen; Jardim Duarte, Claudia Cristina; de Vasconcellos Carvalhaes Oliveira, Raquel; Salgado de Sousa Torraca, Tania; de Araújo-Melo, Maria Helena; Pereira Bom Braga, Frederico; Ramos Ferreira Terceiro, Benivaldo; do Nascimento Brahim Paes, Lúcia Regina; de Oliveira Schubach, Armando

    2017-01-01

    Introduction Tegumentary Leishmaniasis (TL) is a neglected, non-contagious, infectious disease, caused by different protozoa species of the Leishmania genus that affects skin and mucous membranes. Meglumine Antimoniate (MA), the first drug of choice for TL treatment in Brazil, has already been associated with cochlear toxicity, which is defined as damages of the cochlea caused by exposure to chemical substances, resulting in reversible or irreversible hearing loss. Auditory monitoring for cochlear toxicity aims at the early detection of auditory disorders, enabling, when possible, hearing to be preserved or an early auditory rehabilitation. Although otoacoustic emissions (OAEs) are used in this monitoring, there is no consensus on the criteria that define cochlear toxicity by this examination. The objective of this study was to describe the characteristics of the OAEs in cochlear toxicity monitoring in TL patients using MA. Methods Prospective and longitudinal study of auditory monitoring of 35 patients with parasitological diagnosis of TL, with liminal tonal audiometry, high frequency audiometry, immitanciometry, distortion product evoked otoacoustic emissions (DPEOAEs) and transient evoked otoacoustic emissions (TEOAEs) before treatment, at the end of treatment, one month after the end of treatment and two months after the end of treatment. Results 80% male, with median age of 44 years (IIQ: 22–59). In the pre-treatment evaluation: 11.4% complained of hearing loss and 20% of tinnitus, 48.6% presented auditory alterations in liminal tonal audiometry (LTA, 65.2% in high frequency audiometry (HFA), 26.6% in DPEOAE and 51.4% in TEOAE. No association was verified between genre and alterations in the EOAE examinations. We observed that patients that presented disorders in DPEOAE examinations were 17 years older than those without alterations and that patients that showed disorders in TEOAEO examinations were 34 years older than those without disorders. The presence

  1. Source Identification Of Airborne Antimony On The Basis Of The Field Monitoring And The Source Profiling

    Science.gov (United States)

    Iijima, A.; Sato, K.; Fujitani, Y.; Fujimori, E.; Tanabe, K.; Ohara, T.; Shimoda, M.; Kozawa, K.; Furuta, N.

    2008-12-01

    The results of the long-term monitoring of airborne particulate matter (APM) in Tokyo indicated that APM have been extremely enriched with antimony (Sb) compared to crustal composition. This observation suggests that the airborne Sb is distinctly derived from human activities. According to the material flow analysis, automotive brake abrasion dust and fly ash from waste incinerator were suspected as the significant Sb sources. To clarify the emission sources of the airborne Sb, elemental composition, particle size distribution, and morphological profiles of dust particles collected from two possible emission sources were characterized and compared to the field observation data. Brake abrasion dust samples were generated by using a brake dynamometer. During the abrasion test, particle size distribution was measured by an aerodynamic particle sizer spectrometer. Concurrently, size- classified dust particles were collected by an Andersen type air sampler. Fly ash samples were collected from several municipal waste incinerators, and the bulk ash samples were re-dispersed into an enclosed chamber. The measurement of particle size distribution and the collection of size-classified ash particles were conducted by the same methodologies as described previously. Field observations of APM were performed at a roadside site and a residential site by using an Andersen type air sampler. Chemical analyses of metallic elements were performed by an inductively coupled plasma atomic emission spectrometry and an inductively coupled plasma mass spectrometr. Morphological profiling of the individual particle was conducted by a scanning electron microscope equipped with an energy dispersive X-ray spectrometer. High concentration of Sb was detected from both of two possible sources. Particularly, Sb concentrations in a brake abrasion dust were extremely high compared to that in an ambient APM, suggesting that airborne Sb observed at the roadside might have been largely derived from

  2. Depression of alveolar macrophage hydrogen peroxide and superoxide anion release by mineral dusts: correlation with antimony, lead, and arsenic contents.

    Science.gov (United States)

    Gulyas, H; Labedzka, M; Gercken, G

    1990-04-01

    Activated rabbit alveolar macrophages were incubated with airborne dusts from four West German sites (1 to 200 micrograms/10(6) cells) and waste incinerator fly ash fractions (50 to 500 micrograms/10(6) cells). Quartz dust DQ 12 (5 to 200 micrograms/10(6) cells) and Fe2O3 (0.05 to 50 micrograms/10(6) cells) were used as control dusts. The zymosan-stimulated hydrogen peroxide and superoxide anion release of the macrophages were not affected significantly by Fe2O3. All other investigated dusts decreased the two cell functions which were correlated negatively with surfaces, particle numbers, and antimony, lead, and arsenic contents of the dusts. The influence of heavy metal antagonisms and dust surfaces on dust toxicity against alveolar macrophages is discussed.

