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Sample records for bismuth emitting liquid

  1. Liquid Bismuth Propellant Flow Sensor

    Science.gov (United States)

    Polzin, Kurt A.; Stanojev, B. J.; Korman, V.

    2007-01-01

    Quantifying the propellant mass flow rate in liquid bismuth-fed electric propulsion systems has two challenging facets. First, the flow sensors must be capable of providing a resolvable measurement at propellant mass flow rates on the order of 10 mg/see with and uncertainty of less that 5%. The second challenge has to do with the fact that the materials from which the flow sensors are fabricated must be capable of resisting any of the corrosive effects associated with the high-temperature propellant. The measurement itself is necessary in order to properly assess the performance (thrust efficiency, Isp) of thruster systems in the laboratory environment. The hotspot sensor[I] has been designed to provide the bismuth propellant mass flow rate measurement. In the hotspot sensor, a pulse of thermal energy (derived from a current pulse and associated joule heating) is applied near the inlet of the sensor. The flow is "tagged" with a thermal feature that is convected downstream by the flowing liquid metal. Downstream, a temperature measurement is performed to detect a "ripple" in the local temperature associated with the passing "hotspot" in the propellant. By measuring the time between the upstream generation and downstream detection of the thermal feature, the flow speed can be calculated using a "time of flight" analysis. In addition, the system can be calibrated by measuring the accumulated mass exiting the system as a-function of time and correlating this with the time it takes the hotspot to convect through the sensor. The primary advantage of this technique is that it doesn't depend on an absolute measurement of temperature but, instead, relies on the observation of thermal features. This makes the technique insensitive to other externally generated thermal fluctuations. In this paper, we describe experiments performed using the hotspot flow sensor aimed at quantifying the resolution of the sensor technology. Propellant is expelled onto an electronic scale to

  2. REMOVAL OF CERTAIN FISSION PRODUCT METALS FROM LIQUID BISMUTH COMPOSITIONS

    Science.gov (United States)

    Dwyer, O.E.; Howe, H.E.; Avrutik, E.R.

    1959-11-24

    A method is described for purifying a solution of urarium in liquid bismuth containing at least one metal from the group consisting of selenium, tellurium, palladium, ruthenium, rhodium, niobium, and zirconium. The solution is contacted with zinc in an inert atmosphere to form a homogeneous melt, a solid zinc phase is formed, and the zinc phase containing the metal is separated from the melt.

  3. Compact and Integrated Liquid Bismuth Propellant Feed System

    Science.gov (United States)

    Polzin, Kurt A.; Stanojev, Boris; Korman, Valentin; Gross, Jeffrey T.

    2007-01-01

    Operation of Hall thrusters with bismuth propellant has been shown to be a promising path toward high-power, high-performance, long-lifetime electric propulsion for spaceflight missions [1]. There has been considerable effort in the past three years aimed at resuscitating this promising technology and validating earlier experimental results indicating the advantages of a bismuth-fed Hall thruster. A critical element of the present effort is the precise metering of propellant to the thruster, since performance cannot be accurately assessed without an accurate accounting of mass flow rate. Earlier work used a pre./post-test propellant weighing scheme that did not provide any real-time measurement of mass flow rate while the thruster was firing, and makes subsequent performance calculations difficult. The motivation of the present work is to develop a precision liquid bismuth Propellant Management System (PMS) that provides hot, molten bismuth to the thruster while simultaneously monitoring in real-time the propellant mass flow rate. The system is a derivative of our previous propellant feed system [2], but the present system represents a more compact design. In addition, all control electronics are integrated into a single unit and designed to reside on a thrust stand and operate in the relevant vacuum environment where the thruster is operating, significantly increasing the present technology readiness level of liquid metal propellant feed systems. The design of various critical components in a bismuth PMS are described. These include the bismuth reservoir and pressurization system, 'hotspot' flow sensor, power system and integrated control system. Particular emphasis is given to selection of the electronics employed in this system and the methods that were used to isolate the power and control systems from the high-temperature portions of the feed system and thruster. Open loop calibration test results from the 'hotspot' flow sensor are reported, and results of

  4. Compatibility of structural materials with liquid bismuth, lead, and mercury

    Energy Technology Data Exchange (ETDEWEB)

    Weeks, J.R. [Brookhaven National Lab., Upton, NY (United States)

    1996-06-01

    During the 1950s and 1960s, a substantial program existed at Brookhaven National Laboratory as part of the Liquid Metal Fuel reactor program on the compatibility of bismuth, lead, and their alloys with structural materials. Subsequently, compatibility investigations of mercury with structural materials were performed in support of development of Rankine cycle mercury turbines for nuclear applications. The present talk will review present understanding of the corrosion/mass-transfer reactions of structural materials with these liquid metal coolants. Topics to be discussed include the basic solubility relationships of iron, chromium, nickel, and refractory metals in these liquid metals, the results of inhibition studies, the role of oxygen on the corrosion processes, and specialized topics such as cavitation-corrosion and liquid metal embrittlement. Emphasis will be placed on utilizing the understanding gained in this earlier work on the development of heavy liquid metal targets in spallation neutron sources.

  5. Structure and thermal expansion of liquid bismuth

    Directory of Open Access Journals (Sweden)

    Mudry S.

    2015-12-01

    Full Text Available Experimental structural data for liquid Bi were used for estimation of the main structure parameters as well as the thermal expansion coefficient both in supercooled and superheated temperature ranges. It was shown that the equilibrium melt had a positive thermal expansion coefficient within a temperature range upon melting and a negative one at higher temperatures. The former was related to structure changes upon melting, whereas the latter with topologic disordering upon further heating. It was found that the superheated melt had a negative thermal expansion coefficient. The results obtained from structural data were compared with the thermal expansion coefficient calculated from the data of density for liquid Bi.

  6. Corrosion by liquid lead and lead-bismuth: experimental results review and analysis

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jinsuo [Los Alamos National Laboratory

    2008-01-01

    Liquid metal technologies for liquid lead and lead-bismuth alloy are under wide investigation and development for advanced nuclear energy systems and waste transmutation systems. Material corrosion is one of the main issues studied a lot recently in the development of the liquid metal technology. This study reviews corrosion by liquid lead and lead bismuth, including the corrosion mechanisms, corrosion inhibitor and the formation of the protective oxide layer. The available experimental data are analyzed by using a corrosion model in which the oxidation and scale removal are coupled. Based on the model, long-term behaviors of steels in liquid lead and lead-bismuth are predictable. This report provides information for the selection of structural materials for typical nuclear reactor coolant systems when selecting liquid lead or lead bismuth as heat transfer media.

  7. Ionic liquid polyoxometalates as light emitting materials

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz-acosta, Denisse [Los Alamos National Laboratory; Del Sesto, Rico E [Los Alamos National Laboratory; Scott, Brian [Los Alamos National Laboratory; Bennett, Bryan L [Los Alamos National Laboratory; Purdy, Geraldine M [Los Alamos National Laboratory; Muenchausen, Ross E [Los Alamos National Laboratory; Mc Kigney, Edward [Los Alamos National Laboratory; Gilbertson, Robert [Los Alamos National Laboratory

    2008-01-01

    The low melting point, negligible vapor pressure, good solubility, and thermal and chemical stability make ionic liquids useful materials for a wide variety of applications. Polyoxometalates are early transition metal oxygen clusters that can be synthesized in many different sizes and with a variety of heterometals. The most attractive feature of POMs is that their physical properties, in particular electrical, magnetic, and optical properties, can be easily modified following known procedures. It has been shown that POMs can exhibit cooperative properties, as superconductivity and energy transfer. POM ionic liquids can be obtained by selecting the appropliate cation. Different alkyl ammonium and alkyl phosphonium salts are being used to produce new POM ionic liquids together with organic or inorganic luminescent centers to design light emitting materials. Ammonium and phosphonium cations with activated, polymerizable groups are being used to further polymerize the ionic liquid into transparent, solid materials with high metal density.

  8. Electrochemical study on determination of diffusivity, activity and solubility of oxygen in liquid bismuth

    Energy Technology Data Exchange (ETDEWEB)

    Ganesan, Rajesh [Liquid Metals and Structural Chemistry Division, Chemistry Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Gnanasekaran, T. [Liquid Metals and Structural Chemistry Division, Chemistry Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India)]. E-mail: gnani@igcar.ernet.in; Srinivasa, Raman S. [Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology Bombay, Mumbai 400 076 (India)

    2006-06-15

    Diffusivity of oxygen in liquid bismuth was measured by potentiostatic method and is given bylg(D{sub O}{sup Bi}/cm{sup 2}.s{sup -1})(+/-0.042)=-3.706-1377/(TK{sup -1})(804bismuth was determined by coulometric titrations and using the measured data standard free energy of dissolution of oxygen in liquid bismuth was derived for the reaction:1/2O{sub 2}(g)=[O]{sub Bi}(at.%)and is given by{delta}G{sub O(Bi)}{sup o}/(J.g-atomO{sup -1})(+/-720)=-108784+20.356TK{sup -1}(753liquid bismuth was derived as a function of temperature and is given by the following expressions:lg(S/at%O)(+/-0.05)=-4476/TK{sup -1}+4.05(753liquid bismuth is compared with the literature data.

  9. Investigation of corrosion, water reaction, polonium evaporation and bismuth resource in liquid metal lead-bismuth technology

    Energy Technology Data Exchange (ETDEWEB)

    Takano, Hideki; Takizuka, Takakazu [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kitano, Teruaki [Mitsui Shipbuilding and Engineering Co. Ltd., Tokyo (Japan)

    2000-10-01

    Lead-bismuth is the first candidate material for liquid metal target find coolant of fueled blanket system in accelerator-driven system (ADS) studied at JAERI. Advantages of the lead-bismuth utilization are non-active material, very low capture cross section, low melting point of 125degC and high boiling point of 1670degC, and beside coolant void reactivity become negative. But problems are due to the high corrosivity to most of the structural materials and the corrosive data are scarcity. In this report, corrosivity, reaction with water, thermal-hydraulics, chemical toxicity etc. are studied by investigating some facilities utilized and researched really for lead or lead-bismuth. And, furthermore, polonium evaporation rate and bismuth resource are investigated. Main results obtained are as follows: (1) In a refinery, there are enough employment experience for liquid Pb-Bi in period of about 17 years and not corrosion for the thermal conductive materials (1Cr-0.5Mo steel) used under the condition of natural convection with temperature around 400degC. (2) In Russia, extensive experience in the use as Russian submarines and in R and D during about 50 years are available. And as a result, it will be able to lead approximately zero corrosion for Cr-Si materials by adjusting oxygen film with oxygen concentration control between 10{sup -7} to 10{sup -5}% mass. However, the corrosion data are not enough systematically collected involving them in radiation dose field. (3) In liquid-dropping experiment, it is shown that interaction between water and high temperature liquid Pb-Bi is reduced steeply with rising of atmosphere pressure. But, in order to design the second circuit removal model of ADS, the interaction should be evaluated by water continuous injection experiment. (4) Polonium forms PbPo in Pb-Bi, and the evaporation rate become less three factor than that of Po, and furthermore, the rate decreases in the atmosphere. The effects of Po on employee and environment

  10. Bismuth-ceramic nanocomposites through ball milling and liquid crystal synthetic methods

    Science.gov (United States)

    Dellinger, Timothy Michael

    Three methods were developed for the synthesis of bismuth-ceramic nanocomposites, which are of interest due to possible use as thermoelectric materials. In the first synthetic method, high energy ball milling of bismuth metal with either MgO or SiO2 was found to produce nanostructured bismuth dispersed on a ceramic material. The morphology of the resulting bismuth depended on its wetting behavior with respect to the ceramic: the metal wet the MgO, but did not wet on the SiO2. Differential Scanning Calorimetry measurements on these composites revealed unusual thermal stability, with nanostructure retained after multiple cycles of heating and cooling through the metal's melting point. The second synthesis methodology was based on the use of lyotropic liquid crystals. These mixtures of water and amphiphilic molecules self-assemble to form periodic structures with nanometer-scale hydrophilic and hydrophobic domains. A novel shear mixing methodology was developed for bringing together reactants which were added to the liquid crystals as dissolved salts. The liquid crystals served to mediate synthesis by acting as nanoreactors to confine chemical reactions within the nanoscale domains of the mesophase, and resulted in the production of nanoparticles. By synthesizing lead sulfide (PbS) and bismuth (Bi) particles as proof-of-concept, it was shown that nanoparticle size could be controlled by controlling the dimensionality of the nanoreactors through control of the liquid crystalline phase. Particle size was shown to decrease upon going from three-dimensionally percolating nanoreactors, to two dimensional sheet-like nanoreactors, to one dimensional rod-like nanoreactors. Additionally, particle size could be controlled by varying the precursor salt concentration. Since the nanoparticles did not agglomerate in the liquid crystal immediately after synthesis, bismuth-ceramic nanocomposites could be prepared by synthesizing Bi nanoparticles and mixing in SiO2 particles which

  11. Alkaline extraction of polonium from liquid lead bismuth eutectic

    Science.gov (United States)

    Heinitz, S.; Neuhausen, J.; Schumann, D.

    2011-07-01

    The production of highly radiotoxic polonium isotopes poses serious safety concerns for the development of future nuclear systems cooled by lead bismuth eutectic (LBE). In this paper it is shown that polonium can be extracted efficiently from LBE using a mixture of alkaline metal hydroxides (NaOH + KOH) in a temperature range between 180 and 350 °C. The extraction ratio was analyzed for different temperatures, gas blankets and phase ratios. A strong dependence of the extraction performance on the redox properties of the cover gas was found. While hydrogen facilitates the removal of polonium, oxygen has a negative influence on the extraction. These findings open new possibilities to back up the safety of future LBE based nuclear facilities.

  12. In situ transmission electron microscopy of solid-liquid phase transition of silica encapsulated bismuth nanoparticles

    Science.gov (United States)

    Hu, Jianjun; Hong, Yan; Muratore, Chris; Su, Ming; Voevodin, Andrey A.

    2011-09-01

    The solid-liquid phase transition of silica encapsulated bismuth nanoparticles was studied by in situ transmission electron microscopy (TEM). The nanoparticles were prepared by a two-step chemical synthesis process involving thermal decomposition of organometallic precursors for nucleating bismuth and a sol-gel process for growing silica. The microstructural and chemical analyses of the nanoparticles were performed using high-resolution TEM, Z-contrast imaging, focused ion beam milling, and X-ray energy dispersive spectroscopy. Solid-liquid-solid phase transitions of the nanoparticles were directly recorded by electron diffractions and TEM images. The silica encapsulation of the nanoparticles prevented agglomeration and allowed particles to preserve their original volume upon melting, which is desirable for applications of phase change nanoparticles with consistently repeatable thermal properties.

  13. Luminescence properties of IR-emitting bismuth centres in SiO{sub 2}-based glasses in the UV to near-IR spectral region

    Energy Technology Data Exchange (ETDEWEB)

    Firstova, E G; Vel' miskin, V V; Firstov, S V; Dianov, E M [Fiber Optics Research Center, Russian Academy of Sciences, Moscow (Russian Federation); Bufetov, I A [Moscow Institute of Physics and Technology (State University), Dolgoprudnyi, Moscow Region (Russian Federation); Khopin, V F; Gur' yanov, A N [G.G.Devyatykh Institute of Chemistry of High-Purity Substances, Russian Academy of Sciences, Nizhnii Novgorod (Russian Federation); Bufetova, G A [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation); Nishchev, K N [N.P. Ogarev Mordovia State University, Physics and Chemistry Institute, Saransk (Russian Federation)

    2015-01-31

    We have studied UV excitation spectra of IR luminescence in bismuth-doped glasses of various compositions and obtained energy level diagrams of IR-emitting bismuth-related active centres (BACs) associated with silicon and germanium atoms up to ∼5.2 eV over the ground level. A possible energy level diagram of the BACs in phosphosilicate glass has been proposed. The UV excitation peaks for the IR luminescence of the BACs in the glasses have been shown to considerably overlap with absorption bands of the Bi{sup 3+} ion, suggesting that Bi{sup 3+} may participate in BAC formation. (optical fibres)

  14. Luminescence properties of IR-emitting bismuth centres in SiO2-based glasses in the UV to near-IR spectral region

    Science.gov (United States)

    Firstova, E. G.; Bufetov, I. A.; Khopin, V. F.; Vel'miskin, V. V.; Firstov, S. V.; Bufetova, G. A.; Nishchev, K. N.; Gur'yanov, A. N.; Dianov, E. M.

    2015-01-01

    We have studied UV excitation spectra of IR luminescence in bismuth-doped glasses of various compositions and obtained energy level diagrams of IR-emitting bismuth-related active centres (BACs) associated with silicon and germanium atoms up to ~5.2 eV over the ground level. A possible energy level diagram of the BACs in phosphosilicate glass has been proposed. The UV excitation peaks for the IR luminescence of the BACs in the glasses have been shown to considerably overlap with absorption bands of the Bi3+ ion, suggesting that Bi3+ may participate in BAC formation.

  15. Tb{sup 3+} doped Zinc Alumino Bismuth Borate glasses for green emitting luminescent devices

    Energy Technology Data Exchange (ETDEWEB)

    Swapna, K.; Mahamuda, Sk. [Department of Physics, K L University, Green Fields, Vaddeswaram, Guntur (Dt), Andhra Pradesh 522502 (India); Rao, A. Srinivasa, E-mail: drsrallam@gmail.com [Department of Physics, K L University, Green Fields, Vaddeswaram, Guntur (Dt), Andhra Pradesh 522502 (India); Department of Applied Physics, Delhi Technological University, Bawana Road, New Delhi 110042 (India); Jayasimhadri, M. [Department of Applied Physics, Delhi Technological University, Bawana Road, New Delhi 110042 (India); Shakya, Suman; Prakash, G. Vijaya [Nanophotonics Laboratory, Department of Physics, Indian Institute of Technology-Delhi, Hauz Khas, New Delhi 110016 (India)

    2014-12-15

    Zinc Alumino Bismuth Borate (ZnAlBiB) glasses doped with terbium (Tb{sup 3+}) ions with a chemical composition 20ZnO–10Al{sub 2}O{sub 3}–(10−x)Bi{sub 2}O{sub 3}–60B{sub 2}O{sub 3}−xTb{sub 2}O{sub 3} (x=0.1, 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 mol%) were prepared by a conventional melt quenching method and studied their optical absorption, photoluminescence and decay spectral properties. The Judd–Ofelt (J–O) parameters evaluated from the experimental oscillator strengths were used to measure the radiative properties for the prominent luminescent transitions of Tb{sup 3+} ions such as {sup 5}D{sub 4}→{sup 7}F{sub 6}, {sup 7}F{sub 5}, {sup 7}F{sub 4} and {sup 7}F{sub 3.} The effect of Tb{sup 3+} ion concentration on the luminescence process observed in the visible region was discussed in detail. The emission spectra recorded for all the ZnAlBiB glasses doped with Tb{sup 3+} ions, show an intense peak in green region at 542 nm. The stimulated emission cross-section, branching ratios and quantum efficiency values evaluated for green emission ({sup 5}D{sub 4}→{sup 7}F{sub 5}) suggests the utility of these glasses for green luminescence applications. It was found that, within the concentration range investigated, 2.5 mol% of Tb{sup 3+} doped ZnAlBiB glass is most suitable for green luminescence applications at 542 nm in principle. - Highlights: • ZnAlBiB glasses doped with Tb{sup 3+} ions were prepared by a conventional melt quenching technique. • Judd–Ofelt and radiative properties are measured from the emission spectra. • Quantum efficiency of the ZnAlBiB glasses is measured by using radiative and measured lifetimes. • CIE Chromaticity co-ordinates are evaluated from emission spectra.

  16. Liquid phase epitaxial growth of bismuth based superconductors

    Science.gov (United States)

    Takemoto, J.; Miyashita, S.; Inoue, T.; Komatsu, H.

    1996-05-01

    The liquid phase epitaxial growth of superconducting films of Bi 2Sr 2CaCu 2O y (2212 phase) and Bi 2Sr 2CuO z (2201 phase) were carried out on three types of substrates; SrTiO 3, LaAlO 3 and NdGaO 3. Twinning structures of the 2212 phase were observed in the films grown on the SrTiO 3 (100) and LaAlO 3 (100) substrates which belong to the cubic crystal system, while nearly twin-free structures were obtained when the film was grown on the NdGaO 3 (001) substrate (orthorhombic system). Atomic force microscopy revealed a 2201 phase film with a reasonably flat area (several μm 2) grown on the LaAlO 3 (100) substrate. It was observed that the 2212 phase nucleated on the substrate following the Volmer-Weber type mechanism (three-dimensional island growth mode). The enlarging processes of the island layers were discussed.

  17. Dispersive Liquid-Liquid Microextraction of Bismuth in Various Samples and Determination by Flame Atomic Absorption Spectrometry

    Directory of Open Access Journals (Sweden)

    Teslima Daşbaşı

    2016-01-01

    Full Text Available A dispersive liquid-liquid microextraction method for the determination of bismuth in various samples by flame atomic absorption spectrometry is described. In this method, crystal violet was used as counter positive ion for BiCl4- complex ion, chloroform as extraction solvent, and ethanol as disperser solvent. The analytical parameters that may affect the extraction efficiency like acidity of sample, type and amount of extraction and disperser solvents, amount of ligand, and extraction time were studied in detail. The effect of interfering ions on the analyte recovery was also investigated. The calibration graph was linear in the range of 0.040–1.00 mg L−1 with detection limit of 4.0 μg L−1 (n=13. The precision as relative standard deviation was 3% (n=11, 0.20 mg L−1 and the enrichment factor was 74. The developed method was applied successfully for the determination of bismuth in various water, pharmaceutical, and cosmetic samples and the certified reference material (TMDA-64 lake water.

  18. Physical chemistry of corrosion and oxygen control in liquid lead and lead-bismuth eutectic

    Energy Technology Data Exchange (ETDEWEB)

    Schroer, C.; Konys, J.

    2007-12-15

    Corrosion of steel in liquid lead (Pb) and lead-bismuth eutectic (LBE) is an important factor when applying these materials as a process medium. At low oxygen content of the liquid-metal phase, the degradation results mainly from the dissolution of the steel constituents, which may significantly decrease in the presence of a continuous scale of oxides of the steel constituents on the steel surface. In order to facilitate the formation of such a scale, the oxygen content of the liquid metal has to be controlled. Therefore, a method of measuring the oxygen content must be available. This report addresses the thermodynamic fundamentals of steel corrosion in oxygen-containing liquid metals and provides the data on chemical and physical properties which is required for the determination of favourable conditions with respect to the oxygen content and the numerical analysis of the dissolution of the primary steel constituents in oxygen-containing liquid Pb and LBE. Furthermore, the measurement of the oxygen content with electrochemical oxygen sensors and the evaluation of the sensor output is discussed. (orig.)

  19. Short-Range Wetting at Liquid Gallium-Bismuth Alloy Surfaces: X-Ray Measurements and Square-Gradient Theory

    OpenAIRE

    Huber, Patrick; Shpyrko, Oleg; Pershan, Peter S.; Ocko, Ben; DiMasi, Elaine; Deutsch, Moshe

    2003-01-01

    We present an x-ray reflectivity study of wetting at the free surface of the binary liquid metal alloy gallium-bismuth (Ga-Bi) in the region where the bulk phase separates into Bi-rich and Ga-rich liquid phases. The measurements reveal the evolution of the microscopic structure of the wetting films of the Bi-rich, low-surface-tension phase along several paths in the bulk phase diagram. The wetting of the Ga-rich bulk’s surface by a Bi-rich wetting film, the thickness of which is limited by gr...

  20. A study of early corrosion behaviors of FeCrAl alloys in liquid lead-bismuth eutectic environments

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Jun [Nuclear Transmutation Energy Research Center of Korea (NUTRECK), Seoul National University, San 56-1 Shinlim-dong, Gwanak-ku, Seoul 151-742 (Korea, Republic of); Interdisciplinary School of Green Energy, Ulsan National Institute of Science and Technology, 100 Banyeon-ri, Eonyang-eup, Ulju-gun, Ulsan 689-798 (Korea, Republic of); Nam, Hyo On; Hwang, Il Soon [Nuclear Transmutation Energy Research Center of Korea (NUTRECK), Seoul National University, San 56-1 Shinlim-dong, Gwanak-ku, Seoul 151-742 (Korea, Republic of); Kim, Ji Hyun, E-mail: kimjh@unist.ac.k [Interdisciplinary School of Green Energy, Ulsan National Institute of Science and Technology, 100 Banyeon-ri, Eonyang-eup, Ulju-gun, Ulsan 689-798 (Korea, Republic of)

    2010-12-31

    Lead and lead-bismuth eutectic (LBE) alloy have been increasingly receiving attention as heavy liquid metal coolants (HLMC) for future nuclear energy systems. The compatibility of structural materials and components with lead-bismuth eutectic liquid at high temperature is one of key issues for the commercialization of lead fast reactors. In the present study, the corrosion behaviors of iron-based alumina-forming alloys (Kanthal-AF (registered) , PM2000, MA956) were investigated by exposing to stagnant LBE environments at 500 {sup o}C and 550 {sup o}C for up to 500 h. After exposures, the thickness and chemistry of the oxide layer on the specimens were analyzed by scanning electron microscopy, scanning transmission electron microscopy and energy dispersive X-ray spectroscopy. As a result, the oxide characteristics and the corrosion resistance were compared. In this study, it was shown that the corrosion resistance of FeCrAl ODS steels (PM2000, MA956) are superior to that of FeCrAl ferritic steel (Kanthal-AF (registered)) in higher temperature LBE.

  1. Selective scattering polymer dispersed liquid crystal film for light enhancement of organic light emitting diode.

    Science.gov (United States)

    Jiang, Jinghua; McGraw, Greg; Ma, Ruiqing; Brown, Julie; Yang, Deng-Ke

    2017-02-20

    We developed a novel light enhancing film for an organic light emitting diode (OLED) based on polymer dispersed liquid crystal (PDLC). In the film, the liquid crystal droplets are unidirectionally aligned along the film normal direction and exhibit selective scattering. The film scatters light emitted only in directions with large incident angles but not light emitted in directions with small incident angles. When the light is scattered, it changes propagation direction and exits the OLED. The PDLC film reduces the total internal reflection and thus can significantly increase the light efficiency of the OLED.

  2. Diffusion-controlled intergranular penetration and embrittlement of copper by liquid bismuth between 300 and 600 Celsius degrees; Penetration intergranulaire fragilisante du cuivre par le bismuth liquide: identification de la cinetique et du mecanisme de type diffusionnel entre 300 et 600 deg

    Energy Technology Data Exchange (ETDEWEB)

    Laporte, V

    2005-02-15

    Hybrid reactors are a new concept for energy production and nuclear waste treatment. Among other requirements, structural materials have to withstand liquid metal embrittlement. This thesis aimed therefore to identify the controlling mechanism for the intergranular embrittlement of copper in contact with liquid bismuth. Scanning electron microscopy, Auger electron spectroscopy, X-ray photoelectron spectroscopy and Rutherford backscattering spectroscopy have been used to analyze fracture surfaces of both copper polycrystals and a copper bicrystal (symmetric tilt boundary 50 degrees <100>). These analyses reveal both parabolic intergranular penetration kinetics and a maximal intergranular bismuth concentration that is less than two monolayers equivalent. These two results allow us to identify grain boundary diffusion as the controlling mechanism for the intergranular penetration of copper by liquid bismuth between 300 and 600 Celsius degrees, showing the absence of perfect grain boundary wetting. (author)

  3. Preparation of bismuth subcarbonate by liquid ball-milling transformation method from bismuth oxide%液相球磨法由氧化铋制备次碳酸铋的动力学

    Institute of Scientific and Technical Information of China (English)

    叶龙刚; 蒋叶; 唐朝波; 陈永明; 唐谟堂

    2014-01-01

    In order to solve the problems of environment pollution and high cost in traditional process of bismuth subcarbonate preparation, a new process using ball-milling transformation method from NH4HCO3 and Bi2O3 was proposed. Additionally, the kinetics of bismuth subcarbonate preparation was studied. Effects of reaction temperature, particle size of bismuth oxide, solid-to-liquid ratio and concentrations of ammonium bicarbonate on the conversion rate of bismuth oxide were studied. The results indicate that the conversion rate of bismuth oxide significantly increased under the conditions of higher temperature, smaller particle size, higher concentration of ammonium bicarbonate and smaller solid-to-liquid ratio. The XRD and ICP-AES analyses show that the purity of product is high. The reaction kinetics with activation energy of 9.783 kJ/mol was analyzed by shrinking core model, and the whole transformation process is controlled by solid product layer diffusion. A semi-empirical kinetics equation was obtained to describe the conversion process.%为解决传统次碳酸铋生产过程中成本高和环境污染问题,提出采用液相球磨法由氧化铋制备次碳酸铋的新工艺,研究用碳酸氢氨和氧化铋制备次碳酸铋反应过程的动力学,考察反应温度、氧化铋粒度、液固比以及碳酸氢氨浓度对氧化铋转化率的影响。结果表明,在9~30°C的范围内,升高反应温度、减小氧化铋粉末的粒度、扩大液固比以及提高碳酸氢氨浓度均有利于氧化铋转化率的提高。对反应产物的表征分析表明,产品的纯度较高、杂质少;SEM结果显示产品次碳酸铋主要呈针棒状形态。反应过程受产物层的扩散控制,可用未反应收缩核模型描述,反应的表观活化能为9.783 kJ/mol,同时获得了描述反应过程的半经验动力学方程。

  4. Correlation of the "EMIT" antiepileptic drug assay with a gas liquid chromatographic method.

    Science.gov (United States)

    Legaz, M; Raisys, V A

    1976-02-01

    Many methodologies have been developed for determining anticonvulsant drug levels in human serum. Unfortunately, most procedures are either time consuming or subject to a variety of interferring substances. The "Enzyme Multiplied Immunoassay Technique" (EMIT) system has been evaluated for its speed, sensitivity, accuracy, and precision. When compared with a gas-liquid chromatographic procedure, the EMIT assay appeared to yield results which were statistically comparable for the drugs diphenylhydantoin, phenobarbital, and primidone. The EMIT assay also demonstrated no significant interference when challenged with extraordinarily high levels of potentially cross reacting drugs. Results obtained with the EMIT assay correlated well with GLC data and rank it as an attractive alternative to many of the existing procedures now being used.

  5. Liquid metal embrittlement susceptibility of T91 steel by Lead-Bismuth

    OpenAIRE

    Auger, Thierry; Lorang, Gérard

    2004-01-01

    submitted to Scripta Materialia; Previous studies on T91 steel in its standard metallurgical state found no evidence for Liquid Metal Embrittlement (LME) by eutectic Pb-Bi. In this paper, we report clear evidence that this steel can be embrittled by Pb-Bi when direct contact between the steel and the liquid metal is obtained by prior ion beam sputtering.

  6. Structure of liquid caesium-bismuth alloys studied by neutron diffraction

    NARCIS (Netherlands)

    van der Aart, SA; Verhoeven, VWJ; Verkerk, P; van der Lugt, W

    2000-01-01

    Neutron diffraction experiments were carried out for two liquid alloys with compositions CsBi and Cs3Bi2. The results indicate that probably polyanions with an average number of about two Bi atoms per cluster are formed. This result contrasts with that for liquid Cs-Sb, which contains larger chains

  7. THORIUM DISPERSION IN BISMUTH

    Science.gov (United States)

    Bryner, J.S.

    1961-07-01

    The growth of thorium bismutaide particles, which are formed when thorium is suspended in liquid bismuth, is inhibited when the liquid metal suspension is being flowed through a reactor and through a heat exchanger in sequence. It involves the addition of as little as 1 part by weight of tellurium to 100 parts of thorium. This addition is sufficient to inhibit particle growth and agglomeration.

  8. Birefringence-dependent linearly-polarized emission in a liquid crystalline organic light emitting polymer.

    Science.gov (United States)

    Lee, Dong-Myoung; Lee, You-Jin; Kim, Jae-Hoon; Yu, Chang-Jae

    2017-02-20

    We investigated the linearly polarized emission of uniformly aligned poly(9,9-di-n-octylfluorenyl-2,7-diyl)-alt-(benzo[2,1,3]thia-diazol-4,8-diyl) (F8BT) with a liquid crystalline phase on a rubbed alignment layer. The polarization ratio, defined by the ratio of luminous intensities polarized parallel and perpendicular to the rubbed direction, gradually decreased with increasing thickness of the F8BT film. In the photoluminescence (PL) process, the polarized light is emitted throughout the whole F8BT film, while in the electroluminescence (EL) process, the polarized light is emitted at a certain region within the F8BT film. The thickness-dependent polarization ratios in both PL and EL processes were successfully described based on a simple model wherein the mean optical birefringence was expressed as a function of the thickness of the F8BT film.

  9. Controlled electrodeposition of bismuth nanocatalysts for the solution-liquid-solid synthesis of CdSe nanowires on transparent conductive substrates.

    Science.gov (United States)

    Reim, Natalia; Littig, Alexander; Behn, Dino; Mews, Alf

    2013-12-11

    Semiconductor nanowires (NWs) composed of cadmium selenide (CdSe) have been directly grown on transparent conductive substrates via the solution-liquid-solid (SLS) approach using electrodeposited bismuth nanoparticles (Bi NPs) as catalyst. Bi NPs were fabricated on indium tin oxide (ITO) surfaces from a bismuth trichloride solution using potentiostatic double-pulse techniques. The size and density of electrodeposited Bi NPs were controlled by the pulse parameters. Since the NW diameter is governed by the dimension of the Bi catalyst, the electrodeposition is a reliable method to synthesize nanowires directly on substrates with a desired size and density. We show that the density can be adjusted from individual NWs on several square micrometer to very dense NW networks. The diameter can be controlled between thick nanowires above 100 nm to very thin NW of 7 nm in diameter, which is well below the respective exciton dimension. Hence, especially the thinnest NWs exhibit diameter-dependent photoluminescence energies as a result of quantum confinement effects in the radial dimension.

  10. Use of the transpiration method to study polonium evaporation from liquid lead-bismuth eutectic at high temperature

    Energy Technology Data Exchange (ETDEWEB)

    Prieto, Borja Gonzalez [SCKCEN (Belgian Nuclear Research Centre), Mol (Belgium); KU Leuven, Heverlee (Belgium). Centre of Surface Chemistry and Catalysis; Marino, Alessandro [SCKCEN (Belgian Nuclear Research Centre), Mol (Belgium); Vrije Universiteit Brussel, Elsene (Belgium); Lim, Jun; Rosseel, Kris; Bosch, Joris van den; Aerts, Alexander [SCKCEN (Belgian Nuclear Research Centre), Mol (Belgium); Martens, Johan [KU Leuven, Heverlee (Belgium). Centre of Surface Chemistry and Catalysis; Rizzi, Matthias; Neuhausen, Joerg [Paul Scherrer Institute, Villigen (Switzerland). Lab. for Radio- and Environmental Chemistry

    2014-07-01

    Qualitative and quantitative understanding of Po volatilization under different conditions is of key importance for safety assessments of lead-bismuth eutectic (LBE) based nuclear reactors, spallation targets and accelerator driven systems. In this work we explore the possibilities of the transpiration method in combination with simple models to study the equilibrium and kinetics of Po evaporation from highly diluted solutions in lead-bismuth eutectic between 600 and 1000 C in Ar/5% H{sub 2} and Ar. On the basis of evaporation experiments at various carrier gas flow rates, we identified the conditions of vapor saturation allowing the determination of equilibrium constants. From the limiting behavior at high flow rates, values for the maximal evaporation rate of Po from LBE were estimated. Measurements of evaporation as a function of time were consistent with the assumption that polonium dissolved in LBE obeys Henry's law. A theoretical analysis furthermore suggested that diffusion of polonium in LBE was not a rate limiting factor for evaporation under vapor saturation conditions. Newly determined values for the Henry constant of Po in LBE between 600 and 1000 C were consistent with previously derived correlations.

  11. Efficient vacuum-free-processed quantum dot light-emitting diodes with printable liquid metal cathodes.

    Science.gov (United States)

    Peng, Huiren; Jiang, Yibin; Chen, Shuming

    2016-10-20

    Colloidal quantum dot light-emitting diodes (QLEDs) are recognized as promising candidates for next generation displays. QLEDs can be fabricated by low-cost solution processing except for the metal electrodes, which, in general, are deposited by costly vacuum evaporation. To be fully compatible with the low-cost solution process, we herein demonstrate vacuum-free and solvent-free fabrication of electrodes using a printable liquid metal. With eutectic gallium-indium (EGaIn) based liquid metal cathodes, vacuum-free-processed QLEDs are demonstrated with superior external quantum efficiencies of 11.51%, 12.85% and 5.03% for red, green and blue devices, respectively, which are about 2-, 1.5- and 1.1-fold higher than those of the devices with thermally evaporated Al cathodes. The improved performance is attributable to the reduction of electron injection by the native oxide of EGaIn, which serves as an electron-blocking layer for the devices and thus improves the balance of carrier injection. Also, the T50 half-lifetime of the vacuum-free-processed QLEDs is about 2-fold longer than that of the devices with Al cathodes. Our results demonstrate that EGaIn-based solvent-free liquid metals are promising printable electrodes for realizing efficient, low-cost and vacuum-free-processed QLEDs. The elimination of vacuum and high-temperature processes significantly reduces the production cost and paves the way for industrial roll-to-roll manufacturing of large area displays.

  12. Fundamental emission characteristics of light-emitting liquid crystal cells with rubrene-doped 4-cyano-4'-pentylbiphenyl

    Science.gov (United States)

    Honma, Michinori; Horiuchi, Takao; Tanimoto, Masashi; Nose, Toshiaki

    2014-06-01

    We have investigated the light emission properties in rubrene-doped nematic liquid crystal (LC) cells from the following three standpoints: (i) effect of the heating temperature during the sample preparation, (ii) role of the emissive LC layer thickness, and (iii) role of different LC types used as the emissive layer. As a result, the light-emitting LC cells simultaneously exhibit the features of electrochemiluminescent cells (the carrier transport is governed by an ionic conduction) as well as of organic light-emitting diodes (the luminance strongly depends on the emissive layer thickness). Furthermore, we report that devices with cyano group containing LCs exhibit higher luminance compared to a fluorinated LC.

  13. Novel Bismuth Nanotubes

    Institute of Scientific and Technical Information of China (English)

    苏长荣; 李家明

    2002-01-01

    Theoretical investigations show that bismuth nanotubes are semiconductors for all diameters. For smalldiameter bismuth nanotubes, the band structures and bandgaps vary strongly with the strong hybridization effect. When the diameters are larger than 18 A, the bandgaps ofBi (n, n) and (n, 0) nanotubes approach 0.63 e V, corresponding to the bandgap of bismuth sheet at the Γ point. Thus, bismuth nanotubes are expected to be a potential semiconductor nanomaterial in future nanoelectronics.

  14. Structure of unsupported bismuth nanoparticles

    Science.gov (United States)

    Wurl, A.; Hyslop, M.; Brown, S. A.; Hall, B. D.; Monot, R.

    We present new results of electron diffraction experiments on unsupported nanometer-sized bismuth clusters. The high intensity cluster beam, necessary for electron diffraction, is provided by an inert-gas aggregation source. The cluster beam contains particles with average cluster sizes between 4.5 and 10 nm. When using Helium as a carrier gas we are able to observe a transition from crystalline clusters to a new structure, which we identify with that of amorphous or liquid clusters.

  15. Measurements of gas and volatile element production rates from an irradiated molten lead and lead-bismuth spallation target with proton beams of 1 and 1.4 GeV; Mesures de taux de production d'elements gazeux et volatiles lors de reactions induites par des protons de 1 et 1,4 GeV sur des cibles epaisses de plomb et plomb-bismuth liquides

    Energy Technology Data Exchange (ETDEWEB)

    Tall, Y

    2008-03-15

    The integrated project EUROTRANS (European Research Programme for the Transmutation of High Level Nuclear Waste in an Accelerator Driven System) of the 6. EURATOM Framework Programme aims to demonstrate the transmutation of radioactive waste in ADS (Accelerator Driven Sub-critical system). It will carry out a first advanced design of an experimental facility to demonstrate the technical feasibility of transmutation, and will produce a conceptual design of an industrial facility dedicated to transmutation. An ADS consists of three fundamental elements: the accelerator of protons, the sub-critical core and the spallation target. SUBATECH (physique Sub-Atomique et des Technologies associees) laboratory is involved to the study of the chosen liquid lead-bismuth as a spallation ADS target. The irradiation of liquid lead-bismuth target with energetic proton beam generates in addition to neutrons, volatile and radioactive residues. In order to determine experimentally the production rates of gas and volatile elements following a spallation reaction in a lead-bismuth target, the experiment IS419 was performed at the ISOLDE facility at CERN (Centre Europeen de la Recherche Nucleaire). This experiment constitutes the frame of the thesis whose main objective is to assess and study the production and release rates of many gas and volatile element from the irradiated lead-bismuth target with an energetic proton beam. The obtained data are compared to Monte Carlo simulation code (MCNPX) results in order to test the intranuclear cascade model of Bertini and of Cugnon, and the evaporation options of Dresner and Schmidt. (author)

  16. Nanocalorimetry of bismuth nanoparticles

    Science.gov (United States)

    Olson, Eric Ashley

    The properties of nanosized bismuth particles are investigated using a nanocalorimetric technique. A brief description of the experimental method and data analysis procedures is reported. Bismuth nanoparticles are found to melt at a temperature below that of bulk material, but higher than expected using the standard model. Also included is the results of a finite element analysis and simulated melting of bismuth films on various kinds of sensors. Temperature distributions are found to be nonuniform for calorimetric sensors with Al metallizations, but much more uniform for Pt metallized sensors. The consequences of this nonuniformity on caloric data are discussed.

  17. Study of liquid transparent encapsulants for the packaging of light emitting diode and other optoelectronic devices

    Science.gov (United States)

    Zhou, Yan

    Optically transparent polymeric materials required for the encapsulation of optoelectronic chips are critical to the manufacturability, cost, performance, and reliability of LED and other optoelectronic devices. This work is focused on the development of the transparent epoxy based liquid encapsulants with the objective to enhance the manufacturability, to reduce the cost, and to improve both the performance and the reliability of the packaged optoelectronic devices. First, three transparent encapsulants based on different chemistries were reviewed and their properties compared. These encapsulant systems serve as models of different epoxy chemistries suitable for LED applications. The experimental result gives an overview of the characteristics of each system and guides the further development of the encapsulant for different packaging needs. Then, two new encapsulants were developed and introduced. The first one was a two-component encapsulant based on DGEBA/MHHPA chemistry, but provides lower internal stress, better transmission retention upon thermal aging, and easier processing compared with the current best performer based on the same chemistry. The second one is a novel one-component, low temperature and fast cure encapsulant with a high refractive index of 1.6. This encapsulant provides not only the easy handling, convenient storage, and energy saving, but also higher light output for the packaged LED devices. The third part of this work deals with nanocomposites based on aromatic epoxy and cycloaliphatic epoxy. It was found that these composites provide lower CTE, better toughness, and other advantages while keeping good transparency, therefore are suitable for LED applications. Toughening is another topic studied. Three toughened transparent encapsulants were introduced and compared. The toughening agents selected effectively increased the toughness of the cycloaliphatic epoxy/MHHPA system with minimum negative effect on the transmission of the

  18. Bismuth vanadate process

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, R.M.

    1990-06-26

    This patent describes the process for the preparation of bismuth vanadate and bismuth vanadate-containing compounds wherein the precursor materials are calcined in the solid state at temperatures sufficient to react the precursor materials to prepare the vanadate compounds. It comprises: wet grinding the calcined product, contacting the calcined product with sufficient alkaline material to provide a pH level of 7.0-13.0 and recovering the treated product, the wet grinding of the calcined product being conducted either in the presence of the alkaline material or prior to the contacting with the alkaline material.

  19. Microfluidic White Organic Light-Emitting Diode Based on Integrated Patterns of Greenish-Blue and Yellow Solvent-Free Liquid Emitters

    Science.gov (United States)

    Kobayashi, Naofumi; Kasahara, Takashi; Edura, Tomohiko; Oshima, Juro; Ishimatsu, Ryoichi; Tsuwaki, Miho; Imato, Toshihiko; Shoji, Shuichi; Mizuno, Jun

    2015-01-01

    We demonstrated a novel microfluidic white organic light-emitting diode (microfluidic WOLED) based on integrated sub-100-μm-wide microchannels. Single-μm-thick SU-8-based microchannels, which were sandwiched between indium tin oxide (ITO) anode and cathode pairs, were fabricated by photolithography and heterogeneous bonding technologies. 1-Pyrenebutyric acid 2-ethylhexyl ester (PLQ) was used as a solvent-free greenish-blue liquid emitter, while 2,8-di-tert-butyl-5,11-bis(4-tert-butylphenyl)-6,12-diphenyltetracene (TBRb)-doped PLQ was applied as a yellow liquid emitter. In order to form the liquid white light-emitting layer, the greenish-blue and yellow liquid emitters were alternately injected into the integrated microchannels. The fabricated electro-microfluidic device successfully exhibited white electroluminescence (EL) emission via simultaneous greenish-blue and yellow emissions under an applied voltage of 100 V. A white emission with Commission Internationale de l’Declairage (CIE) color coordinates of (0.40, 0.42) was also obtained; the emission corresponds to warm-white light. The proposed device has potential applications in subpixels of liquid-based microdisplays and for lighting. PMID:26439164

  20. Magnetic iron oxide nanoparticles for the collection and direct measurement of adsorbed alpha-emitting radionuclides from environmental waters by liquid scintillation analysis

    Energy Technology Data Exchange (ETDEWEB)

    O' Hara, Matthew J.; Addleman, R. Shane

    2017-01-01

    Radioactive contamination in the environment, be it from accidental or intentional release, can create an urgent need to assess water and food supplies, the environment, and monitor human health. Alpha-emitting radionuclides represent the most ionizing, and therefore the most damaging, form of radiation when internalized. Additionally, because of its ease of energy attenuation in solids or liquids, alpha emissions cannot be reliably monitored using non-destructive means. In the event of such an emergency, rapid and efficient methods will be needed to screen scores of samples (food, water, and human excreta) within a short time window. Unfortunately, the assay of alpha-emitting radionuclides using traditional radioanalytical methods is typically labor intensive and time consuming. The creation of analytical counting sources typically requires a series of chemical treatment steps to achieve well performing counting sources. In an effort to devise radioanalytical methods that are fast, require little labor, and minimize the use of toxic or corrosive agents, researchers at PNNL have evaluated magnetite (Fe3O4) nanoparticles as extracting agents for alpha-emitting radionuclides from chemically unmodified aqueous systems. It is demonstrated that bare magnetic nanoparticles exhibit high affinity for representative α-emitting radionuclides (241Am and 210Po) from representative aqueous matrices: river and ground water. Furthermore, use of the magnetic properties of these materials to concentrate the sorbed analyte from the bulk aqueous solution has been demonstrated. The nanoparticle concentrate can be either directly dispensed into scintillation cocktail, or first dissolved and then added to scintillation cocktail as a solution for alpha emission assay by liquid scintillation analysis. Despite the extreme quench caused by the metal oxide suspensions, the authors have demonstrated that quench correction features available on modern liquid scintillation analyzers can be

  1. Bismuth incorporation into gallium phosphide

    Energy Technology Data Exchange (ETDEWEB)

    Jena, Puru [Virginia Commonwealth Univ. (United States); Kandalam, Anil K. [West Chester Univ. of Pennsylvania (United States); Christian, Theresa M. [National Renewable Energy Lab. (United States); Beaton, Daniel A. [National Renewable Energy Lab. (United States); Mascarenhas, Angelo [National Renewable Energy Lab. (United States); Alberi, Kirstin [National Renewable Energy Lab. (United States)

    2016-12-21

    Gallium phosphide bismide (GaP1-xBix) epilayers with bismuth fractions from 0.9% to 3.2%, as calculated from lattice parameter measurements, were studied with Rutherford backscattering spectrometry (RBS) to directly measure bismuth incorporation. The total bismuth fractions found by RBS were higher than expected from the lattice parameter calculations. Furthermore, in one analyzed sample grown by molecular beam epitaxy at 300 degrees C, 55% of incorporated bismuth was found to occupy interstitial sites. We discuss implications of this high interstitial incorporation fraction and its possible relationship to x-ray diffraction and photoluminescence measurements of GaP0.99Bi0.01.

  2. Dissolution corrosion of 316L austenitic stainless steels in contact with static liquid lead-bismuth eutectic (LBE) at 500 °C

    Science.gov (United States)

    Lambrinou, Konstantina; Charalampopoulou, Evangelia; Van der Donck, Tom; Delville, Rémi; Schryvers, Dominique

    2017-07-01

    This work addresses the dissolution corrosion behaviour of 316L austenitic stainless steels. For this purpose, solution-annealed and cold-deformed 316L steels were simultaneously exposed to oxygen-poor (lead-bismuth eutectic (LBE) for 253-3282 h at 500 °C. Corrosion was consistently more severe for the cold-drawn steels than the solution-annealed steel, indicating the importance of the steel thermomechanical state. The thickness of the dissolution-affected zone was non-uniform, and sites of locally-enhanced dissolution were occasionally observed. The progress of LBE dissolution attack was promoted by the interplay of certain steel microstructural features (grain boundaries, deformation twin laths, precipitates) with the dissolution corrosion process. The identified dissolution mechanisms were selective leaching leading to steel ferritization, and non-selective leaching; the latter was mainly observed in the solution-annealed steel. The maximum corrosion rate decreased with exposure time and was found to be inversely proportional to the depth of dissolution attack.

  3. Layered bismuth vanadate ferroelectrics

    Energy Technology Data Exchange (ETDEWEB)

    Osipyan, V.G.; Savchenko, L.M.; Elbakyan, V.L.; Avakyan, P.B.

    1987-08-01

    The authors synthesize new layered bismuth vanadate ferroelectrics. The x-ray diffraction characteristics of Bi/sub 2/VO/sub 5.5/ are shown. Thermal expansion of ceramics with various compositions are presented, as are the temperature dependences of the dielectric constant of the ceramic with various compositions. Unit-cell parameters, Curie temperature, electrical conductivity and the dielectric characteristics of the compositions studied are shown.

  4. Tribochemistry of Bismuth and Bismuth Salts for Solid Lubrication

    NARCIS (Netherlands)

    Gonzalez Rodriguez, P.; Nieuwenhuijzen, van den K.J.H.; Lette, W.; Schipper, D.J.; Elshof, ten J.E.

    2016-01-01

    One of the main trends in the past decades is the reduction of wastage and the replacement of toxic compounds in industrial processes. Some soft metallic particles can be used as nontoxic solid lubricants in high-temperature processes. The behavior of bismuth metal particles, bismuth sulfide (Bi2S3)

  5. Bismuth toxicity in patients treated with bismuth iodoform paraffin packs.

    Science.gov (United States)

    Atwal, A; Cousin, G C S

    2016-01-01

    Bismuth is a heavy metal used in bismuth iodoform paraffin paste (BIPP) antiseptic dressings and in a number of other medical preparations. It can be absorbed systemically and cause toxicity. We report 2 cases of such neurotoxicity after it was used in operations on the jaws.

  6. Rapid confirmation of enzyme multiplied immunoassay technique (EMIT) cocaine positive urine samples by capillary gas-liquid chromatography/nitrogen phosphorus detection (GLC/NPD).

    Science.gov (United States)

    Verebey, K; DePace, A

    1989-01-01

    A rapid gas-liquid chromatographic (GLC) method was developed for the confirmation of benzoylecgonine (BE) positive urine samples screened by the enzyme multiplied immunoassay technique (EMIT) assay. The procedure is performed by solvent extraction of BE from 0.1 or 0.2 mL of urine, followed by an aqueous wash of the solvent and evaporation. The dried residue was derivatized with 50 microL of pentafluoropropionic anhydride and 25 microL of pentafluoropropropanol at 90 degrees C for 15 min. The derivatizing reagents were evaporated to dryness, and the derivatized BE, and cocaine if present, were reconstituted and injected into the gas chromatograph. The column was a 15-m by 0.2-mm fused silica capillary column, coated with 0.25 micron of DB-1, terminating in a nitrogen phosphorus detector (NPD). Cocaine and the pentafluoro BE derivatives retention times were 3.2 and 2.6 min, respectively. Nalorphine was used as reference or internal standard with a retention time of 4.78 min. The complete procedure can be performed in approximately 1.5 h. The EMIT cutoff between positive and negative urine samples is 300 ng/mL of BE. The lower limit of sensitivity of this method is 25 ng of BE extracted from urine. Validation studies resulted in confirmation of 101 out of 121 EMIT cocaine positive urine samples that could not be confirmed by thin-layer chromatography (TLC). This represents 84% confirmation efficiency.

  7. Bismuth(V) oxide and silver bismuthate as oxidizing agents for gas-chromatographic elemental microanalysis

    Energy Technology Data Exchange (ETDEWEB)

    Shvykin, A.Y.; Platonov, V.V.; Proskuryakov, V.P.; Chilachava, K.B.; Khmarin, E.M.; Kovtun, I.V. [Tolstoy State Pedag University, Tula (Russian Federation)

    2004-07-01

    Bismuth(V) oxide, silver bismuthate, and a mixture of bismuth(V) oxide with fine silver powder were studied as oxidizing additives in gas-chromatographic elemental microanalysis of readily combustible organic substances and coal.

  8. Bismuth ochers from San Diego Co., California

    Science.gov (United States)

    Schaller, W.T.

    1911-01-01

    The chief points brought out in this paper may be briefly summarized as follows: (1) The existence of natural Bi2O3 has not been established. (2) Natural bismite or bismuth ocher, when pure, is more probably a bismuth hydroxide. (3) The bismuth ochers from San Diego County, California, are either a bismuth hydroxide or bismuth vanadate, pucherite, or mixtures of these two. (4) Pucherite has been found noncrystallin and determined for the first time in the United States.

  9. Biosynthesis of bismuth nanoparticles using Serratia marcescens isolated from the Caspian Sea and their characterisation.

    Science.gov (United States)

    Nazari, P; Faramarzi, M A; Sepehrizadeh, Z; Mofid, M R; Bazaz, R D; Shahverdi, A R

    2012-06-01

    Today, synthesis of nanoparticles (NPs) using micro-organisms has been receiving increasing attention. In this investigation, a bismuth-reducing bacterium was isolated from the Caspian Sea in Northern Iran and was used for intracellular biosynthesis of elemental bismuth NPs. This isolate was identified as non-pigmented Serratia marcescens using conventional identification assays and the 16s rDNA fragment amplification method and used to prepare bismuth NPs. The biogenic bismuth NPs were released by liquid nitrogen and highly purified using an n-octanol water two-phase extraction system. Different characterisations of the purified NPs such as particle shapes, size and purity were carried out with different instruments. The energy-dispersive X-ray and X-ray diffraction (XRD) patterns demonstrated that the purified NPs consisted of only bismuth and are amorphous. In addition, the transmission electron micrograph showed that the small NPs formed larger aggregated NPs around <150 nm. Although the chemical syntheses of elemental bismuth NPs have been reported in the literature, the biological synthesis of elemental bismuth NPs has not been published yet. This is the first report to demonstrate a biological method for synthesising bismuth NPs and their purification with a simple solvent partitioning method.

  10. STED microscopy detects and quantifies liquid phase separation in lipid membranes using a new far-red emitting fluorescent phosphoglycerolipid analogue.

    Science.gov (United States)

    Honigmann, Alf; Mueller, Veronika; Hell, Stefan W; Eggeling, Christian

    2013-01-01

    We have developed a bright, photostable, and far-red emitting fluorescent phosphoglycerolipid analogue to probe diffusion characteristics of lipids in membranes. The lipid analogue consists of a saturated (C18) phosphoethanolamine and a hydrophilic far-red emitting fluorescent dye (KK114) that is tethered to the head group by a long polyethylenglycol linker. In contrast to reported far-red emitting fluorescent lipid analogues, this one partitions predominantly into liquid ordered domains of phase-separated ternary bilayers. We performed fluorescence correlation spectroscopy with a super-resolution STED microscope (STED-FCS) to measure the lateral diffusion of the new lipid analogue in the liquid ordered (Lo) and disordered (Ld) phase. On a mica support, we observed micrometer large phases and found that the lipid analogue diffuses freely on all tested spatial scales (40-250 nm) in both the Ld and Lo phase with diffusion coefficients of 1.8 microm2 s(-1) and 0.7 microm2 s(-1) respectively. This indicates that the tight molecular packing of the Lo phase mainly slows down the diffusion rather than causing anomalous sub-diffusion. The same ternary mixture deposited on acid-cleaned glass forms Lo nanodomains of analogue into the nano-domains, where diffusion is slowed down. Our results suggest that STED-FCS in combination with a Lo-partitioning fluorescent lipid analogue can directly probe the presence of Lo nano-domains, which in the future should allow the study of potential lipid rafts in live-cell membranes.

  11. Energetics of bismuth vanadate

    Energy Technology Data Exchange (ETDEWEB)

    Nagabhushana, G.P.; Tavakoli, A.H.; Navrotsky, A., E-mail: anavrotsky@ucdavis.edu

    2015-05-15

    Bismuth vanadate has gained considerable interest as a photoanode for water splitting reactions under visible light. It exists in four different polymorphs, out of which three of them have been synthesized. Thermodynamic properties of these three polymorphs are investigated using high temperature oxide melt solution calorimetry. The monoclinic scheelite phase which exhibits photocatalytic activity under visible light is found to be the most stable polymorph, followed by tetragonal scheelite which exhibits activity under UV light. The photocatalytically inactive tetragonal zircon form is found to be the least stable polymorph. The small difference in enthalpy of formation between the two scheelite structures (−8 kJ/mol) is in accord with the reversibility of the transformation between them and the larger difference between the most stable monoclinic phase and the least stable tetragonal zircon phase (−23 kJ/mol) is in accord with the irreversible (monoclinic→tetragonal zircon) phase transformation. - Graphical abstract: Schematic representation of polymorphic transitions in BiVO{sub 4} along with their formation enthalpies. - Highlights: • Bismuth vanadate crystallizes in three different polymorphs. • High temperature calorimetric measurements were made to determine their formation enthalpies. • Enthalpy of formation decreases in the order BV-ms→BV-ts→BV-tz. • Photocatalytically active monoclinic-BiVO{sub 4} was found to be the most stable polymorph.

  12. Polycyclic Aromatic Hydrocarbons in Fine Particulate Matter Emitted from Burning Kerosene, Liquid Petroleum Gas, and Wood Fuels in Household Cookstoves

    Science.gov (United States)

    This study measured polycyclic aromatic hydrocarbon (PAH) composition in particulate matter emissions from residential cookstoves. A variety of fuel and cookstove combinations were examined, including: (i) liquid petroleum gas (LPG), (ii) kerosene in a wick stove, (iii) wood (10%...

  13. Energetics of bismuth vanadate

    Science.gov (United States)

    Nagabhushana, G. P.; Tavakoli, A. H.; Navrotsky, A.

    2015-05-01

    Bismuth vanadate has gained considerable interest as a photoanode for water splitting reactions under visible light. It exists in four different polymorphs, out of which three of them have been synthesized. Thermodynamic properties of these three polymorphs are investigated using high temperature oxide melt solution calorimetry. The monoclinic scheelite phase which exhibits photocatalytic activity under visible light is found to be the most stable polymorph, followed by tetragonal scheelite which exhibits activity under UV light. The photocatalytically inactive tetragonal zircon form is found to be the least stable polymorph. The small difference in enthalpy of formation between the two scheelite structures (-8 kJ/mol) is in accord with the reversibility of the transformation between them and the larger difference between the most stable monoclinic phase and the least stable tetragonal zircon phase (-23 kJ/mol) is in accord with the irreversible (monoclinic→tetragonal zircon) phase transformation.

  14. Mineral resource of the month: bismuth

    Science.gov (United States)

    Carlin, James F.

    2006-01-01

    Bismuth compounds are most known for their soothing effects on the stomach, wounds and sores. These properties make the compounds an essential part of many medicinal and cosmetic preparations, which until 1930 accounted for about 90 percent of the bismuth used. The subsequent development of low-melting alloys and chemical catalysts containing bismuth, as well as its use as an additive to casting alloys, has resulted in a wider variety of industrial applications for bismuth.

  15. Modular Lead-Bismuth Fast Reactors in Nuclear Power

    OpenAIRE

    Vladimir Petrochenko; Georgy Toshinsky

    2012-01-01

    On the basis of the unique experience of operating reactors with heavy liquid metal coolant–eutectic lead-bismuth alloy in nuclear submarines, the concept of modular small fast reactors SVBR-100 for civilian nuclear power has been developed and validated. The features of this innovative technology are as follows: a monoblock (integral) design of the reactor with fast neutron spectrum, which can operate using different types of fuel in various fuel cycles including MOX fuel in a self-providing...

  16. Synthesis of high intensity green emitting (Ba,Sr)SiO4:Eu2+ phosphors through cellulose assisted liquid phase precursor process

    Science.gov (United States)

    Humayoun, Usama Bin; Song, Young-Hyun; Lee, MinJi; Masato, Kakihana; Abe, Hiroshi; Toda, Kenji; Sato, Yasushi; Masaki, Takaki; Yoon, Dae-Ho

    2016-01-01

    Green emitting phosphor (Ba1-x,Sr1-x)SiO4:2xEu2+, x = 0.03, 0.05, 0.1, and 0.15 were synthesized through a Liquid Phase Precursor Process (LPP). Liquid phase precursor method is reported to result in phosphors with markedly increased emission intensities compared to other synthesis methods. Here microcrystalline cellulose (MCC) and hydroxypropyl cellulose (HPC) templates were studied to achieve high efficiency green phosphors. The phase formation was investigated by XRD analysis which showed the conformation of the Ba2SiO4 (JCPDS card number 761631) phase. The obtained samples exhibited broad excitation spectra with maximum at 430 nm and a green emission centered around 520 nm. An optimized dopant concentration was selected and the effect of two different types of cellulose, i.e. MCC and HPC templates on the emission properties was considered. It was found that the samples synthesized using HPC and fired at 1050 °C under a reducing atmosphere, showed a high intensity of almost 2 times that of the MCC sample. Further experiments were conducted by varying viscosity, particle weight, and molecular weight of the HPC template. It was found that the green emission from the (Ba,Sr)SiO4:Eu2+ increased with the increase in viscosity and molecular weight of the template.

  17. Absorbance detector for high performance liquid chromatography based on a deep-UV light-emitting diode at 235nm.

    Science.gov (United States)

    da Silveira Petruci, João Flavio; Liebetanz, Michael G; Cardoso, Arnaldo Alves; Hauser, Peter C

    2017-08-25

    In this communication, we describe a flow-through optical absorption detector for HPLC using for the first time a deep-UV light-emitting diode with an emission band at 235nm as light source. The detector is also comprised of a UV-sensitive photodiode positioned to enable measurement of radiation through a flow-through cuvette with round aperture of 1mm diameter and optical path length of 10mm, and a second one positioned as reference photodiode; a beam splitter and a power supply. The absorbance was measured and related to the analyte concentration by emulating the Lambert-Beer law with a log-ratio amplifier circuitry. This detector showed noise levels of 0.30mAU, which is comparable with our previous LED-based detectors employing LEDs at 280 and 255nm. The detector was coupled to a HPLC system and successfully evaluated for the determination of the anti-diabetic drugs pioglitazone and glimepiride in an isocratic separation and the benzodiazepines flurazepam, oxazepam and clobazam in a gradient elution. Good linearities (r>0.99), a precision better than 0.85% and limits of detection at sub-ppm levels were achieved. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Overview of the use of ATHENA for thermal-hydraulic analysis of systems with lead-bismuth coolant

    Energy Technology Data Exchange (ETDEWEB)

    C. B. Davis; A. S. Shieh

    2000-04-02

    The INEEL and MIT are investigating the suitability of lead-bismuth cooled fast reactor for producing low-cost electricity as well as for actinide burning. This paper is concerned with the general area of thermal-hydraulics of lead-bismuth cooled reactors. The ATHENA code is being used in the thermal-hydraulic design and analysis of lead-bismuth cooled reactors. The ATHENA code was reviewed to determine its applicability for simulating lead-bismuth cooled reactors. Two modifications were made to the code as a result of this review. Specifically, a correlation to represent heat transfer from rod bundles to a liquid metal and a void correlation based on data taken in a mixture of lead-bismuth and steam were added the code. The paper also summarizes the analytical work that is being performed with the code and plans for future analytical work.

  19. Overview of the Use of ATHENA for Thermal-Hydraulic Analysis of Systems with Lead-Bismuth Coolant

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Cliff Bybee; Shieh, Arthur Shan Luk

    2000-04-01

    The INEEL and MIT are investigating the suitability of lead-bismuth cooled fast reactor for producing low-cost electricity as well as for actinide burning. This paper is concerned with the general area of thermal-hydraulics of lead-bismuth cooled reactors. The ATHENA code is being used in the thermal-hydraulic design and analysis of lead-bismuth cooled reactors. The ATHENA code was reviewed to determine its applicability for simulating lead-bismuth cooled reactors. Two modifications were made to the code as a result of this review. Specifically, a correlation to represent heat transfer from rod bundles to a liquid metal and a void correlation based on data taken in a mixture of lead-bismuth and steam were added the code. The paper also summarizes the analytical work that is being performed with the code and plans for future analytical work.

  20. Coordination chemistry of the sup 212 Pb/ sup 212 Bi nuclear transformation: Alpha-emitting radiopharmaceuticals

    Energy Technology Data Exchange (ETDEWEB)

    Parks, N.J.; Harris, W.R.; Keen, C.L.; Cooper, S.R.

    1992-07-01

    Subdivisions of this project are: (a) the synthesis of prototypical thiolate and dithiocarbamate based hexacoordinate complexes, (b) radiochemical engineering for generation of no-carrier-added lead and bismuth radioelements, (c) the first isolation of bismuth-binding proteins from in vivo studies with cyclotron produced {sup 205/206}Bi tracer, and (d) initial development of transport mechanisms for the intracellular radiobiological study of alpha emitting bismuth, and (e) the initiation of chemical equilibrium studies and biochemical pathways with cyclotron-produced, no-carrier-added, {sup 203}Pb (T{sub 1/2} = 51 hr).

  1. Rapid screening and analysis of alpha- and gamma-emitting radionuclides in liquids using a single sample preparation procedure.

    Science.gov (United States)

    Parsa, Bahman; Henitz, James B; Carter, Jennifer A

    2011-02-01

    A multifaceted radiochemical testing procedure has been developed to analyze a large number of liquid samples and measure a wide range of radionuclides in a short period of time. This method involves a single, unique and fast sample preparation procedure and allows sequential/concurrent determination of analytes with accuracy and precision. The same prepared sample can be selectively analyzed by gross alpha counting, gamma-ray spectroscopy, and alpha spectroscopy. This method is especially attractive in radiological emergency events where analytical data will be needed urgently as a basis for protective action. Given the simplicity and rapidity of the method, it may be suitable for field portable laboratories, which could save time and the cost associated with the transit of samples to a fixed laboratory. A 100 mL aliquot of sample was spiked with ¹³³Ba and ⁵⁹Fe tracers and subjected to a chemical separation procedure using a combined BaSO4 and Fe(OH)3 co-precipitation scheme. Then, the gross alpha-particle activity of the prepared sample was measured with a low-background gas-proportional counter, followed by the analysis of its photon-emitters using a gamma-ray spectroscopy system with high-purity intrinsic Ge detectors. Gamma-ray determination of ¹³³Ba and ⁵⁹Fe tracers was used to assess the chemical recoveries of BaSO4 and Fe(OH)3 fractions, respectively. Selectivity of the radionuclides for co-precipitation with either BaSO4 or Fe(OH)3 components was also investigated. Alpha mass-efficiency curves were derived using ²³⁰Th and ²⁴¹Am standards as alpha-calibration sources. Various mixtures of radionuclides, including ⁵⁴Mn, ⁵⁷Co, ⁶⁰Co, ⁸⁵Sr, ⁸⁸Y, ¹⁰⁹Cd, ¹¹³Sn, ¹³⁷Cs, ¹³⁹Ce, ²⁰³Hg, ²⁰⁹Po, ²²⁶Ra, ²²⁸Ra, ²³⁰Th, ²⁴¹Am, and natural uranium were used in this study. Most were quantitatively assayed with high chemical recoveries. Alpha-isotope identification and assessment of the prepared

  2. Comparative Study of Semiconductors Bismuth Iodate, Bismuth Triiodide and Bismuth Trisulphide Crystals

    Directory of Open Access Journals (Sweden)

    T.K. Patil

    2012-12-01

    Full Text Available In the present investigation, crystals of Bismuth Iodate[Bi(IO33], Bismuth Iodide[BiI3] and Bismuth- Tri Sulphide [Bi2S3] were grown by a simple gel technique using single diffusion method. The optimum growth conditions were established by varying various parameters such as pH of gel solution, gel concentration, gel setting time, concentration of reactant etc. Gel was prepared by mixing sodium meta silicate (Na2SiO35H2O, glacial acetic acid (CH3COOH and supernant bismuth chloride (BiCl3 at pH value 4.4 and transferred in glass tube of diameter 2.5 cm and 25 cm in length. The mouth of test tube was covered by cotton plug and kept it for the setting. After setting the gel, it was left for aging. After 13 days duration the second supernant K(IO3, KI3 and H2S water gas solution was poured over the set gel by using pipette then it was kept undisturbed. After 72 hours of pouring the second supernatant, the small nucleation growth was observed at below the interface of gel. The good quality crystals of [Bi(IO33], [BiI3] and [Bi2S3] were grown. These grown crystals were characterized by XRD, FTIR, Chemical Analysis and Electrical Conductivity.

