WorldWideScience

Sample records for heavy sn sb

  1. Liquidus Projection and Isothermal Section of the Sb-Se-Sn System

    Science.gov (United States)

    Chang, Jui-shen; Chen, Sinn-wen

    2017-12-01

    Sb-Se-Sn ternary alloys are promising chalcogenide materials. The liquidus projection and 673.2 K (400 °C) isothermal section of the Sb-Se-Sn ternary system are determined. Numerous Sb-Se-Sn alloys are prepared, and their primary solidification phases are examined. In addition to the three terminal phases, (Sb), (Se) and (Sn), there are Sb2Sn3, SbSn, SnSe, SnSe2, Sb2Se3, Sn2Sb9Se9, and SnSb2Se4 phases. In addition, there are two miscibility gaps along the Sb-Se and Se-Sn and sides. There are ten invariant reactions in the Sb-Se-Sn ternary system, and seven of them are experimentally determined in this study. The lowest reaction temperature of determined invariant reaction is L + SbSn = (Sn) + SnSe at 515.4 K ± 5 K (242.2 °C ± 5 °C). There are nine tie-triangles, which are Liquid + SbSn + SnSe, SbSn + SnSe + (Sb), SnSe + (Sb) + Sn2Sb9Se9, (Sb) + Sb2Se3 + Sn2Sb9Se9, SnSe + Sn2Sb9Se9 + SnSb2Se4, Sb2Se3 + Sn2Sb9Se9 + SnSb2Se4, SnSe + SnSe2 + SnSb2Se4, SnSe2 + SnSb2Se4 + Sb2Se3, and SnSe2 + Sb2Se3 + Liquid in the 673.2 K (400 °C) isothermal section of the Sb-Se-Sn ternary system.

  2. {sup 119}Sn CEMS study of Sb doped SnO{sub 2} film

    Energy Technology Data Exchange (ETDEWEB)

    Nomura, K., E-mail: dqf10204@nifty.com [Tokyo University of Science, PIRC (Japan); Kuzmann, E., E-mail: kuzmann@caesar.elte.hu [Eötvös Loránd University, Pázmány Péter sétány 1/A, Institute of Chemistry (Hungary); Garg, V. K.; Oliveira, A. C. de [University of Brasília, Institute of Physics (Brazil); Stichleutner, S.; Homonnay, Z. [Eötvös Loránd University, Pázmány Péter sétány 1/A, Institute of Chemistry (Hungary)

    2016-12-15

    Sb doped SnO{sub 2} films prepared by DC sputtering and heating were characterized by {sup 119}Sn conversion electron Mössbauer spectrometry (CEMS). An asymmetric doublet was observed in the Mössbauer spectra of 1 %, 3 %, and 10 % Sb doped SnO{sub 2} films. The peak ratios of doublets are considered to be due to the columnar crystal growth on the substrate. With the doping level of Sb, both the isomer shift (δ) and the quadrupole splitting (Δ) increased. After annealing, δ increased and Δ decreased for each sample. These results suggest the followings. The electron doping of the SnO{sub 2} lattice by pentavalent Sb induces the increase of the electron density at the Sn{sup IV} nucleus. The annealing process leads to more complete accommodation of the Sb dopant that results in more effective electron doping and therefore increasing isomer shift for tin. Simultaneously, the distortion of the lattice caused by Sb is relaxed and the quadrupole splitting decreases.

  3. Microstructure evolution of directionally solidifi ed Sn-16%Sb hyperperitectic alloy

    Directory of Open Access Journals (Sweden)

    Li Shuangming

    2008-11-01

    Full Text Available The directionally solidifi ed microstructure of Sn-16%Sb hyperperitectic alloy has been investigated at various solidifi cation rates using a high-thermal gradient directional solidifi cation apparatus. The results indicate that the solidifi cation microstructure consists of hard primary intermetallic SnSb phase embedded in a matrix of soft peritectic β-Sn phase. The primary SnSb phase exhibits faceted growth with tetragonal or trigonal shapes. At the same time, the primary SnSb phase is refi ned with an increase in the solidifi cation rate and dispersed more uniformly in the matrix of β-Sn phase. The volume fraction of the SnSb phase fi rstly decreases and then increases when the solidifi cation rate increases in directional solidifi cation of Sn-16%Sb hyperperitectic alloy.

  4. Sb-Doped SnO2 Nanoparticles Synthesized by Sonochemical-Assisted Precipitation Process.

    Science.gov (United States)

    Noonuruk, Russameeruk; Vittayakorn, Naratip; Mekprasart, Wanichaya; Sritharathikhun, Jaran; Pecharapa, Wisanu

    2015-03-01

    Sb-doped SnO2 nanopowders were synthesized by sonochemical-assisted precipitation process using stannic chloride pentahydrate (SnCl4.5H2O) and antimony chloride (SbC3) as starting precursors. Effect of sonication and Sb doping concentrations on physical structures and electrical properties of Sb-doped SnO2 nanoparticles were investigated by X-ray diffraction, transmission electron microscope, X-ray photoelectron spectroscopy, Raman spectroscopy and two-point probe method. The results indicated that the good dispersion with less agglomeration of particles in SnO2 phase can be obtained by single step sonochemical-assisted process. Moreover, XRD results indicated that the crystallinity of Sb-doped SnO2 nanopowders deteriorated with increasing Sb content, suggesting that Sb dopant significantly prevent SnO2 crystallite growth. The XPS spectra of Sb-doped SnO2 obviously confirmed the existence of Sb ion incorporated into SnO2 matrix. These results revealed that incorporation of Sb ions into SnO2 lattice with specific concentration has significant influence on formation and crystallization and can dramatically enhance the conductivity of tin oxide.

  5. Electrochemical studies of CNT/Si–SnSb nanoparticles for lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Nithyadharseni, P. [Department of Physics, Bannari Amman Institute of Technology, Sathyamangalam 638402 (India); Department of Physics, Advanced Batteries Lab, National University of Singapore, 117542 (Singapore); Reddy, M.V., E-mail: phymvvr@nus.edu.sg [Department of Physics, Advanced Batteries Lab, National University of Singapore, 117542 (Singapore); Nalini, B., E-mail: lalin99@rediffmail.com [Department of Physics, Avinashilingam University for Women, Coimbatore 641043 (India); Ravindran, T.R. [Centre for Research in Nanotechnology, Karunya University, Coimbatore 641114 (India); Pillai, B.C.; Kalpana, M. [Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam 603102 (India); Chowdari, B.V.R. [Department of Physics, Advanced Batteries Lab, National University of Singapore, 117542 (Singapore)

    2015-10-15

    Highlights: • Si added SnSb and CNT exhibits very low particle size of below 30 nm • A strong PL quenching due to the addition of Si to SnSb. • Electrochemical studies show CNT added SnSb shows good capacity retention. - Abstract: Nano-structured SnSb, SnSb–CNT, Si–SnSb and Si–SnSb–CNT alloys were synthesized from metal chlorides of Sn, Sb and Si via reductive co-precipitation technique using NaBH{sub 4} as reducing agent. The as prepared compounds were characterized by various techniques such as X-ray diffraction (XRD), scanning electron microscope (SEM), Raman, Fourier transform infra-red (FTIR) and photoluminescence (PL) spectroscopy. The electrochemical performances of the compounds were characterized by galvanostatic cycling (GC) and cyclic voltammetry (CV). The Si–SnSb–CNT compound shows a high reversible capacity of 1200 mAh g{sup −1}. However, the rapid capacity fading was observed during cycling. In contrast, SnSb–CNT compound showed a high reversible capacity of 568 mAh g{sup −1} at 30th cycles with good cycling stability. The improved reversible capacity and cyclic performance of the SnSb–CNT compound could be attributed to the nanosacle dimension of SnSb particles and the structural advantage of CNTs.

  6. The Effect of Sb Addition on Sn-Based Alloys for High-Temperature Lead-Free Solders: an Investigation of the Ag-Sb-Sn System

    Science.gov (United States)

    Li, D.; Delsante, S.; Watson, A.; Borzone, G.

    2012-01-01

    Today there is renewed interest in alloys belonging to the Sb-Sn-X (X = Cu, Ag, Bi) ternary systems and their phase equilibria, phase transformations, and thermodynamic properties because of their possible use as high-temperature lead-free solders in the electronics industry. The integral mixing enthalpy of Ag-Sb-Sn liquid alloys has been measured along five different sections (Ag0.25Sn0.75, Ag0.50Sn0.50, Sb0.30Sn0.70, Sb0.50Sn0.50, and Sb0.70Sn0.30) at 530°C, 600°C, and 630°C, using a high-temperature Calvet calorimeter by dropping pure elements (Ag or Sb) in the binary alloy liquid bath. The ternary extrapolation models of Muggianu and Toop were used to calculate the integral enthalpy of mixing and to compare measured and extrapolated values. Selected ternary alloys have been prepared for thermal investigation by using a differential scanning calorimeter at different heating/cooling rates in order to clarify the temperature of the invariant reactions and the crystallization path.

  7. Viscoelastic behavior over a wide range of time and frequency in tin alloys: SnCd and SnSb

    Energy Technology Data Exchange (ETDEWEB)

    Quackenbush, J.; Brodt, M.; Lakes, R.S. [Univ. of Iowa, Iowa City, IA (United States)

    1996-08-01

    All materials exhibit some viscoelastic response, which can manifest itself as creep, relaxation, or, if the load is sinusoidal in time, a phase angle {delta} between stress and strain. Recently, a study of pure elements with low melting points, Cd, In, Pb, and Sn disclosed that cadmium exhibited a substantial loss tangent of 0.03 to 0.04 over much of the audio range of frequencies, combined with a moderate stiffness G = 20.7 GPa. Lead, by contrast, exhibited tan {delta} of 0.005 to 0.016 in the audio range. Indium exhibited a high loss tangent exceeding 0.1 at very low frequency. A eutectic alloy of indium and tin was found to exhibit substantial damping exceeding 0.1 below 0.1 Hz, and this alloy was used to make a composite exhibiting high stiffness and high damping. It is the purpose of this communication to present viscoelastic properties of two additional low melting point alloys, SnCd and SnSb. Both InSn and SnSb are used as solders. Although the melting point of Sb is 630.74 C, T{sub H} > 0.55 at ambient temperature for the alloy of SnSb (95 wt% Sn/5 wt% Sb) which melts near 240 C. Eutectic SnCd melts at 177 C so T{sub H} {approx} 0.65 at room temperature.

  8. Rapid solidification mechanism of highly undercooled ternary Cu40Sn45Sb15 alloy

    Science.gov (United States)

    Zhai, W.; Wang, B. J.; Lu, X. Y.; Wei, B.

    2015-10-01

    The rapid solidification of ternary Cu40Sn45Sb15 peri-eutectic type alloy was realized by glass fluxing and drop tube methods, and the corresponding maximum undercoolings are 185 K (0.22 T L) and 321 K (0.39 T L), respectively. The phase constitution of Cu40Sn45Sb15 alloy in these two rapid solidification experiments deviates from the two equilibrium phases (Sn + Cu6Sn5). In glass fluxing method, the structural morphology of Cu40Sn45Sb15 alloy is mainly characterized by a three-layer lamellar structure, which is comprised by an inner layer of long strips of primary ɛ(Cu3Sn) phase, an intermediate layer of η(Cu6Sn5) phase and an outer layer of β(SnSb) phase. As undercooling rises, this lamellar structure is remarkably refined. When small alloy droplets are containerlessly solidified during free fall in drop tube, the primary ɛ(Cu3Sn) phase grows by non-faceted mode into dendrites as droplet diameter decreases. Especially, solidification path alters in the smallest droplet with 50 μm diameter, in which η(Cu6Sn5) and Sn3Sb2 phases form directly from the metastable liquid phase by suppressing the primary ɛ phase formation and the following peri-eutectic transformation.

  9. Thermoelectric Properties of SnO2 Ceramics Doped with Sb and Zn

    DEFF Research Database (Denmark)

    Yanagiya, S.; Van Nong, Ngo; Xu, Jianxiao Jackie

    2011-01-01

    Polycrystalline SnO2-based samples (Sn0.97−x Sb0.03Zn x O2, x = 0, 0.01, 0.03) were prepared by solid-state reactions. The thermoelectric properties of SnO2 doped with Sb and Zn were investigated from 300 K to 1100 K. X-ray diffraction (XRD) analysis revealed all XRD peaks of all the samples as i...

  10. Room temperature synthesis of crystalline Sb2S3 for SnO2 ...

    Indian Academy of Sciences (India)

    494. Anil N Kulkarni et al mortar and pestle for 40 min, then SnO2 film was prepared on fluorine-doped tin oxide (FTO) glass by the doctor blade method.23 After drying, all samples were annealed at 450◦C for 1 h. Further the SnO2 films were immersed into Sb2S3 colloidal solution for 1 h to adsorb Sb2S3 nanoparticles onto.

  11. Sn-Sb-Se based binary and ternary alloys for phase change memory applications

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Kyung-Min

    2008-10-28

    In this work, the effect of replacing Ge by Sn and Te by Se was studied for a systematic understanding and prediction of new potential candidates for phase change random access memories applications. The temperature dependence of the electrical/structural properties and crystallization kinetics of the Sn-Se based binary and Sn-Sb-Se based ternary alloys were determined and compared with those of the GeTe and Ge-Sb-Te system. The temperature dependence of electrical and structural properties were investigated by van der Pauw measurements, X-ray diffraction, X-ray reflectometry. By varying the heating rate, the Kissinger analysis has been used to determine the combined activation barrier for crystallization. To screen the kinetics of crystallization, a static laser tester was employed. In case of binary alloys of the type Sn{sub x}Se{sub 1-x}, the most interesting candidate is SnSe{sub 2} since it crystallizes into a single crystalline phase and has high electrical contrast and reasonably high activation energy for crystallization. In addition, the SnSe{sub 2}-Sb{sub 2}Se{sub 3} pseudobinary alloy system also might be sufficient for data retention due to their higher transition temperature and activation energy for crystallization in comparison to GeTe-Sb{sub 2}Te{sub 3} system. Furthermore, SnSe{sub 2}-Sb{sub 2}Se{sub 3} pseudobinary alloys have a higher crystalline resistivity. The desired rapid crystallization speed can be obtained for Sn{sub 1}Sb{sub 2}Se{sub 5} and Sn{sub 2}Sb{sub 2}Se{sub 7} alloys. (orig.)

  12. Pt nanoparticles supported on Sb-doped SnO₂ porous structures: developments and issues.

    Science.gov (United States)

    Fabbri, E; Rabis, A; Kötz, R; Schmidt, T J

    2014-07-21

    In this work, high surface area antimony doped tin oxide (Sb-SnO2) has been synthesized using a modified sol-gel synthesis method. The bulk and surface properties of the metal oxide support have been investigated as a function of the processing conditions. A change in the Sb-SnO2 processing conditions, while preserving an overall invariant bulk composition, led to substantial modification of the surface stoichiometry. Accelerated stability test protocols have shown that the surface composition represents a crucial parameter for the electrochemical stability of Sb-SnO2. Model Pt/Sb-SnO2 electrodes have been developed depositing Pt nanoparticles by magnetron sputtering on the optimized Sb-SnO2 porous surface. A significant enhancement in the corrosion stability upon 1000 potential cycles between 0.5 and 1.5 V (RHE) at 50 mV s(-1) has been observed for the Pt/Sb-SnO2 system compared to Pt/carbon.

  13. Ternary Sn-Sb-Co alloy film as new negative electrode for lithium-ion cells

    Energy Technology Data Exchange (ETDEWEB)

    Tabuchi, T. [Institute for Chemical Technology of Inorganic Materials, Technical University of Graz, Stremayrgasse 16, Graz 8010 (Austria); Graduate School of Engineering, Kyoto University, Kyotodaigaku-katsura, Nishikyo-ku, Kyoto 615-8510 (Japan); Hochgatterer, N.; Winter, M. [Institute for Chemical Technology of Inorganic Materials, Technical University of Graz, Stremayrgasse 16, Graz 8010 (Austria); Ogumi, Z. [Graduate School of Engineering, Kyoto University, Kyotodaigaku-katsura, Nishikyo-ku, Kyoto 615-8510 (Japan)

    2009-03-15

    Ternary Sn-Sb-Co alloy film was successfully prepared by the co-electroplating method using an aqueous solution bath containing SnCl{sub 2}.2H{sub 2}O, CoCl{sub 2}, SbCl{sub 3}, Na{sub 2}C{sub 4}H{sub 4}O{sub 6}.2H{sub 2}O, K{sub 3}C{sub 6}H{sub 5}O{sub 7}.H{sub 2}O, and gelatine. The alloy composition was found to be mainly controllable by the amount of Na{sub 2}C{sub 4}H{sub 4}O{sub 6}.2H{sub 2}O and SbCl{sub 3} in the plating bath. The Sn-Sb-Co film electrode with a composition of 75.4% Sn, 6.5% Sb, and 18.1% Co gave an initial discharge capacity of 380 mAh g{sup -1}. The capacity gradually increased from the 1st to the 10th cycle and was then stabilized at a larger value of 580 mAh g{sup -1}. Furthermore, the electrode was found to give better cycle performance compared to binary Sn-Co and Sn-Sb alloys. (author)

  14. Efficient photocatalytic degradation of phenol in aqueous solution by SnO{sub 2}:Sb nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Al-Hamdi, Abdullah M., E-mail: Abdullah.Al.Hamdi@lut.fi [Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, 50130 Mikkeli (Finland); Chemistry Department, Sultan Qaboos University, P.O. Box 17, 123 Al-Khoudh (Oman); Chair in Nanotechnology, Water Research Center, Sultan Qaboos University, P.O. Box 17, 123 Al-Khoudh (Oman); Sillanpää, Mika [Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, 50130 Mikkeli (Finland); Bora, Tanujjal [Chair in Nanotechnology, Water Research Center, Sultan Qaboos University, P.O. Box 17, 123 Al-Khoudh (Oman); Dutta, Joydeep [Chair in Nanotechnology, Water Research Center, Sultan Qaboos University, P.O. Box 17, 123 Al-Khoudh (Oman); Functional Materials Division, ICT, KTH Royal Institute of Technology, Isafjordsgatan 22, SE-164 40 KistaStockholm (Sweden)

    2016-05-01

    Highlights: • Sb doped SnO{sub 2} nanoparticles were synthesized using sol–gel process. • Photocatalytic degradation of phenol were studies using SnO{sub 2}:Sb nanoparticles. • Under solar light phenol was degraded within 2 h. • Phenol mineralization and intermediates were investigated by using HPLC. - Abstract: Photodegradation of phenol in the presence of tin dioxide (SnO{sub 2}) nanoparticles under UV light irradiation is known to be an effective photocatalytic process. However, phenol degradation under solar light is less effective due to the large band gap of SnO{sub 2}. In this study antimony (Sb) doped tin dioxide (SnO{sub 2}) nanoparticles were prepared at a low temperature (80 °C) by a sol–gel method and studied for its photocatalytic activity with phenol as a test contaminant. The catalytic degradation of phenol in aqueous media was studied using high performance liquid chromatography and total organic carbon measurements. The change in the concentration of phenol affects the pH of the solution due to the by-products formed during the photo-oxidation of phenol. The photoactivity of SnO{sub 2}:Sb was found to be a maximum for 0.6 wt.% Sb doped SnO{sub 2} nanoparticles with 10 mg L{sup −1} phenol in water. Within 2 h of photodegradation, more than 95% of phenol could be removed under solar light irradiation.

  15. Investigation of multilayer SnSb4/ZnSb thin films for phase change memory applications

    Science.gov (United States)

    He, Zifang; Chen, Shiyu; Wu, Weihua; Zhai, Jiwei; Song, Sannian; Song, Zhitang

    2017-05-01

    Multilayer SnSb4/ZnSb (SS/ZS) thin films have been investigated for phase change applications. The composition [SS (4 nm)/ZS (10 nm)]4 exhibits a high crystallization temperature (T c ˜ 230 °C), high data retention temperature for 10 years (T 10-yr ˜ 152 °C), small density change, and low thermal conductivity. A cell based on [SS (4 nm)/ZS (10 nm)]4 achieves fast SET/RESET switching speed (˜10 ns) and low reset power consumption (the energy for RESET operation = 9.6 × 10-13 J).

  16. Synthesis, surface modification and ethanol sensing properties of Sb-doped SnO2

    Science.gov (United States)

    Huang, Jiarui; Yu, Kun; Zhukova, Anna A.; Rumyantseva, Marina N.; Gaskov, Alexandre M.; Wang, Junhai; Gu, Cuiping; Liu, Jinhuai

    2009-07-01

    Sb-doped SnO2 whiskers were prepared by thermal evaporation of mixture of SnO and Sb2O3 powders. And then the surface of the whisker was modified with the Au nanoparticles (Au NPs) by in situ reduction method. FE-SEM observations reveal that the synthesized products consist of a large number of whiskers. The Au NPs were homogeneously distributed on the surface of the whisker. The ethanol sensitive characteristics of single SnO2 whiskerbased sensors have been investigated. These sensors show good sensitivity, rapid response and recovery. The response and recovery time of the sensor is about 38-45 s and 125-150 s, respectively. It is found that the working temperature of the sensor decreases after the surface of Sb-doped whiskers modified with Au NPs. Compared to the unmodified Sbdoped SnO2 whisker, Au NPs modified Sb-doped SnO2 whisker exhibits greatly improvement of sensitivity which could be explained by the catalytic action of Au NPs. These results indicate that the Au NPs modifying the surface of SnO2 whiskers is important for improving its sensitivity and lowering the working temperature. This is the first step towards fundamental understanding of single-crystalline tin oxide whiskers for sensor applications, which could lead to integration in real devices.

  17. Flake structured SnSbCo/MCMB/C composite as high performance anodes for lithium ion battery

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xiaoqiu [School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006 (China); Engineering Research Center of Materials and Technology for Electrochemical Energy Storage (Ministry of Education), Guangzhou 510006 (China); Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006 (China); Guangdong Engineering Technology Research Center of Low Carbon and Advanced Energy Materials, Guangzhou 510631 (China); Ru, Qiang, E-mail: rq7702@yeah.net [School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006 (China); Engineering Research Center of Materials and Technology for Electrochemical Energy Storage (Ministry of Education), Guangzhou 510006 (China); Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006 (China); Guangdong Engineering Technology Research Center of Low Carbon and Advanced Energy Materials, Guangzhou 510631 (China); Zhao, Doudou; Mo, Yudi; Hu, Shejun [School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006 (China); Engineering Research Center of Materials and Technology for Electrochemical Energy Storage (Ministry of Education), Guangzhou 510006 (China); Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials, School of Physics and Telecommunication Engineering, South China Normal University, Guangzhou 510006 (China); Guangdong Engineering Technology Research Center of Low Carbon and Advanced Energy Materials, Guangzhou 510631 (China)

    2015-10-15

    SnSbCo/MCMB/C composite with flake structure were prepared by stepwise synthesis method. Firstly, SnSbCo nanoparticles were fabricated by co-precipitation, and then nanosized SnSbCo alloy were embedded in mesocarbon microbeads (MCMB) by ball-milling to synthesize primitive SnSbCo/MCMB hybrids, followed by carbonization of phenolic resin to produce an outer layer of carbon coating. The crystal structure, morphology and electrochemical properties of the SnSbCo/MCMB/C composite were evaluated by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and galvanostatical cycling tests. Compared with bare SnSbCo alloy and SnSbCo/MCMB hybrids, the efficiently enhanced electrochemical performance of SnSbCo/MCMB/C composite were mainly ascribed to the improved electron conductivity and volume buffering effect provided by the amorphous carbon coating. The resultant SnSbCo/MCMB/C composite delivered an initial discharge capacity of 848 mAh g{sup −1} under 100 mA g{sup −1}, with a good capacity retention of 85.6% after 70 cycles. The composite also exhibited excellent rate capability of 603 mAh g{sup −1} and 405 mAh g{sup −1} at the current density of 200 mA g{sup −1} and 1000 mA g{sup −1}, respectively. - Highlights: • Flake structured SnSbCo/MCMB/C composite have been prepared by stepwise synthesis method. • SnSbCo/MCMB/C composite show good cycle performance and rate capability. • Using both MCMB and phenolic resin as dual carbon sources.

  18. Preparation of PtSnSb/C electrocatalizers for the electro-oxidation of the ethanol; Preparacao de eletrocatalizadores PtSnSb/C para a eletrooxidacao do etanol

    Energy Technology Data Exchange (ETDEWEB)

    Tusi, M.M.; Ayoub, J.M.S.; Costa, T.C.; Spinace, E.V.; Neto, A.O., E-mail: aolivei@ipen.b, E-mail: espinace@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2010-07-01

    PtSn/C (Pt:Sn atomic ratio of 50:50) and PtSnSb/C (Pt:Sn:Sb atomic ratio of 50:45:05, 50:40:10 and 50:10:40) electrocatalysts were prepared (20 wt% metal loading) by an alcohol-reduction process using ethylene glycol as reducing agent, H{sub 2}PtCl{sub 6}.6H{sub 2}O, SnCl{sub 2}.H{sub 2}O and Sb(OOCCH{sub 3}){sub 3} and carbon Vulcan XC72 as support. The obtained materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and chronoamperometry. The PtSnSb/C (50:45:05) prepared by an alcohol-reduction process showed the best performance for ethanol electro-oxidation compared to the others catalysts. (author)

  19. Carbon-coated SnSb nanoparticles dispersed in reticular structured nanofibers for lithium-ion battery anodes

    Energy Technology Data Exchange (ETDEWEB)

    Niu, Xiao [College of Textiles and Clothing, Xin Jiang University, Xinjiang, Urumqi 830046 (China); Key Laboratory of Textile Science and Technology, Donghua University, Ministry of Education, Shanghai 201620 (China); Zhou, Huimin; Li, Zhiyong; Shan, Xiaohong [College of Textiles and Clothing, Xin Jiang University, Xinjiang, Urumqi 830046 (China); Xia, Xin, E-mail: xjxiaxin@163.com [College of Textiles and Clothing, Xin Jiang University, Xinjiang, Urumqi 830046 (China); Key Laboratory of Textile Science and Technology, Donghua University, Ministry of Education, Shanghai 201620 (China)

    2015-01-25

    Highlights: • Sn{sub 0.92}Sb{sub 0.08}O{sub 2.04} nanoparticles as SnSb alloy precursor. • Carbon-coated SnSb nanoparticles were prepared and then embedded in carbon nanofibers. • The synergic effect of carbon coating and special structure improved cycling stability. - Abstract: Carbon coating and carbon nanofiber processes were used to enhance the cycling performance of SnSb alloys. Carbon-coated SnSb alloys were firstly prepared by a simple hydrothermal method to build the first protection, and then carbon-coated SnSb nanoparticles were embedded in carbon nanofibers via single-spinneret electrospinning followed by carbonization. The crystal structure of carbon-coated SnSb/C hybrid nanofibers was characterized by X-ray diffraction (XRD). The morphologies of carbon-coated SnSb alloys and hybrid nanofibers were characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM), respectively. The thermal stability of hybrid nanofibers were determined by thermogravimetric analysis (TGA). The electrochemical properties were investigated as a potential high-capacity anode material for lithium-ion batteries. The results showed that the hybrid nanofibers exhibited excellent electrochemical performance due to the special structure. The carbon shell can effectively hinder the agglomeration of SnSb alloys, while maintaining electronic conduction as well as accommodating drastic volume changes during lithium insertion and extraction and carbon nanofibers formed a further protection. The resultant carbon-coated SnSb nanoparticles dispersed in carbon nanofibers deliver a high capacity of 674 mA h g{sup −1} and a good capacity retention of 68.7% after 50 cycles.

  20. GaSb grown from Sn solvent at low temperatures by LPE

    Energy Technology Data Exchange (ETDEWEB)

    Compean, V H; Anda, F de; Mishurnyi, V A; Gorbatchev, A Yu, E-mail: fdeanda@cactus.iico.uaslp.m [Universidad Autonoma de San Luis Potosi, Instituto de Investigacion en Comunicacion Optica, Av. Karakorum 1470, Col. Lomas 4a Sec., San Luis Potosi, SLP, CP 78210 (Mexico)

    2009-05-01

    The LPE growth of GaSb using Sn as a solvent has been studied in the temperature range 250-370 C and using liquid solutions covering a wide range of compositions. In order to find the growth conditions the phase diagram has been determined experimentally around the same temperature region. It is shown the Sn incorporates into the grown layers and that it behaves as an acceptor. The photoluminescence spectra of the grown layers with different Sn contents show characteristic peaks that can be attributed to different recombination processes.

  1. Preparation and Performance of Sb-SnO2 / Ti Electrode Modified with Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    WEI Jin-zhi

    2017-06-01

    Full Text Available In order to improve the electro-catalytic oxidation activity and stability of Sb-SnO2 /Ti electrode,the CNTs-Sb-SnO2 /Ti electrode was prepared by sol-gel-thermal decomposition method. The microstructure and electrochemical properties of the modified electrode was characterized via SEM electrochemical impedance spectroscope ( EIS ,polarization curve and congo red degradation experiments. Furthermore,its the stability was investigated by accelerated life test. The results indicate that when the optimal doping amount of CNTs is 2. 0 g /L the congo red removal rate increases by 14. 7% using the CNTs-Sb-SnO2 /Ti electrode compared with the Sb-SnO2 /Ti electrode. Meanwhile pore structure appears and roughness increases on the surface of modified electrodes leading to larger specific surface area of electrode. Then the modified electrodes exhibit higher oxygen evolution potential and lower charge transfer resistance. Additionally,accelerated life tests reveal that the modified electrode has better electro-catalytic stability while the service life increases by

  2. Solution route synthesis of InSb, Cu 6Sn 5 and Cu 2Sb electrodes for lithium batteries

    Science.gov (United States)

    Sarakonsri, T.; Johnson, C. S.; Hackney, S. A.; Thackeray, M. M.

    A solution method was used to prepare InSb, Cu 6Sn 5 and Cu 2Sb intermetallic compounds that are of interest as negative electrode materials for lithium batteries. The compounds were synthesized by the reduction of dissolved transition metal- and metalloid salts with fine Zn powder. Heterogeneous redox reactions at the surface of the Zn particles resulted in fern-like dendritic structures with high surface areas. Powder X-ray diffraction and lattice imaging by transmission electron microscopy showed that the intermetallic products were highly crystalline with preferred crystallographic orientations. Mild heat-treatment of the products under argon improved their phase purity. Electrodes prepared by this method exhibited a large irreversible capacity loss on the first charge/discharge cycle. Cu 2Sb electrodes showed the greatest cycling stability; after the initial cycle, they delivered more than 230 mAh g -1 when cycled between 1.2 and 0.0 V versus metallic lithium, consistent with previously reported data for ball-milled Cu 2Sb electrodes.

  3. Morphology and Hardness Improvement of Lead Bearing Alloy through Composite Production: 75Pb-15Sb-10Sn/ 15% V/V SiO2 Particulate Composite

    Directory of Open Access Journals (Sweden)

    Linus Okon ASUQUO

    2013-06-01

    Full Text Available The morphology and hardness improvement of lead bearing alloy through composite production: 75Pb-15Sb-10Sn/ 15%v/v SiO2 particulate composite, was studied. 75Pb-15Sb-10Sn white bearing alloy produced at the foundry shop of National Metallurgical Development Centre Jos was used for the production of the composite using stir-cast method. The reinforcing agent was 63 microns passing particles of silica. This was produced from pulverizing quartz using laboratory ball mill. The specimens of the composite produced were then subjected to metallographic to study the morphology of the structures produced both in the as cast and aged conditions of the composite. The samples were also tested for hardness and the result showed that the as cast composite had a hardness value of 33 HRB which is an improvement over the hardness value of 27.7 HRB for the 75Pb-15Sb-10Sn alloy which was used for the production of the composite. The effect of age hardening on the produced composite was also investigated; the result showed that the maximum hardness of 34 HRB was obtained after ageing for 3 hours. The micrographs revealed inter-metallic compound SbSn, eutectic of two solid solutions-one tin-rich and the other lead-rich, reinforcing particles, and solid solution of β. The results revealed that particle hardening can be used to improve the hardness of 75Pb-15Sb-10Sn white bearing alloy for use as heavy duty bearing material.

  4. Room-Temperature Indentation Creep and the Mechanical Properties of Rapidly Solidified Sn-Sb-Pb-Cu Alloys

    Science.gov (United States)

    Kamal, Mustafa; El-Bediwi, A.; Lashin, A. R.; El-Zarka, A. H.

    2016-05-01

    In this paper, we study the room-temperature indentation creep and the mechanical properties of Sn-Sb-Pb-Cu alloys. Rapid solidification from melt using the melt-spinning technique is applied to prepare all the alloys. The experimental results show that the magnitude of the creep displacement increases with the increase in both time and applied load, and the stress exponent increases with the increase in the copper content in the alloys which happens primarily due to the existence of the intermetallic compounds SbSn and Cu6Sn5. The calculated values of the stress exponent are in the range of 2.82 to 5.16, which are in good agreement with the values reported for the Sn-Sb-Pb-Cu alloys. We have also studied and analyzed the structure, elastic modulus, and internal friction of the Sn-Sb-Pb-Cu alloys.

  5. Magnetism and heavy fermions in YbRhSn and YbPtSn

    Energy Technology Data Exchange (ETDEWEB)

    Andraka, Bohdan [Department of Physics, University of Florida, P.O. Box 118440, Gainesville, Florida 32611-8440 (United States); Pietri, Richard [Department of Physics, University of Florida, P.O. Box 118440, Gainesville, Florida 32611-8440 (United States); Kaczorowski, Dariusz [W.Trzebiatowski Institute for Low Temperature and Structure Research, Polish Academy of Sciences, 50-950 Wroclaw 2, (Poland); Leithe-Jasper, A. [Institut fuer Physikalische Chemie der Universitaet Wien, Waehringerstrasse 42, A-1090 Vienna, (Austria); Rogl, P. [Institut fuer Physikalische Chemie der Universitaet Wien, Waehringerstrasse 42, A-1090 Vienna, (Austria)

    2000-05-01

    Isostructural YbRhSn and YbPtSn were studied by specific heat, electrical resistivity, and magnetoresistance. Both compounds order antiferromagnetically below 2 and 3.5 K, respectively. Above 4 K, they display a number of remarkable similarities including Kondo-like resistivity and large negative magnetoresistance. Scaling analysis of this magnetoresistance shows that it is due to the suppression of Kondo scattering in YbRhSn but has a ferromagnetic spin fluctuation character in YbPtSn. The heavy fermion state was confirmed in YbRhSn by low temperature specific heat measurements yielding {gamma} of about 1200 mJ/K2 mol. {gamma} for YbPtSn is of order 100 mJ/K2 mol only. (c) 2000 American Institute of Physics.

  6. Sb-SnO2 nanoparticles onto kaolinite rods: assembling process and interfacial investigation

    Science.gov (United States)

    Hu, Peiwei; Yang, Huaming

    2012-04-01

    In this article, we reported the synthesis of novel Sb-SnO2/kaolinite (SK) nanocomposites by assembling antimony-doped tin oxide (ATO) nanoparticles on the surface of kaolinite rods without addition of dispersant. The samples were characterized by X-ray diffraction, transmission electron microscopy (TEM), high-resolution TEM, X-ray photoelectron spectroscopy (XPS), and N2 adsorption-desorption techniques. The crystal size and loading density of ATO nanoparticles onto kaolinite rods could be controlled through the synthetic conditions. The color and resistivity of the composites varied with the loading density of ATO nanoparticles. Investigations of the interfacial binding between ATO layer and rod surface indicated that surface characteristics could facilitate the deposition of various metal oxides nanoparticles. XPS analysis demonstrated that the entrance of Sb5+ into SnO2 crystallite led to the improvement of conductivity and the color change of the composites. The formation mechanism for SK composites was also discussed.

  7. Theoretical prediction of thermodynamic activities of liquid Au-Sn-X (X=Bi, Sb, Zn) solder systems

    Energy Technology Data Exchange (ETDEWEB)

    Awe, O.E., E-mail: draweoe2004@yahoo.com [Department of Physics, University of Ibadan, Ibadan (Nigeria); Department of Physics and Engineering Physics, Obafemi Awolowo University, Ile-Ife (Nigeria); Oshakuade, O.M. [Department of Physics, University of Ibadan, Ibadan (Nigeria)

    2017-02-15

    Molecular interaction volume model has been theoretically used to predict the thermodynamic activities of tin in Au-Sn-Bi and Au-Sn-Sb and the thermodynamic activity of zinc in Au-Sn-Zn at experimental temperatures 800 K, 873 K and 973 K, respectively. On the premise of agreement between the predicted and experimental values, we predicted the activities of the remaining two components in each of the three systems. This prediction was extended from three cross-sections to five cross-sections, and to temperature range 400–600 K, relevant for applications. Iso-activities were plotted. Results show that addition of tin reduces the tendency for chemical short range order in both Au-Sb and Au-Zn systems, while addition of gold and bismuth, respectively, reduce the tendency for chemical short range order in Sn-Sb and Au-Sn systems. Also, we found that, in the desired high-temperature region for applications, while a combination of chemical order and miscibility of components exist in both Au-Sn-Bi and Au-Sn-Zn systems, only chemical order exist in the Au-Sn-Sb system. Results, further show that increase in temperature reduces the phase separation tendency in Au-Sn-Bi system.

  8. Structural, optical and electrical properties of porous silicon impregnated with SnO{sub 2}:Sb

    Energy Technology Data Exchange (ETDEWEB)

    Elhouichet, H.; Moadhen, A.; Oueslati, M. [Equipe de Spectroscopie Raman, Faculte des Sciences de Tunis, 2092 Elmanar, Tunis (Tunisia); Romdhane, S.; Bouchriha, H. [Unite Photonique, Polymeres et Dispositifs Optoelectroniques, Faculte des Sciences de Tunis, 2092 Elmanar, Tunis (Tunisia); Roger, J.A. [Laboratoire de Physique de la Matiere Condensee et Nanostructures, UMR CNRS 5586, Universite Claude Bernard, Lyon 1 (France)

    2005-06-01

    The incorporation of antimony doped tin oxide (SnO{sub 2}:Sb), prepared from the sol gel method, into luminescent porous silicon (PS) layers is investigated. Characterisation of the resulting structures by photoluminescence (PL) is presented. It shows that the recuperated PL signal is important and the solid phase does not degrade the skeleton of PS layer with porosity less than 70%. However, for highly porous layers (80%), it was found that the recuperated PL signal is low and the PS skeleton is strongly degraded. Preliminary characterizations of the electrical properties of the resulting nanocomposite structure are presented. The current - voltage characteristic of the SnO{sub 2}:Sb/PS structure is well fitted at low voltage using the Richardson-Schottky diode equation and taking into account of a series resistance R{sub s}. For voltage above 1 V, we show that traps control transport. Electroluminescence (EL) is observed with a threshold at 6 V. All the parameters of the diode are determined and discussed. A diagram of band energy of SnO{sub 2}:Sb/PS/c-Si is proposed. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  9. Unusual magnetic hysteresis and the weakened transition behavior induced by Sn substitution in Mn{sub 3}SbN

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Ying, E-mail: sunying@buaa.edu.cn [Center for Condensed Matter and Materials Physics, Department of Physics, Beihang University, Beijing 100191 (China); International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, Tsukuba, Ibaraki 305-0044 (Japan); Guo, Yanfeng; Li, Jun; Wang, Xia [Superconducting Properties Unit, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044 (Japan); Tsujimoto, Yoshihiro [Materials Processing Unit, National Institute for Materials Science, Tsukuba, Ibaraki 305-0047 (Japan); Wang, Cong [Center for Condensed Matter and Materials Physics, Department of Physics, Beihang University, Beijing 100191 (China); Feng, Hai L.; Sathish, Clastin I.; Yamaura, Kazunari, E-mail: yamaura.kazunari@nims.go.jp [Superconducting Properties Unit, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044 (Japan); Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo, Hokkaido 060-0810 (Japan); Matsushita, Yoshitaka [Analysis Station, National Institute for Materials Science, Tsukuba, Ibaraki 305-0047 (Japan)

    2014-01-28

    Substitution of Sb with Sn was achieved in ferrimagnetic antiperovskite Mn{sub 3}SbN. The experimental results indicate that with an increase in Sn concentration, the magnetization continuously decreases and the crystal structure of Mn{sub 3}Sb{sub 1-x}Sn{sub x}N changes from tetragonal to cubic phase at around x of 0.8. In the doping series, step-like anomaly in the isothermal magnetization was found and this behavior was highlighted at x = 0.4. The anomaly could be attributed to the magnetic frustration, resulting from competition between the multiple spin configurations in the antiperovskite lattice. Meantime, H{sub c} of 18 kOe was observed at x = 0.3, which is probably the highest among those of manganese antiperovskite materials reported so far. With increasing Sn content, the abrupt change of resistivity and the sharp peak of heat capacity in Mn{sub 3}SbN were gradually weakened. The crystal structure refinements indicate the weakened change at the magnetic transition is close related to the change of c/a ratio variation from tetragonal to cubic with Sn content. The results derived from this study indicate that the behavior of Mn{sub 3}Sb{sub 1-x}Sn{sub x}N could potentially enhance its scientific and technical applications, such as spin torque transfer and hard magnets.

  10. Multilayer SnSb4-SbSe Thin Films for Phase Change Materials Possessing Ultrafast Phase Change Speed and Enhanced Stability.

    Science.gov (United States)

    Liu, Ruirui; Zhou, Xiao; Zhai, Jiwei; Song, Jun; Wu, Pengzhi; Lai, Tianshu; Song, Sannian; Song, Zhitang

    2017-08-16

    A multilayer thin film, comprising two different phase change material (PCM) components alternatively deposited, provides an effective means to tune and leverage good properties of its components, promising a new route toward high-performance PCMs. The present study systematically investigated the SnSb4-SbSe multilayer thin film as a potential PCM, combining experiments and first-principles calculations, and demonstrated that these multilayer thin films exhibit good electrical resistivity, robust thermal stability, and superior phase change speed. In particular, the potential operating temperature for 10 years is shown to be 122.0 °C and the phase change speed reaches 5 ns in the device test. The good thermal stability of the multilayer thin film is shown to come from the formation of the Sb2Se3 phase, whereas the fast phase change speed can be attributed to the formation of vacancies and a SbSe metastable phase. It is also demonstrated that the SbSe metastable phase contributes to further enhancing the electrical resistivity of the crystalline state and the thermal stability of the amorphous state, being vital to determining the properties of the multilayer SnSb4-SbSe thin film.

  11. Enhancing electrocatalytic performance of Sb-doped SnO ₂ electrode by compositing nitrogen-doped graphene nanosheets.

    Science.gov (United States)

    Duan, Tigang; Wen, Qing; Chen, Ye; Zhou, Yiding; Duan, Ying

    2014-09-15

    An efficient Ti/Sb-SnO2 electrode modified with nitrogen-doped graphene nanosheets (NGNS) was successfully fabricated by the sol-gel and dip coating method. Compared with Ti/Sb-SnO2 electrode, the NGNS-modified electrode possesses smaller unite crystalline volume (71.11Å(3) vs. 71.32Å(3)), smaller electrical resistivity (13Ωm vs. 34Ωm), and lower charge transfer resistance (10.91Ω vs. 21.01Ω). The accelerated lifetime of Ti/Sb-SnO2-NGNS electrode is prolonged significantly, which is 4.45 times as long as that of Ti/Sb-SnO2 electrode. The results of X-ray photoelectron spectroscopy measurement and voltammetric charge analysis indicate that introducing NGNS into the active coating can increase more reaction active sites to enhance the electrocatalytic efficiency. The electrochemical dye decolorization analysis demonstrates that Ti/Sb-SnO2-NGNS presents efficient electrocatalytic performance for methylene blue and orange II decolorization. And its pseudo-first order kinetic rate constants for methylene blue and orange II decolorization are 36.6 and 44.0 min(-1), respectively, which are 6.0 and 7.1 times as efficient as those of Ti/Sb-SnO2, respectively. Considering the significant electrocatalytic activity and low resistivity of Ti/Sb-SnO2-NGNS electrode, the cost of wastewater treatment can be expected to be reduced obviously and the application prospect is broad. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Electronic structure of InTe, SnAs and PbSb: Valence-skip compound or not?

    Energy Technology Data Exchange (ETDEWEB)

    Hase, Izumi, E-mail: i.hase@aist.go.jp [National Institute of Advanced Industrial Science and Technology, Tsukuba Central 2, 1-1-1 Umezono, Tsukuba 305-8568 (Japan); Yasutomi, Kouki [Graduate School of Pure and Applied Science, Univ. of Tsukuba, Tsukuba, 305-8571 (Japan); Yanagisawa, Takashi; Odagiri, Kousuke [National Institute of Advanced Industrial Science and Technology, Tsukuba Central 2, 1-1-1 Umezono, Tsukuba 305-8568 (Japan); Nishio, Taichiro [Department of Physics, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku, Tokyo 162-8601 (Japan)

    2016-08-15

    Highlights: • We calculated the electronic structure of InTe, SnAs and PbSb from first principles. • Obtained tight-binding parameters of InTe are close to those of BaBiO3, which suggests that their electronic properties are also alike. • InTe is favorable to emerge valence skip, while PbSb is not favorable for it. SnAs is between the two. • Our findings well agree with the experimental results. - Abstract: InTe, SnAs and PbSb formally have unusual valence states, In{sup 2+}, Sn{sup 3+} and Pb{sup 3+}. All of them have B1 crystal structure at some pressure range. They are candidates of the valence-skip compound, which may have negative effective Coulomb interaction U{sub eff} < 0. Negative-U Hubbard model is known to show charge-density wave or superconductivity in some parameter region. In fact, SnAs becomes superconducting at ambient pressure. InTe has a kind of charge-density wave at ambient pressure, and it becomes superconducting at high pressure. We investigated their electronic structures by ab-initio calculations, and calculated the number of s-electrons at the cation site. We found that InTe is favorable to emerge valence skip, while PbSb is not favorable for valence skip. SnAs is between these two. These findings well agree with the experimental results.

  13. Unusual magnetic hysteresis and the weakened transition behavior induced by Sn substitution in Mn3SbN

    Science.gov (United States)

    Sun, Ying; Guo, Yanfeng; Tsujimoto, Yoshihiro; Wang, Cong; Li, Jun; Wang, Xia; Feng, Hai L.; Sathish, Clastin I.; Matsushita, Yoshitaka; Yamaura, Kazunari

    2014-01-01

    Substitution of Sb with Sn was achieved in ferrimagnetic antiperovskite Mn3SbN. The experimental results indicate that with an increase in Sn concentration, the magnetization continuously decreases and the crystal structure of Mn3Sb1-xSnxN changes from tetragonal to cubic phase at around x of 0.8. In the doping series, step-like anomaly in the isothermal magnetization was found and this behavior was highlighted at x = 0.4. The anomaly could be attributed to the magnetic frustration, resulting from competition between the multiple spin configurations in the antiperovskite lattice. Meantime, Hc of 18 kOe was observed at x = 0.3, which is probably the highest among those of manganese antiperovskite materials reported so far. With increasing Sn content, the abrupt change of resistivity and the sharp peak of heat capacity in Mn3SbN were gradually weakened. The crystal structure refinements indicate the weakened change at the magnetic transition is close related to the change of c/a ratio variation from tetragonal to cubic with Sn content. The results derived from this study indicate that the behavior of Mn3Sb1-xSnxN could potentially enhance its scientific and technical applications, such as spin torque transfer and hard magnets.

  14. Superlattice-like SnSb{sub 4}/Ga{sub 3}Sb{sub 7} thin films for ultrafast switching phase-change memory application

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Yifeng [Tongji University, Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, Functional Materials Research Laboratory, School of Materials Science and Engineering, Shanghai (China); Jiangsu University of Technology, School of Mathematics and Physics, Changzhou (China); He, Zifang; Zhai, Jiwei [Tongji University, Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, Functional Materials Research Laboratory, School of Materials Science and Engineering, Shanghai (China); Wu, Pengzhi; Lai, Tianshu [Sun Yat-Sen University, State Key Laboratory of Optoelectronic Materials and Technology, Department of Physics, Guangzhou (China); Song, Sannian; Song, Zhitang [Chinese Academy of Sciences, State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Micro-system and Information Technology, Shanghai (China)

    2015-11-15

    The carrier concentration of Sb-rich phase SnSb{sub 4}, Ga{sub 3}Sb{sub 7} and superlattice-like [SnSb{sub 4}(3.5 nm)/Ga{sub 3}Sb{sub 7}(4 nm)]{sub 7} (SLL-7) thin films as a function of annealing temperature was investigated to explain the reason of resistance change. The activation energy for crystallization was calculated with a Kissinger equation to estimate the thermal stability. In order to illuminate the transition mechanisms, the crystallization kinetics of SLL-7 were explored by using Johnson-Mehl-Avrami theory. The obtained values of Avrami indexes indicate that a one-dimensional growth-dominated mechanism is responsible for the set transition of SLL-7 thin film. X-ray diffractometer and Raman scattering spectra were recorded to investigate the change of crystalline structure. The measurement of atomic force microscopy indicated that SLL-7 thin film has a good smooth surface. A picosecond laser pump-probe system was used to test and verify phase-change speed of the SLL-7 thin film. (orig.)

  15. Possible half-metallicity and variable range hopping transport in Sb-substituted Fe2TiSn Heusler alloys

    Science.gov (United States)

    Chaudhuri, S.; Bhobe, P. A.; Nigam, A. K.

    2018-01-01

    The investigation of the magnetotransport properties on Fe2 TiSn1-x Sb x with 0 ≤slant x ≤slant 0.6 are presented in this paper. The substitution of Sb in place of Sn decreases the anti-site disorder as evident from x-ray diffraction patterns as well as from transport properties measurement. The much-disputed upturn in low temperature electrical resistivity of Fe2 TiSn has been demonstrated to be a result of weak localization induced by anti-site disorder. With increased Sb substitution (⩾25%) the metallic transport behavior of Fe2 TiSn changes to semiconductor-like. At low temperature, carrier transport in such compositions occurs via the variable range hopping mechanism. Moreover, a systematic increase in the anomalous Hall voltage is observed with increasing Sb-content, attributable to a side jump or Berry phase curvature effect. Electrical resistivity in the entire temperature regime hints towards half metallicity of the system. Our ab initio electronic structure calculations using generalised gradient approximation formalism further supports the results of our magnetotransport study.

  16. Nanostructured 3D-porous graphene hydrogel based Ti/Sb-SnO2-Gr electrode with enhanced electrocatalytic activity.

    Science.gov (United States)

    Asim, Sumreen; Zhu, Yunqing; Rana, Masud; Yin, Jiao; Shah, Muhammad Wajid; Li, Yingxuan; Wang, Chuanyi

    2017-02-01

    Nanostructured highly porous 3D-Ti/Sb-SnO2-Gr electrode, based on 3D porous graphene hydrogel was fabricated via a fast-evaporation technique through layer by layer (LBL) deposition. The 3D pores are uniformly distributed on the high fidelity of substrate with pore sizes of 7-12 nm, as confirmed by SEM analysis. Compared to Ti/Sb-SnO2 electrode, the fabricated 3D porous electrode possesses high oxygen evolution potential (2.40 V), smaller charge transfer resistance (29.40 Ω cm(-2)), higher porosity (0.90), enhanced roughness factor (181), and larger voltammetric charge value (57.4 mC cm(-2)). Electrocatalytic oxidation of Rhodamine B (RhB) was employed to evaluate the efficiency of the fabricated 3D-Ti/Sb-SnO2-Gr anode. The results show that the electrochemical reaction follows pseudo first order kinetics with rate constant (k) value of 4.93 × 10(-2) min(-1), which is about 3.91 times higher compared to flat Ti/Sb-SnO2. The fabricated electrode demonstrates better stability and low specific energy consumption signifying its potential usage in electrocatalysis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Synthesis of SnTe/AgSbSe2 nanocomposite as a promising lead-free thermoelectric material

    Directory of Open Access Journals (Sweden)

    Jun He

    2016-06-01

    Full Text Available A series of SnTe-AgSbSe2 composites were synthesized by a zone-melting method. The nanostructure of the composites was determined by the high resolution transmission electron microscope. The results show that the lattice thermal conductivity is decreased to ∼0.6 W/m·K at 820 K due to the intense scattering of phonon. Also, the carrier concentration increases with AgSbSe2 amounts, and a large effective mass of ∼ 4m0 at room temperature appears at a high carrier concentration of ∼2 × 1021/cm3. A relatively high thermoelectric figure of merit ZT of 0.92 at 820 K is obtained by composition optimization. It is indicated that the SnTe-AgSbSe2 composite should be a promising thermoelectric material.

  18. A quantum chemical analysis of Zn and Sb doping and co-doping in SnO2

    Directory of Open Access Journals (Sweden)

    Luis Villamagua

    2017-10-01

    Full Text Available This work presents a quantum chemical study of Zn and Sb doping and co-doping in SnO2 carried out by a DFT+U method. The analysis has been developed by introducing three different modifications in the otherwise pure SnO2 system. In the first place, an oxygen vacancy was introduced within the crystal. Following, such a system was doped (separately by Zn or Sb impurities. Finally, the best energetic positions for both Zn and Sb atoms were simultaneously introduced within the lattice. Results of the simulations show that the confined charge that appeared due to the introduction of the oxygen vacancy interacts with the dopants atoms, being this interaction mostly responsible of the observed effects, i.e., EG shrinkage, F-centers formations, and magnetic momentum rise.

  19. Elemental Topological Dirac Semimetal: α-Sn on InSb(111).

    Science.gov (United States)

    Xu, Cai-Zhi; Chan, Yang-Hao; Chen, Yige; Chen, Peng; Wang, Xiaoxiong; Dejoie, Catherine; Wong, Man-Hong; Hlevyack, Joseph Andrew; Ryu, Hyejin; Kee, Hae-Young; Tamura, Nobumichi; Chou, Mei-Yin; Hussain, Zahid; Mo, Sung-Kwan; Chiang, Tai-Chang

    2017-04-07

    Three-dimensional (3D) topological Dirac semimetals (TDSs) are rare but important as a versatile platform for exploring exotic electronic properties and topological phase transitions. A quintessential feature of TDSs is 3D Dirac fermions associated with bulk electronic states near the Fermi level. Using angle-resolved photoemission spectroscopy, we have observed such bulk Dirac cones in epitaxially grown α-Sn films on InSb(111), the first such TDS system realized in an elemental form. First-principles calculations confirm that epitaxial strain is key to the formation of the TDS phase. A phase diagram is established that connects the 3D TDS phase through a singular point of a zero-gap semimetal phase to a topological insulator phase. The nature of the Dirac cone crosses over from 3D to 2D as the film thickness is reduced.

  20. Low Temperature Solution-Processed Sb:SnO2 Nanocrystals for Efficient Planar Perovskite Solar Cells.

    Science.gov (United States)

    Bai, Yang; Fang, Yanjun; Deng, Yehao; Wang, Qi; Zhao, Jingjing; Zheng, Xiaopeng; Zhang, Yang; Huang, Jinsong

    2016-09-22

    Inorganic metal oxide electron-transport layers (ETLs) have the potential to yield perovskite solar cells with improved stability, but generally need high temperature to form conductive and defect-less forms, which is not compatible with the fabrication of flexible and tandem solar cells. Here, we demonstrate a facile strategy for developing efficient inorganic ETLs by doping SnO2 nanocrystals (NCs) with a small amount of Sb using a low-temperature solution-processed method. The electrical conductivity was remarkably enhanced by Sb-doping, which increased the carrier concentration in Sb:SnO2 NCs. Moreover, the upward shift of the Fermi level owing to doping results in improved energy level alignment, which led to reduced charge recombination, and thus longer electron recombination lifetime and improved open-circuit voltage (VOC ). Therefore, Sb-doping of SnO2 significantly enhanced the photovoltaic performance of planar perovskite devices by increasing the fill factor and VOC , and reducing photocurrent hysteresis, extending the potential application of low-temperature-processed ETLs in future flexible and tandem solar cells. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. One-pot chemical route for morphology-controllable fabrication of Sn-Sb micro/nano-structures: Advanced anode materials for lithium and sodium storage

    Science.gov (United States)

    Yi, Zheng; Han, Qigang; Geng, Di; Wu, Yaoming; Cheng, Yong; Wang, Limin

    2017-02-01

    A series of morphology/component-controllable Sn-Sb micro/nano-structures are fabricated by a one-pot replacement reaction technique employing metallic Sn as both template and reducing agent. Typically, nanoscaled Sn as template and ethyl alcohol as solvent give the hollow structure, while micron-sized Sn as precursor and ethylene glycol as solvent produce the dendritic product. Other mixed structures are also obtained by this one-pot route. As anode materials for lithium-ion batteries, the hollow or dendritic Sn-Sb materials exhibit higher discharge capacities compared with the corresponding Sb samples as well as the Sn templates. Especially, for the Sn-Sb hollow spheres, a high discharge capacity of 820.7 mAh g-1 after first cycle and a reversible capacity of 751 mAh g-1 are achieved after 100 cycles at a current density of 100 mA g-1. Meanwhile, the hollow Sn-Sb structure delivers a specific capacity of 451.3 mA h g-1 at 500 mA g-1 after 150 cycles when used for sodium ion batteries. The superior electrochemical performance that are higher than many reported results can be attributed to the special morphology and structure, which can shorten the transportation distance of lithium/sodium ion and provide extra free space to buffer the volume expansion during the lithium/sodium insertion/extraction.

  2. Thermodynamic study of solid solutions in the SnTe-AgSbTe2 system by means of EMF with solid electrolyte Ag4RbI5

    Science.gov (United States)

    Mashadieva, L. F.; Yusibov, Yu. A.; Kevser, Dzh.; Babanly, M. B.

    2017-09-01

    The results from studying the SnTe-AgSbTe2 system by means of EMF with the solid electrolyte Ag4RbI5 in the temperature range of 300-430 K are presented. The formation of a wide (≥80 mol % of AgSbTe2) region of solid solutions based on SnTe is confirmed. Partial thermodynamic functions Δ G̅, Δ H̅, and Δ S̅ of silver in alloys are calculated from the equations for the EMF temperature dependences. Based on the literature data regarding solid-phase equilibria in the Ag2Te-SnTe-Sb2Te3-Te system, potential-determining reactions are identified that allow us to calculate the standard thermodynamic formation functions and standard entropies of solid solutions (2SnTe) x (AgSbTe2)1- x ( x = 0.2, 0.4, 0.6, 0.8, and 0.9).

  3. Solution route synthesis of InSb, Cu{sub 6}Sn{sub 5} and Cu{sub 2}Sb electrodes for lithium batteries

    Energy Technology Data Exchange (ETDEWEB)

    Sarakonsri, T.; Hackney, S.A. [Department of Metallurgical and Materials Engineering, Michigan Technological University, Houghton, MI 49931 (United States); Johnson, C.S.; Thackeray, M.M. [Electrochemical Technology and Basic Sciences Program, Chemical Engineering Division, Argonne National Laboratory, Argonne, IL 60439 (United States)

    2006-02-28

    A solution method was used to prepare InSb, Cu{sub 6}Sn{sub 5} and Cu{sub 2}Sb intermetallic compounds that are of interest as negative electrode materials for lithium batteries. The compounds were synthesized by the reduction of dissolved transition metal- and metalloid salts with fine Zn powder. Heterogeneous redox reactions at the surface of the Zn particles resulted in fern-like dendritic structures with high surface areas. Powder X-ray diffraction and lattice imaging by transmission electron microscopy showed that the intermetallic products were highly crystalline with preferred crystallographic orientations. Mild heat-treatment of the products under argon improved their phase purity. Electrodes prepared by this method exhibited a large irreversible capacity loss on the first charge/discharge cycle. Cu{sub 2}Sb electrodes showed the greatest cycling stability; after the initial cycle, they delivered more than 230mAhg{sup -1} when cycled between 1.2 and 0.0V versus metallic lithium, consistent with previously reported data for ball-milled Cu{sub 2}Sb electrodes. (author)

  4. The thermoelectric properties of CoSb3 compound doped with Te and Sn synthesized at different pressure

    Science.gov (United States)

    Jiang, Yiping; Jia, Xiaopeng; Ma, Hongan

    2017-10-01

    The skutterudite CoSb2.75Te0.20Sn0.05 compound was synthesized successfully by high pressure and high temperature (HPHT) method using Co, Sb, Te and Sn powder as raw materials. The effects of pressure on its structure and the thermoelectric properties are investigated systematically from 300 K to 800 K. The electrical resistivity and the absolute value of the Seebeck coefficient for the sample increases with rising synthetic pressure. The thermal conductivity of the sample decreases with synthetic pressure and temperature rising in the range of 300-800 K. In this study, the maximum dimensionless figure of merit (ZT) value of 1.17 has been achieved at 793 K, 3 GPa for this thermoelectric material.

  5. Analytisch-chemische aspecten van de bepaling van As, Ca, Cd, Sb, Sn, Pb, Zn in MVS-filterdestruaten met ICP-MS

    NARCIS (Netherlands)

    Velde-Koerts T van der; Lesquillier AI; Ritsema R; LAC

    1995-01-01

    In dit onderzoek werd een ICP-MS-methode ontwikkeld voor de bepaling van Ca, Zn, As, Cd, Sb, Sn en Pb in filterdestruaten. De onderste analysegrens is 30 ng/l Sb, 60 ng/l Cd, 200 ng/l As, 300 ng/l Sn, 400 ng/l Pb, 4 mug/l Zn en 20 mug/l Ca ; de precisie is beter dan 7% RSD voor Ca, 4% RSD voor

  6. Co(x)Ni(4-x)Sb(12-y)Sn(y) Ternary Skutterudites: Processing and Thermoelectric Properties

    Science.gov (United States)

    Mackey, Jon; Sehirlioglu, Alp; Dynys, Fred

    2014-01-01

    Skutterudites have proven to be a useful thermoelectric system as a result of their high figure of merit, favorable mechanical properties, and good thermal stability. Binary skutterudites have received the majority of interest in recent years, as a result of successful double and triple filling schemes. Ternary skutterudites, such as Ni4Sb7Sn5, also demonstrate good thermoelectric performance, with high power factor and low thermal conductivity. Ternary skutterudites, as contrasted to binary systems, provide more possibility for tuning electronic structure as substitutions can be studied on three elements. The Co(x)Ni(4-x)Sb(12-y)Sn(y) system has been investigated as both a p- and n-type thermoelectric material, stable up to 200 C. The system is processed through a combination of solidification, mechanical alloying, and hot pressing steps. Rietveld structure refinement has revealed an interesting occupancy of Sn on both the 24g Wyckoff position with Sb as well as the 2a position as a rattler. In addition to thermoelectric properties, detailed processing routes have been investigated on the system.

  7. Heavy fermion behaviour in the high pressure structure of CeSb{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Fedoseev, Vitaly; Feng, Zhuo; Zou, Yang; Grosche, F. Malte [Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE (United Kingdom); Giles, Terence; Niklowitz, Philipp [Department of Physics, Royal Holloway, University of London, Egham TW20 0EX (United Kingdom); Wilhelm, Heribert [Beamline I15, Diamond Light Source, Didcot OX11 0DE (United Kingdom); Lampronti, Giulio [Department of Earth Sciences, University of Cambridge, Cambridge CB2 3EQ (United Kingdom)

    2015-07-01

    The Kondo lattice system CeSb{sub 2} crystallises in the orthorhombic SmSb{sub 2} structure and exhibits a series of magnetic phase transitions at low temperature. It has been reported to become ferromagnetic below 15 K, with the ordered moment oriented within the basal plane, and to undergo two further transitions at 9K and 12K. These transition are suppressed above a hydrostatic pressure p{sub c} ≅ 16 kbar. We present high pressure transport and x-ray diffraction results, which examine the high pressure state of CeSb{sub 2}. Our findings suggest that CeSb{sub 2} undergoes a drastic structural change at p{sub c} into a new and now fully resolved crystal structure. Whereas in the low pressure structure, CeSb{sub 2} is a local moment magnet, in the high pressure structure it exhibits transport properties characteristic of a heavy fermion material with a low Kondo temperature scale of the order of 10 K.

  8. Crystal structure of Pb 2SbS 2I 3, and re-examination of the crystal chemistry within the group of (Pb/Sn/Sb) chalcogeno-iodides

    Science.gov (United States)

    Doussier, Charlotte; Moëlo, Yves; Léone, Philippe; Meerschaut, Alain; Evain, Michel

    2007-09-01

    The crystal structure of Pb 2SbS 2I 3 was solved at room temperature and 100 K. At 293 K it crystallizes in the orthorhombic system, space group Cmcm (No. 63), with unit cell parameters a = 4.3262(9), b = 14.181(3), c = 16.556(3) Å, V = 1017.7(4) Å 3, Z = 4. The structure is disordered, and combines a split Pb site (s.o.f. = 0.50) with one mixed (Pb,Sb) site with Pb and Sb in two distinct sub-positions. At 100 K, it is monoclinic, space group P2 1/ c, with unit cell parameters a = 7.3629(6), b = 16.466(3), c = 8.5939(7) Å, β = 107.14(2)°, V = 995.6(2) Å 3, Z = 4. The structure is now fully ordered, without mixed sites. On the basis of bond valence calculations, new cation distributions are proposed for published structures of the Sn isotypes, Sn 2SbS 2I 3 and Sn 2SbSe 2I 3. A re-examination of the crystal structures of various (Pb/Sn/Sb) chalcogeno-iodides is presented according to modular analysis. All these structures can be described according to three types of 1D modules, (Pb/Sn)I 4, (Sn) 2I 4 and (Pb/Sn/Sb) 4(S/Se) 2I 4. Generally each type of 1D module gives one type of slab, and the final structure corresponds to a specific stacking of two or three among these slabs. A new structural model is proposed for "α-Sn 2SI 2", which would have the non-stoichiometric composition (Sn 5.42□ 0.58)S 2(I 6.87□ 0.12), ideally Sn 27S 10I 34, with probably a narrow solid solution field on the SnS-SnI 2 joint.

  9. Study of structural and morphological properties of thermally evaporated Sn{sub 2}Sb{sub 6}S{sub 11} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Ben Mehrez, N., E-mail: najia.benmehrez@gmail.com [Université Tunis El Manar, Laboratoire de Photovoltaïque et Matériaux Semi-conducteurs, ENIT, BP 37, Le belvédère, 1002 Tunis (Tunisia); Khemiri, N. [Université Tunis El Manar, Laboratoire de Photovoltaïque et Matériaux Semi-conducteurs, ENIT, BP 37, Le belvédère, 1002 Tunis (Tunisia); Kanzari, M. [Université Tunis El Manar, Laboratoire de Photovoltaïque et Matériaux Semi-conducteurs, ENIT, BP 37, Le belvédère, 1002 Tunis (Tunisia); Institut Préparatoire aux Etudes d’Ingénieurs de Tunis Montfleury, Université de Tunis (Tunisia)

    2016-10-01

    In this study, we report the structural and morphological properties of the new material Sn{sub 2}Sb{sub 6}S{sub 11} thin films prepared on glass substrates by vacuum thermal evaporation at various substrate temperatures (30, 60, 100, 140, 180 and 200 °C). Sn{sub 2}Sb{sub 6}S{sub 11} ingot was synthesized by the horizontal Bridgman technique. The structural properties of Sn{sub 2}Sb{sub 6}S{sub 11} powder were studied by X-ray diffraction (XRD), transmission electron microscopy (TEM) and Raman spectroscopy. The films were characterized for their structural properties by using XRD. All films were polycrystalline in nature. The variations of the structural parameters of the films with the substrate temperature were investigated. The results show that the crystallite sizes increase as the substrate temperature increases. The morphological properties of the films were analyzed by atomic force microscopy (AFM). The roughness and the topography of the surface of the films strongly depend on the substrate temperature. - Highlights: • Sn{sub 2}Sb{sub 6}S{sub 11} powder was successfully synthesized by the horizontal Bridgman technique. • Sn{sub 2}Sb{sub 6}S{sub 11} films were grown by thermal evaporation at different substrate temperatures. • Structural properties of Sn{sub 2}Sb{sub 6}S{sub 11} powder were investigated. • The effect of the substrate temperature on structural and morphological of Sn{sub 2}Sb{sub 6}S{sub 11} films properties was studied.

  10. Filled Co (sub X) Ni (sub 4-x) Sb (sub 12-y) Sn (sub Y) Skutterudites: Processing and Thermoelectric Properties

    Science.gov (United States)

    Mackey, Jon; Sehirlioglu, Alp; Dynys, Fred

    2015-01-01

    Skutterudites have proven to be a useful thermoelectric system as a result of their enhanced figure of merit (ZT1), cheap material cost, favorable mechanical properties, and good thermal stability. The majority of skutterudite interest in recent years has been focused on binary skutterudites like CoSb3 or CoAs3. Binary skutterudites are often double and triple filled, with a range of elements from the lanthanide series, in order to reduce the lattice component of thermal conductivity. Ternary and quaternary skutterudites, such as Co4Ge6Se6 or Ni4Sb8Sn4, provide additional paths to tune the electronic structure. The thermal conductivity can further be improved in these complex skutterudites by the introduction of fillers. The Co (sub X) Ni (sub 4-x) Sb (sub 12-y) Sn (sub Y) system has been investigated as both a p- and n-type thermoelectric material, and is stable up to 200 degrees Centigrade. Yb, Ce, and Dy fillers have been introduced into the skutterudite to study the influence of both the type and the quantity of fillers on processing conditions and thermoelectric properties. The system was processed through a multi-step technique that includes solidification, mechano-chemical alloying, and hot pressing which will be discussed along with thermoelectric transport properties.

  11. Semiconducting Ba 3 Sn 3 Sb 4 and Metallic Ba 7–x Sn 11 Sb 15–y ( x = 0.4, y = 0.6) Zintl Phases

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Haijie [Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States; Materials; Narayan, Awadhesh [Department of Physics, University of Illinois at Urbana−Champaign, Champaign, Illinois 61801, United States; Stoumpos, Constantinos C. [Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States; Zhao, Jing [Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States; Han, Fei [Materials; Chung, Duck Young [Materials; Wagner, Lucas K. [Department of Physics, University of Illinois at Urbana−Champaign, Champaign, Illinois 61801, United States; Kwok, Wai-Kwong [Materials; Kanatzidis, Mercouri G. [Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States; Materials

    2017-11-08

    We report the discovery of two ternary Zintl phases Ba3Sn3Sb4 and Ba7-xSn11Sb15-y, (x = 0.4, y = 0.6). Ba3Sn3Sb4 adopts the monoclinic space group P21/c with a = 14.669(3) Å, b = 6.9649(14) Å, c = 13.629(3) Å, and β = 104.98(3)°. It features a unique corrugated two-dimensional (2D) structure consisting of [Sn3Sb4]6- layers extending along the ab plane with Ba2+ atoms sandwiched between them. The non-stoichiometric Ba6.6Sn11Sb14.4 has a complex one-dimensional (1D) structure adopting the orthorhombic space group Pnma, with unit cell parameters a = 37.964(8) Å, b = 4.4090(9) Å and c = 24.682(5) Å. It consists of large double Sn-Sb ribbons separated by Ba2+ atoms. Ba3Sn3Sb4 is an n-type semiconductor which has a narrow energy gap of ~0.18 eV and a room temperature carrier concentration of ~4.2 × 1018 cm-3. Ba6.6Sn11Sb14.4 is determined to be a metal with electrons being the dominant carriers.

  12. NEUTRON DECAY FROM THE ISOBARIC ANALOG STATE IN SB-120 POPULATED IN SN-120(HE-3,T)SB-120 AT E(HE-3)=200 MEV, THETA=0-DEGREES

    NARCIS (Netherlands)

    ROBERTS, DA; ASHKTORAB, K; BECCHETTI, FD; JANECKE, J; HARAKEH, MN; VANDERWERF, SY; BERG, GPA; FOSTER, CC; LISANTTI, JE; RINCKEL, T; STEPHENSON, EJ; WELLS, SP; NADASEN, A; SHAHEEN, S

    The Sn-120(He-3,t)Sb-120 charge-exchange reaction has been investigated at E(He-3) = 200 MeV and theta approximate to 0 degrees to study neutron decay from the isobaric analog state at E(x)=10.20 MeV in Sb-120. The low-energy neutrons (average energy similar to 0.85 MeV) were detected in coincidence

  13. Limits of carrier mobility in Sb-doped SnO{sub 2} conducting films deposited by reactive sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Bissig, B., E-mail: Benjamin.bissig@empa.ch; Jäger, T.; Tiwari, A. N.; Romanyuk, Y. E. [Laboratory for Thin Films and Photovoltaics, Empa, Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600 Dübendorf (Switzerland); Ding, L. [Photovoltaics and Thin Film Electronics Laboratory, Ecole Polytechnique Fédérale Lausanne (EPFL), Institute of Microengineering (IMT), Rue de la Maladière 71b, 2002 Neuchâtel (Switzerland)

    2015-06-01

    Electron transport in Sb-doped SnO{sub 2} (ATO) films is studied to unveil the limited carrier mobility observed in sputtered films as compared to other deposition methods. Transparent and conductive ATO layers are deposited from metallic tin targets alloyed with antimony in oxygen atmosphere optimized for reactive sputtering. The carrier mobility decreases from 24 cm{sup 2} V{sup −1} s{sup −1} to 6 cm{sup 2} V{sup −1} s{sup −1} when increasing the doping level from 0 to 7 at. %, and the lowest resistivity of 1.8 × 10{sup −3} Ω cm corresponding to the mobility of 12 cm{sup 2} V{sup −1} s{sup −1} which is obtained for the 3 at. % Sb-doped ATO. Temperature-dependent Hall effect measurements and near-infrared reflectance measurements reveal that the carrier mobility in sputtered ATO is limited by ingrain scattering. In contrast, the mobility of unintentionally doped SnO{sub 2} films is determined mostly by the grain boundary scattering. Both limitations should arise from the sputtering process itself, which suffers from the high-energy-ion bombardment and yields polycrystalline films with small grain size.

  14. Limits of carrier mobility in Sb-doped SnO2 conducting films deposited by reactive sputtering

    Directory of Open Access Journals (Sweden)

    B. Bissig

    2015-06-01

    Full Text Available Electron transport in Sb-doped SnO2 (ATO films is studied to unveil the limited carrier mobility observed in sputtered films as compared to other deposition methods. Transparent and conductive ATO layers are deposited from metallic tin targets alloyed with antimony in oxygen atmosphere optimized for reactive sputtering. The carrier mobility decreases from 24 cm2 V−1 s−1 to 6 cm2 V−1 s−1 when increasing the doping level from 0 to 7 at. %, and the lowest resistivity of 1.8 × 10−3 Ω cm corresponding to the mobility of 12 cm2 V−1 s−1 which is obtained for the 3 at. % Sb-doped ATO. Temperature-dependent Hall effect measurements and near-infrared reflectance measurements reveal that the carrier mobility in sputtered ATO is limited by ingrain scattering. In contrast, the mobility of unintentionally doped SnO2 films is determined mostly by the grain boundary scattering. Both limitations should arise from the sputtering process itself, which suffers from the high-energy-ion bombardment and yields polycrystalline films with small grain size.

  15. Electronic and Optical Properties of Ca3MN (M = Ge, Sn, Pb, P, As, Sb and Bi) Antiperovskite Compounds

    Science.gov (United States)

    Iqbal, Samad; Murtaza, G.; Khenata, R.; Mahmood, Asif; Yar, Abdullah; Muzammil, M.; Khan, Matiullah

    2016-08-01

    The electronic and optical properties of cubic antiperovskites Ca3MN (M = Ge, Sn, Pb, P, As, Sb and Bi) were investigated by applying the full potential linearized augmented plane wave plus local orbitals (FP-LAPW + lo) scheme based on density functional theory. Different exchange correlation potentials were adopted for the calculations. The results of band structure and density of states show that, by changing the central anion of Ca3MN, the nature of the materials change from metallic (Ca3GeN, Ca3SnN, Ca3PbN) to semiconducting with small band gaps (Ca3SbN and Ca3BiN) to insulating (Ca3PN and Ca3AsN). The optical properties such as dielectric function, absorption coefficient, optical conductivity, reflectivity and refractive indices have also been calculated. The results reveal that all the studied compounds are optically active in the visible and ultraviolet energy regions, and therefore can be effectively utilized for optoelectronic devices.

  16. Microstructure and electrical properties in SnO{sub 2} ceramics with sequential addition of Co, Sb and Ca

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar-Martinez, J A [Instituto de MinerIa, Universidad Tecnologica de la Mixteca, Carretera a Acatlima Km. 2.5, Huajuapan de Leon, Oaxaca 69000 (Mexico); Hernandez, M B [Instituto de Diseno, Universidad Tecnologica de la Mixteca, Carretera a Acatlima Km. 2.5, Huajuapan de Leon, Oaxaca 69000 (Mexico); Glot, A B [Division de Posgrado, Universidad Tecnologica de la Mixteca, Carretera a Acatlima Km. 2.5, Huajuapan de Leon, Oaxaca 69000 (Mexico); Pech-Canul, M I [Cinvestav Saltillo, Carr. Saltillo-Mty Km 13 Apdo., Saltillo Coahuila 25000 (Mexico)

    2007-11-21

    The effect of sequential additions of Co{sub 3}O{sub 4}, Sb{sub 2}O{sub 5} and CaCO{sub 3} on the microstructure and electrical behaviour of SnO{sub 2}-based ceramics was investigated. Although without conferring varistor properties, Co{sub 3}O{sub 4} additions promote densification in the material. Successive addition of Sb{sub 2}O{sub 5} provides the sample varistor properties but with low nonlinearity coefficient ({alpha} = 5.7) and high electric field (E{sub 1} = 2022 V cm{sup -1}) at current density 10{sup -3} A cm{sup -3}. Moreover, antimony oxide addition degrades the microstructure condition by inducing porosity. Subsequent addition of CaCO{sub 3} promotes densification and grain growth. However, it does not lead to the increase in the nonlinearity coefficient. It only lowers the electric field, thus making the material suitable for lower voltage applications. Observed significant increase in the relative dielectric permittivity up to a factor of about 60 and 200 in the cases of antimony or antimony and calcium addition to SnO{sub 2}-Co{sub 3}O{sub 4} (accompanied by the appearance of varistor effect) is due to the formation of barrier depletion layers at grain boundaries.