  3. 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.

  4. Comparative proteomics study on meglumine antimoniate sensitive and resistant Leishmania tropica isolated from Iranian anthroponotic cutaneous leishmaniasis patients.

    Science.gov (United States)

    Hajjaran, H; Azarian, B; Mohebali, M; Hadighi, R; Assareh, A; Vaziri, B

    2012-02-01

    In order to define the protein expressional changes related to the process of meglumine antimoniate resistance in anthroponotic cutaneous leishmaniasis (CL), we performed a comparative proteomics analysis on sensitive and resistant strains of Leishmania tropica isolated from Iranian CL patients. Cell proteins were analysed with 2-dimensional electrophoresis and differentially expressed proteins were identified by matrix-assisted laser desorption/ ionization time-of-flight mass spectrometry. Image analysis of the matched maps identified 7 proteins that were either over- or down-expressed: activated protein kinase c receptor(LACK), alpha tubulin (x2), prostaglandin f2-alpha synthase, protein disulfide isomerase, vesicular transport protein and a hypothetical protein. The study shows the usefulness of proteomics in identifying proteins that may express differences between sensitive and resistant L. tropica isolates.

  5. Antimony-doped tin oxide nanorods as a transparent conducting electrode for enhancing photoelectrochemical oxidation of water by hematite.

    Science.gov (United States)

    Sun, Yiqing; Chemelewski, William D; Berglund, Sean P; Li, Chun; He, Huichao; Shi, Gaoquan; Mullins, C Buddie

    2014-04-23

    We report the growth of well-defined antimony-doped tin oxide (ATO) nanorods as a conductive scaffold to improve hematite's photoelectrochemical water oxidation performance. The hematite grown on ATO exhibits greatly improved performance for photoelectrochemical water oxidation compared to hematite grown on flat fluorine-doped tin oxide (FTO). The optimized photocurrent density of hematite on ATO is 0.67 mA/cm(2) (0.6 V vs Ag/AgCl), which is much larger than the photocurrent density of hematite on flat FTO (0.03 mA/cm(2)). Using H2O2 as a hole scavenger, it is shown that the ATO nanorods indeed act as a useful scaffold and enhanced the bulk charge separation efficiency of hematite from 2.5% to 18% at 0.4 V vs Ag/AgCl.

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

    Directory of Open Access Journals (Sweden)

    Gagandeep Kaur

    2014-01-01

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

  7. Removal of antimony (Sb(V)) from Sb mine drainage: biological sulfate reduction and sulfide oxidation-precipitation.

    Science.gov (United States)

    Wang, Huawei; Chen, Fulong; Mu, Shuyong; Zhang, Daoyong; Pan, Xiangliang; Lee, Duu-Jong; Chang, Jo-Shu

    2013-10-01

    Antimony (Sb(V)) in Sb mine drainage has adverse effects on the receiving water environments. This study for the first time demonstrated the feasibility of using sulfate-reducing bacteria (SRB) to convert sulfate ions in SMD into sulfides that reduce Sb(V) to Sb(III) and to form complex with Sb(III) as precipitate. The principal compound in the precipitate was stibnite (Sb2S3) at pH 7 and pH 9. The Sb(V) removal mechanism is sulfate-reduction and sulfide oxidization-precipitation, different from the conventional SRB-precipitation processes for heavy metals. The Sb(V)/sulfate ratio is noted an essential parameter affecting the Sb removal efficiency from SMD.

  8. Premature capacity loss in lead/acid batteries: a discussion of the antimony-free effect and related phenomena

    Science.gov (United States)

    Hollenkamp, A. F.

    Instances of severe capacity loss in apparently healthy lead/acid batteries have been reported over a period of many years, and are still common today. In most cases, these phenomena are linked to the use of antimony-free positive grids and are invoked by repetitive deep-discharge duties. This situation represents probably the greatest barrier to the expansion of markets for lead/acid batteries. To date, research has focused on several possible explanations for capacity loss; notably, degradation of the positive active mass (e.g., relaxable insufficient mass utilization) and the development of electrical barriers around the grid. Although much of the evidence gathered is circumstantial, it does point to the key issues that must be addressed in future work.

  9. 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.