  3. Bismuth nanoparticles synthesized by laser ablation in lubricant oils for tribological tests

    Energy Technology Data Exchange (ETDEWEB)

    Flores-Castañeda, M., E-mail: mar.floc@hotmail.com [Universidad Autónoma del Estado de México, Av. Instituto Literario No. 100, Oriente Col. Centro, Toluca, Estado de México C.P. 50000, México (Mexico); Instituto Nacional de Investigaciones Nucleares, Carretera México-Toluca s/n, La Marquesa, Ocoyoacac, Edo. de México C.P. 52750, México (Mexico); Camps, E. [Instituto Nacional de Investigaciones Nucleares, Carretera México-Toluca s/n, La Marquesa, Ocoyoacac, Edo. de México C.P. 52750, México (Mexico); Camacho-López, M. [Universidad Autónoma del Estado de México, Av. Instituto Literario No. 100, Oriente Col. Centro, Toluca, Estado de México C.P. 50000, México (Mexico); Muhl, S. [Instituto de Investigación en Materiales (UNAM), Circuito Exterior, Ciudad Universitaria, Coyoacán, 04510 México, D.F., México (Mexico); and others

    2015-09-15

    Highlights: • Bismuth nanoparticles have been obtained by laser ablation of solids in liquids. • The technique allows controlling the size and concentration of the samples. • Bi np’s in base oils can improve the tribological characteristics of the lubricant. - Abstract: The improvement of the tribological properties of mineral base oils through the addition of bismuth nanoparticles as an additive, together with the idea of obtaining lubricants free of heavy metals, was evaluated. Bismuth nanoparticles were produced directly in the heavy and light viscosity mineral base oils (BS900 and BS6500) using the technique of laser ablation of solids immersed in liquids. Transmission electron microscopy measurements showed the presence of pure bismuth nanoparticles. Small Angle X-ray Scattering (SAXS) measurements showed that the average size of the nanoparticles was between 7 and 65 nm depending on the experimental conditions used. The tribological properties of the base oil with the bismuth nanoparticles additives were evaluated using a four-ball tester. Tests were performed using the base oil with and without Bi nanoparticles. It was observed that the coefficient of friction of the oil decrease with an increasing concentration of the nanoparticles. The results also showed that the wear rate was reduced when the Bi nanoparticle additives were used.

  4. Hydrothermal synthesis of bismuth germanium oxide

    Energy Technology Data Exchange (ETDEWEB)

    Boyle, Timothy J.

    2016-12-13

    A method for the hydrothermal synthesis of bismuth germanium oxide comprises dissolving a bismuth precursor (e.g., bismuth nitrate pentahydrate) and a germanium precursor (e.g., germanium dioxide) in water and heating the aqueous solution to an elevated reaction temperature for a length of time sufficient to produce the eulytite phase of bismuth germanium oxide (E-BGO) with high yield. The E-BGO produced can be used as a scintillator material. For example, the air stability and radioluminescence response suggest that the E-BGO can be employed for medical applications.

  5. Bismuth absorption from sup 205 Bi-labelled pharmaceutical bismuth compounds used in the treatment of peptic ulcer disease

    Energy Technology Data Exchange (ETDEWEB)

    Dresow, B.; Fischer, R.; Gabbe, E.E.; Wendel, J.; Heinrich, H.C. (Eppendorf University Hospital, Hamburg (Germany))

    1992-04-01

    The absorption of bismuth from five {sup 205}Bi-labelled pharmaceutically used bismuth compounds was studied in man. From single oral doses of all compounds under investigation only <0.1% bismuth was absorbed and excreted with the urine. A significantly higher absorption was observed from the colloidal bismuth subcitrate and the basic bismuth gallate than from the basic bismuth salicylate, nitrate and aluminate. No retention of bismuth in the whole body was found from the single dose experiment. The biologic fast-term half-lives of absorbed bismuth were calculated to be 0.12 and 1.5 days. 14 refs., 2 figs., 1 tab.

  6. Ranitidine bismuth citrate: A review

    Directory of Open Access Journals (Sweden)

    N Chiba

    2001-01-01

    Full Text Available Recognition of the relationship between Helicobacter pylori infection and the development of gastroduodenal disease has increased greatly in recent years. To avoid complications of H pylori infection, such as the development of recurrent duodenal and gastric ulcers, effective therapies are required for eradication of the infection. This article reviews ranitidine bismuth citrate (RBC, a novel complex of ranitidine, bismuth and citrate, which was developed specifically for the purpose of eradicating H pylori. Dual therapy with RBC in combination with clarithromycin for 14 days yields eradication rates of 76%. Triple therapy bid for one week with a proton pump inhibitor, clarithromycin and either amoxicillin or a nitroimidazole (tinidazole or metronidazole is advocated as the treatment of choice for H pylori eradication. Analogous regimens with RBC in place of proton pump inhibitors show effective eradication rates in comparative studies and with pooled data. RBC, used alone or in combination with other antibiotics, appears to be a safe and effective drug for the treatment of H pylori infection. Bismuth levels do not appear to rise to toxic levels.

  7. In vitro cytotoxicity of surface modified bismuth nanoparticles.

    Science.gov (United States)

    Luo, Yang; Wang, Chaoming; Qiao, Yong; Hossain, Mainul; Ma, Liyuan; Su, Ming

    2012-10-01

    This paper describes in vitro cytotoxicity of bismuth nanoparticles revealed by three complementary assays (MTT, G6PD, and calcein AM/EthD-1). The results show that bismuth nanoparticles are more toxic than most previously reported bismuth compounds. Concentration dependent cytotoxicities have been observed for bismuth nanoparticles and surface modified bismuth nanoparticles. The bismuth nanoparticles are non-toxic at concentration of 0.5 nM. Nanoparticles at high concentration (50 nM) kill 45, 52, 41, 34 % HeLa cells for bare nanoparticles, amine terminated bismuth nanoparticles, silica coated bismuth nanoparticles, and polyethylene glycol (PEG) modified bismuth nanoparticles, respectively; which indicates cytotoxicity in terms of cell viability is in the descending order of amine terminated bismuth nanoparticles, bare bismuth nanoparticles, silica coated bismuth nanoparticles, and PEG modified bismuth nanoparticles. HeLa cells are more susceptible to toxicity from bismuth nanoparticles than MG-63 cells. The simultaneous use of three toxicity assays provides information on how nanoparticles interact with cells. Silica coated bismuth nanoparticles can damage cellular membrane yet keep mitochondria less influenced; while amine terminated bismuth nanoparticles can affect the metabolic functions of cells. The findings have important implications for caution of nanoparticle exposure and evaluating toxicity of bismuth nanoparticles.

  8. Structural investigations of bismuth lead borosilicate glasses under the influence of gamma irradiation through ultrasonic studies

    Science.gov (United States)

    Bootjomchai, Cherdsak; Laopaiboon, Jintana; Laopaiboon, Raewat

    2012-04-01

    The ultrasonic velocity measurements for different compositions of irradiated bismuth lead borosilicate glasses xBi2O3-(50-x)PbO-20B2O3-30SiO2 (x=2, 4, 6, 8, and 10 mol.%) were performed at room temperature using pulse-echo technique. Densities of glass samples were measured by Archimedes' principle using n-hexane as the immersion liquid. The results from the studies show that ultrasonic velocity, elastic moduli, Poisson's ratio, microhardness, and the Debye temperature increase with increasing bismuth oxide content and increasing gamma-radiation dose (3-12 Gy).

  9. Microwave-assisted synthesis of bismuth oxide

    Directory of Open Access Journals (Sweden)

    Eva Bartonickova

    2007-12-01

    Full Text Available Single phase and ultrafine bismuth oxide was synthesized via microwave-assisted hydrothermal synthesis. The effect of reaction parameters (temperature/pressure and pH on the product phase composition and morphology was discussed. The transformation of bismuth hydroxide into bismuth oxide was controlled by pH value and it was accelerated by time and temperature. The phase composition of reaction products was strongly dependent on pH value. The amorphous products were obtained at acidic pH conditions and the crystalline single phase product α-Bi2O3 phase was obtained at pH ≥12. The particle size was reduced from micrometric to nanometric size in the presence of a chelating agent. The bismuth hydroxides into bismuth oxides transformation mechanism, consisting in polycondensation ofBi–OH bounds to Bi–O–Bi bridges and crystallization of Bi2O3, was proposed.

  10. Coordination chemistry of the {sup 212}Pb/{sup 212}Bi nuclear transformation: Alpha-emitting radiopharmaceuticals. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Parks, N.J.; Harris, W.R.; Keen, C.L.; Cooper, S.R.

    1992-07-01

    Subdivisions of this project are: (a) the synthesis of prototypical thiolate and dithiocarbamate based hexacoordinate complexes, (b) radiochemical engineering for generation of no-carrier-added lead and bismuth radioelements, (c) the first isolation of bismuth-binding proteins from in vivo studies with cyclotron produced {sup 205/206}Bi tracer, and (d) initial development of transport mechanisms for the intracellular radiobiological study of alpha emitting bismuth, and (e) the initiation of chemical equilibrium studies and biochemical pathways with cyclotron-produced, no-carrier-added, {sup 203}Pb (T{sub 1/2} = 51 hr).

  11. Bismuth ions are metabolized into autometallographic traceable bismuth-sulphur quantum dots

    Directory of Open Access Journals (Sweden)

    M Stoltenberg

    2009-06-01

    Full Text Available Bismuth – sulphur quantum dots can be silver enhanced by autometallography (AMG. In the present study, autometallographic silver enhanced bismuth-sulphur nanocrystals were isolated from unfixed cryo-sections of kidneys and livers of rats exposed to bismuth (Bi207 subnitrate. After being subjected to AMG all the organic material was removed by sonication and enzymatic digestion and the silver enhanced Bi- S quantum dots spun down by an ultracentrifuge and analyzed by scintillation. The analysis showed that the autometallographic technique traces approximately 94% of the total bismuth. This implies that the injected bismuth is ultimately captured in bismuthsulphur quantum dots, i.e., that Bi-S nanocrystals are the end product of bismuth metabolism

  12. Study of iron structure stability in high temperature molten lead-bismuth eutectic with oxygen injection using molecular dynamics simulation

    Energy Technology Data Exchange (ETDEWEB)

    Arkundato, Artoto [Physics Department, Faculty of Mathematical and Natural Sciences, Jember University, Jl. Kalimantan 37 Jember (Indonesia); Su' ud, Zaki [Physics Department, Faculty of Mathematical and Natural Sciences, Bandung Institute of Technology, Jl. Ganesha 10, Bandung (Indonesia); Sudarko [Chemistry Department, Faculty of Mathematical and Natural Sciences, Jember University, Jl. Kalimantan 37 Jember (Indonesia); Shafii, Mohammad Ali [Physics Department, Faculty of Mathematical and Natural Sciences, Andalas University, Padang (Indonesia); Celino, Massimo [ENEA, CR Casaccia, Via Anguillarese 301, Rome (Italy)

    2014-09-30

    Corrosion of structural materials in high temperature molten lead-bismuth eutectic is a major problem for design of PbBi cooled reactor. One technique to inhibit corrosion process is to inject oxygen into coolant. In this paper we study and focus on a way of inhibiting the corrosion of iron using molecular dynamics method. For the simulation results we concluded that effective corrosion inhibition of iron may be achieved by injection 0.0532 wt% to 0.1156 wt% oxygen into liquid lead-bismuth. At this oxygen concentration the structure of iron material will be maintained at about 70% in bcc crystal structure during interaction with liquid metal.

  13. Preparation of Bismuth Oxide Photocatalyst and Its Application in White-light LEDs

    Directory of Open Access Journals (Sweden)

    Yen-Chang Chu

    2013-01-01

    Full Text Available Bismuth oxide photocatalysts were synthesized and coated on the front surface of phosphor-converted white light-emitting diodes to produce a safe and environmentally benign lighting source. Bismuth oxide photocatalyst powders were synthesized with a spray pyrolysis method at 500°C, 600°C, 700°C, and 800°C. Using the absorption spectrum in the blue and UV regions of the bismuth oxide photocatalysts, the blue light and UV leakage problems of phosphor-converted white LEDs can be significantly reduced. The experimental results showed that bismuth oxide photocatalyst synthesized at 700°C exhibited the most superior spectrum inhibiting ability. The suppressed ratio reached 52.33% in the blue and UV regions from 360 to 420 nm. Related colorimetric parameters and the photocatalyst decomposition ability of fabricated white-light LEDs were tested. The CIE chromaticity coordinates (x,y were (0.349, 0.393, and the correlated color temperature was 4991 K. In addition, the coating layer of photocatalyst can act as an air purifier and diffuser to reduce glare. A value of 66.2±0.60 ppmv of molecular formaldehyde gas can be decomposed in 120 mins.

  14. Electrochemical Light-Emitting Gel

    Directory of Open Access Journals (Sweden)

    Nobuyuki Itoh

    2010-06-01

    Full Text Available Light-emitting gel, a gel state electroluminescence material, is reported. It is composed of a ruthenium complex as the emitter, an ionic liquid as the electrolyte, and oxide nanoparticles as the gelation filler. Emitted light was produced via electrogenerated chemiluminescence. The light-emitting gel operated at low voltage when an alternating current was passed through it, regardless of its structure, which is quite thick. The luminescence property of the gel is strongly affected by nanoparticle materials. TiO2 nanoparticles were a better gelation filler than silica or ZnO was, with respect to luminescence stability, thus indicating a catalytic effect. It is demonstrated that the light-emitting gel device, with quite a simple fabrication process, flashes with the application of voltage.

  15. Compatibility tests on steels in molten lead and lead-bismuth

    Energy Technology Data Exchange (ETDEWEB)

    Fazio, C. E-mail: concetta@netbra.brasimone.enea.it; Benamati, G.; Martini, C.; Palombarini, G

    2001-07-01

    The compatibility of steels with liquid lead and liquid lead-bismuth is a critical issue for the development of accelerator-driven system (ADS). In this work the results of a set of preliminary tests carried out in stagnant molten lead at 737 K and in lead-bismuth at 573, 673 and 749 K are summarised. The tests were conducted for 700, 1200, 1500 and 5000 h. Three steels were tested: two martensitic steels (mod. F82H and MANET II) and one austenitic steel (AISI 316L). The martensitic steels underwent oxidation phenomena at the higher testing temperature, due to oxygen dissolved in the melts. At a lower test temperature (573 K) and higher exposure time (5000 h) the oxidation rate of the martensitic steel seems to be lower and the developed oxide layer protective against liquid metal corrosion. The austenitic steel, in turn, exhibited an acceptable resistance to corrosion-oxidation under the test conditions.

  16. Preparation of Strontium Bismuth Tantalum (SBT) Fine Powder by Sol-Gel Process Using Bismuth Subnitrate as Bismuth Source

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Strontium bismuth tantalum (SBT) fine power was prepared by Sol-Gel method. Pentaethoxy tantalum, strontium acetate and bismuth subnitrate were used as raw materials, and were dissolved in proper order in ethylene glycol to form transparent sol. The mixed precursor was dried at 80°C and annealed at 800°C for 1 h. Crystallized nanometer sized SBT fine powder was obtained and characterized by XRD.

  17. Extractive Spectrophotometric Determination of Bismuth(III in Water Using Some Ion Pairing Reagents

    Directory of Open Access Journals (Sweden)

    Abdulaziz S. Bashammakh

    2011-01-01

    Full Text Available Two novel and low cost liquid-liquid extraction methods for the separation of bismuth(III at trace level from aqueous medium have been developed. The two methods were based upon the formation of yellow colored ternary complex ion associates of tetraiodobismuth(III complex anion, BiI4- with the ion-pairing reagent 2,3,5-tetraphenyltetrazoliumchloride (Tz+.Cl– and 1, 10 phenanthroline (Phen in sulfuric acid medium. The effect of various parameters e.g. pH, organic solvent, shaking time, etc. on the preconcentration of bismuth(III from the aqueous media by the reagent was investigated. The developed colored complex ion associates [Tz+.BiI4-] and [Phen+.BiI4-] were extracted quantitatively into acetone-chloroform (1:1v/v and methyliso- butylketone (MIBK, respectively. The compositions of the formed complex ion associates [Tz+.BiI4-] and [Phen+.BiI4-] were determined by the Job's method at 500 and 490 nm, respectively. The plots of bismuth(III concentration (0-17 μg mL-1 versus absorbance of the associates at 500 and 490 nm were linear with good correlation coefficient (R2=0.998. The developed method of the ion associate [Tz+.BiI4-] two methods was applied successfully for the analysis of bismuth in water.

  18. Electrochemical properties of porous bismuth electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Romann, T., E-mail: tavo.romann@ut.e [Institute of Chemistry, University of Tartu, Ravila 14A, 50411 Tartu (Estonia); Lust, E. [Institute of Chemistry, University of Tartu, Ravila 14A, 50411 Tartu (Estonia)

    2010-08-01

    The properties of Bi surfaces with different roughnesses were characterized by electron microscopy, cyclic voltammetry, and impedance spectroscopy. Two different strategies were used for preparation of porous bismuth layers onto Bi microelectrode surface in aqueous 0.1 M LiClO{sub 4} solution. Firstly, treatment at potential E < -2 V (vs. Ag|AgCl in sat. KCl) has been applied, resulting in bismuth hydride formation and decomposition into Bi nanoparticles which deposit at the electrode surface. Secondly, porous Bi layer was prepared by anodic dissolution (E = 1 V) of bismuth electrode followed by fast electroreduction of formed Bi{sup 3+} ions at cathodic potentials E = -2 V. The nanostructured porous bismuth electrode, with surface roughness factor up to 220, has negligible frequency dispersion of capacitance and higher hydrogen evolution overvoltage than observed for smooth Bi electrodes.

  19. Thermoelectric properties of pressed bismuth nanoparticles

    Science.gov (United States)

    Hostler, Stephen R.; Qu, Yu Qiao; Demko, Michael T.; Abramson, Alexis R.; Qiu, Xiaofeng; Burda, Clemens

    2008-03-01

    Theory predicts a substantial increase in the dimensionless figure of merit as the dimensionality and characteristic size of a material are decreased. We explore the use of bismuth nanoparticles pressed into pellets as potential increased efficiency thermoelectric materials. The figure of merit of these pellets is determined by independently measuring the electrical conductivity, thermal conductivity and Seebeck coefficient. The results from the nanoparticle sample are compared to microparticle-based samples. Both sample types show a slight reduction in thermal conductivity relative to bulk bismuth and a Seebeck coefficient near or slightly larger in magnitude than bulk bismuth. These changes are dwarfed by a hundred-fold decrease in the electrical conductivity due to porosity and an oxide layer on the particles. The low conductivity leads to figures of merit at least two orders of magnitude smaller than bulk bismuth. Oxide layer removal and reduced pellet porosity will be required to increase the figure of merit.

  20. High precision hyperfine measurements in Bismuth challenge bound-state strong-field QED

    Science.gov (United States)

    Ullmann, Johannes; Andelkovic, Zoran; Brandau, Carsten; Dax, Andreas; Geithner, Wolfgang; Geppert, Christopher; Gorges, Christian; Hammen, Michael; Hannen, Volker; Kaufmann, Simon; König, Kristian; Litvinov, Yuri A.; Lochmann, Matthias; Maaß, Bernhard; Meisner, Johann; Murböck, Tobias; Sánchez, Rodolfo; Schmidt, Matthias; Schmidt, Stefan; Steck, Markus; Stöhlker, Thomas; Thompson, Richard C.; Trageser, Christian; Vollbrecht, Jonas; Weinheimer, Christian; Nörtershäuser, Wilfried

    2017-05-01

    Electrons bound in highly charged heavy ions such as hydrogen-like bismuth 209Bi82+ experience electromagnetic fields that are a million times stronger than in light atoms. Measuring the wavelength of light emitted and absorbed by these ions is therefore a sensitive testing ground for quantum electrodynamical (QED) effects and especially the electron-nucleus interaction under such extreme conditions. However, insufficient knowledge of the nuclear structure has prevented a rigorous test of strong-field QED. Here we present a measurement of the so-called specific difference between the hyperfine splittings in hydrogen-like and lithium-like bismuth 209Bi82+,80+ with a precision that is improved by more than an order of magnitude. Even though this quantity is believed to be largely insensitive to nuclear structure and therefore the most decisive test of QED in the strong magnetic field regime, we find a 7-σ discrepancy compared with the theoretical prediction.

  1. Gravimetric Analysis of Bismuth in Bismuth Subsalicylate Tablets: A Versatile Quantitative Experiment for Undergraduate Laboratories

    Science.gov (United States)

    Davis, Eric; Cheung, Ken; Pauls, Steve; Dick, Jonathan; Roth, Elijah; Zalewski, Nicole; Veldhuizen, Christopher; Coeler, Joel

    2015-01-01

    In this laboratory experiment, lower- and upper-division students dissolved bismuth subsalicylate tablets in acid and precipitated the resultant Bi[superscript 3+] in solution with sodium phosphate for a gravimetric determination of bismuth subsalicylate in the tablets. With a labeled concentration of 262 mg/tablet, the combined data from three…

  2. Effect of phase stability degradation of bismuth on sensor characteristics of nano-bismuth fixed electrode.

    Science.gov (United States)

    Lee, Gyoung-Ja; Kim, Chang Kyu; Lee, Min Ku; Rhee, Chang Kyu

    2010-12-15

    Effect of phase stability degradation of bismuth on sensor characteristics of nano-bismuth fixed electrode has been investigated using square-wave anodic stripping voltammetry technique, scanning electron microscopy (SEM) and X-ray diffraction (XRD) spectroscopy. From the analyses of square-wave anodic stripping voltammograms (SWASV) repetitively measured on the nano-bismuth fixed electrode, it was found that the oxidation peak currents dropped by 81%, 68% and 59% for zinc, cadmium and lead, respectively, after the 100th measurement (about 400 min of operation time). The sphere bismuth nanoparticles gradually changed to the agglomerates with petal shape as the operation time increased. From the analyses of SEM images and XRD patterns, it is confirmed that the oxidation of Bi into BiOCl/Bi(2)O(2)CO(3) and the agglomeration of bismuth nanoparticles caused by the phase change decrease a reproducibility of the stripping voltammetric response. Moreover, most of the bismuth becomes BiOCl at pH 3.0 and bismuth hydroxide, Bi(OH)(3) at pH 7.0, which results in a significant decrease in sensitivity of the nano-bismuth fixed electrode.

  3. 铋含量对铅铋合金表面张力的影响分析%Influence of Bismuth Content on Surface Tension of Lead-bismuth Alloy

    Institute of Scientific and Technical Information of China (English)

    王龙; 徐敬尧; 徐刚; 刘少军; 黄群英

    2013-01-01

    Liquid lead-bismuth alloy has been considered as the potential candidates for the liquid spallation targets and the coolant of accelerator driven sub-critical system (ADS ) . Surface tension is one of the important thermal and physical properties parameters of lead-bismuth alloy , and temperature and chemical composition are important influence factors of surface tension . In this paper , the surface tension of liquid lead-bismuth alloy was measured by sessile drop (SD ) method . The results indicate that the surface tension of lead-bismuth alloy firstly increases and then decreases with the increase of the test temperature ,and the surface tension for low test temperature is significantly small .At the same temperature ,the surface tension of lead-bismuth alloy decreases with the increase of bismuth content , and segregation of bismuth onto the surface of molten lead-bismuth alloy is a key factor leading to the smaller surface tension .T he results of this study provide basic reference for composition optimization of lead-bismuth alloy ,w hich is of great significance for the development of spallation targets and the coolant materials of accelerated driven sub-critical system .%液态铅铋合金是加速器驱动的次临界系统(ADS )中散裂靶兼冷却剂的主要候选材料。表面张力是液态铅铋合金的重要热物性参数之一,而温度和化学组成是影响表面张力的关键因素。本文采用静滴法测量了5种不同成分铅铋合金的表面张力。实验结果显示:在测试温度范围内,铅铋合金的表面张力均随温度的升高先增大后减小,且在低温区表面张力非常小;相同温度下,铅铋合金的表面张力随Bi含量的增大逐渐降低,其中Bi的表面偏聚是导致其变小的重要因素之一。本研究结果为铅铋合金的成分优化提供了基本参考,对发展ADS散裂靶和冷却剂材料具有重要意义。

  4. Thermal degradation of ultrabroad bismuth NIR luminescence in bismuth-doped tantalum germanate laser glasses.

    Science.gov (United States)

    Wang, Liping; Zhao, Yanqi; Xu, Shanhui; Peng, Mingying

    2016-04-01

    Because of ultra-broadband luminescence in 1000-1700 nm and consequent applications in fiber amplifier and lasers in the new spectral range where traditional rare earth cannot work, bismuth-doped laser glasses have received rising interest recently. For long-term practical application, thermal degradation must be considered for the glasses. This, however, has seldom been investigated. Here we report the thermal degradation of bismuth-doped germanate glass. Heating and cooling cycle experiments at high temperature reveal strong dependence of the thermal degradation on glass compositions. Bismuth and tantalum lead to the reversible degradation, while lithium can produce permanent irreversible degradation. The degradation becomes worse as lithium content increases in the glass. Absorption spectra show this is due to partial oxidation of bismuth near-infrared emission center. Surprisingly, we notice the emission of bismuth exhibits blueshift, rather than redshift at a higher temperature, and the blueshift can be suppressed by increasing the lithium content.

  5. Light-Induced Surface Reactions at the Bismuth Vanadate/Potassium Phosphate Interface.

    Science.gov (United States)

    Favaro, Marco; Abdi, Fatwa F; Lamers, Marlene; Crumlin, Ethan J; Liu, Zhi; van de Krol, Roel; Starr, David E

    2017-09-18

    Bismuth vanadate has recently drawn significant research attention as a light-absorbing photoanode due to its performance for photoelectrochemical water splitting. In this study, we use in situ ambient pressure X-ray photoelectron spectroscopy with "tender" X-rays (4.0 keV) to investigate a polycrystalline bismuth vanadate (BiVO4) electrode in contact with an aqueous potassium phosphate (KPi) solution at open circuit potential under both dark and light conditions. This is facilitated by the creation of a 25 to 30 nm thick electrolyte layer using the "dip-and-pull" method. We observe that under illumination bismuth phosphate forms on the BiVO4 surface leading to an increase of the surface negative charge. The bismuth phosphate layer may act to passivate surface states observed in photoelectrochemical measurements. The repulsive interaction between the negatively charged surface under illumination and the phosphate ions in solution causes a shift in the distribution of ions in the thin aqueous electrolyte film, which is observed as an increase in their photoelectron signals. Interestingly, we find that such changes at the BiVO4/KPi electrolyte interface are reversible upon returning to dark conditions. By measuring the oxygen 1s photoelectron peak intensities from the phosphate ions and liquid water as a function of time under dark and light conditions, we determine the time scales for the forward and reverse reactions. Our results provide direct evidence for light-induced chemical modification of the BiVO4/KPi electrolyte interface.

  6. Conductance measurements on bismuth nanobridges

    Energy Technology Data Exchange (ETDEWEB)

    Pernau, H.F.; Schirm, C.; Scheer, E. [Univ. of Konstanz (Germany) Dept. of Physics

    2007-07-01

    By electron beam lithography and reactive ion etching we fabricate freestanding metallic bismuth nano-bridges which serve as starting point for arranging atomic-size and tunnel contacts with the help of the mechanically controlled breakjunction technique. Since the bridges are broken in cryogenic vacuum, the contacts are free of oxygen or other contamination. The transport measurements are performed in a {sup 3}He cryostat in the temperature range from 0.25 K up to 2 K and in transverse magnetic fields up to 8 T. After determining the preferred conductance values by recording conductance histograms, we study the conductance as a function of temperature, bias voltage and magnetic field at various contact values corresponding to those preferred conductance values. We observe reproducible conductance fluctuations as a function of both bias voltage and magnetic field and a well pronounced zero-bias anomaly which is modulated periodically with the magnetic field. We interprete our data in terms of phase coherent transport and onsetting superconductivity due to the granular structure of the film. (orig.)

  7. Stainless steel protection by in-situ oxide layer formation in stagnant lead-bismuth eutectic

    Energy Technology Data Exchange (ETDEWEB)

    Soler, L. [CIEMAT, Edificio 30, Dpto. Fision Nuclear, Avda. Complutense 22, 28040 Madrid, (Spain); Martin, F.J.; Hernandez, F.; Gomez-Briceno, D. [CIEMAT, Nuclear Fission Department, Structural Materials Project, Avda. Complutense 22, Building 30, 28040 Madrid (Spain)

    2004-07-01

    Accelerator Driven Systems (ADS) are designed to transmute long life and high activity nuclear wastes. The physico-chemical and nuclear characteristics of lead bismuth eutectic make this heavy liquid metal suitable to be used as spallation target and as coolant in ADS. However, heavy liquid metals, and particularly lead-bismuth eutectic, present a high aggressiveness to most of the structural materials. Nickel, chromium and iron, as constitutive elements of stainless steels, show a high solubility in lead-bismuth eutectic, that prevents their use as structural materials without any protection at temperatures higher than 400 deg. C for austenitic stainless steels and higher than 450 deg. C for martensitic steels. According to the available experience, proceeding from the former USSR, one of the possible ways to improve the performance of structural materials in Pb-Bi is the formation and maintenance of a protective oxide layer, which would constitute a barrier between the liquid metal and the steel. The corrosion resistance is determined by the oxygen thermodynamic activity in the liquid metal. For oxygen concentrations in the liquid metal below the equilibrium concentration for the formation of protective layers, the structural steels will suffer dissolution attack. On the contrary, if the oxygen concentration is higher than the necessary for the formation of oxide layers, the steels will experience an oxidation process, but very high concentrations provoke lead-bismuth oxides. Therefore, the oxygen content should be between these two limits in order to be able to form a protective oxide on the steel surface. The necessary oxygen content in the liquid metal may be obtained by gas injection, lead oxide interacting with the melt or the H{sub 2}/H{sub 2}O system. In this work, materials protection by 'in situ' oxidation has been studied in stagnant lead-bismuth, with different oxygen levels (H{sub 2}/H{sub 2}O ratios of 0.3, 0.03 and 0.003), at temperatures

  8. Photobleaching effect in bismuth-doped germanosilicate fibers.

    Science.gov (United States)

    Firstov, Sergei; Alyshev, Sergey; Khopin, Vladimir; Melkumov, Mikhail; Guryanov, Alexey; Dianov, Evgeny

    2015-07-27

    Photoinduced reduction of absorption (photobleaching) in bismuth-doped germanosilicate fibers irradiated with 532-nm laser has been observed for the first time. It was demonstrated that bismuth-related active centers having the absorption bands at wavelengths of 1400 and 1700 nm degrade under photoexcitation at 532 nm. The photobleaching process rate was estimated using conventional stretched exponential technique. It was found that the photobleaching rate in bismuth-doped germanosilicate fibers does not depend on type of bismuth-related active center. The possible underlying mechanism of photobleaching process in bismuth-doped fibers is discussed.

  9. Fabrication and characterization of grain-oriented bismuth vanadate ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Shantha, K.; Varma, K.B.R. [Indian Inst. of Science, Bangalore (India). Materials Research Centre

    1997-11-01

    Grain-oriented (GO; 79%), high density (96% of the theoretical value) ceramics of bismuth vanadate, Bi{sub 2}VO{sub 5.5}, have been fabricated via a liquid-phase-aided two-stage sintering process. Scanning electron microscopy (SEM) was employed to monitor the crystallite size and the morphology of the starting powders and the microstructure of the sintered ceramics. X-ray diffraction (XRD) studies were carried out to verify the grain-orientation in the ceramics. The dielectric constant and the conductivity studies carried out along the directions perpendicular and parallel to the pressing axis show significant anisotropies (1.7 and 5.3, respectively, at 300 K). The grain-oriented ceramics were found to exhibit improved ferroelectric properties, with higher remnant polarization (P{sub r}) and lower coercive field (E{sub c}) than those of the randomly oriented (RO) ceramics.

  10. Burnout current density of bismuth nanowires

    Science.gov (United States)

    Cornelius, T. W.; Picht, O.; Müller, S.; Neumann, R.; Völklein, F.; Karim, S.; Duan, J. L.

    2008-05-01

    Single bismuth nanowires with diameters ranging from 100nmto1μm were electrochemically deposited in ion track-etched single-pore polycarbonate membranes. The maximum current density the wires are able to carry was investigated by ramping up the current until failure occurred. It increases by three to four orders of magnitude for nanowires embedded in the template compared to bulk bismuth and rises with diminishing diameter. Simulations show that the wires are heated up electrically to the melting temperature. Since the surface-to-volume ratio rises with diminishing diameter, thinner wires dissipate the heat more efficiently to the surrounding polymer matrix and, thus, can tolerate larger current densities.

  11. Hyperfine splitting in lithium-like bismuth

    Energy Technology Data Exchange (ETDEWEB)

    Lochmann, Matthias; Froemmgen, Nadja; Hammen, Michael; Will, Elisa [Universitaet Mainz (Germany); Andelkovic, Zoran; Kuehl, Thomas; Litvinov, Yuri; Winters, Danyal; Sanchez, Rodolfo [GSI Helmholtzzentrum, Darmstadt (Germany); Botermann, Benjamin; Noertershaeuser, Wilfried [Technische Universitaet Darmstadt (Germany); Bussmann, Michael [Helmholtzzentrum Dresden-Rossendorf (Germany); Dax, Andreas [CERN, Genf (Switzerland); Hannen, Volker; Joehren, Raphael; Vollbrecht, Jonas; Weinheimer, Christian [Universitaet Muenster (Germany); Geppert, Christopher [Universitaet Mainz (Germany); GSI Helmholtzzentrum, Darmstadt (Germany); Stoehlker, Thomas [GSI Helmholtzzentrum, Darmstadt (Germany); Universitaet Heidelberg (Germany); Thompson, Richard [Imperial College, London (United Kingdom); Volotka, Andrey [Technische Universitaet Dresden (Germany); Wen, Weiqiang [IMP Lanzhou (China)

    2013-07-01

    High-precision measurements of the hyperfine splitting values on Li- and H-like bismuth ions, combined with precise atomic structure calculations allow us to test QED-effects in the regime of the strongest magnetic fields that are available in the laboratory. Performing laser spectroscopy at the experimental storage ring (ESR) at GSI Darmstadt, we have now succeeded in measuring the hyperfine splitting in Li-like bismuth. Probing this transition has not been easy because of its extremely low fluorescence rate. Details about this challenging experiment will be given and the achieved experimental accuracy are presented.

  12. Bismuth titanate nanorods and their visible light photocatalytic properties

    Energy Technology Data Exchange (ETDEWEB)

    Pei, L.Z., E-mail: lzpei@ahut.edu.cn; Liu, H.D.; Lin, N.; Yu, H.Y.

    2015-02-15

    Highlights: • Bismuth titanate nanorods have been synthesized by a simple hydrothermal process. • The size of bismuth titanate nanorods can be controlled by growth conditions. • Bismuth titanate nanorods show good photocatalytic activities of methylene blue and Rhodamine B. - Abstract: Bismuth titanate nanorods have been prepared using a facile hydrothermal process without additives. The bismuth titanate products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution TEM (HRTEM) and UV-vis diffusion reflectance spectrum. XRD pattern shows that the bismuth titanate nanorods are composed of cubic Bi{sub 2}Ti{sub 2}O{sub 7} phase. Electron microscopy images show that the length and diameter of the bismuth titanate nanorods are 50-200 nm and 2 μm, respectively. Hydrothermal temperature and reaction time play important roles on the formation and size of the bismuth titanate nanorods. UV-vis diffusion reflectance spectrum indicates that bismuth titanate nanorods have a band gap of 2.58 eV. The bismuth titanate nanorods exhibit good photocatalytic activities in the photocatalytic degradation of methylene blue (MB) and Rhodamine B (RB) under visible light irradiation. The bismuth titanate nanorods with cubic Bi{sub 2}Ti{sub 2}O{sub 7} phase are a promising candidate as a visible light photocatalyst.

  13. Characterization of the activity of ultrasound emitted in a perpendicular liquid flow using Particle Image Velocimetry (PIV) and electrochemical mass transfer measurements.

    Science.gov (United States)

    Barthès, Magali; Mazue, Gerald; Bonnet, Dimitri; Viennet, Remy; Hihn, Jean-Yves; Bailly, Yannick

    2015-05-01

    The present work is dedicated to the study of the interactions between a liquid circulation and a perpendicular acoustic wave propagation. A specific experimental setup was designed to study one transducer operating at 20 kHz, with the help of electrochemical mass transfer measurements combined with Particle Image Velocimetry (PIV) determination. Electrodes were located on the wall opposite to the acoustic emission. Experiments were performed for various Reynolds numbers: from 0 to 21700 (different liquid flow rates and viscosities). Both PIV and electrochemical measurements methods were found to be relevant, and had delivered complementary information. Even if PIV showed that the plume due to streaming was highly deflected by the additional flow, electrochemical measurements showed that there was still an activity, higher than in silent conditions, on the wall facing the transducer. Thus the ultrasound contribution remained noticeable on the surface opposite to the transducer even for a disturbed hydrodynamic environment due to the presence of a liquid circulation perpendicular to the wave propagation.

  14. Probing bismuth ferrite nanoparticles by hard x-ray photoemission: Anomalous occurrence of metallic bismuth

    Energy Technology Data Exchange (ETDEWEB)

    Chaturvedi, Smita; Rajendra, Ranguwar; Ballav, Nirmalya; Kulkarni, Sulabha, E-mail: s.kulkarni@iiserpune.ac.in [Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pune 411008 (India); Sarkar, Indranil [DESY Photon Science, Deutsches Elektronen-Synchrotron, 22607 Hamburg (Germany); Shirolkar, Mandar M. [Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026 (China); Jeng, U-Ser; Yeh, Yi-Qi [National Synchrotron Radiation Research Center, 101, Hsin-Ann Road, Science Park, Hsinchu 3007-6, Taiwan (China)

    2014-09-08

    We have investigated bismuth ferrite nanoparticles (∼75 nm and ∼155 nm) synthesized by a chemical method, using soft X-ray (1253.6 eV) and hard X-ray (3500, 5500, and 7500 eV) photoelectron spectroscopy. This provided an evidence for the variation of chemical state of bismuth in crystalline, phase pure nanoparticles. X-ray photoelectron spectroscopy analysis using Mg Kα (1253.6 eV) source showed that iron and bismuth were present in both Fe{sup 3+} and Bi{sup 3+} valence states as expected for bismuth ferrite. However, hard X-ray photoelectron spectroscopy analysis of the bismuth ferrite nanoparticles using variable photon energies unexpectedly showed the presence of Bi{sup 0} valence state below the surface region, indicating that bismuth ferrite nanoparticles are chemically inhomogeneous in the radial direction. Consistently, small-angle X-ray scattering reveals a core-shell structure for these radial inhomogeneous nanoparticles.

  15. Bismuth phosphates as intermediate temperature proton conductors

    DEFF Research Database (Denmark)

    Huang, Yunjie; Christensen, Erik; Shuai, Qin

    2017-01-01

    Proton conducting electrolyte materials operational in the intermediate temperature range of 200-400 °C are of special interest for applications in fuel cells and water electrolysers. Bismuth phosphates in forms of polycrystalline powders and amorphous glasses are synthesized and investigated...

  16. Effect of Lipophilic Bismuth Nanoparticles on Erythrocytes

    Directory of Open Access Journals (Sweden)

    Rene Hernandez-Delgadillo

    2015-01-01

    Full Text Available Lipophilic bismuth dimercaptopropanol nanoparticles (BisBAL NPs have a very important antimicrobial activity; however their effect on human cells or tissues has not been completely studied. Undesirable effects of bismuth include anemia which could result from suicidal erythrocyte death or eryptosis. The objective of this research was to determine the effect of bismuth dimercaptopropanol nanoparticles on blood cells. The nanoparticles are composed of 53 nm crystallites on average and have a spherical structure, agglomerating into clusters of small nanoparticles. Based on cell viability assays and optical microscopy, cytotoxicity on erythrocytes was observed after growing with 500 and 1000 µM of BisBAL NPs for 24 h. AM Calcein was retained inside erythrocytes when they were exposed to 100 µM (or lower concentrations of BisBAL NPs for 24 h, suggesting the absence of damage in plasmatic membrane. Genotoxic assays revealed no damage to genomic DNA of blood cells after 24 h of exposition to BisBAL NPs. Finally, 100–1000 µM of bismuth nanoparticles promotes apoptosis between blood cells after 24 h of incubation. Hence BisBAL NPs at concentrations lower than 100 µM do not cause damage on blood cells; they could potentially be used by humans without affecting erythrocytes and leukocytes.

  17. Development and Investigation of Bismuth Nanowires

    Science.gov (United States)

    2008-06-05

    To: technicalreports@afosr.af.mil Subject: Final Statement to Dr. Donald Silversmith Contract/Grant Title: Development and Investigation of...Report Development and Investigation of Bismuth Nanowires – Start up phase FA9550-07-1-0472 To Dr. Donald Silversmith AFOSR PI: Jimmy Xu

  18. An in situ scanning tunneling microscopic study of electrodeposition of bismuth on Au(1 1 1) in a 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid: Precursor adsorption and underpotential deposition

    Energy Technology Data Exchange (ETDEWEB)

    Fu Yongchun; Su Yuzhuan; Zhang Haiming; Yan Jiawei; Xie Zhaoxiong [State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China); Mao Bingwei, E-mail: bwmao@xmu.edu.c [State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005 (China)

    2010-11-30

    In this article, the electrodeposition of Bi on Au(1 1 1) surface in the underpotential region in BMIBF{sub 4} ionic liquid containing BiCl{sub 3} is studied by cyclic voltammetry and in situ scanning tunneling microscopy (STM). The cyclic voltammogram shows several cathodic and anodic peaks associated with underpotential deposition (UPD) of Bi and dissolution of the UPD deposit, respectively, in the potential region between -0.38 and -0.7 V versus Pt quasi-reference electrode. In situ STM results indicate there is a BiCl{sub 3} precursor adsorption stage prior to the Bi UPD. The adsorption of BiCl{sub 3} leads to the formation of unique hexagonal and trigonal supramolecular assembly with a Au(1 1 1)(10 x 10) structure. The initial stage of Bi UPD proceeds with the formation of Au(1 1 1)(7 x 7) R21.8{sup o} adlayer structure composed of Bi trigonal clusters at -0.5 V. A structural transformation occurred at -0.6 V resulting in a unique 'zipper-like' double-chain pattern composed of well-aligned Bi trigonal clusters which can be denoted by Au(1 1 1)(5 x 25{radical}3/3) structural model. The trigonal clusters composed of six Bi atoms seem to be the main characteristic elemental units of Bi UPD adlayer regardless of underpotential shift. These features are dramatically different from those observed in Bi(III)-containing acidic aqueous solutions as well as in chloroaluminated ionic liquid, but are similar to those of Sb UPD in BMIBF{sub 4} ionic liquid, which reveals profound solvent effects on the electrodeposition of semimetals.

  19. Using polycrystalline bismuth filter in an ultracold neutron source with superfluid helium

    Science.gov (United States)

    Serebrov, A. P.; Lyamkin, V. A.; Runov, V. V.; Ivanov, S. A.; Onegin, M. S.; Fomin, A. K.

    2015-10-01

    Placing polycrystalline bismuth filter in front of an ultracold neutron (UCN) source with superfluid helium at 1 K is shown to be effective. The use of this filter ensures a 30-fold decrease (down to 0.5 W) in the level of heat load in the UCN source, while reducing by 30% the flux of neutrons with 9-Å wavelength (which are converted into UCNs). The phenomenon of small-angle scattering on polycrystalline bismuth has been studied and shown to be insignificant. Cooling of the filter to liquid nitrogen temperature increases the transmission of 9-Å neutrons by only 8%; hence, creation of this cooling system is inexpedient. A project of a technological complex designed for the UCN source at the PIK reactor is presented, which ensures the removal of 1-W heat load from the UCN source with superfluid helium at a 1-K temperature level.

  20. Bismuth( Ⅲ ) Salts: Green Catalysts for Organic Transformations

    Institute of Scientific and Technical Information of China (English)

    C. Le Roux

    2005-01-01

    @@ 1Introduction Bismuth, the heaviest stable element in the periodic table, stands out from other heavy elements (such as mercury, thallium and lead) due to its relatively non-toxic character which confers on bismuth the enviable status of being an eco-friendly element. Therefore, bismuth and its compounds hold considerable promise as useful catalysts for green chemistry. The research presented in this communication is devoted to the applications of bismuth( Ⅲ ) salts as catalysts for organic transformations.After some general comments about bismuth and a short presentation of the various applications of bismuth( Ⅲ ) salts in organic synthesis, this communication will focus on the works done in our research group during the last several years which deals mainly with electrophilic substitutions. When appropriate, some mechanistic details will be given.

  1. Picosecond 1.3{-}\\unicode{956} {\\text{m}} bismuth fibre laser mode-locked by a nonlinear loop mirror

    Science.gov (United States)

    Khegai, A. M.; Afanas'ev, F. V.; Riumkin, K. E.; Firstov, S. V.; Khopin, V. F.; Myasnikov, D. V.; Mel'kumov, M. A.; Dianov, E. M.

    2016-12-01

    The influence of the concentration of bismuth active centres (BACs) in phosphosilicate fibres on their optical parameters, including gain coefficient and non-saturable losses, has been studied. A range of BAC concentrations optimal for designing ultrashort-pulse (USP) lasers was chosen based on the obtained results. The optimised fibre was used to fabricate an all-fibre 1.3-\\unicode{956}{\\text{m}} USP laser mode-locked by a nonlinear loop mirror, which emits 11.3-{\\text{ps}} pulses with an energy of 1.65 {\\text{nJ}} and a repetition rate of 3.6 {\\text{MHz}}. A bismuth fibre amplifier made it possible to increase the pulse energy to 8.3 {\\text{nJ}}. After compression in a diffraction grating compressor, the pulse duration decreased to 530 {\\text{fs}}.

  2. Electrical resistivity of thin bismuth films

    Science.gov (United States)

    Kumar, A.; Katyal, O. P.

    1990-05-01

    The effect of the film thickness of a bismuth film deposited on glass substrate on its electrical resistivity was investigated for films from 41 to 225 nm thickness, in the temperature range 77-350 K. Results show that the electrical resistivity decreases with increasing temperature and that, for films 98.3 and 225.9 nm thick there exists a minimum (between 260 and 350 K) in resistivity at some temperature, Tc. This minimum shifts toward higher temperature for thinner samples, and lies above 350 K. The thickness dependence of the bismuth film resistivity, obtained at 77, 150, and 300 K, can be explained by a modified Fuchs model, which takes into account the thickness dependence of carrier density.

  3. Flame spray synthesis under a non-oxidizing atmosphere: Preparation of metallic bismuth nanoparticles and nanocrystalline bulk bismuth metal

    Energy Technology Data Exchange (ETDEWEB)

    Grass, Robert N.; Stark, Wendelin J. [Institute for Chemical and Bioengineering, ETH Zuerich (Switzerland)], E-mail: wendelin.stark@chem.ethz.ch

    2006-10-15

    Metallic bismuth nanoparticles of over 98% purity were prepared by a modified flame spray synthesis method in an inert atmosphere by oxygen-deficient combustion of a bismuth-carboxylate based precursor. The samples were characterized by X-ray diffraction, thermal analysis and scanning electron microscopy confirming the formation of pure, crystalline metallic bismuth nanoparticles. Compression of the as-prepared powder resulted in highly dense, nanocrystalline pills with strong electrical conductivity and bright metallic gloss.

  4. Pharmacokinetics and bioequivalence of ranitidine and bismuth derived from two compound preparations

    Institute of Scientific and Technical Information of China (English)

    Quan Zhou; Zou-Rong Ruan; Hong Yuan; Bo Jiang; Dong-Hang Xu

    2006-01-01

    AIM: To evaluate the bioequivalence of ranitidine and bismuth derived from two compound preparations.METHODS: The bioavailability was measured in 20healthy male Chinese volunteers following a single oral dose (equivalent to 200 mg of ranitidine and 220 mg of bismuth) of the test or reference products in the fasting state. Then blood samples were collected for 24 h.Plasma concentrations of ranitidine and bismuth were analyzed by high-performance liquid chromatography and inductively coupled plasma-mass spectrometry (ICPMS), respectively. The non-compartmental method was used for pharmacokinetic analysis. Log-transformed Cmax,AUC(0-t) and AUC(0-∞) were tested for bioequivalence using ANOVA and Schuirmann two-one sided t-test. Tmax was analyzed by Wilcoxon's test.RESULTS: Various pharmacokinetic parameters of ranitidine derived from the two compound preparations,including Cmax, AUC(0-t), AUC(0-∞), Tmax and T1/2, were nearly consistent with previous observations. These parameters derived from test and reference drug were as follows: Cmax(0.67 ± 0.21 vs 0.68 ± 0.22mg/L), AUC(0-t)(3.1 ± 0.6 vs 3.0 ± 0.7 mg/L per hour),AUC(0-∞)(3.3 ± 0.6 vs 3.2 ± 0.8 mg/L per hour),Tmax (2.3 ± 0.9 vs 2.1 ± 0.9 h) and T1/2 (2.8 ± 0.3 vs 3.1± 0.4 h). In addition, double-peak absorption profiles of ranitidine were found in some Chinese volunteers.For bismuth, those parameters derived from test and reference drug were as follows: Cmax (11.80 ± 7.36 vs 11.40 ± 6.55 μg/L),AUC(0-t) (46.65 ± 16.97 vs 47.03 ±21.49 μg/L per hour), Tmax (0.50 ± 0.20 vs 0.50 ± 0.20 h)and T1/2 (10.2 ± 2.3 vs 13.0 ± 6.9 h). Ninety percent of confidence intervals for the test/reference ratio of Cmax,AUC(0-t) and AUC(0-∞) derived from both ranitidine and bismuth were found within the bioequivalence acceptable range of 80%-125%. No significant difference was found in Tmax derived from both ranitidine and bismuth.CONCLUSION: The two compound preparations are bioequivalent and may be prescribed

  5. Factors affecting bismuth vanadate photoelectrochemical performance

    OpenAIRE

    Sinclair, Timothy S.; Hunter, Bryan M.; Winkler, Jay R.; Gray, Harry B.; Müller, Astrid M.

    2015-01-01

    Bismuth vanadate is a promising photoanode material, but recent reports on undoped BiVO_4 without sublayers and co-catalysts showed large variations in photocurrent generation. We addressed this issue by correlating photoelectrochemical performance with physical properties. We devised a novel anodic electrodeposition procedure with iodide added to the aqueous plating bath, which allowed us to prepare BiVO_4 photoanodes with virtually identical thicknesses but different morphologies, and we co...

  6. Electrocatalytic activity of bismuth doped silver electrodes

    CERN Document Server

    Amjad, M

    2002-01-01

    Investigation of redox reactions on silver, and bismuth doped silver electrodes in aqueous KOH solutions, by using potentiostatic steady-state polarization technique, has been carried out. The redox wave potential and current displacements along with multiplicity of the latter have been examined. These electrodes were employed for the oxidation of organic molecules such as ethylamine in alkaline media. Subsequently, these electrodes were ranked with respect to their activity for the redox reactions. (author)

  7. Polonium evaporation from dilute liquid metal solutions

    CERN Document Server

    Rizzi, Matthias; Eichler, Robert; Türler, Andreas; Mendonça, Tania Melo; Stora, Thierry; Gonzalez Prieto, Borja; Aerts, Alexander; Schumann, Dorothea

    2014-01-01

    The evaporation behavior of polonium as one of the most hazardous radionuclides produced in spallation based neutron sources with liquid lead-bismuth targets has been quantified in this study. The normalized apparent vapor pressure, i.e. the Henry constant of polonium over liquid lead-bismuth eutectic was determined in the temperature range relevant for operation of such targets, i.e. 164-500 degrees C. For comparison and better fundamental understanding, the Henry constant of polonium over pure liquid bismuth was determined in a temperature range of 300-500 degrees C. The Henry constants of polonium in this temperature range were found to be orders of magnitude higher than expected from earlier studies at higher temperatures. Possible mechanisms responsible for this unexpected behavior are discussed.

  8. Efficient enhancement of bismuth NIR luminescence by aluminum and its mechanism in bismuth doped germanate laser glass

    DEFF Research Database (Denmark)

    Wang, L.P.; Tan, L.L.; Yue, Yuanzheng

    2016-01-01

    on how to improve the luminescence efficiency. Here, we demonstrate that addition of aluminum can enhance the bismuth near-infrared luminescence by more than 10 000 times, which is right followed by the discussion on the mechanism on why this can happen. We believe this work can be helpful for designing...... bismuth-doped multiple component laser glasses with high efficiency. In addition, because of high susceptibility of bismuth to local field change, it can be used as probe ion to envision glass structures. Using bismuth as a luminescent structural probe, we can see the modifier ions of Bi...

  9. The fabrication and thermal properties of bismuth-aluminum oxide nanothermometers

    Science.gov (United States)

    Wang, Chiu-Yen; Chen, Shih-Hsun; Tsai, Ping-Hsin; Chiou, Chung-Han; Hsieh, Sheng-Jen

    2017-01-01

    Bismuth (Bi) nanowires, well controlled in length and diameter, were prepared by using an anodic aluminum oxide (AAO) template-assisted molding injection process with a high cooling rate. A high performance atomic layer deposition (ALD)-capped bismuth-aluminum oxide (Bi-Al2O3) nanothermometer is demonstrated that was fabricated via a facile, low-cost and low-temperature method, including AAO templated-assisted molding injection and low-temperature ALD-capped processes. The thermal behaviors of Bi nanowires and Bi-Al2O3 nanocables were studied by in situ heating transmission electron microscopy. Linear thermal expansion of liquid Bi within native bismuth oxide nanotubes and ALD-capped Bi-Al2O3 nanocables were evaluated from 275 °C to 700 °C and 300 °C to 1000 °C, respectively. The results showed that the ALD-capped Bi-Al2O3 nanocable possesses the highest working temperature, 1000 °C, and the broadest operation window, 300 °C-1000 °C, of a thermal-expanding type nanothermometer. Our innovative approach provides another way of fabricating core-shell nanocables and to further achieve sensing local temperature under an extreme high vacuum environment.

  10. Heat-Pipe Bismuth Laser; Examination of Laser Action at 4722A in Bismuth Vapor

    Science.gov (United States)

    1976-11-01

    transitions in other atomic vapors. 13. MODELING OF THE INITIAL BREAKDOWN PROCESS During the initial nanosecond after the fast thyratron switch closes suddenly...lasers computer modeling , laser kin etics bismuth vapor pressure and composition excitation cross sections bismuth dim ers e8ifn.eividienibbek 2Q...P3 / 2 " p $3/4 transi- 3/4 3/2 tion probability is at least a factor of 20 too low. Continuation of the computer modeling begun in this study could

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

    Science.gov (United States)

    Sahin, Cuneyt

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

  12. NIR photoluminescence of bismuth-doped CsCdBr{sub 3} – The first ternary bromide phase with a univalent bismuth impurity center

    Energy Technology Data Exchange (ETDEWEB)

    Romanov, Alexey N., E-mail: alexey.romanov@list.ru [N.N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 4 Kosygina Street, 119991 (Russian Federation); Veber, Alexander A. [Universität Erlangen-Nürnberg, Lehrstuhl für Glas und Keramik, Martensstraße 5, 91058 Erlangen (Germany); Vtyurina, Daria N. [N.N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 4 Kosygina Street, 119991 (Russian Federation); Kouznetsov, Mikhail S.; Zaramenskikh, Ksenia S.; Lisitsky, Igor S. [State Scientific-Research and Design Institute of Rare-Metal Industry “Giredmet” JSC, 5-1 B.Tolmachevsky Lane, 119017 Moscow (Russian Federation); Fattakhova, Zukhra T.; Haula, Elena V. [N.N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 4 Kosygina Street, 119991 (Russian Federation); Loiko, Pavel A.; Yumashev, Konstantin V. [Center for Optical Materials and Technologies, Belarusian National Technical University, 65/17 Nezavisimosti Avenue, 220013 Minsk (Belarus); Korchak, Vladimir N. [N.N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 4 Kosygina Street, 119991 (Russian Federation)

    2015-11-15

    Single crystals of ternary bromide phase CsCdBr{sub 3} doped with univalent bismuth cations are prepared for the first time by the Bridgman method. Bi{sup +} impurity center emits a broadband long-lived near-infrared photoluminescence with a maximum at ~1053 nm. The characteristics of this photoluminescence and its relations with the energy spectrum of Bi{sup +} impurity center are discussed. A comparison of Bi{sup +} photoluminescence in CsCdBr{sub 3} and ternary chlorides (studied previously) is performed. - Highlights: • Single crystals of Bi{sup +}-doped ternary bromide CsCdBr{sub 3} were prepared. • Broadband NIR photoluminescence was observed from Bi{sup +}-doped CsCdBr{sub 3}. • Single optical center is responsible for NIR emission in Bi{sup +}-doped CsCdBr{sub 3}.

  13. Structural relaxation in bismuth and lead borate glasses

    Science.gov (United States)

    Bajaj, Anu; Khanna, Atul

    2012-06-01

    Bismuth and lead borate glasses were prepared by melt quench technique. Effects of heat treatment on the density and thermal properties of bismuth and lead borate glasses was studied by annealing the glasses at 350°C for 500 h. Density of all bismuth borate glasses increases by about 0.5-0.7% with annealing and the effect is more in glasses with higher Bi2O3 concentration. In bismuth borate glasses with 50 and 55 mol % Bi2O3 we found an extraordinary large increase of Tg by 15°C after thermal annealing. All bismuth borate glasses remained completely clear and transparent on annealing. Lead borate glasses become cloudy on thermal annealing indicating occurrence of phase separation in these glasses.

  14. Vibration Monitoring Using Fiber Optic Sensors in a Lead-Bismuth Eutectic Cooled Nuclear Fuel Assembly

    OpenAIRE

    Ben De Pauw; Alfredo Lamberti; Julien Ertveldt; Ali Rezayat; Katrien van Tichelen; Steve Vanlanduit; Francis Berghmans

    2016-01-01

    Excessive fuel assembly vibrations in nuclear reactor cores should be avoided in order not to compromise the lifetime of the assembly and in order to prevent the occurrence of safety hazards. This issue is particularly relevant to new reactor designs that use liquid metal coolants, such as, for example, a molten lead-bismuth eutectic. The flow of molten heavy metal around and through the fuel assembly may cause the latter to vibrate and hence suffer degradation as a result of, for example, fr...

  15. Experimental evidence of the existence of a nonstationary coherent crystal state in bismuth

    Science.gov (United States)

    Misochko, O. V.

    2014-02-01

    The excitation of a bismuth (Bi) crystal by intense ultrashort laser pulses at liquid-helium temperature leads to consistent motion of atoms and variations in the electron density. At various time instants over an interval reaching several dosen picoseconds, atoms in the Bi lattice exhibit sequential pairing in the real and reciprocal spaces. This behavior may correspond to the formation of a coherent crystal—a special state of matter that combines the properties of a solid and quantum fluid. Experimental data showing evidence of the possible existence of this unusual state are presented and analyzed.

  16. Bismuth(III) dialkyldithiophosphates: Facile single source precursors for the preparation of bismuth sulfide nanorods and bismuth phosphate thin films

    Energy Technology Data Exchange (ETDEWEB)

    Biswal, Jasmine B. [Department of Chemistry, University of Mumbai, Vidyanagari, Santacruz (East), Mumbai 400098 (India); Garje, Shivram S., E-mail: ssgarje@chem.mu.ac.in [Department of Chemistry, University of Mumbai, Vidyanagari, Santacruz (East), Mumbai 400098 (India); Nuwad, Jitendra; Pillai, C.G.S. [Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

    2013-08-15

    Two different phase pure materials (Bi{sub 2}S{sub 3} and Bi{sub 2}P{sub 4}O{sub 13}) have been prepared under different conditions using the same single source precursors. Solvothermal decomposition of the complexes, Bi(S{sub 2}P(OR){sub 2}){sub 3} [where, R=Methyl (Me) (1), Ethyl (Et) (2), n-Propyl (Pr{sup n}) (3) and iso-Propyl (Pr{sup i}) (4)] in ethylene glycol gave orthorhombic bismuth sulfide nanorods, whereas aerosol assisted chemical vapor deposition (AACVD) of the same precursors deposited monoclinic bismuth tetraphosphate (Bi{sub 2}P{sub 4}O{sub 13}) thin films on glass substrates. Surface study of the thin films using SEM illustrated the formation of variety of nanoscale morphologies (spherical-, wire-, pendent-, doughnut- and flower-like) at different temperatures. AFM studies were carried out to evaluate quality of the films in terms of uniformity and roughness. Thin films of average roughness as low as 1.4 nm were deposited using these precursors. Photoluminescence studies of Bi{sub 2}P{sub 4}O{sub 13} thin films were also carried out. - Graphical abstract: Solvothermal decomposition of bismuth(III) dialkyldithiophosphates in ethylene glycol gave Bi{sub 2}S{sub 3} nanoparticles, whereas aerosol assisted chemical vapor deposition of these single source precursors deposited Bi{sub 2}P{sub 4}O{sub 13} thin films. Display Omitted - Highlights: • Preparation of phase pure orthorhombic Bi{sub 2}S{sub 3} nanorods and monoclinic Bi{sub 2}P{sub 4}O{sub 13} thin films. • Use of single source precursors for deposition of bismuth phosphate thin films. • Use of solvothermal decomposition and AACVD methods. • Morphology controlled synthesis of Bi{sub 2}P{sub 4}O{sub 13} thin films. • Bi{sub 2}S{sub 3} nanorods and Bi{sub 2}P{sub 4}O{sub 13} thin films using same single source precursors.

  17. Preparation of Bismuth Subcarbonate by Ball-milling Coversion Method Using Bismuth Oxide%球磨转化法由氧化铋制取次碳酸铋研究

    Institute of Scientific and Technical Information of China (English)

    蒋叶; 唐朝波; 唐谟堂; 杨声海; 何静; 陈永明; 杨建广

    2013-01-01

      针对次碳酸铋传统制备工艺存在试剂消耗大、产生大量氨氮废水等问题,提出了一种用氧化铋和碳酸氢铵机械球磨直接制备次碳酸铋新工艺,考察了碳酸氢铵浓度、液固体积质量比、球料质量比、反应时间对氧化铋转化率的影响。结果表明,在碳酸氢铵浓度为2.5 mol/L、液固体积质量比为7∶1、球料质量比为8∶1、反应时间为2 h、室温条件下,氧化铋转化率达93.23%。该工艺流程简短,成本低,转化母液可循环利用,解决了传统工艺试剂消耗大及产生大量氨氮废水等问题。%A new process for preparation of bismuth subcarbonate by ball-milling coversion method using bismuth oxide has been proposed .T he effects of ammonium bicarbonate concentrate ,liquid/solid ratio ,mass ratio of ball to bismuth oxide and milling time on conversion rate of bismuth oxide were ex-amined .The results showed that the direct conversion rate of bismuth oxide colud reach 93 .23% under the optimum conditions which the ammonium bicarbonate concentration was 2 .5 mol/L ,liquid/solid ratio was 7∶1 ,mass ratio of ball to bismuth oxide was 8∶1 ,and milling 2 hours at room temperature . The process has the advantage of short procedure ,cheap reactant ,low cost ,and mother liquid can be u-tilized circularly .

  18. Bismuth-Based Quadruple Therapy with Bismuth Subcitrate, Metronidazole, Tetracycline and Omeprazole in the Eradication of Helicobacter pylori

    Directory of Open Access Journals (Sweden)

    Raymond Lahaie

    2001-01-01

    Full Text Available BACKGROUND: A previous study showed that 14 days of qid bismuth-based triple therapy with tetracycline 500 mg, metronidazole 250 mg and colloidal bismuth subcitrate 120 mg resulted in excellent Helicobacter pylori eradication rates (89.5%. The present study looked at a shorter treatment period by adding omeprazole and by reducing the dose of tetracycline.

  19. Optical Properties of Bismuth Tellurite Based Glass

    Directory of Open Access Journals (Sweden)

    Hooi Ming Oo

    2012-04-01

    Full Text Available A series of binary tellurite based glasses (Bi2O3x (TeO2100−x was prepared by melt quenching method. The density, molar volume and refractive index increase when bismuth ions Bi3+ increase, this is due to the increased polarization of the ions Bi3+ and the enhanced formation of non-bridging oxygen (NBO. The Fourier transform infrared spectroscopy (FTIR results show the bonding of the glass sample and the optical band gap, Eopt decreases while the refractive index increases when the ion Bi3+ content increases.

  20. Optical properties of bismuth tellurite based glass.

    Science.gov (United States)

    Oo, Hooi Ming; Mohamed-Kamari, Halimah; Wan-Yusoff, Wan Mohd Daud

    2012-01-01

    A series of binary tellurite based glasses (Bi(2)O(3))(x) (TeO(2))(100-) (x) was prepared by melt quenching method. The density, molar volume and refractive index increase when bismuth ions Bi(3+) increase, this is due to the increased polarization of the ions Bi(3+) and the enhanced formation of non-bridging oxygen (NBO). The Fourier transform infrared spectroscopy (FTIR) results show the bonding of the glass sample and the optical band gap, E(opt) decreases while the refractive index increases when the ion Bi(3+) content increases.

  1. Mesures de taux de production d'éléments gazeux et volatiles lors de réactions induites par des protons de 1 et 1,4 GeV sur des cibles épaisses de plomb-bismuth liquides

    CERN Document Server

    Tall, Yoro

    2008-01-01

    The integrated project EUROTRANS (European Research Programme for the Transmutation of High Level Nuclear Waste in an Accelerator Driven System) of the 6th Euratom Framework Programme aims to demonstrate the transmutation of radioactive waste in ADS (Accelerator Driven Sub-critical system). It will carry out a first advanced design of an experimental facility to demonstrate the technical feasibility of transmutation, and will produce a conceptual design of an industrial facility dedicated to transmutation. An ADS consists of three fundamental elements: the accelerator of protons, the sub-critical core and the spallation target which one molten lead-bismuth concept is studied by the SUBATECH (physique SUBAtomique et des TECHnologies associées) laboratory in Nantes. The irradiation of molten lead-bismuth target with energetic proton beam generates volatile and radioactive residues. In order to determine experimentally the production rates of gas and volatile elements following a spallation reaction in a lead-b...

  2. Modular Lead-Bismuth Fast Reactors in Nuclear Power

    Directory of Open Access Journals (Sweden)

    Vladimir Petrochenko

    2012-09-01

    Full Text Available On the basis of the unique experience of operating reactors with heavy liquid metal coolant–eutectic lead-bismuth alloy in nuclear submarines, the concept of modular small fast reactors SVBR-100 for civilian nuclear power has been developed and validated. The features of this innovative technology are as follows: a monoblock (integral design of the reactor with fast neutron spectrum, which can operate using different types of fuel in various fuel cycles including MOX fuel in a self-providing mode. The reactor is distinct in that it has a high level of self-protection and passive safety, it is factory manufactured and the assembled reactor can be transported by railway. Multipurpose application of the reactor is presumed, primarily, it can be used for regional power to produce electricity, heat and for water desalination. The Project is being realized within the framework of state-private partnership with joint venture OJSC “AKME-Engineering” established on a parity basis by the State Atomic Energy Corporation “Rosatom” and the Limited Liability Company “EuroSibEnergo”.

  3. On the use of bismuth as a neutron filter

    CERN Document Server

    Adib, M

    2003-01-01

    A formula is given which, for neutron energies in the range 10 sup - sup 4 bismuth temperature and crystalline form. Computer programs have been developed which allow calculations for the Bi rhombohedral structure in its poly-crystalline form and its equivalent hexagonal close-packed structure. The calculated total neutron cross-sections for poly-crystalline Bi at different temperatures were compared with the measured values. An overall agreement is indicated between the formula fits and experimental data. Agreement was also obtained for values of Bi-single crystals, at room and liquid nitrogen temperatures. A feasibility study for use of Bi in powdered form, as a cold neutron filter, is detailed in terms of the optimum Bi-single crystal thickness, mosaic spread, temperature and cutting plane for efficient transmission of thermal-reactor neutrons, and also for rejection of the accom...

  4. Compatibility tests of steels in flowing liquid lead-bismuth

    Energy Technology Data Exchange (ETDEWEB)

    Barbier, F.; Benamati, G. E-mail: benamati@brasimone.enea.it; Fazio, C.; Rusanov, A

    2001-06-01

    The behaviour of steels exposed to flowing Pb-55Bi was evaluated. The materials tested are the two austenitic steels AISI 316L and 1.4970, and the six martensitic steels Optifer IVc, T91, Batman 27, Batman 28, EP823 and EM10 which were exposed to flowing Pb-55Bi for 1000, 2000 and 3000 h and at two temperatures (573 and 743 K). The corrosion tests were conducted in the non-isothermal loop of IPPE-Obninsk under a controlled oxygen level (10{sup -6} wt%). The compatibility study showed that at a lower temperature, a very thin oxide layer (<1 {mu}m) was formed on the steels. At higher temperature, austenitic steels also exhibited a thin oxide layer sufficient to prevent their dissolution in the melt. A thicker oxide, which grew according to a parabolic law, was observed on the surface of the martensitic steels. The oxidation resistance behaviour of the martensitic steels was correlated with their alloying elements.