  17. Room temperature synthesis of crystalline Sb2S3 for SnO2 ...

    Indian Academy of Sciences (India)

    2S3-sensitized SnO2 photoanode and polysulphide electrolyte. ... Physics, Cummins College of Engineering, Pune 411 052, India; Advanced Physics Laboratory, Department of Physics, Savitribai Phule Pune University, Pune 411 007, India ...

  18. Effect of Ni and Au ion irradiations on structural and optical properties of nanocrystalline Sb-doped SnO{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Mir, Feroz A. [University of Kashmir, University Science Instrumentation Centre, Srinagar, J and K (India); Batoo, Khalid Mujasam [King Saud University, King Abdullah Institute for Nanotechnology, Riyadh (Saudi Arabia)

    2016-04-15

    The effect of swift heavy ion irradiations on the structural and optical properties of 6 % Sb-doped SnO{sub 2} thin films deposited on quartz substrate by electron beam evaporation technique is presented. Two ion species Ni and Au with energy 120 MeV and fluence of 1 x 10{sup 13} ion/cm{sup 2} were used. These films were characterized by X-ray diffraction, atomic force microscope, UV-visible and micro-Raman spectroscopy. From structural analysis, these films exhibit tetragonal rutile structure and retain it even after irradiation. The ion irradiations have shown improvement in the structural properties, such as increase in grain size and decrease in the lattice strain. Raman study also indicates enhancement in quality of crystal structure after irradiations. The grain growth after ion interaction is also observed by atomic force microscope study. Further, a variation in optical band gap and reduction in disorder is observed after irradiation. Other parameters such as Urbach tails energy and steepness parameter are obtained from optical data. The overall observed physical properties show a significant improvement after irradiation. A good correspondence between structures with its various properties can be seen. (orig.)

  19. Bubble assisted synthesis of Sn-Sb-Cu alloy hollow nanostructures and their improved lithium storage properties

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Rong; Huang, Jing; Zhao, Wei; Zhang, Xuanzhou; Zheng, Jie [Beijing National Laboratory for Molecular Sciences (BNLMS), The State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); Lai, Wenzhong [Beijing National Laboratory for Molecular Sciences (BNLMS), The State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); Department of Chemistry and Biology Engineering, Sanming University, Fujian 365004 (China); Li, Xingguo [Beijing National Laboratory for Molecular Sciences (BNLMS), The State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871 (China); College of Engineering, Peking University, Beijing 100871 (China)

    2010-10-01

    Hollow nanospheres of Sn-Sb-Cu alloy composites have been successfully synthesized via co-reduction of metal chlorides in aqueous alkaline solution without using any surfactants or solid templates. A bubble assisted growth mechanism is proposed to account for the formation of the hollow nanostructures. The concentration of the reactants kinetically controls the nucleation rate of the alloy nuclei, making for the formation of the hollow nanospheres. Compared with the alloy nanoparticles, the hollow spheres exhibit relatively high electrochemical capacity and good cyclic retention when used as anode materials for lithium-ion batteries. The bubble assisted synthesis method can be readily explored for fabricating hollow nanostructure of other alloy system for functional material applications. (author)

  20. Sb doping effects and oxygen adsorption in SnO2 thin films deposited via sol-gel

    Directory of Open Access Journals (Sweden)

    Viviany Geraldo

    2003-12-01

    Full Text Available Transparent electrically conducting antimony-doped SnO2 thin films have been prepared by sol-gel dip-coating process from colloidal aqueous suspension. The effect of doping content on the structural, optical and electrical properties is analyzed. Results from infrared optical transmission and reflection have shown that the higher the Sb concentration the lower the transmission intensity and the higher the reflection signal. Absorption intensity increases as well. Results of X-ray reflectometry and electron microscopy have shown that the density of films fired at 400 °C after each dip is higher than that of multi-dipped films prepared with a single annealing. Both the electrical characteristics in the dark and the increase in conductivity as function of illumination through different filters, at 190 K, evidence that the transport properties of these films are dominated by the presence of defects, including the trapping at grain boundary due to excess of oxygen.

  1. Effect of different sound atmospheres on SnO2:Sb thin films prepared by dip coating technique

    Science.gov (United States)

    Kocyigit, Adem; Ozturk, Erhan; Ejderha, Kadir; Turgut, Guven

    2017-11-01

    Different sound atmosphere effects were investigated on SnO2:Sb thin films, which were deposited with dip coating technique. Two sound atmospheres were used in this study; one of them was nay sound atmosphere for soft sound, another was metallic sound for hard sound. X-ray diffraction (XRD) graphs have indicated that the films have different orientations and structural parameters in quiet room, metallic and soft sound atmospheres. It could be seen from UV-Vis spectrometer measurements that films have different band gaps and optical transmittances with changing sound atmospheres. Scanning electron microscope (SEM) and AFM images of the films have been pointed out that surfaces of films have been affected with changing sound atmospheres. The electrical measurements have shown that films have different I-V plots and different sheet resistances with changing sound atmospheres. These sound effects may be used to manage atoms in nano dimensions.

  2. First-principles study of new series of quaternary Heusler alloys CsSrCZ (Z=Si, Ge, Sn, P, As, and Sb)

    Energy Technology Data Exchange (ETDEWEB)

    Bouabça, A. [Condensed Matter and Sustainable Development Laboratory (LMCDD), University of Sidi Bel-Abbes, Sidi Bel-Abbes 22000 (Algeria); Rozale, H., E-mail: hrozale@yahoo.fr [Condensed Matter and Sustainable Development Laboratory (LMCDD), University of Sidi Bel-Abbes, Sidi Bel-Abbes 22000 (Algeria); Amar, A. [Condensed Matter and Sustainable Development Laboratory (LMCDD), University of Sidi Bel-Abbes, Sidi Bel-Abbes 22000 (Algeria); Wang, X.T. [School of Physics and Electronic Engineering, Chongqing Normal University, Chongqing 400044 (China); Sayade, A. [UCCS, CNRS-UMR 8181, Université d’Artois, Faculté des Sciences Jean Perrin, Rue Jean Souvraz, SP 18, 62307 Lens Cedex (France); Chahed, A. [Condensed Matter and Sustainable Development Laboratory (LMCDD), University of Sidi Bel-Abbes, Sidi Bel-Abbes 22000 (Algeria)

    2016-12-01

    The structural, electronic, magnetic, and thermal properties of new quaternary Heusler alloys CsSrCZ (Z=Si, Ge, Sn, P, As, and Sb) were investigated using the full-potential linearized augmented plane wave (FPLAPW) within the generalized gradient approximation (GGA) and GGA plus modified Becke and Johnson as the exchange correlation. The results showed that all Heusler compounds were stable in Type (I) structure. The CsSrCZ (Z=Si, Ge, Sn) compounds had a nearly HM characteristic, and CsSrCZ (Z=P, As, Sb) compounds were true half-metallic (HM) ferromagnets. The strong spin polarization of p orbital for C, Si, Ge, Sn, P, As, and Sb atoms is found to be the origin of ferromagnetic. The half-metallicity is preserved up to a lattice contraction of 3.45%, 1.69%, 1.69%, 7.16%, 7.16%, and 11.2% for all six quaternary Heusler compounds. We also investigated the thermal effects using the quasi-harmonic Debye model. - Highlights: • Electronic, magnetic, and thermodynamic properties of CsSrCZ (Z=Si, Ge, Sn, P, As, and Sb) are investigated. • Until now, there have been no reports theoretical and experimental studies on d{sup 0} half-metals with quaternary structures. • The strong spin polarization of p orbital for C, Si, Ge, Sn, P, As, and Sb atoms is found to be the origin of ferromagnetic. • The half-metallicity is preserved up to a lattice contraction.

  3. Effect of an Sb-Doped SnO2 Support on the CO-Tolerance of Pt2Ru3 Nanocatalysts for Residential Fuel Cells

    Directory of Open Access Journals (Sweden)

    Yoshiyuki Ogihara

    2016-09-01

    Full Text Available We prepared monodisperse Pt2Ru3 nanoparticles supported on carbon black and Sb-doped SnO2 (denoted as Pt2Ru3/CB and Pt2Ru3/Sb-SnO2 with identical alloy composition and particle size distribution by the nanocapsule method. The activities for the hydrogen oxidation reaction (HOR of these anode catalysts were examined in H2-saturated 0.1 M HClO4 solution in both the presence and absence of carbon monoxide by use of a channel flow electrode at 70 °C. It was found that the CO-tolerant HOR mass activity at 0.02 V versus a reversible hydrogen electrode (RHE on the Pt2Ru3/Sb-SnO2 electrode was higher than that at the Pt2Ru3/CB electrode in 0.1 M HClO4 solution saturated with 1000 ppm CO (H2-balance. The CO tolerance mechanism of these catalysts was investigated by in situ attenuated total reflection Fourier transform infrared reflection-adsorption spectroscopy (ATR-FTIRAS in 1% CO/H2-saturated 0.1 M HClO4 solution at 60 °C. It was found, for the Pt2Ru3/Sb-SnO2 catalyst, that the band intensity of CO linearly adsorbed (COL at step/edge sites was suppressed, together with a blueshift of the COL peak at terrace sites. On this surface, the HOR active sites were concluded to be more available than those on the CB-supported catalyst surface. The observed changes in the adsorption states of CO can be ascribed to an electronic modification effect by the Sb-SnO2 support.

  4. Thermal Stability and Electrical Transport Properties of Single-Crystalline β-Zn4Sb3 Co-doped by Ga/Sn

    Science.gov (United States)

    Deng, Shuping; Tang, Yu; Li, Decong; Liu, Hongxia; Chen, Zhong; Shen, Lanxian; Deng, Shukang

    2017-12-01

    In this study, Ga/Sn co-doped single-crystal β-Zn4Sb3 were prepared by a Sn-flux method based on stoichiometric ratios of Zn4- x Sb3Ga x Sn3 ( x = 0, 0.25, 0.5, 0.6 and 0.75). The effect of Ga/Sn co-doping on the thermal stability and electrical transport properties of the obtained samples were investigated. All the prepared samples exhibit p-type conduction, and carrier concentration varies from 4.71 × 1019 cm-3 to 10.44 × 1019 cm-3, while carrier mobility changes from 34.2 cm2 V-1 s-1 to 68.9 cm2 V-1 s-1 at room temperature. Structure analysis indicates that all samples are β-Zn4Sb3 with space group R\\bar{3}c. Thermal analysis results show that the Ga/Sn co-doped samples possess an excellent thermal stability. The results of crystal compositions indicate that both Ga and Sn atoms tend to replace Zn atoms, and the electrical transport properties of the samples were optimized by co-doping Ga and Sn. Meanwhile, the calculated values of the carrier effective mass, band gap and relaxation time agree with the result obtained from a band structure calculation. Consequently, the sample with Ga initial content x = 0.5 possesses excellent electrical properties, which obtains a maximal power factor of 1.56 × 10-3 W m-1 K-2 at 450 K.

  5. Conductivity mechanisms in heavy-doped n-ZrNiSn intermetallic semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Fruchart, D. [Laboratoire de Cristallographie, CNRS, BP 166, 38042 Grenoble Cedex 9 (France); Romaka, V.A. [Ya. Pidstryhach Institute of Applied Problems of Mechanics and Mathematics, National Academy of Sciences of Ukraine, 3b Naukova Street, 79060 Lviv (Ukraine) and National University ' Lvivska Politechnika' , Bandera Street 12, 79013 Lviv (Ukraine)]. E-mail: vromaka@polynet.lviv.ua; Stadnyk, Yu.V. [Ivan Franko Lviv National University, Kyryl and Mephodiy Street 6, 79005 Lviv (Ukraine); Romaka, L.P. [Ivan Franko Lviv National University, Kyryl and Mephodiy Street 6, 79005 Lviv (Ukraine); Gorelenko, Yu.K. [Ivan Franko Lviv National University, Kyryl and Mephodiy Street 6, 79005 Lviv (Ukraine); Shelyapina, M.G. [V.A. Fock Institute of Physics, St. Petersburg State University, Ulyanovskaya 1, Petrodvorets, 198504 St. Petersburg (Russian Federation); Chekurin, V.F. [Ya. Pidstryhach Institute of Applied Problems of Mechanics and Mathematics, National Academy of Sciences of Ukraine, 3b Naukova Street, 79060 Lviv (Ukraine)

    2007-07-12

    A high concentration of the acceptor impurities (N {sub A} about of 10{sup 20} cm{sup -3}) influence on the electronic structure, the Fermi level location, electro-conductivity, Seebeck coefficient, and magnetic susceptibility in the n-ZrNiSn intermetallic semiconductors was investigated. An importance of both donor and acceptor impurity bands in the heavy-doped n-ZrNiSn conductivity was determined. A transition of the conductivity from an activated- to the metallic-like type, with acceptor impurities concentration changing, was observed.

  6. Performance PtSnRh electrocatalysts supported on carbon-Sb{sub 2}O{sub 5}.SbO{sub 2} for the electro-oxidation of ethanol, prepared by an alcohol-reduction process; Desempenho de eletrocatalisadores PtSnRh suportados em carbono-Sb{sub 2}O{sub 5}.SnO{sub 2} para a oxidacao eletroquimica do etanol, preparados pelo metodo de reducao por alcool

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Jose Carlos

    2013-07-01

    PtSnRh electrocatalysts supported on carbon-Sb{sub 2}O{sub 5}.SnO{sub 2}, with metal loading of 20 wt%, were prepared by an alcohol-reduction process, using H{sub 2}PtCl{sub 6}.6H{sub 2}O (Aldrich), RhCl{sub 3}.xH{sub 2}O (Aldrich) and SnCl{sub 2}.2H{sub 2}O (Aldrich), as source of metals; Sb{sub 2}O{sub 5}.SnO{sub 2} (ATO) and carbon Vulcan XC72, as support; and ethylene glycol as reducing agent. The electrocatalysts obtained were characterized physically by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The diffractograms showed which PtSnRh/C-ATO electrocatalysts had FCC structure of Pt and Pt alloys, besides several peaks associated with SnO{sub 2} and ATO. The average sizes of crystallites were between 2 and 4 nm. TEM micrographs showed a good distribution of the nanoparticles on the support. The average sizes of particles were between 2 and 3 nm, with good agreement for the average size of the crystallites. The performances of the electrocatalysts were analyzed by electrochemical techniques and in real conditions of operation using single direct ethanol fuel cell. In the chronoamperometry at 50 deg C, the electrocatalysts with carbon (85 wt%) and ATO (15 wt%) support, showed the best activity, and the atomic proportions which achieved the best results were PtSnRh(70:25:05) e (90:05:05). PtSnRh(70:25:05)/85C+15ATO electrocatalysts showed the best performance in a direct ethanol fuel cell. (author)

  7. Enhancement of Ammonia Sensitivity in Swift Heavy Ion Irradiated Nanocrystalline SnO2 Thin Films

    Directory of Open Access Journals (Sweden)

    Sanju Rani

    2008-01-01

    Full Text Available Swift heavy ion irradiation is an effective technique to induce changes in the microstructure and electronic energy levels of materials leading to significant modification of properties. Here we report enhancement of ammonia (NH3 sensitivity of SnO2 thin films subjected to high-energy Ni+ ion irradiation. Sol-gel-derived SnO2 thin films (100 nm thickness were exposed to 75 MeV Ni+ ion irradiation, and the gas response characteristics of irradiated films were studied as a function of ion fluence. The irradiated films showed p-type conductivity with a much higher response to NH3 compared to other gases such as ethanol. The observed enhancement of NH3 sensitivity is discussed in context of ion beam generated electronic states in the SnO2 thin films.

  8. Acid blue 29 decolorization and mineralization by anodic oxidation with a cold gas spray synthesized Sn-Cu-Sb alloy anode.

    Science.gov (United States)

    do Vale-Júnior, Edilson; Dosta, Sergi; Cano, Irene Garcia; Guilemany, Josep Maria; Garcia-Segura, Sergi; Martínez-Huitle, Carlos Alberto

    2016-04-01

    The elevated cost of anodic materials used in the anodic oxidation for water treatment of effluents undermines the real application of these technologies. The study of novel alternative materials more affordable is required. In this work, we report the application of Sn-Cu-Sb alloys as cheap anodic material to decolorize azo dye Acid Blue 29 solutions. These anodes have been synthesized by cold gas spray technologies. Almost complete decolorization and COD abatement were attained after 300 and 600 min of electrochemical treatment, respectively. The influence of several variables such as supporting electrolyte, pH, current density and initial pollutant concentration has been investigated. Furthermore, the release and evolution of by-products was followed by HPLC to better understand the oxidative power of Sn-Cu-Sb electrodes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. The Roles of Alkyl Branches of Ionic Liquid in the Corrosion Resistance of Pb/Sb/Sn Grids Alloy in Lead-Acid Battery

    Directory of Open Access Journals (Sweden)

    Behzad Rezaei

    2011-01-01

    Full Text Available This paper describes the effects of ionic liquids (ILs including mono, bicyclohexyl, and tetrahexyl ammonium hydrogen sulphate on the corrosion behaviour of Pb/Sb/Sn grids alloy of lead-acid battery with Pb, Sb (1.66 wt%, and Sn (0.24 wt%. Electrochemical behaviour has been investigated using Tafel plots and electrochemical impedance spectroscopy with various concentrations of ILs as electrolyte additives in 4.0 mol⋅L-1 sulphuric acid. The obtained results indicated that, by increasing number of alkyl or cycloalkyl branches in ILs, the corrosion rate of the lead alloy decreases, whereas inhibition efficiency shows a reverse effect. In the presence of all ILs in different concentrations, conversion current of PbSO4 to PbO2 (ia and ic increases, while the reversibility, deduced from peak potential differences, decreases. Also, the effect of ILs adsorption model on the corrosion behaviour of electrode was proposed.

  10. Electrochemical treatment of 2, 4-dichlorophenol using a nanostructured 3D-porous Ti/Sb-SnO2-Gr anode: Reaction kinetics, mechanism, and continuous operation.

    Science.gov (United States)

    Asim, Sumreen; Zhu, Yunqing; Batool, Aisha; Hailili, Reshalaiti; Luo, Jianmin; Wang, Yuanhao; Wang, Chuanyi

    2017-10-01

    2, 4-dichlorophenol (2, 4-DCP) is considered to be a highly toxic, mutagenic, and possibly carcinogenic pollutant. This study is focused on the electrochemical oxidation of 2, 4-DCP on nanostructured 3D-porous Ti/Sb-SnO2-Gr anodes, with the aim of presenting a comprehensive elucidation of mineralization process through the investigation of influential kinetics, the reactivity of hydroxyl radical's and analysis of intermediates. High efficiency was achieved at pH of 3 using Na2SO4 electrolytes at a current density of 30 mA cm(-2). Under the optimized conditions, a maximum removal of 2, 4-DCP of up to 99.9% was reached, whereas a TOC removal of 81% was recorded with the lowest ECTOC (0.49 kW h g(-1)) within 40 min of electrolysis. To explore the stability of the 3D-Ti/Sb-SnO2-Gr electrodes, a continuous electrochemical operation was established, and the consistent mineralization results indicated the effectiveness of the 3D-Ti/Sb-SnO2-Gr system concerning its durability and practical utilization. EPR studies demonstrated the abundant generation of OH radicals on 3D-Ti/Sb-SnO2-Gr, resulting in fast recalcitrant pollutant incineration. From dechlorination and the reactivity of the OH radicals, several intermediates including six cyclic byproducts and three aliphatic carboxylic acids were detected, and two possible degradation pathways were proposed that justify the complete mineralization of 2, 4-DCP. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Phase diagrams of novel Tl{sub 4}SnSe{sub 4}–TlSbSe{sub 2}–Tl{sub 2}SnSe{sub 3} quasi-ternary system following DTA and X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Barchiy, I.E.; Tatzkar, A.R. [Department of Chemistry, Uzhgorod National University, Pidgirna St., 46, Uzhgorod 88000 (Ukraine); Fedorchuk, A.O. [Department of Inorganic and Organic Chemistry, Lviv National University of Veterinary Medicine and Biotechnologies, Pekarska St., 50, Lviv 79010 (Ukraine); Plucinski, K., E-mail: kpluc2006@wp.pl [Electronics Department, Military University Technology, Warsaw, Kaliskiego 2, Warsaw 00-908 (Poland)

    2016-06-25

    Phase relation in the Tl{sub 4}SnSe{sub 4}–TlSbSe{sub 2}–Tl{sub 2}SnSe{sub 3} quasiternary system were studied by the DTA and X-ray diffraction in combination with mathematical modeling. The phase diagrams of the Tl{sub 4}SnSe{sub 4}–TlSbSe{sub 2} and Tl{sub 2}SnSe{sub 3}–TlSbSe{sub 2} systems, the perspective views of the phase interaction in the ternary system, the liquidus surface projection, the isothermal section at 423 K were built for the first time. The Tl{sub 4}SnSe{sub 4}–TlSbSe{sub 2}–Tl{sub 2}SnSe{sub 3} system is of the invariant eutectic type and is characterized by the formation of limited solid solutions following initial ternary compounds. New complex compounds are not formed. - Highlights: • Two Tl{sub 4}SnSe{sub 4}–TlSbSe{sub 2},Tl{sub 2}SnSe{sub 3}–TlSbSe{sub 2} systems were explored. • Invariant processes in the ternary system were determined. • New complex compounds were not observed in ternary system.

  12. Spectroscopy of particle-phonon coupled states in $^{133}$Sb by the cluster transfer reaction of $^{132}$Sn on $^{7}$Li

    CERN Multimedia

    We propose to investigate, with MINIBALL coupled to T-REX, the one-valence-proton $^{133}$Sb nucleus by the cluster transfer reaction of $^{132}$Sn on $^{7}$Li. The excited $^{133}$Sb will be populated by transfer of a triton into $^{132}$Sn, followed by the emission of an $\\alpha$-particle (detected in T-REX) and 2 neutrons. The aim of the experiment is to locate states arising from the coupling of the valence proton of $^{133}$Sb to the collective low-lying phonon excitations of $^{132}$Sn (in particular the 3$^−$). According to calculations in the weak-coupling approach, these states lie in the 4$\\, - \\,$5 MeV excitation energy region and in the spin interval 1/2$\\, - \\,$ 19/2, i.e., in the region populated by the cluster transfer reaction. The results will be used to perform advanced tests of different types of nuclear interactions, usually employed in the description of particle-phonon coupled excitations. States arising from couplings of the proton with simpler core excitations, involving few nucleons...

  13. Site preference and electronic structure of Mn2RhZ (Z = Al, Ga, In, Si, Ge, Sn, Sb: a theoretical study

    Directory of Open Access Journals (Sweden)

    Ren Zhi

    2016-06-01

    Full Text Available The electronic structure and magnetism of Mn2RhZ (Z = Al, Ga, In, Si, Ge, Sn, Sb Heusler alloys have been studied by using first-principles calculations. Three half-metallic ferromagnets, namely, Mn2RhAl, Mn2RhGe and Mn2RhSb have been considered. The calculated equilibrium lattice constant increases with increasing atomic number of Z atoms lying in same column of periodic table. The calculated total magnetic moments Mtot are 2 µB/f.u. for Mn2RhAl and Mn2RhGa, 3 µB/f.u. for Mn2RhSi, Mn2RhGe and Mn2RhSn, and 4 µB/f.u. for Mn2RhSb, which agrees with the Slater-Pauling curve quite well. In all these compounds, except for Mn2RhSb, the moments of Mn (A and Mn (B are antiparallel to each other. The total magnetic moments of the three considered half-metals assume integral values in a wide range of equilibrium lattice parameters.

  14. Effect of Sb Segregation on Conductance and Catalytic Activity at Pt/Sb-Doped SnO2 Interface: A Synergetic Computational and Experimental Study

    DEFF Research Database (Denmark)

    Hu, Qiang; Colmenares Rausseo, Luis César; Martinez, Umberto

    2015-01-01

    . The conductivity of ATO was found to increase, to a magnitude close to that of activated carbon, with an increment of Sb concentration before reaching a saturation point around 10%, and then decrease, indicating that Sb enrichment at the ATO surface may not always favor an increment of the electric current......Antimony doped tin dioxide (ATO) is considered a promising support material for Pt-based fuel cell cathodes, displaying enhanced stability over carbon-based supports. In this work, the effect of Sb segregation on the conductance and catalytic activity at Pt/ATO interface was investigated through...

  15. Thermoelectric properties of Sn- and Pb-doped Tl{sub 9}BiTe{sub 6} and Tl{sub 9}SbTe{sub 6}

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Quansheng; Chan, Meghan; Kuropatwa, Bryan A.; Kleinke, Holger, E-mail: kleinke@uwaterloo.ca [Department of Chemistry and Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)

    2014-11-14

    A variety of substitutions in Tl{sub 9}BiTe{sub 6} and Tl{sub 9}SbTe{sub 6} with Sn and Pb, amounting to 14 different samples, were performed by melting the stoichiometric amounts of elements at 923 K, followed by slow cooling. The pulverized powders were sintered using the hot-pressing technique. All samples were of single phase according to the powder X-ray diffraction patterns. Thermoelectric property measurements were performed to investigate the effects of Sn- and Pb-doping on the electrical conductivity, Seebeck coefficient, and thermal conductivity. Increasing the concentration of the dopants caused increases in electrical and thermal conductivity, while decreasing the Seebeck coefficient. Tl{sub 9}Bi{sub 0.90}Pb{sub 0.10}Te{sub 6} and Tl{sub 9}Bi{sub 0.85}Pb{sub 0.15}Te{sub 6} exhibited the highest power factor. The changes in lattice thermal conductivity were minor and did not follow a clear trend. Competitive ZT values were obtained for Tl{sub 9}Bi{sub 0.95}Sn{sub 0.05}Te{sub 6}, Tl{sub 9}Bi{sub 0.95}Pb{sub 0.05}Te{sub 6}, Tl{sub 9}Sb{sub 0.97}Sn{sub 0.03}Te{sub 6}, and Tl{sub 9}Sb{sub 0.95}Pb{sub 0.05}Te{sub 6}, namely 0.95, 0.94, 0.83, and 0.71 around 500 K, respectively. Higher dopant concentrations led to lower ZT values.

  16. Improvement of reliability and power consumption for SnSb{sub 4} phase change film composited with Ga{sub 3}Sb{sub 7} by superlattice-like method

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Yifeng [Functional Materials Research Laboratory, School of Materials Science and Engineering, Tongji University, No. 4800 Caoan Highway, Shanghai 201804 (China); School of Mathematics and Physics, Jiangsu University of Technology, Changzhou 213001 (China); Zhai, Jiwei, E-mail: apzhai@tongji.edu [Functional Materials Research Laboratory, School of Materials Science and Engineering, Tongji University, No. 4800 Caoan Highway, Shanghai 201804 (China); Zeng, Huarong [Key Laboratory of Inorganic Functional Materials and Devices, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Song, Sannian; Song, Zhitang [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Micro-system and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China)

    2015-05-07

    Superlattice-like (SLL) SnSb{sub 4}/Ga{sub 3}Sb{sub 7} (SS/GS) thin films were investigated through in-situ film resistance measurement. The optical band gap was derived from the transmittance spectra by using a UV-visible-NIR (ultraviolet-visible-near infrared) spectrophotometer. Transmission electron microscopy was used to observe the micro-structure before and after annealing. Phase change memory cells based on the SLL [SS(3 nm)/GS(4.5 nm)]{sub 7} thin films were fabricated to test and verify the operation consumption and switching endurance. The scanning thermal microscopy was used to probe the nanoscale thermal property.

  17. High Light Absorption and Charge Separation Efficiency at Low Applied Voltage from Sb-Doped SnO2/BiVO4 Core/Shell Nanorod-Array Photoanodes.

    Science.gov (United States)

    Zhou, Lite; Zhao, Chenqi; Giri, Binod; Allen, Patrick; Xu, Xiaowei; Joshi, Hrushikesh; Fan, Yangyang; Titova, Lyubov V; Rao, Pratap M

    2016-06-08

    BiVO4 has become the top-performing semiconductor among photoanodes for photoelectrochemical water oxidation. However, BiVO4 photoanodes are still limited to a fraction of the theoretically possible photocurrent at low applied voltages because of modest charge transport properties and a trade-off between light absorption and charge separation efficiencies. Here, we investigate photoanodes composed of thin layers of BiVO4 coated onto Sb-doped SnO2 (Sb:SnO2) nanorod-arrays (Sb:SnO2/BiVO4 NRAs) and demonstrate a high value for the product of light absorption and charge separation efficiencies (ηabs × ηsep) of ∼51% at an applied voltage of 0.6 V versus the reversible hydrogen electrode, as determined by integration of the quantum efficiency over the standard AM 1.5G spectrum. To the best of our knowledge, this is one of the highest ηabs × ηsep efficiencies achieved to date at this voltage for nanowire-core/BiVO4-shell photoanodes. Moreover, although WO3 has recently been extensively studied as a core nanowire material for core/shell BiVO4 photoanodes, the Sb:SnO2/BiVO4 NRAs generate larger photocurrents, especially at low applied voltages. In addition, we present control experiments on planar Sb:SnO2/BiVO4 and WO3/BiVO4 heterojunctions, which indicate that Sb:SnO2 is more favorable as a core material. These results indicate that integration of Sb:SnO2 nanorod cores with other successful strategies such as doping and coating with oxygen evolution catalysts can move the performance of BiVO4 and related semiconductors closer to their theoretical potential.

  18. Nano-porosity in GaSb induced by swift heavy ion irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Kluth, P., E-mail: patrick.kluth@anu.edu.au; Schnohr, C. S.; Giulian, R.; Araujo, L. L.; Lei, W.; Rodriguez, M. D.; Afra, B.; Bierschenk, T.; Ridgway, M. C. [Department of Electronic Materials Engineering, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia); Sullivan, J.; Weed, R. [ARC Centre for Antimatter-Matter Studies, AMPL, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia); Li, W.; Ewing, R. C. [Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, Michigan 48109-1005 (United States)

    2014-01-13

    Nano-porous structures form in GaSb after ion irradiation with 185 MeV Au ions. The porous layer formation is governed by the dominant electronic energy loss at this energy regime. The porous layer morphology differs significantly from that previously reported for low-energy, ion-irradiated GaSb. Prior to the onset of porosity, positron annihilation lifetime spectroscopy indicates the formation of small vacancy clusters in single ion impacts, while transmission electron microscopy reveals fragmentation of the GaSb into nanocrystallites embedded in an amorphous matrix. Following this fragmentation process, macroscopic porosity forms, presumably within the amorphous phase.

  19. Data on metal contents (As, Ag, Sr, Sn, Sb, and Mo in sediments and shells of Trachycardium lacunosum in the northern part of the Persian Gulf

    Directory of Open Access Journals (Sweden)

    Vahid Noroozi Karbasdehi

    2016-09-01

    Full Text Available In this data article, by using inductively coupled plasma optical spectrometry (ICP-OES1 Inductively Coupled Plasma Optical Spectrometry., we aimed to (1 determine the concentration levels of As, Ag, Sr, Sn, Sb, and Mo in the sediments and the shells of Trachycardium lacunosum simultaneously in two separated areas (unpolluted and polluted areas (2 comparison between the metal contents of sediments in the unpolluted and polluted areas as well as shells. Analysis of data showed that sediment as well as shell samples in polluted area contained significantly higher concentration levels of all measured metals compared with unpolluted area.

  20. Epitaxial Growth and Electronic Structure of Half Heuslers Co1-xNixTiSb (001), Ni1-xCoxTiSn, and PtLuSb

    Science.gov (United States)

    2016-01-09

    for a sample temperature of 350°C, as measured by a pyrometer . This reconstruction was not previously observed in CoTiSb10, but was confirmed to...determined using XPS in-situ using monochromated Al Kα radiation (hν = 1486.3 eV). This method uses the energy difference of the core level (CL

  1. Ice-core based assessment of historical anthropogenic heavy metal (Cd, Cu, Sb, Zn) emissions in the Soviet Union.

    Science.gov (United States)

    Eichler, Anja; Tobler, Leonhard; Eyrikh, Stella; Malygina, Natalia; Papina, Tatyana; Schwikowski, Margit

    2014-01-01

    The development of strategies and policies aiming at the reduction of environmental exposure to air pollution requires the assessment of historical emissions. Although anthropogenic emissions from the extended territory of the Soviet Union (SU) considerably influenced concentrations of heavy metals in the Northern Hemisphere, Pb is the only metal with long-term historical emission estimates for this region available, whereas for selected other metals only single values exist. Here we present the first study assessing long-term Cd, Cu, Sb, and Zn emissions in the SU during the period 1935-1991 based on ice-core concentration records from Belukha glacier in the Siberian Altai and emission data from 12 regions in the SU for the year 1980. We show that Zn primarily emitted from the Zn production in Ust-Kamenogorsk (East Kazakhstan) dominated the SU heavy metal emission. Cd, Sb, Zn (Cu) emissions increased between 1935 and the 1970s (1980s) due to expanded non-ferrous metal production. Emissions of the four metals in the beginning of the 1990s were as low as in the 1950s, which we attribute to the economic downturn in industry, changes in technology for an increasing metal recovery from ores, the replacement of coal and oil by gas, and air pollution control.

  2. Thermoelectric properties of p-type sb-doped Cu2SnSe3 near room and mid temperature applications

    Science.gov (United States)

    Prasad, K. Shyam; Rao, Ashok; Chauhan, Nagendra S.; Bhardwaj, Ruchi; Vishwakarma, Avinash; Tyagi, Kriti

    2018-02-01

    In this study, we report low and mid temperature range thermoelectric properties of Sb-substituted Cu2SnSe3 compounds. The Cu2Sn1- x Sb x Se3 (0 ≤ x ≤ 0.04) alloys were prepared using conventional solid-state reaction followed by spark plasma sintering. The crystal structure was characterized using XRD and it reveals that all the samples exhibit cubic structure with space group -4/3m. The electrical transport characteristics indicate degenerate semiconducting behavior. Electrical resistivity was found to follow small polaron hopping (SPH) model in the entire temperature range of investigation. The Seebeck coefficient data reveals that the majority of charge carriers are holes and the analysis of Seebeck coefficient data gives negative values of Fermi energy indicating that the Fermi energy is below the edge of valence band. The electronic contribution ( κ e) for total thermal conductivity is found to be less than 1%. The maximum ZT value of 0.64 is observed for the sample with x = 0.03 (at 700 K) which is approximately 2.3 times that of the pristine sample.

  3. Multielemental Determination of As, Bi, Ge, Sb, and Sn in Agricultural Samples Using Hydride Generation Coupled to Microwave-Induced Plasma Optical Emission Spectrometry.

    Science.gov (United States)

    Machado, Raquel C; Amaral, Clarice D B; Nóbrega, Joaquim A; Araujo Nogueira, Ana Rita

    2017-06-14

    A microwave-induced plasma optical emission spectrometer with N2-based plasma was combined with a multimode sample introduction system (MSIS) for hydride generation (HG) and multielemental determination of As, Bi, Ge, Sb, and Sn in samples of forage, bovine liver, powdered milk, agricultural gypsum, rice, and mineral fertilizer, using a single condition of prereduction and reduction. The accuracy of the developed analytical method was evaluated using certified reference materials of water and mineral fertilizer, and recoveries ranged from 95 to 106%. Addition and recovery experiments were carried out, and the recoveries varied from 85 to 117% for all samples evaluated. The limits of detection for As, Bi, Ge, Sb, and Sn were 0.46, 0.09, 0.19, 0.46, and 5.2 μg/L, respectively, for liquid samples, and 0.18, 0.04, 0.08, 0.19, and 2.1 mg/kg, respectively, for solid samples. The method proposed offers a simple, fast, multielemental, and robust alternative for successful determination of all five analytes in agricultural samples with low operational cost without compromising analytical performance.

  4. Structural and spectroscopic ellipsometry studies on vacuum-evaporated Sn{sub 2m−4}Sb{sub 4}S{sub 2m+2} (m = 2.5, 3 and 4) thin films deposited on glass and Si substrates

    Energy Technology Data Exchange (ETDEWEB)

    Abdelkader, D., E-mail: dhaferabdelkader@gmail.com [Laboratoire de Photovoltaïque et Matériaux Semi-conducteurs-ENIT, Université Tunis ElManar, BP37, Lebelvédère, 1002 Tunis (Tunisia); Akkari, F. Chaffar; Khemiri, N. [Laboratoire de Photovoltaïque et Matériaux Semi-conducteurs-ENIT, Université Tunis ElManar, BP37, Lebelvédère, 1002 Tunis (Tunisia); Gallas, B. [Institut des NanoSciences de Paris-CNRS-Université Pierre et Marie Curie, 4 place Jussieu, 75252 Paris Cedex 05 (France); Antoni, F. [ICube-Laboratoire des sciences de l’Ingénieur, de l' Informatique et de l’Imagerie, Université de Strasbourg-CNRS, 23, rue du Loess, 67037 Strasbourg Cedex (France); Kanzari, M. [Laboratoire de Photovoltaïque et Matériaux Semi-conducteurs-ENIT, Université Tunis ElManar, BP37, Lebelvédère, 1002 Tunis (Tunisia); Institut Préparatoire aux Etudes d' Ingénieurs de Tunis-IPEIT, Université de Tunis, 2, Rue Jawaher Lel Nehru, 1089 Montfleury (Tunisia)

    2015-10-15

    Sn{sub 2m−4}Sb{sub 4}S{sub 2m+2} (m = 2.5, 3 and 4) thin films were deposited on glass and Si substrates using vacuum evaporation technique. The structural properties have been investigated by X-ray diffraction (XRD) and Raman spectroscopy. The XRD patterns revealed the polycrystalline nature of the films on substrates even when they are not heated during evaporation process. Raman spectra revealed four main peaks. The main structural units of Sn–Sb–S thin films are tetrahedral [SnS{sub 4}] and pyramidal [SbS{sub 3}]. The cross-section morphology was obtained by scanning electron microscopy (SEM). Spectroscopic ellipsometry (SE) measurements (ψ and Δ) were carried out to study the optical properties of the films. SE measured data were analyzed by considering double layer optical model for all the samples, with the two oscillators Tauc-Lorentz and Gaussian dispersion relations. Surface roughness was taken into consideration as shown in SEM micrographs. From the ellipsometric study, we determined the thicknesses of the modeled layers and their optical parameters (refractive index, absorption coefficient …). All the films exhibit high absorption coefficient α in the visible range (>10{sup 5} cm{sup −1}). The values of the band gap energy E{sub g} of Sn{sub 2m−4}Sb{sub 4}S{sub 2m+2} thin films deposited on glass were 1.52, 1.29 and 1.28 eV, respectively for m = 2.5, 3 and 4. For the samples deposited on silicon, E{sub g}(SnSb{sub 4}S{sub 7}) = 1.29 eV, E{sub g}(SnSb{sub 2}S{sub 4}) = 1.13 eV and E{sub g}(Sn{sub 2}Sb{sub 2}S{sub 5}) = 1.48 eV. - Highlights: • Sn{sub 2m−4}Sb{sub 4}S{sub 2m+2} films were thermally evaporated on glass and Si substrates. • The films have polycrystalline nature without any heat treatment. • [SnS{sub 4}] tetrahedral and [SbS{sub 3}] pyramidal are the main structural units. • Thicknesses and optical parameters were determined by ellipsometric study. • The films exhibit high absorption coefficient α in the visible

  5. Quaternary tin(IV) antimony(III) sulfide decorated with lanthanum(III) ethylenediamine complexes: [La(en)4SbSnS5]2 x 0.5 H2O.

    Science.gov (United States)

    Feng, Mei-Ling; Ye, Dong; Huang, Xiao-Ying

    2009-09-07

    A quaternary tin(IV) antimony(III) sulfide decorated by lanthanum(III) ethylenediamine complexes, namely, [La(en)(4)SbSnS(5)](2) x 0.5 H(2)O (1; en = ethylenediamine), has been solvothermally synthesized and structurally, thermally, and optically characterized. Its structure features an isolated hexanuclear molecule of [La(en)(4)SbSnS(5)](2). The intermolecule hydrogen-bond interactions result in a three-dimensional supramolecular network, which remains intact upon dehydration.

  6. Electrical and optical properties of Sb-doped BaSnO{sub 3} epitaxial films grown by pulsed laser deposition

    Energy Technology Data Exchange (ETDEWEB)

    Liu Qinzhuang; Dai Jianming; Liu Zhongliang; Zhang Xiaobo; Zhu Guangping; Ding Guohua, E-mail: qzliu@mail.ustc.edu.c [Department of Physics, Huaibei Normal University, Huaibei 235000 (China)

    2010-11-17

    In this paper we report the structural, electrical and optical properties of epitaxial Ba(Sb{sub x}Sn{sub 1-x})O{sub 3} (x = 0-0.30) (BSSO) films grown on SrTiO{sub 3}(0 0 1) substrates by the pulsed laser deposition method. The investigation reveals that the transport and optical characteristics of BSSO films depend very sensitively on the Sb-doping content. Temperature-dependent resistivity measurements show that at low Sb contents (x = 0.03, 0.07) the metal-semiconductor transition occurs at 150 K and 80 K, respectively, and the semiconductor behaviour appears in high doped (x = 0.15, 0.30) films. The transmittance decreases significantly from about 80% to nearly zero in the visible region and the optical band gap shifts from 3.48 to 4.0 eV with increasing Sb content in the films. The lowest room-temperature resistivity of 2.43 m{Omega} cm with carrier density and mobility of 1.65 x 10{sup 21} cm{sup -3} and 1.75 cm{sup 2} V{sup -1} s{sup -1} was obtained in the films with doping at x = 0.07. By employing them as bottom electrodes we have fabricated transparent Pb(Zr{sub 0.52}Ti{sub 0.48})O{sub 3} ferroelectric capacitors showing square polarization-electric field hysteresis loops, indicating that these perovskite-type BSSO films at low doping can be potentially used in transparent devices especially based on all-perovskite heterostructures.

  7. The role of specific features of the electronic structure in electrical resistivity of band ferromagnets Co2Fe Z ( Z = Al, Si, Ga, Ge, In, Sn, Sb)

    Science.gov (United States)

    Kourov, N. I.; Marchenkov, V. V.; Perevozchikova, Yu. A.; Weber, H. W.

    2017-05-01

    The electrical resistivity ρ( T) of the band ferromagnets Co2FeZ (where Z = Al, Si, Ga, Ge, In, Sn, and Sb are s- and p-elements of Mendeleev's Periodic Table) has been investigated in the temperature range 4.2 K < T < 1100 K. It has been shown that the dependences ρ( T) of these alloys in a magnetically ordered state at temperatures T < T C are predominantly determined by the specific features of the electronic spectrum in the vicinity of the Fermi level. The processes of charge carrier scattering affect the behavior of the electrical resistivity ρ( T) only in the vicinity of the Curie temperature T C and above, as well as in the low-temperature range (at T ≪ T C).

  8. Electrochemical evaluation of adsorption and oxidation of the carbon monoxide towards ordered intermetallic phases Pt-M (M=Mn, Pb, Sb e Sn); Avaliacao eletroquimica da adsorcao e oxidacao do monoxido de carbono sobre fases intermetalicas ordenadas Pt-M (M=Mn, Pb, Sb e Sn)

    Energy Technology Data Exchange (ETDEWEB)

    Nicolai, A.L.; Miguel-Junior, E.; Silva, R.I.V. da; Angelo, A.C.D. [UNESP, Bauru, SP (Brazil). Depto. de Quimica. Lab. de Eletrocatalise

    2004-07-01

    This paper presents the experimental results obtained from the electrochemical evaluation of Pt ordered intermetallic phases (PtMn, PtPb, PtSb, PtSn) as electrode materials towards the CO oxidation reaction. The intermetallics showed a higher performance than pure Pt in the same experimental conditions. PtSn has presented the highest performance among the evaluated materials. There was not observed a clear relationship between the electrocatalytic activity of the materials and their ability in producing oxygen species at lower anodic potentials, suggesting that surface electronic density and structural characteristics of the electrode surfaces must be the properties to be investigated in order to explain the obtained results. (author)

  9. Microminiature Hall probes based on n-InSb(Sn)/i-GaAs heterostructure for pulsed magnetic field applications up to 52 T

    Energy Technology Data Exchange (ETDEWEB)

    Mironov, O.A.; Myronov, M.; Durov, S.; Drachenko, O.; Leotin, J

    2004-04-30

    Microminiature Hall probes with sensitive area down to 33x115 {mu}m and based on n-InSb/i-GaAs optimized Sn-doped MBE-grown heterostructures are reported. The 'metallurgical' thicknesses of the n-InSb epilayers lie in the range d{sup m}=1.1-10.5 {mu}m giving room-temperature mobilities of (9-15)x10{sup 3} cm{sup 2}/Vs with carrier densities of (0.96-2.56)x10{sup 18} cm{sup -3}. Characterization of the devices was performed by magnetotransport measurements in quasi-static and pulsed magnetic fields. In the temperature range 1.1-300 K and in magnetic fields up to 12 T (static) and up to 52 T (pulsed, {tau}=120 mS), transport measurements yield remarkable linearity of the Hall voltage up to 52 T and sensitivity, as well as demonstrating the high-temperature stability of the Hall voltage, the offset voltage and the device resistivity. No significant effect of the high current up to 150 mA on either the sensitivity or the resistivity is observed.

  10. Microminiature Hall probes based on n-InSb(Sn)/i-GaAs heterostructure for pulsed magnetic field applications up to 52 T

    Science.gov (United States)

    Mironov, O. A.; Myronov, M.; Durov, S.; Drachenko, O.; Leotin, J.

    2004-04-01

    Microminiature Hall probes with sensitive area down to 33×115 μm and based on n-InSb/i-GaAs optimized Sn-doped MBE-grown heterostructures are reported. The “metallurgical” thicknesses of the n-InSb epilayers lie in the range dm=1.1- 10.5 μm giving room-temperature mobilities of (9-15) ×10 3 cm2/ Vs with carrier densities of (0.96-2.56) ×10 18 cm-3. Characterization of the devices was performed by magnetotransport measurements in quasi-static and pulsed magnetic fields. In the temperature range 1.1- 300 K and in magnetic fields up to 12 T (static) and up to 52 T (pulsed, τ=120 mS), transport measurements yield remarkable linearity of the Hall voltage up to 52 T and sensitivity, as well as demonstrating the high-temperature stability of the Hall voltage, the offset voltage and the device resistivity. No significant effect of the high current up to 150 mA on either the sensitivity or the resistivity is observed.

  11. Effect of Ca, Sr and Ba on the structure, morphology and electrical properties of (Co,Sb)-doped SnO{sub 2} varistors

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar-Martínez, J.A., E-mail: josue.aguilarm@uanl.mx [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, Centro de Investigación e Innovación en Ingeniería Aeronáutica (CIIIA), Carretera a Salinas Victoria km. 2.3, C.P. 66600 Apodaca, N.L. (Mexico); Rodríguez, Edén [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, Av. Universidad S/N, Cd. Universitaria, C.P. 66451 San Nicolás de los Garza, N.L. (Mexico); García-Villarreal, S.; Falcon-Franco, L. [Universidad Autónoma de Coahuila, Facultad de Metalurgia, Carr. 57, Km 4.5, C.P. 25710 Monclova, Coah. (Mexico); Hernández, M.B. [Universidad Autónoma de Nuevo León, Facultad de Ingeniería Mecánica y Eléctrica, Av. Universidad S/N, Cd. Universitaria, C.P. 66451 San Nicolás de los Garza, N.L. (Mexico)

    2015-03-01

    In this work, the effect of calcium (Ca), barium (Ba) and strontium (Sr) additions on the microstructure and electrical properties of SnO{sub 2}-Co{sub 3}O{sub 4}-Sb{sub 2}O{sub 5} ceramic varistors was investigated. It was found that the calcium addition promotes densification and grain growth. Ceramics with calcium addition exhibit the lowest electric field at a fixed current density (10{sup −3} A cm{sup −2}). The addition of strontium shows a similar effect on microstructure and current-voltage characteristics. However, barium addition causes porosity increase, grain size reduction, changes in the grain morphology (from approximately equiaxed to elongated grains) and the electric field at a fixed current density showed almost no change. Consequently, Ba-containing SnO{sub 2}-based ceramics cannot be considered as attractive candidates for low-voltage varistors. - Highlights: • The calcium and Strontium addition promotes densification and grain growth. • Barium addition causes porosity increase, grain size reduction and changes in the grain morphology. • Ceramics with calcium addition exhibit the lowest electric field. • Ceramics with calcium addition can be considered as promising materials for low-voltage varistors.

  12. Experimental formation of Pb, Sn, Ge and Sb sulfides, selenides and chlorides in the presence of sal ammoniac: A contribution to the understanding of the mineral formation processes in coal wastes self-burning

    Science.gov (United States)

    Laufek, František; Veselovsky, František; Drábek, Milan; Kříbek, Bohdan; Klementová, Mariana

    2017-04-01

    The formation of sulfides, selenides and chlorides was experimentally studied at 800 or 900°C in the presence of sal ammoniac in a sealed silica glass tube. Synthetic PbS, PbSe, SnS, GeS, SnGeS2, PbSnS3, SnS and Sb2S3 or natural uraninite were used as a starting charge. Depending on the chemical composition of the sulfide/selenide charge, galena, unnamed SnGeS3 phase, herzenbergite, berndite, ottenmannite, stibnite and unnamed SnSb2S4 and Sn2Sb3S6 phases were identified in sublimates, together with cotunnite and an unnamed (NH4)2SnCl6 phase. When natural uraninite in a mixture with sal ammoniac was used as a charge, the reaction product comprised abundant cotunnite and minor challacolloite due to volatilization of radiogenic lead. When sulfur was introduced to the charge with uraninite and sal ammoniac, galena was found in reaction products. The results of our experiments revealed that if sulfide or selenide phases and NH4Cl are placed in a thermal gradient, it is possible to accelerate their mobility through a process of hydrogen chloride vapor transport. Within the transport process, new solid products are either isochemical or non-isochemical. The isochemical composition of resulting phases with charge probably represents simple sublimation of the original solid phase in form of self-vapor. The non-isochemical phases are probably formed due to combination of sublimation and condensation of various gas components including gaseous HCl. The valency change of metals (e.g. Sn2+ to Sn3+) in several reaction products indicates redox reactions in the gas mixture or during the solidification of resulting products. The role of ammoniac is not clear; however, formation of unnamed (NH4)2SnCl6 compound identified in one of our experiment, indicate possible formation of ammonium complexes. In contrast to experiments where sulfides or selenides were used as a part of charge, mobility of uraninite was not proved under experimental conditions employed. It is consistent with an

  13. Influence of Sb substitution on thermal and electrical characteristics of Ge-Sn-Se chalcogenide glass system

    Science.gov (United States)

    Sharma, Surbhi; Sharma, Navjeet; Sarin, Amit

    2017-12-01

    Present research work reports the systematic investigation of thermal and electrical characterizations of Ge20Sn10Se70-xSbx (x = 0, 3, 6, 9, 12, 15) glass system to probe the structural modifications. Bulk samples are prepared using melt quenching technique. Differential scanning calorimetric technique (DSC) is used at the constant heating rate of 100C under nonisothermal conditions. Different kinetic parameters viz. glass transition temperature Tg, Hruby parameter Hr, crystallization temperature Tc, etc., have been calculated. Glasses under study shows good thermal stability, hence, can find practical applications especially in optical fiber technology. Further, in the current study, an attempt has been made to observe the variation in conductivity with respect to the increase in temperature for amorphous Ge20Sn10Se70-xSbx (x = 0, 3, 6, 9, 12, 15) using two probe method and hence the band structure and corresponding conduction mechanism is studied.

  14. Magnetic phase diagram of the heavy fermion superconductor PrOs sub 4 Sb sub 1 sub 2

    CERN Document Server

    Tayama, T; Sugawara, H; Aoki, Y; Sato, H

    2003-01-01

    We investigated the magnetic phase diagram of the first Pr-based heavy fermion superconductor PrOs sub 4 Sb sub 1 sub 2 by means of high-resolution dc magnetization measurements in low temperatures down to 0.06 K. The temperature dependence of the magnetization M(T) at 0.1 kOe exhibits two distinct anomalies at T sub c sub 1 =1.83 K and T sub c sub 2 =1.65 K, in agreement with the specific heat measurements at zero field. Increasing magnetic field H, both T sub c sub 1 (H) and T sub c sub 2 (H) move toward lower temperatures without showing a tendency of intersecting to each other. Above 10 kOe, the transition at T sub c sub 2 (H) appears to merge into a line of the peak effect which is observed near the upper critical field H sub c sub 2 in the isothermal M(H) curves, suggesting a common origin for these two phenomena. The presence of the field-induced ordered phase (called phase A here) is confirmed for three principal directions above 40 kOe, with the anisotropic A-phase transition temperature T sub A :T s...

  15. Preparation of catalysts PtSb{sub 2}O{sub 5}.SnO{sub 2} supported on carbon and ATO using the alcohol reduction method for electrochemical oxidation of ethanol; Preparacao de eletrocatalisadores PtSb{sub 2}O{sub 5}.SnO{sub 2} suportados em carbono e ATO pelo metodo da reducao por alcool para oxidacao eletroquimica do etanol

    Energy Technology Data Exchange (ETDEWEB)

    Ayoub, Jamil Mahmoud Said

    2013-06-01

    Pt Sn/C-ATO electrocatalysts with different Pt:Sn atomic ratios (90:10, 70:30 and 50:50) were prepared in a single step by an alcohol-reduction process using H{sub 2}PtCl{sub 6}.6H{sub 2}O and SnCl{sub 2}.2H{sub 2}O as metal sources and ethylene glycol as solvent and reducing agent and a physical mixture of carbon Vulcan XC72 (85 wt%) and Sb{sub 2}O{sub 5}.SnO{sub 2} (15 wt%) as support (C-ATO). The obtained materials were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The catalytic activity for ethanol electro-oxidation in acid medium was investigated by cyclic voltammetry and chronoamperometry and in single direct ethanol fuel cell (DEFC). XRD analyses showed that Pt(FCC), SnO{sub 2}, carbon and ATO phases coexist in the obtained materials. The electrochemical studies showed that PtSn/C-ATO electrocatalysts were more active for ethanol electro-oxidation than PtSn/C electrocatalyst. The experiments at 100 deg C on a single DEFC showed that the power density of the cell using Pt Sn/C-ATO (90:10) was nearly 100% higher than the one obtained using Pt Sn/C (50:50). FTIR measurements showed that the addition of ATO to Pt Sn/C favors the formation of acetic acid as a product while for PtSn/C acetaldehyde was the principal product formed. (author)

  16. Enhancement of spin polarization via Fermi level tuning in Co{sub 2}MnSn{sub 1−x}Sb{sub x} (x = 0, 0.25. 0.5, 0.75, 1) Heusler alloys

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Mukhtiyar, E-mail: msphysik09@gmail.com; Thakur, Jyoti; Kashyap, Manish K. [Department of Physics, Kurukshetra University, Kurukshetra - 136119, Haryana (India); Saini, Hardev S. [Department of Physics, National Institute of Technology, Kurukshetra - 136119, Haryana (India)

    2014-04-24

    Full potential approach has been employed to tune Fermi level in Co{sub 2}MnSn{sub 1−x}Sb{sub x} (x = 0, 0.25, 0.5, 0.75, 1) Heulser alloys for enhancement of spin polarization and finding signature of half metallicity. Present density functional theory (DFT) based calculation indicates that stoichoimetric Heusler alloy, Co{sub 2}MnSn is not a half-metallic ferromagnet but the doping of Sb in it results in the shifting of E{sup F} in well-defined energy gap which leads the 100% spin polarization in the resultant alloys. The magnetism in present alloys is governed by localized moment on Mn atom mainly. The tuning of half-metallicity using doping can be proved as an ideal technique to search the new materials which can accomplish the need of spintronics.

  17. High-efficient treatment of wastewater contained the carcinogen naphthylamine by electrochemical oxidation with γ-Al2O3 supported MnO2 and Sb-doped SnO2 catalyst.

    Science.gov (United States)

    Chen, Fengtao; Yu, Sanchuan; Dong, Xiaoping; Zhang, Shishen

    2012-08-15

    1-Naphthylamine wastewater causes severe environmental pollution because of its acute toxicity and carcinogenicity in humans, which makes it difficult to reuse by conventional technologies. In this study, we report an investigation of the electrochemical catalytic oxidation of 1-naphthylamine in synthetic wastewater in a 150 mL electrolytic batch reactor with Ti/Sb-SnO(2)/PbO(2) as anode and steel plate as cathode, where the reaction was assisted by MnO(2) and Sn(1-x)Sb(x)O(2) composite materials as the catalyst and γ-Al(2)O(3) as the carrier (MnO(2)-Sn(1-x)Sb(x)O(2)/γ-Al(2)O(3)). The catalyst was synthesized by impregnating process and was characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The effects of pH and current density on the efficiency of the electrochemical degradation process were also studied. It was found that MnO(2)-Sn(1-x)Sb(x)O(2)/γ-Al(2)O(3) exhibited excellent catalytic activity in the electrochemical degradation of 1-naphthylamine wastewater. The results showed that the refractory organics in wastewater can be effectively removed by this process, and a chemical oxygen demand (COD) removal efficiency of 92.2% was obtained in 20 min at pH 7.0 and current density was equal to 50 mA cm(-2). According to the experimental results, a hypothetical mechanism of electrochemical catalytic degradation was also proposed. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Spark plasma-sintered Sn-based intermetallic alloys and their Li-storage studies

    CSIR Research Space (South Africa)

    Nithyadharseni, P

    2016-06-01

    Full Text Available In the present study, SnSb, SnSb/Fe, SnSb/Co, and SnSb/Ni alloy powders processed by co-precipitation were subjected to spark plasma-sintering (SPS) at 400 °C for 5 min. The compacts were structurally and morphologically characterized by X...

  19. Structure and properties of silver doped SnSe{sub 2} and Ge{sub 2}Sb{sub 2}Te{sub 5} thin films prepared by pulsed laser deposition

    Energy Technology Data Exchange (ETDEWEB)

    Popescu, M.; Sava, F.; Lorinczi, A.; Tomescu, A.; Simion, C.; Matei, E. [National Institute R and D of Materials Physics, Atomistilor str. 105 bis, P. O. Box MG. 7, 77125 Bucharest-Magurele-Ilfov (Romania); Velea, A. [National Institute R and D of Materials Physics, Atomistilor str. 105 bis, P. O. Box MG. 7, 77125 Bucharest-Magurele-Ilfov (Romania); Faculty of Physics, University of Bucharest, P.O. Box MG. 5, 77125 Bucharest-Magurele-Ilfov (Romania); Socol, G.; Mihailescu, I.N. [National Institute of Lasers, Plasma and Radiation Physics, P. O. Box MG. 6, 77125 Bucharest-Magurele-Ilfov (Romania); Andonie, A.; Stamatin, I. [Faculty of Physics, University of Bucharest, P.O. Box MG. 5, 77125 Bucharest-Magurele-Ilfov (Romania)

    2010-03-15

    Amorphous thin films of SnSe{sub 2} and Ge{sub 2}Sb{sub 2}Te{sub 5} doped by different amount of silver (0.1, 0.2, 0.5 and 1 Ag atoms per formula unit) have been prepared by pulsed laser deposition (PLD) starting from solid polycrystalline targets. The films were investigated by X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The good gas sensing properties for CO, as well as the sensitivity for CH{sub 4} and NO of the Ag doped SnSe{sub 2} films have been demonstrated in the composition SnSe{sub 2}Ag{sub 0.2}. The structural effect of silver introduced in Ge{sub 2}Sb{sub 2}Te{sub 5} matrix has been investigated. The freshly deposited thin films doped by various amount of Ag develop three phases: an amorphous one, and two crystalline phases consisting of a major fcc cubic phase of AgSbTe{sub 2} and a minor cubic phase of composition Ag{sub 2}Te. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  20. First principles study of (Cd, Hg, In, Tl, Sn, Pb, As, Sb, Bi, Se) modified Pt(111), Pt(100) and Pt(211) electrodes as CO oxidation catalysts

    DEFF Research Database (Denmark)

    Tripkovic, Vladimir

    2015-01-01

    CO oxidation is a prototype reaction for studying oxidation of small organic molecules. Certain adatom modified Pt electrodes have a large promotional effect on CO oxidation. However, the effect is often coverage dependent, and has a limited effect due to short lifetimes of the adatoms. The cover......CO oxidation is a prototype reaction for studying oxidation of small organic molecules. Certain adatom modified Pt electrodes have a large promotional effect on CO oxidation. However, the effect is often coverage dependent, and has a limited effect due to short lifetimes of the adatoms....... The coverage dependence as a function of potential for ten different adatom species (Cd, Hg, In, Tl, Sn, Pb, As, Sb, Bi, Se) on bare and CO saturated Pt(111), Pt(100) and Pt(211) surfaces has been established by means of Density Functional Theory calculations. Most of the adatoms are very stable under standard...... conditions and remain anchored to the surface until high potentials in supporting electrolytes. The stability is contingent on the electrode roughness and reduces in the following order: Pt(211) ≈ Pt(100) > Pt(111), except for Se adatoms, in which case the trend is reversed. The activity for CO oxidation...

  1. High-efficient treatment of wastewater contained the carcinogen naphthylamine by electrochemical oxidation with {gamma}-Al{sub 2}O{sub 3} supported MnO{sub 2} and Sb-doped SnO{sub 2} catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Fengtao, E-mail: cft0923@163.com [Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018 (China); Yu, Sanchuan; Dong, Xiaoping; Zhang, Shishen [Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018 (China)

    2012-08-15

    Highlights: Black-Right-Pointing-Pointer A method for the electrochemical catalytic oxidation of 1-naphthylamine in synthetic wastewater is elucidated. Black-Right-Pointing-Pointer The novel catalyst, Mn-Sb-Sn/{gamma}-Al{sub 2}O{sub 3}, was prepared and characterized. Black-Right-Pointing-Pointer A fairly satisfactory result (92.2% COD removal rate) was achieved in 20 min at pH 7 under mild conditions. Black-Right-Pointing-Pointer The hypothetical mechanism of electrochemical catalytic oxidation degradation was also proposed. - Abstract: 1-Naphthylamine wastewater causes severe environmental pollution because of its acute toxicity and carcinogenicity in humans, which makes it difficult to reuse by conventional technologies. In this study, we report an investigation of the electrochemical catalytic oxidation of 1-naphthylamine in synthetic wastewater in a 150 mL electrolytic batch reactor with Ti/Sb-SnO{sub 2}/PbO{sub 2} as anode and steel plate as cathode, where the reaction was assisted by MnO{sub 2} and Sn{sub 1-x}Sb{sub x}O{sub 2} composite materials as the catalyst and {gamma}-Al{sub 2}O{sub 3} as the carrier (MnO{sub 2}-Sn{sub 1-x}Sb{sub x}O{sub 2}/{gamma}-Al{sub 2}O{sub 3}). The catalyst was synthesized by impregnating process and was characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The effects of pH and current density on the efficiency of the electrochemical degradation process were also studied. It was found that MnO{sub 2}-Sn{sub 1-x}Sb{sub x}O{sub 2}/{gamma}-Al{sub 2}O{sub 3} exhibited excellent catalytic activity in the electrochemical degradation of 1-naphthylamine wastewater. The results showed that the refractory organics in wastewater can be effectively removed by this process, and a chemical oxygen demand (COD) removal efficiency of 92.2% was obtained in 20 min at pH 7.0 and current density was equal to 50 mA cm{sup -2}. According to the experimental results, a hypothetical mechanism of electrochemical catalytic

  2. Evidence for magnetic-field-induced quadrupolar ordering in the heavy-fermion superconductor PrOs sub 4 Sb sub 1 sub 2

    CERN Document Server

    Kohgi, M; Nakajima, M

    2003-01-01

    Neutron diffraction experiments on the heavy-fermion superconductor PrOs sub 4 Sb sub 1 sub 2 revealed that a small antiferromagnetic moment, parallel to [010] (y-direction), is induced in the field-induced phase (H || z). The analysis, based on the GAMMA sub 1 singlet ground state crystal field model, shows that antiferro-order of O sub y sub z -type quadrupole moments of Pr ions is formed in the field-induced phase. This strongly suggests that the crystal field ground-state of Pr ions in PrOs sub 4 Sb sub 1 sub 2 is the GAMMA sub 1 singlet and the quadrupolar ordering is induced due to level crossing with an excited state under a magnetic field. (author)

  3. Distribution of impurity states and charge transport in Zr{sub 0.25}Hf{sub 0.75}Ni{sub 1+x}Sn{sub 1−y}Sb{sub y} nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yuanfeng; Makongo, Julien P.A. [Laboratory for Emerging Energy and Electronic Materials, Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109 (United States); Page, Alexander [Department of Physics, University of Michigan, Ann Arbor, MI 48109 (United States); Sahoo, Pranati [Laboratory for Emerging Energy and Electronic Materials, Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109 (United States); Uher, Ctirad [Department of Physics, University of Michigan, Ann Arbor, MI 48109 (United States); Stokes, Kevin [The Advanced Materials Research Institute, Department of Physics, University of New Orleans, New Orleans, LA 70148 (United States); Poudeu, Pierre F.P., E-mail: ppoudeup@umich.edu [Laboratory for Emerging Energy and Electronic Materials, Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI 48109 (United States)

    2016-02-15

    Energy filtering of charge carriers in a semiconducting matrix using atomically coherent nanostructures can lead to a significant improvement of the thermoelectric figure of merit of the resulting composite. In this work, several half-Heusler/full-Heusler (HH/FH) nanocomposites with general compositions Zr{sub 0.25}Hf{sub 0.75}Ni{sub 1+x}Sn{sub 1−y}Sb{sub y} (0≤x≤0.15 and y=0.005, 0.01 and 0.025) were synthesized in order to investigate the behavior of extrinsic carriers at the HH/FH interfaces. Electronic transport data showed that energy filtering of carriers at the HH/FH interfaces in Zr{sub 0.25}Hf{sub 0.75}Ni{sub 1+x}Sn{sub 1−y}Sb{sub y} samples strongly depends on the doping level (y value) as well as the energy levels occupied by impurity states in the samples. For example, it was found that carrier filtering at HH/FH interfaces is negligible in Zr{sub 0.25}Hf{sub 0.75}Ni{sub 1+x}Sn{sub 1−y}Sb{sub y} (y=0.01 and 0.025) composites where donor states originating from Sb dopant dominate electronic conduction. However, we observed a drastic decrease in the effective carrier density upon introduction of HH/FH interfaces for the mechanically alloyed Zr{sub 0.25}Hf{sub 0.75}Ni{sub 1+x}Sn{sub 0.995}Sb{sub 0.005} samples where donor states from unintentional Fe impurities contribute the largest fraction of conduction electrons. This work demonstrates the ability to synergistically integrate the concepts of doping and energy filtering through nanostructuring for the optimization of electronic transport in semiconductors. - Graphical abstract: Electronic transport in semiconducting half-Heusler (HH) matrices containing full-Heusler (FH) nanoinclusions strongly depends on the energy distribution of impurity states within the HH matrix with respect to the magnitude of the potential energy barrier at the HH/FH interfaces. - Highlights: • Coherent nanostructures enhanced thermoelectric behavior of half-Heusler alloys. • Nanostructures act as energy filter of

  4. Inelastic neutron scattering study on low-energy excitations of the heavy-fermion superconductor PrOs{sub 4}Sb{sub 12}

    Energy Technology Data Exchange (ETDEWEB)

    Kuwahara, K. [Department of Physics, Tokyo Metropolitan University, Tokyo 192-0397 (Japan)]. E-mail: kuwahara@phys.metro-u.ac.jp; Iwasa, K. [Department of Physics, Tohoku University, Sendai 980-8578 (Japan); Kohgi, M. [Department of Physics, Tokyo Metropolitan University, Tokyo 192-0397 (Japan); Kaneko, K. [ASRC, Japan Atomic Energy Research Institute, Ibaraki 319-1195 (Japan); Metoki, N. [Department of Physics, Tohoku University, Sendai 980-8578 (Japan); ASRC, Japan Atomic Energy Research Institute, Ibaraki 319-1195 (Japan); Raymond, S. [CEA-Grenoble, DRFMC/SPSMS, 38054 Grenoble (France); Institut Laue-Langevin, 38042 Grenoble (France); Measson, M.-A. [CEA-Grenoble, DRFMC/SPSMS, 38054 Grenoble (France); Flouquet, J. [CEA-Grenoble, DRFMC/SPSMS, 38054 Grenoble (France); Sugawara, H. [Faculty of Integrated Arts and Sciences, Tokushima University, Tokushima 770-8592 (Japan); Aoki, Y. [Department of Physics, Tokyo Metropolitan University, Tokyo 192-0397 (Japan); Sato, H. [Department of Physics, Tokyo Metropolitan University, Tokyo 192-0397 (Japan)

    2006-11-15

    Low-energy magnetic excitations in single crystals of the heavy-fermion superconductor PrOs{sub 4}Sb{sub 12} have been studied by inelastic neutron scattering. The clear softening of excitations at a wave vector Q=(1,0,0), which is the same as the modulation vector of the field-induced antiferro-quadrupolar ordering, and the intensity analyses of excitations directly evidence that the nonmagnetic quadrupolar fluctuations are dominant in this system. Furthermore, the narrowing of the linewidths of the excitations in the superconducting phase indicates the close connection between the superconductivity and the excitations. The preliminary data under magnetic fields are also presented.

  5. Neutron scattering study on the field-induced antiferro-quadrupolar ordering in the heavy fermion superconductor PrOs{sub 4}Sb{sub 12}

    Energy Technology Data Exchange (ETDEWEB)

    Metoki, N. E-mail: metoki@kotai3.tokai.jaeri.go.jp; Kaneko, K.; Araki, S.; Kohgi, M.; Iwasa, K.; Kuwahara, K.; Bernhoeft, N.; Mignot, J.M.; Gukasov, A.; Sato, H.; Aoki, Y.; Sugawara, H

    2004-05-01

    We found the field-induced antiferro-quadrupole (AFQ) ordering in the Pr-based heavy fermion superconductor PrOs{sub 4}Sb{sub 12} by means of neutron scattering. The field-induced staggered moment and the field dependence of the crystal field excitation spectra can be well understood in terms of the mean field Hamiltonian based on the singlet {gamma}{sub 1} with triplet {gamma}{sub 4} first excited state, where the quadrupolar interaction plays essential role for the AFQ ordering.

  6. Desenvolvimento do pigmento condutor SnO2 -Sb2O3 e sua aplicação em vidrados semicondutores Development of a SnO2 -Sb2O3 conductor pigment and its applications in semiconductor glazes

    Directory of Open Access Journals (Sweden)

    R. Aguiar

    2004-06-01

    Full Text Available Esmaltes semicondutores são utilizados no recobrimento de isoladores elétricos para evitar descargas superficiais nos isoladores, associadas a grandes diferenças de potencial, proporcionando uma melhora no desempenho sob poluição ambiental. Como os vidrados utilizados nas indústrias cerâmicas são isolantes, uma maneira de torná-los semicondutores é adicionando óxidos condutores. Misturou-se ao esmalte porcentagens variadas do pigmento condutor SnO2 dopado com 5% de Sb2O3. O esmalte foi aplicado sobre peças de porcelana a verde e queimado a 1250 ºC. Por microscopia eletrônica de varredura verificou-se que a concentração de pigmento na superfície das amostras é baixa e não influencia a condutividade elétrica. Na fratura, a porcentagem de pigmento ficou próxima de 35%. Assim, a superfície ficou com aspecto visual de ótima qualidade. A resistividade elétrica ocorreu pelo interior do vidrado, obtendo-se valores próximos de 10(4 Ohm.m.Semiconductor glazes are employed on electrical insulators to avoid surface discharge under conditions of intense electric fields, providing better performance in polluted environments. Semiconductor enamels are of great interest for electrical insulator coatings to avoid surface discharges, related to large potential differences. This enhances the performance of the insulator under polluted environments. Glazes used in ceramic industries are not conductive. The addition of conductive oxides to the glaze composition results in a semiconductor enamel. Sb2O3-doped SnO2 was mixed with the enamel in different concentrations. The resulting enamel was applied over green porcelain and fired at 1250 ºC. Scanning electron microscopy characterization was performed and it was verified that the pigment concentration on the surface is low and does not affect the electrical conductivity. The pigment concentration on the fracture surface is approximately 35%. The insulator surface presents a high quality

  7. Evidence for Point Nodes in the Superconducting Gap Function in the Filled Skutterudite Heavy-Fermion Compound PrOs4Sb12: 123Sb-NQR Study under Pressure

    Science.gov (United States)

    Katayama, Kouta; Kawasaki, Shinji; Nishiyama, Masahide; Sugawara, Hitoshi; Kikuchi, Daisuke; Sato, Hideyuki; Zheng, Guo-qing

    2007-02-01

    We report 123Sb nuclear quadrupole resonance (NQR) measurements of the filled skutterudite heavy-fermion superconductor PrOs4Sb12 under high pressures of 1.91 and 2.34 GPa. The temperature dependence of NQR frequency and the spin-lattice relaxation rate 1/T1 indicate that the crystal-electric-field splitting ΔCEF between the ground state Γ1 singlet and the first excited state Γ4(2) triplet decreases with increasing pressure. The 1/T1 below Tc = 1.55 K at P = 1.91 GPa shows a power-law temperature variation and is proportional to T5 at temperatures considerably below Tc, which indicates the existence of point nodes in the superconducting gap function. The data can be well fitted by the gap model Δ(θ) = Δ0\\sinθ with Δ0 = 3.08kBTc. The relation between the superconductivity and the quadrupole fluctuations associated with the Γ4(2) state is discussed.

  8. The effect of the pairing interaction on the energies of isobar analogue resonances in {sup 112-124}Sb and isospin admixture in {sup 100-124}Sn isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Babacan, Tahsin [Department of Physics, Celal Bayar University, Manisa (Turkey); Salamov, Djavad [Department of Physics, Anadolu University, Eskisehir (Turkey); Kuecuekbursa, Atalay [Department of Physics, Dumlupinar University, Kuetahya (Turkey); Babacan, Halil [Department of Physics, Celal Bayar University, Manisa (Turkey); Maras, Ismail [Department of Physics, Celal Bayar University, Manisa (Turkey); Aygoer, Hasan A [Department of Physics, Celal Bayar University, Manisa (Turkey); Uenal, Arslan [Department of Physics, Dumlupinar University, Kuetahya (Turkey)

    2004-06-01

    In the present study, the effect of the pairing interaction and the isovector correlation between nucleons on the properties of the isobar analogue resonances (IAR) in {sup 112-124}Sb isotopes and the isospin admixture in {sup 100-124}Sn isotopes is investigated within the framework of the proton-neutron quasi-particle random phase approximation (pnQRPA). The form of the interaction strength parameter is related to the shell-model potential by restoring the isotopic invariance of the nuclear part of the total Hamiltonian. In this respect, the isospin admixtures in the {sup 100-124}Sn isotopes are calculated, and the dependence of the differential cross section and the volume integral J{sub F} for the Sn({sup 3}He,t)Sb reactions at E({sup 3}He) =200 MeV occurring by the excitation of IAR on mass number A is examined. Our results show that the calculated value for the isospin mixing in the {sup 100}Sn isotope is in good agreement with Colo et al's estimates (4-5%), and the obtained values for the volume integral change within the error range of the value reported by Fujiwara et al (53 {+-} 5 MeV fm{sup 3}). Moreover, it is concluded that although the differential cross section of the isobar analogue resonance for the ({sup 3}He,t) reactions is not sensitive to pairing correlations between nucleons, a considerable effect on the isospin admixtures in N {approx} Z isotopes can be seen with the presence of these correlations.

  9. Experimental study of the excitation functions of deuteron induced reactions on natSn up to 40 MeV

    Science.gov (United States)

    Tárkányi, F.; Ditrói, F.; Hermanne, A.; Takács, S.; Király, B.; Baba, M.; Ignatyuk, A. V.

    2011-02-01

    Using the stacked-foil activation technique, cross-sections of deuteron induced reactions on natural Sn were measured up to 40 MeV. Excitation functions are reported for the product nuclides 111In, 113Sn, 117mSn, 125mSn, 125gSn, 115Sb, 116mSb, 117Sb, 118mSb 120mSb, 122Sb, 124Sb and 125Sb and compared with the earlier published data sets. For all excitation functions comparisons with theoretical calculations using the ALICE-IPPE, EMPIRE, EAF and the TALYS codes were performed.

  10. The Krásná Hora, Milešov, and Příčovy Sb-Au ore deposits, Bohemian Massif: mineralogy, fluid inclusions, and stable isotope constraints on the deposit formation

    Science.gov (United States)

    Němec, Matěj; Zachariáš, Jiří

    2017-04-01

    The Krásná Hora-Milešov and Příčovy districts (Czech Republic) are the unique examples of Sb-Au subtype orogenic gold deposits in the Bohemian Massif. They are represented by quartz-stibnite veins and massive stibnite lenses grading into low-grade, disseminated ores in altered host rocks. Gold postdates the stibnite and is often replaced by aurostibite. The ore zones are hosted by hydrothermally altered dikes of lamprophyres (Krásná Hora-Milešov) or are associated with local strike-slip faults (Příčovy). Formation of Sb-Au deposits probably occurred shortly after the main gold-bearing event (348-338 Ma; Au-only deposits) in the central part of the Bohemian Massif. Fluid inclusion analyses suggest that stibnite precipitated at 250 to 130 °C and gold at 200 to 130 °C from low-salinity aqueous fluids. The main quartz gangue hosting the ore precipitated from the same type of fluid at about 300 °C. Early quartz-arsenopyrite veins are not associated with the Sb-Au deposition and formed from low-salinity, aqueous-carbonic fluid at higher pressure and temperature ( 250 MPa, 400 °C). The estimated oxygen isotope composition of the ore-bearing fluid (4 ± 1‰ SMOW; based on post-ore calcite) suggests its metamorphic or mixed magmatic-metamorphic origin and excludes the involvement of meteoric water. Rapid cooling of warm hydrothermal fluids reacting with "cold" host rock was probably the most important factor in the formation of both stibnite and gold.