  10. 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

  11. 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

  12. Analysis of heterogeneous water vapor uptake by metal iodide cluster ions via differential mobility analysis-mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Oberreit, Derek [Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455 (United States); Fluid Measurement Technologies, Inc., Saint Paul, Minnesota 55110 (United States); Rawat, Vivek K.; Larriba-Andaluz, Carlos; Ouyang, Hui; McMurry, Peter H.; Hogan, Christopher J., E-mail: hogan108@umn.edu [Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2015-09-14

    The sorption of vapor molecules onto pre-existing nanometer sized clusters is of importance in understanding particle formation and growth in gas phase environments and devising gas phase separation schemes. Here, we apply a differential mobility analyzer-mass spectrometer based approach to observe directly the sorption of vapor molecules onto iodide cluster ions of the form (MI){sub x}M{sup +} (x = 1-13, M = Na, K, Rb, or Cs) in air at 300 K and with water saturation ratios in the 0.01-0.64 range. The extent of vapor sorption is quantified in measurements by the shift in collision cross section (CCS) for each ion. We find that CCS measurements are sensitive enough to detect the transient binding of several vapor molecules to clusters, which shift CCSs by only several percent. At the same time, for the highest saturation ratios examined, we observed CCS shifts of up to 45%. For x < 4, cesium, rubidium, and potassium iodide cluster ions are found to uptake water to a similar extent, while sodium iodide clusters uptake less water. For x ≥ 4, sodium iodide cluster ions uptake proportionally more water vapor than rubidium and potassium iodide cluster ions, while cesium iodide ions exhibit less uptake. Measured CCS shifts are compared to predictions based upon a Kelvin-Thomson-Raoult (KTR) model as well as a Langmuir adsorption model. We find that the Langmuir adsorption model can be fit well to measurements. Meanwhile, KTR predictions deviate from measurements, which suggests that the earliest stages of vapor uptake by nanometer scale species are not well described by the KTR model.

  13. Analysis of perchlorate, thiocyanate, nitrate and iodide in human amniotic fluid using ion chromatography and electrospray tandem mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Blount, Benjamin C. [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA 30341 (United States)]. E-mail: bblount@cdc.gov; Valentin-Blasini, Liza [Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA 30341 (United States)

    2006-05-10

    Because of health concerns surrounding in utero exposure to perchlorate, we developed a sensitive and selective method for quantifying iodide, as well as perchlorate and other sodium-iodide symporter (NIS) inhibitors in human amniotic fluid using ion chromatography coupled with electrospray ionization tandem mass spectrometry. Iodide and NIS inhibitors were quantified using a stable isotope-labeled internal standards (Cl{sup 18}O{sub 4} {sup -}, S{sup 13}CN{sup -} and {sup 15}NO{sub 3} {sup -} with excellent assay accuracy of 100%, 98%, 99%, 95% for perchlorate, thiocyanate, nitrate and iodide, respectively, in triplicate analysis of spiked amniotic fluid sample). Excellent analytical precision (<5.2% RSD for all analytes) was found when amniotic fluid quality control pools were repetitively analyzed for iodide and NIS-inhibitors. Selective chromatography and tandem mass spectrometry reduced the need for sample cleanup, resulting in a rugged and rapid method capable of routinely analyzing 75 samples/day. Analytical response was linear across the physiologically relevant concentration range for the analytes. Analysis of a set of 48 amniotic fluid samples identified the range and median levels for perchlorate (0.057-0.71, 0.18 {mu}g/L), thiocyanate (<10-5860, 89 {mu}g/L), nitrate (650-8900, 1620 {mu}g/L) and iodide (1.7-170, 8.1 {mu}g/L). This selective, sensitive, and rapid method will help assess exposure of the developing fetus to low levels of NIS-inhibitors and their potential to inhibit thyroid function.

  14. Formation of organic iodine supplied as iodide in a soil-water system in Chiba, Japan.

    Science.gov (United States)

    Shimamoto, Yoko S; Takahashi, Yoshio; Terada, Yasuko

    2011-03-15

    Speciation of iodine in a soil-water system was investigated to understand the mechanism of iodine mobility in surface environments. Iodine speciation in soil and pore water was determined by K-edge XANES and HPLC-ICP-MS, respectively, for samples collected at a depth of 0-12 cm in the Yoro area, Chiba, Japan. Pore water collected at a 0-6 cm depth contained 50%-60% of organic iodine bound to dissolved organic matter, with the other portion being I(-). At a 9-12 cm depth, 98% of iodine was in the form of dissolved I(-). In contrast, XANES analysis revealed that iodine in soil exists as organic iodine at all depths. Iodine mapping of soil grains was obtained using micro-XRF analysis, which also indicated that iodine is bound to organic matter. The activity of laccase, which has the ability to oxidize I(-) to I(2), was high at the surface of the soil-water layer, suggesting that iodide oxidizing enzymes can promote iodine organification. The distribution coefficient of organic iodine in the soil-water system was more than 10-fold greater than that of iodide. Transformation of inorganic iodine to organic iodine plays an important role in iodine immobilization, especially in a surface soil-water system.