  5. Determining the background levels of bismuth in tissues of wild game birds: a first step in addressing the environmental consequences of using bismuth shotshells.

    Science.gov (United States)

    Jayasinghe, R; Tsuji, L J S; Gough, W A; Karagatzides, J D; Perera, D; Nieboer, E

    2004-11-01

    Bismuth shotshells have been approved as a "nontoxic" alternative to lead in North America. Approval was based on a limited number of studies; even background levels of bismuth in wildfowl were unknown. We report on the concentration of bismuth (and lead) in muscle and liver tissues of wildfowl (Anas platyrhynchos, Anas acuta, Anas crecca, Branta canadensis, Chen caerulescens) harvested with lead shotshell. Average liver-bismuth levels detected in the present study (e.g., teal, 0.05 microg/g dw; mallard, 0.09 microg/g dw) suggest analytical error in other studies examining the effects of bismuth in birds. Significant positive relationships between bismuth- and lead-tissue levels for muscle when all species were combined (and for B. canadensis and C. caerulescens separately) can be explained by noting that bismuth is a contaminant of lead. Thus, more research is recommended to confirm the appropriateness of bismuth as a "nontoxic" shot alternative.

  6. Design of alumina forming FeCrAl steels for lead or lead-bismuth cooled fast reactors

    Science.gov (United States)

    Lim, Jun; Hwang, Il Soon; Kim, Ji Hyun

    2013-10-01

    Iron-chromium-aluminum alloys containing 15-20 wt.% Cr and 4-6 wt.% Al have shown excellent corrosion resistance in the temperature range up to 600 °C or higher in liquid lead and lead-bismuth eutectic environments by the formation of protective Al2O3 layers. However, the higher Cr and Al concentrations in ferritic alloys could be problematic because of severe embrittlement in the manufacturing process as well as in service, caused by the formation of brittle phases. For this reason, efforts worldwide have so far mainly focused on the development of aluminizing surface treatments. However, aluminizing surface treatments have major disadvantages of cost, processing difficulties and reliability issues. In this study, a new FeCrAl alloy is proposed for structural materials in lead and lead-bismuth cooled nuclear applications. The alloy design relied on corrosion experiments in high temperature lead and lead-bismuth eutectic environments and computational thermodynamic calculations using the commercial software, JMatPro. The design of new alloys has focused on the optimization of Cr and Al levels for the formation of an external Al2O3 layer which can provide excellent oxidation and corrosion resistance in liquid lead alloys in the temperature range 300-600 °C while still retaining workable mechanical properties.

  7. Light-emitting Diodes

    Science.gov (United States)

    Opel, Daniel R.; Hagstrom, Erika; Pace, Aaron K.; Sisto, Krisanne; Hirano-Ali, Stefanie A.; Desai, Shraddha

    2015-01-01

    Background: In the early 1990s, the biological significance of light-emitting diodes was realized. Since this discovery, various light sources have been investigated for their cutaneous effects. Study design: A Medline search was performed on light-emitting diode lights and their therapeutic effects between 1996 and 2010. Additionally, an open-label, investigator-blinded study was performed using a yellow light-emitting diode device to treat acne, rosacea, photoaging, alopecia areata, and androgenetic alopecia. Results: The authors identified several case-based reports, small case series, and a few randomized controlled trials evaluating the use of four different wavelengths of light-emitting diodes. These devices were classified as red, blue, yellow, or infrared, and covered a wide range of clinical applications. The 21 patients the authors treated had mixed results regarding patient satisfaction and pre- and post-treatment evaluation of improvement in clinical appearance. Conclusion: Review of the literature revealed that differing wavelengths of light-emitting diode devices have many beneficial effects, including wound healing, acne treatment, sunburn prevention, phototherapy for facial rhytides, and skin rejuvenation. The authors’ clinical experience with a specific yellow light-emitting diode device was mixed, depending on the condition being treated, and was likely influenced by the device parameters. PMID:26155326

  8. Inhibition of urease by bismuth(III): implications for the mechanism of action of bismuth drugs.

    Science.gov (United States)

    Zhang, Li; Mulrooney, Scott B; Leung, Andy F K; Zeng, Yibo; Ko, Ben B C; Hausinger, Robert P; Sun, Hongzhe

    2006-10-01

    Bismuth compounds are widely used for the treatment of peptic ulcers and Helicobacter pylori infections. It has been suggested that enzyme inhibition plays an important role in the antibacterial activity of bismuth towards this bacterium. Urease, an enzyme that converts urea into ammonia and carbonic acid, is crucial for colonization of the acidic environment of the stomach by H. pylori. Here, we show that three bismuth complexes exhibit distinct mechanisms of urease inhibition, with some differences dependent on the source of the enzyme. Bi(EDTA) and Bi(Cys)(3) are competitive inhibitors of jack bean urease with K(i) values of 1.74 +/- 0.14 and 1.84 +/- 0.15 mM, while the anti-ulcer drug, ranitidine bismuth citrate (RBC) is a non-competitive inhibitor with a K (i) value of 1.17 +/- 0.09 mM. A (13)C NMR study showed that Bi(Cys)(3) reacts with jack bean urease during a 30 min incubation, releasing free cysteines from the metal complex. Upon incubation with Bi(EDTA) and RBC, the number of accessible cysteine residues in the homohexameric plant enzyme decreased by 5.80 +/- 0.17 and 11.94 +/- 0.13, respectively, after 3 h of reaction with dithiobis(2-nitrobenzoic acid). Kinetic analysis showed that Bi(EDTA) is both a competitive inhibitor and a time-dependent inactivator of the recombinant Klebsiella aerogenes urease. The active C319A mutant of the bacterial enzyme displays a significantly reduced sensitivity toward inactivation by Bi(EDTA) compared with the wild-type enzyme, consistent with binding of Bi(3+) to the active site cysteine (Cys(319)) as the mechanism of enzyme inactivation.

  9. Hierarchical bismuth phosphate microspheres with high photocatalytic performance

    Energy Technology Data Exchange (ETDEWEB)

    Pei, Lizhai; Wei, Tian; Lin, Nan; Yu, Haiyun [Anhui University of Technology, Ma' anshan (China). Key Laboratory of Materials Science and Processing of Anhui Province

    2016-05-15

    Hierarchical bismuth phosphate microspheres have been prepared by a simple hydrothermal process with polyvinyl pyrrolidone. Scanning electron microscopy observations show that the hierarchical bismuth phosphate microspheres consist of nanosheets with a thickness of about 30 nm. The diameter of the microspheres is about 1 - 3 μm. X-ray diffraction analysis shows that the microspheres are comprised of triclinic Bi{sub 23}P{sub 4}O{sub 44.5} phase. The formation of the hierarchical microspheres depends on polyvinyl pyrrolidone concentration, hydrothermal temperature and reaction time. Gentian violet acts as the pollutant model for investigating the photocatalytic activity of the hierarchical bismuth phosphate microspheres under ultraviolet-visible light irradiation. Irradiation time, dosage of the hierarchical microspheres and initial gentian violet concentration on the photocatalytic efficiency are also discussed. The hierarchical bismuth phosphate microspheres show good photocatalytic performance for gentian violet removal in aqueous solution.

  10. Diffused phase transition in fine-grained bismuth vanadate ceramics

    OpenAIRE

    Shantha, K; Varma, KBR

    1999-01-01

    Nanocrystalline powders of ferroelectric bismuth vanadate, Bi4V2O11 (n-BiV), with crystallite size less than 50 nm, were obtained by mechanical milling of a stoichiometric mixture of bismuth oxide and vanadium pentoxide. The n-BiV powders on sintering yielded high-density, fine-grained ceramics with improved dielectric and polar characteristics. Dielectric studies on samples obtained from milled powders indicated that the ferroelectric-to-paraelectric phase transition temperature is strongly ...

  11. Melting and solidification of bismuth inclusions in aluminium

    DEFF Research Database (Denmark)

    Thoft, N.B.; Bohr, J.; Buras, B.

    1995-01-01

    Supercooling of crystalline bismuth inclusions in aluminium crystals has been observed and studied with different techniques: x-ray diffraction, in situ Rutherford backscattering/channelling spectrometry and transmission electron microscopy. The results of the measurements with different experime......Supercooling of crystalline bismuth inclusions in aluminium crystals has been observed and studied with different techniques: x-ray diffraction, in situ Rutherford backscattering/channelling spectrometry and transmission electron microscopy. The results of the measurements with different...

  12. A new bismuth-doped fibre laser, emitting in the range 1625 – 1775 nm

    Energy Technology Data Exchange (ETDEWEB)

    Dianov, E M; Firstov, S V; Alyshev, S V; Riumkin, K E; Shubin, A V; Medvedkov, O I; Mel' kumov, M A [Fiber Optics Research Center, Russian Academy of Sciences, Moscow (Russian Federation); Khopin, V F; Gur' yanov, A N [G.G.Devyatykh Institute of Chemistry of High-Purity Substances, Russian Academy of Sciences, Nizhnii Novgorod (Russian Federation)

    2014-06-30

    CW lasing of a Bi-doped germanosilicate fibre in a wavelength range that covers the spectral region between the emission bands of Er and Tm fibre lasers has been demonstrated for the first time. (letters)

  13. Hybrid fluorescent layer emitting polarized light

    Science.gov (United States)

    Mohammadimasoudi, Mohammad; Beeckman, Jeroen; Hens, Zeger; Neyts, Kristiaan

    2017-07-01

    Semiconductor nanorods have anisotropic absorption and emission properties. In this work a hybrid luminescent layer is produced based on a mixture of CdSe/CdS nanorods dispersed in a liquid crystal that is aligned by an electric field and polymerized by UV illumination. The film emits light with polarization ratio 0.6 (polarization contrast 4:1). Clusters of nanorods in liquid crystal can be avoided by applying an AC electric field with sufficient amplitude. This method can be made compatible with large-scale processing on flexible transparent substrates. Thin polarized light emitters can be used in LCD backlights or solar concentrators to increase the efficiency.

  14. Hybrid fluorescent layer emitting polarized light

    Directory of Open Access Journals (Sweden)

    Mohammad Mohammadimasoudi

    2017-07-01

    Full Text Available Semiconductor nanorods have anisotropic absorption and emission properties. In this work a hybrid luminescent layer is produced based on a mixture of CdSe/CdS nanorods dispersed in a liquid crystal that is aligned by an electric field and polymerized by UV illumination. The film emits light with polarization ratio 0.6 (polarization contrast 4:1. Clusters of nanorods in liquid crystal can be avoided by applying an AC electric field with sufficient amplitude. This method can be made compatible with large-scale processing on flexible transparent substrates. Thin polarized light emitters can be used in LCD backlights or solar concentrators to increase the efficiency.

  15. In situ electron beam irradiated rapid growth of bismuth nanoparticles in bismuth-based glass dielectrics at room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Shiv Prakash; Karmakar, Basudeb, E-mail: basudebk@cgcri.res.in [Central Glass and Ceramic Research Institute (CSIR, India), Glass Science and Technology Section, Glass Division (India)

    2011-09-15

    In this study, in situ control growth of bismuth nanoparticles (Bi{sup 0} NPs) was demonstrated in bismuth-based glass dielectrics under an electron beam (EB) irradiation at room temperature. The effects of EB irradiation were investigated in situ using transmission electron microscopy (TEM), selected-area electron diffraction and high-resolution transmission electron microscopy. The EB irradiation for 2-8 min enhanced the construction of bismuth nanoparticles with a rhombohedral structure and diameter of 4-9 nm. The average particle size was found to increase with the irradiation time. Bismuth metal has a melting point of 271 Degree-Sign C and this low melting temperature makes easy the progress of energy induced structural changes during in situ TEM observations. This is a very useful technique in nano-patterning for integrated optics and other applications.

  16. Studies on bismuth carboxylates—synthesis and characterization of a new structural form of bismuth(III) dipicolinate

    Indian Academy of Sciences (India)

    O Anjaneyulu; K C Kumara Swamy

    2011-03-01

    Synthesis and X-ray structure of a new bismuth dipicolinate cooordination polymer, {[Bi((2,6-O2C)2C5H3N)((2-HO2C-6-O2C)C5H3N)(H2O)]2.5H2O} (7) are presented. Compound 7 has dimeric units with a Bi2O2 skeleton that are linked by additional weak Bi-O interactions leading to a polymeric structure. The overall coordination number at bismuth is 9 [two Bi-N and seven Bi-O bonds]. New routes to a second crystalline modification (4′) of the previously reported coordination polymer, bismuth tris(picolinate), [Bi(2-O2C-C5H4N)3] (4), are described; bond parameters in the two crystalline forms (4 and 4′) are compared. In both the compounds 4′ and 7, bismuth has a distorted tricapped trigonal prismatic geometry.

  17. Lifshitz topological transitions, induced by doping and deformation in single-crystal bismuth wires

    Science.gov (United States)

    Nikolaeva, A. A.; Konopko, L. A.; Huber, T. E.; Kobylianskaya, A. K.; Para, Gh. I.

    2017-02-01

    The features associated with the manifestation of Lifshitz electron topological transitions (ETT) in glass-insulated bismuth wires upon qualitative changes to the topology of the Fermi surface are investigated. The variation of the energy spectrum parameters was implemented by doping Bi with an acceptor impurity Sn and using elastic strain of up to 2%, relative to the elongation in the weakly-doped p-type Bi wires. Pure and doped glass-insulated single-crystal bismuth with different diameters and (1011) orientations along the axis were prepared by the Ulitovsky liquid phase casting method. For the first time, ETT-induced anomalies are observed along the temperature dependences of the thermoemf α(T) as triple-changes of the α sign (given heavy doping of Bi wires with an acceptor impurity Sn). The concentration and energy position of the Σ-band given a high degree of bismuth doping with Sn was assessed using the Shubnikov-de Haas effect oscillations, which were detected both from L-electrons and from T-holes in magnetic fields of up to 14 T. It is shown that the Lifshitz electron-topological transitions with elastic deformation of weakly-doped p-type Bi wires are accompanied by anomalies along the deformation dependences of the thermoemf at low temperatures. The effect is interpreted in terms of the formation of a selective scattering channel of L-carriers into the T-band with a high density of states, which is in good agreement with existing theoretical ETT models.

  18. Study on surface modification of bismuth nanoparticles%纳米铋的表面改性研究

    Institute of Scientific and Technical Information of China (English)

    罗洁; 卢业玉; 余林

    2012-01-01

    The adsorption amounts of three types of surfactants, i.e.stearic acid (SA),oleic acid (OA), and cetyltrimethylam-monium bromide (CTAB), on the surface of bismuth nanoparticles were investigated, in order to select the best surface modifier. Effects of various factors on modification of bismuth nanoparticles with stearic acid were discussed, and optimal modification conditions were obtained as follows: dosage of stearic acid was 10% (relative to the mass of bismuth powder) ,pH=5~6, and modification time was 1 h.Under these conditions,the modified bismuth nanoparticles had good wetting and dispersity in liquid paraffin and the powder was changed from hydrophilicity to hydrophobicity.FT-IR and XRD results showed the organic long-chain group of stearic acid grafted onto the surface of bismuth nanoparticles by chemical bonds; the crystal type of bismuth nanoparticles was not changed, but the grain diameter was decreased periodically.%测定了3种表面活性剂硬脂酸(SA)、油酸(OA)和十六烷基三甲基溴化铵(CTAB)在纳米铋表面的吸附量,进而选出最佳表面改性剂.研究了硬脂酸改性纳米铋粉各种因素对改性效果的影响,确定最佳工艺条件:改性剂用量为10%(相对于铋粉质量),pH为5~6,改性时间为1h.此条件下,改性后的纳米铋粉能在液体石蜡中润湿和分散,表明改性后粉体由亲水性变为亲油性.红外光谱(FT-IR)分析及X射线衍射(XRD)分析结果表明,硬脂酸有机长链基团成功地以化学键结合在纳米铋表面,改性后的铋粒子未发生晶型改变,只是粒径略有降低.

  19. Light-Emitting Pickles

    Science.gov (United States)

    Vollmer, M.; Mollmann, K-P.

    2015-01-01

    We present experiments giving new insights into the classical light-emitting pickle experiment. In particular, measurements of the spectra and temperatures, as well as high-speed recordings, reveal that light emission is connected to the polarity of the electrodes and the presence of hydrogen.

  20. Red Emitting VCSEL

    Science.gov (United States)

    Jetter, Michael; Roßbach, Robert; Michler, Peter

    This chapter describes the progress in development of vertical-cavity surface-emitting lasers (VCSEL) emitting in the red spectral region around 650 nm for data transmission over polymer optical fibers (POF). First, growth issues of red VCSEL using two different material systems, namely AlGaAs and AlGaInP, are introduced. In particular, the optical and electrical state-of-the-art characteristics as low threshold currents ({≤} 1 mA) and high output powers (several mW) are presented with a special focus on emission wavelength. Also the thermal budget and heat removal in the devices are pointed out with regard to the geometry of the VCSEL. Small-signal modulation response in terms of maximum resonance frequency in dependance on temperature behavior are discussed. Applications of these devices in optical interconnects are described and digital data transmission at data rates up to 2.1 Gbit/s over step-index POF is reported. These properties make red emitting VCSEL perfectly suited for high-speed low power consuming light sources for optical data communication via POF. By introducing InP quantum dots as gain material in red emitting VCSEL nearly temperature independent record low threshold current densities of around 10 A/cm2 could be observed.

  1. Light-Emitting Pickles

    Science.gov (United States)

    Vollmer, M.; Mollmann, K-P.

    2015-01-01

    We present experiments giving new insights into the classical light-emitting pickle experiment. In particular, measurements of the spectra and temperatures, as well as high-speed recordings, reveal that light emission is connected to the polarity of the electrodes and the presence of hydrogen.

  2. China Plays an Important Role in the World Bismuth Market Place

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>Available statistics shows that China not only has the world largest bismuth deposit but also is the world largest producer, exporter and consumer country. Particularly in the recent three years, China’s production and supply as well as the related policy changes has become a major factor in the bismuth market price fluctuations. China’s bismuth ore production in the recent two years has been kept stable and China’s output of bismuth ore concentrates accounts for

  3. Laboratory-Scale Bismuth Phosphate Extraction Process Simulation To Track Fate of Fission Products

    Energy Technology Data Exchange (ETDEWEB)

    Serne, R. JEFFREY; Lindberg, Michael J.; Jones, Thomas E.; Schaef, Herbert T.; Krupka, Kenneth M.

    2007-02-28

    Recent field investigation that collected and characterized vadose zone sediments from beneath inactive liquid disposal facilities at the Hanford 200 Areas show lower than expected concentrations of a long-term risk driver, Tc-99. Therefore laboratory studies were performed to re-create one of the three processes that were used to separate the plutonium from spent fuel and that created most of the wastes disposed or currently stored in tanks at Hanford. The laboratory simulations were used to compare with current estimates based mainly on flow sheet estimates and spotty historical data. Three simulations of the bismuth phosphate precipitation process show that less that 1% of the Tc-99, Cs-135/137, Sr-90, I-129 carry down with the Pu product and thus these isotopes should have remained within the metals waste streams that after neutralization were sent to single shell tanks. Conversely, these isotopes should not be expected to be found in the first and subsequent cycle waste streams that went to cribs. Measurable quantities (~20 to 30%) of the lanthanides, yttrium, and trivalent actinides (Am and Cm) do precipitate with the Pu product, which is higher than the 10% estimate made for current inventory projections. Surprisingly, Se (added as selenate form) also shows about 10% association with the Pu/bismuth phosphate solids. We speculate that the incorporation of some Se into the bismuth phosphate precipitate is caused by selenate substitution into crystal lattice sites for the phosphate. The bulk of the U daughter product Th-234 and Np-237 daughter product Pa-233 also associate with the solids. We suspect that the Pa daughter products of U (Pa-234 and Pa-231) would also co-precipitate with the bismuth phosphate induced solids. No more than 1 % of the Sr-90 and Sb-125 should carry down with the Pu product that ultimately was purified. Thus the current scheme used to estimate where fission products end up being disposed overestimates by one order of magnitude the

  4. Vibration Monitoring Using Fiber Optic Sensors in a Lead-Bismuth Eutectic Cooled Nuclear Fuel Assembly.

    Science.gov (United States)

    De Pauw, Ben; Lamberti, Alfredo; Ertveldt, Julien; Rezayat, Ali; van Tichelen, Katrien; Vanlanduit, Steve; Berghmans, Francis

    2016-04-21

    Excessive fuel assembly vibrations in nuclear reactor cores should be avoided in order not to compromise the lifetime of the assembly and in order to prevent the occurrence of safety hazards. This issue is particularly relevant to new reactor designs that use liquid metal coolants, such as, for example, a molten lead-bismuth eutectic. The flow of molten heavy metal around and through the fuel assembly may cause the latter to vibrate and hence suffer degradation as a result of, for example, fretting wear or mechanical fatigue. In this paper, we demonstrate the use of optical fiber sensors to measure the fuel assembly vibration in a lead-bismuth eutectic cooled installation which can be used as input to assess vibration-related safety hazards. We show that the vibration characteristics of the fuel pins in the fuel assembly can be experimentally determined with minimal intrusiveness and with high precision owing to the small dimensions and properties of the sensors. In particular, we were able to record local strain level differences of about 0.2 μϵ allowing us to reliably estimate the vibration amplitudes and modal parameters of the fuel assembly based on optical fiber sensor readings during different stages of the operation of the facility, including the onset of the coolant circulation and steady-state operation.

  5. Vibration Monitoring Using Fiber Optic Sensors in a Lead-Bismuth Eutectic Cooled Nuclear Fuel Assembly

    Directory of Open Access Journals (Sweden)

    Ben De Pauw

    2016-04-01

    Full Text Available Excessive fuel assembly vibrations in nuclear reactor cores should be avoided in order not to compromise the lifetime of the assembly and in order to prevent the occurrence of safety hazards. This issue is particularly relevant to new reactor designs that use liquid metal coolants, such as, for example, a molten lead-bismuth eutectic. The flow of molten heavy metal around and through the fuel assembly may cause the latter to vibrate and hence suffer degradation as a result of, for example, fretting wear or mechanical fatigue. In this paper, we demonstrate the use of optical fiber sensors to measure the fuel assembly vibration in a lead-bismuth eutectic cooled installation which can be used as input to assess vibration-related safety hazards. We show that the vibration characteristics of the fuel pins in the fuel assembly can be experimentally determined with minimal intrusiveness and with high precision owing to the small dimensions and properties of the sensors. In particular, we were able to record local strain level differences of about 0.2 μϵ allowing us to reliably estimate the vibration amplitudes and modal parameters of the fuel assembly based on optical fiber sensor readings during different stages of the operation of the facility, including the onset of the coolant circulation and steady-state operation.

  6. Direct numerical simulation and statistical analysis of turbulent convection in lead-bismuth

    Energy Technology Data Exchange (ETDEWEB)

    Otic, I.; Grotzbach, G. [Forschungszentrum Karlsruhe GmbH, Institut fuer Kern-und Energietechnik (Germany)

    2003-07-01

    Improved turbulent heat flux models are required to develop and analyze the reactor concept of an lead-bismuth cooled Accelerator-Driven-System. Because of specific properties of many liquid metals we have still no sensors for accurate measurements of the high frequency velocity fluctuations. So, the development of the turbulent heat transfer models which are required in our CFD (computational fluid dynamics) tools needs also data from direct numerical simulations of turbulent flows. We use new simulation results for the model problem of Rayleigh-Benard convection to show some peculiarities of the turbulent natural convection in lead-bismuth (Pr = 0.025). Simulations for this flow at sufficiently large turbulence levels became only recently feasible because this flow requires the resolution of very small velocity scales with the need for recording long-wave structures for the slow changes in the convective temperature field. The results are analyzed regarding the principle convection and heat transfer features. They are also used to perform statistical analysis to show that the currently available modeling is indeed not adequate for these fluids. Basing on the knowledge of the details of the statistical features of turbulence in this convection type and using the two-point correlation technique, a proposal for an improved statistical turbulence model is developed which is expected to account better for the peculiarities of the heat transfer in the turbulent convection in low Prandtl number fluids. (authors)

  7. Prognostic Value of Bismuth Typing and Modified T-stage in Hilar Cholangiocarcinoma

    Directory of Open Access Journals (Sweden)

    Shengen Yi

    2015-01-01

    Conclusion: The majority of our patients with HCC were characterized as Subtype IV in Bismuth typing and Stage T3 in modified T-stage. Both Bismuth typing and modified T-stage showed prognostic value in HCC. Compared with Bismuth typing, modified T-stage is a better indicator of the resectability of HCC.

  8. Controlled synthesis of bismuth oxyiodide toward optimization of photocatalytic performance

    Energy Technology Data Exchange (ETDEWEB)

    Liao, Chenxing; Ma, Zhijun [State Key Laboratory of Luminescent Materials and Devices, School of Materials Science and Engineering, South China University of Technology, Wushan Road 381, Guangzhou 510641 (China); Chen, Xiaofeng, E-mail: chenxf@scut.edu.c [Biomaterials Research Institute, School of Materials Science and Engineering, South China University of Technology, Wushan Road 381, Guangzhou 510641 (China); He, Xin [School of Applied Physics and Materials, Wuyi University, Jiangmen 529020 (China); Qiu, Jianrong, E-mail: qjr@scut.edu.cn [State Key Laboratory of Luminescent Materials and Devices, School of Materials Science and Engineering, South China University of Technology, Wushan Road 381, Guangzhou 510641 (China)

    2016-11-30

    Highlights: • Different bismuth oxyiodide was synthesized. • The hollow Bi{sub 4}O{sub 5}I{sub 2} microspheres was obtained. • Formation mechanism of the hollow structure was discussed in detail. - Abstract: A new investigation on the variation rule of the structure, morphology, chemical composition and photocatalytic performance of bismuth oxyiodide synthesized by solvothermal method as a function of reaction conditions was performed here. The composition and morphology of the product could be determined by X-ray diffraction, thermogravimetric analysis and scanning electron microscopy. The results revealed that the particle size together with content of iodide in bismuth oxyiodide decrease with the increase of the concentration of reaction precursors. Hollow Bi{sub 4}O{sub 5}I{sub 2} microsphere with specific surface area as high as 120.88 m{sup 2} g{sup −1} can be easily synthesized when the concentration of the reaction precursors finally increased to 62.5 mM. Photocatalytic water purification performance of the as-prepared samples was evaluated by using Rhodamine B (RhB) as a model contaminant. The results revealed that the hollow Bi{sub 4}O{sub 5}I{sub 2} exhibited the best performance among all the bismuth oxyodide synthesized here for the degradation of RhB under visible light irradiation. Meanwhile, the formation mechanism of the hierarchical hollow structure of bismuth oxyiodide was investigated by the dissolution-recrystallization mechanism.

  9. Bismuth X-ray absorber studies for TES microcalorimeters

    Energy Technology Data Exchange (ETDEWEB)

    Sadleir, J.E. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States) and University of Illinois Physics Department, Urbana, IL 61801 (United States)]. E-mail: sadleir@milkyway.gsfc.nasa.gov; Bandler, S.R. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Brekosky, R.P. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Chervenak, J. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Figueroa-Feliciano, E. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Finkbeiner, F. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Iyomoto, N. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Kelley, R.L. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Kilbourne, C.A. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); King, J.M. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Porter, F.S. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Robinson, I.K. [University of Illinois Physics Department, Urbana, IL 61801 (United States); Saab, T. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Talley, D.J. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2006-04-15

    Bismuth's large atomic number and low carrier density makes it an attractive X-ray absorber material for microcalorimeters. Bismuth's long Fermi wavelength and long mean free paths have motivated much interest in the fabrication of high quality bismuth films to study quantum size effects. Despite such incentives, fabrication of high quality bismuth films has proven difficult, and measured properties of such films are highly variable in the literature. Implementing a bismuth deposition process for TES (superconducting Transition Edge Sensor) device fabrication presents additional challenges particularly at interfaces due to the inherent granularity and surface roughness of its films, its low melting point, and its tendency to diffuse and form undesired intermetallic phases. We report observations of Bi-Cu and Bi-Au diffusion in our devices correlating with large shifts in T{sub c} (superconducting transition temperature). Using SEM and in situ R vs T annealing experiments we have been able to study these diffusion processes and identify their activation temperatures.

  10. Photoreductive generation of amorphous bismuth nanoparticles using polysaccharides--bismuth-cellulose nanocomposites.

    Science.gov (United States)

    Breitwieser, Doris; Kriechbaum, Margit; Ehmann, Heike M A; Monkowius, Uwe; Coseri, Sergiu; Sacarescu, Liviu; Spirk, Stefan

    2015-02-13

    A simple and highly reproducible synthesis of amorphous bismuth nanoparticles incorporated into a polysaccharide matrix using a photoreduction process is presented. As precursor for the generation of the Bi nanoparticles, organosoluble triphenylbismuth is used. The precursor is dissolved in toluene and mixed with a hydrophobic organosoluble polysaccharide, namely trimethylsilyl cellulose (TMSC) with high DSSi. The solution is subjected to UV exposure, which induces the homolytic cleavage of the bismuth-carbon bond in BiPh3 resulting in the formation of Bi(0) and phenyl radicals. The aggregation of the Bi atoms can be controlled in the TMSC matrix and yields nanoparticles of around 20 nm size as proven by TEM. The phenyl radicals undergo recombination to form small organic molecules like benzene and biphenyl, which can be removed from the nanocomposite after lyophilization and exposure to high vacuum. Finally, the TMSC matrix is converted to cellulose after exposure to HCl vapors, which remove the trimethylsilyl groups from the TMSC derivative. Although TMSC is converted to cellulose, the formed TMS-OH is not leaving the nanocomposite but reacts instead with surface oxide layer of the Bi nanoparticles to form silylated Bi nanoparticles as proven by TEM/EDX.

  11. Bismuth nanoparticles for phenolic compounds biosensing application.

    Science.gov (United States)

    Mayorga-Martinez, Carmen C; Cadevall, Miquel; Guix, Maria; Ros, Josep; Merkoçi, Arben

    2013-02-15

    The rapid determination of trace phenolic compounds is of great importance for evaluating the total toxicity of contaminated water samples. Nowadays, electrochemical tyrosinase (Tyr) based biosensors constitute a promising technology for the in situ monitoring of phenolic compounds because of their advantages such as high selectivity, low production cost, promising response speed, potential for miniaturization, simple instrumentation and easy automatization. A mediator-free amperometric biosensor for phenolic compounds detection based on the combination of bismuth nanoparticles (BiNPs) and Tyr for phenol detections will be hereby reported. This is achieved through the integration of BiNPs/Tyr onto the working electrode of a screen printed electrode (SPE) by using glutaraldehyde as a cross-linking agent. BiNPs/Tyr biosensor is evaluated by amperometric measurements at -200 mV DC and a linear range of up to 71 μM and 100 μM and a correlation coefficient of 0.995 and 0.996 for phenol and catechol, respectively. The very low DC working potential ensures the avoidance of interferences making this biosensor an advantageous device for real sample applications. In addition, the response mechanism including the effect of BiNPs based on electrochemical studies and optical characterizations will be also discussed. The obtained results may open the way to many other BiNPs applications in the biosensing field.

  12. LMO dielectronic resonances in highly charged bismuth

    Science.gov (United States)

    Smiga, Joseph; Gillaspy, John; Podpaly, Yuri; Ralchenko, Yuri

    2016-05-01

    Dielectronic resonances from high-Z elements are important for the analysis of high temperature plasmas. Thus, the extreme ultraviolet spectra of highly charged bismuth were measured using the NIST electron beam ion trap (EBIT) at beam energies ranging from 8.7 keV to 9.2 keV. The measured intensity ratios between forbidden magnetic-dipole lines in Bi64+ and Bi63+ show strong resonance features. The experimental data were compared to theoretical predictions from a large-scale collisional-radiative model with the code NOMAD, and good agreement was found that allowed the identification of observed resonance features as the LMO inner-shell dielectronic resonances. It is common practice in EBIT experiments that ions are periodically dumped from the trap and replaced. However, in this particular experiment, the contents of the trap were not dumped for the duration of each 10 minute sampling. The effects of trap stability were studied and a small but noticeable shift in beam energy over time was observed. Potential explanations for this are considered.

  13. Laser Spectroscopy of Neutron Rich Bismuth Isotopes

    CERN Multimedia

    2002-01-01

    %IS344 :\\\\ \\\\ The aim of the experiment is to measure the optical isotope shifts and hyperfine structures of bismuth isotopes across the N=126 shell closure in order to extract the change in mean square charge radii ($\\delta\\langle r^{2}\\rangle$) and static moments. These include the first isotones of lead to be measured directly above the shell closure and will provide new information on the systematics of the kink ($\\delta\\langle r^{2}\\rangle)$ seen in the lead isotopic chain. After two very successful runs the programme has been extended to include the neutron deficient isotopes below $^{201}$Bi to study the systematics across the $i_{13/2}$ neutron sub-shell closure at N=118.\\\\ \\\\ During the initial 2 runs (9 shifts) the isotope shifts and hyperfine structures of three new isotopes, $ ^{210,212,213}$Bi and the 9$^{-}$ isomer of $^{210}$Bi have been measured. The accuracy of the previous measurements of $^{205,206,208}$Bi have been greatly improved. The samples of $ ^{208,210,210^{m}}$Bi were prepared by c...

  14. Bismuth iron oxide thin films using atomic layer deposition of alternating bismuth oxide and iron oxide layers

    Energy Technology Data Exchange (ETDEWEB)

    Puttaswamy, Manjunath; Vehkamäki, Marko [University of Helsinki, Department of Chemistry, P.O. Box 55, FI-00014 Helsinki (Finland); Kukli, Kaupo, E-mail: kaupo.kukli@helsinki.fi [University of Helsinki, Department of Chemistry, P.O. Box 55, FI-00014 Helsinki (Finland); University of Tartu, Institute of Physics, W. Ostwald 1, EE-50411 Tartu (Estonia); Dimri, Mukesh Chandra [National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, EE-12618 Tallinn (Estonia); Kemell, Marianna; Hatanpää, Timo; Heikkilä, Mikko J. [University of Helsinki, Department of Chemistry, P.O. Box 55, FI-00014 Helsinki (Finland); Mizohata, Kenichiro [University of Helsinki, Department of Physics, P.O. Box 64, FI-00014 Helsinki (Finland); Stern, Raivo [National Institute of Chemical Physics and Biophysics, Akadeemia tee 23, EE-12618 Tallinn (Estonia); Ritala, Mikko; Leskelä, Markku [University of Helsinki, Department of Chemistry, P.O. Box 55, FI-00014 Helsinki (Finland)

    2016-07-29

    Bismuth iron oxide films with varying contributions from Fe{sub 2}O{sub 3} or Bi{sub 2}O{sub 3} were prepared using atomic layer deposition. Bismuth (III) 2,3-dimethyl-2-butoxide, was used as the bismuth source, iron(III) tert-butoxide as the iron source and water vapor as the oxygen source. The films were deposited as stacks of alternate Bi{sub 2}O{sub 3} and Fe{sub 2}O{sub 3} layers. Films grown at 140 °C to the thickness of 200–220 nm were amorphous, but crystallized upon post-deposition annealing at 500 °C in nitrogen. Annealing of films with intermittent bismuth and iron oxide layers grown to different thicknesses influenced their surface morphology, crystal structure, composition, electrical and magnetic properties. Implications of multiferroic performance were recognized in the films with the remanent charge polarization varying from 1 to 5 μC/cm{sup 2} and magnetic coercivity varying from a few up to 8000 A/m. - Highlights: • Bismuth iron oxide thin films were grown by atomic layer deposition at 140 °C. • The major phase formed in the films upon annealing at 500 °C was BiFeO{sub 3}. • BiFeO{sub 3} films and films containing excess Bi favored electrical charge polarization. • Slight excess of iron oxide enhanced saturative magnetization behavior.

  15. Inexpensive laser-induced surface modification in bismuth thin films

    Energy Technology Data Exchange (ETDEWEB)

    Contreras, A. Reyes [Facultad de Ciencias, Universidad Autónoma del Estado de México, Carretera Toluca, Ixtlahuaca Kilómetro 15.5, C.P. 50200 Edo. de México (Mexico); Hautefeuille, M., E-mail: mathieu_h@ciencias.unam.mx [Facultad de Ciencias, Universidad Nacional Autónoma de México, Avenida Universidad 3000, Circuito Exterior S/N, Coyoacán, Ciudad Universitaria, C.P. 04510 D.F. Mexico (Mexico); García, A. Esparza [Fotofísica y Películas Delgadas, Departamento de Tecnociencias, CCADET-UNAM, Circuito exterior s/n C.P. 04510 Cd. Universitaria, D.F. Mexico (Mexico); Mejia, O. Olea [Centro Conjunto de Investigación en Química Sustentable UAEM-UNAM, Carretera Toluca-Atlacomulco, Km 14.5, Unidad El Rosedal, 50200 San Cayetano, Estado de México (Mexico); López, M.A. Camacho [Facultad de Química, Universidad Autónoma del Estado de México, Tollocan s/n, esq. Paseo Colón, Toluca, Estado de México 50110 (Mexico)

    2015-05-01

    Highlights: • Laser-induced microbumps were formed on bismuth films using a simple, low-cost, laser setup. • The patterns, similar to those typically obtained with high-power lasers, were characterized. • Control of laser ablation conditions is critical in the fabrication of surface microbumps. - Abstract: In this work, we present results on texturing a 500 nm thick bismuth film, deposited by sputtering onto a glass slide using a low-cost homemade, near-infrared pulsed laser platform. A 785 nm laser diode of a CD–DVD pickup head was precisely focused on the sample mounted on a motorized two-axis translation stage to generate localized surface microbumps on the bismuth films. This simple method successfully transferred desired micropatterns on the films in a computer-numerical control fashion. Irradiated zones were characterized by atomic force microscopy and scanning electron microscopy. It was observed that final results are strongly dependent on irradiation parameters.

  16. Characterization of bismuth nanospheres deposited by plasma focus device

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, M., E-mail: cscientific2@aec.org.sy [IBA Laboratory, Chemistry Department, Atomic Energy Commission of Syria, P.O. Box 6091, Damascus (Syrian Arab Republic); Al-Hawat, Sh.; Akel, M. [Physics Department, Atomic Energy Commission of Syria, P.O. Box 6091, Damascus (Syrian Arab Republic); Mrad, O. [Chemistry Department, Atomic Energy Commission of Syria, P.O. Box 6091, Damascus (Syrian Arab Republic)

    2015-02-14

    A new method for producing thin layer of bismuth nanospheres based on the use of low energy plasma focus device is demonstrated. Various techniques such as scanning electron microscopy, Rutherford backscattering spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and Raman spectroscopy have been used to characterize the morphology and the composition of the nanospheres. Experimental parameters may be adjusted to favour the formation of bismuth nanospheres instead of microspheres. Therefore, the formation of large surface of homogeneous layer of bismuth nanospheres with sizes of below 100 nm can be obtained. The natural snowball phenomenon is observed to be reproduced in nanoscale where spheres roll over the small nanospheres and grow up to bigger sizes that can reach micro dimensions. The comet-like structure, a reverse phenomenon to snowball is also observed.

  17. Dependence of optical properties of calcium bismuthates on synthesis conditions

    Science.gov (United States)

    Shtarev, D. S.; Shtareva, A. V.

    2016-08-01

    The article studies optical properties of calcium bismuthate nanoparticles of different composition. For the first time the synthesis of these compounds was produced by the pyrolysis of organic precursors using an organic solvent. Characterization of particles was made by scanning electron microscopy and X-ray analysis. The optical properties were investigated by diffuse reflectance spectroscopy (DRS). It is shown that the type of crystal lattice of the particles of calcium bismuthate determines the possibility to control the optical properties of nanoparticles by varying their composition. The conclusions about the production process and the composition of calcium bismuthate, the most promising for use as a photocatalyst of visible light and solar cells, were made.

  18. Bismuth Substituted Yttrium Iron Garnet Single Crystal Films Prepared by Sol-gel Method

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Magneto-optic Faraday rotation effect and the amount of bismuth substituted in yttrium iron garnet single crystal films prepared by gel-coating on modified gadolinium-gallium garnet substrates are investigated, where the gel is synthesized by a sol-gel reaction of nitrates and ethylene glycol. The coated gel is annealed in air at temperatures up to 660℃ for 4h, which is about 300℃ lower than that of liquid-phase epitaxy. The maximum amount of Bi substitution is x=2.7 and the crystallization temperature of garnet phase decreases with the increase of x down to 520℃ for x=2.7. In this film, a huge Faraday rotation of -8.1×104 (°)/cm at λ=0.633μm is obtained.

  19. Electrical and optical properties of gadolinium doped bismuth ferrite nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, A., E-mail: soumen.basu@phy.nitdgp.ac.in; Banerjee, M., E-mail: soumen.basu@phy.nitdgp.ac.in; Basu, S., E-mail: soumen.basu@phy.nitdgp.ac.in [Department of Physics, National Institute of Technology, Durgapur-713209 (India); Pal, M. [CSIR-Central Mechanical Engineering Research Institute, Durgapur-713209 (India)

    2014-04-24

    Multiferroic bismuth ferrite (BFO) and gadolinium (Gd) doped bismuth ferrite had been synthesized by a sol-gel method. Particle size had been estimated by Transmission electron microscopy (TEM) and found to decrease with Gd doping. We studied the temperature and frequency dependence of impedance and electric modulus and calculated the grain and grain boundary resistance and capacitance of the investigated samples. We observed that electrical activation energy increases for all the doped samples. Optical band gap also increases for the doped samples which can be used in photocatalytic application of BFO.

  20. Microscopic and voltammetric properties of lustrous bismuth deposits

    OpenAIRE

    Krolicka, Agnieszka; Bobrowski, Andrzej; Pamuła, Elżbieta

    2010-01-01

    A comparison of lustrous bismuth films, plated at glassy carbon, platinum and gold supports, is presented. The voltammetric performance of preplated bismuth film electrodes was tested using 50 μg/L In(III) and 50 μg/L Pb(II) solutions in 0.1 M acetic buffer in square wave and differential pulse modes. The influence of support material, plating solution concentration and storing conditions on the voltammetric response of BiFEs is discussed. The results of microscopic examination...

  1. Temperature monitoring using fibre optic sensors in a lead-bismuth eutectic cooled nuclear fuel assembly

    Energy Technology Data Exchange (ETDEWEB)

    De Pauw, B., E-mail: bdepauw@vub.ac.be [Vrije Universiteit Brussel (VUB), Brussels Photonics Team (B-Phot), Brussels (Belgium); Vrije Universiteit Brussel (VUB), Acoustics and Vibration Research Group (AVRG), Brussels (Belgium); Belgian Nuclear Research Centre, (SCK-CEN), Boeretang 200, Mol (Belgium); Lamberti, A.; Ertveldt, J.; Rezayat, A.; Vanlanduit, S. [Vrije Universiteit Brussel (VUB), Acoustics and Vibration Research Group (AVRG), Brussels (Belgium); Van Tichelen, K. [Belgian Nuclear Research Centre, (SCK-CEN), Boeretang 200, Mol (Belgium); Berghmans, F. [Vrije Universiteit Brussel (VUB), Brussels Photonics Team (B-Phot), Brussels (Belgium)

    2016-02-15

    Highlights: • We demonstrate the use of optical fibre sensors in lead-bismuth cooled installations. • In this first of a kind experiment, we focus on temperature measurements of fuel rods • We acquire the surface temperature with a resolution of 30 mK. • We asses the condition of the installation during different steps of the operation. - Abstract: In-core temperature measurements are crucial to assess the condition of nuclear reactor components. The sensors that measure temperature must respond adequately in order, for example, to actuate safety systems that will mitigate the consequences of an undesired temperature excursion and to prevent component failure. This issue is exacerbated in new reactor designs that use liquid metals, such as for example a molten lead-bismuth eutectic, as coolant. Unlike water cooled reactors that need to operate at high pressure to raise the boiling point of water, liquid metal cooled reactors can operate at high temperatures whilst keeping the pressure at lower levels. In this paper we demonstrate the use of optical fibre sensors to measure the temperature distribution in a lead-bismuth eutectic cooled installation and we derive functional input e.g. the temperature control system or other systems that rely on accurate temperature actuation. This first-of-a-kind experiment demonstrates the potential of optical fibre based instrumentation in these environments. We focus on measuring the surface temperature of the individual fuel rods in the fuel assembly, but the technique can also be applied to other components or sections of the installation. We show that these surface temperatures can be experimentally measured with limited intervention on the fuel pin owing to the small geometry and fundamental properties of the optical fibres. The unique properties of the fibre sensors allowed acquiring the surface temperatures with a resolution of 30 mK. With these sensors, we assess the condition of the test section containing the fuel

  2. Hydrolysis studies on bismuth nitrate: synthesis and crystallization of four novel polynuclear basic bismuth nitrates.

    Science.gov (United States)

    Miersch, L; Rüffer, T; Schlesinger, M; Lang, H; Mehring, M

    2012-09-03

    Hydrolysis of Bi(NO(3))(3) in aqueous solution gave crystals of the novel compounds [Bi(6)O(4)(OH)(4)(NO(3))(5)(H(2)O)](NO(3)) (1) and [Bi(6)O(4)(OH)(4)(NO(3))(6)(H(2)O)(2)]·H(2)O (2) among the series of hexanuclear bismuth oxido nitrates. Compounds 1 and 2 both crystallize in the monoclinic space group P2(1)/n but show significant differences in their lattice parameters: 1, a = 9.2516(6) Å, b = 13.4298(9) Å, c = 17.8471(14) Å, β = 94.531(6)°, V = 2210.5(3) Å(3); 2, a = 9.0149(3) Å, b = 16.9298(4) Å, c = 15.6864(4) Å, β = 90.129(3)°, V = 2394.06(12) Å(3). Variation of the conditions for partial hydrolysis of Bi(NO(3))(3) gave bismuth oxido nitrates of even higher nuclearity, [{Bi(38)O(45)(NO(3))(24)(DMSO)(26)}·4DMSO][{Bi(38)O(45)(NO(3))(24)(DMSO)(24)}·4DMSO] (3) and [{Bi(38)O(45)(NO(3))(24)(DMSO)(26)}·2DMSO][{Bi(38)O(45)(NO(3))(24)(DMSO)(24)}·0.5DMSO] (5), upon crystallization from DMSO. Bismuth oxido clusters 3 and 5 crystallize in the triclinic space group P1 both with two crystallographically independent molecules in the asymmetric unit. The following lattice parameters are observed: 3, a = 20.3804(10) Å, b = 20.3871(9) Å, c = 34.9715(15) Å, α = 76.657(4)°, β = 73.479(4)°, γ = 60.228(5)°, V = 12021.7(9) Å(3); 5, a = 20.0329(4) Å, b = 20.0601(4) Å, c = 34.3532(6) Å, α = 90.196(1)°, β = 91.344(2)°, γ = 119.370(2)°, V = 12025.8(4) Å(3). Differences in the number of DMSO molecules (coordinated and noncoordinated) and ligand (nitrate, DMSO) coordination modes are observed.

  3. Light Emitting Porous Silicon

    Science.gov (United States)

    1993-05-01

    ml - mm m lm m ~ m m ThO report Page 14 preparation method which has been originally described by Wohler [23] leads to a bright yellow substance with...Solid State Commun. 81, 307 (1992). [221 H. Kautsky, and H. Zocher, Z. Phys. 9,267 (1992). L TNO report Page 28 [231 F. Wohler , Lieb. Ann. 127, 275 (1863...Netherlands Fax + 31 70 328 09 61 Phone + 31 70 326 42 21 TNO- report copy no. e FEL-93eo047r Lh Emitting Porous Silicon sitho(s): DTICHMi.P.Th

  4. Bismuth centred magnetic perovskite: A projected multiferroic

    Energy Technology Data Exchange (ETDEWEB)

    Kundu, Asish K., E-mail: asish.k@gmail.com [Discipline of Physics, Indian Institute of Information Technology, Design and Manufacturing, Dumna Airport Road, Jabalpur 482005 (India); Seikh, Md. Motin [Department of Chemistry, Visva-Bharati University, Santiniketan, West Bengal 731235 (India); Nautiyal, Pranjal [Discipline of Mechanical Engineering, Indian Institute of Information Technology, Design and Manufacturing, Dumna Airport Road, Jabalpur 482005 (India)

    2015-03-15

    In recent time substantial attention has been initiated to understand the physics behind multiferroism and to design new multiferroic materials. BiMnO{sub 3} and BiFeO{sub 3} are the well-studied Bi-centred multiferroic oxides. BiMnO{sub 3} is a ferromagnetic–ferroelectric (metastable) phase and require drastic conditions to synthesize. However, lanthanum substituted BiMnO{sub 3} phases stabilized at ambient pressure. It is thus of major importance to increase the number of ferromagnetic perovskites with Bi cations that could be designed under ambient conditions. In this article, we have presented an up to date report of investigations on Bi-centred magnetic perovskites, a prospective material for multiferroic application. Central focus is concentrated on La{sub 0.5}Bi{sub 0.5}MnO{sub 3} perovskite with various substitutions at different levels. A few of these perovskites are found to be of practical importance e.g. La{sub 0.5}Bi{sub 0.5}Mn{sub 0.67}Co{sub 0.33}O{sub 3} with high dielectric permittivity coupled with ferromagnetism. A comprehensive analysis of different physical functionalities and their interrelation for a wide range of compositions of these Bi-centred perovskites is presented. It has been found that the complex magnetic behaviour originates from mixed valence metal ions. The ferroelectricity is associated with the 6s{sup 2} lone pair of Bi{sup 3+} cations. The magnetic ground state influences the dielectric properties reflecting the multiferroism in a single material. - Highlights: • Multiferroics have attracted increasing attention due to their possible device applications. • Bismuth centred magnetic perovskite is one kind of such promising multiferroic materials. • Ferromagnetic Bi-perovskites, which are synthesized at ambient conditions, have been discussed.

  5. Emulsion liquid membrane for selective extraction of Bi(III)

    Institute of Scientific and Technical Information of China (English)

    Bahram Mokhtari; Kobra Pourabdollah

    2015-01-01

    Di(2-ethylhexyl)phosphoric acid was used as extractant of bismuth ions from nitrate medium by emulsion liquid membrane, with Triton X-100 as the biodegradable surfactant in n-pentanol bulk membrane. The novelties and innovative points of this work are the application of emulsion liquid membrane for selective and efficient extraction of bismuth ions as wel as the relevant optimization procedures. The extraction of bismuth ions was evaluated by the yield of extraction. The experimental parameters were evaluated and optimized, including the ratio of di(2-ethylhexyl)phosphoric acid mass concentration to Triton X-100 (1.0%:0.5%), nature of diluent (n-pentanol), nature and concentration of stripping solution (sulfuric acid, 0.5 mol·L−1), stirring speed (1800 r·min−1) and equilibrium time of extraction (20 min), initial feed solution of bismuth (350 mg·L−1) and the volume ratio of internal stripping phase to membrane phase (14). The experimental parameters of kinetic extraction reveal that the bismuth ions can be extracted by 100%.

  6. Highly monodisperse bismuth nanoparticles and their three-dimensional superlattices.

    Science.gov (United States)

    Yarema, Maksym; Kovalenko, Maksym V; Hesser, Günter; Talapin, Dmitri V; Heiss, Wolfgang

    2010-11-01

    A simple and reproducible synthesis of highly monodisperse and ligand-protected bismuth nanoparticles (Bi NPs) is reported. The size of the single-crystalline and spherically shaped NPs is controlled between 11 and 22 nm mainly by the reaction temperature. The high uniformity of the NPs allows their self-assembly into long-range-ordered two- and three-dimensional superstructures.

  7. Ultrafast electronic dynamics in laser-excited crystalline bismuth

    Directory of Open Access Journals (Sweden)

    Chekalin S.

    2013-03-01

    Full Text Available Femtosecond spectroscopy was applied to capture complex dynamics of non equilibrium electrons in bismuth. Data analysis reveals significant wavevector dependence of electron-hole and electron-phonon coupling strength along the Γ-T direction of the Brillouin zone

  8. Phase transition of bismuth telluride thin films grown by MBE

    DEFF Research Database (Denmark)

    Fülöp, Attila; Song, Yuxin; Charpentier, Sophie

    2014-01-01

    A previously unreported phase transition between Bi2Te3 and Bi4Te3 in bismuth telluride grown by molecular beam epitaxy is recorded via XRD, AFM, and SIMS observations. This transition is found to be related to the Te/Bi beam equivalent pressure (BEP) ratio. BEP ratios below 17 favor the formation...

  9. Oxygen semi-permeability of erbia-stabilized bismuth oxide

    NARCIS (Netherlands)

    Bouwmeester, H.J.M.; Kruidhof, H.; Burggraaf, A.J.; Gellings, P.J.

    1992-01-01

    The isothermal permeability of oxygen through sintered dense disks of bismuth oxide stabilized with 25 mol% erbia (BE25) has been studied at 610–810°C and oxygen pressures of 0.0001–1 atm. It is concluded that the permeating flux is rate limited both by solid state diffusion of electron holes and by

  10. Light-Induced Absorption in Nominally Pure Bismuth Silicon Oxide

    Institute of Scientific and Technical Information of China (English)

    李飞飞; 许京军; 孔勇发; 黄辉; 张光寅; 杨春晖; 徐玉恒

    2001-01-01

    Light-induced absorption in the nominally pure bismuth silicon oxide is investigated experimentally and the result shows that it consists of transient and persistent parts. The experimental evidence is analysed based on the model of three groups of trap (donor) centres.

  11. Bismuth-lead oxide, a new highly conductive oxygen materials

    NARCIS (Netherlands)

    Honnart, F.; Boivin, J.C.; Thomas, D.; Vries, de K.J.

    1983-01-01

    The transport properties of an oxygen-deficient solid solution containing lead and bismuth oxides have been investigated. The conductivity is larger than 1 (ω× cm)−1 at 600 °C. Thermogalvanic measurements confirm that no significant electronic contribution occurs in the range 1–10−3atm p O2. The hea

  12. High ionic conductivity in confined bismuth oxide-based heterostructures

    DEFF Research Database (Denmark)

    Sanna, Simone; Esposito, Vincenzo; Christensen, Mogens

    2016-01-01

    Bismuth trioxide in the cubic fluorite phase (δ-Bi2O3) exhibits the highest oxygen ionic conductivity. In this study, we were able to stabilize the pure -Bi2O3 at low temperature with no addition of stabilizer but only by engineering the interface, using highly coherent heterostructures made...

  13. Nanometer bismuth oxide produced by resistance heating vapor oxidation

    Institute of Scientific and Technical Information of China (English)

    HU Han-xiang; QIU Ke-qiang

    2006-01-01

    Bismuth oxide has wide applications in superconductive material, photoelectric material, electronic ceramic, electrolyte, and catalysts. To produce ultrafine bismuth oxide powders, some costly heating sources, such as plasma, high frequency induction, electron beam or laser, have to be used in the conventional vapor oxidation methods. The vapor oxidation method was improved by adding a reducing agent in the reaction system, where heating source was resistance tubular oven, instead of special heat source requirement. Nanometer bismuth oxide was prepared at 1 000-1 140 ℃, and the particle characteristics were investigated by XRD, SEM, DTA, laser sedimentograph. With low oxygen concentration (less than 20%) in the carrier gas, the bismuth oxide particle was near-sphere β-Bi2O3 with uniform and fine particle size (d0.5=65 nm, GSD=1.42); while with higher oxygen content (more than 50%), the powders were mixture of Bi2O2CO3 and β-Bi2O3.

  14. Polymeric architectures of bismuth citrate based on dimeric building blocks

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Four bismuth complexes, (H2En)[Bi2(cit)2(H2O)4/3]·(H2O)x (1), (H2En)3[Bi2(cit)2Cl4]·(H2O)x (2), (HPy)2[Bi2(cit)2(H2O)8/5]·(H2O)x (3) and (H2En)[Bi2(cit)2](H2O)x (4) [cit = citrate4-; En = ethylenediamine; Py = pyridine] have been synthesized and crystallized. The crystal structures reveal that the basic building blocks in all of these complexes are bismuth citrate dimeric units which combine to form polymeric architectures. The embedded protonated ethylenediamine and pyridine moieties in the polymeric frameworks have been identified by X-ray crystallography and solid-state cross polarization/magic angle spinning (CP/MAS) 13C NMR. Based on the framework of complex 1, a structural model of a clinically used antiulcer drug, ranitidine bismuth citrate (RBC) was generated. The behavior of the protonated amine-bismuth citrate complexes in acidic aqueous solution has been studied by electrospray ionization-mass spectrometry (ESI-MS).

  15. Ultrafast electron diffraction studies of optically excited thin bismuth films

    Energy Technology Data Exchange (ETDEWEB)

    Rajkovic, Ivan

    2008-10-21

    This thesis contains work on the design and the realization of an experimental setup capable of providing sub-picosecond electron pulses for ultrafast electron diffraction experiments, and performing the study of ultrafast dynamics in bismuth after optical excitation using this setup. (orig.)

  16. Discovery of the thallium, lead, bismuth, and polonium isotopes

    Science.gov (United States)

    Fry, C.; Thoennessen, M.

    2013-05-01

    Forty-two thallium, forty-two lead, forty-one bismuth, and forty-two polonium isotopes have so far been observed; the discovery of these isotopes is described. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  17. Discovery of the thallium, lead, bismuth, and polonium isotopes

    CERN Document Server

    Fry, C

    2012-01-01

    Currently, forty-two thallium, forty-two lead, forty-one bismuth, and forty-two polonium isotopes have so far been observed; the discovery of these isotopes is discussed. For each isotope a brief summary of the first refereed publication, including the production and identification method, is presented.

  18. Bismuth Ferrite for Active Control of Surface Plasmon Polariton Modes

    DEFF Research Database (Denmark)

    Babicheva, Viktoriia; Zhukovsky, Sergei; Lavrinenko, Andrei

    2014-01-01

    We propose and investigate several layouts of m etal-insulator-metal waveguide with active core which can be utilized for dynamic switching in photonic integrated circuits. The active material, bismuth ferrite (BiFeO3), is sandwiched between metal plates and changes i ts refractive index through ...

  19. Bismuth-based oxide semiconductors: Mild synthesis and practical applications

    Science.gov (United States)

    Timmaji, Hari Krishna

    In this dissertation study, bismuth based oxide semiconductors were prepared using 'mild' synthesis techniques---electrodeposition and solution combustion synthesis. Potential environmental remediation and solar energy applications of the prepared oxides were evaluated. Bismuth vanadate (BiVO4) was prepared by electrodeposition and solution combustion synthesis. A two step electrosynthesis strategy was developed and demonstrated for the first time. In the first step, a Bi film was first electrodeposited on a Pt substrate from an acidic BiCl3 medium. Then, this film was anodically stripped in a medium containing hydrolyzed vanadium precursor, to generate Bi3+, and subsequent BiVO4 formation by in situ precipitation. The photoelectrochemical data were consistent with the in situ formation of n-type semiconductor films. In the solution combustion synthesis procedure, BiVO4 powders were prepared using bismuth nitrate pentahydrate as the bismuth precursor and either vanadium chloride or vanadium oxysulfate as the vanadium precursor. Urea, glycine, or citric acid was used as the fuel. The effect of the vanadium precursor on the photocatalytic activity of combustion synthesized BiVO 4 was evaluated in this study. Methyl orange was used as a probe to test the photocatalytic attributes of the combustion synthesized (CS) samples, and benchmarked against a commercial bismuth vanadate sample. The CS samples showed superior activity to the commercial benchmark sample, and samples derived from vanadium chloride were superior to vanadium oxysulfate counterparts. The photoelectrochemical properties of the various CS samples were also studied and these samples were shown to be useful both for environmental photocatalytic remediation and water photooxidation applications. Silver bismuth tungstate (AgBiW2O8) nanoparticles were prepared for the first time by solution combustion synthesis by using silver nitrate, bismuth nitrate, sodium tungstate as precursors for Ag, Bi, and W

  20. Liquid Scintillation Counting

    OpenAIRE

    Carlsson, Sten

    1993-01-01

    In liquid scintillation counting (LSC) we use the process of luminescense to detect ionising radiation emit$ed from a radionuclide. Luminescense is emission of visible light of nonthermal origin. 1t was early found that certain organic molecules have luminescent properties and such molecules are used in LSC. Today LSC is the mostwidespread method to detect pure beta-ernitters like tritium and carbon-14. 1t has unique properties in its efficient counting geometry, deteetability and the lack of...

  1. Bismuth tri-iodide radiation detector development

    Science.gov (United States)

    Gokhale, Sasmit S.

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

  2. Texture and anisotropy of ferroelectric bismuth titanate

    Science.gov (United States)

    Jones, Jacob Leo

    Ferroelectric bismuth titanate, Na0.5Bi4.5 Ti4O15, is a piezoelectric ceramic used as an electromechanical sensor in high temperature environments (T piezoelectric constant, d33, is relatively low in randomly oriented ceramics. Crystallographic texturing is often employed to increase the piezoelectric constant because the spontaneous polarization axes of the grains are better aligned. This research distinguishes between the crystallographic texture induced to the grains from tape casting and crystallographic texture induced to the ferroelectric domains from electrical poling. Novel quantitative approaches describe texture of both types independently using conventional and synchrotron X-ray sources as well as time-of-flight neutron diffraction with multiple detectors. Furthermore, methods are developed to describe the combined effect of a ferroelectric texture superimposed on a paraelectric texture. Texture of the paraelectric crystallographic axes was induced by novel processing approaches. An alternative to using plate-shaped template particles was developed utilizing calcined powder. Paraelectric texture develops from particle settling and strong surface energy anisotropy during sintering. The 00l textures induced from this process are on the order of two to four multiples of a random distribution. These textures create property anisotropies between the casting plane and normal directions of 6.4 and 5.7 in piezoelectric d33 constant and remanent polarization, respectively. Texture of the ferroelectric crystallographic axes was induced by electrical poling at different temperatures and in different orientations. Ceramics with an initial paraelectric texture can exhibit greater change in the domain volume fractions during electrical poling than randomly oriented ceramics. This is demonstrated by applying novel quantitative approaches to reflection X-ray spectra from many sample directions. Because orthorhombic Na0.5Bi 4.5Ti4O15 has two ferroelectric domains that

  3. Determining the background levels of bismuth in tissues of wild game birds: a first step in addressing the environmental consequences of using bismuth shotshells

    Energy Technology Data Exchange (ETDEWEB)

    Jayasinghe, R.; Tsuji, L.J.S.; Gough, W.A.; Karagatzides, J.D.; Perera, D.; Nieboer, E

    2004-11-01

    Bismuth shotshells have been approved as a 'nontoxic' alternative to lead in North America. Approval was based on a limited number of studies; even background levels of bismuth in wildfowl were unknown. We report on the concentration of bismuth (and lead) in muscle and liver tissues of wildfowl (Anas platyrhynchos, Anas acuta, Anas crecca, Branta canadensis, Chen caerulescens) harvested with lead shotshell. Average liver-bismuth levels detected in the present study (e.g., teal, 0.05 {mu}g/g dw; mallard, 0.09 {mu}g/g dw) suggest analytical error in other studies examining the effects of bismuth in birds. Significant positive relationships between bismuth- and lead-tissue levels for muscle when all species were combined (and for B. canadensis and C. caerulescens separately) can be explained by noting that bismuth is a contaminant of lead. Thus, more research is recommended to confirm the appropriateness of bismuth as a 'nontoxic' shot alternative.

  4. Operating Practice for Recovering Bismuth from Bismuth Dross%从铋渣中回收铋的生产实践

    Institute of Scientific and Technical Information of China (English)

    刘金铭

    2015-01-01

    阐述了从处理铅阳极泥时产生的铋渣中回收铋的生产实践,采用湿法浸出→氯氧铋→热浓碱转型→氧化铋→还原熔炼→火法精炼的生产工艺,为铋渣的处理提供了新的途径。%This paper expounds operating practice for recovering bismuth from bismuth dross that were outputed during dealing with the lead anode mud in pyrometallurgical process,which uesd production process of leaching—bismuth oxychloride—transformation—bismuth oxide—reduction smelting—pyrometallurgical refining.The operating practice provided a new technology to process the bismuth dross.

  5. Testing of T91 steel in heavy liquid metals

    Science.gov (United States)

    Chocholoušek, M.; Fulín, Z.; Janoušek, J.; Špirit, Z.

    2017-02-01

    Tests of candidate construction materials for a heavy liquid metal environment are performed at Centrum Vyzkumu Rez. Tests are focused among other things on the influence of corrosive environments on the mechanical properties of T91 steel. Non-standard environments require special testing devices, which must be able to perform tests in liquid lead or liquid lead bismuth eutectic. An important issue is also the monitoring of the oxygen volume, which has an influence on the production and stability of oxide layers and therefore on crack initiation. This article presents the issue of testing steel T91 and the associated development of a testing device for slow strain rate tests, especially in liquid lead bismuth eutectic environment.

  6. Light Emitting Diodes (LEDs)

    Science.gov (United States)

    1997-01-01

    A special lighting technology was developed for space-based commercial plant growth research on NASA's Space Shuttle. Surgeons have used this technology to treat brain cancer on Earth, in two successful operations. The treatment technique, called Photodynamic Therapy, requires the surgeon to use tiny, pinhead-size Light Emitting Diodes (LEDs) (a source that releases long wavelengths of light ) to activate light-sensitive, tumor-treating drugs. 'A young woman operated on in May 1999 has fully recovered with no complications and no evidence of the tumor coming back,' said Dr. Harry Whelan, a pediatric neurologist at the Medical Hospital of Wisconsin in Milwaukee. Laser light has been used for this type of surgery in the past, but the LED light illuminates through all nearby tissues, reaching parts of a tumor that shorter wavelengths of laser light carnot. The new probe is safer because the longer wavelengths of light are cooler than the shorter wavelengths of laser light, making the LED less likely to injure normal brain tissue near the tumor. It can be used for hours at a time while still remaining cool to the touch. The LED light source is compact, about the size of a briefcase, and can be purchased for a fraction of the cost of a laser. The LEDs, developed and managed by NASA's Marshall Space Flight Center, have been used on seven Space Shuttle flights inside the Microgravity Astroculture Facility. This technology has also been successfully used to further commercial research in crop growth.

  7. Focused ion beam processing to fabricate ohmic contact electrodes on a bismuth nanowire for Hall measurements

    OpenAIRE

    Murata, Masayuki; Hasegawa, Yasuhiro

    2013-01-01

    Ohmic contact electrodes for four-wire resistance and Hall measurements were fabricated on an individual single-crystal bismuth nanowire encapsulated in a cylindrical quartz template. Focused ion beam processing was utilized to expose the side surfaces of the bismuth nanowire in the template, and carbon and tungsten electrodes were deposited on the bismuth nanowire in situ to achieve electrical contacts. The temperature dependence of the four-wire resistance was successfully measured for the ...

  8. Dielectric spectra of bismuth vanadate Bi4V2O11

    Energy Technology Data Exchange (ETDEWEB)

    Borisov, V.N.; Pashkov, V.M.; Poplavko, IU.M.; Avakian, P.B.; Osipian, V.G. (Kievskii Politekhnicheskii Institut, Kiev (Ukrainian SSR))

    1990-06-01

    Results of a study of the temperature-frequency dependence of the behavior of the dielectric parameters of bismuth vanadate, Bi4V2O11, in the frequency range 1-100 GHz are reported. It is shown that bismuth vanadate is characterized by a large number of phase transitions. Yet another, previously unknown, phase transition in bismuth vanadate, masked by a relaxation process, has been observed in the temperature range 410-420 K. 12 refs.

  9. Dielectric spectra of bismuth vanadate Bi4V2O11

    Science.gov (United States)

    Borisov, V. N.; Pashkov, V. M.; Poplavko, Iu. M.; Avakian, P. B.; Osipian, V. G.

    1990-06-01

    Results of a study of the temperature-frequency dependence of the behavior of the dielectric parameters of bismuth vanadate, Bi4V2O11, in the frequency range 1-100 GHz are reported. It is shown that bismuth vanadate is characterized by a large number of phase transitions. Yet another, previously unknown, phase transition in bismuth vanadate, masked by a relaxation process, has been observed in the temperature range 410-420 K.

  10. Standard triple, bismuth pectin quadruple and sequential therapies for Helicobacter pylori eradication

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    AIM: To compare the effectiveness of standard triple, bismuth pectin quadruple and sequential therapies for Helicobacter pylori (H. pylori ) eradication in a randomized, double-blinded, comparative clinical trial in China. METHODS: A total of 215 H. pylori -positive patients were enrolled in the study and randomly allocated into three groups: group A (n = 72) received a 10-d bismuth pectin quadruple therapy (20 mg rabeprazole bid , 1000 mg amoxicillin bid , 100 mg bismuth pectin qid , and 500 mg levofloxaci...