  11. The Krásná Hora, Milešov, and Příčovy Sb-Au ore deposits, Bohemian Massif: mineralogy, fluid inclusions, and stable isotope constraints on the deposit formation

    Science.gov (United States)

    Němec, Matěj; Zachariáš, Jiří

    2018-02-01

    The Krásná Hora-Milešov and Příčovy districts (Czech Republic) are the unique examples of Sb-Au subtype orogenic gold deposits in the Bohemian Massif. They are represented by quartz-stibnite veins and massive stibnite lenses grading into low-grade, disseminated ores in altered host rocks. Gold postdates the stibnite and is often replaced by aurostibite. The ore zones are hosted by hydrothermally altered dikes of lamprophyres (Krásná Hora-Milešov) or are associated with local strike-slip faults (Příčovy). Formation of Sb-Au deposits probably occurred shortly after the main gold-bearing event (348-338 Ma; Au-only deposits) in the central part of the Bohemian Massif. Fluid inclusion analyses suggest that stibnite precipitated at 250 to 130 °C and gold at 200 to 130 °C from low-salinity aqueous fluids. The main quartz gangue hosting the ore precipitated from the same type of fluid at about 300 °C. Early quartz-arsenopyrite veins are not associated with the Sb-Au deposition and formed from low-salinity, aqueous-carbonic fluid at higher pressure and temperature ( 250 MPa, 400 °C). The estimated oxygen isotope composition of the ore-bearing fluid (4 ± 1‰ SMOW; based on post-ore calcite) suggests its metamorphic or mixed magmatic-metamorphic origin and excludes the involvement of meteoric water. Rapid cooling of warm hydrothermal fluids reacting with "cold" host rock was probably the most important factor in the formation of both stibnite and gold.

  12. Effect of Cr{sub 2}O{sub 3} on the microstructure and non-ohmic properties of (Co, Sb)-doped SnO{sub 2} varistors

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar M, J. A. [Centro de Investigac ion en Materiales Avanzados, S. C., Alianza Norte No. 202, Parque de Investigacion e Innovacion Tecnologica, Nueva Carretera Aeropuerto Km. 10 Apodaca 66600, Nuevo Leon (Mexico); Pech C, M. I. [IPN, Centro de Investigacion y de Estudios Avanzados, Unidad Saltillo, Carretera Saltillo-Monterrey Km. 13, Saltillo 25900, Coahuila (Mexico); Hernandez, M. B.; Rodriguez, E.; Garcia O, L. [Universidad Autonoma de Nuevo Leon, Facultad de Ingenieria Mecanica y Electrica, San Nicolas de los Garza, Nuevo Leon (Mexico); Glot, A. B., E-mail: josue.aguilar@cimav.edu.mx [Universidad Tecnologica de la Mixteca, Division de Estudios de Posgrado, Carretera Acatlima Km. 2.5, Huajuapan de Leon 69000, Oaxaca (Mexico)

    2013-10-01

    The effect of Cr{sub 2}O{sub 3} addition on the physical characteristics, microstructure, and current-voltage properties of (Co-Sb)-doped SnO{sub 2} varistors was investigated. SnO{sub 2}-Co{sub 3}O{sub 4}-Sb{sub 2}O{sub 5} ceramics with additions of 0.0, 0.03, 0.05 and 0.07 mol % Cr{sub 2}O{sub 3} were sintered at 1350 C under ambient atmosphere and characterized micro structurally and electrically. The characterization by X-ray diffraction and scanning electron microscopy show that the microstructure remains as a single phase material with multimodal size distribution of SnO{sub 2} grains. The greatest effect of Cr{sub 2}O{sub 3} additions is manifested in the electric breakdown field. Additions of high levels (0.07 and 0.05 %) of this oxide promote and increase of approximately 55% in this parameter compared to the Cr{sub 2}O{sub 3}-free sample. Another physical property is affected: the measured density values decreases as the Cr{sub 2}O{sub 3} content increases. A change in the nonlinearity coefficient value is produced only at the highest Cr{sub 2}O{sub 3} content while at intermediate levels there is not change at all. Consequently, when seeking high nonlinearity coefficients, intermediate levels of Cr{sub 2}O{sub 3} are not recommended. (Author)

  13. Spatial distribution of heavy metal contamination in soils near a primitive e-waste recycling site.

    Science.gov (United States)

    Quan, Sheng-Xiang; Yan, Bo; Yang, Fan; Li, Ning; Xiao, Xian-Ming; Fu, Jia-Mo

    2015-01-01

    The total concentrations of 12 heavy metals in surface soils (SS, 0-20 cm), middle soils (MS, 30-50 cm) and deep soils (DS, 60-80 cm) from an acid-leaching area, a deserted paddy field and a deserted area of Guiyu were measured. The results showed that the acid-leaching area was heavily contaminated with heavy metals, especially in SS. The mean concentrations of Ni, Cu, Zn, Cd, Sn, Sb and Pb in SS from the acid-leaching area were 278.4, 684.1, 572.8, 1.36, 3,472, 1,706 and 222.8 mg/kg, respectively. Heavy metal pollution in the deserted paddy field was mainly concentrated in SS and MS. The average values of Sb in SS and MS from the deserted paddy field were 16.3 and 20.2 mg/kg, respectively. However, heavy metal contamination of the deserted area was principally found in the DS. Extremely high concentrations of heavy metals were also observed at some special research sites, further confirming that the level of heavy metal pollution was very serious. The geoaccumulation index (Igeo) values revealed that the acid-leaching area was severely polluted with heavy metals in the order of Sb > Sn > Cu > Cd > Ni > Zn > Pb, while deserted paddy field was contaminated predominately by metals in the order of Sb > Sn > Cu. It was obvious that the concentrations of some uncommon contaminants, such as Sb and Sn, were higher than principal contaminants, such as Ni, Cu, Zn and Pb, suggesting that particular attention should be directed to Sn and Sb contamination in the future research of heavy metals in soils from e-waste-processing areas. Correlation analysis suggested that Li and Be in soils from the acid-leaching area and its surrounding environment might have originated from other industrial activities and from batteries, whereas Ni, Cu, Zn, Cd, Pb, Sn and Sb contamination was most likely caused by uncontrolled electronic waste (e-waste) processing. These results indicate the significant need for optimisation of e-waste-dismantling technologies and remediation of polluted soil

  14. Photoemission of heavy fermion superconductor PrOs{sub 4} Sb{sub 12} and other Pr compounds

    Energy Technology Data Exchange (ETDEWEB)

    Imada, S. [Graduate School of Engineering Science, Osaka University, Toyonaka 560-8531 (Japan)]. E-mail: imada@mp.es.osaka-u.ac.jp; Fukuda, Y. [Graduate School of Engineering Science, Osaka University, Toyonaka 560-8531 (Japan); Yamasaki, A. [Graduate School of Engineering Science, Osaka University, Toyonaka 560-8531 (Japan); Sekiyama, A. [Graduate School of Engineering Science, Osaka University, Toyonaka 560-8531 (Japan); Sugawara, H. [Faculty of Integrated Arts and Sciences, Tokushima University, Tokushima 770-8502 (Japan); Sato, H. [Graduate School of Science, Tokyo Metropolitan University, Hachioji 192-0397 (Japan); Ochiai, A. [Graduate School of Science, Tohoku University, Sendai 980-8578 (Japan); Suga, S. [Graduate School of Engineering Science, Osaka University, Toyonaka 560-8531 (Japan)

    2005-06-15

    PrOs{sub 4} Sb{sub 12} and other Pr compounds have been studied by means of bulk sensitive photoemission. The Pr 4f electronic state was probed by means of the Pr 3d->4f resonant photoemission (RPES). RPES spectrum was found to depend upon the photon energy (h{nu}) especially above the Pr 3d{sub 5/2} peak. It seems that the h{nu} dependence is weak enough before the absorption intensity reaches the half of the peak.

  15. Distribution of heavy metal pollution in sediments from an acid leaching site of e-waste.

    Science.gov (United States)

    Quan, Sheng-Xiang; Yan, Bo; Lei, Chang; Yang, Fan; Li, Ning; Xiao, Xian-Ming; Fu, Jia-Mo

    2014-11-15

    The spatial distribution, bioavailability, potential risks and emission sources of 12 heavy metals in sediments from an acid leaching site of e-waste were investigated. The results showed that the sediments from the acid leaching site were significantly contaminated with Cu, Zn, Cd, Sn, Sb and Pb, especially in the middle sediments (30-50 cm), with average concentrations of 4820, 1260, 10.7, 2660, 5690 and 2570 mg/kg, respectively. Cu, Cd and Pb were mainly present in the non-residual fractions, suggesting that the sediments from the acid leaching site may exert considerable risks. Mn, Ni, Zn, Sn and Sb were predominantly associated with the residual fraction. Despite their low reactivity and bioavailability, uncommon pollutants, such as Sn and Sb, may exert environmental risks due to their extremely elevated total concentrations. All of these results indicate that there is an urgent need to control the sources of heavy metal emission and to remediate contaminated sediments. In addition to Ni, Cu, Zn, Cd and Pb, the sediments from an acid leaching site in Guiyu were heavily polluted with uncommon heavy metal pollutants, such as Sn and Sb. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. $\\gamma$- spectroscopy of n-rich $^{95,96}$Rb nuclei by the incomplete fusion reaction of $^{94}$Kr on $^{7}$Li: Introduction to HIE-ISOLDE studies of n-rich Sb and Tl isotopes with Sn and Hg radioactive beams.

    CERN Document Server

    Fornal, B; Bednarczyk, P; Cieplicka, N; Krolas, W; Maj, A; Leoni, S; Benzoni, G; Blasi, N; Bottoni, S; Bracco, A; Camera, F; Crespi, F; Million, B; Morales, A; Wieland, O; Rusek, K; Lunardi, S; Mengoni, D; Recchia, F; Ur, CA; Valiente-Dobon, J; de France, G; Clement, E; Elseviers, J; Flavigny, F; Huyse, M; Raabe, R; Sambi, S; Van Duppen, P; Sferrazza, M; Simpson, G; Georgiev, G; Sotty, C; Blazhev, A; German, R; Siebeck, B; Seidlitz, M; Reiter, P; Warr, N; Boenig, S; Ilieva, S; Kroell, T; Scheck, M; Thurauf, M; Gernhaeuser, R; Mucher, D; Janssens, R; Carpenter, MP; Zhu, S; Marginean, NM; Balabanski, D; Kowalska, M

    2012-01-01

    $\\gamma$- spectroscopy of n-rich $^{95,96}$Rb nuclei by the incomplete fusion reaction of $^{94}$Kr on $^{7}$Li: Introduction to HIE-ISOLDE studies of n-rich Sb and Tl isotopes with Sn and Hg radioactive beams.

  17. Elastic properties of antiperovskite-type Ni-rich nitrides MNNi{sub 3} (M=Zn, Cd, Mg, Al, Ga, In, Sn, Sb, Pd, Cu, Ag and Pt) as predicted from first-principles calculations

    Energy Technology Data Exchange (ETDEWEB)

    Bannikov, V.V.; Shein, I.R. [Institute of Solid State Chemistry, Ural Branch of the Russian Academy of Sciences, 620990 Ekaterinburg (Russian Federation); Ivanovskii, A.L., E-mail: ivanovskii@ihim.uran.r [Institute of Solid State Chemistry, Ural Branch of the Russian Academy of Sciences, 620990 Ekaterinburg (Russian Federation)

    2010-11-15

    We have performed accurate ab initio total energy calculations using the full-potential linearized augmented plane wave (FP-LAPW) method with the generalized gradient approximation (GGA) for the exchange-correlation potential to systematically investigate elastic properties of 12 synthesized and hypothetical cubic antiperovskite-type Ni-rich nitrides MNNi{sub 3}, where M are Zn, Cd, Mg, Al, Ga, In, Sn, Sb, Pd, Cu, Ag and Pt. As a result, the optimized lattice parameters, independent elastic constants (C{sub ij}), bulk-, shear- and tetragonal shear moduli, Cauchy's pressure and some indexes of elastic anisotropy, as well as the numerical estimations of Young's modulus, Poisson's ratio and Pugh's indicator of brittle/ductile behavior for the corresponding polycrystalline MNNi{sub 3} (in the Voigt-Reuss-Hill approximation) were obtained and analyzed in comparison with the available theoretical and experimental data.

  18. Quench hardening of Sb0.2 Bi1.8Te3, Bi2Te2.8Se0.2 and Sn0.2 Bi1.8Te3 single crystals

    Science.gov (United States)

    Soni, P. H.

    2018-02-01

    The V2-VI3 intermetallics are narrow band gap semiconductors and well known for their thermoelectric properties. They therefore offer a convenient route to tune band gap for manipulating thermoelectric parameters. The V group element Sb can be fruitfully used to substitute Bi in various proportions thus forming a psuedobinary solid solution. The electronic in general and the thermoelectric properties in particular of this psuedobinary have been amply reported. However there are no reports found on mechanical properties. I have used Sb0.2 Bi1.8Te3, Bi2Te2.8Se0.2 and Sn0.2 Bi1.8Te3single crystals grown using Bridgman technique for the quenching treatment followed by hardness testing. Vickers hardness tests were conducted on the cleavage planes of the crystals quenched from various high temperatures and the quench hardenening coefficient values have been determined. The hardness tests were carried out at various applied loads also to explore load dependence of the measured hardness. The results are reported in the paper.

  19. Fractionation of Li, Be, Ga, Nb, Ta, In, Sn, Sb, W and Bi in the peraluminous Early Permian Variscan granites of the Cornubian Batholith: Precursor processes to magmatic-hydrothermal mineralisation

    Science.gov (United States)

    Simons, Beth; Andersen, Jens C. Ø.; Shail, Robin K.; Jenner, Frances E.

    2017-05-01

    The Early Permian Variscan Cornubian Batholith is a peraluminous, composite pluton intruded into Devonian and Carboniferous metamorphosed sedimentary and volcanic rocks. Within the batholith there are: G1 (two-mica), G2 (muscovite), G3 (biotite), G4 (tourmaline) and G5 (topaz) granites. G1-G2 and G3-G4 are derived from greywacke sources and linked through fractionation of assemblages dominated by feldspars and biotite, with minor mantle involvement in G3. G5 formed though flux-induced biotite-dominate melting in the lower crust during granulite facies metamorphism. Fractionation enriched G2 granites in Li (average 315 ppm), Be (12 ppm), Ta (4.4 ppm), In (74 ppb), Sn (18 ppm) and W (12 ppm) relative to crustal abundances and G1 granites. Gallium (24 ppm), Nb (16 ppm) and Bi (0.46 ppm) are not significantly enriched during fractionation, implying they are more compatible in the fractionating assemblage. Sb (0.16 ppm) is depleted in G1-G2 relative to the average upper and lower continental crust. Muscovite, a late-stage magmatic/subsolidus mineral, is the major host of Li, Nb, In, Sn and W in G2 granites. G2 granites are spatially associated with W-Sn greisen mineralisation. Fractionation within the younger G3-G4 granite system enriched Li (average 364 ppm), Ga (28 ppm), In (80 ppb), Sn (14 ppm), Nb (27 ppm), Ta (4.6 ppm), W (6.3 ppm) and Bi (0.61 ppm) in the G4 granites with retention of Be in G3 granites due to partitioning of Be into cordierite during fractionation. The distribution of Nb and Ta is controlled by accessory phases such as rutile within the G4 granites, facilitated by high F and lowering the melt temperature, leading to disseminated Nb and Ta mineralisation. Lithium, In, Sn and W are hosted in biotite micas which may prove favourable for breakdown on ingress of hydrothermal fluids. Higher degrees of scattering on trace element plots may be attributable to fluid-rock interactions or variability within the magma chamber. The G3-G4 system is more boron

  20. The crystal structure of franckeite, Pb21.7Sn9.3Fe4.0Sb8.1S56.9

    DEFF Research Database (Denmark)

    Makovicky, Emil; Petricek, Vaclav; Dusek, Michal

    2011-01-01

    The layer-like crystal structure of franckeite from the mine of San José, Bolivia, exhibits a pronounced one-dimensional transversal wave-like modulation and a non-commensurate layer match in two dimensions. It consists of alternating pseudohexagonal (H) layers and pseudotetragonal (Q) slabs...... and H stacking directions, and the divergence between modulation wave-front and these stacking directions are typical for the composite structures of franckeite and cylindrite. Because of the increased rigidity of the Q component, franckeite usually forms masses of curved crystals rather than...... cylindrical aggregates. The existence of this family depends critically on the radius ratios of the cations involved, especially those involving (Pb2+, Sn2+) and Sn4+. Their replacement by a Pb2+:Bi3+ combination leads to misfit layer structures of a very different type, typified by cannizzarite....

  1. Concentration of heavy metal As, Pb, Mn, Ni, Sn, Zn, Cr, Fe and radon gas in bottom sediment from abandoned tin mines in the Phuket Province

    Directory of Open Access Journals (Sweden)

    Suteerasak, T.

    2006-05-01

    Full Text Available This research is aimed at analyzing the heavy metals: As, Pb, Mn, Ni, Sn, Zn, Cr, Fe, and radon gas emission in bottom sediment from six abandoned tin mines in Phuket Province. Fe, Mn, and Sn were found in higher concentrations (but non-polluting than Cr and Ni. As, Pb, and Zn were polluting at lower levels. The concentration ranges for As, Pb, and Zn were 75.3-169, 98.6-547.5, and 120.4-323.3 mg/kg respectively. The activity of radon gas emission from bottom sediment from an abandoned tin mine in Amphur Muang was in the range of 162-212 Bq/kg., in the Amphur Katoo mine the range was 122-266 Bq/kg. and in the Amphur Talang mine the range was 180-263 Bq/kg. All these sites have higher concentrations of radon gas emissions than other similar sites. The heavy metals and radon gas come from geochemical materials such as soil and granite rock, found around the abandoned tin mines.

  2. Investigations on MnSb and related compounds with b8-type structures

    NARCIS (Netherlands)

    Bouwma, Jakob

    1972-01-01

    This thesis describes investigations on phases with hexagonal B8-type structures in the systems Mn-Sb-Sn, Mn-Sb-Te, Mn-Cr-Sb and Mn-V-Sb. In -chapter 1 some general remarks are made on compounds with B8-type structures. The preparation of the samples, and the X-ray crystallographic investigations

  3. Current-voltage characteristics of SnO{sub 2}-Co{sub 3}O{sub 4}-Cr{sub 2}O{sub 3}-Sb{sub 2}O{sub 5} ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar-Martinez, J A [Centro de Investigacion en Materiales Avanzados, S.C. (CIMAV), Alianza Norte 202, Parque de Investigacion e Innovacion Tecnologica (PIIT), Nueva Carretera Aeropuerto km. 10, Apodaca, Nuevo Leon, CP 66600 (Mexico); Glot, A B [Posgrado, Universidad Tecnologica de la Mixteca, Carretera Acatlima Km. 2.5, Huajuapan de Leon, Oaxaca, CP 69000 (Mexico); Gaponov, A V [Department of Radioelectronics, Dniepropetrovsk National University, Dniepropetrovsk 49050 (Ukraine); Hernandez, M B [Instituto de Mineria, Universidad Tecnologica de la Mixteca, Carretera Acatlima Km. 2.5, Huajuapan de Leon, Oaxaca, CP 69000 (Mexico); Guerrero-Paz, J, E-mail: josue.aguilar@cimav.edu.m [Particulate Materials Lab, Universidad Autonoma del Estado de Hidalgo, Pachuca, CP 42184 (Mexico)

    2009-10-21

    The effect of mechanical treatment in a planetary mill on the microstructure and electrical properties of tin dioxide based varistor ceramics in the system SnO{sub 2}-Co{sub 3}O{sub 4}-Cr{sub 2}O{sub 3}-Sb{sub 2}O{sub 5} sintered in the range 1150-1450 {sup 0}C was studied. The mechanical treatment leads to an increase in shrinkage, decrease in porosity, decrease in sample diameter, change in colour of the sintered samples from grey to black and enhancement of nonlinearity. For the sample sintered at 1350 {sup 0}C the mechanical treatment enhances the nonlinearity coefficient from 11 to 31 and decreases the electric field E{sub 1} (at 10{sup -3} A cm{sup -2}) from 3500 to 2800 V cm{sup -1}. The observed changes in physical properties are explained in terms of an additional size reduction of oxide particles and a better mixing of oxide powder followed by the formation of potential barriers at the grain boundaries throughout the whole sample. In spite of the low porosity, the low-field electrical conductivity of mechanically treated ceramics is significantly increased with the growth of relative humidity. A higher humidity sensitivity is found for mechanically treated ceramics with higher barrier height and higher nonlinearity coefficient.

  4. Heavy Metals (Mg, Mn, Ni and Sn contamination in Soil Samples of Ahvaz II Industrial Estate of Iran in 2013

    Directory of Open Access Journals (Sweden)

    Soheil l Sobhanardakani

    2016-04-01

    Full Text Available Background & Aims of the Study: Due to the rapid industrial development in Khuzestan province of Iran during recent years, this study was performed to analyze the variation of metals concentrations (Mg, Mn, Ni, and Sn in soil samples of Ahvaz II Industrial estate during the spring season of 2013. Materials & Methods: In this experimental study, 27 topsoil samples were collected from nine stations. The intensity of the soil contamination was evaluated, using a contamination factor (Cf and geo-accumulation index (I-geo. Results:  The mean soil concentrations (in mg kg-1 (dry weight were in ranged within 870-1144 (Mg, 188-300 (Mn, 93-199 (Ni and 9-15 (Sn. The data indicated that the I-geo value for all metals falls in class ‘1’. Also the Cf value for Mg and Mn falls in class ‘0’, the Cf value for Sn falls in class ‘1’ and the Cf value for Ni falls in the classes of ‘1’ and ‘2’. The result of the Pearson correlation showed that there were significant positive associations between all metals. Conclusions: According to the results which were achieved by a cluster analysis, there were significant positive associations among all metals based on Pearson correlation coefficient, especially between Ni and Sn; also both of them with Mn. Because the Ni originates from oil sources it can be resulted that Mn and Sn originate from oil sources, too. Therefore, industrial activities and exploitation of oil reservoirs are the main cause of pollution in that area. Also, it can be concluded that, with increasing the distance from the source of pollution, the accumulation of contaminants in the soil samples decreased.

  5. Effect of Th substitution on ferrimagnetic transition in the heavy-electron compound UCu{sub 5}Sn

    Energy Technology Data Exchange (ETDEWEB)

    Troc, Robert E-mail: troc@int.pan.wroc.pl; Tran, Vinh Hung; Andraka, Bohdan; Pietri, Robert; Cichorek, Tomasz

    2001-05-01

    It was found that the ferrimagnetic properties of the solid solutions (U{sub 1-x} Th{sub x})Cu{sub 5}Sn are detected almost up to x congruent with 0.8. Non-Fermi liquid-like behavior with unusual log T dependences of C/T has been observed for all the alloys studied, i.e. not only in nonmagnetic but also in magnetically ordered states. A possible interpretation of these data based on the recent development of unconventional Kondo models is given.

  6. ATONISHING [CO2SO3H]-: CARBONATO AND SULFITO NEW ADDUCTS DERIVING FROM THE INTERACTIONS BETWEEN R4NCO2SO3H (R=Et, Me AND HgX2, SnX4 (X=Cl, Br, SbCl5

    Directory of Open Access Journals (Sweden)

    DINORA DE BARROS

    2013-12-01

    Full Text Available In ethanol, a C-S cleavage occurs in final products on allowing R4NCO2SO3H – R = Me, Et - to react with HgX2, SnX4 (M = Hg, X= Cl, Br, leading to carbonate and sulfite adducts and complexes ,infrared study of which have been carried out, then structures suggested on the basis of spectroscopic data. When (Me4NCO2SO3H is allowed to react with SbCl5, HgX2 (X = Cl, Br, sulfite adducts were obtained, studied by infrared. The suggested structures are discrete, the sulfite anion behaving as a bidentate ligand.

  7. As, Bi, Hg, S, Sb, Sn and Te geochemistry of the J-M Reef, Stillwater Complex, Montana: constraints on the origin of PGE-enriched sulfides in layered intrusions

    Science.gov (United States)

    Zientek, M.L.; Fries, T.L.; Vian, R.W.

    1990-01-01

    The J-M Reef is an interval of disseminated sulfides in the Lower Banded series of the Stillwater Complex that is enriched in the platinum group elements (PGE). Palladium and Pt occur in solid solution in base-metal sulfides and as discrete PGE minerals. PGE minerals include sulfides, tellurides, arsenides, antimonides, bismuthides, and alloys with Fe, Sn, Hg, and Au. Several subpopulations can be delineated based on whole-rock chemical analyses for As, Bi, Cu, Hg, Pd, Pt, S, Sb and Te for samples collected from and adjacent to the J-M Reef. In general, samples from within the reef have higher Pt/Cu, Pd/Cu, Pd/Pt, Te/Bi and S/(Te+Bi) than those collected adjacent to the reef. Vertical compositional profiles through the reef suggest that Pd/Cu and Pt/Cu decrease systematically upsection from mineralized to barren rock. The majority of samples with elevated As, Sb and Hg occur adjacent to the reef, not within it, or in sulfide-poor rocks. Neither magma mixing nor fluid migration models readily explain why the minor quantities of sulfide minerals immediately adjacent to the sulfide-enriched layers that form the J-M Reef have different element ratios than the sulfide minerals that form the reef. If all the sulfides formed by exsolution during a magma mixing event and the modal proportion of sulfide now in the rocks are simply the result of mechanical processes that concentrated the sulfides into some layers and not others, then the composition of the sulfide would not be expected to be different. Models that rely upon ascending liquids or fluids are incompatible with the presence of sulfides that are not enriched in PGE immediately below or interlayered with the PGE-enriched sulfides layers. PGE-enriched postcumulus fluids should have reacted to the same extent with sulfides immediately outside the reef as within the reef. One explanation is that some of the sulfide minerals in the rocks outside the reef have a different origin than those that make up the reef. The

  8. Thermoelectric transport properties of nanostructured FeSb 2 and Ce-based heavy-fermions CeCu and CeAl 3

    Science.gov (United States)

    Pokharel, Mani R.

    Thermoelectric (TE) energy conversion is an all-solid-state technology which can convert waste thermal energy into useful electric power and cool ambience without using harmful gases like CFC. Due to their several advantages over traditional energy conversion technologies, thermoelectric generators (TEG) and coolers (TEC) have drawn enormous research efforts. The objective of this work is to find promising materials for thermoelectric cooling applications and optimize their thermoelectric performances. Finding a material with a good value for the thermoelectric figure-of-merit (ZT) at cryogenic temperatures, specifically below 77 K, has been of great interest. This work demonstrates that FeSb2 1, CeCu6 2 and CeAl3 3, all belonging to a class of materials with strongly correlated electron behavior; exhibit promising thermoelectric properties below 77 K. In general, ZT of a TE material can be increased using two basic approaches: lattice thermal conductivity reduction and power factor (PF) enhancement. The results of this study indicate that nanostructuring effectively decreases the thermal conductivity of FeSb2, CeCu6 and CeAl 3 leading to improved ZT. The approach of introducing point-defect scattering to further reduce the thermal conductivity is successfully implemented for Te-substituted FeSb2 nanostructured samples 4. A semiconductor/metal interface has long been proposed to exhibit enhanced thermoelectric properties. We use this technique by introducing Ag-nanoparticles in the host FeSb2 which further increases ZT by 70% 5. Additionally, a detailed investigation is made on the phonon-drag effect as a possible mechanism responsible for the large value of the Seebeck coefficient of FeSb2 6. We show that the phonon-drag mechanism contributes significantly to the large Seebeck effect in FeSb2 and hence this effect cannot be minor as was proposed in literatures previously. A model based on Kapitza-resistance and effective medium approach (EMA) is used to analyze

  9. Swift heavy ion provoked structural, optical and electrical properties in SnO{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Abhirami, K.M.; Matheswaran, P.; Gokul, B.; Sathyamoorthy, R. [Kongunadu Arts and Science College, PG and Research Department of Physics, Coimbatore, Tamilnadu (India); Asokan, K. [Inter University Accelerator Centre, Materials Science Division, New Delhi (India)

    2013-06-15

    SnO{sub 2} thin films grown on glass substrates at 300 {sup circle} C by reactive thermal evaporation and annealed at 600 {sup circle} C were irradiated by 120 MeV Ag{sup 9+} ions. Though irradiation is known to induce lattice disorder and suppression of crystallinity, we observe grain growth at a certain fluence of irradiation. X-ray diffraction (XRD) revealed the crystalline nature of the films. The particle size estimated by Scherrer's formula for the irradiated films was in the range 10-25 nm. The crystallite size increases with increase in fluence up to 1 x 10{sup 12} ions cm{sup -2}, whereas after that the size starts decreasing. Atomic force microscope (AFM) results showed the surface modification of nanostructures for films irradiated with fluences of 1 x 10{sup 11} ions cm{sup -2} to 1 x 10{sup 13} ions cm{sup -2}. The UV-visible spectrum showed the band gap of the irradiated films in the range of 3.56 eV-3.95 eV. The resistivity decreases with fluence up to 5 x 10{sup 12} ions cm{sup -2} and starts increasing after that. Rutherford Backscattering (RBS) reveals the composition of the films and sputtering of ions due to irradiation at higher fluence. (orig.)

  10. Structural transformations in intermetallic electrodes for lithium batteries : an in situ XRD study of lithiated MnSb and Mn{sub 2}Sb.

    Energy Technology Data Exchange (ETDEWEB)

    Fransson, L. M. L.; Vaughey, J. T.; Edstrom, K.; Thackeray, M. M.; Chemical Engineering; Uppsala Univ.

    2003-01-01

    The electrochemical reactions of lithium with MnSb (NiAs-type structure) and Mn{sub 2}Sb (Cu{sub 2}Sb-type structure) have been investigated by in situ X-ray diffraction. Lithiation of MnSb proceeds via an intermediate LiMnSb structure before transforming, with Mn extrusion, to Li{sub 3}Sb. The reaction is reversible. On delithiation, the X-ray data show solid-solution behavior between Li{sub 3}Sb and LiMnSb, which is facilitated by the strong structural relationship between these two compounds. MnSb electrodes deliver a rechargeable capacity of 330 mAh/g when cycled between 1.5 and 0 V vs. metallic lithium. By contrast, the initial reaction of Mn{sub 2}Sb with lithium proceeds almost directly to Li{sub 3}Sb with little LiMnSb formation. Thereafter, Mn{sub 2}Sb electrodes behave in an almost identical manner to MnSb electrodes, but deliver a rechargeable capacity of less than 300 mAh/g because of the surplus Mn in the electrode. The electrochemical and structural properties of MnSb and Mn{sub 2}Sb are compared with the structurally related compounds Cu{sub 6}Sn{sub 5} (NiAs-type structure) and Cu{sub 2}Sb, respectively.

  11. New sulfido antimonates of the heavy alkali metals. Synthesis, crystal structure and chemical bonding of (K/Rb/Cs){sub 3}SbS{sub 3} and Cs{sub 3}SbS{sub 4} . H{sub 2}O; Neue Sulfido-Antimonate der schweren Alkalimetalle. Synthese, Kristallstruktur und chemische Bindung von (K/Rb/Cs){sub 3}SbS{sub 3} und Cs{sub 3}SbS{sub 4} . H{sub 2}O

    Energy Technology Data Exchange (ETDEWEB)

    Schindler, Lisa V.; Schwarz, Michael; Roehr, Caroline [Freiburg Univ. (Germany). Inst. fuer Anorganische und Analytische Chemie

    2013-12-15

    The new sulfido antimonates(III) (Rb/Cs){sub 3}SbS{sub 3} were prepared from the alkali metal sulfides Rb{sub 2}S/Cs{sub 2}S{sub 2} and elemental antimony and sulfur or Sb{sub 2}S{sub 3} at reaction temperatures of about 700 C. The known isotypic potassium compound was similarly synthesized from the elements. The structures of the light-yellow crystals were refined using single-crystal X-ray data. Both compounds are isotypic to the respective Na salt forming the Na{sub 3}AsS{sub 3} structure type (cubic, space group P2{sub 1}3, K/Rb/Cs: a = 947.21(7)/982.28(5)/1025.92(5) pm, Z = 4, R1 = 0.0159/0.0560/0.0582). The {psi}-tetrahedral SbS{sub 3}{sup 3-} anions with Sb-S bond lengths of 242 pm are arranged in a cubic face centered packing, in which the three crystallographically different A{sup +} cations occupy the tetrahedral and octahedral voids, overall exhibiting a distorted octahedral sulfur coordination. The chemical bonding and the characteristics of the stereochemically active lone electron pair have been investigated by means of FP-LAPW band structure calculations. Needle-shaped crystals of the monohydrate of the antimony(V) salt Cs{sub 3}SbS{sub 4} . H{sub 2}O were obtained from a suspension of Sb{sub 2}O{sub 3}, CsOH and elemental sulfur. Cs{sub 3}SbS{sub 4} . H{sub 2}O crystallizes in a new structure type (monoclinic, space group P2{sub 1}/c, a = 987.17(10), b = 994.83(7), c = 1600.46(14) pm, {beta} = 126.895(8) , Z = 4, R1 = 0.0234). As expected, the Sb-S distances (233.1-234.7 pm) in the nearly ideally tetrahedral anion SbS{sub 4}{sup 3-} are considerably shorter than in the antimonates(III) but match the bond lengths in the anhydrous sulfido antimonate(V) Cs{sub 3}SbS{sub 4}. Due to their similar fcc-like anion packing and the stereochemically active lone electron pair of Sb in the antimonates(III), the whole series of compounds A{sub 3}Sb{sup III,V}S{sub 3/4} shows a uniform structure relation, which is elucidated using crystallographic group

  12. S123b -NQR study of unconventional superconductivity in the filled skutterudite heavy-fermion compound PrOs4Sb12 under high pressure up to 3.82 GPa

    Science.gov (United States)

    Kawasaki, S.; Katayama, K.; Sugawara, H.; Kikuchi, D.; Sato, H.; Zheng, Guo-Qing

    2008-08-01

    We report S123b nuclear-quadrupole-resonance (NQR) measurements of the filled skutterudite heavy-fermion superconductor PrOs4Sb12 under high pressure. The temperature dependence of NQR frequency and the spin-lattice relaxation rate 1/T1 indicate that the crystal-electric-field splitting ΔCEF between the ground-state Γ1 singlet and the first-excited-state Γ4(2) triplet decreases with increasing pressure. ac-susceptibility measurements indicate that the superconducting transition temperature (Tc) also decreases with increasing pressure. However, above Ptilde 2GPa , both ΔCEF and Tc do not depend on external pressure up to P=3.82GPa . These pressure dependences of ΔCEF and Tc suggest an intimate relationship between quadrupole excitations associated with the Γ4(2) level and unconventional superconductivity in PrOs4Sb12 . In the superconducting state, 1/T1 below Tc=1.55 and 1.57 K at P=1.91 and 2.63 GPa shows a power-law temperature variations and is proportional to T5 at temperatures considerably below Tc . These data can be well fitted by the gap model Δ(θ)=Δ0sinθ , with Δ0=3.08kBTc and 3.04kBTc for P=1.91 and 2.63 GPa, respectively. The results indicate that there exist point nodes in the gap function.

  13. Thermodynamic and surface properties of Sb–Sn and In–Sn liquid ...

    Indian Academy of Sciences (India)

    Alloys of Sn are likely to be very promising as an alternative solder in the electronic industry [1–3]. This is because the commonly used solder consists of lead which is known to be ... lation links surface properties of a liquid binary alloy to its bulk thermodynamic ..... For the Sb–Sn alloys, more Sb atoms are present at the. 328.

  14. Experimental study of the excitation functions of deuteron induced reactions on {sup nat}Sn up to 40 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Tarkanyi, F. [Institute of Nuclear Research of the Hungarian Academy of Sciences, H4026 Debrecen (Hungary); Ditroi, F., E-mail: ditroi@atomki.h [Institute of Nuclear Research of the Hungarian Academy of Sciences, H4026 Debrecen (Hungary); Hermanne, A. [Cyclotron Laboratory, Vrije Universiteit Brussel, B1050 Brussels (Belgium); Takacs, S.; Kiraly, B. [Institute of Nuclear Research of the Hungarian Academy of Sciences, H4026 Debrecen (Hungary); Baba, M. [Cyclotron and Radioisotope Center, Tohoku University, Sendai (Japan); Ignatyuk, A.V. [Institute of Physics and Power Engineering, 249020 Obninsk (Russian Federation)

    2011-02-15

    Using the stacked-foil activation technique, cross-sections of deuteron induced reactions on natural Sn were measured up to 40 MeV. Excitation functions are reported for the product nuclides {sup 111}In, {sup 113}Sn, {sup 117m}Sn, {sup 125m}Sn, {sup 125g}Sn, {sup 115}Sb, {sup 116m}Sb, {sup 117}Sb, {sup 118m}Sb {sup 120m}Sb, {sup 122}Sb, {sup 124}Sb and {sup 125}Sb and compared with the earlier published data sets. For all excitation functions comparisons with theoretical calculations using the ALICE-IPPE, EMPIRE, EAF and the TALYS codes were performed.

  15. Cross section measurements of the sup 1 sup 0 sup 2 Pd(p, gamma) sup 1 sup 0 sup 3 Ag, sup 1 sup 1 sup 6 Sn(p, gamma) sup 1 sup 1 sup 7 Sb, and sup 1 sup 1 sup 2 Sn(alpha, gamma) sup 1 sup 1 sup 6 Te reactions relevant to the astrophysical rp- and gamma-processes

    CERN Document Server

    Oezkan, N; Boyd, R N; Cole, A L; Famiano, M; Gueray, R T; Howard, M; Sahin, L; Zach, J J; Haan, R D; Görres, J; Wiescher, M C; Islam, M S; Rauscher, T

    2002-01-01

    Total cross section measurements for the sup 1 sup 0 sup 2 Pd(p, gamma) sup 1 sup 0 sup 3 Ag and sup 1 sup 1 sup 6 Sn(p, gamma) sup 1 sup 1 sup 7 Sb reactions have been performed in the proton energy range 2.6 to 4.25 MeV, and for the sup 1 sup 1 sup 2 Sn(alpha, gamma) sup 1 sup 1 sup 6 Te reaction over the alpha beam energy range 7.0 to 10.5 MeV. An activation technique was used in which gamma rays from decays of the reaction products were detected off-line by two hyper-pure germanium detectors in a low background environment. Where possible, reaction rates are derived and the results compared to those of calculations generated by the NON-SMOKER and the MOST statistical model codes so as to judge their applicability for describing the cross sections needed for network calculations of nucleosynthesis in explosive astrophysical environments via the gamma- and rp-processes.

  16. Radiochemical neutron activation analysis for 36 elements in geological material: Au, Ag, Bi, Br, Cd, Cs, Ge, In, Ir, Ni, Os, Pd, Rb, Re, Sb, Se, Sn, Te, Tl, U, and Zn as well as Sc, Y, and REE

    Energy Technology Data Exchange (ETDEWEB)

    Anders, E; Wolf, R; Morgan, J W; Ebihara, M; Woodrow, A B; Janssens, M J; Hertogen, J

    1988-01-01

    In lunar and terrestrial rocks and in meteorites, the radiochemical neutron activation method decribed here enables determination of the 21 trace and ultratrace elements Ag, Au, Bi, Br, Cd, Cs, Ga, Ge, In, Ir, Ni, Os, Pd, Rb, Re, Sb, Se, Te, Tl, U, Zn, as well as 13 rare earth elements (REE), Sc and Y. Materials, techniques and procedures are discussed. 81 refs.

  17. Experimental study of the excitation functions of proton induced reactions on natSn up to 65 MeV

    Science.gov (United States)

    Hermanne, A.; Tárkányi, F.; Ditrói, F.; Takács, S.; Adam Rebeles, R.; Uddin, M. S.; Hagiwara, M.; Baba, M.; Shubin, Yu.; Kovalev, S. F.

    2006-06-01

    Using the stacked-foil activation technique, cross-sections of proton induced reactions on natural Sn were determined up to 67 MeV. Excitation functions are reported for the first time for the product nuclides 109In, 110In, 111In, 114mIn, 113Sn, 117mSn, 115Sb, 120mSb. Comparison with low energy published data for reactions leading to 116mSb, 117Sb, 118mSb, 122Sb, 124Sb are discussed. For all excitation functions a theoretical calculation using the ALICE-IPPE code was performed. Relevance to the production of medically relevant radioisotopes (111In, 114mIn, 117mSn) is discussed.

  18. Morphological and humidity sensing characteristics of SnO2 –CuO ...

    Indian Academy of Sciences (India)

    Administrator

    ing of the material in mortar with pestle for 6 h, a very fine powder was obtained. Various ratios e.g. 1 : 0⋅25,. 1 : 0⋅5 and 1 :1 were taken for comparative study. 3.3 Preparation of SnO2–SbO2 (S3). The SnO2–SbO2 composite (S3) was prepared from chlo- rides in the laboratory. The SnO2 solution was prepared.

  19. Multivalency of group-V elements in SnO2

    Science.gov (United States)

    Peng, Haowei; Lany, Stephan

    2014-03-01

    Multivalence is an intrinsic property of elements being capable to change their valence state which usually companies with environmental perturbation such as lattice distortion. It commonly shows in transition metal compounds, but also in some some main-group elements, especially heavy group-IV and -V elements. Group-V elements were proposed as n-type dopants in SnO2, and compared with the commercial FTO (F-doped SnO2), the cation-site incorporation can facilitate various growth techniques. However, substituting for Sn4+ ions, the group-V elements can possess either the desired 5 + oxidation state that generates electron charge carriers, or a compensating 3 + oxidation state. Hence, specific attention to this multivalence characteristics is indispensable. To this end, we accurately determine the defect transition energy level ɛ(1 - / 1 +) with respect to the conduction band minimum, by combining the state-of-art quasi-particle GW and hybrid functional calculations. Group-V elements including P, As, Sb and Bi are considered, which have strong site-preference on Sn instead of on O sites. Supported by the US Department of Energy, Office of Energy Efficiency and Renewable Energy.

  20. Changes of Heavy Metals in Pollutant Release and Transfer Registers (PRTRs) in Korea

    Science.gov (United States)

    Kwon, Yong-Su; Bae, Mi-Jung; Park, Young-Seuk

    2014-01-01

    Industrial effluent containing heavy metals discharged into streams may pose high toxicity risks to aquatic organisms and to human health. Therefore, it is important to understand how to change the amount of effluent with heavy metals discharged from industries into open aquatic ecosystems both for effective management of heavy metals and to foster sustainable ecosystems. This study was conducted to characterize the release of heavy metals from industries based on the Pollutant Release and Transfer Registers database in Korea from 1999 to 2010. From the database, we selected nine heavy metals (Pb, Cd, Mn, Sb, Cu, Zn, Cr, Sn, and Ni) and compared the differences in their effluent for different types of industries. The heavy metal effluents released into freshwater ecosystems were classified into four clusters through the learning process of the self-organizing map. Cluster 1 was characterized by the relatively higher effluent volumes of heavy metals, whereas cluster 4 had lower effluent volumes. The different patterns of the effluent volumes in heavy metals were closely associated with the differences of industrial types, and the changes of effluents of heavy metals reflected the changes in regulations and laws for aquatic ecosystem management. PMID:24577281

  1. Quadrupole moment of the 8/sup -/ isomer in /sup 112/Sb

    Energy Technology Data Exchange (ETDEWEB)

    Mahnke, H.; Dafni, E.; Rafailovich, M.H.; Sprouse, G.D.; Vapirev, E.

    1982-08-01

    The quadrupole interaction of the 8/sup -/ isomeric state (T/sub 1/2/ = 536 ns) in /sup 112/Sb has been measured using the time differential perturbed angular distribution method. The linear momentum transfer from the /sup 103/Rh(/sup 12/C, 3n) reaction recoiled the isomeric nuclei into single crystals of Sb and Sn and a polycrystalline In foil. From the quadrupole coupling constant for the 8/sup -/ state of /sup 112/Sb in Sb, the quadrupole moment was obtained relative to the moment of the stable ground state of /sup 121/Sb: Vertical BarQ(/sup 112/Sb,8/sup -/)/Q(/sup 121/Sb,(5/2)/sup +/)Vertical Bar = 1.958(10). The value is in accordance with the description of the isomer as an odd proton coupled to a neutron-excited Sn core. In addition, the measured coupling constants in Sn and In allow the determination of the quadrupole moments of isomers in /sup 120,122/Sb and /sup 115/Sb.

  2. Extension of the excitation functions of deuteron induced reactions on {sup nat}Sn up to 50 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Hermanne, A., E-mail: aherman@vub.ac.be [Cyclotron Laboratory, Vrije Universiteit Brussel, B1050 Brussels (Belgium); Tárkányi, F.; Ditrói, F.; Takács, S. [Institute of Nuclear Research of the Hungarian Academy of Sciences, H4026 Debrecen (Hungary)

    2017-01-15

    Using the stacked-foil activation technique, cross-sections of deuteron induced reactions on natural Sn targets were determined up to 50 MeV. Excitation functions are reported for the product nuclides {sup 116m}Sb, {sup 117}Sb, {sup 118m}Sb, {sup 120m}Sb {sup 122m+g}Sb, {sup 124m+g}Sb, {sup 110}Sn(cum), {sup 113m+g}Sn(cum), {sup 117m}Sn, {sup 110m}In(cum), {sup 110g}In, {sup 111m+g}In(cum), {sup 113m}In, {sup 114m}In {sup 115m}In. Comparison with earlier published data at lower energy is discussed. For all excitation functions a theoretical calculation using the TALYS 1.6 (on-line TENDL-2015 library) code is shown.

  3. Extension of the excitation functions of deuteron induced reactions on natSn up to 50 MeV

    Science.gov (United States)

    Hermanne, A.; Tárkányi, F.; Ditrói, F.; Takács, S.

    2017-01-01

    Using the stacked-foil activation technique, cross-sections of deuteron induced reactions on natural Sn targets were determined up to 50 MeV. Excitation functions are reported for the product nuclides 116mSb, 117Sb, 118mSb, 120mSb 122m+gSb, 124m+gSb, 110Sn(cum), 113m+gSn(cum), 117mSn, 110mIn(cum), 110gIn, 111m+gIn(cum), 113mIn, 114mIn 115mIn. Comparison with earlier published data at lower energy is discussed. For all excitation functions a theoretical calculation using the TALYS 1.6 (on-line TENDL-2015 library) code is shown.

  4. High current density Esaki tunnel diodes based on GaSb-InAsSb heterostructure nanowires.

    Science.gov (United States)

    Ganjipour, Bahram; Dey, Anil W; Borg, B Mattias; Ek, Martin; Pistol, Mats-Erik; Dick, Kimberly A; Wernersson, Lars-Erik; Thelander, Claes

    2011-10-12

    We present electrical characterization of broken gap GaSb-InAsSb nanowire heterojunctions. Esaki diode characteristics with maximum reverse current of 1750 kA/cm(2) at 0.50 V, maximum peak current of 67 kA/cm(2) at 0.11 V, and peak-to-valley ratio (PVR) of 2.1 are obtained at room temperature. The reverse current density is comparable to that of state-of-the-art tunnel diodes based on heavily doped p-n junctions. However, the GaSb-InAsSb diodes investigated in this work do not rely on heavy doping, which permits studies of transport mechanisms in simple transistor structures processed with high-κ gate dielectrics and top-gates. Such processing results in devices with improved PVR (3.5) and stability of the electrical properties.

  5. Monitoring of heavy metal concentrations in home outdoor air using moss bags

    Energy Technology Data Exchange (ETDEWEB)

    Rivera, Marcela, E-mail: arivera@creal.ca [Centre for Research in Environmental Epidemiology CREAL, Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Barcelona (Spain); Universitat Pompeu Fabra, Barcelona (Spain); CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Zechmeister, Harald [University of Vienna, Faculty of Life Sciences, Vienna (Austria); Medina-Ramon, Mercedes; Basagana, Xavier [Centre for Research in Environmental Epidemiology CREAL, Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Barcelona (Spain); CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Foraster, Maria [Centre for Research in Environmental Epidemiology CREAL, Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Barcelona (Spain); Universitat Pompeu Fabra, Barcelona (Spain); CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Bouso, Laura [Centre for Research in Environmental Epidemiology CREAL, Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Barcelona (Spain); CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain); Moreno, Teresa [Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Barcelona (Spain); Solanas, Pascual; Ramos, Rafael [Research Unit, Family Medicine, Girona, Jordi Gol Institute for Primary Care Research (IDIAP Jordi Gol), Catalan Institute of Health, Catalunya (Spain); Department of Medical Sciences, School of Medicine, University of Girona (Spain); Koellensperger, Gunda [University of Natural Resources and Applied Life Sciences, Vienna (Austria); Deltell, Alexandre [Polytechnic School, GREFEMA, University of Girona (Spain); Vizcaya, David [Centre for Research in Environmental Epidemiology CREAL, Barcelona (Spain); Municipal Institute of Medical Research (IMIM-Hospital del Mar), Barcelona (Spain); Universitat Pompeu Fabra, Barcelona (Spain); CIBER Epidemiologia y Salud Publica (CIBERESP) (Spain)

    2011-04-15

    One monitoring station is insufficient to characterize the high spatial variation of traffic-related heavy metals within cities. We tested moss bags (Hylocomium splendens), deployed in a dense network, for the monitoring of metals in outdoor air and characterized metals' long-term spatial distribution and its determinants in Girona, Spain. Mosses were exposed outside 23 homes for two months; NO{sub 2} was monitored for comparison. Metals were not highly correlated with NO{sub 2} and showed higher spatial variation than NO{sub 2}. Regression models explained 61-85% of Cu, Cr, Mo, Pb, Sb, Sn, and Zn and 72% of NO{sub 2} variability. Metals were strongly associated with the number of bus lines in the nearest street. Heavy metals are an alternative traffic-marker to NO{sub 2} given their toxicological relevance, stronger association with local traffic and higher spatial variability. Monitoring heavy metals with mosses is appealing, particularly for long-term exposure assessment, as mosses can remain on site many months without maintenance. - Research highlights: > Moss bags can be used to measure the metal's long-term spatial distribution within cities. > Heavy metals in mosses are not highly correlated with ambient NO{sub 2} concentrations. > Heavy metals show higher spatial variation and association with traffic than NO{sub 2}. > Bus lines in the nearest street explain 75-85% of Mo, Cr, Sb, Sn and Cu variability. > Moss bags are useful for long-term at home exposure assessment in epidemiological studies. - The long-term spatial distribution of heavy metals, measured with moss bags, is mainly determined by proximity to bus lines.

  6. Hard and soft X-ray spectroscopy of Sm-based heavy-fermion compounds SmFe{sub 4} P{sub 12} and SmOs{sub 4} Sb{sub 12}

    Energy Technology Data Exchange (ETDEWEB)

    Yamasaki, A. [Department of Physics, Faculty of Science and Engineering, Konan University, Kobe 658-8501 (Japan)], E-mail: yamasaki@konan-u.ac.jp; Imada, S.; Higashimichi, H.; Fujiwara, H.; Saita, T.; Miyamachi, T.; Sekiyama, A. [Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531 (Japan); Sugawara, H. [Graduate School of Human and Natural Environment Science, University of Tokushima, Tokushima 770-8502 (Japan); Kikuchi, D.; Sato, H. [Graduate School of Science, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397 (Japan); Higashiya, A. [RIKEN, Mikazuki, Sayo, Hyogo 679-5148 (Japan); Yabashi, M. [Japan Synchrotron Research Institute, Mikazuki, Sayo, Hyogo 679-5198 (Japan); Tamasaku, K.; Miwa, D.; Ishikawa, T. [RIKEN, Mikazuki, Sayo, Hyogo 679-5148 (Japan); Suga, S. [Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531 (Japan)

    2007-05-15

    We have carried out soft and hard X-ray spectroscopy of Sm-based filled skutterudites SmFe{sub 4} P{sub 12} and SmOs{sub 4} Sb{sub 12}. Sm 3d-4f resonant photoemission and Sm 3d-4f X-ray absorption spectra suggest that SmOs{sub 4} Sb{sub 12} has much more strongly mixed Sm valence state than SmFe{sub 4} P{sub 12} in the bulk. On the other hand, the Sm trivalent state is dominant on the surface of SmOs{sub 4} Sb{sub 12}.

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

    Science.gov (United States)

    Sungkhaphaitoon, Phairote; Plookphol, Thawatchai

    2018-02-01

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

  8. Antiferromagnetism in semiconducting SrMn2Sb2 and BaMn2Sb2 single crystals

    Science.gov (United States)

    Sangeetha, N. S.; Smetana, V.; Mudring, A.-V.; Johnston, D. C.

    2018-01-01

    Crystals of SrMn2Sb2 and BaMn2Sb2 were grown using Sn flux and characterized by powder and single-crystal x-ray diffraction, respectively, and by single-crystal electrical resistivity ρ , heat capacity Cp, and magnetic susceptibility χ measurements versus temperature T , and magnetization versus field M (H ) isotherm measurements. SrMn2Sb2 adopts the trigonal CaAl2Si2 -type structure, whereas BaMn2Sb2 crystallizes in the tetragonal ThCr2Si2 -type structure. The ρ (T ) data indicate semiconducting behaviors for both compounds with activation energies of ≳0.35 eV for SrMn2Sb2 and 0.16 eV for BaMn2Sb2 . The χ (T ) and Cp(T ) data reveal antiferromagnetic (AFM) ordering at TN = 110 K for SrMn2Sb2 and 450 K for BaMn2Sb2 . The anisotropic χ (T ≤TN) data also show that the ordered moments in SrMn2Sb2 are aligned in the hexagonal a b plane, whereas the ordered moments in BaMn2Sb2 are aligned collinearly along the tetragonal c axis. The a b -plane M (H ) data for SrMn2Sb2 exhibit a continuous metamagnetic transition at low fields 0 literature for Mn pnictides with the CaAl2Si2 and ThCr2Si2 crystal structures show that the TN values for the CaAl2Si2 -type compounds are much smaller than those for the ThCr2Si2 -type materials.

  9. Shell model calculation for Te and Sn isotopes in the vicinity of {sup 100}Sn

    Energy Technology Data Exchange (ETDEWEB)

    Yakhelef, A.; Bouldjedri, A. [Physics Department, Farhat abbas University, Setif (Algeria); Physics Department, Hadj Lakhdar University, Batna (Algeria)

    2012-06-27

    New Shell Model calculations for even-even isotopes {sup 104-108}Sn and {sup 106,108}Te, in the vicinity of {sup 100}Sn have been performed. The calculations have been carried out using the windows version of NuShell-MSU. The two body matrix elements TBMEs of the effective interaction between valence nucleons are obtained from the renormalized two body effective interaction based on G-matrix derived from the CD-bonn nucleon-nucleon potential. The single particle energies of the proton and neutron valence spaces orbitals are defined from the available spectra of lightest odd isotopes of Sb and Sn respectively.

  10. Study the chemical composition and biological outcomes resulting from the interaction of the hormone adrenaline with heavy elements: Infrared, Raman, electronic, 1H NMR, XRD and SEM studies

    Science.gov (United States)

    Ibrahim, Omar B.; Mohamed, Mahmoud A.; Refat, Moamen S.

    2014-01-01

    Heavy metal adrenaline complexes formed from the reaction of adrenaline with Al3+, Zn2+, Sn2+, Sb3+, Pb2+and Bi3+ ions in methanolic solvent at 60 °C. The final reaction products have been isolated and characterization using elemental analyses (% of carbon, hydrogen and nitrogen), conductivity measurements, mid infrared, Raman laser, UV-Vis, 1H NMR spectra, X-ray powder diffraction, scanning electron microscopy and energy-dispersive X-ray spectroscopy (EDX). Upon the spectroscopic, conductivity and elemental analyses, the stoichiometric reactions indicated that the data obtained refer to 1:2 (M:L) for Zn2+, Sn2+, Pb2+and Bi3+ complexes [Zn(Adr)2(Cl)2], [Sn(Adr)2]Cl2, [Pb(Adr)2](NO3)2 and [Bi(Adr)2(Cl)2]Cl, while the molar ratio 1:3 (M:L) for Al3+ and Sb3+ with formulas [Al(Adr)3](NO3)3 and [Sb(Adr)3]Cl3. The infrared and Raman laser spectra interpreted the mode of interactions which associated through the two phenolic groups of catechol moiety. The adrenaline chelates have been screened for their in vitro antibacterial activity against four bacteria, Gram-positive (Bacillus subtilis and Staphylococcus aureus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) and two strains of fungus (Aspergillus flavus and Candida albicans). The metal chelates were shown to possess more antibacterial and antifungal activities than the free adrenaline chelate.

  11. Morphological and humidity sensing characteristics of SnO2–CuO ...

    Indian Academy of Sciences (India)

    This paper reports the synthesis of SnO2–CuO, SnO2–Fe2O3 and SnO2–SbO2 composites of nano oxides and comparative study of humidity sensing on their electrical resistances. CuO, Fe2O3 and SbO2 were added within base material SnO2 in the ratio 1 : 0.25, 1 : 0.50 and 1 : 1. Characterizations of materials were done ...

  12. Un nouvel oxyde naturel de Au et Sb

    Science.gov (United States)

    Johan, Zdenek; Šrein, Vladimir

    1998-04-01

    A gold-antimony X-ray amorphous oxide, resulting from a hydrothermal alteration of aurostibite, AuSb 2, occurs in the Krásná Hora gold deposit, Czech Republic. Its reflectivity is close to that of goethite. The average composition obtained by electron microprobe analyses (wt. %) is: Au - 68.32; Cu - 0.10; Sb - 21.26; As - 0.30; Si - 0.21; O - 8.44; total 98.63. This yields the empirical formula (Au 0.677Cu 0.003Sb 0.341As 0.008) 1.029O. The[(Au + Cu)/(Sb + As)] at ratio varies from 1.86 to 1.95. Among possible formulae satisfying the equilibrium of charges, that implying unique valence states for Au and/or Sb was retained. It can be written Au 1+2Sb 3+O 2(OH) with the theoretical composition (wt, %): Au - 69.76; Sb - 21.54; O - 8.50; H - 0.20. This Au- and Sb-bearing oxide is associated with native gold, electrum, aurostibite, arsenopyrite and pyrite in a quartz gangue. The powder pattern of AuSbO 3 was indexedon an orthorhombic unit-cell with a = 5.00(2); b = 12.46(4); c = 5.43(2) Å, Z = 4, Q calc = 7.20 g.cm 3, assuming a replacement of Sb 3+ by Au 3+ in the valentinite-type crystal structure.

  13. Coexistence of magnetic order and valence fluctuations in a heavy fermion system Ce{sub 2}Rh{sub 3}Sn{sub 5}

    Energy Technology Data Exchange (ETDEWEB)

    Gamza, Monika [Jeremiah Horrocks Institute, University of Central Lancashire, Preston (United Kingdom); MPI CPfS, Dresden (Germany); Institute of Physics, University of Silesia, Katowice (Poland); Gumeniuk, Roman [Institute of Experimental Physics, Freiberg University of Mining and Technology, Freiberg (Germany); MPI CPfS, Dresden (Germany); Schnelle, Walter; Burkhardt, Ulrich; Rosner, Helge [MPI CPfS, Dresden (Germany); Slebarski, Andrzej [Institute of Physics, University of Silesia, Katowice (Poland)

    2016-07-01

    While most Ce-based intermetallics contain either trivalent or intermediate-valent Ce ions, only for a few compounds a coexistence of both species has been reported. Here, we present a combined experimental and theoretical study based on thermodynamic measurements and spectroscopic data together with ab-initio electronic structure calculations aiming at exploring magnetic properties of Ce ions in two nonequivalent sites in Ce{sub 2}Rh{sub 3}Sn{sub 5}. Ce L{sub III} XAS spectra give direct evidence for valence fluctuations. Magnetization measurements show an onset of an antiferromagnetic order at T{sub N}∼2.5 K. The electronic structure calculations suggest that the magnetic ordering is related only to one Ce sublattice. This is in-line with a small entropy associated with the magnetic transition S{sub mag}∼0.35 R ln2 per Ce atom as revealed by the specific heat measurement. Furthermore, the temperature dependence of the magnetic susceptibility can be well described assuming that there are fluctuating moments of Ce{sup 3+} ions in one sublattice, whereas Ce atoms from the second sublattice are in a nonmagnetic intermediate valence state.

  14. Multiple superconducting phases in heavy fermion compounds ...

    Indian Academy of Sciences (India)

    Here we show that multiple superconducting phases are present in heavy fermion superconductors, CeCoIn5 [2] and PrOs4Sb12 [3] , both of which were discovered very recently. The superconducting gap function of PrOs4Sb12 was investigated using thermal transport measurements in magnetic field rotated relative to the.

  15. SN Refsdal

    DEFF Research Database (Denmark)

    Kelly, P. L.; Brammer, G.; Selsing, J.

    2016-01-01

    (SNe), and we find strong evidence for a broad H-alpha P-Cygni profile in the HST grism spectrum at the redshift (z = 1.49) of the spiral host galaxy. SNe IIn, powered by circumstellar interaction, could provide a good match to the light curve of SN Refsdal, but the spectrum of a SN IIn would not show...... 1987A, we estimate it would have an ejecta mass of 20+-5 solar masses. The evolution of the light curve at late times will provide additional evidence about the potential existence of any substantial circumstellar material (CSM). Using MOSFIRE and X-shooter spectra, we estimate a subsolar host-galaxy...

  16. Determination of the excitation energy and angular momentum of the quasi-projectiles produced in the heavy ion collisions Xe + Sn; Determination de l'energie d'excitation et du moment angulaire des quasi-projectiles produits dans les collisions d'ions lourds Xe + Sn

    Energy Technology Data Exchange (ETDEWEB)

    Genouin-Duhamel, Emmanuel [Lab. de Physique Corpusculaire, Caen Univ., 14 Caen (France)

    1999-04-08

    This work is a contribution to the study of properties of hot nuclei formed in heavy ion collisions at intermediate energies. The experiment has been performed with the INDRA multidetector. It is shown that most of the reaction cross section is associated with binary dissipative collisions, accompanied by the production of particles from a region between the two reaction partners. This study is focussed on excitation energy and angular momentum of projectile-like fragment (PLF) in {sup 129}Xe + {sup nat}Sn reactions from 25 to 50 MeV per nucleon. Several methods are used to characterize hot nuclei (velocity, charge, mass and excitation energy). All these methods are compared between them and indicate that high energies are deposited in the nuclei during collision (it may exceed the nucleus binding energy). The angular momentum transferred into intrinsic spin to PLF in the peripheral collisions has been deduced from angular distributions and kinetic energies of the emitted light charged particles (atomic number smaller ar equal to 2). Both methods agree qualitatively. The spin values decrease with the violence of the collision. These values correspond to values averaged over the whole deexcitation chain of nuclei. The predictions of transport models reproduce qualitatively the most peripheral collisions and suggest that high spins are transferred to PLF (from 30 to 50 {Dirac_h}). Larger angular momentum values are observed at the lowest incident energy. The time hierarchy in the evaporation process and the role of mid-rapidity emission are also discussed.

  17. Portuguese granites associated with Sn-W and Au mineralizations

    Directory of Open Access Journals (Sweden)

    Ana M.R. Neiva

    2002-01-01

    Full Text Available In northern and central Portugal, there are different tin-bearing granites. Most of them are of S-type, others have mixed characteristics of I-type and S-type granites and a few are of I-type. Tin-tungsten deposits are commonly associated with Hercynian tin-bearing S-type granites. Some quartz veins with wolframite are associated with an I-type granite, which has a low Sn content. In suites of tin-bearing S-type granitic rocks, Sn content increases as a function of the degree of fractional crystallization. Greisenizations of two-mica S-type granites associated with tin-tungsten mineralizations are accompanied by an increase in SiO2, H2O+, Sn, W, Nb, Ta, Rb, Zn, and Pb and decrease in MgO, Na2O, V, Sc,Zr, and Sr. The granite associated with the Jales gold deposit is of S-type and strongly differentiated like the tin-bearing S-type granites, but it has a very low Sn content. During fractional crystallization, Si, Rb, Sn, Pb, Au, As, Sb, and S increase. During increasing degree of hydrothermal alteration of this granite at the gold-quartz vein walls, there are progressive increases in K2O, H2O+, Sn, Cs, Cu, Pb, Au, Sb, As, and S.

  18. Alternative anode materials for lithium-ion batteries: a study of Ag 3Sb

    Science.gov (United States)

    Vaughey, J. T.; Fransson, L.; Swinger, H. A.; Edström, K.; Thackeray, M. M.

    Silver antimonide, Ag 3Sb, in which silver and antimony are both electrochemically active toward lithium, has been studied as an anode for lithium-ion batteries. The rate of capacity fade on cycling was monitored as a function of the voltage window, which has provided further information about the causes of capacity fade in intermetallic electrode systems. From the voltage profiles, and by comparison with the behavior of SnSb, InSb and Cu 2Sb electrodes, the electrochemical reaction of Li/Ag 3Sb cells was determined to take place in several discrete stages: first, by a displacement reaction in which lithium replaces Ag in the Ag 3Sb structure in a two-step process between 0.9 and 0.7 V to form Li 3Sb via Li 2AgSb; and second, by reaction of lithium with the extruded silver between 0.2 and 0.0 V to form Li xAg compounds (1≤ x≤4). The rate of capacity fade that occurs when cells are cycled between 1.2 and 0.0 V was significantly reduced by limiting the reaction to either: (1) the low voltage region (0.7-0.0 V), which provided a stable capacity of ˜300 mAh/g; or (2) to a wider operating window (1.2-0.1 V, 250 mAh/g), in which the formation of Li xAg phases was suppressed.

  19. 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.

  20. Determination of heavy metals in apricot (Prunus armeniaca and almond (Prunus amygdalus oils

    Directory of Open Access Journals (Sweden)

    Issa Mohammadpourfard

    2015-03-01

    Full Text Available Background and purpose: Determination of heavy metals in oils is necessary to establish quality standards on a country level. This study aimed to determine of heavy metal contents (Cr, Ni, As, Cd, Hg, Pb, Sb, Sn, Sr, Al in 12 seed oil samples in Iran by inductively coupled plasma-optical emission spectrometry (ICP-OES. Materials and Methods: The concentrations of heavy metal were determined by wet acid digestion methods with nitric acid (65% and 4 ml peroxide hydrogenate on same samples using ICP-OES. Results: Results showed that the average of most important toxic metals detected in apricot oil samples was as follows 721.72 μg/kg for Al 15 μg/kg for Cd, 18 μg/kg for Pb, 14 μg/kg for As and <1 μg/kg for Hg. Furthermore, The average of heavy metals detected in almond oil samples were as follows 1019.73 μg/kg for Al, 10 μg/kg for Cd, 21 μg/kg for Pb and 11 μg/kg for As and <1 μg/kg for Hg. Also in the studied samples, Al was the highest concentrations among all metals. Conclusion: Most of the samples of oils were found to be contaminated with notable amounts of toxic metals which could be a threat to oil quality and human health.

  1. Heavy metals in human teeth dentine: A bio-indicator of metals exposure and environmental pollution.

    Science.gov (United States)

    Asaduzzaman, Khandoker; Khandaker, Mayeen Uddin; Binti Baharudin, Nurul Atiqah; Amin, Yusoff Bin Mohd; Farook, Mohideen Salihu; Bradley, D A; Mahmoud, Okba

    2017-06-01

    With rapid urbanization and large-scale industrial activities, modern human populations are being increasingly subjected to chronic environmental heavy metal exposures. Elemental uptake in tooth dentine is a bioindicator, the uptake occurring during the formation and mineralization processes, stored to large extent over periods of many years. The uptake includes essential elements, most typically geogenic dietary sources, as well as non-essential elements arising through environmental insults. In this study, with the help of the Dental Faculty of the University of Malaya, a total of 50 separate human teeth were collected from dental patients of various ethnicity, age, gender, occupation, dietary habit, residency, etc. Analysis was conducted using inductively coupled plasma-mass spectrometry (ICP-MS), most samples indicating the presence of the following trace elements, placed in order of concentration, from least to greatest: As, Mn, Ba, Cu, Cr, Pb, Zn, Hg, Sb, Al, Sr, Sn. The concentrations have been observed to increase with age. Among the ethnic groups, the teeth of ethnic Chinese showed marginally greater metal concentrations than those of the Indians and Malays, the teeth dentine of females generally showing greater concentrations than that of males. Greater concentrations of Hg, Cu and Sn were found in molars while Pb, Sr, Sb and Zn were present in greater concentrations in incisors. With the elevated concentration levels of heavy metals in tooth dentine reflecting pollution from industrial emissions and urbanization, it is evident that human tooth dentine can provide chronological information on exposure, representing a reliable bio-indicator of environmental pollution. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. New stannite-like p-type thermoelectric material Cu{sub 3}SbSe{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Yang Chongyin; Xu Ke [Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou, Jiangsu 215123 (China); Huang Fuqiang [CAS Key Laboratory of Materials for Energy Conversion, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050 (China); Wu Liming, E-mail: huangfq@mail.sic.ac.cn [Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002 (China)

    2011-07-27

    The ternary chalcogenide of Cu{sub 3}SbSe{sub 4} is demonstrated to be a novel p-type thermoelectric material, by doping Sn in the Sb site. The figure of merit (ZT) in Cu{sub 3}Sb{sub 0.975}Sn{sub 0.025}Se{sub 4} reaches 0.75 at 673 K. Such excellent thermoelectric properties are attributed to the crystal structure of Cu{sub 3}SbSe{sub 4}, consisting of the three-dimensional Cu/Se framework ({sup 3}{sub {infinity}}[Cu{sub 3}Se{sub 4}]) acting as the hole conduction pathway and the [SbSe{sub 4}] tetrahedra. The Cu/Se framework is suitable to tune the electrical conductivity by doping. The insertion of tetrahedral [SbSe{sub 4}] causes a more distorted diamond-like structure, providing a relatively lower lattice thermal conductivity and a relatively large Seebeck coefficient. The origin of the structure-electrical property relationship and ZT enhancement by Sn doping is elucidated.

  3. The Relativistic Effects on the Carbon-Carbon Coupling Constants Mediated by a Heavy Atom.

    Science.gov (United States)

    Wodyński, Artur; Malkina, Olga L; Pecul, Magdalena

    2016-07-21

    The (2)JCC, (3)JCC, and (4)JCC spin-spin coupling constants in the systems with a heavy atom (Cd, In, Sn, Sb, Te, Hg, Tl, Pb, Bi, and Po) in the coupling path have been calculated by means of density functional theory. The main goal was to estimate the relativistic effects on spin-spin coupling constants and to explore the factors which may influence them, including the nature of the heavy atom and carbon hybridization. The methods applied range, in order of reduced complexity, from the Dirac-Kohn-Sham (DKS) method (density functional theory with four-component Dirac-Coulomb Hamiltonian), through DFT with two- and one-component zeroth-order regular approximation (ZORA) Hamiltonians, to scalar effective core potentials (ECPs) with the nonrelativistic Hamiltonian. The use of DKS and ZORA methods leads to very similar results, and small-core ECPs of the MDF and MWB variety reproduce correctly the scalar relativistic effects. Scalar relativistic effects usually are larger than the spin-orbit coupling effects. The latter tend to influence the most the coupling constants of the sp(3)-hybridized carbon atoms and in compounds of the p-block heavy atoms. Large spin-orbit coupling contributions for the Po compounds are probably connected with the inverse of the lowest triplet excitation energy.

  4. Realization of single and double axial InSb-GaSb heterostructure nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Ghalamestani, Sepideh Gorji [Solid State Physics, Lund University, Lund (Sweden); Ek, Martin [Center for Analysis and Synthesis, Lund University, Lund (Sweden); Dick, Kimberly A. [Solid State Physics, Lund University, Lund (Sweden); Center for Analysis and Synthesis, Lund University, Lund (Sweden)

    2014-03-15

    Heteroepitaxial growth of III-Sb nanowires allows for the formation of various interesting complex structures and enables the combination of their remarkable properties. In this Letter, we investigate the heteroepitaxial growth of Au-seeded InSb and GaSb nanowires using metalorganic vapor phase epitaxy. We demonstrate successful single and double axial InSb-GaSb heterostructures in both directions. The formation properties of the grown nanowires including the compositional change of the particle and the interface sharpness are further discussed. In addition, the decomposition of InSb and GaSb segments and their side facet evolution are explained. XEDS compositional line scans overlaid on STEM HAADF image along the InSb-GaSb-InSb nanowire indicating sharp interface from GaSb to InSb segment and graded interface in the opposite direction. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  5. A model for the composition modifications in the Cu-Sb-O system

    Energy Technology Data Exchange (ETDEWEB)

    Stan, M.

    1997-05-01

    THE SN-SB-CU-O SYSTEM HAS BEEN EXTENSIVELY STUDIED BUT SYSTEMATIC PHASE EQUILIBRIUM STUDIES HAVE NOT BEEN APPROACHED. THE SYSTEM CONTAINS USEFUL CERAMICS WITH SPECIFIC ELECTRICAL AND MAGNETIC PROPERTIES, EMPLOYED AS SENSORS, ELECTRODES AND CATALYSTS. AS A PRELIMINARY STEP TO THE PHASE DIAGRAM CALCULATION, THE PAPER AIMS TO PRESENT A MODEL FOR THE COMPOSITION MODIFICATIONS IN THE CU-SB-O SYSTEM, WHICH IS THE MOST COMPLEX OF ALL SUBSYSTEMS. EXOTHERMIC EFFECTS ALONG WITH MASS INCREASES CAN BE OBSERVED IN DTA/GA CURVES, WERE ASSIGNED, FOR ALL SAMPLES, TO SB2O3 AND SB2O4 OXIDATION AND TO CUSB2O6 FORMATION: (1) APPROX. EQUAL 500 DIG C SB2O3 + 1/2 O2 DOUBLE RIGHT ARROW SB2O4; (2) {gt} 750 DIG C SB2O4 + CUO + 1/2 O2 DOUBLE RIGHT ARROW CUSB2O6. FOR THE SAMPLES HAVING CUO IN EXCESS, THE REDUCTION OF CUO TO CUO AND THE FORMATION OF THE CU4SBO4.5 COMPOUND SIMULTANEOUSLY OCCUR: {gt} 950 dig C CUSB2O6 + 7CuO double right arrow (1-r) CUSB2O6+7(1-r)cow+ 2rCu4SbO4.5 + 2rO2 where rEpsilon (0, 1) is the fraction of CUSB2O6 that transforms into Cu4SbO4.5. All the experimental evidences show that the Equations (1), (2) and (3) are good descriptions of the transformations that occurs in the CuO-Sb2O3 system along with the temperature. If the reactions are considered as completed, including a=1 in IQ. (3), then the quantity of oxygen that is gained or lost can be calculated for each sample. It is important to note that Equations (2) and (3) should be carefully solved because of the excess quantities of cow or SB2O4 that can be found in some samples. The calculated values of mass variation are in a good agreement with those obtained from the experimental GT diagrams. The atomic fractions of Cu, Sb and Awe content change in the system and they can be also calculated. The model assumes that at room temperature the compositions lay on the CuO-Sb2O3 line as shown in Fig. 1.

  6. Phase transitions in lithiated Cu{sub 2}Sb anodes for lithium batteries : an in-situ x-ray diffraction study.

    Energy Technology Data Exchange (ETDEWEB)

    Fransson, L. M. L.; Vaughey, J. T.; Benedek, R.; Edstrom, K.; Thomas, J. O.; Thackeray, M. M.; Chemical Engineering; Uppsala Univ.

    2001-07-01

    Copper antimonide, Cu{sub 2}Sb, has been investigated as a negative electrode (anode) for rechargeable lithium batteries by in situ X-ray diffraction of Li/Cu{sub 2}Sb cells. The data show that lithium isinserted into Cu{sub 2}Sb with a concomitant extrusion of copper, which initiates a phase transition to a lithiated zinc-blende-type structure, Li{sub x}Cu{sub 2-y}Sb for 0 < x {<=} 2 and 0 {<=} y {<=} 1, yielding Li{sub 2}CuSb at x = 2, y = 1. Further lithiation results in the displacement of the remaining copper to yield Li{sub 2+z}Cu{sub 1-z}Sb compositions (0 < z {<=} 1) with the end member Li{sub 3}Sb. The Sb array remains intact in a face-centred arrangement throughout these reactions, despite a 42% expansion of the array. The reactions are reversible; they occur between 1.0 and 0 V vs. Li{sup 0}, and deliver a steady capacity of approximately 290 mAh/g after one conditioning cycle. The lithium insertion/metal extrusion reactions with the Cu{sub 2}Sb structure bear a resemblance to those observed previously with Cu{sub 6}Sn{sub 5} and InSb.

  7. Microstructural features induced by spray forming of a ternary Pb–Sn ...

    Indian Academy of Sciences (India)

    Unknown

    tance of the alloy. However, due to the slow cooling rate involved in the casting process, agglomeration of SnSb compound occurs in the casting due to its higher .... seaths to avoid their contact with the metal substrate. The spray nozzle and substrate were leveled to align the thermocouples with the axis of the melt spray.