  15. Photocatalytic hydrogen generation from hydriodic acid using methylammonium lead iodide in dynamic equilibrium with aqueous solution

    Science.gov (United States)

    Park, Sunghak; Chang, Woo Je; Lee, Chan Woo; Park, Sangbaek; Ahn, Hyo-Yong; Nam, Ki Tae

    2017-01-01

    The solar-driven splitting of hydrohalic acids (HX) is an important and fast growing research direction for H2 production. In addition to the hydrogen, the resulting chemicals (X2/X3-) can be used to propagate a continuous process in a closed cycle and are themselves useful products. Here we present a strategy for photocatalytic hydrogen iodide (HI) splitting using methylammonium lead iodide (MAPbI3) in an effort to develop a cost-effective and easily scalable process. Considering that MAPbI3 is a water-soluble ionic compound, we exploit the dynamic equilibrium of the dissolution and precipitation of MAPbI3 in saturated aqueous solutions. The I- and H+ concentrations of the aqueous solution are determined to be the critical parameters for the stabilization of the tetragonal MAPbI3 phase. Stable and efficient H2 production under visible light irradiation was demonstrated. The solar HI splitting efficiency of MAPbI3 was 0.81% when using Pt as a cocatalyst.

  16. Inhibition of acid corrosion of steel by some S-alkylisothiouronium iodides

    Energy Technology Data Exchange (ETDEWEB)

    Arab, S.T.; Noor, E.A. (Girl' s Coll. of Education, Jeddah (Saudi Arabia))

    1993-02-01

    Five selected S-alkylisothisothiouronium iodides have been studied as acid corrosion inhibitors at 30 C for steel in 0.5 M H[sub 2]SO[sub 4] using gasometry, mass loss, and direct current (DC) polarization techniques. All of the data reveal that the compounds act as inhibitors in the acid environments; furthermore, polarization curves show that the compounds act as mixed-type inhibitors. It was found that the inhibition efficiency increases with the increase of the length of the additive alkyl chain. Langmuir's adsorption isotherms fit the experimental data for the studied compounds. Thermodynamic parameter were obtained from experimental data of the temperature studies of the inhibition process at five temperatures ranging from 30 to 70 C. It was observed that the activation energy is slightly increased with the increase of the additive alkyl chain. On the other hand, the sudden large increase of the inhibition behavior of S-hexylisothiouronium iodide was attributed to a different adsorption process.

  17. Sodium Iodide Symporter for Nuclear Molecular Imaging and Gene Therapy: From Bedside to Bench and Back

    Directory of Open Access Journals (Sweden)

    Byeong-Cheol Ahn

    2012-01-01

    Full Text Available Molecular imaging, defined as the visual representation, characterization and quantification of biological processes at the cellular and subcellular levels within intact living organisms, can be obtained by various imaging technologies, including nuclear imaging methods. Imaging of normal thyroid tissue and differentiated thyroid cancer, and treatment of thyroid cancer with radioiodine rely on the expression of the sodium iodide symporter (NIS in these cells. NIS is an intrinsic membrane protein with 13 transmembrane domains and it takes up iodide into the cytosol from the extracellular fluid. By transferring NIS function to various cells via gene transfer, the cells can be visualized with gamma or positron emitting radioisotopes such as Tc-99m, I-123, I-131, I-124 and F-18 tetrafluoroborate, which are accumulated by NIS. They can also be treated with beta- or alpha-emitting radionuclides, such as I-131, Re-186, Re-188 and At-211, which are also accumulated by NIS. This article demonstrates the diagnostic and therapeutic applications of NIS as a radionuclide-based reporter gene for trafficking cells and a therapeutic gene for treating cancers.

  18. Chitosan finishing nonwoven textiles loaded with silver and iodide for antibacterial wound dressing applications.

    Science.gov (United States)

    Aubert-Viard, François; Martin, Adeline; Chai, Feng; Neut, Christel; Tabary, Nicolas; Martel, Bernard; Blanchemain, Nicolas

    2015-03-02

    Polyethylene terephtalate (PET) and Polypropylene (PP) textiles are widely used in biomedical application such as wound dressings and implants. The aim of this work was to develop an antibacterial chitosan (CHT) coating activated by silver or by iodine. Chitosan was immobilized onto PET and PP supports using citric acid (CTR) as a crosslinking agent through a pad-dry-cure textile finishing process. Interestingly, depending on the CHT/CTR molar ratio, two different systems were obtained: rich in cationic ammonium groups when the CTR concentration was 1%w/v, and rich in anionic carboxylate groups when the CTR concentration was 10%w/v. As a consequence, such samples could be selectively loaded with iodine and silver nitrate, respectively.Both types of coatings were analyzed using SEM and FTIR, their sorption capacities were evaluated toward iodide/iodate anions (I(-)/IO3(-)) and the silver cations (Ag(+)) were evaluated using elemental analysis. Finally, in vitro evaluations were carried out to evaluate the cytocompatibility on the epithelial cell line. The silver loaded textile reported a stronger antibacterial effect against E.coli (5 log10 reduction) than toward S. aureus (3 log10) while the antibacterial effect of the iodide loaded textiles was limited to 1 log10 to 2 log10 on both strains.

