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Sample records for aluminium gallium indium

  1. Tetrahedral homonuclear organoelement clusters and subhalides of aluminium, gallium and indium

    Science.gov (United States)

    Uhl, Werner

    This review is focused on the synthesis and the reactivity of tetrahedral organoelement clusters of the heavier elements of third main-group aluminium, gallium, and indium, which have been known for about a decade. They possess the elements in an unusually low oxidation state of +1 and have direct element-element interactions between their four constituents. Each cluster atom is further attached to one terminal and in most cases a bulky organic substituent, which prevents disproportionation by steric shielding. The synthesis of these compounds succeeds by different methods such as the reduction of suitable organoelement(III) halides with alkali metals and magnesium or the treatment of element(I) halides with lithium organyls. They are deeply coloured, and their bonding situation may best be described by delocalized molecular orbitals. They show a singular chemical reactivity, which results in the formation of many secondary products possessing unprecedented structures and properties. The synthesis of organoelement subhalides still containing the elements in low oxidation states is discussed in more detail in the second part of this review. These compounds are easily accessible by the careful oxidation of the clusters with halogen donors such as hexachloroethane or with AlX3/X2 mixtures. They produce dimers via halogen bridges, but in certain cases monomers were observed even for the solid state. They are very effective starting compounds for secondary reactions and the generation of new products containing the elements in unusual oxidation states by salt-elimination reactions, for instance.

  2. Extraction chromatography of aluminium(Ⅲ) and mutual separation of aluminium ( Ⅲ ) , gallium ( Ⅲ ), indium ( Ⅲ )and thallium ( Ⅲ ) with N-n-octylaniline%Extraction chromatography of aluminium(Ⅲ) and mutual separation of aluminium ( Ⅲ ),gallium ( Ⅲ ),indium ( Ⅲ )and thallium ( Ⅲ ) with N-n-octylaniline

    Institute of Scientific and Technical Information of China (English)

    Sachin R PHULE; Haribhau R AHER; Shashikant R KUCHEKAR; Sung-H HAN

    2012-01-01

    A selective method has been developed for the extraction chromatography of aluminium (Ⅲ) and its separation from several metal ions with a chromatographic column containing N-n-octylaniline (a liquid anion exchanger) coated on silanized silica gel as a stationary phase.The aluminium (Ⅲ) was quantitatively extracted with the 0.065 mol/L N-n-octylaniline in 0.013 to 0.05 mol/L sodium succinate at a flow rate of 1.0 mL/min.The extracted metal ion has been recovered by eluting with 25.0 mL of 0.05 mol/L hydrochloric acid and estimated spectrophotometrically with aurintricarboxylic acid.The effects of the acid concentration,the reagent concentration,the flow rate and the eluting agents have been investigated.The log-log plots of distribution coefficient ( Kd ( Al (Ⅲ ) ) ) versus N-n-octylaniline concentration in 0.005 and 0.007 mol/L sodium succinate gave the slopes of 0.5 and 0.7 respectively and showed the probable composition of the extracted species was 1∶1 (metal to amine ratio) and the nature of extracted species was [ RR'NH2+ Al succinate2- ] org.The extraction of aluminium(Ⅲ) was carried out in the presence of various ions to ascertain the tolerance limit of individual ions.Aluminium (Ⅲ) has been separated from multicomponent mixtures,pharmaceutical samples and synthetic mixtures corresponding to alloys.A scheme for mutual separation of aluminium (Ⅲ),indium (Ⅲ),gallium (Ⅲ) and thallium(Ⅲ) has been developed by using suitable masking agents.The method is fast,accurate and precise.

  3. Chemico-analytical properties and extraction of aluminium gallium and indium complexes with glycine cresol red

    International Nuclear Information System (INIS)

    It is established that glycine cresol red (GCR) forms coloured complexes with Al3+, Ga3+ and In3+ ions in aqueous solutions. The optimum conditions of their formation and their composition are determined. Introduction of acetate-ions into solution hampers the formation of coloured compounds of In and Al. High selectivity of CCR action is achieved during the extraction of complexes with chloroform solution of α-bromobutyric acid. The optimum conditions of extraction are studied, the composition and extraction constant of gallium complex with GCR and α-bromobutyric acid are determined

  4. Formazanido complexes of heavier group 13 elements aluminium, gallium, and indium.

    Science.gov (United States)

    Schorn, W; Grosse-Hagenbrock, D; Oelkers, B; Sundermeyer, J

    2016-01-21

    The preparation, molecular structures and physical properties of novel heavy group 13 metal formazanido complexes are described. The trimethyl derivatives MMe3 (M = Al, Ga, In) react with 1,3,5-triphenylformazan (Htpf) in a 1 : 1 ratio to give methane and metallacycles of the type [M(tpf)Me2]. While [Al(tpf)Me2] and [Ga(tpf)Me2] are mononuclear compounds with six-membered rings and coordination number 4 in solution and in the crystalline state, indium derivative [In(tpf)Me2] forms oligomers in non-coordinating solvents according to NMR studies, these are probably N-bridged dimers with coordination number 5 at indium. The oligomer is cleaved by addition of one equivalent of pyridine or 4-dimethylaminopyridine (DMAP). The complexes [M(tpf)Me2] (M = Al, Ga) and [In(tpf)Me2(DMAP)] are characterized by XRD analyses. They are unique examples of main group metal formazane ring systems of the third and higher periods. The UV-Vis solution spectra of the neutral ligand Htpf and its metallated compounds [M(tpf)Me2] (M = Al, Ga, In) are discussed. PMID:26658885

  5. Growth and characterization of indium antimonide and gallium antimonide crystals

    Indian Academy of Sciences (India)

    N K Udayashankar; H L Bhat

    2001-10-01

    Indium antimonide and gallium antimonide were synthesized from the respective component elements using an indigenously fabricated synthesis unit. Bulk crystals of indium antimonide and gallium antimonide were grown using both the vertical and horizontal Bridgman techniques. Effect of ampoule shapes and diameters on the crystallinity and homogeneity was studied. The grown crystals were characterized using X-ray analysis, EDAX, chemical etching, Hall effect and conductivity measurements. In the case of gallium antimonide, effect of dopants (Te and In) on transport and photoluminescence properties was investigated.

  6. Indium Phosphide Window Layers for Indium Gallium Arsenide Solar Cells

    Science.gov (United States)

    Jain, Raj K.

    2005-01-01

    Window layers help in reducing the surface recombination at the emitter surface of the solar cells resulting in significant improvement in energy conversion efficiency. Indium gallium arsenide (In(x)Ga(1-x)As) and related materials based solar cells are quite promising for photovoltaic and thermophotovoltaic applications. The flexibility of the change in the bandgap energy and the growth of InGaAs on different substrates make this material very attractive for multi-bandgap energy, multi-junction solar cell approaches. The high efficiency and better radiation performance of the solar cell structures based on InGaAs make them suitable for space power applications. This work investigates the suitability of indium phosphide (InP) window layers for lattice-matched In(0.53)Ga(0.47)As (bandgap energy 0.74 eV) solar cells. We present the first data on the effects of the p-type InP window layer on p-on-n lattice-matched InGaAs solar cells. The modeled quantum efficiency results show a significant improvement in the blue region with the InP window. The bare InGaAs solar cell performance suffers due to high surface recombination velocity (10(exp 7) cm/s). The large band discontinuity at the InP/InGaAs heterojunction offers a great potential barrier to minority carriers. The calculated results demonstrate that the InP window layer effectively passivates the solar cell front surface, hence resulting in reduced surface recombination and therefore, significantly improving the performance of the InGaAs solar cell.

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

    Science.gov (United States)

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

    2011-11-15

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

  8. Synthesis and purification of trialkyl compounds of gallium and indium

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The research progress in trialkyl compounds of gallium and indium was discussed from two aspects, one was the chemical synthesis of the compounds and the other was the purification of them. There are three synthesis routes being reported in the first aspect, i.e. the route staring from pure metal, the route starting from the pure metal trihalides, and the electrochemical route. In the second aspect, the purifying methods of decomposition-distillation and zone refining were reviewed.

  9. Effect of oxidation on the Mechanical Properties of Liquid Gallium and Eutectic Gallium-Indium

    CERN Document Server

    Xu, Qin; Guo, Qiti; Jaeger, Heinrich; Brown, Eric

    2012-01-01

    Liquid metals exhibit remarkable mechanical properties, in particular large surface tension and low viscosity. However, these properties are greatly affected by oxidation when exposed to air. We measure the viscosity, surface tension, and contact angle of gallium (Ga) and a eutectic gallium-indium alloy (eGaIn) while controlling such oxidation by surrounding the metal with an acid bath of variable concentration. Rheometry measurements reveal a yield stress directly attributable to an oxide skin that obscures the intrinsic behavior of the liquid metals. We demonstrate how the intrinsic viscosity can be obtained with precision through a scaling technique that collapses low- and high-Reynolds number data. Measuring surface tension with a pendant drop method, we show that the oxide skin generates a surface stress that mimics surface tension and develop a simple model to relate this to the yield stress obtained from rheometry. We find that yield stress, surface tension, and contact angle all transition from solid-...

  10. Regularities in aluminium and indium chemisorption on chelating polymeric sorbents

    International Nuclear Information System (INIS)

    Complexation properties of synthesized polymer chelate sorbents: substituted of polystyrene-azo-pyrocatechol are investigated and correlations between pK'OH of functional groups of sorbents as well as pH50 values of chelation and constants of stability (lgKstab) are established for studying regularities of effect of structure and acid-base properties of functional groups of sorbents on the parameters of Al3+ and In3+ chemical sorption. Established correlations make it possible to predict the physicochemical parameters of sorbents and sorption of metal ions with the aim of separation and concentration of aluminium and indium micro account from the objects of different origin

  11. Fractal characteristics of nanocrystalline indium and gallium sulfide particles

    Energy Technology Data Exchange (ETDEWEB)

    Sastry, P.U., E-mail: psastry@barc.gov.i [Solid State Physics Division, Mumbai 400085 (India); Dutta, Dimple P. [Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2009-11-13

    The structure of nano-sized powders of indium sulfide (In{sub 2}S{sub 3}) and gallium sulfide (Ga{sub 2}S{sub 3}), prepared by single source precursor route has been investigated by small angle X-ray scattering technique. The particle morphology shows interesting fractal nature. For In{sub 2}S{sub 3}, the nanoparticle aggregates show a mass fractal with fractal dimension 2.0 that increases with longer time of thermal treatment. Below the length scale of about 20 nm, the particles have a rough surface with a surface fractal dimension of 2.8. Unlike In{sub 2}S{sub 3}, structure of Ga{sub 2}S{sub 3} exhibits a single surface fractal over whole q-range of study. The estimated particle sizes are in range of 5-15 nm and the results are supported by transmission electron microscope.

  12. Formation of Flexible and Transparent Indium Gallium Zinc Oxide/Ag/Indium Gallium Zinc Oxide Multilayer Film

    Science.gov (United States)

    Kim, Jun Ho; Kim, Da-Som; Kim, Sun-Kyung; Yoo, Young-Zo; Lee, Jeong Hwan; Kim, Sang-Woo; Seong, Tae-Yeon

    2016-05-01

    In this study, the electrical, optical, and bending characteristics of amorphous indium gallium zinc oxide (IGZO)/Ag/IGZO (39 nm/19 nm/39 nm) multilayer films deposited on polyethylene terephthalate (PET) substrate at room temperature were investigated and compared with those of Sn-doped indium oxide (ITO) (100 nm thick) films. At 500 nm the ITO film transmitted 91.3% and the IGZO/Ag/IGZO multilayer film transmitted 88.8%. The calculated transmittance spectrum of the multilayer film was similar to the experimental result. The ITO film and IGZO/Ag/IGZO multilayer film, respectively, showed carrier concentrations of 1.79 × 1020 and 7.68 × 1021 cm-3 and mobilities of 27.18 cm2/V s and 18.17 cm2/V s. The ITO film had a sheet resistance of 134.9 Ω/sq and the IGZO/Ag/IGZO multilayer film one of 5.09 Ω/sq. Haacke's figure of merit (FOM) was calculated to be 1.94 × 10-3 for the ITO film and 45.02 × 10-3 Ω-1 for the IGZO/Ag/IGZO multilayer film. The resistance change of 100 nm-thick ITO film was unstable even after five cycles, while that of the IGZO/Ag/IGZO film was constant up to 1000 cycles.

  13. Formation of Flexible and Transparent Indium Gallium Zinc Oxide/Ag/Indium Gallium Zinc Oxide Multilayer Film

    Science.gov (United States)

    Kim, Jun Ho; Kim, Da-Som; Kim, Sun-Kyung; Yoo, Young-Zo; Lee, Jeong Hwan; Kim, Sang-Woo; Seong, Tae-Yeon

    2016-08-01

    In this study, the electrical, optical, and bending characteristics of amorphous indium gallium zinc oxide (IGZO)/Ag/IGZO (39 nm/19 nm/39 nm) multilayer films deposited on polyethylene terephthalate (PET) substrate at room temperature were investigated and compared with those of Sn-doped indium oxide (ITO) (100 nm thick) films. At 500 nm the ITO film transmitted 91.3% and the IGZO/Ag/IGZO multilayer film transmitted 88.8%. The calculated transmittance spectrum of the multilayer film was similar to the experimental result. The ITO film and IGZO/Ag/IGZO multilayer film, respectively, showed carrier concentrations of 1.79 × 1020 and 7.68 × 1021 cm-3 and mobilities of 27.18 cm2/V s and 18.17 cm2/V s. The ITO film had a sheet resistance of 134.9 Ω/sq and the IGZO/Ag/IGZO multilayer film one of 5.09 Ω/sq. Haacke's figure of merit (FOM) was calculated to be 1.94 × 10-3 for the ITO film and 45.02 × 10-3 Ω-1 for the IGZO/Ag/IGZO multilayer film. The resistance change of 100 nm-thick ITO film was unstable even after five cycles, while that of the IGZO/Ag/IGZO film was constant up to 1000 cycles.

  14. Low-threshold indium gallium nitride quantum dot microcavity lasers

    Science.gov (United States)

    Woolf, Alexander J.

    Gallium nitride (GaN) microcavities with embedded optical emitters have long been sought after as visible light sources as well as platforms for cavity quantum electrodynamics (cavity QED) experiments. Specifically, materials containing indium gallium nitride (InGaN) quantum dots (QDs) offer an outstanding platform to study light matter interactions and realize practical devices, such as on-chip light emitting diodes and nanolasers. Inherent advantages of nitride-based microcavities include low surface recombination velocities, enhanced room-temperature performance (due to their high exciton binding energy, as high as 67 meV for InGaN QDs), and emission wavelengths in the blue region of the visible spectrum. In spite of these advantages, several challenges must be overcome in order to capitalize on the potential of this material system. Such diffculties include the processing of GaN into high-quality devices due to the chemical inertness of the material, low material quality as a result of strain-induced defects, reduced carrier recombination effciencies due to internal fields, and a lack of characterization of the InGaN QDs themselves due to the diffculty of their growth and therefore lack of development relative to other semiconductor QDs. In this thesis we seek to understand and address such issues by investigating the interaction of light coupled to InGaN QDs via a GaN microcavity resonator. Such coupling led us to the demonstration of the first InGaN QD microcavity laser, whose performance offers insights into the properties and current limitations of the nitride materials and their emitters. This work is organized into three main sections. Part I outlines the key advantages and challenges regarding indium gallium nitride (InGaN) emitters embedded within gallium nitride (GaN) optical microcavities. Previous work is also discussed which establishes context for the work presented here. Part II includes the fundamentals related to laser operation, including the

  15. Deep subgap feature in amorphous indium gallium zinc oxide: Evidence against reduced indium

    Energy Technology Data Exchange (ETDEWEB)

    Sallis, Shawn; Williams, Deborah S. [Materials Science and Engineering, Binghamton University, Binghamton, New York, 13902 (United States); Quackenbush, Nicholas F.; Senger, Mikell [Department of Physics, Applied Physics and Astronomy, Binghamton University, Binghamton, New York, 13902 (United States); Woicik, Joseph C. [Materials Science and Engineering Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland, 20899 (United States); White, Bruce E.; Piper, Louis F.J. [Materials Science and Engineering, Binghamton University, Binghamton, New York, 13902 (United States); Department of Physics, Applied Physics and Astronomy, Binghamton University, Binghamton, New York, 13902 (United States)

    2015-07-15

    Amorphous indium gallium zinc oxide (a-IGZO) is the archetypal transparent amorphous oxide semiconductor. Despite the gains made with a-IGZO over amorphous silicon in the last decade, the presence of deep subgap states in a-IGZO active layers facilitate instabilities in thin film transistor properties under negative bias illumination stress. Several candidates could contribute to the formation of states within the band gap. Here, we present evidence against In{sup +} lone pair active electrons as the origin of the deep subgap features. No In{sup +} species are observed, only In{sup 0} nano-crystallites under certain oxygen deficient growth conditions. Our results further support under coordinated oxygen as the source of the deep subgap states. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  16. Gallium(III) and indium(III) dithiolate complexes: Versatile precursors for metal sulfides

    Indian Academy of Sciences (India)

    Shamik Ghoshal; Vimal K Jain

    2007-11-01

    The chemistry of classical and organometallic complexes of gallium and indium with dithiolate ligands, i.e., dithiocarboxylates, xanthates, dithiocarbamates, dithiophosphates, dithiophophinates and dithioarsenates, has been reviewed. Synthesis, spectroscopic and structural aspects of these complexes are described. Their emerging role as single source molecular precursors for the preparation of metal sulfide thin films and nano-particles has been discussed.

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

    Directory of Open Access Journals (Sweden)

    Zulkepli Afzam

    2016-01-01

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

  18. Effect of heat treatment on anodic activation of aluminium by trace element indium

    Energy Technology Data Exchange (ETDEWEB)

    Graver, Brit [Department of Materials Science and Engineering, Norwegian University of Science and Technology, N-7491 Trondheim (Norway); Helvoort, Antonius T.J. van [Department of Physics, Norwegian University of Science and Technology, N-7491 Trondheim (Norway); Nisancioglu, Kemal, E-mail: kemal.nisancioglu@material.ntnu.n [Department of Materials Science and Engineering, Norwegian University of Science and Technology, N-7491 Trondheim (Norway)

    2010-11-15

    Research highlights: {yields} Indium segregation activates AlIn alloy surface anodically in chloride solution. {yields} Enrichment of In on Al surface can occur thermally by heat treatment at 300 {sup o}C. {yields} Increasing temperature homogenises indium in aluminium reducing anodic activation. {yields} Indium can activate AlIn surface by segregating through dealloying of aluminium. {yields} Anodic activation is caused by AlIn amalgam formation at aluminium surface. - Abstract: The presence of trace elements in Group IIIA-VA is known to activate aluminium anodically in chloride environment. The purpose of this paper is to investigate the surface segregation of trace element In by heat treatment and resulting surface activation. Model binary AlIn alloys, containing 20 and 1000 ppm by weight of In, were characterized after heat treatment at various temperatures by use of glow discharge optical emission spectroscopy, electron microscopy and electrochemical polarization. Heat treatment for 1 h at 300 {sup o}C gave significant segregation of discrete In particles (thermal segregation), which activated the surface. Indium in solid solution with aluminium, obtained by 1 h heat treatment at 600 {sup o}C, also activated by surface segregation of In on alloy containing 1000 ppm In, resulting from the selective dissolution of the aluminium component during anodic oxidation (anodic segregation). The effect of anodic segregation was reduced by decreasing indium concentration in solid solution; it had negligible effect at the 20 ppm level. The segregated particles were thought to form a liquid phase alloy with aluminium during anodic polarization, which in turn, together with the chloride in the solution destabilized the oxide.

  19. Effect of refractory metal diselenides coatings structure on tribodiffusion of gallium and indium

    International Nuclear Information System (INIS)

    Mechanism of gallium and indium saturation of coatings of tungsten, molybdenum and niobium diselenides at their treatment in Ga-In system cavitating eutectic melt is investigated. It is defined, that the main factor, which determines mass transfer of gallium and indium under the effect of ultrasound, is the formation of defect structure by dislocation mechanism for WSe2 and MoSe2 compounds with stoichiometric composition. Coating texture affects the direction of mass transfer by intergranular boundaries. Using NbSe2 coating as an example it is shown, that deviation of compound composition from stoichiometry results in variation of diffusion mechanism: high amount of grain structure defects promotes realization of mass transfer by both their boundaries and volume. Role of coating texture in this case is unessential

  20. Thermodynamic properties of uranium in liquid gallium, indium and their alloys

    International Nuclear Information System (INIS)

    Highlights: • Thermodynamics of uranium is determined in alloys with Ga, In and their mixtures. • In Ga–In alloys decreasing temperature leads to increasing interaction of U with Ga. • Activity coefficients of uranium decrease with increasing gallium content. - Abstract: Activity, activity coefficients and solubility of uranium was determined in gallium, indium and gallium–indium alloys containing 21.8 (eutectic), 40 and 70 wt.% In. Activity was measured at 573–1073 K employing the electromotive force method, and solubility between room temperature (or the alloy melting point) and 1073 K employing direct physical measurements. Activity coefficients were obtained from the difference of experimentally determined temperature dependencies of uranium activity and solubility. Intermetallic compounds formed in the respective alloys were characterized using X-ray diffraction. Partial and excess thermodynamic functions of uranium in the studied alloys were calculated. Liquidus lines in U–Ga and U–In phase diagrams from the side rich in gallium or indium are proposed

  1. Investigation of an Electrochemical Method for Separation of Copper, Indium, and Gallium from Pretreated CIGS Solar Cell Waste Materials

    Directory of Open Access Journals (Sweden)

    Anna M. K. Gustafsson

    2015-01-01

    Full Text Available Recycling of the semiconductor material copper indium gallium diselenide (CIGS is important to ensure a future supply of indium and gallium, which are relatively rare and therefore expensive elements. As a continuation of our previous work, where we recycled high purity selenium from CIGS waste materials, we now show that copper and indium can be recycled by electrodeposition from hydrochloric acid solutions of dissolved selenium-depleted material. Suitable potentials for the reduction of copper and indium were determined to be −0.5 V and −0.9 V (versus the Ag/AgCl reference electrode, respectively, using cyclic voltammetry. Electrodeposition of first copper and then indium from a solution containing the dissolved residue from the selenium separation and ammonium chloride in 1 M HCl gave a copper yield of 100.1 ± 0.5% and an indium yield of 98.1 ± 2.5%. The separated copper and indium fractions contained no significant contamination of the other elements. Gallium remained in solution together with a small amount of indium after the separation of copper and indium and has to be recovered by an alternative method since electrowinning from the chloride-rich acid solution was not effective.

  2. Organo-gallium and indium complexes with dithiolate and oxo ligands: Synthesis, structures and applications

    Indian Academy of Sciences (India)

    Vimal K Jain; Amey Wadawale; Nisha P Kushwah; Manoj K Pal

    2011-03-01

    The chemistry of organo-gallium and indium complexes with dithiolate and internally functionalised oxo ligands has been explored. With 1,1-dithiolate ligands both classical and organometallic complexes of gallium and indium, [M(S$^\\cap$S)3], [RM(S$^\\cap$S)2] and [R2M(S$^\\cap$S)] (where R = Me or Et; M = Ga or In; S$^\\cap$S = RCS2, ROCS2, R2NCS2 and (RO)2PS2) have been isolated. Reactions of internally functionalised oxo ligands with R3MR$\\cdot$OEt2 afforded diorganometal complexes [R2ML]. Molecular structures of several of these complexes have been established by single crystal X-ray diffraction analyses. Complexes derived from oxo ligands showed photoluminescence. They have been used as alkylating agents for C-C coupling reactions of aryl bromides in the presence of PdCl2(PPh3)2. Indium dithiolate complexes have been used as molecular precursors for the preparation of mono dispersed ẞ-In2S3 nanoparticles.

  3. Thermodynamics and separation factor of uranium from lanthanum in liquid eutectic gallium-indium alloy/molten salt system

    International Nuclear Information System (INIS)

    Highlights: • The behavior of lanthanum and uranium on liquid gallium-indium eutectic alloy was carried out. The experiments were done in fused 3LiCl-2KCl eutectic vs. Cl−/Cl2 reference electrode at the temperature range 723–823 K. Thermodynamic properties of La-Ga-In and U-Ga-In alloys and the separation factor U/La were calculated. - Abstract: This work presents the electrochemical study of lanthanum and uranium compounds in fused 3LiCl-2KCl eutectic vs. Cl−/Cl2 reference electrode in the temperature range 723–823 K on liquid gallium-indium eutectic alloy. Thermodynamics and the activity coefficients of lanthanum and uranium were studied. The separation factor of uranium from lanthanum on gallium-indium eutectic alloy was determined

  4. Distinctive Signature of Indium Gallium Nitride Quantum Dot Lasing in Microdisks Cavities

    CERN Document Server

    Woolf, Alexander; Aharanovich, Igor; Zhu, Tongtong; Niu, Nan; Wang, Danqing; Oliver, Rachel A; Hu, Evelyn L

    2014-01-01

    Low threshold lasers realized within compact, high quality optical cavities enable a variety of nanophotonics applications. Gallium nitride (GaN) materials containing indium gallium nitride (InGaN) quantum dots and quantum wells offer an outstanding platform to study light matter interactions and realize practical devices such as efficient light emitting diodes and nanolasers. Despite progress in the growth and characterization of InGaN quantum dots, their advantages as the gain medium in low threshold lasers have not been clearly demonstrated. This work seeks to better understand the reasons for these limitations by focusing on the simpler, limited-mode microdisk cavities, and by carrying out comparisons of lasing dynamics in those cavities using varying gain media including InGaN quantum wells, fragmented quantum wells, and a combination of fragmented quantum wells with quantum dots. For each gain medium, we utilize the distinctive, high quality (Q~5500) modes of the cavities, and the change in the highest ...

  5. Gallium and Indium: which to use when 2. Nuclear medicine imaging of osteomyelitis

    International Nuclear Information System (INIS)

    Nuclear medicine studies have become increasingly clinically utilized in the diagnostic approach to suspected osteomyelitis. The technetium-99m phosphonate bone scan, with the three- or four-phase modification designed to distinguish between osteomyelitis and cellulitis, the gallium-67 citrate scan, and the indium-111 leukocyte scan. have demonstrated utility in diagnosing acute osteomyelitis or exacerbation of chronic osteomyelitis and monitoring the response to therapy in those patients. Computed tomography and magnetic resonance imaging of suspected osteomyelitis continue to be evaluated, but available data indicate that these modalities play a supporting role to radionuclide studies. 34 refs., 3 figs

  6. Thermodynamic properties of lanthanum in gallium-indium eutectic based alloys

    OpenAIRE

    Shchetinskiy, A. V.; Dedyukhin, A. S.; Volkovich, V. A.; Yamshchikov, L. F.; Maisheva, A. I.; Osipenko, A. G.; Kormilitsyn, M. V.

    2013-01-01

    Activity and activity coefficients of lanthanum were determined for the first time in gallium-indium eutectic based alloys in a wide temperature range employing electromotive force method. Activity of β-La and super cooled liquid lanthanum in Ga-In eutectic based alloys between 573 and 1073 K linearly depends on the reciprocal temperature: lgaβ-La(Ga-In)=5.660-15, 352T±0.093 lgaLa(Ga-In)=6.074-15,839T±0.093 Activity coefficients of β-La and super cooled liquid lanthanum in this system at 617-...

  7. Paired-pulse facilitation achieved in protonic/electronic hybrid indium gallium zinc oxide synaptic transistors

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Li Qiang, E-mail: guoliqiang@ujs.edu.cn; Ding, Jian Ning; Huang, Yu Kai [Micro/Nano Science & Technology Center, Jiangsu University, Zhenjiang, 212013 (China); Zhu, Li Qiang, E-mail: lqzhu@nimte.ac.cn [Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China)

    2015-08-15

    Neuromorphic devices with paired pulse facilitation emulating that of biological synapses are the key to develop artificial neural networks. Here, phosphorus-doped nanogranular SiO{sub 2} electrolyte is used as gate dielectric for protonic/electronic hybrid indium gallium zinc oxide (IGZO) synaptic transistor. In such synaptic transistors, protons within the SiO{sub 2} electrolyte are deemed as neurotransmitters of biological synapses. Paired-pulse facilitation (PPF) behaviors for the analogous information were mimicked. The temperature dependent PPF behaviors were also investigated systematically. The results indicate that the protonic/electronic hybrid IGZO synaptic transistors would be promising candidates for inorganic synapses in artificial neural network applications.

  8. Paired-pulse facilitation achieved in protonic/electronic hybrid indium gallium zinc oxide synaptic transistors

    International Nuclear Information System (INIS)

    Neuromorphic devices with paired pulse facilitation emulating that of biological synapses are the key to develop artificial neural networks. Here, phosphorus-doped nanogranular SiO2 electrolyte is used as gate dielectric for protonic/electronic hybrid indium gallium zinc oxide (IGZO) synaptic transistor. In such synaptic transistors, protons within the SiO2 electrolyte are deemed as neurotransmitters of biological synapses. Paired-pulse facilitation (PPF) behaviors for the analogous information were mimicked. The temperature dependent PPF behaviors were also investigated systematically. The results indicate that the protonic/electronic hybrid IGZO synaptic transistors would be promising candidates for inorganic synapses in artificial neural network applications

  9. Dry Etching Characteristics of Amorphous Indium-Gallium-Zinc-Oxide Thin Films

    Institute of Scientific and Technical Information of China (English)

    郑艳彬; 李光; 王文龙; 李秀昌; 姜志刚

    2012-01-01

    Amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistor (TFT) backplane technology is the best candidate for flat panel displays (FPDs). In this paper, a-IGZO TFT structures are described. The effects of etch parameters (rf power, dc-bias voltage and gas pressure) on the etch rate and etch profile are discussed. Three kinds of gas mixtures are compared in the dry etching process of a-IGZO thin films. Lastly, three problems are pointed out that need to be addressed in the dry etching process of a-IGZO TFTs.

  10. Paired-pulse facilitation achieved in protonic/electronic hybrid indium gallium zinc oxide synaptic transistors

    Directory of Open Access Journals (Sweden)

    Li Qiang Guo

    2015-08-01

    Full Text Available Neuromorphic devices with paired pulse facilitation emulating that of biological synapses are the key to develop artificial neural networks. Here, phosphorus-doped nanogranular SiO2 electrolyte is used as gate dielectric for protonic/electronic hybrid indium gallium zinc oxide (IGZO synaptic transistor. In such synaptic transistors, protons within the SiO2 electrolyte are deemed as neurotransmitters of biological synapses. Paired-pulse facilitation (PPF behaviors for the analogous information were mimicked. The temperature dependent PPF behaviors were also investigated systematically. The results indicate that the protonic/electronic hybrid IGZO synaptic transistors would be promising candidates for inorganic synapses in artificial neural network applications.

  11. Optical and Micro-Structural Characterization of MBE Grown Indium Gallium Nitride Polar Quantum Dots

    KAUST Repository

    El Afandy, Rami

    2011-07-07

    Gallium nitride and related materials have ushered in scientific and technological breakthrough for lighting, mass data storage and high power electronic applications. These III-nitride materials have found their niche in blue light emitting diodes and blue laser diodes. Despite the current development, there are still technological problems that still impede the performance of such devices. Three-dimensional nanostructures are proposed to improve the electrical and thermal properties of III-nitride optical devices. This thesis consolidates the characterization results and unveils the unique physical properties of polar indium gallium nitride quantum dots grown by molecular beam epitaxy technique. In this thesis, a theoretical overview of the physical, structural and optical properties of polar III-nitrides quantum dots will be presented. Particular emphasis will be given to properties that distinguish truncated-pyramidal III-nitride quantum dots from other III-V semiconductor based quantum dots. The optical properties of indium gallium nitride quantum dots are mainly dominated by large polarization fields, as well as quantum confinement effects. Hence, the experimental investigations for such quantum dots require performing bandgap calculations taking into account the internal strain fields, polarization fields and confinement effects. The experiments conducted in this investigation involved the transmission electron microscopy and x-ray diffraction as well as photoluminescence spectroscopy. The analysis of the temperature dependence and excitation power dependence of the PL spectra sheds light on the carrier dynamics within the quantum dots, and its underlying wetting layer. A further analysis shows that indium gallium nitride quantum dots through three-dimensional confinements are able to prevent the electronic carriers from getting thermalized into defects which grants III-nitrides quantum dot based light emitting diodes superior thermally induced optical

  12. Interface Study on Amorphous Indium Gallium Zinc Oxide Thin Film Transistors Using High-k Gate Dielectric Materials

    OpenAIRE

    Yu-Hsien Lin; Jay-Chi Chou

    2015-01-01

    We investigated amorphous indium gallium zinc oxide (a-IGZO) thin film transistors (TFTs) using different high-k gate dielectric materials such as silicon nitride (Si3N4) and aluminum oxide (Al2O3) at low temperature process (

  13. The comparison between gallium arsenide and indium gallium arsenide as materials for solar cell performance using Silvaco application

    Energy Technology Data Exchange (ETDEWEB)

    Zahari, Suhaila Mohd; Norizan, Mohd Natashah; Mohamad, Ili Salwani; Osman, Rozana Aina Maulat; Taking, Sanna [School of Microelectronic Engineering, Universiti Malaysia Perlis, Kampus Pauh Putra, 02600 Arau, Perlis (Malaysia)

    2015-05-15

    The work presented in this paper is about the development of single and multilayer solar cells using GaAs and InGaAs in AM1.5 condition. The study includes the modeling structure and simulation of the device using Silvaco applications. The performance in term of efficiency of Indium Gallium Arsenide (InGaAs) and GaAs material was studied by modification of the doping concentration and thickness of material in solar cells. The efficiency of the GaAs solar cell was higher than InGaAs solar cell for single layer solar cell. Single layer GaAs achieved an efficiency about 25% compared to InGaAs which is only 2.65% of efficiency. For multilayer which includes both GaAs and InGaAs, the output power, P{sub max} was 8.91nW/cm² with the efficiency only 8.51%. GaAs is one of the best materials to be used in solar cell as a based compared to InGaAs.

  14. Ohmic contact formation process on low n-type gallium arsenide (GaAs) using indium gallium zinc oxide (IGZO)

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Seong-Uk [Samsung-SKKU Graphene Center and School of Electronics and Electrical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Product and Test Engineering Team, System LSI Division, Samsung Electronics Co., Ltd, Yongin 446-711 (Korea, Republic of); Jung, Woo-Shik [Department of Electrical Engineering, Stanford University, Stanford, CA 94305 (United States); Lee, In-Yeal; Jung, Hyun-Wook; Kim, Gil-Ho [Samsung-SKKU Graphene Center and School of Electronics and Electrical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Park, Jin-Hong, E-mail: jhpark9@skku.edu [Samsung-SKKU Graphene Center and School of Electronics and Electrical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2014-02-01

    Highlights: • We propose a method to fabricate non-gold Ohmic contact on low n-type GaAs with IGZO. • 0.15 A/cm{sup 2} on-current and 1.5 on/off-current ratio are achieved in the junction. • InAs and InGaAs formed by this process decrease an electron barrier height. • Traps generated by diffused O atoms also induce a trap-assisted tunneling phenomenon. - Abstract: Here, an excellent non-gold Ohmic contact on low n-type GaAs is demonstrated by using indium gallium zinc oxide and investigating through time of flight-secondary ion mass spectrometry, X-ray photoelectron spectroscopy, transmission electron microscopy, J–V measurement, and H [enthalpy], S [entropy], Cp [heat capacity] chemistry simulation. In is diffused through GaAs during annealing and reacts with As, forming InAs and InGaAs phases with lower energy bandgap. As a result, it decreases the electron barrier height, eventually increasing the reverse current. In addition, traps generated by diffused O atoms induce a trap-assisted tunneling phenomenon, increasing generation current and subsequently the reverse current. Therefore, an excellent Ohmic contact with 0.15 A/cm{sup 2} on-current density and 1.5 on/off-current ratio is achieved on n-type GaAs.

  15. Ohmic contact formation process on low n-type gallium arsenide (GaAs) using indium gallium zinc oxide (IGZO)

    International Nuclear Information System (INIS)

    Highlights: • We propose a method to fabricate non-gold Ohmic contact on low n-type GaAs with IGZO. • 0.15 A/cm2 on-current and 1.5 on/off-current ratio are achieved in the junction. • InAs and InGaAs formed by this process decrease an electron barrier height. • Traps generated by diffused O atoms also induce a trap-assisted tunneling phenomenon. - Abstract: Here, an excellent non-gold Ohmic contact on low n-type GaAs is demonstrated by using indium gallium zinc oxide and investigating through time of flight-secondary ion mass spectrometry, X-ray photoelectron spectroscopy, transmission electron microscopy, J–V measurement, and H [enthalpy], S [entropy], Cp [heat capacity] chemistry simulation. In is diffused through GaAs during annealing and reacts with As, forming InAs and InGaAs phases with lower energy bandgap. As a result, it decreases the electron barrier height, eventually increasing the reverse current. In addition, traps generated by diffused O atoms induce a trap-assisted tunneling phenomenon, increasing generation current and subsequently the reverse current. Therefore, an excellent Ohmic contact with 0.15 A/cm2 on-current density and 1.5 on/off-current ratio is achieved on n-type GaAs

  16. Indium-doped aluminium oxide as a non-radioactive test aerosol for aerosol experiments

    International Nuclear Information System (INIS)

    For testing inhalation facilities it is advantageous to use a non-radioactive, low toxicity test aerosol which can be detected at low concentrations. These criteria are met by a mechanically generated aerosol of indium-doped alumina. Although some cases of lung fibroses have been associated with the inhalation of aluminium compounds in industry, aluminum oxide aerosols are generally considered to be non-toxic. Indium was chosen as a dopant material because (a) it is not normally present in the lung in detectable amounts, (b) it is chemically similar to aluminum and (c) it can be detected in trace amounts by neutron activation analysis (Friberg et al., 1979). Indium aerosols have the same advantages as radioactive tracers for ease of detection, but they are non-toxic during use. This combination of properties offers advantages that could be of use in a wider range of applications than hitherto used, e.g. in inhalation experiments. This paper describes nose-only inhalation experiments on rats using an aerosol of alumina doped with indium. (author)

  17. Molybdenum Disulfide as a Protection Layer and Catalyst for Gallium Indium Phosphide Solar Water Splitting Photocathodes

    Energy Technology Data Exchange (ETDEWEB)

    Britto, Reuben J.; Benck, Jesse D.; Young, James L.; Hahn, Christopher; Deutsch, Todd G.; Jaramillo, Thomas F.

    2016-06-02

    Gallium indium phosphide (GaInP2) is a semiconductor with promising optical and electronic properties for solar water splitting, but its surface stability is problematic as it undergoes significant chemical and electrochemical corrosion in aqueous electrolytes. Molybdenum disulfide (MoS2) nanomaterials are promising to both protect GaInP2 and to improve catalysis since MoS2 is resistant to corrosion and also possesses high activity for the hydrogen evolution reaction (HER). In this work, we demonstrate that GaInP2 photocathodes coated with thin MoS2 surface protecting layers exhibit excellent activity and stability for solar hydrogen production, with no loss in performance (photocurrent onset potential, fill factor, and light limited current density) after 60 hours of operation. This represents a five-hundred fold increase in stability compared to bare p-GaInP2 samples tested in identical conditions.

  18. Study of breakdown voltage of indium-gallium-zinc-oxide-based Schottky diode

    Energy Technology Data Exchange (ETDEWEB)

    Xin, Qian; Yan, Linlong; Luo, Yi [School of Physics, Shandong University, Jinan 250100 (China); Song, Aimin, E-mail: A.Song@manchester.ac.uk [School of Physics, Shandong University, Jinan 250100 (China); School of Electrical and Electronic Engineering, University of Manchester, Manchester M13 9PL (United Kingdom)

    2015-03-16

    In contrast to the intensive studies on thin-film transistors based on indium gallium zinc oxide (IGZO), the research on IGZO-based diodes is still very limited, particularly on their behavior and stability under high bias voltages. Our experiments reveal a sensitive dependence of the breakdown voltage of IGZO Schottky diodes on the anode metal and the IGZO film thickness. Devices with an Au anode are found to breakdown easily at a reverse bias as low as −2.5 V, while the devices with a Pd anode and a 200-nm, fully depleted IGZO layer have survived up to −15 V. All diodes are fabricated by radio-frequency magnetron sputtering at room temperature without any thermal treatment, yet showing an ideality factor as low as 1.14, showing the possibility of achieving high-performance Schottky diodes on flexible plastic substrate.

  19. Interface location-controlled indium gallium zinc oxide thin-film transistors using a solution process

    Science.gov (United States)

    Na, Jae Won; Kim, Yeong-gyu; Jung, Tae Soo; Tak, Young Jun; Park, Sung Pyo; Park, Jeong Woo; Kim, Si Joon; Kim, Hyun Jae

    2016-03-01

    The role of an interface as an electron-trapping layer in double-stacked indium gallium zinc oxide (IGZO) thin-film transistors (TFTs) was investigated and interface location-controlled (ILC) IGZO TFTs were introduced. In the ILC TFTs, the thickness of the top and bottom IGZO layers is controlled to change the location of the interface layer. The system exhibited improved electrical characteristics as the location of the interface layer moved further from the gate insulator: field-effect mobility increased from 0.36 to 2.17 cm2 V-1 s-1, and the on-current increased from 2.43  ×  10-5 to 1.33  ×  10-4 A. The enhanced electrical characteristics are attributed to the absence of an electron-trapping interface layer in the effective channel layer where electrons are accumulated under positive gate bias voltage.

  20. Optical Spectroscopy of Indium Gallium Arsenide/gallium Arsenide Quantum Wells

    Science.gov (United States)

    Adams, Stephen J. A.

    1992-01-01

    Available from UMI in association with The British Library. In_{rm x}Ga _{rm 1-x}As/GaAs quantum wells have been studied using optical and magneto -optical techniques. Photoluminescence (PL) and photoluminescence excitation (PLE) spectroscopy have been used to determine the valence band offset in these heterostructures which was found to vary between 0.4 for wells with indium concentration x = 0.08 to 0.2 for wells with x = 0.21. An interband magneto-luminescence oscillation (IMLO) technique has been applied to the study of undoped 'multi-single' quantum well samples and the theoretically predicted peaked nature of the exciton binding energy as a function of well width has been observed for the first time in any material system. The conduction band effective mass was also determined in the same samples using Optically Detected Cyclotron Resonance (ODCR) and found to be constant over the range of well widths studied at a value close to that of the bulk, with a suitable correction for strain effects. This result was then combined with the IMLO data, fitted to the theory of Akimoto and Hasegawa, to deduce the hole mass as a function of well width, which was found to increase significantly in narrower wells. PL and PLE data was also obtained from modulation doped quantum wells. The PL involving transitions from highly populated subbands was found to be much broader than the PLE data from unpopulated subbands, where the transitions were strongly excitonic. Furthermore the PL linewidth in n-type samples was somewhat greater than that in p-type samples because of the difference in particle effective mass. Comparison of the Fermi energy deduced from PL in n-type samples with Hall and Shubnikov-de Haas measurements suggested an enhancement in the density-of -states over the value in undoped wells. Interesting effects were also observed in the quantum well luminescence arising from an interaction with GaAs deep levels in the barrier layers. A novel method was used to

  1. Effect of microtextured surface topography on the wetting behavior of eutectic gallium-indium alloys.

    Science.gov (United States)

    Kramer, Rebecca K; Boley, J William; Stone, Howard A; Weaver, James C; Wood, Robert J

    2014-01-21

    Liquid-embedded elastomer electronics have recently attracted much attention as key elements of highly deformable and "soft" electromechanical systems. Many of these fluid-elastomer composites utilize liquid metal alloys because of their high conductivities and inherent compliance. Understanding how these alloys interface with surfaces of various composition and texture is critical to the development of parallel processing technology, which is needed to create more complex and low-cost systems. In this work, we explore the wetting behaviors between droplets of gallium-indium alloys and thin metal films, with an emphasis on tin and indium substrates. We find that metallic droplets reactively wet thin metal foils, but the wettability of the foils may be tuned by the surface texture (produced by sputtering). The effects of both composition and texture of the substrate on wetting dynamics are quantified by measuring contact angle and droplet contact diameter as a function of time. Finally, we apply the Cassie-Baxter model to the sputtered and native substrates to gain insight into the behavior of liquid metals and the role of the oxide formation during interfacial processes. PMID:24358994

  2. Correlation of acid-base properties of polymeric chelate sorbents and pH50 of gallium and indium sorption

    International Nuclear Information System (INIS)

    Complexing properties of synthesized polymeric chelate-forming sorbents - substituents of polystyrene-azo-pyrocatechol - are investigated and quantitative correlations between pKOH of functional analytical group and pH50 of chelate formation are determined to investigate regularities of interactions in element - sorbent system. Correlations obtained make it possible to realize special forecast on choice and usage of chelate sorbents for separation and concentrating of gallium and indium microquantities from objects of different nature

  3. Transport of Indium, Gallium and Thallium Metal Ions Through Chromatographic Fiber Supported Solid Membrane in Acetylacetone Containing Mixed Solvents

    Institute of Scientific and Technical Information of China (English)

    Abaji Gaikwad

    2011-01-01

    The transport of metal ions of indium, gallium and thallium from source solution to receiving phase through the chromatographic fiber supported solid membrane in the acetylacetone (HAA) containing mixed solvent system has been explored. The fibers supported solid membranes were prepared with chemical synthesis from cellulose fibers and citric acid with the carboxylic acid ion exchange groups introduced. The experimental variables, such as concentration of metal ions (10^-2 to 10^-4 mol.L^-1) in the source solution, mixed solvent composition [for exampl, e, acetylacetone, (2,4-pentanedione), (HAA) 20% (by volume), 1,4-dioxane 10% to 60% and HC1 0.25 to 2 mol.L^-1] in the receiving phase and stirring speed (50-130 r.min ) of the bulk source and receiving phase, were explored. The efficiency of mixed solvents for the transport of metal ions from the source to receiving phase through the fiber supported solid membrane was evaluated. The combined ion exchange solvent extraction (CIESE) was observed effective for the selective transport of thallium, indium and gallium metal ions through fiber supported solid membrane in mixed solvents. The oxonium salt formation in the receiving phase enhances thallium, indium and gallium metal ion transport through solid membrane phase. The selective transport of thallium metal ions from source phase was observed from indium and gallium metal ions in the presence of hydrochloric acid in organic solvents in receiving phase. The separation of thallium metal ions from the binary mixtures of Be(II), Ti(IV), AI(III) Ca(II), Mg(II), K (I), La(III) and Y(III) was carried out in the mixed solvent system using cellulose fiber supported solid membrane.

  4. Indium gallium arsenide imaging with smaller cameras, higher-resolution arrays, and greater material sensitivity

    Science.gov (United States)

    Ettenberg, Martin H.; Cohen, Marshall J.; Brubaker, Robert M.; Lange, Michael J.; O'Grady, Matthew T.; Olsen, Gregory H.

    2002-08-01

    Indium Gallium Arsenide (InGaAs) photodiode arrays have numerous commercial, industrial, and military applications. During the past 10 years, great strides have been made in the development of these devices starting with simple 256-element linear photodiode arrays and progressing to the large 640 x 512 element area arrays now readily available. Linear arrays are offered with 512 elements on a 25 micron pitch with no defective pixels, and are used in spectroscopic monitors for wavelength division multiplexing (WDM) systems as well as in machine vision applications. A 320 x 240 solid-state array operates at room temperature, which allows development of a camera which is smaller than 25 cm3 in volume, weighs less than 100 g and uses less than 750 mW of power. Two dimensional focal plane arrays and cameras have been manufactured with detectivity, D*, greater than 1014 cm-(root)Hz/W at room temperature and have demonstrated the ability to image at night. Cameras are also critical tools for the assembly and performance monitoring of optical switches and add-drop multiplexers in the telecommunications industry. These same cameras are used for the inspection of silicon wafers and fine art, laser beam profiling, and metals manufacturing. By varying the Indium content, InGaAs photodiode arrays can be tailored to cover the entire short-wave infrared spectrum from 1.0 micron to 2.5 microns. InGaAs focal plane arrays and cameras sensitive to 2.0 micron wavelength light are now available in 320 x 240 formats.

  5. Electronic transitions in the bandgap of copper indium gallium diselenide polycrystalline thin films

    Science.gov (United States)

    Heath, Jennifer Theresa

    The electronic properties of polycrystalline copper indium gallium diselenide thin films have been investigated, with emphasis on understanding the distribution and origin of electronic states in the bandgap. The samples studied were working photovoltaic devices with the structure ZnO/CdS/CuIn1-xGa xSe2/Mo, and photovoltaic efficiencies ranging from 8 to 16%. The CdS layer and the p-type CuIn1-xGa xSe2 film create the n+- p junction at the heart of these devices. The samples were investigated using four techniques based on the electrical response of the junction: admittance spectroscopy, drive level capacitance profiling, transient photocapacitance spectroscopy, and transient photocurrent spectroscopy. From these measurements the free carrier densities, defect densities within the bandgap, spatial uniformity, and minority carrier mobilities have been deduced. The sub-bandgap response from the CuIn1-xGaxSe2 film was dominated by two defects. One exhibited a thermal transition to the valence band with an activation energy ranging between 0.1 and 0.3 eV and thermal emission prefactors obeying the Meyer-Neldel rule. The second was detected as an optical transition 0.8 eV from the valence band edge. Neither of these defects exhibited densities that varied systematically with gallium content, implying that they are not directly connected with the group III elements in these alloys. The defect densities also do not clearly correlate with the photovoltaic device performance; however, the position of the 0.8 eV defect lies nearer to mid-gap in the higher gallium, and hence higher band gap, material. This implies that it may be a more important recombination center in these devices and may be partially responsible for the reduced photovoltaic efficiencies observed when Ga/(In + Ga) > 0.4. An additional defect response was observed near mid-gap in films grown by processes known to produce lower quality devices. The influence of defects located at grain boundaries was also

  6. Drain bias effect on the instability of amorphous indium gallium zinc oxide thin film transistor

    International Nuclear Information System (INIS)

    We fabricated amorphous indium gallium zinc oxide thin film transistors (TFTs) in a top gate structure on a glass substrate. We investigated the effect of drain bias on the instability of the device. Although the device showed highly stable characteristics under both positive and negative gate bias stress, it showed significant degradation in the transfer characteristics under drain bias stress. The degradation phenomena are somewhat similar to those of negative gate bias illumination stress (NBIS). In the case of NBIS, degradation mechanisms have been confused between two kinds of illustrations, one of which is hole trapping in the gate insulator and the other is an increase of electron density in the active layer. Our experimental results revealed that the degradation mechanism of drain bias stress is closer to the latter mechanism of NBIS in amorphous oxide TFTs. - Highlights: ► Drain bias also degrades amorphous oxide thin film transistors. ► Increase of electron density near the drain junction occurs under drain bias stress. ► Oxygen vacancies can be ionized through the impingement of fast electrons

  7. Amorphous indium-gallium-zinc-oxide as electron transport layer in organic photodetectors

    Energy Technology Data Exchange (ETDEWEB)

    Arora, H. [IMEC, Kapeldreef 75, 3001 Leuven (Belgium); Phelma–Grenoble INP, 3 Parvis Louis Néel, 38016 Grenoble Cedex 01 (France); Malinowski, P. E., E-mail: pawel.malinowski@imec.be; Chasin, A.; Cheyns, D.; Steudel, S.; Schols, S. [IMEC, Kapeldreef 75, 3001 Leuven (Belgium); Heremans, P. [IMEC, Kapeldreef 75, 3001 Leuven (Belgium); ESAT, Katholieke Universiteit Leuven, Kasteelpark Arenberg 10, B-3001 Leuven (Belgium)

    2015-04-06

    Amorphous indium-gallium-zinc-oxide (a-IGZO) is demonstrated as an electron transport layer (ETL) in a high-performance organic photodetector (OPD). Dark current in the range of 10 nA/cm{sup 2} at a bias voltage of −2 V and a high photoresponse in the visible spectrum were obtained in inverted OPDs with poly(3-hexylthiophene) and phenyl-C{sub 61}-butyric acid methyl ester active layer. The best results were obtained for the optimum a-IGZO thickness of 7.5 nm with specific detectivity of 3 × 10{sup 12} Jones at the wavelength of 550 nm. The performance of the best OPD devices using a-IGZO was shown to be comparable to state-of-the-art devices based on TiO{sub x} as ETL, with higher rectification achieved in reverse bias. Yield and reproducibility were also enhanced with a-IGZO, facilitating fabrication of large area OPDs. Furthermore, easier integration with IGZO-based readout backplanes can be envisioned, where the channel material can be used as photodiode buffer layer after additional treatment.

  8. Interface location-controlled indium gallium zinc oxide thin-film transistors using a solution process

    International Nuclear Information System (INIS)

    The role of an interface as an electron-trapping layer in double-stacked indium gallium zinc oxide (IGZO) thin-film transistors (TFTs) was investigated and interface location-controlled (ILC) IGZO TFTs were introduced. In the ILC TFTs, the thickness of the top and bottom IGZO layers is controlled to change the location of the interface layer. The system exhibited improved electrical characteristics as the location of the interface layer moved further from the gate insulator: field-effect mobility increased from 0.36 to 2.17 cm2 V−1 s−1, and the on-current increased from 2.43  ×  10−5 to 1.33  ×  10−4 A. The enhanced electrical characteristics are attributed to the absence of an electron-trapping interface layer in the effective channel layer where electrons are accumulated under positive gate bias voltage. (paper)

  9. Performance of Indium Gallium Zinc Oxide Thin-Film Transistors in Saline Solution

    Science.gov (United States)

    Gupta, S.; Lacour, S. P.

    2016-06-01

    Transistors are often envisioned as alternative transducing devices to microelectrodes to communicate with the nervous system. Independently of the selected technology, the transistors should have reliable performance when exposed to physiological conditions (37°C, 5% CO2). Here, we report on the reliable performance of parylene encapsulated indium gallium zinc oxide (IGZO) based thin-film transistors (TFTs) after prolonged exposure to phosphate buffer saline solution in an incubator. The encapsulated IGZO TFTs (W/L = 500 μm/20 μm) have an ON/OFF current ratio of 107 and field effect mobility of 8.05 ± 0.78 cm2/Vs. The transistors operate within 4 V; their threshold voltages and subthreshold slope are ~1.9 V and 200 mV/decade, respectively. After weeks immersed in saline solution and at 37°C, we did not observe any significant deterioration in the transistors' performance. The long-term stability of IGZO transistors at physiological conditions is a promising result in the direction of metal oxide bioelectronics.

  10. Water-soluble thin film transistors and circuits based on amorphous indium-gallium-zinc oxide.

    Science.gov (United States)

    Jin, Sung Hun; Kang, Seung-Kyun; Cho, In-Tak; Han, Sang Youn; Chung, Ha Uk; Lee, Dong Joon; Shin, Jongmin; Baek, Geun Woo; Kim, Tae-il; Lee, Jong-Ho; Rogers, John A

    2015-04-22

    This paper presents device designs, circuit demonstrations, and dissolution kinetics for amorphous indium-gallium-zinc oxide (a-IGZO) thin film transistors (TFTs) comprised completely of water-soluble materials, including SiNx, SiOx, molybdenum, and poly(vinyl alcohol) (PVA). Collections of these types of physically transient a-IGZO TFTs and 5-stage ring oscillators (ROs), constructed with them, show field effect mobilities (∼10 cm2/Vs), on/off ratios (∼2×10(6)), subthreshold slopes (∼220 mV/dec), Ohmic contact properties, and oscillation frequency of 5.67 kHz at supply voltages of 19 V, all comparable to otherwise similar devices constructed in conventional ways with standard, nontransient materials. Studies of dissolution kinetics for a-IGZO films in deionized water, bovine serum, and phosphate buffer saline solution provide data of relevance for the potential use of these materials and this technology in temporary biomedical implants. PMID:25805699

  11. Flexible indium-gallium-zinc-oxide Schottky diode operating beyond 2.45 GHz.

    Science.gov (United States)

    Zhang, Jiawei; Li, Yunpeng; Zhang, Binglei; Wang, Hanbin; Xin, Qian; Song, Aimin

    2015-01-01

    Mechanically flexible mobile phones have been long anticipated due to the rapid development of thin-film electronics in the last couple of decades. However, to date, no such phone has been developed, largely due to a lack of flexible electronic components that are fast enough for the required wireless communications, in particular the speed-demanding front-end rectifiers. Here Schottky diodes based on amorphous indium-gallium-zinc-oxide (IGZO) are fabricated on flexible plastic substrates. Using suitable radio-frequency mesa structures, a range of IGZO thicknesses and diode sizes have been studied. The results have revealed an unexpected dependence of the diode speed on the IGZO thickness. The findings enable the best optimized flexible diodes to reach 6.3 GHz at zero bias, which is beyond the critical benchmark speed of 2.45 GHz to satisfy the principal frequency bands of smart phones such as those for cellular communication, Bluetooth, Wi-Fi and global satellite positioning. PMID:26138510

  12. Evaluation of critical materials for five advanced design photovoltaic cells with an assessment of indium and gallium

    Energy Technology Data Exchange (ETDEWEB)

    Watts, R.L.; Gurwell, W.E.; Jamieson, W.M.; Long, L.W.; Pawlewicz, W.T.; Smith, S.A.; Teeter, R.R.

    1980-05-01

    The objective of this study is to identify potential material supply constraints due to the large-scale deployment of five advanced photovoltaic (PV) cell designs, and to suggest strategies to reduce the impacts of these production capacity limitations and potential future material shortages. This report presents the results of the screening of the five following advanced PV cell designs: polycrystalline silicon, amorphous silicon, cadmium sulfide/copper sulfide frontwall, polycrystalline gallium arsenide MIS, and advanced concentrator-500X. Each of these five cells is screened individually assuming that they first come online in 1991, and that 25 GWe of peak capacity is online by the year 2000. A second computer screening assumes that each cell first comes online in 1991 and that each cell has 5 GWe of peak capacity by the year 2000, so that the total online cpacity for the five cells is 25 GWe. Based on a review of the preliminary basline screening results, suggestions were made for varying such parameters as the layer thickness, cell production processes, etc. The resulting PV cell characterizations were then screened again by the CMAP computer code. Earlier DOE sponsored work on the assessment of critical materials in PV cells conclusively identtified indium and gallium as warranting further investigation as to their availability. Therefore, this report includes a discussion of the future availability of gallium and indium. (WHK)

  13. Comparison of composition and atomic structure of amorphous indium gallium zinc oxide thin film transistor before and after positive bias temperature stress by transmission electron microscopy

    International Nuclear Information System (INIS)

    In this paper high resolution transmission electron microscopy analysis is performed on indium gallium zinc oxide thin film transistors to determine the crystal structure of the material. The relative elemental concentrations of indium, gallium, zinc and oxygen were quantified and analyzed using energy dispersive spectroscopy before and after subjection to positive gate bias temperature stress at 80 °C. Notable changes in the concentration of oxygen in the device channel were observed along with a reduced concentration of the elements indium, gallium and zinc after electrical stressing. We speculate this relative reduction in metal concentration could be attributed to the outdiffusion of metal ions from the channel region into the surrounding thermal oxide and the increase in the oxygen concentration in the stressed device is related to electric field assisted adsorption of oxygen from the ambient. (paper)

  14. Measuring systolic ankle and toe pressure using the strain gauge technique--a comparison study between mercury and indium-gallium strain gauges

    DEFF Research Database (Denmark)

    Broholm, Rikke; Wiinberg, Niels; Simonsen, Lene

    2014-01-01

    devices was performed for both toe and ankle level. RESULTS: A total of 53 patients were included (36 male). Mean age was 69 (range, 45-92 years). Mean pressures at toe and ankle level with the mercury and the indium-gallium strain gauges were 77 (range, 0-180) mm Hg and 113 (range, 15-190) mm Hg......BACKGROUND: Measurement of the ankle and toe pressures are often performed using a plethysmograph, compression cuffs and a strain gauge. Usually, the strain gauge contains mercury but other alternatives exist. From 2014, the mercury-containing strain gauge will no longer be available...... ankle and toe pressures volunteered for the study. Ankle and toe pressures were measured twice with the mercury and the indium-gallium strain gauge in random order. Comparison of the correlation between the mean pressure using the mercury and the indium-gallium device and the difference between the two...

  15. Synthesis, Characterization, and Processing of Copper, Indium, and Gallium Dithiocarbamates for Energy Conversion Applications

    Science.gov (United States)

    Duraj, S. A.; Duffy, N. V.; Hepp, A. F.; Cowen, J. E.; Hoops, M. D.; Brothrs, S. M.; Baird, M. J.; Fanwick, P. E.; Harris, J. D.; Jin, M. H.-C.

    2009-01-01

    Ten dithiocarbamate complexes of indium(III) and gallium(III) have been prepared and characterized by elemental analysis, infrared spectra and melting point. Each complex was decomposed thermally and its decomposition products separated and identified with the combination of gas chromatography/mass spectrometry. Their potential utility as photovoltaic materials precursors was assessed. Bis(dibenzyldithiocarbamato)- and bis(diethyldithiocarbamato)copper(II), Cu(S2CN(CH2C6H5)2)2 and Cu(S2CN(C2H5)2)2 respectively, have also been examined for their suitability as precursors for copper sulfides for the fabrication of photovoltaic materials. Each complex was decomposed thermally and the products analyzed by GC/MS, TGA and FTIR. The dibenzyl derivative complex decomposed at a lower temperature (225-320 C) to yield CuS as the product. The diethyl derivative complex decomposed at a higher temperature (260-325 C) to yield Cu2S. No Cu containing fragments were noted in the mass spectra. Unusual recombination fragments were observed in the mass spectra of the diethyl derivative. Tris(bis(phenylmethyl)carbamodithioato-S,S'), commonly referred to as tris(N,N-dibenzyldithiocarbamato)indium(III), In(S2CNBz2)3, was synthesized and characterized by single crystal X-ray crystallography. The compound crystallizes in the triclinic space group P1(bar) with two molecules per unit cell. The material was further characterized using a novel analytical system employing the combined powers of thermogravimetric analysis, gas chromatography/mass spectrometry, and Fourier transform infrared (FT-IR) spectroscopy to investigate its potential use as a precursor for the chemical vapor deposition (CVD) of thin film materials for photovoltaic applications. Upon heating, the material thermally decomposes to release CS2 and benzyl moieties in to the gas phase, resulting in bulk In2S3. Preliminary spray CVD experiments indicate that In(S2CNBz2)3 decomposed on a Cu substrate reacts to produce

  16. Low-frequency noise properties in Pt-indium gallium zinc oxide Schottky diodes

    International Nuclear Information System (INIS)

    The low-frequency noise properties of Pt-indium gallium zinc oxide (IGZO) Schottky diodes at different forward biases are investigated. The IGZO layer and Pt contact were deposited by RF sputtering at room temperature. The diode showed an ideality factor of 1.2 and a barrier height of 0.94 eV. The current noise spectral density exhibited 1/f behavior at low frequencies. The analysis of the current dependency of the noise spectral density revealed that for the as-deposited diode, the noise followed Luo's mobility and diffusivity fluctuation model in the thermionic-emission-limited region and Hooge's empirical theory in the series-resistance-limited region. A low Hooge's constant of 1.4 × 10−9 was found in the space-charge region. In the series-resistance-limited region, the Hooge's constant was 2.2 × 10−5. After annealing, the diode showed degradation in the electrical performance. The interface-trap-induced noise dominated the noise spectrum. By using the random walk model, the interface-trap density was obtained to be 3.6 × 1015 eV−1 cm−2. This work provides a quantitative approach to analyze the properties of Pt-IGZO interfacial layers. These low noise properties are a prerequisite to the use of IGZO Schottky diodes in switch elements in memory devices, photosensors, and mixer diodes

  17. Nanoscale Synthesis of Two Porphyrin-Based MOFs with Gallium and Indium.

    Science.gov (United States)

    Rhauderwiek, Timo; Waitschat, Steve; Wuttke, Stefan; Reinsch, Helge; Bein, Thomas; Stock, Norbert

    2016-06-01

    Two porphyrin-based metal-organic frameworks (MOFs) containing gallium or indium, [Ga2(OH)2(H2TCPP)]·3DMF·3H2O (Ga-PMOF) and [In2(OH)2(H2TCPP)]·3DMF·4H2O (In-PMOF) (H6TCPP = 4-tetracarboxyphenylporphyrin), were discovered using high-throughput methods. The structure was refined by the Rietveld-method starting from the structure model of Al-PMOF, [Al2(OH)2(H2TCPP)]. The new PMOFs exhibit BET surface areas between 1150 and 1400 m(2) g(-1) and are also porous toward CO2 (Ga-PMOF, 15.2 wt %; In-PMOF, 12.9 wt %). They are thermally stable in air up to 330 °C, but show limited chemical stabilities toward acids and bases. In order to achieve size control, different synthesis routes were investigated, i.e., batch synthesis at different temperatures (yield: In-PMOF-bs-th 96%, Ga-PMOF-bs-th 87%), ultrasound-assisted synthesis (yield: In-PMOF-bs-us 85%), and continuous-flow synthesis (yield: Ga-PMOF-cf 71%). By using these different methods we could control the nucleation rate and the crystal size. The crystal sizes were found to vary about 60 to 160 nm and 70 to 130 nm for Ga- and In-PMOF, respectively, which was proven by dynamic light scattering (DLS), powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) measurements.