  8. Properties and Microstructures of Sn-Bi-X Lead-Free Solders

    Directory of Open Access Journals (Sweden)

    Fan Yang

    2016-01-01

    Full Text Available The Sn-Bi base lead-free solders are proposed as one of the most popular alloys due to the low melting temperature (eutectic point: 139°C and low cost. However, they are not widely used because of the lower wettability, fatigue resistance, and elongation compared to traditional Sn-Pb solders. So the alloying is considered as an effective way to improve the properties of Sn-Bi solders with the addition of elements (Al, Cu, Zn, Ga, Ag, In, Sb, and rare earth and nanoparticles. In this paper, the development of Sn-Bi lead-free solders bearing elements and nanoparticles was reviewed. The variation of wettability, melting characteristic, electromigration, mechanical properties, microstructures, intermetallic compounds reaction, and creep behaviors was analyzed systematically, which can provide a reference for investigation of Sn-Bi base solders.

  9. Bonding in ZnSb

    DEFF Research Database (Denmark)

    Bjerg, Lasse; Madsen, Georg K. H.; Iversen, Bo Brummerstedt

    Thermoelectric materials are capable of converting waste heat into usable electric energy. The conversion efficiency depends critically on the electronic band structure. Theoretical calculations predict the semiconducting ZnSb to have a promising efficiency if it is n-doped. The details of the lo......Thermoelectric materials are capable of converting waste heat into usable electric energy. The conversion efficiency depends critically on the electronic band structure. Theoretical calculations predict the semiconducting ZnSb to have a promising efficiency if it is n-doped. The details...

  10. Enhanced thermoelectric properties of n-type NbCoSn half-Heusler by improving phase purity

    Directory of Open Access Journals (Sweden)

    Ran He

    2016-10-01

    Full Text Available Here we report the thermoelectric properties of NbCoSn-based n-type half-Heuslers (HHs that were obtained through arc melting, ball milling, and hot pressing process. With 10% Sb substitution at the Sn site, we obtained enhanced n-type properties with a maximum power factor reaching ∼35 μW cm−1 K−2 and figure of merit (ZT value ∼0.6 in NbCoSn0.9Sb0.1. The ZT is doubled compared to the previous report. In addition, the specific power cost ($ W−1 is decreased by ∼68% comparing to HfNiSn-based n-type HH because of the elimination of Hf.

  11. Structural and magnetic properties of GaSb:MnSb granular layers

    Energy Technology Data Exchange (ETDEWEB)

    Dynowska, E., E-mail: dynow@ifpan.edu.pl [Institute of Physics Polish Academy of Sciences, al. Lotnikow 32/46, PL-02668 Warsaw (Poland); Bak-Misiuk, J.; Romanowski, P.; Domagala, J.Z. [Institute of Physics Polish Academy of Sciences, al. Lotnikow 32/46, PL-02668 Warsaw (Poland); Sadowski, J. [Institute of Physics Polish Academy of Sciences, al. Lotnikow 32/46, PL-02668 Warsaw (Poland); MAX-Lab, Lund University P.O. Box. 118, S-22100 Lund (Sweden); Wojciechowski, T.; Kret, S.; Kurowska, B. [Institute of Physics Polish Academy of Sciences, al. Lotnikow 32/46, PL-02668 Warsaw (Poland); Kwiatkowski, A. [Institute of Experimental Physics, Faculty of Physics, University of Warsaw, ul. Hoza 69, PL-00681 Warsaw (Poland); Caliebe, W. [Hasylab at DESY, Notkestr. 85, D-22607 Hamburg (Germany)

    2011-10-15

    The results of structural and magnetic characterization of GaMnSb layers grown on GaSb(0 0 1) and GaAs(1 1 1) substrates are presented. The presence of hexagonal, highly oriented MnSb inclusions embedded in GaSb matrix has been demonstrated. The lattice parameters of these inclusions were the same as those for bulk MnSb for the layers grown on GaSb(1 0 0) substrate while for the layers grown on GaAs(1 1 1) the MnSb inclusions were strained. The influence of a presence of MnSb clusters on the lattice parameter of GaSb matrix has been demonstrated. It was confirmed that in all cases the MnSb clusters exhibit a ferromagnetic behavior at room temperature.

  12. Optical Sensitizing of Photorefractive Sn2P2S6 With CW and Pulsed Pre-Exposure (Preprint)

    Science.gov (United States)

    2015-06-16

    nonlinear scattering, and recovery to the initial transmission, respectively. 1 Distribution A. Approved for public release (PA): distribution... antimony doping. The second conclusion is in line with our published data on the identification of secondary centers in Sn2P2S6:Sb using the EPR...optical sensitizing of photorefraction in antimony doped Sn2P2S6 crystals. AKNOWLEDGMENTS The financial support of the European Office of

  13. The influence of Sb doping on the structural, optical and electrical properties of tin oxide thin film

    Science.gov (United States)

    Yusnidar, M. N.; Fauzia, V.; Handoko, D.; Hanum, L.

    2017-04-01

    Antimony-doped Tin Oxide (Sb:SnO2), shortened as ATO, has become more popular due to their great technological importance. ATO was considered as important transparent conducting material for optoelectronic devices and sensors application because of its unique and special characteristic such as high transparency in visible region, and high electrons concentration and mobility. In this study, the Sb:SnO2 thin film have been fabricated with low cost and simple ultrasonic spray pyrolysis method. SnO2 thin film was deposited with three different Sb concentrations namely 1, 2, and 3 wt%. The structural, morphological, optical and electrical properties of this film have been analyzed by using X-ray diffraction, scanning electron microscopy, UV-VIS and four point probe instruments. Based on the optical and electrical properties characterization, the best concentration of Sb doping was 2wt% because its transmittance was above 80% at all wavelength range measured, and the electrical resistivity was quite low, at 0.663 × 10-3 Ω cm.

  14. High-pressure high-temperature crystal growth of equiatomic rare earth stannides RENiSn and REPdSn

    Energy Technology Data Exchange (ETDEWEB)

    Heymann, Gunter [Institut für Allgemeine, Anorganische und Theoretische Chemie, Leopold-Franzens-Universität Innsbruck, Innrain 80-82, A-6020 Innsbruck (Austria); Heying, Birgit; Rodewald, Ute Ch.; Janka, Oliver [Institut für Anorganische und Analytische Chemie, Universität Münster, Corrensstraße 30, 48149 Münster (Germany); Huppertz, Hubert, E-mail: Hubert.Huppertz@uibk.ac.at [Institut für Allgemeine, Anorganische und Theoretische Chemie, Leopold-Franzens-Universität Innsbruck, Innrain 80-82, A-6020 Innsbruck (Austria); Pöttgen, Rainer, E-mail: pottgen@uni-muenster.de [Institut für Anorganische und Analytische Chemie, Universität Münster, Corrensstraße 30, 48149 Münster (Germany)

    2016-04-15

    The two series of equiatomic rare earth (RE) stannides RENiSn and REPdSn were systematically studied with respect to high-pressure modifications. The normal-pressure (NP) low-temperature (LT) modifications were synthesized by arc-melting and subsequently treated under high-pressure (P{sub max}=11.5 GPa) and high-temperature (T{sub max}=1570 K) conditions in a Walker-type multi-anvil press. The pressure and temperature conditions were systematically varied in order to improve the crystallization conditions. The new ZrNiAl-type high-pressure modifications HP-RENiSn (RE=Sc, Y, La, Gd–Lu) and HP-REPdSn (RE=Y, Sm–Dy) were obtained in 80 mg quantities, several of them in X-ray pure form. Some of the REPdSn stannides with the heavy rare earth elements show high-temperature (HT) modifications. The structures of HP-ScNiSn, HP-GdNiSn, HP-DyNiSn (both ZrNiAl-type), NP-YbNiSn, and HT-ErPdSn (both TiNiSi-type) were refined from single crystal diffractometer data, indicating full ordering of the transition metal and tin sites. TiNiSi-type NP-EuPdSn transforms to MgZn{sub 2}-type HP-EuPdSn: P6{sub 3}/mmc, a=588.5(2), c=917.0(3) pm, wR2=0.0769, 211 F{sup 2} values, 11 variables. The structure refinement indicated statistical occupancy of the palladium and tin sites on the tetrahedral network. The X-ray pure high-pressure phases were studied with respect to their magnetic properties. HP-YPdSn is a Pauli paramagnet. The susceptibility data of HP-TbNiSn, HP-DyNiSn, HP-GdPdSn, and HP-TbPdSn show experimental magnetic moments close to the free ion values of RE{sup 3+} and antiferromagnetic ordering at low temperature with the highest Néel temperature of 15.8 K for HP-TbPdSn. HP-SmPdSn shows the typical Van Vleck type behavior along with antiferromagnetic ordering at T{sub N}=5.1 K. HP-EuPdSn shows divalent europium and antiferromagnetic ordering at 8.9 K followed by a spin reorientation at 5.7 K. - Graphical abstract: Packing of the polyhedra in the high-pressure phase of EuPdSn

  15. Incorporation of Sb and As in MBE grown GaAsxSb1-x layers

    Science.gov (United States)

    Zederbauer, Tobias; Andrews, Aaron Maxwell; MacFarland, Don; Detz, Hermann; Schrenk, Werner; Strasser, Gottfried

    2017-03-01

    With the increasing interest in low effective mass materials for intersubband devices, mixed As-Sb compounds, like GaAsxSb1-x or AlxIn1-xAsySb1-y, gain more and more attention. The growth of these materials, however, still provides significant challenges due to the complex interaction between As and Sb. In this work, we provide an in-depth study on the incorporation of Sb into the GaAsxSb1-x layers and compare our findings to the present literature on this topic. It is found that both the composition and the crystal quality of GaAsxSb1-x layers are strongly influenced by the growth rate due to the As-for-Sb exchange reaction which takes place at the growing surface, and that high crystal quality can be achieved when the growth is performed under Sb limited conditions.

  16. MOVPE deposition of Sb2Te3 and other phases of Sb-Te system on sapphire substrate

    Science.gov (United States)

    Kuznetsov, P. I.; Shchamkhalova, B. S.; Yapaskurt, V. O.; Shcherbakov, V. D.; Luzanov, V. A.; Yakushcheva, G. G.; Jitov, V. A.; Sizov, V. E.

    2017-08-01

    The films of Sb-Te system have been deposited by MOVPE on (0 0 0 1) Al2O3 substrates with thin ZnTe buffer layers at different temperatures and Te/Sb ratios in the vapor phase. X-ray diffractometry, SEM microscopy, Raman and EDX spectroscopy were used to study as-grown films. The surface morphology and stoichiometry of Sb-Te films strongly depend on Te/Sb ratio in vapor phase. We have deposited the phases of homologous series nSb2·mSb2Te3 with following stoichiometries: Sb2Te3, Sb4Te5, Sb8Te9, Sb10Te9, Sb4Te3, Sb2Te, Sb8Te3, Sb10Te3, Sb16Te3, Sb18Te3 and Sb. Transport properties of Sb2Te3, Sb4Te5, Sb8Te9, Sb4Te3, Sb2Te were evaluated using Van der Pauw technique at 300 K.

  17. Evidence for Unconventional Strong-Coupling Superconductivity in PrOs4Sb12: An Sb Nuclear Quadrupole Resonance Study

    Science.gov (United States)

    Kotegawa, H.; Yogi, M.; Imamura, Y.; Kawasaki, Y.; Zheng, G.-Q.; Kitaoka, Y.; Ohsaki, S.; Sugawara, H.; Aoki, Y.; Sato, H.

    2003-01-01

    We report Sb-NQR results which evidence a heavy-fermion (HF) behavior and an unconventional superconducting (SC) property in Pr(Os4Sb12 with Tc=1.85 K. The temperature (T) dependence of nuclear-spin-lattice-relaxation rate, 1/T1, and NQR frequency unravel a low-lying crystal-electric-field splitting below T0˜10 K, associated with Pr3+(4f2)-derived ground state. In the SC state, 1/T1 shows neither a coherence peak just below Tc K nor a T3-like power-law behavior observed for anisotropic HF superconductors with the line-node gap. The isotropic energy gap with its size Δ/kB=4.8 K seems to open up across Tc below T*˜2.3 K. It is surprising that Pr(Os4Sb12 looks like an isotropic HF superconductor—it may indeed argue for Cooper pairing via quadrupolar fluctuations.

  18. The fire ant social chromosome supergene variant Sb shows low diversity but high divergence from SB.

    Science.gov (United States)

    Pracana, Rodrigo; Priyam, Anurag; Levantis, Ilya; Nichols, Richard A; Wurm, Yannick

    2017-06-01

    Variation in social behaviour is common, yet little is known about the genetic architectures underpinning its evolution. A rare exception is in the fire ant Solenopsis invicta: Alternative variants of a supergene region determine whether a colony will have exactly one or up to dozens of queens. The two variants of this region are carried by a pair of 'social chromosomes', SB and Sb, which resemble a pair of sex chromosomes. Recombination is suppressed between the two chromosomes in the supergene region. While the X-like SB can recombine with itself in SB/SB queens, recombination is effectively absent in the Y-like Sb because Sb/Sb queens die before reproducing. Here, we analyse whole-genome sequences of eight haploid SB males and eight haploid Sb males. We find extensive SB-Sb differentiation throughout the >19-Mb-long supergene region. We find no evidence of 'evolutionary strata' with different levels of divergence comparable to those reported in several sex chromosomes. A high proportion of substitutions between the SB and Sb haplotypes are nonsynonymous, suggesting inefficacy of purifying selection in Sb sequences, similar to that for Y-linked sequences in XY systems. Finally, we show that the Sb haplotype of the supergene region has 635-fold less nucleotide diversity than the rest of the genome. We discuss how this reduction could be due to a recent selective sweep affecting Sb specifically or associated with a population bottleneck during the invasion of North America by the sampled population. © 2017 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

  19. The atomistic mechanism for Sb segregation and As displacement of Sb in InSb(001) surfaces

    Science.gov (United States)

    Anderson, Evan M.; Millunchick, Joanna M.

    2018-01-01

    Interfacial broadening occurs in mixed-anion alloy heterostructures such as InAs/InAsSb due to both Sb-segregation and As-for-Sb exchange. In order to determine the atomistic mechanisms for these processes, we conduct ab initio calculations coupled with a cluster expansion formalism to determine the surface reconstructions of the pure and As-exposed InSb(001) surfaces. This approach provides a predicted phase diagram for pure InSb that is in better agreement with experiments. Namely, the α2(2 × 4) and α3c(4 × 4) structures are ultimately stable at 0K, but the α(4 × 3) and α2c(2 × 6) are within 1 meV/Å2. Exposure of the InSb(001) surface to As results in the As atoms infiltrating into the crystal and displacing subsurface Sb, thus providing the atomistic mechanisms for experimental observations of the As-for-Sb exchange reaction and Sb segregation. Experiments show that the widely reported A-(1 × 3) reconstruction is actually comprised of multiple reconstructions, which is consistent with the prediction of several nearly stable possible reconstructions.

  20. One Step Synthesis of Uniform SnO2 Electrode by UV Curing Technology toward Enhanced Lithium-Ion Storage.

    Science.gov (United States)

    Wei, Hang; Xia, Zhonghong; Xia, Dingguo

    2017-03-01

    A uniform anode material composed of ultrasmall tin oxide (SnO2) nanoparticles with an excellent lithium-ion (Li-ion) storage performance is obtained for the first time through one step UV curing technology. The diameter of ∼3 nm-sized SnO2 particles is uniformly dispersed in the styrylpyridinium (SbQ) polymer because of its photo-cross-linking property. The in situ cross-linking of SbQ polymer not only assist synthesis of uniform ultrasmall SnO2, but act as a strong adhesion binder on SnO2 nanoparticles, thereby effectively accommodating the volume expansion of SnO2 anodes during cycling process. The uniform electrode exhibits substantially higher specific capacity and longer cycling stability compared with the SnO2 nanoparticles electrodes treated by traditional PVDF-mixing method. A stable specific capacity of 572.5 mA h g(-1) of the SnO2 electrode derived from UV curing technology is obtained at a current density of 0.2 C (156.2 mA g(-1)) after 150 cycles. Even at high rate of 5 C (3905 mA g(-1)), the electrode still demonstrates specific capacity of 440.2 mA h g(-1). Therefore, the scalable and low-cost synthetic approach described herein can readily be extended to other nanomaterials electrodes to improve their lithium-storage properties.

  1. Transport properties of a-SnxSb20Se80-x (8 <= x <= 18) chalcogenide glass

    Science.gov (United States)

    Kumar, P.; Bindra, K. S.; Suri, N.; Thangaraj, R.

    2006-02-01

    X-ray diffraction and differential scanning calorimetric studies were performed on bulk Sn-Sb-Se chalcogenide alloys, which were obtained by the conventional melt quenching technique. The addition of Sn reduces the crystalline nature of Sb20Se80 chalcogenide alloy and amorphous samples are obtained for a-SnxSb20Se80-x 8 Philip-Thorpe rigidity transition occurs. Thin films were obtained by the thermal evaporation method for dc conductivity and optical measurements. From the temperature dependence of dc conductivity measurements, the activation energy (ΔE) and the pre-exponential factor (σ0) were calculated for each glassy alloy. An approximate linear dependence of ln σ0 on ΔE is observed which proved the validity of the Meyer-Neldel rule in the investigated samples. It has been observed that the difference in dc activation energy (ΔE) is less than half of the optical band gap (E0) indicating that the Fermi level is not located near the centre of the gap.

  2. Heavy Chain Diseases

    Science.gov (United States)

    ... heavy chain produced: Alpha Gamma Mu Alpha Heavy Chain Disease Alpha heavy chain disease (IgA heavy chain ... disease or lead to a remission. Gamma Heavy Chain Disease Gamma heavy chain disease (IgG heavy chain ...

  3. Properties and Microstructures of Sn-Ag-Cu-X Lead-Free Solder Joints in Electronic Packaging

    Directory of Open Access Journals (Sweden)

    Lei Sun

    2015-01-01

    Full Text Available SnAgCu solder alloys were considered as one of the most popular lead-free solders because of its good reliability and mechanical properties. However, there are also many problems that need to be solved for the SnAgCu solders, such as high melting point and poor wettability. In order to overcome these shortcomings, and further enhance the properties of SnAgCu solders, many researchers choose to add a series of alloying elements (In, Ti, Fe, Zn, Bi, Ni, Sb, Ga, Al, and rare earth and nanoparticles to the SnAgCu solders. In this paper, the work of SnAgCu lead-free solders containing alloying elements and nanoparticles was reviewed, and the effects of alloying elements and nanoparticles on the melting temperature, wettability, mechanical properties, hardness properties, microstructures, intermetallic compounds, and whiskers were discussed.

  4. Electrical properties of GaSb/InAsSb core/shell nanowires.

    Science.gov (United States)

    Ganjipour, Bahram; Sepehri, Sobhan; Dey, Anil W; Tizno, Ofogh; Borg, B Mattias; Dick, Kimberly A; Samuelson, Lars; Wernersson, Lars-Erik; Thelander, Claes

    2014-10-24

    Temperature dependent electronic properties of GaSb/InAsSb core/shell and GaSb nanowires have been studied. Results from two-probe and four-probe measurements are compared to distinguish between extrinsic (contact-related) and intrinsic (nanowire) properties. It is found that a thin (2-3 nm) InAsSb shell allows low barrier charge carrier injection to the GaSb core, and that the presence of the shell also improves intrinsic nanowire mobility and conductance in comparison to bare GaSb nanowires. Maximum intrinsic field effect mobilities of 200 and 42 cm(2) Vs(-1) were extracted for the GaSb/InAsSb core/shell and bare-GaSb NWs at room temperature, respectively. The temperature-dependence of the mobility suggests that ionized impurity scattering is the dominant scattering mechanism in bare GaSb while phonon scattering dominates in core/shell nanowires. Top-gated field effect transistors were fabricated based on radial GaSb/InAsSb heterostructure nanowires with shell thicknesses in the range 5-7 nm. The fabricated devices exhibited ambipolar conduction, where the output current was studied as a function of AC gate voltage and frequency. Frequency doubling was experimentally demonstrated up to 20 kHz. The maximum operating frequency was limited by parasitic capacitance associated with the measurement chip geometry.

  5. Negative heat capacities in central Xe+Sn reactions

    Energy Technology Data Exchange (ETDEWEB)

    Le Neindre, N.; Bougault, R.; Gulminelli, F. [Laboratoire de Physique Corpusculaire, IN2P3-CNRS, ISMRA et Universite, 14 - Caen (France)] [and others

    2000-02-01

    In this study the fluctuation method is applied to the 32-50 A.MeV Xe + Sn central collisions detected with the INDRA multidetector. This method based on kinetic energy fluctuations allows the authors to provide information on the liquid gas phase transition in nuclear multifragmentation. In the case of Xe + Sn central reactions a divergence in the total heat capacity is observed. This divergence corresponds to large fluctuations on the detected fragment partitions. A negative heat capacity branch is measured and so tends to confirm the observation of a first order phase transition in heavy-ion collisions. (A.C.)

  6. Synthesis, photocatalytic and antimicrobial properties of SnO2, SnS2 and SnO2/SnS2 nanostructure.

    Science.gov (United States)

    Fakhri, Ali; Behrouz, Sajjad; Pourmand, Melika

    2015-08-01

    Nanoscale SnO2, SnS2 and SnO2/SnS2 were synthesized by hydrothermal treatment method and characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET), Barrett-Joyner-Halenda (BJH) and UV-vis spectra. The photocatalytic activity of SnO2, SnS2 and SnO2/SnS2 were tested with Enrofloxacin antibiotic. The tetragonal and hexagonal SnO2 and SnS2 phase was confirmed through XRD, respectively. The photocatalytic results indicated that the SnO2/SnS2 enhanced the photocatalytic activity and could be effectively used as photocatalyst for degradation of Enrofloxacin antibiotic pollutant. The results of antibacterial experiment under visible light irradiation demonstrate that the SnO2/SnS2 nanocomposite exhibit enhanced antibacterial efficiency compared with pure SnO2 and SnS2. The antifungal activity of the nanoscale SnO2, SnS2 and SnO2/SnS2 against Candida albicans was assessed using the disc-diffusion susceptibility tests. It was seen that the antifungal activity of SnO2/SnS2 nanocomposite is higher than the pure SnO2 and SnS2 toward pathogenic C. albicans. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. The Sandbridge SB3011 Platform

    Directory of Open Access Journals (Sweden)

    Daniel Iancu

    2007-03-01

    Full Text Available This paper describes the Sandbridge Sandblaster real-time software-defined radio platform. Specifically, we describe the SB3011 system-on-a-chip multiprocessor. We describe the software development system that enables real-time execution of communications and multimedia applications. We provide results for a number of interesting communications and multimedia systems including UMTS, DVB-H, WiMAX, WiFi, and NTSC video decoding. Each processor core achieves 600 MHz at 0.9 V operation while typically dissipating 75 mW in 90 nm technology. The entire chip typically dissipates less than 500 mW at 0.9 V.

  8. Low-energy spin fluctuations in filled skutterudites YbFe{sub 4}Sb{sub 12} and LaFe{sub 4}Sb{sub 12} investigated through {sup 121}Sb nuclear quadrupole and {sup 139}La nuclear magnetic resonance measurements

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, A; Iemura, S; Wada, S [Department of Physics, Graduate School of Science, Kobe University, Kobe 657-8501 (Japan); Ishida, K [Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502 (Japan); Shirotani, I; Sekine, C [Faculty of Engineering, Muroran Institute of Technology, Mizumoto, Muroran 050-8585 (Japan)

    2008-05-14

    We have elucidated low-energy spin fluctuations in the new filled skutterudites YbFe{sub 4}Sb{sub 12} and LaFe{sub 4}Sb{sub 12} synthesized at high pressures, through {sup 121}Sb nuclear quadrupole resonance (NQR) and {sup 139}La nuclear magnetic resonance (NMR) measurements. The longitudinal spin-lattice relaxation rate 1/T{sub 1} of {sup 121}Sb in YbFe{sub 4}Sb{sub 12} provides evidence that upon cooling below {approx}20 K, the compound transforms from the localized 4f electron state of Yb{sup 3+} ions to a nonmagnetic heavy Fermi liquid state, originating from the mixing of 4f electrons with conduction electrons. Whereas, the Curie-Weiss type behaviour of the {sup 139}La Knight shift and {sup 121}Sb- 1/T{sub 1} in LaFe{sub 4}Sb{sub 12} indicate that the compound remains in the localized electron state down to 1.4 K, it in fact originates from 3d electrons of Fe in [Fe{sub 4}Sb{sub 12} ] anions. In both compounds, the transversal nuclear spin-spin relaxation rate 1/T{sub 2} exhibits a clear peak at T*{approx_equal}32 and {approx_equal}23K respectively. The origin of the 1/T{sub 2} peak is discussed in terms of the freezing of the thermal vibration of Sb cages or rare-earth ions filled in each Sb cage. By comparing the experimental results of the present study with those previously reported for the compounds synthesized at ambient pressure, it is pointed out that both the strongly correlated electron properties and the thermal vibrations are greatly modified with the increase of rare-earth atom deficiency.

  9. Computational Study of Nb-Doped-SnO2/Pt Interfaces: Dopant Segregation, Electronic Transport, and Catalytic Properties

    DEFF Research Database (Denmark)

    Fu, Qiang; Halck, Niels Bendtsen; Hansen, Heine Anton

    2017-01-01

    Carbon black, a state-of-the-art cathode material for proton exchange membrane fuel cells (PEMFCs), suffers from severe corrosion in practical applications. Niobium-doped tin dioxide (NTO) is a promising alternative to support the Pt catalysts at the cathodes. Here, through a combined density...... in the subsurface layers of the NTO substrate, whereas their transport across the Pt/NTO interface is hindered by a high thermodynamic barrier under the operating condition of PEMFCs. The interfacial transport of Sn is, however, more facile, indicating possible formations of Sn Pt alloys and tin oxides...... adsorbate toward the oxygen reduction reaction. We also investigate the co-doped SnO2 substrates by both Nb and Sb elements, and find that a small amount of Nb dopants could further improve the electronic transport of the Pt/Sb-doped-SnO2 interface. The fundamental understanding generated here will help...

  10. Electromigration Critical Product to Measure Effect of Underfill Material in Suppressing Bi Segregation in Sn-58Bi Solder

    Science.gov (United States)

    Zhao, Xu; Takaya, Satoshi; Muraoka, Mikio

    2017-08-01

    Recently, we detected length-dependent electromigration (EM) behavior in Sn-58Bi (SB) solder and revealed the existence of Bi back-flow, which retards EM-induced Bi segregation and is dependent on solder length. The cause of the back-flow is attributed to an oxide layer formed on the SB solder. At present, underfill (UF) material is commonly used in flip-chip packaging as filler between chip and substrate to surround solder bumps. In this study, we quantitatively investigated the effect of UF material as a passivation layer on EM in SB solder strips. EM tests on SB solder strips with length of 50 μm, 100 μm, and 150 μm were conducted simultaneously. Some samples were coated with commercial thermosetting epoxy UF material, which acted as a passivation layer on the Cu-SB-Cu interconnections. The value of the critical product for SB solder was estimated to be 38 A/cm to 43 A/cm at 353 K to 373 K without UF coating and 59 A/cm at 373 K with UF coating. The UF material acting as a passivation layer suppressed EM-induced Bi segregation and increased the threshold current density by 37% to 55%. However, at very high current density, this effect became very slight. In addition, Bi atoms can diffuse to the anode side through the Sn phase, hence addition of microelements to the Sn phase to form obstacles, such as intermetallic compounds, may retard Bi segregation in SB solder.

  11. Cross sections of deuteron-induced reactions on {sup nat}Sb up to 50 MeV

    Energy Technology Data Exchange (ETDEWEB)

    Takacs, S., E-mail: stakacs@atomki.hu [Institute of Nuclear Research, Hungarian Academy of Science, 4026 Debrecen (Hungary); Takacs, M.P. [Institute of Physics, University of Debrecen, 4026 Debrecen (Hungary); Hermanne, A. [Cyclotron Laboratory, Vrije Universiteit Brussel, Brussel 1090 (Belgium); Tarkanyi, F. [Institute of Nuclear Research, Hungarian Academy of Science, 4026 Debrecen (Hungary); Adam Rebeles, R. [Cyclotron Laboratory, Vrije Universiteit Brussel, Brussel 1090 (Belgium)

    2012-05-01

    Highlights: Black-Right-Pointing-Pointer Cross sections of deuteron induced reactions on natural antimony. Black-Right-Pointing-Pointer Production of Te, Sb and Sn isotopes. Black-Right-Pointing-Pointer Comparison of experimental cross sections with results of TALYS calculations. Black-Right-Pointing-Pointer Thick target yields. Black-Right-Pointing-Pointer Production of {sup 117m}Sn for medical use. - Abstract: In the frame of a systematic study of the activation cross sections of deuteron-induced nuclear reactions, excitation functions for formation of {sup 118,119m,119g,121m,121g,123m}Te, {sup 118m,120m,122g,124g}Sb and {sup 117m}Sn on {sup nat}Sb targets were determined up to 50 MeV. Cross sections were measured with the activation method using a stacked foil irradiation technique. Excitation functions of the investigated reactions were compared with data reported in literature and results of theoretical calculations made by the TALYS code. From the measured cross section data integral thick target yields were calculated and compared with experimental integral yield data reported in the literature.

  12. Tunnel switch diode based on AlSb/GaSb heterojunctions

    OpenAIRE

    Cheng, X.-C.; Cartoixà, X.; Barton, M. A.; Hill, C. J.; McGill, T. C.

    2000-01-01

    We report on tunnel switch diodes based on AlSb barriers and GaSb p–n junctions grown by molecular beam epitaxy. These were the devices with thyristor like switching in the GaSb/AlSb system. The characteristic "S" shaped current–voltage curve was found to occur for structures with AlSb barriers less than 300 Å thick. The switching voltage and current density exhibited less sensitivity to barrier and epilayer thickness than was predicted by the punch-through model. The results were correlated ...

  13. Isomer and beta decay spectroscopy in the 132Sn region with EURICA

    Directory of Open Access Journals (Sweden)

    Jungclaus A.

    2014-03-01

    Full Text Available The first EURICA campaign with high intensity Uranium beams took place at RIKEN in November/December 2012. Within this campaign experiment NP1112-RIBF85 was performed dedicated to the study of the isomeric and beta decays of neutronrich Cd, In, Sn and Sb isotopes towards and beyond the N=82 neutron shell closure. In this contribution we present a first status report of the analysis of the extensive data set obtained in this experiment.

  14. Isomer and beta decay spectroscopy in the 132Sn region with EURICA

    Science.gov (United States)

    Jungclaus, A.; Simpson, G. S.; Gey, G.; Taprogge, J.; Nishimura, S.; Doornenbal, P.; Lorusso, G.; Söderström, P.-A.; Sumikama, T.; Xu, Z.; Baba, H.; Browne, F.; Fukuda, N.; Inabe, N.; Isobe, T.; Jung, H. S.; Kameda, D.; Kim, G. D.; Kim, Y.-K.; Kojouharov, I.; Kubo, T.; Kurz, N.; Kwon, Y. K.; Li, Z.; Sakurai, H.; Schaffner, H.; Suzuki, H.; Takeda, H.; Vajta, Z.; Watanabe, H.; Wu, J.; Yagi, A.; Yoshinaga, K.; Bönig, S.; Daugas, J.-M.; Drouet, F.; Gernhäuser, R.; Ilieva, S.; Kröll, T.; Montaner-Pizá, A.; Moschner, K.; Mücher, D.; Nishibata, H.; Orlandi, R.; Steiger, K.; Wendt, A.

    2014-03-01

    The first EURICA campaign with high intensity Uranium beams took place at RIKEN in November/December 2012. Within this campaign experiment NP1112-RIBF85 was performed dedicated to the study of the isomeric and beta decays of neutronrich Cd, In, Sn and Sb isotopes towards and beyond the N=82 neutron shell closure. In this contribution we present a first status report of the analysis of the extensive data set obtained in this experiment.

  15. Nonlinear I–V characteristics study of doped SnO2

    Indian Academy of Sciences (India)

    Unknown

    Abstract. When tin oxide is doped with Sb2O3 and CoO, it shows highly nonlinear current (I)–voltage (V) characteristics. Addition of CoO leads to creation of oxygen vacancies and helps in sintering of SnO2. Anti- mony oxide acts as a donor and increases the conductivity. The results are nearly the same when antimony.

  16. Ultra Fast Timing Measurements at $^{78}$Ni and $^{132}$Sn

    CERN Multimedia

    2002-01-01

    We propose to measure level lifetimes in the exotic nuclei of $^{81}$Ga and $^{80}$Ga in the vicinity of $^{78}$Ni and of $^{135}$Sb and $^{134}$Sb above $^{132}$Sn by the time-delayed technique. These are relatively simple nuclear systems with a few particles and/or holes outside of the doubly-magic core thus can be treated rather precisely within the shell model. The anticipated new structure information on these nuclei, and in particular the lifetime results will put constraints on the model parameters and will serve to verify their predictions. The selected nuclei are some of the most exotic ones just above $^{78}$Ni or $^{132}$Sn, where the transition rates can be studied at present. Of the strongest interest is the nucleus of $^{81}$Ga, which has only 3 valence protons outside of $^{78}$Ni with the lowest proton orbits being $p_{3/2}$ and $f_{5/2}$. The Ml transition between these states, although allowed by the selection rules, should be $\\textit{l}$-forbidden thus very slow. This should give rise to a...

  17. Cloning and transcript analysis of type 2 metallothionein gene (SbMT-2) from extreme halophyte Salicornia brachiata and its heterologous expression in E. coli.

    Science.gov (United States)

    Chaturvedi, Amit Kumar; Mishra, Avinash; Tiwari, Vivekanand; Jha, Bhavanath

    2012-05-15

    Salicornia brachiata is an extreme halophyte growing luxuriantly in the coastal marshes and frequently exposed to various abiotic stresses including heavy metals. A full length type 2 metallothionein (SbMT-2) gene was isolated using RACE and its copy number was confirmed by southern blot analysis. Transcript expression of SbMT-2 gene was analyzed by semi-quantitative Rt-PCR and real time quantitative (qRT) PCR. Expression of SbMT-2 gene was up-regulated concurrently with zinc, copper, salt, heat and drought stress, down regulated by cold stress while unaffected under cadmium stress. Heterologous expression of SbMT-2 gene enhances metal accumulation and tolerance in E. coli. Metal-binding characteristics of SbMT-2 protein show its possible role in homeostasis and/or detoxification of heavy metals. Significant tolerance was observed by E. coli cells expressing recombinant SbMT-2 for Zn(++), Cu(++) and Cd(++) compared to cells expressing GST only. Sequestration of zinc was 4-fold higher compared to copper and in contrast SbMT-2 inhibits the relative accumulation of cadmium by 1.23-fold compared to GST protein. Fusion protein SbMT-2 showed utmost affinity to zinc (approx. 2.5 fold to Cu(++) and Cd(++)) followed by copper and cadmium ions with same affinity. Halophyte S. brachiata has inherent resilience of varying abiotic tolerance therefore SbMT-2 gene could be a potential candidate to be used for enhanced metal tolerance and heavy metal phytoremediation. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Electrical properties of highly conducting Sno2:Sb nanocrystals synthesized using a nonaqueous sol gel method

    OpenAIRE

    Conti, Tiago Góes; Chiquito, A. J.; Silva, Rafael Oliveira da; Longo, Elson [UNESP; Leite, Edson Roberto

    2010-01-01

    This work describes the synthesis of highly conducting antimony-doped tin oxide (ATO) nanocrystals prepared via a nonaqueous sol–gel route in the size range of 4–6 nm and provides insights into its electrical properties. The antimony composition was varied from 1 to 18 mol% and the lowest resistivity (4.0 × 10−4Ω·cm) was observed at room temperature in the SnO2:8.8 mol% Sb composition. The samples were evaluated by X-ray diffraction, high-resolution transmission electron microscopy, energy-di...

  19. Suzaku Results of SN 1006: Chemical Abundances of the ``youngest'' Galactic Type Ia Supernova Remnant

    Science.gov (United States)

    Koyama, Katsuji

    2008-05-01

    SN 1006 is one of the supernova remnants (SNR) recorded in the Japanese diary ``Meigetsuki''. From the historical records including Meigetsuki, we conclude that SN 1006 was the brightest type Ia supernova remnant. We report on the observations of SN 1006 with the X-ray Imaging Spectrometers (XIS) on board the 5-th Japanese X-ray satellite Suzaku. We found that the ionization age of SN 1006 is the youngest among any Galactic SNRs, hence is the best SNR to study early phase of type Ia. In the X-ray spectrum, we found the K-shell emission lines from heavy elements, in particular that from iron, for the first time. The X-ray emitting plasma is highly overabundant in heavy elements, hence are likely due to ejecta. The abundance pattern agrees well to the theoretical prediction of type Ia supernova.

  20. Evidence for a spin pseudogap in the normal state of superconducting Mo{sub 3}Sb{sub 7}

    Energy Technology Data Exchange (ETDEWEB)

    Tran, V H; Miiller, W [Institute of Low Temperature and Structure Research, Polish Academy of Sciences, PO Box 1410, 50-950 Wroclaw (Poland); Hillier, A D; Adroja, D T [ISIS Facility, Rutherford Appleton Laboratory, Chilton, Oxfordshire OX11 0QX (United Kingdom); Bukowski, Z [Laboratory for Solid State Physics, ETH Zuerich, 8093 Zuerich (Switzerland)

    2009-12-02

    Using muon spin relaxation (muSR) and inelastic neutron scattering (INS) we have investigated the normal state of the superconductor Mo{sub 3}Sb{sub 7} and the reference compound Ru{sub 3}Sn{sub 7}. The muSR experiments on Ru{sub 3}Sn{sub 7} reveal static and relatively slow dynamic relaxations, which are ascribed to a random static nuclear dipole field and thermally activated muon motion, respectively. INS experiments on Ru{sub 3}Sn{sub 7}, on the other hand, reveal three phononic excitations at 11, 18 and 23 meV, substantiating the assertion of Einstein and Debye oscillations derived from the specific heat and electrical resistivity data. The distinct difference in the muSR as well as INS spectra between Ru{sub 3}Sn{sub 7} and Mo{sub 3}Sb{sub 7} provides strong evidence for a magnetic/electronic nature of the phase transition at T{sup *} = 50 K in the Mo-based compound. On the basis of the muSR and INS data, the energy spin pseudogap of 150(10) K was estimated. The observed weak magnetism in the dynamic susceptibility chi{sup ''}(Q,omega) and residual longitudinal field relaxation at 5 K imply a static ordering or quantum fluctuations.

  1. State-of-the-art Sn2+-based ternary oxides as photocatalysts for water splitting: electronic structures and optoelectronic properties

    KAUST Repository

    Noureldine, Dalal

    2016-09-19

    Developing visible light responsive metal oxide photocatalysts is a challenge that must be conquered to achieve high efficiency for water splitting or hydrogen evolution reactions. Valence band engineering is possible by forming ternary oxides using the combination of a metal cation with an s2d10 electronic configuration and a transition metal oxide with a d0 configuration. Many (Sn2+, Bi3+, Pb2+)-based ternary metal oxide photocatalysts have been reported for hydrogen and/or oxygen evolution under visible irradiation. Sn2+-based materials have attracted particular attention because tin is inexpensive, abundant and more environmentally friendly than lead or bismuth. In this review, we provide a fruitful library for Sn2+-based photocatalysts that have been reported to evolve hydrogen using sacrificial reagents, including SnNb2O6, Sn2Nb2O7, SnTaxNb2−xO6, SnTa2O6, Sn2Ta2O7, SnWO4 (α and β phases), SnSb2O6·nH2O, and Sn2TiO4. The synthesis method used in the literature and the resultant morphology and crystal structure of each compound are discussed. The density functional theory (DFT) calculations of the electronic structure and density of states are provided, and the consequent optoelectronic properties such as band gap, nature of the bandgap, dielectric constant, and effective masses are summarized. This review will help highlight the main challenges for Sn2+-based materials.

  2. The microstructure and properties of as-cast Sn-Zn-Bi solder alloys

    Directory of Open Access Journals (Sweden)

    Mladenović Srba A.

    2012-01-01

    Full Text Available Research on the lead-free solders has attracted wide attention, mostly as the result of the implementation of the Directive on the Restriction of the Use of Hazardous Substances in Electrical and Electronic Equipment. The Sn-Zn solder alloys have been considered to be one of the most attractive lead-free solders due to its ability to easily replace Sn-Pb eutectic alloy without increasing the soldering temperature. Furthermore, the mechanical properties are comparable or even superior to those of Sn-Pb solder. However, other problems still persist. The solution to overcoming these drawbacks is to add a small amount of alloying elements (Bi, Ag, Cr, Cu, and Sb to the Sn-Zn alloys. Microstructure, tensile strength, and hardness of the selected Sn-Zn-Bi ternary alloys have been investigated in this study. The SEM-EDS was used for the identification of co-existing phases in the samples. The specimens’ microstructures are composed of three phases: Sn-rich solid solution as the matrix, Bi-phase and Zn-rich phase. The Bi precipitates are formed around the Sn-dendrit grains as well as around the Zn-rich phase. The amount of Bi segregation increases with the increase of Bi content. The Sn-Zn-Bi alloys exhibit the high tensile strength and hardness, but the values of these mechanical properties decrease with the increase of Bi content, as well as the reduction of Zn content. The results presented in this paper may offer further knowledge of the effects various parameters have on the properties of lead-free Sn-Zn-Bi solders.

  3. levels of heavy metals in gubi dam water bauchi, nigeria

    African Journals Online (AJOL)

    Ada

    rivers to the ocean is in the form of particulate ... B.M. Wufem, Chemistry Programme, Abubakar Tafawa Balewa University, P.M.B. 0248, Bauchi. A.Q. Ibrahim ..... Chemistry. Wiley Interscience NY, p. 780. Sukiman, S.B., 1989. The determination of heavy metals in water, suspended materials and sediments from Langat River,.

  4. High-Current GaSb/InAs(Sb) Nanowire Tunnel Field-Effect Transistors

    OpenAIRE

    Dey, Anil; Borg, Mattias; Ganjipour, Bahram; Ek, Martin; Dick Thelander, Kimberly; Lind, Erik; Thelander, Claes; Wernersson, Lars-Erik

    2013-01-01

    We present electrical characterization of GaSb/InAs(Sb) nanowire tunnel field-effect transistors. The broken band alignment of the GaSb/InAs(Sb) heterostructure is exploited to allow for interband tunneling without a barrier, leading to high ON-current levels. We report a maximum drive current of 310 μA/μm at Vds = 0.5 V. Devices with scaled gate oxides display transconductances up to gm = 250 mS/mm at Vds = 300 mV, which are normalized to the nanowire circumference at the axial heterojunction...

  5. IR cut filters for optoelectronic devices, based on CdSb, ZnSb single crystals

    Directory of Open Access Journals (Sweden)

    Ashcheulov A. A.

    2009-02-01

    Full Text Available Interference-adsorptive filters on the base of the CdSb and ZnSb semiconductor single crystals are proposed as a new type of cooling cut optical filters used in modern optoelectronics. Computer simulation of the structure of interference multilayer coatings has shown the availability of design and application of cut filters on CdSb with optimized parameters. Experimental results demonstrate high optical characteristics and mechanical strength of two-channel cut CdSb filters used in various devices.

  6. The influence of boron addtion on structural, magnetic and thermoelectric properties of Ni2Mn1.52Sb0.48Bx

    DEFF Research Database (Denmark)

    Van Nong, Ngo; Le, Thanh Hung; Tuan Tai, Luu

    Heusler alloys known as X2YZ (full­-Heusler) and XYZ (half-­Hersler), where X and Y denote the transition metals and X is s-­p such as Al, Ga, Sb, Sn, In, ect., have been extensively studied since they possess many important properties [1-­3] like shape memory effect, magnetocaloric effect (MCE...

  7. Nuclear-spectroscopic studies in the {sup 132}Sn region; Kernspektroskopische Untersuchungen in der {sup 132}Sn-Region

    Energy Technology Data Exchange (ETDEWEB)

    Arndt, Oliver

    2007-10-15

    In this work investigations on r-process nuclides around the N = 82 shell closure are done. The so far unknown half-lives and P{sub n}-values of {sup 137-139}Sb and {sup 139}Te and their impact to r-process theory are given. Further the results of Shergur et. al. of neutron rich tin ({sup 137,138}Sn) are verified and in some points improved. New data on {gamma}-decay spectroscopy for {sup 136}Sn from single spectra is published. To improve beam quality and solve long known problems on ISOL-facilities with isobaric contamination, new techniques are discussed. A special focus is on molecular sidebands, which is first time adapted to a target/ion source unit in a mass separation facility. It was possible to create a strong SnS{sup +} sideband and in this way to reduce isobaric background with good beam intensities. On the other hand, a target with temperature controlled transfer line was build and its characteristics are discussed. To improve selectivity of a given experiment on neutron rich nuclei a new detector system for n{gamma}-coincidences was developed. Due to a special electronically setup of the new system it was possible to downsize the coincidence window compared to earlier attempts. (orig.)

  8. InSb semiconductors and (In,Mn)Sb diluted magnetic semiconductors. Growth and properties

    Energy Technology Data Exchange (ETDEWEB)

    Tran, Lien

    2011-04-13

    This dissertation describes investigations of the growth by molecular beam epitaxy and the characterization of the semiconductor InSb as well as the diluted magnetic semiconductor (DMS) In{sub 1-x}Mn{sub x}Sb. The InSb films were grown on GaAs (001) substrate and Si (001) offcut by 4 toward (110) substrate up to a thickness of about 2 {mu}m, in spite of a large lattice mismatch between the epi-layer and substrate (14.6% between InSb and GaAs, and 19.3% between InSb and Si). After optimizing the growth conditions, the best InSb films grown directly on GaAs without any special technique results in a high crystal quality, low noise, and an electron mobility of 41100 cm{sup 2}/V s Vs with associated electron concentration of 2.9.10{sup 6} cm{sup -3} at 300 K. Such structures could be used, for example, for infrared detector structures. The growth of InSb on Si, however, is a challenge. In order to successfully grow InSb on Si, tilted substrates and the insertion of buffer layers were used, which helps to reduce the lattice mismatch as well as the formation of defects, and hence to improve the crystal quality. An electron mobility of 24000 cm{sup 2}/V s measured at 300 K, with an associated carrier concentration of 2.6.10{sup 1}6 cm{sup -3} is found for the best sample that was grown at 340 C with a 0.06 {mu}m-thick GaSb/AlSb superlattice buffer layer. The smaller value of electron mobility (compared to the best GaAsbased sample) is related to a higher density of microtwins and stacking faults as well as threading dislocations in the near-interface region as shown by transmission electron microscopy. Deep level noise spectra indicate the existence of deep levels in both GaAs and Si-based samples. The samples grown on Si exhibit the lowest Hooge factor at 300 K, lower than the samples grown on GaAs. Taking the optimized growth conditions of InSb/GaAs, the diluted magnetic semiconductor In{sub 1-x}Mn{sub x}Sb/GaAs (001) is prepared by adding a few percent of Mn into the

  9. Heavy metals biogeochemistry in abandoned mining areas

    Directory of Open Access Journals (Sweden)

    Favas P. J. C.

    2013-04-01

    Full Text Available Plants growing on the abandoned Portuguese mines, highly contaminated with W, Sn, As, Cd, Cu, Zn and Pb, have been studied for their biogeochemical indication/prospecting and mine restoration potential. The results of analysis show that the species best suited for biogeochemical indicating are: aerial tissues of Halimium umbellatum (L. Spach, for As and W; leaves of Erica arborea L. for Bi, Sn, W and mostly Pb; stems of Erica arborea L. for Pb; needles of Pinus pinaster Aiton and aerial tissues of Pteridium aquilinum (L. Kuhn for W; and leaves of Quercus faginea Lam. for Sn. The aquatic plant studied (Ranunculus peltatus Schrank can be used to decrease the heavy metals, and arsenic amounts into the aquatic environment affected by acid mine drainages.

  10. Polarity-dependent resistance switching in GeSbTe phase-change thin films : The importance of excess Sb in filament formation

    NARCIS (Netherlands)

    Pandian, Ramanathaswamy; Kooi, Bart J.; Oosthoek, Jasper L. M.; van den Dool, Pim; Palasantzas, George; Pauza, Andrew

    2009-01-01

    We show that polarity-dependent resistance switching in GeSbTe thin films depends strongly on Sb composition by comparing current-voltage characteristics in Sb-excess Ge(2)Sb(2+x)Te(5) and stoichiometric Ge(2)Sb(2)Te(5) samples. This type of switching in Ge(2)Sb(2+x)Te(5) films is reversible with

  11. Electrostatic performance of InSb, GaSb, Si and Ge p-channel nanowires

    Science.gov (United States)

    Martinez-Blanque, C.; Marin, E. G.; Toral, A.; Gonzalez-Medina, J. M.; Ruiz, F. G.; Godoy, A.; Gámiz, F.

    2017-12-01

    The electrostatic performance of p-type nanowires (NWs) made of InSb and GaSb, with special focus on their gate capacitance behaviour, is analysed and compared to that achieved by traditional semiconductors usually employed for p-MOS such as Si and Ge. To do so, a self-consistent \

  12. Lattice location of the group V elements Sb, As, and P in ZnO

    CERN Document Server

    Wahl, Ulrich; Mendonça, Tânia; Decoster, Stefan

    2010-01-01

    Modifying the properties of ZnO by means of incorporating antimony, arsenic or phosphorus impurities is of interest since these group V elements have been reported in the literature among the few successful p-type dopants in this technologically promising II-VI compound. The lattice location of ion-implanted Sb, As, and P in ZnO single crystals was investigated by means of the electron emission channeling technique using the radioactive isotopes $^{124}$Sb, $^{73}$As and $^{33}$P and it is found that they preferentially occupy substitutional Zn sites while the possible fractions on substitutional O sites are a few percent at maximum. The lattice site preference is understandable from the relatively large ionic size of the heavy mass group V elements. Unfortunately the presented results cannot finally settle the interesting issue whether substitutional Sb, As or P on oxygen sites or Sb$_{Zn}$−2V$_{Zn}$, As$_{Zn}$−2V$_{Zn}$ or P$_{Zn}$−2V$_{Zn}$ complexes (as suggested in the literature) are responsible f...

  13. DWPF simulant CPC studies for SB8

    Energy Technology Data Exchange (ETDEWEB)

    Koopman, D. C.; Zamecnik, J. R.

    2013-06-25

    The Savannah River National Laboratory (SRNL) accepted a technical task request (TTR) from Waste Solidification Engineering to perform simulant tests to support the qualification of Sludge Batch 8 (SB8) and to develop the flowsheet for SB8 in the Defense Waste Processing Facility (DWPF). These efforts pertained to the DWPF Chemical Process Cell (CPC). Separate studies were conducted for frit development and glass properties (including REDOX). The SRNL CPC effort had two primary phases divided by the decision to drop Tank 12 from the SB8 constituents. This report focuses on the second phase with SB8 compositions that do not contain the Tank 12 piece. A separate report will document the initial phase of SB8 testing that included Tank 12. The second phase of SB8 studies consisted of two sets of CPC studies. The first study involved CPC testing of an SB8 simulant for Tank 51 to support the CPC demonstration of the washed Tank 51 qualification sample in the SRNL Shielded Cells facility. SB8-Tank 51 was a high iron-low aluminum waste with fairly high mercury and moderate noble metal concentrations. Tank 51 was ultimately washed to about 1.5 M sodium which is the highest wash endpoint since SB3-Tank 51. This study included three simulations of the DWPF Sludge Receipt and Adjustment Tank (SRAT) cycle and Slurry Mix Evaporator (SME) cycle with the sludge-only flowsheet at nominal DWPF processing conditions and three different acid stoichiometries. These runs produced a set of recommendations that were used to guide the successful SRNL qualification SRAT/SME demonstration with actual Tank 51 washed waste. The second study involved five SRAT/SME runs with SB8-Tank 40 simulant. Four of the runs were designed to define the acid requirements for sludge-only processing in DWPF with respect to nitrite destruction and hydrogen generation. The fifth run was an intermediate acid stoichiometry demonstration of the coupled flowsheet for SB8. These runs produced a set of processing

  14. Sonochemical preparation of SbSI gel.

    Science.gov (United States)

    Nowak, M; Szperlich, P; Bober, L; Szala, J; Moskal, G; Stróz, D

    2008-07-01

    A novel sonochemical method for direct preparation of nanocrystalline antimony sulfoiodide (SbSI) has been established. The SbSI gel was synthesized using elemental Sb, S and I in the presence of ethanol under ultrasonic irradiation (35 kHz, 2 W/cm2) at 50 degrees C for 2 h. The products were characterized by using techniques such as powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), and optical diffuse reflection spectroscopy (DRS). The SEM and HRTEM investigations exhibit that the as-prepared samples are made up of large quantity nanowires with diameters of about 10-50 nm and lengths reaching up to several micrometers and single-crystalline in nature.

  15. Reduction in thermal conductivity of BiSbTe lump

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Kaleem [King Saud University, Sustainable Energy Technologies Center, College of Engineering, PO Box 800, Riyadh (Saudi Arabia); Wan, C. [Tsinghua University, State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Beijing (China); Al-Eshaikh, M.A.; Kadachi, A.N. [King Saud University, Research Center, College of Engineering, PO Box 800, Riyadh (Saudi Arabia)

    2017-03-15

    In this work, systematic investigations on the thermal conductivities of BiSbTe lump, microstructured pristine BiSbTe bulk and single wall carbon nanotubes (SWCNTs)/BiSbTe bulk nanocomposites were performed. BiSbTe lumps were crushed to form a coarse powder (200 μm) and effect of particle size reduction on the effective thermal conductivity of BiSbTe (200 μm) bulk were analyzed. For further reduction in the conductivity, a two pronged strategy has been employed. First, additional refinement of BiSbTe (200 μm) were performed through ball milling in an inert environment. Second, SWCNTs in 0.75, and 1.0 vol% were distributed uniformly in the fine BiSbTe ball milled powder. The results showed that the effective thermal conductivities decrease with the reduction in the particle size from lump to BiSbTe (200 μm) bulk as well as with the addition of SWCNTs accompanied by further refinement of BiSbTe particles. The significant reduction in thermal conductivities of the lump was achieved for pure BiSbTe (200 μm) bulk and 0.75 vol% of SWCNTs/BiSbTe composite. This can be ascribed to the enhanced phonon scattering by the grain boundaries between the nanostructured BiSbTe particles as well as the interfaces between BiSbTe and the low dimensional carbon nanotubes. (orig.)

  16. Peculiarities of thermoelectric half-Heusler phase formation in Gd-Ni-Sb and Lu-Ni-Sb ternary systems

    Energy Technology Data Exchange (ETDEWEB)

    Romaka, V.V., E-mail: romakav@lp.edu.ua [Department of Applied Material Science and Materials Engineering, Lviv Polytechnic National University, Ustyyanovycha Str. 5, 79013 Lviv (Ukraine); Romaka, L.; Horyn, A. [Inorganic Chemistry Department, Ivan Franko Lviv National University, Kyryla and Mefodiya str. 6, 79005 Lviv (Ukraine); Rogl, P. [Institute of Materials Chemistry and Research, University of Vienna, Währingerstrasse 42, A-1090 Wien (Austria); Stadnyk, Yu; Melnychenko, N. [Inorganic Chemistry Department, Ivan Franko Lviv National University, Kyryla and Mefodiya str. 6, 79005 Lviv (Ukraine); Orlovskyy, M.; Krayovskyy, V. [Department of Applied Material Science and Materials Engineering, Lviv Polytechnic National University, Ustyyanovycha Str. 5, 79013 Lviv (Ukraine)

    2016-07-15

    The phase equilibria in the Gd–Ni–Sb and Lu-Ni-Sb ternary systems were studied at 873 K by X-ray and metallographic analyses in the whole concentration range. The interaction of the elements in the Gd–Ni–Sb system results the formation of five ternary compounds at investigated temperature: Gd{sub 5}Ni{sub 2}Sb (Mo{sub 5}SiB{sub 2}-type), Gd{sub 5}NiSb{sub 2} (Yb{sub 5}Sb{sub 3}-type), GdNiSb (MgAgAs-type), Gd{sub 3}Ni{sub 6}Sb{sub 5} (Y{sub 3}Ni{sub 6}Sb{sub 5}-type), and GdNi{sub 0.72}Sb{sub 2} (HfCuSi{sub 2}-type). At investigated temperature the Lu-Ni-Sb system is characterized by formation of the LuNiSb (MgAgAs-type), Lu{sub 5}Ni{sub 2}Sb (Mo{sub 5}SiB{sub 2}-type), and Lu{sub 5}Ni{sub 0.56}Sb{sub 2.44} (Yb{sub 5}Sb{sub 3}-type) compounds. The disordering in the crystal structure of half-Heusler GdNiSb and LuNiSb was revealed by EPMA and studied by means of Rietveld refinement and DFT modeling. The performed electronic structure calculations are in good agreement with electrical transport property studies. - Graphical abstract: Crystal structure model and electron localization function of Lu{sub 5}Ni{sub 2}Sb. Display Omitted - Highlights: • Gd-Ni-Sb and Lu-Ni-Sb phase diagrams were constructed at 873 K. • GdNiSb and LuNiSb are characterized by disordered crystal structure. • Crystal structure optimization with DFT calculations confirmed crystal structure disorder in GdNiSb and LuNiSb.

  17. Adsorption of Sb(III) and Sb(V) on Freshly Prepared Ferric Hydroxide (FeOxHy).

    Science.gov (United States)

    He, Zan; Liu, Ruiping; Liu, Huijuan; Qu, Jiuhui

    2015-02-01

    This study prepared fresh ferric hydroxide (in-situ FeOxHy) by the enhanced hydrolysis of Fe3+ ions, and investigates its adsorptive behaviors toward Sb(III) and Sb(V) through laboratory and pilot-scale studies. A contact time of 120-min was enough to achieve adsorption equilibrium for Sb(III) and Sb(V) on the in-situ FeOxHy, and the Elovich model was best to describe the adsorption kinetics of Sb(III) and Sb(V). The Freundlich model was better than Langmuir model to describe the adsorption of Sb(III) and Sb(V) on the in-situ FeOxHy, and the maximum adsorption capacity of Sb(III) and Sb(V) was determined to be 12.77 and 10.21 mmol/g the in-situ FeOxHy as Fe, respectively. Adsorption of Sb(V) decreased whereas that of Sb(III) increased with elevated pH over pH 3-10, owing to the different electrical properties of Sb(III) and Sb(V). Adsorption of Sb(III) and Sb(V) was slightly affected by ionic strength, and thus indicated the formation of inner sphere complexes between Sb and the adsorbent. Sulfate and carbonate showed little effect on the adsorption of Sb(III) and Sb(V). Phosphate significantly inhibited the adsorption of Sb(V), whereas slightly effected that of Sb(III) due to its similar chemical structure to Sb(V). Pilot-scale continuous experiment indicated the feasibility of using in-situ FeOxHy to remove Sb(V), and equilibrium adsorption capacity at the equilibrium Sb(V) concentration of 10 μg/L was determined to be 0.11, 0.07, 0.07, 0.11, and 0.12 mg/g the in-situ FeOxHy as Fe at equilibrium pH of 7.5-7.7, 6.9-7.0, 6.3-6.6, 5.9-6.4, and 5.2-5.9, respectively.

  18. Excitation spectrum of PrOs{sub 4}Sb{sub 12} under a magnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Raymond, S; Flouquet, J [CEA-DSM/INAC/SPSMS, F-38054 Grenoble (France); Kuwahara, K [Institute of Applied Beam Science, Ibaraki University, Mito 310-8512 (Japan); Kaneko, K; Metoki, N [ASRC, Japan Atomic Energy Agency, Ibaraki 319-1195 (Japan); Iwasa, K [Department of Physics, Tohoku University, Sendai 980-8578 (Japan); Kohgi, M; Aoki, Y; Sato, H [Department of Physics, Tokyo Metropolitan University, Tokyo 192-0397 (Japan); Hiess, A [Institut Laue Langevin, F-38042 Grenoble Cedex (France); Sugawara, H [Faculty of Integrated Arts and Science, University of Tokushima, Tokushima 770-8502 (Japan)

    2009-05-27

    The evolution of the magnetic excitation spectrum of the heavy fermion superconductor PrOs{sub 4}Sb{sub 12} was studied by inelastic neutron scattering on crossing the critical field H{sub c2} for superconductivity at low temperature. The peak positions in energy and the peak intensities of the modes of the triplet split by magnetic field confirm the known crystal field parameters for PrOs{sub 4}Sb{sub 12} in T{sub h} symmetry. A selective broadening of the lineshape occurs on increasing the magnetic field: the linewidth of the upper mode of the triplet increases while the one of the middle mode does not.

  19. Heavy metal

    African Journals Online (AJOL)

    niloticus after exposure to sublethal concentrations of heavy metals such as copper, lead and zinc for a 12-week period, using static renewable toxicity tests. The concentrations of the metals accumulated in the tissue of exposed fish were about 3-5 times higher than the concentrations detected in control fish.

  20. Menorrhagia (Heavy Menstrual Bleeding)

    Science.gov (United States)

    Menorrhagia (heavy menstrual bleeding) Overview Menorrhagia is the medical term for menstrual periods with abnormally heavy or prolonged bleeding. Although heavy menstrual bleeding is a common concern, ...

  1. Structures of tin cluster cations Sn3(+) to Sn15(+).

    Science.gov (United States)

    Drebov, Nedko; Oger, Esther; Rapps, Thomas; Kelting, Rebecca; Schooss, Detlef; Weis, Patrick; Kappes, Manfred M; Ahlrichs, Reinhart

    2010-12-14

    We employ a combination of ion mobility measurements and an unbiased systematic structure search with density functional theory methods to study structure and energetics of gas phase tin cluster cations, Sn(n)(+), in the range of n = 3-15. For Sn(13)(+) we also carry out trapped ion electron diffraction measurements to ascertain the results obtained by the other procedures. The structures for the smaller systems are most easily described by idealized point group symmetries, although they are all Jahn-Teller distorted: D(3h) (trigonal bipyramid), D(4h) (octahedron), D(5h) (pentagonal bipyramid) for n = 5, 6, and 7. For the larger systems we find capped D(5h) for Sn(8)(+) and Sn(9)(+), D(3h) (tricapped trigonal prism) and D(4d) (bicapped squared antiprism) plus adatoms for n = 10, 11, 14, and 15. A centered icosahedron with a peripheral atom removed is the dominant motif in Sn(12)(+). For Sn(13)(+) the calculations predict a family of virtually isoenergetic isomers, an icosahedron and slightly distorted icosahedra, which are about 0.25 eV below two C(1) structures. The experiments indicate the presence of two structures, one from the I(h) family and a prolate C(1) isomer based on fused deltahedral moieties.

  2. Adsorption study of Pb 2 ions on nanosized SnO2, synthesized by ...

    Indian Academy of Sciences (India)

    propagating combustion reaction ... Novel combustion synthetic route for the synthesis of nanosized SnO2 is reported. X-ray, tap and ... The potential use of solid adsorbents for the adsorption of heavy metal pollutants is envisaged in the present work.

  3. Spin gap and antiferromagnetic correlations in the kondo insulator CeNiSn

    DEFF Research Database (Denmark)

    Mason, T.E.; Aeppli, G.; Ramirez, A.P.

    1992-01-01

    Neutron scattering measurements show that the crossover (at T less than or similar to 10 K) from metallic heavy-fermion to semiconducting behavior coincides with the formation of a gap in the magnetic excitation spectrum of CeNiSn. In contrast to the simple band picture of an insulator, the gap...

  4. The effects of doping on the structural, optical and electric properties of Zn4Sb3 material

    Directory of Open Access Journals (Sweden)

    Vaida Mirela

    2016-01-01

    Full Text Available This paper presents results of the investigations regarding the obtaining and the characterization of the thermoelectric material Zn4Sb3 and (Zn1-xMx4Sb3 where M = Ag and / or Sn. Obtaining of the materials was realized by melting high purity precursors into an oven where were kept isothermally for 12 hours at 1173 K. X-ray diffraction and scanning electron microscopy were used for structural and morphologic characterization. Optical band gap for each sample was determined from absorbance spectra recorded in the visible range 240-400 nm at room temperature. Electrical resistivity as function of temperature was measured and the electrical band gap was estimated for each of the obtained samples. The semiconducting behavior of the materials was reflected by these.

  5. GaAs/GaSb nanowire heterostructures grown by MOVPE

    DEFF Research Database (Denmark)

    Jeppsson, Mattias; Dick, Kimberly A.; Wagner, Jakob Birkedal

    2008-01-01

    to most other III–V nanowire systems, the GaSb nanowire growth is Group V-limited under most conditions. We found that depending on the TMSb molar fraction, the seed particle is either supersaturated AuGa or AuGa2 during GaSb growth. The high Ga content in the particle gives a characteristic diameter...... increase between the GaAs and GaSb segment. From TEM and XEDS measurements we conclude that the GaSb nanowire growth occurs along either the AuGa–GaSb or AuGa2–GaSb pseudo-binaries of the Au–Ga–Sb ternary phase diagram. Finally, the GaSb nanowires exhibit untapered radial growth on the {1 1¯ 0} side facets....

  6. Highly efficient electrochemical degradation of perfluorooctanoic acid (PFOA) by F-doped Ti/SnO{sub 2} electrode

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Bo, E-mail: boyang@szu.edu.cn [Department of Environmental Engineering, College of Chemistry and Chemical Engineering, Shenzhen University, Shenzhen 518060 (China); School of Environment, POPs Research Center, Tsinghua University, Beijing 100084 (China); Jiang, Chaojin [Department of Environmental Engineering, College of Chemistry and Chemical Engineering, Shenzhen University, Shenzhen 518060 (China); Yu, Gang, E-mail: yg-den@tsinghua.edu.cn [School of Environment, POPs Research Center, Tsinghua University, Beijing 100084 (China); Zhuo, Qiongfang [South China Institute of Environmental Sciences, The Ministry of Environment Protection, Guangzhou 510655 (China); Deng, Shubo [School of Environment, POPs Research Center, Tsinghua University, Beijing 100084 (China); Wu, Jinhua [School of Environment and Energy, South China University of Technology, Guangzhou 510006 (China); Zhang, Hong [Department of Environmental Engineering, College of Chemistry and Chemical Engineering, Shenzhen University, Shenzhen 518060 (China)

    2015-12-15

    Highlights: • A novel SnO{sub 2} electrode is prepared by F doping instead of the traditional Sb doping. • SnF{sub 4} as single-source precursor is used to fabricate the long-life Ti/SnO{sub 2}–F anode. • F-doped Ti/SnO{sub 2} anode possesses high OEP and decomposition ability for PFOA. • Further mechanistic detail of PFOA degradation on Ti/SnO{sub 2}–F electrode is proposed. - Abstract: The novel F-doped Ti/SnO{sub 2} electrode prepared by SnF{sub 4} as the single-source precursor was used for electrochemical degradation of aqueous perfluorooctanoic acid (PFOA). Higher oxidation reactivity and significantly longer service life were achieved for Ti/SnO{sub 2}–F electrode than Ti/SnO{sub 2}–X (X = Cl, Br, I, or Sb) electrode, which could decomposed over 99% of PFOA (50 mL of 100 mg L{sup −1}) within 30-min electrolysis. The property of Ti/SnO{sub 2}–F electrode and its electrooxidation mechanism were investigated by XRD, SEM–EDX, EIS, LSV, and interfacial resistance measurements. We propose that the similar ionic radii of F and O as well as strong electronegativity of F caused its electrochemical stability with high oxygen evolution potential (OEP) and smooth surface to generate weakly adsorbed ·OH. The preparation conditions of electrode were also optimized including F doping amount, calcination temperature, and dip coating times, which revealed the formation process of electrode. Additionally, the major mineralization product, F{sup −}, and low concentration of shorter chain perfluorocarboxylic acids (PFCAs) were detected in solution. So the reaction pathway of PFOA electrooxidation was proposed by intermediate analysis. These results demonstrate that Ti/SnO{sub 2}–F electrode is promising for highly efficient treatment of PFOA in wastewater.

  7. Extra-low thermal conductivity in unfilled CoSb3-δ skutterudite synthesized under high-pressure conditions

    Science.gov (United States)

    Prado-Gonjal, J.; Serrano-Sánchez, F.; Nemes, N. M.; Dura, O. J.; Martínez, J. L.; Fernández-Díaz, M. T.; Fauth, F.; Alonso, J. A.

    2017-08-01

    Thermoelectric CoSb3-δ skutterudite was synthesized and sintered in one step under high-pressure conditions at 3.5 GPa in a piston-cylinder hydrostatic press. Structural analysis carried out from synchrotron x-ray powder diffraction data reveals a significant Sb deficiency in this material. The introduction of point defects in the form of Sb vacancies distributed at random in the structure leads to an impressive reduction (>50%) of the total thermal conductivity, κ, which is one of the main ingredients of good thermoelectric materials. This suggests phonon scattering effects originated in the Sb defects, which drives to a better improvement in κ than that achieved by the conventional strategy of filling the cages of the skutterudite structure with rare earths or other heavy cations. In parallel, changes in the electronic band structure caused by point variation of the stoichiometry produce an undesired increment in the electrical resistivity. Nevertheless, the low thermal conductivity combined with a high Seebeck coefficient (-434 μV K-1 at 500 K) originates a relatively large figure of merit (ZT = 0.12 at 550 K) for CoSb2.90(2).

  8. Sulfuric Acid Corrosion of Low Sb - Pb Battery Alloys | Ntukogu ...

    African Journals Online (AJOL)

    The corrosion properties of low Sb - Pb alloys developed for maintenance free motive power industrial batteries was studied by a bare grid constant current method and compared to those of the conventional Pb- 6% Sb alloy. Low Sb-Pb alloys with Se and As grain refiners were found to have higher corrosion rates than the ...

  9. A yield-optimized access to double-helical SnIP via a Sn/SnI2 approach

    Science.gov (United States)

    Utrap, André; Xiang, Ng Yan; Nilges, Tom

    2017-10-01

    Herein we report on the optimized synthesis process of SnIP, the first inorganic double helix compound which shows high mechanical flexibility, a strong tendency for cleavage or delamination and intriguing electronic properties. In this work we analyzed the influence of SnI2 as a reaction promotor or mineralizer compound for the synthesis of SnIP. In previous studies Sn/SnI4 was used as a precursor and chemical transport agent for the SnIP synthesis but significant amounts of non-reacted tin halide (SnI2 and SnI4) remained after the formation of the target compound reducing its quality and yield. Significantly less tin halide residue can be observed which suggests a reduction of side-reactions. While the Sn/SnI4 couple works perfectly for the synthesis of the two-dimensional material phosphorene precursor black phosphorus the Sn/SnI2 couple is beneficial for the one-dimensional ternary polyphosphide SnIP. These results strongly encourage the theory of SnI2 as the important reaction intermediate in the synthesis of covalently-bonded polyphosphide substructures and element allotropes at elevated temperatures.

  10. [The corrosion behavior of antimony in a Ag-Sn-Cu-Sb amalgam].

    Science.gov (United States)

    Weiland, M; Borrmann, S; Nossek, H

    1989-01-01

    Specimen of amalgam containing antimony were stored in solutions with different pH and different content of rhodanide until 21 days. The most antimony were solved within 24 hours. After 7 days an increase of the antimony concentration were not observed in physiological pH. An inhibition of corrosion by rhodanide existed only after incubation from 21 days. The quantity of antimony (10-21 micrograms) were analysed by mean of atomic absorption spectroscopy. It represent not a risk for the health. The natural presence of this element in environment and in human body is discussed to the analysed quantity of solved antimony.

  11. The fire ant social chromosome supergene variant Sb shows low diversity but high divergence from SB

    OpenAIRE

    Pracana, Rodrigo; Priyam, Anurag; Levantis, Ilya; Nichols, Richard A.; Wurm, Yannick

    2017-01-01

    Abstract Variation in social behaviour is common, yet little is known about the genetic architectures underpinning its evolution. A rare exception is in the fire ant Solenopsis invicta: Alternative variants of a supergene region determine whether a colony will have exactly one or up to dozens of queens. The two variants of this region are carried by a pair of ?social chromosomes?, SB and Sb, which resemble a pair of sex chromosomes. Recombination is suppressed between the two chromosomes in t...

  12. Determination of traces of Sb(III) using ASV in Sb-rich water samples affected by mining

    Energy Technology Data Exchange (ETDEWEB)

    Cidu, Rosa, E-mail: cidur@unica.it; Biddau, Riccardo; Dore, Elisabetta

    2015-01-07

    Highlights: • Antimony speciation affects the toxicity of this element. • A simple method for Sb(III) analyses in Sb-rich waters was developed. • Sb(III) was determined by ASV in water stabilized with tartaric and nitric acids. • Pre-concentration and/or separation of Sb(III) prior to analysis are not required. - Abstract: Chemical speciation [Sb(V) and Sb(III)] affects the mobility, bioavailability and toxicity of antimony. In oxygenated environments Sb(V) dominates whereas thermodynamically unstable Sb(III) may occur. In this study, a simple method for the determination of Sb(III) in non acidic, oxygenated water contaminated with antimony is proposed. The determination of Sb(III) was performed by anodic stripping voltammetry (ASV, 1–20 μg L{sup −1} working range), the total antimony, Sb(tot), was determined either by inductively coupled plasma mass spectrometry (ICP-MS, 1–100 μg L{sup −1} working range) or inductively coupled plasma optical emission spectrometry (ICP-OES, 100–10,000 μg L{sup −1} working range) depending on concentration. Water samples were filtered on site through 0.45 μm pore size filters. The aliquot for determination of Sb(tot) was acidified with 1% (v/v) HNO{sub 3}. Different preservatives, namely HCl, L(+) ascorbic acid or L(+) tartaric acid plus HNO{sub 3}, were used to assess the stability of Sb(III) in synthetic solutions. The method was tested on groundwater and surface water draining the abandoned mine of Su Suergiu (Sardinia, Italy), an area heavily contaminated with Sb. The waters interacting with Sb-rich mining residues were non acidic, oxygenated, and showed extreme concentrations of Sb(tot) (up to 13,000 μg L{sup −1}), with Sb(III) <10% of total antimony. The stabilization with L(+) tartaric acid plus HNO{sub 3} appears useful for the determination of Sb(III) in oxygenated, Sb-rich waters. Due to the instability of Sb(III), analyses should be carried out within 7 days upon the water collection. The main

  13. Lower lattice thermal conductivity in SbAs than As or Sb monolayers: a first-principles study.

    Science.gov (United States)

    Guo, San-Dong; Liu, Jiang-Tao

    2017-12-06

    Phonon transport in group-VA element (As, Sb and Bi) monolayer semiconductors has been widely investigated in theory, and, of them, monolayer Sb (antimonene) has recently been synthesized. In this work, phonon transport in monolayer SbAs is investigated with a combination of first-principles calculations and the linearized phonon Boltzmann equation. It is found that the lattice thermal conductivity of monolayer SbAs is lower than those of both monolayer As and Sb, and the corresponding sheet thermal conductance is 28.8 W K-1 at room temperature. To understand the lower lattice thermal conductivity in monolayer SbAs than those in monolayer As and Sb, the group velocities and phonon lifetimes of monolayer As, SbAs and Sb are calculated. The calculated results show that the group velocities of monolayer SbAs are between those of monolayer As and Sb, but that the phonon lifetimes of SbAs are smaller than those of both monolayer As and Sb. Hence, the low lattice thermal conductivity in monolayer SbAs is attributed to very small phonon lifetimes. Unexpectedly, the ZA branch has very little contribution to the total thermal conductivity, only 2.4%, which is obviously different from those of monolayer As and Sb with very large contributions. This can be explained by very small phonon lifetimes for the ZA branch of monolayer SbAs. The lower lattice thermal conductivity of monolayer SbAs compared to that of monolayer As or Sb can be understood by the alloying of As (Sb) with Sb (As), which should introduce phonon point defect scattering. We also consider the isotope and size effects on the lattice thermal conductivity. It is found that isotope scattering produces a neglectful effect, and the lattice thermal conductivity with a characteristic length smaller than 30 nm can reach a decrease of about 47%. These results may offer perspectives on tuning the lattice thermal conductivity by the mixture of multiple elements for applications of thermal management and thermoelectricity

  14. Observation of Spin Relaxation in InGaAs/AlAsSb Quantum Wells

    Science.gov (United States)

    Sotaro Izumi,; Shin-Ichiro Gozu,; Teruo Mozume,; Yu Saeki,; Takao Nukui,; Atsushi Tackeuchi,

    2010-04-01

    We have investigated the exciton spin relaxation in InGaAs/AlAsSb quantum wells using time-resolved spin-dependent pump and probe reflectance measurements. The spin relaxation time of 1.46 μm electron-heavy hole excitons at room temperature is obtained to be 27-54 ps for an excitation power of 20-100 mW. The carrier density dependence of the exciton spin relaxation time was clearly observed, suggesting that the spin relaxation mechanism is strongly related to the Bir-Aronov-Pikus process at room temperature.

  15. Carrier spin relaxation in InGaAs/AlAsSb quantum wells

    Science.gov (United States)

    Nukui, T.; Gozu, S.; Mozume, T.; Izumi, S.; Saeki, Y.; Tackeuchi, A.

    2011-12-01

    We have investigated the exciton spin relaxation in InGaAs/AlAsSb quantum wells by time-resolved spin-dependent pump and probe reflectance measurements. The spin relaxation time of 1.38 μm-electron-heavy-hole excitons at 150 K is obtained to be 34-43 ps at an excitation power of 50-80 mW. The observed carrier density dependence and temperature independence of the spin relaxation time indicate that the spin relaxation mechanism is dominated by the Bir-Aronov-Pikus process.

