Showing papers on "Antimony published in 1990"
TL;DR: In this paper, Boron, Aluminum, Gallium, Indium, and Thallium are classified as the Halogens: Fluorine, Chlorine, Bromine, and Iodine.
164 citations
TL;DR: In this paper, As and Sb were found to be predominant forms in the waters of the South Fork and Main Stem of the Coeur d'Alene River, whereas the North Fork generally had higher As(V) concentrations.
Abstract: Sediments from the Main Stem and the South Fork of the Coeur d'Alene River are contaminated with As, Sb, and other heavy metals from the local mining operations. Water samples from the South Fork and the Main Stem showed high levels of As (0.11-1.64 {mu}g/L) and Sb (0.23-8.25 {mu}g/L) relative to those from the North Fork (0.26 {mu}g/O As and 0.17 {mu}g/L Sb). Arsenic (III) was found to be the predominant form in the waters of the South Fork and Main Stem of the Coeur d'Alene River, whereas the North Fork generally had higher As(V) concentrations. The major inorganic Sb species was Sb(V) in all three branches of the river. Leaching of As and Sb species from the contaminated Main Stem sediments depends on the pH values of the water as well as on the free iron oxides and manganese oxides present in the sediments. Factors controlling the distribution and mobilization of As and Sb species in this aquatic environments are discussed.
119 citations
TL;DR: Field exposure of grass in pots of uncontaminated soil and a laboratory experiment using soils from near the smelter suggested that the antimony in vegetation was largely due to continued aerial deposition and not to uptake from soil.
96 citations
TL;DR: The most extensive series of compounds that fall within this section are the anionic iron-carbonyl-thallium clusters as mentioned in this paper, which include gallium, indium, thallium, germanium, tin, lead, antimony, and tellurium.
Abstract: Publisher Summary This chapter discusses the transition metal complexes incorporating the atoms of the heavier main-group elements and complexes containing gallium, indium, thallium, germanium, tin, lead, antimony, bismuth, and tellurium, although reference to compounds involving other elements is made where appropriate. It focuses on the general aspects of synthesis, structure, bonding, reactivity, and trends. The most extensive series of compounds that fall within this section are the anionic iron–carbonyl–thallium clusters. The simplest class of complexes involving the Group 6 transition metals are those represented by the general formula E(MLn)2, where MLn represents a 17-electron fragment, containing a two-coordinate and formally divalent main-group element. No homonuclear complexes containing more than three transition metal fragments have been described, although a number of mixed-metal species are known. Many complexes involving iron are known, mostly clusters containing iron–carbonyl fragments, and reports for some come from the early years of metal-cluster chemistry. Three distinct types of tetracobalt germanium compounds are described. There are a sufficiently large number of complexes, mainly of germanium, containing more than one type of transition metal, to warrant a separate discussion. Trigonal-planar coordination is rare for antimony, and the possibility of multiple bonding between antimony and chromium must be considered. Tellurium exhibits a wide range of coordination and bonding modes to manganese- and rhenium-containing fragments.
88 citations
TL;DR: The individual and combined effects of antimony and glue on zinc deposition current efficiency and polarization and on the morphology and orientation of 6h zinc deposits electrowon at 500 A m−2 and 38° C from Kidd Creek zinc electrolyte were determined as mentioned in this paper.
Abstract: The individual and combined effects of antimony and glue on zinc deposition current efficiency and polarization and on the morphology and orientation of 6h zinc deposits electrowon at 500 A m−2 and 38° C from Kidd Creek zinc electrolyte were determined. Glue increased zinc deposition polarization, reduced the deposit grain size, changed the preferred deposit orientation from basal to intermediate, but decreased the current efficiency. At concentrations above 0.02 mgl−1, antimony had a strong depolarizing effect on zinc deposition resulting in a basal deposit orientation and very low current efficiency. Certain combinations of antimony and glue, however, optimized zinc deposition current efficiency and consistently gave an intermediate 〈114〉 〈112〉 〈103〉 〈102〉 〈101〉 preferred deposit orientation. A correlation was observed between the current efficiency (CE) and the nucleation overpotential (NOP) for zinc deposition such that the CE was a maximum when the NOP of the initial cell electrolyte was 120–130 mV and when the NOP of the final cell electrolyte was 100–110 mV.
53 citations
TL;DR: In this article, pure decabromodiphenyl ether forms highly brominated PBDF in combustion at 700°C in yields of ca. 7000 ppm and the yield was significantly increased up to 16 percent in the polymeric matrix and the presence of antimony(III) oxide.
47 citations
TL;DR: In this article, a detailed qualitative classification of the lone-pair antimony chalcogenides is presented, showing that the Sb Moessbauer isomer shift increases with the covalent character of bonds.
47 citations
TL;DR: Arsenic and antimony are toxic substances in Group VA of the periodic table and their geochemistries are complicated by transformations in the environment between oxidation states and the presence of environmentally produced organometallic compounds as discussed by the authors.