  18. Low-frequency noise properties in Pt-indium gallium zinc oxide Schottky diodes

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jiawei; Zhang, Linqing; Ma, Xiaochen; Wilson, Joshua [School of Electrical and Electronic Engineering, University of Manchester, Manchester M13 9PL (United Kingdom); Jin, Jidong [Department of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ (United Kingdom); Du, Lulu; Xin, Qian [School of Physics, Shandong University, Jinan 250100 (China); Song, Aimin, E-mail: A.Song@manchester.ac.uk [School of Electrical and Electronic Engineering, University of Manchester, Manchester M13 9PL (United Kingdom); School of Physics, Shandong University, Jinan 250100 (China)

    2015-08-31

    The low-frequency noise properties of Pt-indium gallium zinc oxide (IGZO) Schottky diodes at different forward biases are investigated. The IGZO layer and Pt contact were deposited by RF sputtering at room temperature. The diode showed an ideality factor of 1.2 and a barrier height of 0.94 eV. The current noise spectral density exhibited 1/f behavior at low frequencies. The analysis of the current dependency of the noise spectral density revealed that for the as-deposited diode, the noise followed Luo's mobility and diffusivity fluctuation model in the thermionic-emission-limited region and Hooge's empirical theory in the series-resistance-limited region. A low Hooge's constant of 1.4 × 10{sup −9} was found in the space-charge region. In the series-resistance-limited region, the Hooge's constant was 2.2 × 10{sup −5}. After annealing, the diode showed degradation in the electrical performance. The interface-trap-induced noise dominated the noise spectrum. By using the random walk model, the interface-trap density was obtained to be 3.6 × 10{sup 15 }eV{sup −1 }cm{sup −2}. This work provides a quantitative approach to analyze the properties of Pt-IGZO interfacial layers. These low noise properties are a prerequisite to the use of IGZO Schottky diodes in switch elements in memory devices, photosensors, and mixer diodes.

  19. Electromechanical properties of amorphous indium-gallium-zinc-oxide transistors structured with an island configuration on plastic

    Science.gov (United States)

    Park, Chang Bum; Na, Hyung Il; Yoo, Soon Sung; Park, Kwon-Shik

    2016-03-01

    A comparative study of the electromechanical properties was carried out on a low-temperature-processed amorphous indium-gallium-zinc-oxide thin-film transistor, particularly with regard to the structural design of the device under the stress accumulation of an outward bending surface. Shown herein is the reliable electromechanical integrity of island-structured devices against the mechanical strain at bending radii of mm order. The onset of crack strain also closely corresponded to the electrical failure of the stressed device. These results revealed that the island configuration on the bending surface effectively suppresses the stress accumulation on sheets composed of inorganic stacked layers in a uniaxial direction.

  20. Saddle-like deformation in a dielectric elastomer actuator embedded with liquid-phase gallium-indium electrodes

    Science.gov (United States)

    Wissman, J.; Finkenauer, L.; Deseri, L.; Majidi, C.

    2014-10-01

    We introduce a dielectric elastomer actuator (DEA) composed of liquid-phase Gallium-Indium (GaIn) alloy electrodes embedded between layers of poly(dimethylsiloxane) (PDMS) and examine its mechanics using a specialized elastic shell theory. Residual stresses in the dielectric and sealing layers of PDMS cause the DEA to deform into a saddle-like geometry (Gaussian curvature K PDMS composite. By accurately modeling electromechanical coupling in a soft-matter DEA, this theory can inform improvements in design and fabrication.

  1. Aluminium, gallium, and molybdenum toxicity to the tropical marine microalga Isochrysis galbana.

    Science.gov (United States)

    Trenfield, Melanie A; van Dam, Joost W; Harford, Andrew J; Parry, David; Streten, Claire; Gibb, Karen; van Dam, Rick A

    2015-08-01

    There is a shortage of established chronic toxicity test methods for assessing the toxicity of contaminants to tropical marine organisms. The authors tested the suitability of the tropical microalga Isochrysis galbana for use in routine ecotoxicology and assessed the effects of 72-h exposures to copper (Cu, a reference toxicant), aluminium (Al), gallium (Ga), and molybdenum (Mo), key metals of alumina refinery discharge, on the growth of I. galbana at 3 temperatures: 24 °C, 28 °C, and 31 °C. The sensitivity of both I. galbana and the test method was validated by the response to Cu exposure, with 10% and 50% effect concentrations (EC10 and EC50) of 2.5 μg/L and 18 μg/L, respectively. The EC10 and EC50 values for total Al at 28 °C were 640 μg/L and 3045 μg/L, respectively. The toxicity of both Cu and Al at 24 °C and 31 °C was similar to that at 28 °C. There was no measurable toxicity from dissolved Ga exposures of up to 6000 μg/L or exposures to dissolved Mo of up to 9500 μg/L. Solubility limits at 28 °C for the dissolved fractions (7000 μg/L Ga, and >6000 μg/L Mo. In test solutions containing >650 μg/L total Al, dissolved and precipitated forms of Al were present, with precipitated Al becoming more dominant as total Al increased. The test method proved suitable for routine ecotoxicology, with I. galbana showing sensitivity to Cu but Al, Ga, and Mo exhibiting little to no toxicity to this species.

  2. High stability mechanisms of quinary indium gallium zinc aluminum oxide multicomponent oxide films and thin film transistors

    International Nuclear Information System (INIS)

    Quinary indium gallium zinc aluminum oxide (IGZAO) multicomponent oxide films were deposited using indium gallium zinc oxide (IGZO) target and Al target by radio frequency magnetron cosputtering system. An extra carrier transport pathway could be provided by the 3 s orbitals of Al cations to improve the electrical properties of the IGZO films, and the oxygen instability could be stabilized by the strong Al-O bonds in the IGZAO films. The electron concentration change and the electron mobility change of the IGZAO films for aging time of 10 days under an air environment at 40 °C and 75% humidity were 20.1% and 2.4%, respectively. The experimental results verified the performance stability of the IGZAO films. Compared with the thin film transistors (TFTs) using conventional IGZO channel layer, in conducting the stability of TFTs with IGZAO channel layer, the transconductance gm change, threshold voltage VT change, and the subthreshold swing S value change under the same aging condition were improved to 7.9%, 10.5%, and 14.8%, respectively. Furthermore, the stable performances of the IGZAO TFTs were also verified by the positive gate bias stress. In this research, the quinary IGZAO multicomponent oxide films and that applied in TFTs were the first studied in the literature

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

    NARCIS (Netherlands)

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

    2014-01-01

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

  4. Eutectic Gallium-Indium (EGaIn) : A Liquid Metal Alloy for the Formation of Stable Structures in Microchannels at Room Temperature

    NARCIS (Netherlands)

    Dickey, Michael D.; Chiechi, Ryan C.; Larsen, Ryan J.; Weiss, Emily A.; Weitz, David A.; Whitesides, George M.

    2008-01-01

    This paper describes the rheological behavior of the liquid metal eutectic gallium-indium (EGaIn) as it is injected into microfluidic channels to form stable microstructures of liquid metal. EGaIn is well-suited for this application because of its rheological properties at room temperature: it behav

  5. Low-voltage gallium-indium-zinc-oxide thin film transistors based logic circuits on thin plastic foil: Building blocks for radio frequency identification application

    NARCIS (Netherlands)

    Tripathi, A.K.; Smits, E.C.P.; Putten, J.B.P.H. van der; Neer, M. van; Myny, K.; Nag, M.; Steudel, S.; Vicca, P.; O'Neill, K.; Veenendaal, E. van; Genoe, G.; Heremans, P.; Gelinck, G.H.

    2011-01-01

    In this work a technology to fabricate low-voltage amorphous gallium-indium-zinc oxide thin film transistors (TFTs) based integrated circuits on 25 µm foils is presented. High performance TFTs were fabricated at low processing temperatures (<150 °C) with field effect mobility around 17 cm2 /V s. The

  6. Electrical conduction processes in as-deposited indium phthalocyanine chloride thin films using gold and aluminium electrode combination

    Energy Technology Data Exchange (ETDEWEB)

    Samuel, Mammen; Menon, C S; Unnikrishnan, N V [School of Pure and Applied Physics, Mahatma Gandhi University, Kottayam-686 560, Kerala (India)

    2006-01-11

    Sandwich structures of the type (Au-InPcCl-Al) have been fabricated by successive vacuum deposition of indium phthalocyanine chloride (InPcCl) thin films and aluminium (Al) fingers onto Ohmic gold (Au) electrodes on glass substrates. Device characteristics of as-deposited Au/InPcCl/Al are obtained and found to show rectification properties. Current density-voltage characteristics under forward bias (aluminium electrode negative) are found to be due to Ohmic conduction at lower voltages. At higher voltages there is space charge limited conductivity (SCLC) controlled by an exponential trapping distribution above the valence edge. Transport properties of the material at ambient temperature have been obtained from the analysis of the samples in the Ohmic and SCLC regions. Under the reverse bias, Schottky emission is identified at lower voltages.

  7. Optical and micro-structural characterizations of MBE grown indium gallium nitride polar quantum dots

    KAUST Repository

    Elafandy, Rami T.

    2011-12-01

    Comparison between indium rich (27%) InGaN/GaN quantum dots (QDs) and their underlying wetting layer (WL) is performed by means of optical and structural characterizations. With increasing temperature, micro-photoluminescence (μPL) study reveals the superior ability of QDs to prevent carrier thermalization to nearby traps compared to the two dimensional WL. Thus, explaining the higher internal quantum efficiency of the QD nanostructure compared to the higher dimensional WL. Structural characterization (X-ray diffraction (XRD)) and transmission electron microscopy (TEM)) reveal an increase in the QD indium content over the WL indium content which is due to strain induced drifts. © 2011 IEEE.

  8. Improved characteristics of amorphous indium-gallium-zinc-oxide-based resistive random access memory using hydrogen post-annealing

    Science.gov (United States)

    Kang, Dae Yun; Lee, Tae-Ho; Kim, Tae Geun

    2016-08-01

    The authors report an improvement in resistive switching (RS) characteristics of amorphous indium-gallium-zinc-oxide (a-IGZO)-based resistive random access memory devices using hydrogen post-annealing. Because this a-IGZO thin film has oxygen off-stoichiometry in the form of deficient and excessive oxygen sites, the film properties can be improved by introducing hydrogen atoms through the annealing process. After hydrogen post-annealing, the device exhibited a stable bipolar RS, low-voltage set and reset operation, long retention (>105 s), good endurance (>106 cycles), and a narrow distribution in each current state. The effect of hydrogen post-annealing is also investigated by analyzing the sample surface using X-ray photon spectroscopy and atomic force microscopy.

  9. Printed indium gallium zinc oxide transistors. Self-assembled nanodielectric effects on low-temperature combustion growth and carrier mobility.

    Science.gov (United States)

    Everaerts, Ken; Zeng, Li; Hennek, Jonathan W; Camacho, Diana I; Jariwala, Deep; Bedzyk, Michael J; Hersam, Mark C; Marks, Tobin J

    2013-11-27

    Solution-processed amorphous oxide semiconductors (AOSs) are emerging as important electronic materials for displays and transparent electronics. We report here on the fabrication, microstructure, and performance characteristics of inkjet-printed, low-temperature combustion-processed, amorphous indium gallium zinc oxide (a-IGZO) thin-film transistors (TFTs) grown on solution-processed hafnia self-assembled nanodielectrics (Hf-SANDs). TFT performance for devices processed below 300 °C includes >4× enhancement in electron mobility (μFE) on Hf-SAND versus SiO2 or ALD-HfO2 gate dielectrics, while other metrics such as subthreshold swing (SS), current on:off ratio (ION:IOFF), threshold voltage (Vth), and gate leakage current (Ig) are unchanged or enhanced. Thus, low voltage IGZO/SAND TFT operation (nanodielectrics.

  10. High performance solution-deposited amorphous indium gallium zinc oxide thin film transistors by oxygen plasma treatment

    KAUST Repository

    Nayak, Pradipta K.

    2012-05-16

    Solution-deposited amorphous indium gallium zinc oxide (a-IGZO) thin film transistors(TFTs) with high performance were fabricated using O2-plasma treatment of the films prior to high temperature annealing. The O2-plasma treatment resulted in a decrease in oxygen vacancy and residual hydrocarbon concentration in the a-IGZO films, as well as an improvement in the dielectric/channel interfacial roughness. As a result, the TFTs with O2-plasma treated a-IGZO channel layers showed three times higher linear field-effect mobility compared to the untreated a-IGZO over a range of processing temperatures. The O2-plasma treatment effectively reduces the required processing temperature of solution-deposited a-IGZO films to achieve the required performance.

  11. Short-Term Synaptic Plasticity Regulation in Solution-Gated Indium-Gallium-Zinc-Oxide Electric-Double-Layer Transistors.

    Science.gov (United States)

    Wan, Chang Jin; Liu, Yang Hui; Zhu, Li Qiang; Feng, Ping; Shi, Yi; Wan, Qing

    2016-04-20

    In the biological nervous system, synaptic plasticity regulation is based on the modulation of ionic fluxes, and such regulation was regarded as the fundamental mechanism underlying memory and learning. Inspired by such biological strategies, indium-gallium-zinc-oxide (IGZO) electric-double-layer (EDL) transistors gated by aqueous solutions were proposed for synaptic behavior emulations. Short-term synaptic plasticity, such as paired-pulse facilitation, high-pass filtering, and orientation tuning, was experimentally emulated in these EDL transistors. Most importantly, we found that such short-term synaptic plasticity can be effectively regulated by alcohol (ethyl alcohol) and salt (potassium chloride) additives. Our results suggest that solution gated oxide-based EDL transistors could act as the platforms for short-term synaptic plasticity emulation. PMID:27007748

  12. Pillar Initiated Growth of High Indium Content Bulk Indium Gallium Nitride to Improve the Material Quality for Photonic Devices

    Science.gov (United States)

    McFelea, Heather Dale

    The goal of this research was to reduce dislocations and strain in high indium content bulk InGaN to improve quality for optical devices. In an attempt to achieve this goal, InGaN pillars were grown with compositions that matched the composition of the bulk InGaN grown on top. Pillar height and density were optimized to facilitate coalescence on top of the pillars. It was expected that dislocations within the pillars would bend to side facets, thereby reducing the dislocation density in the bulk overgrowth, however this was not observed. It was also expected that pillars would be completely relaxed at the interface with the substrate. It was shown that pillars are mostly relaxed, but not completely. Mechanisms are proposed to explain why threading dislocations did not bend and how complete relaxation may have been achieved by mechanisms outside of interfacial misfit dislocation formation. Phase separation was not observed by TEM but may be related to the limitations of the sample or measurements. High indium observed at facets and stacking faults could be related to the extra photoluminescence peaks measured. This research focused on the InGaN pillars and first stages of coalescence on top of the pillars, saving bulk growth and device optimization for future research.

  13. A transparent diode with high rectifying ratio using amorphous indium-gallium-zinc oxide/SiNx coupled junction

    International Nuclear Information System (INIS)

    We introduce a transparent diode that shows both high rectifying ratio and low leakage current at process temperature below 250 °C. This device is clearly distinguished from all previous transparent diodes in that the rectifying behavior results from the junction between a semiconductor (amorphous indium-gallium-zinc oxide (a-IGZO)) and insulator (SiNx). We systematically study the properties of each junction within the device structure and demonstrate that the a-IGZO/SiNx junction is the source of the outstanding rectification. The electrical characteristics of this transparent diode are: 2.8 A/cm2 on-current density measured at −7 V; lower than 7.3 × 10−9 A/cm2 off-current density; 2.53 ideality factor; and high rectifying ratio of 108–109. Furthermore, the diode structure has a transmittance of over 80% across the visible light range. The operating principle of the indium-tin oxide (ITO)/a-IGZO/SiNx/ITO device was examined with an aid of the energy band diagram and we propose a preliminary model for the rectifying behavior. Finally, we suggest further directions for research on this transparent diode

  14. Highly Thermostable, Non-oxidizable Indium, Gallium, and Aluminium Perfluorophthalocyanines with n-Type Character.

    Science.gov (United States)

    Łapok, Łukasz; Obłoza, Magdalena; Nowakowska, Maria

    2016-08-16

    Perfluorophthalocyanines incorporating three-valent metals, namely In(Cl), Ga(Cl), and Al(Cl), have been synthesized and characterized. Thermogravimetric analysis revealed that these compounds exhibit outstanding thermal stability and a tendency to sublime at a temperature exceeding around 350 °C without thermal decomposition. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were used to probe the frontier orbital energy levels of these compounds in THF solution. All three compounds undergo three quasi-reversible reductions with the first one leading to the formation of an anion radical, namely MPc(-.) , as confirmed by spectroelectrochemistry. The compounds studied were intrinsically resistive to oxidation, which indicates that they are very good electron acceptors (n-type materials). The HOMO-LUMO energy gaps (Eg ) of the three compounds determined by UV/Vis spectroscopy were relatively unaffected by the three-valent metals incorporated into the phthalocyanine macrocycle. Similarly, the energies of the HOMO (EHOMO ) and LUMO (ELUMO ) orbitals remained virtually unaffected by the three-valent metals in the perfluorophthalocyanine. Importantly, all the perfluorophthalocyanines studied possess LUMO levels between -4.76 and -4.85 eV, which makes their reduced forms resistant to electron trapping by O2 and H2 O. This property opens up the possibility for the fabrication of electronic devices operating under ambient conditions. All three compounds demonstrated very good photostability as solid thin films. PMID:27405880

  15. Nonstationary structure of atomic and molecular layers in electrothermal. Atomic absorption spectrometry: formation of atomic and molecular absorbing layers of gallium and indium

    International Nuclear Information System (INIS)

    The dynamics of the formation of absorbing layers of gallium and indium atoms and their compounds in a graphite tubular atomizer was investigated by the shadow spectral filming method. These compounds are localozed in the central part of the furnace over the platform and dissapear ay the hotter walls. It the case of gallium and indium atomization, the effects of chemical reactions between the vapor and the walls of the furnace on the formation of absorbing layers are stronger than that of diffusion and convective mass-transfer processes, which are common to all of the elements. Atom propagation from the center to the stomizer ends proceeds through the cascade mechanism because of its relatively low rate of warming up and strong longitudinal anisothermicity

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

    Science.gov (United States)

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

    2016-02-01

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

  17. Derived reference doses for three compounds used in the photovoltaics industry: Copper indium diselenide, copper gallium diselenide, and cadmium telluride

    Energy Technology Data Exchange (ETDEWEB)

    Moskowitz, P.D.; Bernholc, N.; DePhillips, M.P.; Viren, J.

    1995-07-06

    Polycrystalline thin-film photovoltaic modules made from copper indium diselenide (CIS), copper gallium diselenide (CGS), and cadmium telluride (CdTe) arc nearing commercial development. A wide range of issues are being examined as these materials move from the laboratory to large-scale production facilities to ensure their commercial success. Issues of traditional interest include module efficiency, stability and cost. More recently, there is increased focus given to environmental, health and safety issues surrounding the commercialization of these same devices. An examination of the toxicological properties of these materials, and their chemical parents is fundamental to this discussion. Chemicals that can present large hazards to human health or the environment are regulated often more strictly than those that are less hazardous. Stricter control over how these materials are handled and disposed can increase the costs associated with the production and use of these modules dramatically. Similarly, public perception can be strongly influenced by the inherent biological hazard that these materials possess. Thus, this report: presents a brief background tutorial on how toxicological data are developed and used; overviews the toxicological data available for CIS, CGS and CdTe; develops ``reference doses`` for each of these compounds; compares the reference doses for these compounds with those of their parents; discusses the implications of these findings to photovoltaics industry.

  18. Synthesis of Cu-Poor Copper-Indium-Gallium-Diselenide Nanoparticles by Solvothermal Route for Solar Cell Applications

    Directory of Open Access Journals (Sweden)

    Chung Ping Liu

    2014-01-01

    Full Text Available Copper-indium-gallium-diselenide (CIGS thin films were fabricated using precursor nanoparticle ink and sintering technology. The precursor was a Cu-poor quaternary compound with constituent ratios of Cu/(In+Ga=0.603, Ga/(In+Ga=0.674, and Se/(Cu+In+Ga=1.036. Cu-poor CIGS nanoparticles of chalcopyrite for solar cells were successfully synthesized using a relatively simple and convenient elemental solvothermal route. After a fixed reaction time of 36 h at 180°C, CIGS nanocrystals with diameters in the range of 20–70 nm were observed. The nanoparticle ink was fabricated by mixing CIGS nanoparticles, a solvent, and an organic polymer. Analytical results reveal that the Cu-poor CIGS absorption layer prepared from a nanoparticle-ink polymer by sintering has a chalcopyrite structure and a favorable composition. For this kind of sample, its mole ratio of Cu : In : Ga : Se is equal to 0.617 : 0.410 : 0.510 : 2.464 and related ratios of Ga/(In+Ga and Cu/(In+Ga are 0.554 and 0.671, respectively. Under the condition of standard air mass 1.5 global illumination, the conversion efficiency of the solar cell fabricated by this kind of sample is 4.05%.

  19. Impact of severe cracked germanium (111) substrate on aluminum indium gallium phosphate light-emitting-diode's electro-optical performance

    Science.gov (United States)

    Annaniah, Luruthudass; Devarajan, Mutharasu

    2016-07-01

    Cracked die is a serious failure mode in the Light Emitting Diode (LED) industry - affecting LED quality and long-term reliability performance. In this paper an investigation has been carried out to find the correlation between severe cracked germanium (Ge) substrate of an aluminum indium gallium phosphate (AlInGaP) LED and its electro-optical performance after the Temperature Cycle (TC) test. The LED dice were indented at several bond forces using a die bonder. The indented dice were analysed using a Scanning Electron Microscope (SEM). The result showed that severe cracks were observed at 180 gF onward. As the force of indentation increases, crack formation also becomes more severe thus resulting in the chipping of the substrate. The cracked dies were packaged and the TC test was performed. The results did not show any electro-optical failure or degradation, even after a 1000 cycle TC test. Several mechanically cross-sectioned cracked die LEDs, were analysed using SEM and found that no crack reached the active layer. This shows that severely cracked Ge substrate are able to withstand a -40°C/+100°C TC test up to 1000 cycles and LED optical performance is not affected. A small leakage current was observed in all of the cracked die LEDs in comparison to the reference unit. However, this value is smaller than the product specification and is of no concern.

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

    Science.gov (United States)

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

    2016-02-01

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

  1. Development of a unique laboratory standard: Indium gallium arsenide detector for the 500-1700 nm spectral region

    Science.gov (United States)

    1987-01-01

    A planar (5 mm diameter) indium gallium arsenide detector having a high (greater than 50 pct) quantum efficiency from the visible into the infrared spectrum (500 to 1700 nm) was fabricated. Quantum efficiencies as high as 37 pct at 510 nm, 58 pct at 820 nm and 62 pct at 1300 nm and 1550 nm were measured. A planar InP/InGaAs detector structure was also fabricated using vapor phase epitaxy to grow device structures with 0, 0.2, 0.4 and 0.6 micrometer thick InP caps. Quantum efficiency was studied as a function of cap thickness. Conventional detector structures were also used by completely etching off the InP cap after zinc diffusion. Calibrated quantum efficiencies were measured. Best results were obtained with devices whose caps were completely removed by etching. Certain problems still remain with these detectors including non-uniform shunt resistance, reproducibility, contact resistance and narrow band anti-reflection coatings.

  2. Semiconductor to metallic transition in bulk accumulated amorphous indium-gallium-zinc-oxide dual gate thin-film transistor

    International Nuclear Information System (INIS)

    We investigated the effects of top gate voltage (VTG) and temperature (in the range of 25 to 70 oC) on dual-gate (DG) back-channel-etched (BCE) amorphous-indium-gallium-zinc-oxide (a-IGZO) thin film transistors (TFTs) characteristics. The increment of VTG from -20V to +20V, decreases the threshold voltage (VTH) from 19.6V to 3.8V and increases the electron density to 8.8 x 1018cm−3. Temperature dependent field-effect mobility in saturation regime, extracted from bottom gate sweep, show a critical dependency on VTG. At VTG of 20V, the mobility decreases from 19.1 to 15.4 cm2/V ⋅ s with increasing temperature, showing a metallic conduction. On the other hand, at VTG of - 20V, the mobility increases from 6.4 to 7.5cm2/V ⋅ s with increasing temperature. Since the top gate bias controls the position of Fermi level, the temperature dependent mobility shows metallic conduction when the Fermi level is above the conduction band edge, by applying high positive bias to the top gate

  3. Channel length dependence of negative-bias-illumination-stress in amorphous-indium-gallium-zinc-oxide thin-film transistors

    International Nuclear Information System (INIS)

    We have investigated the dependence of Negative-Bias-illumination-Stress (NBIS) upon channel length, in amorphous-indium-gallium-zinc-oxide (a-IGZO) thin-film transistors (TFTs). The negative shift of the transfer characteristic associated with NBIS decreases for increasing channel length and is practically suppressed in devices with L = 100-μm. The effect is consistent with creation of donor defects, mainly in the channel regions adjacent to source and drain contacts. Excellent agreement with experiment has been obtained by an analytical treatment, approximating the distribution of donors in the active layer by a double exponential with characteristic length LD ∼ Ln ∼ 10-μm, the latter being the electron diffusion length. The model also shows that a device with a non-uniform doping distribution along the active layer is in all equivalent, at low drain voltages, to a device with the same doping averaged over the active layer length. These results highlight a new aspect of the NBIS mechanism, that is, the dependence of the effect upon the relative magnitude of photogenerated holes and electrons, which is controlled by the device potential/band profile. They may also provide the basis for device design solutions to minimize NBIS

  4. Contact resistance asymmetry of amorphous indium-gallium-zinc-oxide thin-film transistors by scanning Kelvin probe microscopy

    Science.gov (United States)

    Chen-Fei, Wu; Yun-Feng, Chen; Hai, Lu; Xiao-Ming, Huang; Fang-Fang, Ren; Dun-Jun, Chen; Rong, Zhang; You-Dou, Zheng

    2016-05-01

    In this work, a method based on scanning Kelvin probe microscopy is proposed to separately extract source/drain (S/D) series resistance in operating amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistors. The asymmetry behavior of S/D contact resistance is deduced and the underlying physics is discussed. The present results suggest that the asymmetry of S/D contact resistance is caused by the difference in bias conditions of the Schottky-like junction at the contact interface induced by the parasitic reaction between contact metal and a-IGZO. The overall contact resistance should be determined by both the bulk channel resistance of the contact region and the interface properties of the metal-semiconductor junction. Project supported by the Key Industrial R&D Program of Jiangsu Province, China (Grant No. BE2015155), the Priority Academic Program Development of Higher Education Institutions of Jiangsu Province, China, and the Fundamental Research Funds for the Central Universities, China (Grant No. 021014380033).

  5. Saddle-like deformation in a dielectric elastomer actuator embedded with liquid-phase gallium-indium electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Wissman, J., E-mail: jwissman@andrew.cmu.edu [Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Finkenauer, L. [Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Deseri, L. [DICAM, Department of Mechanical, Civil and Environmental Engineering, University of Trento, via Mesiano 77 38123 Trento (Italy); TMHRI-Department of Nanomedicine, The Methodist Hospital Research Institute, 6565 Fannin St., MS B-490 Houston, Texas 77030 (United States); Mechanics, Materials and Computing Center, CEE and ME-CIT, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Majidi, C. [Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Robotics Institute and Department of Civil and Environmental Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States)

    2014-10-14

    We introduce a dielectric elastomer actuator (DEA) composed of liquid-phase Gallium-Indium (GaIn) alloy electrodes embedded between layers of poly(dimethylsiloxane) (PDMS) and examine its mechanics using a specialized elastic shell theory. Residual stresses in the dielectric and sealing layers of PDMS cause the DEA to deform into a saddle-like geometry (Gaussian curvature K<0). Applying voltage Φ to the liquid metal electrodes induces electrostatic pressure (Maxwell stress) on the dielectric and relieves some of the residual stress. This reduces the longitudinal bending curvature and corresponding angle of deflection ϑ. Treating the elastomer as an incompressible, isotropic, NeoHookean solid, we develop a theory based on the principle of minimum potential energy to predict the principal curvatures as a function of Φ. Based on this theory, we predict a dependency of ϑ on Φ that is in strong agreement with experimental measurements performed on a GaIn-PDMS composite. By accurately modeling electromechanical coupling in a soft-matter DEA, this theory can inform improvements in design and fabrication.

  6. Activation of sputter-processed indium-gallium-zinc oxide films by simultaneous ultraviolet and thermal treatments

    Science.gov (United States)

    Tak, Young Jun; Du Ahn, Byung; Park, Sung Pyo; Kim, Si Joon; Song, Ae Ran; Chung, Kwun-Bum; Kim, Hyun Jae

    2016-02-01

    Indium-gallium-zinc oxide (IGZO) films, deposited by sputtering at room temperature, still require activation to achieve satisfactory semiconductor characteristics. Thermal treatment is typically carried out at temperatures above 300 °C. Here, we propose activating sputter- processed IGZO films using simultaneous ultraviolet and thermal (SUT) treatments to decrease the required temperature and enhance their electrical characteristics and stability. SUT treatment effectively decreased the amount of carbon residues and the number of defect sites related to oxygen vacancies and increased the number of metal oxide (M-O) bonds through the decomposition-rearrangement of M-O bonds and oxygen radicals. Activation of IGZO TFTs using the SUT treatment reduced the processing temperature to 150 °C and improved various electrical performance metrics including mobility, on-off ratio, and threshold voltage shift (positive bias stress for 10,000 s) from 3.23 to 15.81 cm2/Vs, 3.96 × 107 to 1.03 × 108, and 11.2 to 7.2 V, respectively.

  7. Semiconductor to metallic transition in bulk accumulated amorphous indium-gallium-zinc-oxide dual gate thin-film transistor

    Directory of Open Access Journals (Sweden)

    Minkyu Chun

    2015-05-01

    Full Text Available We investigated the effects of top gate voltage (VTG and temperature (in the range of 25 to 70 oC on dual-gate (DG back-channel-etched (BCE amorphous-indium-gallium-zinc-oxide (a-IGZO thin film transistors (TFTs characteristics. The increment of VTG from -20V to +20V, decreases the threshold voltage (VTH from 19.6V to 3.8V and increases the electron density to 8.8 x 1018cm−3. Temperature dependent field-effect mobility in saturation regime, extracted from bottom gate sweep, show a critical dependency on VTG. At VTG of 20V, the mobility decreases from 19.1 to 15.4 cm2/V ⋅ s with increasing temperature, showing a metallic conduction. On the other hand, at VTG of - 20V, the mobility increases from 6.4 to 7.5cm2/V ⋅ s with increasing temperature. Since the top gate bias controls the position of Fermi level, the temperature dependent mobility shows metallic conduction when the Fermi level is above the conduction band edge, by applying high positive bias to the top gate.

  8. Channel length dependence of negative-bias-illumination-stress in amorphous-indium-gallium-zinc-oxide thin-film transistors

    Energy Technology Data Exchange (ETDEWEB)

    Um, Jae Gwang; Mativenga, Mallory; Jang, Jin, E-mail: jjang@khu.ac.kr [Advanced Display Research Center, Department of Information Display, Kyung Hee University, Dongdaemun-gu, Seoul 130-701 (Korea, Republic of); Migliorato, Piero [Advanced Display Research Center, Department of Information Display, Kyung Hee University, Dongdaemun-gu, Seoul 130-701 (Korea, Republic of); Electrical Engineering Division, Department of Engineering, Cambridge University, Cambridge CB3 0FA (United Kingdom)

    2015-06-21

    We have investigated the dependence of Negative-Bias-illumination-Stress (NBIS) upon channel length, in amorphous-indium-gallium-zinc-oxide (a-IGZO) thin-film transistors (TFTs). The negative shift of the transfer characteristic associated with NBIS decreases for increasing channel length and is practically suppressed in devices with L = 100-μm. The effect is consistent with creation of donor defects, mainly in the channel regions adjacent to source and drain contacts. Excellent agreement with experiment has been obtained by an analytical treatment, approximating the distribution of donors in the active layer by a double exponential with characteristic length L{sub D} ∼ L{sub n} ∼ 10-μm, the latter being the electron diffusion length. The model also shows that a device with a non-uniform doping distribution along the active layer is in all equivalent, at low drain voltages, to a device with the same doping averaged over the active layer length. These results highlight a new aspect of the NBIS mechanism, that is, the dependence of the effect upon the relative magnitude of photogenerated holes and electrons, which is controlled by the device potential/band profile. They may also provide the basis for device design solutions to minimize NBIS.

  9. Semiconductor to metallic transition in bulk accumulated amorphous indium-gallium-zinc-oxide dual gate thin-film transistor

    Energy Technology Data Exchange (ETDEWEB)

    Chun, Minkyu; Chowdhury, Md Delwar Hossain; Jang, Jin, E-mail: jjang@khu.ac.kr [Advanced Display Research Center and Department of Information Display, Kyung Hee University, Seoul 130-701 (Korea, Republic of)

    2015-05-15

    We investigated the effects of top gate voltage (V{sub TG}) and temperature (in the range of 25 to 70 {sup o}C) on dual-gate (DG) back-channel-etched (BCE) amorphous-indium-gallium-zinc-oxide (a-IGZO) thin film transistors (TFTs) characteristics. The increment of V{sub TG} from -20V to +20V, decreases the threshold voltage (V{sub TH}) from 19.6V to 3.8V and increases the electron density to 8.8 x 10{sup 18}cm{sup −3}. Temperature dependent field-effect mobility in saturation regime, extracted from bottom gate sweep, show a critical dependency on V{sub TG}. At V{sub TG} of 20V, the mobility decreases from 19.1 to 15.4 cm{sup 2}/V ⋅ s with increasing temperature, showing a metallic conduction. On the other hand, at V{sub TG} of - 20V, the mobility increases from 6.4 to 7.5cm{sup 2}/V ⋅ s with increasing temperature. Since the top gate bias controls the position of Fermi level, the temperature dependent mobility shows metallic conduction when the Fermi level is above the conduction band edge, by applying high positive bias to the top gate.

  10. Interface Study on Amorphous Indium Gallium Zinc Oxide Thin Film Transistors Using High-k Gate Dielectric Materials

    Directory of Open Access Journals (Sweden)

    Yu-Hsien Lin

    2015-01-01

    Full Text Available We investigated amorphous indium gallium zinc oxide (a-IGZO thin film transistors (TFTs using different high-k gate dielectric materials such as silicon nitride (Si3N4 and aluminum oxide (Al2O3 at low temperature process (<300°C and compared them with low temperature silicon dioxide (SiO2. The IGZO device with high-k gate dielectric material will expect to get high gate capacitance density to induce large amount of channel carrier and generate the higher drive current. In addition, for the integrating process of integrating IGZO device, postannealing treatment is an essential process for completing the process. The chemical reaction of the high-k/IGZO interface due to heat formation in high-k/IGZO materials results in reliability issue. We also used the voltage stress for testing the reliability for the device with different high-k gate dielectric materials and explained the interface effect by charge band diagram.

  11. Crystallization behavior of amorphous indium-gallium-zinc-oxide films and its effects on thin-film transistor performance

    Science.gov (United States)

    Suko, Ayaka; Jia, JunJun; Nakamura, Shin-ichi; Kawashima, Emi; Utsuno, Futoshi; Yano, Koki; Shigesato, Yuzo

    2016-03-01

    Amorphous indium-gallium-zinc oxide (a-IGZO) films were deposited by DC magnetron sputtering and post-annealed in air at 300-1000 °C for 1 h to investigate the crystallization behavior in detail. X-ray diffraction, electron beam diffraction, and high-resolution electron microscopy revealed that the IGZO films showed an amorphous structure after post-annealing at 300 °C. At 600 °C, the films started to crystallize from the surface with c-axis preferred orientation. At 700-1000 °C, the films totally crystallized into polycrystalline structures, wherein the grains showed c-axis preferred orientation close to the surface and random orientation inside the films. The current-gate voltage (Id-Vg) characteristics of the IGZO thin-film transistor (TFT) showed that the threshold voltage (Vth) and subthreshold swing decreased markedly after the post-annealing at 300 °C. The TFT using the totally crystallized films also showed the decrease in Vth, whereas the field-effect mobility decreased considerably.

  12. High-Performance Inkjet-Printed Indium-Gallium-Zinc-Oxide Transistors Enabled by Embedded, Chemically Stable Graphene Electrodes.

    Science.gov (United States)

    Secor, Ethan B; Smith, Jeremy; Marks, Tobin J; Hersam, Mark C

    2016-07-13

    Recent developments in solution-processed amorphous oxide semiconductors have established indium-gallium-zinc-oxide (IGZO) as a promising candidate for printed electronics. A key challenge for this vision is the integration of IGZO thin-film transistor (TFT) channels with compatible source/drain electrodes using low-temperature, solution-phase patterning methods. Here we demonstrate the suitability of inkjet-printed graphene electrodes for this purpose. In contrast to common inkjet-printed silver-based conductive inks, graphene provides a chemically stable electrode-channel interface. Furthermore, by embedding the graphene electrode between two consecutive IGZO printing passes, high-performance IGZO TFTs are achieved with an electron mobility of ∼6 cm(2)/V·s and current on/off ratio of ∼10(5). The resulting printed devices exhibit robust stability to aging in ambient as well as excellent resilience to thermal stress, thereby offering a promising platform for future printed electronics applications. PMID:27327555

  13. Low-Temperature Photochemically Activated Amorphous Indium-Gallium-Zinc Oxide for Highly Stable Room-Temperature Gas Sensors.

    Science.gov (United States)

    Jaisutti, Rawat; Kim, Jaeyoung; Park, Sung Kyu; Kim, Yong-Hoon

    2016-08-10

    We report on highly stable amorphous indium-gallium-zinc oxide (IGZO) gas sensors for ultraviolet (UV)-activated room-temperature detection of volatile organic compounds (VOCs). The IGZO sensors fabricated by a low-temperature photochemical activation process and exhibiting two orders higher photocurrent compared to conventional zinc oxide sensors, allowed high gas sensitivity against various VOCs even at room temperature. From a systematic analysis, it was found that by increasing the UV intensity, the gas sensitivity, response time, and recovery behavior of an IGZO sensor were strongly enhanced. In particular, under an UV intensity of 30 mW cm(-2), the IGZO sensor exhibited gas sensitivity, response time and recovery time of 37%, 37 and 53 s, respectively, against 750 ppm concentration of acetone gas. Moreover, the IGZO gas sensor had an excellent long-term stability showing around 6% variation in gas sensitivity over 70 days. These results strongly support a conclusion that a low-temperature solution-processed amorphous IGZO film can serve as a good candidate for room-temperature VOCs sensors for emerging wearable electronics. PMID:27430635

  14. Comparison of indium-labeled-leukocyte imaging with sequential technetium-gallium scanning in the diagnosis of low-grade musculoskeletal sepsis. A prospective study

    International Nuclear Information System (INIS)

    We prospectively compared sequential technetium-gallium imaging with indium-labeled-leukocyte imaging in fifty patients with suspected low-grade musculoskeletal sepsis. Adequate images and follow-up examinations were obtained for forty-two patients. The presence or absence of low-grade sepsis was confirmed by histological and bacteriological examinations of tissue specimens taken at surgery in thirty of the forty-two patients. In these thirty patients, the sensitivity of sequential Tc-Ga imaging was 48 per cent, the specificity was 86 per cent, and the accuracy was 57 per cent, whereas the sensitivity of the indium-labeled-leukocyte technique was 83 per cent, the specificity was 86 per cent, and the accuracy was 83 per cent. When the additional twelve patients for whom surgery was deemed unnecessary were considered, the sensitivity of sequential Tc-Ga imaging was 50 per cent, the specificity was 78 per cent, and the accuracy was 62 per cent, as compared with a sensitivity of 83 per cent, a specificity of 94 per cent, and an accuracy of 88 per cent with the indium-labeled-leukocyte method. In patients with a prosthesis the indium-labeled-leukocyte image was 94 per cent accurate, compared with 75 per cent accuracy for sequential Tc-Ga imaging. Statistical analysis of these data demonstrated that the indium-labeled-leukocyte technique was superior to sequential Tc-Ga imaging in detecting areas of low-grade musculoskeletal sepsis

  15. Comparison of indium-labeled-leukocyte imaging with sequential technetium-gallium scanning in the diagnosis of low-grade musculoskeletal sepsis. A prospective study

    Energy Technology Data Exchange (ETDEWEB)

    Merkel, K.D.; Brown, M.L.; Dewanjee, M.K.; Fitzgerald, R.H. Jr.

    1985-03-01

    We prospectively compared sequential technetium-gallium imaging with indium-labeled-leukocyte imaging in fifty patients with suspected low-grade musculoskeletal sepsis. Adequate images and follow-up examinations were obtained for forty-two patients. The presence or absence of low-grade sepsis was confirmed by histological and bacteriological examinations of tissue specimens taken at surgery in thirty of the forty-two patients. In these thirty patients, the sensitivity of sequential Tc-Ga imaging was 48 per cent, the specificity was 86 per cent, and the accuracy was 57 per cent, whereas the sensitivity of the indium-labeled-leukocyte technique was 83 per cent, the specificity was 86 per cent, and the accuracy was 83 per cent. When the additional twelve patients for whom surgery was deemed unnecessary were considered, the sensitivity of sequential Tc-Ga imaging was 50 per cent, the specificity was 78 per cent, and the accuracy was 62 per cent, as compared with a sensitivity of 83 per cent, a specificity of 94 per cent, and an accuracy of 88 per cent with the indium-labeled-leukocyte method. In patients with a prosthesis the indium-labeled-leukocyte image was 94 per cent accurate, compared with 75 per cent accuracy for sequential Tc-Ga imaging. Statistical analysis of these data demonstrated that the indium-labeled-leukocyte technique was superior to sequential Tc-Ga imaging in detecting areas of low-grade musculoskeletal sepsis.

  16. Comparative study of highly dense aluminium- and gallium-doped zinc oxide transparent conducting sol–gel thin films

    Indian Academy of Sciences (India)

    Naji Al Dahoudi

    2014-10-01

    Transparent conducting aluminium- and gallium-doped zinc oxide (AZO and GZO) layers have been deposited by spin coating on glass substrates. The coatings have been sintered in air at 450 °C for 30 min and then post-annealed at 350 °C in a reducing atmosphere for 30 min. The electrical, optical and morphological properties of both coatings have been studied and compared. The conventional sols lead to very thin coating, typically 24 nm for a single layer of AZO and 32 nm of GZO with electrical resistivity of 0.72 and 0.35 cm, respectively. The value however, drastically decreases down to a minimum of 2.6 × 10-2 cm for AZO and 1.76 × 10-2 cm for GZO, when five multilayer coatings are made. The origin of these differences is due to the different morphology of the coatings showing different electron scattering process. The GZO sol leads to denser smoother structure (porosity of 5%) layers with an average roughness of 2.76 Å, while the AZO coating is formed by a more porous assembly (porosity of 20%) with an average roughness of 3.46 Å. Both coatings exhibit high transparency ( > 85%) in the visible spectrum range with a slight shift of the absorption energy gap.

  17. Comparison of the electronic structure of amorphous versus crystalline indium gallium zinc oxide semiconductor: structure, tail states and strain effects

    Science.gov (United States)

    de Jamblinne de Meux, A.; Pourtois, G.; Genoe, J.; Heremans, P.

    2015-11-01

    We study the evolution of the structural and electronic properties of crystalline indium gallium zinc oxide (IGZO) upon amorphization by first-principles calculation. The bottom of the conduction band (BCB) is found to be constituted of a pseudo-band of molecular orbitals that resonate at the same energy on different atomic sites. They display a bonding character between the s orbitals of the metal sites and an anti-bonding character arising from the interaction between the oxygen and metal s orbitals. The energy level of the BCB shifts upon breaking of the crystal symmetry during the amorphization process, which may be attributed to the reduction of the coordination of the cationic centers. The top of the valence band (TVB) is constructed from anti-bonding oxygen p orbitals. In the amorphous state, they have random orientation, in contrast to the crystalline state. This results in the appearance of localized tail states in the forbidden gap above the TVB. Zinc is found to play a predominant role in the generation of these tail states, while gallium hinders their formation. Last, we study the dependence of the fundamental gap and effective mass of IGZO on mechanical strain. The variation of the gap under strain arises from the enhancement of the anti-bonding interaction in the BCB due to the modification of the length of the oxygen-metal bonds and/or to a variation of the cation coordination. This effect is less pronounced for the amorphous material compared to the crystalline material, making amorphous IGZO a semiconductor of choice for flexible electronics. Finally, the effective mass is found to increase upon strain, in contrast to regular materials. This counterintuitive variation is due to the reduction of the electrostatic shielding of the cationic centers by oxygen, leading to an increase of the overlaps between the metal orbitals at the origin of the delocalization of the BCB. For the range of strain typically met in flexible electronics, the induced

  18. Comparison of the electrical and optical properties of direct current and radio frequency sputtered amorphous indium gallium zinc oxide films

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Jianke, E-mail: yaojk@pkusz.edu.cn [School of Computer and Information Engineering, Shenzhen Graduate School of Peking University, Shenzhen 518055 (China); Gong, Li [Instrumental Analysis and Research Center, Sun Yat-Sen University, Guangzhou 10275 (China); Xie, Lei [School of Computer and Information Engineering, Shenzhen Graduate School of Peking University, Shenzhen 518055 (China); Zhang, Shengdong, E-mail: zhangsd@pku.edu.cn [School of Computer and Information Engineering, Shenzhen Graduate School of Peking University, Shenzhen 518055 (China); Institute of Microelectronics, Peking University, Beijing 100871 (China)

    2013-01-01

    The electrical and optical properties of direct current and radio frequency (RF) sputtered amorphous indium gallium zinc oxide (a-IGZO) films are compared. It is found that the RF sputtered a-IGZO films have better stoichiometry (In:Ga:Zn:O = 1:1:1:2.5–3.0), lower electrical conductivity (σ < 8 S/cm), higher refractive index (n = 1.9–2.0) and larger band gap (E{sub g} = 3.02–3.29 eV), and show less shift of Fermi level (△ E{sub F} ∼ 0.26 eV) and increased concentration of electrons (△ N{sub e} ∼ 10{sup 4}) in the conduction band with the reduction concentration of oxygen vacancy (V{sub O}). Although a-IGZO has intensively been studied for a semiconductor channel material of thin film transistors in next-generation flat panel displays, its fundamental material parameters have not been thoroughly reported. In this work, the work function (φ) of a-IGZO films is tested with the ultraviolet photoelectron spectroscopy. It is found that the φ of a-IGZO films is in the range of 4.0–5.0 eV depending on the V{sub O}. - Highlights: ► Amorphous InGaZnO{sub 4} (a-IGZO) films were prepared with different sputtering modes. ► Electrical and optical properties of the different films were compared. ► Fermi level (△E{sub F}) shift in a-IGZO films were tested by X-ray photoelectron spectroscopy. ► The relation of △E{sub F} with the properties of a-IGZO films were discussed. ► Work function was tested by ultraviolet photoelectron spectroscopy.

  19. Comparison of the electrical and optical properties of direct current and radio frequency sputtered amorphous indium gallium zinc oxide films

    International Nuclear Information System (INIS)

    The electrical and optical properties of direct current and radio frequency (RF) sputtered amorphous indium gallium zinc oxide (a-IGZO) films are compared. It is found that the RF sputtered a-IGZO films have better stoichiometry (In:Ga:Zn:O = 1:1:1:2.5–3.0), lower electrical conductivity (σ < 8 S/cm), higher refractive index (n = 1.9–2.0) and larger band gap (Eg = 3.02–3.29 eV), and show less shift of Fermi level (△ EF ∼ 0.26 eV) and increased concentration of electrons (△ Ne ∼ 104) in the conduction band with the reduction concentration of oxygen vacancy (VO). Although a-IGZO has intensively been studied for a semiconductor channel material of thin film transistors in next-generation flat panel displays, its fundamental material parameters have not been thoroughly reported. In this work, the work function (φ) of a-IGZO films is tested with the ultraviolet photoelectron spectroscopy. It is found that the φ of a-IGZO films is in the range of 4.0–5.0 eV depending on the VO. - Highlights: ► Amorphous InGaZnO4 (a-IGZO) films were prepared with different sputtering modes. ► Electrical and optical properties of the different films were compared. ► Fermi level (△EF) shift in a-IGZO films were tested by X-ray photoelectron spectroscopy. ► The relation of △EF with the properties of a-IGZO films were discussed. ► Work function was tested by ultraviolet photoelectron spectroscopy

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

    Science.gov (United States)

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

    2016-08-01

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

  1. Liquid gallium and the eutectic gallium indium (EGaIn) alloy: Dielectric functions from 1.24 to 3.1 eV by electrochemical reduction of surface oxides

    Science.gov (United States)

    Morales, Daniel; Stoute, Nicholas A.; Yu, Zhiyuan; Aspnes, David E.; Dickey, Michael D.

    2016-08-01

    Liquid metals based on gallium are promising materials for soft, stretchable, and shape reconfigurable electromagnetic devices. The behavior of these metals relates directly to the thicknesses of their surface oxide layers, which can be determined nondestructively by ellipsometry if their dielectric functions ɛ are known. This paper reports on the dielectric functions of liquid gallium and the eutectic gallium indium (EGaIn) alloy from 1.24 to 3.1 eV at room temperature, measured by spectroscopic ellipsometry. Overlayer-induced artifacts, a continuing problem in optical measurements of these highly reactive metals, are eliminated by applying an electrochemically reductive potential to the surface of the metal immersed in an electrolyte. This technique enables measurements at ambient conditions while avoiding the complications associated with removing overlayers in a vacuum environment. The dielectric responses of both metals are closely represented by the Drude model. The EGaIn data suggest that in the absence of an oxide the surface is In-enriched, consistent with the previous vacuum-based studies. Possible reasons for discrepancies with previous measurements are discussed.

  2. Arsenic (III, V), indium (III), and gallium (III) toxicity to zebrafish embryos using a high-throughput multi-endpoint in vivo developmental and behavioral assay.

    Science.gov (United States)

    Olivares, Christopher I; Field, Jim A; Simonich, Michael; Tanguay, Robert L; Sierra-Alvarez, Reyes

    2016-04-01

    Gallium arsenide (GaAs), indium gallium arsenide (InGaAs) and other III/V materials are finding increasing application in microelectronic components. The rising demand for III/V-based products is leading to increasing generation of effluents containing ionic species of gallium, indium, and arsenic. The ecotoxicological hazard potential of these streams is unknown. While the toxicology of arsenic is comprehensive, much less is known about the effects of In(III) and Ga(III). The embryonic zebrafish was evaluated for mortality, developmental abnormalities, and photomotor response (PMR) behavior changes associated with exposure to As(III), As(V), Ga(III), and In(III). The As(III) lowest observable effect level (LOEL) for mortality was 500 μM at 24 and 120 h post fertilization (hpf). As(V) exposure was associated with significant mortality at 63 μM. The Ga(III)-citrate LOEL was 113 μM at 24 and 120 hpf. There was no association of significant mortality over the tested range of In(III)-citrate (56-900 μM) or sodium citrate (213-3400 μM) exposures. Only As(V) resulted in significant developmental abnormalities with LOEL of 500 μM. Removal of the chorion prior to As(III) and As(V) exposure was associated with increased incidence of mortality and developmental abnormality suggesting that the chorion may normally attenuate mass uptake of these metals by the embryo. Finally, As(III), As(V), and In(III) caused PMR hypoactivity (49-69% of control PMR) at 900-1000 μM. Overall, our results represent the first characterization of multidimensional toxicity effects of III/V ions in zebrafish embryos helping to fill a significant knowledge gap, particularly in Ga(III) and In(III) toxicology. PMID:26824274

  3. Arsenic (III, V), indium (III), and gallium (III) toxicity to zebrafish embryos using a high-throughput multi-endpoint in vivo developmental and behavioral assay.

    Science.gov (United States)

    Olivares, Christopher I; Field, Jim A; Simonich, Michael; Tanguay, Robert L; Sierra-Alvarez, Reyes

    2016-04-01

    Gallium arsenide (GaAs), indium gallium arsenide (InGaAs) and other III/V materials are finding increasing application in microelectronic components. The rising demand for III/V-based products is leading to increasing generation of effluents containing ionic species of gallium, indium, and arsenic. The ecotoxicological hazard potential of these streams is unknown. While the toxicology of arsenic is comprehensive, much less is known about the effects of In(III) and Ga(III). The embryonic zebrafish was evaluated for mortality, developmental abnormalities, and photomotor response (PMR) behavior changes associated with exposure to As(III), As(V), Ga(III), and In(III). The As(III) lowest observable effect level (LOEL) for mortality was 500 μM at 24 and 120 h post fertilization (hpf). As(V) exposure was associated with significant mortality at 63 μM. The Ga(III)-citrate LOEL was 113 μM at 24 and 120 hpf. There was no association of significant mortality over the tested range of In(III)-citrate (56-900 μM) or sodium citrate (213-3400 μM) exposures. Only As(V) resulted in significant developmental abnormalities with LOEL of 500 μM. Removal of the chorion prior to As(III) and As(V) exposure was associated with increased incidence of mortality and developmental abnormality suggesting that the chorion may normally attenuate mass uptake of these metals by the embryo. Finally, As(III), As(V), and In(III) caused PMR hypoactivity (49-69% of control PMR) at 900-1000 μM. Overall, our results represent the first characterization of multidimensional toxicity effects of III/V ions in zebrafish embryos helping to fill a significant knowledge gap, particularly in Ga(III) and In(III) toxicology.

  4. A 6b 10MS/s current-steering DAC manufactured with amorphous Gallium-Indium-Zinc-Oxide TFTs achieving SFDR > 30dB up to 300kHz

    NARCIS (Netherlands)

    Raiteri, D.; Torricelli, F.; Myny, K.; Nag, M.; Putten, B. van der; Smits, E.; Steudel, S.; Tempelaars, K.; Tripathi, A.K.; Gelinck, G.H.; Roermund, A. van; Cantatore, E.

    2012-01-01

    Amorphous Gallium-Indium-Zinc-Oxide (GIZO or IGZO) has been recently proposed [1] as an interesting semiconductor for manufacturing TFTs because of its mobility (μ∼20cm 2/Vs), superior to other common materials for large-area electronics like organic semiconductors and a-Si (μ∼1cm 2/Vs). The amorpho

  5. Paraffin wax as a diluent for extraction and separation of trivalent gallium, indium, and thallium with 2,6-bis-(1′-phenyl-3′-methyl-5′- oxopyrazole-4′) pyridineacyl

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A method is proposed for the extraction and separation of trivalent gallium, indium and thallium from their corre-sponding aqueous solutions at 65°C with 2, 6-bis-(l'-phenyl-3'-methyl-5'-oxopyrazole-4') pyridineacyl (H2PMBPPor H2A)using molten paraffin wax as a diluent. The values of pH 1/2 for extraction of gallium, indium and thallium are 2.62, 4.32 and4.93, respectively. Gallium can be extracted by H2PMBPP at a lower acid medium. The effect of solvent and the composi-tion of the extracted species are reported. And the thermodynamic data of the extraction are also obtained.

  6. Hydrogen Production from Water by Photolysis, Sonolysis and Sonophotolysis with Solid Solutions of Rare Earth, Gallium and Indium Oxides as Heterogeneous Catalysts

    Directory of Open Access Journals (Sweden)

    Marta Penconi

    2015-07-01

    Full Text Available In this work, we present the hydrogen production by photolysis, sonolysis and sonophotolysis of water in the presence of newly synthesized solid solutions of rare earth, gallium and indium oxides playing as catalysts. From the experiments of photolysis, we found that the best photocatalyst is the solid solution Y0.8Ga0.2InO3 doped by sulphur atoms. In experiments of sonolysis, we optimized the rate of hydrogen production by changing the amount of water, adding ethanol and tuning the power of our piezoelectric transducer. Finally, we performed sonolysis and sonophotolysis experiments in the presence of S:Y0.8Ga0.2InO3 finding a promising synergistic effect of UV-visible electromagnetic waves and 38 kHz ultrasound waves in producing H2.

  7. A thermalization energy analysis of the threshold voltage shift in amorphous indium gallium zinc oxide thin film transistors under positive gate bias stress

    Science.gov (United States)

    Niang, K. M.; Barquinha, P. M. C.; Martins, R. F. P.; Cobb, B.; Powell, M. J.; Flewitt, A. J.

    2016-02-01

    Thin film transistors (TFTs) employing an amorphous indium gallium zinc oxide (a-IGZO) channel layer exhibit a positive shift in the threshold voltage under the application of positive gate bias stress (PBS). The time and temperature dependence of the threshold voltage shift was measured and analysed using the thermalization energy concept. The peak energy barrier to defect conversion is extracted to be 0.75 eV and the attempt-to-escape frequency is extracted to be 107 s-1. These values are in remarkable agreement with measurements in a-IGZO TFTs under negative gate bias illumination stress (NBIS) reported recently (Flewitt and Powell, J. Appl. Phys. 115, 134501 (2014)). This suggests that the same physical process is responsible for both PBS and NBIS, and supports the oxygen vacancy defect migration model that the authors have previously proposed.

  8. Effect of Al2O3 insulator thickness on the structural integrity of amorphous indium-gallium-zinc-oxide based thin film transistors.

    Science.gov (United States)

    Kim, Hak-Jun; Hwang, In-Ju; Kim, Youn-Jea

    2014-12-01

    The current transparent oxide semiconductors (TOSs) technology provides flexibility and high performance. In this study, multi-stack nano-layers of TOSs were designed for three-dimensional analysis of amorphous indium-gallium-zinc-oxide (a-IGZO) based thin film transistors (TFTs). In particular, the effects of torsional and compressive stresses on the nano-sized active layers such as the a-IGZO layer were investigated. Numerical simulations were carried out to investigate the structural integrity of a-IGZO based TFTs with three different thicknesses of the aluminum oxide (Al2O3) insulator (δ = 10, 20, and 30 nm), respectively, using a commercial code, COMSOL Multiphysics. The results are graphically depicted for operating conditions. PMID:25971080

  9. Scaling characteristics of depletion type, fully transparent amorphous indium-gallium-zinc-oxide thin-film transistors and inverters following Ar plasma treatment

    Science.gov (United States)

    Kim, Joonwoo; Jeong, Soon Moon; Jeong, Jaewook

    2015-11-01

    We fabricated depletion type, transparent amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistors (TFTs) and inverters with an Ar plasma treatment and analyzed their scaling characteristics with channel lengths ranging from 2 to 100 µm. The improvement of the field-effect mobility of a-IGZO TFTs is apparent only for short channel lengths. There is also an unexpected side effect of the Ar plasma treatment, which introduces back-channel interfacial states and induces a positive shift in the threshold voltage of a-IGZO TFTs. The resulting increase in the field-effect mobility and the positive shift in the threshold voltage of each TFT increase the differential gain up to 3 times and the positive shift in the transient point of the transparent inverters.

  10. A transparent diode with high rectifying ratio using amorphous indium-gallium-zinc oxide/SiN{sub x} coupled junction

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Myung-Jea; Kim, Myeong-Ho; Choi, Duck-Kyun, E-mail: duck@hanyang.ac.kr [Department of Materials Science and Engineering, Hanyang University, Seoul 133-791 (Korea, Republic of)

    2015-08-03

    We introduce a transparent diode that shows both high rectifying ratio and low leakage current at process temperature below 250 °C. This device is clearly distinguished from all previous transparent diodes in that the rectifying behavior results from the junction between a semiconductor (amorphous indium-gallium-zinc oxide (a-IGZO)) and insulator (SiN{sub x}). We systematically study the properties of each junction within the device structure and demonstrate that the a-IGZO/SiN{sub x} junction is the source of the outstanding rectification. The electrical characteristics of this transparent diode are: 2.8 A/cm{sup 2} on-current density measured at −7 V; lower than 7.3 × 10{sup −9} A/cm{sup 2} off-current density; 2.53 ideality factor; and high rectifying ratio of 10{sup 8}–10{sup 9}. Furthermore, the diode structure has a transmittance of over 80% across the visible light range. The operating principle of the indium-tin oxide (ITO)/a-IGZO/SiN{sub x}/ITO device was examined with an aid of the energy band diagram and we propose a preliminary model for the rectifying behavior. Finally, we suggest further directions for research on this transparent diode.

  11. Indium and gallium diffusion through zirconia in the TiN/ZrO{sub 2}/InGaAs stack

    Energy Technology Data Exchange (ETDEWEB)

    Ceballos-Sanchez, O. [CINVESTAV-Unidad Queretaro, Queretaro, Qro. 76230 (Mexico); Univ. Grenoble Alpes, F-38000 Grenoble, France and CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Martinez, E.; Guedj, C.; Veillerot, M. [Univ. Grenoble Alpes, F-38000 Grenoble, France and CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Herrera-Gomez, A. [CINVESTAV-Unidad Queretaro, Queretaro, Qro. 76230 (Mexico)

    2015-06-01

    Angle-resolved X-ray Photoelectron Spectroscopy (ARXPS) was applied to the TiN/ZrO{sub 2}/InGaAs stack to assess its thermal stability. Through a robust ARXPS analysis, it was possible to observe subtle effects such as the thermally induced diffusion of substrate atomic species (In and Ga) through the dielectric layer. The detailed characterization of the film structure allowed for assessing the depth profiles of the diffused atomic species by means of the scenarios-method. Since the quantification for the amount of diffused material was done at different temperatures, it was possible to obtain an approximate value of the activation energy for the diffusion of indium through zirconia. The result is very similar to the previously reported values for indium diffusion through alumina and through hafnia.

  12. Impact of severe cracked germanium (111 substrate on aluminum indium gallium phosphate light-emitting-diode’s electro-optical performance

    Directory of Open Access Journals (Sweden)

    Annaniah Luruthudass

    2016-07-01

    Full Text Available Cracked die is a serious failure mode in the Light Emitting Diode (LED industry – affecting LED quality and long-term reliability performance. In this paper an investigation has been carried out to find the correlation between severe cracked germanium (Ge substrate of an aluminum indium gallium phosphate (AlInGaP LED and its electro-optical performance after the Temperature Cycle (TC test. The LED dice were indented at several bond forces using a die bonder. The indented dice were analysed using a Scanning Electron Microscope (SEM. The result showed that severe cracks were observed at 180 gF onward. As the force of indentation increases, crack formation also becomes more severe thus resulting in the chipping of the substrate. The cracked dies were packaged and the TC test was performed. The results did not show any electro-optical failure or degradation, even after a 1000 cycle TC test. Several mechanically cross-sectioned cracked die LEDs, were analysed using SEM and found that no crack reached the active layer. This shows that severely cracked Ge substrate are able to withstand a −40°C/+100°C TC test up to 1000 cycles and LED optical performance is not affected. A small leakage current was observed in all of the cracked die LEDs in comparison to the reference unit. However, this value is smaller than the product specification and is of no concern.