  11. Bismuth-induced Raman modes in GaP1- x Bi x

    Science.gov (United States)

    Christian, Theresa M.; Fluegel, Brian; Beaton, Daniel A.; Alberi, Kirstin; Mascarenhas, Angelo

    2016-10-01

    Dilute bismide semiconductor alloys are a promising material platform for optoelectronic devices due to drastic impacts of bismuth on the electronic structure of the alloy. At the same time, the details of bismuth incorporation in the lattice are not fully understood. In this work, we conduct Raman scattering spectroscopy on GaP1- x Bi x epilayers grown by molecular beam epitaxy (MBE) and identify several bismuth-related Raman features including gap vibration modes at 296, 303, and 314 cm-1. This study paves the way for more detailed analysis of the local symmetry at bismuth incorporation sites in the dilute bismide alloy regime.

  12. Nanophotonic Modulator with Bismuth Ferrite as Low-loss Switchable Material

    DEFF Research Database (Denmark)

    Babicheva, Viktoriia; Zhukovsky, Sergei; Lavrinenko, Andrei

    2015-01-01

    We propose a nanophotonic waveguide modulator with bismuth ferrite as a tunable material. Due to near-zero losses in bismuth ferrite, modulation with up to 20 dB/μm extinction ratio and 12 μm propagation length is achieved.......We propose a nanophotonic waveguide modulator with bismuth ferrite as a tunable material. Due to near-zero losses in bismuth ferrite, modulation with up to 20 dB/μm extinction ratio and 12 μm propagation length is achieved....

  13. Optimal biliary drainage for inoperable Klatskin's tumor based on Bismuth type

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To investigate differences in the effects of biliary drainage procedures in patients with inoperable Klatskin's tumor based on Bismuth type, considering endoscopic retrograde biliary drainage (ERBD), external percutaneous transhepatic biliary drainage (EPTBD) and internal biliary stenting via the PTBD tract (IPTBD).METHODS: The initial success rate, cumulative patency rate, and complication rate were compared retrospectively, according to the Bismuth type and ERBD,EPTBD, and IPTBD. Patency was defined as the duration for adequate initial bile drainage or to the point of the patient's death associated with inadequate drainage.RESULTS: One hundred thirty-four patients (93 men,41 women; 21 Bismuth type Ⅱ, 47 Ⅲ, 66 Ⅳ; 34 ERBD,66 EPTBD, 34 IPTBD) were recruited. There were no differences in demographics among the groups.Adequate initial relief of jaundice was achieved in 91% of patients without a significant difference in the results among different procedures or Bismuth types. The cumulative patency rates for ERBD and IPTBD were better than those for EPTBD with Bismuth type Ⅲ.IPTBD provided an excellent response for Bismuth type Ⅳ. However, there was no difference in the patency rate among drainage procedures for Bismuth type Ⅱ.Procedure-related cholangitis occurred less frequently with EPTBD than with ERBD and IPTBD.CONCLUSION: ERBD is recommended as the firstline drainage procedure for the palliation of jaundice in patients with inoperable Klatskin's tumor of Bismuth type Ⅱ or Ⅲ, but IPTBD is the best option for Bismuth type Ⅳ.

  14. Antibacterial effects of Bismuth compounds and it synergy with Tetracycline and Metronidazole on Helicobacter Pylori

    Directory of Open Access Journals (Sweden)

    Rajabie A

    1997-04-01

    Full Text Available Bismuth salts and different antimicrobials including Metonidazole & Tetracyclines were used in the assessment of inhibition zone of Helicobacter pylori cultures on solid media. Antibiotics were used or in combined in order to find out their possible synergistic effects. It was showed that: only Bismuth substrate and not then salts have antibacterial effects on Helicobacter pylori and also on the other bacteria such as staphylococci; salmonella and brulla. In addition, only Bismuth substrances showed remarkable synergistic effects with antimicrobial drugs against Helicobacter pylori. Therefore the data obtained from this investigation confirm previously known effect of combination antibiotic therapy including Bismuth compounds in eradicating Helicobacter pylori.

  15. Bismuth-Induced Raman Modes in GaP1-xBix

    Energy Technology Data Exchange (ETDEWEB)

    Christian, Theresa M.; Fluegel, Brian; Beaton, Daniel A.; Alberi, Kirstin; Mascarenhas, Angelo

    2016-10-01

    Dilute bismide semiconductor alloys are a promising material platform for optoelectronic devices due to drastic impacts of bismuth on the electronic structure of the alloy. At the same time, the details of bismuth incorporation in the lattice are not fully understood. In this work, we conduct Raman scattering spectroscopy on GaP1- x Bi x epilayers grown by molecular beam epitaxy (MBE) and identify several bismuth-related Raman features including gap vibration modes at 296, 303, and 314 cm-1. This study paves the way for more detailed analysis of the local symmetry at bismuth incorporation sites in the dilute bismide alloy regime.

  16. Preparation of high-purity bismuth by sulphur deleadization in vacuum distillation

    Institute of Scientific and Technical Information of China (English)

    熊利芝; 何则强; 刘文萍; 麻成金; 戴永年

    2004-01-01

    The feasibility of separation of impurities in refined bismuth and sulphur deleadization with vacuum distillation was studied theoretically. Experimental studies on sulphur deleadization were carried out under vacuum.The influences of amount of sulphur, distillation temperature, vacuum degree and distillation time on deleadization were investigated and an optimal technical condition was achieved. The content of lead in refined bismuth can be decreased from 30 μg/g to 0.21 μg/g, which has reached the level of "5N" high-purity bismuth. Other impurities in refined bismuth can be also removed effectively under certain conditions.

  17. Elimination of the beam effect on channeling dips of bismuth implanted in silicon

    Science.gov (United States)

    Wagh, A. G.; Radhakrishnan, S.; Gaonkar, S. G.; Kansara, M. J.

    1980-01-01

    The effect of the analysing He + ion beam has been eliminated from channeling measurements on Si(Bi) by extrapolating the plot of normalised yield against He + dose to zero ion dose. The magnitude of the beam effect varies with the angle of incidence, being minimum for beam incidence along the crystallographic axis. The axial channeling dips thus obtained exhibit similar minimum yields for bismuth and silicon. The bismuth dips are, however, narrower than for silicon. The planar channeling experiments, on the other hand, yield nearly identical bismuth and silicon dips. The results indicate that the bismuth atom occupies the substitutional site in silicon, but the lattice is strained in its vicinity.

  18. Colloidal bismuth subcitrate in non-ulcer dyspepsia.

    Directory of Open Access Journals (Sweden)

    Khanna M

    1992-07-01

    Full Text Available The effect of colloidal bismuth subcitrate (De-Nol on symptoms, Helicobacter pylori status and histological features was studied in 35 patients with non-ulcer dyspepsia. Pain (34 cases and gas bloat (18 were the predominant symptoms. H pylori was present in 26 (74.3% patients. Gastritis and duodenitis were present in 29 of 32 and 22 of 31 cases respectively in whom biopsies were available. Relief in symptoms after treatment was seen in 29 (82.8% cases. Improvement in gastritis and duodenitis was noted in 60.8% and 58.8% respectively; over 70% of H pylori positive patients cleared the organism. These changes did not correlate with the relief in symptoms. We conclude that colloidal bismuth subcitrate is effective in the short term treatment of non-ulcer dyspepsia. It also clears H pylori infection and results in improvement of histological features.

  19. Large area bismuth absorbers for X-ray microcalorimeters

    Energy Technology Data Exchange (ETDEWEB)

    Vaillancourt, J.E. E-mail: vaillancourt@wisp.physics.wisc.edu; Allen, C.A.; Brekosky, R.; Dosaj, A.; Galeazzi, M.; Kelley, R.; Liu, D.; McCammon, D.; Porter, F.S.; Rocks, L.E.; Sanders, W.T.; Stahle, C.K

    2004-03-11

    Two challenges facing the use of large area (2 mmx2 mm) bismuth absorbers for microcalorimetry are uncertainties in the heat capacity of bismuth and the effects of lateral heat conduction and position dependence due to the absorber's large size. We have measured the heat capacity of three Bi samples to be 0.3-0.6 J K{sup -1} m{sup -3} at 100 mK. These absorbers also exhibit response variations as phonons created by an X-ray event at an absorber edge will take longer to propagate to the thermometer attachment point than those at the absorber center. This effect may degrade the detector's energy resolution if the propagation time is not very short compared to the thermometer time constant. We show that the response of the largest absorber varies by {approx}4% across its area.

  20. Bismuth Telluride and Its Alloys as Materials for Thermoelectric Generation

    Directory of Open Access Journals (Sweden)

    H. Julian Goldsmid

    2014-03-01

    Full Text Available Bismuth telluride and its alloys are widely used as materials for thermoelectric refrigeration. They are also the best materials for use in thermoelectric generators when the temperature of the heat source is moderate. The dimensionless figure of merit, ZT, usually rises with temperature, as long as there is only one type of charge carrier. Eventually, though, minority carrier conduction becomes significant and ZT decreases above a certain temperature. There is also the possibility of chemical decomposition due to the vaporization of tellurium. Here we discuss the likely temperature dependence of the thermoelectric parameters and the means by which the composition may be optimized for applications above room temperature. The results of these theoretical predictions are compared with the observed properties of bismuth telluride-based thermoelements at elevated temperatures. Compositional changes are suggested for materials that are destined for generator modules.

  1. Lead-bismuth eutectic recrystallization studies for the Megapie target

    Energy Technology Data Exchange (ETDEWEB)

    Zucchini, A. [ENEA, FIS/MET, Centro Ricerche ' E.Clementel' , via Don Fiammelli 2, 40128 Bologna (Italy); Agostini, P. [ENEA, FIS/ING, Centro Ricerche Brasimone, 40032 Camugnano, Bologna (Italy); Baicchi, E. [ENEA, FIS/ING, Centro Ricerche Brasimone, 40032 Camugnano (Bologna) (Italy)]. E-mail: elio.baicchi@brasimone.enea.it

    2005-02-01

    The expansion behaviour after freezing of the lead-bismuth eutectic (LBE) with 44.5% lead and 55.5% bismuth is described according to the reported theory. The issue of the vessel structural integrity after LBE recrystallization was dealt with by experimental and numerical studies performed in the frame of the Megapie (Megawatt Pilot Experiment) project. We have identified the important elements which, in the case of LBE solidification inside the Megapie target, play a role in the reduction of the possible vessel over-stressing; among them, the LBE yield strength has been tested under significant experimental conditions. The resulting suggestions can also be related to the design and to the freezing procedures for other LBE technology facilities.

  2. Ab initio electronic structure and optical conductivity of bismuth tellurohalides

    CERN Document Server

    Schwalbe, Sebastian; Starke, Ronald; Schober, Giulio A H; Kortus, Jens

    2016-01-01

    We investigate the electronic structure, dielectric and optical properties of bismuth tellurohalides BiTeX (X = I, Cl, Br) by means of all-electron density functional theory. In particular, we present the ab initio conductivities and dielectric tensors calculated over a wide frequency range, and compare our results with the recent measurements by Akrap et al. , Makhnev et al. , and Rusinov et al. . We show how the low-frequency branch of the optical conductivity can be used to identify characteristic intra- and interband transitions between the Rashba spin-split bands in all three bismuth tellurohalides. We further calculate the refractive indices and dielectric constants, which in turn are systematically compared to previous predictions and measurements. We expect that our quantitative analysis will contribute to the general assessment of bulk Rashba materials for their potential use in spintronics devices.

  3. Physical properties of heavy liquid-metal coolants in a wide temperature range

    Directory of Open Access Journals (Sweden)

    Borisenko A.

    2011-05-01

    Full Text Available The pulse-phase method, the gamma-attenuation method and the method of dumping oscillation of a crucible with a melt were used for measuring the velocity of sound, the density and the kinematic viscosity of a set of liquid-metal coolants for perspective nuclear reactors. There are liquid gallium, indium, tin, lead, bismuth and lead-bismuth eutectic alloy among the melts investigated. The accuracy of the measurements was as high as 0.3%, 0.2 to 0.4% and 1.5% for the ultrasound velocity, the density and the viscosity, correspondingly.

  4. The re-crystallization issue in lead-bismuth technology

    Energy Technology Data Exchange (ETDEWEB)

    Agostini, P. [ENEA C.R. Brasimone, 40032 Camugnano, Bologna (Italy); Baicchi, E. [ENEA C.R. Brasimone, 40032 Camugnano, Bologna (Italy)]. E-mail: elio.baicchi@brasimone.enea.it; Zucchini, A. [ENEA C.R. Brasimone, 40032 Camugnano, Bologna (Italy); Benamati, G. [ENEA C.R. Brasimone, 40032 Camugnano, Bologna (Italy)

    2004-11-01

    Numerical and experimental studies were performed to investigate the behaviour of lead-bismuth eutectic (LBE) after solidification. Re-crystallization of LBE is the main phenomenon to consider; it may lead to serious over-stressing of structural materials. The conditions for the target vessel of MEGAwatt PIlot Experiment (MEGAPIE) were especially considered. Some general recommendations were deduced in order to help avoiding dangerous events.

  5. Low temperature Hall effect in bismuth chalcogenides thin films

    OpenAIRE

    Kuntsevich, A. Yu.; Gabdullin, A. A.; Prudkogliad, V. A.; Selivanov, Yu. G.; Chizhevskii, E. G.; Pudalov, V. M.

    2016-01-01

    Bismuth chalcogenides are the most studied 3D topological insulators. As a rule, at low temperatures thin films of these materials demonstrate positive magnetoresistance due to weak antilocalization. Weak antilocalization should lead to resistivity decrease at low temperatures; in experiments, however, resistivity grows as temperature decreases. From transport measurements for several thin films (with various carrier density, thickness, and carrier mobility), and by using purely phenomenologi...

  6. Resistivity and Seebeck coefficient measurements of a bismuth microwire array

    Energy Technology Data Exchange (ETDEWEB)

    Ishikawa, Y. [Graduate School of Science and Engineering, Saitama University, 338-8570 (Japan)]. E-mail: ishikawa@kan.env.gse.saitama-u.ac.jp; Hasegawa, Y. [Graduate School of Science and Engineering, Saitama University, 338-8570 (Japan); Morita, H. [Saitama Industrial Technology Center, Saitama Prefecture, 333-0844 (Japan); Kurokouchi, A. [Saitama Industrial Technology Center, Saitama Prefecture, 333-0844 (Japan); Wada, K. [Saitama Industrial Technology Center, Saitama Prefecture, 333-0844 (Japan); Komine, T. [Department of Media and Telecommunications Engineering, Ibaraki University, 316-8511 (Japan); Nakamura, H. [National Institute for Fusion Science, 322-6 Oroshi-cho, Toki, Gifu 509-5252 (Japan)

    2005-11-01

    The resistivity and Seebeck coefficient of a bismuth microwire array (wire diameter: 25 {mu}m) were successfully measured from 25 to 300 K. To eliminate the influence of the contact resistance between the wire edges of the microwire array and copper electrodes, the titanium (100 nm)/copper (500 nm) film layers were deposited as interlayer on the wire edge by ion plating method. Copper electrodes were glued by using Pb-Sn solder. The resistivity and the Seebeck coefficient at 300 K were approximately 1.8x10{sup -6} {omega}m and -54x10{sup -6} V/K, respectively. The value of the resistivity and the Seebeck coefficient were in good agreement with those of bulk polycrystalline bismuth reported previously. Thus, the effects of the contact resistance for the microwire array were almost resolved, and the chemical reaction of the Pb-Sn solder and bismuth was prevented by using the thin-film layer. The technique is expected to be applicable to nanowire arrays as well.

  7. Bismuth pyrochlore-based thin films for dielectric energy storage

    Science.gov (United States)

    Michael, Elizabeth K.

    The drive towards the miniaturization of electronic devices has created a need for dielectric materials with large energy storage densities. These materials, which are used in capacitors, are a critical component in many electrical systems. Here, the development of dielectric energy storage materials for pulsed power applications, which require materials with the ability to accumulate a large amount of energy and then deliver it to the system rapidly, is explored. The amount of electrostatic energy that can be stored by a material is a function of the induced polarization and the dielectric breakdown strength of the material. An ideal energy storage dielectric would possess a high relative permittivity, high dielectric breakdown strength, and low loss tangent under high applied electric fields. The bismuth pyrochlores are a compositionally tunable family of materials that meet these requirements. Thin films of cubic pyrochlore bismuth zinc niobate, bismuth zinc tantalate, and bismuth zinc niobate tantalate, were fabricated using a novel solution chemistry based upon the Pechini method. This solution preparation is advantageous because it avoids the use of teratogenic solvents, such as 2-methoxyethanol. Crystalline films fabricated using this solution chemistry had very small grains that were approximately 27 nm in lateral size and 35 nm through the film thickness. Impedance measurements found that the resistivity of the grain boundaries was two orders of magnitude higher than the resistivity of the grain interior. The presence of many resistive grain boundaries impeded conduction through the films, resulting in high breakdown strengths for these materials. In addition to high breakdown strengths, this family of materials exhibited moderate relative permittivities of between 55 +/- 2 and 145 +/- 5, for bismuth zinc tantalate and bismuth zinc niobate, respectively, and low loss tangents on the order of 0.0008 +/- 0.0001. Increases in the concentration of the tantalum

  8. Atomic Layer Deposition of Bismuth Vanadates for Solar Energy Materials.

    Science.gov (United States)

    Stefik, Morgan

    2016-07-07

    The fabrication of porous nanocomposites is key to the advancement of energy conversion and storage devices that interface with electrolytes. Bismuth vanadate, BiVO4 , is a promising oxide for solar water splitting where the controlled fabrication of BiVO4 layers within porous, conducting scaffolds has remained a challenge. Here, the atomic layer deposition of bismuth vanadates is reported from BiPh3 , vanadium(V) oxytriisopropoxide, and water. The resulting films have tunable stoichiometry and may be crystallized to form the photoactive scheelite structure of BiVO4 . A selective etching process was used with vanadium-rich depositions to enable the synthesis of phase-pure BiVO4 after spinodal decomposition. BiVO4 thin films were measured for photoelectrochemical performance under AM 1.5 illumination. The average photocurrents were 1.17 mA cm(-2) at 1.23 V versus the reversible hydrogen electrode using a hole-scavenging sulfite electrolyte. The capability to deposit conformal bismuth vanadates will enable a new generation of nanocomposite architectures for solar water splitting.

  9. Aerosol deposition of (Cu,Ti) substituted bismuth vanadate films

    Energy Technology Data Exchange (ETDEWEB)

    Exner, Jörg, E-mail: Functional.Materials@Uni-Bayreuth.de [University of Bayreuth, Department of Functional Materials, Universitätsstraße 30, 95440 Bayreuth (Germany); Fuierer, Paul [Materials and Metallurgical Engineering Department, New Mexico Institute of Mining and Technology, Socorro, NM 87801 (United States); Moos, Ralf [University of Bayreuth, Department of Functional Materials, Universitätsstraße 30, 95440 Bayreuth (Germany)

    2014-12-31

    Bismuth vanadate, Bi{sub 4}V{sub 2}O{sub 11}, and related compounds with various metal (Me) substitutions, Bi{sub 4}(Me{sub x}V{sub 1−x}){sub 2}O{sub 11−δ}, show some of the highest ionic conductivities among the known solid oxide electrolytes. Films of Cu and Ti substituted bismuth vanadate were prepared by an aerosol deposition method, a spray coating process also described as room temperature impact consolidation. Resultant films, several microns in thickness, were dense with good adhesion to the substrate. Scanning electron microscopy and high temperature X-ray diffraction were used to monitor the effects of temperature on the structure and microstructure of the film. The particle size remained nano-scale while microstrain decreased rapidly up to 500 °C, above which coarsening and texturing increased rapidly. Impedance measurements of films deposited on inter-digital electrodes revealed an annealing effect on the ionic conductivity, with the conductivity exceeding that of a screen printed film, and approaching that of bulk ceramic. - Highlights: • Cu and Ti doped bismuth vanadate films were prepared by aerosol deposition (AD). • Dense 3–5 μm thick films were deposited on alumina, silicon and gold electrodes. • Annealing of the AD-layer increases the conductivity by 1.5 orders of magnitude. • Effect of temperature on structure and microstructure was investigated.

  10. Dense superconducting phases of copper-bismuth at high pressure

    Science.gov (United States)

    Amsler, Maximilian; Wolverton, Chris

    2017-08-01

    Although copper and bismuth do not form any compounds at ambient conditions, two intermetallics, CuBi and Cu11Bi7 , were recently synthesized at high pressures. Here we report on the discovery of additional copper-bismuth phases at elevated pressures with high densities from ab initio calculations. In particular, a Cu2Bi compound is found to be thermodynamically stable at pressures above 59 GPa, crystallizing in the cubic Laves structure. In strong contrast to Cu11Bi7 and CuBi, cubic Cu2Bi does not exhibit any voids or channels. Since the bismuth lone pairs in cubic Cu2Bi are stereochemically inactive, the constituent elements can be closely packed and a high density of 10.52 g/cm3 at 0 GPa is achieved. The moderate electron-phonon coupling of λ =0.68 leads to a superconducting temperature of 2 K, which exceeds the values observed both in Cu11Bi7 and CuBi, as well as in elemental Cu and Bi.

  11. Study of barium bismuth titanate prepared by mechanochemical synthesis

    Directory of Open Access Journals (Sweden)

    Lazarević Z.Ž.

    2009-01-01

    Full Text Available Barium-bismuth titanate, BaBi4Ti4O15 (BBT, a member of Aurivillius bismuth-based layer-structure perovskites, was prepared from stoichiometric amounts of barium titanate and bismuth titanate obtained via mechanochemical synthesis. Mechanochemical synthesis was performed in air atmosphere in a planetary ball mill. The reaction mechanism of BaBi4Ti4O15 and the preparation and characteristics of BBT ceramic powders were studied using XRD, Raman spectroscopy, particle analysis and SEM. The Bi-layered perovskite structure of BaBi4Ti4O15 ceramic forms at 1100 °C for 4 h without a pre-calcination step. The microstructure of BaBi4Ti4O15 exhibits plate-like grains typical for the Bi-layered structured material and spherical and polygonal grains. The Ba2+ addition leads to changes in the microstructure development, particularly in the change of the average grain size.

  12. Solvothermal synthesis and study of nonlinear optical properties of nanocrystalline thallium doped bismuth telluride

    Energy Technology Data Exchange (ETDEWEB)

    Molli, Muralikrishna, E-mail: muralikrishnamolli@sssihl.edu.in [Department of Physics, Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam-515 134 (India); Parola, Sowmendran; Avinash Chunduri, L.A.; Aditha, Saikiran; Sai Muthukumar, V; Mimani Rattan, Tanu; Kamisetti, Venkataramaniah [Department of Physics, Sri Sathya Sai Institute of Higher Learning, Prasanthinilayam-515 134 (India)

    2012-05-15

    Nanocrystalline Bismuth telluride and thallium (4 mol %) doped Bismuth telluride were synthesized through hydrothermal method. The as-prepared products were characterized using Powder X-ray Diffraction, High Resolution Transmission Electron Microscopy, Energy Dispersive X-Ray Spectroscopy, UV-Visible spectroscopy and Fourier Transform Infrared Spectroscopy. Powder XRD results revealed the crystalline nature of the obtained phases. HRTEM showed the particle-like morphology of the products. The decrease in the absorption coefficient due to thallium doping was observed in FTIR spectra. The intensity dependent nonlinear optical properties of nanocrystalline bismuth telluride and thallium doped bismuth telluride were studied using the Z-scan technique in open-aperture configuration. Bismuth telluride doped with thallium showed enhanced nonlinear optical response compared to pristine bismuth telluride and hence could be used as a potential candidate for optical power limiting applications. - Graphical Abstract: Nonlinear transmission (Z-scan) curves of nanocrystalline bismuth telluride ({Delta}) and thallium doped bismuth telluride ({open_square}). Thallium doped bismuth telluride showed enhanced nonlinear absorption compared to bismuth telluride. Inset: TEM micrograph of bismuth telluride nanocrystallites. Highlights: Black-Right-Pointing-Pointer Synthesis of Nanocrystalline Bi{sub 2}Te{sub 3} and Thallium doped Bi{sub 2}Te{sub 3} through solvothermal method. Black-Right-Pointing-Pointer Reduced absorption coefficient due to thallium doping found from IR spectroscopy. Black-Right-Pointing-Pointer Open-aperture Z-scan technique for nonlinear optical studies. Black-Right-Pointing-Pointer Two photon absorption based model for theoretical fitting of Z-scan data. Black-Right-Pointing-Pointer Enhanced nonlinear absorption in Thallium doped Bi{sub 2}Te{sub 3} - potential candidate for optical power limiting applications.

  13. Emissive Ion Thruster -EMIT Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A propulsion system is proposed that is based on acceleration of ions emitted from a thin, solid-state electrochemical ceramic membrane. This technology would...

  14. Vibration Monitoring Using Fiber Optic Sensors in a Lead-Bismuth Eutectic Cooled Nuclear Fuel Assembly †

    Science.gov (United States)

    De Pauw, Ben; Lamberti, Alfredo; Ertveldt, Julien; Rezayat, Ali; van Tichelen, Katrien; Vanlanduit, Steve; Berghmans, Francis

    2016-01-01

    Excessive fuel assembly vibrations in nuclear reactor cores should be avoided in order not to compromise the lifetime of the assembly and in order to prevent the occurrence of safety hazards. This issue is particularly relevant to new reactor designs that use liquid metal coolants, such as, for example, a molten lead-bismuth eutectic. The flow of molten heavy metal around and through the fuel assembly may cause the latter to vibrate and hence suffer degradation as a result of, for example, fretting wear or mechanical fatigue. In this paper, we demonstrate the use of optical fiber sensors to measure the fuel assembly vibration in a lead-bismuth eutectic cooled installation which can be used as input to assess vibration-related safety hazards. We show that the vibration characteristics of the fuel pins in the fuel assembly can be experimentally determined with minimal intrusiveness and with high precision owing to the small dimensions and properties of the sensors. In particular, we were able to record local strain level differences of about 0.2 μϵ allowing us to reliably estimate the vibration amplitudes and modal parameters of the fuel assembly based on optical fiber sensor readings during different stages of the operation of the facility, including the onset of the coolant circulation and steady-state operation. PMID:27110782

  15. 液体吸收法脱除涂料生产中排放有机废气的研究%Study on the Removal of Organic Waste Gas Emitted from the Coatings Production by the Liquid Absorption Method

    Institute of Scientific and Technical Information of China (English)

    王立新; 刘松洁; 李守光

    2015-01-01

    According to the characteristics of organic waste gas content emitted from the production of solvent based coatings,six organic solvents and their mixture were selected to simulate organic waste gas. The absorption properties of absorbing solution for the simulated organic waste gas were systematically evaluated by two parameters of saturated absorption and average absorption rate. The test results showed that the order of absorption properties of 10th mineral oil was in the sequence of xylene>butyl acetate>mixture waste gas >cyclohexanone>PMA>S-100 solvent oil>ethyl acetate. There was little effect of viscosity on the absorption properties and also showed that greater viscosity,worse absorption properties. The absorption properties of biodiesel was better than that of mineral oil.%根据溶剂型涂料生产排放的有机废气含量的特点,分别选择了6种有机溶剂及其混合物模拟有机废气,通过饱和吸收量和平均吸收速率两项参数,系统评定了吸收液对有机废气的吸收性能.试验结果表明:10#白油对这些有机废气的吸收性能次序为:二甲苯>乙酸丁酯>混合废气>环己酮>丙二醇甲醚醋酸酯(PMA)>S-100溶剂油>乙酸乙酯;白油黏度对混合废气的吸收性能影响较小,但是表现为黏度越大,吸收性能越差;生物柴油吸收混合废气的性能优于白油.

  16. Local Structural Distortion Induced Uniaxial Negative Thermal Expansion in Nanosized Semimetal Bismuth.

    Science.gov (United States)

    Li, Qiang; Zhu, He; Zheng, Lirong; Fan, Longlong; Ren, Yang; Chen, Jun; Deng, Jinxia; Xing, Xianran

    2016-11-01

    The corrugated layer structure bismuth has been successfully tailored into negative thermal expansion along c axis by size effect. Pair distribution function and extended X-ray absorption fine structure are combined to reveal the local structural distortion for nanosized bismuth. The comprehensive method to identify the local structure of nanomaterials can benefit the regulating and controlling of thermal expansion in nanodivices.

  17. Effect of O-vacancies on magnetic properties of bismuth ferrite nanoparticles by solution evaporation method

    Energy Technology Data Exchange (ETDEWEB)

    Afzal, A.M., E-mail: Amirafzal461@gmail.com [Department of Physics, GC University, Faisalabad 38000 (Pakistan); Umair, M., E-mail: umairranwerr@gmail.com [Department of Physics, GC University, Faisalabad 38000 (Pakistan); Dastgeer, G., E-mail: dtedastgeer@gmail.com [Department of Physics, University of Agriculture, Faisalabad 38000 (Pakistan); Rizwan, M., E-mail: h.rizwan70@gmail.com [Department of Physics, GC University, Faisalabad 38000 (Pakistan); Yaqoob, M.Z., E-mail: zeeshaan32@gmail.com [Department of Physics, GC University, Faisalabad 38000 (Pakistan); Rashid, R., E-mail: rashid.kanwar22@gmail.com [Department of Physics, University of Agriculture, Faisalabad 38000 (Pakistan); Munir, H.S., E-mail: sadiamunir.cute@gmail.com [Department of Physics, GC University, Faisalabad 38000 (Pakistan)

    2016-02-01

    Bismuth ferrite is a multiferroic material which shows high magnetization and polarization at room temperature. In present work, the effect of Oxygen (O) vacancies on magnetic properties of bismuth ferrite nanoparticles is studied. Bismuth ferrite nanoparticles (BiFeO{sub 3}) were synthesized by solution evaporation method (SEM) at room temperature. The sample was annealed under two different atmospheres such as in air and oxygen, to check the effect of O-vacancies on magnetic properties. The average crystallite size of Bismuth ferrite nanoparticles (NPs) as calculated by X-ray diffraction (XRD) falls in the range of 23–32 nm and 26–39 nm for the case of air and oxygen respectively. The crystallite size of bismuth ferrite nanoparticles increases as the temperature was varied from 450 °C to 650 °C. Further the influence of annealing temperature on the magnetic properties of the bismuth ferrite nanoparticles was also observed. It was concluded that the magnetic properties of Bismuth ferrite nanoparticles are directly interconnected to annealing atmosphere and annealing temperature. The magnetic properties were increased in the case of oxygen annealing, which actually leads in our case to an improvement of the crystallinity. - Highlights: • Bismuth ferrite was synthesized by solution evaporation method. • The effect of different annealing atmosphere on magnetic properties was studied. • The magnetic properties dramatically increased in case of Oxygen annealing. • The influence of crystalline size on magnetic properties was studied. • The magnetization was decreased as the temperature and crystallite size increased.

  18. Terahertz lasing from silicon by infrared Raman scattering on bismuth centers

    NARCIS (Netherlands)

    Pavlov, S. G.; Bottger, U.; Eichholz, R.; Abrosimov, N. V.; Riemann, H.; Shastin, V. N.; Redlich, B.; Hubers, H. W.

    2009-01-01

    Stimulated emission at terahertz frequencies (4.5-5.8 THz) has been realized by electronic Raman scattering of infrared radiation on bismuth donor centers in silicon at low temperatures. The Stokes shift of the observed laser emission is 40.53 meV which corresponds to the bismuth intracenter transit

  19. Electronic Properties of Tin and Bismuth from Angular Correlation of Annihilation Photons

    DEFF Research Database (Denmark)

    Mogensen, O.E.; Trumpy, Georg

    1969-01-01

    ) deformed bismuth. For both metals, the single-crystal angular-correlation curves lie near to the free-electron parabola. The tin curves show more anisotropy than the bismuth curves. An important result is the clear anisotropy found in the high-momentum part of the curves—the tails—for both metals. Little...

  20. Effects of In Vitro Antibiotic Resistance on Treatment: Bismuth-Containing Regimens

    Directory of Open Access Journals (Sweden)

    Naoki Chiba

    2000-01-01

    Full Text Available Bismuth compounds remain useful for Helicobacter pylori eradication therapy. These include colloidal bismuth subcitrate (CBS, bismuth subsalicylate (BSS and, most recently, ranitidine bismuth citrate (RBC. CBS appears to prevent the development of imidazole resistance when coadministered with nitroimidazoles. Traditional triple therapy with bismuth, metronidazole and tetracycline or amoxicillin (BMT/A only partially overcomes metronidazole resistance. However, the addition of a PPI to bismuth triple therapy largely overcomes established metronidazole resistance if treatment is given for at least one week or more. When RBC rather than PPI is used with clarithromycin, this dual regimen appears to be more effective in preventing the development of secondary clarithromycin resistance. The triple combination of RBC, metronidazole and clarithromycin appears to be effective against metronidazole resistant strains of H pylori. Thus, overall, there is some evidence that bismuth compounds may prevent the development of antibiotic resistance and that existing antibiotic resistance may at least be partially overcome in vitro and in vivo. With the growing emergence of H pylori resistance to metronidazole and clarithromycin, further research to clarify the role of bismuth compounds is required.

  1. Method of Creating Micro-scale Silver Telluride Grains Covered with Bismuth Nanoparticles

    Science.gov (United States)

    Kim, Hyun-Jung (Inventor); Choi, Sang Hyouk (Inventor); King, Glen C. (Inventor); Park, Yeonjoon (Inventor); Lee, Kunik (Inventor)

    2014-01-01

    Provided is a method of enhancing thermoelectric performance by surrounding crystalline semiconductors with nanoparticles by contacting a bismuth telluride material with a silver salt under a substantially inert atmosphere and a temperature approximately near the silver salt decomposition temperature; and recovering a metallic bismuth decorated material comprising silver telluride crystal grains.

  2. Selective oxidation of propylene to acrolein by silica-supported bismuth molybdate catalysts

    DEFF Research Database (Denmark)

    Duc, Duc Truong; Ha, Hanh Nguyen; Fehrmann, Rasmus

    2011-01-01

    Silica-supported bismuth molybdate catalysts have been prepared by impregnation, structurally characterized and examined as improved catalysts for the selective oxidation of propylene to acrolein. Catalysts with a wide range of loadings (from 10 to 90 wt%) of beta bismuth molybdate (β-Bi2Mo2O9...

  3. Bismuth doping effect on crystal structure and photodegradation activity of Bi-TiO2 nanoparticles

    Science.gov (United States)

    Wu, Ming-Chung; Chang, Yin-Hsuan; Lin, Ting-Han

    2017-04-01

    The bismuth precursor is adopted as dopant to synthesize bismuth doped titanium dioxide nanoparticles (Bi-TiO2 NPs) with sol-gel method following by the thermal annealing treatment. We systematically developed a series of Bi-TiO2 NPs at several calcination temperatures and discovered the corresponding crystal structure by varying the bismuth doping concentration. At a certain 650 °C calcination temperature, the crystal structure of bismuth titanate (Bi2Ti2O7) is formed when the bismuth doping concentration is as high as 10.0 mol %. The photocatalytic activity of Bi-TiO2 NPs is increased by varying the doping concentration at the particular calcination temperature. By the definition X-ray diffraction (XRD) structural identification, a phase diagram of Bi-TiO2 NPs in doping concentration versus calcination temperature is provided. It can be useful for further study in the crystal structure engineering and the development of photocatalyst.

  4. An atomic absorption spectrometric method for the determination of phosphorus in foodstuffs using the bismuth phosphomolybdate complex

    Directory of Open Access Journals (Sweden)

    LJILJANA V. MIHAJLOVIC

    2000-06-01

    Full Text Available A new indirect AAS method using the bismuth phosphomolybdate complex for the determination of phosphorus in foodstuffs is suggested. The bismuth phosphomolybdate complex in acid medium was extacted with isobutyl methylketone and the phosphorus was determined through bismuth in an air/acetylene flame by utilising the 223.06 nm resonance line of bismuth. The interference caused by antimony and titanium can be neglected in the presence of excess of bismuth. The detection limit of the method is 0.008 mg/mL of phosphorus.

  5. Yttrium bismuth titanate pyrochlore mixed oxides for photocatalytic hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Merka, Oliver

    2012-10-18

    In this work, the sol-gel synthesis of new non-stoichiometric pyrochlore titanates and their application in photocatalytic hydrogen production is reported. Visible light response is achieved by introducing bismuth on the A site or by doping the B site by transition metal cations featuring partially filled d orbitals. This work clearly focusses on atomic scale structural changes induced by the systematical introduction of non-stoichiometry in pyrochlore mixed oxides and the resulting influence on the activity in photocatalytic hydrogen production. The materials were characterized in detail regarding their optical properties and their atomic structure. The pyrochlore structure tolerates tremendous stoichiometry variations. The non-stoichiometry in A{sub 2}O{sub 3} rich compositions is compensated by distortions in the cationic sub-lattice for the smaller Y{sup 3+} cation and by evolution of a secondary phase for the larger Bi{sup 3+} cation on the A site. For TiO{sub 2} rich compositions, the non-stoichiometry leads to a special vacancy formation in the A and optionally O' sites. It is shown that pyrochlore mixed oxides in the yttrium bismuth titanate system represent very active and promising materials for photocatalytic hydrogen production, if precisely and carefully tuned. Whereas Y{sub 2}Ti{sub 2}O{sub 7} yields stable hydrogen production rates over time, the bismuth richer compounds of YBiTi{sub 2}O{sub 7} and Bi{sub 2}Ti{sub 2}O{sub 7} are found to be not stable under irradiation. This drawback is overcome by applying a special co-catalyst system consisting of a precious metal core and a Cr{sub 2}O{sub 3} shell on the photocatalysts.

  6. Conduction mechanism in bismuth silicate glasses containing titanium

    Science.gov (United States)

    Dult, Meenakshi; Kundu, R. S.; Murugavel, S.; Punia, R.; Kishore, N.

    2014-11-01

    Bismuth silicate glasses mixed with different concentrations of titanium dioxide having compositions xTiO2-(60-x)Bi2O3-40SiO2 with x=0, 5, 10, 15 and 20 were prepared by the normal melt quench technique. The frequency dependence of the ac electrical conductivity of different compositions of titanium bismuth silicate glasses has been studied in the frequency range 10-1 Hz to 10 MHz and in the temperature range 623-703 K. The temperature and frequency dependent conductivity is found to obey Jonscher's universal power law for all the compositions of titanium bismuth silicate glass system. The dc conductivity (σdc), so called crossover frequency (ωH), and frequency exponent (s) have been estimated from the fitting of experimental data of ac conductivity with Jonscher's universal power law. Enthalpy to dissociate the cation from its original site next to a charge compensating center (Hf) and enthalpy of migration (Hm) have also been estimated. The conductivity data have been analyzed in terms of different theoretical models to determine the possible conduction mechanism. Analysis of the conductivity data and the frequency exponent shows that the correlated barrier hopping of electrons between Ti3+ and Ti4+ ions in the glasses is the most favorable mechanism for ac conduction. The temperature dependent dc conductivity has been analyzed in the framework of theoretical variable range hopping model (VRH) proposed by Mott which describe the hopping conduction in disordered semiconducting systems. The various polaron hopping parameters have also been deduced. Mott's VRH model is found to be in good agreement with experimental data and the values of inverse localization length of s-like wave function (α) obtained by this model with modifications suggested by Punia et al. are close to the ones reported for a number of oxide glasses.

  7. Cytotoxic Effect of Lipophilic Bismuth Dimercaptopropanol Nanoparticles on Epithelial Cells.

    Science.gov (United States)

    Rene, Hernandez-Delgadillo; Badireddy, Appala Raju; José, Martínez-Sanmiguel Juan; Francisco, Contreras-Cordero Juan; Israel, Martinez-Gonzalez Gustavo; Isela, Sánchez-Nájera Rosa; Chellam, Shankararaman; Claudio, Cabral-Romero

    2016-01-01

    Bismuth nanoparticles have many interesting properties to be applied in biomedical and medicinal sectors, however their safety in humans have not been comprehensively investigated. The objective of this research was to determine the cytotoxic effect of bismuth dimercaptopropanol nanoparticles (BisBAL NPs) on epithelial cells. The nanoparticles are composed of 18.7 nm crystallites on average and have a rhombohedral structure, agglomerating into chains-like or clusters of small nanoparticles. Based on MTT viability assay and fluorescence microscopy, cytotoxicity was not observed on monkey kidney cells after growing with 5 µM of BisBAL NPs for 24 h. Employing same techniques, identical results were obtained with human epithelial cells (HeLa), showing a not strain-dependent phenomenon. The absence of toxic effects on epithelial cells growing with BisBAL NPs was corroborated with long-time experiments (24-72 hrs.), showing no difference in comparison with growing control (cells without nanoparticles). Further, genotoxicity assays, comet assay and fluorescent microscopy and electrophoresis in bromide-stained agarose gel revealed no damage to genomic DNA of MA104 cells after 24 h. of exposition to BisBAL NPs. Finally, the effect of bismuth nanoparticles on protein synthesis was studied in cells growing with BisBAL NPs for 24 h. SDS-PAGE assays showed no difference between treated and untreated cells, suggesting that BisBAL NPs did not interfere with protein synthesis. Hence BisBAL NPs do not appear to exert cytotoxic effects suggesting their biological compatibility with epithelial cells.

  8. ORGANIC LIGHT EMITTING DIODE (OLED

    Directory of Open Access Journals (Sweden)

    Aririguzo Marvis Ijeaku

    2015-09-01

    Full Text Available An Organic Light Emitting Diode (OLED is a device composed of an organic layer that emits lights in response to an electrical current. Organic light emitting diodes have advanced tremendously over the past decades. The different manufacturing processes of the OLED itself to several advantages over flat panel displays made with LCD technology which includes its light weight and flexible plastic substrates, wider viewing angles, improved brightness, better power efficiency and quicker response time. However, its drawbacks include shorter life span, poor color balance, poor outdoor performance, susceptibility to water damage etc.The application of OLEDs in electronics is on the increase on daily basics from cameras to cell phones to OLED televisions, etc. Although OLEDs provides prospects for thinner, smarter, lighter and ultraflexible electronics displays, however, due to high cost of manufacturing, it is not yet widely used.

  9. Kinetics of Propagating Phase Transformation in Compressed Bismuth

    Energy Technology Data Exchange (ETDEWEB)

    Bastea, M; Bastea, S; Emig, J; Springer, P; Reisman, D

    2004-08-18

    The authors observed dynamically driven phase transitions in isentropically compressed bismuth. By changing the stress loading conditions they explored two distinct cases one in which the experimental signature of the phase transformation corresponds to phase-boundary crossings initiated at both sample interfaces, and another in which the experimental trace is due to a single advancing transformation front in the bulk of the material. They introduce a coupled kinetics-hydrodynamics model that for this second case enables them, under suitable simplifying assumptions, to directly extract characteristic transition times from the experimental measurements.

  10. Solution combustion synthesis and characterization of nanosized bismuth ferrite

    Science.gov (United States)

    Sai Kumar, V. Sesha; Rao, K. Venkateswara; Krishnaveni, T.; Kishore Goud, A. Shiva; Reddy, P. Ranjith

    2012-06-01

    The present paper describes a simple method of nanosized BiFeO3 by the solution combustion synthesis using bismuth and iron nitrates as oxidizers and the combination fuel of citric acid and ammonium hydroxide, with fuel to oxidizer ratio (Ψ = 1) one. The X-ray Diffraction results indicated rhombohedral phase (R3m) with JCPDS data card no: 72-2035. The ferroelectric transition of the sample at 8310C was detected by differential thermal analysis. Thermal analysis was done by Thermal gravimetric-Differential thermal analyzer and obtained results were presented in this paper.

  11. Concentration Quenching in Erbium Doped Bismuth Silicate Glasses

    Institute of Scientific and Technical Information of China (English)

    DAI Shi-Xun; XU Tie-Feng; NIE Qiu-Hua; SHEN Xiang; WANG Xun-Si

    2006-01-01

    @@ Er2 O3-doped bismuth silicate glasses are prepared by the conventional melt-quenching method, and the Er3+ : 4 I13/2 → 4I15/2 fluorescence properties are studied for different Er3+ concentrations. Infrared spectra are measured to estimate the exact content of OH- groups in the samples. Based on the electric dipole-dipole interaction theory,the interaction parameter CEr,Er for the migration rate of Er3+ :4 I13/2 → 4 I13/2 in proposed glasses is calculated.

  12. Coherent phonon coupling to individual Bloch states in photoexcited bismuth.

    Science.gov (United States)

    Papalazarou, E; Faure, J; Mauchain, J; Marsi, M; Taleb-Ibrahimi, A; Reshetnyak, I; van Roekeghem, A; Timrov, I; Vast, N; Arnaud, B; Perfetti, L

    2012-06-22

    We investigate the temporal evolution of the electronic states at the bismuth (111) surface by means of time- and angle-resolved photoelectron spectroscopy. The binding energy of bulklike bands oscillates with the frequency of the A(1g) phonon mode, whereas surface states are insensitive to the coherent displacement of the lattice. A strong dependence of the oscillation amplitude on the electronic wave vector is correctly reproduced by ab initio calculations of electron-phonon coupling. Besides these oscillations, all the electronic states also display a photoinduced shift towards higher binding energy whose dynamics follows the evolution of the electronic temperature.

  13. Low-temperature Hall effect in bismuth chalcogenides thin films

    Science.gov (United States)

    Kuntsevich, A. Yu.; Gabdullin, A. A.; Prudkogliad, V. A.; Selivanov, Yu. G.; Chizhevskii, E. G.; Pudalov, V. M.

    2016-12-01

    Bismuth chalcogenides are the most studied 3D topological insulators. As a rule, at low temperatures, thin films of these materials demonstrate positive magnetoresistance due to weak antilocalization. Weak antilocalization should lead to resistivity decrease at low temperatures; in experiments, however, resistivity grows as temperature decreases. From transport measurements for several thin films (with various carrier density, thickness, and carrier mobility), and by using a purely phenomenological approach, with no microscopic theory, we show that the low-temperature growth of the resistivity is accompanied by growth of the Hall coefficient, in agreement with the diffusive electron-electron interaction correction mechanism. Our data reasonably explain the low-temperature resistivity upturn.

  14. Sol-Gel Synthesis and Characterization of Cubic Bismuth Zinc Niobium Oxide Nanopowders

    Directory of Open Access Journals (Sweden)

    Ganchimeg Perenlei

    2014-01-01

    Full Text Available Bismuth zinc niobium oxide (BZN was successfully synthesized by a diol-based sol-gel reaction utilizing metal acetate and alkoxide precursors. Thermal analysis of a liquid suspension of precursors suggests that the majority of organic precursors decompose at temperatures up to 150°C, and organic free powders form above 350°C. The experimental results indicate that a homogeneous gel is obtained at about 200°C and then converts to a mixture of intermediate oxides at 350–400°C. Finally, single-phased BZN powders are obtained between 500 and 900°C. The degree of chemical homogeneity as determined by X-ray diffraction and EDS mapping is consistent throughout the samples. Elemental analysis indicates that the atomic ratio of metals closely matches a Bi1.5ZnNb1.5O7 composition. Crystallite sizes of the BZN powders calculated from the Scherrer equation are about 33–98 nm for the samples prepared at 500–700°C, respectively. The particle and crystallite sizes increase with increased sintering temperature. The estimated band gap of the BZN nanopowders from optical analysis is about 2.60–2.75 eV at 500-600°C. The observed phase formations and measured results in this study were compared with those of previous reports.

  15. Pathways for the release of polonium from a lead-bismuth spallation target (thermochemical calculation); Verfluechtigungspfade des Poloniums aus einem Pb-Bi-Spallationstarget (Thermochemische Kalkulation)

    Energy Technology Data Exchange (ETDEWEB)

    Eichler, B.; Neuhausen, J

    2004-06-01

    An analysis of literature data for the thermochemical constants of polonium reveals considerable discrepancies in the relations of these data among each other as well as in their expected trends within the chalcogen group. This fact hinders a reliable assessment of possible reaction paths for the release of polonium from a liquid lead-bismuth spallation target. In this work an attempt is made to construct a coherent data set for the thermochemical properties of polonium and some of its compounds that are of particular importance with respect to the behaviour of polonium in a liquid Pb-Bi target. This data set is based on extrapolations using general trends throughout the periodic table and, in particular, within the chalcogen group. Consequently, no high accuracy should be attributed to the derived data set. However, the data set derived in this work is consistent with definitely known experimental data. Furthermore, it complies with the general trends of physicochemical properties within the chalcogen group. Finally, well known relations between thermochemical quantities are fulfilled by the data derived in this work. Thus, given the lack of accurate experimental data it can be regarded as best available data. Thermochemical constants of polonium hydride, lead polonide and polonium dioxide are derived based on extrapolative procedures. Furthermore, the possibility of formation of the gaseous intermetallic molecule BiPo, which has been omitted from discussion up to now, is investigated. From the derived thermochemical data the equilibrium constants of formation, release and dissociation reactions are calculated for different polonium containing species. Furthermore equilibrium constants are determined for the reaction of lead polonide and polonium dioxide with hydrogen, water vapour and the target components lead and bismuth. The most probable release pathways are discussed. From thermochemical evaluations polonium is expected to be released from liquid lead-bismuth

  16. Focused ion beam processing to fabricate ohmic contact electrodes on a bismuth nanowire for Hall measurements.

    Science.gov (United States)

    Murata, Masayuki; Hasegawa, Yasuhiro

    2013-09-26

    Ohmic contact electrodes for four-wire resistance and Hall measurements were fabricated on an individual single-crystal bismuth nanowire encapsulated in a cylindrical quartz template. Focused ion beam processing was utilized to expose the side surfaces of the bismuth nanowire in the template, and carbon and tungsten electrodes were deposited on the bismuth nanowire in situ to achieve electrical contacts. The temperature dependence of the four-wire resistance was successfully measured for the bismuth nanowire, and a difference between the resistivities of the two-wire and four-wire methods was observed. It was concluded that the two-wire method was unsuitable for estimation of the resistivity due to the influence of contact resistance, even if the magnitude of the bismuth nanowire resistance was greater than the kilo-ohm order. Furthermore, Hall measurement of a 4-μm-diameter bismuth microwire was also performed as a trial, and the evaluated temperature dependence of the carrier mobility was in agreement with that for bulk bismuth, which indicates that the carrier mobility was successfully measured using this technique. PACS: 81.07.Gf.

  17. Surface-emitting laser logic

    Energy Technology Data Exchange (ETDEWEB)

    Olbright, G.R.; Bryan, R.P.; Brennan, T.M.; Lear, K.; Poirier, G.E.; Fu, W.S. (Sandia National Labs., Albuquerque, NM (USA)); Jewell, J.L.; Lee, Y.H. (AT and T Bell Labs., Holmdel, NJ (USA))

    1990-10-31

    We describe a new class of optical logic devices which consist of integrated phototransistors and surface-emitting lasers. The devices function as optical neurons having high gain and, as arrays, are ideal for neural networks, parallel optical signal processing and optical computing applications. 3 refs., 3 figs.

  18. Phase transition of solid bismuth under high pressure

    Science.gov (United States)

    Chen, Hai-Yan; Xiang, Shi-Kai; Yan, Xiao-Zhen; Zheng, Li-Rong; Zhang, Yi; Liu, Sheng-Gang; Bi, Yan

    2016-10-01

    As a widely used pressure calibrator, the structural phase transitions of bismuth from phase I, to phase II, to phase III, and then to phase V with increasing pressure at 300 K have been widely confirmed. However, there are different structural versions for phase III, most of which are determined by x-ray diffraction (XRD) technology. Using x-ray absorption fine structure (XAFS) measurements combined with ab initio calculations, we show that the proposed incommensurate composite structure of bismuth of the three configurations is the best option. An abnormal continuous increase of the nearest-neighbor distance of phase III with elevated pressure is also observed. The electronic structure transformation from semimetal to metal is responsible for the complex behavior of structure transformation. Project supported by the National Natural Science Foundation of China (Grant Nos. 10904133, 11304294, 11274281, 11404006, and U1230201), the Development Foundation of China Academy of Engineering Physics (Grant Nos. 2015B0101004, 2013B0401062, and 2012A0101001), the Research Foundation of the Laboratory of Shock Wave and Detonation, China (Grant No. 9140C670201140C67282).

  19. Genotoxic effects of bismuth (III oxide nanoparticles by comet assay

    Directory of Open Access Journals (Sweden)

    Reecep Liman

    2015-06-01

    Full Text Available Bismuth oxide is one of the important transition metal oxides and it has been intensively studied due to their peculiar characteristics (semiconductor band gap, high refractive index, high dielectric permittivity, high oxygen conductivity, resistivity, photoconductivity and photoluminescence etc.. Therefore, it is used such as microelectronics, sensor technology, optical coatings, transparent ceramic glass manufacturing, nanoenergetic gas generator, biosensor for DNA hybridization, potential immobilizing platforms for glucose oxidase and polyphenol oxidase, fuel cells, a additive in paints, an astringent in a variety of medical creams and topical ointments, and for the determination of heavy metal ions in drinking water, mineral water and urine. In addition this, Bismuth (III oxide nanoparticles (BONPs are favorable for the biomolecules adsorption than regular sized particles because of their greater advantages and novel characteristics (much higher specific surface, greater surface free energy, and good electrochemical stability etc.. Genotoxic effects of BONPs were investigated on the root cells of Allium cepa by Comet assay. A. cepa roots were treated with the aqueous dispersions of BONPs at 5 different concentrations (12.5, 25, 50, 75, and 100 ppm for 4 h. A significant increase in DNA damage was also observed at all concentrations of BONPs except 12.5 ppm by Comet assay. The results were also analyzed statistically by using SPSS for Windows; Duncan’s multiple range test was performed. These result indicate that BONPs exhibit genotoxic activity in A. cepa root meristematic cells.

  20. Nonproportionality in the scintillation light yield of bismuth germanate

    CERN Document Server

    Gentile, T R; Breuer, H; Chupp, T E; Coakley, K J; Cooper, R L; Nico, J S; O'Neill, B

    2015-01-01

    We present measurements of nonproportionality in the scintillation light yield of bismuth germanate (BGO) for gamma-rays with energies between 6 keV and 662 keV. The scintillation light was read out by avalanche photodiodes (APDs) with both the BGO crystals and APDs operated at a temperature of approximately 90 K. Data were obtained using radioisotope sources to illuminate both a single BGO crystal in a small test cryostat and a 12-element detector in a neutron radiative beta-decay experiment. In addition one datum was obtained in a 4.6 T magnetic field based on the bismuth K x-ray escape peak produced by a continuum of background gamma rays in this apparatus. These measurements and comparison to prior results were motivated by an experiment to study the radiative decay mode of the free neutron. The combination of data taken under different conditions yields a reasonably consistent picture for BGO nonproportionality that should be useful for researchers employing BGO detectors at low gamma ray energies.

  1. Synthesis and characterization of bismuth alkaline titanate powders

    Energy Technology Data Exchange (ETDEWEB)

    Torres-Huerta, A.M., E-mail: atorresh@ipn.mx [CICATA-Altamira, Instituto Politecnico Nacional, Km. 14.5 Carretera Tampico Puerto Industrial Altamira, Altamira, Tamps. 89600 (Mexico); Dominguez-Crespo, M.A. [CICATA-Altamira, Instituto Politecnico Nacional, Km. 14.5 Carretera Tampico Puerto Industrial Altamira, Altamira, Tamps. 89600 (Mexico); Hernandez-Perez, M.A. [ESIQIE, Metalurgia, Instituto Politecnico Nacional, Mexico, D. F (Mexico); Garcia-Zaleta, D.S. [CICATA-Altamira, Instituto Politecnico Nacional, Km. 14.5 Carretera Tampico Puerto Industrial Altamira, Altamira, Tamps. 89600 (Mexico); Brachetti-Sibaja, S.B. [CICATA-Altamira, Instituto Politecnico Nacional, Km. 14.5 Carretera Tampico Puerto Industrial Altamira, Altamira, Tamps. 89600 (Mexico); Instituto Tecnologico de Ciudad Madero, Av. 1o. de Mayo esq. Sor Juana Ines de la Cruz s/n Col. Los Mangos C.P.89440 Cd. Madero Tamaulipas (Mexico)

    2011-06-15

    In this work, samples of bismuth alkaline titanate, (K{sub 0.5}Na{sub 0.5}){sub (2-x/2)}Bi{sub (x/6)}TiO{sub 3}, (x = 0.05-0.75) have been prepared by conventional ceramic technique and molten salts. Metal oxides or carbonates powders were used as starting raw materials. The crystalline phase of the synthesized powders was identified by the X-ray diffraction (XRD) and particle morphology was characterized by scanning electron microscopy (SEM). Solid state reaction method was unsuccessful to obtain pellets. From XRD results, a rhombohedral structure was detected and the parameter lattice were estimated to be a = 5.5478 A and {alpha} = 59.48{sup o}. These parameters were used to refine the structure by Rietveld analysis. SEM results showed several morphologies. Apparently, bismuth is promoting the grain growth whose sizes vary from 30 nm to 180 nm It is expected that these materials can be utilized in practical applications as substitutes for lead zirconatetitanate (PZT)-based ceramics.

  2. Superconductivity in Bismuth. A New Look at an Old Problem.

    Directory of Open Access Journals (Sweden)

    Zaahel Mata-Pinzón

    Full Text Available To investigate the relationship between atomic topology, vibrational and electronic properties and superconductivity of bismuth, a 216-atom amorphous structure (a-Bi216 was computer-generated using our undermelt-quench approach. Its pair distribution function compares well with experiment. The calculated electronic and vibrational densities of states (eDOS and vDOS, respectively show that the amorphous eDOS is about 4 times the crystalline at the Fermi energy, whereas for the vDOS the energy range of the amorphous is roughly the same as the crystalline but the shapes are quite different. A simple BCS estimate of the possible crystalline superconducting transition temperature gives an upper limit of 1.3 mK. The e-ph coupling is more preponderant in a-Bi than in crystalline bismuth (x-Bi as indicated by the λ obtained via McMillan's formula, λc = 0.24 and experiment λa = 2.46. Therefore with respect to x-Bi, superconductivity in a-Bi is enhanced by the higher values of λ and of eDOS at the Fermi energy.

  3. New Bismuth-Substituted Hydroxyapatite Nanoparticles for Bone Tissue Engineering

    Science.gov (United States)

    Ciobanu, Gabriela; Bargan, Ana Maria; Luca, Constantin

    2015-11-01

    New bismuth-substituted hydroxyapatite [Ca10- x Bi x (PO4)6(OH)2 where x = 0-2.5] nanoparticles were synthesized by the co-precipitation method from aqueous solutions. The structural properties of the samples were analyzed by scanning electron microscopy coupled with x-ray analysis, x-ray powder diffraction, x-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and Brunauer-Emmett-Teller surface area analysis. The results confirm that bismuth ions have been incorporated into the hydroxyapatite lattice. The prepared nanocrystalline powders consisted of hydroxyapatite as single phase with hexagonal structure, crystal sizes smaller than 60 nm and (Bi + Ca)/P atomic ratio of around 1.67. The hydroxyapatite samples doped with Bi have mesoporous textures with pores size of around 2 nm and specific surface area in the range of 12-25 m2/g. The Bi-substituted hydroxyapatite powders are more effective against Gram-negative Escherichia coli bacteria than Gram-positive Staphylococcus aureus bacteria.

  4. Preparation and characterization of nanocrystalline powders of bismuth vanadate

    Energy Technology Data Exchange (ETDEWEB)

    Shantha, K.; Varma, K.B.R. [Indian Inst. of Science, Bangalore (India). Materials Research Centre

    1999-05-31

    The influence of mechanical activation on the formation of Bi{sub 2}VO{sub 5.5}, bismuth vanadate (BiV) phase, was investigated by ball-milling a stoichiometric mixture of bismuth oxide and vanadium pentoxide. The structural evolution of the desired BiV phase, via an intermediate BiVO{sub 4} phase, was investigated using X-ray powder diffraction (XRD), differential thermal analysis (DTA) and transmission electron microscopy (TEM). Milling for 54h yielded monophasic {gamma}-BiV powders with an average crystallite size of 30 nm. The electron paramagnetic resonance (EPR) peaks associated with the V{sup 4+} ions are stronger and broader in nanocrystalline (n) BiV than in the conventionally prepared microcrystalline (m) BiV, suggesting that a significant portion of V{sup 5+} has been transformed to V{sup 4+} during milling. The optical bandgap of n-BiV was found to be higher than that of m-BiV. High density (97% of the theoretical density), fine-grained (average grain-size of 2 {mu}m) ceramics with uniform grain-size distribution could be fabricated using n-BiV powders. These fine-grained ceramics exhibit improved dielectric, pyro and ferroelectric properties. (orig.) 29 refs.

  5. Magnetic properties of the binary Nickel/Bismuth alloy

    Science.gov (United States)

    Keskin, Mustafa; Şarlı, Numan

    2017-09-01

    Magnetic properties of the binary Nickel/Bismuth alloy (Ni/Bi) are investigated within the effective field theory. The Ni/Bi alloy has been modeled that the rhombohedral Bi lattice is surrounded by the hexagonal Ni lattice. According to lattice locations, Bi atoms have two different magnetic properties. Bi1 atoms are in the center of the hexagonal Ni atoms (Ni/Bi1 single layer) and Bi2 atoms are between two Ni/Bi1 bilayers. The Ni, Bi1, Bi2 and Ni/Bi undergo a second-order phase transition from the ferromagnetic phase to paramagnetic phase at Tc = 1.14. The magnetizations of the Ni/Bi alloy are observed as Bi1 > Bi2 > Ni/Bi > Ni at T < Tc; hence the magnetization of the Bi1 is dominant and Ni is at least dominant. However, the total magnetization of the Ni/Bi alloy is close to magnetization of the Ni at T < Tc. The corcivities of the Ni, Bi1, Bi2 and Ni/Bi alloy are the same with each others, but the remanence magnetizations are different. Our theoretical results of M(T) and M(H) of the Ni/Bi alloy are in quantitatively good agreement with the some experimental results of binary Nickel/Bismuth systems.

  6. Magnetic anisotropies in ultrathin bismuth iron garnet films

    Energy Technology Data Exchange (ETDEWEB)

    Popova, Elena, E-mail: popova@physique.uvsq.fr [Groupe d' Etude de la Matière Condensée (GEMaC), CNRS/Université de Versailles-Saint-Quentin, 45 Avenue des Etats-Unis, 78035 Versailles (France); Franco Galeano, Andres Felipe [Laboratoire PROcédés, Matériaux et Energie Solaire (PROMES), CNRS/Université de Perpignan Via Domitia, 52 Avenue Paul Alduy, 66860 Perpignan (France); Deb, Marwan [Groupe d' Etude de la Matière Condensée (GEMaC), CNRS/Université de Versailles-Saint-Quentin, 45 Avenue des Etats-Unis, 78035 Versailles (France); Warot-Fonrose, Bénédicte [Centre d' Elaboration de Matériaux et d' Etudes Structurales (CEMES), CNRS, 29 rue Jeanne Marvig, 31055 Toulouse (France); Transpyrenean Associated Laboratory for Electron Microscopy (TALEM), CEMES-INA, CNRS–Universidad de Zaragoza (Spain); Kachkachi, Hamid [Laboratoire PROcédés, Matériaux et Energie Solaire (PROMES), CNRS/Université de Perpignan Via Domitia, 52 Avenue Paul Alduy, 66860 Perpignan (France); Gendron, François [Institut des NanoSciences de Paris (INSP), CNRS/Université Pierre et Marie Curie-Paris 6, 4 place Jussieu, Boîte courrier 840, 75252 Paris Cedex 05 (France); Ott, Frédéric [Laboratoire Léon Brillouin (LLB), CNRS/CEA, Bâtiment 563, CEA Saclay, 91191 Gif sur Yvette Cedex (France); and others

    2013-06-15

    Ultrathin bismuth iron garnet Bi{sub 3}Fe{sub 5}O{sub 12} films were grown epitaxially on (001)-oriented gadolinium gallium garnet substrates. Film thickness varied from two to three dozens of unit cells. Bi{sub 3}Fe{sub 5}O{sub 12} films grow pseudomorphically on substrates up to a thickness of 20 nm, and then a lattice relaxation occurs. Magnetic properties of the films were studied as a function of bismuth iron garnet thickness. The magnetization and cubic anisotropy decrease with decreasing film thickness. The uniaxial magnetocrystalline anisotropy is constant for all film thicknesses. For two unit cell thick films, the easy magnetization axis changes from in-plane to perpendicular to the plane direction. Such a reorientation takes place as a result of the competition of constant uniaxial perpendicular anisotropy with weakening film magnetization. - Highlights: ► Ultrathin Bi{sub 3}Fe{sub 5}O{sub 12} films were grown epitaxially on structure-matching substrates. ► Magnetic properties of Bi{sub 3}Fe{sub 5}O{sub 12} were studied down to the thickness of 2.5 nm. ► Reorientation of easy magnetization axis as a function of film thickness was observed.

  7. Angle Dependence of the Orbital Magnetoresistance in Bismuth

    Directory of Open Access Journals (Sweden)

    Aurélie Collaudin

    2015-06-01

    Full Text Available We present an extensive study of angle-dependent transverse magnetoresistance in bismuth, with a magnetic field perpendicular to the applied electric current and rotating in three distinct crystallographic planes. The observed angular oscillations are confronted with the expectations of semiclassic transport theory for a multivalley system with anisotropic mobility and the agreement allows us to quantify the components of the mobility tensor for both electrons and holes. A quadratic temperature dependence is resolved. As Hartman argued long ago, this indicates that inelastic resistivity in bismuth is dominated by carrier-carrier scattering. At low temperature and high magnetic field, the threefold symmetry of the lattice is suddenly lost. Specifically, a 2π/3 rotation of magnetic field around the trigonal axis modifies the amplitude of the magnetoresistance below a field-dependent temperature. By following the evolution of this anomaly as a function of temperature and magnetic field, we map the boundary in the (field, temperature plane separating two electronic states. In the less symmetric state, confined to low temperature and high magnetic field, the three Dirac valleys cease to be rotationally invariant. We discuss the possible origins of this spontaneous valley polarization, including a valley-nematic scenario.

  8. Superconductivity in Bismuth. A New Look at an Old Problem

    Science.gov (United States)

    2016-01-01

    To investigate the relationship between atomic topology, vibrational and electronic properties and superconductivity of bismuth, a 216-atom amorphous structure (a-Bi216) was computer-generated using our undermelt-quench approach. Its pair distribution function compares well with experiment. The calculated electronic and vibrational densities of states (eDOS and vDOS, respectively) show that the amorphous eDOS is about 4 times the crystalline at the Fermi energy, whereas for the vDOS the energy range of the amorphous is roughly the same as the crystalline but the shapes are quite different. A simple BCS estimate of the possible crystalline superconducting transition temperature gives an upper limit of 1.3 mK. The e-ph coupling is more preponderant in a-Bi than in crystalline bismuth (x-Bi) as indicated by the λ obtained via McMillan’s formula, λc = 0.24 and experiment λa = 2.46. Therefore with respect to x-Bi, superconductivity in a-Bi is enhanced by the higher values of λ and of eDOS at the Fermi energy. PMID:26815431

  9. Bismuth Silver Oxysulfide for Photoconversion Applications: Structural and Optoelectronic Properties

    KAUST Repository

    baqais, amal

    2017-09-18

    Single-phase bismuth silver oxysulfide, BiAgOS, was prepared by a hydrothermal method. Its structural, morphological and optoelectronic properties were investigated and compared with bismuth copper oxysulfide (BiCuOS). Rietveld refinement of the powder X-ray diffraction (XRD) measurements revealed that the BiAgOS and BiCuOS crystals have the same structure as ZrSiCuAs: the tetragonal space group P4/nmm. X-ray photoelectron spectroscopy (XPS) analyses confirmed that the BiAgOS has a high purity, in contrast with BiCuOS, which tends to have Cu vacancies. The Ag has a monovalent oxidation state, whereas Cu is present in the oxidation states of +1 and +2 in the BiCuOS system. Combined with experimental measurements, density functional theory calculations employing the range-separated hybrid HSE06 exchange-correlation functional with spin-orbit coupling quantitatively elucidated photophysical properties such as ab-sorption coefficients, effective masses and dielectric constants. BiCuOS and BiAgOS were found to have indirect bandgaps of 1.1 and 1.5 eV, respectively. Both possess high dielectric constants and low electron and hole effective masses. Therefore, these materials are expected to have high exciton dissociation capabilities and excellent carrier diffusion properties. This study reveals that BiAgOS is a promising candidate for photoconversion applications.