45 citations
TL;DR: In this article, a 1:2, 4, 5-Tetramethyl-and pentamethylbenzene (1,2,4,5)-tetrameric tetrameric Sb4Cl12 units are crosslinked at the metal centers with four other tetramers by double-sided arene coordination (X-ray structure analysis of 1).
Abstract: 1,2,4,5-Tetramethyl-and pentamethylbenzene from stable 1:2 complexes with SbCl3 of the type (C6H6-Men) · 2SbCl3(1,2) with an inverse sandwich structure. The compounds crystallize isotypically and are isostructural to the (hexamethylbenzene)antimony and -bismuth complexes.They are thus built of tetrameric chlorine-bridged Sb4Cl12 units, which are crosslinked at the metal centers with four other tetramers by double-sided arene coordination (X-ray structure analysis of 1). The Sb atoms, which are in a distorted trigonal bipyramidal environment, show a slight deviation from a centric (η6) coordination. The same stoichiometry and the same structural principle are found for the complex (C6Me6 · 2 AsCl3 (4), which is obtained from solutions of hexamethylbenzene and AsCl3 in toluene. In 4 the arsenic atoms are η6-coordinated to the hexamethylbenzene ring from both sides (X-ray analysis). Treatment of AsBr3 with hexamethylbenzene leads to a product of the composition 5 (C6Me6) · AsBr3. Reaction of hexaethylbenzene with AsCl3 in petroleum ether leads to the formation of the 1:2 complex (C6Et6) · 2 AsCl3 (5), built of discrete inverse sandwich units, which are arranged in strings parallel to the crystallographic c axis. From solutions of AsCl3 (AsBr3), SbCl3 (SbBr3) and hexaethylbenzene in petroleum ether ternary compounds are isolated with an As:Sb ratio of 1:5.2 and 1:1.86, respectively. Single crystal X-ray structure determinations failed as a consequence of severe disorder.
44 citations
TL;DR: In this article, it has been shown that Sb 4 O 5 Cl 2 accumulates as a result of these reactions and it becomes the main direct supplier of antimony, as SbCl 3, to the gas phase.
38 citations
TL;DR: In this article, the antimony incorporation rate α(Sb) during molecular beam epitaxy (MBE) of GaAs1−ySby, AlAs 1−sby, and Al 0.5Ga0.5Sby is determined as a function of growth conditions via mass-spectrometric measurements of the nonincorporated fraction of the incident antimony flux.
Abstract: The antimony incorporation rate α(Sb) during molecular beam epitaxy (MBE) of GaAs1−ySby, AlAs1−ySby, and Al0.5Ga0.5As1−ySby is determined as a function of growth conditions via mass‐spectrometric measurements of the nonincorporated fraction of the incident antimony flux. The observed trends of an increase in Sb incorporation rate with decreasing substrate temperature and increasing group III flux, and an increase in resulting Sb content with Sb flux, are found to be in agreement with previous studies using ex situ techniques only. Additionally, the process of GaAsSb on GaAs interface formation is shown to result in a time dependent α(Sb) and is understood on the basis of a surface Sb‐content dependent Sb desorption rate. Similarly, the Sb desorption rate is found to be time dependent when an incoming Sb flux reacts with a growth interrupted GaAs surface to form a GaAsSb surface layer which is likely to be graded in composition.
TL;DR: The first example of μ,η 2 coordination of a four-electron diantimony fragment to a transition metal dimer was reported in this article, which is a tetrahedral cluster characterized by a very short SbSb bond of 2.678.
TL;DR: In this paper, the Tafel coefficient was used to determine the rate of dissolution of antimony in H 2 SO 4 solutions, and it was shown that a partially passivating oxide layer is formed on the metal surface preventing oxygen evolution.
TL;DR: In this article, a new procedure for the speciation of dissolved antimony is described, which makes use of complexation with citrate to prevent the formation of hydride from Sb(V) and allow the sele...
Abstract: A new procedure for the speciation of dissolved antimony is described. This makes use of complexation with citrate to prevent, preferentially, the formation of hydride from Sb(V) and allow the sele...
TL;DR: In this article, the optical properties of thin films of red Sb2S3 prepared by vacuum evaporation on amorphous substrates were determined from transmission measurements and the variation of the extinction coefficient, K, showed structures at energies of 4.4 and 5.4 eV.
Abstract: The optical properties of thin films of red Sb2S3 prepared by vacuum evaporation on amorphous substrates were determined from transmission measurements. The variation of the extinction coefficient,K, shows structures at energies of 4.4 and 5.4 eV. The band gap was found to be 1.7 eV for film of thickness 56 nm, and increase with thickness. The interpretation of structure was inferred from transmission electron microscopy and X-ray diffraction for thin films of antimony trisulphide. The investigated film thicknesses were from 46 to 64 nm.
TL;DR: Problemes causes par les differents degres d'oxydation des elements As, Sb, Sc doses dans un meme echantillon.
TL;DR: In this paper, the morphology, structural, optical and electrical properties of antimony tri-sulphide thin films were reported for the first time on a glass substrate by a simple chemical method using potassium antimonyl tartarate (PAT), triethanolamine (TEA), ammonia and thioacetamide (TAM).