  13. Improvement of bias-stability in amorphous-indium-gallium-zinc-oxide thin-film transistors by using solution-processed Y2O3 passivation

    International Nuclear Information System (INIS)

    We demonstrate back channel improvement of back-channel-etch amorphous-indium-gallium-zinc-oxide (a-IGZO) thin-film transistors by using solution-processed yttrium oxide (Y2O3) passivation. Two different solvents, which are acetonitrile (35%) + ethylene glycol (65%), solvent A and deionized water, solvent B are investigated for the spin-on process of the Y2O3 passivation—performed after patterning source/drain (S/D) Mo electrodes by a conventional HNO3-based wet-etch process. Both solvents yield devices with good performance but those passivated by using solvent B exhibit better light and bias stability. Presence of yttrium at the a-IGZO back interface, where it occupies metal vacancy sites, is confirmed by X-ray photoelectron spectroscopy. The passivation effect of yttrium is more significant when solvent A is used because of the existence of more metal vacancies, given that the alcohol (65% ethylene glycol) in solvent A may dissolve the metal oxide (a-IGZO) through the formation of alkoxides and water

  14. High-pressure Gas Activation for Amorphous Indium-Gallium-Zinc-Oxide Thin-Film Transistors at 100 °C

    Science.gov (United States)

    Kim, Won-Gi; Tak, Young Jun; Du Ahn, Byung; Jung, Tae Soo; Chung, Kwun-Bum; Kim, Hyun Jae

    2016-03-01

    We investigated the use of high-pressure gases as an activation energy source for amorphous indium-gallium-zinc-oxide (a-IGZO) thin film transistors (TFTs). High-pressure annealing (HPA) in nitrogen (N2) and oxygen (O2) gases was applied to activate a-IGZO TFTs at 100 °C at pressures in the range from 0.5 to 4 MPa. Activation of the a-IGZO TFTs during HPA is attributed to the effect of the high-pressure environment, so that the activation energy is supplied from the kinetic energy of the gas molecules. We reduced the activation temperature from 300 °C to 100 °C via the use of HPA. The electrical characteristics of a-IGZO TFTs annealed in O2 at 2 MPa were superior to those annealed in N2 at 4 MPa, despite the lower pressure. For O2 HPA under 2 MPa at 100 °C, the field effect mobility and the threshold voltage shift under positive bias stress were improved by 9.00 to 10.58 cm2/V.s and 3.89 to 2.64 V, respectively. This is attributed to not only the effects of the pressurizing effect but also the metal-oxide construction effect which assists to facilitate the formation of channel layer and reduces oxygen vacancies, served as electron trap sites.

  15. Study of Novel Floating-Gate Oxide Semiconductor Memory Using Indium-Gallium-Zinc Oxide for Low-Power System-on-Panel Applications

    Science.gov (United States)

    Yamauchi, Yoshimitsu; Kamakura, Yoshinari; Isagi, Yousuke; Matsuoka, Toshimasa; Malotaux, Satoshi

    2013-09-01

    A novel floating-gate oxide semiconductor (FLOTOS) memory using a wide-band-gap indium-gallium-zinc oxide (IGZO) is presented for low-power system-on-panel applications. An IGZO thin-film-transistor (TFT) is used as a memory transistor for controlling read current as well as a switching transistor for storing charges in a storage capacitor (Cs). The FLOTOS memory is fabricated using a standard IGZO TFT process without any additional process or mask steps. The proposed precharge-assisted threshold voltage compensation technique makes it possible to realize an infinite number of write cycles and a low-power write operation with a bit-line voltage of 5 V. Furthermore, excellent data retention longer than 10 h is obtained at 60 °C even under the worst bias-stress condition of read operation with the ultra low off-state leakage (2.8×10-20 A/µm) of the IGZO TFTs, which is estimated to be smaller by more than 7 orders of magnitude than that of polycrystalline silicon TFTs.

  16. Effect of top gate potential on bias-stress for dual gate amorphous indium-gallium-zinc-oxide thin film transistor

    Science.gov (United States)

    Chun, Minkyu; Um, Jae Gwang; Park, Min Sang; Chowdhury, Md Delwar Hossain; Jang, Jin

    2016-07-01

    We report the abnormal behavior of the threshold voltage (VTH) shift under positive bias Temperature stress (PBTS) and negative bias temperature stress (NBTS) at top/bottom gate in dual gate amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film transistors (TFTs). It is found that the PBTS at top gate shows negative transfer shift and NBTS shows positive transfer shift for both top and bottom gate sweep. The shift of bottom/top gate sweep is dominated by top gate bias (VTG), while bottom gate bias (VBG) is less effect than VTG. The X-ray photoelectron spectroscopy (XPS) depth profile provides the evidence of In metal diffusion to the top SiO2/a-IGZO and also the existence of large amount of In+ under positive top gate bias around top interfaces, thus negative transfer shift is observed. On the other hand, the formation of OH- at top interfaces under the stress of negative top gate bias shows negative transfer shift. The domination of VTG both on bottom/top gate sweep after PBTS/NBTS is obviously occurred due to thin active layer.

  17. High-density plasma etching characteristics of indium-gallium-zinc oxide thin films in CF{sub 4}/Ar plasma

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Young-Hee; Kim, Chang-Il

    2015-05-29

    We investigated the etching process of indium-gallium-zinc oxide (IGZO) thin films in an inductively coupled plasma system. The dry etching characteristics of the IGZO thin films were studied by varying the CF{sub 4}/Ar gas mixing ratio, RF power, DC-bias voltage, and process pressure. We determined the following optimized process conditions: an RF power of 700 W, a DC-bias voltage of − 150 V, and a process pressure of 2 Pa. A maximum etch rate of 25.63 nm/min for the IGZO thin films was achieved in a plasma with CF{sub 4}/Ar(= 25:75), and the selectivity of IGZO to Al and TiN was found to be 1.3 and 0.7, respectively. We determined the ionic composition of the CF{sub 4}/Ar plasma using optical emission spectroscopy. Analysis of chemical reactions at the IGZO thin film surfaces was performed using X-ray photoelectron spectroscopy. - Highlights: • IGZO thin film was etched by CF{sub 4}/Ar plasma as a function of gas mixing ratio. • IGZO bonds were broken Ar{sup +} sputtering and then reacted with the C-F{sub x} radicals. • The physical sputtering is dominant in etch control compared with chemical etching.

  18. Improvement in reliability of amorphous indium-gallium-zinc oxide thin-film transistors with Teflon/SiO2 bilayer passivation under gate bias stress

    Science.gov (United States)

    Fan, Ching-Lin; Tseng, Fan-Ping; Li, Bo-Jyun; Lin, Yu-Zuo; Wang, Shea-Jue; Lee, Win-Der; Huang, Bohr-Ran

    2016-02-01

    The reliability of amorphous indium-gallium-zinc oxide (a-IGZO) thin-film transistors (TFTs) with Teflon/SiO2 bilayer passivation prepared under positive and negative gate bias stresses (PGBS and NGBS, respectively) was investigated. Heavier electrical degradation was observed under PGBS than under NGBS, indicating that the environmental effects under PGBS are more evident than those under NGBS. The device with bilayer passivation under PGBS shows two-step degradation. The positive threshold voltage shifts during the initial stressing period (before 500 s), owing to the charges trapped in the gate insulator or at the gate insulator/a-IGZO active layer interface. The negative threshold voltage shift accompanies the increase in subthreshold swing (SS) for the continuous stressing period (after 500 s) owing to H2O molecules from ambience diffused within the a-IGZO TFTs. It is believed that Teflon/SiO2 bilayer passivation can effectively improve the reliability of the a-IGZO TFTs without passivation even though the devices are stressed under gate bias.

  19. Effect of top gate bias on photocurrent and negative bias illumination stress instability in dual gate amorphous indium-gallium-zinc oxide thin-film transistor

    Science.gov (United States)

    Lee, Eunji; Chowdhury, Md Delwar Hossain; Park, Min Sang; Jang, Jin

    2015-12-01

    We have studied the effect of top gate bias (VTG) on the generation of photocurrent and the decay of photocurrent for back channel etched inverted staggered dual gate structure amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film-transistors. Upon 5 min of exposure of 365 nm wavelength and 0.7 mW/cm2 intensity light with negative bottom gate bias, the maximum photocurrent increases from 3.29 to 322 pA with increasing the VTG from -15 to +15 V. By changing VTG from negative to positive, the Fermi level (EF) shifts toward conduction band edge (EC), which substantially controls the conversion of neutral vacancy to charged one (VO → VO+/VO2+ + e-/2e-), peroxide (O22-) formation or conversion of ionized interstitial (Oi2-) to neutral interstitial (Oi), thus electron concentration at conduction band. With increasing the exposure time, more carriers are generated, and thus, maximum photocurrent increases until being saturated. After negative bias illumination stress, the transfer curve shows -2.7 V shift at VTG = -15 V, which gradually decreases to -0.42 V shift at VTG = +15 V. It clearly reveals that the position of electron quasi-Fermi level controls the formation of donor defects (VO+/VO2+/O22-/Oi) and/or hole trapping in the a-IGZO /interfaces.

  20. Properties of c-axis-aligned crystalline indium-gallium-zinc oxide field-effect transistors fabricated through a tapered-trench gate process

    Science.gov (United States)

    Asami, Yoshinobu; Kurata, Motomu; Okazaki, Yutaka; Higa, Eiji; Matsubayashi, Daisuke; Okamoto, Satoru; Sasagawa, Shinya; Moriwaka, Tomoaki; Kakehata, Tetsuya; Yakubo, Yuto; Kato, Kiyoshi; Hamada, Takashi; Sakakura, Masayuki; Hayakawa, Masahiko; Yamazaki, Shunpei

    2016-04-01

    To achieve both low power consumption and high-speed operation, we fabricated c-axis-aligned crystalline indium-gallium-zinc oxide (CAAC-IGZO) field-effect transistors (FETs) with In-rich IGZO and common IGZO (\\text{In}:\\text{Ga}:\\text{Zn} = 1:1:1 in atomic ratio) active layers through a simple process using trench gates, and evaluated their characteristics. The results confirm that 60-nm-node IGZO FETs fabricated through a 450 °C process show an extremely low off-state current below the detection limit (at most 2 × 10-16 A) even at a measurement temperature of 150 °C. The results also reveal that the FETs with the In-rich IGZO active layer show a higher on-state current than those with the common IGZO active layer and have excellent frequency characteristics with a cutoff frequency and a maximum oscillation frequency of up to 20 and 6 GHz, respectively. Thus, we demonstrated that CAAC-IGZO FETs with trench gates are promising for achieving both low power consumption and high-speed operation.

  1. Indium-gallium-zinc-oxide layer used to increase light transmittance efficiency of adhesive layer for stacked-type multijunction solar cells

    Science.gov (United States)

    Yoshidomi, Shinya; Kimura, Shunsuke; Hasumi, Masahiko; Sameshima, Toshiyuki

    2015-11-01

    We report the increase in transmittance efficiency of the intermediate layer for multijunction solar cells caused by the indium-gallium-zinc-oxide (IGZO) layer used as the antireflection layer. Si substrates coated with a 200-nm-thick IGZO layer with a refractive index of 1.85 were prepared. The resistivity of the IGZO layer was increased from 0.0069 (as-deposited) to 0.032 Ω cm by heat treatment at 350 °C for 1 h to prevent free-carrier optical absorption. Samples with the Si/IGZO/adhesive/IGZO/Si structure were fabricated. The average transmissivity for wavelengths between 1200 and 1600 nm was 49%, which was close to 55% of single-crystal silicon substrates. A high effective transmittance efficiency of 89% was experimentally achieved. The numerical calculation showed in an effective transmittance efficiency of 99% for 170-nm-thick antireflection layers with a resistivity of 0.6 Ω cm and a refractive index of 2.1.

  2. Acoustic and NMR investigations of melting and crystallization of indium-gallium alloys in pores of synthetic opal matrices

    Science.gov (United States)

    Pirozerskii, A. L.; Charnaya, E. V.; Lee, M. K.; Chang, L. J.; Nedbai, A. I.; Kumzerov, Yu. A.; Fokin, A. V.; Samoilovich, M. I.; Lebedeva, E. L.; Bugaev, A. S.

    2016-05-01

    The paper presents the results of studying the crystallization and melting processes of Ga-In eutectic alloys, which are embedded in opal matrices, using acoustic and NMR methods. The indium concentrations in the alloys were 4, 6, 9, and 15 at %. Measurements were performed upon cooling from room temperature to complete crystallization of the alloys and subsequent heating. It is revealed how the size effects and alloy composition influence the formation of phases with α- and β-Ga structures and on changes in the melting-temperature ranges. A difference was observed between the results obtained using acoustic and NMR methods, which was attributed to different temperature measurement conditions.

  3. Growth of 1.5 micron gallium indium nitrogen arsenic antimonide vertical cavity surface emitting lasers by molecular beam epitaxy

    Science.gov (United States)

    Wistey, Mark Allan

    Fiber optics has revolutionized long distance communication and long haul networks, allowing unimaginable data speeds and noise-free telephone calls around the world for mere pennies per hour at the trunk level. But the high speeds of optical fiber generally do not extend to individual workstations or to the home, in large part because it has been difficult and expensive to produce lasers which emitted light at wavelengths which could take advantage of optical fiber. One of the most promising solutions to this problem is the development of a new class of semiconductors known as dilute nitrides. Dilute nitrides such as GaInNAs can be grown directly on gallium arsenide, which allows well-established processing techniques. More important, gallium arsenide allows the growth of vertical-cavity surface-emitting lasers (VCSELs), which can be grown in dense, 2D arrays on each wafer, providing tremendous economies of scale for manufacturing, testing, and packaging. Unfortunately, GaInNAs lasers have suffered from what has been dubbed the "nitrogen penalty," with high thresholds and low efficiency as the fraction of nitrogen in the semiconductor was increased. This thesis describes the steps taken to identify and essentially eliminate the nitrogen penalty. Protecting the wafer surface from plasma ignition, using an arsenic cap, greatly improved material quality. Using a Langmuir probe, we further found that the nitrogen plasma source produced a large number of ions which damaged the wafer during growth. The ions were dramatically reduced using deflection plates. Low voltage deflection plates were found to be preferable to high voltages, and simulations showed low voltages to be adequate for ion removal. The long wavelengths from dilute nitrides can be partly explained by wafer damage during growth. As a result of these studies, we demonstrated the first CW, room temperature lasers at wavelengths beyond 1.5mum on gallium arsenide, and the first GaInNAs(Sb) VCSELs beyond 1

  4. Influence of addition of indium and of post-annealing on structural, electrical and optical properties of gallium-doped zinc oxide thin films deposited by direct-current magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Pham, Duy Phong [Laboratory of Advanced Materials, University of Science, Vietnam National University, HoChiMinh (Viet Nam); College of Information and Communication Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Nguyen, Huu Truong [Laboratory of Advanced Materials, University of Science, Vietnam National University, HoChiMinh (Viet Nam); Phan, Bach Thang [Laboratory of Advanced Materials, University of Science, Vietnam National University, HoChiMinh (Viet Nam); Faculty of Materials Science, University of Science, Vietnam National University, HoChiMinh (Viet Nam); Hoang, Van Dung [Laboratory of Advanced Materials, University of Science, Vietnam National University, HoChiMinh (Viet Nam); Maenosono, Shinya [School of Materials Science, Japan Advanced Institute of Science and Technology, 1-1 Asahidai, Nomi, Ishikawa 923-1292 (Japan); Tran, Cao Vinh, E-mail: tcvinh@hcmus.edu.vn [Laboratory of Advanced Materials, University of Science, Vietnam National University, HoChiMinh (Viet Nam)

    2015-05-29

    In this study, both gallium-doped zinc oxide (GZO) and indium-added gallium-doped zinc oxide (IGZO) thin films were deposited on commercial glasses by magnetron dc-sputtering in argon atmosphere. The crystal structure, electrical conductivity and optical transmission of as-deposited as well as post-annealed thin films of both GZO and IGZO were investigated for comparison. A small amount of indium introduced into GZO thin films had improved their polycrystalline structure and increased their electrical conductivity by over 29%. All obtained GZO and IGZO thin films have strong [002] crystalline direction, a characteristic orientation of ZnO thin films. Although post-annealed in air at high temperatures up to 500 °C, IGZO thin films still had very low sheet resistance of 6.6 Ω/□. Furthermore, they had very high optical transmission of over 80% in both visible and near-infrared regions. - Highlights: • Doping 0.1 at.% indium enhanced crystalline, electrical properties of GZO films. • The mobility of IGZO films was 25% higher than that of GZO films. • The IGZO films will be potential materials for transparent conducting electrodes.

  5. Evaluation of the indium gallium nitride/silicon broken-gap heterojunction and its potential application for solar cells

    Science.gov (United States)

    Yao, Yuan

    InGaN (especially In-rich alloy) has been actively studied for decades since the band gap of InN was revised downward from ˜2.0 eV to 0.64 eV. The potential applications for alloys of In-rich InGaN hence became apparent. Despite the promising potential, photovoltaic devices based on InGaN have struggled due to a number of key limitations and fundamental physical problems. Firstly, due to the deep excursion of the InN conduction band at the gamma point, defects in InN are almost universally n-type leading to unintentional degenerate doping. This also leads to the problem of electron accumulation at all surfaces and interfaces of InN. Secondly, p-type doping is problematic, partially due to the degenerate doping effect of defects, but it has also been observed that Mg-doping, while leading to a p-type layer, dramatically reduces the quantum efficiency. This thesis explores an alternative approach using n-type InGaN to form a heterojunction with a p-type Si substrate. One potential benefit to using p-type Si as a substrate material for InGaN is that the valence band of Si possibly lines up with the conduction band of InGaN for a specific mole fraction of indium. Such a band alignment is known as a broken gap heterojunction, an example of which is the interface between InAs and AlxGa 1--xSb. The benefits of this broken-gap junction include a low series resistance, high electron mobility, and mobility only weakly dependent on temperature. These properties enable new approach to photovoltaic devices. The InGaN/Si heterojunctions were fabricated by plasma-assisted molecular beam epitaxy under stoichiometric flux conditions. An ultra-thin SiN interface layer was introduced, by Si nitridation process, to passivate the substrate surface and prevent In-Si and Ga-Si eutectic problems. InGaN films with a variety of indium mole fractions were grown by calibrating the In/Ga flux ratio during the deposition. The chemical composition of as-grown films was characterized by x

  6. Non-invasive Drosophila ECG recording by using eutectic gallium-indium alloy electrode: a feasible tool for future research on the molecular mechanisms involved in cardiac arrhythmia.

    Directory of Open Access Journals (Sweden)

    Po-Hung Kuo

    Full Text Available BACKGROUND: Drosophila heart tube is a feasible model for cardiac physiological research. However, obtaining Drosophila electrocardiograms (ECGs is difficult, due to the weak signals and limited contact area to apply electrodes. This paper presents a non-invasive Gallium-Indium (GaIn based recording system for Drosophila ECG measurement, providing the heart rate and heartbeat features to be observed. This novel, high-signal-quality system prolongs the recording time of insect ECGs, and provides a feasible platform for research on the molecular mechanisms involved in cardiovascular diseases. METHODS: In this study, two types of electrode, tungsten needle probes and GaIn electrodes, were used respectively to noiselessly conduct invasive and noninvasive ECG recordings of Drosophila. To further analyze electrode properties, circuit models were established and simulated. By using electromagnetic shielded heart signal acquiring system, consisted of analog amplification and digital filtering, the ECG signals of three phenotypes that have different heart functions were recorded without dissection. RESULTS AND DISCUSSION: The ECG waveforms of different phenotypes of Drosophila recorded invasively and repeatedly with n value (n>5 performed obvious difference in heart rate. In long period ECG recordings, non-invasive method implemented by GaIn electrodes acts relatively stable in both amplitude and period. To analyze GaIn electrode, the correctness of GaIn electrode model established by this paper was validated, presenting accuracy, stability, and reliability. CONCLUSIONS: Noninvasive ECG recording by GaIn electrodes was presented for recording Drosophila pupae ECG signals within a limited contact area and signal strength. Thus, the observation of ECG changes in normal and SERCA-depleted Drosophila over an extended period is feasible. This method prolongs insect survival time while conserving major ECG features, and provides a platform for

  7. Effect of top gate bias on photocurrent and negative bias illumination stress instability in dual gate amorphous indium-gallium-zinc oxide thin-film transistor

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eunji; Chowdhury, Md Delwar Hossain; Park, Min Sang; Jang, Jin, E-mail: jjang@khu.ac.kr [Advanced Display Research Center and Department of Information Display, Kyung Hee University, Seoul 130-701 (Korea, Republic of)

    2015-12-07

    We have studied the effect of top gate bias (V{sub TG}) on the generation of photocurrent and the decay of photocurrent for back channel etched inverted staggered dual gate structure amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film-transistors. Upon 5 min of exposure of 365 nm wavelength and 0.7 mW/cm{sup 2} intensity light with negative bottom gate bias, the maximum photocurrent increases from 3.29 to 322 pA with increasing the V{sub TG} from −15 to +15 V. By changing V{sub TG} from negative to positive, the Fermi level (E{sub F}) shifts toward conduction band edge (E{sub C}), which substantially controls the conversion of neutral vacancy to charged one (V{sub O} → V{sub O}{sup +}/V{sub O}{sup 2+} + e{sup −}/2e{sup −}), peroxide (O{sub 2}{sup 2−}) formation or conversion of ionized interstitial (O{sub i}{sup 2−}) to neutral interstitial (O{sub i}), thus electron concentration at conduction band. With increasing the exposure time, more carriers are generated, and thus, maximum photocurrent increases until being saturated. After negative bias illumination stress, the transfer curve shows −2.7 V shift at V{sub TG} = −15 V, which gradually decreases to −0.42 V shift at V{sub TG} = +15 V. It clearly reveals that the position of electron quasi-Fermi level controls the formation of donor defects (V{sub O}{sup +}/V{sub O}{sup 2+}/O{sub 2}{sup 2−}/O{sub i}) and/or hole trapping in the a-IGZO /interfaces.

  8. Effect of direct current sputtering power on the behavior of amorphous indium-gallium-zinc-oxide thin-film transistors under negative bias illumination stress: A combination of experimental analyses and device simulation

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Jun Tae; Kim, Dong Myong; Choi, Sung-Jin; Kim, Dae Hwan, E-mail: khs3297@cnu.ac.kr, E-mail: drlife@kookmin.ac.kr [School of Electrical Engineering, Kookmin University, Seoul 136-702 (Korea, Republic of); Park, Jozeph [Department of Materials Science and Engineering, KAIST, Daejeon 305-701 (Korea, Republic of); Ahn, Byung Du [School of Electrical and Electronic Engineering, Yonsei University, Seodaemun-gu, Seoul 120-749 (Korea, Republic of); Kim, Hyun-Suk, E-mail: khs3297@cnu.ac.kr, E-mail: drlife@kookmin.ac.kr [Department of Materials Science and Engineering, Chungnam National University, Daejeon 305-764 (Korea, Republic of)

    2015-03-23

    The effect of direct current sputtering power of indium-gallium-zinc-oxide (IGZO) on the performance and stability of the corresponding thin-film transistor devices was studied. The field effect mobility increases as the IGZO sputter power increases, at the expense of device reliability under negative bias illumination stress (NBIS). Device simulation based on the extracted sub-gap density of states indicates that the field effect mobility is improved as a result of the number of acceptor-like states decreasing. The degradation by NBIS is suggested to be induced by the formation of peroxides in IGZO rather than charge trapping.

  9. A chronic toxicity test for the tropical marine snail Nassarius dorsatus to assess the toxicity of copper, aluminium, gallium, and molybdenum.

    Science.gov (United States)

    Trenfield, Melanie A; van Dam, Joost W; Harford, Andrew J; Parry, David; Streten, Claire; Gibb, Karen; van Dam, Rick A

    2016-07-01

    Chronic toxicity test methods for assessing the toxicity of contaminants to tropical marine organisms are generally lacking. A 96-h chronic growth rate toxicity test was developed for the larval stage of the tropical dogwhelk, Nassarius dorsatus. Growth rates of N. dorsatus larvae were assessed following exposures to copper (Cu), aluminium (Al), gallium (Ga), and molybdenum (Mo). Exposure to Cu at 28 °C validated the sensitivity of the test method, with 10% (EC10) and 50% (EC50) effect concentrations of 4.2 μg/L and 7.3 μg/L Cu, respectively. The EC10 and EC50 values for Al (toxicity of Cu and Al was also assessed at 24 °C and 31 °C, representing average year-round water temperatures for subtropical and tropical Australian coastal environments. At 24 °C, the growth rate of control larvae was reduced by 52% compared with the growth rate at 28 °C and there was an increase in sensitivity to Cu (EC50 = 4.7 μg/L) but a similar sensitivity to Al (EC50 = 180 μg/L). At 31 °C the control growth rate increased by 35% from that measured at 28 °C and there was reduced sensitivity to both Cu and Al (EC50s = 8.5 μg/L and 642 μg/L, respectively). There was minimal toxicity resulting from Ga (EC50 = 4560 μg/L) and Mo (no effect at ≤7000 μg/L Mo). Environ Toxicol Chem 2016;35:1788-1795. © 2015 SETAC.

  10. Ambient temperature deposition of gallium nitride/gallium oxynitride from a deep eutectic electrolyte, under potential control.

    Science.gov (United States)

    Sarkar, Sujoy; Sampath, S

    2016-05-11

    A ternary, ionically conducting, deep eutectic solvent based on acetamide, urea and gallium nitrate is reported for the electrodeposition of gallium nitride/gallium indium nitride under ambient conditions; blue and white light emitting photoluminescent deposits are obtained under potential control. PMID:27074315

  11. Influence of the charge trap density distribution in a gate insulator on the positive-bias stress instability of amorphous indium-gallium-zinc oxide thin-film transistors

    Science.gov (United States)

    Kim, Eungtaek; Kim, Choong-Ki; Lee, Myung Keun; Bang, Tewook; Choi, Yang-Kyu; Park, Sang-Hee Ko; Choi, Kyung Cheol

    2016-05-01

    We investigated the positive-bias stress (PBS) instability of thin film transistors (TFTs) composed of different types of first-gate insulators, which serve as a protection layer of the active surface. Two different deposition methods, i.e., the thermal atomic layer deposition (THALD) and plasma-enhanced ALD (PEALD) of Al2O3, were applied for the deposition of the first GI. When THALD was used to deposit the GI, amorphous indium-gallium-zinc oxide (a-IGZO) TFTs showed superior stability characteristics under PBS. For example, the threshold voltage shift (ΔVth) was 0 V even after a PBS time (tstress) of 3000 s under a gate voltage (VG) condition of 5 V (with an electrical field of 1.25 MV/cm). On the other hand, when the first GI was deposited by PEALD, the ΔVth value of a-IGZO TFTs was 0.82 V after undergoing an identical amount of PBS. In order to interpret the disparate ΔVth values resulting from PBS quantitatively, the average oxide charge trap density (NT) in the GI and its spatial distribution were investigated through low-frequency noise characterizations. A higher NT resulted during in the PEALD type GI than in the THALD case. Specifically, the PEALD process on a-IGZO layer surface led to an increasing trend of NT near the GI/a-IGZO interface compared to bulk GI owing to oxygen plasma damage on the a-IGZO surface.

  12. Remarkable changes in interface O vacancy and metal-oxide bonds in amorphous indium-gallium-zinc-oxide thin-film transistors by long time annealing at 250 °C

    International Nuclear Information System (INIS)

    We have studied the effect of long time post-fabrication annealing on negative bias illumination stress (NBIS) of amorphous indium-gallium-zinc-oxide (a-IGZO) thin-film-transistors. Annealing for 100 h at 250 °C increased the field effect mobility from 14.7 cm2/V s to 17.9 cm2/V s and reduced the NBIS instability remarkably. Using X-ray photoelectron spectroscopy, the oxygen vacancy and OH were found to exist at the interfaces of a-IGZO with top and bottom SiO2. Long time annealing helps to decrease the vacancy concentration and increase the metal-oxygen bonds at the interfaces; this leads to increase in the free carrier concentrations in a-IGZO and field-effect mobility. X-ray reflectivity measurement indicated the increment of a-IGZO film density of 5.63 g cm−3 to 5.83 g cm−3 (3.4% increase) by 100 h annealing at 250 °C. The increase in film density reveals the decrease of O vacancy concentration and reduction of weak metal-oxygen bonds in a-IGZO, which substantially helps to improve the NBIS stability

  13. Development trend and direction of application of indium gallium zinc oxide TFT-LCD to IGZO Technology%金属氧化物(IGZO)TFT-LCD的工艺技术发展趋势及方向

    Institute of Scientific and Technical Information of China (English)

    黄伟剑

    2016-01-01

    铟镓锌氧化物IGZO(indium gallium zinc oxide)是用于新一代薄膜液晶显示屏薄膜晶体管沟道层的材料.研究铟镓锌金属氧化物IGZO在TFT-LCD制造应用中的工艺技术发展趋势及方向.分析了铟镓锌氧化物IGZO在TFT-LCD中的作用和使用现状,分析了TFT-LCD液晶显示器的功能特性和技术特点.结合金属氧化物IGZO的应用,阐述了未来TFT-LCD液晶显示器发展的趋势和方向,TFT-LCD的工艺技术将向着高集成度,高环保性、高分辨率、高水平垂直角、高显示亮度、长使用寿命周期等方向发展,随着大面积低温多晶硅TFT-LCD的使用,TFT-LCD发展空间广阔,将迅速成为当前和未来液晶显示器的主流产品.

  14. Separation of indium(Ⅲ),gallium(Ⅲ),and zinc(Ⅱ) with Levextrel resin containing di(2-ethylhexyl) phosphoric acid (CL-P204):Part Ⅱ.Mechanism and kinetics of adsorbing indium(Ⅲ)

    Institute of Scientific and Technical Information of China (English)

    LIU Junshen; ZHOU Baoxue; CAI Chunguang; CAI Jun; CAI Weimin

    2004-01-01

    The mechanism of adsorbing indium(Ⅲ) from sulfate solutions with CL-P204 Levextrel resin containing di(-2-ethylhexyl) phosphoric acid was examined by batch operation and infrared spectra. The results showed that the P204 adsorbed on the resin behaved in the similar way to solvent extraction except that it was as a monomer in resin adsorbing but in dimeric form in solvent extraction. Three factors including temperature, indium(Ⅲ) concentration of solution, and the size of resin particles which influence the In3+/H+ exchange on CL-P204 Levextrel resin were investigated by the modified limited batch technique in order to determine the kinetics of In3+/H+ exchange. It was found that the rate of ion exchange increased with the temperature and the concentration of solution increasing and with the size of the resin particles decreasing.According to the expression developed by Boyd et al., the controlling factor of In3+/H+ exchange on CL-P204 Levextrel resin was the diffusion through the resin particles. The effective diffusion coefficient, activation energy, and entropy of activation in the particle-diffusion were determined as 1.57 x l0-10 m2/s, 11.9 KJ/mol, -84.1 J/(mol. K), respectively.

  15. Quantitative bone gallium scintigraphy in osteomyelitis

    International Nuclear Information System (INIS)

    Gallium imaging offers many practical advantages over indium-111-labeled leukocyte imaging, and calculating quantitative ratios in addition to performing the routine bone-gallium images allows accurate and easy evaluation of patients with suspected osteomyelitis. To add objectivity and improve the accuracy and confidence in diagnosis of osteomyelitis, quantitative comparison of abnormalities seen on bone scans and gallium scans was performed. One hundred and ten adult patients with 126 sites of suspected osteomyelitis were evaluated and categorized by gallium-to-bone ratios, gallium-to-background ratios, and spatial incongruency of gallium and bone activity. Combined evaluation using these criteria gave a 70% sensitivity and 93% specificity for the diagnosis of osteomyelitis. (orig.)

  16. Improving the efficiency of copper indium gallium (Di-selenide (CIGS solar cells through integration of a moth-eye textured resist with a refractive index similar to aluminum doped zinc oxide

    Directory of Open Access Journals (Sweden)

    M. Burghoorn

    2014-12-01

    Full Text Available Textured transparent conductors are widely used in thin-film silicon solar cells. They lower the reflectivity at interfaces between different layers in the cell and/or cause an increase in the path length of photons in the Si absorber layer, which both result in an increase in the number of absorbed photons and, consequently, an increase in short-circuit current density (Jsc and cell efficiency. Through optical simulations, we recently obtained strong indications that texturing of the transparent conductor in copper indium gallium (di-selenide (CIGS solar cells is also optically advantageous. Here, we experimentally demonstrate that the Jsc and efficiency of CIGS solar cells with an absorber layer thickness (dCIGS of 0.85 μm, 1.00 μm and 2.00 μm increase through application of a moth-eye textured resist with a refractive index that is sufficiently similar to AZO (nresist = 1.792 vs. nAZO = 1.913 at 633 nm to avoid large optical losses at the resist-AZO interface. On average, Jsc increases by 7.2%, which matches the average reduction in reflection of 7.0%. The average relative increase in efficiency is slightly lower (6.0%. No trend towards a larger relative increase in Jsc with decreasing dCIGS was observed. Ergo, the increase in Jsc can be fully explained by the reduction in reflection, and we did not observe any increase in Jsc based on an increased photon path length.

  17. Effect of gallium,aluminium,and chromium on silica supported V-Mg-O catalysts during oxidative dehydrogenation of propane:Kinetic study

    Institute of Scientific and Technical Information of China (English)

    B.Ravi Kumar; Rajeev Kumar

    2008-01-01

    The oxidative dehydrogenation(ODH)of propane was conducted on gallium,aluminum.and chromium doped Si30VMgO catalysts.On doping,the concentrations of the phases responsible for the activity and selectivity increased in their concentrations.The reaction studies were conducted in a tubular steel reactor at temperatures of 753,783,813.and 843 K and atmospheric pressure.The total flow rates of the feed were chosen as 30,40,50,and 60 ml/min.The propane to oxygen ratios were chosen at 1:1,2:1,and 3:1,respectively.The effect of various dopants on the activity and selectivity of the catalysts was studied.Deactivation studies were conducted over all the catalysts.The kinetic data were analyzed in terms of power law models and Langmuir-Hinshelwood(LH)models.The kinetic data results were analyzed by comparing the effect of dopants.Statistical model discrimination was done for the proposed models.AIC and BIC criteria were used for discrimination of the models.

  18. The Availability of Indium: The Present, Medium Term, and Long Term

    Energy Technology Data Exchange (ETDEWEB)

    Lokanc, Martin [Colorado School of Mines, Golden, CO (United States); Eggert, Roderick [Colorado School of Mines, Golden, CO (United States); Redlinger, Michael [Colorado School of Mines, Golden, CO (United States)

    2015-10-01

    Demand for indium is likely to increase if the growth in deployment of the copper-indium-gallium-selenide (CIGS) and III-V thin-film photovoltaic technologies accelerates. There are concerns about indium supply constraints since it is relatively rare element in the earth's crust and because it is produced exclusively as a byproduct.

  19. 射频磁控溅射低温制备非晶铟镓锌氧薄膜晶体管%Fabrication of Amorphous Indium Gallium Zinc Oxide Thin Film Transistor at Low Temperature by RF Magnetron Sputtering

    Institute of Scientific and Technical Information of China (English)

    信恩龙; 李喜峰; 陈龙龙; 石继锋; 李春亚; 张建华

    2012-01-01

    The indium gallium zinc oxide (IGZO) thin films were fabricated by RF magnetron sputtering at room temperature in this paper. The crystal structure, surface morphology, and optical electrical of the IGZO films were investigated by X-ray diffraction ( XRD) , atom force microscopy (AFM) , and photometry, respectively. The results revealed that the IGZO film was amorphous, the surface of the films was uniform and smooth. A good optical transmittance of over 80% was obtained in the visible light. The IGZO thin film transistors were successfully fabricated at low temperature ( < 200℃ ) using the room temperature sputtering IGZO thin film as the active layer. The field effect mobility of a-IGZO TFT was larger than 6. 0 cm2 · V-1·s-1. The device's on/off ratio was 10~7, threshold voltage was 1.2 V and subthreshold voltage swing is 0.9 V/ dec. Constant bias stress testing showed that the a-IGZO TFT threshold voltage exhibited positive shifts as time increased.%利用射频磁控溅射技术室温制备了铟镓锌氧(IGZO)薄膜,采用X射线衍射(XRD)表征薄膜的晶体结构,原子力显微镜(AFM)观察其表面形貌,分光光度计测量其透光率.结果表明:室温制备的IGZO薄膜为非晶态且薄膜表面均匀平整,可见光透射率大于80%.将室温制备的IGZO薄膜作为有源层,在低温(<200℃)条件下成功地制备了铟镓锌氧薄膜晶体管(a-IGZO TFT),获得的a-IGZO-TFT器件的场效应迁移率大于6.0cm2·V-1·s-1,开关比约为107,阈值电压为1.2V,亚阈值摆蝠(S)约为0.9 V/dec,偏压应力测试a-IGZO TFT阈值电压随时间向右漂移.

  20. Characterisation of Ga-coated and Ga-brazed aluminium

    Energy Technology Data Exchange (ETDEWEB)

    Ferchaud, E. [Universite de Nantes, Polytech' Nantes, Laboratoire Genie des Materiaux et Procedes Associes, Rue Christian Pauc, 44306 Nantes Cedex 3 (France); Christien, F., E-mail: frederic.christien@univ-nantes.fr [Universite de Nantes, Polytech' Nantes, Laboratoire Genie des Materiaux et Procedes Associes, Rue Christian Pauc, 44306 Nantes Cedex 3 (France); Barnier, V. [Ecole Nationale Superieure des Mines, MPI, CNRS UMR5146, Centre SMS, 158 Cours Fauriel, 42023 Saint Etienne (France); Paillard, P. [Universite de Nantes, Polytech' Nantes, Laboratoire Genie des Materiaux et Procedes Associes, Rue Christian Pauc, 44306 Nantes Cedex 3 (France)

    2012-05-15

    This work is devoted to the brazing of aluminium using liquid gallium. Gallium was deposited on aluminium samples at {approx} 50 Degree-Sign C using a liquid gallium 'polishing' technique. Brazing was undertaken for 30 min at 500 Degree-Sign C in air. EDS (Energy Dispersive X-ray Spectroscopy) and AES (Auger Electron Spectroscopy) characterisation of Ga-coated samples has shown that the Ga surface layer thickness is of ten (or a few tens of) nanometres. Furthermore, aluminium oxide layer (Al{sub 2}O{sub 3}) was shown to be 'descaled' during Ga deposition, which ensures good conditions for further brazing. Cross-section examination of Ga-coated samples shows that liquid gallium penetrates into the aluminium grain boundaries during deposition. The thickness of the grain boundary gallium film was measured using an original EDS technique and is found to be of a few tens of nanometres. The depth of gallium grain boundary penetration is about 300 {mu}m at the deposition temperature. The fracture stress of the brazed joints was measured from tensile tests and was determined to be 33 MPa. Cross-section examination of brazed joints shows that gallium has fully dissolved into the bulk and that the joint is really autogenous. - Highlights: Black-Right-Pointing-Pointer Aluminium can be brazed using liquid gallium deposited by a 'polishing' technique. Black-Right-Pointing-Pointer The aluminium oxide layer is 'descaled' during liquid Ga 'polishing' deposition. Black-Right-Pointing-Pointer EDS can be used for determination of surface and grain boundary Ga film thickness. Black-Right-Pointing-Pointer The surface and grain boundary Ga film thickness is of a few tens of nm. Black-Right-Pointing-Pointer Surface and grain boundary gallium dissolves in the bulk during brazing.

  1. 氧分压对铟镓锌氧薄膜晶体管性能影响%Effect of oxygen partial pressure on the performance of indium gallium zinc oxide thin film transistor

    Institute of Scientific and Technical Information of China (English)

    孙建明; 周婷婷; 任庆荣; 胡合合; 陈宁; 宁策; 王路; 刘文渠; 李东升

    2016-01-01

    采用标准的液晶显示屏基板制备工艺制备出铟镓锌氧薄膜晶体管(IGZO-TFT),通过调节 IGZO 薄膜工艺中氧分压,研究不同氧分压对TFT器件电学性能的影响.实验结果表明,所有器件都展现出良好的电学特性,随着氧分压从10%增加到50%,TFT的阈值电压由0.5 V增加到2.2 V,而亚阈值摆幅没有发生变化.在栅极施加30 V偏压3600 s后,随着氧分压的增加,阈值电压向正向的漂移量由1 V增加到9 V.经过分析得出高氧分压的 IGZO-TFT器件中载流子浓度低,建立相同导电能力的沟道时所需要栅极电压会更大,阈值电压会增加.而在金属-绝缘层-半导体(MIS)结构中低载流子浓度会导致有源层能带弯曲的部分包含更多与电子陷阱相同的能态,栅介质层(GI)会俘获更多的电子,造成阈值电压漂移量较大的现象.%Indium gallium zinc oxide thin film transistors (IGZO-TFT)were fabricated with the stand-ard process of TFT-LCD arrays substrate.The effects of different oxygen partial pressure on IGZO-TFT performance were investigated by adj usting the oxygen partial pressure in IGZO film process.All devices showed good electrical properties.The threshold voltage of TFT was increased from 0.5 V to 2.2 V as the oxygen partial pressure was increased from 10% to 50%,whereas the sub-threshold swing had not changed.Applying a positive gate bias of 30 V for 3 600 s,with the increase of the oxy-gen partial pressure,the positive shift of threshold voltage of IGZO-TFT was increased from 1 V to 9 V.The carrier concentration in TFT with higher oxygen partial pressure is lower.So it requires high-er gate voltage for building the channel with the same conductive capability,and therefore the thresh-old voltage will be higher.In the Metal-Insulator-Semiconductor (MIS)structure,the lower carrier concentration leads electron accumulation layer to be thicker.There will be more energy states in band bending part of active layer which

  2. Preparation of gallium-68 radiopharmaceuticals for positron tomography. Progress report, November 1, 1983-May 31, 1986

    International Nuclear Information System (INIS)

    The work described in this paper centers on the development and assessment of an improved germanium-68/gallium-68 generator, the testing and evaluation of simple germanium/gallium compounds for use with PET, and on methods of attaching gallium and indium to proteins for use with PET as well as indium-111 and conventional images. This work has expanded to use this technology with monoclonal antibodies. We are also studying the mechanisms and stability of binding of these metals to these modified proteins. The syntheses and assessment of new ligands, specifically aimed at measurement of myocardial and brain blood flow are also described. 7 figs., 11 tabs

  3. 高迁移率非晶铟镓锌氧化物薄膜晶体管的制备与特性研究%The preparation and characteristics research of high mobility amorphous indium gallium zinc oxide thin-film transistors∗

    Institute of Scientific and Technical Information of China (English)

    李帅帅; 梁朝旭; 王雪霞; 李延辉; 宋淑梅; 辛艳青; 杨田林†

    2013-01-01

      由于铟镓锌氧化物(IGZO)薄膜具有高迁移率和高透过率的特点,它作为有源层被广泛的应用于薄膜晶体管(TFT).本文利用磁控溅射方法制备了TFT的有源层IGZO和源漏电极,用简单低成本的掩膜法控制沟道的尺寸,制备了具有高迁移率、底栅结构的n型非晶铟镓锌氧化物薄膜晶体管(IGZO-TFT).利用X射线衍射仪(XRD)和紫外可见光分光光度计分别测试了IGZO薄膜的衍射图谱和透过率图谱,研究了IGZO薄膜的结构和光学特性.通过测试IGZO-TFT的输出特性和转移特性曲线,讨论了IGZO有源层厚度对IGZO-TFT特性的影响.制备的IGZO-TFT器件的场效应迁移率高达15.6 cm2·V−1·s−1,开关比高于107.%Indium gallium zinc oxide (IGZO) is widely used in thin-film transistors (TFT) as an active layer due to its high mobility and transmittance. The amorphous n-type indium gallium zinc oxide thin-film transistors (IGZO-TFT) of bottom gate with high mobility were prepared, the active layer, source and drain electrode of the TFT were prepared by using magnetron sputtering method, and a low cost mask was used to control the size of the channel. The diffraction pattern and transmittance spectrum were measured by using X-ray diffraction and ultraviolet–visible spectrophotometer, respectively. The structural and optical properties of the IGZO thin film were studied. The dependence of active layer thickness on the performance was analyzed by testing the output characteristics and transfer property of IGZO-TFT. The field effect mobility of the IGZO-TFT reaches 15.6 cm2·V−1·s−1, and the on/off ratio is higher than 107.

  4. Gallium Arsenide

    Science.gov (United States)

    Brozel, Mike

    The history of gallium arsenide is complicated because the technology required to produce GaAs devices has been fraught with problems associated with the material itself and with difficulties in its fabrication. Thus, for many years, GaAs was labelled as "the semiconductor of the future, and it will always be that way." Recently, however, advances in compact-disc (CD) technology, fibre-optic communications and mobile telephony have boosted investment in GaAs research and development. Consequently, there have been advances in materials and fabrication technology and, as a result, GaAs devices now enjoy stable niche markets.

  5. 铜-钼源漏电极对非晶氧化铟镓锌薄膜晶体管性能的改善∗%Improved p erformance of the amorphous indium-gallium-zinc oxide thin film transistor with Cu-Mo source/drain electro de

    Institute of Scientific and Technical Information of China (English)

    宁洪龙; 王磊; 兰林锋; 彭俊彪; 胡诗犇; 朱峰; 姚日晖; 徐苗; 邹建华; 陶洪; 徐瑞霞; 徐华

    2015-01-01

    Copper is an alternative material for aluminum electrode to meet the stringent requirement for high mobility and low resistance-capacitance (RC) delay of amorphous indium-gallium-zinc oxide (a-IGZO) thin film transistor (TFT) for next generation of display technology due to its intrinsic high conductivity. However, low bonding strength between copper layer and insulator/glass and easy diffusion into active layer restrict its application in the field of TFT. In this work, a 30 nm thin film of molybdenum is introduced into copper electrode to form a copper-molybdenum source/drain electrode of a-IGZO TFT, which not only inhibits the diffusion of copper, but also enhances the interfacial adhesion between electrode and substrate. The obtained Cu-Mo TFT possesses a high mobility of∼9.26 cm2·V−1·s−1 and a low subthreshold swing of 0.11 V/Decade. Moreover, it has shorter current transfer length(∼0.2 µm), lower contact resistance (∼1072 Ω), and effective contact resistance (∼1 × 10−4 Ω·cm2) than the pure copper electrode. Cu-Mo electrode with low contact resistance and high adhesion to substrates paves the way to the application of copper in high conductivity interconnection of a-IGZO TFT.

  6. Germanium and gallium

    International Nuclear Information System (INIS)

    Present article is devoted to germanium and gallium content in fluorite. The literature data on germanium and gallium content was analysed. The literature data on germanium and gallium distribution in fluorite of various geologic deposits and ores of Kazakhstan, Uzbekistan, Tajikistan and some geologic deposits of Russia were studied. The germanium and gallium content in fluorite of geologic deposits of various mineralogical and genetic type was defined.

  7. Automotive Aluminium Recycling

    Energy Technology Data Exchange (ETDEWEB)

    Gelas, B. des

    2000-07-01

    This paper aims at providing an overview on the contribution of aluminium recycling in the supply of new aluminium for automotive applications. Based on a presentation on how the global European automotive aluminium supply requirements are met, an analysis of the present and future contribution of automotive aluminium recycling is first presented. Current situation and future developments for automotive aluminium recycling practices are then commented, together with an outline on design principles for easier aluminium recycling. (orig.)

  8. Preparation of Amorphous Indium-gallium-zinc-oxide Film and Its Application in Thin-film Transistor%非晶铟镓锌氧化物薄膜的制备及其在薄膜晶体管中的应用

    Institute of Scientific and Technical Information of China (English)

    李光; 郑艳彬; 王文龙; 姜志刚

    2012-01-01

    Amorphous indium-gallium-zinc-oxide ( a-IGZO ) thin film, as a new kind of transparent oxide semiconductor material, has attracted much attention recently. This is due to its excellent performance and it has been successfully applied in thin-film transistors ( TFT) , showing great application prospection in display industry. In this presentation, the crystal structure of IGZO was also introduced. The main preparation methods of a-IGZO film were introduced and reviewed, including sputtering, spin-coating and inkjet printing. At last, we give some prospects on the industrialization of IGZO TFT-based display technology.%非晶铟镓锌氧化物(a-IGZO)薄膜,作为一种新型透明氧化物半导体材料,最近引起了广泛关注.这主要是由于它优异的性能可以使它作为薄膜晶体管的有源层材料,在显示行业有巨大的应用前景.本文首先介绍了铟镓锌氧化物的结构,同时综述了非晶铟镓锌氧化物薄膜的制备方法,包括溅射、悬涂和喷墨印刷技术;最后对基于铟镓锌氧化物薄膜晶体管背板技术的产业化进行了展望.

  9. Note on thermodynamic instability of M4C3-type carbides of gallium group metals

    International Nuclear Information System (INIS)

    The paper deals with thermodynamic stability of hypothetical solid binary M4C3 carbides of gallium, indium and thallium. Heats of formation whose contribution to the stability of these compounds is dominant, were estimated by two independent methods: semiempirical theory of Miedema and empirical trends in the heats of formation of nitrides and carbides of Group III elements. Entropies were calculated with the use of the Cantor equation. The estimated values suggest that M4C3 carbides of gallium, indium and thallium are thermodynamically unstable with regard to their decomposition of elements. (Author)

  10. Investigations in gallium removal

    Energy Technology Data Exchange (ETDEWEB)

    Philip, C.V.; Pitt, W.W. [Texas A and M Univ., College Station, TX (United States); Beard, C.A. [Amarillo National Resource Center for Plutonium, TX (United States)

    1997-11-01

    Gallium present in weapons plutonium must be removed before it can be used for the production of mixed-oxide (MOX) nuclear reactor fuel. The main goal of the preliminary studies conducted at Texas A and M University was to assist in the development of a thermal process to remove gallium from a gallium oxide/plutonium oxide matrix. This effort is being conducted in close consultation with the Los Alamos National Laboratory (LANL) personnel involved in the development of this process for the US Department of Energy (DOE). Simple experiments were performed on gallium oxide, and cerium-oxide/gallium-oxide mixtures, heated to temperatures ranging from 700--900 C in a reducing environment, and a method for collecting the gallium vapors under these conditions was demonstrated.

  11. Gallium scintigraphy for diagnosis of septic arthritis and osteomyelitis in children

    International Nuclear Information System (INIS)

    Thirty-four children with presumptive acute osteomyelitis or septic arthritis underwent early gallium-67 citrate scintigraphy and have been retrospectively reviewed. Diagnostic accuracy using this technique was 91%. Gallium-67 citrate is a more reliable radiopharmaceutical agent for the detection of selected acute musculoskeletal infections than either technetium methylene diphosphonate or indium-111. However, the radiation dosage from gallium is higher than from other radiopharmaceutical agents, and the authors would recommend its use only in cases where the diagnosis cannot be made on the basis of clinical, laboratory, or plain roentgenographic criteria

  12. Aluminium in human sweat.

    Science.gov (United States)

    Minshall, Clare; Nadal, Jodie; Exley, Christopher

    2014-01-01

    It is of burgeoning importance that the human body burden of aluminium is understood and is measured. There are surprisingly few data to describe human excretion of systemic aluminium and almost no reliable data which relate to aluminium in sweat. We have measured the aluminium content of sweat in 20 healthy volunteers following mild exercise. The concentration of aluminium ranged from 329 to 5329μg/L. These data equate to a daily excretion of between 234 and 7192μg aluminium and they strongly suggest that perspiration is the major route of excretion of systemic aluminium in humans.

  13. Aluminium structural elements

    OpenAIRE

    Švent, Nejc

    2016-01-01

    This thesis focuses on the structural analysis of aluminium structural members in accordance with the SIST EN 1999-1-1 standard. In the introduction, historical development of aluminium is summarized, as well as the processes of structural aluminium production and manufacture. Predominantly, resistance control checks of aluminium structural members are covered, with special attention to the major contrasts between aluminium and steel structural analyses. Finally, fundamental examples of resis...

  14. Sequential technetium-99m HMDP-gallium-67 citrate imaging for the evaluation of infection in the painful prosthesis

    International Nuclear Information System (INIS)

    In order to evaluate the clinical utility of sequential technetium-99m HMDP-gallium-67 scanning in patients with painful orthopedic prosthesis, a retrospective review was made of 154 sequential scans performed in 130 patients. Criteria for a positive study included spatially incongruent gallium-technetium uptake or gallium uptake that was congruent but more intense than technetium. Images were interpreted as negative if gallium was congruent and less intense than technetium. Sixty-six patients underwent surgery (31 infected, 35 aseptic), and 64 were evaluated clinically (3 infected, 61 aseptic). The combined results of the surgical and nonsurgical patients yielded a sensitivity of 66%, a specificity of 81%, and an accuracy of 77%. In this series, the technetium-gallium scan combination has proven to be helpful but more recent techniques such as indium-111-labeled leukocytes may prove to be superior to sequential technetium-gallium imaging

  15. The study of aluminium anodes for high power density AL-air batteries with brine electrolytes

    OpenAIRE

    Nestoridi, Maria

    2009-01-01

    In this thesis aluminium alloys containing small additions of both tin (~ 0.1 wt %) and gallium (~ 0.05 wt %) dissolve anodically at high rates in brine media; at room temperature, current densities > 0.2 A cm-2 can be obtained at potentials close to the open circuit potential, ~ -1.5 V vs SCE. Alloys without both tin and gallium do not dissolve at such a negative potential. The tin exists in the alloys as a second phase, typically as ~ 1 ?m inclusions throughout the aluminium structure. Anod...

  16. 原子层沉积氧化锌应用于铜铟镓硒太阳能电池缓冲层的研究%Study on Application of Atomic Layer Depositing Zinc Oxide for Buffer Layer to Copper Indium Gallium Selenium Solar Battery

    Institute of Scientific and Technical Information of China (English)

    廖荣; 张海燕; 谢佳亮; 杨铁铮; 罗文中; 胡伟

    2013-01-01

    A zinc oxide thin-film was deposited on soda lime glass with the method of atomic layer deposition (ALD),and field emission scanning electron microscope and X-ray diffractometer were employed to analyze the surface appearance and phase of the sample.The results show that the nanoparticle of ZnO is hexangular wurtzite structure and the size of particle is 30-60 nm.The measured thickness of ZnO thin-film is only 50 nm,which can meet the requirement of buffer layer.Transmittance of the thin-film in visible light area is more than 90%.Using atomic layer deposited zinc oxide thin-film as buffer layer of copper indium gallium selenium (CIGS) solar battery,it can be found that the zinc oxide layer covers the CIGS layer tightly,and that the photoelectric conversion efficiency of battery is high,so it can fully replace the toxic CdS as buffer layer.%用原子层沉积法在钠钙玻璃上沉积氧化锌薄膜,利用场发射扫描电镜和X射线衍射(XRD)等对样品表面形貌和物相进行分析,结果表明得到的ZnO纳米颗粒为六角纤锌矿结构,颗粒的尺寸在30~60 nm之间;测得的ZnO薄膜厚度仅50 nm,符合缓冲层要求;薄膜在可见光区域透射率达90%以上;使用原子层沉积氧化锌薄膜作铜铟镓硒太阳能电池的缓冲层,TEM显示氧化锌层完好、致密地覆盖在CIGS层上,电池的光电转换效率较高,完全可以替代有毒的CdS作缓冲层.

  17. Recovery of galium and indium from liquid crystal displays and CIGS photovailtaic modules

    NARCIS (Netherlands)

    Bisselink, R.; Steeghs, W.; Brouwer, J.G.H.

    2014-01-01

    Abstract: The increasing amount of electronics, such as consumer products and green technologies (e.g. solar PV cells) increases the demand of metals such as indium and gallium. This increasing demand together with the dependency on import of these metals drive research on recycling of waste electro

  18. Uranium and thorium behavior at aluminium floating-zone refining

    International Nuclear Information System (INIS)

    Uranium and thorium behaviour during aluminium refining by crystallization from the melt is ascertained. Measurements of of uranium and thorium radioactive impurities content in high-purity aluminiumn samples using the surface α-activity method are carried out. The content of the given impurities happened to be less than 1 x 10-7 mass.%. Such purity satisfies the requirements to materials applied in the low background 71Ge detection system of gallium-germanium solar neutrino detector

  19. Indium-111 leukocyte scintigraphic detection of subclinical osteomyelitis complicating delayed and nonunion long bone fractures: a prospective study

    International Nuclear Information System (INIS)

    Twenty patients were studied prospectively with indium-labeled leukocyte imaging to evaluate its effectiveness in differentiating noninfected delayed or nonunion from osteomyelitis complicating these entities. All patients underwent an open surgical procedure within 24 h of the scan. Bone specimens from the nonunion site were obtained for microbiological and histological analysis to confirm the presence or absence of osteomyelitis. In these twenty patients, the sensitivity of the indium scintigraphy was 100%, the specificity 100%, and the overall accuracy 100%. Indium-labeled leukocyte scintigraphy is significantly more accurate than /sup 99m/technetium and 67gallium imaging had been, when studied earlier, in detecting subclinical osteomyelitis complicating nonunion. Indium-labeled leukocyte scintigraphy should supplant sequential technetium and gallium studies in this patient population when the surgeon must determine whether subclinical osteomyelitis is complicating fracture management of delayed and nonunions

  20. NREL preprints for the 23rd IEEE Photovoltaic Specialists Conference

    Energy Technology Data Exchange (ETDEWEB)

    Fitzgerald, M. [ed.

    1993-05-01

    Topics covered include various aspects of solar cell fabrication and performance. Aluminium-gallium arsenides, cadmium telluride, amorphous silicon, and copper-indium-gallium selenides are all characterized in their applicability in solar cells.

  1. Electrodeposition of gallium for photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, Raghu N.

    2016-08-09

    An electroplating solution and method for producing an electroplating solution containing a gallium salt, an ionic compound and a solvent that results in a gallium thin film that can be deposited on a substrate.

  2. Sustainable Aluminium Systems

    Directory of Open Access Journals (Sweden)

    Sergio R. Ermolli

    2010-09-01

    Full Text Available In the present paper, an analytical presentation of some popular aluminium systems that contribute to sustainability of structures is presented. Special emphasis has been given to the properties of aluminium, while the influence of these systems in the overall performance of the structure regarding environment and economy is described. In particular, characteristics of aluminium elements such as high reflectivity and recyclability and their role in life cycle analysis (LCA are analyzed. The connections between energy efficiency and conservation of buildings and aluminium application are also discussed. Building applications such as curtain walls, window frames and facade sheets are presented and thoroughly investigated, considering their environmental and economic aspects. Furthermore, many innovative techniques that use aluminium elements in collaboration with other systems in order to produce renewable energy, such as solar panels and photovoltaics, are introduced. Finally, environmental innovations such as optimized ventilation mechanisms and light and shade management systems based on aluminium members are presented.

  3. Fabrication of Aluminum Gallium Nitride/Gallium Nitride MESFET And It's Applications in Biosensing

    Science.gov (United States)

    Alur, Siddharth

    Gallium Nitride has been researched extensively for the past three decades for its application in Light Emitting Diodes (LED's), power devices and UV photodetectors. With the recent developments in crystal growth technology and the ability to control the doping there has been an increased interest in heterostructures formed between Gallium nitride and it's alloy Aluminium Gallium Nitride. These heterostructures due to the combined effect of spontaneous and piezoelectric effect can form a high density and a high mobility electron gas channel without any intentional doping. This high density electron gas makes these heterostructures ideal to be used as sensors. Gallium Nitride is also chemically very stable. Detection of biomolecules in a fast and reliable manner is very important in the areas of food safety and medical research. For biomolecular detection it is paramount to have a robust binding of the probes on the sensor surface. Therefore, in this dissertation, the fabrication and application of the AlGaN/GaN heterostructures as biological sensors for the detection of DNA and Organophosphate hydrolase enzyme is discussed. In order to use these AlGaN/GaN heterostructures as biological sensors capable of working in a liquid environment photodefinable polydimethyl-siloxane is used as an encapsulant. The immobilization conditions for a robust binding of thiolated DNA and the catalytic receptor enzyme organophosphate hydrolase on gold surfaces is developed with the help of X-ray photoelectron spectroscopy. DNA and OPH are detected by measuring the change in the drain current of the device as a function of time.

  4. Chemical mechanical polishing of Indium phosphide, Gallium arsenide and Indium gallium arsenide films and related environment and safety aspects

    Science.gov (United States)

    Matovu, John Bogere

    As scaling continues with advanced technology nodes in the microelectronic industry to enhance device performance, the performance limits of the conventional substrate materials such as silicon as a channel material in the front-end-of-the-line of the complementary metal oxide semiconductor (CMOS) need to be surmounted. These challenges have invigorated research into new materials such as III-V materials consisting of InP, GaAs, InGaAs for n-channel CMOS and Ge for p-channels CMOS to enhance device performance. These III-V materials have higher electron mobility that is required for the n-channel while Ge has high hole mobility that is required for the p-channel. Integration of these materials in future devices requires chemical mechanical polishing (CMP) to achieve a smooth and planar surface to enable further processing. The CMP process of these materials has been associated with environment, health and safety (EH&S) issues due to the presence of P and As that can lead to the formation of toxic gaseous hydrides. The safe handling of As contaminated consumables and post-CMP slurry waste is essential. In this work, the chemical mechanical polishing of InP, GaAs and InGaAs films and the associated environment, health and safety (EH&S) issues are discussed. InP removal rates (RRs) and phosphine generation during the CMP of blanket InP films in hydrogen peroxide-based silica particle dispersions in the presence and absence of three different multifunctional chelating carboxylic acids, namely oxalic acid, tartaric acid, and citric acid are reported. The presence of these acids in the polishing slurry resulted in good InP removal rates (about 400 nm min-1) and very low phosphine generation (surfaces (0.1 nm RMS surface roughness). The optimized slurry compositions consisting of 3 wt % silica, 1 wt % hydrogen peroxide and 0.08 M oxalic acid or citric acid that provided the best results on blanket InP films were used to evaluate their planarization capability of patterned InP-STI structures of 200 mm diameter wafers. Cross sectional scanning electron microscope (SEM) images showed that InP in the shallow trench isolation structures was planarized and scratches, slurry particles and smearing of InP were absent. Additionally, wafers polished at pH 6 showed very low dishing values of about 12-15 nm, determined by cross sectional SEM. During the polishing of blanket GaAs, GaAs RRs were negligible with deionized water or with silica slurries alone. They were relatively high in aq. solutions of H2O2 alone and showed a strong pH dependence, with significantly higher RRs in the alkaline region. The addition of silica particles to aq. H2O2 did not increase the GaAs RRs significantly. The evolution of arsenic trihydride (AsH3) during the dissolution of GaAs in aq. H2O2 solution was similarly higher in the basic pH range than in neutral pH or in the acidic pH range. However, no AsH3 was measured during polishing, evidently because of the relatively high water solubility of AsH3. The work done on InGaAs polishing shows that InGaAs RR trends are different from those observed for InP or GaAs. InGaAs RRs at pH 2 are higher than those at pH 10 and highest at pH 4. Dissolution rates (DRs), Fourier Transform Infrared Spectroscopy (FTIR), contact angles, X-Ray Photoelectron Spectroscopy (XPS), X-Ray Fluorescence Spectroscopy (XRF), zeta potential measurements and calculated Gibbs free energy changes of the reactions involved during polishing and gas formation were used to discuss the observed RRs and hydride gas generation trends and to propose the reaction pathways involved in the material removal and in hydride gas generation mechanisms.