  16. Forced convection by Inclined Rotary Bridgman method for growth of CoSb3 and FeSb2 single crystals from Sb-rich solutions

    Science.gov (United States)

    Pillaca, Mirtha; Harder, Oliver; Miller, Wolfram; Gille, Peter

    2017-10-01

    Sb-based compounds such as CoSb3 and FeSb2 are interesting materials for thermoelectric applications. Their single crystal growth can be achieved from high-temperature solutions that are strongly enriched in Sb. In Bridgman growth using closed ampoules, effective mixing of the solution is an important prerequisite in order to minimize the high risk of liquid inclusion formation. We have successfully grown inclusion-free single crystal of CoSb3 and FeSb2 by rotating the ampoule in a Bridgman-type crystal growth set-up being inclined by 75° with respect to the vector of gravity. Numerical modelling as well as experimental growth studies have demonstrated the strong influence of forced convection that is achieved by this modified directional solidification technique called Inclined Rotary Bridgman method.

  17. Sorghum Phytochrome B Inhibits Flowering in Long Days by Activating Expression of SbPRR37 and SbGHD7, Repressors of SbEHD1, SbCN8 and SbCN12

    Science.gov (United States)

    Yang, Shanshan; Murphy, Rebecca L.; Morishige, Daryl T.; Klein, Patricia E.; Rooney, William L.; Mullet, John E.

    2014-01-01

    Light signaling by phytochrome B in long days inhibits flowering in sorghum by increasing expression of the long day floral repressors PSEUDORESPONSE REGULATOR PROTEIN (SbPRR37, Ma1) and GRAIN NUMBER, PLANT HEIGHT AND HEADING DATE 7 (SbGHD7, Ma6). SbPRR37 and SbGHD7 RNA abundance peaks in the morning and in the evening of long days through coordinate regulation by light and output from the circadian clock. 58 M, a phytochrome B deficient (phyB-1, ma3R) genotype, flowered ∼60 days earlier than 100 M (PHYB, Ma3) in long days and ∼11 days earlier in short days. Populations derived from 58 M (Ma1, ma3R, Ma5, ma6) and R.07007 (Ma1, Ma3, ma5, Ma6) varied in flowering time due to QTL aligned to PHYB/phyB-1 (Ma3), Ma5, and GHD7/ghd7-1 (Ma6). PHYC was proposed as a candidate gene for Ma5 based on alignment and allelic variation. PHYB and Ma5 (PHYC) were epistatic to Ma1 and Ma6 and progeny recessive for either gene flowered early in long days. Light signaling mediated by PhyB was required for high expression of the floral repressors SbPRR37 and SbGHD7 during the evening of long days. In 100 M (PHYB) the floral activators SbEHD1, SbCN8 and SbCN12 were repressed in long days and de-repressed in short days. In 58 M (phyB-1) these genes were highly expressed in long and short days. Furthermore, SbCN15, the ortholog of rice Hd3a (FT), is expressed at low levels in 100 M but at high levels in 58 M (phyB-1) regardless of day length, indicating that PhyB regulation of SbCN15 expression may modify flowering time in a photoperiod-insensitive manner. PMID:25122453

  18. Sorghum phytochrome B inhibits flowering in long days by activating expression of SbPRR37 and SbGHD7, repressors of SbEHD1, SbCN8 and SbCN12.

    Directory of Open Access Journals (Sweden)

    Shanshan Yang

    Full Text Available Light signaling by phytochrome B in long days inhibits flowering in sorghum by increasing expression of the long day floral repressors PSEUDORESPONSE REGULATOR PROTEIN (SbPRR37, Ma1 and GRAIN NUMBER, PLANT HEIGHT AND HEADING DATE 7 (SbGHD7, Ma6. SbPRR37 and SbGHD7 RNA abundance peaks in the morning and in the evening of long days through coordinate regulation by light and output from the circadian clock. 58 M, a phytochrome B deficient (phyB-1, ma3R genotype, flowered ∼60 days earlier than 100 M (PHYB, Ma3 in long days and ∼11 days earlier in short days. Populations derived from 58 M (Ma1, ma3R, Ma5, ma6 and R.07007 (Ma1, Ma3, ma5, Ma6 varied in flowering time due to QTL aligned to PHYB/phyB-1 (Ma3, Ma5, and GHD7/ghd7-1 (Ma6. PHYC was proposed as a candidate gene for Ma5 based on alignment and allelic variation. PHYB and Ma5 (PHYC were epistatic to Ma1 and Ma6 and progeny recessive for either gene flowered early in long days. Light signaling mediated by PhyB was required for high expression of the floral repressors SbPRR37 and SbGHD7 during the evening of long days. In 100 M (PHYB the floral activators SbEHD1, SbCN8 and SbCN12 were repressed in long days and de-repressed in short days. In 58 M (phyB-1 these genes were highly expressed in long and short days. Furthermore, SbCN15, the ortholog of rice Hd3a (FT, is expressed at low levels in 100 M but at high levels in 58 M (phyB-1 regardless of day length, indicating that PhyB regulation of SbCN15 expression may modify flowering time in a photoperiod-insensitive manner.

  19. PROTEUS-SN User Manual

    Energy Technology Data Exchange (ETDEWEB)

    Shemon, Emily R. [Argonne National Lab. (ANL), Argonne, IL (United States); Smith, Micheal A. [Argonne National Lab. (ANL), Argonne, IL (United States); Lee, Changho [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-02-16

    PROTEUS-SN is a three-dimensional, highly scalable, high-fidelity neutron transport code developed at Argonne National Laboratory. The code is applicable to all spectrum reactor transport calculations, particularly those in which a high degree of fidelity is needed either to represent spatial detail or to resolve solution gradients. PROTEUS-SN solves the second order formulation of the transport equation using the continuous Galerkin finite element method in space, the discrete ordinates approximation in angle, and the multigroup approximation in energy. PROTEUS-SN’s parallel methodology permits the efficient decomposition of the problem by both space and angle, permitting large problems to run efficiently on hundreds of thousands of cores. PROTEUS-SN can also be used in serial or on smaller compute clusters (10’s to 100’s of cores) for smaller homogenized problems, although it is generally more computationally expensive than traditional homogenized methodology codes. PROTEUS-SN has been used to model partially homogenized systems, where regions of interest are represented explicitly and other regions are homogenized to reduce the problem size and required computational resources. PROTEUS-SN solves forward and adjoint eigenvalue problems and permits both neutron upscattering and downscattering. An adiabatic kinetics option has recently been included for performing simple time-dependent calculations in addition to standard steady state calculations. PROTEUS-SN handles void and reflective boundary conditions. Multigroup cross sections can be generated externally using the MC2-3 fast reactor multigroup cross section generation code or internally using the cross section application programming interface (API) which can treat the subgroup or resonance table libraries. PROTEUS-SN is written in Fortran 90 and also includes C preprocessor definitions. The code links against the PETSc, METIS, HDF5, and MPICH libraries. It optionally links against the MOAB library and

  20. Laser processing issues of nanosized intermetallic Fe-Sn and metallic Sn particles

    Energy Technology Data Exchange (ETDEWEB)

    Alexandrescu, R., E-mail: ralexandrescu2001@yahoo.co.uk [National Institute for Lasers, Plasma and Radiation Physics Bucharest, POB MG-36, 077125 (Romania); Morjan, I.; Dumitrache, F.; Birjega, R.; Fleaca, C.; Morjan, Iuliana; Scarisoreanu, M.; Luculescu, C.R.; Dutu, E. [National Institute for Lasers, Plasma and Radiation Physics Bucharest, POB MG-36, 077125 (Romania); Kuncser, V.; Filoti, G. [National Institute of Materials Physics, POB MG-7, 077125 Bucharest-Magurele (Romania); Vasile, E. [Metav R and D, Rosetti 31, Bucharest (Romania); Ciupina, V. [Ovidius University of Constanta, Bd. Mamaia 124, Constanta (Romania)

    2012-09-15

    Highlights: Black-Right-Pointing-Pointer Intermetallic Fe-Sn and metallic Sn nanoparticles synthesized by laser pyrolysis. Black-Right-Pointing-Pointer Fe(CO){sub 5} and Sn(CH{sub 3}){sub 4} were used as precursors. Black-Right-Pointing-Pointer FeSn{sub 2}, Sn and Fe{sub 3}SnC phases were identified by XRD. Black-Right-Pointing-Pointer Complex core-shell structural characteristics were found by HRTEM analysis. Black-Right-Pointing-Pointer Higher magnetization was found in samples with increased Fe/Sn atomic ratio. - Abstract: Intermetallic Fe-Sn and nanocrystalline metallic Sn nanoparticles have been successfully synthesized from organic precursors using the laser pyrolysis technique with ethylene as sensitizer. Nano-structured Sn (single phase) was prepared by the pyrolysis of Sn(CH{sub 3}){sub 4} (TMT) vapors. Controlled Fe/Sn atomic ratios, ranging from 0.69 to 1.64 were obtained for the prepared Fe-Sn nanopowders by the control of Fe(CO){sub 5} and TMT flows, respectively. XRD studies evidence three main phases: the tetragonal metallic Sn phase and the intermetallic FeSn{sub 2} phase and, to a much lesser extent, the cubic ternary carbide Fe{sub 3}SnC. Complex core-shell structural characteristics were found by HRTEM analysis. More complete information about the Fe phase distributions in the new intermetallic Fe-Sn nanomaterial is provided by temperature dependent {sup 57}Fe Moessbauer spectroscopy.

  1. Beta decay and isomer spectroscopy in the 132Sn region: New results from EURICA

    Science.gov (United States)

    Jungclaus, A.; Taprogge, J.; Simpson, G. S.; Gey, G.; Nishimura, S.; Doornenbal, P.; Lorusso, G.; Söderström, P.-A.; Sumikama, T.; Xu, Z.; Baba, H.; Browne, F.; Fukuda, N.; Inabe, N.; Isobe, T.; Jung, H. S.; Kameda, D.; Kim, G. D.; Kim, Y.-K.; Kojouharov, I.; Kubo, T.; Kurz, N.; Kwon, Y. K.; Li, Z.; Sakurai, H.; Schaffner, H.; Suzuki, H.; Takeda, H.; Vajta, Z.; Watanabe, H.; Wu, J.; Yagi, A.; Yoshinaga, K.; Bönig, S.; Daugas, J.-M.; Drouet, F.; Gernhäuser, R.; Ilieva, S.; Kröll, T.; Montaner-Pizá, A.; Moschner, K.; Mücher, D.; Nishibata, H.; Orlandi, R.; Steiger, K.; Wendt, A.

    2014-09-01

    The first EURICA campaign with high intensity Uranium beams took place at RIKEN in November/December 2012. Within this campaign experiment NP1112-RIBF85 was performed dedicated to the study of the isomeric and beta decays of neutron-rich Cd, In, Sn and Sb isotopes towards and beyond the N=82 neutron shell closure. In this contribution we will first provide information about the status of the analysis of the extensive data set obtained in this experiment and close with a short outlook.

  2. In As{sub 1–x}Sb{sub x} heteroepitaxial structures on compositionally graded GaInSb and AlGaInSb buffer layers

    Energy Technology Data Exchange (ETDEWEB)

    Guseynov, R. R.; Tanriverdiyev, V. A. [National Academy of Sciences of Azerbaijan, Institute of Physics (Azerbaijan); Kipshidze, G., E-mail: gela.kishidze@stonybrook.ede [Stony Brook, Stony Brook University (United States); Aliyeva, Ye. N.; Aliguliyeva, Kh. V.; Abdullayev, N. A., E-mail: abnadir@mail.ru; Mamedov, N. T. [National Academy of Sciences of Azerbaijan, Institute of Physics (Azerbaijan)

    2017-04-15

    Unrelaxed InAs{sub 1–x}Sb{sub x} (x = 0.43 and 0.38) alloy layers are produced by molecular-beam epitaxy on compositionally graded GaInSb and AlGaInSb buffer layers. The high quality of the thin films produced is confirmed by the results of high-resolution X-ray diffraction analysis and micro-Raman studies. The twomode type of transformation of the phonon spectra of InAs{sub 1–x}Sb{sub x} alloys is established.

  3. Effect of InSb/In0.9Al0.1Sb superlattice buffer layer on the structural and electronic properties of InSb films

    Science.gov (United States)

    Zhao, Xiaomeng; Zhang, Yang; Guan, Min; Cui, Lijie; Wang, Baoqiang; Zhu, Zhanping; Zeng, Yiping

    2017-07-01

    The effect of InSb/In0.9Al0.1Sb buffer layers on InSb thin films grown on GaAs (0 0 1) substrate by molecular beam epitaxy (MBE) is investigated. The crystal quality and the surface morphology of InSb are characterized by XRD and AFM. The carrier transport property is researched through variable temperature hall test. The sharp interface between InSb/In0.9Al0.1Sb is demonstrated important for the high quality InSb thin film. We try different superlattice buffer layers by changing ratios, 2-0.5, thickness, 300-450 nm, and periods, 20-50. According to the function of the dislocation density to the absolute temperature below 150 K with different periods of SL buffers, we can find that the number of periods of superlattice is a major factor to decrease the density of threading dislocations. With the 50 periods SL buffer layer, the electron mobility of InSb at the room temperature and liquid nitrogen cooling temperature is ∼63,000 and ∼4600 cm2/V s, respectively. We deduce that the interface in the SL structure works as a filter layer to prevent the dislocation propagating to the upper InSb thin films.

  4. Physico-chemical properties of Sb-rich (Sb, In)–Te thin films

    Energy Technology Data Exchange (ETDEWEB)

    Hromádko, L., E-mail: Ludek.Hromadko@upce.cz [Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, Pardubice 532 10 (Czech Republic); Přikryl, J.; Střižík, L. [Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, Pardubice 532 10 (Czech Republic); Košt’ál, P. [Department of Inorganic Technology, Faculty of Chemical Technology, University of Pardubice, Doubravice 41, Pardubice 532 10 (Czech Republic); Beneš, L. [Joint Laboratory of Solid State Chemistry of Institute of Macromolecular Chemistry of the Academy of Sciences of the Czech Republic and University of Pardubice, Faculty of Chemical Technology, Studentská 95, Pardubice 532 10 (Czech Republic); Frumar, M. [Department of General and Inorganic Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, Pardubice 532 10 (Czech Republic)

    2014-12-25

    Highlights: • The difference of electrical sheet resistance between amorphous and crystalline state is more than 3 orders. • The crystallization temperature T{sub c} of the prepared films increases with increasing content of indium. • The activation energy of crystallization E{sub a} increased with increasing content of indium. • The prepared thin films could be applied for electrical non-volatile phase change memories. - Abstract: The phase change materials of the system Sb{sub 70−x}In{sub x}Te{sub 30} (x = 0, 7 and 14) were studied. The thin films prepared by thermal flash evaporation were amorphous with high electrical sheet resistance (R{sub s}) (≈10{sup 6} Ω/sqr., T = 300 K). When heated, the resistance dropped to 10–10{sup 2} Ω/sqr. due to crystallization of the films. The crystallization temperatures were 113, 158 and 183 °C for Sb{sub 70}Te{sub 30}, Sb{sub 63}In{sub 7}Te{sub 30} and Sb{sub 56}In{sub 14}Te{sub 30}, respectively. The activation energies of crystallization as evaluated by Kissinger’s plot were 2.42, 2.72 and 3.15 eV for Sb{sub 70}Te{sub 30}, Sb{sub 63}In{sub 7}Te{sub 30} and Sb{sub 56}In{sub 14}Te{sub 30}, respectively. The optical band gap of amorphous films increases with increasing content of indium from 0.38 to 0.47 eV. Values of refractive index were found in range of 5.43–4.77 (λ = 1500 nm) for amorphous state and 7.06–5.89 for crystalline state in dependence on composition. They decreased with increasing content of indium.

  5. Transport Measurements on Si Nanostructures with Counted Sb Donors

    Science.gov (United States)

    Singh, Meenakshi; Bielejec, Edward; Garratt, Elias; Ten Eyck, Gregory; Bishop, Nathaniel; Wendt, Joel; Luhman, Dwight; Carroll, Malcolm; Lilly, Michael

    2014-03-01

    Donor based spin qubits are a promising platform for quantum computing. Single qubits using timed implant of donors have been demonstrated.1 Extending this to multiple qubits requires precise control over the placement and number of donors. Such control can be achieved by using a combination of low-energy heavy-ion implants (to reduce depth straggle), electron-beam lithography (to define position), focused ion beam (to localize implants to one lithographic site) and counting the number of implants with a single ion detector.2 We report transport measurements on MOS quantum dots implanted with 5, 10 and 20 Sb donors using the approach described above. A donor charge transition is identified by a charge offset in the transport characteristics. Correlation between the number of donors and the charge offsets is studied. These results are necessary first steps towards fabricating donor nanostructures for two qubit interactions. This work was performed, in part, at the Center for Integrated Nanotechnologies, a U.S. DOE Office of Basic Energy Sciences user facility. The work was supported by Sandia National Laboratories Directed Research and Development Program. Sandia National Laboratories is a multi-program laboratory operated by Sandia Corporation, a Lockheed-Martin Company, for the U. S. Department of Energy under Contract No. DE-AC04-94AL85000. 1J. J. Pla et al., Nature 496, 334 (2013) 2J. A. Seamons et al., APL 93, 043124 (2008).

  6. La5Zn2Sn

    Directory of Open Access Journals (Sweden)

    Igor Oshchapovsky

    2011-11-01

    Full Text Available A single crystal of pentalanthanum dizinc stannide, La5Zn2Sn, was obtained from the elements in a resistance furnace. It belongs to the Mo5SiB2 structure type, which is a ternary ordered variant of the Cr5B3 structure type. The space is filled by bicapped tetragonal antiprisms from lanthanum atoms around tin atoms sharing their vertices. Zinc atoms fill voids between these bicapped tetragonal antiprisms. All four atoms in the asymmetric unit reside on special positions with the following site symmetries: La1 (..m; La2 (4/m..; Zn (m.2m; Sn (422.

  7. Wear properties of hybrid ABO+BN+CNT/Al-Sn alloy matrix composites for engine bearing materials

    Science.gov (United States)

    Bak, Ji Hyeon; Cho, Dae Hyun; Shin, Sunmi; Park, Jin Young; Park, Ik Min

    2018-01-01

    Engine bearing materials need improved wear resistance to withstand high speeds and heavy loads. To meet the requirements of bearing materials, a new metal matrix composite (MMC) was designed. Here, the hybrid aluminum borate whisker (Al18B4O33, ABO) + hexagonal boron nitride (BN) + carbon nanotubes (CNTs)/Al-5Sn alloy MMCs were fabricated by squeeze infiltration. The wear properties of the hybrid MMCs were evaluated using a ball-on-disk tester. The effect of hybridization of ABO, BN, and CNTs on the wear properties of the Al-Sn MMCs was investigated. The microstructure of the hybrid MMCs showed a uniform distribution of the reinforcements. The wear resistance of the Al-5Sn alloy improved with the addition of ABO. The wear properties of the ABO+BN/ Al-Sn and ABO+CNT/Al-Sn MMCs were considerably enhanced compared to those of the ABO reinforced Al-Sn MMC because of the lubricating characteristic of BN and CNTs, and the CNTs were more effective than BN. The friction coefficient and wear rate of 20ABO+5BN+5CNT/Al-Sn MMC decreased by 1/4 and 1/20, respectively, compared to that of the ABO/Al-Sn MMC.

  8. Nearly massless Dirac fermions hosted by Sb square net in BaMnSb2.

    Science.gov (United States)

    Liu, Jinyu; Hu, Jin; Cao, Huibo; Zhu, Yanglin; Chuang, Alyssa; Graf, D; Adams, D J; Radmanesh, S M A; Spinu, L; Chiorescu, I; Mao, Zhiqiang

    2016-07-28

    Layered compounds AMnBi2 (A = Ca, Sr, Ba, or rare earth element) have been established as Dirac materials. Dirac electrons generated by the two-dimensional (2D) Bi square net in these materials are normally massive due to the presence of a spin-orbital coupling (SOC) induced gap at Dirac nodes. Here we report that the Sb square net in an isostructural compound BaMnSb2 can host nearly massless Dirac fermions. We observed strong Shubnikov-de Haas (SdH) oscillations in this material. From the analyses of the SdH oscillations, we find key signatures of Dirac fermions, including light effective mass (~0.052m0; m0, mass of free electron), high quantum mobility (1280 cm(2)V(-1)S(-1)) and a π Berry phase accumulated along cyclotron orbit. Compared with AMnBi2, BaMnSb2 also exhibits much more significant quasi two-dimensional (2D) electronic structure, with the out-of-plane transport showing nonmetallic conduction below 120 K and the ratio of the out-of-plane and in-plane resistivity reaching ~670. Additionally, BaMnSb2 also exhibits a G-type antiferromagnetic order below 283 K. The combination of nearly massless Dirac fermions on quasi-2D planes with a magnetic order makes BaMnSb2 an intriguing platform for seeking novel exotic phenomena of massless Dirac electrons.

  9. SN 2009E: a faint clone of SN 1987A

    DEFF Research Database (Denmark)

    Pastorello, A.; Pumo, M. L.; Navasardyan, H.

    2012-01-01

    Context.1987A-like events form a rare sub-group of hydrogen-rich core-collapse supernovae that are thought to originate from the explosion of blue supergiant stars. Although SN 1987A is the best known supernova, very few objects of this group have been discovered and, hence, studied. Aims. In thi...

  10. Transition probabilities for lines of Cr II, Na II and Sb I by laser produced plasma atomic emission spectroscopy; Probabilidades de transicion de algunos niveles de Cr II, Na II y Sb I medediante espectroscopia de plasma producidos por laser

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, A. M.; Ortiz, M.; Campos, J.

    1995-07-01

    Absolute transition probabilities for lines of CR II, Na II and Sb I were determined by emission spectroscopy of laser induced plasmas. the plasma was produced focusing the emission of a pulsed Nd-Yag laser on solid samples containing the atom in study. the light arising from the plasma region was collected by and spectrometer. the detector used was a time-resolved optical multichannel analyzer (OMA III EG and G). The wavelengths of the measured transitions range from 2000 sto 4100 A. The spectral resolution of the system was 0. 2 A. The method can be used in insulators materials as Cl Na crystals and in metallic samples as Al-Cr and Sn-Sn alloys. to avoid self-absorption effects the alloys were made with low Sb or Cr content. Relative transition probabilities have been determined from measurements of emission-line intensities and were placed on an absolute scale by using, where possible, accurate experimental lifetime values form the literature or theoretical data. From these measurements, values for plasma temperature (8000-24000 K), electron densities ({approx}{approx} 10''16 cm ''-3) and self-absorption coefficients have been obtained. (Author) 56 refs.

  11. Microbiological reduction of Sb(V) in anoxic freshwater sediments

    Science.gov (United States)

    Oremland, Ronald S.; Kulp, Thomas R.; Miller, Laurence G.; Braiotta, Franco; Webb, Samuel M.; Kocar, Benjamin D; Blum, Jodi S.

    2014-01-01

    Microbiological reduction of millimolar concentrations of Sb(V) to Sb(III) was observed in anoxic sediments from two freshwater settings: (1) a Sb- and As-contaminated mine site (Stibnite Mine) in central Idaho and 2) an uncontaminated suburban lake (Searsville Lake) in the San Francisco Bay Area. Rates of Sb(V) reduction in anoxic sediment microcosms and enrichment cultures were enhanced by amendment with lactate or acetate as electron donors but not by H2, and no reduction occurred in sterilized controls. Addition of 2-14C-acetate to Stibnite Mine microcosms resulted in the production of 14CO2 coupled to Sb(V) reduction, suggesting that this process proceeds by a dissimilatory respiratory pathway in those sediments. Antimony(V) reduction in Searsville Lake sediments was not coupled to acetate mineralization and may be associated with Sb-resistance. The microcosms and enrichment cultures also reduced sulfate, and the precipitation of insoluble Sb(III)-sulfide complexes was a major sink for reduced Sb. The reduction of Sb(V) by Stibnite Mine sediments was inhibited by As(V), suggesting that As(V) is a preferred electron acceptor for the indigenous community. These findings indicate a novel pathway for anaerobic microbiological respiration and suggest that communities capable of reducing high concentrations of Sb(V) commonly occur naturally in the environment.

  12. Laser processing issues of nanosized intermetallic Fe-Sn and metallic Sn particles

    Science.gov (United States)

    Alexandrescu, R.; Morjan, I.; Dumitrache, F.; Birjega, R.; Fleaca, C.; Morjan, Iuliana; Scarisoreanu, M.; Luculescu, C. R.; Dutu, E.; Kuncser, V.; Filoti, G.; Vasile, E.; Ciupina, V.

    2012-09-01

    Intermetallic Fe-Sn and nanocrystalline metallic Sn nanoparticles have been successfully synthesized from organic precursors using the laser pyrolysis technique with ethylene as sensitizer. Nano-structured Sn (single phase) was prepared by the pyrolysis of Sn(CH3)4 (TMT) vapors. Controlled Fe/Sn atomic ratios, ranging from 0.69 to 1.64 were obtained for the prepared Fe-Sn nanopowders by the control of Fe(CO)5 and TMT flows, respectively. XRD studies evidence three main phases: the tetragonal metallic Sn phase and the intermetallic FeSn2 phase and, to a much lesser extent, the cubic ternary carbide Fe3SnC. Complex core-shell structural characteristics were found by HRTEM analysis. More complete information about the Fe phase distributions in the new intermetallic Fe-Sn nanomaterial is provided by temperature dependent 57Fe Mössbauer spectroscopy.

  13. Cs-137 geochronology, epithermal neutron activation analysis, and principal component analysis of heavy metals pollution of the Black Sea anoxic continental shelf sediments

    Science.gov (United States)

    Duliu, O. G.; Cristache, C.; Oaie, G.; Culicov, O. A.; Frontasyeva, M. V.

    2009-04-01

    concentrations; k represents the surface to plateau relative increment of concentration; Z represents concentration decrement: the depth at which the concentration becomes 1+k times greater than plateau one. Final results have shown with clarity that in the case of Zn, As, Br, Sn and Sb, the concentrations near sediment surface were 1.6 to 4.1 times greater then the plateau ones while Sc vertical profile, excepting some small fluctuations observed between 18 to 25 cm below surface, shown to be almost constant. Moreover, the concentration decrements Z of Zn, Br, Sn and Sb were almost coincident within one standard deviation while in the case of As, this coincidence appears within two standard deviation, these facts pleading for a comparable time evolution in the past 100 years. On the other hand, in the case of Sn and As, the maximum concentrations were reached 1 cm below the sediment surface, roughly corresponding to 1990 year, while the concentrations of all other three elements monotonously increases up to sediment surface. Further Principal Components Analysis of the data concerning the vertical distribution of all six elements illustrates the presence of two distinct clusters, one consisting of Zn, As, Br, Sn and Sb and the other on only of Sn, attesting both differences and similarities in the vertical distribution of considered elements. By comparing the experimental concentrations of all five elements with Romania Regulations concerning heavy metal pollution, we remarked that, by respect to these Regulations the only Zn, As, Br and Sb slightly exceeded normal accepted limits while the minimum alert concentrations were exceeded only in few cases by of As and Br, but no elements concentrations reached the intervention threshold. In our opinion, these results reflect the dynamics of the industrial activity in the riparian to Danube River European countries: a steady increase beginning with the last half of the XIX-th century followed by a slightly decline after the fall of

  14. Optical and structural properties of MOVPE-grown GaInSb/GaSb quantum wells

    Energy Technology Data Exchange (ETDEWEB)

    Wagener, Viera, E-mail: viera.wagener@nmmu.ac.z [Physics Department, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031 (South Africa); Olivier, E.J.; Botha, J.R. [Physics Department, Nelson Mandela Metropolitan University, PO Box 77000, Port Elizabeth 6031 (South Africa)

    2009-12-15

    This paper reports on the optical and structural properties of strained type-I Ga{sub 1-x}In{sub x}Sb quantum wells embedded in GaSb from a metal-organic vapour phase epitaxial growth perspective. Photoluminescence measurements and transmission electron microscopy were used to evaluate the effect of the growth temperature on the quality of Ga{sub 1-x}In{sub x}Sb strained layers with varied alloy compositions and thicknesses. Although the various factors contributing to the overall quality of the strained layers are difficult to separate, the quantum well characteristics are significantly altered by the growth temperature. Despite the high growth rates (approx2 nm/s), quantum wells grown at 607 deg. C display photoluminescence emissions with full-width at half-maximum of 3.5-5.0 meV for an indium solid content (x) up to 0.15.

  15. Optical Characterization of AlAsSb Digital Alloy and Random Alloy on GaSb

    Directory of Open Access Journals (Sweden)

    Bor-Chau Juang

    2017-10-01

    Full Text Available III-(As, Sb alloys are building blocks for various advanced optoelectronic devices, but the growth of their ternary or quaternary materials are commonly limited by spontaneous formation of clusters and phase separations during alloying. Recently, digital alloy growth by molecular beam epitaxy has been widely adopted in preference to conventional random alloy growth because of the extra degree of control offered by the ordered alloying. In this article, we provide a comparative study of the optical characteristics of AlAsSb alloys grown lattice-matched to GaSb using both techniques. The sample grown by digital alloy technique showed stronger photoluminescence intensity, narrower peak linewidth, and larger carrier activation energy than the random alloy technique, indicating an improved optical quality with lower density of non-radiative recombination centers. In addition, a relatively long carrier lifetime was observed from the digital alloy sample, consistent with the results obtained from the photoluminescence study.

  16. Study of dual color infrared photodetection from n-GaSb/n-InAsSb heterostructures

    Directory of Open Access Journals (Sweden)

    Jinchao Tong

    2016-02-01

    Full Text Available We report detailed investigation of n-GaSb/n-InAsSb heterostructure photodetectors for infrared photodetection at different temperatures and biases. Our results show that the heterostructure photodetectors are capable of dual color photodetections at a fixed forward bias with its highest responsivity occurred at room temperature; With the decrease of the forward bias, a turning point, at which the photocurrent changes its direction, exist and the corresponding voltage values increases with the decrease of temperature; At all reverse biases, the photocurrents flow in the same direction but the maximum current occurs at about 205 K. A new model is proposed, which can well explain all the observations.

  17. Decay of the $r$-process nuclides $^{137, 138, 139}$Sb, and the A=130 solar $r$-process abundance peak

    CERN Document Server

    Arndt, O; Farouqi, K; Koester, U; Kratz, K-L; Pfeiffer, B; Walters, W B; Hoteling, N; Fedosseev, V; Hennrich, S; Woehr, A; Shergur, J; Hecht, A A

    2011-01-01

    Half-life (T(1/2)) and beta-delayed neutron branching (P(n)) values of 492(25) ms and 49(8)\\%, 350(15) ms and 72(8)\\%, and 93(13) ms and 90(10)\\% for the r-process nuclei (137,138,139)Sb, respectively, have been measured at the CERN On-Line Isotope Mass Separator (ISOLDE) facility by counting beta-delayed neutrons. More precise T(1/2) and P(n) values of 300(15) ms and 27(4)\\%, and 273(7) ms and 50(8)\\% for (136,137)Sn, respectively, have also been measured. The sources were prepared by using the selective ionization of Sb or Sn with the Resonance Ionization Laser Ion Source and the high-resolution mass separator. The new data for Sb isotopes are compared with calculated T(1/2) and P(n) values for both spherical and nonspherical shapes. The data have been incorporated into parametrized nucleosynthesis calculations of the r process in high-entropy winds of core-collapse supernovae in order to study the properties of the A = 130 solar-system r-process abundance peak.

  18. Heavy flavour in ALICE

    CERN Document Server

    Pillot, Philippe

    2008-01-01

    Open heavy flavours and heavy quarkonium states are expected to provide essential informa- tion on the properties of the strongly interacting system fo rmed in the early stages of heavy-ion collisions at very high energy density. Such probes are espe cially promising at LHC energies where heavy quarks (both c and b) are copiously produced. The ALICE detector shall measure the production of open heavy flavours and heavy quarkonium st ates in both proton-proton and heavy-ion collisions at the LHC. The expected performances of ALICE for heavy flavour physics is discussed based on the results of simulation studies on a s election of benchmark channels

  19. Crystal structure of Ba5In4Sb6

    Directory of Open Access Journals (Sweden)

    Ming-Yan Pan

    2015-05-01

    Full Text Available The title compound, pentabarium tetraindium hexaantimony, was synthesized by an indium-flux reaction and its structure features layers composed of edge-sharing In2Sb6 units. The voids between the In4Sb6 layers are filled by Ba2+ cations, which are all surrounded by six Sb atoms and form bicapped octahedral or triangular prismatic coordination geometries. There are five barium ions in the asymmetric unit: one has no imposed crystallographic symmetry, two lie on mirror planes and two have mm2 point symmetry. The two In atoms and four Sb atoms in the asymmetric unit all lie on general crystallographic positions.

  20. Synthesis of B–Sb by rapid thermal annealing of B/Sb multilayer films

    Indian Academy of Sciences (India)

    layer with predetermined thickness of boron and antimony and subsequently subjecting the multilayer to rapid thermal annealing. The films were characterized by measuring microstructural, optical and compositional properties. 2. Experimental. Multilayer films of B and Sb were deposited onto Si and fused silica substrates ...

  1. Strained InGaSb/AlGa(As)Sb Quantum Wells for p-Channel Transistors

    Science.gov (United States)

    Bennett, Brian R.; Podpirka, Adrian A.; Boos, J. B.; Kumar, Satvika L.

    2016-06-01

    Quantum wells of InGaSb clad by AlGa(As)Sb were grown by molecular beam epitaxy. Well and barrier compositions were chosen to yield biaxial compressive strain and enhanced hole mobility in the InGaSb. Wells with thickness of 7.5 nm exhibited room-temperature mobilities of 1000 cm2/V s to 1100 cm2/V s, with the surface-layer material influencing two-dimensional hole densities. The introduction of As into the barrier material allows a wider range of p-channel well/barrier combinations and lattice constants. These could be compatible with n-channel InGaAs wells for complementary field-effect transistor circuits which utilize a common buffer layer. InGaSb wells with thicknesses of 20 nm to 30 nm and compressive strains of 1.0% to 1.5% exhibited hole mobilities of 700 cm2/V s to 900 cm2/V s.

  2. Strong fragmentation of low-energy electromagnetic excitation strength in $^{117}Sn$

    CERN Document Server

    Ponomarev, V Yu; Govor, L; Bauwens, F; Beck, O; Belic, D; Von Brentano, P; De Frenne, D; Fransen, C; Herzberg, R D; Jacobs, E; Kneissl, U; Maser, H; Nord, A; Pietralla, N; Pitz, H H; Werner, V

    1999-01-01

    Results of nuclear resonance fluorescence experiments on $^{117}$Sn are reported. More than 50 $\\gamma$ transitions with $E_{\\gamma} < 4$ MeV were detected indicating a strong fragmentation of the electromagnetic excitation strength. For the first time microscopic calculations making use of a complete configuration space for low-lying states are performed in heavy odd-mass spherical nuclei. The theoretical predictions are in good agreement with the data. It is concluded that although the E1 transitions are the strongest ones also M1 and E2 decays contribute substantially to the observed spectra. In contrast to the neighboring even $^{116-124}$Sn, in $^{117}$Sn the $1^-$ component of the two-phonon $[2^+_1 \\otimes 3^-_1]$ quintuplet built on top of the 1/2$^+$ ground state is proved to be strongly fragmented.

  3. Improved structural and electrical properties in native Sb2Te3/GexSb2Te3+x van der Waals superlattices due to intermixing mitigation

    NARCIS (Netherlands)

    Cecchi, Stefano; Zallo, Eugenio; Momand, Jamo; Wang, Ruining; Kooi, Bart J.; Verheijen, Marcel A.; Calarco, Raffaella

    Superlattices made of Sb2Te3/GeTe phase change materials have demonstrated outstanding performance with respect to GeSbTe alloys in memory applications. Recently, epitaxial Sb2Te3/GeTe superlattices were found to feature GexSb2Te3+x blocks as a result of intermixing between constituting layers.

  4. Catalytic growth of vertically aligned SnS/SnS2 p-n heterojunctions

    Science.gov (United States)

    Degrauw, Aaron; Armstrong, Rebekka; Rahman, Ajara A.; Ogle, Jonathan; Whittaker-Brooks, Luisa

    2017-09-01

    Nanowire arrays of SnS/SnS2 p-n heterojunctions are grown on transparent indium tin oxide (ITO) coated-glass and Si/SiO2 substrates via chemical vapor transport (CVT). The nanowire arrays are comprised of individual SnS/SnS2 heterostructures that are highly oriented with their lengths and morphologies controlled by the CVT conditions (i.e. reaction temperature, flow rate, and reaction time). The growth and optoelectronic characterization of these well-defined SnS/SnS2 p-n heterostructures pave the way for the fabrication of highly efficient solar cell devices.

  5. Features of high-temperature electroluminescence in an LED n-GaSb/n-InGaAsSb/p-AlGaAsSb heterostructure with high potential barriers

    Energy Technology Data Exchange (ETDEWEB)

    Danilov, L. V., E-mail: danleon84@mail.ru; Petukhov, A. A.; Mikhailova, M. P.; Zegrya, G. G.; Ivanov, E. V.; Yakovlev, Yu. P. [Russian Academy of Sciences, Ioffe Physical–Technical Institute (Russian Federation)

    2016-06-15

    The electroluminescent properties of a light-emitting diode n-GaSb/n-InGaAsSb/p-AlGaAsSb heterostructure with high potential barriers are studied in the temperature range of 290–470 K. An atypical temperature increase in the power of the long-wavelength luminescence band with an energy of 0.3 eV is experimentally observed. As the temperature increases to 470 K, the optical radiation power increases by a factor of 1.5–2. To explain the extraordinary temperature dependence of the radiation power, the recombination and carrier transport processes are theoretically analyzed in the heterostructure under study.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-08-10

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

  7. Superconductivity of the filled skuterrudite PrOs{sub 4}Sb{sub 12}: Phase diagram and characterisations

    Energy Technology Data Exchange (ETDEWEB)

    Measson, M.-A. [Departement de Recherche Fondamentale sur la Matiere Condensee, SPSMS, CEA Grenoble, 38054 Grenoble (France)]. E-mail: mmeasson@cea.fr; Brison, J.P. [Centre de Recherches sur les Tres Basses Temperatures, CNRS, 25 avenue des Martyrs, BP166, 38042 Grenoble Cedex (France)]. E-mail: brison@grenoble.cnrs.fr; Seyfarth, G. [Centre de Recherches sur les Tres Basses Temperatures, CNRS, 25 avenue des Martyrs, BP166, 38042 Grenoble Cedex (France); Braithwaite, D. [Departement de Recherche Fondamentale sur la Matiere Condensee, SPSMS, CEA Grenoble, 38054 Grenoble (France); Lapertot, G. [Departement de Recherche Fondamentale sur la Matiere Condensee, SPSMS, CEA Grenoble, 38054 Grenoble (France); Salce, B. [Departement de Recherche Fondamentale sur la Matiere Condensee, SPSMS, CEA Grenoble, 38054 Grenoble (France); Flouquet, J. [Departement de Recherche Fondamentale sur la Matiere Condensee, SPSMS, CEA Grenoble, 38054 Grenoble (France); Lhotel, E. [Centre de Recherches sur les Tres Basses Temperatures, CNRS, 25 avenue des Martyrs, BP166, 38042 Grenoble Cedex (France); Paulsen, C. [Centre de Recherches sur les Tres Basses Temperatures, CNRS, 25 avenue des Martyrs, BP166, 38042 Grenoble Cedex (France); Sugawara, H. [Department of Physics, Tokyo Metropolitan University, Minami-Ohsawa 1-1, Hashioji, Tokyo 192-0397 (Japan); Sato, H. [Department of Physics, Tokyo Metropolitan University, Minami-Ohsawa 1-1, Hashioji, Tokyo 192-0397 (Japan); Canfield, P.C. [Ames Laboratory Department of Physics and Astronomy, Iowa State University, Ames, IA 50011 (United States); Izawa, K. [Institute for Solid State Physics, University of Tokyo, Kashiwanoha 5-1-5 Kashiwa, Chiba 277-8581 (Japan); Matsuda, Y. [Institute for Solid State Physics, University of Tokyo, Kashiwanoha 5-1-5 Kashiwa, Chiba 277-8581 (Japan)

    2005-04-30

    We present a precise (H-T) phase diagram of the double superconducting transition in the specific heat of the heavy fermion superconductor PrOs{sub 4}Sb{sub 12}, down to 350mK, on a sample which exhibits two sharp distinct anomalies at T{sub c1}=1.89K and T{sub c2}=1.72K. Comparison with an existing phase diagram based on transport measurements will be reviewed. The intrinsic or extrinsic nature of this double transition is discussed in light of some characterisations of the superconducting transition of different samples and with respect to the historical case of UPt{sub 3}. Finally, we give a detailed analysis of H{sub c2} which shows the importance of the multiband character of the electronic structure of PrOs{sub 4}Sb{sub 12} and gives strong support to an even parity order parameter.

  8. Recent development of SWIR focal plane array with InGaAs/GaAsSb type-II quantum wells

    Science.gov (United States)

    Inada, Hiroshi; Machinaga, Kenichi; Balasekaran, Sundararajan; Miura, Kouhei; Kawahara, Takahiko; Migita, Masaki; Akita, Katsushi; Iguchi, Yasuhiro

    2016-05-01

    HgCdTe (MCT) is predominantly used for infrared imaging applications even in SWIR region. However, MCT is expensive and contains environmentally hazardous substances. Therefore, its application has been restricted mainly military and scientific use and was not spread to commercial use. InGaAs/GaAsSb type-II quantum well structures are considered as an attractive material for realizing low dark current PDs owing to lattice-matching to InP substrate. Moreover, III-V compound material systems are suitable for commercial use. In this report, we describe successful operation of focal plane array (FPA) with InGaAs/GaAsSb quantum wells and mention improvement of optical characteristics. Planar type pin-PDs with 250-pairs InGaAs(5nm)/GaAsSb(5nm) quantum well absorption layer were fabricated. The p-n junction was formed in the absorption layer by the selective diffusion of zinc. Electrical and optical characteristics of FPA or pin-PDs were investigated. Dark current of 1μA/cm2 at 210K, which showed good uniformity and led to good S/N ratio in SWIR region, was obtained. Further, we could successfully reduce of stray light in the cavity of FPA with epoxy resin. As a result, the clear image was taken with 320x256 format and 7% contrast improvement was achieved. Reliability test of 10,000 heat cycles was carried out. No degradations were found in FPA characteristics of the epoxy coated sample. This result means FPA using InGaAs/GaAsSb type-II quantum wells is a promising candidate for commercial applications.

  9. Controlling the antibacterial activity of CuSn thin films by varying the contents of Sn

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Yujin; Park, Juyun; Kim, Dong-Woo; Kim, Hakjun; Kang, Yong-Cheol, E-mail: yckang@pknu.ac.kr

    2016-12-15

    Highlights: • We deposit CuSn thin films on a Si substrate with various Cu/Sn ratio. • Antibacterial activities of CuSn thin films increased as the ratio of Cu and the contact time increased. • XPS was utilized to assign the chemical environment of CuSn thin films before and after antibacterial test. - Abstract: We investigated antibacterial activity of CuSn thin films against Gram positive Staphylococcus aureus (S. aureus). CuSn thin films with different Cu to Sn ratios were deposited on Si(100) by radio frequency (RF) magnetron sputtering method using Cu and Sn metal anodes. The film thickness was fixed at 200 nm by varying the sputtering time and RF power on the metal targets. The antibacterial test was conducted in various conditions such as different contact times and Cu to Sn ratios in the CuSn films. The antibacterial activities of CuSn thin films increased as the ratio of Cu and the contact time between the film and bacteria suspension increased execpt in the case of CuSn-83. The oxidation states of Cu and Sn and the chemical composition of CuSn thin films before and after the antibacterial test were investigated by X-ray photoelectron spectroscopy (XPS). When the contact time was fixed, the Cu species was further oxidized as the RF power on Cu target increased. The intensity of Sn 3d decreased with increasing Cu ratio. When the sample was fixed, the peak intensity of Sn 3d decreased as the contact time increased due to the permeation of Sn into the cell.

  10. Mid-IR InAsSb photovoltaic detectors

    Science.gov (United States)

    Rakovska, Anna; Berger, Vincent; Marcadet, Xavier; Glastre, Genevieve; Vinter, Borge; Bouzehouane, K.; Kaplan, Daniel; Oksehendler, T.

    2000-04-01

    We describe a mid-IR photovoltaic detector using InAsSb as active material, grown by MBE on a GaSb substrate. The purpose of this study is to show that quantum detectors can offer an alternative to thermal detectors for high temperature operation. With a 9 percent Sb content, InAsSb is lattice matched to GaSb and thus provides an excellent material quality, with Shokley-Read lifetimes of the order of 200 ns as measured by photoconductive gain measurements as well as time resolved photoconductivity experiments. The band gap of InAsSb corresponds to a wavelengths as well as time resolved photoconductivity experiments. The band gap of InAsSb corresponds to a wavelength of 5 microns at room temperature. This makes InAsSb an ideal candidate for rom temperature detection in the 3-5 microns atmospheric window. Photovoltaic structures are characterized by current voltage characteristics as a function of temperature. Using the absorption value obtained on the test samples, a detectivity of 7 by 109 Jones can be obtained at a temperature of 250 K, which can easily be reached with Peltier cooling. This leads to a NETD lower than 80 mK.

  11. Reduction of [Cp*Sb]4 with Subvalent Main-Group Metal Reductants: Syntheses and Structures of [(L1 Mg)4 (Sb4 )] and [(L2 Ga)2 (Sb4 )] Containing Edge-Missing Sb4 Units.

    Science.gov (United States)

    Ganesamoorthy, Chelladurai; Krüger, Julia; Wölper, Christoph; Nizovtsev, Anton S; Schulz, Stephan

    2017-02-16

    [Cp*Sb]4 (Cp*=C5 Me5 ) reacts with [L1 Mg]2 and L2 Ga with formation of [(L1 Mg)4 (μ4 ,η1:2:2:2 -Sb4 )] (L1 =iPr2 NC[N(2,6-iPr2 C6 H3 )]2 , 1) and [(L2 Ga)2 (μ,η2:2 -Sb4 )] (L2 =HC[C(Me)N(2,6-iPr2 C6 H3 )]2 , 2). The cleavage of the Sb-Sb and Sb-C bonds in [Cp*Sb]4 are the crucial steps in both reactions. The formation of 1 occurred by elimination of the Cp* anion and formation of Cp*MgL1 , while 2 was formed by reductive elimination of Cp*2 and oxidative addition of L2 Ga to the Sb4 unit. 1 and 2 were characterized by heteronuclear NMR spectroscopy and single-crystal X-ray diffraction, and their bonding situation was studied by quantum chemical calculations. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. SULFURIC ACID CORROSION OF LOW Sb - Pb BATTERY ALLOYS

    African Journals Online (AJOL)

    user

    1 SEPTEMBER 1983 NTUKOGU. 42. SULFURIC ACID CORROSION OF LOW Sb - Pb BATTERY ALLOYS by. T. O. Ntukogu. Mechanical Engineering Department. University of Nigeria, Nsukka. (Manuscript received February,1983). ABSTRACT. The corrosion properties of low Sb - Pb alloys developed for maintenance free ...

  13. Undoped InSb radiation detector for radiation measurement

    CERN Document Server

    Hishiki, S; Sugiura, O; Murase, Y; Nakamura, T; Katagiri, M

    2003-01-01

    A Schottky type detector was fabricated with undoped InSb wafer. We could measure the energy of sup 2 sup 4 sup 1 Am alpha particles with this InSb detector at the operating temperature from 2 K to 65 K.

  14. Effects of Y, Nd and Sb on microstructure of Mg-6Al alloy

    Science.gov (United States)

    Li, Ke-jie

    2017-09-01

    Effects of Y, Nd and Sb on the microstructure of Mg-6Al magnesium alloy were investigated by optical microscope, SEM, EDS, XRD and TEM. The results showed that, with the increase of Sb content from 0.5% to 2.0wt%, the formation of Sb3Y5 (at 1.0% Sb) or YSb (at 2.0% Sb) phase is observed. Sb3Y5 nano-phase and dispersed Al2Y, SbY phases are found in the alloy when the content of Sb reaches 2.0%.

  15. The crystal structure of ferdowsiite Ag8Sb4(As,Sb)4S16 and its relations to other ABX2 (A=Ag; B=As,Sb,Bi; X=S,Se) structures

    DEFF Research Database (Denmark)

    Makovicky, Emil; Topa, Dan

    2014-01-01

    site has three short Sb-S bonds 2.503–2.645 Å. As and Sb in the mixed site were refined separately, with isotropic displacement coefficients. As has typical bond length values of 2.248–2.354 Å whereas Sb has 2.443–2.392 Å, i.e., the observed ligand positions are visibly influenced by the predominant...... of ferdowsiite, approximately Ag8Sb4(As,Sb)4S16, contains four distinct cation and four different anion sites in the asymmetric unit, all in general positions. Besides two Ag sites and one Sb site, the crystal structure contains one mixed As-Sb coordination polyhedron (0.63 As and 0.37 Sb in the site). The Sb1...

  16. Process modules for GeSn nanoelectronics with high Sn-contents

    Science.gov (United States)

    Schulte-Braucks, C.; Glass, S.; Hofmann, E.; Stange, D.; von den Driesch, N.; Hartmann, J. M.; Ikonic, Z.; Zhao, Q. T.; Buca, D.; Mantl, S.

    2017-02-01

    This paper systematically studies GeSn n-FETs, from individual process modules to a complete device. High-k gate stacks and NiGeSn metallic contacts for source and drain are characterized in independent experiments. To study both direct and indirect bandgap semiconductors, a range of 0-14.5 at.% Sn-content GeSn alloys are investigated. Special emphasis is placed on capacitance-voltage (C-V) characteristics and Schottky-barrier optimization. GeSn n-FET devices are presented including temperature dependent I-V characteristics. Finally, as an important step towards implementing GeSn in tunnel-FETs, negative differential resistance in Ge0.87Sn0.13 tunnel-diodes is demonstrated at cryogenic temperatures. The present work provides a base for further optimization of GeSn FETs and novel tunnel FET devices.

  17. Antimony (Sb) and arsenic (As) in Sb mining impacted paddy soil from Xikuangshan, China: differences in mechanisms controlling soil sequestration and uptake in rice.

    Science.gov (United States)

    Okkenhaug, Gudny; Zhu, Yong-Guan; He, Junwen; Li, Xi; Luo, Lei; Mulder, Jan

    2012-03-20

    Foods produced on soils impacted by antimony (Sb) mining activities are a potential health risk due to plant uptake of the contaminant metalloids (Sb) and arsenic (As). Here we report for the first time the chemical speciation of Sb in soil and porewater of flooded paddy soil, impacted by active Sb mining, and its effect on uptake and speciation in rice plants (Oryza sativa L. cv Jiahua). Results are compared with behavior and uptake of As. Pot experiments were conducted under controlled conditions in a climate chamber over a period of 50 days. In pots without rice plants, flooding increased both the concentration of dissolved Sb (up to ca. 2000 μg L(-1)) and As (up to ca. 1500 μg L(-1)). When rice was present, Fe plaque developing on rice roots acted as a scavenger for both As and Sb, whereby the concentration of As, but not Sb, in porewater decreased substantially. Dissolved Sb in porewater, which occurred mainly as Sb(V), correlated with Ca, indicating a solubility governed by Ca antimonate. No significant differences in bioaccumulation factor and translocation factor between Sb and As were observed. Greater relative concentration of Sb(V) was found in rice shoots compared to rice root and porewater, indicating either a preferred uptake of Sb(V) or possibly an oxidation of Sb(III) to Sb(V) in shoots. Adding soil amendments (olivine, hematite) to the paddy soil had no effect on Sb and As concentrations in porewater.

  18. SN1987A's Twentieth Anniversary

    Science.gov (United States)

    2007-02-01

    Looking back at 20 Years of Observations of this Supernova with ESO telescopes The unique supernova SN 1987A has been a bonanza for astrophysicists. It provided several observational 'firsts,' like the detection of neutrinos from an exploding star, the observation of the progenitor star on archival photographic plates, the signatures of a non-spherical explosion, the direct observation of the radioactive elements produced during the blast, observation of the formation of dust in the supernova, as well as the detection of circumstellar and interstellar material. ESO PR Photo 08a/07 ESO PR Photo 08a/07 SN1987A in the Large Magellanic Cloud Today, it is exactly twenty years since the explosion of Supernova 1987A in the Large Magellanic Cloud was first observed, at a distance of 163,000 light-years. It was the first naked-eye supernova to be seen for 383 years. Few events in modern astronomy have met with such an enthusiastic response by the scientists and now, after 20 years, it continues to be an extremely exciting object that is further studied by astronomers around the world, in particular using ESO's telescopes. When the first signs of Supernova 1987A, the first supernova of the year 1987, were noticed early on 24 February of that year, it was clear that this would be an unusual event. It was discovered by naked-eye and on a panoramic photographic plate taken with a 10-inch astrograph on Las Campanas in Chile by Oscar Duhalde and Ian Shelton, respectively. A few hours earlier, still on 23 February, two large underground detectors - in Japan and the USA - had registered the passage of high-energy neutrinos. Since SN 1987A exploded in the Large Magellanic Cloud (LMC), it was only accessible to telescopes in the Southern Hemisphere, more particularly in Australia, South Africa, and South America. In Chile, ESO's observatory at La Silla with its armada of telescopes with sizes between 0.5 and 3.6-m, played an important role. ESO PR Photo 08c/07 ESO PR Photo 08c/07 The

  19. Electrodeposition and electrochemical characterisation of thick and thin coatings of Sb and Sb/Sb{sub 2}O{sub 3} particles for Li-ion battery anodes

    Energy Technology Data Exchange (ETDEWEB)

    Bryngelsson, Hanna; Eskhult, Jonas; Edstroem, Kristina; Nyholm, Leif [Department of Materials Chemistry, The Aangstroem Laboratory, Uppsala University, P.O. Box 538, SE-751 21 Uppsala (Sweden)

    2007-12-20

    The possibilities to electrodeposit thick coatings composed of nanoparticles of Sb and Sb{sub 2}O{sub 3} for use as high-capacity anode materials in Li-ion batteries have been investigated. It is demonstrated that the stability of the coatings depends on their Sb{sub 2}O{sub 3} concentrations as well as microstructure. The electrodeposition reactions in electrolytes with different pH and buffer capacities were studied using chronopotentiometry and electrochemical quartz crystal microbalance measurements. The obtained deposits, which were characterised with XRD and SEM, were also tested as anode materials in Li-ion batteries. The influence of the pH and buffer capacity of the deposition solution on the composition and particle size of the deposits were studied and it is concluded that depositions from a poorly buffered solution of antimony-tartrate give rise to good anode materials due to the inclusion of precipitated Sb{sub 2}O{sub 3} nanoparticles in the Sb coatings. Depositions under conditions yielding pure Sb coatings give rise to deposits composed of large crystalline particles with poor anode stabilities. The presence of a plateau at about 0.8 V versus Li{sup +}/Li due to SEI forming reactions and the origin of another plateau at about 0.4 V versus Li{sup +}/Li seen during the lithiation of thin Sb coatings are also discussed. It is demonstrated that the 0.4 V plateau is present for Sb coatings for which the (0 1 2) peak is the main peak in the XRD diffractogram. (author)

  20. Photoemission study of the skutterudite compounds CoSb sub 3 and RhSb sub 3

    CERN Document Server

    Ishii, H; Fujimori, A; Nagamoto, Y; Koyanagi, T; Sofo, J O

    2002-01-01

    We have studied the electronic structure of the skutterudite compounds CoSb sub 3 and Co(Sb sub 0 sub . sub 9 sub 6 Te sub 0 sub . sub 0 sub 4) sub 3 by photoemission spectroscopy. Valence-band spectra revealed that a significant amount Sb 5p states are present near the Fermi level and are hybridized with Co 3d states just below it. The spectra are well reproduced by the band-structure calculation, suggesting that the effect of electron correlations is not important. When Te is substituted for Sb and n-type carriers are doped into CoSb sub 3 , the spectra are shifted to higher binding energies as described by the rigid-band model. From this shift and the free-electron model for the conduction and valence bands, we have estimated the band gap of CoSb sub 3 to be 0.03-0.04 eV, consistent with transport measurements. Photoemission spectra of RhSb sub 3 have also been measured and revealed expected similarities to and differences from those of CoSb sub 3. Unusual temperature dependence has been observed for the s...

  1. Topological crystalline insulator SnTe nanoribbons

    Science.gov (United States)

    Dahal, Bishnu R.; Dulal, Rajendra P.; Pegg, Ian L.; Philip, John

    2017-03-01

    Topological crystalline insulators are systems in which a band inversion that is protected by crystalline mirror symmetry gives rise to nontrivial topological surface states. SnTe is a topological crystalline insulator. It exhibits p-type conductivity due to Sn vacancies and Te antisites, which leads to high carrier density in the bulk. Thus growth of high quality SnTe is a prerequisite for understanding the topological crystalline insulating behavior. We have grown SnTe nanoribbons using a solution method. The width of the SnTe ribbons varies from 500 nm to 2 μm. They exhibit rock salt crystal structure with a lattice parameter of 6.32 Å. The solution method that we have adapted uses low temperature, so the Sn vacancies can be controlled. The solution grown SnTe nanoribbons exhibit strong semiconducting behavior with an activation energy of 240 meV. This activation energy matches with the calculated band gap for SnTe with a lattice parameter of 6.32 Å, which is higher than that reported for bulk SnTe. The higher activation energy makes the thermal excitation of bulk charges very difficult on the surface. As a result, the topological surfaces will be free from the disturbance caused by the thermal excitations

  2. STRESS a SN survey at ESO

    Science.gov (United States)

    Botticella, M. T.

    We performed the Southern inTermediate Redshift ESO Supernova Search (STRESS), a survey specifically designed to measure the rate of both SNe Ia and CC SNe, in order to obtain a direct comparison of the high redshift and local rates and to investigate the dependence of the rates on specific galaxy properties, most notably their colour. We found that the type Ia SN rate, at mean redshift z = 0.3, is 0.22+0.10+0.16-0.08-0.14 h270 SNu, while the CC SN rate, at z = 0.21, is 0.82+0.31+0.300.24-0.26 h270 SNu. The quoted errors are the statistical and systematic uncertainties. With respect to the local value, the CC SN rate at z = 0.2 is higher by a factor of ˜ 2, whereas the type Ia SN rate remains almost constant. We also measured the SN rates in the red and blue galaxies and found that the SN Ia rate seems to be constant in galaxies of different colour, whereas the CC SN rate seems to peak in blue galaxies, as in the local Universe. Finally we exploited the link between SFH and SN rates to predict the evolutionary behaviour of the SN rates and compare it with the path indicated by observations.

  3. Auger recombination in {GaSb}/{AlSb} multi quantum well heterostructures

    Science.gov (United States)

    Zielinski, E.; Schweizer, H.; Griffiths, G.; Kroemer, H.; Subbanna, S.

    The experimental determination of Auger coefficients in {GaSb}/{AlSb} multi quantum well heterostructures is reported for the first time. The luminescence at E g and E g+ Δ0, recorded under the same experimental conditions, is used to monitor the carrier recombination channels. A quantitative determination of the recombination coefficients is achieved applying coupled carrier rate equations for the conduction and the valence subbands including the split-off valence band. Information on the actual carrier density is obtained by line shape analysis of the E g-emission. Two dimensional carrier densities up to 10 12cm -2 are determined. Auger coefficients exhibit a pronounced well width dependence: above 100Å C ˜- 4·10 -27s -1cm 6 whereas at 50Å values are 10 times smaller. No resonance of the Auger recombination is observed tuning the band gap energy over the spin-orbit splitting with temperature.

  4. Selective thermal transformation of old computer printed circuit boards to Cu-Sn based alloy.

    Science.gov (United States)

    Shokri, Ali; Pahlevani, Farshid; Cole, Ivan; Sahajwalla, Veena

    2017-09-01

    This study investigates, verifies and determines the optimal parameters for the selective thermal transformation of problematic electronic waste (e-waste) to produce value-added copper-tin (Cu-Sn) based alloys; thereby demonstrating a novel new pathway for the cost-effective recovery of resources from one of the world's fastest growing and most challenging waste streams. Using outdated computer printed circuit boards (PCBs), a ubiquitous component of e-waste, we investigated transformations across a range of temperatures and time frames. Results indicate a two-step heat treatment process, using a low temperature step followed by a high temperature step, can be used to produce and separate off, first, a lead (Pb) based alloy and, subsequently, a Cu-Sn based alloy. We also found a single-step heat treatment process at a moderate temperature of 900 °C can be used to directly transform old PCBs to produce a Cu-Sn based alloy, while capturing the Pb and antimony (Sb) as alloying elements to prevent the emission of these low melting point elements. These results demonstrate old computer PCBs, large volumes of which are already within global waste stockpiles, can be considered a potential source of value-added metal alloys, opening up a new opportunity for utilizing e-waste to produce metal alloys in local micro-factories. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. BETA DECAY HALF-LIVES AND RATES OF 134-136SN NUCLEI

    Directory of Open Access Journals (Sweden)

    M KHITER

    2015-12-01

    Full Text Available In astrophysical environment, allowed Gamow-Teller (GT transitions and space phase factors play an important role in determination of transition rates and half-lives, particularly for β-decay in presupernova evolution of massive stars. The estimation of these half-lives in neutron rich nuclei is needed in astrophysics for the understanding of supernovae explosions and the processes of nucleosynthesis, principally the r-process, and in the experimental exploration of the nuclear landscape. Their determination in agreement with experimental results is a challenging problem for nuclear theorists. In this work, the total β-decay half-lives and rates of 134-136Sn nuclei at different temperatures are calculated using various interactions developed in the light of recently available information on experimental binding energies and low-lying spectra of Sn, Sb and Te isotopes in 132Sn mass region. The calculation has been realized using Oxbash code in the frame work of the nuclear shell model. With these interactions, one can observe that the effective half-lives increase and the total decay rates decrease with increasing temperature. A deviation of half-lives starts at around 0.2 MeV and satures above 10 MeV, but the half-lives limit values are slightly different for all interactions.

  6. Unusual crystallization behavior in Ga-Sb phase change alloys

    Directory of Open Access Journals (Sweden)

    Magali Putero

    2013-12-01

    Full Text Available Combined in situ X-ray scattering techniques using synchrotron radiation were applied to investigate the crystallization behavior of Sb-rich Ga-Sb alloys. Measurements of the sheet resistance during heating indicated a reduced crystallization temperature with increased Sb content, which was confirmed by in situ X-ray diffraction. The electrical contrast increased with increasing Sb content and the resistivities in both the amorphous and crystalline phases decreased. It was found that by tuning the composition between Ga:Sb = 9:91 (in at.% and Ga:Sb = 45:55, the change in mass density upon crystallization changes from an increase in mass density which is typical for most phase change materials to a decrease in mass density. At the composition of Ga:Sb = 30:70, no mass density change is observed which should be very beneficial for phase change random access memory (PCRAM applications where a change in mass density during cycling is assumed to cause void formation and PCRAM device failure.

  7. SbSI Nanosensors: from Gel to Single Nanowire Devices.

    Science.gov (United States)

    Mistewicz, Krystian; Nowak, Marian; Paszkiewicz, Regina; Guiseppi-Elie, Anthony

    2017-12-01

    The gas-sensing properties of antimony sulfoiodide (SbSI) nanosensors have been tested for humidity and carbon dioxide in nitrogen. The presented low-power SbSI nanosensors have operated at relatively low temperature and have not required heating system for recovery. Functionality of sonochemically prepared SbSI nanosensors made of xerogel as well as single nanowires has been compared. In the latter case, small amount of SbSI nanowires has been aligned in electric field and bonded ultrasonically to Au microelectrodes. The current and photocurrent responses of SbSI nanosensors have been investigated as function of relative humidity. Mechanism of light-induced desorption of H2O from SbSI nanowires' surface has been discussed. SbSI nanosensors have been tested for concentrations from 51 to 10(6) ppm of CO2 in N2, exhibiting a low detection limit of 40(31) ppm. The current response sensitivity has shown a tendency to decrease with increasing CO2 concentration. The experimental results have been explained taking into account proton-transfer process and Grotthuss' chain reaction, as well as electronic theory of adsorption and catalysis on semiconductors.

  8. SbSI Nanosensors: from Gel to Single Nanowire Devices

    Science.gov (United States)

    Mistewicz, Krystian; Nowak, Marian; Paszkiewicz, Regina; Guiseppi-Elie, Anthony

    2017-02-01

    The gas-sensing properties of antimony sulfoiodide (SbSI) nanosensors have been tested for humidity and carbon dioxide in nitrogen. The presented low-power SbSI nanosensors have operated at relatively low temperature and have not required heating system for recovery. Functionality of sonochemically prepared SbSI nanosensors made of xerogel as well as single nanowires has been compared. In the latter case, small amount of SbSI nanowires has been aligned in electric field and bonded ultrasonically to Au microelectrodes. The current and photocurrent responses of SbSI nanosensors have been investigated as function of relative humidity. Mechanism of light-induced desorption of H2O from SbSI nanowires' surface has been discussed. SbSI nanosensors have been tested for concentrations from 51 to 106 ppm of CO2 in N2, exhibiting a low detection limit of 40(31) ppm. The current response sensitivity has shown a tendency to decrease with increasing CO2 concentration. The experimental results have been explained taking into account proton-transfer process and Grotthuss' chain reaction, as well as electronic theory of adsorption and catalysis on semiconductors.

  9. Measurement and theoretical analysis of the excitation functions for 3He induced reactions on natSn

    Science.gov (United States)

    Ali, B. M.; Al-Abyad, M.; Seddik, U.; El-Kameesy, S. U.; Ditrói, F.; Takács, S.; Tárkányi, F.

    2015-11-01

    Excitation functions of 3He induced nuclear reactions on natSn were measured up to 26 MeV using the stacked-foil technique, utilizing the MGC-20E cyclotron of ATOMKI. Using HPGe detector the following radioisotopes were identified: 116,117,118,119g,119m,121g,121m,123mTe, 115g,116m,117,118m,120m,122g,124gSb and 113g,117mSn. The experimental results are presented for the first time in this energy range. The results of theoretical calculations based on EMPIRE and TENDL library were compared with the present data. Integral yields for some isotopes were calculated.

  10. Measurement and theoretical analysis of the excitation functions for {sup 3}He induced reactions on {sup nat}Sn

    Energy Technology Data Exchange (ETDEWEB)

    Ali, B.M.; Al-Abyad, M.; Seddik, U. [Physics Department (Cyclotron Facility), Nuclear Research Centre, Atomic Energy Authority, Cairo 13759 (Egypt); El-Kameesy, S.U. [Physics Department, Faculty of Science, Ain Shams University, Cairo (Egypt); Ditrói, F.; Takács, S.; Tárkányi, F. [Institute for Nuclear Research (ATOMKI), Hungarian Academy of Sciences, Debrecen H4026 (Hungary)

    2015-11-01

    Excitation functions of {sup 3}He induced nuclear reactions on {sup nat}Sn were measured up to 26 MeV using the stacked-foil technique, utilizing the MGC-20E cyclotron of ATOMKI. Using HPGe detector the following radioisotopes were identified: {sup 116,117,118,119g,119m,121g,121m,123m}Te, {sup 115g,116m,117,118m,120m,122g,124g}Sb and {sup 113g,117m}Sn. The experimental results are presented for the first time in this energy range. The results of theoretical calculations based on EMPIRE and TENDL library were compared with the present data. Integral yields for some isotopes were calculated.

  11. Specific heat and Hall effect of the ferromagnetic Kondo lattice UCu0.9Sb2

    Science.gov (United States)

    Tran, V. H.; Bukowski, Z.

    2017-06-01

    We have investigated the electrical resistivity ρ, specific heat C p and Hall coefficient R H on a single crystal of a ferromagnetic Kondo lattice UCu0.9Sb2. The experimental ρ (T) , C p (T) and {{R}\\text{H}}(T) data evidence a bulk magnetic phase transition at {{T}\\text{C}}=113 K, and additionally exhibit an unexpected bump located in the temperature range T C/10-T C/3. UCu0.9Sb2 has an enhanced electronic specific heat coefficient γ ˜ 71 mJ molK-2, corresponding to Kondo temperature {{T}\\text{K}}˜ 6.8 K. An analysis of the Hall effect data for j//(a, b)-plane and H// c-axis reveals that the low-temperature ordinary Hall coefficient R 0 is positive, suggesting that p-type electrical conductivity is dominant. The density of the carriers at 2 K is about 0.6 holes f.u.-1, which may categorize the studied compound into class of low carrier density compounds. Combined γ and R 0 data divulge an effective mass of charge carriers {{m}\\ast}˜ 27 m e . This finding together with quite low Hall mobility {μ\\text{H}}=25 cm2 Vs-1 and Kadowaki-Woods ratio {{r}\\text{KW}}=0.98× ~{{10}-5} μ Ω cm (mol K2 mJ-1)2, manifest the development of heavy-fermion state in the ferromagnetic UCu0.9Sb2 compound at low temperatures.

  12. Agroecological Responses of Heavy Metal Pollution with Special Emphasis on Soil Health and Plant Performances

    OpenAIRE

    Vaibhav Srivastava; Abhijit Sarkar; Sonu Singh; Pooja Singh; Ademir S. F. Araujo; Rajeev P. Singh

    2017-01-01

    With modern day urbanization and industrialization, heavy metal (HM) contamination has become a prime concern for today's society. The impacts of metal contamination on agriculture range from the agricultural soil to the produce in our food basket. The heavy metals (HMs) and metalloids, including Cr, Mn, Co, Ni, Cu, Zn, Cd, Sn, Hg, Pb, among others, can result in significant toxic impacts. The intensification of agricultural land use and changes in farming practices along with technological a...

  13. A heavy load for heavy ions

    CERN Multimedia

    2003-01-01

    On 25 September, the two large coils for the dipole magnet of ALICE, the LHC experiment dedicated to heavy ions, arrived at Point 2 on two heavy load trucks after a 1200 km journey from their assembly in Vannes, France.

  14. Genotoxicity of 11 heavy metals detected as food contaminants in two human cell lines.

    Science.gov (United States)

    Kopp, B; Zalko, D; Audebert, M

    2017-11-18

    Heavy metals, such as arsenic (As), antimony (Sb), barium (Ba), cadmium (Cd), cobalt (Co), germanium (Ge), lead (Pb), nickel (Ni), tellurium (Te), and vanadium (V) are widely distributed in the environment and in the food chain. Human exposure to heavy metals through water and food has been reported by different international agencies. Although some of these heavy metals are essential elements for human growth and development, they may also be toxic at low concentrations due to indirect mechanisms. In this study, the genotoxic and cytotoxic properties of 15 different oxidation statuses of 11 different heavy metals were investigated using high-throughput screening (γH2AX assay) in two human cell lines (HepG2 and LS-174T) representative of target organs (liver and colon) for food contaminants. Base on their lowest observed adverse effect concentration, the genotoxic potency of each heavy metal in each cell line was ranked in decreasing order, NaAsO2  > CdCl2  > PbCl2 (only in LS-174T cells) > As2 O5  > SbCl3  > K2 TeO3  > As2 O3 . No significant genotoxicity was observed with the other heavy metals tested. Cell viability data indicate that several heavy metals (As, Cd, Co, Ni, Sb, and Te) induce cytotoxicity at high concentrations, whereas an increase in the number of cells was observed for lead concentrations >100 µM in both cell lines tested, suggesting that lead stimulates cell growth. All these results highlight the possible human health hazards associated with the presence of heavy metals present in food. Environ. Mol. Mutagen., 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  15. Evaluation of heavy metals in atmospheric emissions from automotive industry by total reflection X-ray fluorescence with synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Silvana; Weber Neto, Jose, E-mail: silvana@fec.unicamp.b [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Engenharia Civil, Arquitetura e Urbanismo. Dept. de Saneamento e Ambiente; Vives, Ana Elisa Sirito de, E-mail: aesvives@unimep.b [Universidade Metodista de Piracicaba (UNIMEP), Santa Barbara D' Oeste, SP (Brazil). Faculdade de Engenharia, Arquitetura e Urbanismo

    2009-07-01

    This study had as goal to determine heavy metals and other elements (Ba, Br, Ca, Pb, Cl, Cr, Sr, Fe, Mn, Ni, K, Si, Ti and Zn) in atmospheric pollutants generated by an automotive industry located in the city of Engenheiro Coelho, state of Sao Paulo, Brazil. The sampling and sample preparation procedures were based on methods established by the Company of Sanitation and Technology (CETESB L9.234) and also by the Environmental Protection Agency (EPA - Method 29). The analysis was performed at XRF Beamline (D09B-XRF) in the Synchrotron Light Source Laboratory (Campinas/SP). A white beam of synchrotron radiation was used for sample and standard excitation which were irradiated by 100 seconds. For X-ray lines detection, a Ge (HP) detector with 150 eV of resolution at 5.9 keV was employed. For zinc, iron, barium, calcium and potassium, the values obtained were in the range of 30 mg/Nm{sup 3} and, for other elements, the concentrations were approximately 1 mg/Nm{sup 3}. The sum of As, Be, Co, Cr, Cu, Mn, Ni, Pb, Sb, Se, Sn, Te and Zn concentration was compared with the limits established by CONAMA 264/1999 and SEMA 041/2002 resolutions (7.0 mg/Nm{sup 3}) and it was observed that, for all samples, sums are higher than the permissive value mainly due to the high concentration of zinc. Detection limits for SR-TXRF technique were 0.10 mug/Nm{sup 3} for Pb and 0.02 mug/Nm{sup 3} for Zn. (author)

  16. Modelling And Manufacturing GaSb TPV Converters

    Science.gov (United States)

    Algora, Carlos; Martín, Diego

    2003-01-01

    A complete model for GaSb TPV converters considering multiple real conditions (spectra, temperature, ARC, size, number and characteristics of grid fingers, size of busbar, etc.) is presented. The model has been applied to GaSb TPV converters fabricated in our laboratory by single zinc diffusion. The agreement between theory and experiments is very good. Future guides of performance improvement like the passivation of the surface together with the correspondent structure optimisation and the achievement of a better GaSb quality available more widespread are suggested.

  17. Point defect balance in epitaxial GaSb

    Energy Technology Data Exchange (ETDEWEB)

    Segercrantz, N., E-mail: natalie.segercrantz@aalto.fi; Slotte, J.; Makkonen, I.; Kujala, J.; Tuomisto, F. [Department of Applied Physics, Aalto University, P.O. Box 14100, FIN-00076 Aalto Espoo (Finland); Song, Y.; Wang, S. [Department of Microtechnology and Nanoscience, Chalmers University of Technology, 41296 Göteborg (Sweden); State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences 865 Changning Road, Shanghai 200050 (China)

    2014-08-25

    Positron annihilation spectroscopy in both conventional and coincidence Doppler broadening mode is used for studying the effect of growth conditions on the point defect balance in GaSb:Bi epitaxial layers grown by molecular beam epitaxy. Positron annihilation characteristics in GaSb are also calculated using density functional theory and compared to experimental results. We conclude that while the main positron trapping defect in bulk samples is the Ga antisite, the Ga vacancy is the most prominent trap in the samples grown by molecular beam epitaxy. The results suggest that the p–type conductivity is caused by different defects in GaSb grown with different methods.

  18. Heavy Menstrual Bleeding

    Science.gov (United States)

    ... can cause heavy bleeding. • Medications—Blood thinners and aspirin can cause heavy menstrual bleeding. The copper intrauterine ... on the ovaries, fallopian tubes, and other pelvic structures. Endometrium: The lining of the uterus. Fibroids: Growths, ...

  19. Studying superconducting Nb3Sn wire

    CERN Multimedia

    AUTHOR|(CDS)2099575

    2015-01-01

    Studying superconducting Nb3Sn wire. From the current experience from LHC and HL-LHC we know that the performance requirements for Nb3Sn conductor for future circular collider are challenging and should exceed that of present state-of-the-art materials.

  20. Fast reversible laser-induced crystallization of Sb-rich Zn-Sb-Se phase change material with excellent stability

    Directory of Open Access Journals (Sweden)

    Yimin Chen

    2015-07-01

    Full Text Available We present a new reversible phase-change medium Sb-rich Zn-Sb-Se film, which possesses a large difference in both optical and electrical constant. The doped-ZnSb, sub-formed Zn-Se, and exhausted Sb-Se3/2 co-influence the physical properties. Typically, there is ∼105 resistance ratio and ∼14% relative reflectivity change in Zn19Sb45.7Se35.3 film when switched by electricity or laser pulses between amorphous and crystalline states. The higher Tc (∼250°C, larger Ea (∼8.57eV, better 10-yr data retention (∼200.2°C, higher crystallization resistance (∼3 × 103Ω/□ at 300°C-annealled and relative lower melting temperature (∼550.2°C are exhibited in Zn19Sb45.7Se35.3 film. Importantly, a short crystalline time (∼80ns at 70mW of the ideal Zn19Sb45.7Se35.3 film can be obtained without sacrificing room-temperature stability.

  1. Electronic structure of GaSb/GaAs and Si/Ge quantum dots

    CERN Document Server

    North, S M

    2001-01-01

    There are significant differences between experiment and theoretical calculations of the electronic structure of GaSb/GaAs self-assembled quantum dots. Using a multi-band effective mass approximation it is shown that the influence of size and geometry of quantum dots has little or no effect in determining the hydrostatic strain. Furthermore, the valence-band ground state energies of the quantum dots studied are surprisingly consistent. This apparent paradox attributed to the influence of biaxial strain in shaping the heavy-hole and light-hole potentials. Consequently, it is shown that a simple, hydrostatically derived potential is insufficient to accurately describe the electronic structure of such quantum dots. In addition, using the latest experimental results measuring the conduction-band offset, it has been shown that much better experimental contact may be achieved for the magnitude of the transition energies derived compared to theoretically derived transition energies. The transition energies of Si/Ge ...