  19. The effect of potassium iodide on the production of acid phosphatase by Sporothrix schenckii

    Directory of Open Access Journals (Sweden)

    P. S. Grover

    2003-06-01

    Full Text Available The present study was undertaken to find out the in vitro effect of potassium iodide (KI on the production of acid phosphatase by fully characterized strain of S.schenckii isolated from a patient of Cutaneous Sporotrichosis. The enzyme acid phosphatase was estimated during the 3 phases of growth of S.schenckii, without and with three concentrations of KI incorporated in the culture medium. In the control and in the test proper, with various concentrations of KI, no adverse effect of KI was observed on the production of acid phosphatase in early and mid log phase of fungal growth. Whereas in the exponential phase in test proper, there was a statistical significant decrease in the enzyme production with 0.8% and 3.2% of KI. The low activity at 0.8% and 3.2% KI indicates that KI has inhibitory effect on the growth of S.schenckii and has led to decrease in the activity of the enzyme. (Med J Indones 2003; 12: 65-8 Keywords: S.schenckii, acid phosphatase, potassium iodide

  20. Serum and tissue iodine concentrations in rats fed diets supplemented with kombu powder or potassium iodide.

    Science.gov (United States)

    Yoshida, Munehiro; Mukama, Ayumi; Hosomi, Ryota; Fukunaga, Kenji; Nishiyama, Toshimasa

    2014-01-01

    Serum and tissue iodine concentration was measured in rats fed a diet supplemented with powdered kombu (Saccharina sculpera) or potassium iodide to evaluate the absorption of iodine from kombu. Eighteen male 5-wk-old Wistar rats were divided into three groups and fed a basal AIN93G diet (iodine content, 0.2 mg/kg) or the basal diet supplemented with iodine (183 mg/kg) either in the form of kombu powder or potassium iodine (KI) for 4 wk. There were no differences in weight gain or serum biochemistry tests (alanine aminotransferase and aspartate aminotransferase activity, and total serum cholesterol and triglyceride concentration) after iodine supplementation. In addition, serum levels of the thyroid hormones thyroxine and triiodothyronine, as well as thyroid-stimulating hormone, were not affected. On the other hand, serum and tissue (thyroid, liver and kidney) iodine concentrations were markedly elevated after iodine supplementation. There was no difference in thyroid iodine concentration between KI and kombu supplementation. However, there was a significant difference observed in the iodine concentrations of serum, liver and kidney between the two iodine sources; rats fed KI had iodine concentrations in these tissues 1.8 to 1.9 times higher than those in rats fed kombu powder. These results suggest that the absorption of iodine from kombu is reduced compared to that from potassium iodide.

  1. Toxicity of tetramethylammonium hydroxide to aquatic organisms and its synergistic action with potassium iodide.

    Science.gov (United States)

    Mori, Izumi C; Arias-Barreiro, Carlos R; Koutsaftis, Apostolos; Ogo, Atsushi; Kawano, Tomonori; Yoshizuka, Kazuharu; Inayat-Hussain, Salmaan H; Aoyama, Isao

    2015-02-01

    The aquatic ecotoxicity of chemicals involved in the manufacturing process of thin film transistor liquid crystal displays was assessed with a battery of four selected acute toxicity bioassays. We focused on tetramethylammonium hydroxide (TMAH, CAS No. 75-59-2), a widely utilized etchant. The toxicity of TMAH was low when tested in the 72 h-algal growth inhibition test (Pseudokirchneriellia subcapitata, EC50=360 mg L(-1)) and the Microtox® test (Vibrio fischeri, IC50=6.4 g L(-1)). In contrast, the 24h-microcrustacean immobilization and the 96 h-fish mortality tests showed relatively higher toxicity (Daphnia magna, EC50=32 mg L(-1) and Oryzias latipes, LC50=154 mg L(-1)). Isobologram and mixture toxicity index analyses revealed apparent synergism of the mixture of TMAH and potassium iodide when examined with the D. magna immobilization test. The synergistic action was unique to iodide over other halide salts i.e. fluoride, chloride and bromide. Quaternary ammonium ions with longer alkyl chains such as tetraethylammonium and tetrabutylammonium were more toxic than TMAH in the D. magna immobilization test.

  2. Iodine in raw and pasteurized milk of dairy cows fed different amounts of potassium iodide.

    Science.gov (United States)

    Norouzian, M A

    2011-02-01

    Relation between iodine (I) intake by lactating Holstein cows and iodine concentrations in raw and pasteurized milk were investigated. Four treatment groups with eight cows assigned to each treatment were fed a basal diet containing 0.534 mg I/kg alone or supplemented with potassium iodide at 2.5, 5 or 7.5 mg/kg in 7-week period. Iodine concentrations in raw milk increased with each increase in dietary I from 162.2 ng/ml for basal diet to 534.5, 559.8 and 607.5 ng/ml when 2.5, 5 and 7.5 mg/kg was fed as potassium iodide (P < 0.05). This trend was found for blood plasma and urine iodine concentration. Iodine supplementation had no significant effect on thyroidal hormones. high-temperature short-time (HTST) pasteurization process reduced I concentration. The mean iodine content found in the milk prior to heating processing was 466.0 ± 205.0 ng/ml, whereas for the processed milk this level was 349.5 ± 172.8 ng/ml. It was concluded that iodine supplementation above of NRC recommendation (0.5 mg/kg diet DM) resulted in significant increases in iodine concentrations in milk, although the effect of heating in HTST pasteurization process on iodine concentration was not negligible.