  5. Electrodeposition of indium

    Energy Technology Data Exchange (ETDEWEB)

    Fouda, A.S.; Ahmed, A.I.; Madkour, L.H.

    Metallic indium was deposited from aqueous solutions of indium trichloride containing also, acetate, thiocyanate, chloride, iodide, sulphate, oxalate, ethanol, acetamide and citrate of sodium or potassium. The optimum conditions are: pH 2-5, current density 2-25 mA cm/sup -2/, temperature 30/sup O/C and metal ion concentration O.2 mol l/sup -1/. Deposits have been obtained on a platinum sheet cathode. Chemical analysis reveals that the purity of the indium is better than 99%. The rate of deposition is also determined. 15 refs.

  6. High-Pressure Synthesis, Crystal Structure and Physical Properties of Gallium Oxonitride

    OpenAIRE

    Zvoriste, Carmen

    2011-01-01

    This thesis is concerned with the synthesis and properties of the high-pressure, high-temperature (HP/HT) phase of gallium oxonitride, which has a spinel-type structure. Since this material is an analogue of γ-alon (spinel-aluminium oxonitride), which is known to be an important material with a wide range of applications, the spinelstructured gallium oxonitride is an attractive material with the potential for tailoring its composition and tuning its electronic properties, i.e. for optoelectro...

  7. The Potentiostatic Electrodeposition of Indium doped Aluminium Selenide Thin Films

    Directory of Open Access Journals (Sweden)

    R.K. Pathak and Sipi Mohan

    2013-12-01

    Full Text Available The In containing AlSe thin films were electrosynthesized by electrochemical co-deposition technique. The morphological properties of thin films were studied through the Scanning Electron Micrograph (SEM while the structural features through X-Ray Diffraction technique (XRD. The deposition current along with the film thickness values, the charge carrier density, flat band potential, corrosion characteristics i.e., corrosion current, corrosion potential and corrosion rate were calculated.

  8. Rows of Dislocation Loops in Aluminium Irradiated by Aluminium Ions

    DEFF Research Database (Denmark)

    Henriksen, L.; Johansen, A.; Koch, J.;

    1967-01-01

    Single-crystal aluminium specimens, irradiated with 50-keV aluminium ions, contain dislocation loops that are arranged in regular rows along <110 > directions. ©1967 The American Institute of Physics......Single-crystal aluminium specimens, irradiated with 50-keV aluminium ions, contain dislocation loops that are arranged in regular rows along directions. ©1967 The American Institute of Physics...

  9. Micro and nano-structured green gallium indium nitride/gallium nitride light-emitting diodes

    Science.gov (United States)

    Stark, Christoph J. M.

    Light-emitting diodes (LEDs) are commonly designed and studied based on bulk material properties. In this thesis different approaches based on patterns in the nano and micrometer length scale range are used to tackle low efficiency in the green spectral region, which is known as “green gap”. Since light generation and extraction are governed by microscopic processes, it is instructive to study LEDs with lateral mesa sizes scaled to the nanometer range. Besides the well-known case of the quantum size effect along the growth direction, a continuous lateral scaling could reveal the mechanisms behind the purported absence of a green gap in nanowire LEDs and the role of their extraction enhancement. Furthermore the possibility to modulate strain and piezoelectric polarization by post growth patterning is of practical interest, because the internal electric fields in conventional wurtzite GaN LEDs cause performance problems. A possible alternative is cubic phase GaN, which is free of built-in polarization fields. LEDs on cubic GaN could show the link between strong polarization fields and efficiency roll-off at high current densities, also known as droop. An additional problem for all nitride-based LEDs is efficient light extraction. For a planar GaN LED only roughly 8% of the generated light can be extracted. Novel lightextraction structures with extraction-favoring geometry can yield significant increase in light output power. To investigate the effect of scaling the mesa dimension, micro and nano-sized LED arrays of variable structure size were fabricated. The nano-LEDs were patterned by electron beam lithography and dry etching. They contained up to 100 parallel nano-stripe LEDs connected to one common contact area. The mesa width was varied over 1 μm, 200 nm, and 50 nm. These LEDs were characterized electrically and optically, and the peak emission wavelength was found to depend on the lateral structure size. An electroluminescence (EL) wavelength shift of 3 nm towards smaller values was observed when the stripe width was reduced from 1 μm to 50 nm. At the same time a strong fourfold enhancement of the light emission from the patterned region over the unpatterned area was observed. Micro-patterned LEDs showed non-linear scaling of the light output power, and an enhancement of 39 % was achieved for structures with an area fill ratio of 0.5 over an LED with square mesa. Growth of cubic GaN and cubic GaInN/GaN LEDs was shown by M-OVPE in Vshaped grooves formed by the {111} planes of etched silicon. SEM images of the GaN layer in small ( 0.5 μm) regions show a contrast change where the phase boundary between cubic and wurtzite GaN is expected to occur. The growth parameter space is explored for optimal conditions while minimizing the alloying problem for GaN growth on Si. The cubic GaN phase is confirmed by electron back-scatter diffraction (EBSD) in the V-groove center, whereas wurtzite GaN is found near the groove edges. Luminescence of undoped GaN and GaInN/GaN multi-quantum well structures was studied by cathodoluminescence (CL). The undoped cubic GaN structure showed strong band-edge luminescence at 385 nm (3.22 eV) at 78 K, whereas for the MQW device strong emission at 498 nm is observed, even at room temperature. Full cubic LED structures were grown, and wavelength-stable electroluminescence at 489 nm was demonstrated. LEDs with integrated light extraction structures are grown on free-standing GaN substrates with different off-cut angles. The devices with different off-cut show pronounced features at the top surface that also penetrate the active region. For a 2.24° off-cut, these features resemble fish scales, where the feature sizes are in the μm-range. The 2.24° off-cut LED shows a 3.6-fold increased light output power compared to a LED on virtually on-axis substrate with 0.06° off-cut. The enhancement found in the fish scale LEDs is attributed to increased light scattering, effectively reducing the fraction of trapped light. These results show the potential of structures on the micro and nanometer scale

  10. Electroreflectance of indium gallium arsenide phosphide lattice matched to indium phosphide

    International Nuclear Information System (INIS)

    We report the first systematic measurement of the electroreflectance spectra of In/sub u/Ga/sub 1-u/P/sub v/As/sub 1-v/ over the range of compositions that lattice-match InP substrates, at room temperature and for energies between 0.7 and 3.5 eV. Analysis of the spectra has enabled us to determine the composition dependence of E0, E0+Δ0, E1, E1+Δ1, Δ0, and Δ1. Experimentally determined values of E0, E0+Δ0, and m*/m0 have been used to predict the values of the g factors for these compounds

  11. Recovery in aluminium

    DEFF Research Database (Denmark)

    Gundlach, Carsten

    2006-01-01

    In the present thesis the development of a unique experimental method for volume characterisation of individual embedded crystallites down to a radius of 150 nm is presented. This method is applied to in-situ studies of recovery in aluminium. The method is an extension of 3DXRD microscopy, an X...... are represented as strings. To identify the strings a combination of a 5D connected component type algorithm and multi-peak fitting was found to be superior. The first use of the method was a study of recovery of a deformed aluminium alloy (AA1050). The aluminium alloy was deformed by cold rolling to a thickness...

  12. 铟镓砷焦平面阵列在微光夜视应用中的潜力及前景%The Potential and Prospect of Indium Gallium Arsenide Focal Plane Array Applied to Low Light Level Night Vision

    Institute of Scientific and Technical Information of China (English)

    潘京生; 孙建宁; 金戈; 任玲; 毛汉祺; 顾燕; 郭一亮; 苏德坦

    2014-01-01

    得益于夜气辉在短波红外(SWIR)0.9~1.7μm波段的自然辐射数十倍强于夜天空在可见光和近红外(NIR)0.4~0.9μm波段的辐射,SWIR成像成为应用于微光条件下的成像探测的最佳选择,由晶格匹配In0.53Ga0.47As/InP制作InGaAs焦平面阵列(Focal Plane Array,FPA),灵敏于0.9~1.7μm波段,在整个响应波段具有超过70%的量子效率,和室温非制冷工作的极低的暗电流。通过减薄基底,还可将InGaAs FPA的短波限延伸至可见光波段的0.4μm。最近几年,超低暗电流、低读出噪声、大面阵和小像素尺寸的InGaAs FPA的开发取得了实质性的进展,特别是暗电流得到了数量级的降低,InGaAs FPA探测器已经显露出应用于微光夜视的极大潜力,并且还通过采用更复杂的温度相关的非均匀校正算法实现了无TEC的低功耗工作,基于超低噪声的密集阵列InGaAs FPA的SWIR成像技术有望成为新一代夜视技术的一个重要组成部份。%The shortwave infrared(SWIR)spectral irradiance in the 0.9μm to 1.7μm band which caused by night airglow is several ten times stronger than the irradiance in the visible and near infrared realm of 0.4μm to 0.9μm of the night sky, so SWIR imaging is the best choice for the imaging detection under low light level condition. The Indium Gallium Arsenide(InGaAs)focal plane array(FPA)sensors based on lattice matched In0.53Ga0.47As/InP is sensitive to SWIR light whose wavelength is from 0.9μm to 1.7μm, matching the spectral irradiance caused by night airglow, and have exceeded quantum efficiency of 70%over whole response spectral range, as well as with very low dark current while working at room temperature. Removing the InP substrate from the FPA allows extending cutoff wavelength to visible region of 0.4μm. The work on InGaAs FPA with ultra low dark current, low readout noise, large format and small pixel size has been progressing substantially in

  13. Optical properties of aluminium-gallium-nitride semiconductors; Optische Eigenschaften von Aluminium-Galliumnitrid-Halbleitern

    Energy Technology Data Exchange (ETDEWEB)

    Roeppischer, Marcus

    2011-08-17

    In this work fundamental optical properties of AlN, GaN and their alloys are presented. Spectroscopic ellipsometry from the near infrared (NIR) to the vacuum-ultraviolet (VUV) spectral region was the main tool to investigate these properties. The complete dielectric function (DF) of cubic as well as hexagonal GaN and AlN in the range between 0.6 eV and 20 eV is shown here, for the first time. A layer model including surface roughness and buffer layers was used to separate the DF of the investigated layer from the measured pseudo-DF. Afterwards all absorption structures in the DF's are discussed in detail. Due to the comparison with calculated bandstructures these absorption structures could be connected to interband transitions at high symmetry points in the Brillouin zone (BZ). Within this analysis similarities and differences between GaN and AlN are discussed. For zincblende (zb) AlN a pronounced absorption tail below the direct band gap transition was detected. This behaviour is typical for a phonon-assisted indirect absorption. In contrast zb-GaN exhibits a clear direct absorption. Furthermore, a change in the energetic position of the two main interband absorptions E1 and E2 at the L- and X-point of the BZ was found. A detailed analysis of the anisotropic fundamental band gap of hexagonal AlN offers a interchange of the two topmost valance bands at the BZ center compared to GaN. Due to this permutation the fundamental band edge of wurtzit (wz) AlN is only visible for parallel polarized light, while for GaN it can be detect in the perpendicular configuration. By analysing the energetic position of the three excitonic transitions the crystal-field- and spin-orbit-splitting were defined to be {delta}{sub cr}=-226 meV and {delta}{sub so}=14 meV. In addition, the energetic positions for these transitions at T=15 K are 6.0465 eV, 6.2694 eV and 6.2775 eV. The comparison between measurements at room and low temperature shows an energetic shift for both absorption edges of about 80 meV. By comparing the energetic positions of the excitonic transitions with the lattice parameters of different samples on silicon, sapphire and SiC substrate the influence of strain on the optical properties of wz-AlN was investigated. Due to this analysis the deformation potentials within the cubic approximation were calculated. Finally the spectral region below the fundamental band gap absorption of cubic AlGaN layers were studied. Therefore an analytical model was developed to calculate the dispersion in the transparent range for an arbitrary Al-content.

  14. Field-effect transistors based on cubic indium nitride.

    Science.gov (United States)

    Oseki, Masaaki; Okubo, Kana; Kobayashi, Atsushi; Ohta, Jitsuo; Fujioka, Hiroshi

    2014-02-04

    Although the demand for high-speed telecommunications has increased in recent years, the performance of transistors fabricated with traditional semiconductors such as silicon, gallium arsenide, and gallium nitride have reached their physical performance limits. Therefore, new materials with high carrier velocities should be sought for the fabrication of next-generation, ultra-high-speed transistors. Indium nitride (InN) has attracted much attention for this purpose because of its high electron drift velocity under a high electric field. Thick InN films have been applied to the fabrication of field-effect transistors (FETs), but the performance of the thick InN transistors was discouraging, with no clear linear-saturation output characteristics and poor on/off current ratios. Here, we report the epitaxial deposition of ultrathin cubic InN on insulating oxide yttria-stabilized zirconia substrates and the first demonstration of ultrathin-InN-based FETs. The devices exhibit high on/off ratios and low off-current densities because of the high quality top and bottom interfaces between the ultrathin cubic InN and oxide insulators. This first demonstration of FETs using a ultrathin cubic indium nitride semiconductor will thus pave the way for the development of next-generation high-speed electronics.

  15. Gallium--A smart metal

    Science.gov (United States)

    Foley, Nora; Jaskula, Brian W.

    2013-01-01

    Gallium is a soft, silvery metallic element with an atomic number of 31 and the chemical symbol Ga. The French chemist Paul-Emile Lecoq de Boisbaudran discovered gallium in sphalerite (a zinc-sulfide mineral) in 1875 using spectroscopy. He named the element "gallia" after his native land of France (formerly Gaul; in Latin, Gallia). The existence of gallium had been predicted in 1871 by Dmitri Mendeleev, the Russian chemist who published the first periodic table of the elements. Mendeleev noted a gap in his table and named the missing element "eka-aluminum" because he determined that its location was one place away from aluminum in the table. Mendeleev thought that the missing element (gallium) would be very much like aluminum in its chemical properties, and he was right. Solid gallium has a low melting temperature (~29 degrees Celsius, or °C) and an unusually high boiling point (~2,204 °C). Because of these properties, the earliest uses of gallium were in high-temperature thermometers and in designing metal alloys that melt easily. The development of a gallium-based direct band-gap semiconductor in the 1960s led to what is now one of the most well-known applications for gallium-based products--the manufacture of smartphones and data-centric networks.

  16. Extraction of indium from indium-zinc concentrates

    Institute of Scientific and Technical Information of China (English)

    LI Shi-qing; TANG Mo-tang; HE Jing; YANG Sheng-hai; TANG Chao-bo; CHEN Yong-ming

    2006-01-01

    A new process for extracting indium from indium-zinc concentrates was proposed. The process can directly extract indium from removed copper solution by D2EHPA, and cancel the stage of removing iron in the traditional process because of using iron and part of zinc in the In-Zn concentrates for direct preparing high quality Mn-Zn soft magnetic ferrites. The technologies in the processes, such as leaching the neutral leached residues with high concentrated acid at high temperature, reduction ferric and removing copper, and extracting indium, were investigated. The results show that total recovery ratio of indium is increased from less than 70% in the traditional process to more than 95%. This process has the advantages of largely simplifying the procedure of indium extraction, zero draining off of iron residue and zero emitting of SO2. So this is a clean production process.

  17. Indium Sorption to Iron Oxides

    Science.gov (United States)

    White, S. J.; Sacco, S. A.; Hemond, H.; Hussain, F. A.; Runkel, R. L.; Walton-Day, K. E.; Kimball, B. A.; Shine, J. P.

    2014-12-01

    Indium is an increasingly important metal in semiconductors and electronics, and its use is growing rapidly as a semiconductive coating (as indium tin oxide) for liquid crystal displays (LCDs) and flat panel displays. It also has uses in important energy technologies such as light emitting diodes (LEDs) and photovoltaic cells. Despite its rapid increase in use, very little is known about the environmental behavior of indium, and concerns are being raised over the potential health effects of this emerging metal contaminant. One source of indium to the environment is acid mine drainage from the mining of lead, zinc, and copper sulfides. In our previous studies of a stream in Colorado influenced by acid mine drainage from lead and zinc mining activities, indium concentrations were found to be 10,000 times those found in uncontaminated rivers. However, the speciation and mobility of indium could not be reliably modeled because sorption constants to environmental sorbents have not been determined. In this study, we generate sorption constants for indium to ferrihydrite in the laboratory over a range of pHs, sorbent to sorbate ratios, and ionic strengths. Ferrihydrite is one of the most important sorbents in natural systems, and sorption to amorphous iron oxides such as ferrihydrite is thought to be one of the main removal mechanisms of metals from the dissolved phase in aqueous environments. Because of its relatively low solubility, we also find that indium hydroxide precipitation can dominate indium's partitioning at micromolar concentrations of indium. This precipitation may be important in describing indium's behavior in our study stream in Colorado, where modeling sorption to iron-oxides does not explain the complete removal of indium from the dissolved phase when the pH of the system is artificially raised to above 8. This study contributes much-needed data about indium's aqueous behavior, in order to better understand its fate, transport, and impacts in the

  18. Fatal aluminium phosphide poisoning

    Directory of Open Access Journals (Sweden)

    Meena Mahesh Chand

    2015-06-01

    Full Text Available Aluminium phosphide (AlP is a cheap solid fumigant and a highly toxic pesticide which is commonly used for grain preservation. AlP has currently aroused interest with a rising number of cases in the past four decades due to increased use for agricultural and non-agricultural purposes. Its easy availability in the markets has increased also its misuse for committing suicide. Phosphine inhibits cellular oxygen utilization and can induce lipid peroxidation. Poisoning with AlP has often occurred in attempts to commit suicide, and that more often in adults than in teenagers. This is a case of suicidal consumption of aluminium phosphide by a 32-year-old young medical anesthetist. Toxicological analyses detected aluminium phosphide. We believe that free access of celphos tablets in grain markets should be prohibited by law.

  19. Gallium interstitial contributions to diffusion in gallium arsenide

    Directory of Open Access Journals (Sweden)

    Joseph T. Schick

    2011-09-01

    Full Text Available A new diffusion path is identified for gallium interstitials, which involves lower barriers than the barriers for previously identified diffusion paths [K. Levasseur-Smith and N. Mousseau, J. Appl. Phys. 103, 113502 (2008, P. A. Schultz and O. A. von Lilienfeld, Modelling and Simulation in Materials Science and Engineering 17, 084007 (2009] for the charge states which dominate diffusion over most of the available range of Fermi energies. This path passes through the ⟨110⟩ gallium-gallium split interstitial configuration, and has a particularly low diffusion barrier of 0.35 eV for diffusion in the neutral charge state. As a part of this work, the character of the charge states for the gallium interstitials which are most important for diffusion is investigated, and it is shown that the last electron bound to the neutral interstitial occupies a shallow hydrogenic bound state composed of conduction band states for the hexagonal interstitial and both tetrahedral interstitials. How to properly account for the contributions of such interstitials is discussed for density-functional calculations with a k-point mesh not including the conduction band edge point. Diffusion barriers for gallium interstitials are calculated in all the charge states which can be important for a Fermi level anywhere in the gap, q = 0, +1, +2, and +3, for diffusion via the ⟨110⟩ gallium-gallium split interstitial configuration and via the hexagonal interstitial configuration. The lowest activation enthalpies over most of the available range of Fermi energies are found to correspond to diffusion in the neutral or singly positive state via the ⟨110⟩ gallium-gallium split interstitial configuration. It is shown that several different charge states and diffusion paths contribute significantly for Fermi levels within 0.2 eV above the valence band edge, which may help to explain some of the difficulties [H. Bracht and S. Brotzmann, Phys. Rev. B 71, 115216 (2005] which

  20. Fire exposed aluminium structures

    NARCIS (Netherlands)

    Maljaars, J.; Fellinger, J.H.H.; Soetens, F.

    2006-01-01

    Material properties and mechanical response models for fire design of steel structures are based on extensive research and experience. Contrarily, the behaviour of aluminium load bearing structures exposed to fire is relatively unexplored. This article gives an overview of physical and mechanical pr

  1. Gallium Safety in the Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Cadwallader, L.C.

    2003-05-07

    A university laboratory experiment for the US Department of Energy magnetic fusion research program required a simulant for liquid lithium. The simulant choices were narrowed to liquid gallium and galinstan (Ga-In-Sn) alloy. Safety information on liquid gallium and galinstan were compiled, and the choice was made to use galinstan. A laboratory safety walkthrough was performed in the fall of 2002 to support the galinstan experiment. The experiment has been operating successfully since early 2002.

  2. Gallium Safety in the Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Lee C. Cadwallader

    2003-06-01

    A university laboratory experiment for the US Department of Energy magnetic fusion research program required a simulant for liquid lithium. The simulant choices were narrowed to liquid gallium and galinstan (Ga-In-Sn) alloy. Safety information on liquid gallium and galinstan were compiled, and the choice was made to use galinstan. A laboratory safety walkthrough was performed in the fall of 2002 to support the galinstan experiment. The experiment has been operating successfully since early 2002.

  3. Gallium Safety in the Laboratory

    International Nuclear Information System (INIS)

    A university laboratory experiment for the US Department of Energy magnetic fusion research program required a simulant for liquid lithium. The simulant choices were narrowed to liquid gallium and galinstan (Ga-In-Sn) alloy. Safety information on liquid gallium and galinstan were compiled, and the choice was made to use galinstan. A laboratory safety walkthrough was performed in the fall of 2002 to support the galinstan experiment. The experiment has been operating successfully since early 2002

  4. Anelasticity of polycrystalline indium

    Energy Technology Data Exchange (ETDEWEB)

    Sapozhnikov, K., E-mail: k.sapozhnikov@mail.ioffe.ru [A.F.Ioffe Physical-Technical Institute, Politekhnicheskaya 26, 194021 St. Petersburg (Russian Federation); Golyandin, S. [A.F.Ioffe Physical-Technical Institute, Politekhnicheskaya 26, 194021 St. Petersburg (Russian Federation); Kustov, S. [Dept. de Fisica, Universitat de les Illes Balears, Cra Valldemossa km 7.5, E 07122 Palma de Mallorca (Spain)

    2009-09-15

    Mechanisms of anelasticity of polycrystalline indium have been studied over wide ranges of temperature (7-320 K) and strain amplitude (2 x 10{sup -7}-3.5 x 10{sup -4}). Measurements of the internal friction and Young's modulus have been performed by means of the piezoelectric resonant composite oscillator technique using longitudinal oscillations at frequencies of about 100 kHz. The stages of the strain amplitude dependence of the internal friction and Young's modulus defect, which can be attributed to dislocation - point defect and dislocation - dislocation interactions, have been revealed. It has been shown that thermal cycling gives rise to microplastic straining of polycrystalline indium due to the anisotropy of thermal expansion and to appearance of a 'recrystallization' internal friction maximum in the temperature spectra of amplitude-dependent anelasticity. The temperature range characterized by formation of Cottrell's atmospheres of point defects around dislocations has been determined from the acoustic data.

  5. Recycling process for recovery of gallium from GaN an e-waste of LED industry through ball milling, annealing and leaching

    International Nuclear Information System (INIS)

    Waste dust generated during manufacturing of LED contains significant amounts of gallium and indium, needs suitable treatment and can be an important resource for recovery. The LED industry waste dust contains primarily gallium as GaN. Leaching followed by purification technology is the green and clean technology. To develop treatment and recycling technology of these GaN bearing e-waste, leaching is the primary stage. In our current investigation possible process for treatment and quantitative leaching of gallium and indium from the GaN bearing e-waste or waste of LED industry dust has been developed. To recycle the waste and quantitative leaching of gallium, two different process flow sheets have been proposed. In one, process first the GaN of the waste the LED industry dust was leached at the optimum condition. Subsequently, the leach residue was mixed with Na2CO3, ball milled followed by annealing, again leached to recover gallium. In the second process, the waste LED industry dust was mixed with Na2CO3, after ball milling and annealing, followed acidic leaching. Without pretreatment, the gallium leaching was only 4.91 w/w % using 4 M HCl, 100 °C and pulp density of 20 g/L. After mechano-chemical processing, both these processes achieved 73.68 w/w % of gallium leaching at their optimum condition. The developed process can treat and recycle any e-waste containing GaN through ball milling, annealing and leaching. - Highlights: • Simplest process for treatment of GaN an LED industry waste developed. • The process developed recovers gallium from waste LED waste dust. • Thermal analysis and phase properties of GaN to Ga2O3 and GaN to NaGaO2 revealed. • Solid-state chemistry involved in this process reported. • Quantitative leaching of the GaN was achieved

  6. Electron microscopy of gallium nitride growth on polycrystalline diamond

    International Nuclear Information System (INIS)

    Transmission and scanning electron microscopy were used to examine the growth of gallium nitride (GaN) on polycrystalline diamond substrates grown by metalorganic vapour phase epitaxy with a low-temperature aluminium nitride (AlN) nucleation layer. Growth on unmasked substrates was in the (0001) orientation with threading dislocation densities ≈7 × 109 cm−2. An epitaxial layer overgrowth technique was used to reduce the dislocation densities further, by depositing silicon nitride stripes on the surface and etching the unmasked regions down to the diamond substrate. A re-growth was then performed on the exposed side walls of the original GaN growth, reducing the threading dislocation density in the overgrown regions by two orders of magnitude. The resulting microstructures and the mechanisms of dislocation reduction are discussed. (paper)

  7. Recovery in aluminium

    OpenAIRE

    Gundlach, Carsten

    2006-01-01

    In the present thesis the development of a unique experimental method for volume characterisation of individual embedded crystallites down to a radius of 150 nm is presented. This method is applied to in-situ studies of recovery in aluminium. The method is an extension of 3DXRD microscopy, an X-ray diffraction technique for studies of the evolution of grains within polycrystalline materials. The much smaller volume of the crystallites of interest here in comparison to grains implies that the ...

  8. Gallium scanning in cerebral and cranial infections

    International Nuclear Information System (INIS)

    Eighteen patients with cranial or intracranial infections were studied with technetium and gallium brain scans. Seven of 18 lesions were noted with gallium and not with pertechnetate, while the reverse pattern was not seen. Brain abscesses were visualized with gallium but not with pertechnetate in two of five cases. Osteomyelitis of the skull and mastoiditis showed intense gallium uptake in all cases, while meningitis or cerebritis gave inconsistent results

  9. Aluminium and human breast diseases.

    Science.gov (United States)

    Darbre, P D; Pugazhendhi, D; Mannello, F

    2011-11-01

    The human breast is exposed to aluminium from many sources including diet and personal care products, but dermal application of aluminium-based antiperspirant salts provides a local long-term source of exposure. Recent measurements have shown that aluminium is present in both tissue and fat of the human breast but at levels which vary both between breasts and between tissue samples from the same breast. We have recently found increased levels of aluminium in noninvasively collected nipple aspirate fluids taken from breast cancer patients (mean 268 ± 28 μg/l) compared with control healthy subjects (mean 131 ± 10 μg/l) providing evidence of raised aluminium levels in the breast microenvironment when cancer is present. The measurement of higher levels of aluminium in type I human breast cyst fluids (median 150 μg/l) compared with human serum (median 6 μg/l) or human milk (median 25 μg/l) warrants further investigation into any possible role of aluminium in development of this benign breast disease. Emerging evidence for aluminium in several breast structures now requires biomarkers of aluminium action in order to ascertain whether the presence of aluminium has any biological impact. To this end, we report raised levels of proteins that modulate iron homeostasis (ferritin, transferrin) in parallel with raised aluminium in nipple aspirate fluids in vivo, and we report overexpression of mRNA for several S100 calcium binding proteins following long-term exposure of MCF-7 human breast cancer cells in vitro to aluminium chlorhydrate. PMID:22099158

  10. Laser welding of aluminium alloys

    OpenAIRE

    Forsman, Tomas

    2000-01-01

    This thesis treats laser welding of aluminium alloys from a practical perspective with elements of mathematical analysis. The theoretical work has in all cases been verified experimentally. The aluminium alloys studied are from the 5xxx and 6xxx groups which are common for example in the automotive industry. Aluminium has many unique physical properties. The properties which more than others have been shown to influence the welding process is its high reflection, high thermal conductivity, lo...

  11. Method of aluminium fluoride manufacture

    International Nuclear Information System (INIS)

    The manufacture of aluminium fluoride is based on waste processing in uranium hexafluoride conversion to uranium oxides within the fuel cycle. The conversion is the stoichiometric conversion of uranium hexafluoride with aluminium nitrate to uranyl nitrate. This is extracted from the water phase by phosphoric acid trialkyl ester to an organic solvent and further processed. The discharge water phase is solidified by evaporation to solid aluminium fluoride and nitric acid. (M.S.)

  12. Gas sensitivity of indium oxide

    Institute of Scientific and Technical Information of China (English)

    HUANG Shi-zhen; LIN Wei; CHEN Wen-zhe

    2009-01-01

    The yellow indium oxide nanoparticles were prepared by sintering the white deposition at 500 ℃. The crystalline indium chloride and ammonia were used as the starting material. The results show that, by analyzing the particles through X-ray diffraction and TEM, the particles are very small, spherical, and the particle size is about 40 nm. The direct-heat components made from indium oxide in Cl2 and NO2 was tested respectively, the component is far more sensitive to NO2 than to Cl2 at low heating temperature, and the status is reversed at high heating temperature.

  13. Vacancy-indium clusters in implanted germanium

    KAUST Repository

    Chroneos, Alexander I.

    2010-04-01

    Secondary ion mass spectroscopy measurements of heavily indium doped germanium samples revealed that a significant proportion of the indium dose is immobile. Using electronic structure calculations we address the possibility of indium clustering with point defects by predicting the stability of indium-vacancy clusters, InnVm. We find that the formation of large clusters is energetically favorable, which can explain the immobility of the indium ions. © 2010 Elsevier B.V. All rights reserved.

  14. Self-assembly surface modified indium-tin oxide anodes for single-layer light-emitting diodes

    CERN Document Server

    Morgado, J; Charas, A; Matos, M; Alcacer, L; Cacialli, F

    2003-01-01

    We study the effect of indium-tin oxide surface modification by self assembling of highly polar molecules on the performance of single-layer light-emitting diodes (LEDs) fabricated with polyfluorene blends and aluminium cathodes. We find that the efficiency and light-output of such LEDs is comparable to, and sometimes better than, the values obtained for LEDs incorporating a hole injection layer of poly(3,4-ethylene dioxythiophene) doped with polystyrene sulphonic acid. This effect is attributed to the dipole-induced work function modification of indium-tin oxide.

  15. Medical Applications and Toxicities of Gallium Compounds

    Directory of Open Access Journals (Sweden)

    Christopher R. Chitambar

    2010-05-01

    Full Text Available Over the past two to three decades, gallium compounds have gained importance in the fields of medicine and electronics. In clinical medicine, radioactive gallium and stable gallium nitrate are used as diagnostic and therapeutic agents in cancer and disorders of calcium and bone metabolism. In addition, gallium compounds have displayed anti-inflammatory and immunosuppressive activity in animal models of human disease while more recent studies have shown that gallium compounds may function as antimicrobial agents against certain pathogens. In a totally different realm, the chemical properties of gallium arsenide have led to its use in the semiconductor industry. Gallium compounds, whether used medically or in the electronics field, have toxicities. Patients receiving gallium nitrate for the treatment of various diseases may benefit from such therapy, but knowledge of the therapeutic index of this drug is necessary to avoid clinical toxicities. Animals exposed to gallium arsenide display toxicities in certain organ systems suggesting that environmental risks may exist for individuals exposed to this compound in the workplace. Although the arsenic moiety of gallium arsenide appears to be mainly responsible for its pulmonary toxicity, gallium may contribute to some of the detrimental effects in other organs. The use of older and newer gallium compounds in clinical medicine may be advanced by a better understanding of their mechanisms of action, drug resistance, pharmacology, and side-effects. This review will discuss the medical applications of gallium and its mechanisms of action, the newer gallium compounds and future directions for development, and the toxicities of gallium compounds in current use.

  16. Gallium scintigraphy in Hansen's disease

    International Nuclear Information System (INIS)

    Gallium 67 imaging was used in 12 patients with documented Hansen's disease undergoing treatment or not in an attempt to determine the pattern of the disease. Diagnosis was confirmed by histopathology in all patients. The Mitsuda reaction was seen in all patients. Specific nuclear studies were performed when needed to evaluate particular organs better. Gallium 67 images show homogeneous, diffuse and moderate accumulation over the entire skin surface (except for the face) of untreated patients with multibacillary disease. The face skin in these cases presented homogeneous, diffuse but very marked uptake of gallium. Internal organ involvement was variable. There was a very good correlation among clinical, scintigraphical, immunological and histopathological data. The pattern of the body skin ('skin outlining') and face skin ('beard distribution') may be distinct for untreated patients with multibacillary leprosy. (orig.)

  17. First Principles Study of Aluminium Vacancy in Wurtzite Aluminium Nitride

    Institute of Scientific and Technical Information of China (English)

    GAO Ting-Ge; YI Jue-Min; ZHOU Zi-Yao; HU Xiao-Dong

    2008-01-01

    @@ We report that the aluminium vacancy in wurtzite AIN brings about two impurity levels e and a2 in the band gap, not just one single t2 level The aluminium vacancy carries a magnetic moment of 1 μB in the ground state. The molecule orbit of the aluminium vacancy becomes e↑↑ a2↑ rather than e↑↑ a2↑. The calculation is carried out by using the CASTEP code. The intrinsic symmetry of wurtzite A1N is the driving force for this spin splitting. Finally the symmetry of wurtzite AlN results in an anti-ferromagnetic coupling between the aluminium vacancies, as is predicted. Our findings are helpful to gain a more through understanding of the structural and spin property of aluminium vacancy in wurtzite AIN.

  18. The gallium solar neutrino experiment

    International Nuclear Information System (INIS)

    The overwhelming majority of solar neutrinos are low energy pp-neutrinos. Among the few potential experiments for their detection, the radiochemical Gallium Solar Neutrino experiment is the only one which has been demonstrated to be feasible. The strong motivations for performing such an experiment, the experimental approach, the major results of the pilot experiment performed in an international collaboration, recent progress in further reducing the counter backgrounds, experiments towards Resonance Ionization of Gallium for ultimate background reduction, the status of the project, and the plans for the future are all described. (author)

  19. Fatigue tests on aluminium bridges

    NARCIS (Netherlands)

    Maljaars, J.; Soetens, F.; Straalen, IJ.J. van

    2005-01-01

    Traffic bridges are subjected to variable loads and should therefore be checked on fatigue. Especially low weight materials, like aluminium, are sensitive to fatigue, because the variable load is a substantial part of the total load. This paper shows the structural design of an aluminium bridge load

  20. Fatigue tests on aluminium bridges

    NARCIS (Netherlands)

    Maljaars, J.; Soetens, F.; Straalen, IJ.J. van

    2004-01-01

    Traffic bridges are subjected to variable loads and should therefore be checked on fatigue. Especially low weight materials, like aluminium, are sensitive to fatigue, because the variable load is a substantial part of the total load. This paper shows the structural design of an aluminium bridge load

  1. Liquid gallium rotary electric contract

    Science.gov (United States)

    Przybyszewski, J. S.

    1969-01-01

    Due to its low vapor pressure, gallium, when substituted for mercury in a liquid slip ring system, transmits substantial amounts of electrical current to rotating components in an ultrahigh vacuum. It features low electrical loss, little or no wear, and long maintenance-free life.

  2. Common features of gallium perovskites

    NARCIS (Netherlands)

    Aleksiyko, R; Berkowski, M; Byszewski, P; Dabrowski, B; Diduszko, R; Fink-Finowicki, J; Vasylechko, LO

    2001-01-01

    The Czochralski and floating zone methods have been used to grow single crystals of gallium perovskites solid solutions with rare earth elements La, Pr, Nd, Sm and with Sr. The structure of the crystals has been investigated by powder X-ray, synchrotron radiation and neutron diffraction methods over

  3. Gallium scintigraphy in acute panniculitis

    International Nuclear Information System (INIS)

    Gallium scintigraphy was performed in a 27-yr-old female in search of a possible occult focus of infection; it showed an unusual diffuse superficial accumulation in the thighs and buttocks. Biopsy of an area of abnormal uptake showed lobular panniculitis which, in the clinical context, led to the diagnosis of Weber-Christian syndrome

  4. Gallium nitride electronics

    Science.gov (United States)

    Rajan, Siddharth; Jena, Debdeep

    2013-07-01

    In the past two decades, there has been increasing research and industrial activity in the area of gallium nitride (GaN) electronics, stimulated first by the successful demonstration of GaN LEDs. While the promise of wide band gap semiconductors for power electronics was recognized many years before this by one of the contributors to this issue (J Baliga), the success in the area of LEDs acted as a catalyst. It set the field of GaN electronics in motion, and today the technology is improving the performance of several applications including RF cell phone base stations and military radar. GaN could also play a very important role in reducing worldwide energy consumption by enabling high efficiency compact power converters operating at high voltages and lower frequencies. While GaN electronics is a rapidly evolving area with active research worldwide, this special issue provides an opportunity to capture some of the great advances that have been made in the last 15 years. The issue begins with a section on epitaxy and processing, followed by an overview of high-frequency HEMTs, which have been the most commercially successful application of III-nitride electronics to date. This is followed by review and research articles on power-switching transistors, which are currently of great interest to the III-nitride community. A section of this issue is devoted to the reliability of III-nitride devices, an area that is of increasing significance as the research focus has moved from not just high performance but also production-worthiness and long-term usage of these devices. Finally, a group of papers on new and relatively less studied ideas for III-nitride electronics, such as interband tunneling, heterojunction bipolar transistors, and high-temperature electronics is included. These areas point to new areas of research and technological innovation going beyond the state of the art into the future. We hope that the breadth and quality of articles in this issue will make it

  5. Roll bonding of strained aluminium

    DEFF Research Database (Denmark)

    Staun, Jakob M.

    2003-01-01

    This report investigates roll bonding of pre-strained (å ~ 4) aluminium sheets to produce high strain material from high purity aluminium (99.996%) and commercial pure aluminium (99.6%). The degree of bonding is investigated by optical microscopy and ultrasonic scanning. Under the right circumsta......This report investigates roll bonding of pre-strained (å ~ 4) aluminium sheets to produce high strain material from high purity aluminium (99.996%) and commercial pure aluminium (99.6%). The degree of bonding is investigated by optical microscopy and ultrasonic scanning. Under the right...... circumstances both materials show good bonding, but the high purity material is excluded because of recrystallisation and the resulting loss of mechanical properties. The effect of cross stacking and roll bonding pre-strained sheets of the commercial purity material is investigated and some dependence...... of the cross rolled volume fraction is found. To further asses this effect, and the anisotropy, it is necessary to acquire knowledge about both texture and microstructure, e.g. by TEM. Roll bonding of pre-strained aluminium is found to be a possible alternative to ARB in the quest for ultra-fine grained...

  6. Aluminium, antiperspirants and breast cancer.

    Science.gov (United States)

    Darbre, P D

    2005-09-01

    Aluminium salts are used as the active antiperspirant agent in underarm cosmetics, but the effects of widespread, long term and increasing use remain unknown, especially in relation to the breast, which is a local area of application. Clinical studies showing a disproportionately high incidence of breast cancer in the upper outer quadrant of the breast together with reports of genomic instability in outer quadrants of the breast provide supporting evidence for a role for locally applied cosmetic chemicals in the development of breast cancer. Aluminium is known to have a genotoxic profile, capable of causing both DNA alterations and epigenetic effects, and this would be consistent with a potential role in breast cancer if such effects occurred in breast cells. Oestrogen is a well established influence in breast cancer and its action, dependent on intracellular receptors which function as ligand-activated zinc finger transcription factors, suggests one possible point of interference from aluminium. Results reported here demonstrate that aluminium in the form of aluminium chloride or aluminium chlorhydrate can interfere with the function of oestrogen receptors of MCF7 human breast cancer cells both in terms of ligand binding and in terms of oestrogen-regulated reporter gene expression. This adds aluminium to the increasing list of metals capable of interfering with oestrogen action and termed metalloestrogens. Further studies are now needed to identify the molecular basis of this action, the longer term effects of aluminium exposure and whether aluminium can cause aberrations to other signalling pathways in breast cells. Given the wide exposure of the human population to antiperspirants, it will be important to establish dermal absorption in the local area of the breast and whether long term low level absorption could play a role in the increasing incidence of breast cancer. PMID:16045991

  7. The toxicity of aluminium in humans.

    Science.gov (United States)

    Exley, C

    2016-06-01

    We are living in the 'aluminium age'. Human exposure to aluminium is inevitable and, perhaps, inestimable. Aluminium's free metal cation, Alaq(3+), is highly biologically reactive and biologically available aluminium is non-essential and essentially toxic. Biologically reactive aluminium is present throughout the human body and while, rarely, it can be acutely toxic, much less is understood about chronic aluminium intoxication. Herein the question is asked as to how to diagnose aluminium toxicity in an individual. While there are as yet, no unequivocal answers to this problem, there are procedures to follow to ascertain the nature of human exposure to aluminium. It is also important to recognise critical factors in exposure regimes and specifically that not all forms of aluminium are toxicologically equivalent and not all routes of exposure are equivalent in their delivery of aluminium to target sites. To ascertain if Alzheimer's disease is a symptom of chronic aluminium intoxication over decades or breast cancer is aggravated by the topical application of an aluminium salt or if autism could result from an immune cascade initiated by an aluminium adjuvant requires that each of these is considered independently and in the light of the most up to date scientific evidence. The aluminium age has taught us that there are no inevitabilities where chronic aluminium toxicity is concerned though there are clear possibilities and these require proving or discounting but not simply ignored. PMID:26922890

  8. Gallium-67 scintigraphy and the Heart

    International Nuclear Information System (INIS)

    Although gallium-67 was initially used for tumor imaging, clinical studies suggested its potential use as a method of detecting occult inflammatory lesions. The demonstration of diffuse myocardial uptake of gallium-67 during Lyme disease myocarditis is consistent with a pattern of diffuse myocarditis as seen in sarcoid myocarditis. Two cases are presented. A critical review of the various applications of gallium-67 scintigraphy to myocardium investigation is carried out

  9. Tuberculosis peritonitis: gallium-67 scintigraphic appearance.

    Science.gov (United States)

    Sumi, Y; Ozaki, Y; Hasegawa, H; Shindoh, N; Katayama, H; Tamamoto, F

    1999-06-01

    Tuberculosis peritonitis is a rare manifestation of extrapulmonary tuberculosis. The results of gallium-67 scintigraphy of three patients with tuberculosis peritonitis were reviewed to assess its usefulness in the diagnosis of this condition. Tuberculosis peritonitis was associated with diffuse or focal abdominal localization and decreased hepatic accumulation of gallium-67. These gallium-67 scan features of tuberculosis peritonitis may help to optimize the diagnosis and management of this disease. PMID:10435380

  10. Friction surfacing of aluminium alloys

    OpenAIRE

    Pereira, Diogo Jorge O. A.

    2012-01-01

    Friction surfacing is a solid state joining process that has attracted much interest in the past decades. This technology allows joining dissimilar metallic materials while avoiding the brittle intermetallic formations, involving temperatures bellow melting point and producing like forged metal structures. Much research using different steels has been made but the same does not happen with aluminium alloys, specially using different aluminium alloys. Friction surface coatings using cons...

  11. Synthesis, characterization and catalytic activity of indium substituted nanocrystalline Mobil Five (MFI) zeolite

    International Nuclear Information System (INIS)

    Highlights: • In situ modification of the MFI zeolite by incorporation of indium. • The samples were characterized by XRD, FTIR, TGA, UV–vis (DRS), SAA, EDX and SEM. • The incorporation of indium was confirmed by XRD, FT-IR, UV–vis (DRS), EDX and TGA. • Hydroxylation of phenol reaction was studied on the synthesized catalysts. - Abstract: A series of indium doped Mobil Five (MFI) zeolite were synthesized hydrothermally with silicon to aluminium and indium molar ratio of 100 and with aluminium to indium molar ratios of 1:1, 2:1 and 3:1. The MFI zeolite phase was identified by XRD and FT-IR analysis. In XRD analysis the prominent peaks were observed at 2θ values of around 6.5° and 23° with a few additional shoulder peaks in case of all the indium incorporated samples suggesting formation of pure phase of the MFI zeolite. All the samples under the present investigation were found to exhibit high crystallinity (∼92%). The crystallite sizes of the samples were found to vary from about 49 to 55 nm. IR results confirmed the formation of MFI zeolite in all cases showing distinct absorbance bands near 1080, 790, 540, 450 and 990 cm−1. TG analysis of In-MFI zeolites showed mass losses in three different steps which are attributed to the loss due to adsorbed water molecules and the two types TPA+ cations. Further, the UV–vis (DRS) studies reflected the position of the indium metal in the zeolite framework. Surface area analysis of the synthesized samples was carried out to characterize the synthesized samples The analysis showed that the specific surface area ranged from ∼357 to ∼361 m2 g−1 and the pore volume of the synthesized samples ranged from 0.177 to 0.182 cm3 g−1. The scanning electron microscopy studies showed the structure of the samples to be rectangular and twinned rectangular shaped. The EDX analysis was carried out for confirmation of Si, Al and In in zeolite frame work. The catalytic activities of the synthesized samples were

  12. Synthesis, characterization and catalytic activity of indium substituted nanocrystalline Mobil Five (MFI) zeolite

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Kishor Kr. [Department of Chemistry, ADP College, Nagaon, Assam 782002 (India); Nandi, Mithun [Department of Chemistry, Gauhati University, Guwahati, Assam 781014 (India); Talukdar, Anup K., E-mail: anup_t@sify.com [Department of Chemistry, Gauhati University, Guwahati, Assam 781014 (India)

    2015-06-15

    Highlights: • In situ modification of the MFI zeolite by incorporation of indium. • The samples were characterized by XRD, FTIR, TGA, UV–vis (DRS), SAA, EDX and SEM. • The incorporation of indium was confirmed by XRD, FT-IR, UV–vis (DRS), EDX and TGA. • Hydroxylation of phenol reaction was studied on the synthesized catalysts. - Abstract: A series of indium doped Mobil Five (MFI) zeolite were synthesized hydrothermally with silicon to aluminium and indium molar ratio of 100 and with aluminium to indium molar ratios of 1:1, 2:1 and 3:1. The MFI zeolite phase was identified by XRD and FT-IR analysis. In XRD analysis the prominent peaks were observed at 2θ values of around 6.5° and 23° with a few additional shoulder peaks in case of all the indium incorporated samples suggesting formation of pure phase of the MFI zeolite. All the samples under the present investigation were found to exhibit high crystallinity (∼92%). The crystallite sizes of the samples were found to vary from about 49 to 55 nm. IR results confirmed the formation of MFI zeolite in all cases showing distinct absorbance bands near 1080, 790, 540, 450 and 990 cm{sup −1}. TG analysis of In-MFI zeolites showed mass losses in three different steps which are attributed to the loss due to adsorbed water molecules and the two types TPA{sup +} cations. Further, the UV–vis (DRS) studies reflected the position of the indium metal in the zeolite framework. Surface area analysis of the synthesized samples was carried out to characterize the synthesized samples The analysis showed that the specific surface area ranged from ∼357 to ∼361 m{sup 2} g{sup −1} and the pore volume of the synthesized samples ranged from 0.177 to 0.182 cm{sup 3} g{sup −1}. The scanning electron microscopy studies showed the structure of the samples to be rectangular and twinned rectangular shaped. The EDX analysis was carried out for confirmation of Si, Al and In in zeolite frame work. The catalytic activities of

  13. Control of gallium incorporation in sol–gel derived CuIn(1−x)GaxS2 thin films for photovoltaic applications

    International Nuclear Information System (INIS)

    Highlights: • CuIn(1−x)GaxS2 thin films were prepared by sol–gel process. • Evolution of lattice parameters is characteristic of a solid solution. • Optical band gap was found to be linearly dependent on the gallium rate. - Abstract: In this paper, we report the elaboration of Cu(In,Ga)S2 chalcopyrite thin films via a sol–gel process. To reach this aim, solutions containing copper, indium and gallium complexes were prepared. These solutions were thereafter spin-coated onto the soda lime glass substrates and calcined, leading to metallic oxides thin films. Expected chalcopyrite films were finally obtained by sulfurization of oxides layers using a sulfur atmosphere at 500 °C. The rate of gallium incorporation was studied both at the solutions synthesis step and at the thin films sulfurization process. Elemental and X-ray diffraction (XRD) analyses have shown the efficiency of monoethanolamine used as a complexing agent for the preparation of CuIn(1−x)GaxS2 thin layers. Moreover, the replacement of diethanolamine by monoethanolamine has permitted the substitution of indium by isovalent gallium from x = 0 to x = 0.4 and prevented the precipitation of copper derivatives. XRD analyses of sulfurized thin films CuIn(1−x)GaxS2, clearly indicated that the increasing rate of gallium induced a shift of XRD peaks, revealing an evolution of the lattice parameter in the chalcopyrite structure. These results were confirmed by Raman analyses. Moreover, the optical band gap was also found to be linearly dependent upon the gallium rate incorporated within the thin films: it varies from 1.47 eV for x = 0 to 1.63 eV for x = 0.4

  14. Strongly-guided indium phosphide/indium gallium arsenic phosphide Mach-Zehnder modulator for optical communications

    Science.gov (United States)

    Betty, Ian Brian

    2006-12-01

    The development of strongly-guided InP/In1-x GaxAsyP 1-y based Mach-Zehnder optical modulators for 10Gb/s telecommunications is detailed. The modulators have insertion losses including coupling as low as 4.5dB, due to the incorporation of monolithically integrated optical mode spot-size converters (SSC's). The modulators are optimized to produce system performance that is independent of optical coupling alignment and for wavelength operation between 1525nm and 1565nm. A negatively chirped Mach-Zehnder modulator design is demonstrated, giving optimal dispersion-limited reach for 10Gb/s ON/OFF-keying modulation. It is shown that the optical system performance for this design can be determined from purely DC based optical measurements. A Mach-Zehnder modulator design invoking nearly no transient frequency shifts under intensity modulation is also presented, for the first time, using phase-shifter implementations based on the Quantum-Confined-Stark-Effect (QCSE). The performance impact on the modulator from the higher-order vertical and lateral waveguide modes found in strongly-guided waveguides has been determined. The impact of these higher-order modes has been minimized using the design of the waveguide bends, MMI structures, and doping profiles. The fabrication process and optical design for the spot-size mode converters are also thoroughly explored. The SSC structures are based on butt-joined vertically tapered passive waveguide cores within laterally flared strongly-guided ridges, making them compatible with any strong-guiding waveguide structure. The flexibility of the SSC process is demonstrated by the superior performance it has also enabled in a 40Gb/s electro-absorption modulator. The presented electro-absorption modulator has 3.6dB fiber-to-fiber insertion loss, polarization dependent loss (PDL) of only 0.3dB over 15dB extinction, and low absolute chirp (|alpha H| < 0.6) over the full dynamic range.

  15. Gallium-67 citrate scan in extrapulmonary tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Lin Wanyu [Taichung Veterans General Hospital (Taiwan). Dept. of Nuclear Medicine; Hsieh Jihfang [Chi-Mei Foundation Hospital, Tainan (Taiwan)

    1999-07-01

    Aim: Whole-body gallium scan was performed to evaluate the usefulness of gallium scan for detecting extrapulmonary tuberculosis (TB) lesions. Methods: Thirty-seven patients with extrapulmonary TB were included in this study. Four patients were found to have two lesions. Totally, 41 lesions were identified, including 19 TB arthritis, 8 spinal TB, 5 TB meningitis, 3 TB lymphadenopathy, 2 TB pericarditis, 1 TB peritonitis, 1 intestinal TB, 1 skin TB and 1 renal TB. Results: Of the 41 extrapulmonary TB lesions, gallium scan detected 32 lesions with a sensitivity of 78%. All the patients with TB meningitis showed negative gallium scan. When the five cases of TB meningitis were excluded, the detection sensitivity of gallium scan increased to 88.9% (32/36). Conclusion: Our data revealed that gallium scan is a convenient and useful method for evaluating extrapulmonary TB lesions other than TB-meningitis. We suggest that gallium scan be included in the clinical routine for patients with suspected extrapulmonary TB. (orig.) [German] Ziel: Es wurden Ganzkoerper-Gallium-Szintigramme angefertigt, um den Nutzen der Gallium-Szintigraphie zur Erfassung von extrapulmonalen Tuberkuloseherden (TB) zu erfassen. Methoden: 37 Patienten mit extrapulmonaler TB wurden eingeschlossen. 4 Patienten hatten 2 Laesionen. Insgesamt wurden 41 Laesionen identifiziert, hierunter 19 TB-Arthritis, 8 spinale TB, 5 TB-Meningitis, 3 TB-Lymphadenopathie, 2 TB-Perikarditis, 1 TB-Peritonitis, 1 intestinale TB, 1 Haut-TB und eine Nieren-TB. Ergebnisse: Von den 41 extrapulmonalen TB-Herden erfasste die Gallium-Szintigraphie 32 Herde mit einer Sensitivitaet von 78%. Alle Patienten mit TB-Meningitis zeigten einen negativen Gallium-Scan. Wenn die 5 Faelle mit TB-Meningitis ausgeschlossen wurden, stieg die Sensitivititaet der Gallium-Szintigraphie auf 88,9% (32/36). Schlussfolgerung: Die Daten zeigen, dass die Gallium-Szintigraphie eine einfache und nuetzliche Methode zur Erfassung extrapulmonaler TB-Herde ist

  16. Dispersion strengthening of aluminium-aluminium-oxide products

    DEFF Research Database (Denmark)

    Hansen, Niels

    1970-01-01

    temperature and at 400°C is in agreement with Orowan's theory. The increase in flow stress at room temperature for strain values below 3 per cent was related to the plastic strain by the equation σ-σoy=k1ε 1/2, where σoy is the initial flow stress and where k1 increases for increasing volume fraction......The true stress-true strain curves at room temperature and at 400°C were determined for various types of aluminium-aluminium-oxide products containing from 0.2 to 4.7 weight per cent of aluminium oxide. The effect of particles on the initial flow stress and the flow stress for 0.2% offset at room...

  17. Preparation of aluminium lakes by electrocoagulation

    OpenAIRE

    Prapai Pradabkham

    2008-01-01

    Aluminium lakes have been prepared by electrocoagulation employing aluminium as electrodes. The electrocoagulation is conducted in an aqueous alcoholic solution and is completed within one hour. The dye content in the lake ranges approximately between 4-32%.

  18. Effect of hydrogen on aluminium and aluminium alloys: A review

    DEFF Research Database (Denmark)

    Ambat, Rajan; Dwarakadasa, E.S.

    1996-01-01

    Susceptibility of aluminium and its alloys towards hydrogen embrittlement has been well established. Still a lot of confusion exists on the question of transport of hydrogen and its possible role in stress corrosion cracking. This paper reviews some of the fundamental properties of hydrogen...... in aluminium and its alloys and its effect on mechanical properties. The importance of hydrogen embrittlement over anodic dissolution to explain the stress corrosion cracking mechanism of these alloys is also examined in considerable detail. The various experimental findings concerning the link between...

  19. Buckwheat stomatal traits under aluminium toxicity

    Directory of Open Access Journals (Sweden)

    Oleksandr E. Smirnov

    2014-04-01

    Full Text Available Aluminium influence on some stomatal parameters of common buckwheat (Fagopyrum esculentum Moench. was studied. Significant changes in stomatal density, stomatal index and stomatal shape coefficient under aluminium treatment were revealed. Stomatal closure and no difference in total stomatal potential conductance index of treatment plants were suggested as aluminium resistance characteristics.

  20. Does Aluminium Trigger Breast Cancer?

    Directory of Open Access Journals (Sweden)

    Peter Jennrich

    2016-08-01

    Full Text Available Summary. Breast cancer is by far the most common cancer in women in the western world. In 90% of breast cancers, environmental factors are among the causes. The frequency with which the tumour occurs in the outer upper part of the breast has risen with above average rates in recent decades. Aluminium salts as ingredients in deodorants and antiperspirants are being absorbed by the body to a greater extent than hitherto assumed. Their toxicity for healthy and diseased breast tissue cells includes various well-documented pathomechanisms. In the sense of primary and secondary prevention, the cancer-triggering potential of aluminium and its use in anti-perspirant deodorants must be re-evaluated. For the same reason the access to a targeted diagnosis and treatment of aluminium loading must be facilitated.

  1. Pulmonary disorders in indium-processing workers

    International Nuclear Information System (INIS)

    The production of indium-tin oxide has increased during the past decade, owing to the increased manufacture of liquid-crystal panels, especially in Japan. We carried out a medical checkup including high resolution CT (HRCT), pulmonary function test, KL-6, SP-D and serum indium concentration, for 40 men (mean age 40.4±12.4 years old) working in an indium plant. Four workers who were all smokers had emphysematous changes on HRCT and one subject (non-smoker) had lung cancer. There were no findings of interstitial changes on HRCT. Serum KL-6 was significantly elevated (over 500 U/ml) in 9 subjects (22.5%). Subjects with a high concentration of serum indium (3 ng/ml). The serum indium concentration positively correlated with the KL-6 level. These results suggest that inhaled indium compounds can cause pulmonary disorders such as interstitial changes. (author)

  2. [Three cases of indium lung].

    Science.gov (United States)

    Taguchi, Osamu; Chonan, Tatsuya

    2006-07-01

    The production of indium tin oxide (ITO) has been increasing during the past decade because of its use in liquid crystal and plasma display panels. Following the first report on lethal lung injury in a ITO worker in 2001, we began pulmonary check-ups for 115 workers in the plant in our capacity of industrial physicians of the plant. Hence, we report interstitial pulmonary disease in 3 workers who had engaged in wet-surface grinding of ITO for 8 to 12 years and had significant lung injuries. The serum indium level and serum concentration of KL-6 were significantly elevated in all 3 cases. One non-smoker case among them showed severe obstructive changes on spirometry and had an episode of repeated bilateral pneumothorax before and during the follow-up period. All 3 cases showed both interstitial and/or emphysematous changes on HRCT. It is suggested that inhaled indium compounds can cause a new and unique interstitial pulmonary disease.

  3. Nanomechanical Characterization of Indium Nano/Microwires

    Directory of Open Access Journals (Sweden)

    N Kiran MSR

    2010-01-01

    Full Text Available Abstract Nanomechanical properties of indium nanowires like structures fabricated on quartz substrate by trench template technique, measured using nanoindentation. The hardness and elastic modulus of wires were measured and compared with the values of indium thin film. Displacement burst observed while indenting the nanowire. ‘Wire-only hardness’ obtained using Korsunsky model from composite hardness. Nanowires have exhibited almost same modulus as indium thin film but considerable changes were observed in hardness value.

  4. High damping indium-tin alloys

    OpenAIRE

    Dooris, A.; Lakes, Roderick S.; Myers, B.; Stephens, N

    2015-01-01

    This research is directed toward the development of materials of high stiffness and high mechanical damping for the purpose of damping vibrations instructures and machinery. To this end, indium-tin alloys are considered. Cast In-Sn exhibits substantial damping for a metal. Quenching substantially improved the damping of indium-tin alloy but the effect gradually disappeared due to aging. Cold work of 1.3% permanent shear strain had the effect of moderately increasing the damping of indium-tin,...

  5. Mechanism of Nickel-Aluminium Alloy Electroplating

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The effect of operating conditions on the aluminium content of Ni-Al alloy deposit and the catalytic function of NaF on electrodeposition in the nonaqueous solution containing aluminium are investigated.The results indicate that the plated aluminuim content will be increased with the rise of current density in a given range.When the current density is 2.5A/dm2,nickle-aluminium alloy containing 13.1 wt% aluminium will be deposited.The plated aluminium content will be increased by 2wt% as 0.1mol/L NaF is added to the bath.

  6. The Soviet American Gallium Experiment (SAGE)

    International Nuclear Information System (INIS)

    A radiochemical experiment using the reaction v/sub e/ = 71Ga + e/sup e/ to determine the integral flux of low-energy neutrinos from the sun is currently under preparation at the Baksan Neutrino Observatory in the USSR. Measurements are scheduled to commence by late 1988 using /approximately/30 tonnes of metallic gallium. With this amount of gallium it should be possible to obtain a fractional statistical accuracy of 12 to 15% after one year (assuming the standard solar model neutrino flux). While initial measurements are in progress, installation of the remaining 30 tonnes of gallium will proceed in order to perform the full 60 tonne experiment

  7. Reduced thermal quenching in indium-rich self-organized InGaN/GaN quantum dots

    KAUST Repository

    ElAfandy, Rami T.

    2012-01-01

    Differences in optical and structural properties of indium rich (27), indium gallium nitride (InGaN) self-organized quantum dots (QDs), with red wavelength emission, and the two dimensional underlying wetting layer (WL) are investigated. Temperature dependent micro-photoluminescence (?PL) reveals a decrease in thermal quenching of the QDs integrated intensity compared to that of the WL. This difference in behaviour is due to the 3-D localization of carriers within the QDs preventing them from thermalization to nearby traps causing an increase in the internal quantum efficiency of the device. Excitation power dependent ?PL shows a slower increase of the QDs PL signal compared to the WL PL which is believed to be due to the QDs saturation. © 2012 American Institute of Physics.

  8. The prophylactic reduction of aluminium intake.

    Science.gov (United States)

    Lione, A

    1983-02-01

    The use of modern analytical methods has demonstrated that aluminium salts can be absorbed from the gut and concentrated in various human tissues, including bone, the parathyroids and brain. The neurotoxicity of aluminium has been extensively characterized in rabbits and cats, and high concentrations of aluminium have been detected in the brain tissue of patients with Alzheimer's disease. Various reports have suggested that high aluminium intakes may be harmful to some patients with bone disease or renal impairment. Fatal aluminium-induced neuropathies have been reported in patients on renal dialysis. Since there are no demonstrable consequences of aluminium deprivation, the prophylactic reduction of aluminium intake by many patients would appear prudent. In this report, the major sources of aluminium in foods and non-prescription drugs are summarized and alternative products are described. The most common foods that contain substantial amounts of aluminium-containing additives include some processed cheeses, baking powders, cake mixes, frozen doughs, pancake mixes, self-raising flours and pickled vegetables. The aluminium-containing non-prescription drugs include some antacids, buffered aspirins, antidiarrhoeal products, douches and haemorrhoidal medications. The advisability of recommending a low aluminium diet for geriatric patients is discussed in detail. PMID:6337934

  9. Electrochemical properties and thermal stability of epoxy coatings electrodeposited on aluminium and modified aluminium surfaces

    Directory of Open Access Journals (Sweden)

    ZORICA M. KACAREVIC-POPOVIC

    2001-12-01

    Full Text Available The corrosion behaviour of epoxy coatings electrodeposited on aluminium, as well as on electrochemically and chemically modified aluminium were investigated during exposure to 3 % NaCl. Electrochemical impedance spectroscopy (EIS and thermogravimetric analysis (TGA were used for the determination of the protective properties of epoxy coatings on aluminium, anodized aluminium, phosphatized and chromatized-phosphatized aluminium. The protective properties of epoxy coatings on anodized and chromatized-phosphatized aluminium are significantly improved with respect to the same epoxy coatings on aluminium and phosphatized aluminium: higher values of the pore resitance and charge-transfer resistance, lower values of the coating capacitance, double-layer capacitance and relative permittivity (from EIS smaller amount of absorbed water inside the coating (From TGA. On the other hand, the lower values of the ipdt temperature indicate a lower thermal stability of the epoxy coatings on anodized and chromatized-phosphatized aluminium.

  10. Recovery mechanisms in nanostructured aluminium

    DEFF Research Database (Denmark)

    Yu, Tianbo; Hansen, Niels; Huang, Xiaoxu

    2012-01-01

    Commercial purity aluminium (99.5%) has been cold rolled to a true strain of 5.5 (99.6% reduction in thickness). The material is very strong but low temperature recovery may be a limiting factor. This has been investigated by isothermal annealing treatments in the temperature range 5–100C. Hardness...