  10. Solar Water Splitting and Nitrogen Fixation with Layered Bismuth Oxyhalides.

    Science.gov (United States)

    Li, Jie; Li, Hao; Zhan, Guangming; Zhang, Lizhi

    2017-01-17

    Hydrogen and ammonia are the chemical molecules that are vital to Earth's energy, environmental, and biological processes. Hydrogen with renewable, carbon-free, and high combustion-enthalpy hallmarks lays the foundation of next-generation energy source, while ammonia furnishes the building blocks of fertilizers and proteins to sustain the lives of plants and organisms. Such merits fascinate worldwide scientists in developing viable strategies to produce hydrogen and ammonia. Currently, at the forefronts of hydrogen and ammonia syntheses are solar water splitting and nitrogen fixation, because they go beyond the high temperature and pressure requirements of methane stream reforming and Haber-Bosch reaction, respectively, as the commercialized hydrogen and ammonia production routes, and inherit the natural photosynthesis virtues that are green and sustainable and operate at room temperature and atmospheric pressure. The key to propelling such photochemical reactions lies in searching photocatalysts that enable water splitting into hydrogen and nitrogen fixation to make ammonia efficiently. Although the past 40 years have witnessed significant breakthroughs using the most widely studied TiO2, SrTiO3, (Ga1-xZnx)(N1-xOx), CdS, and g-C3N4 for solar chemical synthesis, two crucial yet still unsolved issues challenge their further progress toward robust solar water splitting and nitrogen fixation, including the inefficient steering of electron transportation from the bulk to the surface and the difficulty of activating the N≡N triple bond of N2. This Account details our endeavors that leverage layered bismuth oxyhalides as photocatalysts for efficient solar water splitting and nitrogen fixation, with a focus on addressing the above two problems. We first demonstrate that the layered structures of bismuth oxyhalides can stimulate an internal electric field (IEF) that is capable of efficiently separating electrons and holes after their formation and of precisely channeling

  11. Bismuth ferrite as low-loss switchable material for plasmonic waveguide modulator

    DEFF Research Database (Denmark)

    Babicheva, Viktoriia; Zhukovsky, Sergei; Lavrinenko, Andrei

    2014-01-01

    We propose new designs of plasmonic modulators, which can beused for dynamic signal switching in photonic integrated circuits. We studyperformance of a plasmonic waveguide modulator with bismuth ferrite as atunable material. The bismuth ferrite core is sandwiched between metalplates (metal-insulator......-metal configuration), which also serve as electrodes.The core changes its refractive index by means of partial in-plane to out-of-plane reorientation of ferroelectric domains in bismuth ferrite under appliedvoltage. As a result, guided modes change their propagation constant andabsorption coefficient, allowing light...

  12. Is the ultra-fast transformation of bismuth non-thermal?

    CERN Document Server

    Gamaly, E G

    2009-01-01

    Transient state of femtosecond laser excited bismuth has been studied by various groups with time-resolved optical, x-ray, and electron probes at the deposited energy density from below through up to several times the equilibrium enthalpy of melting. However, the interpretations of the experimental results are controversial: the optical probes reveal the absence of transition to the melting phase while the authors of x-ray and electron diffraction experiments claim the observation of ultrafast non-thermal melting. The presented analysis, based on temperature dependence of bismuth optical properties, unequivocally shows a purely thermal nature of all the observed fs-laser induced transformations in bismuth.

  13. Exploiting Chemistry to Improve Performance of Screen-Printed, Bismuth Film Electrodes (SP-BiFE).

    Science.gov (United States)

    Dossi, Carlo; Monticelli, Damiano; Pozzi, Andrea; Recchia, Sandro

    2016-07-22

    Mercury substitution is a big issue in electroanalysis, and the search for a suitable, and less toxic, replacement is still under development. Of all the proposed alternatives, bismuth films appear to be the most viable solution, although they are still suffering some drawbacks, particularly the influence of deposition conditions and linearity at low concentrations. In this paper, the most promising strategies for bismuth film deposition on screen-printed electrodes (surface modifications, polymeric film deposition, insoluble salt precursors) will be evaluated for trace metal analysis. Particular attention will be devoted to bismuth chemistry, aiming to rationalize their electroanalytic performance.

  14. Oxidation mechanism of formic acid on the bismuth adatom-modified Pt(111) surface.

    Science.gov (United States)

    Perales-Rondón, Juan Victor; Ferre-Vilaplana, Adolfo; Feliu, Juan M; Herrero, Enrique

    2014-09-24

    In order to improve catalytic processes, elucidation of reaction mechanisms is essential. Here, supported by a combination of experimental and computational results, the oxidation mechanism of formic acid on Pt(111) electrodes modified by the incorporation of bismuth adatoms is revealed. In the proposed model, formic acid is first physisorbed on bismuth and then deprotonated and chemisorbed in formate form, also on bismuth, from which configuration the C-H bond is cleaved, on a neighbor Pt site, yielding CO2. It was found computationally that the activation energy for the C-H bond cleavage step is negligible, which was also verified experimentally.

  15. Exploiting Chemistry to Improve Performance of Screen-Printed, Bismuth Film Electrodes (SP-BiFE)

    Science.gov (United States)

    Dossi, Carlo; Monticelli, Damiano; Pozzi, Andrea; Recchia, Sandro

    2016-01-01

    Mercury substitution is a big issue in electroanalysis, and the search for a suitable, and less toxic, replacement is still under development. Of all the proposed alternatives, bismuth films appear to be the most viable solution, although they are still suffering some drawbacks, particularly the influence of deposition conditions and linearity at low concentrations. In this paper, the most promising strategies for bismuth film deposition on screen-printed electrodes (surface modifications, polymeric film deposition, insoluble salt precursors) will be evaluated for trace metal analysis. Particular attention will be devoted to bismuth chemistry, aiming to rationalize their electroanalytic performance. PMID:27455338

  16. Exploiting Chemistry to Improve Performance of Screen-Printed, Bismuth Film Electrodes (SP-BiFE

    Directory of Open Access Journals (Sweden)

    Carlo Dossi

    2016-07-01

    Full Text Available Mercury substitution is a big issue in electroanalysis, and the search for a suitable, and less toxic, replacement is still under development. Of all the proposed alternatives, bismuth films appear to be the most viable solution, although they are still suffering some drawbacks, particularly the influence of deposition conditions and linearity at low concentrations. In this paper, the most promising strategies for bismuth film deposition on screen-printed electrodes (surface modifications, polymeric film deposition, insoluble salt precursors will be evaluated for trace metal analysis. Particular attention will be devoted to bismuth chemistry, aiming to rationalize their electroanalytic performance.

  17. Development of oxygen meters for the use in lead-bismuth

    Science.gov (United States)

    Konys, J.; Muscher, H.; Voß, Z.; Wedemeyer, O.

    2001-07-01

    Liquid lead and the eutectic lead-bismuth alloy (PbBi) are considered both as a spallation target and coolant of an accelerator driven system (ADS) for the transmutation of long-lived actinides from nuclear waste into shorter living isotopes. It is known that both, pure lead and PbBi, exhibit a high corrosivity against austenitic and ferritic steels, because of the high solubility of nickel and iron in PbBi. One way of reducing the strong corrosion is the in situ formation of stable oxide scales on the steel surfaces. Thermodynamic calculations and experimental results have confirmed, that the control of oxygen in lead or PbBi within a defined activity range can lead to acceptable corrosion rates. To control the level of oxygen dissolved in lead or PbBi, a sensor for measuring the oxygen activity is required. Within the sodium fast breeder reactor development, an adequate technique was established for estimating oxygen in liquid sodium. This knowledge can be used for other metal/oxygen systems like oxygen in PbBi. For measuring the oxygen activity and calculating its concentration, the relevant thermodynamic and solubility data have to be considered. Two reference electrode systems: Pt/air and In/In 2O 3 (both based on yttria-stabilized zirconia as solid electrolyte) are investigated to evaluate their electromotive force (EMF)-temperature dependency in saturated and unsaturated oxygen solutions. Results with both types of oxygen meters in PbBi at different oxygen levels were compared with theoretical calculations. The experimental data indicate that the design, construction and integration of an oxygen control unit in a large scale PbBi-loop seems to be very feasible.

  18. Steels in interaction with liquid metals: a review; L'influence des metaux liquides sur les aciers inoxydables

    Energy Technology Data Exchange (ETDEWEB)

    Auger, T. [ECP/MSSMAT, UMR CNRS 8579, Grande voie des vignes, 92290 Chatenay-Malabry, (France)

    2011-07-01

    Liquid metals are envisaged for various nuclear applications ranging from spallation neutron sources to future fission and fusion reactors. A fair amount of current research is dedicated to the investigation of the interaction of steels, the only structural materials compatible at long term with liquid metals such as the eutectic lead-bismuth or sodium. The aging problems for these materials are corrosion, wettability and liquid metal induced embrittlement. This review recalls some of the key factors in the understanding of these problems. (authors)

  19. Liquids and liquid mixtures

    CERN Document Server

    Rowlinson, J S; Baldwin, J E; Buckingham, A D; Danishefsky, S

    2013-01-01

    Liquids and Liquid Mixtures, Third Edition explores the equilibrium properties of liquids and liquid mixtures and relates them to the properties of the constituent molecules using the methods of statistical thermodynamics. Topics covered include the critical state, fluid mixtures at high pressures, and the statistical thermodynamics of fluids and mixtures. This book consists of eight chapters and begins with an overview of the liquid state and the thermodynamic properties of liquids and liquid mixtures, including vapor pressure and heat capacities. The discussion then turns to the thermodynami

  20. Leaching process of anode slime with high silver and bismuth%高银铋阳极泥浸出工艺研究

    Institute of Scientific and Technical Information of China (English)

    何静; 郭瑞; 蓝明艳; 王灿; 鲁君乐

    2013-01-01

      某厂高银铋阳极泥产粗铋及综合回收有价金属,工艺采用两段浸出法处理此阳极泥,第1段硫酸浸出铜,第2段盐酸浸出铋.分别考察了浸出温度、时间、液固比(质量比)、酸量及氧化剂用量对浸出率的影响.铜的浸出率(液计)96%以上,铋、锑的浸出率(渣计)均在99%以上,铅、银富集于第2段浸出渣中,铅、银渣含Pb 26.63%左右,含Ag 36.77%左右,铅和银的直收率高,分别为97.82%及98.93%.浸出过程为串级联动循环浸出,洗酸洗水均返回下一次浸出,大大地减少了废水量,环境友好.%In order to produce crude bismuth and comprehensively recovery of valuable metals from anode slime with high silver and bismuth ,The process is Two-stage leaching. The first stage is leaching of copper with sulfuric acid and the second stage is leaching of bismuth with hydrochloric acid. Studied on the relationship between the Leaching rate and the leaching temperature, time, ratio of liquid to solid(Quality), dosage of acid and oxidant.The leaching rate (Liquid) of copper is above 96%,and The leaching rate (Slag) of bismuth and antimony are all above 99 %.The lead and silver are enriched in the second stage leaching slag, which containing Pb about 26.63%,Ag about 36.77 %,the direct yield of Pb and Ag are 97.82 % and 98.93 %respectively.The process is cycle leaching, washing water and washing acid are returned to the next leaching, which greatly reduced the amount of wastewater, and good for environmental protection.

  1. Potentiation of the action of metronidazole on Helicobacter pylori by omeprazole and bismuth subcitrate

    DEFF Research Database (Denmark)

    Andersen, L P; Colding, H; Kristiansen, J E

    2000-01-01

    Treatment failures using triple therapy that include metronidazole, are common in patients infected with metronidazole-resistant Helicobacter pylori in the gastric mucosa. Higher eradication rates in such patients have been described when treatment regimens include bismuth salts compared...

  2. In situ formation of bismuth nanoparticles through electron-beam irradiation in a transmission electron microscope

    Science.gov (United States)

    Sepulveda-Guzman, S.; Elizondo-Villarreal, N.; Ferrer, D.; Torres-Castro, A.; Gao, X.; Zhou, J. P.; Jose-Yacaman, M.

    2007-08-01

    In this work, bismuth nanoparticles were synthesized when a precursor, sodium bismuthate, was exposed to an electron beam at room temperature in a transmission electron microscope (TEM). The irradiation effects were investigated in situ using selected-area electron diffraction, high-resolution transmission electron microscopy and x-ray energy dispersive spectroscopy. After the electron irradiation, bismuth nanoparticles with a rhombohedral structure and diameter of 6 nm were observed. The average particle size increased with the irradiation time. The electron-induced reduction is attributed to the desorption of oxygen ions. This method offers a one-step route to synthesize bismuth nanoparticles using electron irradiation, and the particle size can be controlled by the irradiation time.

  3. In situ formation of bismuth nanoparticles through electron-beam irradiation in a transmission electron microscope

    Energy Technology Data Exchange (ETDEWEB)

    Sepulveda-Guzman, S; Elizondo-Villarreal, N; Ferrer, D; Torres-Castro, A; Gao, X; Zhou, J P; Jose-Yacaman, M [Chemical Engineering Department and Texas Materials Institute, University of Texas at Austin, Austin, TX 78712 (United States)

    2007-08-22

    In this work, bismuth nanoparticles were synthesized when a precursor, sodium bismuthate, was exposed to an electron beam at room temperature in a transmission electron microscope (TEM). The irradiation effects were investigated in situ using selected-area electron diffraction, high-resolution transmission electron microscopy and x-ray energy dispersive spectroscopy. After the electron irradiation, bismuth nanoparticles with a rhombohedral structure and diameter of 6 nm were observed. The average particle size increased with the irradiation time. The electron-induced reduction is attributed to the desorption of oxygen ions. This method offers a one-step route to synthesize bismuth nanoparticles using electron irradiation, and the particle size can be controlled by the irradiation time.

  4. RECYCLING TECHNOLOGY INTO INDUSTRIAL TURNOVER OF BISMUTH AND MOLYBDENUM FROM DEAD CATALYST

    Directory of Open Access Journals (Sweden)

    O. S. Komarov

    2013-01-01

    Full Text Available The technology of separate extraction of bismuth and molybdenum from spent catalyst was presented and information on the effectiveness of its use in a composition of comprehensive modifier in the iron-carbon alloy was given.

  5. Three-component synthesis of amidoalkyl naphthols catalyzed by bismuth(Ⅲ) nitrate pentahydrate

    Institute of Scientific and Technical Information of China (English)

    Min Wang; Yan Liang; Ting Ting Zhang; Jing Jing Gao

    2012-01-01

    Bismuth(Ⅲ) nitrate pentahydrate catalyzed the three-component condensation of β-naphthol,aldehydes and amines/urea under solvent-free conditions to afford the corresponding amidoalkyl naphthols in excellent yields.

  6. Reactive magnetron sputtering deposition of bismuth tungstate onto titania nanoparticles for enhancing visible light photocatalytic activity

    Science.gov (United States)

    Ratova, Marina; Kelly, Peter J.; West, Glen T.; Tosheva, Lubomira; Edge, Michele

    2017-01-01

    Titanium dioxide - bismuth tungstate composite materials were prepared by pulsed DC reactive magnetron sputtering of bismuth and tungsten metallic targets in argon/oxygen atmosphere onto anatase and rutile titania nanoparticles. The use of an oscillating bowl placed beneath the two magnetrons arranged in a co-planar closed field configuration enabled the deposition of bismuth tungstate onto loose powders, rather than a solid substrate. The atomic ratio of the bismuth/tungsten coatings was controlled by varying the power applied to each target. The effect of the bismuth tungstate coatings on the phase, optical and photocatalytic properties of titania was investigated by X-ray diffraction, energy-dispersive X-ray spectroscopy (EDX), Brunauer-Emmett-Teller (BET) surface area measurements, transmission electron microscopy (TEM), UV-vis diffuse reflectance spectroscopy and an acetone degradation test. The latter involved measurements of the rate of CO2 evolution under visible light irradiation of the photocatalysts, which indicated that the deposition of bismuth tungstate resulted in a significant enhancement of visible light activity, for both anatase and rutile titania particles. The best results were achieved for coatings with a bismuth to tungsten atomic ratio of 2:1. In addition, the mechanism by which the photocatalytic activity of the TiO2 nanoparticles was enhanced by compounding it with bismuth tungstate was studied by microwave cavity perturbation. The results of these tests confirmed that such enhancement of the photocatalytic properties is due to more efficient photogenerated charge carrier separation, as well as to the contribution of the intrinsic photocatalytic properties of Bi2WO6.

  7. Aluminium bismuthate nanorods and the electrochemical performance for detection of tartaric acid

    Energy Technology Data Exchange (ETDEWEB)

    Pei, L.Z., E-mail: lzpei@ahut.edu.cn [Key Lab of Materials Science and Processing of Anhui Province, School of Materials Science and Engineering, Anhui University of Technology, Ma' anshan, Anhui 243002 (China); Wei, T.; Lin, N.; Fan, C.G. [Key Lab of Materials Science and Processing of Anhui Province, School of Materials Science and Engineering, Anhui University of Technology, Ma' anshan, Anhui 243002 (China); Yang, Zao, E-mail: yangzao888@tom.com [National Engineering Research Center for Biomaterials, Sichuan University, Chengdu, Sichuan 610064 (China)

    2016-09-15

    Aluminium bismuthate nanorods had been synthesized by a facile hydrothemral method. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations showed that the lengh and diameter were 2–10 μm and 50–200 nm, respectively. X-ray diffraction (XRD) and high-resolution TEM (HRTEM) showed that the nanorods were composed of single crystalline orthorhombic Al{sub 4}Bi{sub 2}O{sub 9} phase. The aluminium bismuthate nanorods could be explained by the nucleation and crystalline growth process based on the products obtained from different hydrothermal conditions. Aluminium bismuthate nanorods modified glassy carbon electrode (GCE) was fabricated for the electrochemical detection of tartaric acid (TA) in neutral solution. A pair of semi-reversible redox peaks located at −0.08 V and −0.53 V, respectively were observed. The current intensity of the cyclic voltammogram (CV) peak increased linearly obviously with increasing the scan rate and TA concentration. The detection limit and linear range were 0.64 μM and 0.001–2 mM, respectively with the correlation coefficient of 0.995. The aluminium bismuthate nanorods modified GCE had good reproducibility and stability for the detection of TA. - Highlights: • Aluminium bismuthate nanorods were synthesized by a facile hydrothermal process. • The size of aluminium bismuthate nanorods could be controlled by growth conditions. • Aluminium bismuthate nanorods showed good electrochemical performance for the detection of tartaric acid. • Aluminium bismuthate nanorods modified GCE had good reproducibility and stability.

  8. Evaluation of the usefulness of bismuth shields in PET/CT examination

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hoon Hee; Lyu, Kwang Yeul [Dept. of Radiological Technology, Shingu College, Sungnam (Korea, Republic of); Lee, Ju Young [Graduate School of Public Health, Yonsei Universtiy, Seoul (Korea, Republic of); Kim, Ji Hyeon [Dept. of Nuclear Medicine, Seoul Medical Center, Seoul (Korea, Republic of); Kung, Sik Nam [Dept. of Nuclear Medicine, Konkuk Univeristy Medical Center, Seoul (Korea, Republic of); Lee, Tae Soo [Dept. of Biomedical Enginnering, Chugnbuk National University, Junju (Korea, Republic of)

    2014-03-15

    Recently with CT developed, various studies for reduction of exposure dose is underway. Study of bismuth shields in these studies is actively underway, and has already been applied in the clinical. However, the application of the PET/CT examination was not activated. Therefore, through this study, depending on the application of bismuth shields in the PET/CT examination, we identify the quality of the image and the impact on the Standard Uptake Value (SUV). In this study, to apply to the shielding of the breast, by using the bismuth shields that contains 0.06 mm Pb ingredients, was applied to the PET/CT GEMINI TF 64 (Philips Healthcare, Cleveland, USA). Phantom experiments using the NEMA IEC Body Phantom, images were acquired according to the presence or absence of bismuth shields apply. Also, When applying, images were obtained by varying the spacing 0, 1, 2 cm each image set to the interest range in the depth of the phantom by using EBW-NM ver.1.0. When image of the PET Emission acquires, the SUV was in increased depending on the use of bismuth shields, difference in the depth to the surface from deep in the phantom increasingly SUV increased (P<0.005). Also, when using shields, as the more gab decreased, SUV is more increased (P<0.005). Through this study, PET/CT examination by using of bismuth shields which is used as purpose of reduction dose. When using shields, the difference of SUV resulting from the application of bismuth shields exist and that difference when gab is decrease and surface is wider. Therefore, setting spacing of shield should be considered, if considering the reduction of the variation of SUV and image quality, disease of deep organs should be a priority rather than superficial organ disease. Use of bismuth shielding factor considering the standard clinical examination, decrease unnecessary exposure can be expected to be considered.

  9. Effects of bismuth vandate and anthraquinone dye on the photodegradation of polycarbonate

    OpenAIRE

    Saron,Clodoaldo; Felisberti, Maria Isabel; Zulli, Fabio; Giordano, Marco

    2007-01-01

    Both inorganic and organic compounds, such as oxides or salts of metals and polycyclic and azo compounds, are frequently used as colorants in polymeric systems. Bismuth vanadate pigment has been used as an environmentally friendly alternative for cadmium containing pigments and anthraquinone dyes represent a polycyclic colorant class of wide use in polymers. Besides their coloring properties, both bismuth vanadate and anthraquinone present photocatalytic activity or photochemical properties t...

  10. Bismuth ferrite as low-loss switchable material for plasmonic waveguide modulator

    OpenAIRE

    Babicheva, Viktoriia; Zhukovsky, Sergei; Lavrinenko, Andrei

    2014-01-01

    We propose new designs of plasmonic modulators, which can be utilized for dynamic signal switching in photonic integrated circuits. We study performance of plasmonic waveguide modulator with bismuth ferrite as an active material. The bismuth ferrite core is sandwiched between metal plates (metal-insulator-metal configuration), which also serve as electrodes so that the core changes its refractive index under applied voltage by means of partial in-plane to out-of-plane reorientation of ferroel...

  11. Exhaustive removal of chloride ions from water with the aid of a bismuth-based metallic sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Moskvin, L.N.; Ushenko, V.G.

    1988-04-20

    The authors discuss the sorption properties of sorbents based on metallic bismuth, in relation to a solution of the problem of exhaustive removal of chloride ions from water. Metallic sorbents with bismuth contents of 10 mass % on polytetrafluoroethylene were used. The sorption properties of sorbents based on metallic bismuth and on Bi/sub 2/O/sub 3/ were studied under dynamic conditions. Their results show that bismuth-based metal sorbents and sorbents based on bismuth oxide can be used as inorganic anion-exchangers. In order to demonstrate the possibility of selective separation of chloride ions from solutions they determined the dynamic exchange capacity for chloride ions at various nitrate-ion concentrations. The use of the proposed sorbents based on metallic bismuth for exhaustive purification of water lowers the chloride-ion concentration in the water sharply in comparison with the level achieved by ion-exchange purification with the aid of organic anion-exchangers.

  12. A novel synthesis of perovskite bismuth ferrite nanoparticles

    Directory of Open Access Journals (Sweden)

    Alexandre Z. Simões

    2011-09-01

    Full Text Available Microwave assisted hydrothermal (MAH method was used to synthesize crystalline bismuth ferrite (BiFeO3 nanoparticles (BFO at temperature of 180°C with times ranging from 5 min to 1 h. For comparison, BFO powders were also crystallized by the soft chemistry route in a conventional furnace at a temperature of 850°C for 4 h. X-ray diffraction (XRD results verified the formation of perovskite BFO crystallites while infrared data showed no traces of carbonate. Field emission scanning microcopy (FE/SEM revealed a homogeneous size distribution of nanometric BFO powders. MAH method produced nanoparticles of 96% pure perovskite, with a size of 130 nm. These results are in agreement with Raman scattering values which show that the MAH synthesis route is rapid and cost effective. This method could be used as an alternative to other chemical methods in order to obtain BFO nanoparticles.

  13. Structural investigation of Zn doped sodium bismuth borate glasses

    Science.gov (United States)

    Bhatia, V.; Kumar, D.; Singh, D.; Singh, S. P.

    2016-05-01

    A series of Bismuth Borate Oxide Glass samples with composition x(ZnO):(15-x)Na2O:15Bi2O3:70B2O3 (variation in x is from 6 to 12 mole %) have been prepared by conventional melt quenching technique. All the chemicals used were of Analytical Grade. In order to verify the amorphous nature of the prepared samples the X-Ray Diffraction (XRD) was done. The physical and structural properties have been explored by using the techniques such as density, molar volume and FTIR in order to understand the effect of alkali and transition metal ions on the structure of these glasses. The results obtained by these techniques are in good agreement to one another and with literature as well. With the increase in the content of ZnO, the increase in density and some variations in structural coordination (ratio of BO3 & BO4 structural units) have been observed.

  14. Process dependent thermoelectric properties of EDTA assisted bismuth telluride

    Science.gov (United States)

    Kulsi, Chiranjit; Kargupta, Kajari; Banerjee, Dipali

    2016-04-01

    Comparison between the structure and thermoelectric properties of EDTA (Ethylene-diamine-tetra-acetic acid) assisted bismuth telluride prepared by electrochemical deposition and hydrothermal route is reported in the present work. The prepared samples have been structurally characterized by high resolution X-ray diffraction spectra (HRXRD), field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopic images (HRTEM). Crystallite size and strain have been determined from Williamson-Hall plot of XRD which is in conformity with TEM images. Measurement of transport properties show sample in the pellet form (S1) prepared via hydrothermal route has higher value of thermoelectric power (S) than the electrodeposited film (S2). But due to a substantial increase in the electrical conductivity (σ) of the film (S2) over the pellet (S1), the power factor and the figure of merit is higher for sample S2 than the sample S1 at room temperature.

  15. High thermoelectric performance of the distorted bismuth(110) layer.

    Science.gov (United States)

    Cheng, L; Liu, H J; Zhang, J; Wei, J; Liang, J H; Jiang, P H; Fan, D D; Sun, L; Shi, J

    2016-07-14

    The thermoelectric properties of the distorted bismuth(110) layer are investigated using first-principles calculations combined with the Boltzmann transport equation for both electrons and phonons. To accurately predict the electronic and transport properties, the quasiparticle corrections with the GW approximation of many-body effects have been explicitly included. It is found that a maximum ZT value of 6.4 can be achieved for n-type systems, which essentially stemmed from the weak scattering of electrons. Moreover, we demonstrate that the distorted Bi layer retains high ZT values in relatively broad regions of both temperature and carrier concentration. Our theoretical work emphasizes that the deformation potential constant characterizing the electron-phonon scattering strength is an important paradigm for searching high thermoelectric performance materials.

  16. High ionic conductivity in confined bismuth oxide-based heterostructures

    Science.gov (United States)

    Sanna, Simone; Esposito, Vincenzo; Christensen, Mogens; Pryds, Nini

    2016-12-01

    Bismuth trioxide in the cubic fluorite phase (δ -Bi2O3 ) exhibits the highest oxygen ionic conductivity. In this study, we were able to stabilize the pure δ -Bi2O3 at low temperature with no addition of stabilizer but only by engineering the interface, using highly coherent heterostructures made of alternative layers of δ -Bi2O3 and Yttria Stabilized Zirconia (YSZ), deposited by pulsed laser deposition. The resulting [δ -Bi2O3 /YSZ ] heterostructures are found to be stable over a wide temperature range (500-750 °C) and exhibits stable high ionic conductivity over a long time comparable to the value of the pure δ -Bi2O3 , which is approximately two orders of magnitude higher than the conductivity of YSZ bulk.

  17. Bismuth Sodium Titanate Based Materials for Piezoelectric Actuators.

    Science.gov (United States)

    Reichmann, Klaus; Feteira, Antonio; Li, Ming

    2015-12-04

    The ban of lead in many electronic products and the expectation that, sooner or later, this ban will include the currently exempt piezoelectric ceramics based on Lead-Zirconate-Titanate has motivated many research groups to look for lead-free substitutes. After a short overview on different classes of lead-free piezoelectric ceramics with large strain, this review will focus on Bismuth-Sodium-Titanate and its solid solutions. These compounds exhibit extraordinarily high strain, due to a field induced phase transition, which makes them attractive for actuator applications. The structural features of these materials and the origin of the field-induced strain will be revised. Technologies for texturing, which increases the useable strain, will be introduced. Finally, the features that are relevant for the application of these materials in a multilayer design will be summarized.

  18. Formic Acid Oxidation at Platinum-Bismuth Clusters

    DEFF Research Database (Denmark)

    Lovic, J. D.; Stevanovic, S. I.; Tripkovic, D. V.

    2014-01-01

    Formic acid oxidation was studied on platinum-bismuth deposits on glassy carbon (GC) substrate. The catalysts of equimolar ratio were prepared by potentiostatic deposition using chronocoulometry. Bimetallic structures obtained by two-step process, comprising deposition of Bi followed by deposition...... of Pt, were characterized by AFM spectroscopy which indicated that Pt crystallizes preferentially onto previously formed Bi particles. The issue of Bi leaching (dissolution) from PtBi catalysts, and their catalytic effect alongside the HCOOH oxidation is rather unresolved. In order to control Bi...... dissolution, deposits were subjected to electrochemical oxidation, in the relevant potential range and supporting electrolyte, prior to use as catalysts for HCOOH oxidation. Anodic striping charges indicated that along oxidation procedure most of deposited Bi was oxidized. ICP mass spectroscopy analysis...

  19. Bismuth Sodium Titanate Based Materials for Piezoelectric Actuators

    Directory of Open Access Journals (Sweden)

    Klaus Reichmann

    2015-12-01

    Full Text Available The ban of lead in many electronic products and the expectation that, sooner or later, this ban will include the currently exempt piezoelectric ceramics based on Lead-Zirconate-Titanate has motivated many research groups to look for lead-free substitutes. After a short overview on different classes of lead-free piezoelectric ceramics with large strain, this review will focus on Bismuth-Sodium-Titanate and its solid solutions. These compounds exhibit extraordinarily high strain, due to a field induced phase transition, which makes them attractive for actuator applications. The structural features of these materials and the origin of the field-induced strain will be revised. Technologies for texturing, which increases the useable strain, will be introduced. Finally, the features that are relevant for the application of these materials in a multilayer design will be summarized.

  20. One-dimensional topological edge states of bismuth bilayers

    Science.gov (United States)

    Drozdov, Ilya K.; Alexandradinata, A.; Jeon, Sangjun; Nadj-Perge, Stevan; Ji, Huiwen; Cava, R. J.; Andrei Bernevig, B.; Yazdani, Ali

    2014-09-01

    The hallmark of a topologically insulating state of matter in two dimensions protected by time-reversal symmetry is the existence of chiral edge modes propagating along the perimeter of the sample. Among the first systems predicted to be a two-dimensional topological insulator are bilayers of bismuth. Here we report scanning tunnelling microscopy experiments on bulk Bi crystals that show that a subset of the predicted Bi-bilayers' edge states are decoupled from the states of the substrate and provide direct spectroscopic evidence of their one-dimensional nature. Moreover, by visualizing the quantum interference of edge-mode quasi-particles in confined geometries, we demonstrate their remarkable coherent propagation along the edge with scattering properties consistent with strong suppression of backscattering as predicted for the propagating topological edge states.

  1. High ionic conductivity in confined bismuth oxide-based heterostructures

    Directory of Open Access Journals (Sweden)

    Simone Sanna

    2016-12-01

    Full Text Available Bismuth trioxide in the cubic fluorite phase (δ-Bi2O3 exhibits the highest oxygen ionic conductivity. In this study, we were able to stabilize the pure δ-Bi2O3 at low temperature with no addition of stabilizer but only by engineering the interface, using highly coherent heterostructures made of alternative layers of δ-Bi2O3 and Yttria Stabilized Zirconia (YSZ, deposited by pulsed laser deposition. The resulting [δ-Bi2O3/YSZ] heterostructures are found to be stable over a wide temperature range (500-750 °C and exhibits stable high ionic conductivity over a long time comparable to the value of the pure δ-Bi2O3, which is approximately two orders of magnitude higher than the conductivity of YSZ bulk.

  2. Spark plasma sintering of hydrothermally synthesized bismuth ferrite

    Directory of Open Access Journals (Sweden)

    Zorica Branković

    2016-12-01

    Full Text Available Bismuth ferrite, BiFeO3 (BFO, powder was synthesized by hydrothermal method from Bi(NO33·5 H2O and Fe(NO33·9 H2O as precursors. The synthesized powder was further sintered using spark plasma sintering (SPS. The sintering conditions were optimized in order to achieve high density, minimal amount of secondary phases and improved ferroelectric and magnetic properties. The optimal structure and properties were achieved after spark plasma sintering at 630 °C for 20 min, under uniaxial pressure of 90 MPa. The composition, microstructure, ferroelectric and magnetic properties of the SPS samples were characterized and compared to those of conventionally sintered ceramics obtained from the same powder. Although the samples sintered using conventional method showed slightly lower amount of secondary phases, the spark plasma sintered samples exhibited favourable microstructure and better ferroelectric properties.

  3. Shock-Wave Consolidation of Nanostructured Bismuth Telluride Powders

    Science.gov (United States)

    Beck, Jan; Alvarado, Manuel; Nemir, David; Nowell, Mathew; Murr, Lawrence; Prasad, Narasimha

    2012-06-01

    Nanostructured thermoelectric powders can be produced using a variety of techniques. However, it is very challenging to build a bulk material from these nanopowders without losing the nanostructure. In the present work, nanostructured powders of the bismuth telluride alloy system are obtained in kilogram quantities via a gas atomization process. These powders are characterized using a variety of methods including scanning electron microscopy, transition electron microscopy, and x-ray diffraction analysis. Then the powders are consolidated into a dense bulk material using a shock-wave consolidation technique whereby a nanopowder-containing tube is surrounded by explosives and then detonated. The resulting shock wave causes rapid fusing of the powders without the melt and subsequent grain growth of other techniques. We describe the test setup and consolidation results.

  4. Bismuth coatings deposited by the pulsed dc sputtering technique

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz, M. F.; Olaya, J. J.; Alfonso, J. E., E-mail: jealfonsoo@unal.edu.co [Universidad Nacional de Colombia, Departamento de Fisica, Grupo de Ciencia de Materiales y Superficies, Carrera 45 No. 26-85, Edif. Uriel Gutierrez, Bogota D. C. (Colombia)

    2013-08-01

    In this work we present the results obtained from the deposition of nano-structured bismuth coatings through Dc pulsed unbalanced magnetron sputtering. The coatings were grown on two substrates: silicon and AISI steel 316 L. The microstructure of the Bi coatings grown on silicon and the corrosion resistance of the Bi coatings grown on AISI steel were evaluated. The microstructure was evaluated by X-ray diffraction and the corrosion resistance was characterized by means of polarization potentiodynamic and electrochemical impedance spectroscopy. Finally the morphology of the coatings was evaluated through scanning electronic microscopy. The X-ray diffraction analysis indicates that the coatings are polycrystalline; the corrosion resistance tests indicate that the films with better corrosion resistance were deposited at 40 khz. Scanning electron microscopy micrographs show that the coatings are grown as granular form. (Author)

  5. Nano sized bismuth oxy chloride by metal organic chemical vapour deposition

    Energy Technology Data Exchange (ETDEWEB)

    Jagdale, Pravin, E-mail: pravin.jagdale@polito.it [Department of Applied Science and Technology (DISAT), Politecnico di Torino, 10129 (Italy); Castellino, Micaela [Center for Space Human Robotics, Istituto Italiano di Tecnologia, Corso Trento 21, 10129 Torino (Italy); Marrec, Françoise [Laboratory of Condensed Matter Physics, University of Picardie Jules Verne (UPJV), Amiens 80039 (France); Rodil, Sandra E. [Instituto de Investigaciones en Materiales, Universidad Nacional Autonoma de Mexicom (UNAM), Mexico D.F. 04510 (Mexico); Tagliaferro, Alberto [Department of Applied Science and Technology (DISAT), Politecnico di Torino, 10129 (Italy)

    2014-06-01

    Metal organic chemical vapour deposition (MOCVD) method was used to prepare thin films of bismuth based nano particles starting from bismuth salts. Nano sized bismuth oxy chloride (BiOCl) crystals were synthesized from solution containing bismuth chloride (BiCl{sub 3}) in acetone (CH{sub 3}-CO-CH{sub 3}). Self-assembly of nano sized BiOCl crystals were observed on the surface of silicon, fused silica, copper, carbon nanotubes and aluminium substrates. Various synthesis parameters and their significant impact onto the formation of self-assembled nano-crystalline BiOCl were investigated. BiOCl nano particles were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy and Micro-Raman spectroscopy. These analyses confirm that bismuth nanometer-sized crystal structures showing a single tetragonal phase were indeed bismuth oxy chloride (BiOCl) square platelets 18–250 nm thick and a few micrometres wide.

  6. Large-Area Dry Transfer of Single-Crystalline Epitaxial Bismuth Thin Films.

    Science.gov (United States)

    Walker, Emily S; Na, Seung Ryul; Jung, Daehwan; March, Stephen D; Kim, Joon-Seok; Trivedi, Tanuj; Li, Wei; Tao, Li; Lee, Minjoo L; Liechti, Kenneth M; Akinwande, Deji; Bank, Seth R

    2016-11-09

    We report the first direct dry transfer of a single-crystalline thin film grown by molecular beam epitaxy. A double cantilever beam fracture technique was used to transfer epitaxial bismuth thin films grown on silicon (111) to silicon strips coated with epoxy. The transferred bismuth films retained electrical, optical, and structural properties comparable to the as-grown epitaxial films. Additionally, we isolated the bismuth thin films on freestanding flexible cured-epoxy post-transfer. The adhesion energy at the bismuth/silicon interface was measured to be ∼1 J/m(2), comparable to that of exfoliated and wet transferred graphene. This low adhesion energy and ease of transfer is unexpected for an epitaxially grown film and may enable the study of bismuth's unique electronic and spintronic properties on arbitrary substrates. Moreover, this method suggests a route to integrate other group-V epitaxial films (i.e., phosphorus) with arbitrary substrates, as well as potentially to isolate bismuthene, the atomic thin-film limit of bismuth.

  7. Adverse events with bismuth salts for Helicobacter pylori eradication:Systematic review and meta-analysis

    Institute of Scientific and Technical Information of China (English)

    Alexander C Ford; Peter Malfertheiner; Monique Giguére; José Santana; Mostafizur Khan; Paul Moayyedi

    2008-01-01

    AIM:To assess the safety of bismuth used in Helicobacter pylori (H pylori) eradication therapy regimens.METHODS:We conducted a systematic review and meta-analysis.MEDLINE and EMBASE were searched (up to October 2007) to identify randomised controlled trials comparing bismuth with placebo or no treatment,or bismuth salts in combination with antibiotics as part of eradication therapy with the same dose and duration of antibiotics alone or,in combination,with acid suppression.Total numbers of adverse events were recorded.Data were pooled and expressed as relative risks with 95% confidence intervals (CI).RESULTS:We identified 35 randomised controlled trials containing 4763 patients.There were no serious adverse events occurring with bismuth therapy.There was no statistically significant difference detected in total adverse events with bismuth [relative risk (RR)=1.01;95% CI:0.87-1.16],specific individual adverse events,with the exception of dark stools (RR = 5.06;95% CI:1.59-16.12),or adverse events leading to withdrawal of therapy (RR = 0.86;95% CI:0.54-1.37).CONCLUSION:Bismuth for the treatment of H pylori is safe and well-tolerated.The only adverse event occurring significantly more commonly was dark stools.

  8. Viability of Bismuth as a Green Substitute for Lead in Jacketed .357 Magnum Revolver Bullets

    Science.gov (United States)

    Jenkins, Joel

    In seeking to develop environmentally friendly lead-free non-toxic bullets, the research ballistically evaluated the performance of copper-jacketed handgun bullets containing a pure bismuth core. The lead was first removed from 140 grain Hornady(TM) XTPRTM bullets of 38 caliber (.357 diameter) by melting. The empty jackets were then refilled with pure bismuth, including the forming of a correctly sized hollow-point cavity. Due to the lower density of bismuth as compared to lead, the bismuth-cored bullets consistently weighed 125 gains. Conveniently this allowed direct comparison to commercially available 125 grain Hornady(TM) XTPRTM lead-cored bullets of 38 caliber. Both bismuth-cored and lead-cored versions of the 125 grain bullets had identical nose dimensions and jacket material, the only dimensional difference being the bullet length below the cannelure. Shooting took place at an outdoor range using a 357 Magnum Ruger(TM) SP101RTM revolver with 3" barrel as the test weapon. FBI protocols were followed when firing through clothing, wallboard, plywood, steel plates and laminated glass. Wound paths and bullets were captured in ballistic gelatin, with data collected for velocity, penetration, expansion, and weight retention. Bismuth compared favorably with lead in all but the laminated glass test, where it under penetrated due to jacket separation.

  9. Zerovalent bismuth nanoparticles inhibit Streptococcus mutans growth and formation of biofilm

    Science.gov (United States)

    Hernandez-Delgadillo, Rene; Velasco-Arias, Donaji; Diaz, David; Arevalo-Niño, Katiushka; Garza-Enriquez, Marianela; De la Garza-Ramos, Myriam A; Cabral-Romero, Claudio

    2012-01-01

    Background and methods Despite continuous efforts, the increasing prevalence of resistance among pathogenic bacteria to common antibiotics has become one of the most significant concerns in modern medicine. Nanostructured materials are used in many fields, including biological sciences and medicine. While some bismuth derivatives has been used in medicine to treat vomiting, nausea, diarrhea, and stomach pain, the biocidal activity of zerovalent bismuth nanoparticles has not yet been studied. The objective of this investigation was to analyze the antimicrobial activity of bismuth nanoparticles against oral bacteria and their antibiofilm capabilities. Results Our results showed that stable colloidal bismuth nanoparticles had 69% antimicrobial activity against Streptococcus mutans growth and achieved complete inhibition of biofilm formation. These results are similar to those obtained with chlorhexidine, the most commonly used oral antiseptic agent. The minimal inhibitory concentration of bismuth nanoparticles that interfered with S. mutans growth was 0.5 mM. Conclusion These results suggest that zerovalent bismuth nanoparticles could be an interesting antimicrobial agent to be incorporated into an oral antiseptic preparation. PMID:22619547

  10. Wine as a digestive aid: comparative antimicrobial effects of bismuth salicylate and red and white wine.

    Science.gov (United States)

    Weisse, M. E.; Eberly, B.; Person, D. A.

    1995-01-01

    OBJECTIVE--To test whether red and white wines are as potent as bismuth salicylate against the bacteria responsible for traveller's diarrhoea to try to explain wine's legendary reputation as a digestive aid. DESIGN--Red and white wine, bismuth salicylate, two solutions containing ethanol (diluted absolute ethanol and tequila), and sterilised water were tested against suspensions of salmonella, shigella, and Escherichia coli to determine relative antibacterial activity. Suspensions of 10(7) colony forming units of shigella, salmonella, and E coli were added to the test solutions and plated on standard nutrient agar at 0, 10, 20, 30, 60, and 120 minutes and 24 hours. Dilutions of wine and bismuth salicylate were then tested with E coli as the test bacterium, and the experiment repeated. MAIN OUTCOME MEASURES--Exposure times necessary for eradication of organisms for the different solutions; decreases in colony counts at the different exposure times for dilutions of wine and bismuth salicylates. RESULTS--Undiluted wine and bismuth salicylate were both effective in reducing the number of viable organisms (by 10(5)-10(6) colony forming units) after 20-30 minutes. Dilutions of wine were much more effective in decreasing colony counts than were similar dilutions of bismuth salicylate. CONCLUSION--The antibacterial property of wine is largely responsible for wine's reputation as a digestive aid. Images p1659-a PMID:8541747

  11. Polonium problem in lead-bismuth flow target

    Energy Technology Data Exchange (ETDEWEB)

    Pankratov, D.V.; Yefimov, E.I.; Bugreev, M.I. [State Scientific Centre of Russian Federation-Institute of Physics and Power Engineering, Obninsk (Russian Federation)

    1996-06-01

    Alpha-active polonium nuclides Po198 - Po210 are formed in a lead-bismuth target as results of reactions Bi{sup 209}(n,{gamma})Bi{sup 210} {yields} Po{sup 210}, Bi{sup 209}(p,xn)Po{sup 210} {yields} Po{sup 210 {minus} x} (x = 1-12), Pb{sup 208}({alpha},xn) {yields} Po{sup 210 {minus} x + 2} (x = 2-14). The most important nuclides are Po-210 (T{sub {1/2}}=138.4 day), Po-209 (T{sub {1/2}}=102 years) and Po-208 (T{sub {1/2}}=2.9 years). Polonium activity of the circuit for SINQ - conditions is about 15,000 Ci after 1-year operation. Polonium radiation hazard is connected with its output from the coolant and formation of aerosol and surface alpha-activity after the circuit break-down for repair works or in accidents. One of the important issues of polonium removal system creation is containing and storing polonium removed. Its storage in solidified alkaline is not expedient because of secondary neutron formation as a result of ({alpha},n) - reaction on oxygen and sodium nucleus. The estimations carried out demonstrated that by polonium concentration {approx} 100 Ci/l neutron current on the container surface can reach {approx} 10{sup 4}n/(cm{sup 2}s). Concentration and storage of polonium in solidified lead-bisumth seems the most convenient. The calculations demonstrated that in a 100 l container 50,000 Ci of polonium can be stored (as much as 3 times more than 1-year polonium product in SINQ-conditions) under temperature in the container less than melting point of lead bismuth (the wall temperature is about 100{degrees}C).

  12. Radiochemical Determination of Polonium in Liquid Metal Spallation Targets

    Science.gov (United States)

    Hammer, B.; Schumann, D.; Neuhausen, J.; Wohlmuther, M.; Türler, A.

    2014-05-01

    The MEGAPIE target, consisting of 82 litres of lead-bismuth eutectic (LBE), was irradiated close to the megawatt range (0.8 MW) from August to December 2006 in the SINQ facility at PSI. After a cooling period of 5 years, a post-irradiation examination (PIE) program was started and samples were taken from different positions in the target. In this paper we focus on the measurement of α-emitting 208-210Po in the MEGAPIE target. The experimental results are compared with theoretical predictions obtained by FLUKA and MCNPX calculations.

  13. Comparative study on solubilities of bismuth, bismuth oxide,and bismuth sulfide in hydrochloric acid-thiourea%铋、氧化铋、硫化铋在盐酸-硫脲中溶解性的比较研究

    Institute of Scientific and Technical Information of China (English)

    马哈亚·艾斯江; 巴哈尔古丽·别克吐尔逊

    2012-01-01

    在盐酸介质中及55℃加热条件下,铋与硫脲形成黄色络合物,从而建立了用分光光度法比较铋、氧化铋、硫化铋在盐酸-硫脲中溶解性的新方法.研究了反应介质、试剂浓度、加热时间、加热温度、震荡速率等因素的影响.在最佳实验条件下,溶液的质量浓度为0.04~0.24 mg/mL时符合比尔定律.相关系数R=0.999 9,检出限为1.05×10-2 μg/mL,标准偏差SD=0.003 5,相对标准偏差RSD=2.42%,摩尔吸收系数为1.515×105 L/(mol·cm),加标回收率为96.7%~98.8%.实验结果表明,铋、氧化铋、硫化铋的溶解性顺序大小为:铋>氧化铋>硫化铋.%A yellow complex is formed from bismuth and thiourea in hydrochloric acid under the heated condition of 55 °C. Thus a new method is set up to compare the solubilities of bismuth, bismuth oxide, and bismuth sulfide in hydrochloric acid-thiourea by using spectrophotometry.Effects of factors, such as reaction medium, reagent concentration, heating time, heating temperature, and oscillation speed,were studied respectively .Under the optimum experimental conditions, mass concentration of the solution is in line with Beer's law, when it is within the range of 0.04-0.24 mg/mL.The correlation coefficient (R) is 0.999 9.The detection limit is 1.05xl0-2μg/mL.The standard deviation is 0.003 5.The relative standard deviation (RSD) is 2.42%.The molar absorption coefficient is 1.515xl05 L/(mol-cm).The recovery rate of standard addition is at 96.7%~98.8%. Experimental result showed that the solubilities of bismuth,bismuth oxide,and bismuth sulfide in hydrochloric acid-thiourea is in order by size as following: Bi>Bi2O3>Bi2S3.

  14. Collective excitations and viscosity in liquid Bi

    Science.gov (United States)

    Ropo, Matti; Akola, Jaakko; Jones, R. O.

    2016-11-01

    The analysis of extensive density functional/molecular dynamics simulations (over 500 atoms, up to 100 ps) of liquid bismuth at four temperatures between 573 K and 1023 K has provided details of the dynamical structure factors, the dispersion of longitudinal and transverse collective modes, and related properties (power spectrum, viscosity, and sound velocity). Agreement with available inelastic x-ray and neutron scattering data and with previous simulations is generally very good. The results show that density functional/molecular dynamics simulations can give dynamical information of good quality without the use of fitting functions, even at long wavelengths.

  15. Thermodynamic assessment of solubility and activity of iron, chromium, and nickel in lead bismuth eutectic

    Science.gov (United States)

    Gossé, Stéphane

    2014-06-01

    Lead-Bismuth Eutectic (LBE) is a heavy liquid alloy used as a coolant for the Lead-Cooled Fast Reactors and spallation target for Accelerator Driven Systems. LBE is also considered in sodium fast reactor designs as coolant in secondary circuit to avoid any occurrence of the reaction between sodium and water in steam generators. Even if this coolant presents many advantages due to its thermophysical properties, corrosion towards structural materials remains one of the major issues of LBE. Because corrosion in LBE is partly driven by dissolution processes, the solubility and chemical activity of the main elements of the alloy are the key parameters to model the related corrosion processes. Using the Calphad method and the Thermo-Calc software, a thermodynamic database was developed to assess the interaction between Cr-Ni-Fe alloys and LBE. The current thermodynamic data on the Cr-Fe-Ni + Bi-Pb quinary system was reviewed and the Bi-Cr and Cr-Pb binary phase diagrams were assessed. Fe, Cr and Ni solubilities (in at. fraction, T in K) at LBE composition were calculated: Fe solubility at LBE composition: log10 (SFe)=0.5719-4398.6T (399-1173 K) Cr solubility at LBE composition: log10 (SCr)=-0.2757-3056.1T (399-1173 K) Ni solubility at LBE composition: log10 (SNi)=2.8717-2932.9T (528-742 K) log10 (SNi)=0.2871-1006.3T (742-1173 K) Then, the thermodynamic assessment performed in this study was used to predict more accurately the Fe, Cr and Ni activities and solubilities in the case of four austenitic model alloys also studied in the framework of corrosion tests [1]. The calculated activities and solubilities provide thermodynamic data to better understand dissolution or precipitation phenomena observed during LBE corrosion processes.

  16. Spectroscopic Characterization of Extracellular Polymeric Substances from Escherichia coli and Serratia marcescens: Suppression using Sub-Inhibitory Concentrations of Bismuth Thiols

    Energy Technology Data Exchange (ETDEWEB)

    Badireddy, Appala R.; Korpol, Bhoom Reddy; Chellam, Shankararaman; Gassman, Paul L.; Engelhard, Mark H.; Lea, Alan S.; Rosso, Kevin M.

    2008-10-21

    Free and capsular EPS produced by Escherichia coli and Serratia marcescens were characterized in detail using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and Auger electron spectroscopy (AES). Total EPS production decreased upon treatment with sub-inhibitory concentrations of lipophilic bismuth thiols (bismuth dimercaptopropanol, BisBAL; bismuth ethanedithiol, BisEDT; and bismuth pyrithione, BisPYR), BisBAL being most effective. Bismuth thiols also influenced acetylation and carboxylation of polysaccharides in EPS from S. marcescens. Extensive homology between EPS samples in the presence and absence of bismuth was observed with proteins, polysaccharides, and nucleic acids varying predominantly only in the total amount expressed. Second derivative analysis of the amide I region of FTIR spectra revealed decreases in protein secondary structures in the presence of bismuth thiols. Hence, anti-fouling properties of bismuth thiols appear to originate in their ability to suppress O-acetylation and protein secondary structures in addition to total EPS secretion.

  17. Sulfate-reducing bacteria slow intestinal transit in a bismuth-reversible fashion in mice.

    Science.gov (United States)

    Ritz, N L; Lin, D M; Wilson, M R; Barton, L L; Lin, H C

    2017-01-01

    Hydrogen sulfide (H2 S) serves as a mammalian cell-derived gaseous neurotransmitter. The intestines are exposed to a second source of this gas by sulfate-reducing bacteria (SRB). Bismuth subsalicylate binds H2 S rendering it insoluble. The aim of this study was to test the hypothesis that SRB may slow intestinal transit in a bismuth-reversible fashion. Eighty mice were randomized to five groups consisting of Live SRB, Killed SRB, SRB+Bismuth, Bismuth, and Saline. Desulfovibrio vulgaris, a common strain of SRB, was administered by gavage at the dose of 1.0 × 10(9) cells along with rhodamine, a fluorescent dye. Intestinal transit was measured 50 minutes after gavage by euthanizing the animals, removing the small intestine between the pyloric sphincter and the ileocecal valve and visualizing the distribution of rhodamine across the intestine using an imaging system (IVIS, Perkin-Elmer). Intestinal transit (n=50) was compared using geometric center (1=minimal movement, 100=maximal movement). H2 S concentration (n=30) was also measured when small intestinal luminal content was allowed to generate this gas. The Live SRB group had slower intestinal transit as represented by a geometric center score of 40.2 ± 5.7 when compared to Saline: 73.6 ± 5.7, Killed SRB: 77.9 ± 6.9, SRB+Bismuth: 81.0 ± 2.0, and Bismuth: 73.3 ± 4.2 (Pfashion in mice. Our results demonstrate that intestinal transit is slowed by SRB and this effect could be abolished by H2 S-binding bismuth. © 2016 John Wiley & Sons Ltd.

  18. Dextran coated bismuth-iron oxide nanohybrid contrast agents for computed tomography and magnetic resonance imaging.

    Science.gov (United States)

    Naha, Pratap C; Zaki, Ajlan Al; Hecht, Elizabeth; Chorny, Michael; Chhour, Peter; Blankemeyer, Eric; Yates, Douglas M; Witschey, Walter R T; Litt, Harold I; Tsourkas, Andrew; Cormode, David P

    2014-12-14

    Bismuth nanoparticles have been proposed as a novel CT contrast agent, however few syntheses of biocompatible bismuth nanoparticles have been achieved. We herein report the synthesis of composite bismuth-iron oxide nanoparticles (BION) that are based on a clinically approved, dextran-coated iron oxide formulation; the particles have the advantage of acting as contrast agents for both CT and MRI. BION were synthesized and characterized using various analytical methods. BION CT phantom images revealed that the X-ray attenuation of the different formulations was dependent upon the amount of bismuth present in the nanoparticle, while T2-weighted MRI contrast decreased with increasing bismuth content. No cytotoxicity was observed in Hep G2 and BJ5ta cells after 24 hours incubation with BION. The above properties, as well as the yield of synthesis and bismuth inclusion efficiency, led us to select the Bi-30 formulation for in vivo experiments, performed in mice using a micro-CT and a 9.4 T MRI system. X-ray contrast was observed in the heart and blood vessels over a 2 hour period, indicating that Bi-30 has a prolonged circulation half-life. Considerable signal loss in T2-weighted MR images was observed in the liver compared to pre-injection scans. Evaluation of the biodistribution of Bi-30 revealed that bismuth is excreted via the urine, with significant concentrations found in the kidneys and urine. In vitro experiments confirmed the degradability of Bi-30. In summary, dextran coated BION are biocompatible, biodegradable, possess strong X-ray attenuation properties and also can be used as T2-weighted MR contrast agents.

  19. Bismuth oxide aqueous colloidal nanoparticles inhibit Candida albicans growth and biofilm formation

    Directory of Open Access Journals (Sweden)

    Hernandez-Delgadillo R

    2013-04-01

    Full Text Available Rene Hernandez-Delgadillo,1 Donaji Velasco-Arias,3 Juan Jose Martinez-Sanmiguel,2 David Diaz,3 Inti Zumeta-Dube,3 Katiushka Arevalo-Niño,1 Claudio Cabral-Romero2 1Facultad de Ciencias Biológicas, Instituto de Biotecnologia, Universidad Autonoma de Nuevo Leon, UANL, Monterrey, Mexico; 2Facultad de Odontología, Universidad Autonoma de Nuevo Leon, UANL, Monterrey, México; 3Facultad de Quimica, Universidad Nacional Autonoma de Mexico, UNAM, Distrito Federal, México Abstract: Multiresistance among microorganisms to common antimicrobials has become one of the most significant concerns in modern medicine. Nanomaterials are a new alternative to successfully treat the multiresistant microorganisms. Nanostructured materials are used in many fields, including biological sciences and medicine. Recently, it was demonstrated that the bactericidal activity of zero-valent bismuth colloidal nanoparticles inhibited the growth of Streptococcus mutans; however the antimycotic potential of bismuth nanostructured derivatives has not yet been studied. The main objective of this investigation was to analyze the fungicidal activity of bismuth oxide nanoparticles against Candida albicans, and their antibiofilm capabilities. Our results showed that aqueous colloidal bismuth oxide nanoparticles displayed antimicrobial activity against C. albicans growth (reducing colony size by 85% and a complete inhibition of biofilm formation. These results are better than those obtained with chlorhexidine, nystatin, and terbinafine, the most effective oral antiseptic and commercial antifungal agents. In this work, we also compared the antimycotic activities of bulk bismuth oxide and bismuth nitrate, the precursor metallic salt. These results suggest that bismuth oxide colloidal nanoparticles could be a very interesting candidate as a fungicidal agent to be incorporated into an oral antiseptic. Additionally, we determined the minimum inhibitory concentration for the synthesized

  20. Zerovalent bismuth nanoparticles inhibit Streptococcus mutans growth and formation of biofilm

    Directory of Open Access Journals (Sweden)

    Hernandez-Delgadillo R

    2012-04-01

    Full Text Available Rene Hernandez-Delgadillo1, Donaji Velasco-Arias2, David Diaz2, Katiushka Arevalo-Niño1, Marianela Garza-Enriquez1, Myriam A De la Garza-Ramos1, Claudio Cabral-Romero11Instituto de Biotecnologia, Centro de Investigacion y Desarrollo en Ciencias de la Salud, CIDICS, Facultad de Odontologia, Universidad Autonoma de Nuevo Leon, UANL, Monterrey, Nuevo Leon, 2Facultad de Quimica, Universidad Nacional Autonoma de Mexico, Distrito Federal, MexicoBackground and methods: Despite continuous efforts, the increasing prevalence of resistance among pathogenic bacteria to common antibiotics has become one of the most significant concerns in modern medicine. Nanostructured materials are used in many fields, including biological sciences and medicine. While some bismuth derivatives has been used in medicine to treat vomiting, nausea, diarrhea, and stomach pain, the biocidal activity of zerovalent bismuth nanoparticles has not yet been studied. The objective of this investigation was to analyze the antimicrobial activity of bismuth nanoparticles against oral bacteria and their antibiofilm capabilities.Results: Our results showed that stable colloidal bismuth nanoparticles had 69% antimicrobial activity against Streptococcus mutans growth and achieved complete inhibition of biofilm formation. These results are similar to those obtained with chlorhexidine, the most commonly used oral antiseptic agent. The minimal inhibitory concentration of bismuth nanoparticles that interfered with S. mutans growth was 0.5 mM.Conclusion: These results suggest that zerovalent bismuth nanoparticles could be an interesting antimicrobial agent to be incorporated into an oral antiseptic preparation.Keywords: zerovalent bismuth nanoparticles, antimicrobial agent, biofilm, Streptococcus mutans

  1. POWER GENERATION FROM LIQUID METAL NUCLEAR FUEL

    Science.gov (United States)

    Dwyer, O.E.

    1958-12-23

    A nuclear reactor system is described wherein the reactor is the type using a liquid metal fuel, such as a dispersion of fissile material in bismuth. The reactor is designed ln the form of a closed loop having a core sectlon and heat exchanger sections. The liquid fuel is clrculated through the loop undergoing flssion in the core section to produce heat energy and transferrlng this heat energy to secondary fluids in the heat exchanger sections. The fission in the core may be produced by a separate neutron source or by a selfsustained chain reaction of the liquid fuel present in the core section. Additional auxiliary heat exchangers are used in the system to convert water into steam which drives a turbine.

  2. Design of an Actinide-Burning, Lead or Lead-Bismuth Cooled Reactor that Produces Low-Cost Electricity

    Energy Technology Data Exchange (ETDEWEB)

    Mac Donald, Philip Elsworth; Weaver, Kevan Dean; Davis, Cliff Bybee; MIT folks

    2000-07-01

    indirect cycle designs has investigated the effects of various parameters to increase electric production at full power. For the direct-contact reactor, major issues related to the direct-contact heat transfer rate and entrainment and carryover of liquid lead-bismuth to the turbine have been identified and analyzed. An economic analysis approach was also developed to determine the cost of electricity production in the lead-bismuth reactor. The approach will be formulated into a model and applied to develop scientific cost estimates for the different reactor designs and thus aid in the selection of the most economic option. In the area of lead-bismuth coolant activation, the radiological hazard was evaluated with particular emphasis on the direct-contact reactor. In this system, the lack of a physical barrier between the primary and secondary coolant favors the release of the alpha-emitter Po?210 and its transport throughout the plant. Modeling undertaken on the basis of the scarce information available in the literature confirmed the importance of this issue, as well as the need for experimental work to reduce the uncertainties on the basic characteristics of volatile polonium chemical forms.

  3. Development of oxygen sensors for use in liquid metal

    Energy Technology Data Exchange (ETDEWEB)

    Van Nieuwenhove, Rudi [Institutt for Energiteknikk, Halden, (Norway); Ejenstam, Jesper; Szakalos, Peter [KTH Royal Institute of Technology, Division of Surface and Corrosion Science, Stockholm, (Sweden)

    2015-07-01

    For generation IV reactor concepts, based on liquid metal cooling, there is a need for robust oxygen sensors which can be used in the core of the reactor since corrosion can only be kept sufficiently low by controlling the dissolved oxygen content in the liquid metal. A robust, ceramic membrane type sensor has been developed at IFE/Halden (Norway) and tested in an autoclave system at KTH (Sweden). The sensor has been tested in lead-bismuth at 550 deg. C and performed well. (authors)

  4. Simple counting technique for measuring mixtures of two pure beta-emitting radionuclides

    CSIR Research Space (South Africa)

    Van Wyngaardt, WM

    2006-08-01

    Full Text Available A simple counting technique to measure mixtures of two pure beta-emitting radionuclides is described. The method is based on elements of two liquid scintillation techniques that are widely used to measure single-radionuclide solutions, namely...

  5. Bismuth Modified Carbon-Based Electrodes for the Determination of Selected Neonicotinoid Insecticides

    Directory of Open Access Journals (Sweden)

    Marko Rodić

    2011-05-01

    Full Text Available Two types of bismuth modified electrodes, a bismuth-film modified glassy carbon (BiF-GCE and a bismuth bulk modified carbon paste, were applied for the determination of selected nitroguanidine neonicotinoid insecticides. The method based on an ex situ prepared BiF-GCE operated in the differential pulse voltammetric (DPV mode was applied to determine clothianidin in the concentration range from 2.5 to 23 μg cm−3 with a relative standard deviation (RSD not exceeding 1.5%. The tricresyl phosphate-based carbon paste electrodes (TCP-CPEs, bulk modified with 5 and 20 w/w% of bismuth, showed a different analytical performance in the determination of imidacloprid, regarding the peak shape, potential window, and noise level. The TCP-CPE with 5% Bi was advantageous, and the developed DPV method based on it allowed the determination in the concentration range from 1.7 to 60 μg cm−3 with an RSD of 2.4%. To get a deeper insight into the morphology of the bismuth-based sensor surfaces, scanning electron microscopic measurements were performed of both the surface film and the bulk modified electrodes.

  6. Facile solvothermal synthesis of a graphene nanosheet-bismuth oxide composite and its electrochemical characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Wang Huanwen [Key Laboratory of Eco-Environment-Related Polymer Materials of Ministry of Education, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070 (China); Hu Zhongai, E-mail: zhongai@nwnu.edu.c [Key Laboratory of Eco-Environment-Related Polymer Materials of Ministry of Education, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070 (China); Chang Yanqin; Chen Yanli; Lei Ziqiang; Zhang Ziyu; Yang Yuying [Key Laboratory of Eco-Environment-Related Polymer Materials of Ministry of Education, Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070 (China)

    2010-12-01

    This work demonstrates a novel and facile route for preparing graphene-based composites comprising of metal oxide nanoparticles and graphene. A graphene nanosheet-bismuth oxide composite as electrode materials of supercapacitors was firstly synthesized by thermally treating the graphene-bismuth composite, which was obtained through simultaneous solvothermal reduction of the colloidal dispersions of negatively charged graphene oxide sheets in N,N-dimethyl formamide (DMF) solution of bismuth cations at 180 {sup o}C. The morphology, composition, and microstructure of the composites together with pure graphite oxide, and graphene were characterized using powder X-ray diffraction (XRD), FT-IR, field emission scanning electron microscopy (FESEM), transmission electron microscope (TEM), thermogravimetry and differential thermogravimetry (TG-DTG). The electrochemical behaviors were measured by cyclic voltammogram (CV), galvanostatic charge-discharge and electrochemical impedance spectroscopy (EIS). The specific capacitance of 255 F g{sup -1} (based on composite) is obtained at a specific current of 1 A g{sup -1} as compared with 71 F g{sup -1} for pure graphene. The loaded-bismuth oxide achieves a specific capacitance as high as 757 F g{sup -1} even at 10 A g{sup -1}. In addition, the graphene nanosheet-bismuth oxide composite electrode exhibits the excellent rate capability and well reversibility.

  7. Synthesis and performance of bismuth trioxide nanoparticles for high energy gas generator use.

    Science.gov (United States)

    Martirosyan, K S; Wang, L; Vicent, A; Luss, D

    2009-10-01

    Our experiments showed that the combustion of an Al-Bi2O3 nanoparticle mixture generated the highest pressure pulse among common nanothermite reactions and can potentially be used as a nanoenergetic gas generator. The combustion front propagation velocity and rate of energy release increased by up to three orders of magnitude when the particle size was reduced to a nanosize range for both the aluminum and the oxidizer. We developed a novel one-step (metal nitrate-glycine) combustion synthesis of nanostructured amorphous-like and highly crystalline bismuth trioxide nanoparticles. The combustion synthesis was conducted using a solution of molten bismuth nitrate as an oxidizer and glycine as a fuel. The glycine was completely combusted during the thermal decomposition of the bismuth nitrate pentahydrate and generated a temperature front that propagated through the sample. Increasing the fuel concentration increased the maximum combustion temperature from 280 to 1200 degrees C and the Bi2O3 particle size from 20 to 100 nm. The oxidizer/fuel ratio had a strong impact on the bismuth trioxide particle crystallinity. At low temperature (280 degrees C), amorphous-like bismuth trioxide nanoparticles formed, while at T > or =370 degrees C the structures were crystalline. A peak pressure of approximately 12 MPa and a thermal front propagating velocity of approximately 2500 m s(-1) were achieved during the combustion of an Al-Bi2O3 mixture containing 80 wt% of the synthesized Bi2O3 crystalline nanoparticles (size: 40-50 nm).

  8. How reliable are environmental data on 'orphan' elements? The case of bismuth concentrations in surface waters.

    Science.gov (United States)

    Filella, Montserrat

    2010-01-01

    Like all elements of the periodic table, bismuth is ubiquitously distributed throughout the environment as a result of natural processes and human activities. It is present as Bi(III) in environmental, biological and geochemical samples. Although bismuth and its compounds are considered to be non-toxic to humans, its increasing use as a replacement for lead has highlighted how little is known about its environmental and ecotoxicological behaviour. In this first critical review paper on the existing information on bismuth occurrence in natural waters, 125 papers on fresh and marine waters have been collated. Although the initial objective of this study was to establish the range of the typical concentrations of total dissolved bismuth in natural waters, this proved impossible to achieve due to the wide, and hitherto unexplained, dispersion of published data. Since analytical limitations might be one of the reasons underlying value dispersion, new analytical methods published since 2000--intended to be applied to natural waters--have also been reviewed. Disappointingly, the detection limits of the bulk of them are well above those required; they are thus of limited usefulness. Analysis of the existing information on bismuth in secondary references (i.e., books, review chapters) and on its chemical speciation in seawater revealed that the uncritical reproduction of old data is a widespread practice.

  9. Hierarchical Non-Emitting Markov Models

    CERN Document Server

    Ristad, E S; Ristad, Eric Sven; Thomas, Robert G.

    1998-01-01

    We describe a simple variant of the interpolated Markov model with non-emitting state transitions and prove that it is strictly more powerful than any Markov model. More importantly, the non-emitting model outperforms the classic interpolated model on the natural language texts under a wide range of experimental conditions, with only a modest increase in computational requirements. The non-emitting model is also much less prone to overfitting. Keywords: Markov model, interpolated Markov model, hidden Markov model, mixture modeling, non-emitting state transitions, state-conditional interpolation, statistical language model, discrete time series, Brown corpus, Wall Street Journal.

  10. Light-Emitting Devices with Conjugated Polymers

    Directory of Open Access Journals (Sweden)

    Xian-Yu Deng

    2011-03-01

    Full Text Available This article introduces a previous study and tremendous progress in basic theoretical modeling, material developments and device engineering for polymer light-emitting devices (PLEDs.

  11. The influence of metronidazole resistance on the efficacy of ranitidine bismuth citrate triple therapy regimens for Helicobacter pylori infection

    NARCIS (Netherlands)

    Van der Wouden, EJ; Thijs, JC; Van Zwet, AA; Kooy, A; Kleibeuker, JH

    Aim: To assess the influence of metronidazole resistance on the efficacy of ranitidine bismuth citrate-based triple therapy regimens in two consecutive studies. Methods: In the first study, patients with a culture-proven Helicobacter pylori infection were treated with ranitidine bismuth citrate 400

  12. Computational chemistry calculations of stability for bismuth nanotubes, fullerene-like structures and hydrogen-containing nanostructures.