  2. Laser spectroscopy of neutron deficient Sn isotopes

    CERN Multimedia

    We propose to study the ground state properties of neutron-deficient Sn isotopes towards the doubly-magic nucleus $^{100}$Sn. Nuclear spins, changes in the rms charge radii and electromagnetic moments of $^{101-121}$Sn will be measured by laser spectroscopy using the CRIS experimental beam line. These ground-state properties will help to clarify the evolution of nuclear structure properties approaching the $\\textit{N = Z =}$ 50 shell closures. The Sn isotopic chain is currently the frontier for the application of state-of-the-art ab-initio calculations. Our knowledge of the nuclear structure of the Sn isotopes will set a benchmark for the advances of many-body methods, and will provide an important test for modern descriptions of the nuclear force.

  3. Cationic Site-Preference in the Yb14-xCaxAlSb11 (4.81 ≤ x ≤ 10.57 Series: Theoretical and Experimental Studies

    Directory of Open Access Journals (Sweden)

    Gnu Nam

    2016-07-01

    Full Text Available Four quaternary Zintl phases with mixed-cations in the Yb14-xCaxAlSb11 (4.81 ≤ x ≤ 10.57 series have been synthesized by using the arc-melting and the Sn metal-flux reaction methods, and the isotypic crystal structures of the title compounds have been characterized by both powder and single-crystal X-ray diffraction (PXRD and SXRD analyses. The overall crystal structure adopting the Ca14AlSb11-type can be described as a pack of four different types of the spiral-shaped one-dimensional octahedra chains with various turning radii, each of which is formed by the distorted ((Yb/CaSb6 octahedra. Four symmetrically-independent cationic sites contain mixed occupations of Yb2+ and Ca2+ with different mixing ratios and display a particular site preference by two cationic elements. Two hypothetical structural models of Yb4Ca10AlSb11 with different cationic arrangements were designed and exploited to study the details of site and bond energies. QVAL values provided the rationale for the observed site preference based on the electronegativity of each atom. Density of states (DOS curves indicated a semiconducting property of the title compounds, and crystal orbital Hamilton population (COHP plots explained individual chemical bonding between components. Thermal conductivity measurement was performed for Yb8.42(4Ca5.58AlSb11, and the result was compared to compounds without mixed cations.

  4. Application of 119Sn CPMG MAS NMR for Fast Characterization of Sn Sites in Zeolites with Natural 119Sn Isotope Abundance

    DEFF Research Database (Denmark)

    G. Kolyagin, Yury; V. Yakimo, Alexander; Tolborg, Søren

    2016-01-01

    119Sn CPMG MAS NMR is demonstrated to be a fast and efficient method for characterization of Sn-sites in Sn-containing zeolites. Tuning of the CPMG echo-train sequence decreases the experimental time by a factor of 5–40 in the case of as-synthesized and hydrated Sn-BEA samples and by 3 orders......-BEA zeolites with natural 119Sn isotope abundance using conventional MAS NMR equipment....

  5. Secondary ion emission from A sup I sup I sup I B sup V compound semiconductors under MeV-energy heavy ion bombardment

    CERN Document Server

    Ninomiya, S; Nagai, M; Nakata, Y; Imai, M; Imanishi, N

    2003-01-01

    Mass and yields of secondary ions emitted from GaP, GaAs, GaSb and InSb targets bombarded by MeV-energy heavy ion have been investigated. Obtained feature of the secondary ion emission depends characteristically on the target species. Molecular and small cluster ions were emitted from the GaP and GaAs targets. On the other hand, pretty large cluster ions were emitted from the GaSb and InSb targets. Yields of clusters from the GaSb target increase with increasing the incident energy and decrease exponentially with the cluster size, while yields from the InSb target keep constant or decrease gently with increasing the incident energy and show the power law dependence on the cluster size. These results show that cluster ions from the GaSb target are formed through a coagulation of small molecules emitted from the target in the selvage region near the surface, and those from the InSb target are emitted directly from the surface as cluster.

  6. Sb{sub 7}Te{sub 3}/ZnSb multilayer thin films for high thermal stability and long data retention phase-change memory

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Shiyu; Wu, Weihua [Functional Materials Research Laboratory, School of Materials Science & Engineering, Tongji University, Shanghai 201804 (China); Zhai, Jiwei, E-mail: apzhai@tongji.edu.cn [Functional Materials Research Laboratory, School of Materials Science & Engineering, Tongji University, Shanghai 201804 (China); Song, Sannian; Song, Zhitang [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Micro-system and Information Technology, Chinese Academy of Science, Shanghai 200050 (China)

    2017-04-15

    Highlights: • Sb{sub 7}Te{sub 3} (ST) provides a fast crystallization speed, low melting temperature. • The Sb{sub 7}Te{sub 3}/ZnSb films exhibits faster crystallization speed, high thermal stability. • The calculated temperature for 10-year data retention is about 127 {sup o}C. • The Sb{sub 7}Te{sub 3}/ZnSb multilayer configuration with low power consumption. - Abstract: Phase-change memory is regard as one of the most promising candidates for the next-generation non-volatile memory. In this work, we proposed a Sb{sub 7}Te{sub 3}/ZnSb multilayer thin films to improve the thermal stability of Sb-rich Sb{sub 3}Te{sub 7}. The sheet resistance ratio between amorphous and crystalline states reached up to 4 orders of magnitude. With regard to the thermal stability, the calculated temperature for 10-year data retention is about 127 °C. The threshold current and threshold voltage of a cell based on Sb{sub 7}Te{sub 3}/ZnSb are 6.9 μA and 1.9 V, respectively. The lower RESET power is presented in the PCM cells of Sb{sub 7}Te{sub 3}/ZnSb films, benefiting from its high resistivity.

  7. Photochemical epoxidation of olefins by visible light in a redox system involving Sb(V) tetraphenylporphyrin and water

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Haruo; Hida, Mitsuhiko (Tokyo Metropolitan Univ. (Japan))

    1989-03-25

    The authors explore electron donors from the viewpoint of solar energy storage. Much attention has been focused on how a water molecule can be incorporated into electron donor system. In this paper, the authors describe a photochemical epoxidation of alkene sensitized by Sb(V)-, P(V)-, Sn(IV)-, Ge(IV)- tetraphenylporphyrin (TPP) with higher oxidation potential than 1.0 Volts vs. NHE in redox systems with a water molecule as an electron donor. The water molecule acts as an electron donor, and alkene acts as an oxygen atom acceptor in this photoredox system. Epoxidation of alkenes usually requires strong oxidizing agents either by the thermal or photochemical method. This is the first example of the photochemical epoxide formation from alkene and water without any strong oxidizing agent. 1 fig.

  8. Stability and electronic properties of hybrid SnO bilayers: SnO/graphene and SnO/BN

    Science.gov (United States)

    Guo, Qing; Wang, Gaoxue; Kumar, Ashok; Pandey, Ravindra

    2017-11-01

    Van der Waals structures based on two-dimensional materials have been considered as promising structures for novel nanoscale electronic devices. Two-dimensional SnO films which display intrinsic p-type semiconducting properties were fabricated recently. In this paper, we consider vertically stacked heterostructures consisting of a SnO monolayer with graphene or a BN monolayer to investigate their stability, electronic and transport properties using density functional theory. The calculated results find that the properties of the constituent monolayers are retained in these SnO-based heterostructures, and a p-type Schottky barrier is formed in the SnO/graphene heterostructure. Additionally, the Schottky barrier can be effectively controlled with an external electric field, which is useful characteristic for the van der Waals heterostructure-based electronic devices. In the SnO/BN heterostructure, the electronic properties of SnO are least affected by the insulating monolayer suggesting that the BN monolayer would be an ideal substrate for SnO-based nanoscale devices.

  9. grain size and heavy mineral analyses of two boreholes in recent to ...

    African Journals Online (AJOL)

    user

    Grain size and heavy mineral analyses were carried out on the soil samples collected from the boreholes at an interval of. 15ft. The results obtained indicate that the ..... well are slightly more rounded than those from. Okabere well; this indicates that Okabere well is closer. S/N. Depth (ft). Lithology. Colour. Shape. 1. 0-15.

  10. Hidden edge Dirac point and robust quantum edge transport in InAs/GaSb quantum wells

    Science.gov (United States)

    Li, Chang-An; Zhang, Song-Bo; Shen, Shun-Qing

    2018-01-01

    The robustness of quantum edge transport in InAs/GaSb quantum wells in the presence of magnetic fields raises an issue on the fate of topological phases of matter under time-reversal symmetry breaking. A peculiar band structure evolution in InAs/GaSb quantum wells is revealed: the electron subbands cross the heavy hole subbands but anticross the light hole subbands. The topologically protected band crossing point (Dirac point) of the helical edge states is pulled to be close to and even buried in the bulk valence bands when the system is in a deeply inverted regime, which is attributed to the existence of the light hole subbands. A sizable Zeeman energy gap verified by the effective g factors of edge states opens at the Dirac point by an in-plane or perpendicular magnetic field; however, it can also be hidden in the bulk valance bands. This provides a plausible explanation for the recent observation on the robustness of quantum edge transport in InAs/GaSb quantum wells subjected to strong magnetic fields.

  11. Design, fabrication, and characterization of InSb avalanche photodiode

    Science.gov (United States)

    Abautret, J.; Evirgen, A.; Perez, J. P.; Christol, P.; Rouvié, A.; Cluzel, R.; Cordat, A.; Rothman, J.

    2013-12-01

    In this communication, the potentiality of InSb material as an avalanche photodiode (APD) device is investigated. Current density-voltage (J-V) characteristics at 77K of InSb pin photodiodes were simulated by using ATLAS software from SILVACO, in dark conditions and under illumination. In order to validate parameter values used for the modeling, theoretical J-V results were compared with experimental measurements performed on InSb diodes fabricated by molecular beam epitaxy. Next, assuming a multiplication process only induced by the electrons (e-APD), different designs of separate absorption and multiplication (SAM) APD structure were theoretically investigated and the first InSb SAM APD structure with 1μm thick multiplication layer was then fabricated and characterized.

  12. Modeling the AgInSbTe Memristor

    Directory of Open Access Journals (Sweden)

    J. Yu

    2015-09-01

    Full Text Available The AgInSbTe memristor shows gradual resistance tuning characteristics, which makes it a potential candidate to emulate biological plastic synapses. The working mechanism of the device is complex, and both intrinsic charge-trapping mechanism and extrinsic electrochemical metallization effect are confirmed in the AgInSbTe memristor. Mathematical model of the AgInSbTe memristor has not been given before. We propose the flux-voltage controlled memristor model. With piecewise linear approximation technique, we deliver the flux-voltage controlled memristor model of the AgInSbTe memristor based on the experiment data. Our model fits the data well. The flux-voltage controlled memristor model and the piecewise linear approximation method are also suitable for modeling other kinds of memristor devices based on experiment data.

  13. Hall Mobility of Amorphous Ge2Sb2Te5

    National Research Council Canada - National Science Library

    Baily, S. A; Emin, David; Li, Heng

    2006-01-01

    The electrical conductivity, Seebeck coefficient, and Hall coefficient of 3 micron thick films of amorphous Ge2Sb2Te5 have been measured as functions of temperature from room temperature down to as low as 200 K...

  14. Monte Carlo calculation of electron transport in InSb

    CERN Document Server

    Mallick, P S

    2002-01-01

    The velocity field characteristics of InSb have been obtained at 77 K by the Monte Carlo simulation technique. The results agree with the experimental data and also with those obtained by using the displaced Maxwellian distribution function. The effects of the various simulation parameters as well as that of the ionized impurity concentration on the mobility values for InSb have been discussed and results presented. (author)

  15. 119Sn Mössbauer studies on ferromagnetic and photocatalytic Sn-TiO2 nanocrystals

    Science.gov (United States)

    Ganeshraja, Ayyakannu Sundaram; Nomura, Kiyoshi; Wang, Junhu

    2016-12-01

    Diluted Sn doped TiO2 nanocrystals (Sn/Ti ratio: x ≤ 1.37 %) were synthesized by a simple hydrothermal method using pure reagents without any surfactant and dispersant material. The XRD of these samples showed an anatase phase, anatase and rutile mixed phases, and a rutile phase of TiO2 and SnO2 with the increase of Sn dopant concentrations. 119Sn Mössbauer spectra gave the broad peaks, which were decomposed into doublets and sextets because almost all these samples showed magnetic hysteresis even at room temperature. The titanium oxides doped with x ≤ 0.12 % showed the relatively large magnetic hysteresis and high photocatalytic activity. Mössbauer spectra of samples doped with x > 0.3 % were analyzed by one doublet and two sextets although the samples showed weak ferromagnetism. Three kinds of Sn species may be distinguished as Sn 4+ substituted TiO2 and two different magnetic arrangements of Sn doped TiO2: one with more oxygen defects and other at the interface of TiO2 and precipitated SnO2 containing Ti atoms. The correlation between various amounts of Sn sites and photocatalytic activity and/ or magnetic property was discussed.

  16. Design of Reduction Process of SnO2 by CH4 for Efficient Sn Recovery.

    Science.gov (United States)

    Ha, Hyunwoo; Yoo, Mi; An, Hyesung; Shin, Kihyun; Han, Taeyang; Sohn, Youhan; Kim, Sangyeol; Lee, Sang-Ro; Han, Jun Hyun; Kim, Hyun You

    2017-10-31

    We design a novel method for the CH4 reduction of SnO2 for the efficient recovery of Sn from SnO2 through a study combining theory and experiment. The atomic-level process of CH4-SnO2 interaction and temperature-dependent reduction behavior of SnO2 were studied with a combination of a multi-scale computational method of thermodynamic simulations and density functional theory (DFT) calculations. We found that CH4 was a highly efficient and a versatile reducing agent, as the total reducing power of CH4 originates from the carbon and hydrogen of CH4, which sequentially reduce SnO2. Moreover, as a result of the CH4 reduction of SnO2, a mixture of CO and H2 was produced as a gas-phase product (syngas). The relative molar ratio of the produced gas-phase product was controllable by the reduction temperature and the amount of supplied CH4. The laboratory-scale experimental study confirmed that CH4 actively reduces SnO2, producing 99.34% high-purity Sn and H2 and CO. Our results present a novel method for an efficient, green, and economical recycling strategy for Sn with economic value added that is held by the co-produced clean energy source (syngas).

  17. Etanercept (SB4): A Review in Autoimmune Inflammatory Diseases.

    Science.gov (United States)

    Burness, Celeste B; Duggan, Sean T

    2016-08-01

    Etanercept (SB4) [Benepali(®)], a tumour necrosis factor inhibitor that is a biosimilar of reference etanercept (Enbrel(®)), is approved in the EU for use in all adult indications for which reference etanercept is approved, namely rheumatoid arthritis, axial spondyloarthritis (ankylosing spondylitis and non-radiographic axial spondyloarthritis), psoriatic arthritis, and plaque psoriasis. The approval of etanercept (SB4) was based on the results of stringent comparability exercises designed to demonstrate similarity to reference etanercept in terms of quality, biological activity, efficacy, safety, and immunogenicity. In two well-designed clinical trials, etanercept (SB4) was equivalent to reference etanercept with regard to pharmacokinetic properties in healthy volunteers and in terms of efficacy in patients with moderate to severe rheumatoid arthritis despite methotrexate therapy. Longer-term efficacy (up to 52 weeks) was also similar in both treatment groups. Etanercept (SB4) was generally well tolerated, with a similar safety profile to that of reference etanercept. Preliminary results of the open-label extension period (100 weeks) suggest that transitioning from reference etanercept to etanercept (SB4) was associated with sustained efficacy and no change in the adverse event profile or immunogenicity. In conclusion, etanercept (SB4) provides therapeutically equivalent alternative in adult patients with autoimmune inflammatory diseases requiring treatment with etanercept.

  18. High Current Density InAsSb/GaSb Tunnel Field Effect Transistors

    OpenAIRE

    Dey, Anil; Borg, Mattias; Ganjipour, Bahram; Ek, Martin; Dick Thelander, Kimberly; Lind, Erik; Nilsson, Peter; Thelander, Claes; Wernersson, Lars-Erik

    2012-01-01

    Steep-slope devices, such as tunnel field-effect transistors (TFETs), have recently gained interest due to their potential for low power operation at room temperature. The devices are based on inter-band tunneling which could limit the on-current since the charge carriers must tunnel through a barrier to traverse the device. The InAs/GaSb heterostructure forms a broken type II band alignment which enables inter-band tunneling without a barrier, allowing high on-currents. We ha...

  19. Ferro electrical properties of GeSbTe thin films; Propiedades ferroelectricas de peliculas delgadas de GeSbTe

    Energy Technology Data Exchange (ETDEWEB)

    Gervacio A, J. J.; Prokhorov, E.; Espinoza B, F. J., E-mail: jgervacio@qro.cinvestav.m [IPN, Centro de Investigacion y de Estudios Avanzados, Unidad Queretaro, Libramiento Norponiente No. 2000, Juriquilla, 76230 Queretaro (Mexico)

    2011-07-01

    The aim of this work is to investigate and compare ferro electrical properties of thin GeSbTe films with composition Ge{sub 4}Sb{sub 1}Te{sub 5} (with well defined ferro electrical properties) and Ge{sub 2}Sb{sub 2}Te{sub 5} using impedance, optical reflection, XRD, DSc and Piezo response Force Microscopy techniques. The temperature dependence of the capacitance in both materials shows an abrupt change at the temperature corresponding to ferroelectric-paraelectric transition and the Curie-Weiss dependence. In Ge{sub 2}Sb{sub 2}Te{sub 5} films this transition corresponds to the end from a NaCl-type to a hexagonal transformation. Piezo response Force Microscopy measurements found ferroelectric domains with dimension approximately equal to the dimension of grains. (Author)

  20. Role of interlayer coupling for the power factor of CuSbS2 and CuSbSe2

    KAUST Repository

    Alsaleh, Najebah Mohammed Abdullah

    2017-01-08

    The electronic and transport properties of bulk and monolayer CuSbS2 and CuSbSe2 are determined by using density functional theory and semiclassical Boltzmann transport theory, in order to investigate the role of interlayer coupling for the thermoelectric properties. The calculated band gaps of the bulk compounds are in agreement with experiments and significantly higher than those of the monolayers, which thus show lower Seebeck coefficients. Since also the electrical conductivity is lower, the monolayers are characterized by lower power factors. Therefore, interlayer coupling is found to be essential for the excellent thermoelectric response of CuSbS2 and CuSbSe2, even though it is weak.

  1. Role of interlayer coupling for the power factor of CuSbS2 and CuSbSe2

    KAUST Repository

    Alsaleh, Najebah M.

    2016-09-26

    The electronic and transport properties of bulk and monolayer CuSbS2 and CuSbSe2 are determined by using density functional theory and semiclassical Boltzmann transport theory, in order to investigate the role of interlayer coupling for the thermoelectric properties. The calculated band gaps of the bulk compounds are in agreement with experiments and significantly higher than those of the monolayers, which thus show lower Seebeck coefficients. Since also the electrical conductivity is lower, the monolayers are characterized by lower power factors. Therefore, interlayer coupling is found to be essential for the excellent thermoelectric response of CuSbS2 and CuSbSe2, even though it is weak.

  2. Magnetic properties of GdPdSb and GdNiSb studied by {sup 155}Gd-Moessbauer spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Bielemeier, B. [Department Physik, Universitaet Paderborn, D-33098 Paderborn (Germany); Wortmann, G. [Department Physik, Universitaet Paderborn, D-33098 Paderborn (Germany)], E-mail: Wortmann@physik.upb.de; Casper, F.; Ksenofontov, V.; Felser, C. [Institut fuer Anorg. und Analyt. Chemie, Johannes Gutenberg-Universitaet, D-55099 Mainz (Germany)

    2009-07-01

    {sup 155}Gd-Moessbauer spectroscopy was applied to study the magnetic properties of GdPdSb with hexagonal LiGaGe structure and of GdNiSb in the cubic MgAgAs-type structure as well as in the hexagonal AlB{sub 2}-type structure. In GdPdSb magnetic ordering is observed at 13.0 K with indications of a tilted spin structure at lower temperatures. In the cubic phase of GdNiSb magnetic ordering is observed at 9.5 K and in the hexagonal phase around 3.5 K. These results are discussed in conjunction with previous investigations of these samples.

  3. Crystal structure, magnetism, {sup 89}Y solid state NMR, and {sup 121}Sb Moessbauer spectroscopic investigations of YIrSb

    Energy Technology Data Exchange (ETDEWEB)

    Benndorf, Christopher [Institut fuer Physikalische Chemie, Universitaet Muenster (Germany); Institut fuer Anorganische und Analytische Chemie, Universitaet Muenster (Germany); Heletta, Lukas; Block, Theresa; Poettgen, Rainer [Institut fuer Anorganische und Analytische Chemie, Universitaet Muenster (Germany); Eckert, Hellmut [Institut fuer Physikalische Chemie, Universitaet Muenster (Germany); Institute of Physics in Sao Carlos, University of Sao Paulo, Sao Carlos (Brazil)

    2017-02-15

    The ternary antimonide YIrSb was synthesized from the binary precursor YIr and elemental antimony by a diffusion controlled solid-state reaction. Single crystals were obtained by a flux technique with elemental bismuth as an inert solvent. The YIrSb structure (TiNiSi type, space group Pnma) was refined from single-crystal X-ray diffractometer data: a = 711.06(9), b = 447.74(5), c = 784.20(8) pm, wR{sub 2} = 0.0455, 535 F{sup 2} values, 20 variables. {sup 89}Y solid state MAS NMR and {sup 121}Sb Moessbauer spectra show single resonance lines in agreement with single-crystal X-ray data. YIrSb is a Pauli paramagnet. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  4. The antimony-group 11 chemical bond: dissociation energies of the diatomic molecules CuSb, AgSb, and AuSb.

    Science.gov (United States)

    Carta, V; Ciccioli, A; Gigli, G

    2014-02-14

    The intermetallic molecules CuSb, AgSb, and AuSb were identified in the effusive molecular beam produced at high temperature under equilibrium conditions in a double-cell-like Knudsen source. Several gaseous equilibria involving these species were studied by mass spectrometry as a function of temperature in the overall range 1349-1822 K, and the strength of the chemical bond formed between antimony and the group 11 metals was for the first time measured deriving the following thermochemical dissociation energies (D°(0), kJ/mol): 186.7 ± 5.1 (CuSb), 156.3 ± 4.9 (AgSb), 241.3 ± 5.8 (AuSb). The three species were also investigated computationally at the coupled cluster level with single, double, and noniterative quasiperturbative triple excitations (CCSD(T)). The spectroscopic parameters were calculated from the potential energy curves and the dissociation energies were evaluated at the Complete Basis Set limit, resulting in an overall good agreement with experimental values. An approximate evaluation of the spin-orbit effect was also performed. CCSD(T) calculations were further extended to the corresponding group 11 arsenide species which are here studied for the first time and the following dissociation energies (D°(0), kJ/mol): 190 ± 10 (CuAs), 151 ± 10 (AgAs), 240 ± 15 (AuAs) are proposed. Taking advantage of the new experimental and computational information here presented, the bond energy trends along group 11 and 4th and 5th periods of the periodic table were analyzed and the bond energies of the diatomic species CuBi and AuBi, yet experimentally unobserved, were predicted on an empirical basis.

  5. [Study on canopy spectral characteristics of paddy polluted by heavy metals].

    Science.gov (United States)

    Ren, Hong-Yan; Zhuang, Da-Fang; Pan, Jian-Jun; Shi, Xue-Zheng; Shi, Run-He; Wang, Hong-Jie

    2010-02-01

    Because of frequent mining, heavy metals are brought into environment like soils, water and atmosphere, resulting heavy metal contamination in the agricultural region beside mines. Heavy metals contamination causes vegetation stress like destruction of chloroplast structure, chlorophyll content decrease, blunt photosynthesis, etc. Spectral responses to changes in chlorophyll content and photosynthesis make it possible that remote sensing is applied in monitoring heavy metals stress on paddy plants. Field spectroradiometer was used to acquire canopy reflectance spectra of paddy plants contaminated by heavy metals released from local mining. The present study was conducted to (1) investigate discrimination of canopy reflectance spectra of heavy metal polluted and normal paddy plants; (2) extract spectral characteristics of contaminated paddy plants and compare them. By means of correlation analysis, sensitive bands (SB) were firstly picked out from canopy spectra. Secondly, on the basis of these sensitive bands, normalized difference vegetation indices (NDVI) were established, and then red edge position (REP) was extracted from canopy spectra via curve fitting of inverted Gaussian model. As a result of correlation analysis, 460, 560, 660 and 1 100 nm were considered respectively as sensitive band for Pb, Zn, Cu and As concentration in paddy leaves. Furthermore, heavy metal concentrations (Pb, Zn, Cu and As) were significantly correlated with NDVIs (Pb, NDV(510, 810); Zn, NDVI(510, 870; Cu, NDVI(660, 870); As, NDVI(510, 810)). Heavy metals were also significantly correlated with REP, however, the inflexion termed as spectral critical value (SCV) between low and high heavy metals concentrations should be considered during applying REP in remote sensing monitoring. Moreover, NDVI and REP are much better than SB in terms of capability of expressing spectral information. Therefore, heavy metals contamination in paddy plants can be remotely monitored via ground

  6. Monodisperse and inorganically capped Sn and Sn/SnO2 nanocrystals for high-performance Li-ion battery anodes.

    Science.gov (United States)

    Kravchyk, Kostiantyn; Protesescu, Loredana; Bodnarchuk, Maryna I; Krumeich, Frank; Yarema, Maksym; Walter, Marc; Guntlin, Christoph; Kovalenko, Maksym V

    2013-03-20

    We report a facile synthesis of highly monodisperse colloidal Sn and Sn/SnO2 nanocrystals with mean sizes tunable over the range 9-23 nm and size distributions below 10%. For testing the utility of Sn/SnO2 nanocrystals as an active anode material in Li-ion batteries, a simple ligand-exchange procedure using inorganic capping ligands was applied to facilitate electronic connectivity within the components of the nanocrystalline electrode. Electrochemical measurements demonstrated that 10 nm Sn/SnO2 nanocrystals enable high Li insertion/removal cycling stability, in striking contrast to commercial 100-150 nm powders of Sn and SnO2. In particular, reversible Li-storage capacities above 700 mA h g(-1) were obtained after 100 cycles of deep charging (0.005-2 V) at a relatively high current of 1000 mA h g(-1).

  7. Investigations of interfacial reactions of Sn-Zn based and Sn-Ag-Cu lead-free solder alloys as replacement for Sn-Pb solder

    Energy Technology Data Exchange (ETDEWEB)

    Islam, M.N. [Department of Electronic Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon Tong, Hong Kong (China); Chan, Y.C. [Department of Electronic Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon Tong, Hong Kong (China)]. E-mail: eeycchan@cityu.edu.hk; Rizvi, M.J. [Department of Electronic Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon Tong, Hong Kong (China); Jillek, W. [Department of EFI, Georg Simon Ohm University of Applied Science, 10 Wassertorstrasse, 90489 Nuernberg (Germany)

    2005-09-01

    The interfacial reactions of Sn-Zn based solders and a Sn-Ag-Cu solder have been compared with a eutectic Sn-Pb solder. During reflow soldering different types of intermetallic compounds (IMCs) are found at the interface. The morphologies of these IMCs are quite different for different solder compositions. As-reflowed, the growth rates of IMCs in the Sn-Zn based solder are higher than in the Sn-Ag-Cu and Sn-Pb solders. Different types of IMCs such as {gamma}-Cu{sub 5}Zn{sub 8}, {beta}-CuZn and a thin unknown Cu-Zn layer are formed in the Sn-Zn based solder but in the cases of Cu/Sn-Pb and Cu/Sn-Ag-Cu solder systems Cu{sub 6}Sn{sub 5} IMC layers are formed at the interface. Cu{sub 6}Sn{sub 5} and Cu{sub 3}Sn interfacial IMCs are formed in the early stages of 10 min reflow due to the limited supply of Sn from the Sn-Pb solder. The spalling of Cu-Sn IMCs is observed only in the Sn-Ag-Cu solder. The size of Zn platelets is increased with an increase of reflow time for the Cu/Sn-Zn solder system. In the case of the Sn-Zn-Bi solder, there is no significant increase in the Zn-rich phases with extended reflow time. Also, Bi offers significant effects on the wetting, the growth rate of IMCs as well as on the size and distribution of Zn-rich phases in the {beta}-Sn matrix. No Cu-Sn IMCs are found in the Sn-Zn based solder during 20 min reflow. The consumption of Cu by the solders are ranked as Sn-Zn-Bi > Sn-Ag-Cu > Sn-Zn > Sn-Pb. Despite the higher Cu-consumption rate, Bi-containing solder may be a promising candidate for a lead-free solder in modern electronic packaging taking into account its lower soldering temperature and material costs.

  8. High-spin states of the neutron-rich nucleus sup 1 sup 2 sup 5 Sb

    CERN Document Server

    Liu Zhong; Ma Yin Gjun; Sasaki, Y; Yamada, K; Oshima, H; Yokose, S; Ishizuka, M; Komatsubara, T; Furuno, K

    2002-01-01

    High spin states of sup 1 sup 2 sup 5 Sb have been investigated for the first time by means of in-beam gamma-ray spectroscopy techniques via the sup 1 sup 2 sup 4 Sn( sup 7 Li, alpha 2n) reaction at 32 MeV beam energy. Based on the measurements of gamma-gamma coincidence and gamma-ray anisotropies, a level scheme including 21 new gamma-transitions and 14 new excited levels was established up to 23/2 sup +. Three isomers at 1970, 2110 and 2471 keV levels have been identified and proposed as three-quasiparticle pi g sub 7 sub / sub 2 nu(h sub 1 sub 1 sub / sub 2 s sub 1 sub / sub 2), pi g sub 7 sub / sub 2 nu(h sub 1 sub 1 sub / sub 2 d sub 3 sub / sub 2) and pi g sub 7 sub / sub 2 nu(h sub 1 sub 1 sub / sub 2 sup 2) configurations, respectively. The level structure of sup 1 sup 2 sup 5 Sb is discussed in terms of particle-core coupling

  9. Effect of Pb doped on thermal stability and electrical transport properties of single crystalline β-Zn4Sb3

    Science.gov (United States)

    Deng, Shuping; Chen, Zhong; Li, Decong; Liu, Hongxia; Tang, Yu; Shen, Lanxian; Deng, Shukang

    2017-12-01

    In this study, we report the effect of Pb doping on both thermal stability and electrical transport properties of the single crystalline β-Zn4Sb3,prepared based on the initial stoichiometric ratios of Zn4-xSb3PbxSn3 (x = 0, 0.2, 0.4, 0.6 and 0.8). All samples possess a metallic luster surface and hardly defects and pores. The TG-DSC results show that the Pb doping samples exhibit an excellent thermal stability. Electrical transport properties of the samples were optimized by Pb doping. Among all samples exhibit p-type conduction with carrier concentrations varying from 4.88 × 1019 to 14.29 × 1019 cm-3, as carrier mobility changes from 31.1 to 66.4 cm2 V-1 s-1 at room temperature. With the increase of Pb initial content, Seebeck coefficient increases and electrical conductivity decreases. The sample with Pb initial content x = 0.6 exhibits an excellent electrical properties, and obtains maximum power factor of 1.69 × 10-3 W m-1 K-2 at 390 K.

  10. AgSbSe{sub 2} and AgSb(S,Se){sub 2} thin films for photovoltaic applications

    Energy Technology Data Exchange (ETDEWEB)

    Garza, J.G. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon (Mexico); Shaji, S. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon (Mexico); Facultad de Ingenieria Mecanica y Electrica, CIIDIT - Universidad Autonoma de Nuevo Leon, Apodaca, Nuevo Leon (Mexico); Rodriguez, A.C.; Das Roy, T.K. [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon (Mexico); Krishnan, B., E-mail: kbindu_k@yahoo.com [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, Nuevo Leon (Mexico); Facultad de Ingenieria Mecanica y Electrica, CIIDIT - Universidad Autonoma de Nuevo Leon, Apodaca, Nuevo Leon (Mexico)

    2011-10-01

    Silver antimony selenide (AgSbSe{sub 2}) thin films were prepared by heating sequentially deposited multilayers of antimony sulphide (Sb{sub 2}S{sub 3}), silver selenide (Ag{sub 2}Se), selenium (Se) and silver (Ag). Sb{sub 2}S{sub 3} thin film was prepared from a chemical bath containing SbCl{sub 3} and Na{sub 2}S{sub 2}O{sub 3}, Ag{sub 2}Se from a solution containing AgNO{sub 3} and Na{sub 2}SeSO{sub 3} and Se thin films from an acidified solution of Na{sub 2}SeSO{sub 3}, at room temperature on glass substrates. Ag thin film was deposited by thermal evaporation. The annealing temperature was 350 deg. C in vacuum (10{sup -3} Torr) for 1 h. X-ray diffraction analysis showed that the thin films formed were polycrystalline AgSbSe{sub 2} or AgSb(S,Se){sub 2} depending on selenium content in the precursor films. Morphology and elemental analysis of these films were done using scanning electron microscopy and energy dispersive X-ray spectroscopy. Optical band gap was evaluated from the UV-visible absorption spectra of these films. Electrical characterizations were done using Hall effect and photocurrent measurements. A photovoltaic structure: glass/ITO/CdS/AgSbSe{sub 2}/Al was formed, in which CdS was deposited by chemical bath deposition. J-V characteristics of this structure showed V{sub oc} = 435 mV and J{sub sc} = 0.08 mA/cm{sup 2} under illumination using a tungsten halogen lamp. Preparation of a photovoltaic structure using AgSbSe{sub 2} as an absorber material by a non-toxic selenization process is achieved.

  11. Preparation of Al–Sb semiconductor by swift heavy ion irradiation

    Indian Academy of Sciences (India)

    results in material modifications like structural changes, plastic deformation, or alteration at the phase composition. The observation of ion tracks in quartz and other insulators as well as the damage observed in semiconductors and metals indicate that a vivid motion of atoms must have taken place in a small cylinder along ...

  12. Contamination of soils with heavy metals and metalloids and its ecological hazard (analytic review)

    Science.gov (United States)

    Vodyanitskii, Yu. N.

    2013-07-01

    According to the present-day ecotoxicologic data, hazardous heavy metals/metalloids form the following sequence in the soil: Se > Tl > Sb > Cd > V > Hg > Ni > Cu > Cr > As > Ba. This sequence differs from the well-known series of the hazardous heavy elements, in which the danger of Pb and Zn is exaggerated, whereas that of V, Sb, and Ba, is underestimated. Tl also should be included in the list of hazardous elements in the soil. At present, the stress is made on the investigation of heavy metals/metalloids in agricultural soils rather than in urban soils, as the former produce contaminated products poisoning both animals and humans. The main sources of soil contamination with heavy metals are the following: aerial deposition from stationary and moving sources; hydrogenic contamination from the industrial sewage discharging into water bodies; sewage sediments; organic and mineral fertilizers and chemicals for plant protection, tailing dumps of ash, slag, ores, and sludge. In addition to the impact on plants and groundwater, heavy metals/metalloids exert a negative effect on the soil proper. Soil microorganisms appear to be very sensitive to the influence of heavy elements.

  13. Single-Particle States in $^{133}$Sn

    CERN Multimedia

    Huck, A

    2002-01-01

    % IS338 \\\\ \\\\ It is suggested to investigate the $\\beta^- $-decay of $^{133}$In and $^{134}$In in order to determine the single-particle states in $^{133}$Sn, which are so far unknown and needed for the shell-model description of the region close to $^{132}$Sn. Large hyper-pure Ge-detectors will be used for the $\\gamma$-ray spectroscopy. In the experiments with $^{134}$In, delayed neutrons in coincidence with $\\gamma$-rays from excited states in $^{133}$Sn provide the opportunity for a very selective detection of the states in question.

  14. SN 1006: a thousand-year perspective

    Science.gov (United States)

    Winkler, P. Frank

    2007-08-01

    We review some of the extensive historical observations of SN 1006, emphasizing estimates of its brightness at maximum. An estimate of Vmax ≈ -7.5 is consistent with what may be the most reasonable interpretation of these records and with an a posteriori calculation based on typical peak magnitudes for Type Ia supernovae together with the distance and extinction to SN 1006. We also give a brief overview of the discovery of the SN 1006 remnant in 1965, and contrast the earliest radio, optical, and X-ray observations of the remnant with recent ones, as reported in more detail by other papers in this JD09 review.

  15. Observation of Sb sub 2 O sub 3 nanocrystals in SiO sub 2 after Sb ion implantation

    CERN Document Server

    Ignatova, V A; Gijbels, R; Adams, F; Lebedev, O I; Landuyt, J V; Waetjen, U

    2002-01-01

    Antimony nanocrystals were formed in thin SiO sub 2 films using low-energy ion implantation of Sb followed by annealing. Using Fourier transform laser microprobe mass spectrometry (FT LMMS), we observed for the first time the presence of antimony oxide in the intermediate phase (as-implanted layer of Sb) by means of signals referring to the intact Sb sub 2 O sub 3 molecules. Only SbO sup + fragments, but no adduct ions of Sb sub 2 O sub 3 could be detected in annealed samples. The size and the distribution of the nanocrystals formed around the initial depth of implantation were studied in the as-implanted samples by high-resolution electron microscopy (HREM). The crystalline structure of these nanocrystals was also studied and the presence of antimony trioxide Sb sub 2 O sub 3 in the form of valentinite was proven. After the annealing step, the implanted material had spread into a wider band. The method introduced here, based on combining TEM (transmission electron microscopy) and FT LMMS results, offers the ...

  16. Optoelectronic Structure and Related Transport Properties of Ag2Sb2O6 and Cd2Sb2O7

    Science.gov (United States)

    Irfan, Muhammad; Hussain, Safdar; Khan, Saleem Ayaz; Goumri-Said, Souraya; Azam, Sikander

    2018-02-01

    Using the full-potential linearized augmented-plane wave method, the electronic structure and thermoelectric properties of Ag2Sb2O6 and Cd2Sb2O7 compounds have been explored. The modified Becke-Johnson potential was applied to treat the exchange-correlation energy term. The electronic band structures reveal that the valence-band maximum and conduction-band minimum occur at Γ point, indicating that Ag2Sb2O6 and Cd2Sb2O7 are direct energy bandgap semiconductors. Strong hybridization appeared between Ag (Cd)- s/ p and O- s/ p states. The optical properties, i.e., complex dielectric function, reflectivity, refractive index, and energy loss function, reveal high reflectivity in the ultraviolet energy range, indicating usefulness of these materials in shields from high-energy radiation. Combining transport theory and the outputs from the full-potential linearized augmented-plane wave calculations, the thermoelectric properties were analyzed as functions of temperature. Due to their high thermopower and narrow bandgap, Ag2Sb2O6 and Cd2Sb2O7 are suitable materials for application in optoelectronic and thermoelectric devices.

  17. Gel-combustion synthesis of CoSb2O6 and its reduction to powdery Sb2Co alloy

    Directory of Open Access Journals (Sweden)

    MAJA JOVIC

    2009-01-01

    Full Text Available Sb2Co alloy in powdery form was synthesized via reduction with gaseous hydrogen of the oxide CoSb2O6, obtained by the citrate gel-combustion technique. The precursor was an aqueous solution of antimony nitrate, cobalt nitrate and citric acid. The precursor solution with mole ratio Co(II/Sb(V of 1:2 was gelatinized by evaporation of water. The gel was heated in air up to the temperature of self-ignition. The product of gel combustion was a mixture of oxides and it had to be additionally thermally treated in order to be converted to pure CoSb2O6. The reduction of CoSb2O6 by gaseous hydrogen yielded powdery Sb2Co as the sole phase. The process of oxide reduction to alloy was controlled by thermogravimetry, while X-ray diffractometry was used to control the phase compositions of both the oxides and alloys.

  18. Ordered CoSn-type ternary phases in Co3Sn3-xGex

    DEFF Research Database (Denmark)

    Allred, Jared M.; Jia, Shuang; Bremholm, Martin

    2012-01-01

    CoSn is the prototype compound of the B35 structure, which has long been of interest due to its rarity and unusually low packing density. We report the synthesis and properties of the solid solution Co3Sn3-xGex for 0 ⩽ x ⩽ 2, in order to clarify the conditions necessary to stabilize such a phase....... By taking advantage of the chemical differences between the two crystallographically inequivalent Sn sites in the structure, we observe ordered ternary phases, nominally Co3SnGe2 and Co3Sn2Ge. The electron count and unit cell configuration remain unchanged from CoSn; these observations thus help to clarify...

  19. A study of self-assembled InSb quantum dots grown on GaSb

    CERN Document Server

    Alphandery, E

    2002-01-01

    In this thesis, we study the system of self-assembled InSb quantum dots grown on GaSb by metalorganic vapor phase epitaxy. The luminescence of the samples is first studied as a function of different growth parameters. In the series of high growth rate samples, a 'low energy peak' is observed at 0.72-0.74 eV for longer deposition times than 2 seconds and for growth temperatures of 460-500 degC. This peak is attributed to dots that are strongly confined in the growth direction. As the growth rate is halved, a new 'high energy peak' appears in the PL spectra at 0.755-0.79 eV that we assign to another family of big alloyed quantum dots. The luminescence of the high growth rate samples is then studied as a function of excitation power, temperature and magnetic field. When the excitation power is increased the quantum dot transition increases in energy by approx 7-11 meV and further transitions are observed from the wetting layer, bulk acceptor, bound (BE3) and free excitons. Magneto-PL is used to calculate the in-...

  20. Reactions in Electrodeposited Cu/Sn and Cu/Ni/Sn Nanoscale Multilayers for Interconnects

    Directory of Open Access Journals (Sweden)

    Pay Ying Chia

    2016-05-01

    Full Text Available Miniaturization of electronic devices has led to the development of 3D IC packages which require ultra-small-scale interconnections. Such small interconnects can be completely converted into Cu-Sn based intermetallic compounds (IMCs after reflow. In an effort to improve IMC based interconnects, an attempt is made to add Ni to Cu-Sn-based IMCs. Multilayer interconnects consisting of stacks of Cu/Sn/Cu/Sn/Cu or Cu/Ni/Sn/Ni/Sn/Cu/Ni/Sn/Ni/Cu with Ni = 35 nm, 70 nm, and 150 nm were electrodeposited sequentially using copper pyrophosphate, tin methanesulfonic, and nickel Watts baths, respectively. These multilayer interconnects were investigated under room temperature aging conditions and for solid-liquid reactions, where the samples were subjected to 250 °C reflow for 60 s and also 300 °C for 3600 s. The progress of the reaction in the multilayers was monitored by using X-ray Diffraction, Scanning Electron Microscope, and Energy dispersive X-ray Spectroscopy. FIB-milled samples were also prepared for investigation under room temperature aging conditions. Results show that by inserting a 70 nanometres thick Ni layer between copper and tin, premature reaction between Cu and Sn at room temperature can be avoided. During short reflow, the addition of Ni suppresses formation of Cu3Sn IMC. With increasing Ni thickness, Cu consumption is decreased and Ni starts acting as a barrier layer. On the other hand, during long reflow, two types of IMC were found in the Cu/Ni/Sn samples which are the (Cu,Ni6Sn5 and (Cu,Ni3Sn, respectively. Details of the reaction sequence and mechanisms are discussed.

  1. Effect of Sn Grain Orientation on the Cu6Sn5 Formation in a Sn-Based Solder Under Current Stressing

    Science.gov (United States)

    Lin, Chih-Fan; Lee, Shang-Hua; Chen, Chih-Ming

    2012-08-01

    A SnAgCu-based solder stripe between two Cu electrodes is current stressed with a density of 5 × 104 A/cm2 at 393 K (120 °C). After current stressing for 24 hours, electromigration induces the Cu dissolution from the cathode-side Cu electrode, leading to the Cu6Sn5 formation in the solder stripe. Very interestingly, the Cu6Sn5 phase is selectively formed within a specific Sn grain. Electron backscattering diffraction analysis indicates the crystallographic orientations of Sn grains play an important role in the selective Cu6Sn5 formation.

  2. Production of very neutron-deficient isotopes near {sup 100}Sn via reactions involving light-particle and cluster emission

    Energy Technology Data Exchange (ETDEWEB)

    La Commara, M.; Gomez del Campo, J.; D' Onofrio, A.; Gadea, A.; Glogowski, M.; Jarillo-Herrero, P.; Belcari, N.; Borcea, R.; De Angelis, G.; Fahlander, C.; Gorska, M.; Grawe, H.; Hellstroem, M.; Kirchner, R.; Rejmund, M.; Roca, V.; Roeckl, E.; Romano, M.; Rykaczewski, K.; Schmidt, K.; Terrasi, F

    2000-04-10

    The production of very neutron-deficient isotopes near {sup 100}Sn has been investigated by using on-line mass separation of evaporation residues produced by heavy-ion induced complete-fusion reactions. We measured the cross sections for {sup 99}Cd, {sup 100}In, {sup 101}Sn and {sup 102}In via {sup 58}Ni+{sup 58}Ni fusion reactions followed by cluster emission, and via {sup 58}Ni+{sup 50}Cr fusion reactions accompanied by evaporation of protons, neutrons or {alpha} particles. Both types of reactions yield similar cross sections for the production of exotic nuclei near {sup 100}Sn. The data are discussed in comparison with results obtained from statistical-model calculations.

  3. SN 2009ip and SN 2010mc as dual-shock Quark-Novae

    OpenAIRE

    Ouyed, Rachid; Koning, Nico; Leahy, Denis

    2013-01-01

    In recent years a number of double-humped supernovae have been discovered. This is a feature predicted by the dual-shock Quark-Nova model where a SN explosion is followed (a few days to a few weeks later) by a Quark-Nova explosion. SN 2009ip and SN 2010mc are the best observed examples of double-humped SNe. Here, we show that the dual-shock Quark-Nova model naturally explains their lightcurves including the late time emission, which we attribute to the interaction between the mixed SN and QN ...

  4. Polymer-SnO2 composite membranes

    DEFF Research Database (Denmark)

    Nørgaard, Casper Frydendal; Skou, Eivind Morten

    . This work utilizes the latter approach and makes use of particles of tin dioxide (SnO2). Polymer-SnO2 composite membranes were successfully prepared using an ion-exchange method. SnO2 was incorporated into membranes by ion-exchange in solutions of SnCl2 ∙ 2 H2O in methanol, followed by oxidation to SnO2...

  5. Conductivity studies in SnO–NaPO3 glasses

    Indian Academy of Sciences (India)

    Unknown

    to about 35 mol% SnO, above which activation barrier registers a moderate increase (Note: The percentages of. SnO in the glass composition indicate the initial quantity used to prepare the glass. Indeed, xSnO is in reality. 0⋅6 × SnIIO + 0⋅4 × SnIVO2). The region corresponding to rise in activation barrier is the regime of ...

  6. A new solid solution compound with the Sr{sub 21}Mn{sub 4}Sb{sub 18} structure type. Sr{sub 13}Eu{sub 8}Cd{sub 3}Mn{sub 1}Sb{sub 18}

    Energy Technology Data Exchange (ETDEWEB)

    Kunz Wille, Elizabeth L.; Cooley, Joya A.; Fettinger, James C.; Kazem, Nasrin; Kauzlarich, Susan M. [California Univ., Davis, CA (United States). Dept. of Chemistry

    2017-09-01

    The title compound with the nominal formula, Sr{sub 13}Eu{sub 8}Cd{sub 3}Mn{sub 1}Sb{sub 18}, was synthesized by Sn-flux. Structure refinement was based on single-crystal X-ray diffractometer data. Employing the exact composition, the formula is Sr{sub 13.23}Eu{sub 7.77}Cd{sub 3.12}Mn{sub 0.88}Sb{sub 18} for the solid solution Sr{sub 21-x}Eu{sub x}Cd{sub 4-y}Mn{sub y}Sb{sub 18}. This phase adopts the Sr{sub 21}Mn{sub 4}Sb{sub 18} type structure with site preferences for both Eu and Cd. The structure crystallizes in the monoclinic system in space group C2/m and Z=4: a=18.1522(11), b=17.3096(10), c=17.7691(10) Aa, β=91.9638(8) , 6632 F{sup 2} values, 216 variables, R1=0.0254 and wR2=0.0563. Site selectivity of the elements in this new compound will be discussed in relationship with the Sr{sub 21}Mn{sub 4}Sb{sub 18} type structure and other related structure types. Temperature dependent magnetic susceptibility data reveal Curie-Weiss paramagnetism with an experimental moment of 19.3 μ{sub B}/f.u. and a Weiss constant of 0.4 K. Magnetic ordering is seen at low temperatures, with a transition temperature of 3.5 K.

  7. Dirac neutrinos and SN 1987A

    Science.gov (United States)

    Turner, Michael S.

    1991-01-01

    Previous work has shown that the cooling of SN 1987A excludes a Dirac-neutrino mass greater than theta(20 keV) for nu(sub e), nu(sub mu), or nu(sub tau). The emission of wrong-helicity, Dirac neutrinos from SN 1987A, is re-examined. It is concluded that the effect of a Dirac neutrino on the cooling of SN 1987A has been underestimated due to neutrino degeneracy and additional emission processes. The limit that follows from the cooling of SN 1987A is believed to be greater (probably much greater) than 10 keV. This result is significant in light of the recent evidence for a 17 keV mass eigenstate that mixes with the electron neutrino.

  8. Transposon-mediated Generation of Cellular and Mouse Models of Splicing Mutations to Assess the Efficacy of snRNA-based Therapeutics

    Directory of Open Access Journals (Sweden)

    Elena Barbon

    2016-01-01

    Full Text Available Disease-causing splicing mutations can be rescued by variants of the U1 small nuclear RNA (U1snRNAs. However, the evaluation of the efficacy and safety of modified U1snRNAs as therapeutic tools is limited by the availability of cellular and animal models specific for a given mutation. Hence, we exploited the hyperactive Sleeping Beauty transposon system (SB100X to integrate human factor IX (hFIX minigenes into genomic DNA in vitro and in vivo. We generated stable HEK293 cell lines and C57BL/6 mice harboring splicing-competent hFIX minigenes either wild type (SChFIX-wt or mutated (SChFIXex5-2C. In both models the SChFIXex5-2C variant, found in patients affected by Hemophilia B, displayed an aberrant splicing pattern characterized by exon 5 skipping. This allowed us to test, for the first time in a genomic DNA context, the efficacy of the snRNA U1-fix9, delivered with an adeno-associated virus (AAV vector. With this approach, we showed rescue of the correct splicing pattern of hFIX mRNA, leading to hFIX protein expression. These data validate the SB100X as a versatile tool to quickly generate models of human genetic mutations, to study their effect in a stable DNA context and to assess mutation-targeted therapeutic strategies.

  9. Heavy quark masses

    Science.gov (United States)

    Testa, Massimo

    1990-01-01

    In the large quark mass limit, an argument which identifies the mass of the heavy-light pseudoscalar or scalar bound state with the renormalized mass of the heavy quark is given. The following equation is discussed: m(sub Q) = m(sub B), where m(sub Q) and m(sub B) are respectively the mass of the heavy quark and the mass of the pseudoscalar bound state.

  10. Assessment of atmospheric heavy metal deposition in the Tarkwa gold mining area of Ghana using epiphytic lichens

    Science.gov (United States)

    Boamponsem, L. K.; Adam, J. I.; Dampare, S. B.; Nyarko, B. J. B.; Essumang, D. K.

    2010-05-01

    In situ lichens ( Parmelia sulcata) have been used to assess atmospheric heavy metal deposition in the Tarkwa gold mining area of Ghana. Total heavy metal concentrations obtained by instrumental neutron activation analysis (INAA) were processed by positive matrix factorization (PMF), principal component (PCA) and cluster (CA) analyses. The pollution index factor (PIF) and pollution load index (PLI) criteria revealed elevated levels of Sb, Mn, Cu, V, Al, Co, Hg, Cd and As in excess of the background values. The PCA and CA classified the examined elements into anthropogenic and natural sources, and PMF resolved three primary sources/factors: agricultural activities and other non-point anthropogenic origins, natural soil dust, and gold mining activities. Gold mining activities, which are characterized by dominant species of Sb, Th, As, Hg, Cd and Co, and significant contributions of Cu, Al, Mn and V, are the main contributors of heavy metals in the atmosphere of the study area.

  11. Crystal structures of the new ternary stannides La{sub 3}Mg{sub 4−x}Sn{sub 2+x} and LaMg{sub 3−x}Sn{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Solokha, P., E-mail: pavlo.solokha@unige.it [Università degli Studi di Genova, Dipartimento di Chimica e Chimica Industriale, via Dodecaneso 31, 16146 Genova (Italy); De Negri, S.; Minetti, R. [Università degli Studi di Genova, Dipartimento di Chimica e Chimica Industriale, via Dodecaneso 31, 16146 Genova (Italy); Proserpio, D.M. [Università degli Studi di Milano, Dipartimento di Chimica, Via Golgi 19, 20133 Milano (Italy); Samara Center for Theoretical Materials Science (SCTMS), Samara State University, Samara 443011 (Russian Federation); Saccone, A. [Università degli Studi di Genova, Dipartimento di Chimica e Chimica Industriale, via Dodecaneso 31, 16146 Genova (Italy)

    2016-01-15

    Synthesis and structural characterization of the two new lanthanum–magnesium–stannides La{sub 3}Mg{sub 4−x}Sn{sub 2+x} (0.12≤x≤0.40) and LaMg{sub 3−x}Sn{sub 2} (0.33≤x≤0.78) are reported. The crystal structures of these intermetallics were determined by single crystal X-ray diffraction analysis and confirmed by Rietveld refinement of powder X-ray diffraction patterns of the corresponding samples. The La{sub 3}Mg{sub 4−x}Sn{sub 2+x} phase crystallizes in the hexagonal Zr{sub 3}Cu{sub 4}Si{sub 2} structure type (P6¯2m, hP9, Z=3, x=0.12(1), a=7.7974(7), c=4.8384(4) Å), which represents an ordered derivative of the hP9-ZrNiAl prototype, ubiquitous among equiatomic intermetallics. The LaMg{sub 3–x}Sn{sub 2} phase is the second representative of the trigonal LaMg{sub 3−x}Ge{sub 2} type, which is a superstructure of the LaLi{sub 3}Sb{sub 2} structure type (P3¯1c, hP34-0.12, Z=6, x=0.35(1), a=8.3222(9), c=14.9546(16) Å). The scheme describing the symmetry reduction/coloring with respect to the parent type is reported here with the purpose to discuss the LaMg{sub 3−x}Sn{sub 2} off-stoichiometry from the geometrical point of view. Structural relationships between the La–Mg–Sn ternary phases, including the already known equiatomic LaMgSn compound (oP12-TiNiSi), are presented in the framework of the AlB{sub 2}-related compounds family and discussed with the aid of group-subgroup relations in the Bärnighausen formalism. - Graphical abstract: Crystal structure of LaMg{sub 3−x}Sn{sub 2} viewed along the (001) direction together with the puckered layer of Mg and Sn atoms hosting Mg2, Mg3 and vacancy □. - Highlights: • Crystal structures of the new La{sub 3}Mg{sub 4−x}Sn{sub 2+x} and LaMg{sub 3−x}Sn{sub 2} phases were determined. • The off-stoichiometry of LaMg{sub 3−x}Sn{sub 2} was discussed from geometrical point of view. • Structural relations between the known La–Mg–Sn phases were established. • The studied compounds are

  12. Sn(II), −Sm(II)

    African Journals Online (AJOL)

    Preferred Customer

    Sm(NTA)]⋅H2O (3), and. [Sm(NTA)(H2O)2]⋅H2O (4) were obtained during the reactions of metal salts (VCl3, SnCl2⋅2H2O, SnCl4,. Sm(NO3)2⋅6H2O and SmCl3⋅6H2O) with nitrilotriacetic acid, H3NTA. The infrared and 1H-NMR spectra of the.

  13. Production of heavy water

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, Larry S.; Brown, Sam W.; Phillips, Michael R.

    2017-06-06

    Disclosed are methods and apparatuses for producing heavy water. In one embodiment, a catalyst is treated with high purity air or a mixture of gaseous nitrogen and oxygen with gaseous deuterium all together flowing over the catalyst to produce the heavy water. In an alternate embodiment, the deuterium is combusted to form the heavy water. In an alternate embodiment, gaseous deuterium and gaseous oxygen is flowed into a fuel cell to produce the heavy water. In various embodiments, the deuterium may be produced by a thermal decomposition and distillation process that involves heating solid lithium deuteride to form liquid lithium deuteride and then extracting the gaseous deuterium from the liquid lithium deuteride.

  14. Experimental investigation of the degassing behavior of Hg via proxy heavy metals in natural and synthetic silicate melts

    Science.gov (United States)

    Johnson, A. D.; Canil, D.

    2009-12-01

    The degassing behavior of Bi, Tl, Au, Cd and Pb from silicate liquids have been investigated at 0.1 MPa. These metals were chosen on the basis that they may be used as a proxy for Hg. Natural basalt, dacite, and synthetic rhyolite (Ab-Or-Qz minimum eutectic) were doped with a heavy metal cocktail (Bi, Pb, Tl, Au, Re, Sb, Sn, In, Cd, Mo, As, Cu) and diffusion experiments were conducted in air at 0.1 MPa between 1200 - 1450 °C in open Pt capsules. Trace element concentration gradients for Bi, Tl, Au, Cd and Pb were measured normal to the polished melt(glass)/gas interface by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) after the experiment. Diffusion coefficients (Dx) were extracted for elements using a semi-infinite one-dimensional diffusion model. The effects of ligands on diffusivity were measured by adding Cl or S to experimental runs. Results show Au and Tl (which bracket Hg in the periodic table) are the most volatile in dacite at 1260°C (logDAu = -10.66 ± 0.20 m2/s and logDTl = -11.03 ± 0.15 m2/s ) followed by Cd, Pb and Bi (logDCd = -11.58 ± 0.07 m2/s, logDPb = -11.77 ± 0.2 m2/s, logDBi = -12.11 ± 0.2 m2/s;). The effect of starting composition on metal diffusion shows the diffusivity of Tl at 1260°C decreases from logDTl = -10.84 ± 0.22 m2/s in basalt to logDTl = -11.03 ± 0.15 m2/s and logDTl = -11.60 ± 0.20 m2/s in dacite and synthetic Ab-Or-Qz respectively. Decreasing diffusivity would be expected with increasing silica content that inhibits diffusion. We apply our diffusivities in a 1-D bubble growth model to observe differences in metal ratios in gas bubbles that would form in volcanic plumes. In this way, we see the changing heavy metal ratios in the gas phase may be useful in eruption prediction. This work may also help better constrain the behavior/mobility of Hg (using these metals as a proxy) in nature and its loading effect from volcanoes on the atmosphere and biosphere.

  15. Biomarkers of oxidative stress in rat for assessing toxicological effects of heavy metal pollution in river water.

    Science.gov (United States)

    Reddy, Utkarsh A; Prabhakar, P V; Rao, G Sankara; Rao, Pasham Rajasekhar; Sandeep, K; Rahman, M F; Kumari, S Indu; Grover, Paramjit; Khan, Haseeb A; Mahboob, M

    2015-09-01

    Increasing use of heavy metals in various fields, their environmental persistency, and poor regulatory efforts have significantly increased their fraction in river water. We studied the effect of Musi river water pollution on oxidative stress biomarkers and histopathology in rat after 28 days repeated oral treatment. River water analysis showed the presence of Zn and Pb at mg/l concentration and Ag, As, Ba, Cd, Co, Cr, Cu, Mn, Mo, Ni, Sn, and Sb at μg/l concentration. River water treatment resulted in a dose-dependent accumulation of metals in rat organs, being more in liver followed by kidney and brain. Metal content in both control and low-dose group rat organs was below limit of detection. However, metal bioaccumulation in high- and medium-dose group organs as follows: liver-Zn (21.4 & 14.5 μg/g), Cu (8.3 & 3.6 μg/g), and Pb (8.2 & 0.4 μg/g); kidney-Zn (16.2 & 7.9 μg/g), Cu (3.5 & 1.4 μg/g), Mn (2.9 & 0.5 μg/g), and Pb (2.6 & 0.5 μg/g); and brain-Zn (2.4 & 1.1 μg/g), and Ni (1 & 0.3 μg/g). These metals were present at high concentrations in respective organs than other metals. The increased heavy metal concentration in treated rat resulted significant increase in superoxide dismutase, glutathione peroxidase, glutathione reductase, glutathione S transferase enzymes activity, and lipid peroxidation in a dose-dependent manner. However, glutathione content and catalase activity were significantly decreased in treated rat organs. Histopathological examination also confirmed morphological changes in rat organs due to polluted river water treatment. In conclusion, the findings of this study clearly indicate the oxidative stress condition in rat organs due to repeated oral treatment of polluted Musi river water.

  16. Distribution and health risk assessment to heavy metals near smelting and mining areas of Hezhang, China.

    Science.gov (United States)

    Briki, Meryem; Zhu, Yi; Gao, Yang; Shao, Mengmeng; Ding, Huaijian; Ji, Hongbing

    2017-08-19

    Mining and smelting areas in Hezhang have generated a large amount of heavy metals into the environment. For that cause, an evaluative study on human exposure to heavy metals including Co, Ni, Cu, Zn, Cr, As, Cd, Pb, Sb, Bi, Be, and Hg in hair and urine was conducted for their concentrations and correlations. Daily exposure and non-carcinogenic and carcinogenic risk were estimated. Sixty-eight scalp hair and 66 urine samples were taken from participants of different ages (6-17, 18-40, 41-60, and ≥ 65 years) living in the vicinity of an agricultural soil near mine and smelting areas. The results compared to the earlier studies showed an elevated concentration of Pb, Be, Bi, Co, Cr, Ni, Sb, and Zn in hair and urine. These heavy metals were more elevated in mining than in smelting. Considering gender differences, females were likely to be more affected than male. By investigating age differences in this area, high heavy metal concentrations in male's hair and urine existed in age of 18-40 and ≥ 66, respectively. However, females did not present homogeneous age distribution. Hair and urine showed a different distribution of heavy metals in different age and gender. In some cases, significant correlation was found between heavy metals in hair and urine (P > 0.05 and P > 0.01) in mining area. The estimated average daily intake of heavy metals in vegetables showed a great contribution compared to the soil and water. Non-carcinogenic and carcinogenic risk values of total pathways in mining and smelting areas were higher than 1 and exceeded the acceptable levels. Thus, the obtained data might be useful for further studies. They can serve as a basis of comparison and assessing the effect of simultaneous exposure from heavy metals in mining and smelting areas, and potential health risks from exposure to heavy metals in vegetables need more consideration.

  17. Electrochemical characterization of SnO{sub 2} electrodes doped with Ru and Pt

    Energy Technology Data Exchange (ETDEWEB)

    Berenguer, R. [Departamento de Quimica Fisica e Instituto Universitario de Materiales, Universidad de Alicante, Apartado 99, E-03080 Alicante (Spain); Quijada, C. [Departamento de Ingenieria Textil y Papelera, Universidad Politecnica de Valencia, 1, E-03801 Alcoy (Alicante) (Spain); Morallon, E. [Departamento de Quimica Fisica e Instituto Universitario de Materiales, Universidad de Alicante, Apartado 99, E-03080 Alicante (Spain)], E-mail: morallon@ua.es

    2009-09-01

    Antimony-platinum doped tin dioxide electrodes supported on titanium have been prepared by thermal decomposition. The effect of the progressive replacement of Sb with Ru (x = 0.00; 3.25; 6.50; 13.00 at.%) on their electrochemical response in acid medium has been analysed by cyclic voltammetry. The morphology of the coatings was observed by scanning electron microscopy. Ti/SnO{sub 2}-Sb-Pt electrodes without Ru presented a cracked-mud structure, typical of oxide electrodes prepared by thermal decomposition. The introduction of Ru in the oxide layer modified the coating morphology. The roughness increased and passed through a maximum with the increase of Ru content. A relation between the surface morphology, the roughness factor, voltammetric charge and the electrochemical activity has been established. The mechanism and electrocatalytic activity towards the oxygen evolution reaction has been studied from Tafel measurements. The progressive introduction of Ru in the electrodes increased their electrocatalytic activity for the oxygen evolution reaction with a change on the mechanism from non-active to active electrodes. The electrocatalytic activity mainly depends on electronic factors.

  18. Nanostructuring of Undoped ZnSb by Cryo-Milling

    Science.gov (United States)

    Song, X.; Valset, K.; Graff, J. S.; Thøgersen, A.; Gunnæs, A. E.; Luxsacumar, S.; Løvvik, O. M.; Snyder, G. J.; Finstad, T. G.

    2015-08-01

    We report the preparation of nanosized ZnSb powder by cryo-milling. The effect of cryo-milling then hot-pressing of undoped ZnSb was investigated and compared with that of room temperature ball-milling and hot-pressing under different temperature conditions. ZnSb is a semiconductor with favorable thermoelectric properties when doped. We used undoped ZnSb to study the effect of nanostructuring on lattice thermal conductivity, and with little contribution at room temperature from electronic thermal conductivity. Grain growth was observed to occur during hot-pressing, as observed by transmission electron microscopy and x-ray diffraction. The thermal conductivity was lower for cryo-milled samples than for room-temperature ball-milled samples. The thermal conductivity also depended on hot-pressing conditions. The thermal conductivity could be varied by a factor of two by adjusting the process conditions and could be less than a third that of single-crystal ZnSb.

  19. (Ga,Fe)Sb: A p-type ferromagnetic semiconductor

    Energy Technology Data Exchange (ETDEWEB)

    Tu, Nguyen Thanh; Anh, Le Duc; Tanaka, Masaaki [Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan); Hai, Pham Nam [Department of Electrical Engineering and Information Systems, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656 (Japan); Department of Physical Electronics, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo 152-0033 (Japan)

    2014-09-29

    A p-type ferromagnetic semiconductor (Ga{sub 1−x},Fe{sub x})Sb (x = 3.9%–13.7%) has been grown by low-temperature molecular beam epitaxy (MBE) on GaAs(001) substrates. Reflection high energy electron diffraction patterns during the MBE growth and X-ray diffraction spectra indicate that (Ga,Fe)Sb layers have the zinc-blende crystal structure without any other crystallographic phase of precipitates. Magnetic circular dichroism (MCD) spectroscopy characterizations indicate that (Ga,Fe)Sb has the zinc-blende band structure with spin-splitting induced by s,p-d exchange interactions. The magnetic field dependence of the MCD intensity and anomalous Hall resistance of (Ga,Fe)Sb show clear hysteresis, demonstrating the presence of ferromagnetic order. The Curie temperature (T{sub C}) increases with increasing x and reaches 140 K at x = 13.7%. The crystal structure analyses, magneto-transport, and magneto-optical properties indicate that (Ga,Fe)Sb is an intrinsic ferromagnetic semiconductor.

  20. Surface passivation of backside-illuminated InSb FPAs

    Science.gov (United States)

    Wei, Peng; Zheng, Kelin; Wang, Liwen; Geng, Dongfeng; Su, Xianjun

    2016-10-01

    A method of passivation of etch-thinned bulk InSb by anodic oxide grown by wet anodization and vacuum deposition of SiNx layers have been investigated Thinned bulk n-type InSb with (111) orientation forms distinctively two types of interfaces on the indium and antimony faces, respectively. The junctions are diffused on the indium face. The paper presents the process and characterization for surface passivation of the backside illuminated Sb face that absorbs the photons. The surface passivation and the interfaces are characterized with Metal-Insulator-Semiconductor (MIS) devices. The effect of anodic oxide/SiNx passivation was compared to SiNx passivation. The electrical features observed in the C-V curves of MIS structures indicate that anodic oxide grown by wet anodization has the better effect on reducing the surface states and surface recombination velocity. The low-frequency-like response in the inversion region of the C-V curves was explained in view of the oxidation states of In and Sb. Finally, by growing the 30nm anodic oxide and depositing 400nm SiNx on diode structure of InSb, the performance of FPA in this case was compared with the SiNx only method. The results showed the performance of device is better than for the SiNx only method.

  1. Characterization of midwave infrared InSb avalanche photodiode

    Energy Technology Data Exchange (ETDEWEB)

    Abautret, J., E-mail: johan.abautret@ies.univ-montp2.fr; Evirgen, A. [Université Montpellier, IES, UMR 5214, F-34095 Montpellier (France); CNRS, IES, UMR 5214, F-34095 Montpellier (France); SOFRADIR, BP 21, 38113 Veurey-Voroize (France); Perez, J. P.; Christol, P. [Université Montpellier, IES, UMR 5214, F-34095 Montpellier (France); CNRS, IES, UMR 5214, F-34095 Montpellier (France); Rothman, J. [CEA-LETI, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France); Cordat, A. [SOFRADIR, BP 21, 38113 Veurey-Voroize (France)

    2015-06-28

    This paper focuses on the InSb material potential for the elaboration of Avalanche Photodiodes (APD) for high performance infrared imaging applications, both in passive or active mode. The first InSb electron-APD structure was grown by molecular beam epitaxy, processed and electrically characterized. The device performances are at the state of the art for the InSb epi-diode technology, with a dark current density J(−50 mV) = 32 nA/cm{sup 2} at 77 K. Then, a pure electron injection was performed, and an avalanche gain, increasing exponentially, was observed with a gain value near 3 at −4 V at 77 K. The Okuto–Crowell model was used to determine the electron ionization coefficient α(E) in InSb, and the InSb gain behavior is compared with the one of InAs and MCT APDs.

  2. Antimony segregation in the oxidation of AlAsSb interlayers

    OpenAIRE

    Andrews, A M; van Horn, K L; Mates, T; Speck, J S

    2003-01-01

    The lateral wet oxidation of strained AlAsSb was studied. AlAs0.80Sb0.20 interlayers were grown on a GaAs substrate and capped with a lattice-matched In0.25Ga0.75As layer. The AlAsSb was oxidized between 350 and 450 degreesC. Oxidation temperatures >400 degreesC resulted in poor surface morphology and delamination. Oxidation of thicker AlAsSb interlayers (h approximate to 2000 Angstrom) resulted in metallic Sb layers forming between the AlOx and the semiconductor interfaces. The remaining Sb ...

  3. Effects of the copper content on the structural and electrical properties of Cu{sub 2}ZnSnSe{sub 4} bulks

    Energy Technology Data Exchange (ETDEWEB)

    Tsega, Moges, E-mail: mogestsega@yahoo.com [Department of Physics, University of the Free State (Qwaqwa Campus), Private Bag X13, Phuthaditjhaba 9866 (South Africa); Department of Physics, Bahir Dar University (Ethiopia); Dejene, F.B.; Koao, L.F. [Department of Physics, University of the Free State (Qwaqwa Campus), Private Bag X13, Phuthaditjhaba 9866 (South Africa)

    2016-01-01

    We have investigated the concept of defect in Cu{sub x}ZnSnSe{sub 4} (x=1.6–2.0) and Cu{sub y}(Zn{sub 0.9}Sn{sub 1.1})Se{sub 4} (y= 1.6–2.0) bulks prepared by liquid-phase sintering at 600 °C for 2 h with soluble sintering aids of Sb{sub 2}S{sub 3} and Te. All samples were found to exhibit p-type semiconductor for Cu{sub x}ZnSnSe{sub 4}, while n-type of behavior obtained at y= 1.8–2.0 for Cu{sub y}(Zn{sub 0.9}Sn{sub 1.1})Se{sub 4} pellets. The Cu vacancy acts as an acceptor point defect to form the p-type semiconductor, and Sn{sup 4+} acts as a donor to form the n-type behavior for the Sn-rich CZTSe. SEM images of pellets show dense surface morphology, and increase in grain size upon Cu inclusion. The largely increased Hall mobility and the slightly changed carrier concentration for Cu{sub y}(Zn{sub 0.9}Sn{sub 1.1})Se{sub 4} with increasing the Cu content is related to the types of its defects. At y=2.0 with carrier concentration of 4.88×10{sup 17} cm{sup −3} showed the highest mobility of around 58 cm{sup 2}/V s. Based upon the proposed point defects, the CZTSe property can be consistently explained.

  4. Heavy Metal Contamination in Soil and Brown Rice and Human Health Risk Assessment near Three Mining Areas in Central China

    Directory of Open Access Journals (Sweden)

    Yu Fan

    2017-01-01

    Full Text Available Background. Metal mining and waste discharge lead to regional heavy metal contamination and attract major concern because of the potential risk to local residents. Methods. This research was conducted to determine lead (Pb, cadmium (Cd, arsenic (As, manganese (Mn, and antimony (Sb concentrations in soil and brown rice samples from three heavy metal mining areas in Hunan Province, central China, and to assess the potential health risks to local inhabitants. Results. Local soil contamination was observed, with mean concentrations of Cd, Pb, Sb, and As of 0.472, 193.133, 36.793, and 89.029 mg/kg, respectively. Mean concentrations of Cd, Pb, Sb, Mn, and As in brown rice were 0.103, 0.131, 5.175, 6.007, and 0.524 mg/kg, respectively. Daily intakes of Cd, As, Sb, Pb, and Mn through brown rice consumption were estimated to be 0.011, 0.0002, 0.004, 0.0001, and 0.0003 mg/(kg/day, respectively. The combined hazard index for the five heavy metals was 22.5917, and the total cancer risk was 0.1773. Cd contributed most significantly to cancer risk, accounting for approximately 99.77% of this risk. Conclusions. The results show that potential noncarcinogenic and carcinogenic health risks exist for local inhabitants and that regular monitoring of pollution to protect human health is urgently required.

  5. Neutron capture cross section measurements of 120Sn, 122Sn and 124Sn with the array of Ge spectrometer at the J-PARC/MLF/ANNRI

    Directory of Open Access Journals (Sweden)

    Kimura Atsushi

    2017-01-01

    Full Text Available Preliminary neutron capture cross section of 120Sn, 122Sn and 124Sn were obtained in the energy range from 20 meV to 4 keV with the array of germanium detectors in ANNRI at MLF,J-PARC. The results of 120Sn, 122Sn and 124Sn were obtained by normalizing the relative cross sections to the data in JENDL-4.0 at the largest 426.7-, 107.0- and 62.05-eV resonances, respectively. The 67.32- and 150-eV resonances for 120Sn and the 579- and 950-eV resonances for 124Sn which are listed in JENDL-4.0 and/or ENDF/B VII.1 were not observed.

  6. Improved structural and electrical properties in native Sb2Te3/GexSb2Te3+x van der Waals superlattices due to intermixing mitigation

    Directory of Open Access Journals (Sweden)

    Stefano Cecchi

    2017-02-01

    Full Text Available Superlattices made of Sb2Te3/GeTe phase change materials have demonstrated outstanding performance with respect to GeSbTe alloys in memory applications. Recently, epitaxial Sb2Te3/GeTe superlattices were found to feature GexSb2Te3+x blocks as a result of intermixing between constituting layers. Here we present the epitaxy and characterization of Sb2Te3/GexSb2Te3+x van der Waals superlattices, where GexSb2Te3+x was intentionally fabricated. X-ray diffraction, Raman spectroscopy, scanning transmission electron microscopy, and lateral electrical transport data are reported. The intrinsic 2D nature of both sublayers is found to mitigate the intermixing in the structures, significantly improving the interface sharpness and ultimately the superlattice structural and electrical properties.

  7. Influence of GaAsSb structural properties on the optical properties of InAs/GaAsSb quantum dots

    Science.gov (United States)

    Zhang, Zewen; Huang, Yidan; Reece, Peter J.; Bremner, Stephen P.

    2017-10-01

    The optical properties of InAs quantum dots with GaAsSb buffer, capping and cladding layers of different alloy compositions are studied by photoluminescence techniques. Fully strained GaAsSb layers show that the inclusion of a buffer layer gives a blue-shift to quantum dot emission, while for quantum dots capped with GaAsSb a clear red-shift is seen. Power-dependent photoluminescence suggests a transition from type-I to type-II can be achieved by GaAsSb at Sb composition between 11-13%, while the transition for the GaAsSb cladding layer occurs at around 11%. At low Sb composition, good crystal quality and energy barrier are detected by temperature-dependent photoluminescence, while high-level dislocation and defects exist under high antimony content, as evidenced by X-Ray Diffraction and Transmission Electron Microscopy.

  8. Effects upon metabolic pathways and energy production by Sb(III and As(III/Sb(III-oxidase gene aioA in Agrobacterium tumefaciens GW4.

    Directory of Open Access Journals (Sweden)

    Jingxin Li

    Full Text Available Agrobacterium tumefaciens GW4 is a heterotrophic arsenite [As(III]/antimonite [Sb(III]-oxidizing strain. The As(III oxidase AioAB is responsible for As(III oxidation in the periplasm and it is also involved in Sb(III oxidation in Agrobacterium tumefaciens 5A. In addition, Sb(III oxidase AnoA and cellular H2O2 are also responsible for Sb(III oxidation in strain GW4. However, the deletion of aioA increased the Sb(III oxidation efficiency in strain GW4. In the present study, we found that the cell mobility to Sb(III, ATP and NADH contents and heat release were also increased by Sb(III and more significantly in the aioA mutant. Proteomics and transcriptional analyses showed that proteins/genes involved in Sb(III oxidation and resistance, stress responses, carbon metabolism, cell mobility, phosphonate and phosphinate metabolism, and amino acid and nucleotide metabolism were induced by Sb(III and were more significantly induced in the aioA mutant. The results suggested that Sb(III oxidation may produce energy. In addition, without periplasmic AioAB, more Sb(III would enter bacterial cells, however, the cytoplasmic AnoA and the oxidative stress response proteins were significantly up-regulated, which may contribute to the increased Sb(III oxidation efficiency. Moreover, the carbon metabolism was also activated to generate more energy against Sb(III stress. The generated energy may be used in Sb transportation, DNA repair, amino acid synthesis, and cell mobility, and may be released in the form of heat.

  9. Effects upon metabolic pathways and energy production by Sb(III) and As(III)/Sb(III)-oxidase gene aioA in Agrobacterium tumefaciens GW4.