  11. Constitutive modelling of aluminium foams

    NARCIS (Netherlands)

    Wang, W.M.; Lemmen, P.P.M.

    2001-01-01

    In this paper an aluminium foam model is proposed for a vehicle crash analysis. The model assumes that there is no coupling between stresses and strains in different principal directions. The stress in each principle direction is then interpolated from an experimental recorded uniaxial stress strain

  12. Microchemistry in aluminium sheet production

    NARCIS (Netherlands)

    Lok, Z.J.

    2005-01-01

    The production of aluminium sheet alloys from as-cast ingots is a complex process, involving several rolling operations in combination with various thermal heat treatments. Through their influence on the alloy microchemistry and microstructure, these thermomechanical treatments are all aimed at cont

  13. Radiochemical separation of gallium by amalgam exchange

    Science.gov (United States)

    Ruch, R.R.

    1969-01-01

    An amalgam-exchange separation of radioactive gallium from a number of interfering radioisotopes has been developed. A dilute (ca. 0.3%) gallium amalgam is agitated with a slightly acidic solution of 72Ga3+ containing concentrations of sodium thiocyanate and either perchlorate or chloride. The amalgam is then removed and the radioactive gallium stripped by agitation with dilute nitric acid. The combined exchange yield of the perchlorate-thiocyanate system is 90??4% and that of the chloride-thiocyanate system is 75??4%. Decontamination yields of most of the 11 interfering isotopes studied were less than 0.02%. The technique is applicable for use with activation analysis for the determination of trace amounts of gallium. ?? 1969.

  14. Recovery of gallium from phosphorus industry flue

    Institute of Scientific and Technical Information of China (English)

    许可; 邓彤; 戴玉杰; 王静

    2004-01-01

    The flue dust generated during electric furnace production of elemental phosphorus was investigated for the recovery of gallium. Then the flue dust was slurried with water and blended with concentrated sulfuric acid, followed by ageing. The gallium in the dust was thereby converted to soluble sulfate. The factors affecting the dust curing were investigated to understand the process chemistry of the pretreatment. The optimal curing conditions are determined as follows: the mass ratio of dust to water and acid is 1: 1: 1, ageing temperature and time are 200 ℃ and 2 h, respectively. Almost all the gallium available to acid dissolution in the dust, about 900%00 gallium, can be extracted by leaching the cured dust at 80 ℃ for 1 h.

  15. The Baksan gallium solar neutrino experiment

    Energy Technology Data Exchange (ETDEWEB)

    Gavrin, V.N.; Abazov, A.I.; Abdurashitov, D.N.; Anosov, O.L.; Danshin, S.N.; Eroshkina, L.A.; Faizov, E.L.; Gayevsky, V.I.; Girin, S.V.; Kalikhov, A.V.; Knodel, T.V.; Knyshenko, I.I.; Kornoukhov, V.N.; Mezentseva, S.A.; Mirmov, I.N.; Ostrinsky, A.I.; Petukhov, V.V.; Pshukov, A.M.; Revzin, N.Y.; Shikhin, A.A.; Slusareva, Y.D.; Tikhonov, A.A.; Timofeev, P.V.; Veretenkin, E.P.; Vermul, V.M.; Yantz, V.E.; Zakharov, Yu.I.; Zatsepin, G.T.; Zhandarov, V.L. (AN SSSR, Moscow (USSR). Inst. Yadernykh Issledovanij); Bowles, T.J.; Cleveland, B.T.; Elliott, S.R.; O' Brien, S.R.; Wark, D.L.; Wilkerson, J.F. (Los Alamos National Lab., NM (USA)); Davis, R. Jr.; Lande, K. (Pennsylvania Univ., Philadelphia (USA)); Cherry, M.L. (Louisiana State Univ., Baton Rouge (USA)); Kouzes, R.T. (Princeton Univ., NJ (USA)); SAGE Collaboration

    1990-08-01

    A radiochemical {sup 71}Ga-{sup 71}Ge experiment to determine the integral flux of neutrinos from the sun has been constructed at the Baksan Neutrino Observatory in the USSR. Measurements have begun with 30 tonnes of gallium. An additional 30 tonnes of gallium are being installed so as to perform the full experiment with a 60-tonne target. The motivation, experiment procedures, and present status of this experiment are described. (orig.).

  16. Bumblebee pupae contain high levels of aluminium.

    Science.gov (United States)

    Exley, Christopher; Rotheray, Ellen; Goulson, David

    2015-01-01

    The causes of declines in bees and other pollinators remains an on-going debate. While recent attention has focussed upon pesticides, other environmental pollutants have largely been ignored. Aluminium is the most significant environmental contaminant of recent times and we speculated that it could be a factor in pollinator decline. Herein we have measured the content of aluminium in bumblebee pupae taken from naturally foraging colonies in the UK. Individual pupae were acid-digested in a microwave oven and their aluminium content determined using transversely heated graphite furnace atomic absorption spectrometry. Pupae were heavily contaminated with aluminium giving values between 13.4 and 193.4 μg/g dry wt. and a mean (SD) value of 51.0 (33.0) μg/g dry wt. for the 72 pupae tested. Mean aluminium content was shown to be a significant negative predictor of average pupal weight in colonies. While no other statistically significant relationships were found relating aluminium to bee or colony health, the actual content of aluminium in pupae are extremely high and demonstrate significant exposure to aluminium. Bees rely heavily on cognitive function and aluminium is a known neurotoxin with links, for example, to Alzheimer's disease in humans. The significant contamination of bumblebee pupae by aluminium raises the intriguing spectre of cognitive dysfunction playing a role in their population decline.

  17. Friction Welding of Aluminium and Aluminium Alloys with Steel

    Directory of Open Access Journals (Sweden)

    Andrzej Ambroziak

    2014-01-01

    Full Text Available The paper presents our actual knowledge and experience in joining dissimilar materials with the use of friction welding method. The joints of aluminium and aluminium alloys with the different types of steel were studied. The structural effects occurring during the welding process were described. The mechanical properties using, for example, (i microhardness measurements, (ii tensile tests, (iii bending tests, and (iv shearing tests were determined. In order to obtain high-quality joints the influence of different configurations of the process such as (i changing the geometry of bonding surface, (ii using the interlayer, or (iii heat treatment was analyzed. Finally, the issues related to the selection of optimal parameters of friction welding process were also investigated.

  18. Aluminium and nickel in human albumin solutions

    DEFF Research Database (Denmark)

    Gammelgaard, Bente; Sandberg, E

    1989-01-01

    Five different brands of commercially available human albumin solutions for infusion were analysed for their aluminium and nickel contents by atomic absorption spectrometry. The aluminium concentrations ranged from 12 micrograms/l to 1109 micrograms/l and the nickel concentrations ranged from 17...... micrograms/l to 77 micrograms/l. Examination of the aluminium and nickel contents of the constituents for the production of one brand showed too low levels to explain the final contamination of the product. By following the aluminium and nickel concentrations of the same brand during the production...... of a batch of albumin solution, filtration was shown to contribute to contamination, although the largest increase in aluminium as well as nickel concentrations appeared during the bulk concentrating process. To avoid health risks to certain patients, regulations should be established requiring aluminium...

  19. Aluminium in Allergies and Allergen immunotherapy.

    Science.gov (United States)

    Jensen-Jarolim, Erika

    2015-01-01

    Aluminium is a hot topic in the current debate. Exposure occurs due to environmental, dietary and intentional exposure to aluminium, such as in vaccines where it was introduced in 1926. In spite of the fact that it is a typical Th2 adjuvant, aluminium redirects the immune response in systemic allergen immunotherapy (SIT) upon prolonged immunization. SIT in the US, and SLIT in general, are at present non-adjuvanted therapies, but in Europe aluminium is used as adjuvant in most SIT preparations. It enhances the safety of SIT by local deposition of the allergen. Undesired properties of aluminium adjuvants comprise acute and chronic inflammation at the injection site, its Th2 immune stimulatory capacity, its accumulation besides biodistribution in the body. The adjuvant and safety profile of aluminium adjuvants in allergy vaccines are discussed, as well as the need for putting modern delivery systems and adjuvants on the fast track.

  20. Dietary aluminium Intake Level for Rent Animals in a Primary and Secondary Aluminium Industry Surrounding Area

    OpenAIRE

    Mărioara Drugă; Alexandru Trif; Mihai Drugă; Ducu Ştef; Ştefan Munteanu

    2010-01-01

    The study was carried out in an aluminium industry surrounding area on purpose to evaluate dietary aluminium intake level for rent animals originated from fodder and water consumed by them. There were taken feed and water samples in different periods and from increasing distances from industrial platform, determined the aluminium level by atomic spectroscopy and calculated the rations for cattle and poultry. Conclusions: aluminium dietary intake level by ration depends by forage period for st...

  1. A customizable commercial miniaturized 320×256 indium gallium arsenide shortwave infrared camera

    Science.gov (United States)

    Huang, Shih-Che; O'Grady, Matthew; Groppe, Joseph V.; Ettenberg, Martin H.; Brubaker, Robert M.

    2004-10-01

    The design and performance of a commercial short-wave-infrared (SWIR) InGaAs microcamera engine is presented. The 0.9-to-1.7 micron SWIR imaging system consists of a room-temperature-TEC-stabilized, 320x256 (25 μm pitch) InGaAs focal plane array (FPA) and a high-performance, highly customizable image-processing set of electronics. The detectivity, D*, of the system is greater than 1013 cm-√Hz/W at 1.55 μm, and this sensitivity may be adjusted in real-time over 100 dB. It features snapshot-mode integration with a minimum exposure time of 130 μs. The digital video processor provides real time pixel-to-pixel, 2-point dark-current subtraction and non-uniformity compensation along with defective-pixel substitution. Other features include automatic gain control (AGC), gamma correction, 7 preset configurations, adjustable exposure time, external triggering, and windowing. The windowing feature is highly flexible; the region of interest (ROI) may be placed anywhere on the imager and can be varied at will. Windowing allows for high-speed readout enabling such applications as target acquisition and tracking; for example, a 32x32 ROI window may be read out at over 3500 frames per second (fps). Output video is provided as EIA170-compatible analog, or as 12-bit CameraLink-compatible digital. All the above features are accomplished in a small volume < 28 cm3, weight < 70 g, and with low power consumption < 1.3 W at room temperature using this new microcamera engine. Video processing is based on a field-programmable gate array (FPGA) platform with a soft-embedded processor that allows for ease of integration/addition of customer-specific algorithms, processes, or design requirements. The camera was developed with the high-performance, space-restricted, power-conscious application in mind, such as robotic or UAV deployment.

  2. Size-effects in indium gallium arsenide nanowire field-effect transistors

    Science.gov (United States)

    Zota, Cezar B.; Lind, E.

    2016-08-01

    We fabricate and analyze InGaAs nanowire MOSFETs with channel widths down to 18 nm. Low-temperature measurements reveal quantized conductance due to subband splitting, a characteristic of 1D systems. We relate these features to device performance at room-temperature. In particular, the threshold voltage versus nanowire width is explained by direct observation of quantization of the first sub-band, i.e., band gap widening. An analytical effective mass quantum well model is able to describe the observed band structure. The results reveal a compromise between reliability, i.e., VT variability, and on-current, through the mean free path, in the choice of the channel material.

  3. X-Ray Diffraction Analysis on Gallium-Indium Interdiffusion in Quantum Dot Superlattices

    Institute of Scientific and Technical Information of China (English)

    汪辉; 封松林; 徐世杰; 李晴

    2001-01-01

    Thermal-induced interdiffusion in InAs/GaAs quantum dot superlattices is studied by high-resolution x-raydiffraction rocking curve and photoluminescence techniques. With increasing annealing temperatures, up to300meV a blueshift of the emission peak position and down to 16.6meV a narrowing of the line width are foundin the photoluminescence spectra, and respective intensity of the higher-order satellite peaks to lower-order onesin the x-ray rocking curves decreases. Dynamical theory is employed to simulate the measured x-ray diffractiondata. Excellent agreement between the experimental curves and the simulations is achieved when the composition, thickness and stress variations caused by interdiffusion are taken into account. It is found that the significantIn-Ga intermixing occurs even in the as-grown InAs/GaAs quantum dots. The estimated diffusion coefficient is1.8 × 10-17cm2.s-1 at 650 ℃, 3.2 × 10-17cm2·s-1 at 750 ℃, and 1.2 × 10-14 cm2.s-1 at 850℃.

  4. Impact of secondary barriers on copper-indium-gallium-selenide solar-cell operation

    Science.gov (United States)

    Pudov, Alexei O.

    Thin-film solar cells based on CuInSe2 (CIS) absorber with a band gap of Eg = 1.0 eV and also based on CuIn1-x GaxSe2 (CIGS) alloy absorbers with a band-gap range of Eg = 1.0--1.67 eV are investigated in this work. Intermediate "buffer" semiconductor layers in p-n junctions of CIGS solar cells often improve photodiode properties of the devices. The primary goal of the thesis is to study secondary barriers in the conduction band at the buffer/absorber interface, which may limit current transport and thus reduce the efficiency of the solar cells. The secondary goal is to explore alternative wide-bandgap buffers in CIGS cell structures. CIGS cells with standard CdS buffer layers, and alternative ZnS(O,OH) and InS(O,OH) buffer layers were studied. CdS/CuIn1-xGaxSe2 solar cells with variable Ga content have a range of conduction-band offsets (DeltaEc) in the junction from moderately positive (spike offsets) in CdS/CuInSe2 to moderately negative (cliff offsets) in CdS/CuGaSe 2. Moderate conduction-band spikes in CdS/CIS and low-Ga CdS/CIGS are expected to cause distortions in diode current-voltage (J-V) curves of such solar cells under "red" illumination (hnu < Eg(buffer)); no J-V distortions are expected for high-Ga CdS/CIGS with cliff offsets. These predictions were confirmed in experiments: the distortions were absent for cells with Eg above 1.2--1.3 eV, at which CdS/CIGS DeltaE c is near zero. Experiments and numerical simulations showed that one approach to reduce secondary barriers and J-V distortions in low-Ga high-spike cells is to thin the buffer layer(s). Blue photons (hnu above Eg(buffer)) in the solar spectrum induce photoconductivity in the otherwise compensated buffers, which also results in lowering of the secondary barriers. It was shown that CIGS cells with CdS, InS(O,OH), and ZnS(O,OH) buffers have a similar response to "blue" photons: J-V distortion, if present under red light, is reduced or entirely disappears with blue-light exposure within minutes. The distortion re-appearance without blue light is the order of a thousand times slower. Using wider-gap buffers, such as InS(O,OH) and ZnS(O,OH), was shown to produce higher photocurrents in solar cells. This photocurrent improvement is a central direction in the effort of further increasing efficiencies of thin-film solar cells.

  5. Targeting radiopharmaceuticals: comparative biodistribution studies of gallium and indium complexes of multidentate ligands

    Energy Technology Data Exchange (ETDEWEB)

    Mathias, C.J.; Welch, M.J.; Green, M.A.; Thomas, J.A.; Wade, K.R.; Yizhen Sun; Martell, A.E.

    1988-01-01

    New multidentate ligands with structures similar to N,N'-bis(2-hydroxybenzyl)ethylenediamine-N,N'-diacetic acid (HBED) and N,N'-bis(pyridoxyl)ethylenediamine-N,N'-diacetic acid (PLED) were synthesized. The in vitro lipophilicity, electrophoretic behavior, and the in vivo biodistribution were studied for the /sup 111/In- and sup(67,68)Ga-complexes of N,N'-bis(2-hydroxy-3,5-dimethylbenzyl)ethylenediamine-N,N'-diacetic acid (Me/sub 4/HBED); N,N'-bis(5-t-butyl-2-hydroxy-3-methylbenzyl)ethylenediamine-N,N'-diacetic acid (t-butyl HBED); N,N'-bis(2-hydroxy-5-sulfobenzyl)ethylenediamine-N,N'diacetic acid (SHBED); N,N'-bis(2-hydroxy-3,5-dimethylbenzyl)ethylenediamine-N-(2-hydroxyethyl)-N'-acetic acid (HBMA); and N,N'-bis(deoxypyridoxyl)ethylenediamine-N,N'-diacetic acid (DPLED). the biodistribution of the radiometal complexes were carried out in rats and an imaging study was performed in a non-human primate. The rapid clearance of the lipophilic complexes from blood and through the hepatobiliary system was easily demonstrated; as well, the hydrophilic complexes were cleared rapidly through the urinary tract. Positron emission tomographic images were generated from a study in a primate after administration of /sup 68/Ga-t-butyl HBED. These images demonstrate the efficient liver accumulation and rapid hepatobiliary clearance (< 1 h) and differentiate images of the liver and gall bladder.

  6. Evaluation of pled as a chelating ligand for the preparation of gallium and indium radiopharmaceuticals

    Energy Technology Data Exchange (ETDEWEB)

    Green, M.A.; Mathias, C.J.; Welch, M.J.; Taylor, P.; Martell, A.E.

    1985-05-01

    The sexadentate ligand, N,N'-dipyridoxyl-ethylenediamine-N,N'-diacetic acid (PLED), has been shown (Inorg. Chem. 23:1188-1192, 1984) to bind the Ga(III) and In(III) ions with very high affinity (log K = 36.35 and 36.89, respectively). The Ga-68 and In-111 complexes of PLED were prepared and complex formation verified by paper chromatography. Paper electrophoresis using 1 M pH 7.35 HEPES buffer as electrolyte showed single radioactive peaks for In-111 PLED, In-111 EDTA, and In-111 HEDTA, all of which migrated towards the anode. The biodistributions of Ga-68 PLED and In-111 PLED were determined following intravenous injection into rats. The Ga-68 and In-111 complexes behaved identically and were rapidly cleared from the blood via the kidneys into the urine. Paper chromatography suggests that the complexes are excreted intact. At 14 minutes post-injection, 8% of the injected dose was found in the blood, 5% in the kidneys, and 48% in the bladder and urine. At 1 hour, 2% of the dose remained in the blood, 1.5% in the kidneys and 86% in the bladder and urine. Gamma images showed a similar biodistribution and rate of clearance following injection of Ga-68 PLED or In-111 PLED into a stump-tailed macque.

  7. Thermodynamics of reaction of praseodymium with gallium-indium eutectic alloy

    OpenAIRE

    Melchakov, S. Y.; V. A. Ivanov; Yamshchikov, L. F.; Volkovich, V. A.; Osipenko, A. G.; Kormilitsyn, M. V.

    2013-01-01

    Thermodynamic properties of Ga-In eutectic alloys saturated with praseodymium were determined for the first time employing the electromotive force method. The equilibrium potentials of the Pr-In alloys saturated with praseodymium (8.7-12.1 mol.% Pr) and Pr-Ga-In alloys (containing 0.0012-6.71 mol.% Pr) were measured between 573-1073 K. Pr-In alloy containing solid PrIn3 with known thermodynamic properties was used as the reference electrode when measuring the potentials of ternary Pr-In-Ga al...

  8. Thermochemistry and phase diagram studies in the copper(indium,gallium)selenium system

    Science.gov (United States)

    Ider, Muhsin

    Polycrystalline Cu(In,Ga)Se2 and related semiconductors show great potential as alternative materials in production of high efficiency solar cells. This dissertation reports the experimental determination of Gibbs energy changes and phase diagram calculations for selected sections of the Cu-Ga-In-Se system. The Gibbs energy changes were measured with solid-state electrochemical cells and this data along with selected literature data were assessed and model parameters suggested. The homogeneity range of beta-Cu2-xSe was measured by coulometric titration and the thermodynamic properties for defect species estimated. The composition difference between the Se-rich and the Cu-rich boundaries was measured at 900K. A defect model was developed based on vacancy formation on the Cu sublattice. The gas phase equilibrium data for Cu-Se system and the results of a recent assessment of selenium unary system were used to predict defect concentrations. A thermodynamic description of the Cu2Se-In2Se 3 was obtained by optimization of the available phase equilibrium and thermodynamic information along with the direct results of EMF experiments. The Gibbs energy of formation of alpha-CuInSe2 was directly measured by a solid oxide galvanic cell experiment. The transformation enthalpy and Gibbs energy data for CuIn3Se5 and CuIn5Se 8 were estimated. The Redlich-Kister model with a 3-coefficient expression was employed to define the Gibbs energy of the liquid phase. The intermediate beta-CuIn 3Se5 and gamma-CuIn5Se8 phases were modeled with a 2-coefficient expansion of the Redlich-Kister model. The alpha and delta modifications of CuInSe2 phases were modeled with a specific sublattice model. A reasonable agreement between the model calculated values and the thermodynamic phase equilibrium data was achieved. The thermochemistry and phase diagram of GaSe system was critically studied. The activity of Ga was measured along the liquidus between 800--1000K. Selected invariant phase transition temperatures were measured and transition enthalpies were calculated from the EMF measurements. A self-consistent thermodynamic data was obtained. The associated and sublattice models were used to represent the Gibbs energy of the liquid and alpha-Ga2Se3 phases, respectively. The Gibbs energy of formation of CuGaSe2 was measured by an EMT experiment. The phase diagram of Cu-Ga system was calculated and the liquid phase Ga activity measurements was measured for 2 Ga rich compositions.

  9. Electrical Instability of Amorphous-Indium-Gallium-Zinc-Oxide Thin-Film Transistors under Ultraviolet Illumination

    Science.gov (United States)

    Lan-Feng, Tang; Hai, Lu; Fang-Fang, Ren; Dong, Zhou; Rong, Zhang; You-Dou, Zheng; Xiao-Ming, Huang

    2016-03-01

    Not Available Supported by the Key Industrial R&D Program of Jiangsu Province under Grand No BE2015155, the Priority Academic Program Development of Jiangsu Higher Education Institutions, and the Fundamental Research Funds for the Central Universities under Grant No 021014380033.

  10. Dual-band technology on indium gallium arsenide focal plane arrays

    Science.gov (United States)

    Dixon, Peter; Hess, Cory D.; Li, Chuan; Ettenberg, Martin; Trezza, John

    2011-06-01

    While InGaAs-based SWIR imaging technology has been improved dramatically over the past 10 years, the motivation remains to reduce Size Weight and Power (SWaP) for applications in Intelligence Surveillance and Reconnaissance (ISR). Goodrich ISR Systems, Princeton (Sensors Unlimited, Inc.) has continued to improve detector sensitivity. Additionally, SUI is working jointly with DRS-RSTA to develop innovative techniques for manufacturing dual-band focal planes to provide next generation technology for not only reducing SWaP for SWIR imagers, but also to combine imaging solutions for providing a single imager for Visible Near-SWIR (VNS) + LW imaging solutions. Such developments are targeted at reducing system SWaP, cost and complexity for imaging payloads on board UASs as well as soldier deployed systems like weapon sights. Our motivation is to demonstrate capability in providing superior image quality in fused LWIR and SWIR imaging systems, while reducing the total system SWaP and cost by enabling Short Wave and Thermal imaging in a single uncooled imager. Under DARPA MTO awarded programs, a LW bolometer (DRS-RSTA) is fabricated on a Short Wave (SW) InGaAs Vis-SWIR (SUI-Goodrich) Imager. The combined imager is a dual-band Sensor-Chip Assembly which is capable of imaging in VIS-SWIR + LW. Both DRS and Goodrich have developed materials and process enhancements to support these dual-band platform investigations. The two imagers are confocal and coaxial with respect to the incident image plane. Initial work has completed a single Read Out Integrated Circuit (ROIC) capable of running both imagers. The team has hybridized InGaAs Focal planes to 6" full ROIC wafers to support bolometer fabrication onto the SW array.

  11. Ellipsometry study of process deposition of amorphous Indium Gallium Zinc Oxide sputtered thin films

    Energy Technology Data Exchange (ETDEWEB)

    Talagrand, C., E-mail: talagrand@emse.fr [Ecole des Mines de Saint-Etienne CMP-GC, Dept PS2, Gardanne, 880 route de Mimet (France); Boddaert, X. [Ecole des Mines de Saint-Etienne CMP-GC, Dept PS2, Gardanne, 880 route de Mimet (France); Selmeczi, D.G.; Defranoux, C. [Semilab Semiconductor Physics Laboratory Co. Ltd., Budapest, 1117 (Hungary); Collot, P. [Ecole Nationale Supérieure d' Arts et Métiers ParisTech, Aix-en-Provence, 2 cours des Arts et Métiers (France)

    2015-09-01

    This paper reports on an InGaZnO optical study by spectrometric ellipsometry. First of all, the fitting results of different models and different structures are analysed to choose the most appropriate model. The Tauc–Lorentz model is suitable for thickness measurements but a more complex model allows the refractive index and extinction coefficient to be extracted more accurately. Secondly, different InGaZnO process depositions are carried out in order to investigate stability, influence of deposition time and uniformity. Films present satisfactory optical stability over time. InGaZnO optical property evolution as a function of deposition time is related to an increase in temperature. To understand the behaviour of uniformity, mapping measurements are correlated to thin film resistivity. Results show that temperature and resputtering are the two phenomena that affect IGZO uniformity. - Highlights: • Model and structure are investigated to fit IGZO ellipsometric angles. • Maximum refractive index rises with substrate temperature and thus deposition time. • Resputtering leads to inhomogeneity in IGZO electrical and optical properties.

  12. Amorphous indium gallium zinc oxide thin film grown by pulse laser deposition technique

    Science.gov (United States)

    Mistry, Bhaumik V.; Joshi, U. S.

    2016-05-01

    Highly electrically conducting and transparent in visible light IGZO thin film were grown on glass substrate at substrate temperature of 400 C by a pulse laser deposition techniques. Structural, surface, electrical, and optical properties of IGZO thin films were investigated at room temperature. Smooth surface morphology and amorphous nature of the film has been confirmed from the AFM and GIXRD analysis. A resistivity down to 7.7×10-3 V cm was reproducibly obtained while maintaining optical transmission exceeding 70% at wavelengths from 340 to 780 nm. The carrier densities of the film was obtain to the value 1.9×1018 cm3, while the Hall mobility of the IGZO thin film was 16 cm2 V-1S-1.

  13. Does Aluminium Trigger Breast Cancer?

    OpenAIRE

    Peter Jennrich; Claus Schulte-Uebbing

    2016-01-01

    Summary. Breast cancer is by far the most common cancer in women in the western world. In 90% of breast cancers, environmental factors are among the causes. The frequency with which the tumour occurs in the outer upper part of the breast has risen with above average rates in recent decades. Aluminium salts as ingredients in deodorants and antiperspirants are being absorbed by the body to a greater extent than hitherto assumed. Their toxicity for healthy and diseased breast tissue cells includ...

  14. A biogeochemical cycle for aluminium?

    Science.gov (United States)

    Exley, Christopher

    2003-09-15

    The elaboration of biogeochemical cycles for elements which are known to be essential for life has enabled a broad appreciation of the homeostatic mechanisms which underlie element essentiality. In particular they can be used effectively to identify any part played by human activities in element cycling and to predict how such activities might impact upon the lithospheric and biospheric availability of an element in the future. The same criteria were the driving force behind the construction of a biogeochemical cycle for aluminium, a non-essential element which is a known ecotoxicant and a suspected health risk in humans. The purpose of this exercise was to examine the concept of a biogeochemical cycle for aluminium and not to review the biogeochemistry of this element. The cycle as presented is rudimentary and qualitative though, even in this nascent form, it is informative and predictive and, for these reasons alone, it is deserving of future quantification. A fully fledged biogeochemical cycle for aluminium should explain the biospheric abundance of this element and whether we should expect its (continued) active involvement in biochemical evolution.

  15. A bakable aluminium vacuum chamber with an aluminium flange and metal seal for ultrahigh vacuum

    International Nuclear Information System (INIS)

    A bakable (2000C) aluminium alloy vacuum chamber (6063-T6) with an aluminium alloy (2219-T87) flange and metal seal (Helicoflex-HN: aluminium O-ring) has been constructed. Such components may be used in the construction of the vacuum chamber in proton synchrotrons and electron storage rings. (author)

  16. Toxicity of aluminium on five aquatic invertebrates; Aluminiums toksisitet paa 5 akvatiske invertebrater

    Energy Technology Data Exchange (ETDEWEB)

    Moe, J. [Oslo Univ. (Norway)

    1996-01-01

    The conference paper deals with the experiments done by investigating the effects from the toxicity of aluminium on aquatic invertebrates. The aim of the experiments was to compare the toxicity of unstable aluminium compounds with stable forms of aluminium. 8 refs., 2 figs., 2 tabs.

  17. Window structure for passivating solar cells based on gallium arsenide

    Science.gov (United States)

    Barnett, Allen M. (Inventor)

    1985-01-01

    Passivated gallium arsenide solar photovoltaic cells with high resistance to moisture and oxygen are provided by means of a gallium arsenide phosphide window graded through its thickness from arsenic rich to phosphorus rich.

  18. Gallium-67 uptake in cutaneous lesions of mycosis fungoides

    Energy Technology Data Exchange (ETDEWEB)

    Nishimi, L.; Chen, D.C.; Ansari, A.N.; Siegel, M.E.

    1988-02-01

    The literature on gallium imaging in mycosis fungoides is limited and conflicting. A case of mycosis fungoides with increased uptake of Ga-67 in clinically noninfected skin lesions is reported. The literature regarding mycosis fungoides and gallium imaging is reviewed.

  19. Aluminium in foodstuffs and diets in Sweden.

    Science.gov (United States)

    Jorhem, L; Haegglund, G

    1992-01-01

    The levels of aluminium have been determined in a number of individual foodstuffs on the Swedish market and in 24 h duplicate diets collected by women living in the Stockholm area. The results show that the levels in most foods are very low and that the level in vegetables can vary by a factor 10. Beverages from aluminium cans were found to have aluminium levels not markedly different from those in glass bottles. Based on the results of the analysis of individual foods, the average Swedish daily diet was calculated to contain about 0.6 mg aluminium, whereas the mean content of the collected duplicate diets was 13 mg. A cake made from a mix containing aluminium phosphate in the baking soda was identified as the most important contributor of aluminium to the duplicate diets. Tea and aluminium utensils were estimated to increase the aluminium content of the diets by approximately 4 and 2 mg/day, respectively. The results also indicate that a considerable amount of aluminium must be introduced from other sources. PMID:1542992

  20. Control of gallium incorporation in sol–gel derived CuIn{sub (1−x)}Ga{sub x}S{sub 2} thin films for photovoltaic applications

    Energy Technology Data Exchange (ETDEWEB)

    Bourlier, Yoan [Institut de Recherche sur les Composants logiciels et matériels pour l’Information et la Communication Avancée (IRCICA), CNRS USR 3380, Université Lille 1, 50 avenue Halley, 59655 Villeneuve d’Ascq CEDEX (France); Cristini Robbe, Odile [Institut de Recherche sur les Composants logiciels et matériels pour l’Information et la Communication Avancée (IRCICA), CNRS USR 3380, Université Lille 1, 50 avenue Halley, 59655 Villeneuve d’Ascq CEDEX (France); Laboratoire de Physique des Lasers, Atomes et Molécules (PhLAM), CNRS UMR 8523, Université Lille, 59655 Villeneuve d’Ascq CEDEX (France); Lethien, Christophe [Institut de Recherche sur les Composants logiciels et matériels pour l’Information et la Communication Avancée (IRCICA), CNRS USR 3380, Université Lille 1, 50 avenue Halley, 59655 Villeneuve d’Ascq CEDEX (France); Laboratoire de Physique des Lasers, Atomes et Molécules (PhLAM), CNRS UMR 8523, Université Lille, 59655 Villeneuve d’Ascq CEDEX (France); Institut d’Electronique, de Microélectronique et de Nanotechnologie (IEMN), CNRS UMR 8520, Avenue Poincaré, 59652 Villeneuve d’Ascq CEDEX (France); and others

    2015-10-15

    Highlights: • CuIn{sub (1−x)}Ga{sub x}S{sub 2} thin films were prepared by sol–gel process. • Evolution of lattice parameters is characteristic of a solid solution. • Optical band gap was found to be linearly dependent on the gallium rate. - Abstract: In this paper, we report the elaboration of Cu(In,Ga)S{sub 2} chalcopyrite thin films via a sol–gel process. To reach this aim, solutions containing copper, indium and gallium complexes were prepared. These solutions were thereafter spin-coated onto the soda lime glass substrates and calcined, leading to metallic oxides thin films. Expected chalcopyrite films were finally obtained by sulfurization of oxides layers using a sulfur atmosphere at 500 °C. The rate of gallium incorporation was studied both at the solutions synthesis step and at the thin films sulfurization process. Elemental and X-ray diffraction (XRD) analyses have shown the efficiency of monoethanolamine used as a complexing agent for the preparation of CuIn{sub (1−x)}Ga{sub x}S{sub 2} thin layers. Moreover, the replacement of diethanolamine by monoethanolamine has permitted the substitution of indium by isovalent gallium from x = 0 to x = 0.4 and prevented the precipitation of copper derivatives. XRD analyses of sulfurized thin films CuIn{sub (1−x)}Ga{sub x}S{sub 2,} clearly indicated that the increasing rate of gallium induced a shift of XRD peaks, revealing an evolution of the lattice parameter in the chalcopyrite structure. These results were confirmed by Raman analyses. Moreover, the optical band gap was also found to be linearly dependent upon the gallium rate incorporated within the thin films: it varies from 1.47 eV for x = 0 to 1.63 eV for x = 0.4.

  1. Fabrication methods and applications of microstructured gallium based liquid metal alloys

    Science.gov (United States)

    Khondoker, M. A. H.; Sameoto, D.

    2016-09-01

    This review contains a comparative study of reported fabrication techniques of gallium based liquid metal alloys embedded in elastomers such as polydimethylsiloxane or other rubbers as well as the primary challenges associated with their use. The eutectic gallium–indium binary alloy (EGaIn) and gallium–indium–tin ternary alloy (galinstan) are the most common non-toxic liquid metals in use today. Due to their deformability, non-toxicity and superior electrical conductivity, these alloys have become very popular among researchers for flexible and reconfigurable electronics applications. All the available manufacturing techniques have been grouped into four major classes. Among them, casting by needle injection is the most widely used technique as it is capable of producing features as small as 150 nm width by high-pressure infiltration. One particular fabrication challenge with gallium based liquid metals is that an oxide skin is rapidly formed on the entire exposed surface. This oxide skin increases wettability on many surfaces, which is excellent for keeping patterned metal in position, but is a drawback in applications like reconfigurable circuits, where the position of liquid metal needs to be altered and controlled accurately. The major challenges involved in many applications of liquid metal alloys have also been discussed thoroughly in this article.

  2. Aluminium exclusion and aluminium tolerance in woody plants

    OpenAIRE

    Ivano eBrunner; Christoph eSperisen

    2013-01-01

    The aluminium (Al) cation Al3+ is highly rhizotoxic and is a major stress factor to plants on acid soils, which cover large areas of tropical and boreal regions. Many woody plant species are native to acid soils and are well adapted to high Al3+ conditions. In tropical regions, both woody Al accumulator and non-Al accumulator plants occur, whereas in boreal regions woody plants are non-Al accumulators. The mechanisms of these adaptations can be divided into those that facilitate the exclusion...

  3. Superconductor-semiconductor-superconductor planar junctions of aluminium on DELTA-doped gallium arsenide

    DEFF Research Database (Denmark)

    Taboryski, Rafael Jozef; Clausen, Thomas; Kutchinsky, jonatan;

    1997-01-01

    We have fabricated and characterized planar superconductor-semiconductor-superconductor (S-Sm-S) junctions with a high quality (i.e. low barrier) interface between an n++ modulation doped conduction layer in MBE grown GaAs and in situ deposited Al electrodes. The Schottky barrier at the S...

  4. Studies on deep electronic levels in silicon and aluminium gallium arsenide alloys

    International Nuclear Information System (INIS)

    This thesis reports on investigations of the electrical and optical properties of deep impurity centers, related to the transition metals (TMs) Ti, Mo, W, V and Ni, in silicon. Emission rates, capture cross sections and photoionization cross sections for these impurities were determined by means of various Junction Space Charge Techniques (JSCTs), such as Deep Level Transient Spectroscopy (DLTS), dark capacitance transient and photo capacitance transient techniques. Changes in Gibbs free energy as a function of temperature were calculated for all levels. From this temperature dependence, the changes in enthalpy and entropy involved in the electron and hole transitions were deduced. The influence of high electric fields on the electronic levels in chalcogen-doped silicon were investigated using the dark capacitance transient technique. The enhancement of the electron emission from the deep centers indicated a more complex field enhancement model than the expected Poole-Frenkel effect for coulombic potentials. The possibility to determine charge states of defects using the Poole-Frenkel effect, as often suggested, is therefore questioned. The observation of a persistent decrease of the dark conductivity due to illumination in simplified AlGaAs/GaAs high Electron Mobility Transistors (HEMTs) over the temperature range 170K< T<300K is reported. A model for this peculiar behavior, based on the recombination of electrons in the two-dimensional electron gas (2DEG) located at the AlGaAs/GaAs interface with holes generated by a two-step excitation process via the deep EL2 center in the GaAs epilayer, is put forward

  5. Gallium-67 scintigraphy in acute pancreatitis

    Energy Technology Data Exchange (ETDEWEB)

    Al-Suhaili, A.R.; Bahar, R.; Nawaz, K.; Higazy, E.; Wafai, I.; Nema, T.A.; Eriksson, S.; Abdel-Dayem, H.M.

    1988-04-01

    Acute pancreatitis is a serious surgical problem with a high incidence of mortality. Both ultrasound and X-ray CT have problems in identifying the extent and severity of the disease and the response to therapy. /sup 67/Ga-citrate has been used in 21 patients with clinically diagnosed acute pancreatitis: 9 patients had X-ray CT and 15 had US examination. Gallium scans were more sensitive than X-ray CT and US in detecting the extent and severity of acute pancreatitis. In addition, gallium was helpful to monitor the response to therapy when the scan was repeated at various intervals in three patients. A subtraction technique using /sup 99m/Tc-tin colloid and /sup 67/Ga-citrate was helpful to mask the liver uptake of gallium and clearly identify the extent of acute pancreatitis.

  6. Preparation of aluminium lakes by electrocoagulation

    Directory of Open Access Journals (Sweden)

    Prapai Pradabkham

    2008-07-01

    Full Text Available Aluminium lakes have been prepared by electrocoagulation employing aluminium as electrodes. The electrocoagulation is conducted in an aqueous alcoholic solution and is completed within one hour. The dye content in the lake ranges approximately between 4-32%.

  7. Lactobacillus plantarum CCFM639 alleviates aluminium toxicity.

    Science.gov (United States)

    Yu, Leilei; Zhai, Qixiao; Liu, Xiaoming; Wang, Gang; Zhang, Qiuxiang; Zhao, Jianxin; Narbad, Arjan; Zhang, Hao; Tian, Fengwei; Chen, Wei

    2016-02-01

    Aluminium (Al) is the most abundant metal in the earth's crust. Al exposure can cause a variety of adverse physiological effects in humans and animals. Our aim was to demonstrate that specific probiotic bacteria can play a special physiologically functional role in protection against Al toxicity in mice. Thirty strains of lactic acid bacteria (LAB) were tested for their aluminium-binding ability, aluminium tolerance, their antioxidative capacity, and their ability to survive the exposure to artificial gastrointestinal (GI) juices. Lactobacillus plantarum CCFM639 was selected for animal experiments because of its excellent performance in vitro. Forty mice were divided into four groups: control, Al only, Al plus CCFM639, and Al plus deferiprone (DFP). CCFM639 was administered at 10(9) CFU once daily for 10 days, followed by a single oral dose of aluminium chloride hexahydrate at 5.14 mg aluminium (LD50) for each mouse. The results showed that CCFM639 treatment led to a significant reduction in the mortality rates with corresponding decrease in intestinal aluminium absorption and in accumulation of aluminium in the tissues and amelioration of hepatic histopathological damage. This probiotic treatment also resulted in alleviation of hepatic, renal, and cerebral oxidative stress. The treatment of L. plantarum CCFM639 has potential as a therapeutic dietary strategy against acute aluminium toxicity.

  8. Acoustic properties of aluminium foams

    Directory of Open Access Journals (Sweden)

    García, L. E.

    2008-09-01

    Full Text Available The article discusses normal incidence sound absorption by aluminium foam manufactured with powder metallurgy technology. Aluminium foams with different surface morphologies were obtained by varying the type of precursor and adding filler materials during the foaming process. The sound absorption coefficients found for these aluminium foams were compared to the coefficient for commercial foams marketed under the name ALPORAS. The effect of foam thickness on the absorption coefficient was studied for each sample prepared. The combination of good acoustic and mechanical properties makes aluminium foams particularly attractive products. The study included an analysis of the effect of 2-, 5- and 10-cm air gaps on the sound absorption coefficient. The results showed that such gaps, which are routinely used in construction to reduce the reverberation period in indoor premises, raised the low frequency absorption coefficient significantly. This increase was found to depend on aluminium foam density and thickness and the depth of the air gap. In this same line, we have investigated the absorption coefficient of the aluminium foams combined with a mineral fiber panel.Se presenta un estudio del coeficiente de absorción acústica a incidencia normal de espumas de aluminio fabricadas mediante la técnica pulvimetalúrgica. Se fabricaron espumas de aluminio de distinta morfología superficial variando el tipo de precursor y usando materiales de relleno durante el proceso de espumación. Se muestra un estudio comparativo del coeficiente de absorción acústica de las espumas de aluminio fabricadas y las espumas comerciales conocidas como ALPORAS. Para cada muestra fabricada se estudió la influencia del espesor sobre el valor del coeficiente de absorción.El atractivo de las espumas de aluminio radica en que en ellas se combinan interesantes propiedades acústicas y mecánicas. Se analizó el efecto de una cámara de aire de 2, 5 y 10 cm de anchura sobre el

  9. Gallium-67 scintigraphy in patients with hemochromatosis treated by deferoxamine

    Energy Technology Data Exchange (ETDEWEB)

    Nagamachi, Shigeki; Hoshi, Hiroaki; Jinnouchi, Seishi; Ono, Seiji; Watanabe, Katsushi

    1988-05-01

    Gallium scintigraphy was performed as an aid for determining the presence or absence of malignant neoplasm in two patients with hemochromatosis treated by deferoxamine. However, gallium scan images could not be obtained. So gallium scintigraphy was performed once more to investigate the cause of low activity. Both patients had heavy urinary excretion of gallium in the first 24 hrs after the injection, and activity was very low on the day of examination. This phenomenon may be attributed to the effect of deferoxamine which is highly bound to the gallium.

  10. Gallium-67 scintigraphy: a cornerstone in functional imaging of lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Even-Sapir, Einat [Department of Nuclear Medicine, Sourasky Medical Center and Sackler School of Medicine, Tel-Aviv University, Tel Aviv (Israel); Israel, Ora [Department of Nuclear Medicine, Rambam Medical Center and Faculty of Medicine, Technion-Israel Institute of Technology, 35254, Haifa (Israel)

    2003-06-01

    Until recently, gallium-67 scintigraphy (GS) has been the best available functional imaging modality for evaluating patients with non-Hodgkin's lymphoma (NHL) and Hodgkin's disease (HD). The diagnostic accuracy of GS in detecting lymphoma is based on optimisation of the imaging protocol, knowledge of potential physiological and benign sites of {sup 67}Ga uptake, and the Ga avidity characteristics of the individual lymphoma. As {sup 67}Ga is a tumour viability agent, the role of GS is primarily at follow-up. A residual mass persisting on CT after treatment poses a common clinical dilemma: it may indicate the presence of viable lymphoma, which requires further treatment, or it can be benign, consisting of only fibrotic and necrotic tissues. GS can successfully differentiate between these conditions. Routine follow-up with GS may allow early diagnosis of recurrence and early institution of treatment. Reversion of a positive GS to a negative test, and the rapidity with which this occurs has a high predictive value for the outcome of the individual patient. Lymphoma showing a normal GS early during treatment has a better prognosis than lymphoma with persistence of pathological findings. Other tumour-seeking single-photon emitting agents, such as thallium-201, technetium-99m methoxyisobutylisonitrile and indium-111 octreotide, have been investigated in lymphoma, primarily as an alternative to GS in specific clinical settings, but are of limited value. The role of radioimmunoscintigraphy is gaining importance in conjunction with radioimmunotherapy. Fluorine-18 fluorodeoxyglucose (FDG) imaging of lymphoma using either dedicated or camera-based PET systems is gradually replacing GS for assessment of lymphoma. FDG overcomes some of the limitations of GS while sharing its tumour viability characteristics. The extensive clinical knowledge and experience accumulated over three decades with GS in lymphoma provides a solid background as well as a model for the

  11. Indium Single-Ion Frequency Standard

    Science.gov (United States)

    Nagourney, Warren

    2001-01-01

    A single laser-cooled indium ion is a promising candidate for an ultimate resolution optical time or frequency standard. It can be shown that single ions from group IIIA of the periodic table (indium, thallium, etc.) can have extremely small systematic errors. In addition to being free from Doppler, transit-time and collisional shifts, these ions are also quite insensitive to perturbations from ambient magnetic and electric fields (mainly due to the use of a J=0-0 transition for spectroscopy). Of all group IIIA ions, indium seems to be the most practical, since it is heavy enough to have a tolerable intercombination cooling transition rate and (unlike thallium) has transitions which are easily accessible with frequency multiplied continuous-wave lasers. A single indium ion standard has a potential inaccuracy of one part in 10(exp 18) for integration times of 10(exp 6) seconds. We have made substantial progress during the grant period in constructing a frequency standard based upon a single indium ion. At the beginning of the grant period, single indium ions were being successfully trapped, but the lasers and optical systems were inadequate to achieve the desired goal. We have considerably improved the stability of the dye laser used to cool the ions and locked it to a molecular resonance line, making it possible to observe stable cooling-line fluorescence from a single indium ion for reasonable periods of time, as required by the demands of precision spectroscopy. We have substantially improved the single-ion fluorescence signal with significant benefits for the detection efficiency of forbidden transitions using the 'shelving' technique. Finally, we have constructed a compact, efficient UV 'clock' laser and observed 'clock' transitions in single indium ions using this laser system. We will elaborate on these accomplishments.

  12. Quantification of indium in steel using PIXE

    Energy Technology Data Exchange (ETDEWEB)

    Oliver, A.; Miranda, J.; Rickards, J.; Cheang, J.C.

    1989-04-01

    The quantitative analysis of steel endodontics tools was carried out using low-energy protons (/le/ 700 keV). A computer program for a thick-target analysis which includes enhancement due to secondary fluorescence was used. In this experiment the L-lines of indium are enhanced due to the proximity of other elements' K-lines to the indium absorption edge. The results show that the ionization cross section expression employed to evaluate this magnitude is important. (orig.).

  13. Quantification of indium in steel using PIXE

    International Nuclear Information System (INIS)

    The quantitative analysis of steel endodontics tools was carried out using low-energy protons (≤ 700 keV). A computer program for a thick-target analysis which includes enhancement due to secondary fluorescence was used. In this experiment the L-lines of indium are enhanced due to the proximity of other elements' K-lines to the indium absorption edge. The results show that the ionization cross section expression employed to evaluate this magnitude is important. (orig.)

  14. Aging of coprecipitated gallium and gadolinium hydroxides

    International Nuclear Information System (INIS)

    The X-ray graphical and X-ray spectroscopic methods have been used to investigate aging under parent solution at 25, 50, 90 deg and thermolysis in the 250-1000 deg range of mixed gallium and gadolinium hydroxides coprecipitated at pH 8.6 by ammonium hydroxide from the nitrate solution (Gd:Ga=3:5). Hydroxopolycompounds With garnet prestructure are stated to be precipitated under the mentioned conditions. Their dehydration and crystallization of gallium-gadolinium garnet take place during aging under parent solution and thermolysis

  15. Difficult diagnosis and localization of focal nesidioblastosis: clinical implications of 68Gallium-DOTA-D-Phe1-Tyr3-octreotide PET scanning

    Science.gov (United States)

    Kim, Jae Ri; Shin, Yong Chan; Cho, Young Min; Kim, Hongbeom; Kwon, Wooil; Han, Young Min; Kim, Sun-Whe

    2016-01-01

    Focal nesidioblastosis is a rare cause of endogenous hyperinsulinemic hypoglycemia in adults. Because it is difficult to localize and detect with current imaging modalities, nesidioblastosis is challenging for biliary-pancreatic surgeons. 68Gallium-DOTA-D-Phe1-Tyr3-octreotide PET scanning and 111indium-pentetreotide diethylene triamine pentaacetic acid octreotide scanning may be superior to conventional imaging modalities in determining the localization of nesidioblastosis. We report the successful surgical treatment of a 54-year-old woman with focal hyperplasia of the islets of Langerhans, who experienced frequent hypoglycemic symptoms and underwent various diagnostic examinations with different results. PMID:27433465

  16. Difficult diagnosis and localization of focal nesidioblastosis: clinical implications of (68)Gallium-DOTA-D-Phe(1)-Tyr(3)-octreotide PET scanning.

    Science.gov (United States)

    Kim, Jae Ri; Jang, Jin-Young; Shin, Yong Chan; Cho, Young Min; Kim, Hongbeom; Kwon, Wooil; Han, Young Min; Kim, Sun-Whe

    2016-07-01

    Focal nesidioblastosis is a rare cause of endogenous hyperinsulinemic hypoglycemia in adults. Because it is difficult to localize and detect with current imaging modalities, nesidioblastosis is challenging for biliary-pancreatic surgeons. (68)Gallium-DOTA-D-Phe(1)-Tyr(3)-octreotide PET scanning and (111)indium-pentetreotide diethylene triamine pentaacetic acid octreotide scanning may be superior to conventional imaging modalities in determining the localization of nesidioblastosis. We report the successful surgical treatment of a 54-year-old woman with focal hyperplasia of the islets of Langerhans, who experienced frequent hypoglycemic symptoms and underwent various diagnostic examinations with different results. PMID:27433465

  17. Photoluminescence of indium-rich copper indium sulfide quantum dots

    International Nuclear Information System (INIS)

    The enhanced photoluminescence (PL) for In-rich copper indium sulfide quantum dots (CIS QDs) was observed. The conduction electron-Cu vacancy recombination and the donor–acceptor pair (DAP) defect recombination were considered to exist in CIS QDs at the same time. The temperature-dependent PL study showed that the emission of these QDs might be mainly originated from the recombination between electrons in the quantized conduction band and holes in the copper vacancy acceptor when x was 0.500 (CuxIn1−xS). However, the temperature coefficient of PL peak position decreased when x was 0.237. That meant the DAP recombination increased in the In-rich CIS QDs. - Highlights: • The enhanced photoluminescence (PL) for In-rich CuInS2 QDs with [Cu]/[In] molar ratios of 0.31. • The conduction electron-Cu vacancy recombination and DAP were considered to exist and the temperature-independent DAP recombination was enhanced in the In-rich CuInS2 QDs

  18. A Reaction Coating on Aluminium Alloys by Laser Processing

    NARCIS (Netherlands)

    Zhou, X.B.; Hosson, J.Th.M. De

    1993-01-01

    An aluminium oxide layer of 100 µm in thickness has been successfully coated on aluminium alloy 6061 and pure aluminium using a powder mixture of silicon oxide and aluminium by laser processing. A strong Al/Al2O3 interface was formed. The exothermic chemical reaction between SiO2 and Al may promote

  19. Shot peening of aluminium alloys

    International Nuclear Information System (INIS)

    Shot peening is a process of cold-hammering where a metallic surface is pelted with spherical grains. Each grain bumping into the surface acts as a hammer head and creates a small crater. The overlapping of these craters produces a residual compression layer just underneath the surface. It is well known that cracks cannot spread in a compression zone. In most cases of fatigue rupture and stress corrosion cracks propagate from the surface towards the inside so shot peening allows a longer lifetime of castings. Moreover most materials present a better resistance due to the cold-hammering effect of shot peening. Metallic surfaces can be treated in workshops or directly on site. Typical pieces that undergo shot peening on site are storing tanks, gas and steam turbines, tubes of steam generators and piping in oil or nuclear or chemical industries. This article describes shot peening from a theoretical and general point of view and presents the application to aluminium-lithium alloys. In the case of aluminium alloys shot peening can be used to shape the piece (peen-forming). (A.C.)

  20. Long-chain amine-templated synthesis of gallium sulfide and gallium selenide nanotubes

    Science.gov (United States)

    Seral-Ascaso, A.; Metel, S.; Pokle, A.; Backes, C.; Zhang, C. J.; Nerl, H. C.; Rode, K.; Berner, N. C.; Downing, C.; McEvoy, N.; Muñoz, E.; Harvey, A.; Gholamvand, Z.; Duesberg, G. S.; Coleman, J. N.; Nicolosi, V.

    2016-06-01

    We describe the soft chemistry synthesis of amine-templated gallium chalcogenide nanotubes through the reaction of gallium(iii) acetylacetonate and the chalcogen (sulfur, selenium) using a mixture of long-chain amines (hexadecylamine and dodecylamine) as a solvent. Beyond their role as solvent, the amines also act as a template, directing the growth of discrete units with a one-dimensional multilayer tubular nanostructure. These new materials, which broaden the family of amine-stabilized gallium chalcogenides, can be tentatively classified as direct large band gap semiconductors. Their preliminary performance as active material for electrodes in lithium ion batteries has also been tested, demonstrating great potential in energy storage field even without optimization.We describe the soft chemistry synthesis of amine-templated gallium chalcogenide nanotubes through the reaction of gallium(iii) acetylacetonate and the chalcogen (sulfur, selenium) using a mixture of long-chain amines (hexadecylamine and dodecylamine) as a solvent. Beyond their role as solvent, the amines also act as a template, directing the growth of discrete units with a one-dimensional multilayer tubular nanostructure. These new materials, which broaden the family of amine-stabilized gallium chalcogenides, can be tentatively classified as direct large band gap semiconductors. Their preliminary performance as active material for electrodes in lithium ion batteries has also been tested, demonstrating great potential in energy storage field even without optimization. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr01663d

  1. Synchrotron X-ray fluorescence microscopy of gallium in bladder tissue following gallium maltolate administration during urinary tract infection.

    Science.gov (United States)

    Ball, Katherine R; Sampieri, Francesca; Chirino, Manuel; Hamilton, Don L; Blyth, Robert I R; Sham, Tsun-Kong; Dowling, Patricia M; Thompson, Julie

    2013-11-01

    A mouse model of cystitis caused by uropathogenic Escherichia coli was used to study the distribution of gallium in bladder tissue following oral administration of gallium maltolate during urinary tract infection. The median concentration of gallium in homogenized bladder tissue from infected mice was 1.93 μg/g after daily administration of gallium maltolate for 5 days. Synchrotron X-ray fluorescence imaging and X-ray absorption spectroscopy of bladder sections confirmed that gallium arrived at the transitional epithelium, a potential site of uropathogenic E. coli infection. Gallium and iron were similarly but not identically distributed in the tissues, suggesting that at least some distribution mechanisms are not common between the two elements. The results of this study indicate that gallium maltolate may be a suitable candidate for further development as a novel antimicrobial therapy for urinary tract infections caused by uropathogenic E. coli.

  2. Synchrotron X-Ray Fluorescence Microscopy of Gallium in Bladder Tissue following Gallium Maltolate Administration during Urinary Tract Infection

    Science.gov (United States)

    Sampieri, Francesca; Chirino, Manuel; Hamilton, Don L.; Blyth, Robert I. R.; Sham, Tsun-Kong; Dowling, Patricia M.; Thompson, Julie

    2013-01-01

    A mouse model of cystitis caused by uropathogenic Escherichia coli was used to study the distribution of gallium in bladder tissue following oral administration of gallium maltolate during urinary tract infection. The median concentration of gallium in homogenized bladder tissue from infected mice was 1.93 μg/g after daily administration of gallium maltolate for 5 days. Synchrotron X-ray fluorescence imaging and X-ray absorption spectroscopy of bladder sections confirmed that gallium arrived at the transitional epithelium, a potential site of uropathogenic E. coli infection. Gallium and iron were similarly but not identically distributed in the tissues, suggesting that at least some distribution mechanisms are not common between the two elements. The results of this study indicate that gallium maltolate may be a suitable candidate for further development as a novel antimicrobial therapy for urinary tract infections caused by uropathogenic E. coli. PMID:23877680

  3. Gallium-positive Lyme disease myocarditis

    International Nuclear Information System (INIS)

    In the course of a work-up for fever of unknown origin associated with intermittent arrhythmias, a gallium scan was performed which revealed diffuse myocardial uptake. The diagnosis of Lyme disease myocarditis subsequently was confirmed by serologic titers. One month following recovery from the acute illness, the abnormal myocardial uptake completely resolved

  4. Direct Band Gap Wurtzite Gallium Phosphide Nanowires

    NARCIS (Netherlands)

    Assali, S.; Zardo, I.; Plissard, S.; Kriegner, D.; Verheijen, M.A.; Bauer, G.; Meijerink, A.; Belabbes, A.; Bechstedt, F.; Haverkort, J.E.M.; Bakkers, E.P.A.M.

    2013-01-01

    The main challenge for light-emitting diodes is to increase the efficiency in the green part of the spectrum. Gallium phosphide (GaP) with the normal cubic crystal structure has an indirect band gap, which severely limits the green emission efficiency. Band structure calculations have predicted a di

  5. Epoxy coatings electrodeposited on aluminium and modified aluminium surfaces

    Directory of Open Access Journals (Sweden)

    Lazarević Zorica Ž.

    2002-01-01

    Full Text Available The corrosion behaviour and thermal stability of epoxy coatings electrodeposited on modified aluminum surfaces (anodized, phosphatized and chromatized-phosphatized aluminium were monitored during exposure to 3% NaCl solution, using electrochemical impedance spectroscopy (EIS and thermogravimetric analysis (TGA. Better protective properties of the epoxy coatings on anodized and chromatized-phosphatized aluminum with respect to the same epoxy coatings on aluminum and phosphatized aluminum were obtained: higher values of Rp and Rct and smaller values of Cc and Cd, from EIS, and a smaller amount of absorbed water inside the coating, from TGA. On the other hand, a somewhat lower thermal stability of these coatings was obtained (smaller values of the ipdt temperature. This behavior can be explained by the less porous structure of epoxy coatings on anodized and chromatized-phosphatized aluminum, caused by a lower rate of H2 evolution and better wet ability.

  6. Spin Injection in Indium Arsenide

    Directory of Open Access Journals (Sweden)

    Mark eJohnson

    2015-08-01

    Full Text Available In a two dimensional electron system (2DES, coherent spin precession of a ballistic spin polarized current, controlled by the Rashba spin orbit interaction, is a remarkable phenomenon that’s been observed only recently. Datta and Das predicted this precession would manifest as an oscillation in the source-drain conductance of the channel in a spin-injected field effect transistor (Spin FET. The indium arsenide single quantum well materials system has proven to be ideal for experimental confirmation. The 2DES carriers have high mobility, low sheet resistance, and high spin orbit interaction. Techniques for electrical injection and detection of spin polarized carriers were developed over the last two decades. Adapting the proposed Spin FET to the Johnson-Silsbee nonlocal geometry was a key to the first experimental demonstration of gate voltage controlled coherent spin precession. More recently, a new technique measured the oscillation as a function of channel length. This article gives an overview of the experimental phenomenology of the spin injection technique. We then review details of the application of the technique to InAs single quantum well (SQW devices. The effective magnetic field associated with Rashba spin-orbit coupling is described, and a heuristic model of coherent spin precession is presented. The two successful empirical demonstrations of the Datta Das conductance oscillation are then described and discussed.

  7. Ammonothermal Growth of Gallium Nitride

    Science.gov (United States)

    Pimputkar, Siddha

    Bulk, single crystal Gallium Nitride (GaN) crystals are essential for enabling high performance electronic and optoelectronic devices by providing arbitrarily oriented, high quality, large, single crystal GaN substrates. Methods of producing single crystals of sufficient size and quality at a rate that would enable successful commercialization has been a major focus for research groups and companies worldwide. Recent advances have demonstrated remarkable improvements, though high cost and lack of high volume production remain key challenges. Major investments in bulk GaN growth were made at UCSB with particular focus on the ammonothermal method. The existing lab was upgraded and a new facility was designed and built with improved experimental setups for ammonothermal growth of GaN. The facilities can simultaneously operate up to 15 reactors of differing designs and capabilities with the ability to grow crystals up to 2 inches in diameter. A novel in-situ technique was devised to investigate the growth chemistry which occurs at typical operating conditions of 3,000 atm and 600 °C. Improvements in ammonothermal GaN include improved growth rates for c-plane by a factor of four to 344 μm/day with an overall record growth rate of 544 μm/day achieved for the (112¯2) plane. Crystal qualities comparable to that of the seed crystal were achieved. Impurity concentrations for transition metals were consistently reduced by a factor of 100 to concentrations below 1017 atoms/cm3. Optical transparency was improved by significantly reducing the yellow coloration typically seen for ammonothermal GaN. Single crystal GaN was successfully grown on large seeds and a 1 inch x ½ inch x ½ inch GaN crystal was demonstrated. To better understand the growth chemistry, models were created for the decomposition of ammonia under growth conditions, with initial experiments performed using the designed in-situ setup to verify the model's accuracy. To investigate the surface morphology and

  8. Gallium 67 scintigraphy in glomerular disease

    Energy Technology Data Exchange (ETDEWEB)

    Bakir, A.A.; Lopez-Majano, V.; Levy, P.S.; Rhee, H.L.; Dunea, G.

    1988-12-01

    To evaluate the diagnostic usefulness of gallium 67 scintigraphy in glomerular disease, 45 patients with various glomerulopathies, excluding lupus nephritis and renal vasculitis, were studied. Persistent renal visualization 48 hours after the gallium injection, a positive scintigram, was graded as + (less than), ++ (equal to), and +++ (greater than) the hepatic uptake. Positive scintigrams were seen in ten of 16 cases of focal segmental glomerulosclerosis, six of 11 cases of proliferative glomerulonephritis, and one case of minimal change, and one of two cases of membranous nephropathy; also in three of six cases of sickle glomerulopathy, two cases of diabetic neuropathy, one of two cases of amyloidosis, and one case of mild chronic allograft rejection. The 25 patients with positive scans were younger than the 20 with negative scans (31 +/- 12 v 42 +/- 17 years; P less than 0.01), and exhibited greater proteinuria (8.19 +/- 7.96 v 2.9 +/- 2.3 S/d; P less than 0.01) and lower serum creatinine values (2 +/- 2 v 4.1 +/- 2.8 mg/dL; P less than 0.01). The amount of proteinuria correlated directly with the intensity grade of the gallium image (P less than 0.02), but there was no correlation between the biopsy diagnosis and the outcome of the gallium scan. It was concluded that gallium scintigraphy is not useful in the differential diagnosis of the glomerular diseases under discussion. Younger patients with good renal function and heavy proteinuria are likely to have a positive renal scintigram regardless of the underlying glomerulopathy.

  9. Refractory oxides containing aluminium and barium

    OpenAIRE

    Davies T.J.; Biedermann M.; Q-G. Chen; Emblem H. G.; Al-Douri W. A.

    1998-01-01

    Oxides containing aluminium and barium, optionally with chromium, are refractory with several possible industrial uses. A gel precursor of an oxide having the formula BaO.n(Al2xCr2yO3), where 1aluminium salt or a solution of an aluminium salt and a chromium III salt, then forming a gel which was fired to obtain the desired oxide. Filaments may be drawn as the gel is forming or extr...

  10. Dietary aluminium Intake Level for Rent Animals in a Primary and Secondary Aluminium Industry Surrounding Area

    Directory of Open Access Journals (Sweden)

    Mărioara Drugă

    2010-05-01

    Full Text Available The study was carried out in an aluminium industry surrounding area on purpose to evaluate dietary aluminium intake level for rent animals originated from fodder and water consumed by them. There were taken feed and water samples in different periods and from increasing distances from industrial platform, determined the aluminium level by atomic spectroscopy and calculated the rations for cattle and poultry. Conclusions: aluminium dietary intake level by ration depends by forage period for studied species, rations structure and distance from industrial platform and didn’t reach toxic level in any case.