    Science.gov (United States)

    Kharissova, Oxana V; Osorio, Mario; Vázquez, Mario Sánchez; Kharisov, Boris I

    2012-08-01

    Using molecular mechanics (MM+), semi-empirical (PM6) and density functional theory (DFT) (B3LYP) methods we characterized bismuth nanotubes. In addition, we predicted the bismuth clusters {Bi(20)(C(5V)), Bi(24)(C(6v)), Bi(28)(C(1)), B(32)(D(3H)), Bi(60)(C(I))} and calculated their conductor properties.

  13. Magnetic and Electrical Characteristics of Bismuth Ferrite, Depending on the Impurities, Method of Preparation and Size of the Nanoparticles

    Directory of Open Access Journals (Sweden)

    V.M. Sarnatsky

    2016-10-01

    Full Text Available The prospect of application of the multiferroics in devices and spintronics devices is shown. A comparative analysis of magnetic and dielectric properties of nanostructures based on bismuth ferrite which were synthesized by various ways was made. The results of studies of the structure and properties of the nanostructured bismuth ferrite powder, synthesized by combustion of nitrate - organic precursors, are presented.

  14. Development of novel UV emitting single crystalline film scintillators

    Science.gov (United States)

    Zorenko, Yu; Gorbenko, V.; Savchyn, V.; Voznyak, T.; Nikl, M.; Mares, J. A.; Martin, T.; Douissard, P.-A.

    2011-04-01

    The work is dedicated to development of new types of UV -emitting scintillators based on single crystalline films (SCF) of aluminimum perovskites and garnets grown by the liquid phase epitaxy (LPE) method. The development of the following three types of UV SCF scintillators is considered in this work: i) Ce-doped SCF of Y-Lu-Al-perovskites with Ce3+ emission in the 360-370 nm range with a decay time of 16-17 ns; ii) Pr-doped SCF of Y-Lu-Al garnets with Pr3+ emission in the 300-400 nm range with a decay time of 13-17 ns; iii) La3+ and Sc3+ doped SCF of Y-Lu-Al-garnets, emitting in the 290-400 nm range due to formation of the LaY,Lu, ScY,Lu and ScAl centers with decay time of 250-575 ns. The results of testing the several novel UV-emitting SCFs scintillators for visualization of X-ray images at ESFR are presented. It is shown that the UV emission of the LuAG:Sc, LuAG:La and LuAG:Pr SCFs is efficient enough for conversion of X-ray to the UV light and that these scintillators can be used for improvement of the resolution of imaging detectors in synchrotron radiation applications.

  15. Stable high conductivity ceria/bismuth oxide bilayered electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Wachsman, E.D.; Jayaweera, P.; Jiang, N.; Lowe, D.M.; Pound, B.G. [SRI international, Menlo Park, CA (United States). Materials Research Center

    1997-01-01

    The authors have developed a high conductivity bilayered ceria/bismuth oxide anolyte/electrolyte that uses the Po{sub 2} gradient to obtain stability at the anolyte-electrolyte interface and reduced electronic conduction due to the electrolyte region. Results in terms of solid oxide fuel cell (SOFC) performance and stability are presented. These results include a 90 to 160 mV increase in open-circuit potential, depending on temperature, with the bilayered structure as compared to SOFCs fabricated from a single ceria layer. An open-circuit potential of >1.0 V was obtained at 500 C with the bilayered structure. This increase in open-circuit potential is obtained without any measurable increase in cell resistance and is stable for over 1,400 h of testing, under both open-circuit and maximum power conditions. Moreover, SOFCs fabricated from the bilayered structure result in a 33% greater power density as compared to cells with a single ceria electrolyte layer.

  16. Ferroelectric and photocatalytic behavior of bismuth ferrite nano wire

    Energy Technology Data Exchange (ETDEWEB)

    William, R. V.; Marikani, A., E-mail: amari@mepcoeng.ac.in [Department of Physics, Mepco Schlenk Engineering College, Sivakasi – 626 005, Tamil Nadu (India); Madhavan, D. [Department of Chemistry, Mepco Schlenk Engineering College, Sivakasi – 626 005, Tamil Nadu (India)

    2016-05-23

    Multiferroic bismuth ferrite nanowires are prepared through polyol method with an average diameter of 35 nm with a narrow size distribution. The band gap was determined to be 2.10 eV, indicating their potential application as visible-light-response photo catalyst. The magnificent photocatalytic behaviors of BiFeO{sub 3} nanowires are understood from the methyl violet degradation under visible light irradiation. Moreover, the nano-wire takes only a lesser time for the diffusion of electron-hole pair from the surface of the sample. Further the BiFeO{sub 3} nano-wire was characterized using XRD, SEM, and U-V. The ferroelectric studies of BiFeO{sub 3} nano-wire show a frequency dependent property and maximum coercivity of 2.7 V/cm were achieved with a remanent polarization at 0.5 µC/cm{sup 2} at the frequency 4 kHz. The coercivity of BiFeO{sub 3} nano wire changes with variation of frequency from 1 kHz to 4 kHz.

  17. Closing uranyl polyoxometalate capsules with bismuth and lead polyoxocations

    Energy Technology Data Exchange (ETDEWEB)

    Renier, Olivier; Falaise, Clement; Neal, Harrison; Kozma, Karoly; Nyman, May [Oregon State Univ., Corvallis, OR (United States). Dept. of Chemistry

    2016-10-17

    Uranyl polyoxometalate clusters are both fundamentally fascinating and potentially relevant to nuclear energy applications. With only ten years of development, there is still much to be discovered about heterometal derivatives and aqueous speciation and behavior. Herein, we show that it is possible to encapsulate the polyoxocations [Bi{sub 6}O{sub 8}]{sup 2+} and [Pb{sub 8}O{sub 6}]{sup 4+} in [(UO{sub 2})(O{sub 2})(OH)]{sub 24}{sup 24-} (denoted Bi rate at U{sub 24} and Pb rate at U{sub 24}) in pure form and high yields despite the fact that under aqueous conditions, these compounds are stable on opposite ends of the pH scale. Moreover, [Pb{sub 8}O{sub 6}]{sup 4+} is a formerly unknown Pb{sup II} polynuclear species, both in solution and in the solid state. Raman spectroscopic and mass spectrometric analysis of the reaction solutions revealed the very rapid assembly of the nested clusters, driven by bismuth- or lead-promoted decomposition of excess peroxide, which inhibits U{sub 24} formation. Experimental and simulated small-angle X-ray scattering data of Bi rate at U{sub 24} and Pb rate at U{sub 24} solutions revealed that this technique is very sensitive not only to the size and shape of the clusters, but also to the encapsulated species.

  18. Energy levels scheme simulation of divalent cobalt doped bismuth germanate

    Energy Technology Data Exchange (ETDEWEB)

    Andreici, Emiliana-Laura, E-mail: andreicilaura@yahoo.com [Department of Physics, West University of Timisoara, Bd. V. Parvan 4,300223 Timisoara (Romania); Petkova, Petya [Shumen University “Konstantin Preslavsky”, 115 Universitetska street, 9712 Shumen (Bulgaria); Avram, Nicolae M. [Department of Physics, West University of Timisoara, Bd. V. Parvan 4,300223 Timisoara (Romania); Academy of Romanian Scientists, Independentei 54, 050094-Bucharest (Romania)

    2015-12-07

    The aim of this paper is to simulate the energy levels scheme for Bismuth Germanate (BGO) doped with divalent cobalt, in order to give a reliable explanation for spectral experimental data. In the semiempirical crystal field theory we first modeled the Crystal Field Parameters (CFPs) of BGO:Cr{sup 2+} system, in the frame of Exchange Charge Model (ECM), with actually site symmetry of the impurity ions after doping. The values of CFPs depend on the geometry of doped host matrix and by parameter G of ECM. First, we optimized the geometry of undoped BGO host matrix and afterwards, that of doped BGO with divalent cobalt. The charges effect of ligands and covalence bonding between cobalt cations and oxygen anions, in the cluster approach, also were taken into account. With the obtained values of the CFPs we simulate the energy levels scheme of cobalt ions, by diagonalizing the matrix of the doped crystal Hamiltonian. Obviously, energy levels and estimated Racah parameters B and C were compared with the experimental spectroscopic data and discussed. Comparison of obtained results with experimental data shows quite satisfactory, which justify the model and simulation schemes used for the title system.

  19. Bismuth nanoparticles integration into heavy metal electrochemical stripping sensor.

    Science.gov (United States)

    Cadevall, Miquel; Ros, Josep; Merkoçi, Arben

    2015-08-01

    Between their many applications bismuth nanoparticles (BiNPs) are showing interest as pre-concentrators in heavy metals detection while being applied as working electrode modifiers used in electrochemical stripping analysis. From the different reported methods to synthesize BiNPs we are focused on the typical polyol method, largely used in these types of metallic and semi-metallic nanoparticles. This study presents the strategy for an easy control of the shape and size of BiNPs including nanocubes, nanosferes and triangular nanostructures. To improve the BiNP size and shape, different reducing agents (ethylene glycol or sodium hypophosphite) and stabilizers (polyvinyl pyrrolidone, PVP, in different amounts) have been studied. The efficiency of BiNPs for heavy metals analysis in terms of detection sensitivity while being used as modifiers of screen-printed carbon electrodes including the applicability of the developed device in real sea water samples is shown. A parallel study between the obtained nanoparticles and their performance in heavy metal sensing has been described in this communication.

  20. Pressure effects on crystal and electronic structure of bismuth tellurohalides

    Science.gov (United States)

    Rusinov, I. P.; Menshchikova, T. V.; Sklyadneva, I. Yu; Heid, R.; Bohnen, K.-P.; Chulkov, E. V.

    2016-11-01

    We study the possibility of pressure-induced transitions from a normal semiconductor to a topological insulator (TI) in bismuth tellurohalides using density functional theory and tight-binding method. In BiTeI this transition is realized through the formation of an intermediate phase, a Weyl semimetal, that leads to modification of surface state dispersions. In the topologically trivial phase, the surface states exhibit a Bychkov-Rashba type dispersion. The Weyl semimetal phase exists in a narrow pressure interval of 0.2 GPa. After the Weyl semimetal-TI transition occurs, the surface electronic structure is characterized by gapless states with linear dispersion. The peculiarities of the surface states modification under pressure depend on the band-bending effect. We have also calculated the frequencies of Raman active modes for BiTeI in the proposed high-pressure crystal phases in order to compare them with available experimental data. Unlike BiTeI, in BiTeBr and BiTeCl the topological phase transition does not occur. In BiTeBr, the crystal structure changes with pressure but the phase remains a trivial one. However, the transition appears to be possible if the low-pressure crystal structure is retained. In BiTeCl under pressure, the topological phase does not appear up to 18 GPa due to a relatively large band gap width in this compound.

  1. Optical analysis of samarium doped sodium bismuth silicate glass

    Science.gov (United States)

    Thomas, V.; Sofin, R. G. S.; Allen, M.; Thomas, H.; Biju, P. R.; Jose, G.; Unnikrishnan, N. V.

    2017-01-01

    Samarium doped sodium bismuth silicate glass was synthesized using the melt quenching method. Detailed optical spectroscopic studies of the glassy material were carried out in the UV-Vis-NIR spectral range. Using the optical absorption spectra Judd-Ofelt (JO) parameters are derived. The calculated values of the JO parameters are utilized in evaluating the various radiative parameters such as electric dipole line strengths (Sed), radiative transition probabilities (Arad), radiative lifetimes (τrad), fluorescence branching ratios (β) and the integrated absorption cross- sections (σa) for stimulated emission from various excited states of Sm3 +‡ ion. The principal fluorescence transitions are identified by recording the fluorescence spectrum. Our analysis revealed that the novel glassy system has the optimum values for the key parameters viz. spectroscopic quality factor, optical gain, stimulated emission cross section and quantum efficiency, which are required for a high performance optical amplifier. Calculated chromaticity co-ordinates (0.61, 0.38) also confirm its application potential in display devices.

  2. Thermoelectric characterization of individual bismuth selenide topological insulator nanoribbons

    Science.gov (United States)

    Tang, Hao; Wang, Xiaomeng; Xiong, Yucheng; Zhao, Yang; Zhang, Yin; Zhang, Yan; Yang, Juekuan; Xu, Dongyan

    2015-04-01

    Bismuth selenide (Bi2Se3) nanoribbons have attracted tremendous research interest recently to study the properties of topologically protected surface states that enable new opportunities to enhance the thermoelectric performance. However, the thermoelectric characterization of individual Bi2Se3 nanoribbons is rare due to the technological challenges in the measurements. One challenge is to ensure good contacts between the nanoribbon and electrodes in order to determine the thermal and electrical properties accurately. In this work, we report the thermoelectric characterization of individual Bi2Se3 nanoribbons via a suspended microdevice method. Through careful measurements, we have demonstrated that contact thermal resistance is negligible after the electron-beam-induced deposition (EBID) of platinum/carbon (Pt/C) composites at the contacts between the nanoribbon and electrodes. It is shown that the thermal conductivity of the Bi2Se3 nanoribbons is less than 50% of the bulk value over the whole measurement temperature range, which can be attributed to enhanced phonon boundary scattering. Our results indicate that intrinsic Bi2Se3 nanoribbons prepared in this work are highly doped n-type semiconductors, and therefore the Fermi level should be in the conduction band and no topological transport behavior can be observed in the intrinsic system.

  3. Antibacterial effect of bismuth subsalicylate nanoparticles synthesized by laser ablation

    Energy Technology Data Exchange (ETDEWEB)

    Flores-Castañeda, Mariela [Instituto Nacional de Investigaciones Nucleares (Mexico); Vega-Jiménez, Alejandro L., E-mail: argelia.almaguer@mac.com; Almaguer-Flores, Argelia [Universidad Nacional Autónoma de México, Facultad de Odontología, DEPeI, I (Mexico); Camps, Enrique; Pérez, Mario [Instituto Nacional de Investigaciones Nucleares (Mexico); Silva-Bermudez, Phaedra [Instituto Nacional de Rehabilitación, Unidad de Ingeniería de Tejidos, Terapia Celular y Medicina Regenerativa (Mexico); Berea, Edgardo [FarmaQuimia SA de CV. (Mexico); Rodil, Sandra E. [Universidad Nacional Autónoma de México, Instituto de Investigaciones en Materiales (Mexico)

    2015-11-15

    The antimicrobial properties of bismuth subsalicylate (BSS) nanoparticles against four opportunistic pathogens; E. coli, P. aeruginosa, S. aureus, and S. epidermidis were determined. BSS nanoparticles were synthesized by pulse laser ablation of a solid target in distilled water under different conditions. The nanoparticles were characterized using high-resolution transmission electron microscopy and absorption spectra and small angle X-ray scattering. The analysis shows that the colloids maintained the BSS structure and presented average particle size between 20 and 60 nm, while the concentration ranges from 95 to 195 mg/L. The antibacterial effect was reported as the inhibition ratio of the bacterial growth after 24 h and the cell viability was measured using the XTT assay. The results showed that the inhibition ratio of E. coli and S. epidermidis was dependant on the NPs size and/or concentration, meanwhile P. aeruginosa and S. aureus were more sensitive to the BSS nanoparticles independently of both the size and the concentration. In general, the BSS colloids with average particle size of 20 nm were the most effective, attaining inhibition ratios >80 %, similar or larger than those obtained with the antibiotic used as control. The results suggest that the BSS colloids could be used as effective antibacterial agents with potential applications in the medical area.

  4. Shape-dependent photocatalytic activities of bismuth subcarbonate nanostructures.

    Science.gov (United States)

    Tang, Jiale; Cheng, Gang; Zhou, Huamin; Yang, Hao; Lu, Zhong; Chen, Rong

    2012-05-01

    Different shaped bismuth subcarbonate ((BiO)2CO3) nanostructures including irregular nanoplates, relatively uniform nanoplates and nanocubes were prepared and characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-vis diffuse reflection spectroscopy (DRS) and nitrogen adsorption. The photocatalytic performance of the as-synthesized (BiO)2CO3 nanostructures on the degradation of Rhodamine B (RhB), methyl orange (MO) and methyl blue (MB) were evaluated under UV-vis light irradiation (modeling sunlight). The photocatalysis tests showed that all the different (BiO)2CO3 nanostructures displayed enhanced photodegradation performance compared with commercial (BiO)2CO3. The irregular (BiO)2CO3 nanoplates exhibited the highest photocatalytic activity on the degradation of different organic dyes. (BiO)2CO3 nanosturctures exhibited the different capacity to bleach the three organic dyes, which might be attributed to their different molecular structures. This work may provide a potential photocatalyst for the environmental pollutants treatments.

  5. Dielectric and Impedance Spectroscopy of Barium Bismuth Vanadate Ferroelectrics

    Science.gov (United States)

    Sutar, B. C.; Choudhary, R. N. P.; Das, Piyush R.

    2014-07-01

    Structural, micro-structural and electrical properties of barium bismuth vanadate Ba(Bi0.5V0.5)O3 ceramics were investigated. X-ray diffraction (XRD) analysis of the prepared material confirmed the formation of the compound with monoclinic crystal system. Scanning electron microscopy (SEM) of the compound exhibits well-defined grains that are uniformly distributed throughout the surface of the sample. Dielectric properties of the compound were studied as a function of temperature at different frequencies. An observation of dielectric anomaly at 295 °C is due to ferroelectric phase transition that was later confirmed by the appearance of hysteresis loop. Detailed studies of complex impedance spectroscopy have provided a better understanding of the relaxation process and correlations between the microstructure-electrical properties of the materials. The nature of frequency dependence of ac conductivity obeys the Debye power law. The dc conductivity, calculated from the ac conductivity spectrum, shows the negative temperature coefficient of resistance behavior similar to that of a semiconductor.

  6. Mechanically Activated Synthesis of Nanocrystalline Powders of Ferroelectric Bismuth Vanadate

    Science.gov (United States)

    Shantha, K.; Subbanna, G. N.; Varma, K. B. R.

    1999-01-01

    Mechanical milling of a stoichiometric mixture of Bi2O3and V2O5yielded nanosized powders of bismuth vanadate, Bi2VO5.5(BiV). Structural evolution of the desired BiV phase, through an intermediate product (BiVO4), was monitored by subjecting the powders, ball milled for various durations to X-ray powder diffraction (XRD), differential thermal analysis (DTA), and transmission electron microscopic (TEM) studies. XRD studies indicate that the relative amount of the BiV phase present in the ball-milled mixture increases with increase in milling time and its formation reaches completion within 54 h of milling. Assynthesized powders were found to stabilize in the high-temperature tetragonal (γ) phase. DTA analyses of the powders milled for various durations suggest that the BiV phase-formation temperature decreases with increase in milling time. The nanometric size (30 nm) of the crystallites in the final product was confirmed by TEM and XRD studies. TEM studies clearly demonstrate the growth of BiV onBi2O3crystallites.

  7. One-dimensional Topological Edge States of Bismuth Bilayers

    Science.gov (United States)

    Drozdov, Ilya; Alexandradinata, Aris; Jeon, Sangjun; Nadj-Perge, Stevan; Ji, Huiwen; Cava, Robert; Bernevig, B. Andrei; Yazdani, Ali

    2014-03-01

    The hallmark of a time-reversal symmetry protected topologically insulating state of matter in two-dimensions (2D) is the existence of chiral edge modes propagating along the perimeter of the sample. Bilayers of bismuth (Bi), an elemental system theoretically predicted to be a Quantum Spin Hall (QSH) insulator1, has been studied with Scanning Tunneling Microscopy (STM) and the electronic structure of its bulk and edge modes has been experimentally investigated. Spectroscopic mapping with STM reveals the presence of the state bound to the edges of the Bi-bilayer. By visualizing quantum interference of the edge state quasi-particles in confined geometries we characterize their dispersion and demonstrate that their properties are consistent with the absence of backscattering. Hybridization of the edge modes to the underlying substrate will be discussed. [1] Shuichi Murakami, Phys. Rev. Lett. 97, 236805 (2006). The work at Princeton and the Princeton Nanoscale Microscopy Laboratory was supported by ARO MURI program W911NF-12-1-0461, DARPA-SPWAR Meso program N6601-11-1-4110, NSF-DMR1104612, and NSF-MRSEC programs through the Princeton Center for Complex Materials (DMR-0819860)

  8. Process dependent thermoelectric properties of EDTA assisted bismuth telluride

    Energy Technology Data Exchange (ETDEWEB)

    Kulsi, Chiranjit; Banerjee, Dipali, E-mail: dipalibanerjeebesu@gmail.com [Department of Physics, Indian Institute of Engineering Science and Technology, Shibpur, Howrah-711103, West Bengal (India); Kargupta, Kajari [Chemical Engineering Department, Jadavpur University, Kolkata-700032, West Bengal (India)

    2016-04-13

    Comparison between the structure and thermoelectric properties of EDTA (Ethylene-diamine-tetra-acetic acid) assisted bismuth telluride prepared by electrochemical deposition and hydrothermal route is reported in the present work. The prepared samples have been structurally characterized by high resolution X-ray diffraction spectra (HRXRD), field emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopic images (HRTEM). Crystallite size and strain have been determined from Williamson-Hall plot of XRD which is in conformity with TEM images. Measurement of transport properties show sample in the pellet form (S{sub 1}) prepared via hydrothermal route has higher value of thermoelectric power (S) than the electrodeposited film (S{sub 2}). But due to a substantial increase in the electrical conductivity (σ) of the film (S{sub 2}) over the pellet (S{sub 1}), the power factor and the figure of merit is higher for sample S{sub 2} than the sample S{sub 1} at room temperature.

  9. Synthesis and characterization of bismuth zinc niobate pyrochlore nanopowders

    Directory of Open Access Journals (Sweden)

    Sonia Maria Zanetti

    2007-09-01

    Full Text Available Bismuth zinc niobate pyrochlores Bi1.5ZnNb1.5O7 (alpha-BZN, and Bi2(Zn1/3Nb2/32O 7 (beta-BZN have been synthesized by chemical method based on the polymeric precursors. The pyrochlore phase was investigated by differential scanning calorimetry, infrared spectroscopy, and X ray diffraction. Powder and sintered pellets morphology was examined by scanning electron microscopy. The study of alpha-BZN phase formation reveals that, at 500 °C, the pyrochlore phase was already present while a single-phased nanopowder was obtained after calcination at 700 °C. The crystallization mechanism of the beta-BZN is quite different, occurring through the crystallization of alpha-BZN and BiNbO4 intermediary phases. Both compositions yielded soft agglomerated powders. alpha-BZN pellets, sintered at 800 °C for 2 hours, presented a relative density of 97.3% while those of beta-BZN, sintered at 900 °C for 2 hours, reached only 91.8%. Dielectric constant and dielectric loss, measured at 1 MHz, were 150 and 4 x/10-4 for a-BZN, and 97 and 8 x 10-4 for beta-BZN.

  10. Aromatic amino acids in high selectivity bismuth(III) recognition.

    Science.gov (United States)

    Ghatak, Sumanta Kumar; Dey, Debarati; Sen, Souvik; Sen, Kamalika

    2013-04-21

    The three aromatic amino acids, tyrosine, tryptophan and phenylalanine, play different physiological roles in life processes. Metal ions capable of binding these amino acids may aid in the reduction of effective concentration of these amino acids in any physiological system. Here we have studied the efficacy of some heavy metals for their complexation with these three amino acids. Bismuth has been found to bind selectively with these aromatic amino acids and this was confirmed using spectrofluorimetric, spectrophotometric and cyclic voltammetric studies. The series of heavy metals has been chosen because each of these metals remains associated with the others at very low concentration levels and Bi(III) is the least toxic amongst the other elements. So, selective recognition for Bi(III) would also mean no response for the other heavy elements if contaminants are present even at low concentration levels. The affinity towards these amino acids has been found to be in the order tryptophan phenylalanine amino acids have been calculated using Benesi-Hildebrand equations and the corresponding free energy change has also been calculated. The values of the association constants obtained from BH equations using absorbance values corroborate with the Stern-Volmer constants obtained from fluorimetric studies. The evidence for complexation is also supported by the results of cyclic voltammetry.

  11. Bismuth alloying properties in GaAs nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Ding, Lu [State Key Laboratory of Information Photonics and Optical Communications, Ministry of Education, Beijing University of Posts and Telecommunications, PO Box 72, Beijing 100876 (China); Lu, Pengfei, E-mail: photon.bupt@gmail.com [State Key Laboratory of Information Photonics and Optical Communications, Ministry of Education, Beijing University of Posts and Telecommunications, PO Box 72, Beijing 100876 (China); Cao, Huawei; Cai, Ningning; Yu, Zhongyuan [State Key Laboratory of Information Photonics and Optical Communications, Ministry of Education, Beijing University of Posts and Telecommunications, PO Box 72, Beijing 100876 (China); Gao, Tao [Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065 (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)

    2013-09-15

    First-principles calculations have been performed to investigate the structural, electronic and optical properties of bismuth alloying in GaAs nanowires. A typical model of Ga{sub 31}As{sub 31} nanowires is introduced for its reasonable band gap. The band gap of GaAs{sub 1−x}Bi{sub x} shrinks clearly with the increasing Bi concentration and the band edge shifts when spin–orbit coupling (SOC) is considered. The insertion of Bi atom leads to hybridization of Ga/As/Bi p states which contributes a lot around Fermi level. Scissor effect is involved. The optical properties are presented, including dielectric function, optical absorption spectra and reflectivity, which are also varied with the increasing of Bi concentrations. - Graphical abstract: Top view of Bi-doped GaAs nanowires. Ga, As, and Bi atoms are denoted with grey, purple and red balls, respectively. Display Omitted - Highlights: • A typical model of Ga{sub 31}As{sub 31} nanowires is introduced for its reasonable band gap. • The band gap of GaAs{sub 1−x}Bi{sub x} shrinks clearly with the increasing Bi concentration. • The band edge shifts when spin–orbit coupling (SOC) is considered. • The insertion of Bi atom leads to hybridization of Ga/As/Bi p states.

  12. Insights into the growth of bismuth nanoparticles on 2D structured BiOCl photocatalysts: an in situ TEM investigation.

    Science.gov (United States)

    Chang, Xiaofeng; Wang, Shuangbao; Qi, Qi; Gondal, Mohammed A; Rashid, Siddique G; Gao, Si; Yang, Deyuan; Shen, Kai; Xu, Qingyu; Wang, Peng

    2015-09-28

    The synthetic techniques for novel photocatalytic crystals had evolved by a trial-and-error process that spanned more than two decades, and an insight into the photocatalytic crystal growth process is a challenging area and prerequisite for achieving an excellent photoactivity. Bismuth nanoparticle based hybrids, such as Bi/BiOCl composites, have recently been investigated as highly efficient photocatalytic systems because of the localized surface plasmon resonance (LSPR) of nanostructured bismuth. In this work, the observation towards the formation and growth of bismuth nanoparticles onto 2D structured BiOCl photocatalysts has been performed using a transmission electron microscope (TEM) directly in real time. The growth of bismuth nanoparticles on BiOCl nanosheets can be emulated and speeded up driven by the electron beam (e(-) beam) in TEM. The crystallinity, growth and the elemental evolution during the formation of bismuth nanoparticles have also been probed in this work.

  13. Review - Fabrication of crystal-oriented barium-bismuth titanate ceramics in high magnetic field and subsequent reaction sintering

    Directory of Open Access Journals (Sweden)

    Satoshi Tanaka, Yusuke Tomita, Ryoichi Furushima, Hiroyuki Shimizu, Yutaka Doshida and Keizo Uematsu

    2009-01-01

    Full Text Available High magnetic field was applied to fabricate novel lead-free piezoelectric ceramics with a textured structure. A compact of crystallographically oriented grains was prepared by dry forming in a high magnetic field from a mixed slurry of bismuth titanate and barium titanate powders. Bismuth titanate particles with a size of about 1 μ m were used as the host material. In the forming process, the slurry was poured into a mold and set in a magnetic field of 10 T until completely dried. Bismuth titanate particles were highly oriented in the slurry under the magnetic field. The dried powder compact consisted of highly oriented bismuth titanate particles and randomly oriented barium titanate particles. Barium bismuth titanate ceramics with a- and b-axis orientations were successfully produced from the dried compact by sintering at temperatures above 1100 ° C.

  14. Self-limiting growth when using trimethyl bismuth (TMBi) in the metal-organic vapor phase epitaxy (MOVPE) of GaAs1-yBiy

    Science.gov (United States)

    Forghani, Kamran; Guan, Yingxin; Wood, Adam W.; Anand, Amita; Babcock, Susan E.; Mawst, Luke J.; Kuech, Thomas F.

    2014-06-01

    Theoretical and experimental studies have confirmed that the GaAs1-yBiy semiconductor alloy system has potential for long wavelength applications and devices with improved performance over other materials emitting at similar wavelengths. The growth of GaAs1-yBiy by metal-organic vapor phase epitaxy (MOVPE) remains a challenge; bismuth is not easily incorporated into the GaAs matrix due the large difference in electronegativity and covalent radii between As and Bi. These differences often lead to Bi surface segregation or very low incorporation rates of Bi into the GaAs matrix. We have studied the growth of GaAs1-yBiy quantum well structures using trimethyl bismuth as the Bi source. A reduced growth rate is observed with increasing Bi precursor flux into the growth reactor. Additionally, an increase in the growth time for the Bi-containing layer at very low growth temperatures does not lead to a corresponding increase in layer thickness, which is indicative of a near self-limiting growth. Complex compositional profiles deduced from combining x-ray diffraction analysis with the transmission electron microscopy investigations are used to develop a phenomenological model of the MOVPE growth of GaAs1-yBiy heterostructures which includes a complex interplay of the chemical surface species. The presence of a methyl-terminated surface, associated with the use of trimethyl Bi, particularly at low growth temperatures, leads to an effective “site blocking” by Bi precursor inhibiting the growth of GaAs1-yBiy hetero-structures.

  15. Application of Thermodynamic Calculations to the Pyro-refining Process for Production of High Purity Bismuth

    Science.gov (United States)

    Mezbahul-Islam, Mohammad; Belanger, Frederic; Chartrand, Patrice; Jung, In-Ho; Coursol, Pascal

    2017-02-01

    The present work has been performed with the aim to optimize the existing process for the production of high purity bismuth (99.999 pct). A thermo-chemical database including most of the probable impurities of bismuth (Bi-X, X = Ag, Au, Al, Ca, Cu, Fe, Mg, Mn, Na, Ni, Pb, S, Sb, Sn, Si, Te, Zn) has been constructed to perform different thermodynamic calculations required for the refining process. Thermodynamic description for eight of the selected binaries, Bi-Ca, Cu, Mn, Ni, Pb, S, Sb, and Sn, has been given in the current paper. Using the current database, different thermodynamic calculations have been performed to explain the steps involved in the bismuth refining process.

  16. Experimental investigation of the shock response of bismuth under one-dimensional shock-loading

    Science.gov (United States)

    Whiteman, Glenn; Millett, Jeremy; Appleby-Thomas, Gareth; Wood, David; Hameed, Amer

    2017-01-01

    Interest in the dynamic response of bismuth is largely derived from the existence of multiple phase transitions attainable with increasing pressure. In addition, its industrial use has grown in recent years (e.g. in solder as a replacement for lead), in part due to its relatively low toxicity. While some shock experiments have been conducted on bismuth they have largely concentrated on equation of state research at relatively low stresses. To the authors' knowledge the strength behaviour under shock is not prevalent in the literature. To this end, the low pressure response of bismuth targets has been experimentally investigated here using commercial stress gauges mounted in both longitudinal and lateral orientation with respect to the loading axis. Of particular note was the potential to observe the relatively low pressure phase transitions in the lateral stress response.

  17. Fluorescence Emission Centres and the Corresponding Infrared Fluorescence Saturation in a Bismuth-Doped Silica Fibre

    Institute of Scientific and Technical Information of China (English)

    QIU Yan-Qing; SHEN Yong-Hang

    2008-01-01

    We investigate the fluorescence characteristics of bismuth doped silica fibres with and without Al co-dopant which are fabricated by means of modified chemical vapour deposition (MCVD) technique, and find that the fluorescences in the red region (centred around 750nm) and in the infrared region (centred around 1100nm) may originate from different emission sites in the fibre. Strong upconversion phenomena are observed in both Al-codoped and non Al codoped bismuth fibres when the fibres are excited by an acoustic-optic Q-switched Nd: YVO4 laser. Both the aspects indicate that the upper energy level absorption reported in the work of the bismuth doped silica fibre lasers may result from the fluorescence emission sites that are not responsible for the infrared emission. It is thus expected that optimizing the compositions and the fabrication conditions of the fibre and then transferring more fluorescence emission centres are helpful for the infrared emission.

  18. Melting behaviour of lead and bismuth nano-particles in quasicrystalline matrix - The role of interfaces

    Indian Academy of Sciences (India)

    Alok Singh; A P Tsai

    2003-02-01

    Nanomaterials are playing an increasingly important role in modern technologies. Interfaces are crucial in nanotechnology. In this study, we have examined the stability of nanoparticles. Major emphasis is on understanding the effect of interfaces on melting. Melting behaviour of nanocrystalline interfaces, created by embedding lead and bismuth nanoparticles in quasicrystalline matrices, was studied. Sharply faceted and coherent interfaces can be related to sharper melting transitions, while irregularly shaped and incoherent interfaces can be directly correlated with lowering of melting temperatures. It is shown here that solid lead forms a high energy interface with phason strain-free quasicrystal (resulting in a lowering of the melting temperature) while bismuth forms a low energy interface with the quasicrystal (resulting in superheating, unusual for bismuth).

  19. Facile preparation of Bi nanoparticles by novel cathodic dispersion of bulk bismuth electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Chen Xin [Zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua 321004 (China); Chen Shu; Huang Wei [Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), College of Chemistry and Chemical Engineering, Hunan Normal University, Lushan Road, Changsha 410081 (China); Zheng Jufang [Zhejiang Key Laboratory for Reactive Chemistry on Solid Surfaces, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua 321004 (China); Li Zelin, E-mail: lizelin@zjnu.c [Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education of China), College of Chemistry and Chemical Engineering, Hunan Normal University, Lushan Road, Changsha 410081 (China)

    2009-12-01

    A novel electrochemical approach has been developed to prepare clean bismuth nanoparticles (NPs) with a bulk Bi electrode in a 0.5 mol dm{sup -3} NaOH solution under highly cathodic polarization of -8 V versus a saturated mercurous sulfate electrode, requiring no any precursor ions and organic protective agents. The bulk Bi electrode can be facilely dispersed into Bi NPs at the condition of intensive hydrogen evolution. This cathodic dispersion of the bulk Bi electrode involves the formation and decomposition of unstable bismuth hydrides and the aggregation of atomic bismuth from the decomposition. Moreover, Bi{sub 2}O{sub 3} NPs have also been achieved by heating the precursor Bi NPs. Field-emission scanning electron microscopy, transmission electron microscope and X-ray diffraction were used to characterize these NPs. The as-prepared Bi NPs mainly existed in rhombohedral phase.

  20. Design of an Actinide Burning, Lead-Bismuth Cooled Reactor That Produces Low Cost Electricity

    Energy Technology Data Exchange (ETDEWEB)

    C. Davis; S. Herring; P. MacDonald; K. McCarthy; V. Shah; K. Weaver (INEEL); J. Buongiorno; R. Ballinger; K. Doyoung; M. Driscoll; P. Hejzler; M. Kazimi; N. Todreas (MIT)

    1999-07-01

    The purpose of this project is to investigate the suitability of lead-bismuth cooled fast reactors for producing low-cost electricity as well as for actinide burning. The goal is to identify and analyze the key technical issues in core neutronics, materials, thermal-hydraulics, fuels, and economics associated with the development of this reactor concept. The choice of lead-bismuth for the reactor coolant is an actinide burning fast reactor offers enhanced safety and reliability. The advantages of lead-bismuth over sodium as a coolant are related to the following material characteristics: chemical inertness with air and water; higher atomic number; lower vapor pressure at operating temperatures; and higher boiling temperature. Given the status of the field, it was agreed that the focus of this investigation in the first two years will be on the assessment of approaches to optimize core and plant arrangements in order to provide maximum safety and economic potential in this type of reactor.

  1. Poisoning effect of bismuth on modification behaviour of strontium in LM25 alloy

    Indian Academy of Sciences (India)

    S Farahany; A Ourdjini; M H Idris; L T Thai

    2011-10-01

    Nucleation and growth, temperature measurements andmicrostructure observations of silicon phase are presented for strontium modified Al–7%Si (LM25) cast alloy treated with bismuth. The results show that addition of bismuth in strontium modified alloys may have a poisoning effect resulting in lost modification of the silicon phase. With increasing Bi/Sr ratio, thermal analysis measurements showed that the eutectic growth temperature increased remarkably to 573°C and recalescence decreased to 0.2°C and the morphology of silicon displayed the same flakelike structure as in the unmodified alloys. Microstructural observation showed that a minimum Bi/Sr ratio of 1.2 which is equivalent to a Sr/Bi ratio of 0.43 is required for effective strontium modification and neutralization of the poisoning effect of bismuth.

  2. Preparation of bismuth titanate/calcium alginate composite bead and its photocatalytic degradation of dye pollutants

    Science.gov (United States)

    Gan, Huihui; Dong, Nanyang; Lu, Linxiao; Fu, Yan; Zhang, Huining; Qian, Yongxin; Zhang, Kefeng; Jin, Huixia

    2017-08-01

    In this study, the bismuth titanate/calcium alginate composite bead was synthesized by immobilizing bismuth titanate Bi4Ti3O12 particles into 1.5% sodium alginate (SA) matrix. The Bi4Ti3O12 particles were characterized by X-ray diffraction (XRD). The photocatalytic activity for the degradation of dye Rhodamine B in solution by as-prepared bismuth titanate/calcium alginate composite bead was investigated. The as-prepared composite beads CA/BTO-700 exhibited best photocatalytic efficiency for the degradation of RhB compared with CA/BTO-800 and CA/BTO-900 under simulated solar light. After 4 cycles in photocatalytic degradation of RhB, the degradation rate of the CA/BTO-700 nearly remained unchanged.

  3. Change energy photons of radiation, stimulating a photoluminescence in glasses and optical fiber, activated by bismuth

    CERN Document Server

    Ogluzdin, Valeriy E

    2011-01-01

    In the offered review ordering received and published by domestic and foreign researchers of the experimental results showing the phenomenon of a photoluminescence in glasses and optical fiber, activated by bismuth is executed, and from uniform positions representations about the process responsible for a photoluminescence in case of use for excitation of this environment of various laser sources are considered. At interpretation of process of a photoluminescence the known model considering mirror symmetry of features of frequency spectra of a photoluminescence (in this case the maximum values is used: humps or peaks of spectra of a photoluminescence) and the spectra characterising optical losses (absorption) of glass, activated by (atomic) bismuth. For the analysis values of lines of the bismuth, published in reference media are used. This model is added by earlier published specification of the author, according to which to a point of mirror symmetry of such spectra there corresponds frequency of radiation ...

  4. Bismuth Oxide Thin Films Deposited on Silicon Through Pulsed Laser Ablation, for Infrared Detectors

    Science.gov (United States)

    Condurache-Bota, Simona; Constantinescu, Catalin; Tigau, Nicolae; Praisler, Mirela

    2016-12-01

    Infrared detectors are used in many human activities, from industry to military, telecommunications, environmental studies and even medicine. Bismuth oxide thin films have proved their potential for optoelectronic applications, but their uses as infrared sensors have not been thoroughly studied so far. In this paper, pulsed laser ablation of pure bismuth targets within a controlled oxygen atmosphere is proposed for the deposition of bismuth oxide films on Si (100) substrates. Crystalline films were obtained, whose uniformity depends on the deposition conditions (number of laser pulses and the use of a radio-frequency (RF) discharge of the oxygen inside the deposition chamber). The optical analysis proved that the refractive index of the films is higher than 3 and that their optical bandgap is around 1eV, recommending them for infrared applications.

  5. Optical properties of thermally reduced bismuth-doped sodium aluminosilicate glasses

    DEFF Research Database (Denmark)

    Nielsen, K.H.; Smedskjær, Morten Mattrup; Yue, Yuanzheng

    , but also concerning the metal particle formation, and the broadband near infrared luminescence. Both the inward diffusion and the infrared luminescence depend on the bismuth oxidation state. The latter can be varied by adjusting the parameters of the heat-treatment, e.g., time, temperature, and partial......Heat-treatment of multivalent ion containing glasses in a hydrogen atmosphere may cause both reduction of the multivalent ions and ionic inward diffusion, resulting in improved glass properties. Bismuth-doped glasses are also interesting objects not only concerning the reduction induced diffusion...... pressure of hydrogen. Here, we present results on the effect of the heat-treatment on the optical properties of bismuth-doped sodium aluminosilicate glasses....

  6. Radioactive Iodine (I-129) Gas Adsorption by Using Bismuth-Embedded SBA-15

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jae Hwan; Cho, Yong-Jun; Park, Jang Jin; Ahn, Do-Hee [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Yim, Man-Sung [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2015-05-15

    The efficient capture of the long-lived I-129, released as off-gas from nuclear fuel reprocessing, have been of significant concern in the waste management field. In this study, bismuth-embedded SBA-15 mesoporous silica was firstly applied for iodine capture and storage. SBA-15 was functionalized with thiol (-SH) groups, followed by bismuth adsorption with Bi-S bonding, which was thermally treated to form Bi{sub 2}S{sub 3} within SBA-15. The bismuth-embedded SBA-15s demonstrated high iodine loading capacities with 540 mg-I/g-sorbent maximally, which benefitted from the high surface area and porosity of SBA-15 as well as the formation of thermodynamically stable BiI{sub 3} compound. Iodine physisorption could effectively be suppressed due to the large pores present in SBA-15, resulting in chemisorption as a main mechanism for iodine confinement.

  7. Synthesis of binary bismuth-cadmium oxide nanorods with sensitive electrochemical sensing performance

    Energy Technology Data Exchange (ETDEWEB)

    Wen, Yong [Xinjiang Univ., Xinjiang (China). School of Civil Engineering and Architecture; Pei, Lizhai; Wei, Tian [Anhui Univ. of Technology, Anhui (China). School of Materials Science and Engineering

    2017-07-15

    Binary bismuth-cadmium oxide nanorods have been synthesized by a simple hydrothermal process without templates and additives. X-ray diffraction and high-resolution transmission electron microscopy reveal that the nanorods possess single crystalline tetragonal Bi{sub 2}CdO{sub 4} phase. Scanning electron microscopy and transmission electron microscopy images show that the length and diameter of the nanorods are 20-300 nm and 5-10 μm, respectively. The formation of the binary bismuth-cadmium oxide nanorods is closely related to the hydrothermal parameters. The electrochemical sensing performance of the binary bismuth-cadmium oxide nanorods has been investigated using the nanorods as glassy carbon electrode modifiers. The detection limit is 0.19 μM with a linear range of 0.0005-2 mM. The nanorod-modified glassy carbon electrode exhibits good electrocatalytic activity toward L-cysteine and great application potential for electrochemical sensors.

  8. Bismuth subcarbonate as filler particle for an Epoxy-based root canal sealer

    Directory of Open Access Journals (Sweden)

    Eduardo Schwartzer

    2013-01-01

    Full Text Available Introduction: The aim of this study was to evaluate the addition of bismuth subcarbonate with different concentrations regarding the rheological properties of an experimental epoxy-based root canal sealer. Materials and Methods: Endodontic sealers were prepared with epoxy resin-based sealer with bismuth subcarbonate additions of 20%, 40%, 60%, 80%, 100%, and 120%. Flow, film thickness, working time, setting time, dimensional change, sorption, solubility, and cytotoxicity were studied according to the ISO standards. Data were statistically analyzed by one-way ANOVA, and Tukey multiple comparisons were used, with a significance level of 5%. Results: The flow, working time, water sorption, and solubility significantly decreased and the film thickness and dimensional change increased with higher filler particle addition. There were no statistically significant differences for setting time and cytotoxicity between the filler particle proportions. Conclusion: Experimental resin-based sealer with bismuth subcarbonate addition up to 40% can be an alternative for root canal sealer.

  9. Glass-like carbon, pyrolytic graphite or nanostructured carbon for electrochemical sensing of bismuth ion?

    Directory of Open Access Journals (Sweden)

    Jadranka Milikić

    2016-06-01

    Full Text Available Different carbon electrodes were explored for application in electroanalysis, namely for sensing of bismuth ion as model analyte. Carbon materials tested included glassy carbon, basal and edge plane pyrolytic graphite, as well as nanostructured carbonized polyaniline prepared in the presence of 3,5-dinitrosalicylic acid. Bismuth ion was chosen as model analyte as protocol for its detection and quantifications is still to be determined. Herein, anodic stripping voltammetry was used with study of effect of several parameters such as scan rate and deposition time. Electrode based on carbonized polyaniline showed the highest activity for bismuth ion sensing in terms of the highest current densities recorded both in a laboratory and in real sample, while basal plane pyrolytic graphite electrode gave the lowest limit of detection.

  10. Phosphorescent Nanocluster Light-Emitting Diodes.

    Science.gov (United States)

    Kuttipillai, Padmanaban S; Zhao, Yimu; Traverse, Christopher J; Staples, Richard J; Levine, Benjamin G; Lunt, Richard R

    2016-01-13

    Devices utilizing an entirely new class of earth abundant, inexpensive phosphorescent emitters based on metal-halide nanoclusters are reported. Light-emitting diodes with tunable performance are demonstrated by varying cation substitution to these nanoclusters. Theoretical calculations provide insight about the nature of the phosphorescent emitting states, which involves a strong pseudo-Jahn-Teller distortion.

  11. Bismuth Passivation Technique for High-Resolution X-Ray Detectors

    Science.gov (United States)

    Chervenak, James; Hess, Larry

    2013-01-01

    The Athena-plus team requires X-ray sensors with energy resolution of better than one part in 3,000 at 6 keV X-rays. While bismuth is an excellent material for high X-ray stopping power and low heat capacity (for large signal when an X-ray is stopped by the absorber), oxidation of the bismuth surface can lead to electron traps and other effects that degrade the energy resolution. Bismuth oxide reduction and nitride passivation techniques analogous to those used in indium passivation are being applied in a new technique. The technique will enable improved energy resolution and resistance to aging in bismuth-absorber-coupled X-ray sensors. Elemental bismuth is lithographically integrated into X-ray detector circuits. It encounters several steps where the Bi oxidizes. The technology discussed here will remove oxide from the surface of the Bi and replace it with nitridized surface. Removal of the native oxide and passivating to prevent the growth of the oxide will improve detector performance and insulate the detector against future degradation from oxide growth. Placing the Bi coated sensor in a vacuum system, a reduction chemistry in a plasma (nitrogen/hydrogen (N2/H2) + argon) is used to remove the oxide and promote nitridization of the cleaned Bi surface. Once passivated, the Bi will perform as a better X-ray thermalizer since energy will not be trapped in the bismuth oxides on the surface. A simple additional step, which can be added at various stages of the current fabrication process, can then be applied to encapsulate the Bi film. After plasma passivation, the Bi can be capped with a non-diffusive layer of metal or dielectric. A non-superconducting layer is required such as tungsten or tungsten nitride (WNx).

  12. The effect of bismuth subcitrate in patients with diarrhea predominant irritable bowel syndrome

    Directory of Open Access Journals (Sweden)

    Kalani M

    2010-09-01

    Full Text Available "nBackground: The irritable bowel syndrome (IBS is one of the most common chronic medical conditions. Various mechanisms, including altered gut flora and/or small bowel bacterial overgrowth, have been suggested to play a role in the development of gas-related symptoms aim of study. The clinical evidence of small intestinal bacterial overgrowth as an important etiology of irritable bowel syndrome continues to accumulate. Clinical symptoms of bacterial overgrowth and irritable bowel syndrome are similar; however, a definitive cause-and-effect relationship remains unproven. It is unclear whether motility dysfunction causes bacterial overgrowth or gas products of"nenteric bacteria affect intestinal motility in irritable bowel syndrome."n "nMethods: In a randomized double-blind placebo-controlled trial consisting of treatment with bismuth subcitrate. Primary efficacy variable was subjective symptoms; frequency of abdominal pain, Number of bowel movement & Bloating/distension."n "nResults: 119 patients were enrolled (59 bismuth subcitrate and 60 placebo recipients. At the end of phase 2, all symptom scores dropped significantly both in bismuth subcitrate and placebo group (p<0.001. There was not a significant difference in symptom relief with bismuth subcitrate versus placebo administration."n "nConclusions: There was not a significant difference in symptom relief with bismuth subcitrate versus placebo in IBS patients. Whether antibiotics can improve quality of life in patients with irritable bowel syndrome warrants further research."nInterventions: Participants were randomly assigned to receive 120mg bismuth subcitrate four times daily for 14 days (n=59 or placebo (n=60.

  13. Light emitting device having peripheral emissive region

    Science.gov (United States)

    Forrest, Stephen R

    2013-05-28

    Light emitting devices are provided that include one or more OLEDs disposed only on a peripheral region of the substrate. An OLED may be disposed only on a peripheral region of a substantially transparent substrate and configured to emit light into the substrate. Another surface of the substrate may be roughened or include other features to outcouple light from the substrate. The edges of the substrate may be beveled and/or reflective. The area of the OLED(s) may be relatively small compared to the substrate surface area through which light is emitted from the device. One or more OLEDs also or alternatively may be disposed on an edge of the substrate about perpendicular to the surface of the substrate through which light is emitted, such that they emit light into the substrate. A mode expanding region may be included between each such OLED and the substrate.

  14. Dissolved oxygen control and monitoring implementation in the liquid lead bismuth eutectic loop: HELIOS

    Science.gov (United States)

    Nam, Hyo On; Lim, Jun; Han, Dong Yoon; Hwang, Il Soon

    2008-06-01

    A 12 m tall LBE coolant loop, named as HELIOS, has been developed by thermal-hydraulic scaling of the PEACER-300MWe. Thermo-hydraulic experiment and materials test are the principal purposes of HELIOS operation. In this study, an yttria stabilized zirconia (YSZ) based oxygen sensor that was hermetically sealed for long-term applications using the electromagnetically swaged metal-ceramic joining method, have been developed for high temperature oxygen control application over a long period of time. The rugged electrode design has been calibrated to absolute metal-oxide equilibrium by using a first principle of detecting pure metal-oxide transition using electrochemical impedance spectroscopy (EIS). During the materials tests in HELIOS, dissolved oxygen concentration was administered at the intended condition of 10 -6 wt% by direct gas bubbling with Ar + 4%H 2, Ar + 5%O 2 and/or pure Ar while corrosion tests were conducted for up to 1000 h with inspection after each 333 h. During the total 1000 h corrosion test, oxygen concentration was measured by oxygen sensor. The result confirmed that the direct gas bubbling method is a viable and practical option for controlling oxygen concentration in large loops including HELIOS.

  15. Observation of a nematic quantum Hall liquid on the surface of bismuth

    Science.gov (United States)

    Feldman, Benjamin E.; Randeria, Mallika T.; Gyenis, András; Wu, Fengcheng; Ji, Huiwen; Cava, R. J.; MacDonald, Allan H.; Yazdani, Ali

    2016-10-01

    Nematic quantum fluids with wave functions that break the underlying crystalline symmetry can form in interacting electronic systems. We examined the quantum Hall states that arise in high magnetic fields from anisotropic hole pockets on the Bi(111) surface. Spectroscopy performed with a scanning tunneling microscope showed that a combination of single-particle effects and many-body Coulomb interactions lift the six-fold Landau level (LL) degeneracy to form three valley-polarized quantum Hall states. We imaged the resulting anisotropic LL wave functions and found that they have a different orientation for each broken-symmetry state. The wave functions correspond to those expected from pairs of hole valleys and provide a direct spatial signature of a nematic electronic phase.

  16. Synthesis and characterization of UV-treated Fe-doped bismuth lanthanum titanate-doped TiO2 layers in dye-sensitized solar cells

    Science.gov (United States)

    Song, Myoung Geun; Bark, Chung Wung

    2016-06-01

    Dye-sensitized solar cells (DSSCs) based on titanium dioxide (TiO2) have been extensively studied because they constitute promising low-cost alternatives to their conventional semiconductor-based counterparts. However, much of the effort aimed at achieving high conversion efficiencies has focused on dye and liquid electrolytes. In this work, we report the photovoltaic characteristics of DSSCs fabricated by mixing TiO2 with Fe-doped bismuth lanthanum titanate (Fe-BLT). These nanosized Fe-BLT powders were prepared by using a high-energy ball-milling process. In addition, we used a UV radiation-ozone (UV-O3) treatment to change the surface wettability of TiO2 from hydrophobic to hydrophilic and thereby prevented the easy separation of the Fe-BLT-mixed TiO2 from the fluorine-doped tin-oxide (FTO) coating glass.

  17. A study of the neutron irradiation effects on the susceptibility to embrittlement of A316L and T91 steels in lead-bismuth eutectic

    Energy Technology Data Exchange (ETDEWEB)

    Sapundjiev, D. [TCH, SCK-CEN, Boeretang 200, Mol, B-2400 (Belgium)]. E-mail: danislav.sapundjiev@sckcen.be; Al Mazouzi, A. [TCH, SCK-CEN, Boeretang 200, Mol, B-2400 (Belgium); Van Dyck, S. [TCH, SCK-CEN, Boeretang 200, Mol, B-2400 (Belgium)

    2006-09-15

    The effects of neutron irradiation on the susceptibility to liquid metal embrittlement of two primary selected materials for MYRRHA project an accelerator driven system (ADS), was investigated by means of slow strain rate tests (SSRT). The latter were carried out at 200 deg. C in nitrogen and in liquid Pb-Bi at a strain rate of 5 x 10{sup -6} s{sup -1}. The small tensile specimens were irradiated at the BR-2 reactor in the MISTRAL irradiation rig at 200 deg. C for 3 reactor cycles to reach a dose of about 1.50 dpa. The SSR tests were carried out under poor and under dissolved oxygen conditions ({approx}1.5 x 10{sup -12} wt% dissolved oxygen) which at this temperature will favour formation of iron and chromium oxides. Although both materials differ in structure (fcc for A316L against bcc for T91), their flow behaviour in contact with liquid lead bismuth eutectic before and after irradiation is very similar. Under these testing conditions none of them was found susceptible to liquid metal embrittlement (LME)

  18. Growth morphology and structure of bismuth thin films on GaSb(110)

    DEFF Research Database (Denmark)

    Gemmeren, T. van; Lottermoser, L.; Falkenberg, G.

    1998-01-01

    Photoelectron spectroscopy, low-energy electron diffraction, scanning tunneling microscopy and surface X-ray diffraction were used to investigate the growth of thin layers of bismuth on GaSb(110). At submonolayer coverages, growth of two-dimensional islands occurs. A uniform (1 x I)-reconstructio...... that the (1 x 1)-phases formed by antimony and bismuth adsorbates on (110) surfaces of other III-V compound semiconductors are also described by the epitaxial continued layer model. (C) 1998 Elsevier Science B.V. All rights reserved....

  19. Making bispirin: synthesis, structure and activity against Helicobacter pylori of bismuth(III) acetylsalicylate.

    Science.gov (United States)

    Andrews, Philip C; Blair, Victoria L; Ferrero, Richard L; Junk, Peter C; Kumar, Ish

    2013-04-11

    Reaction of Bi(O(t)Bu)3 with aspirin (acetylsalicylic acid = aspH) in dry toluene results in the bismuth(III) complex, [Bi(O2C(C6H4)OAc)3]∞ 1 (O2C(C6H4)OAc = asp), minimum inhibitory concentration (MIC) against Helicobacter pylori ≥ 6.25 μg mL(-1), while the inclusion of a stoichiometric equivalent of KO(t)Bu leads to crystals of the bismuthate salt [KBi(O2C(C6H4)OAc)4]∞ 2.

  20. Simultaneous enhancements in photon absorption and charge transport of bismuth vanadate photoanodes for solar water splitting

    OpenAIRE

    Kim, Tae Woo; Ping, Yuan; Galli, Giulia A.; Choi, Kyoung-Shin

    2015-01-01

    n-Type bismuth vanadate has been identified as one of the most promising photoanodes for use in a water-splitting photoelectrochemical cell. The major limitation of BiVO4 is its relatively wide bandgap (∼2.5 eV), which fundamentally limits its solar-to-hydrogen conversion efficiency. Here we show that annealing nanoporous bismuth vanadate electrodes at 350 °C under nitrogen flow can result in nitrogen doping and generation of oxygen vacancies. This gentle nitrogen treatment not only effective...

  1. Investigation on bismuth-oxide photonic crystal fiber for optical parametric amplification

    Institute of Scientific and Technical Information of China (English)

    JIN Cang; RAO Lan; YUAN Jin-hui; SHEN Xiang-wei; YU Chong-xiu

    2011-01-01

    A hexagonal solid-core bismuth-oxide micro-structure fiber is developed to balance its dispersion and nonlinearity. This simulation and calculation results show that the bismuth-oxide photonic crystal fiber (Bi-PCF) has near zero dispersion around 1550 nm. Its dispersion slop in the communication wavelength range is also relatively flat. Moreover, both nonlinear coefficient and model field distribution are obtained. Compared with the experimental results by SiO-PCF, it can be seen that the Bi-PCF shows excellent characteristics for the optical parametric amplification (OPA).

  2. Spin-Polarized Tunneling Study on Spin-Momentum Locking in the Topological Insulator Bismuth Selenide

    Science.gov (United States)

    Chen, Ching-Tzu; Liu, Luqiao; Richardella, Anthony; Garate, Ion; Zhu, Yu; Samarth, Nitin

    2015-03-01

    In this talk, we will demonstrate that the helical spin texture on topological insulator (TI) surfaces can be electrically detected using four-terminal tunnel junction devices with ferromagnetic top electrodes. Consistent results are obtained in both the Edelstein and spin-galvanic effect configurations, allowing a quantitative determination of the charge-spin conversion efficiency in bismuth selenide. By applying finite DC biases at the junction, we further extract the energy dependence of the effective spin polarization in bismuth selenide. The observed temperature stability up to 200K suggests that TIs can be highly promising for room-temperature spintronics applications

  3. Simultaneous Determination of Bismuth and Copper by Square Wave Voltammetry in The Presence of Ethylenediaminetetraacedic Acid

    OpenAIRE

    HASDEMİR, Erdoğan; KARABODUK, Kuddusi

    2010-01-01

    A sensitive and selective method for the simultaneous determination of copper and bismuth by square wave voltammetry (SWV) was developed using ethylenediaminetetraacedic acid (EDTA) as complexing agent. Factors affecting the pH and concentrations ratios of copper and bismuth were investigated. Optimal analytical conditions were  found to be: pH of 8.0, the ratio of [Cu2+]/[Bi3+] was 0.13-2.5. The limit of detection (3δ) was 1.26 × 10-7 mol dm-3 for copper,  1.30×10...

  4. Shielding of emitting dust particles

    Science.gov (United States)

    Luca Delzanno, Gian; Lapenta, Giovanni; Rosenberg, Marlene

    2003-10-01

    In the present work we focus on the role of electron emission (either thermionic or photoelectric) in charging an object immersed in a plasma. In fact, it is well known that the higher mobility of the plasma electrons (that would lead to negatively charged objects) can be overcome by electron emission, thus reversing the object polarity. Moreover, recent work [1] has shown how electron emission can fundamentally affect the shielding potential around the dust. In particular, depending on the physical parameters of the system (that were chosen such to correspond to common experimental conditions), the shielding potential can develop an attractive potential well. The aim of the present work is two-fold. First, we will present a parametric study in order to enlight the conditions for the formation, as well as the stability of the well. Furthermore, simulations will be presented with physical parameters corresponding to the ionosphere, thus extending our study to the case of meteroids. [1] G.L. Delzanno, G. Lapenta, M. Rosenberg, "Attractive Potential among Thermionically Emitting Microparticles", submitted.

  5. Bismuth subsalicylate nanoparticles with anaerobic antibacterial activity for dental applications

    Science.gov (United States)

    Vega-Jiménez, A. L.; Almaguer-Flores, A.; Flores-Castañeda, M.; Camps, E.; Uribe-Ramírez, M.; Aztatzi-Aguilar, O. G.; De Vizcaya-Ruiz, A.

    2017-10-01

    In recent years, nanomaterials have been used in the medical-dental field as new alternative antimicrobial agents. Bismuth subsalicylate (BSS) has been used as an antimicrobial agent, but the effect of BSS in the form of nanoparticles (BSS-nano) as a potential antimicrobial agent has not been tested, in specific against bacteria responsible for periodontal disease. The aim of this study was to evaluate the antibacterial effect of BSS-nano against oral anaerobic bacteria and to assess the safety of BSS-nano by evaluating their cytotoxicity in human gingival fibroblast (HGF-1) cells. BSS-nano were synthesized by laser ablation and were previously physico-chemically characterized using in vitro assays. The antibacterial activity was measured using the tetrazolium-based XTT assay, and cytotoxicity was determined using lactate dehydrogenase (LDH) and MTS assays in HGF-1 cells. Transmission electron microscopy of HGF-1 exposed to BSS-nano was also performed. BSS-nano was shown to have a primary size of 4–22 nm and a polygonal shape. Among the tested bacterial strains, those with a greater sensitivity to BSS-nano (highest concentration of 21.7 μg ml‑1) were A. actinomycetemcomitans, C. gingivalis, and P. gingivalis. BSS-nano at a concentration of 60 μg ml‑1 showed low cytotoxicity (6%) in HFG-1 cells and was mainly localized intracellularly in acidic vesicles. Our results indicate that the concentration of BSS-nano used as an effective antibacterial agent does not induce cytotoxicity in mammalian cells; thus, BSS-nano can be applied as an antibacterial agent in dental materials or antiseptic solutions.

  6. Microwave-hydrothermal synthesis of perovskite bismuth ferrite nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Biasotto, G. [Laboratorio Interdisciplinar em Ceramica (LIEC), Departamento de Fisico-Quimica, Instituto de Quimica, UNESP, CEP 14800-900, Araraquara, SP (Brazil); Simoes, A.Z., E-mail: alezipo@yahoo.com [Universidade Estadual Paulista-Unesp, Faculdade de Engenharia de Guaratingueta, Av. Dr. Ariberto Pereira da Cunha, 333, Bairro Pedregulho, CEP 12516-410, Guaratingueta, SP (Brazil); Foschini, C.R.; Zaghete, M.A.; Varela, J.A.; Longo, E. [Laboratorio Interdisciplinar em Ceramica (LIEC), Departamento de Fisico-Quimica, Instituto de Quimica, UNESP, CEP 14800-900, Araraquara, SP (Brazil)

    2011-12-15

    Highlights: Black-Right-Pointing-Pointer BiFeO{sub 3} (BFO) nanoparticles were grown by hydrothermal microwave method (HTMW). Black-Right-Pointing-Pointer The soaking time is effective in improving phase formation. Black-Right-Pointing-Pointer Rietveld refinement reveals an orthorhombic structure. Black-Right-Pointing-Pointer The observed magnetism of the BFO crystallites is a consequence of particle size. Black-Right-Pointing-Pointer The HTMW is a genuine technique for low temperatures and short times of synthesis. -- Abstract: Hydrothermal microwave method (HTMW) was used to synthesize crystalline bismuth ferrite (BiFeO{sub 3}) nanoparticles (BFO) in the temperature of 180 Degree-Sign C with times ranging from 5 min to 1 h. BFO nanoparticles were characterized by means of X-ray analyses, FT-IR, Raman spectroscopy, TG-DTA and FE-SEM. X-ray diffraction results indicated that longer soaking time was benefit to refraining the formation of any impurity phases and growing BFO crystallites into almost single-phase perovskites. Typical FT-IR spectra for BFO nanoparticles presented well defined bands, indicating a substantial short-range order in the system. TG-DTA analyses confirmed the presence of lattice OH{sup -} groups, commonly found in materials obtained by HTMW process. Compared with the conventional solid-state reaction process, submicron BFO crystallites with better homogeneity could be produced at the temperature as low as 180 Degree-Sign C. These results show that the HTMW synthesis route is rapid, cost effective, and could be used as an alternative to obtain BFO nanoparticles in the temperature of 180 Degree-Sign C for 1 h.

  7. Formic acid oxidation at platinum-bismuth catalysts

    Directory of Open Access Journals (Sweden)

    Popović Ksenija Đ.

    2015-01-01

    Full Text Available The field of heterogeneous catalysis, specifically catalysis on bimetallic surfaces, has seen many advances over the past few decades. Bimetallic catalysts, which often show electronic and chemical properties that are distinct from those of their parent metals, offer the opportunity to obtain new catalysts with enhanced selectivity, activity, and stability. The oxidation of formic acid is of permanent interest as a model reaction for the mechanistic understanding of the electrooxidation of small organic molecules and because of its technical relevance for fuel cell applications. Platinum is one of the most commonly used catalysts for this reaction, despite the fact that it shows a few significant disadvantages: high cost and extreme susceptibility to poisoning by CO. To solve this problem, several approaches have been used, but generally, they all consist in the modification of platinum with a second element. Especially, bismuth has received significant attention as Pt modifier. According to the results presented in this survey dealing with the effects influencing the formic acid oxidation it was found that two types of Pt-Bi bimetallic catalysts (bulk and low loading deposits on GC showed superior catalytic activity in terms of the lower onset potential and oxidation current density, as well as exceptional stability compared to Pt. The findings in this report are important for the understanding of mechanism of formic acid electrooxidation on a bulk alloy and decorated surface, for the development of advanced anode catalysts for direct formic acid fuel cells, as well as for the synthesis of novel low-loading bimetallic catalysts. The use of bimetallic compounds as the anode catalysts is an effective solution to overcoming the problems of the formic acid oxidation current stability for long term applications. In the future, the tolerance of both CO poisoning and electrochemical leaching should be considered as the key factors in the development

  8. Experimental investigation of the thermal hydraulics in lead bismuth eutectic-helium experimental loop of an accelerator-driven system

    Energy Technology Data Exchange (ETDEWEB)

    Xi, Wenxuan; Wang, Yong Wei; Li, Xun Feng; Huai, Xiulan; Cal, Jun [Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing (China)

    2016-10-15

    The heat transfer characteristics between liquid lead bismuth eutectic (LBE) and helium are of great significance for the two-loop cooling system based on an accelerator-driven system (ADS). This paper presents an experimental study on the resistance characteristics and heat transfer performance in a LBE-helium experimental loop of ADS. Pressure drops in the LBE loop, the main heat transfer, and the coupled heat transfer characteristics between LBE and helium are investigated experimentally. The temperature of LBE has a significant effect on the LBE thermo-physical properties, and is therefore considered in the prediction of pressure drops. The results show that the overall heat transfer coefficient increases with the increasing helium flow rate and the decreasing inlet temperature of helium. Increasing the LBE Reynolds number and LBE inlet temperature promotes the heat transfer performance of main heat transfer and thus the overall heat transfer coefficient. The experimental results give an insight into the flow and heat transfer properties in a LBE-helium heat exchanger and are helpful for the optimization of an ADS system design.

  9. The Effect of Beam Intensity on Temperature Distribution in ADS Windowless Lead-Bismuth Eutectic Spallation Target

    Directory of Open Access Journals (Sweden)

    Jie Liu

    2014-01-01

    Full Text Available The spallation target is the component coupling the accelerator and the reactor and is regarded as the “heart” of the accelerator driven system (ADS. Heavy liquid metal lead-bismuth eutectic (LBE is served as core coolant and spallation material to carry away heat deposition of spallation reaction and produce high flux neutron. So it is very important to study the heat transfer process in the target. In this paper, the steady-state flow pattern has been numerically obtained and taken as the input for the nuclear physics calculation, and then the distribution of the extreme large power density of the heat load is imported back to the computational fluid dynamics as the source term in the energy equation. Through the coupling, the transient and steady-state temperature distribution in the windowless spallation target is obtained and analyzed based on the flow process and heat transfer. Comparison of the temperature distribution with the different beam intensity shows that its shape is the same as broken wing of the butterfly. Nevertheless, the maximum temperature as well as the temperature gradient is different. The results play an important role and can be applied to the further design and optimization of the ADS windowless spallation target.

  10. Bismuth-catalyzed and doped silicon nanowires for one-pump-down fabrication of radial junction solar cells.

    Science.gov (United States)

    Yu, Linwei; Fortuna, Franck; O'Donnell, Benedict; Jeon, Taewoo; Foldyna, Martin; Picardi, Gennaro; Roca i Cabarrocas, Pere

    2012-08-08

    Silicon nanowires (SiNWs) are becoming a popular choice to develop a new generation of radial junction solar cells. We here explore a bismuth- (Bi-) catalyzed growth and doping of SiNWs, via vapor-liquid-solid (VLS) mode, to fabricate amorphous Si radial n-i-p junction solar cells in a one-pump-down and low-temperature process in a single chamber plasma deposition system. We provide the first evidence that catalyst doping in the SiNW cores, caused by incorporating Bi catalyst atoms as n-type dopant, can be utilized to fabricate radial junction solar cells, with a record open circuit voltage of V(oc) = 0.76 V and an enhanced light trapping effect that boosts the short circuit current to J(sc) = 11.23 mA/cm(2). More importantly, this bi-catalyzed SiNW growth and doping strategy exempts the use of extremely toxic phosphine gas, leading to significant procedure simplification and cost reduction for building radial junction thin film solar cells.