TL;DR: In this article, the adsorption characteristics of bismuth and antimony on III-V(110) substrates have been studied as a function of overlayer coverage and deposition conditions using low energy electron diffraction (LEED).
Abstract: The adsorption characteristics of bismuth and antimony on III–V(110) substrates have been studied as a function of overlayer coverage and deposition conditions using low energy electron diffraction (LEED). We examine the different roles of chemical bonding and atomic size for determining surface ordering phenomena and epitaxy in these systems. LEED and Auger data were collected for monolayer range film thicknesses prepared on GaAs, InP, GaSb, InAs, and InSb substrates cleaved in situ. Both IV and diffraction spot profiles were measured. Our results indicate that significant differences exist between the structure and surface chemical bonding of antimony and bismuth to III–V materials which were not revealed from previous studies using GaAs alone.
Patent•
29 Aug 1990
TL;DR: In this paper, a composite plating film for sliding members, essentially containing at least one of the alloy elements selected from tin, indium, antimony, and copper; inorganic particles; and lead, was described.
Abstract: Disclosed is a composite plating film for sliding members, essentially containing at least one of the alloy elements selected from tin, indium, antimony, and copper; inorganic particles; and lead; the composition of the composite plating film being: a) at least one of the alloy elements selected from tin, indium, antimony, and copper . . . 2 to 30 weight % in total; b) inorganic particles . . . 0.3 to 25 volume %; and c) lead . . . the balance.
TL;DR: The role of temperature, hydrogen and oxygen during the atomization of the hydrides in an electrically heated quartz cuvette is discussed in this article, under certain conditions, antimony atoms form dimers or elemental antimony precipitates in the heated cuvette.
TL;DR: In this paper, new antimony sulphides have been synthesized and the crystal structure of one of them, Cs6Sb10S18·1.2H2O, has been determined to be two dimensional in nature, accommodating Cs+ ions and the Sb3+ Ione pairs in cavities within an open framework.
Abstract: New antimony sulphides have been synthesized and the crystal structure of one of these, Cs6Sb10S18·1.2H2O, has been determined to be two dimensional in nature, accommodating Cs+ ions and the Sb3+ Ione pairs in cavities within an open framework.
TL;DR: In this article, the adduct SbCl 3 ·18-crown-6·MeCN has been synthesized and its structure determined by single crystal X-ray diffraction techniques.
TL;DR: In this article, the pyrolysis of pure PA11 and PA11 flame-retarded with a decabromodiphenyl/Sb2O3 mixture was described, and the brominated fire retardant first abstracts hydrogen atoms from the polyamide chain and hydrobromic acid is formed.
TL;DR: In this article, the organic matter is destroyed by repeated attack with nitric acid and the results obtained for three different areas are compared, differences between cadmium and lead contents in vegetables are observed.
Abstract: Lead and cadmium levels in edible vegetables and antimony, lead and cadmium in drinking and raw waters from three agricultural areas exposed to different levels of environmental pollution (1-high industrial pollution, 2-high urban pollution, 3-standard low industrial and urban pollution) are determined. The organic matter is destroyed by repeated attack with nitric acid. Cadmium and lead are determined by graphite furnace atomic absorption spectrometry (GFAAS) and antimony by hydride generation atomic absorption spectrometry (HGAAS). When the results obtained for three different areas are compared, differences between cadmium and lead contents in vegetables are observed. Waters are not contaminated with antimony, cadmium or lead in any area.
TL;DR: The amorphous-polycrystalline transition accompanied by the semiconductor-metal transition, taking place in the deposited overlayer, was brought into evidence through the analysis of the energy-loss structures related to the electronic and the vibrational excitations of the system in different energy- loss regions.
Abstract: A high-resolution electron-energy-loss spectroscopy study of the Sb/({ital n}-type GaAs (110)) system grown at room temperature is presented. A very wide range of antimony coverages was exploited (from 0.02 to 200 monolayers). The amorphous-polycrystalline transition accompanied by the semiconductor-metal transition, taking place in the deposited overlayer, was brought into evidence through the analysis of the energy-loss structures related to the electronic and the vibrational excitations of the system in different energy-loss regions. In particular, the intensity change and the energy shift undergone by the substrate's Fuchs-Kliewer optical phonon, and the intensity modification of the dopant-induced free-carrier plasmon, marked a critical value for 15 monolayers coverage. The band-bending change upon antimony chemisorption has also been estimated from the plasmon-energy position, and an origin for the states inducing the Fermi-level pinning has been suggested. The evolution as a function of coverage of an electronic excitation proper of Sb, which shifts from 90 to 125 meV of loss energy, has been explained as being due to a size effect'' due to the varying overlayer thickness. This result has been obtained through the comparison of the experimental loss function with a model one. Moreover, the dielectric function of antimony has been determined in themore » 0.045--0.5-eV energy range. The high-resolution electron-energy-loss technique is also presented as a superb probe for the study of the electronic structure of narrow-band-gap surface and interface systems.« less