  11. Aluminium Process Fault Detection and Diagnosis

    Directory of Open Access Journals (Sweden)

    Nazatul Aini Abd Majid

    2015-01-01

    Full Text Available The challenges in developing a fault detection and diagnosis system for industrial applications are not inconsiderable, particularly complex materials processing operations such as aluminium smelting. However, the organizing into groups of the various fault detection and diagnostic systems of the aluminium smelting process can assist in the identification of the key elements of an effective monitoring system. This paper reviews aluminium process fault detection and diagnosis systems and proposes a taxonomy that includes four key elements: knowledge, techniques, usage frequency, and results presentation. Each element is explained together with examples of existing systems. A fault detection and diagnosis system developed based on the proposed taxonomy is demonstrated using aluminium smelting data. A potential new strategy for improving fault diagnosis is discussed based on the ability of the new technology, augmented reality, to augment operators’ view of an industrial plant, so that it permits a situation-oriented action in real working environments.

  12. Deformation features of aluminium in tensile tests

    International Nuclear Information System (INIS)

    It is presented a method to analyse stress-strain curves. Plastic and elastic strains were studied. The strains were done by tensile tests in four types of materials: highly pure aluminium, pure aluminium, commercially pure aluminium and aluminium - uranium. The chemical compositions were obtained by spectroscopy analysis and neutron activation analysis. Tensile tests were carried out at three strain rates, at room temperature, 100,200, 300 and 4000C, with knives extensometer and strain-gages to studied the elastic strain region. A multiple spring model based on two springs model to analyse elastic strain caused by tests without extensometers, taking in account moduli of elasticity and, an interactive analysis system with graphic capability were developed. It was suggested a qualitative model to explain the quantized multielasticity of Bell. (M.C.K.)

  13. Steam Initiated Surface Modification of Aluminium Alloys

    DEFF Research Database (Denmark)

    Din, Rameez Ud

    , crystalline nano-particles, role of steam-based treatment on adhesion of industrially applied powder coating, and investigations of a failed painted aluminium window profile due to defects in the extruded profile. Chapters 13 and 14 describe the overall discussion, conclusions and future work based......The extensive demand of aluminium alloys in various industries such as in transportationis mainly due to the high strength to weight ratio, which could be translated into fuel economy and efficiency. Corrosion protection of aluminium alloys is an important aspect for all applications which includes...... the use of aluminium alloys in the painted form requiring a conversion coating to improve the adhesion. Chromate based conversion coating processes are extremely good for these purposes, however the carcinogenic and toxic nature of hexavalent chromium led to the search for more benign and eco...

  14. Steam generated conversion coating on aluminium alloys

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Jellesen, Morten Stendahl; Ambat, Rajan

    and growth of oxide film on different intermetallic particles and corrosion behaviour of such alloys.Surface morphology was observed by using FEG-SEM, EDX and FIB-SEM. Metal oxide surface characterization and compositional depth profiling were investigated by using XPS and GD-OES respectively......Aluminium and its alloys are widely used in aerospace industry owing to their high strength to weight ratio. The surface of aluminium under normal conditions has a thin oxide film (2.5-10 nm) responsible for its inherent corrosion resistance. This oxide film can further be converted or transformed......) depending on the preparation parameters/conditions. Moreover, with the knowledge of factors controlling film growth, composition and morphology, such oxide layers carry huge potential for practical applications. Pure aluminium (AA1090, 99.94 wt. %) and other aluminium alloy surfaces were exposed to high...

  15. Shear Viscosity of Aluminium under Shock Compression

    Institute of Scientific and Technical Information of China (English)

    LIU Fu-Sheng; YANG Mei-Xia; LIU Qi-Wen; CHEN Jun-Xiang; JING Fu-Qian

    2005-01-01

    @@ Based on the Newtonian viscous fluid model and the analytic perturbation theory of Miller and Ahrens for the oscillatory damping of a sinusoidal shock front, a flyer-impact technique is developed to investigate the effecti veviscosity of shocked aluminium.

  16. Determination of indium in fluedust and zinc ore

    Energy Technology Data Exchange (ETDEWEB)

    Rajesh, N.; Subramanian, M.S. (Indian Inst. of Tech., Madras (India). Dept. of Chemistry)

    1991-01-01

    A radiochemical displacement method has been developed for the determination of trace amounts of indium using radioactive zinc dithizonate as the reagent. The ease with which indium can be quantitatively collected over ferric hydroxide is put to advantage in developing the above method. The collection method in conjunction with the radiodisplacement method is used to determine indium in fluedust and zinc ore. The method is sensitive down to 2 {mu}g indium in 10 ml of aqueous volume. (orig.).

  17. Selective recovery of indium from lead-smelting dust

    OpenAIRE

    Sawai, Hikaru; Rahman, Ismail M. M.; Tsukagoshi, Yoshinori; Wakabayashi, Tomoya; Maki, Teruya; Mizutanai, Satoshi; Hasegawa, Hiroshi

    2015-01-01

    Non-ferrous smelting dust, especially lead-smelting dust (LSD), contains percent levels of indium and thus constitutes a novel indium resource. The main difficulty in recovering indium from LSD is the coexisting presence of lead and zinc. In this study, a unique indium separation process was designed, combining techniques that involve washing with a chelant, leaching with acid and precipitation as hydroxide. The majority of the Pb in the LSD was selectively separated during chelant-assisted w...

  18. Preparation for Ultra High Pure Indium Metal for Optoelectronic Applications

    OpenAIRE

    Shashwat V. Joshi; Amit Kachhadiya; Prof. Minal S. Dani; Prof.Indravadan B Dave

    2014-01-01

    Ultra high pure Indium metal is extensively used in optoelectronic devices. Indium and its alloys become potential candidates in aerospace, defense and communication sectors. Purification of Indium has been done by Instrolec-200 Refiner followed by Directional Melting/ Freezing and Solidification Systems. Major targeted impurities are Metallic impurities Ag, Al, As, Bi, Ca, Cu, Fe, Ga, Ge, Mg, Pb, Sb, Si, Sn, and Zn. Purified Indium is characterized by analytical tec...

  19. Indium-111 leukocyte scanning and fracture healing

    International Nuclear Information System (INIS)

    This study was undertaken to determine the specificity of indium-111 leukocyte scans for osteomyelitis when fractures are present. Midshaft tibial osteotomies were performed in 14 New Zealand white rabbits, seven of which were infected postoperatively with Staphylococcus aureus per Norden's protocol. All 14 rabbits were scanned following injection with 75 microCi of indium 111 at 72 h after osteotomy and at weekly intervals for 4 weeks. Before the rabbits were killed, the fracture sites were cultured to document the presence or absence of infection. The results of all infected osteotomy sites were positive, whereas no positive scans were found in the noninfected osteotomies. We concluded from this study that uncomplicated fracture healing does not result in a positive indium-111 leukocyte scan

  20. Preparation and characterization of mesoporous indium oxide

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yi-zhe; CHENG Zhi-xuan; PAN Qing-yi; DONG Xiao-wen; ZHANG Jian-cheng; PAN Ling-li

    2009-01-01

    Indium oxide nanocrystals with mesoporous structure were successfully synthesized by using triblock copolymer as a template,and characterized by thermogravimetry-differential scanning calorimeter (TG-DSC),X-ray powder diffraction (XRD),high resolution transmission electron microscopy (HRTEM) and N2 adsorption.A high EO/PO ratio is thought to be the key point to prepare mesoporous In2O3.The results show that the average pore diameter of the products is 6 nm,the BET surface area is 54.78 m2/g,and the adsorbing pore volume is 0.345 cm3/g.After comparing with normal indium oxide nanoparticles by BET test,mesoporous indium oxide demonstrates a large difference in adsorbing pore volume and average pore diameters from normal ones.

  1. Bone marrow aluminium storage in renal failure.

    OpenAIRE

    Kaye, M.

    1983-01-01

    Using the staining method for aluminium with the ammonium salt of aurine tricarboxylic acid, aluminon, 18 patients with end stage renal disease gave positive reactions in iliac crest bone biopsies and 11 of these had positive staining in the bone marrow. In one the marrow was positive and the bone negative. The marrow reaction is putatively regarded as caused by aluminium storage in unidentified cells, possibly of the macrophage system which are strongly fluorescent when examined after prior ...

  2. DETERMINATION OF IMPURITY ELEMENTS IN ALUMINIUM

    Institute of Scientific and Technical Information of China (English)

    侯小琳; 张永保

    1994-01-01

    Twenty five impurity elements in aluminium applied as reactor material are determined.Titanium and nickel are determined with epithermal neutron activation analysis(NAA),magnesium and silicon by inductance coupling plasma emission spectra(ICP),other elements by thermal NAA.The fission coefficient of uranium is given by an experiment,the interferences of uranium to Ce,Nd,Mo,Zr,La,Sm are subtracted.The detection limits of these methods to all of impurity elements in aluminium are calculated.

  3. Silane based coating of aluminium mold

    DEFF Research Database (Denmark)

    2013-01-01

    having at least one closed cavity is provided, at least one surface of the at least one cavity being an aluminium surface coated with a silane based coating layer. The silane based anti-stiction coating improves the anti-stiction properties of the mold which may allow for molding and demolding...... of structures which would otherwise be difficult to mold. The resistance of the coated aluminium mold is significantly improved by applying a silane-based coating layer....

  4. Electrical Conductivity of Aluminium Alloy Foams

    Institute of Scientific and Technical Information of China (English)

    凤仪; 郑海务; 朱震刚; 祖方遒

    2002-01-01

    Closed-cell aluminium alloy foams were produced using the powder metallurgical technique. The effect of porosityand cell diameter on the electrical conductivity of foams was investigated and the results were compared with anumber of models. It was found that the percolation theory can be successfully applied to describe the dependenceof the electrical conductivity of aluminium alloy foams on the relative density. The cell diameter has a negligibleeffect on the electrical conductivity of foams.

  5. TRANSPARENT CONDUCTING OXIDE SYNTHESIS OF ALUMINIUM DOPED ZINC OXIDES BY CHEMICAL COPRECIPITATION

    Directory of Open Access Journals (Sweden)

    Silvia Maioco

    2013-03-01

    Full Text Available Aluminium doped zinc oxides (AZO are promising replacements for tin doped indium oxides (ITO but thin films show a wide range of physical properties strongly dependent on deposition process conditions. Submicrometric 1% aluminum doped zinc oxide ceramics (AZO are examined, prepared by coprecipitation, from Zn(NO32 and Al(NO33 aqueous solutions, sintered at 1200°C and subsequently annealed in 10-16 atm controlled oxygen fugacity atmospheres, at 1000°C. Electrical resistivity diminishes by two orders of magnitude after two hours of annealing and the Seebeck coefficient gradually changes from -140 to -50 µV/K within 8 h. It is concluded that increased mobility is dominant over the increased carrier density, induced by changes in metal-oxygen stoichiometry

  6. Ongoing characterization of passivated aluminium nanopowders

    Energy Technology Data Exchange (ETDEWEB)

    Kwok, Q.S.M.; Fouchard, R.C.; Turcotte, A-M.; Abdel-Qader, Z.; Jones, D.E.G. [Natural Resources Canada, CANMET, Canadian Explosives Research Laboratory, Ottawa, ON (Canada)

    2002-04-01

    For characterization, the thermal behaviour of two aluminium nanopowders - Alss and Alssef - in air was determined using differential scanning calorimetry (DSC), simultaneous thermogravimetry-DTA (TG-DTA) and accelerating rate calorimetry (ARC). Alss and Alssef were found to be less reactive to air than previously determined for Als And Alex, possibly due to their thicker and different type of passivating layer. Stability determination for Alss and Alssef in a wet oxidizing environment was carried out using ARC, whereas outgassing behaviour of mixtures of ammonium dinitramide (ADN) and the various aluminium powders was investigated using TG-DTA-FTIR-MS (Fourier Transform Infrared Spectrometry-Mass Spectrometry). The addition of various aluminium powders resulted in only minimal effect on the thermal stability of ADN. Electrostatic discharge, friction sensitivities of ADN and its mixtures with various aluminium powders, and thermal stability and sensitivity of mixtures of nano-sized molybdenum trioxide with aluminium nanopowders were also studied. The electrostatic discharge sensitivity of molybdenum trioxide was shown to increase by the addition of aluminium nanopowders. 23 refs., 5 tabs., 7 figs.

  7. Survey of the market, supply and availability of gallium

    Energy Technology Data Exchange (ETDEWEB)

    Rosi, F.D.

    1980-07-01

    The objective of this study was to assess the present consumption and supply of gallium, its potential availability in the satellite power system (SPS) implementation time frame, and commercial and new processing methods for increasing the production of gallium. Findings are reported in detail. The findings strongly suggest that with proper long range planning adequate gallium would be available from free-enterprise world supplies of bauxite for SPS implementation.

  8. Psoas abscess localization by gallium scan in aplastic anemia

    International Nuclear Information System (INIS)

    Gallium 67 scanning is an effective method of detecting inflammatory lesions, especially abscesses. A 10-year-old boy with aplastic anemia and severe leukopenia and granulocytopenia had a psoas abscess diagnosed by gallium scan. The patient died with Candida sepsis 18 days after bone marrow transplantation. At autopsy, a chronic psoas abscess with Candida was found. The gallium scan offers a clinically effective and noninvasive means of evaluating suspected infection in the granulocytopenia patient. (U.S.)

  9. Indium 111 leucocyte scintigraphy in abdominal sepsis

    International Nuclear Information System (INIS)

    We have studied the clinical utility of indium 111 autologous leucocyte scintigraphy retrospectively in 45 patients presenting with suspected intra-abdominal sepsis. The sensitivity was 95% (21/22) and the specificity was 91% (21/23). Some 34 of the studies (17 positive and 17 negative) were considered helpful in furthering patient management (76%) and 8, unhelpful (18%). In 3, the study results were misleading and led to inappropriate treatment. Indium 111 scintigraphy, whether positive or negative, provides information in patients with suspected intra-abdominal sepsis upon which therapeutic decisions can be based. (orig.)

  10. The usefulness of gallium scintigraphy in idiopathic interstitial pneumonia

    International Nuclear Information System (INIS)

    We evaluated the value of gallium scintigraphy in 23 patients with idiopathic interstitial pneumonia. The degree of gallium lung uptake was compared with chest radiographic, pathologic as well as clinical findings. Particular attention was paid to pathologic findings which were categorized by the degrees of interstitial infiltrate composed of inflammatory cells, activity of alveolar endothelium, cellularity of fibroblasts and collagen fibers. The degree of gallium lung uptake was not necessarily correlated with the severity of the radiographic findings, but reflected the pathological findings well. We conclude that gallium scintigraphy is useful in the evaluation of the activity of idiopathic interstitial pneumonia. (author)

  11. Heat treatment of aluminium strip coils; Gluehbehandlung von Aluminium-Bandbunden

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Dominik; Dambauer, Georg [LOI Thermprocess GmbH, Essen (Germany)

    2012-08-15

    Nowadays, aluminium strip coils are increasingly heat-treated in single-coil lifting hearth furnaces SCL. Flexible, individual heat treatment allows fast reactions to short term requirements for the production of aluminium strip and offers energy saving possibilities. The following report describes the advantages of single-coil hearth furnaces in terms of flexibility, energy consumption and possible configurations. (orig.)

  12. A preliminary study of the dermal absorption of aluminium from antiperspirants using aluminium-26.

    Science.gov (United States)

    Flarend, R; Bin, T; Elmore, D; Hem, S L

    2001-02-01

    Aluminium chlorohydrate (ACH), the active ingredient in many antiperspirants, was labeled with the radioisotope 26Al. The labeled ACH was then fractionated into about 100 samples using gel filtration chromatography. Each fraction was analyzed for 26Al and total aluminium content. Aluminium-26 was only detected in the fractions that also contained aluminium, which verified that the ACH was uniformly labeled. 84 mg of the labeled ACH was then applied to a single underarm of two adult subjects with blood and urine samples being collected over 7 weeks. Tape-stripping and mild washings of the skin were also collected for the first 6 days. Results indicate that only 0.012% of the applied aluminium was absorbed through the skin. At this rate, about 4 microg of aluminium is absorbed from a single use of ACH on both underarms. This is about 2.5% of the aluminium typically absorbed by the gut from food over the same time period. Therefore, a one-time use of ACH applied to the skin is not a significant contribution to the body burden of aluminium.

  13. Design of welded aluminium connections (Entwurf und Berechnung von Aluminium Schweissverbindungen)

    NARCIS (Netherlands)

    Soetens, F.

    1998-01-01

    In the past two decades considerable research effort has been put into welded aluminium connections in order to better understand their structural behaviour and to up-date the design rules in the existing standards at the time [1]. Since weids in aluminium are more critical compared to steel, the ab

  14. Aluminium exclusion and aluminium tolerance in woody plants

    Directory of Open Access Journals (Sweden)

    Ivano eBrunner

    2013-06-01

    Full Text Available The aluminium (Al cation Al3+ is highly rhizotoxic and is a major stress factor to plants on acid soils, which cover large areas of tropical and boreal regions. Many woody plant species are native to acid soils and are well adapted to high Al3+ conditions. In tropical regions, both woody Al accumulator and non-Al accumulator plants occur, whereas in boreal regions woody plants are non-Al accumulators. The mechanisms of these adaptations can be divided into those that facilitate the exclusion of Al3+ from root cells (exclusion mechanisms and those that enable plants to tolerate Al3+ once it has entered the root and shoot symplast (internal tolerance mechanisms. The biochemical and molecular basis of these mechanisms have been intensively studied in several crop plants and the model plant Arabidopsis. In this review, we examine the current understanding of Al3+ exclusion and tolerance mechanisms from woody plants. In addition, we discuss the ecology of woody non-Al accumulator and Al accumulator plants, and present examples of Al3+ adaptations in woody plant populations. This paper complements previous reviews focusing on crop plants and provides insights into evolutionary processes operating in plant communities that are widespread on acid soils.

  15. Regulations in interaction of indium monochloride with concentrated water solutions of indium trichloride at various temperature

    International Nuclear Information System (INIS)

    The equilibrium concentration of univalent indium is determined at temperatures 20-50 deg C. At concentration of the trichloride of 1.8-4.8 mol/l the equilibrium concentration of univalent indium is defined by the balance of disproportionation-reproportionation, and at higher concentration of the trichloride by solubility of the corresponding solid phase. The temperature dependences for solubility of these compounds are obtained

  16. Aluminium as heating fuel. Tests with aluminium powder prove suitability in principle. Aluminium als Heizungs-Brennstoff. Versuche mit Aluminiumpulver beweisen prinzipielle Eignung

    Energy Technology Data Exchange (ETDEWEB)

    Weber, R.

    1990-12-01

    Tests prove that aluminium powder is perfectly suited as fuel and storage material for solar energy. The combustion product itself is again the base material for aluminium production, i.e. aluminium can be recycled. There are three problematic areas: 1. flame stability, 2. combustion duration and 3. environmental compatibility. Further development projects will aim at the construction of practice-orientated plants in which combustion, heat extraction and recovery of aluminium oxide is combined. A further aim is the melting burner to which aluminium is supplied in form of wires, cuttings or rods. (BWI).

  17. Toxicity of dissolved and precipitated aluminium to marine diatoms.

    Science.gov (United States)

    Gillmore, Megan L; Golding, Lisa A; Angel, Brad M; Adams, Merrin S; Jolley, Dianne F

    2016-05-01

    Localised aluminium contamination can lead to high concentrations in coastal waters, which have the potential for adverse effects on aquatic organisms. This research investigated the toxicity of 72-h exposures of aluminium to three marine diatoms (Ceratoneis closterium (formerly Nitzschia closterium), Minutocellus polymorphus and Phaeodactylum tricornutum) by measuring population growth rate inhibition and cell membrane damage (SYTOX Green) as endpoints. Toxicity was correlated to the time-averaged concentrations of different aluminium size-fractions, operationally defined as aluminium exposure varied between diatom species. C. closterium was the most sensitive species (10% inhibition of growth rate (72-h IC10) of 80 (55-100)μg Al/L (95% confidence limits)) while M. polymorphus (540 (460-600)μg Al/L) and P. tricornutum (2100 (2000-2200)μg Al/L) were less sensitive (based on measured total aluminium). Dissolved aluminium was the primary contributor to toxicity in C. closterium, while a combination of dissolved and precipitated aluminium forms contributed to toxicity in M. polymorphus. In contrast, aluminium toxicity to the most tolerant diatom P. tricornutum was due predominantly to precipitated aluminium. Preliminary investigations revealed the sensitivity of C. closterium and M. polymorphus to aluminium was influenced by initial cell density with aluminium toxicity significantly (paluminium toxicity to diatoms do not involve compromising the plasma membrane. These results indicate that marine diatoms have a broad range in sensitivity to aluminium with toxic mechanisms related to both dissolved and precipitated aluminium.

  18. Interstitial pulmonary disorders in indium-processing workers.

    Science.gov (United States)

    Chonan, T; Taguchi, O; Omae, K

    2007-02-01

    The production of indium-tin oxide has increased, owing to the increased manufacture of liquid-crystal panels. It has been reported that interstitial pneumonia occurred in two indium-processing workers; therefore, the present study aimed to evaluate whether interstitial pulmonary disorders were prevalent among indium workers. The study was carried out in 108 male workers in the indium plant where the two interstitial pneumonia patients mentioned above were employed, and included high-resolution computed tomography (HRCT) of the lungs, pulmonary function tests and analysis of serum sialylated carbohydrate antigen KL-6 and the serum indium concentration. Significant interstitial changes were observed in 23 indium workers on HRCT and serum KL-6 was abnormally high (>500 U x mL(-1)) in 40 workers. Workers with serum indium concentrations in the highest quartile had significantly longer exposure periods, greater HRCT changes, lower diffusing capacity of the lung for carbon monoxide and higher KL-6 levels compared with those in the lowest quartile. The serum indium concentration was positively correlated with the KL-6 level and with the degree of HRCT changes. In conclusion, the results of the present study indicated that serum KL-6 and high-resolution computed tomography abnormalities were prevalent among indium workers and that these abnormalities increased with the indium burden, suggesting that inhaled indium could be a potential cause of occupational lung disease.

  19. The oxidation and surface speciation of indium and indium oxides exposed to atmospheric oxidants

    Science.gov (United States)

    Detweiler, Zachary M.; Wulfsberg, Steven M.; Frith, Matthew G.; Bocarsly, Andrew B.; Bernasek, Steven L.

    2016-06-01

    Metallic indium and its oxides are useful in electronics applications, in transparent conducting electrodes, as well as in electrocatalytic applications. In order to understand more fully the speciation of the indium and oxygen composition of the indium surface exposed to atmospheric oxidants, XPS, HREELS, and TPD were used to study the indium surface exposed to water, oxygen, and carbon dioxide. Clean In and authentic samples of In2O3 and In(OH)3 were examined with XPS to provide standard spectra. Indium was exposed to O2 and H2O, and the ratio of O2 - to OH- in the O1s XPS region was used to monitor oxidation and speciation of the surface. HREELS and TPD indicate that water dissociates on the indium surface even at low temperature, and that In2O3 forms at higher temperatures. Initially, OH- is the major species at the surface. Pure In2O3 is also OH- terminated following water exposure. Ambient pressure XPS studies of water exposure to these surfaces suggest that high water pressures tend to passivate the surface, inhibiting extensive oxide formation.

  20. Natively textured surface hydrogenated gallium-doped zinc oxide transparent conductive thin films with buffer layers for solar cells

    International Nuclear Information System (INIS)

    Natively textured surface hydrogenated gallium-doped zinc oxide (HGZO) thin films have been deposited via magnetron sputtering on glass substrates. These natively textured HGZO thin films exhibit rough pyramid-like textured surface, high optical transmittances in the visible and near infrared region and excellent electrical properties. The experiment results indicate that tungsten-doped indium oxide (In2O3:W, IWO) buffer layers can effectively improve the surface roughness and enhance the light scattering ability of HGZO thin films. The root-mean-square roughness of HGZO, IWO (10 nm)/HGZO and IWO (30 nm)/HGZO thin films are 28, 44 and 47 nm, respectively. The haze values at the wavelength of 550 nm increase from 7.0% of HGZO thin film without buffer layer to 18.37% of IWO (10 nm)/HGZO thin film. The optimized IWO (10 nm)/HGZO exhibits a high optical transmittance of 82.18% in the visible and near infrared region (λ ∼ 400–1100 nm) and excellent electrical properties with a relatively low sheet resistance of 3.6 Ω/□ and the resistivity of 6.21 × 10−4 Ωcm. - Highlights: • Textured hydrogenated gallium-doped zinc oxide (HGZO) films were developed. • Tungsten-doped indium oxide (IWO) buffer layers were applied for the HGZO films. • Light-scattering ability of the HGZO films can be improved through buffer layers. • Low sheet resistance and high haze were obtained for the IWO(10 nm)/HGZO film. • The IWO/HGZO films are promising transparent conductive layers for solar cells

  1. Spin-phonon coupling and ferroelectricity in magnetoelectric gallium ferrite

    Science.gov (United States)

    Mukherjee, Somdutta

    2014-03-01

    Gallium ferrite (GaFeO3 or GFO) is a low temperature ferrimagnet and room temperature piezoelectric wherein the magnetic transition temperature (TC) could be tailored to room temperature and above by tuning the stoichiometry and processing conditions. Such tunability of the magnetic transition temperature renders GFO a unique perspective in the research of multiferroics to potentially demonstrate room temperature magnetoelectric effect attractive for futuristic digital memory applications. Recent studies in several transition metal oxides highlight the importance of spin-phonon coupling in designing novel multiferroics by means of strain induced phase transition. In the present work, we have systematically studied the evolution of phonons in good quality samples of GFO across the TC using Raman spectroscopy. Using the phonon softening behavior and nearest neighbor spin-spin correlation function below TC we estimated spin-phonon coupling strength in the magnetically ordered state. In the process, we also show, for the first time, the presence of a spin glass phase in GFO where the spin-glass transition has a signature of abrupt change in spin-phonon coupling strength. Though GFO is piezoelectric and crystallizes in polar Pc21n symmetry, its ferroelectric nature remained controversial probably due to the large leakage current in the bulk material. To address this issue, we deposited epitaxial thin film on single crystalline yttria stabilized zirconia (YSZ) substrate using indium tin oxide (ITO) as a bottom conducting layer. We demonstrate clear evidence of room temperature ferroelectricity in the thin films from the 180o phase shift of the piezoresponse upon switching the electric field. Further, suppression of dielectric anomaly in presence of an external magnetic field clearly reveals a pronounced magneto-dielectric coupling across the magnetic transition temperature. In addition, using first principles calculations we elucidate that Fe ions are not only

  2. Effect of aluminium phosphate as admixture on oxychloride cement

    Indian Academy of Sciences (India)

    M P S Chandrawat; R N Yadav

    2000-02-01

    The effect of admixing of aluminium phosphate on oxychloride cement in the matrix has been investigated. It is shown that aluminium phosphate retards the setting process of the cement and improves water-tightness.

  3. Structural colours and applications to anodised aluminium surfaces

    DEFF Research Database (Denmark)

    Johansen, Villads Egede

    This thesis investigates possible ways of creating aluminium with a milky white, metallic appearance for decorative purposes. Since white cannot be obtained through traditional absorption based dyeing of aluminium, optical mechanisms based on scattering by nanostructures are studied in order...

  4. Solidification of spent TBP solvent with aluminium chloride compounds

    International Nuclear Information System (INIS)

    The new techniques for processing spent TBP was investigated. It was proved that treatment of TBP containing DBP with aluminium chloride resulted in the formation of aluminium phosphate suitable for long term storage and final disposal

  5. The effect of annealing temperature on the stability of gallium tin zinc oxide thin film transistors

    International Nuclear Information System (INIS)

    With the growing need for large area display technology and the push for a faster and cheaper alternative to the current amorphous indium gallium zinc oxide (a-IGZO) as the active channel layer for pixel-driven thin film transistors (TFTs) display applications, gallium tin zinc oxide (GSZO) has shown to be a promising candidate due to the similar electronic configuration of Sn4+ and In3+. In this work TFTs of GSZO sputtered films with only a few atomic % of Ga and Sn have been fabricated. A systematic and detailed comparison has been made of the properties of the GSZO films annealed at two temperatures: 140 °C and 450 °C. The electrical and optical stabilities of the respective devices have been studied to gain more insight into the degradation mechanism and are correlated with the initial TFT performance prior to the application of stress. Post deposition annealing at 450 °C of the films in air was found to lead to a higher atomic concentration of Sn4+ in these films and a superior quality of the film, as attested by the higher film density and less surface and interface roughness in comparison to the lower annealed temperature device. These result in significantly reduced shallow and deep interface traps with improved performance of the device exhibiting VON of −3.5 V, ION/IOFF of 108, field-effect mobility (μFE) of 4.46 cm2 V−1s−1, and sub-threshold swing of 0.38 V dec−1. The device is stable under both electrical and optical bias for wavelengths of 550 nm and above. Thus, this work demonstrates GSZO-based TFTs as a promising viable option to the IGZO TFTs by further tailoring the film composition and relevant processing temperatures. (paper)

  6. Quantitative pulmonary gallium scanning in interstitial lung disease

    International Nuclear Information System (INIS)

    The mechanisms responsible for gallium uptake in chronic, non-infective, diffuse lung disease are not completely understood. This study attempted to clarify some of them. A lung/liver gallium index was calculated in 113 subjects, some normal and some with various interstitial lung diseases, predominantly those associated with connective tissue disease. The mean gallium index was significantly higher in the groups with active interstitial lung disease (5.7) and non-infective bronchiolitis (4.1) compared with non-smoking normals (3.0; P<0.05). To investigate the mechanisms responsible for gallium uptake, the gallium index was correlated with bronchoalveolar lavage findings, respiratory function tests and clinical features. Significant correlations (P<0.05) were found with age in non-smoking normals; lavage macrophages in smoking normals; age but no other parameter in bronchiolitis; lavage lymphocytes, lavage albumin and improvement in diffusion capacity for carbon monoxide in those with active interstitial lung disease. It is concluded that in normal smokers gallium uptake may be due to a macrophage-mediated process. Gallium uptake in active interstitial lung disease associated with connective tissue disease appears to be an immunological process in which transport and retention of gallium is associated with that of albumin. (orig.)

  7. Benchmarking of Evaluated Neutron Data for Gallium Sample

    Institute of Scientific and Technical Information of China (English)

    HAN; Rui; NIE; Yang-bo; RUAN; Xi-chao; BAO; Jie; REN; Jie; HUANG; Han-xiong; LI; Xia; ZHANG; Kai; ZHOU; Zu-ying

    2013-01-01

    Gallium(Ga)is a kind of target material and an important fission product.It has the characteristics of low melting point and high boiling point.The integral experimental study on Gallium data is an important issue.It has an important application for design of reactors and ADS(Accelerator Driven System)

  8. Advances in development and application of aluminium batteries

    DEFF Research Database (Denmark)

    Qingfeng, Li; Zhuxian, Qiu

    2001-01-01

    Aluminium has long attracted attention as a potential battery anode because of its high theoretical voltage and specific energy. The protective oxide layer at aluminium surface is however detrimental to its performance to achieve its reversible potential, and also causing the delayed activation o...... aluminium batteres, especially aluminium-air batteries, and a wide range of their applications from emergency power supplies, reserve batteries field portable batteries, to batteries for electric vehicles and underwater propulsion....

  9. Friction stir welding (FSW) of aluminium foam sandwich panels

    OpenAIRE

    M. Bušić; Kožuh, Z.; D. Klobčar; Samardžić, I.

    2016-01-01

    The article focuses on the influence of welding speed and tool tilt angle upon the mechanical properties at the friction stir welding of aluminium foam sandwich panels. Double side welding was used for producing butt welds of aluminium sandwich panels applying insertion of extruded aluminium profile. Such insertion provided lower pressure of the tool upon the aluminium panels, providing also sufficient volume of the material required for the weldment formation. Ultimate tensile strength and f...

  10. Thermal Plasma Synthesis of Crystalline Gallium Nitride Nanopowder from Gallium Nitrate Hydrate and Melamine

    Directory of Open Access Journals (Sweden)

    Tae-Hee Kim

    2016-02-01

    Full Text Available Gallium nitride (GaN nanopowder used as a blue fluorescent material was synthesized by using a direct current (DC non-transferred arc plasma. Gallium nitrate hydrate (Ga(NO33∙xH2O was used as a raw material and NH3 gas was used as a nitridation source. Additionally, melamine (C3H6N6 powder was injected into the plasma flame to prevent the oxidation of gallium to gallium oxide (Ga2O3. Argon thermal plasma was applied to synthesize GaN nanopowder. The synthesized GaN nanopowder by thermal plasma has low crystallinity and purity. It was improved to relatively high crystallinity and purity by annealing. The crystallinity is enhanced by the thermal treatment and the purity was increased by the elimination of residual C3H6N6. The combined process of thermal plasma and annealing was appropriate for synthesizing crystalline GaN nanopowder. The annealing process after the plasma synthesis of GaN nanopowder eliminated residual contamination and enhanced the crystallinity of GaN nanopowder. As a result, crystalline GaN nanopowder which has an average particle size of 30 nm was synthesized by the combination of thermal plasma treatment and annealing.

  11. Nuclear microprobe imaging of gallium nitrate in cancer cells

    Science.gov (United States)

    Ortega, Richard; Suda, Asami; Devès, Guillaume

    2003-09-01

    Gallium nitrate is used in clinical oncology as treatment for hypercalcemia and for cancer that has spread to the bone. Its mechanism of antitumor action has not been fully elucidated yet. The knowledge of the intracellular distribution of anticancer drugs is of particular interest in oncology to better understand their cellular pharmacology. In addition, most metal-based anticancer compounds interact with endogenous trace elements in cells, altering their metabolism. The purpose of this experiment was to examine, by use of nuclear microprobe analysis, the cellular distribution of gallium and endogenous trace elements within cancer cells exposed to gallium nitrate. In a majority of cellular analyses, gallium was found homogeneously distributed in cells following the distribution of carbon. In a smaller number of cells, however, gallium appeared concentrated together with P, Ca and Fe within round structures of about 2-5 μm diameter located in the perinuclear region. These intracellular structures are typical of lysosomial material.

  12. Nuclear microprobe imaging of gallium nitrate in cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Ortega, Richard E-mail: ortega@cenbg.in2p3.fr; Suda, Asami; Deves, Guillaume

    2003-09-01

    Gallium nitrate is used in clinical oncology as treatment for hypercalcemia and for cancer that has spread to the bone. Its mechanism of antitumor action has not been fully elucidated yet. The knowledge of the intracellular distribution of anticancer drugs is of particular interest in oncology to better understand their cellular pharmacology. In addition, most metal-based anticancer compounds interact with endogenous trace elements in cells, altering their metabolism. The purpose of this experiment was to examine, by use of nuclear microprobe analysis, the cellular distribution of gallium and endogenous trace elements within cancer cells exposed to gallium nitrate. In a majority of cellular analyses, gallium was found homogeneously distributed in cells following the distribution of carbon. In a smaller number of cells, however, gallium appeared concentrated together with P, Ca and Fe within round structures of about 2-5 {mu}m diameter located in the perinuclear region. These intracellular structures are typical of lysosomial material.

  13. Gallium-containing hydroxyapatite for potential use in orthopedics

    Energy Technology Data Exchange (ETDEWEB)

    Melnikov, P., E-mail: petrmelnikov@yahoo.com [Department of Clinical Surgery, Faculty of Medicine, Federal University of Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul (Brazil); Teixeira, A.R.; Malzac, A. [Department of Clinical Surgery, Faculty of Medicine, Federal University of Mato Grosso do Sul, Campo Grande, Mato Grosso do Sul (Brazil); Coelho, M. de B. [Brazilian Agricultural Research Corporation - EMBRAPA (Brazil)

    2009-09-15

    A novel material that may be recommended for grafts and implants stimulating bone growth has been obtained by introducing gallium ions (up to 11.0 mass%) into crystalline lattice of hydroxyapatite. The doping was carried out using gallium nitrate and sodium gallate solutions. In both cases, lattice parameters of gallium-doped hydroxyapatite are identical to those of pure synthetic hydroxyapatite. Gallium does not replace calcium as a result of heterovalent substitution and consequently produces no distortions in the framework of hydroxyapatite matrix. It remains strongly fixed in the form of solid solution of intercalation. According to scanning electron microscopy images gallium insertion does not cause any morphological alterations in hydroxyapatite structure and the product developed meets physico-chemical criteria for biomaterial to be employed in orthopedic practice and local handling of traumatic injuries. Its future usage opens the opportunity to enhance osteosynthesis and calcium retention in loco.

  14. Aluminium allergy and granulomas induced by vaccinations for children

    DEFF Research Database (Denmark)

    Andersen, Rosa Marie O; Zachariae, Claus; Johansen, Jeanne Duus

    2014-01-01

    Vaccination with aluminium-adsorbed vaccines can induce aluminium allergy with persistent itching subcutaneous nodules at the injection site - vaccination granulomas. In this article we give an overview of childhood aluminium-adsorbed vaccines available in Denmark. Through literature studies we...... examine the incidence, the symptoms and the prognosis for the vaccination granulomas and the allergy. Finally we discuss the status in Denmark....

  15. Stability of aluminium beams in case of fire

    NARCIS (Netherlands)

    Meulen, O.R. van der; Soetens, F.; Maljaars, J.

    2014-01-01

    Fire is often the dominant design criterion for aluminium structures. Present design rules for aluminium constructions in fire neglect both the decrease in susceptibility to local buckling and the effects of creep, that are intrinsic to aluminium. They may therefore either overestimate or underestim

  16. Energy Absorption of Monolithic and Fibre Reinforced Aluminium Cylinders

    NARCIS (Netherlands)

    De Kanter, J.L.C.G.

    2006-01-01

    Summary accompanying the thesis: Energy Absorption of Monolithic and Fibre Reinforced Aluminium Cylinders by Jens de Kanter This thesis presents the investigation of the crush behaviour of both monolithic aluminium cylinders and externally fibre reinforced aluminium cylinders. The research is based

  17. Qimingxing Aluminium of Jinma Group Ceases Production

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    <正>Jinma Group announced on December 23 that its subsidiary Meishan Qimingxing Aluminium decided to cease production starting from De- cember 23,and that the company will keep a close eye to the market and will resume pro- duction once the market bounces back.In 2007, Jinma Group took over Meishan Qimingxing’s 40% share by 112 million yuan to enter the aluminium industry.Meishan Qimingxing’s assets include a 125,000-ton production line of aluminium and 168 300KA electrolytic baths. Affected by the state’s macro-regulation policy in early years,the company’s profit fell short of estimates.Net profit of Meishan Qimingxing in 2007 was 10.65 million yuan.

  18. Diamond grooving of rapidly solidified optical aluminium

    Science.gov (United States)

    Abou-El-Hossein, Khaled; Hsu, Wei-Yao; Ghobashy, Sameh; Cheng, Yuan-Chieh; Mkoko, Zwelinzima

    2015-10-01

    Traditional optical aluminium grades such as Al 6061 are intensively used for making optical components for applications ranging from mould insert fabrication to laser machine making. However, because of their irregular microstructure and relative inhomogeneity of material properties at micro scale, traditional optical aluminium may exhibit some difficulties when ultra-high precision diamond turned. Inhomogeneity and micro-variation in the material properties combined with uneven and coarse microstructure may cause unacceptable surface finish and accelerated tool wear, especially in grooving operation when the diamond tool edge is fully immersed in the material surface. Recently, new grades of optical aluminium that are featured by their ultra-fine microstructure and improved material properties have been developed to overcome the problem of high tool wear rates. The new aluminium grades have been developed using rapid solidification process which results in extremely small grain sizes combined with improved mechanical properties. The current study is concerned with investigating the performance of single-point diamond turning when grooving two grades of rapidly solidified aluminium (RSA) grades: RSA905 which is a high-alloyed aluminium grade and RSA443 which has a high silicon content. In this study, two series of experiments employed to create radial microgrooves on the two RSA grades. The surface roughness obtained on the groove surface is measured when different combinations of cutting parameters are used. Cutting speed is varied while feed rate and depth of cut were kept constant. The results show that groove surface roughness produced on RSA443 is higher than that obtained on RSA905. Also, the paper reports on the effect of cutting speed on surface roughness for each RSA grade.

  19. New aluminium alloys with high lithium content

    Energy Technology Data Exchange (ETDEWEB)

    Schemme, K.; Velten, B.

    1989-06-01

    Since the early 80's there have been made great efforts to replace the high strength aluminium alloys for the aircraft and space industry by a new generation of aluminium-lithium alloys. The attractivity of this kind of alloys could be increased by a further reduction of their density, caused by an increasing lithium content (/ge/ 5 wt.% Li). Therefore binary high-lithium containing alloys with low density are produced and metallografically investigated. A survey of their strength and wear behavior is given by using tensile tests and pin abrasing tests. (orig.).

  20. Indium-111 autologous leukocyte imaging in pancreatitis

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, J.R.; Spence, R.A.; Laird, J.D.; Ferguson, W.R.; Kennedy, T.L.

    1986-03-01

    Thirty-nine patients with acute pancreatitis have been assessed using a prognostic factor grading system, abdominal ultrasound, and autologous leukocyte imaging. Both prognostic factor grading and leukocyte imaging can accurately assess the severity of the disease early in its course. All patients with a negative indium-labeled leukocyte image recovered without sequelae, whereas five of the 12 patients with a positive image developed complications, including two deaths. Abdominal ultrasound is of no value in assessing severity, but is a useful method of detecting those patients with gallstone-associated disease. In patients with suspected abscess formation following acute pancreatitis, indium leukocyte imaging does not differentiate between fat necrosis and abscess formation. In this situation, computerized tomography should be carried out before laparotomy is undertaken.

  1. China’s Aluminium Consumption and the Related Policies

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    <正>China is a major aluminium consumer country in the world. In 2005, China produced 7.81 million tons aluminium and imported 640,000 tons. Meanwhile, China also exported 1.32 million tons aluminium in 2005. China’s apparent consumption of aluminium in 2005 was about 7.1 million tons, which was 9.3 times over that in 1990. China’s aluminium consumption growth has kept at an annual average of 16.1 per cent since 1990, which makes China the

  2. China’s Production and Market of Aluminium Extruded Profiles

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>Chinese aluminium extrusion industry came into existence at the early 1950s with most products used in military industry and national defence.At the beginning of 1980s,the produc- tion of construction aluminium profiles started simultaneously in North and South China.In the following thirty years,the aluminium extru- sion industry entered into a quickly developing stage with a focus on construction aluminium profiles.With the blooming real estate industry, the demand for construction aluminium profiles from the domestic market has a tendency of yearly increase.From 2000,the quick devel- opments of China’s auto and railway vehicle

  3. Irradiation damage in aluminium single crystals produced by 50-keV aluminium and copper ions

    DEFF Research Database (Denmark)

    Henriksen, L.; Johansen, A.; Koch, J.;

    1968-01-01

    Aluminium single crystals, thin enough to be examined by electron microscopy, have been irradiated with 50-keV aluminium and copper ions. The irradiation fluxes were in the range 1011–1014 cm−2 s−1 and the doses were from 6 × 1012 to 6 × 1014 cm−2. Irradiation along either a or a direction produces...... rows of dislocation loops all lying parallel to one particular direction. If the aluminium target is quenched from 600 °C and annealed at room temperature prior to irradiation with aluminium ions, the rows of loops are suppressed. The amount of damage observed is considerably less than would...

  4. Indium Antimonide Nanowires: Synthesis, Characterization, and Applications

    OpenAIRE

    Penchev, Miroslav Valentinov

    2012-01-01

    Indium Antimonide (InSb) nanowires with a diameter ranging from 30 nm to 200 nm, were synthesized by electrochemical disposition in anodized alumina and polycarbonate porous membranes. In addition, epitaxial single crystalline InSb nanowires with diameters ranging from 5 nm to 100 nm, were synthesized by chemical vapor deposition (CVD) using Au nanoparticles as catalyst. Structural and material characterization of InSb nanowires was carried out by scanning electron microscopy (SEM), energy di...

  5. Recovery of indium and lead from lead bullion

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Lead and indium were recovered by electrolysis and nonequilibrium solvent extraction process from lead bullion.The effects of current density,electrolytic period and circle amnant of electrolyte on the electrochemical dissolution of lead and indium were investigated.The effects of extraction phase ratio and mixing time on solvent extraction of indium and striping phase ratio and stripping stage on the loaded organic phase stripping were also investigated.The experimental results indicate that under optimum conditions,the purity of lead deposited on cathode is 98.5% and the deposit rate of lead is 99.9%,the dissolution rate of indium is 94.28%,the extraction rate of indium is 98.69%,the stripping rate of indium is almost 100%,and the impurity elements,such as Zn,Fe and Sn can be removed.

  6. Aluminium composite casting dispersion reinforced with iron-aluminium and silicon carbide phases

    OpenAIRE

    B. Formanek; J. Piątkowski; J. Szymszal

    2010-01-01

    Aluminium matrix composite with dispersion-reinforced, made by similar to stircasting process was characterised. The mixture of powders was produced by the process of mechanical agglomeration of powdered FexAly and SiC with aluminium. The chemical composition ofagglomerates was selected in a way such as to obtain 25 wt.% reinforcement of the AlSi9Cu4 silumin matrix. Applying thermal analysis ATD, the alloy solidification process was determined, reading out the typical solidification parameter...

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

    Science.gov (United States)

    Yoo, Myoung Han; Kim, Nam-Hoon

    2016-05-01

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

  8. Study on indium leaching from mechanically activated hard zinc residue

    OpenAIRE

    Yao J.H.; Li X.H.; Li Y.W.

    2011-01-01

    In this study, changes in physicochemical properties and leachability of indium from mechanically activated hard zinc residue by planetary mill were investigated. The results showed that mechanical activation increased specific surface area, reaction activity of hard zinc residue, and decreased its particle size, which had a positive effect on indium extraction from hard zinc residue in hydrochloric acid solution. Kinetics of indium leaching from unmilled and activated hard zinc residue...

  9. Compatibility of ITER candidate structural materials with static gallium

    Energy Technology Data Exchange (ETDEWEB)

    Luebbers, P.R.; Michaud, W.F.; Chopra, O.K.

    1993-12-01

    Tests were conducted on the compatibility of gallium with candidate structural materials for the International Thermonuclear Experimental Reactor, e.g., Type 316 SS, Inconel 625, and Nb-5 Mo-1 Zr alloy, as well as Armco iron, Nickel 270, and pure chromium. Type 316 stainless steel is least resistant to corrosion in static gallium and Nb-5 Mo-1 Zr alloy is most resistant. At 400{degrees}C, corrosion rates are {approx}4.0, 0.5, and 0.03 mm/yr for type 316 SS, Inconel 625, and Nb-5 Mo- 1 Zr alloy, respectively. The pure metals react rapidly with gallium. In contrast to findings in earlier studies, pure iron shows greater corrosion than nickel. The corrosion rates at 400{degrees}C are {ge}88 and 18 mm/yr, respectively, for Armco iron and Nickel 270. The results indicate that at temperatures up to 400{degrees}C, corrosion occurs primarily by dissolution and is accompanied by formation of metal/gallium intermetallic compounds. The solubility data for pure metals and oxygen in gallium are reviewed. The physical, chemical, and radioactive properties of gallium are also presented. The supply and availability of gallium, as well as price predictions through the year 2020, are summarized.

  10. Molecular breeding of cereals for aluminium resistance

    Science.gov (United States)

    Aluminium (Al3+) toxicity is the primary factor limiting crop production on acidic soils worldwide. In addition to an application of lime for soil amelioration, Al3+ resistant plant varieties have been deployed to raise productivity on such hostile soils. This has been possible due to the exploita...

  11. Experimental analysis of cut welding in aluminium

    DEFF Research Database (Denmark)

    Dorph, Pernille; De Chiffre, Leonardo; Bay, Niels

    1993-01-01

    Cut welding is a newly developed cold pressure welding process. In the present work, an experimental investigation was carried out analyzing the mechanisms involved in cut welding of a block to a strip. Experiments were carried out in technically pure aluminium. The investigation has involved...

  12. Aluminium hydroxide-induced granulomas in pigs

    DEFF Research Database (Denmark)

    Valtulini, S; Macchi, C; Ballanti, P;

    2005-01-01

    in the muscles of the neck (group slaughtered). The pigs had been injected with a vaccine containing 40 mg/2 ml dose of aluminium hydroxide as adjuvant. Research consisted of two phases: first, an epidemiological study was carried out, aimed at determining the risk factors for the granulomas. The results...

  13. Indentation of aluminium foam at low velocity

    Directory of Open Access Journals (Sweden)

    Shi Xiaopeng

    2015-01-01

    Full Text Available The indentation behaviour of aluminium foams at low velocity (10 m/s ∼ 30 m/s was investigated both in experiments and numerical simulation in this paper. A flat-ended indenter was used and the force-displacement history was recorded. The Split Hopkinson Pressure bar was used to obtain the indentation velocity and forces in the dynamic experiments. Because of the low strength of the aluminium foam, PMMA bar was used, and the experimental data were corrected using Bacon's method. The energy absorption characteristics varying with impact velocity were then obtained. It was found that the energy absorption ability of aluminium foam gradually increases in the quasi-static regime and shows a significant increase at ∼10 m/s velocity. Numerical simulation was also conducted to investigate this process. A 3D Voronoi model was used and models with different relative densities were investigated as well as those with different failure strain. The indentation energy increases with both the relative density and failure strain. The analysis of the FE model implies that the significant change in energy absorption ability of aluminium foam in indentation at ∼10 m/s velocity may be caused by plastic wave effect.

  14. Microstructure Development during Solidification of Aluminium Alloys

    NARCIS (Netherlands)

    Ruvalcaba Jimenez, D.G.

    2009-01-01

    This Thesis demonstrates studies on microstructure development during the solidification of aluminium alloys. New insights of structure development are presented here. Experimental techniques such as quenching and in-situ High-brilliance X-ray microscopy were utilized to study the microstructure evo

  15. New indium selenite-oxalate and indium oxalate with two- and three-dimensional structures

    International Nuclear Information System (INIS)

    Two new indium(III) compounds with extended structures, [In2(SeO3)2(C2O4)(H2O)2].2H2O (I) and [NH3(CH2)2NH3][In(C2O4)2]2.5H2O (II), have been prepared under mild hydrothermal conditions and structurally characterized by single-crystal X-ray diffraction, thermogravimetric analysis and infrared spectroscopy. Compound I crystallizes in the triclinic system, space group P-1, with a=5.2596(11) A, b=6.8649(14) A, c=9.3289(19) A, α=101.78(3)o, β=102.03(3)o, γ=104.52(3)o, while compound II crystallizes in the orthorhombic system, space group Fdd2, with a=15.856(3) A, b=31.183(6) A, c=8.6688(17) A. In compound I, indium-selenite chains are bridged by oxalate units to form two-dimensional (2D) In2(SeO3)2C2O4 layers, separated by non-coordinating water molecules. In compound II, the indium atoms are connected through the oxalate units to generate a 3D open framework containing cross-linked 12- and 8-membered channels. - Graphical abstract: Two new indium(III) compounds have been hydrothermally synthesized and structurally characterized. In I, the indium-selenite chains are bridged by oxalate units to form 2D In2(SeO3)2C2O4 layers. In II, the indium atoms are connected through the oxalate units to generate a 3D open framework containing cross-linked 12- and 8-membered ring channels

  16. Subclinical interstitial lung damage in workers exposed to indium compounds

    OpenAIRE

    Choi, Sungyeul; Won, Yong-Lim; Kim, Dohyung; Yi, Gwang-Yong; Park, Jai-Soung; Kim, Eun-A

    2013-01-01

    Objectives The present study was designed to determine whether there is a relationship between indium compound exposure and interstitial lung damage in workers employed at indium tin oxide manufacturing and reclaiming factories in Korea. Methods In 2012, we conducted a study for the prevention of indium induced lung damage in Korea and identified 78 workers who had serum indium or Krebs von den Lungen-6 (KL-6) levels that were higher than the reference values set in Japan (3 μg/L and 500 U/mL...

  17. Preparation for Ultra High Pure Indium Metal for Optoelectronic Applications

    Directory of Open Access Journals (Sweden)

    Shashwat V. Joshi

    2014-11-01

    Full Text Available Ultra high pure Indium metal is extensively used in optoelectronic devices. Indium and its alloys become potential candidates in aerospace, defense and communication sectors. Purification of Indium has been done by Instrolec-200 Refiner followed by Directional Melting/ Freezing and Solidification Systems. Major targeted impurities are Metallic impurities Ag, Al, As, Bi, Ca, Cu, Fe, Ga, Ge, Mg, Pb, Sb, Si, Sn, and Zn. Purified Indium is characterized by analytical techniques Inductively Coupled Plasma- Optical Emission Spectrophotometry and Inductively Coupled Plasma- Mass Spectrometry.

  18. Thoracic gallium uptake in patients with lymphomatoid granulomatosis

    International Nuclear Information System (INIS)

    Lymphomatoid granulomatosis (LG) is a rare condition with histological similarities to Wegener's granulomatosis and malignant lymphoma. Characteristically there is an angiocentric, angiodestructive lymphoreticular cell infiltrate. The lungs are usually affected, and, less frequently, the skin, nervous system, kidney, and bowel are involved. The prognosis is poor and frank lymphoma develops, in some cases terminally. The usual radiological appearance of the lungs consists of bilateral nodular lower zone opacities. The authors report two patients (siblings) with LG, and their gallium scans are presented. In each case there was a significant accumulation of gallium in the lungs at times of clinically active disease. The limited role of gallium imaging in this disease is discussed

  19. Measurement of the solar neutrino capture rate with gallium metal

    CERN Document Server

    Abdurashitov, J N; Girin, S V; Gorbachev, V V; Ibragimova, T V; Kalikhov, A V; Khairnasov, N G; Knodel, T V; Mirmov, I N; Shikhin, A A; Veretenkin, E P; Vermul, V M; Yants, V E; Zatsepin, G T; Bowles, T J; Teasdale, W A; Wark, D L; Cherry, M L; Nico, J S; Cleveland, B T; Davis, R; Lande, K; Wildenhain, P S; Elliott, S R; Wilkerson, J F

    1999-01-01

    The solar neutrino capture rate measured by the Russian-American Gallium Experiment (SAGE) on metallic gallium during the period January 1990 through December 1997 is 67.2 (+7.2-7.0) (+3.5-3.0) SNU, where the uncertainties are statistical and systematic, respectively. This represents only about half of the predicted Standard Solar Model rate of 129 SNU. All the experimental procedures, including extraction of germanium from gallium, counting of 71Ge, and data analysis are discussed in detail.

  20. Reduction of metallic ions by molten gallium under ultrasonic irradiation and interactions between the formed metals and the gallium

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Vijay Bhooshan; Perelshtein, Ilana [Bar-Ilan Institute for Nanotechnology and Advanced Materials, Department of Chemistry, Bar-Ilan University, Ramat-Gan 52900 (Israel); Kimmel, Giora [Institute of Applied Research, Ben-Gurion University of the Negev, Be’er Sheva 84105 (Israel); Porat, Ze’ev [Institute of Applied Research, Ben-Gurion University of the Negev, Be’er Sheva 84105 (Israel); Division of Chemistry, Nuclear Research Center-Negev, Be’er Sheva 84190 (Israel); Gedanken, Aharon, E-mail: gedanken@mail.biu.ac.il [Bar-Ilan Institute for Nanotechnology and Advanced Materials, Department of Chemistry, Bar-Ilan University, Ramat-Gan 52900 (Israel); National Cheng Kung University, Department of Materials Science & Engineering, Tainan 70101, Taiwan (China)

    2015-07-15

    Graphical abstract: The XRD pattern and electron microscopy images of the product obtained by the reduction solution of CuSO{sub 4} by the molten Ga under ultrasonic wave. CuGa{sub 2} clearly obtained from the reaction. - Highlights: • Effect of ultrasonic cavitation and heterogeneous reduction in binary systems. • Dispersion of gallium into microparticles enhances tremendously the reduction rate. • The sonochemical reduction by Ga forms intermetallic like Ag{sub 2}Ga, CuGa{sub 2} and AuGa{sub 2}. - Abstract: Metallic gallium can reduce ions of silver, copper or gold in a slow spontaneous reaction to form the free metals. However, when the reduction is performed with molten gallium under ultrasonic irradiation, the gallium is dispersed into micrometric spheres and the reduction rate is enhanced dramatically. This is due to the large surface area of unoxidized gallium that is formed, on which the heterogeneous reduction occurs. Each of these metals formed also a certain amount of an intermetallic compound with the gallium: Ag{sub 2}Ga, CuGa{sub 2} and AuGa{sub 2}. Zinc has a more negative reduction potential than gallium and therefore no reduction of zinc ions was expected. Nevertheless we conducted an experiment using a solution of zinc ions to check whether the extremely high temperature that develops near the surface of the particles during cavitation can overcome the energetic barrier for such reduction.

  1. A STUDY ON THE BEHAVIOUR OF GALLIUM IN THE IRONMAKING PROCESS

    Institute of Scientific and Technical Information of China (English)

    L. Savov; S. Garonin; O. Ivanov; Y.S. Yusfin; D. Janke

    2003-01-01

    Gallium is a valuable rare metal which is mainly being used in the production of GaAs.The demand for gallium is increasing but production is limited since gallium is ex-tracted only as a by-product of bauxite processing. On the other hand coal, ironmakingcoke and iron ore gangue contain traces of gallium. However little is known about thebehaviour of gallium in ironmaking. The aim of the study is to clarify the distributionof gallium between hot metal, slag and top gas by means of laboratory experiments. Itwas found that Ga2 O3 is not stable in blast furnace slags and that gallium is retainedin hot metal. Vacuum distillation experiments with hot metal showed that galliumis not transferred to the gas phase. Data on the input and output of gallium at twoindustrial blast furnaces, as well as chemical analyses of the gallium content of severalcokes are presented, too.

  2. Role of indium-111 white blood cells in inflammatory bowel disease

    Energy Technology Data Exchange (ETDEWEB)

    Froelich, J.W.; Field, S.A.

    1988-10-01

    Inflammatory bowel disease in patients may be difficult to diagnose because of the complex problems associated with this disease. Radionuclides are able to provide a rapid and effective method of imaging the bowel in patients with active inflammatory bowel disease. In the past, clinical work-ups have included barium x-ray studies and endoscopy. Scarring and fistula formation have made it difficult to determine between the active disease and abscesses that may occur. Gallium-67 (67Ga) has been very useful in imaging patients with inflammatory bowel disease, but the multiple-day imaging procedure has been a limitation for the clinicians when achieving a diagnosis. Recent results with Indium-111 (111In)--labeled WBCs have provided excellent correlation between clinical symptoms and colonoscopy findings in patients with inflammatory bowel disease. This technique has also allowed the differentiation between reoccurring inflammatory bowel disease and abscesses that accompany the disease within a 24-hour time period. The use of intravenous (IV) glucagon has increased the clarity of the images in the small bowel. Technetium 99m (99mTc) diethylenetriaminepentaacetic acid (DTPA) has been used in patients with inflammatory bowel disease demonstrating promising results. Investigators feel labelling 99mTc with WBCs will be improved, therefore yielding a greater efficiency, which will have a major impact on imaging patients with inflammatory bowel disease. Imaging patients with inflammatory bowel disease using radionuclides has yielded promising results. This is a significant advancement over barium radiography and endoscopy exams.24 references.

  3. The effect of copper and gallium compounds on ribonucleotide reductase

    Energy Technology Data Exchange (ETDEWEB)

    Narasimhan, J.

    1992-01-01

    The mode of action of copper complexes (CuL and CuKTS) and gallium compounds (gallium nitrate and citrate) in cytotoxicity was studied. The effects of these agents on the enzyme ribonucleotide reductase was investigated by monitoring the tyrosyl free radical present in the active site of the enzyme through electron spin resonance (ESR) spectroscopy. Ribonucleotide reductase, a key enzyme in cellular proliferation, consists of two subunits. M1, a dimer of molecular weight 170,000 contains the substrate and effector binding sites. M2, a dimer of molecular weight 88,000, contains non-heme iron and tyrosyl free radical essential for the activity of the enzyme. In studies using copper complexes, the cellular oxidative chemistry was examined by ESR studies on adduct formation with membranes, and oxidation of thiols. Membrane thiols were oxidized through the reduction of the ESR signal of the thiol adduct and the analysis of sulfhydryl content. Using the radiolabel [sup 59]Fe, the inhibitory action of copper thiosemicarbazones on cellular iron uptake was shown. The inhibitory action of CuL on ribonucleotide reductase was shown by the quenching of the tyrosyl free radical on the M2 subunit. The hypothesis that gallium directly interacts with the M2 subunit of the enzyme and displaces the iron from it was proven. The tyrosyl free radical signal from cell lysates was inhibited by the direct addition of gallium compounds. Gallium content in the cells was measured by a fluorimetric method, to ensure the presence of sufficient amounts of gallium to compete with the iron in the M2 subunit. The enzyme activity, measured by the conversion of [sup 14]C-CDP to the labeled deoxy CDP, was inhibited by the addition of gallium nitrate in a cell free assay system. The immunoprecipitation studies of the [sup 59]Fe labeled M2 protein using the monoclonal antibody directed against this subunit suggested that gallium releases iron from the M2 subunit.

  4. The status of the Soviet-American gallium neutrino experiment

    Energy Technology Data Exchange (ETDEWEB)

    Abazov, A.I.; Abdurashitov, D.N.; Anosov, O.L.; Bychuk, O.V.; Danshin, S.N.; Eroshkina, L.A.; Faizov, E.L.; Gavrin, V.N.; Gayevsky, V.I.; Girin, S.V.; Kalikhov, A.V.; Kireyev, S.M.; Knodel, T.V.; Knyshenko, I.I.; Kornoukhov, V.N.; Mezentseva, S.A.; Mirmov, I.N.; Ostrinsky, A.I.; Petukhov, V.V.; Pshukov, A.M.; Revzin, N.Ye.; Shikhin, A.A.; Slyusareva, Ye.D.; Tikhonov, A.A.; Timofeyev, P.V.; Veretenkin, E.P.; Vermul, V.M.; Yantz, V.E.; Zakharov, Yu.; Zatsepin, G.T.; Zhandarov, V.I. [AN SSSR, Moscow (USSR). Inst. Yadernykh Issledovanij; Bowles, T.J.; Cleveland, B.T.; Elliott, S.R.; O`Brien, H.A.; Wark, D.L.; Wilkerson, J.F. [Los Alamos National Lab., NM (United States); Davis, R. Jr.; Lande, K. [Pennsylvania Univ., Philadelphia (United States); Kouzes, R.T. [Princeton Univ., NJ (United States); Cherry, M.L.; SAGE Collaboration

    1990-02-01

    A radiochemical {sup 71}Ga-{sup 71}Ge experiment to determine the integral flux of neutrinos from the sun has been constructed at the Baksan Neutrino Observatory in the USSR. Measurements have begun with 30 tonnes of gallium. An additional 30 tonnes of gallium are being installed so as to perform the full experiment with a 60 tonne target. The motivation, experimental procedures, and present status of this experiment are described. (orig.).