  3. Characterization of thermally evaporated lead iodide films aimed for the detection of X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Caldeira Filho, A.M. [Departamento de Fisica, Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo - USP, Avenida Bandeirantes 3900, 14040-901, Ribeirao Preto-SP (Brazil); Mulato, M., E-mail: mmulato@ffclrp.usp.b [Departamento de Fisica, Faculdade de Filosofia, Ciencias e Letras de Ribeirao Preto, Universidade de Sao Paulo - USP, Avenida Bandeirantes 3900, 14040-901, Ribeirao Preto-SP (Brazil)

    2011-04-21

    Some semiconductor materials such as lead iodide (PbI{sub 2}) have applications in the detection of ionizing radiation at room temperature using the direct detection method. In this work we investigate lead iodide films deposited by thermal evaporation. The morphology, structure, and electric properties were investigated as a function of deposition height, i.e. the distance between evaporation-boat and substrates. The results show a morphology of vertical leaves and X-ray diffraction shows just one preferential orientation along the direction 110. Energy dispersive spectroscopy reveals that the films are not stoichiometric, with excess iodine atoms. Electrical resistivity of about 10{sup 8} {Omega} cm was measured. This is smaller than for the bulk due to structural defects. The values of activation energy for electric transport increase from 0.52 up to 1.1 eV with decreasing deposition height, what indicates that the best film is the one deposited at the shortest distance. Exposure under X-ray mammographic energy shows a linear behavior up to 500 mR. No variation in sensibility was observed between 22 and 30 kVp.

  4. Administration of additional inactive iodide during radioiodine therapy for Graves' disease. Who might benefit?

    Energy Technology Data Exchange (ETDEWEB)

    Dietlein, M.; Moka, D.; Reinholz, U.; Schmidt, M.; Schomaecker, K.; Schicha, H.; Wellner, U. [Koeln Univ. (Germany). Dept. of Nuclear Medicine

    2007-07-01

    Aim: Graves' hyperthyroidism and antithyroid drugs empty the intrathyroid stores of hormones and iodine. The consequence is rapid {sup 131}I turnover and impending failure of radioiodine therapy. Can administration of additional inactive iodide improve 131I kinetics? Patients, methods: Fifteen consecutive patients, in whom the 48 h post-therapeutically calculated thyroid dose was between 150 and 249 Gy due to an unexpectedly short half-life, received 3 x 200 {mu}g inactive potassium-iodide ({sup 127}I) daily for 3 days (Group A), while 17 consecutive patients with a thyroid dose of = 250 Gy (Group B) served as the non-iodide group. 48 hours after {sup 131}I administration (M1) and 4 or 5 days later (M2) the following parameters were compared: effective {sup 131}I half-life, thyroid dose, total T3, total T4, {sup 131}I-activity in the T3- and T4-RIAs. Results: In Group A, the effective {sup 131}I half-life M1 before iodine (3.81 {+-} 0.93 days) was significantly (p <0.01) shorter than the effective {sup 131}I half-life M2 (4.65 {+-} 0.79 days). Effective {sup 131}I half-life M1 correlated with the benefit from inactive {sup 127}I (r = -0.79): Administration of {sup 127}I was beneficial in patients with an effective {sup 131}I half-life M1 of <3 or 4 days. Patients from Group A with high initial specific {sup 131}I activity of T3 and T4 showed lower specific {sup 131}I activity after addition of inactive iodine compared with patients from the same group with a lower initial specific {sup 131}I activity of T3 and T4 and compared with the patient group B who was given no additional inactive iodide. This correlation was mathematically described and reflected in the flatter gradient in Group A (y = 0.5195x + 0.8727 for {sup 131}I T3 and y = 1.0827x - 0.4444 for {sup 131}I T4) and steeper gradient for Group B (y = 0.6998x + 0.5417 for {sup 131}I T3 and y = 1.3191x - 0.2901 for {sup 131}I T4). Radioiodine therapy was successful in all 15 patients from Group A

  5. Replacement of monochromator and proportional gas counter by mercuric iodide detector in X-ray powder diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Nissenbaum, J.; Levi, A.; Burger, A.; Schieber, M. (Hebrew Univ., Jerusalem (Israel). School of Applied Science and Technology)

    1983-02-01

    Low resolution and therefore low-cost mercuric iodide detectors have successfully been applied to replace the combination of a graphite monochromator and a proportional gas radiation counter used in X-ray diffractometers. The mercuric iodide detector requires a lower DC bias of only 200 V rather than the 1500 V bias needed for the proportional gas counter. The much better stopping power of HgI/sub 2/ allows higher counting efficiency and therefore a better signal-to-noise ratio. Results are shown for X-ray powder diffractions of polycrystalline cubic silicon and tetragonal HgI/sub 2/.