    Science.gov (United States)

    Li, Jingxin; Yang, Birong; Shi, Manman; Yuan, Kai; Guo, Wei; Li, Mingshun; Wang, Gejiao

    2017-01-01

    Agrobacterium tumefaciens GW4 is a heterotrophic arsenite [As(III)]/antimonite [Sb(III)]-oxidizing strain. The As(III) oxidase AioAB is responsible for As(III) oxidation in the periplasm and it is also involved in Sb(III) oxidation in Agrobacterium tumefaciens 5A. In addition, Sb(III) oxidase AnoA and cellular H2O2 are also responsible for Sb(III) oxidation in strain GW4. However, the deletion of aioA increased the Sb(III) oxidation efficiency in strain GW4. In the present study, we found that the cell mobility to Sb(III), ATP and NADH contents and heat release were also increased by Sb(III) and more significantly in the aioA mutant. Proteomics and transcriptional analyses showed that proteins/genes involved in Sb(III) oxidation and resistance, stress responses, carbon metabolism, cell mobility, phosphonate and phosphinate metabolism, and amino acid and nucleotide metabolism were induced by Sb(III) and were more significantly induced in the aioA mutant. The results suggested that Sb(III) oxidation may produce energy. In addition, without periplasmic AioAB, more Sb(III) would enter bacterial cells, however, the cytoplasmic AnoA and the oxidative stress response proteins were significantly up-regulated, which may contribute to the increased Sb(III) oxidation efficiency. Moreover, the carbon metabolism was also activated to generate more energy against Sb(III) stress. The generated energy may be used in Sb transportation, DNA repair, amino acid synthesis, and cell mobility, and may be released in the form of heat.

  10. Combined effects of antimony and sodium diethyldithiocarbamate on soil microbial activity and speciation change of heavy metals. Implications for contaminated lands hazardous material pollution in nonferrous metal mining areas.

    Science.gov (United States)

    Zhu, Xiaozhe; Yao, Jun; Wang, Fei; Yuan, Zhimin; Liu, Jianli; Jordan, Gyozo; Knudsen, Tatjana Šolević; Avdalović, Jelena

    2018-05-05

    The combined effects of antimony (Sb) and sodium diethyldithiocarbamate (DDTC), a common organic flotation reagent, on soil microbial activity and speciation changes of heavy metals were investigated for the first time. The results showed that the exchangeable fraction of Sb was transformed to a stable residual fraction during the incubation period, and the addition of DDTC promoted the transformation compared with single Sb pollution, probably because DDTC can react with heavy metals to form a complex. In addition, the presence of DDTC and Sb inhibited the soil microbial activity to varying degrees. The growth rate constant k of different interaction systems was in the following order on the 28th day: control group ≥ single DDTC pollution > combined pollution > single Sb pollution. A correlation analysis showed that the concentration of exchangeable Sb was the primary factor that affected the toxic reaction under combined pollution conditions, and it significantly affected the characteristics of the soil microorganisms. All the observations provide useful information for a better understanding of the toxic effects and potential risks of combined Sb and DDTC pollution in antimony mining areas. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Cluster radioactivity leading to doubly magic 100Sn and 132Sn ...

    Indian Academy of Sciences (India)

    Cluster radioactivity leading to doubly magic 100Sn and 132Sn daughters. K P SANTHOSH. School of Pure and Applied Physics, Kannur University, Payyanur Campus,. Payyanur 670 327, India. E-mail: drkpsanthosh@gmail.com. MS received 1 June 2010; revised 13 August 2010; accepted 8 September 2010. Abstract.

  12. Formation of SnO2 Nanowires Using Thermal Evaporation of SnO.

    Science.gov (United States)

    Lin, Yu-Yun; Lin, Che-Yu; Chen, Ching-Yi; Li, Yuan-Yao

    2015-12-01

    SnO2 nanowires (NWs) were grown on a catalyst-coated silicon wafer via the thermal evaporation of SnO powder at 20-30 mTorr. Three types of catalyst, namely Fe, Pt, and Au, were used for the synthesis of the SnO2 NWs. The results show that Pt and Au can be used for the formation of SnO2 NWs. Depending on the experimental conditions, the diameter and length of the SnO2 NWs obtained with Au catalyst are in the ranges of 20-65 nm and a few hundred nanometers to a few micrometers, respectively. The size of the Au nanocatalyst greatly affects the diameter of the SnO2 NWs. With increasing particle size of the Au catalyst, the diameter of the SnO2 NWs increased. In addition, the results show that the synthesis of SnO2 NWs can be conducted at 500 degrees C, which is compatible with low-temperature processes.

  13. Optical spectroscopy of complex open-4d-shell ions Sn7+-Sn10+

    NARCIS (Netherlands)

    Torretti, F.; Windberger, A.; Ryabtsev, A.; Dobrodey, S.; Bekker, H.; Ubachs, W.; Hoekstra, R.; Kahl, E. V.; Berengut, J. C.; Lopez-Urrutia, J. R. Crespo; Versolato, O. O.

    2017-01-01

    We analyze the complex level structure of ions with many-valence-electron open-[Kr] 4d(m) subshells (m = 7-4) with ab initio calculations based on configuration-interaction many-body perturbation theory (CI+MBPT). Charge-state-resolved optical and extreme ultraviolet (EUV) spectra of Sn7+-Sn10+ ions

  14. Optical spectroscopy of complex open 4d-shell ions Sn7+ - Sn10+

    NARCIS (Netherlands)

    Torretti, F.; Windberger, R.A.W.; Ryabtsev, A.; Dobrodey, S.; Bekker, H.; Ubachs, W.; Hoekstra, R.; Kahl, E. V.; Berengut, Julian C.; Crespo López-Urrutia, J. R.; Versolato, O.

    2017-01-01

    We analyze the complex level structure of ions with many-valence-electron open-[Kr] 4dm subshells (m=7–4) with ab initio calculations based on configuration-interaction many-body perturbation theory (CI+MBPT). Charge-state-resolved optical and extreme ultraviolet (EUV) spectra of Sn7+–Sn10+ ions

  15. Hyperfine field distributions in disordered Mn2CoSn and Mn2NiSn ...

    Indian Academy of Sciences (India)

    Unknown

    Mössbauer studies using Sn-119 were carried out to investigate the hyperfine fields present at the Sn site in these alloys. The hyperfine field distribution in these alloys as well as X-ray studies point to the chemical disorder present in both alloys. Co-existence of a paramagnetic portion along with the magnetic hyperfine part.

  16. Structure of liquid GaSb under pressure

    CERN Document Server

    Hattori, T; Takasugi, Y; Mori, T; Tsuji, K

    2002-01-01

    The structure of liquid GaSb has been investigated up to 10.1 GPa by means of energy-dispersive x-ray diffraction using a synchrotron radiation source and a multi-anvil apparatus. With increasing pressure up to about 5 GPa, the second and third peaks in the pair distribution functions, g(r), shift remarkably toward smaller r-values, while the first peak shifts toward larger r-values. This shows that the structure of liquid GaSb does not contract uniformly. Corresponding to the shift of the first peak, the coordination number increases. These results show that the local structure in liquid GaSb changes into a more highly coordinated state under pressure.

  17. Sonochemical preparation of SbSeI gel.

    Science.gov (United States)

    Nowak, M; Kauch, B; Szperlich, P; Jesionek, M; Kepińska, M; Bober, Ł; Szala, J; Moskal, G; Rzychoń, T; Stróz, D

    2009-04-01

    A novel sonochemical method for direct preparation of nanocrystalline antimony selenoiodide (SbSeI) has been established. The SbSeI gel was synthesized using elemental Sb, Se, and I in the presence of ethanol under ultrasonic irradiation (35 kHz, 2W/cm(2)) at 50 degrees C for 2h. The product was characterized by using techniques such as powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), and optical diffuse reflection spectroscopy (DRS). The SEM and HRTEM investigations exhibit that the as-prepared samples are made up of large quantity nanowires with lateral dimensions of about 20-50 nm and lengths reaching up to several micrometers and single crystalline in nature.

  18. Quaternary InGaAsSb Thermophotovoltaic Diode Technology

    Energy Technology Data Exchange (ETDEWEB)

    M Dashiell; J Beausang; H Ehsani; G Nichols; D DePoy; L Danielson; P Talamo; K Rahner; E Brown; S Burger; P Fourspring; W Topper; P Baldasaro; C Wang; R Huang; M Connors; G Turner; Z Shellenbarger; G Taylor; Jizhong Li; R Martinelli; D Donetski; S Anikeev; G Belenky; S Luryl

    2005-01-26

    Thermophotovoltaic (TPV) diodes fabricated from InGaAsSb alloys lattice-matched to GaSb substrates are grown by Metal Organic Vapor Phase Epitaxy (MOVPE). 0.53eV InGaAsSb TPV diodes utilizing front-surface spectral control filters have been tested in a vacuum cavity and a TPV thermal-to-electric conversion efficiency ({eta}{sub TPV}) and a power density (PD) of {eta}{sub TPV} = 19% and PD=0.58 W/cm{sup 2} were measured for T{sub radiator} = 950 C and T{sub diode} = 27 C. Recombination coefficients deduced from minority carrier measurements and the theory reviewed in this article predict a practical limit to the maximum achievable conversion efficiency and power density for 0.53eV InGaAsSb TPV. The limits for the above operating temperatures are projected to be {eta}{sub TPV} = 26% and PD = 0.75 W/cm{sup 2}. These limits are extended to {eta}{sub TPV} = 30% and PD = 0.85W/cm{sup 2} if the diode active region is bounded by a reflective back surface to enable photon recycling and a two-pass optical path length. The internal quantum efficiency of the InGaAsSb TPV diode is close to the theoretically predicted limits, with the exception of short wavelength absorption in GaSb contact layers. Experiments show that the open circuit voltage of the 0.53eV InGaAsSb TPV diodes is not strongly dependent on the device architectures studied in this work where both N/P and P/N double heterostructure diodes have been grown with various acceptor and donor doping levels, having GaSb and AlGaAsSb confinement, and also partial back surface reflectors. Lattice matched InGaAsSb TPV diodes were fabricated with bandgaps ranging from 0.6 to 0.5eV without significant degradation of the open circuit voltage factor, quantum efficiency, or fill factor as the composition approached the miscibility gap. The key diode performance parameter which is limiting efficiency and power density below the theoretical limits in InGaAsSb TPV devices is the open circuit voltage. The open circuit voltages of

  19. Growth and characterization of AlInAsSb layers lattice-matched to GaSb

    Science.gov (United States)

    Tournet, J.; Rouillard, Y.; Tournié, E.

    2017-11-01

    We report on the growth by solid-source MBE of random-alloy AlxIn1-xAsySb1-y layers lattice-matched to (0 0 1)-GaSb substrates, with xAl ∈ [0.25; 0.75]. The samples quality and morphology were characterized by X-ray diffraction, Nomarski microscopy and atomic force microscopy. Layers grown at 400 °C demonstrated smooth surfaces and no sign of phase decomposition. Samples with xAl ≤ 0.60 demonstrated photoluminescence (PL) at 300 K whereas samples with higher Al content only demonstrated PL at low temperature. Samples grown at 430 °C, in contrast, exhibited PL at low temperature only, whatever their composition. Inferred bandgap energies corroborate the estimation of a non-null quaternary bowing parameter made by Donati, Kaspi and Malloy in Journal of Applied Physics 94 (2003) 5814. Upon annealing, the PL peak energies increased, getting even closer to the theoretical values. These results are in agreement with recently published results on digital AlInAsSb alloys. Our work, which reports the first evidence for PL emission from random-alloy AlInAsSb layers lattice-matched to GaSb, opens the way to their use in optoelectronic devices.

  20. Effect of Sb in thick InGaAsSbN layers grown by liquid phase epitaxy

    Science.gov (United States)

    Donchev, V.; Milanova, M.; Asenova, I.; Shtinkov, N.; Alonso-Álvarez, D.; Mellor, A.; Karmakov, Y.; Georgiev, S.; Ekins-Daukes, N.

    2018-02-01

    Dilute nitride InGaAsSbN layers grown by low-temperature liquid phase epitaxy are studied in comparison with quaternary InGaAsN layers grown at the same growth conditions to understand the effect of Sb in the alloy. The lattice mismatch to the GaAs substrate is found to be slightly larger for the InGaAsSbN layers, which is explained by the large atomic radius of Sb. A reduction of the band gap energy with respect to InGaAsN is demonstrated by means of photoluminescence (PL), surface photovoltage (SPV) spectroscopy and tight-binding calculations. The band-gap energies determined from PL and ellipsometry measurements are in good agreement, while the SPV spectroscopy and the tight-binding calculations provide lower values. Possible reasons for these discrepancies are discussed. The PL spectra reveal localized electronic states in the band gap near the conduction band edge, which is confirmed by SPV spectroscopy. The analysis of the power dependence of the integrated PL has allowed determining the dominant radiative recombination mechanisms in the layers. The values of the refraction index in a wide spectral region are found to be higher for the Sb containing layers.

  1. Retention of As and Sb in ombrotrophic peat bogs: records of As, Sb, and Pb deposition at four Scottish sites

    Energy Technology Data Exchange (ETDEWEB)

    Joanna M. Cloy; John G. Farmer; Margaret C. Graham; Angus B. MacKenzie [University of Edinburgh, Edinburgh (United Kingdom). School of GeoSciences

    2009-03-15

    Possible postdepositional As migration in ombrotrophic peat bogs was investigated by comparing depth profiles of As with those of Sb and Pb, two elements considered to be essentially immobile in peat, and those of redox-sensitive, potentially mobile nutrient elements such as Mn, Fe, P, and S in {sup 210}Pb-dated cores from four Scottish bogs. Concentration profiles of As were similar to those of Sb and Pb rather than these other elements, indicating that As is bound strongly to organic matter and is relatively immobile in ombrotrophic peat. Historical records of atmospheric anthropogenic As, Sb, and Pb deposition during the industrial and postindustrial periods were derived, site-specific maxima (up to 1.55, 1.33, and 45 mg m{sup -2} y{sup -1}, respectively) occurring between the late 1890s and 1960s, reflecting emissions from diverse sources such as mining and smelting, coal combustion, and also, in the case of Pb, exhaust emissions from the use of leaded gasoline. Since the mid-1980s, fluxes of Pb decreased (4-7 fold) more rapidly than those of As and Sb (2-3 fold), attributable to both the gradual elimination of leaded gasoline and recent new sources of the latter elements. Relative trends in derived anthropogenic As, Sb, and Pb deposition largely agreed with other Scottish peat and moss archive records, direct measurements of deposition, and UK emissions, i.e., four different types of data source. 36 refs., 3 figs., 1 tab.

  2. Retention of As and Sb in ombrotrophic peat bogs: records of As, Sb, and Pb deposition at four Scottish sites.

    Science.gov (United States)

    Cloy, Joanna M; Farmer, John G; Graham, Margaret C; MacKenzie, Angus B

    2009-03-15

    Possible postdepositional As migration in ombrotrophic peat bogs was investigated by comparing depth profiles of As with those of Sb and Pb, two elements considered to be essentially immobile in peat, and those of redox-sensitive, potentially mobile nutrient elements such as Mn, Fe, P, and S in 210Pb-dated cores from four Scottish bogs. Concentration profiles of As were similar to those of Sb and Pb rather than these other elements, indicating that As is bound strongly to organic matter and is relatively immobile in ombrotrophic peat. Historical records of atmospheric anthropogenic As, Sb, and Pb deposition during the industrial and postindustrial periods were derived, site-specific maxima (up to 1.55, 1.33, and 45 mg m(-2) y(-1), respectively) occurring between the late 1890s and 1960s, reflecting emissions from diverse sources such as mining and smelting, coal combustion, and also, in the case of Pb, exhaust emissions from the use of leaded gasoline. Since the mid-1980s, fluxes of Pb decreased (4-7 fold) more rapidly than those of As and Sb (2-3 fold), attributable to both the gradual elimination of leaded gasoline and recent new sources of the latter elements. Relative trends in derived anthropogenic As, Sb, and Pb deposition largely agreed with other Scottish peat and moss archive records, direct measurements of deposition, and UK emissions, i.e., four different types of data source.

  3. Enhanced Li- and Na-storage in Sb-Graphene nanocomposite anodes

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Yeongjae; Shim, Hyun-Woo; Seo, Seung-Deok [School of Civil, Environmental and Architectural Engineering, Korea University, Seoul 136-713 (Korea, Republic of); Dar, Mushtaq Ahmad [Center of Excellence for Research in Engineering Materials, Advanced Manufacturing Institute, King Saud University,Riyadh 11421 (Saudi Arabia); Kim, Dong-Wan, E-mail: dongwan1@empal.com [School of Civil, Environmental and Architectural Engineering, Korea University, Seoul 136-713 (Korea, Republic of)

    2016-04-15

    Highlights: • Antimony-graphene nanocomposite (Sb-GNP) was prepared by a wet-chemical approach. • Sb-GNP exhibits the well-dispersed Sb nanoparticles anchored on the graphenes. • Sb-GNP shows highly reversible capacities in both Li- and Na-storage. - Abstract: Antimony-graphene nanocomposite (Sb-GNP) was prepared from commercially available graphene nanoplatelets (GNPs) by a simple wet-chemical route at room temperature, and systematically investigated as an anode material for both lithium- and sodium-ion batteries (LIBs and NIBs). The microstructural features of Sb-GNP, and of pure Sb nanoparticles prepared without addition of GNPs, were characterized using X-ray diffraction, field-emission scanning electron microscopy, and high-resolution transmission electron microscopy. The successful formation of a nanocomposite structure was observed for Sb-GNP; the Sb nanoparticles are well dispersed and anchored on graphene nanoplatelets without significant aggregation of Sb nanoparticles, in contrast to the pure Sb nanoparticles. Furthermore, galvanostatic studies revealed that Sb-GNP displays better Li- and Na-storage performance than the pure Sb nanoparticles when utilized as an anode material. The enhanced electrochemical performance can be attributed to the effects of nanocomposite formation with GNPs.

  4. Coulomb excitation of 104Sn and the strength of the 100Sn shell closure.

    Science.gov (United States)

    Guastalla, G; DiJulio, D D; Górska, M; Cederkäll, J; Boutachkov, P; Golubev, P; Pietri, S; Grawe, H; Nowacki, F; Sieja, K; Algora, A; Ameil, F; Arici, T; Atac, A; Bentley, M A; Blazhev, A; Bloor, D; Brambilla, S; Braun, N; Camera, F; Dombrádi, Zs; Domingo Pardo, C; Estrade, A; Farinon, F; Gerl, J; Goel, N; Grȩbosz, J; Habermann, T; Hoischen, R; Jansson, K; Jolie, J; Jungclaus, A; Kojouharov, I; Knoebel, R; Kumar, R; Kurcewicz, J; Kurz, N; Lalović, N; Merchan, E; Moschner, K; Naqvi, F; Nara Singh, B S; Nyberg, J; Nociforo, C; Obertelli, A; Pfützner, M; Pietralla, N; Podolyák, Z; Prochazka, A; Ralet, D; Reiter, P; Rudolph, D; Schaffner, H; Schirru, F; Scruton, L; Sohler, D; Swaleh, T; Taprogge, J; Vajta, Zs; Wadsworth, R; Warr, N; Weick, H; Wendt, A; Wieland, O; Winfield, J S; Wollersheim, H J

    2013-04-26

    A measurement of the reduced transition probability for the excitation of the ground state to the first 2+ state in 104Sn has been performed using relativistic Coulomb excitation at GSI. 104Sn is the lightest isotope in the Sn chain for which this quantity has been measured. The result is a key point in the discussion of the evolution of nuclear structure in the proximity of the doubly magic nucleus 100Sn. The value B(E2; 0+ → 2+) = 0.10(4) e2b2 is significantly lower than earlier results for 106Sn and heavier isotopes. The result is well reproduced by shell model predictions and therefore indicates a robust N = Z = 50 shell closure.

  5. Coulomb Excitation of Sn104 and the Strength of the Sn100 Shell Closure

    Science.gov (United States)

    Guastalla, G.; DiJulio, D. D.; Górska, M.; Cederkäll, J.; Boutachkov, P.; Golubev, P.; Pietri, S.; Grawe, H.; Nowacki, F.; Sieja, K.; Algora, A.; Ameil, F.; Arici, T.; Atac, A.; Bentley, M. A.; Blazhev, A.; Bloor, D.; Brambilla, S.; Braun, N.; Camera, F.; Dombrádi, Zs.; Domingo Pardo, C.; Estrade, A.; Farinon, F.; Gerl, J.; Goel, N.; Grȩbosz, J.; Habermann, T.; Hoischen, R.; Jansson, K.; Jolie, J.; Jungclaus, A.; Kojouharov, I.; Knoebel, R.; Kumar, R.; Kurcewicz, J.; Kurz, N.; Lalović, N.; Merchan, E.; Moschner, K.; Naqvi, F.; Nara Singh, B. S.; Nyberg, J.; Nociforo, C.; Obertelli, A.; Pfützner, M.; Pietralla, N.; Podolyák, Z.; Prochazka, A.; Ralet, D.; Reiter, P.; Rudolph, D.; Schaffner, H.; Schirru, F.; Scruton, L.; Sohler, D.; Swaleh, T.; Taprogge, J.; Vajta, Zs.; Wadsworth, R.; Warr, N.; Weick, H.; Wendt, A.; Wieland, O.; Winfield, J. S.; Wollersheim, H. J.

    2013-04-01

    A measurement of the reduced transition probability for the excitation of the ground state to the first 2+ state in Sn104 has been performed using relativistic Coulomb excitation at GSI. Sn104 is the lightest isotope in the Sn chain for which this quantity has been measured. The result is a key point in the discussion of the evolution of nuclear structure in the proximity of the doubly magic nucleus Sn100. The value B(E2;0+→2+)=0.10(4) e2b2 is significantly lower than earlier results for Sn106 and heavier isotopes. The result is well reproduced by shell model predictions and therefore indicates a robust N=Z=50 shell closure.

  6. Fabrication and characterization of photoelectrochemically-active Sb-doped Snx-W(100-x)%-oxide anodes: Towards the removal of organic pollutants from wastewater

    Science.gov (United States)

    Ghasemian, Saloumeh; Omanovic, Sasha

    2017-09-01

    Snx-W(100-x)-oxide coatings (x = 0, 20, 40, 60, 80 and 100) doped with Sb (∼3 at.%) were formed on a Ti substrate by a thermal deposition method in order to evaluate their potential use as electrodes for the photoelectrochemical oxidation of organic compounds. Surface microstructure/morphology and chemical composition of the coatings, as well as their photoelectrocatalytic activities were investigated using electrochemical and surface-characterization techniques. It was found that the surface roughness of the coatings depends on their composition, yielding an average value of Ra = 1.1 ± 0.5 μm. The band gap energy was found to be independent on the coating composition up to the relative W/Sn at. ratio of 4/6, yielding an average value of 3.53 ± 0.05 eV (which corresponds to the band gap of doped SnO2), but then it decreased for the three coatings with the highest W content, to an average value of 2.56 ± 0.10 eV (which corresponds to the value of pure WO3). All the coatings were found to be photoactive under the anodic bias. Further, all the coatings were found to be photoelectrochemically active towards the degradation of phenol red dye solution under UV light irradiation. The intrinsic photoelectrocatalytic activity was found to be highest for the Sn80%-W20%-oxide electrode coating.

  7. Electrochemical characterization of the Au-In-Sb system

    Directory of Open Access Journals (Sweden)

    Gomidželović Lidija D.

    2009-01-01

    Full Text Available The Au-In-Sb system belongs to the group of potential candidates for new lead-free solder materials. Therefore, a lot of investigations concerning its phase diagram and thermodynamic, mechanical, physical characteristics are going on at the moment. Having in mind the significance of such materials application in electronics, it is also very important to study their electrochemical characteristics. In order to give such a characterization, the results of cyclic voltammetry measurements for some alloys in the Au-In-Sb system are presented in this paper.

  8. Synthesis and Thermoelectric Properties of CuSbS2

    OpenAIRE

    Gao, Tianyue; Fang, Haiyu; Wu, Yue

    2014-01-01

    Copper antimony sulfide, CuSbS2 nanoparticles have a large potential of being a good thermoelectric material because they are made up of earth abundant elements. Thermoelectric materials can convert thermal energy into electricity, so that the wasted energy can be saved. Also, by using this earth abundant material, we can make thermoelectric materials much cheaper. The hypothesis of this study is that CuSbS2 could have a large Seebeck coefficient, one of the most important factors of thermoel...

  9. Lead activity in Pb-Sb-Bi alloys

    Directory of Open Access Journals (Sweden)

    A. S. Kholkina

    2014-11-01

    Full Text Available The present work is devoted to the study of lead thermodynamic activity in the Pb-Sb-Bi alloys. The method for EMF measurements of the concentration cell: (–Pb|KCl-PbCl2¦¦KCl-PbCl2|Pb-(Sb-Bi(+ was used. The obtained concentration dependences of the galvanic cell EMF are described by linear equations. The lead activity in the ternary liquid-metal alloy demonstrates insignificant negative deviations from the behavior of ideal solutions.

  10. Thermodynamic data for the speciation and solubility of Pd, Pb, Sn, Sb, Nb and Bi in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Lothenbach, B.; Ochs, M. [BMG Engineering Ltd., Zuerich-Schlieren (Switzerland); Wanner, H.; Yui, Mikazu

    1999-01-01

    This report provides thermodynamic data for predicting concentrations of palladium, lead, tin, antimony, niobium and bismuth in geologic environments, and contributes to an integration of the JNC chemical thermodynamic database, JNC-TDB (previously PNC-TDB), for the performance analysis of geological isolation system of high-level radioactive wastes. Besides treating hydrolysis in detail, this report focuses on the formation of complexes or compounds with chloride, fluoride, carbonate, nitrate, sulfate and phosphate. Other important inorganic ligands (sulfide for lead and antimony, ammonia for palladium) are also included. In this study, the specific ion interaction theory (SIT) approach is used to extrapolate thermodynamic constants to zero ionic strength at 25degC. (author)

  11. Uncooled High-Performance InAsSb Focal Plane Arrays Project

    Data.gov (United States)

    National Aeronautics and Space Administration — SVT Associates proposes an innovative digital alloy technique to extend the cutoff wavelength of InAsSb beyond 5 um, a wider band gap InAlAsSb layer inserted into...

  12. Exposure Assessment of Sb2O3 in PET Food Contact Materials.

    Science.gov (United States)

    Zhu, Lei; Wang, Zhu Tian; Xu, Hai Bin; Sun, Ru Bao; Zhang, Hong; Zhang, Jian Bo

    2016-04-01

    This study was conducted to do exposure assessment of the possible migration of antimony trioxide (Sb2O3) from Polyethylene terephthalate (PET) food contact materials (FCM). Consumption Factor (CF) and Food-type Distribution Factor (fT) were calculated from survey data with reference to the US FDA method. The most conservative migration conditions were obtained by testing Sb migration from PET FCM based on the Chinese national standard of GB/T 5009.101-2003[1]. Migration levels of Sb from PET FCM were tested and migration levels of Sb2O3 were obtained through molecular weight conversion between Sb and Sb2O3. Exposure assessment of Sb2O3 was undertaken. The Chinese Estimated Daily Intake (EDI) of Sb2O3 resulted from PET FCM was 90.7 ng p-1d-1. Copyright © 2016 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

  13. InSb Nanowires with Built-In GaxIn1-xSb Tunnel Barriers for Majorana Devices.

    Science.gov (United States)

    Car, Diana; Conesa-Boj, Sonia; Zhang, Hao; Op Het Veld, Roy L M; de Moor, Michiel W A; Fadaly, Elham M T; Gül, Önder; Kölling, Sebastian; Plissard, Sebastien R; Toresen, Vigdis; Wimmer, Michael T; Watanabe, Kenji; Taniguchi, Takashi; Kouwenhoven, Leo P; Bakkers, Erik P A M

    2017-02-08

    Majorana zero modes (MZMs), prime candidates for topological quantum bits, are detected as zero bias conductance peaks (ZBPs) in tunneling spectroscopy measurements. Implementation of a narrow and high tunnel barrier in the next generation of Majorana devices can help to achieve the theoretically predicted quantized height of the ZBP. We propose a material-oriented approach to engineer a sharp and narrow tunnel barrier by synthesizing a thin axial segment of Ga x In 1-x Sb within an InSb nanowire. By varying the precursor molar fraction and the growth time, we accurately control the composition and the length of the barriers. The height and the width of the Ga x In 1-x Sb tunnel barrier are extracted from the Wentzel-Kramers-Brillouin (WKB) fits to the experimental I-V traces.

  14. Optical and structural characterization of GaSb and Te-doped GaSb single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Tirado-Mejia, L. [Laboratorio de Optoelectronica, Universidad del Quindio, A.A. 460, Armenia, Quindio (Colombia); Villada, J.A. [Centro de Investigacion y de Estudios Avanzados del IPN, Unidad Queretaro, Qro (Mexico); Rios, M. de los [Laboratorio de Optoelectronica, Universidad del Quindio, A.A. 460, Armenia, Quindio (Colombia); Penafiel, J.A. [Centro de Fisica Aplicada y Tecnologia Avanzada, Departamento de Nanotecnologia, Universidad Nacional Autonoma de Mexico, Campus Juriquilla, Queretaro, Qro (Mexico); Posgrado en Ciencia e Ingenieria Materiales, Universidad Nacional Autonoma de Mexico, Mexico (Mexico); Fonthal, G. [Laboratorio de Optoelectronica, Universidad del Quindio, A.A. 460, Armenia, Quindio (Colombia); Espinosa-Arbelaez, D.G. [Centro de Fisica Aplicada y Tecnologia Avanzada, Departamento de Nanotecnologia, Universidad Nacional Autonoma de Mexico, Campus Juriquilla, Queretaro, Qro (Mexico); Posgrado en Ciencia e Ingenieria Materiales, Universidad Nacional Autonoma de Mexico, Mexico (Mexico); Ariza-Calderon, H. [Laboratorio de Optoelectronica, Universidad del Quindio, A.A. 460, Armenia, Quindio (Colombia); Rodriguez-Garcia, M.E. [Centro de Fisica Aplicada y Tecnologia Avanzada, Departamento de Nanotecnologia, Universidad Nacional Autonoma de Mexico, Campus Juriquilla, Queretaro, Qro (Mexico)], E-mail: marioga@fata.unam.mx

    2008-11-30

    Optical and structural properties of GaSb and Te-doped GaSb single crystals are reported herein. Utilizing the photoreflectance technique, the band gap energy for doped samples was obtained at 0.814 eV. Photoluminescence (PL) spectra showed a peak at 0.748 eV that according to this research, belongs to electronic states of pure GaSb and not to the longitudinal optical (LO) phonon replica as has been reported by other authors. Analysis of the full width at half maximum (FWHM) values of X-ray diffraction, as well as micro-Raman peaks showed that the inclusion of Te decreases the crystalline quality.

  15. Chemistry, growth kinetics, and epitaxial stabilization of Sn2+ in Sn-doped SrTiO3 using (CH36Sn2 tin precursor

    Directory of Open Access Journals (Sweden)

    Tianqi Wang

    2016-12-01

    Full Text Available PbTiO3-based ferroelectrics have impressive electroactive properties, originating from the Pb2+ 6s2 electron lone-pair, which cause large elastic distortion and electric polarization due to cooperative pseudo Jahn-Teller effect. Recently, tin-based perovskite oxide (SnTiO3 containing Sn2+ and a chemistry similar to that of the 6s2 lone-pair has been identified as a thermally stable, environmentally friendly substitute for PbTiO3-based ferroelectrics. However experimental attempts to stabilize Sn2+ on the A-site of perovskite ATiO3 have so far failed. In this work, we report on the growth of atomically smooth, epitaxial, and coherent Sn-alloyed SrTiO3 films on SrTiO3 (001 substrates using a hybrid molecular beam epitaxy approach. With increasing Sn concentration, the out-of-plane lattice parameter first increases in accordance with the Vegard’s law and then decreases for Sn(Sr+Ti+Sn at. % ratio > 0.1 due to the incorporation of Sn2+ at the A-site. Using a combination of high-resolution X-ray photoelectron spectroscopy and density functional calculations, we show that while majority of Sn is on the B-site, there is a quantitatively unknown fraction of Sn being consistent with the A-site occupancy making SrTiO3 polar. A relaxor-like ferroelectric local distortion with monoclinic symmetry, induced by A-site Sn2+, was observed in Sn-doped SrTiO3 with Sn(Sr+Ti+Sn at. % ratio = 0.1 using optical second harmonic generation measurements. The role of growth kinetics on the stability of Sn2+ in SrTiO3 is discussed.

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

    Science.gov (United States)

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

    2009-09-08

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

  17. Competitive adsorption of As(III), As(V), Sb(III) and Sb(V) onto ferrihydrite in multi-component systems: Implications for mobility and distribution.

    Science.gov (United States)

    Qi, Pengfei; Pichler, Thomas

    2017-05-15

    The simultaneous adsorption behavior and competitive interactions between As(III), As(V), Sb(III) and Sb(V) by ferrihydrite were evaluated in multi-component (binary, ternary, quaternary) systems. In binary systems, Sb(III) had a stronger inhibitory influence on As(III) adsorption than Sb(V) did, and As(V) had a stronger inhibitory effect on Sb(V) adsorption than As(III) did. In ternary systems, NO3-, PO43- and SO42- did not compete with the adsorption of As(III) and Sb(III). NO3- and SO42- also had no distinct effect on the adsorption of As(V) and Sb(V), while PO43- competed with As(V) and Sb(V) for surface sites. In quaternary systems, the simultaneous adsorption behavior of the four redox species was pH dependent. Sb(III) always showed the strongest adsorption affinity regardless of pH. At pH 3.5 As(III) showed the lowest affinity could be due to the presence and negative effect of Sb(III) and As(V). The Freundlich model provided a good fit for the simultaneous adsorption data under quaternary conditions. The study of competitive/simultaneous adsorption of the four possible redox species onto ferrihydrite contributed to a better understanding of their distribution, mobility and fate in the environment. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. First-principles calculation of semiclassical thermoelectric properties of (AgSbSe{sub 2}){sub n}(AgSbTe{sub 2}){sub n} superlattices

    Energy Technology Data Exchange (ETDEWEB)

    Salimi, Marzieh [Department of Physics, Isfahan University of Technology, 84156-83111 Isfahan (Iran, Islamic Republic of); Hashemifar, S. Javad, E-mail: hashemifar@cc.iut.ac.ir [Department of Physics, Isfahan University of Technology, 84156-83111 Isfahan (Iran, Islamic Republic of); Nanotechnology and Advanced Materials Institute, Isfahan University of Technology (Iran, Islamic Republic of)

    2015-11-25

    In this research, we perform density functional – pseudo potential calculation within generalized gradient approximation (GGA) to investigate semiclassical thermoelectric properties of (AgSbSe{sub 2}){sub n}(AgSbTe{sub 2}){sub n} (n = 1,2) thin film superlattices. It is seen that GGA, GGA + U, and the modified Becke Johnson (mBJ) functionals as well as full-relativistic corrections are not able to describe properly the electronic structure of bulk AgSbSe{sub 2} and AgSbTe{sub 2}, hence a scissor correction is used throughout this study. The Seebeck coefficient, electrical conductivity, and electronic part of the thermal conductivity of bulk compounds as well as superlattices are computed at different values of hole doping, in the fixed relaxation time approximation. It is argued that the (AgSbSe{sub 2}){sub 1}(AgSbTe{sub 2}){sub 1} superlattice may exhibits improved Seebeck coefficient compared with the bulk compounds and (AgSbSe{sub 2}){sub 2}(AgSbTe{sub 2}){sub 2} superlattice. - Highlights: • Ab initio study of (AgSbTe2)/(AgSbSe2) superlattice as a new thermoelectric system. • Computing Seebeck coefficient and power factor in relaxation time approximation. • Stable structure of the superlattices is determined. • Thermoelectric parameters of the superlattices are compared with the bulk materials.

  19. Sb2S3 thickness-dependent lateral photovoltaic effect and time response observed in glass/FTO/CdS/Sb2S3/Au structure.

    Science.gov (United States)

    Qiao, Shuang; Liu, Jihong; Li, ZhiQiang; Wang, ShuFang; Fu, GuangSheng

    2017-08-07

    As an interesting one dimensional ribbon material, Sb2S3 has recently attracted much attention in recent years due to its exciting optical properties. However, Sb2S3-based photovoltaic or photoelectronic devices are still in research, and there are many things unknown to us and need to be well studied. In this work, the glass/FTO/CdS/Sb2S3/Au structures were successfully prepared with different Sb2S3 thicknesses, and the lateral photovoltaic effect (LPE) was firstly observed in this structure, suggesting its great potential in position sensitivity detectors (PSD). It is demonstrated that the crystallinity of Sb2S3 film increases, and Sb2S3 film tends to be vertical ribbon orientation with increasing thickness. Owing to the strong light absorption of the thicker Sb2S3 film and its one dimensional ribbon like crystal structure, the LPE in the glass/FTO/CdS/Sb2S3/Au structure improves with increasing Sb2S3 thickness from 350 nm to 800 nm, and the glass/FTO/CdS/Sb2S3(800 nm) structure exhibits an unprecedented performance with position sensitivity as large as 2230.4 mV/mm. Moreover, the time response of photovoltage was also firstly measured in this structure, it is observed that both the rise time and the fall time decrease with increasing thickness from 350 nm to 800 nm, and then increase quickly for 1100 nm film, further verifing that the Sb2S3 thickness-dependent LPE is strongly dependent on the carriers' longitudinal transport time. The very large LPE and the relatively fast response speed observed in the glass/FTO/CdS/Sb2S3(800 nm)/Au structure unveils its great potential applications in the optoelectronic detectors and also bring an insight that the suitable thickness is very crucial in Sb2S3-based devices.

  20. Study of a SiGeSn/GeSn/SiGeSn structure toward direct bandgap type-I quantum well for all group-IV optoelectronics.

    Science.gov (United States)

    Ghetmiri, Seyed Amir; Zhou, Yiyin; Margetis, Joe; Al-Kabi, Sattar; Dou, Wei; Mosleh, Aboozar; Du, Wei; Kuchuk, Andrian; Liu, Jifeng; Sun, Greg; Soref, Richard A; Tolle, John; Naseem, Hameed A; Li, Baohua; Mortazavi, Mansour; Yu, Shui-Qing

    2017-02-01

    A SiGeSn/GeSn/SiGeSn single quantum well structure was grown using an industry standard chemical vapor deposition reactor with low-cost commercially available precursors. The material characterization revealed the precisely controlled material growth process. Temperature-dependent photoluminescence spectra were correlated with band structure calculation for a structure accurately determined by high-resolution x-ray diffraction and transmission electron microscopy. Based on the result, a systematic study of SiGeSn and GeSn bandgap energy separation and barrier heights versus material compositions and strain was conducted, leading to a practical design of a type-I direct bandgap quantum well.

  1. Single step hydrothermal based synthesis of M(II)Sb2O6 (M = Cd ...

    Indian Academy of Sciences (India)

    those reported in the literature (Mizoguchi and Woodward. 2004). In the case of NiSb2O6 and CuSb2O6, pyrochlore phase formation was also seen in addition to the desired pro- ducts, while the reaction was incomplete in the case of. PbSb2O6. The reaction of NaSbO3 with divalent metal salt solutions producing the oxides ...

  2. Antimony segregation in the oxidation of AlAsSb interlayers

    Science.gov (United States)

    Andrews, A. M.; van Horn, K. L.; Mates, T.; Speck, J. S.

    2003-11-01

    The lateral wet oxidation of strained AlAsSb was studied. AlAs0.80Sb0.20 interlayers were grown on a GaAs substrate and capped with a lattice-matched In0.25Ga0.75As layer. The AlAsSb was oxidized between 350 and 450 °C. Oxidation temperatures >400 °C resulted in poor surface morphology and delamination. Oxidation of thicker AlAsSb interlayers (h~2000 Å) resulted in metallic Sb layers forming between the AlOx and the semiconductor interfaces. The remaining Sb metal at the oxide-semiconductor interface was ~15% oxidized. Lateral wet oxidation of thinner AlAsSb interlayers (hMethanol (CH3OH) was added to the water mixture with the intent to stabilize the otherwise unstable stibine (SbH3) such that Sb could be removed from the oxidizing structure. However, methanol addition resulted in a decreased oxidation rate and a change in the Sb precipitate morphology. The Sb inclusions observed in pure water oxidation changed to a Sb finger-like morphology with increasing methanol concentration. The Sb fingers were 1.0-2.0 μm wide and as long as the oxidation depth. Oxidation of AlAsSb interlayers h<=200 Å were limited by the incorporation of Ga from the substrate and capping layer into the oxidation layer. Doping the oxidation AlAsSb interlayer 1×1018 cm-3 n type (Si or Te) did not result in any improvement in Sb segregation.

  3. Effects of FeSb6 octahedral deformations on the electronic structure of LaFe4Sb12

    KAUST Repository

    Pulikkotil, Jiji Thomas Joseph

    2011-09-01

    First-principles density functional based electronic structure calculations are performed in order to clarify the influence of FeSb6 octahedral deformations on the structural and electronic structure properties of LaFe 4Sb12. Our results show that octahedral tiltings correlate with the band dispersions and, consequently, the band masses. While total energy variation points at an enhanced role of lattice anharmonicity, flat bands emerge from a redistribution of the electronic states. © 2011 Elsevier B.V. All rights reserved.

  4. Effect of Silicon on Activity Coefficients of P, Bl, CD, SN, and AG in Liquid Fe-Si, and Implications for Differentiation and Core Formation

    Science.gov (United States)

    Righter, K.; Pando, K.; Ross, D. K.

    2017-01-01

    Cores of differentiated bodies (Earth, Mars, Mercury, Moon, Vesta) contain light elements such as S, C, Si, and O. We have previously measured small effects of Si on metal-silicate partitioning of Ni and Co [1,2], and larger effects for Mo, Ge, Sb, As [2]. The effect of Si on many siderophile elements could be an important, and as yet unquantified, influence on the core-mantle partitioning of SE. Here we report new experiments designed to quantify the effect of Si on the partitioning of Bi, Cd, Sn, Ag, and P between metal and silicate melt. The results will be applied to Earth, Mars, Mercury, Moon, and Vesta, for which we have excellent constraints on the mantle Bi, Cd, Sn, Ag, and P concentrations from mantle and/or basalt samples.

  5. Spin glass behavior of isolated, geometrically frustrated tetrahedra of iron atoms in the intermetallic La(21)Fe(8)Sn(7)C(12).

    Science.gov (United States)

    Benbow, Evan M; Dalal, Naresh S; Latturner, Susan E

    2009-03-11

    Metal flux synthesis in a low-melting eutectic mixture of lanthanum and nickel has produced a family of complex intermetallic carbide phases. La(21)Fe(8)M(7)C(12) (M = Sn, Bi, Sb, Te, Ge) has a new cubic structure featuring tetrahedra of iron atoms capped with carbon on each edge. These tetrahedra are surrounded by a La/M framework and are therefore isolated from each other. The antiferromagnetic coupling of the iron atoms is frustrated by their ideal tetrahedral arrangement; this is evidenced by magnetic susceptibility measurements on the La(21)Fe(8)Sn(7)C(12) analogue. Deviations from Curie-Weiss behavior begin at 100 K; variation in field-cooled vs zero-field-cooled behavior is seen at 5 K indicative of magnetic ordering. AC susceptibility data indicate that the temperature of this transition is frequency-dependent, behavior characteristic of spin glass systems.

  6. Crystal structure of [Ag(NH33]2[Ag(NH32]2[SnF6]F2, a compound showing argentophilic interactions

    Directory of Open Access Journals (Sweden)

    Florian Kraus

    2016-12-01

    Full Text Available Bis[triamminesilver(I] bis[diamminesilver(I] hexafluoridostannate(IV difluoride, [Ag(NH33]2[Ag(NH32]2[SnF6]F2, was obtained in the form of colourless crystals from the reaction of CsAgSnF7 in anhydrous ammonia. Two different ammine complexes of silver(I are present in the structure, i.e. a linear diammine and a T-shaped triammine complex. The ammine silver(I complexes show Ag...Ag distances in the range of argentophilic interactions. In the crystal, several N—H...F hydrogen bonds are present between the complex cations and the SbF6− and F− anions, leading to the formation of a three-dimensional network.

  7. Ultraviolet emission from low resistance Cu2SnS3/SnO2 and CuInS2/Sn:In2O3 nanowires

    Directory of Open Access Journals (Sweden)

    E. Karageorgou

    2014-11-01

    Full Text Available SnO2 and Sn:In2O3 nanowires were grown on Si(001, and p-n junctions were fabricated in contact with p-type Cu2S which exhibited rectifying current–voltage characteristics. Core-shell Cu2SnS3/SnO2 and CuInS2/Sn:In2O3 nanowires were obtained by depositing copper and post-growth processing under H2S between 100 and 500 °C. These consist mainly of tetragonal rutile SnO2 and cubic bixbyite In2O3. We observe photoluminescence at 3.65 eV corresponding to band edge emission from SnO2 quantum dots in the Cu2SnS3/SnO2 nanowires due to electrostatic confinement. The Cu2SnS3/SnO2 nanowires assemblies had resistances of 100 Ω similar to CuInS2/In2O3 nanowires which exhibited photoluminescence at 3.0 eV.

  8. Effect of Sb content on the thermoelectric properties of annealed CoSb{sub 3} thin films deposited via RF co-sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Aziz, E-mail: aziz_ahmed@ust.ac.kr [Department of Nano-Mechatronics, Korea University of Science and Technology (UST), 217 Gajeong-ro, Yuseong-gu, Daejeon, 305-350 (Korea, Republic of); Department of Nano-Mechanics, Korea Institute of Machinery and Materials (KIMM), 156 Gajeongbuk-ro, Yuseong-gu, Daejeon, 305-343 (Korea, Republic of); Han, Seungwoo, E-mail: swhan@kimm.re.kr [Department of Nano-Mechatronics, Korea University of Science and Technology (UST), 217 Gajeong-ro, Yuseong-gu, Daejeon, 305-350 (Korea, Republic of); Department of Nano-Mechanics, Korea Institute of Machinery and Materials (KIMM), 156 Gajeongbuk-ro, Yuseong-gu, Daejeon, 305-343 (Korea, Republic of)

    2017-06-30

    Graphical abstract: The X-ray diffraction patterns and temperature dependence of the Seebeck coefficient of the annealed Co–Sb thin films. - Highlights: • CoSb{sub 3} phase thin films were prepared using RF co sputtering method. • Thin film thermoelectric properties were hugely dependent on Sb content. • All thin films shows n-type conduction behavior at high temperatures. • The thin films with excess Sb possess the largest Seebeck coefficient. • The thin films with CoSb{sub 2} phase possess the largest power factor. - Abstract: A series of CoSb{sub 3} thin films with Sb contents in the range 70–79 at.% were deposited at room temperature via RF co-sputtering. The thin films were amorphous in the as-deposited state and annealed at 300 °C for 3 h to obtain crystalline samples. The annealed thin films were characterized using scanning electron microscopy and X-ray diffraction (XRD), and these data indicate that the films exhibited good crystallinity. The XRD patterns indicate single-phase CoSb{sub 3} thin films in the Sb-rich samples. For the Sb-deficient samples, however, mixed-phase thin films consisting of CoSb{sub 2} and CoSb{sub 3} components were obtained. The electrical and thermoelectric properties were measured at temperatures up to 760 K and found to be highly sensitive to the phases that were present. We observed a change in the thermoelectric properties of the films from p-type at low temperatures to n-type at high temperatures, which indicates potential applications as n-type thermoelectric thin films. A large Seebeck coefficient and power factor was obtained for the single-phase CoSb{sub 3} thin films. The CoSb{sub 2} phase thin films were also found to possess a significant Seebeck coefficient, which coupled with the much smaller electrical resistivity, provided a larger power factor than the single-phase CoSb{sub 3} thin films. We report maximum power factor of 7.92 mW/m K{sup 2} for the CoSb{sub 2}-containing mixed phase thin film and 1

  9. Draft Genome Sequence of Corynebacterium kefirresidentii SB, Isolated from Kefir

    Science.gov (United States)

    Blasche, Sonja; Kim, Yongkyu

    2017-01-01

    ABSTRACT The genus Corynebacterium includes Gram-positive species with a high G+C content. We report here a novel species, Corynebacterium kefirresidentii SB, isolated from kefir grains collected in Germany. Its draft genome sequence was remarkably dissimilar (average nucleotide identity, 76.54%) to those of other Corynebacterium spp., confirming that this is a unique novel species. PMID:28912312

  10. Experimental characterization of monocrystalline Si targets implanted with Sb + ions

    Science.gov (United States)

    Labbani, R.; Serrar, H.; Baouni, L.

    2010-02-01

    Monocrystalline silicon targets were submitted to a beam of antimony ions. The Si(1 1 1) substrates were implanted at an energy of 120 keV, at room temperature, to a dose varying from 1×10 15 to 5×10 15 Sb + cm -2. To recover the radiation defects generated by Sb + ions, a thermal annealing was performed, at 900 °C for 30 min under very high vacuum. The study of antimony ion implantation in the monocrystalline silicon targets was performed by means of different experimental techniques: X-ray diffraction, optical and electrical measurements. The perturbations enhanced by Sb + ion implantation and the recovery of the damage were investigated with great interest. Although the selected techniques are not frequently applied to investigate such phenomena, they have provided important results. In as-implanted specimens, it was found that the radiation damage increased with the increase of antimony dose. After the annealing treatment, a good recovery of defects was obtained especially in the samples implanted with the low dose (i.e. 1×10 15 Sb + cm -2).

  11. Optical characteristics of crystalline antimony sulphide (Sb 2 S 3 ...

    African Journals Online (AJOL)

    This paper presents the important optical characteristics of crystalline Sb2S3 film deposited on glass substrate using solution growth technique at 300k. These characteristics were analyzed using PYEUNICAM SP8-100 spectrophotometer in the range of UV-VIS-NIR while the morphology and the structural composition were ...

  12. Temperature Variation of the Magnetic Structure of HoSb

    DEFF Research Database (Denmark)

    Andersen, Nils Axel; Kjems, Jørgen; Vogt, O.

    1980-01-01

    Neutron diffraction has been used to show that the magnetic moment vector in the antiferromagnet HoSb changes direction as a function of temperature below TN=5.7K. The experimental results are in qualitative agreement with a recent theoretical prediction by Jensen et al. (1980) which ascribe...

  13. Commensurate-commensurate magnetic phase transitions in CeSb

    DEFF Research Database (Denmark)

    Lebech, Bente; Broholm, C.; Clausen, K.

    1986-01-01

    The q=2/3 to q=4/7 commensurate-commensurate phase transition in CeSb has been studied by neutron diffraction. On cooling the commensurate wave vector q changes abruptly from 2/3 to a higher-order commensurate value (≈14/23) at T1

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

    African Journals Online (AJOL)

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

  15. InAs/GaSb superlattice quality investigation

    Science.gov (United States)

    Henig, Aleksandra; Grodecki, Kacper; Murawski, Krzysztof; Michalczewski, Krystian; Kubiszyn, Łukasz; Benyahia, Djalal; Jankiewicz, Bartłomiej; Budner, Bogusław; Martyniuk, Piotr

    2017-08-01

    In this work we compare two InAs/GaSb superlattice samples grown in MBE VIGO/MUT laboratory on 2 inch (001) GaAs substrate, using MBE technique. Both samples have the same architecture, however their growth processes were conducted at different temperatures. For sample A the growth temperature was equal 668 K (395°C), for sample B 588 K (315°C). Photoluminescence measurements were performed at 30 K. For sample A there is no photoluminescence signal, while spectrum for sample B consists of two peaks: bandgap peak at 0.5 eV and deep state peak at 0.25 eV. X-ray diffraction (XRD) measurements indicate that sample A has better crystallographic quality than sample B. Raman spectra consists of low energy peaks (20-100 cm-1) which confirm the existence of superlattice for both samples [4]. Additionally, for sample A there are peaks related to Sb precipitates. It suggests that except the InAs/GaSb superlattice there is an additional Sb layer which may disturb band structure of superlattice and cause the disappearance of photoluminescence for sample A.

  16. Magnetic Phase Transitions of CeSb. I

    DEFF Research Database (Denmark)

    Fischer, Pernille Hertz; Lebech, Bente; Meier, G.

    1978-01-01

    The magnetic ordering of the anomalous antiferromagnet CeSb, which has a NaCl crystal structure, was determined in zero applied magnetic field by means of neutron diffraction investigations of single crystals and powder. Below the Neel temperature TN of (16.1+or-0.1)K, there exist six partially...

  17. Programming biological models in Python using PySB.

    Science.gov (United States)

    Lopez, Carlos F; Muhlich, Jeremy L; Bachman, John A; Sorger, Peter K

    2013-01-01

    Mathematical equations are fundamental to modeling biological networks, but as networks get large and revisions frequent, it becomes difficult to manage equations directly or to combine previously developed models. Multiple simultaneous efforts to create graphical standards, rule-based languages, and integrated software workbenches aim to simplify biological modeling but none fully meets the need for transparent, extensible, and reusable models. In this paper we describe PySB, an approach in which models are not only created using programs, they are programs. PySB draws on programmatic modeling concepts from little b and ProMot, the rule-based languages BioNetGen and Kappa and the growing library of Python numerical tools. Central to PySB is a library of macros encoding familiar biochemical actions such as binding, catalysis, and polymerization, making it possible to use a high-level, action-oriented vocabulary to construct detailed models. As Python programs, PySB models leverage tools and practices from the open-source software community, substantially advancing our ability to distribute and manage the work of testing biochemical hypotheses. We illustrate these ideas using new and previously published models of apoptosis.

  18. Spin-orbit interaction in InSb nanowires

    NARCIS (Netherlands)

    Van Weperen, I.; Tarasinski, B.; Eeltink, D.; Pribiag, V.S.; Plissard, S.R.; Bakkers, E.P.A.M.; Kouwenhoven, L.P.; Wimmer, M.T.

    2015-01-01

    We use magnetoconductance measurements in dual-gated InSb nanowire devices, together with a theoretical analysis of weak antilocalization, to accurately extract spin-orbit strength. In particular, we show that magnetoconductance in our three-dimensional wires is very different compared to wires in

  19. Knight shift measurements in the superconducting state of Pr{sub 1-x}La{sub x}Os{sub 4}Sb{sub 12}(x=0.4) probed by {mu}SR

    Energy Technology Data Exchange (ETDEWEB)

    Higemoto, W. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan)]. E-mail: higemoto.wataru@jaea.go.jp; Aoki, Y. [Department of Physics, Tokyo Metropolitan University of Hachioji, Tokyo 192-0397 (Japan); Ohishi, K. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Ito, T.U. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Department of Physics, Tokyo Institute of Technology, Meguro, Tokyo 152-8551 (Japan); Heffner, R.H. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195 (Japan); Saha, S.R. [Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801 (Japan); Koda, A. [Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801 (Japan); Satoh, K.H. [Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801 (Japan); Kadono, R. [Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801 (Japan); Kikuchi, D. [Department of Physics, Tokyo Metropolitan University of Hachioji, Tokyo 192-0397 (Japan); Sugawara, H. [Department of Mathematical and Natural Sciences, University of Tokushima, Tokushima 770-8502 (Japan); Sato, H. [Department of Physics, Tokyo Metropolitan University of Hachioji, Tokyo 192-0397 (Japan)

    2007-03-15

    We report a muon spin rotation study of a single crystalline sample of the heavy fermion superconductor Pr{sub 1-x}La{sub x}Os{sub 4}Sb{sub 1}2(x=0.4). The muon Knight shift is independent of temperature, passing through T{sub c} down to 20mK, suggesting that the local spin susceptibility does not decrease in the superconducting state.

  20. Rational design of Sn/SnO{sub 2}/porous carbon nanocomposites as anode materials for sodium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiaojia [Tianjin International Joint Research Centre of Surface Technology for Energy Storage Materials, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Li, Xifei, E-mail: xfli2011@hotmail.com [Tianjin International Joint Research Centre of Surface Technology for Energy Storage Materials, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Center for Advanced Energy Materials and Devices, Xi’an University of Technology, Xi’an 710048 (China); Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Collaborative Innovation Center of Chemical Science and Engineering, College of Chemistry, Nankai University, Tianjin 300071 (China); Fan, Linlin; Yu, Zhuxin; Yan, Bo; Xiong, Dongbin; Song, Xiaosheng; Li, Shiyu [Tianjin International Joint Research Centre of Surface Technology for Energy Storage Materials, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Adair, Keegan R. [Nanomaterials and Energy Lab., Department of Mechanical and Materials Engineering, Western University, London, Ontario N6A 5B9 (Canada); Li, Dejun, E-mail: dejunli@mail.tjnu.edu.cn [Tianjin International Joint Research Centre of Surface Technology for Energy Storage Materials, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Sun, Xueliang, E-mail: xsun9@uwo.ca [Nanomaterials and Energy Lab., Department of Mechanical and Materials Engineering, Western University, London, Ontario N6A 5B9 (Canada); Tianjin International Joint Research Centre of Surface Technology for Energy Storage Materials, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China)

    2017-08-01

    Highlights: • Sn/SnO{sub 2}/porous carbon nanocomposites are rationally designed via a facile strategy. • The porous carbon mitigates the volume change and poor conductivity of Sn/SnO{sub 2}. • The nanocomposites exhibit the enhanced sodium storage performance. - Abstract: Sodium-ion batteries (SIBs) have successfully attracted considerable attention for application in energy storage, and have been proposed as an alternative to lithium ion batteries (LIBs) due to the abundance of sodium resources and low price. Sn has been deemed as a promising anode material in SIBs which holds high theoretical specific capacity of 845 mAh g{sup −1}. In this work we design nanocomposite materials consisting of porous carbon (PC) with SnO{sub 2} and Sn (Sn/SnO{sub 2}/PC) via a facile reflux method. Served as an anode material for SIBs, the Sn/SnO{sub 2}/PC nanocomposite delivers the primary discharge and charge capacities of 1148.1 and 303.0 mAh g{sup −1}, respectively. Meanwhile, it can preserve the discharge capacity approximately of 265.4 mAh g{sup −1} after 50 cycles, which is much higher than those of SnO{sub 2}/PC (138.5 mAh g{sup −1}) and PC (92.2 mAh g{sup −1}). Furthermore, the Sn/SnO{sub 2}/PC nanocomposite possesses better cycling stability with 77.8% capacity retention compared to that of SnO{sub 2}/PC (61.88%) over 50 cycles. Obviously, the Sn/SnO{sub 2}/PC composite with excellent electrochemical performance shows the great possibility of application in SIBs.

  1. Hydrogen peroxide route to Sn-doped titania photocatalysts

    National Research Council Canada - National Science Library

    Štengl, Václav; Grygar, Tomáš Matys; Henych, Jiří; Kormunda, Martin

    2012-01-01

    .... Tin-doped titania catalysts were prepared by thermal hydrolysis of aqueous solutions of titanium peroxo-complexes in the presence of SnCl4 or SnCl2 using an original, proprietary "one pot" synthesis...

  2. Aluminum-stabilized NB3SN superconductor

    Science.gov (United States)

    Scanlan, Ronald M.

    1988-01-01

    An aluminum-stabilized Nb.sub.3 Sn superconductor and process for producing same, utilizing ultrapure aluminum. Ductile components are co-drawn with aluminum to produce a conductor suitable for winding magnets. After winding, the conductor is heated to convert it to the brittle Nb.sub.3 Sn superconductor phase, using a temperature high enough to perform the transformation but still below the melting point of the aluminum. This results in reaction of substantially all of the niobium, while providing stabilization and react-in-place features which are beneficial in the fabrication of magnets utilizing superconducting materials.

  3. Heavy Flavour Production

    OpenAIRE

    Nason, P; Ridolfi, G.; Frixione, S.

    1995-01-01

    We review the status of heavy flavour production in QCD. Comparison of experimental and theoretical results for top and bottom production are given. Selected topics in charm production are also discussed.

  4. Atmospheric Heavy Metal Pollution

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 6; Issue 4. Atmospheric Heavy Metal Pollution - Development of Chronological Records and Geochemical Monitoring. Rohit Shrivastav. General Article Volume 6 Issue 4 April 2001 pp 62-68 ...

  5. Heavy Quarks: Summary Report

    CERN Document Server

    Baines, J.; Behnke, O.; Bracinik, J.; Cacciari, M.; Corradi, M.; Dainese, A.; Diglio, S.; Eskola, K.J.; Eynck, T.O.; Geiser, A.; Grindhammer, G.; Jung, H.; Kniehl, B.A.; Kolhinen, V.J.; Kretzer, S.; Kutak, K.; Laenen, Eric; Lagouri, Th.; Lipatov, A.V.; Maltoni, F.; Martin, A.D.; Meyer, A.; Morsch, A.; Motyka, L.; Peters, K.; Petrucci, F.; Piskounova, O.I.; Ranieri, R.; Ruiz, H.; Ryskin, M.G.; Schienbein, I.; Smith, J.; Smizanska, M.; Spiesberger, H.; Tonazzo, A.; Uwer, U.; Verducci, M.; Vogt, R.; Weiser, C.; Zotov, N.P.; Lagouri, Th.

    2006-01-01

    The present status of the heavy-quark production theory is critically reviewed in the first contribution. The second contribution summarises the present heavy flavour data from HERA and gives an outlook of what can be expected from HERA-II. The potential of the LHC experiments for charm and beauty physics is reviewed in the 3rd contribution. Then the relevance of saturation and small-x effects to heavy quark production at HERA and at the LHC are discussed. The non-perturbative aspects of heavy-quark fragmentation and their relevance to HERA and LHC are discussed in the next contribution. Finally, a comparison of different theoretical predictions for HERA and LHC based on different approaches is presented.

  6. Quaternary InGaAsSb Thermophotovoltaic Diodes

    Energy Technology Data Exchange (ETDEWEB)

    MW Dashiell; JF Beausang; H Ehsani; GJ Nichols; DM Depoy; LR Danielson; P Talamo; KD Rahner; EJ Brown; SR Burger; PM Foruspring; WF Topper; PF Baldasaro; CA Wang; R Huang; M Connors; G Turner; Z Shellenbarger; G Taylor; J Li; R Martinelli; D Donetski; S Anikeev; G Belenky; S Luryi

    2006-03-09

    In{sub x}Ga{sub 1-x}As{sub y}Sb{sub 1-y} thermophotovoltaic (TPV) diodes were grown lattice-matched to GaSb substrates by Metal Organic Vapor Phase Epitaxy (MOVPE) in the bandgap range of E{sub G} = 0.5 to 0.6eV. InGaAsSb TPV diodes, utilizing front-surface spectral control filters, are measured with thermal-to-electric conversion efficiency and power density of {eta}{sub TPV} = 19.7% and PD =0.58 W/cm{sup 2} respectively for a radiator temperature of T{sub radiator} = 950 C, diode temperature of T{sub diode} = 27 C, and diode bandgap of E{sub G} = 0.53eV. Practical limits to TPV energy conversion efficiency are established using measured recombination coefficients and optical properties of front surface spectral control filters, which for 0.53eV InGaAsSb TPV energy conversion is {eta}{sub TPV} = 28% and PD = 0.85W/cm{sup 2} at the above operating temperatures. The most severe performance limits are imposed by (1) diode open-circuit voltage (VOC) limits due to intrinsic Auger recombination and (2) parasitic photon absorption in the inactive regions of the module. Experimentally, the diode V{sub OC} is 15% below the practical limit imposed by intrinsic Auger recombination processes. Analysis of InGaAsSb diode electrical performance vs. diode architecture indicate that the V{sub OC} and thus efficiency is limited by extrinsic recombination processes such as through bulk defects.

  7. Tin (Sn) for enhancing performance in silicon CMOS

    KAUST Repository

    Hussain, Aftab M.

    2013-10-01

    We study a group IV element: tin (Sn) by integrating it into silicon lattice, to enhance the performance of silicon CMOS. We have evaluated the electrical properties of the SiSn lattice by performing simulations using First-principle studies, followed by experimental device fabrication and characterization. We fabricated high-κ/metal gate based Metal-Oxide-Semiconductor capacitors (MOSCAPs) using SiSn as channel material to study the impact of Sn integration into silicon. © 2013 IEEE.

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

    Energy Technology Data Exchange (ETDEWEB)

    Song, Wenjuan [State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011 (China); Zhang, Daoyong [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 (China); Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan (China); Pan, Xiangliang, E-mail: xlpan@ms.xjb.ac.cn [State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011 (China); Lee, Duu-Jong [State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011 (China); Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan (China)

    2013-04-15

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

  9. Complete Genome Sequences of Pseudomonas monteilii SB3078 and SB3101, Two Benzene-, Toluene-, and Ethylbenzene-Degrading Bacteria Used for Bioaugmentation

    Science.gov (United States)

    Albertsen, Mads; D’Imperio, Seth; Tale, Vaibhav P.; Lewis, Derrick; Nielsen, Per Halkjær; Nielsen, Jeppe Lund

    2014-01-01

    Pseudomonas monteilii SB3078 and SB3101 are benzene-, toluene-, and ethylbenzene-degrading strains used for bioaugmentation in relation to treatment of wastewater contaminated with petrochemical hydrocarbons. Complete genome sequencing of the bioaugmentation strains confirms that they are very closely related (100.0% average nucleotide identity). Both strains contain extensive integration of phage elements, with the main difference being insertion of additional phage elements in the SB3078 genome. PMID:24874689

  10. Electrodeposition of Ni on Bi2Te3 and Interfacial Reaction Between Sn and Ni-Coated Bi2Te3

    Science.gov (United States)

    Tseng, Yu-Chen; Lee, Hsuan; Hau, Nga Yu; Feng, Shien-Ping; Chen, Chih-Ming

    2018-01-01

    Bismuth-telluride (Bi2Te3)-based compounds are common thermoelectric materials used for low-temperature applications, and nickel (Ni) is usually deposited on the Bi2Te3 substrates as a diffusion barrier. Deposition of Ni on the p-type (Sb-doped) and n-type (Se-doped) Bi2Te3 substrates using electroplating and interfacial reactions between Sn and Ni-coated Bi2Te3 substrates are investigated. Electrodeposition of Ni on different Bi2Te3 substrates is characterized based on cyclic voltammetry and Tafel measurements. Microstructural characterizations of the Ni deposition and the Sn/Ni/Bi2Te3 interfacial reactions are performed using scanning electron microscopy. A faster growth rate is observed for the Ni deposition on the n-type Bi2Te3 substrate which is attributed to a lower activation energy of reduction due to a higher density of free electrons in the n-type Bi2Te3 material. The common Ni3Sn4 phase is formed at the Sn/Ni interfaces on both the p-type and n-type Bi2Te3 substrates, while the NiTe phase is formed at a faster rate at the interface between Ni and n-type Bi2Te3 substrates.

  11. Nb 3Sn material development in Russia

    Science.gov (United States)

    Pantsyrny, V.; Shikov, A.; Vorobieva, A.

    2008-07-01

    In the USSR and later in Russia, the main activities in technical superconductivity were concentrated in the institutes that belonged to the Ministry of Atomic Energy (Minatom). The development of new technologies shortly transferred to the large-scale industrial production of NbTi and Nb 3Sn superconductors in early 1970s. Two main technologies for multifilamentary Nb 3Sn strands were under investigation during that time - bronze-process and internal tin method. More than 25 ton of Nb 3Sn bronze-processed strands were produced for the fabrication of 90 ton of conductors for application in the magnet system of first in the world fusion facility (tokamak T-15) with magnet system based on the intermetallic compound. The characteristics of these strands and conductors have been briefly described. The requirements for the Nb 3Sn strands constantly increased and the main R&D on the enhancement of critical current density have been reviewed. For bronze-processed strands the increase of the tin content in large ingots was the crucial factor. The artificial doping of niobium filaments by niobium-titanium alloy was invented, which enabled to improve the workability of Nb 3Sn strands, with enhanced critical current density in high fields. For internal tin Nb 3Sn strands the main R&D were concentrated on the optimization of the layouts of the strand and on the multistage heat treatment because of the inevitable liquid phase formation which could result in severe distortion of the geometrical arrangement of the filaments and even in destruction of the whole strand. The main results of these investigations have been presented. The corresponding impact of these R&D on the design of bronze-processed and internal tin strands has been analyzed. The quantitative estimations of the grain size were made for bronze-processed and internal tin strands. It was shown that in bronze-processed and internal tin strands subjected to the standard ITER heat treatment characterized by two stages

  12. Diffusion-Controlled Solid-State Formation of CoSb Phase from Co/Sb-Multilayered Nanowires

    Directory of Open Access Journals (Sweden)

    Seong Gi Jeon

    2012-01-01

    Full Text Available The physical properties of materials on a nanometer scale are known to be different from those of bulk form due to dimensional confinement effects and high specific surface-to-volume ratio. In this study, the size effects on the diffusion and reaction at the interface of dissimilar nanowires (NWs were investigated. Co/Sb-multilayered NWs of 15±1 and 19±2 nm in radius have been grown within anodic aluminum oxide templates using a pulsed potentiodynamic electrodeposition method. XRD and TEM results demonstrated that the multilayered NWs were transformed to a CoSb phase through a solid-state reaction at the temperature in the range of 653 to 693 K. The kinetics of the solid-state reaction was analyzed and found to be diffusion controlled at the interface between Co and Sb phases. The reaction was controlled by the dominant diffusion of Sb atoms. The activation energies for the solid-state reaction were estimated to be 0.9 and 0.7 eV/atom for the multilayered NWs with radii of 15 and 19 nm, respectively.

  13. Sludge batch 9 (SB9) accepance evaluation: Radionuclide concentrations in tank 51 SB9 qualification sample prepared at SRNL

    Energy Technology Data Exchange (ETDEWEB)

    Bannochie, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Diprete, D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Pareizs, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-03-01

    Presented in this report are radionuclide concentrations required as part of the program of qualifying Sludge Batch 9 (SB9) for processing in the Defense Waste Processing Facility (DWPF). The SB9 material is currently in Tank 51 and has been washed and prepared for transfer to Tank 40. The acceptance evaluation needs to be completed prior to the transfer of the material in Tank 51 to Tank 40. The sludge slurry in Tank 40 has already been qualified for DWPF processing and is currently being processed as Sludge Batch 8 (SB8). The radionuclide concentrations were measured or estimated in the Tank 51 SB9 Washed Qualification Sample prepared at Savannah River National Laboratory (SRNL). This sample was prepared from a three liter sample of Tank 51 sludge slurry (HTF-51-15-81) taken on July 23, 2015. The sample was delivered to SRNL where it was initially characterized in the Shielded Cells. Under the direction of Savannah River Remediation (SRR) it was then adjusted per the Tank Farm washing strategy as of October 20, 2015. This final slurry now has a compositioniv expected to be similar to that of the slurry in Tank 51 after final preparations have been made for transfer of that slurry to Tank 40.

  14. Sludge batch 9 (SB9) acceptance evaluation. Radionuclide concentrations in tank 51 SB9 qualification sample prepared at SRNL

    Energy Technology Data Exchange (ETDEWEB)

    Bannochie, C. J. [Savannah River Site (SRS), Aiken, SC (United States); Diprete, D. P. [Savannah River Site (SRS), Aiken, SC (United States); Pareizs, J. M. [Savannah River Site (SRS), Aiken, SC (United States)

    2016-02-10

    Presented in this report are radionuclide concentrations required as part of the program of qualifying Sludge Batch 9 (SB9) for processing in the Defense Waste Processing Facility (DWPF). The SB9 material is currently in Tank 51 and has been washed and prepared for transfer to Tank 40. The acceptance evaluation needs to be completed prior to the transfer of the material in Tank 51 to Tank 40. The sludge slurry in Tank 40 has already been qualified for DWPF processing and is currently being processed as Sludge Batch 8 (SB8). The radionuclide concentrations were measured or estimated in the Tank 51 SB9 Washed Qualification Sample prepared at Savannah River National Laboratory (SRNL). This sample was prepared from a three liter sample of Tank 51 sludge slurry (HTF-51-15-81) taken on July 23, 2015. The sample was delivered to SRNL where it was initially characterized in the Shielded Cells. Under the direction of Savannah River Remediation (SRR) it was then adjusted per the Tank Farm washing strategy as of October 20, 2015. This final slurry now has a composition expected to be similar to that of the slurry in Tank 51 after final preparations have been made for transfer of that slurry to Tank 40.

  15. Spliceosomal small nuclear RNAs of Tetrahymena thermophila and some possible snRNA-snRNA base-pairing interactions

    DEFF Research Database (Denmark)

    Orum, H; Nielsen, Henrik; Engberg, J

    1991-01-01

    organisms. Furthermore, secondary structures closely similar to phylogenetically proven models can be inferred from the T. thermophila data. Analysis of the snRNA sequences identifies three potential snRNA-snRNA base-pairing interactions, all of which are consistent with available phylogenetic data. Two......We have identified and characterized the full set of spliceosomal small nuclear RNAs (snRNAs; U1, U2, U4, U5 and U6) from the ciliated protozoan Tetrahymena thermophila. With the exception of U4 snRNA, the sizes of the T. thermophila snRNAs are closely similar to their metazoan homologues. The T....... thermophila snRNAs all have unique 5' ends, which start with an adenine residue. In contrast, with the exception of U6, their 3' ends show some size heterogeneity. The primary sequences of the T. thermophila snRNAs contain the sequence motifs shown, or proposed, to be of functional importance in other...

  16. Growth and thermoelectric properties of FeSb2 films produced by pulsed laser deposition

    DEFF Research Database (Denmark)

    Sun, Ye; Canulescu, Stela; Sun, Peijie

    2011-01-01

    Thermoelectric FeSb2 films were produced by pulsed laser deposition on silica substrates in a low-pressure Ar environment. The growth conditions for near phase-pure FeSb2 films were confirmed to be optimized at a substrate temperature of 425°C, an Ar pressure of 2 Pa, and deposition time of 3 h b...... by ablating specifically prepared compound targets made of Fe and Sb powders in atomic ratio of 1:4. The thermoelectric transport properties of FeSb2 films were investigated. Pulsed laser deposition was demonstrated as a method for production of good-quality FeSb2 films....

  17. Metallic Sn spheres and SnO2@C core-shells by anaerobic and aerobic catalytic ethanol and CO oxidation reactions over SnO2 nanoparticles

    Science.gov (United States)

    Kim, Won Joo; Lee, Sung Woo; Sohn, Youngku

    2015-01-01

    SnO2 has been studied intensely for applications to sensors, Li-ion batteries and solar cells. Despite this, comparatively little attention has been paid to the changes in morphology and crystal phase that occur on the metal oxide surface during chemical reactions. This paper reports anaerobic and aerobic ethanol and CO oxidation reactions over SnO2 nanoparticles (NPs), as well as the subsequent changes in the nature of the NPs. Uniform SnO2@C core-shells (10 nm) were formed by an aerobic ethanol oxidation reaction over SnO2 NPs. On the other hand, metallic Sn spheres were produced by an anaerobic ethanol oxidation reaction at 450 °C, which is significantly lower than that (1200 °C) used in industrial Sn production. Anaerobic and aerobic CO oxidation reactions were also examined. The novelty of the methods for the production of metallic Sn and SnO2@C core-shells including other anaerobic and aerobic reactions will contribute significantly to Sn and SnO2-based applications. PMID:26300041

  18. Enhanced nucleon transfer in tip collisions of 238U+124Sn

    Science.gov (United States)

    Sekizawa, Kazuyuki

    2017-10-01

    Multinucleon transfer processes in low-energy heavy ion reactions have attracted increasing interest in recent years aiming at the production of new neutron-rich isotopes. Clearly, it is an imperative task to further develop understanding of underlying reaction mechanisms to lead experiments to success. In this paper, from systematic time-dependent Hartree-Fock calculations for the 238U+124Sn reaction, it is demonstrated that transfer dynamics depend strongly on the orientations of 238U, quantum shells, and collision energies. Two important conclusions are obtained: (i) Experimentally observed many-proton transfer from 238U to 124Sn can be explained by a multinucleon transfer mechanism governed by enhanced neck evolution in tip collisions; (ii) novel reaction dynamics are observed in tip collisions at energies substantially above the Coulomb barrier, where a number of nucleons are transferred from 124Sn to 238U, producing transuranium nuclei as primary reaction products, which could be a means to synthesize superheavy nuclei. Both results indicate the importance of the neck (shape) evolution dynamics, which are sensitive to orientations, shell effects, and collision energies, for exploring possible pathways to produce new unstable nuclei.

  19. A MISSING-LINK IN THE SUPERNOVA–GRB CONNECTION: THE CASE OF SN 2012ap

    Energy Technology Data Exchange (ETDEWEB)

    Chakraborti, Sayan; Soderberg, Alicia; Kamble, Atish; Margutti, Raffaella; Milisavljevic, Dan; Dittmann, Jason [Institute for Theory and Computation, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Chomiuk, Laura [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Yadav, Naveen; Ray, Alak [Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400005 (India); Hurley, Kevin [Space Sciences Laboratory, University of California, 7 Gauss Way, Berkeley, CA 94720 (United States); Bietenholz, Michael [Department of Physics and Astronomy, York University, 4700 Keele St., M3J 1P3 Ontario (Canada); Brunthaler, Andreas [Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, D-53121 Bonn (Germany); Pignata, Giuliano [Departamento de Ciencias Fisicas, Universidad Andres Bello, Avda. Republica 252, Santiago (Chile); Pian, Elena [Scuola Normale Superiore, Piazza Dei Cavalieri 7—I-56126 Pisa (Italy); Mazzali, Paolo [Liverpool John Moores University, IC2, 146 Brownlow Hill, Liverpool (United Kingdom); Fransson, Claes [Department of Astronomy, Stockholm University, AlbaNova, SE-106 91 Stockholm (Sweden); Bartel, Norbert [Hartebeesthoek Radio Astronomy Observatory, PO Box 443, Krugersdrop, 1740 (South Africa); Hamuy, Mario [Departamento de Astronoma, Universidad de Chile (Chile); Levesque, Emily [University of Colorado, C327A, Boulder, CO 80309 (United States); MacFadyen, Andrew, E-mail: schakraborti@fas.harvard.edu [New York University, 4 Washington Place, New York, NY 10003 (United States); and others

    2015-06-01

    Gamma-ray bursts (GRBs) are characterized by ultra-relativistic outflows, while supernovae are generally characterized by non-relativistic ejecta. GRB afterglows decelerate rapidly, usually within days, because their low-mass ejecta rapidly sweep up a comparatively larger mass of circumstellar material. However, supernovae with heavy ejecta can be in nearly free expansion for centuries. Supernovae were thought to have non-relativistic outflows except for a few relativistic ones accompanied by GRBs. This clear division was blurred by SN 2009bb, the first supernova with a relativistic outflow without an observed GRB. However, the ejecta from SN 2009bb was baryon loaded and in nearly free expansion for a year, unlike GRBs. We report the first supernova discovered without a GRB but with rapidly decelerating mildly relativistic ejecta, SN 2012ap. We discovered a bright and rapidly evolving radio counterpart driven by the circumstellar interaction of the relativistic ejecta. However, we did not find any coincident GRB with an isotropic fluence of more than one-sixth of the fluence from GRB 980425. This shows for the first time that central engines in SNe Ic, even without an observed GRB, can produce both relativistic and rapidly decelerating outflows like GRBs.