  5. Raman study of gallium selenide single crystal oxidation

    Directory of Open Access Journals (Sweden)

    O.A. Balitskii

    2001-06-01

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

  6. Gallium Nitride Room Temperature α Particle Detectors

    International Nuclear Information System (INIS)

    Gallium Nitride (GaN) room temperature α particle detectors are fabricated and characterized, whose device structure is Schottky diode. The current-voltage (I – V) measurements reveal that the reverse breakdown voltage of the detectors is more than 200 V owing to the consummate fabrication processes, and that the Schottky barrier and ideal factor of the detectors are 0.64 eV and 1.02, respectively, calculated from the thermionic transmission model. 241Am α particles pulse height spectra from the GaN detectors biased at −8 V is obviously one Gauss peak located at channel 44 with the full width at half maximum (FWHM) of 15.87 in channel. One of the main reasons for the relatively wider FWHM is that the air between the detectors and isotope could widen the spectrum

  7. Gallium-Catalyzed Silicon Oxide Nanowire Growth

    Institute of Scientific and Technical Information of China (English)

    Zheng Wei Pan; Sheng Dai; Douglas H.Lowndes

    2005-01-01

    Silicon oxide nanowires tend to assemble into various complex morphologies through a metalcatalyzed vapor-liquid-solid (VLS) growth process. This article summarizes our recent efforts in the controlled growth of silicon oxide nanowire assemblies by using molten gallium as the catalyst and silicon wafer,SiO powder, or silane (SiH4) as the silicon sources. Silicon oxide nanowire assemblies with morphologies of carrotlike, cometlike, gourdlike, spindlelike, badmintonlike, sandwichlike, etc. were obtained. Although the morphologies of the nanowire assemblies are temperature- and silicon source-dependent, they share similar structural and compositional features: all the assemblies contain a microscale spherical liquid Ga ball and a highly aligned, closely packed amorphous silicon oxide nanowire bunch. The Ga-catalyzed silicon oxide nanowire growth reveals several interesting new nanowire growth phenomena that expand our knowledge of the conventional VLS nanowire growth mechanism.

  8. Cavity optomechanics in gallium phosphide microdisks

    CERN Document Server

    Mitchell, Matthew; Barclay, Paul E

    2013-01-01

    Gallium phosphide microdisk optical microcavities with intrinsic quality factors > 280,000 and mode volumes < (10 lambda/n)^3 are demonstrated, and their nonlinear and optomechanical properties are studied. For optical intensities up to 350,000 intracavity photons, optical loss within the microcavity is observed to decrease with increasing intensity, indicating that saturable absorption sites are present in the GaP material, and that two photon absorption is not significant. Optomechanical coupling between several mechanical resonances and the optical modes of the microdisk is observed, and an optical spring effect consistent with a theoretically predicted optomechanical coupling rate g_0~80 kHz is measured for the 488 MHz mechanical fundamental radial breathing mode.

  9. Gallium arsenide solar array subsystem study

    Science.gov (United States)

    Miller, F. Q.

    1982-01-01

    The effects on life cycle costs of a number of technology areas are examined for a gallium arsenide space solar array. Four specific configurations were addressed: (1) a 250 KWe LEO mission - planer array; (2) a 250 KWe LEO mission - with concentration; (3) a 50 KWe GEO mission planer array; (4) a 50 KWe GEO mission - with concentration. For each configuration, a baseline system conceptual design was developed and the life cycle costs estimated in detail. The baseline system requirements and design technologies were then varied and their relationships to life cycle costs quantified. For example, the thermal characteristics of the baseline design are determined by the array materials and masses. The thermal characteristics in turn determine configuration, performance, and hence life cycle costs.

  10. Selective separation of indium by iminodiacetic acid chelating resin

    Energy Technology Data Exchange (ETDEWEB)

    Fortes, M.C.B.; Benedetto, J.S. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Martins, A.H. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Metalurgica e de Materiais]. E-mail: ahmartin@demet.ufmg.br

    2007-04-15

    - Indium can be recovered by treating residues, flue dusts, slags, and metallic intermediates in zinc smelting. This paper investigates the adsorption characteristics of indium and iron on an iminodiacetic acid chelating resin, Amberlite{sup R} IRC748 (Rohm and Haas Co.-USA). High concentrations of iron are always present in the aqueous feed solution of indium recovery. In addition, the chemical behaviour of iron in adsorptive systems is similar to that of indium. The metal concentrations in the aqueous solution were based on typical indium sulfate leach liquor obtained from zinc hydrometallurgical processing in a Brazilian plant. The ionic adsorption experiments were carried out by the continuous column method. Amberlite{sup R} IRC748 resin had a high affinity for indium under acidic conditions. Indium ions adsorbed onto the polymeric resin were eluted with a 0.5 mol/dm{sup 3} sulphuric acid solution passed through the resin bed in the column. 99.5% pure indium sulfate aqueous solution was obtained using the iminodiacetic acid chelating resin Amberlite{sup R} IRC748. (author)

  11. Gallium Nitride Schottky betavoltaic nuclear batteries

    International Nuclear Information System (INIS)

    Research highlights: → Gallium Nitride nuclear batteries with Ni-63 are demonstrated for the first time. → Open circuit voltage of 0.1 V and conversion efficiency of 0.32% have been obtained. → The limited performance is due to thin effective energy deposition layer. → The output power is expected to greatly increase with growing thick GaN films. -- Abstract: Gallium Nitride (GaN) Schottky betavoltaic nuclear batteries (GNBB) are demonstrated in our work for the first time. GaN films are grown on sapphire substrates by metalorganic chemical vapor deposition (MOCVD), and then GaN Schottky diodes are fabricated by normal micro-fabrication process. Nickel with mass number of 63 (63Ni), which emits β particles, is loaded on the GaN Schottky diodes to achieve GNBB. X-ray diffraction (XRD) and photoluminescence (PL) are carried out to investigate the crystal quality for the GaN films as grown. Current-voltage (I-V) characteristics shows that the GaN Schottky diodes are not jet broken down at -200 V due to consummate fabrication processes, and the open circuit voltage of the GNBB is 0.1 V and the short circuit current density is 1.2 nA cm-2. The limited performance of the GNBB is due to thin effective energy deposition layer, which is only 206 nm to absorb very small partial energy of the β particles because of the relatively high dislocation density and carrier concentration. However, the conversion efficiency of 0.32% and charge collection efficiency (CCE) of 29% for the GNBB have been obtained. Therefore, the output power of the GNBB are expected to greatly increase with growing high quality thick GaN films.

  12. Handling characteristics of gallium alloy for dental restoration.

    Science.gov (United States)

    Mash, L K; Miller, B H; Nakajima, H; Collard, S M; Guo, I Y; Okabe, T

    1993-12-01

    The handling characteristics of a gallium alloy (Gallium Alloy GF) were compared to those of a spherical high-copper amalgam (Tytin). Ten dentists each restored four identical MO preparations in acrylic typodont teeth (no. 30), two with amalgam and two with gallium alloy. Each restoration was evaluated immediately following completion by the operator for six clinically relevant criteria. Each criterion was scored between 1 and 5, where 1 = very poor, 2 = poor, 3 = fair, 4 = good, and 5 = very good. Three two-sided Mann-Whitney tests were used to compare the median scores for significant differences (P < 0.05). The first test indicated no significant difference between scores for the first- and second-placed restorations, within criteria and within alloy type (n = 10). The second test indicated a significant difference between amalgam and gallium alloy, within criteria and within restoration sequence (n = 10), for each criterion except resistance to fracture during removal of the matrix band. The third test indicated a significant difference between amalgam and gallium alloy, within each criteria, combining scores for first- and second-placed restorations (n = 20). During simulated clinical placement, amalgam was rated significantly higher than gallium alloy in each handling characteristic evaluated.

  13. Inhalation developmental toxicology studies: Gallium arsenide in mice and rats

    Energy Technology Data Exchange (ETDEWEB)

    Mast, T.J.; Greenspan, B.J.; Dill, J.A.; Stoney, K.H.; Evanoff, J.J.; Rommereim, R.L.

    1990-12-01

    Gallium arsenide is a crystalline compound used extensively in the semiconductor industry. Workers preparing solar cells and gallium arsenide ingots and wafers are potentially at risk from the inhalation of gallium arsenide dust. The potential for gallium arsenide to cause developmental toxicity was assessed in Sprague- Dawley rats and CD-1 (Swiss) mice exposed to 0, 10, 37, or 75 mg/m{sup 3} gallium arsenide, 6 h/day, 7 days/week. Each of the four treatment groups consisted of 10 virgin females (for comparison), and {approx}30 positively mated rats or {approx}24 positively mated mice. Mice were exposed on 4--17 days of gestation (dg), and rats on 4--19 dg. The day of plug or sperm detection was designated as 0 dg. Body weights were obtained throughout the study period, and uterine and fetal body weights were obtained at sacrifice (rats, 20 dg; mice, 18 dg). Implants were enumerated and their status recorded. Live fetuses were sexed and examined for gross, visceral, skeletal, and soft-tissue craniofacial defects. Gallium and arsenic concentrations were determined in the maternal blood and uterine contents of the rats (3/group) at 7, 14, and 20 dg. 37 refs., 11 figs., 30 tabs.

  14. Fabrication, structure and mechanical properties of indium nanopillars

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Gyuhyon; Kim, Ju-Young; Budiman, Arief Suriadi; Tamura, Nobumichi; Kunz, Martin; Chen, Kai; Burek, Michael J.; Greer, Julia R.; Tsui, Ting Y.

    2010-01-01

    Solid and hollow cylindrical indium pillars with nanoscale diameters were prepared using electron beam lithography followed by the electroplating fabrication method. The microstructure of the solid-core indium pillars was characterized by scanning micro-X-ray diffraction, which shows that the indium pillars were annealed at room temperature with very few dislocations remaining in the samples. The mechanical properties of the solid pillars were characterized using a uniaxial microcompression technique, which demonstrated that the engineering yield stress is {approx}9 times greater than bulk and is {approx}1/28 of the indium shear modulus, suggesting that the attained stresses are close to theoretical strength. Microcompression of hollow indium nanopillars showed evidence of brittle fracture. This may suggest that the failure mode for one of the most ductile metals can become brittle when the feature size is sufficiently small.

  15. First wall design of aluminium alloy R-tokamak

    International Nuclear Information System (INIS)

    A design study of a low-activation D-T tokamak Reacting Plasma Project In Nagoya has been finished. The study emphasizes the vacuum vessel and the bumper limiter. Our choice of materials (aluminium vacuum vessel, copper conductors, aluminium TF coil case and lead shield) results in a radiation level of about 1 x 10-3 times that of a TFTR type design, and 1 x 10-4 times that of JET type design, at 2 weeks after one D-T shot. Thick graphite tiles will be fixed directly on the aluminium vacuum vessel using aluminium spring washers and bolts. With this simplified structure of the bumper limiter, the inner surface temperature of the thick aluminium vacuum vessel will be less than 1200C which is required to reduce the overaging effect of the aluminium alloy. (orig.)

  16. What is the risk of aluminium as a neurotoxin?

    Science.gov (United States)

    Exley, Christopher

    2014-06-01

    Aluminium is neurotoxic. Its free ion, Al(3+) (aq), is highly biologically reactive and uniquely equipped to do damage to essential cellular (neuronal) biochemistry. This unequivocal fact must be the starting point in examining the risk posed by aluminium as a neurotoxin in humans. Aluminium is present in the human brain and it accumulates with age. The most recent research demonstrates that a significant proportion of individuals older than 70 years of age have a potentially pathological accumulation of aluminium somewhere in their brain. What are the symptoms of chronic aluminium intoxication in humans? What if neurodegenerative diseases such as Alzheimer's disease are the manifestation of the risk of aluminium as a neurotoxin? How might such an (outrageous) hypothesis be tested?

  17. Feet sunk in molten aluminium: The burn and its prevention.

    Science.gov (United States)

    Alonso-Peña, David; Arnáiz-García, María Elena; Valero-Gasalla, Javier Luis; Arnáiz-García, Ana María; Campillo-Campaña, Ramón; Alonso-Peña, Javier; González-Santos, Jose María; Fernández-Díaz, Alaska Leonor; Arnáiz, Javier

    2015-08-01

    Nowadays, despite improvements in safety rules and inspections in the metal industry, foundry workers are not free from burn accidents. Injuries caused by molten metals include burns secondary to molten iron, aluminium, zinc, copper, brass, bronze, manganese, lead and steel. Molten aluminium is one of the most common causative agents of burns (60%); however, only a few publications exist concerning injuries from molten aluminium. The main mechanisms of lesion from molten aluminium include direct contact of the molten metal with the skin or through safety apparel, or when the metal splash burns through the pants and rolls downward along the leg. Herein, we report three cases of deep dermal burns after 'soaking' the foot in liquid aluminium and its evolutive features. This paper aims to show our experience in the management of burns due to molten aluminium. We describe the current management principles and the key features of injury prevention.

  18. Toxicity of dissolved and precipitated aluminium to marine diatoms.

    Science.gov (United States)

    Gillmore, Megan L; Golding, Lisa A; Angel, Brad M; Adams, Merrin S; Jolley, Dianne F

    2016-05-01

    Localised aluminium contamination can lead to high concentrations in coastal waters, which have the potential for adverse effects on aquatic organisms. This research investigated the toxicity of 72-h exposures of aluminium to three marine diatoms (Ceratoneis closterium (formerly Nitzschia closterium), Minutocellus polymorphus and Phaeodactylum tricornutum) by measuring population growth rate inhibition and cell membrane damage (SYTOX Green) as endpoints. Toxicity was correlated to the time-averaged concentrations of different aluminium size-fractions, operationally defined as permeability were observed for any of the three diatoms suggesting that mechanisms of aluminium toxicity to diatoms do not involve compromising the plasma membrane. These results indicate that marine diatoms have a broad range in sensitivity to aluminium with toxic mechanisms related to both dissolved and precipitated aluminium. PMID:26921729

  19. Feet sunk in molten aluminium: The burn and its prevention.

    Science.gov (United States)

    Alonso-Peña, David; Arnáiz-García, María Elena; Valero-Gasalla, Javier Luis; Arnáiz-García, Ana María; Campillo-Campaña, Ramón; Alonso-Peña, Javier; González-Santos, Jose María; Fernández-Díaz, Alaska Leonor; Arnáiz, Javier

    2015-08-01

    Nowadays, despite improvements in safety rules and inspections in the metal industry, foundry workers are not free from burn accidents. Injuries caused by molten metals include burns secondary to molten iron, aluminium, zinc, copper, brass, bronze, manganese, lead and steel. Molten aluminium is one of the most common causative agents of burns (60%); however, only a few publications exist concerning injuries from molten aluminium. The main mechanisms of lesion from molten aluminium include direct contact of the molten metal with the skin or through safety apparel, or when the metal splash burns through the pants and rolls downward along the leg. Herein, we report three cases of deep dermal burns after 'soaking' the foot in liquid aluminium and its evolutive features. This paper aims to show our experience in the management of burns due to molten aluminium. We describe the current management principles and the key features of injury prevention. PMID:25687835

  20. Straggling of heavy ions in aluminium

    International Nuclear Information System (INIS)

    An effort has been made to determine the straggling in aluminium of 4He, 16O and 35Cl ions of different energies produced by the tandem Van de Graaff at Harwell. The technique consists of scattering the accelerated and collimated ions in a scattering chamber from a 0.100 mg/cm2 gold foil, allowing the scattered ions to pass through a two aperture collimator, using different aluminium foils over one of the apertures and stopping the two emergent beams in a good quality silicon surface barrier detector the output of which is connected to a 4096 channel analyser. The energy widths obtained in the case of helium ions are in fair agreement with both the Bloch and the recent Tschalar (1968) theory. The measured widths in the case of heavy ions are very large and can be explained only if account is taken of their charge distributions in foils. This study should be useful in ion implantation work. (author)

  1. China will Reduce Aluminium Export in 2005

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    <正>Starting from January 1, 2005, China eliminated the 8 per cent export tax rebate for aluminium, and further more, the exporters will have to pay 5 per cent export tax. This is beyond the expectations of the producers, for most of them thought only the 8 per cent export tax rebate would be eliminated and it was still too early to add the export tax.

  2. FSW characterization of 6082 aluminium alloys sheets

    OpenAIRE

    K. Mroczka; A. Pietras

    2009-01-01

    Purpose: The purpose of the investigations was to elaborate a set of FSW parameters for connecting 6082 aluminium alloy sheets allowing to produce welds of highest strength.Design/methodology/approach: The FSW was tried at different speeds and at additional cooling. The welds microstructure was studied using optical and scanning electron microscopes. The mechanical properties of produced connections are discussed regarding their tensile test and microhardness measurements.Findings: The FSW we...

  3. Methods of inoculation of pure aluminium structure

    Directory of Open Access Journals (Sweden)

    J. Szajnar

    2008-03-01

    Full Text Available Purpose: The main aim of investigations was the reduction of grain size and unification of structure for pure Al casting by introduction of small amount of inoculant (less than obligatory standart PN-EN 573-3, which concerning about aluminium purity, with electromagnetic field and variable casting parameters.Design/methodology/approach: To investigations it was used light microscopy and TEM. Surfaces of samples which were prepared for macro- and microstructure analysis were etched with use of solution of: 50g Cu, 400ml HCl, 300ml HNO3 and 300ml H2O. Thin foils for TEM investigations were electropolished with use of 20 ml HClO4 and 80ml CH3OH.Findings: The results of investigations and their analysis show possibility of effective inoculation of pure aluminium structure by use of some factors such as: different materials of the mould, influencing of stirring electromagnetic field into metal during solidification, inoculation by introducing AlTi5B1 inoculant into liquid aluminium and changing the pouring temperature.Research limitations/implications: I further research, authors of this paper are going to application of introduced method of inoculation in industrial tests.Practical implications: The work presents refinement of structure method which are particularly important in continuous and semi – continuous casting where products are used for plastic forming. Large columnar crystals zone result in forces extrusion rate reduction and during the ingot rolling delamination of external layers can occur. Thus, in some cases ingot skinning is needed, which rises the production costs.Originality/value: Contributes to research on size reduction in pure aluminium structure.

  4. Aluminium matrix composites fabricated by infiltration method

    OpenAIRE

    L.A. Dobrzański; M. Kremzer; A. J. Nowak; Nagel, A.

    2009-01-01

    Purpose: The aim of this work is to examine the structure and properties of metal matrix composites obtained by infiltration method of porous ceramic preforms by liquid aluminium alloy.Design/methodology/approach: Ceramic preforms were manufactured by the sintering method of ceramic powder. The preform material consists of powder Condea Al2O3 CL 2500, however, as the pore forming the carbon fibers Sigrafil C10 M250 UNS were used. Then ceramic preforms were infiltrated with liquid eutectic EN ...

  5. Softening Behaviour of Selected Commercially Pure Aluminium Model Alloys

    OpenAIRE

    Sande, Gunnar

    2012-01-01

    A characterization of the softening behaviour of four different commercially pure aluminium alloys has been carried out. The work is related to the MOREAL project (Modelling towards value-added recycling friendly aluminium alloys), where the main goal is to quantify the effect of the elements in recyclable aluminium alloys on microstructure and mechanical properties during thermo-mechanical processing. Typical elements are iron (Fe), silicon (Si) and manganese (Mn), and the alloys studied in ...

  6. Un-optimistic Prospects for the Westward Movement of Aluminium

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    <正>The westward movement of aluminium is essential for the industrial development.Up till now,the northwestern area has planned to construct more than 40 aluminium projects with a total production capacity of over 20 million tons.The future rate of progress of newly constructed projects are directly related to the supplies of the aluminium market,having critical guiding meaning for the trends of

  7. Friction factor of CP aluminium and aluminium–zinc alloys

    Indian Academy of Sciences (India)

    N Vidhya Sagar; K S Anand; A C Mithun; K Srinivasan

    2006-12-01

    Friction factor has been determined for CP aluminium and aluminium–zinc alloys using ring compression test at different temperatures from 303 K to 773 K. It is found that CP aluminium exhibits sticking whereas Al–Zn alloys do not exhibit sticking at elevated temperatures. Hot working of Al–Zn alloy is easier than that of CP aluminium at 773 K. As zinc content increases up to 10 wt% the friction factor decreases up to 0.02.

  8. Aluminium supplier selection for the automotive parts manufacturer

    OpenAIRE

    M. Cieśla

    2016-01-01

    This paper presents a methodology for selection of the optimal sources of supply, which is also known as the problem of supplier selection. Theoretical considerations are expanded with research related to aluminium supplier selection for a hypothetical manufacturer of aluminium parts for transportation equipment located in Poland. Evaluation of five suppliers of aluminium from Poland, Germany and Slovenia has been conducted using a weighted scoring method, a strengths and weaknesses method an...

  9. Corrosion of Metal-Matrix Composites with Aluminium Alloy Substrate

    Directory of Open Access Journals (Sweden)

    B. Bobic

    2010-03-01

    Full Text Available The corrosion behaviour of MMCs with aluminium alloy matrix was presented. The corrosion characteristics of boron-, graphite-, silicon carbide-, alumina- and mica- reinforced aluminium MMCs were reviewed. The reinforcing phase influence on MMCs corrosion rate as well as on various corrosion forms (galvanic, pitting, stress corrosion cracking, corrosion fatique, tribocorrosion was discussed. Some corrosion protection methods of aluminium based MMCs were described

  10. Tribological characteristics of coatings on aluminium and its alloys

    OpenAIRE

    Abdul-Mahdi, Fadhil S

    1987-01-01

    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. Hard anodising on aluminium and its alloys has been widely practised for many years in order to improve the resistance of the otherwise poor wear characteristics of aluminium. In recent years there has been an increasing interest in other treatments and coatings, on both aluminium and other base metals. The aim of this investigation is to explain the tribological performance and wear mechanis...

  11. Wearing tests on aluminium coated with diamond by triboadhesion

    Institute of Scientific and Technical Information of China (English)

    J.M.RodríguezLelis; B.D.Angulo; J.O.Colín; J.PorcayoCalderón

    2001-01-01

    In this work the results obtained from subjecting aluminium coated with diamond by tri-boadhesion to a wearing process with a plane rider. Here it is shown the ratio of the normal toshearing forces, called friction factor, as an indication of the resistance of the surface. It was foundthat the film of the aluminium coated with diamond resisted three times compared with the oxida-tion film of commercial aluminium, which for the purpose of this work was considered withoutcoating.

  12. Behaviour and design of aluminium alloy structural elements

    OpenAIRE

    Su, Meini; 蘇玫妮

    2014-01-01

    Aluminium alloys are nonlinear metallic materials with continuous stress-strain curves that are not well represented by the simplified elastic, perfectly plastic material model used in most existing design specifications. The aims of this study are to develop a more efficient design method for aluminium alloy structures by rationally exploiting strain hardening. The key components of this study include laboratory testing, numerical modelling and development of design guidance for aluminium al...

  13. Multiply-negatively charged aluminium clusters and fullerenes

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, Noelle

    2008-07-15

    Multiply negatively charged aluminium clusters and fullerenes were generated in a Penning trap using the 'electron-bath' technique. Aluminium monoanions were generated using a laser vaporisation source. After this, two-, three- and four-times negatively charged aluminium clusters were generated for the first time. This research marks the first observation of tetra-anionic metal clusters in the gas phase. Additionally, doubly-negatively charged fullerenes were generated. The smallest fullerene dianion observed contained 70 atoms. (orig.)

  14. Aluminium in the rail transportation market

    Energy Technology Data Exchange (ETDEWEB)

    Zehnder, J. [Alcan Alesa Engineering Ltd., Zurich (Switzerland). Alcan Mass Transportation Systems

    2002-07-01

    Rail-transportation is not, as one might expect, a homogeneous market but extremely fragmented and even with huge differences from continent to continent, i.e. in North America freight transport is dominating whereas in Europe passenger transport prevails. A first segmentation splits infrastructure from vehicles. In a second layer of segmentation we distinguish between light rail vehicles, heavy metros, regional trains, intercity trains, high speed trains with and without tilting, maglev trains, freight vehicles and locomotives. Finally, we find aluminium applications in wheels, suspension parts, brake equipment, traction equipment, body structure, hang on parts and interior trim. On the infrastructure side best use of aluminium is in the field of power supply. In order to have the best solution for each application, all forms of products such as castings, forgings, flat rolled products and extrusions are needed and the engineers are using a broad choice or different alloys for all the requirements such as structural strength, decorative aspect, electrical conductivity, wear resistance, weldability, corrosion resistance etc. Innovation cycles in rail transportation are very slow, mainly because the expected life of vehicles is over 30 years and so no fleet owner will run the risk of getting vehicles with non-proven components, i.e. where a safe life of over 30 years cannot be shown. In the following the most important aluminium applications are shown and discussed. (orig.)

  15. Plasmonic enhancement of photoluminescence from aluminium nitride

    Science.gov (United States)

    Flynn, Chris; Stewart, Matthew

    2016-03-01

    Aluminium nitride (AlN) films were grown on c-plane sapphire wafers by molecular beam epitaxy (MBE) under aluminium-rich conditions. The excess aluminium (Al) accumulated on the surface of the films as micro-scale droplets 1-10 μm in size, and as Al nanoparticles with diameters in the range 10-110 nm. Photoluminescence (PL) measurements were performed on the AlN samples using a 193 nm Excimer laser as the excitation source. Prior to PL measurements the wafers were cleaved in half. One half of each wafer was submitted to a 10 min treatment in H3PO4 heated to 70 °C to remove the excess Al from the film surface. The remaining half was left in the as-deposited condition. The mean intensities of the near-band-edge PL peaks of the as-deposited samples were 2.0-3.4 times higher compared to the samples subjected to the H3PO4 Al-removal treatment. This observation motivated calculations to determine the optimal Al surface nanosphere size for plasmonic enhancement of PL from AlN. The PL enhancement was found to peak for an Al nanosphere radius of 15 nm, which is within the range of the experimentally-observed Al nanoparticle sizes.

  16. Aluminium composite casting dispersion reinforced with iron-aluminium and silicon carbide phases

    Directory of Open Access Journals (Sweden)

    B. Formanek

    2010-10-01

    Full Text Available Aluminium matrix composite with dispersion-reinforced, made by similar to stircasting process was characterised. The mixture of powders was produced by the process of mechanical agglomeration of powdered FexAly and SiC with aluminium. The chemical composition ofagglomerates was selected in a way such as to obtain 25 wt.% reinforcement of the AlSi9Cu4 silumin matrix. Applying thermal analysis ATD, the alloy solidification process was determined, reading out the typical solidification parameters. The methods of light and scanning microscopy were used to reveal the structure of composite casting. Changes in chemical composition and phase composition of particles of the FeAl intermetallic phase in aluminium matrix were confirmed. The structure of silumin casting with matrix containing microregions of ceramic and intermetallic phases, typical of hybrid reinforcements, was obtained.

  17. Thermal formation of corundum from aluminium hydroxides prepared from various aluminium salts

    Indian Academy of Sciences (India)

    J Temuujin; Ts JADAMBAA; K J D Mackenzie; P Angerer; F Porte; F Riley

    2000-08-01

    Aluminium hydroxides have been precipitated from various aluminium salts and the differences in their thermal behaviour have been investigated. Pseudoboehmite derived from the nitrate, sulfate and chloride all form -Al2O3 at ∼ 400°C but the formation of -Al2O3 at 1200°C occurs more readily in the material derived from the sulfate. This contains a higher concentration of anionic impurities related to differences in the solubility of the original aluminium salts. The sulfate is retained in the gel to higher temperatures at which its eventual decomposition may lead to the formation of a reactive pore structure which facilitates the nucleation of -Al2O3.

  18. Synthesis of aluminium nanoparticles by arc evaporation of an aluminium cathode surface

    Indian Academy of Sciences (India)

    M Gazanfari; M Karimzadeh; S Ghorbani; M R Sadeghi; G Azizi; H Karimi; N Fattahi; Z Karimzadeh

    2014-06-01

    Aluminium nanoparticles (Al Nps) are synthesized using arc discharge method by applying direct current between aluminium electrodes in liquid environment without any use of vacuum equipment, heat exchangers, high temperatures furnaces and inert gases. After synthesis of Al Nps, in situ coating process on the nanoparticles was performed immediately. The effects of media on the yield and morphology of aluminium nanoparticles were investigated. Analysis result of the samples indicated that particle size was less than 30 nm, when 120 A/cm2 arc current was used. In addition, coating agent can affect arc velocity, arc stability, morphology and composition of the nanoparticles. Resultant nanoparticles were identified using X-ray powder diffraction (XRD), also their surface morphology was studied by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and finally the accuracy of coating was assessed with infrared (IR) spectroscopy.

  19. Investigation of the titanium-indium system

    Energy Technology Data Exchange (ETDEWEB)

    Gulay, L.D.; Schuster, J.C

    2003-10-06

    The phase diagram of the Ti-In system was determined using DTA, XRD and EDX analyses. The existence of the phases Ti{sub 2}In{sub 5} [Mn{sub 2}Hg{sub 5} type structure, space group P4/mbm, a=0.99995(3), c=0.29960(2) nm] and Ti{sub 3}In [Ni{sub 3}Sn type structure, space group P6{sub 3}/mmc, a=0.5978(1), c=0.4812(1) nm] was confirmed. The phase previously labeled Ti{sub 3}In{sub 2} was found to exist in a narrow homogeneity region near Ti{sub 56}In{sub 44}. Rietveld refinement of the XRD powder pattern yielded solutions compatible with a Cu{sub 3}Au-type or a BiIn-type crystal structure, but not with a CuAu-type crystal structure. Furthermore, at 38.5 at.% In, a new phase was observed having a {gamma}-brass related crystal structure [Ti{sub 8}In{sub 5}, space group P4-bar 3m, a=0.99578(6) nm]. The intermetallic phases were formed by a cascade of peritectic reactions ending in a eutectic at >99 at.% indium between Ti{sub 2}In{sub 5} and (In) at 0.4 K below the melting temperature of pure indium.

  20. Indium-111 platelet scintigraphy in carotid disease

    Energy Technology Data Exchange (ETDEWEB)

    Branchereau, A.; Bernard, P.J.; Ciosi, G.; Bazan, M.; de Laforte, C.; Elias, A.; Bouvier, J.L.

    1988-07-01

    Forty-five patients (35 men, 10 women) undergoing carotid surgery had Indium-111 platelet scintigraphy as part of their preoperative work-up. Imaging was performed within three hours after injection of the Indium-111. A second series of views was obtained 24 hours later and repeated at 24 hour intervals for two days. Of 54 scintigrams, 22 were positive and 32 negative. Positive results were defined as a twofold or more increase in local activity on a visualized carotid after 24 hours. The sensitivity of the method was 41%, intraoperatively, and the specificity, 100%. The low sensitivity places this method behind sonography and duplex-scanning for screening patients for surgery. We believe that indications for platelet scintigraphy are limited to: 1. Repeated transient ischemic attacks in the same territory with minimal lesions on arteriography and non-homogeneous plaque on duplex scan; 2. Symptomatic patients being treated medically as a possible argument for surgery; 3. Determining therapeutic policy for patients having experienced a transient ischemic attack with a coexisting intracardiac thrombus.

  1. Cold-impregnated aluminium. A new source of nickel exposure.

    Science.gov (United States)

    Lidén, C

    1994-07-01

    A new technique for finishing anodized aluminium was introduced during the 1980s--cold impregnation with nickel. Nickel is available on the surface of cold-impregnated aluminium, as shown by the dimethylglyoxime test. Chemical analysis with EDXA showed that nickel was in the form of NiSO4. A case of work-related allergic contact dermatitis in an engraver with nickel allergy is reported. It transpired that the patient was exposed to nickel in connection with aluminium. It is concluded that cold-impregnated aluminium is a new source of nickel exposure, probably previously unknown to dermatologists. PMID:7924288

  2. Effects of aluminium surface morphology and chemical modification on wettability

    Science.gov (United States)

    Rahimi, M.; Fojan, P.; Gurevich, L.; Afshari, A.

    2014-03-01

    Aluminium alloys are some of the predominant metals in industrial applications such as production of heat exchangers, heat pumps. They have high heat conductivity coupled with a low specific weight. In cold working conditions, there is a risk of frost formation on the surface of aluminium in the presence of water vapour, which can lead to the deterioration of equipment performance. This work addresses the methods of surface modification of aluminium and their effect of the underlying surface morphology and wettability, which are the important parameters for frost formation. Three groups of real-life aluminium surfaces of different morphology: unpolished aluminium, polished aluminium, and aluminium foil, were subjected to surface modification procedures which involved the formation of a layer of hydrophilic hyperbranched polyethyleneglycol via in situ polymerization, molecular vapour deposition of a monolayer of fluorinated silane, and a combination of those. The effect of these surface modification techniques on roughness and wettability of the aluminium surfaces was elucidated by ellipsometry, contact angle measurements and atomic force microscopy. We demonstrated that by employing different types of surface modifications the contact angle of water droplets on aluminium samples can be varied from 12° to more than 120°. A crossover from Cassie-Baxter to Wenzel regime upon changing the surface roughness was also observed.

  3. Friction stir welding (FSW of aluminium foam sandwich panels

    Directory of Open Access Journals (Sweden)

    M. Bušić

    2016-07-01

    Full Text Available The article focuses on the influence of welding speed and tool tilt angle upon the mechanical properties at the friction stir welding of aluminium foam sandwich panels. Double side welding was used for producing butt welds of aluminium sandwich panels applying insertion of extruded aluminium profile. Such insertion provided lower pressure of the tool upon the aluminium panels, providing also sufficient volume of the material required for the weldment formation. Ultimate tensile strength and flexural strength for three-point bending test have been determined for samples taken from the welded joints. Results have confirmed anticipated effects of independent variables.

  4. Aluminium anode for biogalvanic metal--oxygen -cells

    Energy Technology Data Exchange (ETDEWEB)

    Weidlich, E.

    1975-02-20

    The invention deals with an aluminium anode for biogalvanic metal--oxygen cells. The object of the invention is to improve further an aluminium anode for biogalvanic metal--oxygen cells. In particular, the lifetime is to be increased and the Faraday degree of efficiency is to be improved by suppressing an excessive hydrogen development. The anode is thus constructed so as to have a metal net on both sides with aluminium layers, and the surfaces of the aluminium layers not facing the metal net are lapped or sand-blasted and have an anodized layer on their boundary regions.

  5. Negative aluminium electrode for biogalvanic metal-oxygen cells

    Energy Technology Data Exchange (ETDEWEB)

    Weidlich, E.

    1977-03-24

    The invention deals with an aluminium anode for biogalvanic metal-oxygen cells. The object of the invention is to further improve an aluminium anode for biogalvanic metal-oxygen cells. In particular, the service life is to be increased and the Faraday degree of efficiency is to be improved, by suppressing an excessive hydrogen development. The anode is thus constructed so as to have a metal net on both sides with aluminium layers and the surfaces of the aluminium layers not facing the metal net are lapped or sand-blasted and have an eloxal layer on their boundary regions.

  6. Distribution of elastic strains appearing in gallium arsenide as a result of doping with isovalent impurities of phosphorus and indium

    Energy Technology Data Exchange (ETDEWEB)

    Pavlov, D. A. [Nizhni Novgorod Lobachevsky State University (Russian Federation); Bidus, N. V. [Nizhny Novgorod State University, Physicotechnical Research Institute (Russian Federation); Bobrov, A. I., E-mail: bobrov@phys.unn.ru [Nizhni Novgorod Lobachevsky State University (Russian Federation); Vikhrova, O. V. [Nizhny Novgorod State University, Physicotechnical Research Institute (Russian Federation); Volkova, E. I. [Nizhni Novgorod Lobachevsky State University (Russian Federation); Zvonkov, B. N. [Nizhny Novgorod State University, Physicotechnical Research Institute (Russian Federation); Malekhonova, N. V.; Sorokin, D. S. [Nizhni Novgorod Lobachevsky State University (Russian Federation)

    2015-01-15

    The distribution of elastic strains in a system consisting of a quantum-dot layer and a buried GaAs{sub x}P{sub 1−x} layer is studied using geometric phase analysis. A hypothesis is offered concerning the possibility of controlling the process of the formation of InAs quantum dots in a GaAs matrix using a local isovalent phosphorus impurity.

  7. Diagnostic imaging of musculoskeletal infection. Roentgenography; Gallium, indium-labeled white blood cell, gammaglobulin, bone scintigraphy; and MRI

    Energy Technology Data Exchange (ETDEWEB)

    Wegener, W.A.; Alavi, A. (Hospital of the University of Pennsylvania, Philadelphia (USA))

    1991-07-01

    A great deal of effort has been made to evaluate and define the role of various diagnostic imaging techniques in various clinical settings that complicate the diagnosis of osteomyelitis. Except possibly in neonates, bone scintigraphy remains generally recommended when there has been no previous osseous involvement. In other cases of chronic disease, previous fracture or trauma, prosthesis, and diabetic foot, In-WBC scintigraphy is generally accepted as an appropriate imaging technique. MRI will play an increasingly important role in diagnosing osteomyelitis and may prove to be an important adjunct in these cases. Research continues to improve our current diagnostic armamentarium. In-IgG appears to avoid practical deficiencies encountered with 67Ga and In-WBC; it remains to be seen what role this agent will play in routine clinical practice. All agents to date image inflammation, not infection, and most require delayed imaging sessions, usually at 24 hours. These shortcomings necessitate further research to develop new radiotracers that can provide useful images within several hours and that are specific for infection, perhaps ultimately delineating the particular microorganism involved.84 references.

  8. Reclamation of gallium, indium and rare-earth elements from photovoltaics, lightning and electronic waste : Reclaim project and outlook

    NARCIS (Netherlands)

    Kleef, M. van; Bisselink, R.; Ansems, T.; Kopacek, B.

    2014-01-01

    Modern technologies for green electronics like photovoltaic systems and solidstate lighting require increasing amounts of scarce metals. Global demand and price of these materials is expected to increase significantly the coming decades. If not controlled well some of these resources may be exhauste

  9. Surface reactivity and oxygen migration in amorphous indium-gallium-zinc oxide films annealed in humid atmosphere

    International Nuclear Information System (INIS)

    An isotope tracer study, i.e., 18O/16O exchange using 18O2 and H218O, was performed to determine how post-deposition annealing (PDA) affected surface reactivity and oxygen diffusivity of amorphous indium–gallium–zinc oxide (a-IGZO) films. The oxygen tracer diffusivity was very high in the bulk even at low temperatures, e.g., 200 °C, regardless of PDA and exchange conditions. In contrast, the isotope exchange rate, dominated by surface reactivity, was much lower for 18O2 than for H218O. PDA in a humid atmosphere at 400 °C further suppressed the reactivity of O2 at the a-IGZO film surface, which is attributable to –OH-terminated surface formation

  10. Thermal Characteristics of Amorphous Indium-Gallium-Zinc-Oxide and Graphite in Display Panel Based Thin Film Transistors.

    Science.gov (United States)

    Kim, Hak-Jun; Kim, Youn-Jea

    2015-11-01

    One of the important design factors in the smart electronic industry is proper heat treatment of the display panel. In order to improve the heat transfer performance of display panels, we analyzed a three-dimensional model of multi-stack layers of the thin film transistors (TFTs). In particular, we numerically investigated the thermal barrier effects of active layers having different material properties of a-IGZO (isotropy) and graphite (anisotropy). We calculated the temperature distribution on the display panel with each active layer, using the commercial code, COMSOL Multiphysics. We graphically depict comparative results of the thermal characteristics between a-IGZO and graphite with the stacked structure of the TFTs. PMID:26726627

  11. Development of a unique laboratory standard indium gallium arsenide detector for the 500 to 1700 micron spectral region, phase 2

    Science.gov (United States)

    Ban, Vladimir S.; Olsen, Gregory H.

    1990-01-01

    In the course of this work, 5 mm diameter InGaAs pin detectors were produced which met or exceeded all of the goals of the program. The best results achieved were: shunt resistance of over 300 K ohms; rise time of less than 300 ns; contact resistance of less than 20 ohms; quantum efficiency of over 50 percent in the 0.5 to 1.7 micron range; and devices were maintained and operated at 125 C without deterioration for over 100 hours. In order to achieve the goals of this program, several major technological advances were realized, among them: successful design, construction and operation of a hydride VPE reactor capable of growing epitaxial layers on 2 inch diameter InP substrates with a capacity of over 8 wafers per day; wafer processing was upgraded to handle 2 inch wafers; a double layer Si3N4/SiO2 antireflection coating which enhances response over the 0.5 to 1.7 micron range was developed; a method for anisotropic, precisely controlled CH4/H2 plasma etching for enhancement of response at short wavelengths was developed; and electronic and optical testing methods were developed to allow full characterization of detectors with size and spectral response characteristics. On the basis of the work and results achieved in this program, it is concluded that large size, high shunt resistance, high quantum efficiency InGaAs pin detectors are not only feasible but also manufacturable on industrial scale. This device spans a significant portion of visible and near infrared spectral range and it will allow a single detector to be used for the 0.5 to 1.7 micron spectral region, rather than the presently used silicon (for 0.5 to 1.1 microns) and germanium (0.8 to 1.7 microns).

  12. Epitaxial growth of III-V nitrides and phase separation and ordering in indium gallium nitride alloys

    Science.gov (United States)

    Doppalapudi, Dharanipal

    The family of III-V nitrides are wide band-gap semiconductors with a broad range of opto-electronic applications in LEDs, laser diodes, UV detectors as well as high temperature/high frequency devices. Due to the lack of good quality native substrates, GaN is grown on foreign substrates that have a lattice and thermal mismatch with GaN. This results in a material with a high density of defects, which in turn adversely affects the opto-electronic properties of the epilayer. In this study, GaN films were epitaxially grown on various substrates (C-plane sapphire, A-plane sapphire, SiC and ZnO) by molecular beam epitaxy. Additionally, GaN homoepitaxy onto laterally overgrown thick GaN substrates was investigated. It was demonstrated that the polarity of the GaN film plays a major role in determining the properties of the films. The growth parameters were optimized to eliminate inversion domain boundaries, which result in domains of opposite polarity in the GaN lattice. For growth on A-plane sapphire, it was found that substrate nitridation and low temperature buffer deposition are critical in order to obtain good epitaxial growth, in spite of the relatively small mismatch between the film and substrate. A crystallographic model was developed to explain this observation. By optimizing growth parameters, GaN films with excellent structural, transport, optical and device properties were grown. The second part of this research involves growth of ternary alloys and superlattice structures, which are essential in the fabrication of many devices. It was found that the InN-GaN pseudo-binary system is not homogeneous over the entire composition range. Due to the mismatch between the tetrahedral radii of GaN and InN, InGaN alloys exhibited phase separation and long-range atomic ordering. Investigations of InxGa1-xN films grown over a wide range of compositions by XRD and TEM showed that the predominant strain relieving mechanism was phase separation in films with x > 0.2, and ordering in films with x < 0.2. This spontaneous segregation of InGaN to form phase separated and ordered regions could justify the high luminescence efficiencies observed in this material in spite of its inherent high defect density. The degree of ordering in these alloys was found to increase with growth rate.

  13. Substrate engineering for defect reduction and microstructure control in the growth of indium arsenide on (100) gallium arsenide

    Science.gov (United States)

    Ganesan, Suryanarayanan

    The development of devices based on InAs, GaSb, and AlSb, semiconductors that possess narrow band-gaps and 0.61 nm lattice parameters, has been limited by the defects that ensue in epitaxial films that typically are grown on commercial semi-insulating, but 7% lattice-mismatched, GaAs substrates. The studies described in this dissertation investigate the application of a lateral epitaxial overgrowth technique for defect reduction and microstructure control to the InAs/GaAs heteroepitaxial system by exploring the development of microstructure at various stages of island and film growth in conventional and lateral overgrowth epitaxy (that is, on unpatterned and mask-patterned substrates, respectively). For a range of growth conditions, InAs films on unpatterned (100) GaAs substrates exhibit not only the threading dislocations characteristic of largely mismatched epitaxial films, but also systematic tilting within micron-scale InAs domains. Alteration of the pattern and magnitude of the tilt achieved by varying the growth conditions and/or introducing mask-patterned substrates suggest that not only chemical and kinetic, but also physical constraints can direct microstructural evolution during growth. Backscattered electron Kikuchi pattern-based orientation imaging was used to investigate the origin of the improved epitaxial alignment that is realized when InAs films were grown on mask-patterned (100) GaAs substrates. The island size at coalescence was shown to be critical in determining whether a single or two-fold, four-fold or six-fold epitaxial orientation relationship(s) is (are) present in the film. The evolution of tilt with increasing island size is attributed to the particulars of the misfit dislocation network that forms, which appears to evolve in this epitaxial system as the island grows, in accordance with a model proposed by Spencer and Tersoff [1,2]. Sub-micron (˜0.5 mum or less) island sizes at coalescence appear to lead to a single orientation aligned with the GaAs. This work shows that spatial constraints imposed at the early stages of growth, in this case through use of a mask-patterned substrate, can be used to promote coalescence at small island size as an alternative or parallel approach to setting growth conditions (temperature, precursor stoichiometry, etc.) in order to control the defect nucleation and microstructure. References. [1]. B.J. Spencer, and J. Tersoff, Appl. Phys. Lett. 77 (1997) 2533. [2]. B.J. Spencer, and J. Tersoff, Phys. Rev. B63 (2001) 205424.

  14. Dialkylaluminium-, -gallium-, and -indium-based poly-Lewis acids with a 1,8-diethynylanthracene backbone.

    Science.gov (United States)

    Chmiel, Jasmin; Neumann, Beate; Stammler, Hans-Georg; Mitzel, Norbert W

    2010-10-18

    Potential host systems based on a rigid 1,8-diethynylanthracendiyl backbone were synthesised by treatment of 1,8-diethynylanthracene with the Group 13 trialkyls AlMe(3), GaMe(3), InMe(3), AlEt(3) and GaEt(3). The resulting products were characterised by IR and multinuclear NMR spectroscopy, elemental analyses and determination of their crystal structures by X-ray diffraction. The compounds are dimeric in the solid state and comprise two M(2)C(2) heterocycles. Depending on the steric demand of the alkyl substituents at the metal atom, different types of binding modes were observed, which can be classified to lie between the ideals of side-on coordination with almost linear primary M-C≡C units and the 3c-2e coordination with symmetrically bridging alkynyl units in M-C-M bonds. As a solution in THF the dimers are broken into monomers and some are found to undergo ligand scrambling reactions. PMID:20827789

  15. Electrical dependence on the chemical composition of the gate dielectric in indium gallium zinc oxide thin-film transistors

    Science.gov (United States)

    Tari, Alireza; Lee, Czang-Ho; Wong, William S.

    2015-07-01

    Bottom-gate thin-film transistors were fabricated by depositing a 50 nm InGaZnO (IGZO) channel layer at 150 °C on three separate gate dielectric films: (1) thermal SiO2, (2) plasma-enhanced chemical-vapor deposition (PECVD) SiNx, and (3) a PECVD SiOx/SiNx dual-dielectric. X-ray photoelectron and photoluminescence spectroscopy showed the Vo concentration was dependent on the hydrogen concentration of the underlying dielectric film. IGZO films on SiNx (high Vo) and SiO2 (low Vo) had the highest and lowest conductivity, respectively. A PECVD SiOx/SiNx dual-dielectric layer was effective in suppressing hydrogen diffusion from the nitride layer into the IGZO and resulted in higher resistivity films.

  16. Densification effects on solution-processed indium-gallium-zinc-oxide films and their thin-film transistors

    Energy Technology Data Exchange (ETDEWEB)

    Rim, You Seung; Kim, Hyun Jae [School of Electrical and Electronic Engineering, Yonsei University, Seoul (Korea, Republic of)

    2014-09-15

    We report the effects of high-pressure annealing (HPA) on solution-processed InGaZnO (IGZO) thin-film transistors (TFTs). HPA increased the density of IGZO films. In particular, annealing in O{sub 2} at 1.0 MPa and 350 C resulted in a high-density and low-porosity IGZO film, as characterized using X-ray reflectivity (XRR) and ellipsometry measurements. This was attributed to the oxidative and compressive effects on the oxygen-deficient solution-processed IGZO film. TFTs annealed in O{sub 2} at 1.0 MPa and 350 C exhibited an increase in the field-effect mobility by a factor of approximately five compared with TFTs annealed in air at 0.1 MPa and 350 C. Furthermore, improvements in reliability under negative and positive bias stresses were also observed following HPA. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. Electrical dependence on the chemical composition of the gate dielectric in indium gallium zinc oxide thin-film transistors

    Energy Technology Data Exchange (ETDEWEB)

    Tari, Alireza, E-mail: atari@uwaterloo.ca; Lee, Czang-Ho; Wong, William S. [Department of Electrical and Computer Engineering, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1 (Canada)

    2015-07-13

    Bottom-gate thin-film transistors were fabricated by depositing a 50 nm InGaZnO (IGZO) channel layer at 150 °C on three separate gate dielectric films: (1) thermal SiO{sub 2}, (2) plasma-enhanced chemical-vapor deposition (PECVD) SiN{sub x}, and (3) a PECVD SiO{sub x}/SiN{sub x} dual-dielectric. X-ray photoelectron and photoluminescence spectroscopy showed the V{sub o} concentration was dependent on the hydrogen concentration of the underlying dielectric film. IGZO films on SiN{sub x} (high V{sub o}) and SiO{sub 2} (low V{sub o}) had the highest and lowest conductivity, respectively. A PECVD SiO{sub x}/SiN{sub x} dual-dielectric layer was effective in suppressing hydrogen diffusion from the nitride layer into the IGZO and resulted in higher resistivity films.

  18. Robust and stretchable indium gallium zinc oxide-based electronic textiles formed by cilia-assisted transfer printing

    Science.gov (United States)

    Yoon, Jongwon; Jeong, Yunkyung; Kim, Heeje; Yoo, Seonggwang; Jung, Hoon Sun; Kim, Yonghun; Hwang, Youngkyu; Hyun, Yujun; Hong, Woong-Ki; Lee, Byoung Hun; Choa, Sung-Hoon; Ko, Heung Cho

    2016-06-01

    Electronic textile (e-textile) allows for high-end wearable electronic devices that provide easy access for carrying, handling and using. However, the related technology does not seem to be mature because the woven fabric hampers not only the device fabrication process directly on the complex surface but also the transfer printing of ultrathin planar electronic devices. Here we report an indirect method that enables conformal wrapping of surface with arbitrary yet complex shapes. Artificial cilia are introduced in the periphery of electronic devices as adhesive elements. The cilia also play an important role in confining a small amount of glue and damping mechanical stress to maintain robust electronic performance under mechanical deformation. The example of electronic applications depicts the feasibility of cilia for `stick-&-play' systems, which provide electronic functions by transfer printing on unconventional complex surfaces.

  19. Role of Gallium and labeled leukocyte scintigraphy in AIDS patient

    International Nuclear Information System (INIS)

    Because AIDS patients frequently present with minimal symptomatology, radionuclide imaging with its ability to survey the entire body, is especially valuable. Gallium-67 citrate, the most commonly performed radionuclide study for localizing infection in these patients, is most useful for detecting opportunistic infections, especially in the thorax. A negative gallium scan, particularly when the chest X-ray is unremarkable, rules strongly against pulmonary disease. A negative gallium scan in a patient with an abnormal chest X-ray and Kaposi's sarcoma, suggests that the patient's respiratory distress is related to the neoplasm. Diffuse pulmonary parenchymal uptake of gallium in the HIV (+) patient is most often associated with PCP. While there are other causes of diffuse pulmonary uptake, the more intense or heterogeneous the uptake, the more likely the patient is to have PCP. Focal pulmonary uptake is usually associated with bacterial pneumonia although PCP may occasionally present in this fashion. Lymph node uptake of gallium is usually associated with Mycob acterium avium complex, tuberculosis, or Iymphoma. When corresponding abnormalities are present on thallium scintigraphy lymphoma is likely. Gallium positive, thallium negative, studies suggest mycobacterial disease. Labeled leukocyte imaging is not useful for detecting opportunistic infections probably because of the inflammatory response incited by these organisms. Leukocyte imaging is, however, more sensitive for detecting bacterial pneumonia. In the abdomen, gallium imaging is most useful for identifying lymphadenopathy, while labeled leukocyte imaging is superior for detecting AlDS-associated colitides. In summary, radionuclide studies are valuable diagnostic modalities in AIDS. Their success can be maximized by tailoring the study to the individual's needs

  20. A study on the recycling of aluminium alloy 7075 scrap

    Energy Technology Data Exchange (ETDEWEB)

    Oezer, Goekhan [Yildiz Technical Univ., Yildiz (TR). Balkan Centre of Advanced Casting Technologies (BACAT); Marsoglu, Muezeyyen [Yildiz Technical Univ., Yildiz (Turkey). Dept. for Metal and Materials Science Engineering; Burgucu, Sarp

    2012-07-01

    Aluminium and its alloys have recently become an important metal whose area and amount of usage increase more and more, due to their mechanical properties, recycling ability, and penetrability. If it is considered that the bauxite, which is the raw material of aluminium is rare on earth, and also the area and amount of aluminium usage increases over time, the importance of aluminium recycling goes up. aluminium recycling has become crucial by means of both, the potential of the scrap's dependant increase on usage and the primary aluminium production, as it is providing energy and cost savings. 7xxx grades of scrap are collected with other scrap of aluminium alloys in one turn and recycled all together. As the regain of these alloys is not done by isolation of the various grades, the finally recycled ingots result in lower grades. High value aluminium scrap is regrettably not recovered, as it was anticipated. This study is dealing with 7075 aluminium alloys originated from discharged blow molding tools and the rest piece cuttings of blocks and plates. The material has been subjected to an induction furnace, and has been remelted into small ingots and hardened according to 7075 aluminium alloy parameters (hardening aluminium tooling). [German] Aluminium und seine Legierungen sind in den letzten Jahren aufgrund ihrer mechanischen Eigenschaften, ihrer Recyclingfaehigkeit und ihrer Durchlaessigkeit immer bedeutendere metallische Werkstoffe geworden. Unter Beruecksichtigung, dass Bauxit als Rohmaterial selten auf der Erde vorkommt und der Verbrauch mit der Zeit steigt, waechst die Bedeutung des Recyclings von Aluminium. Aluminiumrecycling, zumal es Energieund Kosteneinsparungen ermoeglicht, ist sowohl fuer die schrottabhaengigen Verwendungspotentiale und die PrimaerAluminiumproduktion gleichermassen bedeutend geworden. Die 7xxxx Schrottlegierungen werden in einem Arbeitsgang mit dem Schrott aus anderen Aluminiumlegierungen gesammelt und recycled. Da die

  1. Effects of aluminium surface morphology and chemical modification on wettability

    Energy Technology Data Exchange (ETDEWEB)

    Rahimi, M., E-mail: mar@sbi.aau.dk [Department of Energy and Environment, Danish Building Research Institute, Aalborg University, A.C. Meyers Vænge 15, 2450 København SV (Denmark); Fojan, P.; Gurevich, L. [Department of Physics and Nanotechnology, Aalborg University, Skjernvej 4, DK-9220 Aalborg East (Denmark); Afshari, A. [Department of Energy and Environment, Danish Building Research Institute, Aalborg University, A.C. Meyers Vænge 15, 2450 København SV (Denmark)

    2014-03-01

    Highlights: • Successful surface modification procedures on aluminium samples were performed involving formation of the layer of hydrophilic hyperbranched polyethyleneglycol (PEG) via in situ polymerization, molecular vapour deposition of a monolayer of fluorinated silane, and a combination of those. • The groups of surfaces with hydrophobic behavior were found to follow the Wenzel model. • A transition from Cassie–Baxter's to Wenzel's regime was observed due to changing of the surface roughness upon mechanical polishing in aluminium samples. - Abstract: Aluminium alloys are some of the predominant metals in industrial applications such as production of heat exchangers, heat pumps. They have high heat conductivity coupled with a low specific weight. In cold working conditions, there is a risk of frost formation on the surface of aluminium in the presence of water vapour, which can lead to the deterioration of equipment performance. This work addresses the methods of surface modification of aluminium and their effect of the underlying surface morphology and wettability, which are the important parameters for frost formation. Three groups of real-life aluminium surfaces of different morphology: unpolished aluminium, polished aluminium, and aluminium foil, were subjected to surface modification procedures which involved the formation of a layer of hydrophilic hyperbranched polyethyleneglycol via in situ polymerization, molecular vapour deposition of a monolayer of fluorinated silane, and a combination of those. The effect of these surface modification techniques on roughness and wettability of the aluminium surfaces was elucidated by ellipsometry, contact angle measurements and atomic force microscopy. We demonstrated that by employing different types of surface modifications the contact angle of water droplets on aluminium samples can be varied from 12° to more than 120°. A crossover from Cassie–Baxter to Wenzel regime upon changing the surface

  2. There is (still too much aluminium in infant formulas

    Directory of Open Access Journals (Sweden)

    Burrell Shelle-Ann M

    2010-08-01

    Full Text Available Abstract Background Infant formulas are sophisticated milk-based feeds for infants which are used as a substitute for breast milk. Historically they are known to be contaminated by aluminium and in the past this has raised health concerns for exposed infants. We have measured the aluminium content of a number of widely used infant formulas to determine if their contamination by aluminium and consequent issues of child health persists. Methods Samples of ready-made milks and powders used to make milks were prepared by microwave digestion of acid/peroxide mixtures and their aluminium content determined by THGA. Results The concentration of aluminium in ready-made milks varied from ca 176 to 700 μg/L. The latter concentration was for a milk for preterm infants. The aluminium content of powders used to make milks varied from ca 2.4 to 4.3 μg/g. The latter content was for a soya-based formula and equated to a ready-to-drink milk concentration of 629 μg/L. Using the manufacturer's own guidelines of formula consumption the average daily ingestion of aluminium from infant formulas for a child of 6 months varied from ca 200 to 600 μg of aluminium. Generally ingestion was higher from powdered as compared to ready-made formulas. Conclusions The aluminium content of a range of well known brands of infant formulas remains high and particularly so for a product designed for preterm infants and a soya-based product designed for infants with cow's milk intolerances and allergies. Recent research demonstrating the vulnerability of infants to early exposure to aluminium serves to highlight an urgent need to reduce the aluminium content of infant formulas to as low a level as is practically possible.

  3. Electrolytic deposition of aluminium-magnesium-alloys from electrolytes containing organo-aluminium complexes; Elektrolytische Abscheidung von Aluminium-Magnesium-Legierungen aus aluminiumorganischen Komplexelektrolyten

    Energy Technology Data Exchange (ETDEWEB)

    Lehmkuhl, H.; Mehler, K.; Bongard, H.; Tesche, B. [Max-Planck-Institut fuer Kohlenforschung, Muelheim an der Ruhr (Germany); Reinhold, B. [Audi AG, Ingolstadt (Germany). Technische Entwicklung

    2000-10-01

    The galvanic deposition of pure aluminium from fluoride-containing electrolytes has been developed further and for the first time aluminium and magnesium have been deposited from a toluene-solution of a halide-free organo-aluminium complex electrolyte. The rate of incorporation of magnesium can be controlled over a wide range by either adjusting the composition of the aluminium-magnesium anode or by using separate aluminium or magnesium anodic circuits. The current efficiency for both anode and cathode approaches 100%. The resulting coating is optically attractive and, depending upon the magnesium-content or the cathodic current density, can be formed as a dull or polished surface. Investigations using an electron microscope show that the surface, in contrast to that of pure aluminium, consists of spherical particles. The aluminium-magnesium coating provides excellent protection against the corrosion of magnesium components. Electrochemical investigations using, for example 25% by weight magnesium incorporation, indicate a pronounced passivity interval compared to the alloy AZ91hp. In contrast to galvanic zinc-plated and silicate-sealed examples, cyclic corrosion tests on screws simulating 10 years of exposure, show no corrosion. (orig.)

  4. Self-consistent method for quantifying indium content from X-ray spectra of thick compound semiconductor specimens in a transmission electron microscope.

    Science.gov (United States)

    Walther, T; Wang, X

    2016-05-01

    Based on Monte Carlo simulations of X-ray generation by fast electrons we calculate curves of effective sensitivity factors for analytical transmission electron microscopy based energy-dispersive X-ray spectroscopy including absorption and fluorescence effects, as a function of Ga K/L ratio for different indium and gallium containing compound semiconductors. For the case of InGaN alloy thin films we show that experimental spectra can thus be quantified without the need to measure specimen thickness or density, yielding self-consistent values for quantification with Ga K and Ga L lines. The effect of uncertainties in the detector efficiency are also shown to be reduced. PMID:26258768

  5. Indium doped niobium phosphates as intermediate temperature proton conductors

    DEFF Research Database (Denmark)

    Huang, Yunjie; Li, Qingfeng; Anfimova, Tatiana;

    2013-01-01

    Indium doped niobium phosphates were prepared from precursors of trivalent indium oxide, pentavalent niobium oxide and phosphoric acid. The obtained materials were characterized by X-ray diffraction, impedance spectroscopy, FT-IR spectroscopy and scanning electron microscopy. It was found...... that the indium doping promoted formation of the cubic Nb2P4O15 phase instead of the monoclinic Nb5P7O30 phase in the pristine niobium phosphates and enhanced the preservation of OH functional groups in the phosphates. The preserved OH functionalities in the phosphates after the heat treatment at 650 °C...

  6. Effect of indium concentration on luminescence and electrical properties of indium doped ZnO nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Sin Yee [Department of Materials Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan, ROC (China); Brahma, Sanjaya [Center for Micro/Nano Science and Technology, National Cheng Kung University, Tainan 701, Taiwan, ROC (China); Liu, Chuan-Pu [Department of Materials Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan, ROC (China); Wang, Ruey-Chi [Department of Chemical and Materials Engineering, National University of Kaohsiung, Kaohsiung 81148, Taiwan, ROC (China); Huang, Jow-Lay, E-mail: JLH888@mail.ncku.edu.tw [Department of Materials Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan, ROC (China); Department of Chemical and Materials Engineering, National University of Kaohsiung, Kaohsiung 81148, Taiwan, ROC (China); Research Center for Energy Technology and Strategy, National Cheng Kung University, Tainan 701, Taiwan, ROC (China)

    2013-12-31

    In this work, indium (In) doped ZnO nanowires are grown on a Si substrate by chemical vapor deposition (CVD), at a relatively low temperature of 550 °C. The effects of In concentration on the morphology, microstructure, luminescence and electrical properties of ZnO nanowires are investigated. The diameters and lengths of these nanowires are in the ranges of 70–311 nm and 10–15 μm, respectively. These nanowires are single crystals growing in the [0001] direction. The maximum solubility of In in ZnO is estimated to be 3.47 at.%. Photoluminescence (PL) spectra reveal a red shift in the ultraviolet emission and intensity enhancement in the green emission with increasing indium doping concentration. Besides, carrier concentration, mobility and resistivity of the nanowires with different doping concentrations are determined based on single-nanowire field effect transistors (FET). - Highlights: • Indium (In) doped ZnO nanowires were grown by chemical vapor deposition at 550 °C. • In doping leads to an increase in the intensity of visible light emission. • Resistivity of the ZnO nanowire is lowered at high (3.47 at.%) In doping. • In doped ZnO nanowire field effect transistor (FET) was fabricated. • Mobility and carrier concentration were determined.

  7. Hydrogen Production via Steam Reforming of Ethyl Alcohol over Palladium/Indium Oxide Catalyst

    OpenAIRE

    Tetsuo Umegaki; Yusuke Yamada; Atsushi Ueda; Nobuhiro Kuriyama; Qiang Xu

    2009-01-01

    We report the synergetic effect between palladium and indium oxide on hydrogen production in the steam reforming reaction of ethyl alcohol. The palladium/indium oxide catalyst shows higher hydrogen production rate than indium oxide and palladium. Palladium/indium oxide affords ketonization of ethyl alcohol with negligible by-product carbon monoxide, while indium oxide mainly affords dehydration of ethyl alcohol, and palladium affords decomposition of ethyl alcohol with large amount of by-prod...

  8. Gas heat treatment plants for the aluminium industry; Gasbeheizte Waermebehandlungsanlagen fuer die Aluminium-Industrie

    Energy Technology Data Exchange (ETDEWEB)

    Olberts, P.; Hanus, A. [LOI Thermprocess GmbH, Essen (Germany)

    2004-09-01

    LOI Thermoprocess has developed new, flexible, innovative furnace designs for heat treatment of aluminium in general (car industry) and particularly for cylinder heads, engine units, chassis components, textured components, wheels, rolled sheet and extrusions. The furnaces are heated by means of radiant tubes (recuperators) and by the more usual open gas heating system (flue gas recirculation). (orig.)

  9. The aluminium body has been promoted in Canada; La carrosserie aluminium promue au Canada

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2004-02-01

    The aluminium vehicles technology is a technology which allows, with an equivalent structure, to decrease the weight of a car of 40%. Presented by the Alcan firm, this technology is one of the technologies of the year 2003. The Alcan firm has, besides, received the 2003 technology price awarded by the magazine Industry Week. (O.M.)