  6. Inner Sphere and Outer Sphere Electron Transfer to Methyl Iodide. Deuterium and 13C Kinetic Isotope Effects

    DEFF Research Database (Denmark)

    Holm, Torkil; Crossland, Ingolf

    1996-01-01

    Deuterium and 13C kinetic isotope effects (KIEs) have been determined for the conversion of methyl iodide into methyl radical via inner sphere ET (electron transfer) and via outer sphere ET. The alfa-deuterium KIE was found to be very high for in......Deuterium and 13C kinetic isotope effects (KIEs) have been determined for the conversion of methyl iodide into methyl radical via inner sphere ET (electron transfer) and via outer sphere ET. The alfa-deuterium KIE was found to be very high for in...

  7. Constraining the sensitivity of iodide adduct chemical ionization mass spectrometry to multifunctional organic molecules using the collision limit and thermodynamic stability of iodide ion adducts

    Science.gov (United States)

    Lopez-Hilfiker, Felipe D.; Iyer, Siddarth; Mohr, Claudia; Lee, Ben H.; D'Ambro, Emma L.; Kurtén, Theo; Thornton, Joel A.

    2016-04-01

    The sensitivity of a chemical ionization mass spectrometer (ions formed per number density of analytes) is fundamentally limited by the collision frequency between reagent ions and analytes, known as the collision limit, the ion-molecule reaction time, and the transmission efficiency of product ions to the detector. We use the response of a time-of-flight chemical ionization mass spectrometer (ToF-CIMS) to N2O5, known to react with iodide at the collision limit, to constrain the combined effects of ion-molecule reaction time, which is strongly influenced by mixing and ion losses in the ion-molecule reaction drift tube. A mass spectrometric voltage scanning procedure elucidates the relative binding energies of the ion adducts, which influence the transmission efficiency of molecular ions through the electric fields within the vacuum chamber. Together, this information provides a critical constraint on the sensitivity of a ToF-CIMS towards a wide suite of routinely detected multifunctional organic molecules for which no calibration standards exist. We describe the scanning procedure and collision limit determination, and we show results from the application of these constraints to the measurement of organic aerosol composition at two different field locations.

  8. Application of antimony ethylene glycol as a polycondensation catalyst%缩聚催化剂乙二醇锑的应用

    Institute of Scientific and Technical Information of China (English)

    林菘; 朱国明; 王玉龙

    2001-01-01

    The application process of antimony ethylene glycol as a polycondensation catalyst in PET plant was intro duced. The characteristic of compounding and adding of antimony ethylene glycol, its effect on polyester mannfacturing process and polyester product and the effect on spinning afterprocessing properties were discribed.%介绍了聚酯缩聚催化剂乙二醇锑在上海石化涤纶部的试用和推广应用过程,讲述了乙二醇锑的配制和添加的特点,对聚酯生产过程和对聚酯产品的影响,以及乙二醇锑的聚酯产品对纺丝后加工性能的影响。

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

    Science.gov (United States)

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

    1982-01-01

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

  10. Effectiveness of meglumine antimoniate against L. tropica in a recently emerged focus of cutaneous leishmaniasis in Birjand, eastern Islamic Republic of Iran.

    Science.gov (United States)

    Karamian, M; Bojd, M S Faroghi; Salehabadi, A; Hemmati, M; Barati, D A

    2015-06-09

    With limited options to treat cutaneous leishmaniasis, constant monitoring of the rate of resistance to pentavalent antimony-based drugs is needed. This study identified the infecting Leishmania species and evaluated the results of meglumine antimoniate (Glucantime®) therapy in a new focus of cutaneous leishmaniasis in Birjand, eastern Islamic Republic of Iran. Smears from 150 patients showed that 141 patients were infected by L. tropica and 9 by L. major. In total, 141 patients with L. tropica infection completed Glucantime® treatment and follow-up; 63.8% were treated intralesionally and 36.2% by intramuscular administration. The overall success rate after one course of therapy with Glucantime® was 96.5% (136/141), and all the failures (5/141) occurred with intramuscular injections. Statistical analysis showed a significant difference between the failure rates of intramuscular and intralesional injections. Children < 10 years old had a significantly higher failure rate than adults.

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

    Science.gov (United States)

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

    2015-06-01

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

  12. Iodide Impurities in Hexadecyltrimethylammonium Bromide (CTAB) Products: Lot−Lot Variations and Influence on Gold Nanorod Synthesis

    NARCIS (Netherlands)

    Rayavarapu, Raja Gopal; Ungureanu, Constantin; Krystec, Petra; Leeuwen, van Ton G.; Manohar, Srirang

    2010-01-01

    Recent reports [Smith and Korgel Langmuir 2008, 24, 644−649 and Smith et al.Langmuir 2009, 25, 9518−9524] have implicated certain hexadecyltrimethylammonium bromide (CTAB) products with iodide impurities, in the failure of a seed-mediated, silver and surfactant-assisted growth protocol, to produce g

  13. Evaluation of iodide deficiency in the lactating rat and pup using a biologically based dose response (BBDR) Model***

    Science.gov (United States)

    A biologically-based dose response (BBDR) model for the hypothalamic-pituitary thyroid (HPT) axis in the lactating rat and nursing pup was developed to describe the perturbations caused by iodide deficiency on the 1-IPT axis. Model calibrations, carried out by adjusting key model...