  20. Taiwan's industrial heavy metal pollution threatens terrestrial biota

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, M.J. [Department of Biological Sciences, National Sun Yat-sen University, Kaohsiung 804, Taiwan (China); Selvaraj, K. [Institute of Marine Geology and Chemistry, National Sun Yat-sen University, Kaohsiung 804, Taiwan (China); Agoramoorthy, G. [Department of Pharmacy, Tajen University, Yanpu, Pingtung 907, Taiwan (China)]. E-mail: agoram@mail.tajen.edu.tw

    2006-09-15

    The bioconcentration levels of essential (Cu, Fe, Mg, Mn, and Zn) and non-essential (As, Cd, Hg, Pb, and Sn) elements have been investigated in different terrestrial biota such as fungi, plant, earthworm, snail, crab, insect, amphibian, lizard, snake, and bat including the associated soil, to investigate the ecosystem health status in Kenting National Park, Taiwan. High bioconcentrations of Cd, Hg, and Sn in snail, earthworm, crab, lizard, snake, and bat indicated a contaminated terrestrial ecosystem. High concentrations of Cd, Hg, and Sn in plant species, effective bioaccumulation of Cd by earthworm, snail, crab and bat, as well as very high levels of Hg found in invertebrates, amphibians, and reptiles revealed a strong influence from industrial pollution on the biotic community. This study for the first time presents data on the impact of heavy metal pollution on various terrestrial organisms in Taiwan. - Metal effects occur at any terrestrial levels in Taiwan.

  1. Crystal structure of the TbZnSn{sub 2} and TbZnSn ternary compounds

    Energy Technology Data Exchange (ETDEWEB)

    Pavlyuk, V. [Ivan Franko National University of Lviv, Department of Inorganic Chemistry, Kyryla and Mefodia Street 6, 79005 Lviv (Ukraine); Czestochowa Jan Dlugosz University, Institute of Chemistry and Environmental Protection, al. Armii Krajowej 13/15, 42200 Czestochowa (Poland)], E-mail: pavlyuk@franko.lviv.ua; Oshchapovsky, I. [Ivan Franko National University of Lviv, Department of Inorganic Chemistry, Kyryla and Mefodia Street 6, 79005 Lviv (Ukraine); Marciniak, B. [Czestochowa Jan Dlugosz University, Institute of Chemistry and Environmental Protection, al. Armii Krajowej 13/15, 42200 Czestochowa (Poland)

    2009-05-27

    The crystal structures of the TbZnSn{sub 2} and TbZnSn compounds were determined by X-ray single crystal diffraction. The TbZnSn{sub 2} compound crystallizes with the HfCuSi{sub 2} structure type (space group P4/nmm) and TbZnSn crystallizes with the YPtAs structure type (space group P6{sub 3}/mmc)

  2. Photo and electroluminescence of ZnSe: Sn and ZnSe:(Sn, Pr) phosphors

    Science.gov (United States)

    Mishra, A. K.; Mishra, S. K.; Pandey, S. P.; Lakshmi Mishra, Kshama

    2016-09-01

    We have prepared ZnSe (luminescent grade) phosphor doped with Sn and (Sn,Pr) with varying concentration in an inert atmosphere in a silica tubular furnace at temperature of (780 ± 20) °C for 1 hr to obtain ZnSe:Sn and ZnSe: (Sn,Pr) phosphors. The photo luminescence (PL) and electroluminescence (EL) spectra of these phosphors have been studied at room temperature and results were discussed in the light of existing models. Dependence of EL emission on the voltage frequency has also been carried out. It is found that the plot between the integrated light intensity versus 1/√Vrms is a straight line suggesting the existence of Mott-Schottky type barrier on the metal semiconductor interface.

  3. SnAs-Based Layered Superconductor NaSn2As2

    Science.gov (United States)

    Goto, Yosuke; Yamada, Akira; Matsuda, Tatsuma D.; Aoki, Yuji; Mizuguchi, Yoshikazu

    2017-12-01

    Superconducting behavior with exotic characteristics is often observed in materials with a layered two-dimensional crystal structure. Low dimensionality affects the electronic structure of these materials, potentially leading to high transition temperatures (Tc) and/or unconventional pairing mechanisms. In this letter, we report on superconductivity in layered tin arsenide NaSn2As2. The crystal structure consists of Sn2As2 bilayers, bound by the van der Waals forces and separated by Na+ ions. Measurements of electrical resistivity and specific heat confirm the bulk nature of superconductivity of NaSn2As2, with Tc of 1.3 K. Our results suggest that layered SnAs is a basic structure, offering another universality class in the family of layered superconductors. The results provide a new platform for the studies of physics and chemistry of low-dimensional superconductors with lone pair electrons.

  4. Atomic intermixing and segregation at the interface of InAs/GaSb type II superlattices

    Science.gov (United States)

    Li, Xiaochao; Zhang, Yong; Jiang, Dongwei; Guo, Fengyun; Wang, Dongbo; Zhao, Liancheng

    2017-04-01

    To determine the interfacial atomic intermixing of the InAs/GaSb T2SL, an innovative and straightforward method based on TEM techniques is proposed to analysize and investigate the interface stoichiometry of the InAs/GaSb T2SL. Using this method, the chemical components of the interfaces in InAs/GaSb T2SL can be quantitatively determined by fitting with the sigmoidal function and Muraki's segregation model. It is found that the intermixing at the cationic and anionic sublattice is different, and the interface GaSb-on-InAs is slightly sharper than the InAs-on-GaSb interface. Furthermore, we identified segregation of Sb and In atoms and quantitatively measured their incorporation in the lattice. It is also found that the In and Sb segregations mainly occur at the GaSb-on-InAs and InAs-on-GaSb interfaces, respectively and the Sb segregation is larger than the In segregation in the as-grown InAs/GaSb superlattice because of the different atomic exchanges energy.

  5. Electronic structures of Si- and Te-doped CoSb3 compounds under high pressures

    Science.gov (United States)

    Kobayashi, Kazuaki; Ullah Khan, Atta; Mori, Takao

    2017-05-01

    The electronic and lattice properties of various Si- and Te-doped CoSb3 compounds under hydrostatic compression conditions were calculated by using the total energy pseudopotential method. The calculated compositions of Si- and Te-doped CoSb3 compounds are Co8Sb22Si2, Co8Sb22Te2, Co8Sb21Si2Te1, and Co8Sb21Si1Te2. The applied pressure P values are 0 (ambient), 10, and 100 GPa. The densities of states (DOSs) of Si- and Te-doped CoSb3 compounds under P = 0, 10, and 100 GPa are investigated to compare them with each other. Their DOS shapes and Fermi level positions vary under pressure. In particular, the variations in DOS shape between P = 10 and 100 GPa in Co8Sb21Si2Te1 and Co8Sb21Si1Te2 are markedly large, although they are relatively small between P = 0 and 10 GPa. The gap states of Co8Sb21Si2Te1 and Co8Sb21Si1Te2 around the Fermi level disappear under P = 100 GPa. Seebeck coefficients do not increase under high pressures.

  6. Electromodulation spectroscopy of direct optical transitions in Ge{sub 1−x}Sn{sub x} layers under hydrostatic pressure and built-in strain

    Energy Technology Data Exchange (ETDEWEB)

    Dybała, F.; Żelazna, K.; Maczko, H.; Gladysiewicz, M.; Misiewicz, J.; Kudrawiec, R., E-mail: robert.kudrawiec@pwr.wroc.pl [Faculty of Fundamental Problems of Technology, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wrocław (Poland); Lin, H.; Chen, R.; Shang, C.; Huo, Y.; Kamins, T. I.; Harris, J. S. [Solid State and Photonics Laboratory, Stanford University, Stanford, California 94305-4075 (United States)

    2016-06-07

    Unstrained Ge{sub 1−x}Sn{sub x} layers of various Sn concentration (1.5%, 3%, 6% Sn) and Ge{sub 0.97}Sn{sub 0.03} layers with built-in compressive (ε = −0.5%) and tensile (ε = 0.3%) strain are grown by molecular beam epitaxy and studied by electromodulation spectroscopy (i.e., contactless electroreflectance and photoreflectance (PR)). In order to obtain unstrained GeSn layers and layers with different built-in in-plane strains, virtual InGaAs substrates of different compositions are grown prior to the deposition of GeSn layers. For unstrained Ge{sub 1−x}Sn{sub x} layers, the pressure coefficient for the direct band gap transition is determined from PR measurements at various hydrostatic pressures to be 12.2 ± 0.2 meV/kbar, which is very close to the pressure coefficient for the direct band gap transition in Ge (12.9 meV/kbar). This suggests that the hydrostatic deformation potentials typical of Ge can be applied to describe the pressure-induced changes in the electronic band structure of Ge{sub 1−x}Sn{sub x} alloys with low Sn concentrations. The same conclusion is derived for the uniaxial deformation potential, which describes the splitting between heavy-hole (HH) and light-hole (LH) bands as well as the strain-related shift of the spin-orbit (SO) split-off band. It is observed that the HH, LH, and SO related transitions shift due to compressive and tensile strain according to the Bir-Pikus theory. The dispersions of HH, LH, and SO bands are calculated for compressive and tensile strained Ge{sub 0.97}Sn{sub 0.03} with the 8-band kp Hamiltonian including strain effects, and the mixing of HH and LH bands is discussed. In addition, the dispersion of the electronic band structure is calculated for unstrained Ge{sub 1−x}Sn{sub x} layers (3% and 6% Sn) at high hydrostatic pressure with the 8-band kp Hamiltonian, and the pressure-induced changes in the electronic band structure are discussed.

  7. Nb3Sn superconducting magnets for electron cyclotron resonance ion sources.

    Science.gov (United States)

    Ferracin, P; Caspi, S; Felice, H; Leitner, D; Lyneis, C M; Prestemon, S; Sabbi, G L; Todd, D S

    2010-02-01

    Electron cyclotron resonance (ECR) ion sources are an essential component of heavy-ion accelerators. Over the past few decades advances in magnet technology and an improved understanding of the ECR ion source plasma physics have led to remarkable performance improvements of ECR ion sources. Currently third generation high field superconducting ECR ion sources operating at frequencies around 28 GHz are the state of the art ion injectors and several devices are either under commissioning or under design around the world. At the same time, the demand for increased intensities of highly charged heavy ions continues to grow, which makes the development of even higher performance ECR ion sources a necessity. To extend ECR ion sources to frequencies well above 28 GHz, new magnet technology will be needed in order to operate at higher field and force levels. The superconducting magnet program at LBNL has been developing high field superconducting magnets for particle accelerators based on Nb(3)Sn superconducting technology for several years. At the moment, Nb(3)Sn is the only practical conductor capable of operating at the 15 T field level in the relevant configurations. Recent design studies have been focused on the possibility of using Nb(3)Sn in the next generation of ECR ion sources. In the past, LBNL has worked on the VENUS ECR, a 28 GHz source with solenoids and a sextupole made with NbTi operating at fields of 6-7 T. VENUS has now been operating since 2004. We present in this paper the design of a Nb(3)Sn ECR ion source optimized to operate at an rf frequency of 56 GHz with conductor peak fields of 13-15 T. Because of the brittleness and strain sensitivity of Nb(3)Sn, particular care is required in the design of the magnet support structure, which must be capable of providing support to the coils without overstressing the conductor. In this paper, we present the main features of the support structure, featuring an external aluminum shell pretensioned with water

  8. Near-infrared SN Ia Cosmology

    Science.gov (United States)

    Avelino, Arturo; Kirshner, Robert; Mandel, Kaisey; Challis, Peter; Friedman, Andrew; RAISIN Team

    2018-01-01

    Observations of SN Ia in the near infrared (NIR) are a promising way to construct an accurate cosmic expansion history to constrain the properties of dark energy. SN Ia are more nearly standard candles in NIR than in optical bands, while dust absorption is less of a problem at NIR wavelengths. This allows us to investigate the dark energy properties in a way that is less sensitive to systematic errors due to the variations in the intrinsic brightness of SN Ia or the properties of dust in their host galaxies. In this talk, I present preliminary results from our RAISIN 1 (HST GO-13046) and RAISIN 2 (HST GO-14216) programs with the Hubble Space Telescope, where we have constructed a Hubble diagram combining optical + NIR photometric data using a sample of low and high redshift SN Ia. I will discuss our current results, challenges, and the advantage of using optical + NIR data to derive accurate cosmic distances and improve knowledge of the dark energy equation of state. This research is supported by NSF grants AST-156854 and AST-1211196.

  9. SN 1006 and other historical supernovae

    Science.gov (United States)

    Stephenson, F. Richard

    2007-08-01

    The supernova which appeared in AD 1006 is unique in history for its brilliance, duration of visibility, and the interest it aroused. Almost thirty separate records of the star are preserved from various parts of the world. This paper briefly summarizes historical records of SN 1006 and discusses the prospects of uncovering further historical records of supernovae.

  10. Sn and three-body forces

    Indian Academy of Sciences (India)

    c Indian Academy of Sciences. Vol. 85, No. 3. — journal of. September 2015 physics pp. 403–413. 136. Sn and three-body forces. M SAHA SARKAR1,∗ and S SARKAR2. 1Saha Institute of ... 2Indian Institute of Engineering Science and Technology, Shibpur, Howrah 711 103, India ... So far, experimental investigations.

  11. A fast synthesis for Zintl phase compounds of Na 3SbTe 3, NaSbTe 2 and K 3SbTe 3 by microwave irradiation

    Science.gov (United States)

    Zhou, Gen-Tao; Pol, V. G.; Palchik, Oleg; Kerner, Riki; Sominski, Elena; Koltypin, Yuri; Gedanken, Aharon

    2004-01-01

    The microwave irradiation technique was used to prepare three Zintl phase compounds Na 3SbTe 3, NaSbTe 2 and K 3SbTe 3. The as-prepared products were analyzed and characterized by XRD, EDX and SEM techniques. Higher microwave oven power and shorter irradiation time are required for the synthesis of Na 3SbTe 3, whereas lower oven power and longer irradiation time are needed for NaSbTe 2. Moderate microwave irradiation conditions facilitate the formation of pure K 3SbTe 3. Pure phase of Na 3SbTe 3 are directly obtained by this technique for the first time. Compared with the traditional high-temperature solid-state synthesis, the microwave reaction required a considerable shortened reaction time for the preparation of the three Zintl compounds. The initial driving force for these reactions originates from the interaction of microwave electric field with alkali metals (Na and K) and Sb powders.

  12. Intermetallic Formation and Fluidity in Sn-Rich Sn-Cu-Ni Alloys

    Science.gov (United States)

    Gourlay, C. M.; Nogita, K.; Read, J.; Dahle, A. K.

    2010-01-01

    This paper investigates the phase equilibria and solidification behavior of Sn-Cu-Ni alloys with compositions in the range of 0 wt.% to 1.5 wt.% Cu and 0 wt.% to 0.3 wt.% Ni. The isothermal section at 268°C in the Sn-rich corner was determined. No evidence for a ternary phase was found, and the section is in good agreement with past experimental studies that report wide solubility ranges for (Cu,Ni)6Sn5 and (Ni,Cu)3Sn4. The vacuum fluidity test was applied to compositions that are liquid at 268°C to map the variation in microstructure and flow behavior with composition in this system. Significant variations in fluidity length were measured among the Sn-Cu-Ni alloys, and the variations correlate with the microstructure that develops during solidification. The generated fluidity map enables the selection of Sn-Cu-Ni solder compositions that exhibit good fluidity behavior during solidification and form near-eutectic microstructures.

  13. Surface passivation and conversion of SnO{sub 2} to SnS{sub 2} nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Zervos, M., E-mail: zervos@ucy.ac.cy [Nanostructured Materials and Devices Laboratory and Department of Mechanical and Manufacturing Engineering, University of Cyprus, P.O. Box 20537, Nicosia 1678 (Cyprus); Mihailescu, C.N. [Nanotechnology Research Center and Department of Mechanical and Manufacturing Engineering, University of Cyprus, P.O. Box 20537, Nicosia 1678 (Cyprus); National Institute for Laser, Plasma and Radiation Physics, Str. Atomistilor, P.O. Box MG-36, 077125 Magurele (Romania); Giapintzakis, J. [Nanotechnology Research Center and Department of Mechanical and Manufacturing Engineering, University of Cyprus, P.O. Box 20537, Nicosia 1678 (Cyprus); Othonos, A. [Center of Ultrafast Science, Nanotechnology Research Center and Department of Physics, University of Cyprus, P.O. Box 20537, Nicosia 1678 (Cyprus); Luculescu, C.R. [National Institute for Laser, Plasma and Radiation Physics, Str. Atomistilor, P.O. Box MG-36, 077125 Magurele (Romania)

    2015-08-15

    Highlights: • SnO{sub 2} nanowires contain SnS{sub 2} after exposure to H{sub 2}S up to 300 °C. • The resistance of SnO{sub 2} nanowires is reduced significantly after exposure to H{sub 2}S at 300 °C. • SnO{sub 2} nanowires are fully converted to SnS{sub 2} at 400 °C under H{sub 2}S. • The photoluminescence of SnO{sub 2}/SnS{sub 2} nanowires does not change upon exposure to H{sub 2}S. • SnO{sub 2} nanowires are converted into SnS{sub 2} crystals upon exposure to H{sub 2}S above 400 °C. - Abstract: SnO{sub 2} nanowires have been grown on Si(0 0 1) via the vapour–liquid–solid mechanism at 800 °C and then exposed to H{sub 2}S between 300 and 600 °C. The SnS{sub 2}/SnO{sub 2} nanowires obtained at 300 °C consist of tetragonal rutile SnO{sub 2} and hexagonal SnS{sub 2}, exhibited defect related photoluminescence at 2.4 eV and have smaller resistances than the SnO{sub 2} nanowires. We show how the Fermi level pinning at the surface of a SnS{sub 2}/SnO{sub 2} nanowire would lead to an increase of the one dimensional electron gas density, smaller barrier height and resistance. The SnO{sub 2} nanowires are fully converted into hexagonal SnS{sub 2} at 400 °C resulting into photoluminescence at 2.4 and 2.8 eV but have considerably larger resistances than the SnO{sub 2} nanowires which are eliminated and converted into SnS{sub 2} crystals above 400 °C.

  14. GaSb solar cells grown on GaAs via interfacial misfit arrays for use in the III-Sb multi-junction cell

    Science.gov (United States)

    Nelson, George T.; Juang, Bor-Chau; Slocum, Michael A.; Bittner, Zachary S.; Laghumavarapu, Ramesh B.; Huffaker, Diana L.; Hubbard, Seth M.

    2017-12-01

    Growth of GaSb with low threading dislocation density directly on GaAs may be possible with the strategic strain relaxation of interfacial misfit arrays. This creates an opportunity for a multi-junction solar cell with access to a wide range of well-developed direct bandgap materials. Multi-junction cells with a single layer of GaSb/GaAs interfacial misfit arrays could achieve higher efficiency than state-of-the-art inverted metamorphic multi-junction cells while forgoing the need for costly compositionally graded buffer layers. To develop this technology, GaSb single junction cells were grown via molecular beam epitaxy on both GaSb and GaAs substrates to compare homoepitaxial and heteroepitaxial GaSb device results. The GaSb-on-GaSb cell had an AM1.5g efficiency of 5.5% and a 44-sun AM1.5d efficiency of 8.9%. The GaSb-on-GaAs cell was 1.0% efficient under AM1.5g and 4.5% at 44 suns. The lower performance of the heteroepitaxial cell was due to low minority carrier Shockley-Read-Hall lifetimes and bulk shunting caused by defects related to the mismatched growth. A physics-based device simulator was used to create an inverted triple-junction GaInP/GaAs/GaSb model. The model predicted that, with current GaSb-on-GaAs material quality, the not-current-matched, proof-of-concept cell would provide 0.5% absolute efficiency gain over a tandem GaInP/GaAs cell at 1 sun and 2.5% gain at 44 suns, indicating that the effectiveness of the GaSb junction was a function of concentration.

  15. Growth of Sb2S3 nanowires synthesized by colloidal process and self-assembly of amorphous spherical Sb2S3 nanoparticles in wires formation

    Science.gov (United States)

    Validžić, Ivana Lj.; Abazović, Nadica D.; Mitrić, Miodrag

    2012-12-01

    We report the organic synthesis and growth of antimony sulfide (Sb2S3) amorphous nanospheres to nanowires via a simple, colloidal synthetic method. Amorphous Sb2S3 nanospheres self-assembly in wires formation was dispersed in isopropyl alcohol. With increased heating time, Sb2S3 nanospheres grew into Sb2S3 nanowires, probably involving both mechanisms of Ostwald-ripening and spherical nanoparticle self-organization through oriented-attachment of individual nanoparticles. Also, the as-synthesized Sb2S3 nanowires with different heating times (0, 5 and 10 min.) from the moment of appearance of the Sb2S3 precipitate were analyzed. The observed nanowires become longer with increased heating time and are around 100 nm in diameter and 10-20 μm in length. UV-Vis absorption spectroscopy reveals that the optical band-gap energy of the Sb2S3 nanowires is independent of the heating times and is found to be ˜1.5-1.6 eV. The optical band-gap energy found for amorphous Sb2S3 nanospheres was also ˜1.5 eV. The structure of Sb2S3 samples was refined down to R-factors of 10.82, 11.76 and 12.08%. The refinement showed that Sb2S3 powder belongs to the orthorhombic type with space group Pbnm (no. 62) and that Sb2S3 nanowires grow along the [010] direction.

  16. Sb(V) and Sb(III) distribution in human erythrocytes: speciation methodology and the influence of temperature, time and anticoagulants.

    Science.gov (United States)

    Quiroz, Waldo; Aguilar, Luis; Barría, Macarena; Veneciano, Jocelyn; Martínez, Daniel; Bravo, Manuel; Lobos, María Gabriela; Mercado, Luis

    2013-10-15

    In this research a new method was developed and optimized for the determination of Sb(V) and Sb(III) in human erythrocytes fractions (plasma and cytoplasm) by high performance liquid chromatography with hydride generation atomic fluorescence spectrometry. The method considers the first step of samples cleaning by protein precipitation by salting out followed by C18 solid phase extraction, EDTA elution, and finally a chromatographic separation by using anion exchange PRPX-100 (100 mm × 4.1mm) and EDTA 20 mmol L(-1) as mobile phase. The method was optimized by experimental design with a recovery of 90% for Sb(V) and 55-75% for Sb(III) approximately. The analytical method was applied to study the distribution of Sb(V) and Sb(III) in human erythrocytes considering temperature and time of incubations and with special attention about the influence of the anticoagulant. Results showed that both Sb(V) and Sb(III) are capable to enter the red blood cell in a proportion of approximately 40-60%. On the other hand, both species are then excreted from the interior of the cell, where the percentage considerably decreased from approximately 60 to less than 30% within the cell. An increase in the culture temperature increases the capacity of Sb(V) and Sb(III) to penetrate the membrane barrier and reach the cytoplasm. In order to preserve the original distribution of Sb in blood, heparin seems to be the best anticoagulant for sample preservation. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Synthesis and Characterization of Sn2+- based and Bi3+- based metal oxides for photocatalytic applications

    KAUST Repository

    Noureldine, Dalal

    2016-07-01

    the compound at lower temperature. Next, the optoelectronic properties of α-SnWO4 structure were studied though a combination of experimental and theoretical approach. α-SnWO4 thin films were deposited by RF-sputtering. An interesting low band gap of ~ 1.95 eV was experimentally for direct band gap and 1.7 eV for indirect band gap, high dielectric constants and low electron effective masses in one crystallographic direction were obtained, exhibiting good charge separation and charge carrier transport of the charge carriers. The PEC performance was limited by the oxidation of Sn2+ in the material under applied potential. Finally, pyrochlore SnSb2O6 structure was synthesized utilizing soft hydrothermal method. The crystal structure was studied by Rietveld refinement and the position of Sn2+ was specified. The material showed interesting absorption edge around 700 which is promising for overall water splitting application.

  18. The use of compost. Its effects on heavy metal levels in soil and plants

    Energy Technology Data Exchange (ETDEWEB)

    Pinamonti, F.; Stringari, G.; Gasperi, F.; Zorzi, G. [Istituto Agrario di San Michele, San Michele all`Adige (Italy)

    1997-10-01

    Three organic soil conditioners were tested in 14 different Malus domestica orchards: cattle manure, SB compost (from sewage sludge and poplar barks) and MSW compost (from municipal solid waste not source separated). These materials differed notably in their heavy metal content: the SB compost contained greater amounts of Zn, Cu and Pb than did the cattle manure, while the MSW compost had higher concentrations of all the metals studied. For 6 years the Zn, Cu, Ni, Pb, Cd and Cr content were monitored in the soil- both in `total` and EDTA extractable form - and in leaves and fruits. The resulting data demonstrate that the SB compost did not cause any significant increase in heavy metal levels in soil and plants; this compost can thus be used to fertilise the soil with no danger in the short/medium term either to the environment or to crops. In contrast, the experiment clearly demonstrates that the MSW compost, used over a 6 year period, increased concentrations of Zn, Cu, Ni, Pb, Cd and Cr in the soil - both in `total` and EDTA extractable form - and in the case of Pb and Cd also in the vegetation and the fruits

  19. Diffusion couple studies of the Ni-Bi-Sn system

    Directory of Open Access Journals (Sweden)

    Vassilev G.

    2012-01-01

    Full Text Available Investigations of Ni-Bi-Sn system were performed in order to inquire the phase diagram and to assess some diffusion kinetic parameters. For this purpose diffusion couples consisting of solid nickel (preliminary electroplated with tin and liquid Bi-Sn phase were annealed at 370 °C. Three compositions (0.8, 0.6 and 0.4 mole fractions Sn of the Bi-Sn melts were chosen. Annealing times from 24 to 216 h were applied. The phase and chemical compositions of the contact zone were determined by means of electron scanning microscope. It was confirmed that the diffusion layers consist mainly of Ni3Sn4 but other intermetallic phases grow as well. For the first time metastable Ni-Sn phases as NiSn and NiSn8 (NiSn9 were observed in metallurgical alloys (i.e. not in electroplated samples. The existence of a ternary compound previously reported in the literature was confirmed. More than one ternary Ni-Bi-Sn compounds might possibly be admitted. A growth coefficient of (2.29 ± 0.02 x 10-15 m2 s-1 was obtained. It was found that the apparent activation energy for diffusion layers growth (18 ± 8 kJ mol-1 is inferior to that one assessed at growth from solid state Bi-Sn mixtures (88 ± 12 kJ mol-1.

  20. Martensitic Transformation in Ni-Mn-Sn-Co Heusler Alloys

    Directory of Open Access Journals (Sweden)

    Alexandre Deltell

    2015-04-01

    Full Text Available Thermal and structural austenite to martensite reversible transition was studied in melt spun ribbons of Ni50Mn40Sn5Co5, Ni50Mn37.5Sn7.5Co5 and Ni50Mn35Sn10Co5 (at. % alloys. Analysis of X-ray diffraction patterns confirms that all alloys have martensitic structure at room temperature: four layered orthorhombic 4O for Ni50Mn40Sn5Co5, four layered orthorhombic 4O and seven-layered monoclinic 14M for Ni50Mn37.5Sn7.5Co5 and seven-layered monoclinic 14M for Ni50Mn35Sn5Co5. Analysis of differential scanning calorimetry scans shows that higher enthalpy and entropy changes are obtained for alloy Ni50Mn37.5Sn7.5Co5, whereas transition temperatures increases as increasing valence electron density.

  1. Semiclassical approach to sequential fission in peripheral heavy-ion collisions

    Directory of Open Access Journals (Sweden)

    Strazzeri Andrea

    2016-01-01

    Full Text Available A closed-form theoretical approach describing in a single picture both the evaporation component and the fast nonequilibrium component of the sequential fission of projectilelike fragments in a semiperipheral heavy-ion collision is derived and then applied to the dynamical fission observed in the 124Sn+64Ni semiperipheral collision at 35A MeV. Information on opposite polarization effects of the fissioning projectilelike fragments and on their “formation-to-fast fission lifetimes” are obtained.

  2. GeSbTe deposition for the PRAM application

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Junghyun [Nano Fabrication Center, SAIT, Suwon, P.O. Box 111 (Korea, Republic of); Choi, Sangjoon [Nano Fabrication Center, SAIT, Suwon, P.O. Box 111 (Korea, Republic of); Lee, Changsoo [Nano Fabrication Center, SAIT, Suwon, P.O. Box 111 (Korea, Republic of); Kang, Yoonho [Nano Fabrication Center, SAIT, Suwon, P.O. Box 111 (Korea, Republic of); Kim, Daeil [School of Materials Science and Engineering. University of Ulsan, San 29, Mugeo-Dong, Nam-Gu, Ulsan 680-749 (Korea, Republic of)]. E-mail: dkim84@mail.ulsan.ac.kr

    2007-02-15

    GeSbTe (GST) chalcogenide thin films for the phase-change random access memory (PRAM) were deposited by an atomic layer deposition (ALD) process. New precursors for GST thin films made with an ALD process were synthesized. Among the synthesized precursors, Ge(N(CH{sub 3}){sub 2}){sub 4}, Sb(N(CH{sub 3}){sub 2}){sub 4}, and Te(i-Pr){sub 2} (i-Pr = iso-propyl) were selected. Using the above precursors, GST thin films were deposited using an H{sub 2} plasma-assisted ALD process. Film resistivity abruptly changed after an N{sub 2} annealing process above a temperature of 350 deg. C. Cross-sectional scanning electron microscope (SEM) photographs of the GST films on the patterned substrate with aspect ratio of 7 shows that the step coverage is about 90%.

  3. Development in Zn4Sb-based thermoelectric materials

    DEFF Research Database (Denmark)

    Yin, Hao

    Thermoelectric material, as a functional material which has the dual ability of electrical-thermal energy conversion, has attracted tremendous interests in the last decades, especially against the background of global energy shortage and surging of new materials. The present work focuses...... on the notable Zn4Sb3, with the effort to further the basic understanding of the compound, as well as improve the thermoelectric performance to meet the commercial use. The maximum efficiency of a thermoelectric material is determined by its figure of merit, zT=TS2/ where S is the Seebeck coefficient...... or thermopower,  the electrical conductivity, the thermal conductivity and T the absolute temperature. The best thermoelectrics are heavily doped semiconductors with high thermoelectric power factors and low thermal conductivities, known as “Phonon Glasses Electrical Crystals”. Zn4Sb3 is one such material...

  4. Properties of Doped GaSb Whiskers at Low Temperatures

    Science.gov (United States)

    Khytruk, Igor; Druzhinin, Anatoly; Ostrovskii, Igor; Khoverko, Yuriy; Liakh-Kaguy, Natalia; Rogacki, Krzysztof

    2017-02-01

    Temperature dependencies of GaSb whiskers' resistance doped with Te to concentration of 1.7 × 1018 cm-3 were measured in temperature range 1.5-300 K. At 4.2 K temperature, a sharp drop in the whisker resistance was found. The observed effect is likely connected with the contribution of two processes such as the electron localization in the whiskers and transition in superconducting state at temperature below 4.2 K. The whisker magnetoconductance is considered in the framework of weak antilocalization (WAL) model and connected with subsurface layers of the whiskers. The Shubnikov-de Haas (SdH) oscillatory effect is observed in high-quality n-type GaSb whiskers with tellurium doping concentration near the metal-insulator transition (MIT) for both longitudinal and transverse magnetoresistance.

  5. Heavy-Load Lifting

    DEFF Research Database (Denmark)

    Bloomquist, Kira; Oturai, Peter; Steele, Megan L

    2017-01-01

    PURPOSE: Despite a paucity of evidence, prevention guidelines typically advise avoidance of heavy lifting in an effort to protect against breast cancer-related lymphedema. This study compared acute responses in arm swelling and related symptoms after low- and heavy-load resistance exercise among...... women at risk of lymphedema while receiving adjuvant taxane-based chemotherapy. METHODS: This is a randomized, cross-over equivalence trial. Women receiving adjuvant taxane-based chemotherapy for breast cancer who had undergone axillary lymph node dissection (n=21) participated in low- (60-65% 1...... repetition maximum (RM), two sets of 15-20 repetitions) and heavy-load (85-90% 1RM, three sets of 5-8 repetition) upper-extremity resistance exercise separated by a one-week wash-out period. Swelling was determined by bioimpedance spectroscopy and dual energy x-ray absorptiometry, with breast cancer...

  6. Very heavy dark Skyrmions

    Science.gov (United States)

    Dick, Rainer

    2017-12-01

    A dark sector with a solitonic component provides a means to circumvent the problem of generically low annihilation cross sections of very heavy dark matter particles. At the same time, enhanced annihilation cross sections are necessary for indirect detection of very heavy dark matter components beyond 100 TeV. Non-thermally produced dark matter in this mass range could therefore contribute to the cosmic γ -ray and neutrino flux above 100 TeV, and massive Skyrmions provide an interesting framework for the discussion of these scenarios. Therefore a Higgs portal and a neutrino portal for very heavy Skyrmion dark matter are discussed. The Higgs portal model demonstrates a dark mediator bottleneck, where limitations on particle annihilation cross sections will prevent a signal from the potentially large soliton annihilation cross sections. This problem can be avoided in models where the dark mediator decays. This is illustrated by the neutrino portal for Skyrmion dark matter.

  7. Lattice Thermal Conductivity of the Binary and Ternary Group-IV Alloys Si-Sn, Ge-Sn, and Si-Ge-Sn

    Science.gov (United States)

    Khatami, S. N.; Aksamija, Z.

    2016-07-01

    Efficient thermoelectric (TE) energy conversion requires materials with low thermal conductivity and good electronic properties. Si-Ge alloys, and their nanostructures such as thin films and nanowires, have been extensively studied for TE applications; other group-IV alloys, including those containing Sn, have not been given as much attention as TEs, despite their increasing applications in other areas including optoelectronics. We study the lattice thermal conductivity of binary (Si-Sn and Ge-Sn) and ternary (Si-Ge-Sn) alloys and their thin films in the Boltzmann transport formalisms, including a full phonon dispersion and momentum-dependent boundary-roughness scattering. We show that Si-Sn alloys have the lowest conductivity (3 W /mK ) of all the bulk alloys, more than 2 times lower than Si-Ge, attributed to the larger difference in mass between the two constituents. In addition, we demonstrate that thin films offer an additional reduction in thermal conductivity, reaching around 1 W /mK in 20-nm-thick Si-Sn, Ge-Sn, and ternary Si-Ge-Sn films, which is near the conductivity of amorphous SiO2 . We conclude that group-IV alloys containing Sn have the potential for high-efficiency TE energy conversion.

  8. Crystal Field Parameters and Phase Transitions in ErSb

    DEFF Research Database (Denmark)

    Shapiro, S. M.; Bak, P.

    1975-01-01

    The crystal field levels of the Er ion in a single crystal of ErSb have been measured by inelastic neutron scattering. The crystal field parameters obtained by a least squares fit to the spectra at several temperatures are: B4 = (0·473 ± 0·005) × 10−2°K and B6 = (0·59 ± 0·06) × 10−5°K, which differ...

  9. Heavy exotic molecules

    Science.gov (United States)

    Liu, Yizhuang; Zahed, Ismail

    We briefly review the formation of pion-mediated heavy-light exotic molecules with both charm and bottom, under the general structures of chiral and heavy quark symmetries. The charm isosinglet exotic molecules with JPC = 1++ binds, which we identify as the reported neutral X(3872). The bottom isotriplet exotic with JPC = 1+1 binds, and is identified as a mixed state of the reported charged exotics Zb+(10610) and Zb-(10650). The bound bottom isosinglet molecule with JPC = 1++ is a possible neutral Xb(10532) to be observed.

  10. Valence Band Structure of InAs1-xBix and InSb1-xBix Alloy Semiconductors Calculated Using Valence Band Anticrossing Model

    Directory of Open Access Journals (Sweden)

    D. P. Samajdar

    2014-01-01

    Full Text Available The valence band anticrossing model has been used to calculate the heavy/light hole and spin-orbit split-off energies in InAs1-xBix and InSb1-xBix alloy systems. It is found that both the heavy/light hole, and spin-orbit split E+ levels move upwards in energy with an increase in Bi content in the alloy, whereas the split E− energy for the holes shows a reverse trend. The model is also used to calculate the reduction of band gap energy with an increase in Bi mole fraction. The calculated values of band gap variation agree well with the available experimental data.

  11. Grain boundary engineering with nano-scale InSb producing high performance InxCeyCo4Sb12+z skutterudite thermoelectrics

    Directory of Open Access Journals (Sweden)

    Han Li

    2017-12-01

    Full Text Available Thermoelectric semiconductors based on CoSb3 hold the best promise for recovering industrial or automotive waste heat because of their high efficiency and relatively abundant, lead-free constituent elements. However, higher efficiency is needed before thermoelectrics reach economic viability for widespread use. In this study, n-type InxCeyCo4Sb12+z skutterudites with high thermoelectric performance are produced by combining several phonon scattering mechanisms in a panoscopic synthesis. Using melt spinning followed by spark plasma sintering (MS-SPS, bulk InxCeyCo4Sb12+z alloys are formed with grain boundaries decorated with nano-phase of InSb. The skutterudite matrix has grains on a scale of 100–200 nm and the InSb nano-phase with a typical size of 5–15 nm is evenly dispersed at the grain boundaries of the skutterudite matrix. Coupled with the presence of defects on the Sb sublattice, this multi-scale nanometer structure is exceptionally effective in scattering phonons and, therefore, InxCeyCo4Sb12/InSb nano-composites have very low lattice thermal conductivity and high zT values reaching in excess of 1.5 at 800 K.

  12. Ion irradiation-induced polycrystalline InSb foam

    Science.gov (United States)

    Giulian, R.; Salazar, J. B.; Just, W.; Manzo, D. J.; de Andrade, A. M. H.; Schoffen, J. R.; Bernardi, F.; Baptista, D. L.; Fichtner, P. F. P.

    2017-12-01

    InSb films with various thicknesses were deposited by magnetron sputtering on SiO2/Si substrates and subsequently irradiated with 17 MeV Au+7 ions. The structural and electronic changes induced by ion irradiation were investigated by synchrotron and laboratory based techniques. Ion irradiation of InSb transforms compact films (amorphous and polycrystalline) in open cell solid foams. The initial stages of porosity were investigated by transmission electron microscopy analysis and reveal the porous structure initiates as small spherical voids with approximately 3 nm in diameter. The evolution of porosity was investigated by scanning electron microscopy images, which show that film thickness increases up to 16 times with increasing irradiation fluence. Here we show that amorphous InSb films become polycrystalline foams upon irradiation with 17 MeV Au+7 ions at fluences above 1014 cm‑2. The films attain a zincblende phase, with crystallites randomly oriented, similarly to the polycrystalline structure attained by thermal annealing of unirradiated films.

  13. Production of very neutron-deficient isotopes near sup 1 sup 0 sup 0 Sn via reactions involving light-particle and cluster emission

    CERN Document Server

    La Commara, M; D'Onofrio, A; Gadea, A; Glogowski, M; Jarillo-Herrero, P; Belcari, N; Borcea, R; De Angelis, G; Fahlander, C; aGórska, M; Grawe, H; Hellström, M; Kirchner, R; Rejmund, M; Roca, V; Roeckl, E; Romano, M; Rykaczewski, K; Schmidt, K; Terrasi, F

    2000-01-01

    The production of very neutron-deficient isotopes near sup 1 sup 0 sup 0 Sn has been investigated by using on-line mass separation of evaporation residues produced by heavy-ion induced complete-fusion reactions. We measured the cross sections for sup 9 sup 9 Cd, sup 1 sup 0 sup 0 In, sup 1 sup 0 sup 1 Sn and sup 1 sup 0 sup 2 In via sup 5 sup 8 Ni+ sup 5 sup 8 Ni fusion reactions followed by cluster emission, and via sup 5 sup 8 Ni+ sup 5 sup 0 Cr fusion reactions accompanied by evaporation of protons, neutrons or alpha particles. Both types of reactions yield similar cross sections for the production of exotic nuclei near sup 1 sup 0 sup 0 Sn. The data are discussed in comparison with results obtained from statistical-model calculations.

  14. Structural, electrical and optical properties of annealed Al/Sb multiayer films

    Energy Technology Data Exchange (ETDEWEB)

    He, Jianxiong; Wu, Lili; Feng, Lianghuan; Zheng, Jiagui; Zhang, Jingquan; Li, Wei; Li, Bing; Cai, Yaping [College of Materials Science and Engineering, Sichuan University, Chengdu 610064 (China)

    2011-01-15

    The multilayer Al/Sb thin films were deposited on quartz glass substrates using magnetron sputtering method and annealed at high temperature to obtain AlSb films. The experimental conditions were optimized to obtain the AlSb single phase. XRD measurements indicate that high-temperature annealing is necessary to form AlSb and is helpful to the grain growth of AlSb polycrystalline. The average grain size of AlSb polycrystalline increases obviously with the increase in annealing temperature when higher than 500 C. The electrical measurements show that the prepared AlSb films are p-type semiconductors with the conductivity activation energy of 0.21 and 0.01 eV. The optical band gap for a typical AlSb film is 1.76 eV. The obvious photovoltaic effect has been observed in TCO/CdS/AlSb/ZnTe:Cu/Au devices, which demonstrated the potential of AlSb film as the absorber layer in thin film solar cells. (author)

  15. High capacity, microporous Cu{sub 6}Sn{sub 5}-Sn anodes for Li-Ion batteries.

    Energy Technology Data Exchange (ETDEWEB)

    Trahey, L.; Vaughey, J. T.; Kung, H. H.; Thackeray, M. M. (Chemical Sciences and Engineering Division); ( PSC-USR); (Northwestern Univ.)

    2009-03-16

    Three-dimensional, microporous Cu{sub 6}Sn{sub 5}-Sn architectures were created by electrodeposition of copper and tin onto sintered copper foam substrates and evaluated as anodes for lithium-ion batteries. The electrodes were characterized before and after cycling by X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectrometry. Before cycling, the electrochemically deposited films consisted of a combination of crystalline Cu{sub 6}Sn{sub 5} and Sn, whereas after cycling, the films appeared amorphous to X-rays. When evaluated in coin cells against metallic lithium, the composite Cu{sub 6}Sn{sub 5}-Sn electrodes delivered a reversible capacity of 670 mAh/g, which is significantly greater than the capacity achieved previously from powdered (ballmilled) and thin-film (sputtered) Cu{sub 6}Sn{sub 5} electrodes, typically 200-350 mAh/g.

  16. Phase change characteristics of Sb-rich Ga–Sb–Se materials

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Yegang, E-mail: lvyegang@nbu.edu.cn [Faculty of Information Science and Engineering, Ningbo University, Ningbo 315211 (China); Song, Sannian [State Key Laboratory of Functional Materials for Informatics, Laboratory of Nanotechnology, Shanghai Institute of Micro-system and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Shen, Xiang; Wang, Guoxiang [Faculty of Information Science and Engineering, Ningbo University, Ningbo 315211 (China); Wu, Liangcai; Song, Zhitang; Liu, Bo [State Key Laboratory of Functional Materials for Informatics, Laboratory of Nanotechnology, Shanghai Institute of Micro-system and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Dai, Shixun [Faculty of Information Science and Engineering, Ningbo University, Ningbo 315211 (China)

    2014-02-15

    Highlights: • Phase change behavior of Sb-rich Ga–Sb–Se was studied for phase change memory. • Sb-rich Ga–Sb–Se films possess crystallization temperature higher than 225 °C. • Sb-rich Ga–Sb–Se film has retention ability in excess of 135 °C for 10 years. • Compared with Ge{sub 2}Sb{sub 2}Te{sub 5}, Ga{sub 10}Sb{sub 60}Se{sub 30} has fast crystallization speed. -- Abstract: In this paper, phase change characteristics of Sb-rich Ga–SbSe materials were systematically investigated for ultralong-retention and high-speed phase change memory (PCM). Sb-rich Ga–Sb–Se materials possess crystallization temperature higher than 225 °C and activation energy of crystallization above 3.0 eV, which leads to outstanding data retention ability in excess of 135 °C for 10 years. The film thickness reductions of Ga{sub 9}Sb{sub 71}Se{sub 20} and Ga{sub 10}Sb{sub 60}Se{sub 30} are about 2.6% and 3.8%, respectively, which are smaller than that of Ge{sub 2}Sb{sub 2}Te{sub 5} during the amorphous-to-crystalline phase transition. Ga{sub 10}Sb{sub 60}Se{sub 30} film exhibits a reversible phase change under irradiation of optical pulse. The fast crystallization is due to the precipitation of Sb crystallites acting as a template to accelerate the crystallization.

  17. Characterisation of Ga1-xInxSb quantum wells (x~0.3 grown on GaAs using AlGaSb interface misfit buffer

    Directory of Open Access Journals (Sweden)

    Jonathan P. Hayton

    2015-05-01

    Full Text Available GaInSb multiple quantum wells (MQW grown on GaAs using an AlGaSb interface misfit (IMF metamorphic buffer layer technique exhibit superior infrared photoluminescence (PL at room temperature compared with MQW grown directly on GaSb. PL emission was obtained in the range from 1.7 μm (4 K to 1.9 μm (300 K from Ga1-xInxSb samples containing five compressively strained QW with In content x~0.3. Structural and optical characterisation confirms that the AlGaSb IMF growth technique is promising for the development of photonic devices operating at extended wavelengths based on GaAs substrates.

  18. Short-wave infrared barriode detectors using InGaAsSb absorption material lattice matched to GaSb

    Energy Technology Data Exchange (ETDEWEB)

    Craig, A. P.; Percy, B.; Marshall, A. R. J. [Physics Department, Lancaster University, Lancaster LA1 4YB (United Kingdom); Jain, M. [Amethyst Research Ltd., Kelvin Campus, West of Scotland Science Park, Glasgow G20 0SP (United Kingdom); Wicks, G.; Hossain, K. [Amethyst Research, Inc., 123 Case Circle, Ardmore, Oklahoma 73401 (United States); Golding, T. [Amethyst Research Ltd., Kelvin Campus, West of Scotland Science Park, Glasgow G20 0SP (United Kingdom); Amethyst Research, Inc., 123 Case Circle, Ardmore, Oklahoma 73401 (United States); McEwan, K.; Howle, C. [Defence Science and Technology Laboratory, Porton Down, Salisbury, Wiltshire SP4 0JQ (United Kingdom)

    2015-05-18

    Short-wave infrared barriode detectors were grown by molecular beam epitaxy. An absorption layer composition of In{sub 0.28}Ga{sub 0.72}As{sub 0.25}Sb{sub 0.75} allowed for lattice matching to GaSb and cut-off wavelengths of 2.9 μm at 250 K and 3.0 μm at room temperature. Arrhenius plots of the dark current density showed diffusion limited dark currents approaching those expected for optimized HgCdTe-based detectors. Specific detectivity figures of around 7×10{sup 10} Jones and 1×10{sup 10} Jones were calculated, for 240 K and room temperature, respectively. Significantly, these devices could support focal plane arrays working at higher operating temperatures.

  19. New Insights into the Origins of Sb-Induced Effects on Self-Catalyzed GaAsSb Nanowire Arrays

    DEFF Research Database (Denmark)

    Ren, Dingding; Dheeraj, Dasa L.; Jin, Chengjun

    2016-01-01

    Tertiary semiconductor nanowire arrays enable scalable fabrication of nano-optoelectronic devices with tunable bandgap. However, the lack of insight into the effects of the incorporation of Vy element results in lack of control on the growth of ternary III-V1-yVy nanowires and hinders the develop......Tertiary semiconductor nanowire arrays enable scalable fabrication of nano-optoelectronic devices with tunable bandgap. However, the lack of insight into the effects of the incorporation of Vy element results in lack of control on the growth of ternary III-V1-yVy nanowires and hinders...... the development of high-performance nanowire devices based on such ternaries. Here, we report on the origins of Sb-induced effects affecting the morphology and crystal structure of self-catalyzed GaAsSb nanowire arrays. The, nanowire growth by molecular beam epitaxy is changed both kinetically...

  20. SnO{sub 2} thin films grown by atomic layer deposition using a novel Sn precursor

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Min-Jung [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul, 136-791 (Korea, Republic of); Department of Materials Science and Engineering, Yonsei University, Seoul, 120-749 (Korea, Republic of); Cho, Cheol Jin [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul, 136-791 (Korea, Republic of); Department of Materials Science and Engineering, Seoul National University, Seoul, 151-744 (Korea, Republic of); Kim, Kwang-Chon; Pyeon, Jung Joon [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul, 136-791 (Korea, Republic of); Park, Hyung-Ho [Department of Materials Science and Engineering, Yonsei University, Seoul, 120-749 (Korea, Republic of); Kim, Hyo-Suk; Han, Jeong Hwan; Kim, Chang Gyoun; Chung, Taek-Mo [Division of Advanced Materials, Korea Research Institute of Chemical Technology (KRICT), Daejeon, 305-600 (Korea, Republic of); Park, Tae Joo [Department of Materials Science and Engineering, Hanyang University, Ansan, 426-791 (Korea, Republic of); Kwon, Beomjin [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul, 136-791 (Korea, Republic of); Jeong, Doo Seok; Baek, Seung-Hyub [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul, 136-791 (Korea, Republic of); Department of Nanomaterials, Korea University of Science and Technology, Daejeon, 305-333 (Korea, Republic of); Kang, Chong-Yun; Kim, Jin-Sang [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul, 136-791 (Korea, Republic of); Kim, Seong Keun, E-mail: s.k.kim@kist.re.kr [Electronic Materials Research Center, Korea Institute of Science and Technology, Seoul, 136-791 (Korea, Republic of); Department of Nanomaterials, Korea University of Science and Technology, Daejeon, 305-333 (Korea, Republic of)

    2014-11-30

    Highlights: • We developed a new ALD process for SnO{sub 2} films using dimethylamino-2-methyl-2-propoxy-tin(II) as a novel Sn precursor. • The SnO{sub 2} films grown from Sn(dmamp){sub 2} has negligible impurity contents. • Sn ions in the films had a single binding state corresponding to Sn{sup 4+} in SnO{sub 2}. - Abstract: SnO{sub 2} thin films were grown by atomic layer deposition (ALD) with dimethylamino-2-methyl-2-propoxy-tin(II) (Sn(dmamp){sub 2}) and O{sub 3} in a temperature range of 100–230 °C. The ALD window was found to be in the range of 100–200 °C. The growth per cycle of the films in the ALD window increased with temperature in the range from 0.018 to 0.042 nm/cycle. Above 230 °C, the self-limiting behavior which is a unique characteristic of ALD, was not observed in the growth because of the thermal decomposition of the Sn(dmamp){sub 2} precursor. The SnO{sub 2} films were amorphous in the ALD window and exhibited quite a smooth surface. Sn ions in all films had a single binding state corresponding to Sn{sup 4+} in SnO{sub 2}. The concentration of carbon and nitrogen in the all SnO{sub 2} films was below the detection limit of the auger electron spectroscopy technique and a very small amount of carbon, nitrogen, and hydrogen was detected by secondary ions mass spectroscopy only. The impurity contents decreased with increasing the growth temperature. This is consistent with the increase in the density of the SnO{sub 2} films with respect to the growth temperature. The ALD process with Sn(dmamp){sub 2} and O{sub 3} shows excellent conformality on a hole structure with an aspect ratio of ∼9. This demonstrates that the ALD process with Sn(dmamp){sub 2} and O{sub 3} is promising for growth of robust and highly pure SnO{sub 2} films.

  1. High-Reliability Low-Ag-Content Sn-Ag-Cu Solder Joints for Electronics Applications

    Science.gov (United States)

    Shnawah, Dhafer Abdulameer; Said, Suhana Binti Mohd; Sabri, Mohd Faizul Mohd; Badruddin, Irfan Anjum; Che, Fa Xing

    2012-09-01

    Sn-Ag-Cu (SAC) alloy is currently recognized as the standard lead-free solder alloy for packaging of interconnects in the electronics industry, and high- Ag-content SAC alloys are the most popular choice. However, this choice has been encumbered by the fragility of the solder joints that has been observed in drop testing as well as the high cost of the Ag itself. Therefore, low-Ag-content SAC alloy was considered as a solution for both issues. However, this approach may compromise the thermal-cycling performance of the solders. Therefore, to enhance the thermal-cycling reliability of low-Ag-content SAC alloys without sacrificing their drop-impact performance, alloying elements such as Mn, Ce, Ti, Bi, In, Sb, Ni, Zn, Al, Fe, and Co were selected as additions to these alloys. However, research reports related to these modified SAC alloys are limited. To address this paucity, the present study reviews the effect of these minor alloying elements on the solder joint reliability of low-Ag-content SAC alloys in terms of thermal cycling and drop impact. Addition of Mn, Ce, Bi, and Ni to low-Ag-content SAC solder effectively improves the thermal-cycling reliability of joints without sacrificing the drop-impact performance. Taking into consideration the improvement in the bulk alloy microstructure and mechanical properties, wetting properties, and growth suppression of the interface intermetallic compound (IMC) layers, addition of Ti, In, Sb, Zn, Al, Fe, and Co to low-Ag-content SAC solder has the potential to improve the thermal-cycling reliability of joints without sacrificing the drop-impact performance. Consequently, further investigations of both thermal-cycling and drop reliability of these modified solder joints must be carried out in future work.

  2. Optimization of metamorphic buffers for MBE growth of high quality AlInSb/InSb quantum structures: Suppression of hillock formation

    Science.gov (United States)

    Shi, Y.; Gosselink, D.; Gharavi, K.; Baugh, J.; Wasilewski, Z. R.

    2017-11-01

    The optimization of metamorphic buffers for InSb/AlInSb QWs grown on GaAs (0 0 1) substrates is presented. With increasing surface offcut angle towards [ 1 1 bar 0 ] direction, the interaction of spiral growth around threading dislocations (TDs) with the offcut-induced atomic steps leads to a gradual change in the morphology of the AlSb buffer from one dominated by hillocks to that exhibiting near-parallel steps, and finally to a surface with increasing number of localized depressions. With the growth conditions used, the smoothest AlSb surface morphology was obtained for the offcut angles range of 0.8-1.3°. On substrates with 0° offcut, subsequent 3 repeats of Al0.24In0.76 Sb/Al0.12In0.88 Sb interlayers reduces the TD density of AlSb buffer by a factor of 10, while 70 times reduction in the surface density of TD-related hillocks is observed. The remaining hillocks have rectangular footprint and small facet angles with respect to GaAs (0 0 1) surface: 0.4° towards [ 1 1 bar 0 ] direction and 0.7° towards [1 1 0] direction. Their triangular-shaped sidewalls with regularly spaced atomic steps show occasional extra step insertion sites, characteristic of TD outcrops. Many of the observed sidewalls are dislocation free and offer atomically smooth areas of up to 1 μm2, already suitable for high-quality InSb growth and subsequent top-down fabrication of InSb nanowires. It is proposed that the sidewalls of the remaining hillocks offer local vicinal surfaces with atomic step density optimal for suppression of TD-induced spiral growth, thus providing the important information on the exact substrate offcut needed to achieve large hillock-free and atomically smooth areas on AlInSb metamorphic buffers.

  3. Bioaccumulation of Heavy Metals

    African Journals Online (AJOL)

    komla

    acute toxicity and sublethal chronic action the devastating effects that the accumulation - ... surrounding waters. The results showed a programmes of heavy metals in aquatic strong and positive correlation (r = 0.97) ecosystems. between amounts of metals in the aquatic ...... Chemical composition of agricultural waste.

  4. Heavy chain only antibodies

    DEFF Research Database (Denmark)

    Moghimi, Seyed Moein; Rahbarizadeh, Fatemeh; Ahmadvand, Davoud

    2013-01-01

    Unlike conventional antibodies, heavy chain only antibodies derived from camel contain a single variable domain (VHH) and two constant domains (CH2 and CH3). Cloned and isolated VHHs possess unique properties that enable them to excel conventional therapeutic antibodies and their smaller antigen...

  5. Heavy liquid bubble chamber

    CERN Multimedia

    CERN PhotoLab

    1965-01-01

    The CERN Heavy liquid bubble chamber being installed in the north experimental hall at the PS. On the left, the 1180 litre body; in the centre the magnet, which can produce a field of 26 800 gauss; on the right the expansion mechanism.

  6. Magnetic Field-Induced Reverse Martensitic Transformation and Thermal Transformation Arrest Phenomenon of Ni41Co9Mn39Sb11 Alloy

    Directory of Open Access Journals (Sweden)

    Rie Y. Umetsu

    2014-12-01

    Full Text Available In order to investigate behavior of magnetic field-induced reverse martensitic transformation for Ni-Co-Mn-Sb, magnetization experiments up to a static magnetic field of 18 T and a pulsed magnetic field of 40 T were carried out. In the thermomagnetization curves for Ni41Co9Mn39Sb11 alloy, the equilibrium transformation temperature T0 was observed to decrease with increasing applied magnetic field, μ0H, at a rate of dT0/dμ0H = 4.6 K/T. The estimated value of entropy change evaluated from the Clausius-Clapeyron relation was about 14.1 J/(K·kg, which was in good agreement with the value obtained by differential scanning calorimetric measurements. For the isothermal magnetization curves, metamagnetic behavior associated with the magnetic field-induced martensitic transformation was observed. The equilibrium magnetic field, μ0H0 = (μ0HAf + μ0HMs/2, of the martensitic transformation tended to be saturated at lower temperature; that is, transformation arrest phenomenon was confirmed for the Ni-Co-Mn-Sb system, analogous with the Ni(Co-Mn-Z (Z = In, Sn, Ga, Al alloys. Temperature dependence of the magnetic field hysteresis, μ0Hhys = μ0HAf − μ0HMs, was analyzed based on the model for the plastic deformation introduced by the dislocations. The behavior can be explained by the model and the difference of the sweeping rate of the applied magnetic field was well reflected by the experimental results.

  7. The dipole response of {sup 132}Sn

    Energy Technology Data Exchange (ETDEWEB)

    Schrock, Philipp; Aumann, Thomas; Johansen, Jacob; Schindler, Fabia [IKP, TU Darmstadt (Germany); Boretzky, Konstanze [GSI Helmholtzzentrum (Germany); Rossi, Dominic [Michigan State University (United States); Collaboration: R3B-Collaboration

    2015-07-01

    The Isovector Giant Dipole Resonance (IVGDR) is a well-known collective excitation in which all protons oscillate against all neutrons of a nucleus. In neutron-rich nuclei an additional low-lying dipole excitation occurs, often denoted as Pygmy Dipole Resonance (PDR). To study the PDR in exotic Sn-isotopes, an experiment has been successfully performed with the upgraded R{sup 3}B-LAND setup at GSI. The complete-kinematics measurement of all reaction participants allows for the reconstuction of the excitation energy and, hence, the extraction of the dipole strength. Presented are the main features of the experiment, the analysis concept and the current status of the analysis of the dipole response of the doubly-magic isotope {sup 132}Sn.

  8. Optical parameters of diode lasers based on an InAsSb/InAsSbP heterostructure

    Energy Technology Data Exchange (ETDEWEB)

    Astakhova, A. P. [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation); Bez' yazychnaya, T. V. [National Academy of Sciences of Belarus, Stepanov Institute of Physics (Belarus); Burov, L. I.; Gorbatsevich, A. S.; Ryabtsev, A. G. [Belarussian State University (Belarus); Ryabtsev, G. I. [National Academy of Sciences of Belarus, Stepanov Institute of Physics (Belarus); Shchemelev, M. A. [Belarussian State University (Belarus); Yakovlev, Yu. P., E-mail: Yak@iropt1.ioffe.ru [Russian Academy of Sciences, Ioffe Physicotechnical Institute (Russian Federation)

    2008-02-15

    The rates of radiative recombination (including transitions induced by enhanced luminescence) and nonradiative recombination, internal quantum yield of luminescence, and the matrix element for band-to-band optical transitions were determined for the first time for InAsSb/InAsSbP diode lasers oscillating at wavelengths of 3.1-3.2 {mu}m. It is established that the contribution of nonradiative recombination to the lasing threshold can be as large as 97%. The internal quantum yield of luminescence for the InAs{sub 0.97}Sb{sub 0.03} compound is no higher than 3%. Most likely, the nonradiative channel is formed with involvement of Auger recombination with the constant C = 4.2 Multiplication-Sign 10{sup -38} m{sup 6}s{sup -1} (T = 77 K). The studied samples of lasers feature relatively low optical losses {rho} = 900 m{sup -1} and internal quantum efficiency of emission at the level of 0.6. The spontaneous lifetime of nonequilibrium charge carriers as determined from the radiative-recombination rate is equal to 6 Multiplication-Sign 10{sup -8} s, which is consistent with known published data.

  9. Crystallographic Orientation Effect on Electromigration in Ni-Sn Microbump

    Science.gov (United States)

    Huang, Yi-Ting; Chen, Chih-Hao; Chakroborty, Subhendu; Wu, Albert T.

    2017-09-01

    This article addresses the reliability challenges regarding electromigration in developing three-dimensional integrated circuits (3D-ICs). The line-type sandwich structure of Ni/Sn3.5Ag(15 μm)/Ni was used to simulate microbumps to examine the reliability of electromigration in 3D-IC technology. The solder strip of Ni/Sn3.5Ag(15 μm)/Ni was stressed with a current density of 1.0 × 104 A/cm2 at 150°C. The current stressing enhanced the reaction between the solder and Ni to form Ni3Sn4, which occupied the entire joint and transformed into a Ni/Ni3Sn4/Ni structure when the solder was completely consumed. Electron backscatter diffraction was used to analyze the crystallographic characteristics of Sn and Ni3Sn4 as related to the electromigration effect. The results indicated that the crystallographic orientation of Sn plays a significant role in the Ni/Sn3.5Ag/Ni, whereas the orientation of Ni3Sn4 is the dominant factor of diffusion behavior in the Ni/Ni3Sn4/Ni.

  10. Nonthermal emission of SN 1987A

    Science.gov (United States)

    Berezhko, Evgeny; Ksenofontov, Leonid; Voelk, Heinrich

    A nonlinear kinetic theory of cosmic-ray acceleration in supernova remnants is employed to investigate the properties of the remnant SN 1987A. Recent observational data in radio and X-ray is used to constrain a set of model parameters. The spectrum of gamma-ray emission and its behavior in time is calculated and compared with sensitivities of the modern ground-based gamma-ray experiments.

  11. On Mossbauer dynamics in Nb3Sn

    Indian Academy of Sciences (India)

    Before the advent of high temperature oxide superconductivity, several intermetallic com- pounds possessing A15 crystal structure [1] have been known to be good superconductors; namely V3Si (Мc=17.1 K), V3Ga (Мc=16.8 K), Nb3Sn (Мc=18 K), Nb3Al (Мc=18.5 K) and Nb3Alo75 Geo75 (Мc=20 K). A15 group of ...

  12. A review and prospects for Nb3Sn superconductor development

    Science.gov (United States)

    Xu, Xingchen

    2017-09-01

    Nb3Sn superconductors have significant applications in constructing high-field (>10 T) magnets. This article briefly reviews development of Nb3Sn superconductor and proposes prospects for further improvement. It is shown that significant improvement of critical current density (J c) is needed for future accelerator magnets. After a brief review of the development of Nb3Sn superconductors, the factors controlling J c are summarized and correlated with their microstructure and chemistry. The non-matrix J c of Nb3Sn conductors is mainly determined by three factors: the fraction of current-carrying Nb3Sn phase in the non-matrix area, the upper critical field B c2, and the flux line pinning capacity. Then prospects to improve the three factors are discussed respectively. An analytic model was developed to show how the ratios of precursors determine the phase fractions after heat treatment, based on which it is predicted that the limit of current-carrying Nb3Sn fraction in subelements is ∼65%. Then, since B c2 is largely determined by the Nb3Sn stoichiometry, a thermodynamic/kinetic theory is presented to show what essentially determines the Sn content of Nb3Sn conductors. This theory explains the influences of Sn sources and Ti addition on stoichiometry and growth rate of Nb3Sn layers. Next, to improve flux pinning, previous efforts in this community to introduce additional pinning centers to Nb3Sn wires are reviewed, and an internal oxidation technique is described. Finally, prospects for further improvement of non-matrix J c of Nb3Sn conductors are discussed, and it is seen that the only opportunity for further significantly improving J c lies in improving flux pinning.

  13. VERY LATE PHOTOMETRY OF SN 2011fe

    Energy Technology Data Exchange (ETDEWEB)

    Kerzendorf, W. E. [Department of Astronomy and Astrophysics, University of Toronto, 50 Saint George Street, Toronto, ON M5S 3H4 (Canada); Taubenberger, S.; Seitenzahl, I. R.; Ruiter, A. J., E-mail: wkerzendorf@gmail.com [Max-Planck-Institut für Astrophysik, Karl-Schwarzschild-Straße 1, D-85748 Garching (Germany)

    2014-12-01

    The Type Ia supernova SN 2011fe is one of the closest supernovae of the past decades. Due to its proximity and low dust extinction, this object provides a very rare opportunity to study the extremely late time evolution (>900 days) of thermonuclear supernovae. In this Letter, we present our photometric data of SN 2011fe taken at an unprecedented late epoch of ≈930 days with GMOS-N mounted on the Gemini North telescope (g = 23.43 ± 0.28, r = 24.14 ± 0.14, i = 23.91 ± 0.18, and z = 23.90 ± 0.17) to study the energy production and retention in the ejecta of SN 2011fe. Together with previous measurements by other groups, our result suggests that the optical supernova light curve can still be explained by the full thermalization of the decay positrons of {sup 56}Co. This is in spite of theoretical predicted effects (e.g., infrared catastrophe, positron escape, and dust) that advocate a substantial energy redistribution and/or loss via various processes that result in a more rapid dimming at these very late epochs.

  14. Thermoelectric properties of SnSe compound

    Energy Technology Data Exchange (ETDEWEB)

    Guan, Xinhong [State Key Laboratory of Information Photonics and Optical Communications, Ministry of Education, Beijing University of Posts and Telecommunications, P.O. Box 72, Beijing 100876 (China); Lu, Pengfei, E-mail: photon@bupt.edu.cn [State Key Laboratory of Information Photonics and Optical Communications, Ministry of Education, Beijing University of Posts and Telecommunications, P.O. Box 72, Beijing 100876 (China); Wu, Liyuan; Han, Lihong [State Key Laboratory of Information Photonics and Optical Communications, Ministry of Education, Beijing University of Posts and Telecommunications, P.O. Box 72, Beijing 100876 (China); Liu, Gang [School of Electronic Engineering, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Song, Yuxin [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Wang, Shumin [State Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050 (China); Photonics Laboratory, Department of Microtechnology and Nanoscience, Chalmers University of Technology, 41296 Gothenburg (Sweden)

    2015-09-15

    Highlights: • The electronic and thermoelectric properties of SnSe bulk material are studied. • The ZT can reach as high as 1.87 along yy and 1.6 along zz direction at 800k. • SnSe is an indirect-band material, and SOC has little effect on the band structure. • The high ZT can be attributed to the intrinsically ultralow thermal conductivity. - Abstract: A first-principles study and Boltzmann transport theory have been performed to evaluate the electronic structure and thermoelectric properties of SnSe compound. The energy band structure and density of states are studied in detail. The electronic transport coefficients are then calculated as a function of chemical potential or temperature within the assumption of the constant relaxation time. The figure of merit ZT is obtained with the use of calculated thermoelectric properties and can reach as high as 1.87 along yy and 1.6 along zz direction at 800 K. Our theoretical result agrees well with previous experimental data.

  15. A large deviation principle for Minkowski sums of heavy-tailed random compact convex sets with finite expectation

    DEFF Research Database (Denmark)

    Mikosch, Thomas Valentin; Pawlas, Zbynek; Samorodnitsky, Gennady

    2011-01-01

    We prove large deviation results for Minkowski sums Sn of independent and identically distributed random compact sets where we assume that the summands have a regularly varying distribution and finite expectation. The main focus is on random convex compact sets. The results confirm the heavy......-tailed large deviation heuristics: `large' values of the sum are essentially due to the `largest' summand. These results extend those in Mikosch, Pawlas and Samorodnitsky (2011) for generally nonconvex sets, where we assumed that the normalization of Sn grows faster than n....

  16. Influence of electrode microstructure on the reactivity of Cu{sub 2}Sb with lithium

    Energy Technology Data Exchange (ETDEWEB)

    Morcrette, M.; Larcher, D.; Tarascon, J.M. [Laboratoire de Reactivite et Chimie des Solides, Universite de Picardie Jules Verne, CNRS-UMR 6007, 33 rue Saint Leu, 80039 Amiens Cedex (France); Edstroem, K. [Department of Materials Chemistry, Aangstroem Laboratory, Uppsala University, SE-751 21 Uppsala (Sweden); Vaughey, J.T.; Thackeray, M.M. [Electrochemical Technology Program, Chemical Technology Division, Argonne National Laboratory, Argonne, IL 60439 (United States)

    2007-05-05

    The reactivity of lithium with Cu{sub 2}Sb was recently described to be governed by displacement reactions of Cu similar to those occurring in Cu{sub 2.33}V{sub 4}O{sub 11}. In order to complement the earlier work of Fransson et al., we have revisited the electrochemical reactivity of Cu{sub 2}Sb with Li. Through a different arsenal of characterization techniques, we have emphasized the role of the particle size, electrode preparation and temperature on the reversibility of the electrochemical reaction. We have demonstrated that the structural reversibility of the Cu{sub 2}Sb electrode can be obtained in two special cases: (1) when the particle size of Cu{sub 2}Sb is small and when the powders are ball milled with carbon and (2) when Li{sub 2}CuSb is used as the starting material and some Sb is lost from the electrode during charge. (author)

  17. Comparative analysis of hole transport in compressively strained InSb and Ge quantum well heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Agrawal, Ashish; Barth, Michael; Madan, Himanshu; Datta, Suman [Department of Electrical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 (United States); Lee, Yi-Jing; Lin, You-Ru; Wu, Cheng-Hsien; Ko, Chih-Hsin; Wann, Clement H. [Taiwan Semiconductor Manufacturing Company, Hsinchu 30078, Taiwan (China); Loubychev, Dmitri; Liu, Amy; Fastenau, Joel [IQE, Inc., Bethlehem, Pennsylvania 18015 (United States); Lindemuth, Jeff [Lake Shore Cryotronics, Westerville, Ohio 43082 (United States)

    2014-08-04

    Compressively strained InSb (s-InSb) and Ge (s-Ge) quantum well heterostructures are experimentally studied, with emphasis on understanding and comparing hole transport in these two-dimensional confined heterostructures. Magnetotransport measurements and bandstructure calculations indicate 2.5× lower effective mass for s-InSb compared to s-Ge quantum well at 1.9 × 10{sup 12} cm{sup –2}. Advantage of strain-induced m* reduction is negated by higher phonon scattering, degrading hole transport at room temperature in s-InSb quantum well compared to s-Ge heterostructure. Consequently, effective injection velocity is superior in s-Ge compared to s-InSb. These results suggest s-Ge quantum well heterostructure is more favorable and promising p-channel candidate compared to s-InSb for future technology node.

  18. A facile inexpensive route for SnS thin film solar cells with SnS{sub 2} buffer

    Energy Technology Data Exchange (ETDEWEB)

    Gedi, Sreedevi [School of Chemical Engineering, Yeungnam University, 280Daehak-ro, Gyeongsan 712-749, Republic of Korea (Korea, Republic of); Solar Photovoltaic Laboratory, Department of Physics, Sri Venkateswasra University, Tirupati 517 502 (India); Minna Reddy, Vasudeva Reddy, E-mail: drmvasudr9@gmail.com [School of Chemical Engineering, Yeungnam University, 280Daehak-ro, Gyeongsan 712-749, Republic of Korea (Korea, Republic of); Solar Photovoltaic Laboratory, Department of Physics, Sri Venkateswasra University, Tirupati 517 502 (India); Pejjai, Babu [School of Chemical Engineering, Yeungnam University, 280Daehak-ro, Gyeongsan 712-749, Republic of Korea (Korea, Republic of); Solar Photovoltaic Laboratory, Department of Physics, Sri Venkateswasra University, Tirupati 517 502 (India); Jeon, Chan-Wook [School of Chemical Engineering, Yeungnam University, 280Daehak-ro, Gyeongsan 712-749, Republic of Korea (Korea, Republic of); Park, Chinho, E-mail: chpark@ynu.ac.kr [School of Chemical Engineering, Yeungnam University, 280Daehak-ro, Gyeongsan 712-749, Republic of Korea (Korea, Republic of); Ramakrishna Reddy, K.T., E-mail: ktrkreddy@gmail.com [Solar Photovoltaic Laboratory, Department of Physics, Sri Venkateswasra University, Tirupati 517 502 (India)

    2016-05-30

    Graphical abstract: PYS spectra of SnS/SnS{sub 2} interface and the related band diagram. - Highlights: • A low cost SnS solar cell is developed using chemical bath deposition. • We found E{sub I} & χ of SnS (5.3 eV & 4.0 eV) and SnS{sub 2} (6.9 eV & 4.1 eV) films from PYS. • Band offsets of 0.1 eV (E{sub c}) and 1.6 eV (E{sub v}) are estimated for SnS/SnS{sub 2} junction. • SnS based solar cell showed a conversion efficiency of 0.51%. - Abstract: Environment-friendly SnS based thin film solar cells with SnS{sub 2} as buffer layer were successfully fabricated from a facile inexpensive route, chemical bath deposition (CBD). Layer studies revealed that as-grown SnS and SnS{sub 2} films were polycrystalline; (1 1 1)/(0 0 1) peaks as the preferred orientation; 1.3 eV/2.8 eV as optical band gaps; and showed homogeneous microstructure with densely packed grains respectively. Ionization energy and electron affinity values were found by applying photoemission yield spectroscopy (PYS) to the CBD deposited SnS and SnS{sub 2} films for the first time. These values obtained as 5.3 eV and 4.0 eV for SnS films; 6.9 eV and 4.1 eV for SnS{sub 2} films. The band alignment of SnS/SnS{sub 2} junction showed TYPE-II heterostructure. The estimated conduction and valance band offsets were 0.1 eV and 1.6 eV respectively. The current density–voltage (J–V) measurements of the cell showed open circuit voltage (V{sub oc}) of 0.12 V, short circuit current density (J{sub sc}) of 10.87 mA cm{sup −2}, fill factor (FF) of 39% and conversion efficiency of 0.51%.

  19. Effects of Ge substitution on morphology and electrical properties of Cu2Sn(S,Se)3 bulk at a fixed Se/[Se+S] composition

    Science.gov (United States)

    Alemu Zeleke, Misganaw; Kuo, Dong-Hau; Ahmed Zelekew, Osman; Daniel Saragih, Albert

    2017-11-01

    Ge-substituted Cu2Sn(S,Se)3 bulks with Cu2(Sn1-xGex)(S,Se)3 formula at x = 0, 0.25, 0.50, 0.75, and 1.0 were synthesized by reactive liquid phase sintering, where the heating process was held at 200 °C for 20 min before reaching the sintering temperature of 600 °C for 30 min. In the presence of volatile Sb2S3 sintering aid, the effects on densification, grain boundary, crystalline size, and electrical properties of Ge-substitution were investigated. Cu2(Sn1-xGex)(S,Se)3 showed p-type behavior for all x values. It was found that the mobility was increased sharply and carrier concentration was decreased rapidly as the x-value was increased. The electrical conductivities were found to be 14.0, 22.7, 36.8, 126, and 153 S/cm at x = 0, 0.25, 0.50, 0.75, and 1.0, respectively. X-ray diffraction (XRD) peaks were shifted to the higher angle and band gaps increased upon successive increasing of the Ge/[Ge+Sn] fraction being 1.19, 1.21, 1.22, 1.24, and 1.26 eV at x = 0, 0.25, 0.50, 0.75, and 1.0, respectively. The studies of Ge-x-CTSSe bulks were based on GeSn defects and supported by the data of morphological, structural, electrical, and optical properties.

  20. High Quality InAs/InSb nanowire heterostructrues grown by metalorganic vapour phase epitaxy

    DEFF Research Database (Denmark)

    Caroff, Philippe; Wagner, Jakob Birkedal; Dick, Kimberly A.

    2008-01-01

    Growth and structural analysis of epitaxial InAs/InSb nanowire heterostructures are demonstrated for the first time. InSb segments are found to be perfect crystals, free of stacking faults or other major defects, and have a sharp interface with InAs (see image). After growth the seed particle...... is a single crystal nearly lattice matched to the nanowire. InSb segments are n-type and form ohmic contacts with Ni/Au electrodes....