  10. Indium antimonide based HEMT for RF applications

    Institute of Scientific and Technical Information of China (English)

    T.D.Subash; T.Gnanasekaran

    2014-01-01

    We report on an indium antimonide high electron mobility transistor with record cut-off frequency characteristics.For high frequency response it is important to minimize parasitic resistance and capacitance to improve short-channel effects.For analog applications adequate pinch-off behavior is demonstrated.For proper device scaling we need high electron mobility and high electron density.Toward this end,the device design features and simulation are carried out by the Synopsys TCAD tool.A 30 nm InSb HEMT exhibits an excellent cut-off frequency of 586 GHz.To the knowledge of the authors,the obtained cut-off frequency is the highest ever reported in any FET on any material system.

  11. DD neutron yield diagnosis by indium activation

    International Nuclear Information System (INIS)

    The measurement of DD neutron yield by activation is presented. This method is based on the inelastic scattering reaction of 115In with DD neutron, and the activated γ spectrum is counted by HPGe detector. The relation between the counts of detected y rays and the neutron yield is analyzed. The optimal thickness of sample is given by Monte Carlo simulation, which is 1 cm. The entire counting system has been calibrated on the K-400 accelerator. The result shows that the DD neutron measurement by indium activation can be used in the ICF experiment when the neutron yield is above 2 × 109. The total error of the system is below 10% in this condition. The total error will reduce when the neutron yield is larger. (authors)

  12. Combined Corrosion and Wear of Aluminium Alloy 7075-T6

    NARCIS (Netherlands)

    Liu, Y.; Mol, J.M.C.; Janssen, G.C.A.M.

    2016-01-01

    The aluminium alloy 7075-T6 is widely used in engineering. In some applications, like slurry transport, corrosion and abrasion occur simultaneously, resulting in early material failure. In the present work, we investigated the combined effect of corrosion and wear on the aluminium alloy 7075-T6. We

  13. Aluminium removal from water after defluoridation with the electrocoagulation process.

    Science.gov (United States)

    Sinha, Richa; Mathur, Sanjay; Brighu, Urmila

    2015-01-01

    Fluoride is the most electronegative element and has a strong affinity for aluminium. Owing to this fact, most of the techniques used for fluoride removal utilized aluminium compounds, which results in high concentrations of aluminium in treated water. In the present paper, a new approach is presented to meet the WHO guideline for residual aluminium concentration as 0.2 mg/L. In the present work, the electrocoagulation (EC) process was used for fluoride removal. It was found that aluminium content in water increases with an increase in the energy input. Therefore, experiments were optimized for a minimum energy input to achieve the target value (0.7 mg/L) of fluoride in resultant water. These optimized sets were used for further investigations of aluminium control. The experimental investigations revealed that use of bentonite clay as coagulant in clariflocculation brings down the aluminium concentration of water below the WHO guideline. Bentonite dose of 2 g/L was found to be the best for efficient removal of aluminium.

  14. New Policies to Control the Aluminium Industry Expansion

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    <正>Information from China Nonferrous Metals Industry Association (CNIA) shows that new government policies on China’s aluminium industry will be released soon in order to control the rapid expansion of the aluminium industry which consumes large amount of power resources. Based on the new policies, investors of

  15. Chalco Calls for End of More Control Measures on Aluminium

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    <正> To control the investment rush in electrolyticaluminium in recent years and ensure thehealthy development of China’s aluminium in-dustry, the State Council recently released aseries of adjustment policies and control meas-ures,which effectively prevented theinvestment rush and limited the aluminium out-put growth.

  16. Haemodialysis related osteomalacia: a staining method to demonstrate aluminium

    OpenAIRE

    Buchanan, Malcolm RC; Ihle, Benno U; Dunn, Cheryl M

    1981-01-01

    A slight modification in tissue processing and staining technique enables a previously described method for staining aluminium to be used to demonstrate aluminium in osteomalacia associated with haemodialysis. The stain appears to be accurate in diagnosing this condition and may assist in establishing the diagnosis before severe osteomalacia develops.

  17. Developments in finite element simulations of aluminium extrusion

    NARCIS (Netherlands)

    Lof, Joeri

    2000-01-01

    Aluminium extrusion is a forming process used to produce profiles. A large variety of profiles can be made by pressing a billet of hot aluminium through a hole that closely resembles the required cross-section of the profie. At the present time, design of extrusion dies and operation in extrusion co

  18. Spark counting technique with an aluminium oxide film

    International Nuclear Information System (INIS)

    Automatic spark counting of etch-pits on a polycarbonate film produced by nuclear fission fragments is now used for neutron monitoring in several countries. A method was developed using an aluminium oxide film instead of a polycarbonate as the neutron detector. Aluminium oxide films were prepared as follows: A cleaned aluminium plate as an anode and a nickel plate as a cathode were immersed in dilute sulfuric acid solution and electric current flowed between the electrodes at 12degC for 10-30 minutes. Electric current density was about 10 mA/cm2. The aluminium plate was then kept in boiling water for 10-30 minutes for sealing. The thickness of the aluminium oxide layer formed was about 1μm. The aluminium plate attached to a plate of suitable fissionable material, such as uranium or thorium, was irradiated with neutrons and set in a usual spark counter for fission track counting. One electrode was the aluminium plate and the other was an aluminized polyester sheet. Sparked pulses were counted with a usual scaler. The advantage of using spark counting with an aluminium oxide film for neutron monitoring is rapid measurement of neutron exposure, since chemical etching which is indispensable for spark counting with a polycarbonate detector film, is not needed. (H.K.)

  19. CAD implementation of design rules for aluminium extrusion dies

    NARCIS (Netherlands)

    Ouwerkerk, van Gijs

    2009-01-01

    Aluminium extrusion is an industrial forming process that is used to produce long profiles of a constant cross-section. This cross-section is shaped by the opening in a steel tool known as the die. The understanding of the mechanics of the aluminium extrusion process is still limited. The flow of al

  20. Enhanced corrosion protection by microstructural control of aluminium brazing sheet

    NARCIS (Netherlands)

    Norouzi Afshar, F.

    2013-01-01

    Aluminium brazing sheet is a sandwich material made out of two aluminium alloys (AA4xxx/AA3xxx) and is widely used in automotive heat exchangers. One of the main performance criteria for heat exchanger units is the lifetime of the product. The lifetime of the heat exchanger units is determined by th

  1. Investigation on gallium ions impacting monolayer graphene

    Directory of Open Access Journals (Sweden)

    Xin Wu

    2015-06-01

    Full Text Available In this paper, the physical phenomena of gallium (Ga+ ion impacting monolayer graphene in the nanosculpting process are investigated experimentally, and the mechanisms are explained by using Monte Carlo (MC and molecular dynamics (MD simulations. Firstly, the MC method is employed to clarify the phenomena happened to the monolayer graphene target under Ga+ ion irradiation. It is found that substrate has strong influence on the damage mode of graphene. The mean sputtering yield of graphene under 30 keV Ga+ ion irradiation is 1.77 and the least ion dose to completely remove carbon atoms in graphene is 21.6 ion/nm2. Afterwards, the focused ion beam over 21.6 ion/nm2 is used for the irradiation on a monolayer graphene supported by SiO2 experimentally, resulting in the nanostructures, i.e., nanodot and nanowire array on the graphene. The performances of the nanostructures are characterized by atomic force microscopy and Raman spectrum. A plasma plume shielding model is put forward to explain the nanosculpting results of graphene under different irradiation parameters. In addition, two damage mechanisms are found existing in the fabrication process of the nanostructures by using empirical MD simulations. The results can help us open the possibilities for better control of nanocarbon devices.

  2. Gallium-based avalanche photodiode optical crosstalk

    Science.gov (United States)

    Blazej, Josef; Prochazka, Ivan; Hamal, Karel; Sopko, Bruno; Chren, Dominik

    2006-11-01

    Solid-state single photon detectors based on avalanche photodiode are getting more attention in various areas of applied physics: optical sensors, quantum key distribution, optical ranging and Lidar, time-resolved spectroscopy, X-ray laser diagnostics, and turbid media imaging. Avalanche photodiodes specifically designed for single photon counting semiconductor avalanche structures have been developed on the basis of various materials: Si, Ge, GaP, GaAsP, and InGaP/InGaAs at the Czech Technical University in Prague during the last 20 years. They have been tailored for numerous applications. Trends in demand are focused on detection array construction recently. Even extremely small arrays containing a few cells are of great importance for users. Electrical crosstalk between individual gating and quenching circuits and optical crosstalk between individual detecting cells are serious limitation for array design and performance. Optical crosstalk is caused by the parasitic light emission of the avalanche which accompanies the photon detection process. We have studied in detail the optical emission of the avalanche photon counting structure in the silicon- and gallium-based photodiodes. The timing properties and spectral distribution of the emitted light have been measured for different operating conditions to quantify optical crosstalk. We conclude that optical crosstalk is an inherent property of avalanche photodiode operated in Geiger mode. The only way to minimize optical crosstalk in avalanche photodiode array is to build active quenching circuit with minimum response time.

  3. Investigation on gallium ions impacting monolayer graphene

    International Nuclear Information System (INIS)

    In this paper, the physical phenomena of gallium (Ga+) ion impacting monolayer graphene in the nanosculpting process are investigated experimentally, and the mechanisms are explained by using Monte Carlo (MC) and molecular dynamics (MD) simulations. Firstly, the MC method is employed to clarify the phenomena happened to the monolayer graphene target under Ga+ ion irradiation. It is found that substrate has strong influence on the damage mode of graphene. The mean sputtering yield of graphene under 30 keV Ga+ ion irradiation is 1.77 and the least ion dose to completely remove carbon atoms in graphene is 21.6 ion/nm2. Afterwards, the focused ion beam over 21.6 ion/nm2 is used for the irradiation on a monolayer graphene supported by SiO2 experimentally, resulting in the nanostructures, i.e., nanodot and nanowire array on the graphene. The performances of the nanostructures are characterized by atomic force microscopy and Raman spectrum. A plasma plume shielding model is put forward to explain the nanosculpting results of graphene under different irradiation parameters. In addition, two damage mechanisms are found existing in the fabrication process of the nanostructures by using empirical MD simulations. The results can help us open the possibilities for better control of nanocarbon devices

  4. Indium Doped Zinc Oxide Thin Films Deposited by Ultrasonic Chemical Spray Technique, Starting from Zinc Acetylacetonate and Indium Chloride

    OpenAIRE

    Rajesh Biswal; Arturo Maldonado; Jaime Vega-Pérez; Dwight Roberto Acosta; María De La Luz Olvera

    2014-01-01

    The physical characteristics of ultrasonically sprayed indium-doped zinc oxide (ZnO:In) thin films, with electrical resistivity as low as 3.42 × 10−3 Ω·cm and high optical transmittance, in the visible range, of 50%–70% is presented. Zinc acetylacetonate and indium chloride were used as the organometallic zinc precursor and the doping source, respectively, achieving ZnO:In thin films with growth rate in the order of 100 nm/min. The effects of both indium concentration and the substrate tempe...

  5. Aluminium Electroplating on Steel from a Fused Bromide Electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Prabhat Tripathy; Laura Wurth; Eric Dufek; Toni Y. Gutknecht; Natalie Gese; Paula Hahn; Steven Frank; Guy Fredrickson; J Stephen Herring

    2014-08-01

    A quaternary bromide bath (LiBr-KBr-CsBr-AlBr3) was used to electro-coat aluminium on steel substrates. The electrolyte was prepared by the addition of AlBr3 into the eutectic LiBr-KBr-CsBr melt. A smooth, thick, adherent and shiny aluminium coating could be obtained with 80 wt.% AlBr3 in the ternary melt. The SEM photographs of the coated surfaces suggest the formation of thick and dense coatings with good aluminium coverage. Both salt immersion and open circuit potential measurement suggest that the coatings did display good corrosion-resistance behavior. Annealing of the coated surfaces, prior to corrosion tests, suggested the robustness of the metallic aluminium coating in preventing the corrosion of the steel surfaces. Studies also indicated that the quaternary bromide plating bath can potentially provide a better aluminium coating on both ferrous and non-ferrous metals, including complex surfaces/geometries.

  6. CERN: very large magnet with aluminium winding

    Energy Technology Data Exchange (ETDEWEB)

    Wittgenstein, F.A.

    1984-10-25

    The construction of an octagonal solenoid from trapezoidal plates of Al, 6m long and 6cm thick, assembled by electron beam welding, for installation in a laboratory 50m underground is described. The objective is to create a field of 0.5T in a volume of 1000m/sup 3/ for the L3 particle detector of the LEP accelerator project. Principal dimensions and weights of the structure are given and its three stages of implementation are described, with reference to the contributions from the Swiss aluminium industry.

  7. Friction stir welding of single crystal aluminium

    DEFF Research Database (Denmark)

    Fonda, Richard Warren; Wert, John A.; Reynolds, A.P.;

    2007-01-01

    Friction stir welds were prepared in different orientations in an aluminium single crystal. The welds were quenched to preserve the microstructure surrounding the tool and then electron backscattered diffraction was used to reveal the generation of grain boundaries and the evolution...... of crystallographic texture around the tool in each weld. The extent of both dynamic recrystallisation and conventional recrystallisation varied considerably as a function of weld orientation. As the base plate begins to interact with the deformation field surrounding the tool, regions of the single crystal rotate...

  8. Substoichiometric isotope dilution analysis of indium by liquid scintillation counting

    International Nuclear Information System (INIS)

    A sensitive and selective substoichiometric isotope dilution method for the determination of trace amounts of indium is described. The method is based on the extraction of its ion-association complex with substoichiometric amount of Aliquat-336 into toluene from 0.7 M KBr and 4.0 M H2SO4. The beta activity of indium-114 is measured by liquid scintillation counting. The counting efficiency was found to be 92%. The ease with which indium can be quantitatively collected over ferric hydroxide is put to advantage in developing the above method. The collection method in conjunction with the substoichiometric method is used to determine indium in the flue dust and zinc ore. The detection limit was found to be 0.5 μg in 100 ml of aqueous volume. (orig.)

  9. Recovering indium with sulfating roasting from copper-smelting ash

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A technology for recovering indium from Jinchuan copper-smelting ash was developed. Indium in the ash was first enriched to the leaching-slag in leaching process, and then recovered by sulfating roasting. The method included mixing the leaching-slag with sulfuric acid, making them into particles, roasting the mixture, and then leaching the calcine with hot water. Above 90% of indium in calcine could be dissolved into the leaching solution. The optimized conditions were determined as follows: the mass ratio of sulfuric acid to leaching slag was 0.1, the roasting time was about 1 to 1.5 h in the temperature range of 200-250 ℃, and the calcine was leached for 1 h with 5:1 of liquid/solid ratio at 60℃. Over 99% of indium in leaching solution was finally enriched by Zn substitution or sulfide precipitation.

  10. Rapid separation of gallium from zinc targets by thermal diffusion

    International Nuclear Information System (INIS)

    We present a simple, non-destructive and rapid method to separate radioactive gallium isotopes from a zinc target. Irradiated target foils were heated up to 400oC, that is close to the melting point of zinc. At this temperature the gallium isotopes became movable in the zinc matrix and were concentrated on the surface of the target. By dipping the foils into a weak acid, more than 60% of the radioactivity was etched off the target (thickness 100 μm) and with less than 0.5% loss of the target material. The total separation time was less than 30 min. The method can be applied with enriched zinc targets and low energy proton reactions and may, e.g. produce high amounts of positron emitting gallium isotopes (66Ga and 68Ga) by the use of accelerators available at PET-centers. (author)

  11. Gallium scintigraphy in Hansen's disease

    Energy Technology Data Exchange (ETDEWEB)

    Braga, F.J.H.N. (Hopital Henri-Mondor, 75 - Paris (France). Service de Biophysique de Medecine Nucleaire Sao Paulo Univ., SP (Brazil). Centro de Medicina Nuclear); Araejo, E.B.; Camargo, E.E. (Sao Paulo Univ., SP (Brazil). Centro de Medicina Nuclear); Tedesco-Marchesi, L.C.M.; Rivitti, M.C.M. (Sao Paulo Univ., SP (Brazil). Servicio de Dermatologia); Bouladour, H.; Galle, P. (Hopital Henri-Mondor, 75 - Paris (France). Service de Biophysique de Medecine Nucleaire)

    1991-11-01

    Gallium 67 imaging was used in 12 patients with documented Hansen's disease undergoing treatment or not in an attempt to determine the pattern of the disease. Diagnosis was confirmed by histopathology in all patients. The Mitsuda reaction was seen in all patients. Specific nuclear studies were performed when needed to evaluate particular organs better. Gallium 67 images show homogeneous, diffuse and moderate accumulation over the entire skin surface (except for the face) of untreated patients with multibacillary disease. The face skin in these cases presented homogeneous, diffuse but very marked uptake of gallium. Internal organ involvement was variable. There was a very good correlation among clinical, scintigraphical, immunological and histopathological data. The pattern of the body skin ('skin outlining') and face skin ('beard distribution') may be distinct for untreated patients with multibacillary leprosy. (orig.).

  12. Spectrofluorimetric determination of gallium with calon-carboxylic acid

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A simple and sensitive spectrofluorimetric procedure for the analysis of microquantities of gallium in alloy wasdescribed. The method is based on the formation of Ga(Ⅲ)-CCA (calon-carboxylic acid) complex. The emission of thefluorescent complex was measured at λ = 620 nm with excitation at λ = 584 nm. A good linearity was found in the galliumrange of 0.7-280 ng/mL. The precision of the method is good and the relative standard deviation is 1.9% for a gallium stan-dard solution of 70 ng/mL. The procedure was proved to be suitable in terms of accuracy and selectivity for the mi-croamount of gallium in alloy.

  13. Corrosion behavior of structural materials in liquid gallium environments

    International Nuclear Information System (INIS)

    The purpose of this work is to investigate the interaction between austenitic stainless steel such as SS-316L and liquid metals including pure Ga, Ga-14Sn-6Zn and Ga-8Sn-6Zn for the potential application of gallium for fast reactor coolants. As received and pre-oxidized specimens of SS-316L were exposed to static gallium and gallium alloys (Ga-14Sn-6Zn and Ga-8Sn-6Zn) at 500 C. degrees for up to 700 hours in air, vacuum and controlled O2 conditions. The results have shown that pre-oxidized specimens showed higher corrosion resistance than as-received specimens in terms of metal loss. The weight change and metal loss of SS-316L were generally reduced in Ga-14Sn-6Zn and Ga-8Sn-6Zn comparing to those in pure Ga. (authors)

  14. Volatilisation and oxidation of aluminium scraps fed into incineration furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Biganzoli, Laura, E-mail: laura.biganzoli@mail.polimi.it [Politecnico di Milano, Piazza L. Da Vinci 32, 20133 Milano (Italy); Gorla, Leopoldo; Nessi, Simone; Grosso, Mario [Politecnico di Milano, Piazza L. Da Vinci 32, 20133 Milano (Italy)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer Aluminium packaging partitioning in MSW incineration residues is evaluated. Black-Right-Pointing-Pointer The amount of aluminium packaging recoverable from the bottom ashes is evaluated. Black-Right-Pointing-Pointer Aluminium packaging oxidation rate in the residues of MSW incineration is evaluated. Black-Right-Pointing-Pointer 80% of aluminium cans, 51% of trays and 27% of foils can be recovered from bottom ashes. - Abstract: Ferrous and non-ferrous metal scraps are increasingly recovered from municipal solid waste incineration bottom ash and used in the production of secondary steel and aluminium. However, during the incineration process, metal scraps contained in the waste undergo volatilisation and oxidation processes, which determine a loss of their recoverable mass. The present paper evaluates the behaviour of different types of aluminium packaging materials in a full-scale waste to energy plant during standard operation. Their partitioning and oxidation level in the residues of the incineration process are evaluated, together with the amount of potentially recoverable aluminium. About 80% of post-consumer cans, 51% of trays and 27% of foils can be recovered through an advanced treatment of bottom ash combined with a melting process in the saline furnace for the production of secondary aluminium. The residual amount of aluminium concentrates in the fly ash or in the fine fraction of the bottom ash and its recovery is virtually impossible using the current eddy current separation technology. The average oxidation levels of the aluminium in the residues of the incineration process is equal to 9.2% for cans, 17.4% for trays and 58.8% for foils. The differences between the tested packaging materials are related to their thickness, mechanical strength and to the alloy.

  15. New sheet aluminium qualities for low-cost lightweight constructions; Neue Aluminium-Blechqualitaeten fuer den kosteneffizienten Leichtbau

    Energy Technology Data Exchange (ETDEWEB)

    Bloeck, M.; Furrer, P. [Novelis Technology AG, Neuhausen (Switzerland)

    2005-11-01

    Aluminium alloys used for car bodies have a wide range of material characteristics. New developments focus on selective development of material and surface characteristics for obtaining sheet aluminium qualities optimized for specific applications. These and further measures taken by Novelis are to reduce material consumption, simplify process steps in motor car manufacturing and reducing the overall system cost. (orig.)

  16. Design of the lines of aluminium drawing. Part 2; Conception des filieres de filage d'aluminium. Partie 2

    Energy Technology Data Exchange (ETDEWEB)

    Cescutti, J.P.; Ravaille, N. [Pechiney, Div. Filiage, 75 - Paris (France)

    2005-12-15

    This work is the second part of the file 'design of the lines of aluminium drawing'. It gives elements for structuring the analysis of the progress ways in the field of the design of the lines of aluminium extrusion. (O.M.)

  17. Recovery of indium from LCD screens of discarded cell phones.

    Science.gov (United States)

    Silveira, A V M; Fuchs, M S; Pinheiro, D K; Tanabe, E H; Bertuol, D A

    2015-11-01

    Advances in technological development have resulted in high consumption of electrical and electronic equipment (EEE), amongst which are cell phones, which have LCD (liquid crystal display) screens as one of their main components. These multilayer screens are composed of different materials, some with high added value, as in the case of the indium present in the form of indium tin oxide (ITO, or tin-doped indium oxide). Indium is a precious metal with relatively limited natural reserves (Dodbida et al., 2012), so it can be profitable to recover it from discarded LCD screens. The objective of this study was to develop a complete process for recovering indium from LCD screens. Firstly, the screens were manually removed from cell phones. In the next step, a pretreatment was developed for removal of the polarizing film from the glass of the LCD panels, because the adherence of this film to the glass complicated the comminution process. The choice of mill was based on tests using different equipment (knife mill, hammer mill, and ball mill) to disintegrate the LCD screens, either before or after removal of the polarizing film. In the leaching process, it was possible to extract 96.4 wt.% of the indium under the following conditions: 1.0M H2SO4, 1:50 solid/liquid ratio, 90°C, 1h, and stirring at 500 rpm. The results showed that the best experimental conditions enabled extraction of 613 mg of indium/kg of LCD powder. Finally, precipitation of the indium with NH4OH was tested at different pH values, and 99.8 wt.% precipitation was achieved at pH 7.4.

  18. Modeling of Etching Nano-surfaces of Indium Phosphide

    Directory of Open Access Journals (Sweden)

    S.L. Khrypko

    2015-03-01

    Full Text Available This paper describes a mechanism for obtaining a regular porous structure InP, which is to use the method of photoelectrochemical etching. Through the use of simulation etching at the nanoscale, it is possible to get a regular uniform grid of nanopores on the surface of indium phosphide, which allows us to understand the mechanisms and the establishment of technological regimes anodic structures indium phosphide to produce a variety of devices.

  19. Equation of state of liquid Indium under high pressure

    OpenAIRE

    Huaming Li; Yongli Sun; Mo Li

    2015-01-01

    We apply an equation of state of a power law form to liquid Indium to study its thermodynamic properties under high temperature and high pressure. Molar volume of molten indium is calculated along the isothermal line at 710K within good precision as compared with the experimental data in an externally heated diamond anvil cell. Bulk modulus, thermal expansion and internal pressure are obtained for isothermal compression. Other thermodynamic properties are also calculated along the fitted high...

  20. Pulmonary Alveolar Proteinosis in Workers at an Indium Processing Facility

    OpenAIRE

    Cummings, Kristin J.; Donat, Walter E.; Ettensohn, David B; Roggli, Victor L; Ingram, Peter; Kreiss, Kathleen

    2009-01-01

    Two cases of pulmonary alveolar proteinosis, including one death, occurred in workers at a facility producing indium-tin oxide (ITO), a compound used in recent years to make flat panel displays. Both workers were exposed to airborne ITO dust and had indium in lung tissue specimens. One worker was tested for autoantibodies to granulocytemacrophage–colonystimulating factor (GM-CSF) and found to have an elevated level. These cases suggest that inhalational exposure to ITO causes pulmonary alveol...

  1. Development of indium bumping technology through AZ9260 resist electroplating

    International Nuclear Information System (INIS)

    Indium bumping is very critical technology in the application of high-density interconnection between a FPA (focal plane array) and a Si ROIC (read-out integrated circuit) by flip-chip bonding. In this paper, the indium BGA (ball grid array) chips are prepared with an electroplating method on the Si substrate. With such a method, the first difficulty arises in removing the seed layer. Two ways, including IBE (ion beam etching) and lift-off, are adopted to overcome it. The results show that the lift-off process is effective but not IBE. During the reflow process, many indium bumps fall off the substrate. Two ways are tried to solve this problem: one is to optimize the reflow profile and the other is to thicken the wetting layer. The results show that these two ways can effectively improve such status. The barrier effects of the UBM (under bump metallization) for indium, which are Ti/Pt (300 Å/200 Å) and Ti/Pt/Au/Ep Au (300 Å/200 Å/1000 Å/4 µm), are also investigated. Experimental results indicate that both of them can be used in application of integration of the FPA and ROIC. Reliability of indium bumps with these two kinds of UBM is evaluated by the shear test. The results show that their shear strength has a significant increase after reflow. For the indium bump with UBM of Ti/Pt/Au/Ep Au (300 Å/200 Å/1000 Å/4 µm), IMC (intermetallic compounds) at the interface of Au–In can strengthen the indium bump but may change the plasticity of indium.

  2. Laser spectroscopy of gallium isotopes using the ISCOOL RFQ cooler

    CERN Multimedia

    Blaum, K; Kowalska, M; Ware, T; Procter, T J

    2007-01-01

    We propose to study the radioisotopes of gallium (Z=31) by collinear laser spectroscopy using the ISCOOL RFQ ion cooler. The proposed measurements on $^{62-83}$Ga will span both neutron-deficient and neutron-rich isotopes. Of key interest is the suggested development of a proton-skin in the neutron-deficient isotopes. The isotope shifts measured by laser spectroscopy will be uniquely sensitive to this feature. The measurements will also provide a wealth of new information on the gallium nuclear spins, static moments and nuclear charge radii.

  3. Microfluidic platforms for gallium-based liquid metal alloy

    Science.gov (United States)

    Kim, Daeyoung

    As an alternative to toxic mercury, non-toxic gallium-based liquid metal alloy has been gaining popularity due to its higher thermal and electrical conductivities, and low toxicity along with liquid property. However, it is difficult to handle as the alloy becomes readily oxidized in atmospheric air environment. This instant oxidation causes the gallium-based liquid metal alloy to wet almost any solid surface. Therefore, it has been primarily limited to applications which rely only on its deformability, not on its mobility. In this research, various approaches to mobilize gallium-based liquid metal alloy were investigated. Multi-scale surface patterned with polydimethylsiloxane (PDMS) micro pillar array showed super-lyophobic property against gallium-based liquid metal alloy by minimizing the contact area between the solid surface and the liquid metal, and it was expanded to a three-dimensional tunnel shaped microfluidic channel. Vertically-aligned carbon nanotube forest leads to another promising super-lyophobic surface due to its hierarchical micro/nano scale combined structures and chemical inertness. When the carbon nanotubes were transferred onto flexible PDMS by imprinting, the super-lyophobic property was still maintained even under the mechanical deformation such as stretching and bending. Alternatively, the gallium-based liquid metal can be manipulated by modifying the surface of liquid metal itself. With chemical reaction with HCl 'vapor', the oxidized surface (mainly Ga2O3/Ga2O) of gallium-based liquid metal was converted to GaCl3/InCl 3 resulting in the recovery of non-wetting characteristics. Paper which is intrinsically porous is attractive as a super-lyophobic surface and it was found that hydrochloric acid (HCl) impregnation enhanced the anti-wetting property by the chemical reaction. As another alternative method, by coating the viscoelastic oxidized surface of liquid metal with ferromagnetic materials (CoNiMnP or Fe), it showed non

  4. Magnetostriction and Magnetic Heterogeneities in Iron-Gallium

    DEFF Research Database (Denmark)

    Laver, Mark; Mudivarthi, C.; Cullen, J.R.;

    2010-01-01

    Iron-gallium alloys Fe1-xGax exhibit an exceptional increase in magnetostriction with gallium content. We present small-angle neutron scattering investigations on a Fe0.81Ga0.19 single crystal. We uncover heterogeneities with an average spacing of 15 nm and with magnetizations distinct from...... the matrix. The moments in and around the heterogeneities are observed to reorient with an applied magnetic field or mechanical strain. We discuss the possible roles played by nanoscale magnetic heterogeneities in the mechanism for magnetostriction in this material. © 2010 The American Physical Society...

  5. Determination of gallium, scandium, and iron in laterite

    International Nuclear Information System (INIS)

    Quantitative analyses of gallium, scandium and iron in laterite of 149 samples were determined by method of Instrumental Neutron Activation Analysis (INAA). The experiments were taken at the Rotary Specimen Racks of the Thai Research Reactor TRR-1/M1. The studied parameters for quantitative analysis are: time of neutron irradiation, decay time, time of measurement and photopeak. The result shows the range of contents as following: 9 ppm to 73 ppm for gallium, 7 ppm to 316 ppm for scandium and 3.37% to 36.80% for iron

  6. First results from the Soviet-American Gallium Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Abazov, A.I.; Abdurashitov, D.N.; Anosov, O.L.; Eroshkina, L.A.; Faizov, E.L.; Gavrin, V.N.; Kalikhov, A.V.; Knodel, T.V.; Knyshenko, I.I.; Kornoukhov, V.N.; Mezentseva, S.A.; Mirmov, I.N.; Ostrinsky, A.I.; Petukhov, V.V.; Pshukov, A.M.; Revzin, N.Ye.; Shikhin, A.A.; Timofeyev, P.V.; Veretenkin, E.P.; Vermul, V.M.; Zakharov, Yu.; Zatsepin, G.T.; Zhandarov, V.I. (AN SSSR, Moscow (USSR). Inst. Yadernykh Issledovanij); Bowles, T.J.; Cleveland, B.T.; Elliott, S.R.; O' Brien, H.A.; Wark, D.L.; Wilkerson, J.F. (Los Alamos National Lab., NM (USA)); Davis, R. Jr.; Lande, K. (Pennsylvania Univ., Philadelphia (USA)); Cherry, M.L. (Louisiana State Univ., Baton Rouge (USA)); Kouzes, R.T. (Princeton Univ., NJ (USA))

    1991-04-01

    The Soviet-American Gallium Experiment is the first experiment able to measure the dominant flux of low energy p-p solar neutrinos. Four extractions made during January to May 1950 from 30 tons of gallium have been counted and indicate that the flux is consistent with 0 SNU and is less than 72 SNU (68% GL) and less than 138 SNU (95% CL). This is to be compared wit h the flux of 132 SNU predicted by the Standard Solar Model. (orig.).

  7. Latest results from the Soviet-American gallium experiment

    Energy Technology Data Exchange (ETDEWEB)

    Gavrin, V.N.; Anosov, O.L.; Faizov, E.L.; Kalikhov, A.V.; Knodel, T.V.; Knyshenko, I.I.; Kornoukhov, V.N.; Mirmov, I.N.; Ostrinsky, A.V.; Pshukov, A.M.; Shikhin, A.A.; Timofeyev, P.V.; Veretenkin, E.P.; Vermul, V.M.; Zatsepin, G.T. (Institute for Nuclear Research, Russian Academy of Sciences, Moscow 117312 (Russian Federation)); Bowles, T.J.; Elliott, S.R.; Nico, J.S.; O' Brien, H.A.; Wark, D.L.; Wilkerson, J.F. (Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)); Cleveland, B.T.; Davis, R. Jr.; Lande, K. (University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)); Cherry, M.L. (Louisiana State University, Baton Rouge, Louisiana 70803 (United States)); Kouzes, R.T. (Princeton University, Princeton, New Jersey 08544 (United States))

    1992-02-01

    A radiochemical [sup 71]Ga-[sup 71]Ge experiment to determine the primary flux of neutrinos from the Sun began measurements of the solar neutrino flux at the Baksan Neutrino Observatory in 1990. The number of [sup 71]Ge atoms extracted from 30 tons of gallium in 1990 and from 57 tons of gallium in 1991 was measured in twelve runs during the period of January 1990 to December 1991. The combined 1990 and 1991 data sets give a value of 58+17/-24 (stat)[plus minus]14 (syst) SNU. This is to be compared with 132 SNU predicted by the Standard Solar Model.

  8. Latest results from the Soviet-American gallium experiment

    Energy Technology Data Exchange (ETDEWEB)

    Gavrin, V.N.; Anosov, O.L.; Faizov, E.L.; Kalikhov, A.V.; Knodel, T.V.; Knyshenko, I.I.; Kornoukhov, V.N.; Mirmov, I.N.; Ostrinsky, A.V.; Pshukov, A.M.; Shikhin, A.A.; Timofeyev, P.V.; Veretenkin, E.P.; Vermul, V.M.; Zatsepin, G.T. [AN SSSR, Moscow (Russian Federation). Inst. Yadernykh Issledovanij; Bowles, T.J.; Elliott, S.R.; Nico, J.S.; O`Brien, H.A.; Wark, D.L.; Wilkerson, J.F. [Los Alamos National Lab., NM (United States); Cleveland, B.T.; Davis, R. Jr.; Lande, K. [Pennsylvania Univ., Philadelphia, PA (United States); Cherry, M.L. [Louisiana State Univ., Baton Rouge, LA (United States); Kouzes, R.T. [Princeton Univ., NJ (United States)

    1992-12-01

    A radiochemical {sup 71}Ga-{sup 7l}Ge experiment to determine the primary flux of neutrinos from the Sun began measurements of the solar neutrino flux at the Baksan Neutrino Observatory in 1990. The number of {sup 71}Ge atoms extracted from 30 tons of gallium in 1990 and from 57 tons of gallium in 1991 was measured in twelve runs during the period of January 1990 to December 1991. The combined 1990 and 1991 data sets give a value of 58 +17/{minus}24 (stat) {plus_minus} 14 (syst) SNU. This is to be compared with 132 SNU predicted by the Standard Solar Model.

  9. Study on indium leaching from mechanically activated hard zinc residue

    Directory of Open Access Journals (Sweden)

    Yao J.H.

    2011-01-01

    Full Text Available In this study, changes in physicochemical properties and leachability of indium from mechanically activated hard zinc residue by planetary mill were investigated. The results showed that mechanical activation increased specific surface area, reaction activity of hard zinc residue, and decreased its particle size, which had a positive effect on indium extraction from hard zinc residue in hydrochloric acid solution. Kinetics of indium leaching from unmilled and activated hard zinc residue were also investigated, respectively. It was found that temperature had an obvious effect on indium leaching rate. Two different kinetic models corresponding to reactions which are diffusion controlled, [1-(1- x1/3]2=kt and (1-2x/3-(1-x2/3=kt were used to describe the kinetics of indium leaching from unmilled sample and activated sample, respectively. Their activation energies were determined to be 17.89 kJ/mol (umilled and 11.65 kJ/mol (activated within the temperature range of 30°C to 90°C, which is characteristic for a diffusion controlled process. The values of activation energy demonstrated that the leaching reaction of indium became less sensitive to temperature after hard zinc residue mechanically activated by planetary mill.

  10. Aluminium matrix composites: Challenges and opportunities

    Indian Academy of Sciences (India)

    M K Surappa

    2003-02-01

    Aluminium matrix composites (AMCs) refer to the class of light weight high performance aluminium centric material systems. The reinforcement in AMCs could be in the form of continuous/discontinuous fibres, whisker or particulates, in volume fractions ranging from a few percent to 70%. Properties of AMCs can be tailored to the demands of different industrial applications by suitable combinations of matrix, reinforcement and processing route. Presently several grades of AMCs are manufactured by different routes. Three decades of intensive research have provided a wealth of new scientific knowledge on the intrinsic and extrinsic effects of ceramic reinforcement vis-a-vis physical, mechanical, thermo-mechanical and tribological properties of AMCs. In the last few years, AMCs have been utilised in high-tech structural and functional applications including aerospace, defence, automotive, and thermal management areas, as well as in sports and recreation. It is interesting to note that research on particle-reinforced cast AMCs took root in India during the 70’s, attained industrial maturity in the developed world and is currently in the process of joining the mainstream of materials. This paper presents an overview of AMC material systems on aspects relating to processing, microstructure, properties and applications.

  11. Reactions on carbon anodes in aluminium electrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Eidet, Trygve

    1997-12-31

    The consumption of carbon anodes and energy in aluminium electrolysis is higher than what is required theoretically. This thesis studies the most important of the reactions that consume anode materials. These reactions are the electrochemical anode reaction and the airburn and carboxy reactions. The first part of the thesis deals with the kinetics and mechanism of the electrochemical anode reaction using electrochemical impedance spectroscopy. The second part deals with air and carboxy reactivity of carbon anodes and studies the effects of inorganic impurities on the reactivity of carbon anodes in the aluminium industry. Special attention is given to sulphur since its effect on the carbon gasification is not well understood. Sulphur is always present in anodes, and it is expected that the sulphur content of available anode cokes will increase in the future. It has also been suggested that sulphur poisons catalyzing impurities in the anodes. Other impurities that were investigated are iron, nickel and vanadium, which are common impurities in anodes which have been reported to catalyze carbon gasification. 88 refs., 92 figs., 24 tabs.

  12. Effects of varying indium composition on the thermoelectric properties of In x Ga1- x Sb ternary alloys

    Science.gov (United States)

    Nirmal Kumar, V.; Arivanandan, M.; Koyoma, T.; Udono, H.; Inatomi, Y.; Hayakawa, Y.

    2016-10-01

    In x Ga1- x Sb ( x = 0-1), a III-V ternary alloy, was grown by melt solidification process. The effects of varying indium composition on the thermoelectric properties of In x Ga1- x Sb polycrystals were studied for the first time. The segregations of indium and gallium elements were observed in the grown crystals, and the defects present in crystals were revealed by etching process. Room-temperature Raman measurement revealed that the dominant optical modes of phonon vibrations in InSb and GaSb binaries were suppressed in In x Ga1- x Sb ternaries. The in-phase vibrations of acoustic mode phonons were scattered more effectively in In x Ga1- x Sb by the present defects, and the relative value of lattice thermal conductivity was reduced. Thus, the thermal conductivity of InSb and GaSb binaries was drastically reduced in In x Ga1- x Sb by alloy scattering. InSb indicated the highest ZT 0.51 because of its higher power factor 70 µW/cmK2. Next to InSb, In0.8Ga0.2Sb had higher ZT value of 0.29 at 600 K among the In x Ga1- x Sb ternaries. The ZT of In0.8Ga0.2Sb was increased about 30 times than that of GaSb by the increase of power factor as well as the decrease of thermal conductivity.

  13. INTEROGATION OF THE MANUFACTURING ROUTE OF ALUMINIUM AA 1050 USED IN LITHOGRAPHIC APPLICATION

    OpenAIRE

    Witkowska, Malgorzata Danuta

    2013-01-01

    The aluminium AA1050 alloy, known as commercially pure aluminium, contains 99.5% Al, together with Fe and Si as major alloying elements. During fabrication of aluminium substrates for lithographic printing plates in Bridgnorth Aluminium Ltd, the AA 1050 aluminium alloy proceeds through various stages of thermomechanical processing, with the conditions at each processing stage influencing the microstructure of the final coil. Because of its specific gravity, tensile strength, surface performa...

  14. Preparation of Aluminium Oxynitride by Carbothermal Reduction of Aluminium Oxide in a Flowing N2 Atmosphere

    Institute of Scientific and Technical Information of China (English)

    LIYa-wei; YUANRun-zhang; 等

    1996-01-01

    Carbothermal reduction of alumina into aluminium oxynitride(AlON) spinel in a flowing nitrogen atmosphere was studied.The effects of Al2O3/C ratio temperature,soaking time,heating rate molding pressure of samples,and nitrogen flow rate on reactions were investigated.Then the stability of AlON was elucidated and AlON wa confirmed as an intermediate compound in reduction of alumina.

  15. Aluminium: Aluminij: kovina izbire: the metal of choice:

    OpenAIRE

    Gándara, María Josefa Freiría

    2013-01-01

    This article summarizes the importance of aluminium as the metal of choice formany applications. Aluminium is a lightweight, durable metal. It is silvery in appearance when freshly cut, is a good conductor of heat and electricity, and is easily shaped by moulding and extruding. Aluminium has two main advantages when compared with other metals. Firstly, it has a low density, about one-third that of iron and copper. Secondly, although it reacts rapidly with the oxygen in air, it forms a thin, t...

  16. Optimization of Magnesium Metal into Commercially Pure Aluminium

    Directory of Open Access Journals (Sweden)

    Vandana J Rao

    2014-02-01

    Full Text Available The present investigation, involve development of Al-Mg systems by addition of magnesium into commercially pure aluminium. The amounts of magnesium added into commercially pure aluminium are of 1 and 2 wt%. The recoveries of magnesium are around 85-90%.Remaining Mg react with oxygen and float on the liquid aluminium. Presence of magnesium creates two phenomena. One is solid solution hardening and other is intermetallics formation. Both the phenomena checked by microstructural changes and by measuring the electrical conductivity values. By increasing the Mg, content mechanical properties (hardness and tensile strength increases and electrical conductivity decreases.

  17. Effect of pressurized steam on AA1050 aluminium

    DEFF Research Database (Denmark)

    Jariyaboon, Manthana; Møller, Per; Ambat, Rajan

    2012-01-01

    Purpose - The purpose of this paper is to understand the effect of pressurized steam on surface changes, structures of intermetallic particles and corrosion behavior of AA1050 aluminium. Design/methodology/approach - Industrially pure aluminium (AA1050, 99.5 per cent) surfaces were exposed...... reactivities was observed due to the formation of the compact oxide layer. Originality/value - This paper reveals a detailed investigation of how pressurized steam can affect the corrosion behaviour of AA1050 aluminium and the structure of Fe-containing intermetallic particles....

  18. Effect of filtration on reoxidation proceses in aluminium alloys

    Directory of Open Access Journals (Sweden)

    D. Bolibruchova

    2010-01-01

    Full Text Available This article is focused on reoxidation processes during filtration of aluminium alloys. Many of our experimental works pointed out, that using filtration media placed in gating system causes reoxidation of poured aluminium alloy. Main aim of our latest work was to validate our arguments, that filter in gating system can be considered as obstacle for continuous pouring, with help of computer simulations. This article is only a small part of our researches focused on reoxidation processes during filtration of aluminium alloys.

  19. Corrosion issues of powder coated AA6060 aluminium profiles

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Valgarðsson, Smári; Jellesen, Morten Stendahl;

    2015-01-01

    In this study detailed microstructural investigation of the reason for unexpected corrosion of powder coated aluminium alloy AA6060 windows profiles has been performed. The results from this study reveals that the failure of the window profiles was originated from the surface defects present...... on the extruded AA6060 aluminium profile after metallurgical process prior to powder coating. Surface defects are produced due to intermetallic particles in the alloy, which disturb the flow during the extrusion process. The corrosion mechanism leading to the failure of the powder coated AA6060 aluminium profiles...

  20. Thickness Evaluation of Aluminium Plate Using Pulsed Eddy Current Technique

    Science.gov (United States)

    Singh, Gurpartap; Bapat, Harsh Madhukar; Singh, Bhanu Pratap; Bandyopadhyay, Manojit; Puri, Rakesh Kumar; Badodkar, Deepak Narayanrao

    2013-10-01

    This paper describes a pulsed eddy current (PEC) based non-destructive testing system used for detection of thickness variation in aluminium plate. A giant magneto-resistive sensor has been used instead of pick up coil for detecting resultant magnetic field. The PEC response signals obtained from 1 to 5 mm thickness change in aluminium plate were investigated. Two time domain features, namely peak value and time to peak, of PEC response were used for extracting information about thickness variation in aluminium plate. The variation of peak value and time to peak with thickness was compared. A program was developed to display the thickness variation of the tested sample.

  1. Radiation-induced creep of copper, aluminium and their alloys

    International Nuclear Information System (INIS)

    The results of creep studies on copper, aluminium and their alloys with and without neutron irradiation are presented. The experiments are carried out at the WWR-K reactor at the neutron fluence of 1.4.1016 n/m2.s (2.5.1016 n/m2.s, E>0.1 MeV). Polycrystalline copper (99.99 and 99.95%), aluminium (99.99%) and the alloys of copper with 4 at% of titanium, of aluminium with 4.2% of copper are studied within the temperature interval 0.31-0.51 Tm. (orig.)

  2. Study of fatigue behaviour of 7475 aluminium alloy

    Indian Academy of Sciences (India)

    B B Verma; J D Atkinson; M Kumar

    2001-04-01

    Fatigue properties of a thermomechanically treated 7475 aluminium alloy have been studied in the present investigation. The alloy exhibited superior fatigue life compared to conventional structural aluminium alloys and comparable stage II crack growth rate. It was also noticed that the fatigue crack initiated from a surface grain and the crack extension was dominated by ductile striations. Analysis also revealed that this alloy possessed fracture toughness and tensile properties superior to that noticed with other structural aluminium alloys. Therefore the use of this alloy can safely reduce the overall weight of the aircraft.

  3. Gallium Nitride MMICs for mm-Wave Power Operation

    NARCIS (Netherlands)

    Quay, R.; Maroldt, S.; Haupt, C.; Heijningen, M. van; Tessmann, A.

    2009-01-01

    In this paper a Gallium Nitride MMIC technology for high-power amplifiers between 27 GHz and 101 GHz based on 150 nm- and 100 nm-gate technologies is presented. The GaN HEMT MMICs are designed using coplanar waveguide transmission-line-technology on 3-inch semi-insulating SiC substrates. The measure

  4. Abnormal gallium scintigraphy in pulmonary alveolar proteinosis (PAP)

    International Nuclear Information System (INIS)

    A patient with medulloblastoma of the cerebellum developed dyspnea and hypoxemia. Pulmonary function tests showed decreased lung volume and diffusing capacity, while the chest radiographs initially showed only mild interstitial infiltrates. Repeated gallium scans showed diffuse lung uptake and diagnosis of pulmonary alveolar proteinosis was made by open lung biopsy

  5. Targeting Gallium to Cancer Cells through the Folate Receptor

    Directory of Open Access Journals (Sweden)

    Nerissa Viola-Villegas

    2008-01-01

    Full Text Available The development of gallium(III compounds as anti-cancer agents for both treatment and diagnosis is a rapidly developing field of research. Problems remain in exploring the full potential of gallium(III as a safe and successful therapeutic agent or as an imaging agent. One of the major issues is that gallium(III compounds have little tropism for cancer cells. We have combined the targeting properties of folic acid (FA with long chain liquid polymer poly(ethylene glycol (PEG ‘spacers’. This FA-PEG unit has been coupled to the gallium coordination complex of 1,4,7,10-tetraazacyclo-dodecane-N,N′,N′′,N′′′-tetraacetic acid (DOTA through amide linkages for delivery into target cells overexpressing the folate receptor (FR. In vitro cytotoxicity assays were conducted against a multi-drug resistant ovarian cell line (A2780/AD that overexpresses the FR and contrasted against a FR free Chinese hamster ovary (CHO cell line. Results are rationalized taking into account stability studies conducted in RPMI 1640 media and HEPES buffer at pH 7.4.

  6. Optical properties of strained wurtzite gallium phosphide nanowires

    NARCIS (Netherlands)

    Greil, J.; Assali, S.; Isono, Y.; Belabbes, A.; Bechstedt, F.; Valega MacKenzie, F.O.; Silov, A.Yu.; Bakkers, E.P.A.M.; Haverkort, J.E.M.

    2016-01-01

    Wurtzite gallium phosphide (WZ GaP) has been predicted to exhibit a direct bandgap in the green spectral range. Optical transitions, however, are only weakly allowed by the symmetry of the bands. While efficient luminescence has been experimentally shown, the nature of the transitions is not yet cle

  7. Abnormal gallium scintigraphy in pulmonary alveolar proteinosis (PAP)

    Energy Technology Data Exchange (ETDEWEB)

    Yeh, S.D.; White, D.A.; Stover-Pepe, D.E.; Caravelli, J.F.; Van Uitert, C.; Benua, R.S.

    1987-04-01

    A patient with medulloblastoma of the cerebellum developed dyspnea and hypoxemia. Pulmonary function tests showed decreased lung volume and diffusing capacity, while the chest radiographs initially showed only mild interstitial infiltrates. Repeated gallium scans showed diffuse lung uptake and diagnosis of pulmonary alveolar proteinosis was made by open lung biopsy.

  8. Discovery of Gallium, Germanium, Lutetium, and Hafnium Isotopes

    OpenAIRE

    J.L. Gross; Thoennessen, M

    2011-01-01

    Currently, twenty-eight gallium, thirty-one germanium, thirty-five lutetium, and thirty-six hafnium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  9. [Dimensional changes of silver and gallium-based alloy].

    Science.gov (United States)

    Ballester, R Y; Markarian, R A; Loguercio, A D

    2001-01-01

    Gallium-based dental alloys were created with the aim of solving the problem of toxicity of mercury. The material shows mechanical properties similar to those of dental amalgam, but researches point out two unfavorable characteristics: great corrosion and excessive post-setting expansion, and the latter is capable of cracking dental structures. The aim of this study was to evaluate, during 7 days, the in vitro dimensional alteration of a gallium dental alloy (Galloy, SDI, Australia), in comparison with a dental amalgam containing zinc (F400, SDI, Australia), as a function of the contact with saline solution (0.9% NaCl) during the setting period. The storage experimental conditions were: storage in dry environment, immersion in saline solution and contamination during condensation. Additionally, the effects of contamination during the trituration of dental amalgam and the effects of protecting the surface of the gallium alloy with a fluid resin were studied. Specimens were stored at 37 degrees C +/- 1 degree C, and measuring was carried out, sequentially, every 24 h during 7 days. When the gallium alloy was either contaminated or immersed, an expansion significantly greater than that observed in the other experimental conditions was noticed after 7 days. The application of a fluid resin to protect the surface of the cylinders was able to avoid the increase in expansion caused by superficial moisture. The amalgam alloy did not show significant dimensional alterations, except when it was contaminated during trituration.

  10. Fabrication challenges for indium phosphide microsystems

    International Nuclear Information System (INIS)

    From the inception of III–V microsystems, monolithically integrated device designs have been the motivating drive for this field, bringing together the utility of single-chip microsystems and conventional fabrication techniques. Indium phosphide (InP) has a particular advantage of having a direct bandgap within the low loss telecommunication wavelength (1550 nm) range, able to support passive waveguiding and optical amplification, detection, and generation depending on the exact alloy of In, P, As, Ga, or Al materials. Utilizing epitaxy, one can envision the growth of a substrate that contains all of the components needed to establish a single-chip optical microsystem, containing detectors, sources, waveguides, and mechanical structures. A monolithic InP MEMS system has, to our knowledge, yet to be realized due to the significant difficulties encountered when fabricating the integrated devices. In this paper we present our own research and consolidate findings from other research groups across the world to give deeper insight into the practical aspects of InP monolithic microsystem development: epitaxial growth of InP-based alloys, etching techniques, common MEMS structures realized in InP, and future applications. We pay special attention to shedding light on considerations that must be taken when designing and fabricating a monolithic InP MEMS device. (topical review)

  11. Fabrication challenges for indium phosphide microsystems

    Science.gov (United States)

    Siwak, N. P.; Fan, X. Z.; Ghodssi, R.

    2015-04-01

    From the inception of III-V microsystems, monolithically integrated device designs have been the motivating drive for this field, bringing together the utility of single-chip microsystems and conventional fabrication techniques. Indium phosphide (InP) has a particular advantage of having a direct bandgap within the low loss telecommunication wavelength (1550 nm) range, able to support passive waveguiding and optical amplification, detection, and generation depending on the exact alloy of In, P, As, Ga, or Al materials. Utilizing epitaxy, one can envision the growth of a substrate that contains all of the components needed to establish a single-chip optical microsystem, containing detectors, sources, waveguides, and mechanical structures. A monolithic InP MEMS system has, to our knowledge, yet to be realized due to the significant difficulties encountered when fabricating the integrated devices. In this paper we present our own research and consolidate findings from other research groups across the world to give deeper insight into the practical aspects of InP monolithic microsystem development: epitaxial growth of InP-based alloys, etching techniques, common MEMS structures realized in InP, and future applications. We pay special attention to shedding light on considerations that must be taken when designing and fabricating a monolithic InP MEMS device.

  12. Indium Antimonide Nanowires: Synthesis and Properties

    Science.gov (United States)

    Shafa, Muhammad; Akbar, Sadaf; Gao, Lei; Fakhar-e-Alam, Muhammad; Wang, Zhiming M.

    2016-03-01

    This article summarizes some of the critical features of pure indium antimonide nanowires (InSb NWs) growth and their potential applications in the industry. In the first section, historical studies on the growth of InSb NWs have been presented, while in the second part, a comprehensive overview of the various synthesis techniques is demonstrated briefly. The major emphasis of current review is vapor phase deposition of NWs by manifold techniques. In addition, author review various protocols and methodologies employed to generate NWs from diverse material systems via self-organized fabrication procedures comprising chemical vapor deposition, annealing in reactive atmosphere, evaporation of InSb, molecular/ chemical beam epitaxy, solution-based techniques, and top-down fabrication method. The benefits and ill effects of the gold and self-catalyzed materials for the growth of NWs are explained at length. Afterward, in the next part, four thermodynamic characteristics of NW growth criterion concerning the expansion of NWs, growth velocity, Gibbs-Thomson effect, and growth model were expounded and discussed concisely. Recent progress in device fabrications is explained in the third part, in which the electrical and optical properties of InSb NWs were reviewed by considering the effects of conductivity which are diameter dependent and the applications of NWs in the fabrications of field-effect transistors, quantum devices, thermoelectrics, and detectors.

  13. Aluminium content of some foods and food products in the USA, with aluminium food additives.

    Science.gov (United States)

    Saiyed, Salim M; Yokel, Robert A

    2005-03-01

    The primary objective was to determine the aluminium (Al) content of selected foods and food products in the USA which contain Al as an approved food additive. Intake of Al from the labeled serving size of each food product was calculated. The samples were acid or base digested and analysed for Al using electrothermal atomic absorption spectrometry. Quality control (QC) samples, with matrices matching the samples, were generated and used to verify the Al determinations. Food product Al content ranged from Cheese in a serving of frozen pizzas had up to 14 mg of Al, from basic sodium aluminium phosphate; whereas the same amount of cheese in a ready-to-eat restaurant pizza provided 0.03-0.09 mg. Many single serving packets of non-dairy creamer had approximately 50-600 mg Al kg(-1) as sodium aluminosilicate, providing up to 1.5 mg Al per serving. Many single serving packets of salt also had sodium aluminosilicate as an additive, but the Al content was less than in single-serving non-dairy creamer packets. Acidic sodium aluminium phosphate was present in many food products, pancakes and waffles. Baking powder, some pancake/waffle mixes and frozen products, and ready-to-eat pancakes provided the most Al of the foods tested; up to 180 mg/serving. Many products provide a significant amount of Al compared to the typical intake of 3-12 mg/day reported from dietary Al studies conducted in many countries. PMID:16019791

  14. Numerical Simulation on Electrical-Thermal Properties of Gallium-Nitride-Based Light-Emitting Diodes Embedded in Board

    Directory of Open Access Journals (Sweden)

    Xing-ming Long

    2012-01-01

    Full Text Available The electrical-thermal characteristics of gallium-nitride- (GaN- based light-emitting diodes (LED, packaged by chips embedded in board (EIB technology, were investigated using a multiphysics and multiscale finite element code, COMSOL. Three-dimensional (3D finite element model for packaging structure has been developed and optimized with forward-voltage-based junction temperatures of a 9-chip EIB sample. The sensitivity analysis of the simulation model has been conducted to estimate the current and temperature distribution changes in EIB LED as the blue LED chip (substrate, indium tin oxide (ITO, packaging structure (bonding wire and chip numbers, and system condition (injection current changed. This method proved the reliability of simulated results in advance and useful material parameters. Furthermore, the method suggests that the parameter match on Shockley's equation parameters, Rs, nideal, and Is, is a potential method to reduce the current crowding effect for the EIB LED. Junction temperature decreases by approximately 3 K to 10 K can be achieved by substrate thinning, ITO, and wire bonding. The nonlinear-decreasing characteristics of total thermal resistance that decrease with an increase in chip numbers are likely to improve the thermal performance of EIB LED modules.

  15. Gallium Oxide Nanostructures for High Temperature Sensors

    Energy Technology Data Exchange (ETDEWEB)

    Chintalapalle, Ramana V. [Univ. of Texas, El Paso, TX (United States)

    2015-04-30

    Gallium oxide (Ga2O3) thin films were produced by sputter deposition by varying the substrate temperature (Ts) in a wide range (Ts=25-800 °C). The structural characteristics and electronic properties of Ga2O3 films were evaluated using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDS), Rutherford backscattering spectrometry (RBS) and spectrophotometric measurements. The effect of growth temperature is significant on the chemistry, crystal structure and morphology of Ga2O3 films. XRD and SEM analyses indicate that the Ga2O3 films grown at lower temperatures were amorphous while those grown at Ts≥500 oC were nanocrystalline. RBS measurements indicate the well-maintained stoichiometry of Ga2O3 films at Ts=300-800 °C. The electronic structure determination indicated that the nanocrystalline Ga2O3films exhibit a band gap of ~5 eV. Tungsten (W) incorporated Ga2O3 films were produced by co-sputter deposition. W-concentration was varied by the applied sputtering-power. No secondary phase formation was observed in W-incorporated Ga2O3 films. W-induced effects were significant on the structure and electronic properties of Ga2O3 films. The band gap of Ga2O3 films without W-incorporation was ~5 eV. Oxygen sensor characteristics evaluated using optical and electrical methods indicate a faster response in W-doped Ga2O3 films compared to intrinsic Ga2O3 films. The results demonstrate the applicability of both intrinsic and W-doped Ga-oxide films for oxygen sensor application at temperatures ≥700 °C.

  16. Nonlinear radiation response of n-doped indium antimonide and indium arsenide in intense terahertz field

    Science.gov (United States)

    Gong, Jiao-Li; Liu, Jin-Song; Chu, Zheng; Yang, Zhen-Gang; Wang, Ke-Jia; Yao, Jian-Quan

    2016-10-01

    The nonlinear radiation responses of two different n-doped bulk semiconductors: indium antimonide (InSb) and indium arsenide (InAs) in an intense terahertz (THz) field are studied by using the method of ensemble Monte Carlo (EMC) at room temperature. The results show that the radiations of two materials generate about 2-THz periodic regular spectrum distributions under a high field of 100 kV/cm at 1-THz center frequency. The center frequencies are enhanced to about 7 THz in InSb, and only 5 THz in InAs, respectively. The electron valley occupancy and the percentage of new electrons excited by impact ionization are also calculated. We find that the band nonparabolicity and impact ionization promote the generation of nonlinear high frequency radiation, while intervalley scattering has the opposite effect. Moreover, the impact ionization dominates in InSb, while impact ionization and intervalley scattering work together in InAs. These characteristics have potential applications in up-convension of THz wave and THz nonlinear frequency multiplication field. Project supported by the National Natural Science Foundation of China (Grant Nos. 11574105 and 61177095), the Natural Science Foundation of Hubei Province, China (Grant Nos. 2012FFA074 and 2013BAA002), the Wuhan Municipal Applied Basic Research Project, China (Grant No. 20140101010009), and the Fundamental Research Funds for the Central Universities, China (Grant Nos. 2013KXYQ004 and 2014ZZGH021).

  17. Adsorption of aluminium by stream particulates.

    Science.gov (United States)

    Tipping, E; Ohnstad, M; Woof, C

    1989-01-01

    An experimental study was made of the adsorption of aluminium by fine particulates from Whitray Beck, a hill stream in NW England. Adsorption increased with Al(3) activity, pH and concentration of particles, and could be quantitatively described by the empirical equation: [Formula: see text] [particles] where square brackets indicate concentrations, curly brackets, activities, and alpha, beta and gamma are constants with values of 5.14x10(-10) (mol litre(-1))(2.015) (g particles litre(-1))(-1), 0.457, and 1.472, respectively. For the experimental data, the equation gave a correlation ratio of 0.99. The equation accounts reasonably well for the adsorption of Al by particulates from seven other streams. In applying the equation, it must be borne in mind that the desorption kinetics of Al depend on pH, and rapid reversibility (or=10%) of total monomeric Al. PMID:15092454

  18. Mechanical behaviour of aluminium-lithium alloys

    Indian Academy of Sciences (India)

    N Eswara Prasad; A A Gokhale; P Rama Rao

    2003-02-01

    Aluminium-lithium alloys hold promise of providing a breakthrough response to the crying need for lightweight alloys for use as structurals in aerospace applications. Considerable worldwide research has gone into developing a range of these alloys over the last three decades. As a result, substantial understanding has been developed of the microstructure-based micromechanisms of strengthening, of fatigue and fracture as well as of anisotropy in mechanical properties. However, these alloys have not yet greatly displaced the conventionally used denser Al alloys on account of their poorer ductility, fracture toughness and low cycle fatigue resistance. This review aims to summarise the work pertaining to study of structure and mechanical properties with a view to indicate the directions that have been and can be pursued to overcome property limitations.

  19. Optical Properties of Indium Doeped ZnO Nanowires

    Directory of Open Access Journals (Sweden)

    Tsung-Shine Ko

    2015-01-01

    Full Text Available We report the synthesis of the ZnO nanowires (NWs with different indium concentrations by using the thermal evaporation method. The gold nanoparticles were used as the catalyst and were dispersed on the silicon wafer to facilitate the growth of the ZnO NWs. High resolution transmission electron microscopy confirms that the ZnO NWs growth relied on vapor-liquid-solid mechanism and energy dispersion spectrum detects the atomic percentages of indium in ZnO NWs. Scanning electron microscopy shows that the diameters of pure ZnO NWs range from 20 to 30 nm and the diameters of ZnO:In were increased to 50–80 nm with increasing indium doping level. X-ray diffraction results point out that the crystal quality of the ZnO NWs was worse with doping higher indium concentration. Photoluminescence (PL study of the ZnO NWs exhibited main photoemission at 380 nm due to the recombination of excitons in near-band-edge (NBE. In addition, PL results also indicate the slightly blue shift and PL intensity decreasing of NBE emission from the ZnO NWs with higher indium concentrations could be attributed to more donor-induced trap center generations.

  20. Aluminium leaching from red mud by filamentous fungi.

    Science.gov (United States)

    Urík, Martin; Bujdoš, Marek; Milová-Žiaková, Barbora; Mikušová, Petra; Slovák, Marek; Matúš, Peter

    2015-11-01

    This contribution investigates the efficient and environmentally friendly aluminium leaching from red mud (bauxite residue) by 17 species of filamentous fungi. Bioleaching experiments were examined in batch cultures with the red mud in static, 7-day cultivation. The most efficient fungal strains in aluminium bioleaching were Penicillium crustosum G-140 and Aspergillus niger G-10. The A. niger G-10 strain was capable to extract up to approximately 141 mg·L(-1) of aluminium from 0.2 g dry weight red mud. Chemical leaching with organic acids mixture, prepared according to A. niger G-10 strain's respective fungal excretion during cultivation, proved that organic acids significantly contribute to aluminium solubilization from red mud.