  14. Evaluation of iodide deficiency in the lactating rat and pup using a biologically based dose-response model

    Science.gov (United States)

    A biologically-based dose response (BBDR) model for the hypothalamic-pituitary thyroid (BPT) axis in the lactating rat and nursing pup was developed to describe the perturbations caused by iodide deficiency on the HPT axis. Model calibrations, carried out by adjusting key model p...

  15. Congenital Hypothyroidism Caused by a PAX8 Gene Mutation Manifested as Sodium/Iodide Symporter Gene Defect

    Directory of Open Access Journals (Sweden)

    Wakako Jo

    2010-01-01

    Full Text Available Loss-of-function mutations of the PAX8 gene are considered to mainly cause congenital hypothyroidism (CH due to thyroid hypoplasia. However, some patients with PAX8 mutation have demonstrated a normal-sized thyroid gland. Here we report a CH patient caused by a PAX8 mutation, which manifested as iodide transport defect (ITD. Hypothyroidism was detected by neonatal screening and L-thyroxine replacement was started immediately. Although 123I scintigraphy at 5 years of age showed that the thyroid gland was in the normal position and of small size, his iodide trapping was low. The ratio of the saliva/plasma radioactive iodide was low. He did not have goiter; however laboratory findings suggested that he had partial ITD. Gene analyses showed that the sodium/iodide symporter (NIS gene was normal; instead, a mutation in the PAX8 gene causing R31H substitution was identified. The present report demonstrates that individuals with defective PAX8 can have partial ITD, and thus genetic analysis is useful for differential diagnosis.

  16. N,N-Dimethylbenzimidazolium iodide as a green catalyst for cross-coupling of aromatic aldehydeswith unactivated imines

    Directory of Open Access Journals (Sweden)

    Viwat Hahnvajana wong

    2016-03-01

    Full Text Available Cross-coupling of aromatic aldehydes with unactivated iminescatalyzed by N,N-dimethylbenzimidazolium iodide in ethanolic sodium hydroxide solution gave α-amino ketonesin satisfactory yields. Benzoin condensation and further oxidation of the resulted aroins also occurred as side reactions.

  17. Efficient Method for the Determination of the Activation Energy of the Iodide-Catalyzed Decomposition of Hydrogen Peroxide

    Science.gov (United States)

    Sweeney, William; Lee, James; Abid, Nauman; DeMeo, Stephen

    2014-01-01

    An experiment is described that determines the activation energy (E[subscript a]) of the iodide-catalyzed decomposition reaction of hydrogen peroxide in a much more efficient manner than previously reported in the literature. Hydrogen peroxide, spontaneously or with a catalyst, decomposes to oxygen and water. Because the decomposition reaction is…

  18. The antimicrobial effect of apical box versus apical cone preparation using iodine potassium iodide as root canal dressing

    DEFF Research Database (Denmark)

    Markvart, Merete; Dahlén, Gunnar; Reit, Claes-Erik

    2013-01-01

    OCl (12 ml). Lastly, the canals were filled with 17% EDTA (2 × 30 s) and 5% iodine potassium iodide (IKI) for 10 min. The canals were sampled for micro-organisms on four occasions: before instrumentation, after instrumentation, after application of IKI dressing and at the beginning of the second...

  19. Selective copper(II acetate and potassium iodide catalyzed oxidation of aminals to dihydroquinazoline and quinazolinone alkaloids

    Directory of Open Access Journals (Sweden)

    Matthew T. Richers

    2013-06-01

    Full Text Available Copper(II acetate/acetic acid/O2 and potassium iodide/tert-butylhydroperoxide systems are shown to affect the selective oxidation of ring-fused aminals to dihydroquinazolines and quinazolinones, respectively. These methods enable the facile preparation of a number of quinazoline alkaloid natural products and their analogues.

  20. Potassium iodide catalyzed simultaneous C3-formylation and N-aminomethylation of indoles with 4-substituted-N,N-dimethylanilines.

    Science.gov (United States)

    Li, Lan-Tao; Li, Hong-Ying; Xing, Li-Juan; Wen, Li-Juan; Wang, Peng; Wang, Bin

    2012-12-28

    A one-pot dual functionalization of indoles has been developed. The simultaneous C3-formylation and N-aminomethylation of indoles can be achieved using readily available potassium iodide as a catalyst and tert-butyl peroxybenzoate as a co-oxidant.