  11. Glutathione and multidrug resistance protein transporter mediate a self-propelled disposal of bismuth in human cells

    Science.gov (United States)

    Hong, Yifan; Lai, Yau-Tsz; Chan, Godfrey Chi-Fung; Sun, Hongzhe

    2015-01-01

    Glutathione and multidrug resistance protein (MRP) play an important role on the metabolism of a variety of drugs. Bismuth drugs have been used to treat gastrointestinal disorder and Helicobacter pylori infection for decades without exerting acute toxicity. They were found to interact with a wide variety of biomolecules, but the major metabolic pathway remains unknown. For the first time (to our knowledge), we systematically and quantitatively studied the metabolism of bismuth in human cells. Our data demonstrated that over 90% of bismuth was passively absorbed, conjugated to glutathione, and transported into vesicles by MRP transporter. Mathematical modeling of the system reveals an interesting phenomenon. Passively absorbed bismuth consumes intracellular glutathione, which therefore activates de novo biosynthesis of glutathione. Reciprocally, sequestration by glutathione facilitates the passive uptake of bismuth and thus completes a self-sustaining positive feedback circle. This mechanism robustly removes bismuth from both intra- and extracellular space, protecting critical systems of human body from acute toxicity. It elucidates the selectivity of bismuth drugs between human and pathogens that lack of glutathione, such as Helicobacter pylori, opening new horizons for further drug development. PMID:25737551

  12. DC electromagnetic pump applied to liquid metal flow control used in fast reactors; Bomba eletromagnetica de corrente continua aplicada ao controle de escoamento de metais liquidos utilizados em reatores rapidos

    Energy Technology Data Exchange (ETDEWEB)

    Borges, Eduardo M.; Braz Filho, Francisco A.; Guimaraes, Lamartine N.F. [Centro Tecnico Aeroespacial (CTA), Sao Jose dos Campos, SP (Brazil). Inst. de Estudos Avancados (IEAv)]. E-mail: Eduardo@ieav.cta.br; fbraz@ieav.cta.br; guimarae@ieav.cta.br

    2005-07-01

    Electromagnetic pumps use Faraday principle to liquid metal flow control, where DC electric current and magnetic field applied produce the Lorentz force on the liquid metal. In this paper the results of the computational simulation are compared to experimental data of Mercury DC electromagnetic pump operation and the BEMC-1 code is used to evaluation of DC electromagnetic pump performance applied to liquid metal flow control as Sodium, Lead and Bismuth, used in fast reactors. (author)

  13. Adsorption of volatile polonium and bismuth species on metals in various gas atmospheres. Pt. I. Adsorption of volatile polonium and bismuth on gold

    Energy Technology Data Exchange (ETDEWEB)

    Maugeri, Emilio Andrea; Neuhausen, Joerg; Dressler, Rugard; Piguet, David; Voegele, Alexander; Schumann, Dorothea [Paul Scherrer Institut (PSI), Villigen (Switzerland). Lab. for Radiochemistry; Eichler, Robert [Paul Scherrer Institut (PSI), Villigen (Switzerland). Lab. for Radiochemistry; Bern Univ. (Switzerland). Dept. for Chemistry and Biochemistry; Rijpstra, Kim [Ghent Univ., Zwijnaarde (Belgium). Center for Molecular Modeling (CMM); Cottenier, Stefaan [Ghent Univ., Zwijnaarde (Belgium). Center for Molecular Modeling (CMM); Ghent Univ., Zwijnaarde (Belgium). Dept. of Materials Science and Engineering

    2016-07-01

    Polonium isotopes are considered the most hazardous radionuclides produced during the operation of accelerator driven systems (ADS) when lead-bismuth eutectic (LBE) is used as the reactor coolant and as the spallation target material. In this work the use of gold surfaces for capturing polonium from the cover gas of the ADS reactor was studied by thermochromatography. The results show that gaseous monoatomic polonium, formed in dry hydrogen, is adsorbed on gold at 1058 K. Its adsorption enthalpy was calculated as -250±7 kJ mol{sup -1}, using a Monte Carlo simulation code. Highly volatile polonium species that were observed in similar experiments in fused silica columns in the presence of moisture in both inert and reducing gas were not detected in the experiments studying adsorption on gold surfaces. PoO{sub 2} is formed in both dry and moist oxygen, and its interaction with gold is characterized by transport reactions. The interaction of bismuth, present in large amounts in the atmosphere of the ADS, with gold was also evaluated. It was found that bismuth has a higher affinity for gold, compared to polonium, in an inert, reducing, and oxidizing atmosphere. This fact must be considered when using gold as a material for filtering polonium in the cover gas of ADS.

  14. Development of a liquid Pb-Bi target for high-power ISOL facilities

    Energy Technology Data Exchange (ETDEWEB)

    Houngbo, D., E-mail: dhoungbo@sckcen.be [Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, B-2400 Mol (Belgium); Department of Flow, Heat and Combustion Mechanics, Ghent University (UGent), St.-Pietersnieuwstraat 41, B-9000 Gent (Belgium); Bernardes, A.P. [CERN, 1211 Geneva 23 (Switzerland); David, J.C. [CEA/Saclay, 91191 Gif-sur-Yvette cedex (France); Delonca, M. [CERN, 1211 Geneva 23 (Switzerland); IRTES-M3M & IRTES-LERMPS, Université de Technologie de Belfort-Montbeliard, 90010 Belfort Cedex (France); Kravalis, K. [Institute of Physics of University of Latvia (IPUL), 32 Miera iela, Salaspils LV-2169 (Latvia); Lahiri, S. [Saha Institute of Nuclear Physics 1/AF Bidhannagar, Kolkata 700064 (India); Losito, R.; Maglioni, C. [CERN, 1211 Geneva 23 (Switzerland); Marchix, A. [CEA/Saclay, 91191 Gif-sur-Yvette cedex (France); Mendonca, T.M. [CERN, 1211 Geneva 23 (Switzerland); Popescu, L. [Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, B-2400 Mol (Belgium); Schumann, D. [Paul Scherrer Institute (PSI), 5232 Villigen PSI (Switzerland); Schuurmans, P. [Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, B-2400 Mol (Belgium); Stora, T.; Vollaire, J. [CERN, 1211 Geneva 23 (Switzerland); Vierendeels, J. [Department of Flow, Heat and Combustion Mechanics, Ghent University (UGent), St.-Pietersnieuwstraat 41, B-9000 Gent (Belgium)

    2016-06-01

    This paper describes some R&D activities conducted in support of the design and safe operation of a high-power liquid Pb-Bi target within the LIEBE (Liquid Eutectic Lead Bismuth Loop Target for EURISOL) project. The target material is lead bismuth eutectic (LBE) which also acts as a primary coolant. As a consequence of interaction of the highly pulsed 1.4-GeV protons at ISOLDE with the target, heat powers of the order of 2 GW would be instantaneously deposited in the target during a bunch. Considerable R&D effort is thus required to demonstrate its continued coolability and structural integrity. This paper mainly reports on the conjugate flow (CFD) and heat deposition (Monte Carlo) calculations, not accounting for Fluid–Structure Interactions.

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

    Science.gov (United States)

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

    2017-04-01

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

  16. 1.3 µm Raman-bismuth fiber amplifier pumped by semiconductor disk laser.

    Science.gov (United States)

    Chamorovskiy, A; Rautiainen, J; Rantamäki, A; Golant, K M; Okhotnikov, O G

    2011-03-28

    A hybrid Raman-bismuth fiber amplifier pumped in co-propagation configuration by a single 1.22 µm semiconductor disk laser is presented. The unique attribute of this dual-gain system is that both amplifiers require the pump source with the same wavelength because pump-Stokes spectral shift in 1.3 µm Raman amplifier and pump-gain bandwidth separation in 1.3 µm bismuth fiber amplifier have the same value. Residual pump power at the output of Raman amplifier in this scheme is efficiently consumed by bismuth-doped fiber thus increasing the overall conversion efficiency. The small-signal gain of 18 dB at 1.3 W of pump power has been achieved for hybrid scheme which is by 9 dB higher as compared with isolated Raman amplifier without bismuth fiber. Low noise performance of pump semiconductor disk laser with RIN of -150 dB/Hz combined with nearly diffraction-limited beam quality and Watt-level output powers allows for efficient core-pumping of a single-mode fiber amplifier systems and opens up new opportunities for amplification in O-band spectral range.

  17. Low-temperature, template-free synthesis of single-crystal bismuth telluride nanorods

    Energy Technology Data Exchange (ETDEWEB)

    Purkayastha, A. [Department of Materials Science and Engineering, Rensselaer Polytechnic Institute, 110 Eighth Street, Troy, NY 12180 (United States); Lupo, F. [Max Planck Institut fuer Metallforschung, Heisenbergstrasse 3, D-70569 Stuttgart (Germany); Kim, S.; Borca-Tasciuc, T. [Department of Mechanical, Aerospace, and Nuclear Engineering, Rensselaer Polytechnic Institute, 110 Eighth Street, Troy, NY 12180 (United States); Ramanath, G. [Department of Materials Science and Engineering, Rensselaer Polytechnic Institute, 110 Eighth Street, Troy, NY 12180 (United States); Max Planck Institut fuer Festkoerperforschung, Heisenbergstrasse 1, D-70569 Stuttgart (Germany)

    2006-02-17

    Synthesis of single-crystal bismuth telluride nanorods is reported by using a low-temperature, template-free approach. Films of thioglycolic acid functionalized nanorods doped with sulfur exhibit n-type behavior with a high Seebeck coefficient, holding promise for thermoelectric device applications. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  18. Radioprotection to the Gonads in Pediatric Pelvic Radiography: Effectiveness of Developed Bismuth Shield

    Directory of Open Access Journals (Sweden)

    Vahid Karami

    2017-06-01

    Full Text Available Background: The use and effectiveness of traditional lead gonad shields in pediatric pelvic radiography has been challenged by several literatures over the past two decades. The aim of this study was to develop a new radioprotective gonad shields to be use in pediatric pelvic radiography. Materials and Methods: The commercially available 0.06 mm lead equivalent bismuth garment has cropped squarely and used as ovarian shield to cover the entire region of pelvis. In order to prevent deterioration of image quality due to beam hardening artifacts, a 1-cm foam as spacer was located between the shield and patients pelvis. Moreover, we added a lead piece at the cranial position of the bismuth garment to absorb the scatter radiations to the radiosensitive organs. In girls, 49 radiographs with shield and 46 radiographs without shield was taken. The radiation dose was measured using thermoluminescent dosimeters (TLDs. Image quality assessments were performed using the European guidelines. For boys, the lead testicular shields was developed using 2 cm bismuth garment, added to the sides. The prevalence and efficacy of testicular shields was assessed in clinical practice fromFebruary 2016 to June 2016. Results: Without increasing the dose to the breast, thyroid and the lens of the eyes, the use of bismuth shield has reduced the entrance skin dose(ESD of the pelvis and radiation dose to the ovaries by 62.2% and 61.7%, respectively (P

  19. Group III-nitride thin films grown using MBE and bismuth

    Science.gov (United States)

    Kisielowski, Christian K.; Rubin, Michael

    2000-01-01

    The present invention comprises growing gallium nitride films in the presence of bismuth using MBE at temperatures of about 1000 K or less. The present invention further comprises the gallium nitride films fabricated using the inventive fabrication method. The inventive films may be doped with magnesium or other dopants. The gallium nitride films were grown on sapphire substrates using a hollow anode Constricted Glow Discharge nitrogen plasma source. When bismuth was used as a surfactant, two-dimensional gallium nitride crystal sizes ranging between 10 .mu.m and 20 .mu.m were observed. This is 20 to 40 times larger than crystal sizes observed when GaN films were grown under similar circumstances but without bismuth. It is thought that the observed increase in crystal size is due bismuth inducing an increased surface diffusion coefficient for gallium. The calculated value of 4.7.times.10.sup.-7 cm.sup.2 /sec. reveals a virtual substrate temperature of 1258 K which is 260 degrees higher than the actual one.

  20. Bismuth ferrite as low-loss switchable material for plasmonic waveguide modulator.

    Science.gov (United States)

    Babicheva, Viktoriia E; Zhukovsky, Sergei V; Lavrinenko, Andrei V

    2014-11-17

    We propose new designs of plasmonic modulators, which can be used for dynamic signal switching in photonic integrated circuits. We study performance of a plasmonic waveguide modulator with bismuth ferrite as a tunable material. The bismuth ferrite core is sandwiched between metal plates (metal-insulator-metal configuration), which also serve as electrodes. The core changes its refractive index by means of partial in-plane to out-of-plane reorientation of ferroelectric domains in bismuth ferrite under applied voltage. As a result, guided modes change their propagation constant and absorption coefficient, allowing light modulation in both phase and amplitude control schemes. Due to high field confinement between the metal layers, existence of mode cut-offs for certain values of the core thickness, and near-zero material losses in bismuth ferrite, efficient modulation performance is achieved. For the phase control scheme, the π phase shift is provided by a 0.8-μm long device with propagation losses 0.29 dB/μm. For the amplitude control scheme, up to 38 dB/μm extinction ratio with 1.2 dB/μm propagation loss is predicted.

  1. Effect of bismuth citrate, lactose, and organic acid on necrotic enteritis in broilers

    Science.gov (United States)

    Clostridium perfringens – associated necrotic enteritis causes significant losses and increased morbidity in poultry. The objective of this study was to evaluate the effect of bismuth citrate and acidifiers on the development of necrotic enteritis in broilers. The first study was a dose response t...

  2. Bio-assisted synthesis and characterization of nanostructured bismuth (III) sulphide using Clostridium acetobutylicum

    Energy Technology Data Exchange (ETDEWEB)

    Kamaraj, Sathish Kumar; Venkatachalam, Ganesh; Arumugam, Palaniappan; Berchmans, Sheela, E-mail: sheelaberchmans@yahoo.com

    2014-02-14

    Nanostructured bismuth (III) sulphide is synthesized at room temperature using a hydrogen sulphide producing microorganism namely Clostridium acetobutylicum. On contrary to chemical routes involving both the high and room temperature methods, the present experimental procedure involves a bio-assisted approach. This method is free from the usage of toxic and hazardous chemicals making it an environment friendly route. The synthesized bismuth sulphide is characterized using transmission electron microscope (TEM), powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry (CV). From our experiments we find that bismuth sulphide produced using this bio-assisted approach exhibits a hexagonal shaped plate-like structures and is stabilized by the extracellular proteins present in the culture medium. - Graphical abstract: A green chemistry approach towards the synthesis of bismuth (III) sulphide nanostructures at room temperature using a hydrogen sulphide producing microorganism namely, Clostridium acetobutylicum is demonstrated. - Highlights: • Environmentally benign (greener) route towards synthesis of Bi{sub 2}S{sub 3} nanostructures. • Bio-assisted synthesis of Bi{sub 2}S{sub 3} at room temperature using Clostridium acetobutylicum. • Extracellular proteins in H{sub 2}S producing microorganism as stabilizer for Bi{sub 2}S{sub 3} NPs. • Hexagonal platelets of Bi{sub 2}S{sub 3} possessing an orthorhombic crystalline structure.

  3. Controlled growth of bismuth nanoparticles by electron beam irradiation in TEM

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seon Ho [College of Environment and Applied Chemistry, Kyung Hee University, Yongin 449-701 (Korea, Republic of); Choi, Young-Suk [Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY 11973 (United States); Kang, Kyongha [Materials Science Department, Brookhaven National Laboratory, Upton, NY 11973 (United States)]. E-mail: kkang@bnl.gov; Yang, Sung Ik [College of Environment and Applied Chemistry, Kyung Hee University, Yongin 449-701 (Korea, Republic of)]. E-mail: siyang@khu.ac.kr

    2007-01-16

    In situ nanometer-sized bismuth particles were synthesized by irradiation of the electron beam in the TEM. The size of the crystalline Bi nanoparticles could be controlled by adjusting the irradiation time of the electron beam. Characterization of TEM reveals that the Bi nanoparticles exist in rhombic structure, same as to bulk Bi.

  4. Controlled oxidative synthesis of Bi nanoparticles and emission centers in bismuth glass nanocomposites for photonic application

    Science.gov (United States)

    Singh, Shiv Prakash; Karmakar, Basudeb

    2011-09-01

    Here we demonstrate an oxidative process to control metallic bismuth (Bi 0) nanoparticles (NPs) creation in bismuth glass nanocomposites by using K 2S 2O 8 as oxidant and enhanced transparency of bismuth glasses. Formation of Bi 0 NPs has been monitored by their distinct surface plasmon resonance (SPR) band at 460 nm in the UV-visible absorption spectra. It is further confirmed by the transmission electron microscopy (TEM) images which disclose the formation of spherical Bi 0 NPs whereas the selected area electron diffraction (SAED) pattern reveals their crystalline rhombohedral phase. These glasses are found to exhibit visible and near infrared (NIR) luminescence bands at 630 and 843 nm respectively on excitation at 460 nm of the SPR band. It is realized that the luminescence center of bismuth species is an uncertain issue, however, it is reasonable to consider that the emission band at 630 nm is due to the combination of 2D 5/2 → 4S 3/2 of Bi 0 and 2P 3/2 (1) → 2P 1/2 of Bi 2+ transitions, and that of NIR emission band at 843 nm is attributed to the 2D 3/2 → 4S 3/2 of Bi 0 transition.

  5. The antimicrobial effects and metabolomic footprinting of carboxyl-capped bismuth nanoparticles against Helicobacter pylori.

    Science.gov (United States)

    Nazari, P; Dowlatabadi-Bazaz, R; Mofid, M R; Pourmand, M R; Daryani, N E; Faramarzi, M A; Sepehrizadeh, Z; Shahverdi, A R

    2014-01-01

    Organic salts of bismuth are currently used as antimicrobial agents against Helicobacter pylori. This study evaluated the antibacterial effect of elemental bismuth nanoparticles (Bi NPs) using a serial agar dilution method for the first time against different clinical isolates and a standard strain of H. pylori. The Bi NPs were biologically prepared and purified by a recently described method and subjected to further characterization by infrared spectroscopy and anti-H. pylori evaluation. Infrared spectroscopy results showed the presence of carboxyl functional groups on the surface of biogenic Bi NPs. These biogenic nanoparticles showed good antibacterial activity against all tested H. pylori strains. The resulting MICs varied between 60 and 100 μg/ml for clinical isolates of H. pylori and H. pylori (ATCC 26695). The antibacterial effect of bismuth ions was also tested against all test strains. The antimicrobial effect of Bi ions was lower than antimicrobial effect of bismuth in the form of elemental NPs. The effect of Bi NPs on metabolomic footprinting of H. pylori was further evaluated by (1)H NMR spectroscopy. Exposure of H. pylori to an inhibitory concentration of Bi NPs (100 μg/ml) led to release of some metabolites such as acetate, formic acid, glutamate, valine, glycine, and uracil from bacteria into their supernatant. These findings confirm that these nanoparticles interfere with Krebs cycle, nucleotide, and amino acid metabolism and shows anti-H. pylori activity.

  6. Microwave-assisted facile and rapid Friedel-Crafts benzoylation of arenes catalysed by bismuth trifluoromethanesulfonate

    DEFF Research Database (Denmark)

    Tran, Phoung Hoang; Hansen, Poul Erik; Pham, Thuy Than;

    2014-01-01

    The catalytic activity of metal triflates was investigated in Friedel–Crafts benzoylation under microwave irradiation. Friedel–Crafts benzoylation with benzoyl chloride of a variety of arenes containing electron-rich and electron-poor rings using bismuth triflate under microwave irradiation is de...

  7. Selective Nitration of Aromatic Compounds with Bismuth Subnitrate and Thionyl Chloride

    Directory of Open Access Journals (Sweden)

    Hussni A. Muathen

    2003-07-01

    Full Text Available Bismuth subnitrate/thionyl chloride have been found to be an efficient combination of reagents for nitration of a wide range of aromatic compounds in dichloromethane. Phenols, in particular, were easily mononitrated and dinitrated with the reagents by controlling the stoichiometry,

  8. Selective oxidation of propylene to acrolein by hydrothermally synthesized bismuth molybdates

    DEFF Research Database (Denmark)

    Schuh, Kirsten; Kleist, Wolfgang; Høj, Martin

    2014-01-01

    Hydrothermal synthesis has been used as a soft chemical method to prepare bismuth molybdate catalysts for the selective oxidation of propylene to acrolein. All obtained samples displayed a plate-like morphology, but their individual aspect ratios varied with the hydrothermal synthesis conditions...

  9. Electrodeposition of bismuth telluride thermoelectric films from a nonaqueous electrolyte using ethylene glycol

    NARCIS (Netherlands)

    Nguyen, H.P.; Wu, M.; Su, J.; Vullers, R.J.M.; Vereecken, P.M.; Fransaer, J.

    2012-01-01

    Ethylene glycol was studied as an electrolyte for the electrodeposition of thermoelectric bismuth telluride films by cyclic voltammetry, rotating ring disk electrode and electrochemical quartz crystal microbalance (EQCM). The reduction of both Bi3+ and Te4+ ions proceeds in one step without the form

  10. Thickness dependence of oxygen permeation through erbia-stabilized bismuth oxide-silver composites

    NARCIS (Netherlands)

    Chen, C.S.; Kruidhof, H.; Bouwmeester, H.J.M.; Verweij, H.; Burggraaf, A.J.

    1997-01-01

    Oxygen permeation measurements were performed on erbia-stabilized bismuth oxide-silver (40 v/o) composite membranes in the range of thickness of 1.60–0.23 mm and temperature of 850–650 °C. Air was fed at one side of the membranes while permeated oxygen on the other side was swept away with helium. A

  11. Bismuth oxide based ceramics with improved electrical and mechanical properties: Part II. Structural and mechanical properties

    NARCIS (Netherlands)

    Kruidhof, H.; Seshan, K.; Velde, van de G.M.H.; Vries, de K.J.; Burggraaf, A.J.

    1988-01-01

    Coprecipitation as a method of preparation for bismuth oxides based ceramics yields relatively strong and machineable materials in comparison with the solid state reaction. Compositions within the system (1−x)Bi2O3|xEr2O3 containing up to twenty five mole percent of erbium oxide show a slow transiti

  12. Dynamic spatial structure of spontaneous beams in photorefractive bismuth sillicon oxide

    DEFF Research Database (Denmark)

    Buchhave, Preben; Lyuksyutov, S.; Vasnetsov, M.

    1996-01-01

    We report the domain structure of spontaneously occurring beams (subharmonics) in photorefractive bismuth silicon oxide with an applied electric field from 1 to 6 kV/cm and a running grating. The subharmonic beams are generated in a pattern of domains that evolve dynamically as they move through...

  13. A sensitive fluorescence quenching method for determination of bismuth with tiron

    Energy Technology Data Exchange (ETDEWEB)

    Taher, Mohammad Ali; Rahimi, Mina [Department of Chemistry, Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of); Fazelirad, Hamid, E-mail: hamidfazelirad@gmail.com [Department of Chemistry, Shahid Bahonar University of Kerman, Kerman (Iran, Islamic Republic of); Department of Chemistry, Science and Research Branch, Islamic Azad University, Yazd (Iran, Islamic Republic of); Young Researchers Society, Shahid Bahonar University of Kerman, P.O. Box 76175-133, Kerman (Iran, Islamic Republic of)

    2014-01-15

    We describe a fluorescence quenching method for determination of bismuth with tiron. The method is based on the reaction of tiron by bismuth(III) in acidic media. The influence of variables such as the pH, type of buffer, tiron concentration, reaction time and temperature were investigated. Under optimized conditions, the fluorescence quenching extent is proportional to the concentration of bismuth for Bi–tiron system at the range 0.13–2.09 μg mL{sup −1} and the detection limit is 0.05 μg mL{sup −1}. The proposed sensor presented good repeatability, evaluated in terms of relative standard deviation (R.S.D.=±0.498%) for 11 replicates. This sensitive, rapid and accurate method has been successfully applied to the determination of trace bismuth(III) in water and hair samples and certified reference materials. -- Highlights: • No previous paper report on use of fluorescence quenching for determination of Bi. • Fluorescence quenching of trion is a sensitive method for determination of Bi(III). • Under the optimum conditions the detection limit is very low (0.05 μg mL{sup −1}). • The procedure is simple and safe and has high tolerance limit to interferences.

  14. Structural Engineering of Vacancy Defected Bismuth Tellurides for Thermo-electric Applications

    Science.gov (United States)

    Termentzidis, K.; Pokropivny, A.; Xiong, S.-Y.; Chumakov, Y.; Cortona, P.; Volz, S.

    2012-10-01

    Molecular Dynamics and ab-initio simulations are used to find the most stable stoichiometries of Bismuth Tellurides with vacancy defects. The interest is to decrease the thermal conductivity of these compounds a key point to achieve high figure of merits. A reduction of 70% of the thermal conductivity is observed with Te vacancies of only 5%.

  15. Bismuth-embedded SBA-15 mesoporous silica for radioactive iodine capture and stable storage

    Science.gov (United States)

    Yang, Jae Hwan; Cho, Yong-Jun; Shin, Jin Myeong; Yim, Man-Sung

    2015-10-01

    Efficient capture and stable storage of the long-lived iodine-129 (129I), released as off-gas from nuclear fuel reprocessing, have been of significant concern in the waste management field. In this study, bismuth-embedded SBA-15 mesoporous silica was firstly applied for iodine capture and storage. SBA-15 was functionalized with thiol (-SH) groups, followed by bismuth adsorption with Bi-S bonding, which was thermally treated to form Bi2S3 within SBA-15. The bismuth-embedded SBA-15s demonstrated high iodine loading capacities (up to 540 mg-I/g-sorbent), which benefitted from high surface area and porosity of SBA-15 as well as the formation of thermodynamically stable BiI3 compound. Iodine physisorption was effectively suppressed due to the large pores present in SBA-15, resulting in chemisorption as a main mechanism for iodine confinement. Furthermore, a chemically durable iodine-bearing material was made with a facile post-sorption process, during which the iodine-incorporated phase was changed from BiI3 to chemically durable Bi5O7I. Thus, our results showed that both efficient capture and stabilization of 129I would be possible with the bismuth-embedded SBA-15, in contrast to other sorbents mainly focused on iodine capture.

  16. Structural Engineering of Vacancy Defected Bismuth Tellurides for Thermo-electric Applications

    Directory of Open Access Journals (Sweden)

    Chumakov Y.

    2012-10-01

    Full Text Available Molecular Dynamics and ab-initio simulations are used to find the most stable stoichiometries of Bismuth Tellurides with vacancy defects. The interest is to decrease the thermal conductivity of these compounds a key point to achieve high figure of merits. A reduction of 70% of the thermal conductivity is observed with Te vacancies of only 5%.

  17. 75 FR 34360 - Listing of Color Additives Exempt From Certification; Bismuth Citrate; Confirmation of Effective...

    Science.gov (United States)

    2010-06-17

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 73 Listing of Color Additives Exempt From... March 26, 2010. The final rule amended the color additive regulations by increasing the permitted use level of bismuth citrate as a color additive in cosmetics intended for coloring hair on the scalp....

  18. Response of Ag Thick Film Microstripline due to Superstrate Strontium Substituted Bismuth Manganites

    Directory of Open Access Journals (Sweden)

    S.N. Mathad

    2014-06-01

    Full Text Available The purpose of this paper is to describe the use of strontium-substituted bismuth manganites bulk ceramic superstrate on Ag thick film microstripline, to modify its response and measure complex permittivity as a function of strontium. Bismuth strontium manganites (Bi1 − xSrxMnO3 have been synthesized by solid state sintering technique. The perturbation obtained in the transmittance and reflectance of thick film microstripline due to the Bi1 − xSrxMnO3 (0.20  x  0.50 overlay has been used to obtain the permittivity at microwave frequencies in X and Ku band range. Due to the overlay of Bismuth strontium manganites (BSM pellets a substantial increase in the effective dielectric constant was observed in X band more compared to Ku band. The in-touch overlay method provides ease loading and unloading. The perturbation obtained in the transmittance and reflectance of thick film microstripline due to the bismuth strontium manganites overlay has been used to obtain the permittivity.

  19. 40 CFR 471.10 - Applicability; description of the lead-tin-bismuth forming subcategory.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Applicability; description of the lead-tin-bismuth forming subcategory. 471.10 Section 471.10 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS NONFERROUS METALS FORMING AND METAL...

  20. Radiation Emitting Product Corrective Actions and Recalls

    Data.gov (United States)

    U.S. Department of Health & Human Services — This database provides descriptions of radiation-emitting products that have been recalled under an approved corrective action plan to remove defective and...

  1. Radiation-emitting Electronic Product Codes

    Data.gov (United States)

    U.S. Department of Health & Human Services — This database contains product names and associated information developed by the Center for all products, both medical and non-medical, which emit radiation. It...

  2. Dose reduction in CT using bismuth shielding: measurements and Monte Carlo simulations.

    Science.gov (United States)

    Chang, Kyung-Hwan; Lee, Wonho; Choo, Dong-Myung; Lee, Choon-Sik; Kim, Youhyun

    2010-03-01

    In this research, using direct measurements and Monte Carlo calculations, the potential dose reduction achieved by bismuth shielding in computed tomography was evaluated. The patient dose was measured using an ionisation chamber in a polymethylmethacrylate (PMMA) phantom that had five measurement points at the centre and periphery. Simulations were performed using the MCNPX code. For both the bare and the bismuth-shielded phantom, the differences of dose values between experiment and simulation were within 9%. The dose reductions due to the bismuth shielding were 1.2-55% depending on the measurement points, X-ray tube voltage and the type of shielding. The amount of dose reduction was significant for the positions covered by the bismuth shielding (34 - 46% for head and 41 - 55% for body phantom on average) and negligible for other peripheral positions. The artefact on the reconstructed images were minimal when the distance between the shielding and the organs was >1 cm, and hence the shielding should be selectively located to protect critical organs such as the eye lens, thyroid and breast. The simulation results using the PMMA phantom was compared with those using a realistically voxelised phantom (KTMAN-2). For eye and breast, the simulation results using the PMMA and KTMAN-2 phantoms were similar with each other, while for thyroid the simulation results were different due to the discrepancy of locations and the sizes of the phantoms. The dose reductions achieved by bismuth and lead shielding were compared with each other and the results showed that the difference of the dose reductions achieved by the two materials was less than 2-3%.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-12-15

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

  4. Hall Plateaus at magic angles in ultraquantum Bismuth

    Science.gov (United States)

    Benoît, Fauqué.

    2009-03-01

    The behaviour of a three-dimensional electron gas in the presence of a magnetic field strong enough to put all carriers in the first Landau level (i.e. beyond the quantum limit) is a longstanding question of theoretical condensed matter physics [1]. This issue has been recently explored by two high-field experiments on elemental semi-metal Bismuth. In a first study of transport coefficients (which are dominated by hole-like carriers), the Nernst coefficient presented three unexpected maxima that are concomitant with quasi-plateaux in the Hall coefficient [2]. In a second series of experiments, torque magnetometry (which mainly probes the three Dirac valley electron pockets) detected a field-induced phase transition [3]. The full understanding of the electron and hole behaviours above the quantum limit of pure Bi is therefore still under debate. In this talk, we will present our measurement of the Hall resistivity and torque magnetometry with magnetic field up to 31 T and rotating in the trigonal-bisectrix plane [4]. The Hall response is dominated by the hole pockets according to its sign as well as the period and the angular dependence of its quantum oscillations. In the vicinity of the quantum limit, it presents additional anomalies which are the fingerprints of the electron pockets. We found that for particular orientations of the magnetic field (namely ``magic angles''), the Hall response becomes field-independent within the experimental resolution around 20T. This drastic dependence of the plateaux on the field orientation provides strong constraints for theoretical scenarios. [4pt] [1] Bertrand I. Halperin, Japanese Journal of Applied Physics, 26, Supplement 26-3 (1987).[0pt] [2] Kamran Behnia, Luis Balicas, Yakov Kopelevich, Science, 317, 1729 (2008).[0pt] [3] Lu Li, J. G. Checkelsky, Y. S. Hor, C. Uher, A. F. Hebard, R. J. Cava, and N. P. Ong , Science, 321, 5888 (2008).[0pt] [4] Benoît Fauqu'e, Luis Balicas, Ilya Sheikin, Jean Paul Issi and Kamran Behnia

  5. 从铅阳极泥中湿法提取铋、锑试验研究%Extraction of Bismuth and Antimony by Wet-process From Lead Anode Mud

    Institute of Scientific and Technical Information of China (English)

    贾辉; 王兴; 崔家友; 侯绍彬; 林浩

    2014-01-01

    Leaching of bismuth and antimony from lead anode mud oxidized at high temperature using hydrochloric acid as leaching agent ,ferric chloride as oxidant ,sodium chloride to provide more chloride ions was investigated .The effects of oxidizing temperature of lead anode mud ,hydrochloric acid concentration ,leaching temperature ,reaction time ,ratio between liquid volume and solid mass ,the amount of ferric chloride and sodium chloride on leaching of bismuth and antimony were examined . The experimental results show that the pretreatment for lead anode slime has a greater influence on the leaching of bismuth and antimony .Under the conditions of hydrochloric acid concentration of 5 mol/L ,ratio betw een liquid volume and solid mass of 5∶1 ,leaching temperature of 80 ℃ ,reaction time of 3 h ,ferric chloride concentration of 10 g/L ,sodium chloride concentration of 45 g/L ,the leaching of bismuth and antimony reach 99 .44% and 99 .69% respectively for the lead anode mud oxidized at 200 ℃ and through 200 mesh sieve .%介绍了以三氯化铁作氧化剂,氯化钠提供氯离子,用盐酸从高温氧化后的铅阳极泥中浸出铋、锑,考察了氧化温度、盐酸浓度、浸出温度、反应时间、液固体积质量比、三氯化铁和氯化钠用量对铋、锑浸出率的影响。试验结果表明:铅阳极泥预处理对铋、锑浸出率影响较大;铅阳极泥粉磨过200目筛,在氧化温度220℃、盐酸浓度5 mol/L、液固体积质量比5∶1、反应温度80℃、反应时间3 h、三氯化铁质量浓度10 g/L、氯化钠质量浓度45 g/L条件下,铋、锑浸出率分别为99.44%和99.69%,浸出效果较好。

  6. Experimental study on the effects of bismuth subgallate on the inflammatory process and angiogenesis of the oral mucosa

    Directory of Open Access Journals (Sweden)

    Eduardo Vieira Couto

    2016-02-01

    Full Text Available ABSTRACT INTRODUCTION: Bismuth subgallate is a salt derived from heavy metal. The aim of this study was to evaluate the effect of this salt on some phases of healing. OBJECTIVES: To assess the effect of subgallate on mucosa and to evaluate the association between the use of bismuth subgallate and neogenesis of vessels in oral mucosal wounds. METHODS: This was a prospective and experimental study. This study used sixty rats, which were divided into control and experimental groups. The animals were submitted to a surgical procedure, which caused oral mucosal injury. A saline solution was applied on the wound of the control group, and in the experimental group, a solution of bismuth subgallate was administrated. RESULTS: The experimental group showed greater inflammatory reaction with increasing monomorphic proliferation. There was increased vessel proliferation in the control group. CONCLUSION: Bismuth subgallate had a negative influence on the healing process, delaying the rate of new vessel formation and optimal wound healing.

  7. Recent progress of bismuth-containing photocatalysts%含铋光催化材料的研究进展

    Institute of Scientific and Technical Information of China (English)

    王伟华; 叶红齐; 覃涛; 刘宣业; 黄辉; 赵炜康; 朱坤杰

    2014-01-01

    Bismuth-containing photocatalysts can be used in many fields because of narrow band gap and ability of adsorbing visible light. In this paper , the latest research status and progress of bismuth-containing photocatalysts are reviewed. Bismuth oxide , halide bismuth oxide , bismuth titanate,bismuth tungstate,bismuth vanadate,bismuth molybdate and bismuth ferrite are introduced and the methods of improving photocatalytic performance are highlighted,including improvement of synthesis methods,photocatalysts doping and preparation of photocatalyst composites. Finally,the research directions of bismuth-containing photocatalysts are presented,aimed at improving overall performance and realizing industrial application of bismuth-containing photocatalysts , such as preparing multi-doped photocatalysts,multiple photocatalyst composites and supported catalysts.%含铋光催化材料因其能吸收可见光、催化活性高而具有广阔的应用前景。本文主要回顾了含铋光催化材料近年来的研究概况,详细介绍了铋氧化物、卤氧化铋及钛酸铋、钨酸铋、钒酸铋、钼酸铋、铁酸铋等光催化剂的结构、制备和光催化性能,重点对光催化性能的改进方法进行了综述,包括制备方法的改良、催化剂的掺杂改性及复合催化剂的制备等;最后针对进一步提高光催化剂整体性能、实现工业化应用两点,提出了未来可以利用多元元素掺杂、多元半导体复合进行改性和负载于某些载体制备整体催化剂进行改良的观点。

  8. Production of α-particle emitting 211At using 45 MeV α-beam

    Science.gov (United States)

    Kim, Gyehong; Chun, Kwonsoo; Park, Sung Ho; Kim, Byungil

    2014-06-01

    Among the α-particle emitting radionuclides, 211At is considered to be a promising radionuclide for targeted cancer therapy due to its decay properties. The range of alpha particles produced by the decay of 211At are less than 70 µm in water with a linear energy transfer between 100 and 130 keV µm-1, which are about the maximum relative biological effectiveness for heavy ions. It is important to note that at the present time, only a few of cyclotrons routinely produce 211At. The direct production method is based on the nuclear reactions 209Bi(α,2n)211At. Production of the radionuclide 211At was carried out using the MC-50 cyclotron at the Korea Institute of Radiological and Medical Sciences (KIRAMS). To ensure high beam current, the α-beam was extracted with an initial energy of 45 MeV, which was degraded to obtain the appropriate α-beam energy. The calculations of beam energy degradation were performed utilizing the MCNPX. Alumina-baked targets were prepared by heating the bismuth metal powder onto a circular cavity in a furnace. When using an Eα, av of 29.17 MeV, the very small contribution of 210At confirms the right choice of the irradiation energy to obtain a pure production of 211At isotope.

  9. EQCM Study of Influence of Anion Nature on Electrochemical Reduction of Bismuth Sulfide in Nickel Plating Solution

    OpenAIRE

    Loreta TAMAŠAUSKAITĖ-TAMAŠIŪNAITĖ; Leonas NARUŠKEVIČIUS; Žielienė, Albina; Birutė ŠIMKŪNAITĖ-STANYNIENĖ; Genovaitė VALIULIENĖ; Aloyzas SUDAVIČIUS

    2011-01-01

    The influence of anion nature on the reduction of bismuth sulfide film deposited on gold using the successive ionic layer adsorption and reaction method in solutions containing Ni2+ ions has been investigated by electrochemical quartz crystal microbalance combined with cyclic voltammetry and X-ray photoelectron spectroscopy. It has been determined that the reduction of bismuth sulfide film in the nickel plating solution depends on the anion nature: larger cathodic current and mass changes (Dƒ...

  10. 钒酸铋掺杂体系的研究进展%DEVELOPMENT OF DOPED BISMUTH VANADATE MATERIALS

    Institute of Scientific and Technical Information of China (English)

    朱振峰; 张炼

    2012-01-01

    This paper mainly introduces development of bismuth vanadate doped with rare earth elements,transition elements,carbon group elements and other elements and put forward a development direction of bismuth vanadate materials in the future.%介绍了稀土元素、过渡元素、碳族元素和其它元素的钒酸铋掺杂体系,并对未来的发展方向做出展望。

  11. Bismuth Based Hybrid Perovskites A3Bi2 I9 (A: Methylammonium or Cesium) for Solar Cell Application.

    Science.gov (United States)

    Park, Byung-Wook; Philippe, Bertrand; Zhang, Xiaoliang; Rensmo, Håkan; Boschloo, Gerrit; Johansson, Erik M J

    2015-11-18

    Low-toxic bismuth-based perovskites are prepared for the possible replacement of lead perovskite in solar cells. The perovskites have a hexagonal crystalline phase and light absorption in the visible region. A power conversion efficiency of over 1% is obtained for a solar cell with Cs3 Bi2 I9 perovskite, and it is concluded that bismuth perovskites have very promising properties for further development in solar cells.

  12. SEPARATION OF POLONIUM, PROTACTINIUM OR MIXTURES THEREOF IN AQUEOUS SOLUTION FROM BISMUTH, LEAD, ZIRCONIUM AND/OR COLUMBIUM VALUES

    Science.gov (United States)

    Van Winkle, Q.; Kraus, K.A.

    1959-10-27

    A process is presented for separating polonium, protactinium, or mixtures thereof in aqueous solution from bismuth, zirconium, lead, and niobium values contained in the solution. The method comprises providing hydrochloric acid in the solution in a concentration of at least 5N. contacting the aqueous solution with a substantially waterimmiscible organic solvent such as diisopropyl ketone, and separating the aqueous phase containing the bismuth, zirconium, lead, and niobium from the organic extract phase containing the polonium, protactinium, or mixture thereof.

  13. Copper(I)-catalyzed cycloaddition of bismuth(III) acetylides with organic azides: synthesis of stable triazole anion equivalents.

    Science.gov (United States)

    Worrell, Brady T; Ellery, Shelby P; Fokin, Valery V

    2013-12-02

    Fully loaded: Readily accessible and shelf-stable 1-bismuth(III) acetylides react rapidly and regiospecifically with organic azides in the presence of a copper(I) catalyst. The reaction tolerates many functional groups and gives excellent yields of the previously unreported 5-bismuth triazolides. This uniquely reactive intermediate is functionalized under mild reaction conditions to give fully substituted 1,2,3-triazoles. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Externally Wetted Ionic Liquid Thruster

    Science.gov (United States)

    Lozano, P.; Martinez-Sanchez, M.; Lopez-Urdiales, J. M.

    2004-10-01

    This paper presents initial developments of an electric propulsion system based on ionic liquid ion sources (ILIS). Propellants are ionic liquids, which are organic salts with two important characteristics; they remain in the liquid state at room temperature and have negligible vapor pressure, thus allowing their use in vacuum. The working principles of ILIS are similar to those of liquid metal ion sources (LMIS), in which a Taylor cone is electrostatically formed at the tip of an externally wetted needle while ions are emitted directly from its apex. ILIS have the advantage of being able to produce negative ions that have similar masses than their positive counterparts with similar current levels. This opens up the possibility of achieving plume electrical neutrality without electron emitters. The possible multiplexing of these emitters is discussed in terms of achievable thrust density for applications other than micro-propulsion.

  15. A metastable liquid melted from a crystalline solid under decompression

    Science.gov (United States)

    Lin, Chuanlong; Smith, Jesse S.; Sinogeikin, Stanislav V.; Kono, Yoshio; Park, Changyong; Kenney-Benson, Curtis; Shen, Guoyin

    2017-01-01

    A metastable liquid may exist under supercooling, sustaining the liquid below the melting point such as supercooled water and silicon. It may also exist as a transient state in solid–solid transitions, as demonstrated in recent studies of colloidal particles and glass-forming metallic systems. One important question is whether a crystalline solid may directly melt into a sustainable metastable liquid. By thermal heating, a crystalline solid will always melt into a liquid above the melting point. Here we report that a high-pressure crystalline phase of bismuth can melt into a metastable liquid below the melting line through a decompression process. The decompression-induced metastable liquid can be maintained for hours in static conditions, and transform to crystalline phases when external perturbations, such as heating and cooling, are applied. It occurs in the pressure–temperature region similar to where the supercooled liquid Bi is observed. Akin to supercooled liquid, the pressure-induced metastable liquid may be more ubiquitous than we thought. PMID:28112152

  16. A bismuth activation counter for high sensitivity pulsed 14 MeV neutrons

    Science.gov (United States)

    Burns, E. J. T.; Thacher, P. D.; Hassig, G. J.; Decker, R. D.; Romero, J. A.; Barrett, K. P.

    2011-08-01

    We have built a fast neutron bismuth activation counter that measures activation counts from pulsed 14-MeV neutron generators for incident neutron fluences between 30 and 300 neutrons/cm2 at 15.2 cm (6 in.). The activation counter consists of a large bismuth germanate (BGO) detector surrounded by a bismuth metal shield in front of and concentric with the cylindrical detector housing. The 14 MeV neutrons activate the 2.6-millisecond (ms) isomer in the shield and the detector by the reaction 209Bi (n,2nγ) 208mBi. The use of millisecond isomers and activation counting times minimizes the background from other activated materials and the environment. In addition to activation, the bismuth metal shields against other outside radiation sources. We have tested the bismuth activation counter, simultaneously, with two data acquisition systems (DASs) and both give similar results. The two-dimensional (2D) DAS and three dimensional (3D) DAS both consist of pulse height analysis (PHA) systems that can be used to discriminate against gamma radiations below 300 keV photon energy, so that the detector can be used strictly as a counter. If the counting time is restricted to less than 25 ms after the neutron pulse, there are less than 10 counts of background for single pulse operation in all our operational environments tested so far. High-fluence neutron generator operations are restricted by large dead times and pulse height saturation. When we operate our 3D DAS PHA system in list mode acquisition (LIST), real-time corrections to dead time or live time can be made on the scale of 1 ms time windows or dwell times. The live time correction is consistent with nonparalyzable models for dead time of 1.0±0.2 μs for our 3D DAS and 1.5±0.3 μs for our 2D DAS dominated by our fixed time width analog to digital converters (ADCs). With the same solid angle, we have shown that the bismuth activation counter has a factor of 4 increase in sensitivity over our lead activation counter

  17. Three-Component One-Pot Synthesis of Novel Benzo[b]1,8-naphthyridines Catalyzed by Bismuth(III Chloride

    Directory of Open Access Journals (Sweden)

    Tangali R. Ravikumar Naik

    2008-01-01

    Full Text Available A novel and efficient three-component one-pot synthesis of benzo[b]1,8-naphthyridines by 2-amino-4-methylquinoline, aromatic aldehydes, and malononitrile was done. The reaction was catalyzed by an acidic Bismuth(III chloride, functionalized Bismuth(III chloride, at room temperature to give various benzo[b]1,8-naphthyridines in high yields. The Bismuth(III chloride is an environmentally friendly catalyst.

  18. Confocal microscopic analysis of optical crosstalk from micro-pixel light-emitting diodes

    OpenAIRE

    2015-01-01

    Self-illuminating displays comprising two-dimensional arrays of micro-emitters are superior over conventional backlight-illuminated liquid-crystal displays (LCD) in many aspects, including lower power consumptions, thinner profiles, higher image contrasts, wider viewing angles, and broader operating temperatures. There still are several technical challenges prevent self-illuminating organic light-emitting diodes (OLEDs) from becoming a dominant commercial product in the field of image display...

  19. Characterization, Leaching, and Filtration Testing for Bismuth Phosphate Sludge (Group 1) and Bismuth Phosphate Saltcake (Group 2) Actual Waste Sample Composites

    Energy Technology Data Exchange (ETDEWEB)

    Lumetta, Gregg J.; Buck, Edgar C.; Daniel, Richard C.; Draper, Kathryn; Edwards, Matthew K.; Fiskum, Sandra K.; Hallen, Richard T.; Jagoda, Lynette K.; Jenson, Evan D.; Kozelisky, Anne E.; MacFarlan, Paul J.; Peterson, Reid A.; Shimskey, Rick W.; Sinkov, Sergey I.; Snow, Lanee A.

    2009-02-19

    A testing program evaluating actual tank waste was developed in response to Task 4 from the M-12 External Flowsheet Review Team (EFRT) issue response plan.() The test program was subdivided into logical increments. The bulk water-insoluble solid wastes that are anticipated to be delivered to the Waste Treatment and Immobilization Plant (WTP) were identified according to type such that the actual waste testing could be targeted to the relevant categories. Eight broad waste groupings were defined. Samples available from the 222S archive were identified and obtained for testing. The actual waste-testing program included homogenizing the samples by group, characterizing the solids and aqueous phases, and performing parametric leaching tests. Two of the eight defined groups—bismuth phosphate sludge (Group 1) and bismuth phosphate saltcake (Group 2)—are the subjects of this report. The Group 1 waste was anticipated to be high in phosphorus and was implicitly assumed to be present as BiPO4 (however, results presented here indicate that the phosphate in Group 1 is actually present as amorphous iron(III) phosphate). The Group 2 waste was also anticipated to be high in phosphorus, but because of the relatively low bismuth content and higher aluminum content, it was anticipated that the Group 2 waste would contain a mixture of gibbsite, sodium phosphate, and aluminum phosphate. Thus, the focus of the Group 1 testing was on determining the behavior of P removal during caustic leaching, and the focus of the Group 2 testing was on the removal of both P and Al. The waste-type definition, archived sample conditions, homogenization activities, characterization (physical, chemical, radioisotope, and crystal habit), and caustic leaching behavior as functions of time, temperature, and hydroxide concentration are discussed in this report. Testing was conducted according to TP-RPP-WTP-467.

  20. Quantitative method for measuring heat flux emitted from a cryogenic object

    Science.gov (United States)

    Duncan, Robert V.

    1993-01-01

    The present invention is a quantitative method for measuring the total heat flux, and of deriving the total power dissipation, of a heat-fluxing object which includes the steps of placing an electrical noise-emitting heat-fluxing object in a liquid helium bath and measuring the superfluid transition temperature of the bath. The temperature of the liquid helium bath is thereafter reduced until some measurable parameter, such as the electrical noise, exhibited by the heat-fluxing object or a temperature-dependent resistive thin film in intimate contact with the heat-fluxing object, becomes greatly reduced. The temperature of the liquid helum bath is measured at this point. The difference between the superfluid transition temperature of the liquid helium bath surrounding the heat-fluxing object, and the temperature of the liquid helium bath when the electrical noise emitted by the heat-fluxing object becomes greatly reduced, is determined. The total heat flux from the heat-fluxing object is determined as a function of this difference between these temperatures. In certain applications, the technique can be used to optimize thermal design parameters of cryogenic electronics, for example, Josephson junction and infra-red sensing devices.

  1. [L'application des radioisotopes a la chromatographie sur colonnes de celluloses substituees-IV L'analyse du mercure et du zinc dans le bismuth].

    Science.gov (United States)

    Muzzarelli, R A; Marcotrigiano, G

    1967-03-01

    The Chromatographic behaviour of nanogram amounts of bismuth has been studied by radioisotope techniques on cellobiose, cellulose and seven substituted celluloses. All celluloses in ethyl ether adsorb bismuth, provided that it is as nitrate, and that excess of nitric acid is avoided. Bismuth can be eluted with thiocyanate in ether-methanol or with hydrochloric acid in methanol, depending on the retention strength of the various functional groups of celluloses. A very simple method of separation of bismuth from mercury over a wide range of concentration is presented.

  2. Recovery of IR luminescence in photobleached bismuth-doped fibers by thermal annealing

    Science.gov (United States)

    Firstov, S. V.; Firstova, E. G.; Alyshev, S. V.; Khopin, V. F.; Riumkin, K. E.; Melkumov, M. A.; Guryanov, A. N.; Dianov, E. M.

    2016-08-01

    The effect of annealing temperature on the luminescent properties of bismuth-doped fibers bleached by 532 nm laser radiation was investigated. The photoluminescence (PL) measurements were performed in pristine and photobleached samples which were thermally annealed at various temperatures ranging from 100 to 900 °C and slowly cooled. We observed that the intensity of the PL band at 1700 nm in the photobleached fibers recovered its pre-bleached level. Moreover, it was shown that a significant increase of the PL level could be achieved using the special annealing regime. Thereby, we obtained the experimental evidence of a thermally activated recovery process of the PL intensity showing that photoinduced changes of PL in bismuth-doped fibers are completely reversible. The mechanism of the thermal recovery of the PL is discussed.

  3. Synthesis and Electrochemical Sensing Toward Heavy Metals of Bunch-like Bismuth Nanostructures

    Directory of Open Access Journals (Sweden)

    Zhang Zhi

    2009-01-01

    Full Text Available Abstract Large-scale bunch-like bismuth (Bi nanostructures were the first time to be synthesized via two-step electrochemical deposition. The growth mechanism of the nanostructures was discussed. Such a designed bunch-like Bi electrode has high sensitivity to detect the heavy metal ions due to its unique three-dimensional structures and strong ability of adsorbing the heavy metal ions. The bunch-like Bi electrode’s detection of heavy metals was statically performed using anodic stripping voltammetry (ASV. The detection in the Pb(II concentration range of 2.5–50 μg/l was also performed. Based on the experimental results, this bunch-like Bi electrode can be considered as an interesting alternative to common mercury electrodes and bismuth film electrodes for possible use in electrochemical studies and electroanalytical applications.

  4. The photorefractive characteristics of bismuth-oxide doped lithium niobate crystals

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Dahuai; Yao, Jiaying [School of Physics, Nankai University, Tianjin 300071 (China); Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072 (China); Kong, Yongfa, E-mail: kongyf@nankai.edu.cn [School of Physics, Nankai University, Tianjin 300071 (China); MOE Key Laboratory of Weak-Light Nonlinear Photonics and TEDA Applied Physics School, Nankai University, Tianjin 300457 (China); R and D Center, Taishan Sports Industry Group, Leling 253600 (China); Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072 (China); Liu, Shiguo [School of Physics, Nankai University, Tianjin 300071 (China); Zhang, Ling; Chen, Shaolin [MOE Key Laboratory of Weak-Light Nonlinear Photonics and TEDA Applied Physics School, Nankai University, Tianjin 300457 (China); Xu, Jingjun [School of Physics, Nankai University, Tianjin 300071 (China); MOE Key Laboratory of Weak-Light Nonlinear Photonics and TEDA Applied Physics School, Nankai University, Tianjin 300457 (China); Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072 (China)

    2015-01-15

    Bismuth-doped lithium niobate (LN:Bi) crystals were grown by Czochralski method and their optical damage resistance, photorefraction, absorption spectra, and defect energy levels were investigated. The experimental results indicate that the photorefractive properties of LN:Bi were enhanced as compared with congruent one, the photorefractive response time was greatly shortened, the photorefractive sensitivity was increased, and the diffraction efficiency of near-stoichiometric LN:Bi (SLN:Bi) reached 31.72% and 49.08% at 532 nm and 488 nm laser, respectively (light intensity of 400 mW/cm{sup 2}). An absorption peak at about 350 nm was observed in the absorption spectrum of LN:Bi. And the defect energy levels simulation indicates new defect levels appear in the forbidden gap of LN:Bi crystals. Therefore bismuth can act as photorefractive centers in LN crystals.

  5. The photorefractive characteristics of bismuth-oxide doped lithium niobate crystals

    Directory of Open Access Journals (Sweden)

    Dahuai Zheng

    2015-01-01

    Full Text Available Bismuth-doped lithium niobate (LN:Bi crystals were grown by Czochralski method and their optical damage resistance, photorefraction, absorption spectra, and defect energy levels were investigated. The experimental results indicate that the photorefractive properties of LN:Bi were enhanced as compared with congruent one, the photorefractive response time was greatly shortened, the photorefractive sensitivity was increased, and the diffraction efficiency of near-stoichiometric LN:Bi (SLN:Bi reached 31.72% and 49.08% at 532 nm and 488 nm laser, respectively (light intensity of 400 mW/cm2. An absorption peak at about 350 nm was observed in the absorption spectrum of LN:Bi. And the defect energy levels simulation indicates new defect levels appear in the forbidden gap of LN:Bi crystals. Therefore bismuth can act as photorefractive centers in LN crystals.

  6. Ab initio lattice dynamics and thermochemistry of layered bismuth telluride (Bi2Te3)

    Science.gov (United States)

    Zurhelle, Alexander F.; Deringer, Volker L.; Stoffel, Ralf P.; Dronskowski, Richard

    2016-03-01

    We present density-functional theory calculations of the lattice dynamics of bismuth telluride, yielding force constants, mean-square displacements and partial densities of phonon states which corroborate and complement previous nuclear inelastic scattering experiments. From these data, we derive an element- and energy-resolved view of the vibrational anharmonicity, quantified by the macroscopic Grüneisen parameter γ which results in 1.56. Finally, we calculate thermochemical properties in the quasiharmonic approximation, especially the heat capacity at constant pressure and the enthalpy of formation for bismuth telluride; the latter arrives at ▵H f (Bi2Te3)  =  -102 kJ mol-1 at 298 K.

  7. Graphite felt modified with bismuth nanoparticles as negative electrode in a vanadium redox flow battery.

    Science.gov (United States)

    Suárez, David J; González, Zoraida; Blanco, Clara; Granda, Marcos; Menéndez, Rosa; Santamaría, Ricardo

    2014-03-01

    A graphite felt decorated with bismuth nanoparticles was studied as negative electrode in a vanadium redox flow battery (VRFB). The results confirm the excellent electrochemical performance of the bismuth modified electrode in terms of the reversibility of the V(3+) /V(2+) redox reactions and its long-term cycling performance. Moreover a mechanism that explains the role that Bi nanoparticles play in the redox reactions in this negative half-cell is proposed. Bi nanoparticles favor the formation of BiHx , an intermediate that reduces V(3+) to V(2+) and, therefore, inhibits the competitive irreversible reaction of hydrogen formation (responsible for the commonly observed loss of Coulombic efficiency of VRFBs). Thus, the total charge consumed during the cathodic sweep in this electrode is used to reduce V(3+) to V(2+) , resulting in a highly reversible and efficient process.

  8. Zero-dimensional nanostructured material with metallic bismuth nanoparticles: a new route for thermoelectrics

    Science.gov (United States)

    Benoit, Roland; Treguer, Mona; Saboungi, Marie-Louise

    2011-03-01

    The thermoelectric figure of merit ZT has so far not exceeded the value ZT=3 need to compete with mechanical energy conversion systems. However, theoretical work has shown that it is possible to reach values of ZT higher than this. One of the most promising routes is nanostructured materials, which offer the opportunity to tailor physical properties such as electrical and heat transport, due to the effects of electron filtering and phonon confinement. Dresselhaus et al. (ref.?) were among the first to show that 2D and 1D structures are capable of reaching ZT values higher than 2. The thermoelectric materials of current interest are in the form of nanotubes, nanodots and, more generally, superlattices composed of a matrix and nanoparticles. In our work we synthesize a periodic network of bismuth nanoparticles in a matrix of mesoporous Si O2 . We find that in this form bismuth transforms from a rhombohedral to a cubic structure, with improved filtering of electrons and phonons.

  9. Gamma-ray shielding and structural properties of barium-bismuth-borosilicate glasses

    Science.gov (United States)

    Bootjomchai, Cherdsak; Laopaiboon, Jintana; Yenchai, Chadet; Laopaiboon, Raewat

    2012-07-01

    The attenuation coefficients of barium-bismuth-borosilicate glasses have been measured for gamma-ray photon energies of 662, 1173 and 1332 keV using a narrow beam transmission geometry. These coefficients were then used to obtain the values of mass attenuation coefficients, effective atomic number, effective electron density and mean free path. Good agreement has been observed between experimental and theoretical values of these parameters. From the obtained results it is reported here that from the barium-bismuth-borosilicate glasses are better shields to gamma-radiations in comparison to the standard radiation shielding concretes from the shielding point of view. The molar volume, FTIR and acoustic investigations have been used to study the structural properties of the prepared glass system. The obtained results reveal that the formation of non-bridging oxygens occurs at higher concentration of Bi2O3.

  10. On the nature of photoluminescence in Bismuth-doped silica glass.

    Science.gov (United States)

    Laguta, Oleksii V; Hamzaoui, Hicham El; Bouazaoui, Mohamed; Arion, Vladimir B; Razdobreev, Igor M

    2017-06-09

    We report on the investigation of Bismuth-doped pure silica glass without other co-dopant by the tech- nique of magnetic circular dichroism (MCD), which allows the direct probing of the ground state of optical centres. Taking into account the results of conventional optical spectroscopy, we show that the observed MCD bands belong to the centre responsible for the red photoluminescence in this material. Measurements of the temperature and field dependences indicate that the MCD effect is caused by the even-electron system. This, however, opposes the widespread opinion that Bi(2+) ions are the origin of red photoluminescence in Bismuth-doped silica glasses. On the other hand, the lasing centre responsi- ble for the near infrared photoluminescence does not exhibit any magnetic optical activity connected to its ground state. As a consequence, we conclude that the ground state of lasing centre is a magnetic singlet with the effective spin S = 0.

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

    Science.gov (United States)

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

    2017-01-01

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

  12. The Role of Bismuth in the Treatment of Gastroduodenal Pathology (Literature Review and Own Researches

    Directory of Open Access Journals (Sweden)

    Yu.M. Stepanov

    2016-10-01

    Full Text Available The article presents the history of colloidal bismuth subcitrate and considers the basic mechanisms of its effects on the gastric mucosa, both cytoprotective and anti-helicobacter. The recent data of the worldwide researches are given on the use of the bismuth subcitrate as a component of antibacterial therapy in order to improve the effectiveness of the eradication, especially under the resistance to the basic drugs. The results of own researches are also shown, they are dedicated to the dynamics of structural adjustment of the gastric mucosa in patients with chronic atrophic gastritis for 3 years after the eradication of H.pylori. The use of first-line therapy with the addition of the drug De-Nol allowed to achieve eradication in 94.3 % of patients and positive microstructural changes of the gastric mucosa.

  13. Effect of Fe2O3 on the physical and structural properties of bismuth silicate glasses

    Science.gov (United States)

    Parmar, Rajesh; Kundu, R. S.; Punia, R.; Aghamkar, P.; Kishore, N.

    2013-06-01

    Iron containing bismuth silicate glasses with compositions 70SiO2ṡ(100-x)Bi2O3ṡxFe2O3 have been prepared using conventional melt-quenching method and their amorphous nature has been investigated using XRD. Density has been measured using Archimedes' principle and molar volume (Vm) have also been estimated. With increase in Fe2O3 content, there is a decrease in density and molar volume of the glass samples. The glass transition temperature (Tg) have been determined using Differential Scanning Calorimetry (DSC) and are observed to increase with increase in Fe2O3 content. In the present glass system bismuth and iron plays the role of network modifier and the symmetry of silicate network goes on increasing with Fe2O3 content and it modifies the physical and structural properties of these glasses.

  14. Evaluation of bismuth shielding effectiveness in reducing breast absorbed dose during thoracic CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, T. C.; Mourao, A. P.; Santana, P. C.; Silva, T. A. [Federal University of Minas Gerais, Program of Nuclear Science and Techniques, Av. Pte. Antonio Carlos 6627, 31270-901 Belo Horizonte, Minas Gerais (Brazil)

    2015-10-15

    Computed Tomography (CT) is an essential method for tracking neoplasia and efficiently diagnosing a wide variety of thoracic diseases. CT is generally considered the most accurate choice for lung examination. Due to the growing use of CT, breast and other superficial and radiosensitive organs are unnecessarily irradiated during radiological procedures, thus requiring the development of strategies appropriate to optimize and, if possible, to reduce the radiation dose. The use of bismuth shielding to reduce radiation dose absorbed by breast during thoracic CT examinations has been the subject of many studies recently published by Brazilian and foreign authors of various fields. The purpose of this paper is both to accurately determine the glandular dose when breast is exposed to radiation and to assess the reduction in absorbed dose during thoracic CT examinations, using a set of Thermoluminescent Dosimeters, an anthropomorphic phantom and bismuth shielding. (Author)

  15. Bismuth Basic Nitrate as a Novel Adsorbent for Azo Dye Removal

    Directory of Open Access Journals (Sweden)

    E. A. Abdullah

    2012-01-01

    Full Text Available Bismuth basic nitrate (BBN and its TiO2-Ag modified sorbent, PTBA were successfully synthesized via a precipitation method. The structural characteristics of prepared sorbents were determined through different analytical techniques. The potential use of prepared sorbents for organic compounds' removal was evaluated using Methyl Orange and Sunset Yellow dyes as model pollutants in aqueous solutions. The experimental results showed that the presence of TiO2 and Ag particles during the crystal growth of bismuth basic nitrate has an effect on the crystal structure, point of zero charge (pHpzc, pore volume and diameter. The lower binding energy of Ti 2p core level peak indicates the octahedral coordination of TiO2 particles on the PTBA surface. The alteration of hydrophilic-hydrophobic characteristics of sorbent's surface improves the adsorptive performance of the modified sorbent and provides an efficient route for organic contaminants' removal from aqueous solutions.

  16. 67 cm long bismuth-based erbium doped fiber amplifier with wideband operation

    Science.gov (United States)

    Cheng, X. S.; Hamida, B. A.; Naji, A. W.; Ahmad, H.; Harun, S. W.

    2011-11-01

    In this paper, we demonstrate a wideband Bismuth-based erbium doped fiber amplifier (Bi-EDFA) using two pieces of bismuth-based erbium-doped fiber (Bi-EDF) with a total length of 67 cm as gain media in a double pass parallel configuration. Both Bi-EDFs have an erbium ion concentration of 6300 ppm. Compared to conventional silica-based erbium-doped fiber amplifier (Si-EDFA) with the same amount of erbium ions, the Bi-EDFA provides a higher attainable gain as well as a greater amplification bandwidth, which ranging from 1525 to 1620 nm. The proposed Bi-EDFA achieved a wideband gain of around 18 dB within the wavelength region from 1530 to 1565 nm. The noise figures are maintained below 10 dB within a wide wavelength region from 1535 nm to 1620 nm.

  17. A novel antifuse structure based on amorphous bismuth zinc niobate thin films

    Institute of Scientific and Technical Information of China (English)

    Wang Gang; Li Wei; Li Ping; Li Zuxiong; Fan Xue; Jiang Jing

    2012-01-01

    A novel antifuse structure with amorphous bismuth zinc niobate (a-BZN) dielectrics was proposed.The characteristics of the a-BZN antifuse were investigated.Programming direction of up to down was chosen to rupture the a-BZN antifuse.The breakdown voltage of the a-BZN antifuse was obtained at a magnitude of 6.56 V.A large off-state resistance of more than 1 GΩ for the a-BZN antifuse was demonstrated.The surface micrograph of the ruptured a-BZN antifuses was illustrated.Programming characteristics with the programming time of 0.46 ms and on-state properties with the average resistance value of 26.1 Ω of the a-BZN antifuse were exhibited.The difference of characteristics of the a-BZN antifuse from that of a cubic pyrochlore bismuth zinc niobate (cp-BZN) antifuse and gate oxide antifuse was compared and analyzed.

  18. Synthesis of Bismuth Ferrite Nanoparticles via a Wet Chemical Route at Low Temperature

    Directory of Open Access Journals (Sweden)

    Yongming Hu

    2011-01-01

    Full Text Available Nanoparticles (NPs of multiferroic bismuth ferrite (BiFeO3 with narrow size distributions were synthesized via a wet chemical route using bismuth nitrate and iron nitrate as starting materials and excess tartaric acid and citric acid as chelating agent, respectively, followed by thermal treatment. It was found that BiFeO3 NPs crystallized at ∼350∘C when using citric acid as chelating agent. Such crystallization temperature is much lower than that of conventional chemical process in which other types of chelating agent are used. BiFeO3 NPs with different sizes distributions show obvious ferromagnetic properties, and the magnetization is increased with reducing the particle size.

  19. Methylene blue photocatalysis in the presence of bismuth oxide under UV and solar light irradiation

    Directory of Open Access Journals (Sweden)

    Vanessa Rocha Liberatti

    2014-05-01

    Full Text Available Bismuth oxide (Bi2O3, an n-type semiconductor has been satisfactorily investigated for photocatalytic organic contaminant remediation. The Bi2O3 was prepared by solution combustion synthesis (SCS using as the oxidizing bismuth nitrate in acidic medium and urea as fuel. The influence of the type of synthesis on the photocatalytic properties of the oxide formed was investigated by XRD. From the diffractograms was verified that the materials obtained are predominantly of Bi2O3 crystals, it is possible to identify a sample with two crystalline phases, monoclinic (α-Bi2O3 and tetragonal (β-Bi2O3, and the other with only the monoclinic (α-Bi2O3. The two-phase oxide showed higher photocatalytic activity for discoloration of methylene blue under UV irradiation (60.59% and under sunlight (61.64% in 664 nm, followed kinetic law of pseudo-first order.

  20. Mixed-layered bismuth--oxygen--iodine materials for capture and waste disposal of radioactive iodine

    Energy Technology Data Exchange (ETDEWEB)

    Krumhansl, James L; Nenoff, Tina M

    2015-01-06

    Materials and methods of synthesizing mixed-layered bismuth oxy-iodine materials, which can be synthesized in the presence of aqueous radioactive iodine species found in caustic solutions (e.g. NaOH or KOH). This technology provides a one-step process for both iodine sequestration and storage from nuclear fuel cycles. It results in materials that will be durable for repository conditions much like those found in Waste Isolation Pilot Plant (WIPP) and estimated for Yucca Mountain (YMP). By controlled reactant concentrations, optimized compositions of these mixed-layered bismuth oxy-iodine inorganic materials are produced that have both a high iodine weight percentage and a low solubility in groundwater environments.

  1. Bismuth Infusion of ABS Enables Additive Manufacturing of Complex Radiological Phantoms and Shielding Equipment

    Directory of Open Access Journals (Sweden)

    Justin Ceh

    2017-02-01

    Full Text Available Radiopacity is a critical property of materials that are used for a range of radiological applications, including the development of phantom devices that emulate the radiodensity of native tissues and the production of protective equipment for personnel handling radioactive materials. Three-dimensional (3D printing is a fabrication platform that is well suited to creating complex anatomical replicas or custom labware to accomplish these radiological purposes. We created and tested multiple ABS (Acrylonitrile butadiene styrene filaments infused with varied concentrations of bismuth (1.2–2.7 g/cm3, a radiopaque metal that is compatible with plastic infusion, to address the poor gamma radiation attenuation of many mainstream 3D printing materials. X-ray computed tomography (CT experiments of these filaments indicated that a density of 1.2 g/cm3 of bismuth-infused ABS emulates bone radiopacity during X-ray CT imaging on preclinical and clinical scanners. ABS-bismuth filaments along with ABS were 3D printed to create an embedded human nasocranial anatomical phantom that mimicked radiological properties of native bone and soft tissue. Increasing the bismuth content in the filaments to 2.7 g/cm3 created a stable material that could attenuate 50% of 99mTechnetium gamma emission when printed with a 2.0 mm wall thickness. A shielded test tube rack was printed to attenuate source radiation as a protective measure for lab personnel. We demonstrated the utility of novel filaments to serve multiple radiological purposes, including the creation of anthropomorphic phantoms and safety labware, by tuning the level of radiation attenuation through material customization.

  2. Bismuth Infusion of ABS Enables Additive Manufacturing of Complex Radiological Phantoms and Shielding Equipment.

    Science.gov (United States)

    Ceh, Justin; Youd, Tom; Mastrovich, Zach; Peterson, Cody; Khan, Sarah; Sasser, Todd A; Sander, Ian M; Doney, Justin; Turner, Clark; Leevy, W Matthew

    2017-02-24

    Radiopacity is a critical property of materials that are used for a range of radiological applications, including the development of phantom devices that emulate the radiodensity of native tissues and the production of protective equipment for personnel handling radioactive materials. Three-dimensional (3D) printing is a fabrication platform that is well suited to creating complex anatomical replicas or custom labware to accomplish these radiological purposes. We created and tested multiple ABS (Acrylonitrile butadiene styrene) filaments infused with varied concentrations of bismuth (1.2-2.7 g/cm³), a radiopaque metal that is compatible with plastic infusion, to address the poor gamma radiation attenuation of many mainstream 3D printing materials. X-ray computed tomography (CT) experiments of these filaments indicated that a density of 1.2 g/cm³ of bismuth-infused ABS emulates bone radiopacity during X-ray CT imaging on preclinical and clinical scanners. ABS-bismuth filaments along with ABS were 3D printed to create an embedded human nasocranial anatomical phantom that mimicked radiological properties of native bone and soft tissue. Increasing the bismuth content in the filaments to 2.7 g/cm³ created a stable material that could attenuate 50% of (99m)Technetium gamma emission when printed with a 2.0 mm wall thickness. A shielded test tube rack was printed to attenuate source radiation as a protective measure for lab personnel. We demonstrated the utility of novel filaments to serve multiple radiological purposes, including the creation of anthropomorphic phantoms and safety labware, by tuning the level of radiation attenuation through material customization.

  3. Effect of bismuth addition to the triple therapy of Helicobacter pylori eradication

    Directory of Open Access Journals (Sweden)

    Ezel Taşdemir

    2012-03-01

    Full Text Available Objective: Success rates of amoxicillin, clarithromycin, and proton-pump inhibitor therapy in the Helicobacter pylori (Hp eradication have been decreasing. The aim of this study was to investigate the impact of bismuth subcitrate addition to triple therapy.Materials and methods: 148 patients diagnosed Hp infection with both histology and Hp stool antigen (HpSA tests were examined retrospectively. The patients were divided into 3 groups according to the eradication therapy. The first group received triple therapy with claritromycine 2x 500 mg, amoxicilline 2x1 g and PPI 2x1 for 14 days (n=40. The second group had bismuth subcitrate 4x120 mg with triple therapy for 14 days (n=73. The third group received 14 days pretreatment with bismuth subcitrate 4x1 together with PPI 2x1 then had triple therapy for 14 days (n=35. (14C urea breath and HpSA tests were used to detect posttreatment H.pylori status.Results: There were no statistical difference between the groups in terms of gender and age (p > 0.05. In group one 12 patients, in group two 20 patients and in group three 10 patients were identified as Hp positive after treatment. Eradication rates were 70% for group one, 72.6% for group two and 71.4% for group three respectively. There was no statistical difference between the groups in terms of eradication rates of treatment (p > 0.05.Conclusions: The addition of bismuth to conventional triple therapy did not affect treatment success rates.

  4. Electroless deposition of bismuth on Si(111) wafer from hydrogen fluoride solutions

    Energy Technology Data Exchange (ETDEWEB)

    Romann, T., E-mail: tavo.romann@ut.e [Institute of Chemistry, University of Tartu, 2 Jakobi Street, 51014 Tartu (Estonia); Anderson, E.; Kallip, S. [Institute of Chemistry, University of Tartu, 2 Jakobi Street, 51014 Tartu (Estonia); Maendar, H.; Matisen, L. [Institute of Physics, University of Tartu, 142 Riia Street, 51014 Tartu (Estonia); Lust, E. [Institute of Chemistry, University of Tartu, 2 Jakobi Street, 51014 Tartu (Estonia)

    2010-05-03

    Thin Bi layers were deposited by simple immersion of silicon chip into diluted HF aqueous solution, containing bismuth(III) ions. Bi nanoparticles or continuous up to 300 nm thick Bi film can be grown on silicon by the variation of the temperature and deposition time. Prepared surfaces have been characterized by atomic force microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, Raman scattering, photoluminescence and resistivity measurement methods. It was found that thinner Bi layers have a yellowish colour.

  5. Study of some health physics parameters of bismuth-ground granulated blast furnace slag shielding concretes

    Science.gov (United States)

    Kumar, Sandeep; Singh, Sukhpal

    2016-05-01

    The Bismuth-ground granulated blastfurnace slang (Bi-GGBFS) concrete samples were prepared. The weight percentage of different elements present inBi-GGBFS Shielding concretewas evaluated by Energy Dispersive X-ray Microanalysis (EDX). The exposure rate and absorbed dose rate characteristics were calculated theoretically for radioactive sources namely 241Am and 137Cs. Our calculations reveal that the Bi-GGBFS concretes are effective in shielding material for gamma radiations.

  6. Report - Melter Testing of New High Bismuth HLW Formulations VSL-13R2770-1

    Energy Technology Data Exchange (ETDEWEB)

    Kruger, Albert A.; Pegg, I. L.; Kot, W. K.; Gan, H.; Matlack, K. S.

    2013-11-13

    The primary objective of the work described was to test two glasses formulated for a high bismuth waste stream on the DM100 melter system. Testing was designed to determine processing characteristics and production rates, assess the tendency for foaming, and confirm glass properties. The glass compositions tested were previously developed to maintain high waste loadings and processing rates while suppressing the foaming observed in previous tests

  7. A kinetic study of jack-bean urease denaturation by a new dithiocarbamate bismuth compound

    Science.gov (United States)

    Menezes, D. C.; Borges, E.; Torres, M. F.; Braga, J. P.

    2012-10-01

    A kinetic study concerning enzymatic inhibitory effect of a new bismuth dithiocarbamate complex on jack-bean urease is reported. A neural network approach is used to solve the ill-posed inverse problem arising from numerical treatment of the subject. A reaction mechanism for the urease denaturation process is proposed and the rate constants, relaxation time constants, equilibrium constants, activation Gibbs free energies for each reaction step and Gibbs free energies for the transition species are determined.

  8. Influence of inherent strain on the curie temperature of rare earth ion-doped bismuth vanadate

    OpenAIRE

    Sooryanarayana, K; Row, TNG; R. Somashekar; Varma, KBR

    1998-01-01

    X-ray line broadening is found to be an effective parameter to estimate the strain associated with rare earth ion (Gd3+)-doped polycrystalline bismuth vanadate(Bi2VO5.5). The strain increases with increasing Gd3+ concentration. It is anisotropic and found to be maximum in (111) plane. The Curie temperature which is known to decrease with increase in the rare earth ion concentration in these compounds is correlated with increase in strain.

  9. Photoelectroactivity of Bismuth Vanadate Prepared by Combustion Synthesis: Effect of Different Fuels and Surfactants

    OpenAIRE

    Afonso,Renata; Serafim, Jessica A.; Lucilha,Adriana C.; Marcelo R. Silva; Lepre, Luiz F.; Ando, Romulo A.; Dall'Antonia,Luiz H.

    2014-01-01

    The bismuth vanadate (BiVO4) is a semiconductor that has attracted much attention due to the photocatalytic efficiency in the visible light region. The objective of this work was to synthesize monoclinic BiVO4 by solution combustion synthesis, with different surfactants and fuels and apply it as photoelectrodes. The characterization by infrared spectroscopy and Raman spectroscopy showed that all samples showed characteristic bands of the monoclinic structure BiVO4. The samples synthesized wit...

  10. Mechanistic insights into chemical and photochemical transformations of bismuth vanadate photoanodes

    OpenAIRE

    Toma, Francesca M.; Cooper, Jason K.; Kunzelmann, Viktoria; McDowell, Matthew T.; Yu, Jie; Larson, David M.; Borys, Nicholas J.; Abelyan, Christine; Beeman, Jeffrey W.; Yu, Kin Man; Yang, Jinhui; Chen, Le; Shaner, Matthew R.; Spurgeon, Joshua; Houle, Frances A.

    2016-01-01

    Artificial photosynthesis relies on the availability of semiconductors that are chemically stable and can efficiently capture solar energy. Although metal oxide semiconductors have been investigated for their promise to resist oxidative attack, materials in this class can suffer from chemical and photochemical instability. Here we present a methodology for evaluating corrosion mechanisms and apply it to bismuth vanadate, a state-of-the-art photoanode. Analysis of changing morphology and compo...

  11. Improving the photoactivity of bismuth vanadate thin film photoanodes through doping and surface modification strategies

    OpenAIRE

    Quiñonero, Javier; Lana Villarreal, Teresa; Gómez, Roberto

    2016-01-01

    Currently, one of the most attractive and desirable ways to solve the energy challenge is harvesting energy directly from the sunlight through the so-called artificial photosynthesis. Among the ternary oxides based on earth–abundant metals, bismuth vanadate has recently emerged as a promising photoanode. Herein, BiVO4 thin film photoanodes have been successfully synthesized by a modified metal-organic precursor decomposition method, followed by an annealing treatment. In an attempt to improve...

  12. Dielectric, piezoelectric, and pyroelectric anisotropy in KCL- modified grain-oriented bismuth vanadate ceramics

    OpenAIRE

    Shantha, K; Varma, KBR

    1999-01-01

    The effect of the additive KCl, on the structural, microstructural, and polar properties of bismuth vanadate (BiV) ceramics is investigated. The scanning electron microscopic (SEM) studies reveal a remarkable modification in the microstructure and the occurrence of high grain-orientation (75%) on KCl addition. The energy dispersive x ray (EDX) analyses indicate the presence of chemically inhomogeneous distribution of KCl, with core-shell-like grain structure. The KCl-modified BiV samples exhi...

  13. Analysis of the color alteration and radiopacity promoted by bismuth oxide in calcium silicate cement

    Directory of Open Access Journals (Sweden)

    Marina Angelica Marciano

    2013-07-01

    Full Text Available The aim of the study was to determine if the increase in radiopacity provided by bismuth oxide is related to the color alteration of calcium silicate-based cement. Calcium silicate cement (CSC was mixed with 0%, 15%, 20%, 30% and 50% of bismuth oxide (BO, determined by weight. Mineral trioxide aggregate (MTA was the control group. The radiopacity test was performed according to ISO 6876/2001. The color was evaluated using the CIE system. The assessments were performed after 24 hours, 7 and 30 days of setting time, using a spectrophotometer to obtain the ΔE, Δa, Δb and ΔL values. The statistical analyses were performed using the Kruskal-Wallis/Dunn and ANOVA/Tukey tests (p 3 mm equivalent of Al. The MTA group was statistically similar to the CSC / 30% BO group (p > 0.05. In regard to color, the increase of bismuth oxide resulted in a decrease in the ΔE value of the calcium silicate cement. The CSC group presented statistically higher ΔE values than the CSC / 50% BO group (p < 0.05. The comparison between 24 hours and 7 days showed higher ΔE for the MTA group, with statistical differences for the CSC / 15% BO and CSC / 50% BO groups (p < 0.05. After 30 days, CSC showed statistically higher ΔE values than CSC / 30% BO and CSC / 50% BO (p < 0.05. In conclusion, the increase in radiopacity provided by bismuth oxide has no relation to the color alteration of calcium silicate-based cements.

  14. Single crystals of bismuth silicon oxide grown by the Czochralski technique and their characterisation

    Directory of Open Access Journals (Sweden)

    ANDREJA VALCIC

    1999-09-01

    Full Text Available Single crystals of Bi12SiO20 were grown by the Czochralski technique. The critical diameter and the critical rate of rotation were calculated. Suitable polishing and etching solutions were determined. X-Ray measurements were performed on powdered samples to obtain the lattice parameters. The optical properties of the bismuth silicon oxide single crystals were investigated. The obtained results are discussed and compared with published data.

  15. Quantum Interference of Surface States in Bismuth Nanowires in Transverse Magnetic Fields

    Science.gov (United States)

    Konopko, L. A.; Huber, T. E.; Nikolaeva, A. A.; Burceacov, L. A.

    2013-06-01

    We report the results of studies of the magnetoresistance (MR) and electric field effect (EFE) of single-crystal Bi nanowires with diameter dMurakami, bismuth bilayers can exhibit the quantum spin Hall effect. A Bi crystal can be viewed as a stacking of bilayers with a honeycomblike lattice structure along the [111] direction. An interpretation of transverse MR oscillations with using this theory is presented.

  16. STUDY ON THE DETERMINATION OF TRACE BISMUTH(Ⅲ) BY THIN-LAYER RESIN PHASE SPECTROPHOTOMETRY

    Institute of Scientific and Technical Information of China (English)

    YAN Yongsheng; LU Xiaohua; FU Chengguang

    2003-01-01

    In this paper, a new thin-layer ion-exchange resin phase analytical method is introduced. It is based on that, the bismuthous cation can associate with iodic anions, so as to formed an anioncomplex [BiI-4] in a strong acidic environments. This anion complex can also exchanges with a weaker anions on the surface active site of anion exchange resin, so that a [R+] [BiI-4] solid phase binary associational system is produced. Owing to the solid system is a great many dispersive particulates, it can be pressed to a thin-layer by press tools of the so called "thin-layer resin phase"or "resin phase ", and using this solid association system spectrophotometry for the determination of trace metals. So it can increase the analytical sensitivity. This association system exhibits maximum absorbance at 460nm, and obeys Beer's law over the concentration range 0. 01ug/ml~1.20ug/ml of bismuthous(Ⅲ). It has a molar absorptivity of 7.1 ×105 [L/mol cm]. It indicated the resin phase spectrophotometry is a sensitive analytical method for trace bismuthous. It is 18 times higher than routine aqueous spectrophotometry. The relative standard deviations is 1.82% (n=6) for the measurements of 0. 5ug/ml Bi(Ⅲ). The detection limit of Bismuthous(Ⅲ) is 1.4 ×10-8mol/L. The method has applied to the analysis Bi(Ⅲ) in environmental water samples.

  17. Bismuth Infusion of ABS Enables Additive Manufacturing of Complex Radiological Phantoms and Shielding Equipment

    Science.gov (United States)

    Ceh, Justin; Youd, Tom; Mastrovich, Zach; Peterson, Cody; Khan, Sarah; Sasser, Todd A.; Sander, Ian M.; Doney, Justin; Turner, Clark; Leevy, W. Matthew

    2017-01-01

    Radiopacity is a critical property of materials that are used for a range of radiological applications, including the development of phantom devices that emulate the radiodensity of native tissues and the production of protective equipment for personnel handling radioactive materials. Three-dimensional (3D) printing is a fabrication platform that is well suited to creating complex anatomical replicas or custom labware to accomplish these radiological purposes. We created and tested multiple ABS (Acrylonitrile butadiene styrene) filaments infused with varied concentrations of bismuth (1.2–2.7 g/cm3), a radiopaque metal that is compatible with plastic infusion, to address the poor gamma radiation attenuation of many mainstream 3D printing materials. X-ray computed tomography (CT) experiments of these filaments indicated that a density of 1.2 g/cm3 of bismuth-infused ABS emulates bone radiopacity during X-ray CT imaging on preclinical and clinical scanners. ABS-bismuth filaments along with ABS were 3D printed to create an embedded human nasocranial anatomical phantom that mimicked radiological properties of native bone and soft tissue. Increasing the bismuth content in the filaments to 2.7 g/cm3 created a stable material that could attenuate 50% of 99mTechnetium gamma emission when printed with a 2.0 mm wall thickness. A shielded test tube rack was printed to attenuate source radiation as a protective measure for lab personnel. We demonstrated the utility of novel filaments to serve multiple radiological purposes, including the creation of anthropomorphic phantoms and safety labware, by tuning the level of radiation attenuation through material customization. PMID:28245589

  18. Ultrasonic and Thermal Properties of Borate and Phosphate Glasses Containing Bismuth and Lead

    Science.gov (United States)

    Aziz, Sidek Hj. Abd.; Ahmad, Hamezan; Wahab, Zaidan A.; Sulaiman, Zainal Abidin; Talib, Zainal Abidin; Shaari, A. Halim; Senin, H. B.

    2007-05-01

    Systematic series of (B2O3,P2O5)-Bi2O3-PbO glasses have been successfully prepared by using the rapid quenching technique in which each oxide content changes for every series on the basis of its weight percentage. Their amorphous natures were confirmed earlier by the x-ray diffraction technique. The experimental results show that the density of both glasses, determined by using the Archimedes principle, increases with the glass modifier content. This is due to the replacement of Bi2O3 and PbO in the borate and phosphate glassy networks. The molar volume for borate glass increases with the addition of bismuth and lead oxides, but a reverse trend occurs for the phosphate glass. The longitudinal and shear ultrasound velocities, determined by the MBS 8000 system, of both lead bismuth borate and phosphate glasses show a decreasing trend as more PbO and Bi2O3 are added to the glass system. The increase in PbO/Bi2O3 content was probably related to the progressive increase in the concentration of non-bridging oxygen (NBOs). Thermal studies of the glass, using the Labsys DTA-Setaram machine, show that the value of the glass transition temperature (Tg) is closely related to the chemical bond in the system. In lead bismuth borate glasses, the addition of more Pb2+ and Bi3+ results in a more dominant ionic bond character in the system and hence decreases Tg of the sample. However, in lead bismuth phosphate glasses, the addition of Pb2+ and Bi3+ not only failed to weaken the covalent character in P-O-P bonds, but strengthened it further, leading to an increment in the values of Tg.

  19. Compositional dependence of optical band gap and refractive index in lead and bismuth borate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Mallur, Saisudha B.; Czarnecki, Tyler; Adhikari, Ashish; Babu, Panakkattu K.

    2015-08-15

    Highlights: • Refractive indices increase with increasing PbO/Bi{sub 2}O{sub 3} content. • Optical band gap arises due to direct forbidden transition. • Optical band gaps decrease with increasing PbO/Bi{sub 2}O{sub 3} content. • New empirical relation between the optical band gap and the refractive index. - Abstract: We prepared a series of lead and bismuth borate glasses by varying PbO/Bi{sub 2}O{sub 3} content and studied refractive index and optical band gap as a function of glass composition. Refractive indices were measured very accurately using a Brewster’s angle set up while the optical band gaps were determined by analyzing the optical absorption edge using the Mott–Davis model. Using the Lorentz–Lorentz method and the effective medium theory, we calculated the refractive indices and then compared them with the measured values. Bismuth borate glasses show better agreement between the calculated values of the refractive index and experimental values. We used a differential method based on Mott–Davis model to obtain the type of transition and optical band gap (E{sub opt}) which in turn was compared with the value of E{sub opt} obtained using the extinction coefficient. Our analysis shows that in both lead and bismuth borate glasses, the optical band gap arises due to direct forbidden transition. With increasing PbO/Bi{sub 2}O{sub 3} content, the absorption edge shifts toward longer wavelengths and the optical band gap decreases. This behavior can be explained in terms of changes to the Pb−O/Bi−O chemical bonds with glass composition. We obtained a new empirical relation between the optical band gap and the refractive index which can be used to accurately determine the electronic oxide polarizability in lead and bismuth oxide glasses.

  20. Facile production of thermoelectric bismuth telluride thick films in the presence of polyvinyl alcohol.

    Science.gov (United States)

    Lei, C; Burton, M R; Nandhakumar, I S

    2016-06-01

    Bismuth telluride is currently the best performing thermoelectric material for room temperature operations in commercial thermoelectric devices. We report the reproducible and facile production of 600 micron thick bismuth telluride (Bi2Te3) layers by low cost and room temperature pulsed and potentiostatic electrodeposition from a solution containing bismuth and tellurium dioxide in 2 M nitric acid onto nickel in the presence of polyvinyl alcohol (PVA). This was added to the electrolyte to promote thick layer formation and its effect on the structure, morphology and composition of the electrodeposits was investigated by SEM and EDX. Well adherent, uniform, compact and stoichiometric n-type Bi2Te3 films with a high Seebeck coefficient of up to -200 μV K(-1) and a high electrical conductivity of up to 400 S cm(-1) resulting in a power factor of 1.6 × 10(-3) W m(-1) K(-2) at film growth rates of 100 μm h(-1) for potentiostatic electrodeposition were obtained. The films also exhibited a well defined hexagonal structure as determined by XRD.

  1. Opto-electronic properties of bismuth oxide films presenting different crystallographic phases

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, Celia L. [Instituto de Investigaciones en Materiales, UNAM, Circuito Exterior s/n CU, México D.F. 04510 (Mexico); Posgrado en Ciencia e Ingeniería de Materiales, UNAM, Unidad de Posgrado, Edificio C, Piso 1, Zona Cultural de CU, México, D.F. 04510 (Mexico); Depablos-Rivera, Osmary, E-mail: osmarydep@yahoo.com [Instituto de Investigaciones en Materiales, UNAM, Circuito Exterior s/n CU, México D.F. 04510 (Mexico); Posgrado en Ciencia e Ingeniería de Materiales, UNAM, Unidad de Posgrado, Edificio C, Piso 1, Zona Cultural de CU, México, D.F. 04510 (Mexico); Silva-Bermudez, Phaedra [Instituto de Investigaciones en Materiales, UNAM, Circuito Exterior s/n CU, México D.F. 04510 (Mexico); Instituto Nacional de Rehabilitación, Calz. México Xochimilco No. 289 Col. Arenal de Guadalupe, C.P.14389, Ciudad de México, D.F. (Mexico); Muhl, Stephen [Instituto de Investigaciones en Materiales, UNAM, Circuito Exterior s/n CU, México D.F. 04510 (Mexico); Zeinert, Andreas; Lejeune, Michael; Charvet, Stephane; Barroy, Pierre [Laboratoire de Physique de la Matière Condensée, Université de Picardie Jules Verne, 33 rue Saint Leu, 80039 Amiens Cedex 1 (France); Camps, Enrique [Instituto Nacional de Investigaciones Nucleares, Carretera México-Toluca S/N, kilómetro 36.5. La Marquesa, Municipio de Ocoyoacac, CP 52750, Estado de México (Mexico); Rodil, Sandra E. [Instituto de Investigaciones en Materiales, UNAM, Circuito Exterior s/n CU, México D.F. 04510 (Mexico)

    2015-03-02

    The optical, electrical and structural properties of bismuth oxide thin films deposited by radio frequency reactive magnetron sputtering were studied. The Bi{sub 2}O{sub 3} thin films were grown on Si and glass substrates under different power and substrate temperatures in an oxygen-enriched plasma leading to films with different crystalline phase as evidenced by X-ray diffraction and Raman spectroscopy. The optical properties of the films were measured using ellipsometric spectroscopy and optical transmission spectra. In order to parameterize the optical dispersion functions (n, k) of the films, the Tauc–Lorentz dispersion model was used. The optical bandgap was then assessed by different methods and the results are compared to the thermal variations of the electrical resistivity of the films. It was found that the refractive index, extinction coefficient and optical gap strongly depend on the deposition conditions and the crystalline phase; the fluorite defect cubic δ-Bi{sub 2}O{sub 3} phase showed the lowest optical gap and lower resistivity. - Highlights: • Different bismuth oxide phases were obtained by sputtering. • The power and substrate temperature were the two key parameters. • Room temperature delta-Bi{sub 2}O{sub 3} thin films were obtained. • The optical bandgap was around 1.5 and 2.2 eV, depending on the phase. • The bismuth oxide films presented activation energies around 1 eV.

  2. Landau spectrum and twin boundaries of bismuth in the extreme quantum limit.

    Science.gov (United States)

    Zhu, Zengwei; Fauqué, Benoît; Malone, Liam; Antunes, Arlei Borba; Fuseya, Yuki; Behnia, Kamran

    2012-09-11

    The Landau spectrum of bismuth is complex and includes many angle-dependent lines in the extreme quantum limit. The adequacy of single-particle theory to describe this spectrum in detail has been an open issue. Here, we present a study of angle-resolved Nernst effect in bismuth, which maps the angle-resolved Landau spectrum for the entire solid angle up to 28 T. The experimental map is in good agreement with the results of a theoretical model with parabolic dispersion for holes and an extended Dirac Hamiltonian for electrons. The angular dependence of additional lines in the Landau spectrum allows us to uncover the mystery of their origin. They correspond to the lines expected for the hole Landau levels in a secondary crystal tilted by 108°, the angle between twinned crystals in bismuth. According to our results, the electron reservoirs of the two identical tilted crystals have different chemical potentials, and carriers across the twin boundary have different concentrations. An exceptional feature of this junction is that it separates two electron-hole compensated reservoirs. The link between this edge singularity and the states wrapping a three-dimensional electron gas in the quantum limit emerges as an outstanding open question.

  3. LiBi3S5-A lithium bismuth sulfide with strong cation disorder

    Science.gov (United States)

    Nakhal, Suliman; Wiedemann, Dennis; Stanje, Bernhard; Dolotko, Oleksandr; Wilkening, Martin; Lerch, Martin

    2016-06-01

    Among chalcogenide semiconductors for thermoelectric applications, alkali-metal bismuth compounds occur in many complex compositions favorable for high performance. Although LiBi3S5 had been announced in 1977, the potential 1D lithium-ion conductor has hitherto eluded selective synthesis and structure determination. In this study, we present a solid-state route to phase-pure LiBi3S5 powder starting from LiBiS2 and Bi2S3. Neutron diffractograms and lithium NMR spectra reveal its crystal structure to be a cation-disordered variety of the AgBi3S5 type (synthetic pavonite; monoclinic, C2/m). Topological analyses and lithium NMR relaxometry suggest that correlated lithium-ion diffusion with activation energies up to 0.66(2) eV occurs along the channels in b direction including tetrahedral voids. Because of cation disorder, immobile bismuth(III) ions clog these pathways, making LiBi3S5 a moderate to poor ionic conductor. The synthesis route reported is nonetheless promising for new lithium bismuth sulfides with, possibly ordered, structure types of the pavonite homologous series.

  4. Use of a Soluble Anode in Electrodeposition of Thick Bismuth Telluride Layers

    Science.gov (United States)

    Maas, M.; Diliberto, S.; de Vaulx, C.; Azzouz, K.; Boulanger, C.

    2014-10-01

    Integration of thermoelectric devices within an automotive heat exchanger could enable conversion of lost heat into electrical energy, contributing to improved total output from the engine. For this purpose, synthesis of thick bismuth telluride (Bi2Te3) films is required. Bismuth telluride has been produced by an electrochemical method in nitric acid with a sacrificial bismuth telluride anode as the source of cations. The binary layer grows on the working electrode while the counter-electrode, a Bi2Te3 disk obtained by high frequency melting, is oxidized to BiIII and TeIV. This process leads to auto-regeneration of the solution without modification of its composition. The thickness of films deposited by use of the Bi2Te3 anode was approximately 10 times that without. To demonstrate the utility of a soluble anode in electrochemical deposition, we report characterization of the composition and morphology of the films obtained under different experimental conditions. Perfectly dense and regular Bi2Te3 films (˜400 μm) with low internal stress and uniform composition across the cross-section were prepared. Their thermoelectric properties were assessed.

  5. Electrical conductivity and crystallization of amorphous bismuth ruthenate thin films deposited by spray pyrolysis.

    Science.gov (United States)

    Ryll, Thomas; Brunner, Andreas; Ellenbroek, Stefan; Bieberle-Hutter, Anja; Rupp, Jennifer L M; Gauckler, Ludwig J

    2010-11-14

    Amorphous oxide thin films with tailored functionality will be crucial for the next generation of micro-electro-mechanical-systems (MEMS). Due to potentially favorable electronic and catalytic properties, amorphous bismuth ruthenate thin films might be applied in this regard. We report on the deposition of amorphous bismuth ruthenate thin films by spray pyrolysis, their crystallization behavior and electrical conductivity. At room temperature the 200 nm thin amorphous films exhibit a high electrical conductivity of 7.7 × 10(4) S m(-1), which was found to be slightly thermally activated (E(a) = 4.1 × 10(-3) eV). It follows that a long-range order of the RuO(6) octahedra is no precondition for the electrical conductivity of Bi(3)Ru(3)O(11). Upon heating to the temperature range between 490 °C and 580 °C the initially amorphous films crystallize rapidly. Simultaneously, a transition from a dense and continuous film to isolated Bi(3)Ru(3)O(11) particles on the substrate takes place. Solid-state agglomeration is proposed as the mechanism responsible for disintegration. The area specific resistance of Bi(3)Ru(3)O(11) particles contacted by Pt paste on gadolinia doped ceria electrolyte pellets was found to be 7 Ω cm(2) at 607 °C in air. Amorphous bismuth ruthenate thin films are proposed for application in electrochemical devices operating at low temperatures, where a high electrical conductivity is required.

  6. Effect of bismuth ion substitution on structural properties of zinc ferrite nanoparticles

    Directory of Open Access Journals (Sweden)

    Naraavula Suresh Kumar

    2016-06-01

    Full Text Available Bismuth doped nano zinc ferrite particles having the general formula ZnFe2-xBixO4 (x = 0.00, 0.05, 0.10, 0.15, 0.20 and 0.25 were synthesized by sol-gel combustion method. The effect of bismuth doping on structural properties were investigated. The X-ray diffraction (XRD spectra confirm the single phase cubic spinel structure. The average crystallite sizes of all the samples were determined by Debye-Scherrer equation and are in the range 16–20 nm. The lattice parameter increases with the increase of bismuth ion concentration. This is due to the larger ionic radius of Bi3+ ions substituting smaller Fe3+ ions at octahedral sites (B-sites. The surface morphology of all compounds was studied by scanning electron microscope (SEM. The microstructure analysis and the particle size were examined by transmission electron microscope (TEM. The compositional stoichiometry of these samples was verified by energy dispersive spectroscopy (EDS analysis.

  7. Bismuth Modified Porous Silica Preparation, Characterization and Photocatalytic Activity Evaluation for Degradation of Isoproturon

    Institute of Scientific and Technical Information of China (English)

    Anil Kumar Reddy Police; Srinivas Basavaraju; Durga Kumari Valluri; Subrahmanyam Machiraju

    2013-01-01

    Porous silica prepared by using an acrylic emulsion has been impregnated with bismuth ion resulting in Bi2Sio5 species containing surface.The as-prepared materials have been characterized by X-ray diffraction spectroscopy (XRD),X-ray photoelectron spectroscopy (XPS),UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS),scanning electron microscopy (SEM),energy dispersive analysis of X-ray (EDAX),transmission electron microscopy (TEM),Fourier transform infrared spectroscopy (FTIR) and N2 adsorption/desorption techniques.EDAX analysis confirms the penetration of bismuth ions into the framework of silica to form Bi2Sio5,which is substantiated by XRD.The UV-Vis DRS shows that the catalysts are optically active and XPS confirms the inclusion of bismuth into the framework of silica.FTIR spectra illustrate the formation of Bi-O-Si linkages in the porous silica framework.SEM and TEM show the spherical morphology,whereas N2 adsorption/desorption study confirms the porosity of the prepared materials.The photocatalytic activity of the material is evaluated for the degradation of isoproturon herbicide and it is found that the material is active as compared to the commercial P-25 Degussa Tio2.

  8. Synthesis, crystal growth and mechanical properties of Bismuth Silicon Oxide (BSO) single crystal

    Energy Technology Data Exchange (ETDEWEB)

    Riscob, B. [CSIR – National Physical Laboratory, Crystal Growth and X-ray Analysis, New Delhi 110 012 (India); Institute for Plasma Research, Bhat, Gandhinagar 382428, Gujarat (India); Shkir, Mohd. [CSIR – National Physical Laboratory, Crystal Growth and X-ray Analysis, New Delhi 110 012 (India); Ganesh, V. [Department of Physics, Kakatiya University, Warangal 506 009 (India); Vijayan, N.; Maurya, K.K. [CSIR – National Physical Laboratory, Crystal Growth and X-ray Analysis, New Delhi 110 012 (India); Kishan Rao, K. [Department of Physics, Kakatiya University, Warangal 506 009 (India); Bhagavannarayana, G., E-mail: bhagavan@mail.nplindia.ernet.in [CSIR – National Physical Laboratory, Crystal Growth and X-ray Analysis, New Delhi 110 012 (India)

    2014-03-05

    Highlights: • Synthesis of Bismuth Silicon Oxide (BSO). • Single crystal growth of BSO by Czochralski (Cz) method. • Complete mechanical analysis by device fabrication point of view. • Theoretical and experimental calculations of mechanical properties. -- Abstract: Bismuth Silicon Oxide (BSO) is an efficient material for piezo-electric and electro-optic applications. In this article, growth of BSO single crystal by high temperature Czochralski melt growth technique and its detailed mechanical characterization by Vickers microhardness, fracture toughness, crack propagation, brittleness index and yield strength have been reported. The raw material was synthesized by solid state reaction using the stoichiometric ratio of high purity bismuth tri-oxide and silicon di-oxide. The synthesized material was charged in the platinum crucible and then melted. The required rotation and pulling rate was optimized for BSO single crystal growth and good quality single crystal has been harvested after a time span of 5 days. Powder X-ray diffraction analysis confirms the parent crystallization phase of BSO. The experimentally studied mechanical behavior of the crystal is explained using various theoretical models. The anisotropic nature of the crystals is studied using Knoop indentation technique.

  9. Dirac fermions at high-index surfaces of bismuth chalcogenide topological insulator nanostructures

    Science.gov (United States)

    Virk, Naunidh; Yazyev, Oleg V.

    2016-01-01

    Binary bismuth chalcogenides Bi2Se3, Bi2Te3, and related materials are currently being extensively investigated as the reference topological insulators (TIs) due to their simple surface-state band dispersion (single Dirac cone) and relatively large bulk band gaps. Nanostructures of TIs are of particular interest as an increased surface-to-volume ratio enhances the contribution of surfaces states, meaning they are promising candidates for potential device applications. So far, the vast majority of research efforts have focused on the low-energy (0001) surfaces, which correspond to natural cleavage planes in these layered materials. However, the surfaces of low-dimensional nanostructures (nanoplatelets, nanowires, nanoribbons) inevitably involve higher-index facets. We perform a systematic ab initio investigation of the surfaces of bismuth chalcogenide TI nanostructures characterized by different crystallographic orientations, atomic structures and stoichiometric compositions. We find several stable terminations of high-index surfaces, which can be realized at different values of the chemical potential of one of the constituent elements. For the uniquely defined stoichiometric termination, the topological Dirac fermion states are shown to be strongly anisotropic with a clear dependence of Fermi velocities and spin polarization on the surface orientation. Self-doping effects and the presence of topologically trivial mid-gap states are found to characterize the non-stoichiometric surfaces. The results of our study pave the way towards experimental control of topologically protected surface states in bismuth chalcogenide nanostructures. PMID:26847409

  10. Efficient photoelectrochemical hydrogen production from bismuth vanadate-decorated tungsten trioxide helix nanostructures

    Science.gov (United States)

    Shi, Xinjian; Choi, Il Yong; Zhang, Kan; Kwon, Jeong; Kim, Dong Yeong; Lee, Ja Kyung; Oh, Sang Ho; Kim, Jong Kyu; Park, Jong Hyeok

    2014-09-01

    Tungsten trioxide/bismuth vanadate heterojunction is one of the best pairs for solar water splitting, but its photocurrent densities are insufficient. Here we investigate the advantages of using helical nanostructures in photoelectrochemical solar water splitting. A helical tungsten trioxide array is fabricated on a fluorine-doped tin oxide substrate, followed by subsequent coating with bismuth vanadate/catalyst. A maximum photocurrent density of ~5.35±0.15 mA cm-2 is achieved at 1.23 V versus the reversible hydrogen electrode, and related hydrogen and oxygen evolution is also observed from this heterojunction. Theoretical simulations and analyses are performed to verify the advantages of this helical structure. The combination of effective light scattering, improved charge separation and transportation, and an enlarged contact surface area with electrolytes due to the use of the bismuth vanadate-decorated tungsten trioxide helical nanostructures leads to the highest reported photocurrent density to date at 1.23 V versus the reversible hydrogen electrode, to the best of our knowledge.

  11. Simultaneous enhancements in photon absorption and charge transport of bismuth vanadate photoanodes for solar water splitting

    Science.gov (United States)

    Kim, Tae Woo; Ping, Yuan; Galli, Giulia A.; Choi, Kyoung-Shin

    2015-10-01

    n-Type bismuth vanadate has been identified as one of the most promising photoanodes for use in a water-splitting photoelectrochemical cell. The major limitation of BiVO4 is its relatively wide bandgap (~2.5 eV), which fundamentally limits its solar-to-hydrogen conversion efficiency. Here we show that annealing nanoporous bismuth vanadate electrodes at 350 °C under nitrogen flow can result in nitrogen doping and generation of oxygen vacancies. This gentle nitrogen treatment not only effectively reduces the bandgap by ~0.2 eV but also increases the majority carrier density and mobility, enhancing electron-hole separation. The effect of nitrogen incorporation and oxygen vacancies on the electronic band structure and charge transport of bismuth vanadate are systematically elucidated by ab initio calculations. Owing to simultaneous enhancements in photon absorption and charge transport, the applied bias photon-to-current efficiency of nitrogen-treated BiVO4 for solar water splitting exceeds 2%, a record for a single oxide photon absorber, to the best of our knowledge.

  12. The synthesis of bismuth vanadate powders and their photocatalytic properties under visible light irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Shen Yue [Institute of Material Physical Chemistry, Huaqiao University, Key Laboratory for Functional Materials of Fujian Higher Education, Quanzhou, Fujian 362021 (China); Huang Miaoliang, E-mail: huangml@hqu.edu.c [Institute of Material Physical Chemistry, Huaqiao University, Key Laboratory for Functional Materials of Fujian Higher Education, Quanzhou, Fujian 362021 (China); Huang Yi; Lin Jianming; Wu Jihuai [Institute of Material Physical Chemistry, Huaqiao University, Key Laboratory for Functional Materials of Fujian Higher Education, Quanzhou, Fujian 362021 (China)

    2010-04-30

    Bismuth vanadate powders were prepared by hydrothermal method with NaVO{sub 3} and Bi(NO{sub 3}){sub 3} as starting materials and with Na{sub 2}CO{sub 3} to adjust pH, and characterized by XRD, SEM, EDS and surface area analyzer. The results showed that the phase formation of bismuth vanadate depended on the adding amount of Na{sub 2}CO{sub 3}. The bismuth vanadate samples existed as monoclinic BiVO{sub 4} by adding 0.019 and 0.038 mol of Na{sub 2}CO{sub 3} with corresponding pH value of 0.2 and 5.8, respectively, and as Bi{sub 4}V{sub 2}O{sub 11} by adding 0.057 mol of Na{sub 2}CO{sub 3} with corresponding pH value of 9.7. The photocatalytic activities of the samples were evaluated by the decolorization of methylene blue (MB) under visible light irradiation. The sample with monoclinic form obtained by adding 0.019 mol of Na{sub 2}CO{sub 3} had the highest photocatalytic activity, the decolorization rate of MB reached to 96.4% under visible light irradiation in 200 min and the reaction rate constant was 0.015 min{sup -1}.

  13. Stability of topological properties of bismuth (1 1 1) bilayer

    Science.gov (United States)

    Bieniek, Maciej; Woźniak, Tomasz; Potasz, Paweł

    2017-04-01

    We investigate the electronic and transport properties of the bismuth (1 1 1) bilayer in the context of the stability of its topological properties against different perturbations. The effects of spin-orbit coupling variations, geometry relaxation and interaction with a substrate are considered. The transport properties are studied in the presence of Anderson disorder. Band structure calculations are performed within the multi-orbital tight-binding model and density functional theory methods. A band inversion process in the bismuth (1 1 1) infinite bilayer and an evolution of the edge state dispersion in ribbons as a function of spin-orbit coupling strength are analyzed. A significant change in the orbital composition of the conduction and valence bands is observed during a topological phase transition. The topological edge states are shown to be weakly affected by the effect of ribbon geometry relaxation. The interaction with a substrate is considered for narrow ribbons on top of another bismuth (1 1 1) bilayer. This corresponds to a weakly interacting case and the effect is similar to an external perpendicular electric field. Robust quantized conductance is observed when the Fermi energy lies within the energy gap, where only two counter-propagating edge states are present. For energies where the Fermi level crosses more in-gap states, scattering is possible between the channels lying close in the k-space. When the energy of the edge states overlaps the valence states, no topological protection is observed.

  14. Efficient gas sensitivity in mixed bismuth ferrite micro (cubes) and nano (plates) structures

    Energy Technology Data Exchange (ETDEWEB)

    Waghmare, Shivaji D.; Jadhav, Vijaykumar V.; Gore, Shaym K. [Center for Nanomaterials and Energy Devices, School of Physical Sciences, Swami Ramanand Teerth Marathwada University, Nanded 431606, Maharashtra (India); Yoon, Seog-Joon; Ambade, Swapnil B. [Inorganic Nanomaterials Laboratory, Department of Chemistry, Hanyang University, Seoul 133-1791 (Korea, Republic of); Lokhande, B.J. [Department of Physics, Solapur University, Solapur (India); Mane, Rajaram S., E-mail: rsmane_2000@yahoo.com [Center for Nanomaterials and Energy Devices, School of Physical Sciences, Swami Ramanand Teerth Marathwada University, Nanded 431606, Maharashtra (India); Han, Sung-Hwan, E-mail: shhan@hanyang.ac.kr [Inorganic Nanomaterials Laboratory, Department of Chemistry, Hanyang University, Seoul 133-1791 (Korea, Republic of)

    2012-12-15

    Graphical abstract: Display Omitted Highlights: ► Micro (cubes) structure embedded in nano (plates) of bismuth ferrite was prepared by a chemical method. ► These structures were characterized by XRD and SEM. ► LPG, CO{sub 2} and NH{sub 4} gases were exposed. ► Properties related to gas sensors were measured and reported. -- Abstract: Mixed micro (cubes) and nano (plates) structures of bismuth ferrite (BFO) have been synthesized by a simple and cost-effective wet-chemical method. Structural, morphological and phase confirmation characteristics are measured using X-ray diffraction, field-emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray analysis techniques. The digital FE-SEM photo-images of BFO sample confirmed an incubation of discrete micro-cubes into thin and regularly placed large number of nano-plates. The bismuth ferrite, with mixed structures, films show considerable performance when used in liquefied petroleum (LPG), carbon dioxide (CO{sub 2}) and ammonium (NH{sub 3}) gas sensors application. Different chemical entities in LPG have made it more efficient with higher sensitivity, recovery and response times compared to CO{sub 2} and NH{sub 3} gases. Furthermore, effect of palladium surface treatment on the gas sensitivity and the charge transfer resistances of BFO mixed structures is investigated and reported.

  15. Dirac fermions at high-index surfaces of bismuth chalcogenide topological insulator nanostructures

    Science.gov (United States)

    Virk, Naunidh; Yazyev, Oleg V.

    2016-02-01

    Binary bismuth chalcogenides Bi2Se3, Bi2Te3, and related materials are currently being extensively investigated as the reference topological insulators (TIs) due to their simple surface-state band dispersion (single Dirac cone) and relatively large bulk band gaps. Nanostructures of TIs are of particular interest as an increased surface-to-volume ratio enhances the contribution of surfaces states, meaning they are promising candidates for potential device applications. So far, the vast majority of research efforts have focused on the low-energy (0001) surfaces, which correspond to natural cleavage planes in these layered materials. However, the surfaces of low-dimensional nanostructures (nanoplatelets, nanowires, nanoribbons) inevitably involve higher-index facets. We perform a systematic ab initio investigation of the surfaces of bismuth chalcogenide TI nanostructures characterized by different crystallographic orientations, atomic structures and stoichiometric compositions. We find several stable terminations of high-index surfaces, which can be realized at different values of the chemical potential of one of the constituent elements. For the uniquely defined stoichiometric termination, the topological Dirac fermion states are shown to be strongly anisotropic with a clear dependence of Fermi velocities and spin polarization on the surface orientation. Self-doping effects and the presence of topologically trivial mid-gap states are found to characterize the non-stoichiometric surfaces. The results of our study pave the way towards experimental control of topologically protected surface states in bismuth chalcogenide nanostructures.

  16. Underpotential Deposition Study and Determination of Bismuth on Gold Electrode by Using Voltammetry

    Institute of Scientific and Technical Information of China (English)

    DU,Yong-Ling(杜永令); WANG,Chun-Ming(王春明)

    2002-01-01

    The cyclic voltammetry (CV) and the semidifferential anodic stripping voltanmetry (SdASV) were used for investigation of bismuth(Ⅲ) underpotential deposition (UPD) on gold electrode. Based on the excellent electrochemical properties of Au/Bi UPD system, a new method for determining bismuth (Ⅲ)was established. A solution of 0.1 mol/L HNO3 was selected as the supporting electrolyte. Factors affecting the Bi(Ⅲ) UPD and stripping steps were investigated and an opthmized analytical procedure was developed. The calibration plots for Bi(Ⅲ) concentration in the range 1.25 × 10-8-1.0 × 10-7 mol/L were obtained. The detection limit, calculated as three times the standard deviation of the analytical signal of 8.3×10-8 mol/L for a 90 s electrodeposition at 0.00 V (while the solution magnetically stirred at a speed of 300 rpm), was 7.5× 10-9 mol/ L. For8 successive determinations of 1.25 × 10-7 mol/L Bi(Ⅲ), the obtained RSD (relative standard deviation) was 0.4%. The developed method was applied to bismuth determining in medicine and urine samples. The analytical results were compared with that of atomic emission spectrometry (AES) method.

  17. Glass composite waste forms for iodine confined in bismuth-embedded SBA-15

    Science.gov (United States)

    Yang, Jae Hwan; Park, Hwan Seo; Ahn, Do-Hee; Yim, Man-Sung

    2016-11-01

    The aim of this study was to stabilize bismuth-embedded SBA-15 that captured iodine gas by fabrication of monolithic waste forms. The iodine containing waste was mixed with Bi2O3 (a stabilizing additive) and low-temperature sintering glass followed by pelletizing and the sintering process to produce glass composite materials. Iodine volatility during the sintering process was significantly affected by the ratio of Bi2O3 and the glass composition. It was confirmed that BiI3, the main iodine phase within bismuth-embedded SBA-15, was effectively transformed to the mixed phases of Bi5O7I and BiOI. The initial leaching rates of iodine from the glass composite waste forms ranged 10-3-10-2 g/m2 day, showing the stability of the iodine phases encapsulated by the glassy networks. It was also observed that common groundwater anions (e.g., chloride, carbonate, sulfite, and fluoride) elevated the iodine leaching rate by anion exchange reactions. The present results suggest that the glass composite waste form of bismuth-embedded SBA-15 could be a candidate material for stable storage of 129I.

  18. Alkali-metal-supported bismuth polyhedra-principles and theoretical studies.

    Science.gov (United States)

    Monakhov, Kirill Yu; Linti, Gerald; Wolters, Lando P; Bickelhaupt, F Matthias

    2011-06-20

    We have quantum chemically investigated the structure, stability, and bonding mechanism in highly aggregated alkali-metal salts of bismuthanediide anions [RBi](2-) using relativistic density functional theory (DFT, at ZORA-BP86/TZ2P) in combination with a quantitative energy decomposition analysis (EDA). Our model systems are alkali-metal-supported bismuth polyhedra [(RBi)(n)M(2n-4)](4-) with unique interpenetrating shells of a bismuth polyhedron and an alkali-metal superpolyhedron. Furthermore, we have analyzed the trianionic inclusion complexes [M'@{(RBi)(n)M(2n-4)}](3-) involving an additional endohedral alkali-metal ion M'. The main objective is to assist the further development of synthetic approaches toward this class of compounds. Our analyses led to electron-counting rules relating, for example, the number of bonding orbitals (N(bond)) of the cage molecules [(RBi)(n)M(2n+Q)](Q) to the number of bismuth atoms (n(Bi)), alkali-metal atoms (n(M)), and net charge Q as N(bond) = n(Bi) + n(M) - Q (R = one-electron donor ligand; M = alkali metal; n = 4-12; Q = -4, -6, -8). Finally, on the basis of our findings, we predict the next members in the 5-fold symmetrical row of alkali-metallobismaspheres with a macroicosahedral arrangement.

  19. Thermochemically evolved nanoplatelets of bismuth selenide with enhanced thermoelectric figure of merit

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Zulfiqar; Cao, Chuanbao, E-mail: cbcao@bit.edu.cn; Butt, Faheem K.; Tahir, Muhammad; Tanveer, M.; Aslam, Imran; Rizwan, Muhammad; Idrees, Faryal; Khalid, Syed [Research Centre of Materials Science, School of Materials Science and Engineering, Beijing Institute of Technology, Beijing 100081 (China); Butt, Sajid [State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China)

    2014-11-15

    We firstly present a simple thermochemical method to fabricate high-quality Bi{sub 2}Se{sub 3} nanoplatelets with enhanced figure of merit using elemental bismuth and selenium powders as precursors. The crystal structure of as synthesized products is characterized via X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and high resolution transmission electron microscopy (HRTEM) measurements. Morphological and chemical synthetic parameters are investigated through a series of experiments; thickness and composition of the platelets are well controlled in large scale production. Subsequently spark plasma sintering (SPS) is performed to fabricate n-type nanostructured bulk thermoelectric materials. Raman Spectroscopy of the two selected samples with approximately of 50 and 100 nm thicknesses shows three vibrational modes. The lower thickness sample exhibits the maximum red shift of about 2.17 cm{sup -1} and maximum broadening of about 10 cm{sup -1} by in-plane vibrational mode E{sup 2}{sub g}. The enhanced value of figure of merit ∼0.41 is obtained for pure phase bismuth selenide to the best of our knowledge. We observe metallic conduction behavior while semiconducting behavior for nanostructured bismuth selenide is reported elsewhere which could be due to different synthetic techniques adopted. These results clearly suggest that our adopted synthetic technique has profound effect on the electronic and thermoelectric transport properties of this material.

  20. Three new bismuth(III) pyridine-2,6-dicarboxylate compounds: Synthesis, characterization and crystal structures

    Science.gov (United States)

    Hakimi, Mohammad; Motieiyan, Elham; Bertolotti, Federica; Marabello, Domenica; Nunes Rodrigues, Vitor Hugo

    2015-11-01

    Three new metal-organic compounds containing bismuth and pyridine-2,6-dicarboxylate (pydc) formulated as (2-apyH)2[Bi(pydc)2(pydcH)]·2H2O, 1, (4-apyH)[Bi(pydc) (pydcH)2].4H2O, 2 and (pipzeaH)[Bi2(pydc)3(pydcH) (H2O)2]·5H2O, 3, (2-apy = 2-aminopyridine, 4-apy = 4-aminopyridine, pipzea = 2-piperazin-1-ylethanamine), have been synthesized in deionized water and characterized by elemental analysis (C, H and N), spectral (UV-Vis, IR), 1H NMR spectroscopy, TGA and single crystal X-ray diffraction. These compounds were obtained via proton transfer methodology. Compounds 1 and 2 have similar monomeric bismuth coordination units, whereas compound 3 has a dimeric bismuth coordination unit. The compounds are anionic in 1 and 2 and they are connected non-covalently to 2-apyH and 4-apyH, respectively. In 3, two molecules are present, one neutral and one anionic, and both are connected non-covalently to pipzeaH cations. Five different coordination modes of Bi-pydc exist in 1, 2 and 3. These compounds are stabilized in the solid state by a complex network of hydrogen bonds between crystallization water molecules, anionic, cationic and neutral fragments, forming 3D-supramolecular arrays.

  1. Light-Emitting Diodes: Learning New Physics

    Science.gov (United States)

    Planinšic, Gorazd; Etkina, Eugenia

    2015-01-01

    This is the third paper in our Light-Emitting Diodes series. The series aims to create a systematic library of LED-based materials and to provide the readers with the description of experiments and pedagogical treatment that would help their students construct, test, and apply physics concepts and mathematical relations. The first paper, published…

  2. Light-Emitting Diodes: Solving Complex Problems

    Science.gov (United States)

    Planinšic, Gorazd; Etkina, Eugenia

    2015-01-01

    This is the fourth paper in our Light-Emitting Diodes series. The series aims to create a systematic library of LED-based materials and to provide readers with the description of experiments and the pedagogical treatment that would help their students construct, test, and apply physics concepts and mathematical relations. The first paper provided…

  3. Light-Emitting Diodes: A Hidden Treasure

    Science.gov (United States)

    Planinšic, Gorazd; Etkina, Eugenia

    2014-01-01

    LEDs, or light-emitting diodes, are cheap, easy to purchase, and thus commonly used in physics instruction as indicators of electric current or as sources of light (Fig. 1). In our opinion LEDs represent a unique piece of equipment that can be used to collect experimental evidence, and construct and test new ideas in almost every unit of a general…

  4. Light-Emitting Diodes: A Hidden Treasure

    Science.gov (United States)

    Planinšic, Gorazd; Etkina, Eugenia

    2014-01-01

    LEDs, or light-emitting diodes, are cheap, easy to purchase, and thus commonly used in physics instruction as indicators of electric current or as sources of light (Fig. 1). In our opinion LEDs represent a unique piece of equipment that can be used to collect experimental evidence, and construct and test new ideas in almost every unit of a general…

  5. Light-Emitting Diodes: Learning New Physics

    Science.gov (United States)

    Planinšic, Gorazd; Etkina, Eugenia

    2015-01-01

    This is the third paper in our Light-Emitting Diodes series. The series aims to create a systematic library of LED-based materials and to provide the readers with the description of experiments and pedagogical treatment that would help their students construct, test, and apply physics concepts and mathematical relations. The first paper, published…

  6. Auger Emitting Radiopharmaceuticals for Cancer Therapy

    Science.gov (United States)

    Falzone, Nadia; Cornelissen, Bart; Vallis, Katherine A.

    Radionuclides that emit Auger electrons have been of particular interest as therapeutic agents. This is primarily due to the short range in tissue, controlled linear paths and high linear energy transfer of these particles. Taking into consideration that ionizations are clustered within several cubic nanometers around the point of decay the possibility of incorporating an Auger emitter in close proximity to the cancer cell DNA has immense therapeutic potential thus making nuclear targeted Auger-electron emitters ideal for precise targeting of cancer cells. Furthermore, many Auger-electron emitters also emit γ-radiation, this property makes Auger emitting radionuclides a very attractive option as therapeutic and diagnostic agents in the molecular imaging and management of tumors. The first requirement for the delivery of Auger emitting nuclides is the definition of suitable tumor-selective delivery vehicles to avoid normal tissue toxicity. One of the main challenges of targeted radionuclide therapy remains in matching the physical and chemical characteristics of the radionuclide and targeting moiety with the clinical character of the tumor. Molecules and molecular targets that have been used in the past can be classified according to the carrier molecule used to deliver the Auger-electron-emitting radionuclide. These include (1) antibodies, (2) peptides, (3) small molecules, (4) oligonucleotides and peptide nucleic acids (PNAs), (5) proteins, and (6) nanoparticles. The efficacy of targeted radionuclide therapy depends greatly on the ability to increase intranuclear incorporation of the radiopharmaceutical without compromising toxicity. Several strategies to achieve this goal have been proposed in literature. The possibility of transferring tumor therapy based on the emission of Auger electrons from experimental models to patients has vast therapeutic potential, and remains a field of intense research.

  7. Solid-phase extraction of galloyl- and caffeoylquinic acids from natural sources (Galphimia glauca and Arnicae flos) using pure zirconium silicate and bismuth citrate powders as sorbents inside micro spin columns.

    Science.gov (United States)

    Hussain, Shah; Schönbichler, Stefan A; Güzel, Yüksel; Sonderegger, Harald; Abel, Gudrun; Rainer, Matthias; Huck, Christian W; Bonn, Günther K

    2013-10-01

    Galloyl- and caffeoylquinic acids are among the most important pharmacological active groups of natural compounds. This study describes a pre-step in isolation of some selected representatives of these groups from biological samples. A selective solid-phase extraction (SPE) method for these compounds may help assign classes and isomer designations within complex mixtures. Pure zirconium silicate and bismuth citrate powders (325 mesh) were employed as two new sorbents for optimized SPE of phenolic acids. These sorbents possess electrostatic interaction sites which accounts for additional interactions for carbon acid moieties as compared to hydrophilic and hydrophobic sorbents alone. Based on this principle, a selective SPE method for 1,3,4,5-tetragalloylquinic acid (an anti-HIV and anti-asthamatic agent) as a starting compound was developed and then deployed upon other phenolic acids with success. The recoveries and selectivities of both sorbents were compared to most commonly applied and commercially available sorbents by using high performance liquid chromatography. The nature of interaction between the carrier sorbent and the acidic target molecules was investigated by studying hydrophilic (silica), hydrophobic (C18), mixed-mode (ionic and hydrophobic: Oasis(®) MAX) and predominantly electrostatic (zirconium silicate) materials. The newly developed zirconium silicate and bismuth citrate stationary phases revealed promising results for the selective extraction of galloyl- and caffeoylquinic acids from natural sources. It was observed that zirconium silicate exhibited maximum recovery and selectivity for tetragalloylquinic acid (84%), chlorogenic acid (82%) and dicaffeoylquinic acid (94%) among all the tested sorbents.

  8. Crystal structures of a pentavalent bismuthate, SrBi2O6 and a lead bismuth oxide (Pb1/3Bi2/3O1.4

    Directory of Open Access Journals (Sweden)

    Nobuhiro Kumada

    2014-06-01

    Full Text Available The crystal structures of a pentavalent bismuthate, SrBi2O6 with the PbSb2O6-type structure and a lead bismuth oxide, (Pb1/3Bi2/3O1.4 with the fluorite-type structure were refined by using neutron diffraction data. The final R-factors were Rwp = 4.49, Rp = 3.46, RI = 4.50 and RF = 1.70% for SrBi2O6 and Rwp = 5.04, Rp = 3.93, RI = 5.47 and RF = 4.26% for (Pb1/3Bi2/3O1.4. SrBi2O6 prepared from NaBiO3·1.4H2O is the first example of the bismuthate with the PbSb2O6-type structure. The fluorite-type lead bismuth oxide, (Pb1/3Bi2/3O1.4 was obtained by heating the PbSb2O6-type lead bismuthate, PbBi2O5.9·H2O which was prepared also from NaBiO3·1.4H2O.

  9. Preparation and characterisation of high-density ionic liquids incorporating halobismuthate anions.

    Science.gov (United States)

    Cousens, Nico E A; Taylor Kearney, Leah J; Clough, Matthew T; Lovelock, Kevin R J; Palgrave, Robert G; Perkin, Susan

    2014-07-28

    A range of ionic liquids containing dialkylimidazolium cations and halobismuthate anions ([BiBr(x)Cl(y)I(z)](-) and [Bi2Br(x)Cl(y)I(z)](-)) were synthesised by combining dialkylimidazolium halide ionic liquids with bismuth(III) halide salts. The majority were room temperature liquids, all with very high densities. The neat ionic liquids and their mixtures with 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide were characterised using Densitometry, Viscometry, NMR Spectroscopy, Electrospray Ionisation Mass Spectrometry (ESI), Liquid Secondary Ion Mass Spectrometry (LSIMS), Matrix-assisted Laser Desorption/Ionization Mass Spectrometry (MALDI), X-Ray Photoelectron Spectroscopy (XPS) and Thermogravimetric Analysis (TGA), to establish their speciation and suitability for high-temperature applications.

  10. Li3PO4 Matrix Enables a Long Cycle Life and High Energy Efficiency Bismuth-Based Battery.

    Science.gov (United States)

    Sun, Chuan-Fu; Hu, Junkai; Wang, Peng; Cheng, Xi-Yuan; Lee, Sang Bok; Wang, YuHuang

    2016-09-14

    Bismuth is a lithium-ion battery anode material that can operate at an equilibrium potential higher than graphite and provide a capacity twice as high as that of Li4Ti5O12, making it intrinsically free from lithium plating that may cause catastrophic battery failure. However, the potential of bismuth is hampered by its inferior cyclability (limited to tens of cycles). Here, we propose an "ion conductive solid-state matrix" approach to address this issue. By homogeneously confining bismuth nanoparticles in a solid-state γ-Li3PO4 matrix that is electrochemically formed in situ, the resulting composite anode exhibits a reversible capacity of 280 mA hours per gram (mA h/g) at a rate of 100 mA/g and a record cyclability among bismuth-based anodes up to 500 cycles with a capacity decay rate of merely 0.071% per cycle. We further show that full-cell batteries fabricated from this composite anode and commercial LiFePO4 cathode deliver a stable cell voltage of ∼2.5 V and remarkable energy efficiency up to 86.3%, on par with practical batteries (80-90%). This work paves a way for harnessing bismuth-based battery chemistry for the design of high capacity, safer lithium-ion batteries to meet demanding applications such as electric vehicles.

  11. Market Liquidity and Funding Liquidity

    OpenAIRE

    Brunnermeier, Markus K; Lasse Heje Pedersen

    2007-01-01

    We provide a model that links an asset's market liquidity - i.e., the ease with which it is traded - and traders' funding liquidity - i.e., the ease with which they can obtain funding. Traders provide market liquidity, and their ability to do so depends on their availability of funding. Conversely, traders' funding, i.e., their capital and the margins they are charged, depend on the assets' market liquidity. We show that, under certain conditions, margins are destabilizing and market liquidit...

  12. Market Liquidity and Funding Liquidity

    OpenAIRE

    Markus K. Brunnermeier; Lasse Heje Pedersen

    2007-01-01

    We provide a model that links an asset's market liquidity - i.e., the ease with which it is traded - and traders' funding liquidity - i.e., the ease with which they can obtain funding. Traders provide market liquidity, and their ability to do so depends on their availability of funding. Conversely, traders' funding, i.e., their capital and the margins they are charged, depend on the assets' market liquidity. We show that, under certain conditions, margins are destabilizing and market liquidit...

  13. Ultrasonic vocalizations emitted by flying squirrels.

    Directory of Open Access Journals (Sweden)

    Meghan N Murrant

    Full Text Available Anecdotal reports of ultrasound use by flying squirrels have existed for decades, yet there has been little detailed analysis of their vocalizations. Here we demonstrate that two species of flying squirrel emit ultrasonic vocalizations. We recorded vocalizations from northern (Glaucomys sabrinus and southern (G. volans flying squirrels calling in both the laboratory and at a field site in central Ontario, Canada. We demonstrate that flying squirrels produce ultrasonic emissions through recorded bursts of broadband noise and time-frequency structured frequency modulated (FM vocalizations, some of which were purely ultrasonic. Squirrels emitted three types of ultrasonic calls in laboratory recordings and one type in the field. The variety of signals that were recorded suggest that flying squirrels may use ultrasonic vocalizations to transfer information. Thus, vocalizations may be an important, although still poorly understood, aspect of flying squirrel social biology.

  14. Principles of phosphorescent organic light emitting devices.

    Science.gov (United States)

    Minaev, Boris; Baryshnikov, Gleb; Agren, Hans

    2014-02-07

    Organic light-emitting device (OLED) technology has found numerous applications in the development of solid state lighting, flat panel displays and flexible screens. These applications are already commercialized in mobile phones and TV sets. White OLEDs are of especial importance for lighting; they now use multilayer combinations of organic and elementoorganic dyes which emit various colors in the red, green and blue parts of the visible spectrum. At the same time the stability of phosphorescent blue emitters is still a major challenge for OLED applications. In this review we highlight the basic principles and the main mechanisms behind phosphorescent light emission of various classes of photofunctional OLED materials, like organic polymers and oligomers, electron and hole transport molecules, elementoorganic complexes with heavy metal central ions, and clarify connections between the main features of electronic structure and the photo-physical properties of the phosphorescent OLED materials.

  15. Vertical-Cavity Surface-Emitting Lasers

    Science.gov (United States)

    Wilmsen, Carl W.; Temkin, Henryk; Coldren, Larry A.

    2002-01-01

    1. Introduction to VCSELs L. A. Coldren, C. W. Wilmsen and H. Temkin; 2. Fundamental issues in VCSEL design L. A. Coldren and Eric R. Hegblom; 3. Enhancement of spontaneous emission in microcavities E. F. Schubert and N. E. J. Hunt; 4. Epitaxy of vertical-cavity lasers R. P. Schneider Jr and Y. H. Young; 5. Fabrication and performance of vertical-cavity surface-emitting lasers Kent D. Choquette and Kent Geib; 6. Polarization related properties of vertical cavity lasers Dmitri Kuksenkov and Henryk Temkin; 7. Visible light emitting vertical cavity lasers Robert L. Thornton; 8. Long-wavelength vertical-cavity lasers Dubrakovo I. Babic, Joachim Piprek and John E. Bowers; 9. Overview of VCSEL applications Richard C. Williamson; 10. Optical interconnection applications and required characteristics Kenichi Kasahara; 11. VCSEL-based fiber-optic data communications Kenneth Hahn and Kirk Giboney; 12. VCSEL-based smart pixels for free space optoelectronic processing C. W. Wilmsen.

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

    Science.gov (United States)

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

    2015-06-01

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

  17. Safety of light emitting diodes in toys.

    Science.gov (United States)

    Higlett, M P; O'Hagan, J B; Khazova, M

    2012-03-01

    Light emitting diodes (LEDs) are increasingly being used in toys. An assessment methodology is described for determining the accessible emission limits for the optical radiation from the toys, which takes account of expected use and reasonably foreseeable misuse of toys. Where data are available, it may be possible to assess the toy from the data sheet alone. If this information is not available, a simple measurement protocol is proposed.

  18. Does antimatter emit a new light?

    Science.gov (United States)

    Santilli, Ruggero Maria

    1997-08-01

    Contemporary theories of antimatter have a number of insufficiencies which stimulated the recent construction of the new isodual theory based on a certain anti-isomorphic map of all (classical and quantum) formulations of matter called isoduality. In this note we show that the isodual theory predicts that antimatter emits a new light, called isodual light, which can be distinguished from the ordinary light emitted by matter via gravitational interactions (only). In particular, the isodual theory predicts that all stable antiparticles such as the isodual photon, the positron and the antiproton experience antigravity in the field of matter (defined as the reversal of the sign of the curvature tensor). The antihydrogen atom is therefore predicted to: experience antigravity in the field of Earth; emit the isodual photon; and have the same spectroscopy of the hydrogen atom, although subjected to an anti-isomorphic isodual map. In this note we also show that the isodual theory predicts that bound states of elementary particles and antiparticles (such as the positronium) experience ordinary gravitation in both fields of matter and antimatter, thus bypassing known objections against antigravity. A number of intriguing and fundamental, open theoretical and experimental problems of “the new physics of antimatter” are pointed out.

  19. Researches of odour emitted by household waste

    Directory of Open Access Journals (Sweden)

    Eglė Marčiulaitienė

    2015-10-01

    Full Text Available The article deals with odour emitted by household waste, the chemical composition of household waste. The experiment was made with food waste (1000 g placed in 5 litter containers. Food waste was containing products of animal origin (meat, fish, dairy products and plant origin (vegetables, fruit waste. Time of the experiment was 14 days 19±3 °C at environment temperature. Odour concentration is determined by dynamic olfactometry method. Studies have shown that the strongest odour of all household waste used in this experiment was emitted by meat and fish waste (76 444 OUE/m3. Meat and fish waste emits the strongest odour as waste contains proteins, their decomposition releases into the environment a strong unpleasant odour, hydrogen sulphide and ammonia. Protein degradation releases into the environment are, characterized by a strong unpleasant smell of hydrogen sulphide and ammonia gas. During the anaerobic decomposition of organic matter a variety of other fragrant compounds: alcohols (e.g., ethanol and methanol, vinegar, formic acid, etc. is found.

  20. Hydrothermal synthesis and crystal structure of a new lithium copper bismuth oxide, LiCuBiO4

    Science.gov (United States)

    Kumada, Nobuhiro; Nakamura, Ayumi; Miura, Akira; Takei, Takahiro; Azuma, Masaki; Yamamoto, Hajime; Magome, Eisuke; Moriyoshi, Chikako; Kuroiwa, Yoshihiro

    2017-01-01

    A new lithium copper bismuth oxide, LiCuBiO4 was prepared by hydrothermal reaction using NaBiO30.1*4H2O. The crystal structural model of this compound was refined by using synchrotron X-ray powder diffraction data. This bismuthate has the LiCuSbO4 related structure with the orthorhombic cell (Space group: Pnma) of a=10.9096(9), b=5.8113(5) and c=5.0073(4) Å, and the final R-factors were Rwp=4.84 and Rp=3.58%. This compound is the first example of a lithium copper bismuthate containing Bi5+. An antiferromagnetic ordering of Cu2+ moment was observed at 6 K.