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Showing papers on "Antimony published in 1987"


Journal ArticleDOI
TL;DR: The simultaneous solubilities of the minerals pyrite, pyrrhotite, magnetite, sphalerite, galena, gold, stibnite, bismuthinite, argentite, and molybdenite have been measured in 0 to 5 m NaCl solutions from 200 degrees to 350 degrees C at CO 2 partial pressures from 0.69 to 172 bars with oxygen and sulfur fugacities controlled by the pyrites-pyr rhotite-magnetite buffer.
Abstract: The simultaneous solubilities of the minerals pyrite, pyrrhotite, magnetite, sphalerite, galena, gold, stibnite, bismuthinite, argentite, and molybdenite have been measured in 0 to 5 m NaCl solutions from 200 degrees to 350 degrees C at CO 2 partial pressures from 0.69 to 172 bars with oxygen and sulfur fugacities controlled by the pyrite-pyrrhotite-magnetite buffer. The relative solubilities follow the sequence Sb > Fe > Zn > Pb > Ag, Mo > Au, Bi in chloride-free solutions, and Fe > Sb > Zn > Pb > Au > Ag,Mo,Bi in concentrated chloride solutions. Gold solubilities as high as 5 ppm were measured in 5 m NaCl solutions. The aqueous species responsible for ore transport have been proposed based on the dependence of the solubilities on NaCl concentration and previous work on individual metal systems described in the literature. Although iron, zinc, lead, gold, and silver form chloride or hydroxy-chlo-ride complexes in 0.5 to 5.0 m NaCl solutions under these conditions, molybdenite solubility is independent of chloride concentration and stibnite solubility shows an inverse relationship to chloride content. Molybdenum is probably transported as an oxyacid and antimony as a neutral hydroxide complex. Bismuth may be chloride complexed, but the solubility of bismuthinite is so low and the results so scattered that the hydrothermal speciation of this metal remains in doubt. In the chloride-free solutions, iron is present mainly as the simple ferrous ion; zinc, antimony, and bismuth as hydroxy complexes; lead as a carbonate complex; molybdenum as molybdic acid; and gold and silver as bisulfide complexes. Mixed metal complexes appear to be unimportant under the experimental conditions. The speciation results are consistent with the Pearson hard-soft rule.

162 citations



Patent
29 Jun 1987
TL;DR: A lead free, cadmium free tin and tin/antimony based solder alloy having a wide melting range for joining copper tubes and brass pipe and fittings is presented in this paper.
Abstract: A lead free, cadmium free tin and tin/antimony based solder alloy having a wide melting range for joining copper tubes and brass pipe and fittings. The non-toxic tin based solder composition has a range of 92.5-96.9% tin, 3.0-5.0% copper, 0.1-2.0% nickel and 0.0-5.0% silver. The non-toxic tin/antimony based solder composition has a range of 87.0-92.9% tin, 4.0-6.0% antimony, 3.0-5.0% copper, 0.0-2.0% nickel and 0.0-0.5% silver and is especially suited for plumbing applications having tight loose fitting solder joints which are exposed to potable water.

64 citations


Journal ArticleDOI
TL;DR: In this paper, a theoretical approach in impurity solubility calculations for semiconductor crystals is developed and the steady-state solubilities of boron, phosphorus, arsenic, and antimony in silicon at 900 to 1200 °C are investigated and compared to the previously published values.
Abstract: A theoretical approach in impurity solubility calculations for semiconductor crystals is developed. The steady-state solubility of boron, phosphorus, arsenic, and antimony in silicon at 900 to 1200 °C is experimentally investigated and compared to the previously published values. Thermodynamic parameters related to impurity interaction in silicon matrix are derived from the correct experimental data. [Russian Text Ignored].

64 citations




Journal ArticleDOI
TL;DR: The use of stannic oxide thick films that incorporate antimony as a structural dopant for sensing combustible gases in oxidizing and fixed water vapor-containing atmospheres is described in this article.

43 citations



Journal ArticleDOI
TL;DR: In this article, the crystal structures of the methylxanthates of AsIII (two polymorphs), sbIII and BiIII are reported, and the structures are solved by normal Fourier methods and refined by a full-matrix least-squares procedure in each case on reflections which satisfied the I ≥ 2.5σ(I) criterion.
Abstract: The crystal structures of the methylxanthates of AsIII (two polymorphs), sbIII and BiIII are reported. In the monoclinic form of As(S2COCH3)3 the molecular threefold symmetry, as found in the previously reported trigonal As(S2COCH3)3, is not crystallographically imposed. The distorted octahedral environments about each of the ASIII centres is defined by three asymmetrically chelating xanthate ligands. In contrast, the sbIIIand BiIII analogues adopt different stereochemistries based on pseudo-m symmetry. In addition, the Sb (S2COCH3)3 and Bi(S2COCH3)3 molecules associate to form loosely held dimers , through weak intermolecular Me…S interactions, in their respective crystal lattices. Crystals of β-As(S2COCH3)3 are monoclinic, P21/c, with unit cell parameters a 14.816(4), b 9.641(6), c 21.255(6) A, β 90.18(2)o, Z = 8. The antimony and bismuth compounds are isomorphous, crystallizing in the triclinic space group P1, with cell dimensions (bismuth details given second) a 5.904(1), 5.924(3); b 10.4891(8), 10.499(3); c 12.3635(9), 12.485(4) A; α 95.993(6), 95.99(3); β 100.92(1), 101.76(4); γ 99.04(1), 101.45(4)o; Z = 2, 2. The structures were solved by normal Fourier methods and refined by a full-matrix least-squares procedure in each case on reflections which satisfied the I ≥2.5σ(I) criterion. Final refinement details for the β arsenic (antimony, bismuth) compounds: R 0.034 (0.027, 0.055), Rw 0.034 (0.029, 0.052) for 2777 (2115, 1894) reflections.

38 citations


Journal ArticleDOI
TL;DR: In this paper, the interference of As, Sb, Se and Sn was investigated using heated quartz tube during the hydride-generation and the atomization stages, and the results showed that the efficiency of the formation of hydrides was close to 100% in the absence of interfering elements.
Abstract: By means of the radiotracer technique supplemented by conventional absorption measurements, the interferences of As, Bi, Hg, Pb, Sb, Se, Sn and Te in amounts between 10 μg and 1 mg with the determination of As, Sb, Se and Sn by hydride generation AAS using heated quartz tube were investigated during the hydride-generation and the atomization stages Amounts up to 100 μg of Hg and Pb do not cause any detectable interference The interference of Bi and Te is dominant in the hydride-generation stage and that of As, Se, Sb and Sn in the atomization stage Tin is retained to a considerable extent in the quartz tube and the resulting memory effect makes the determination of As, Sb, and Se impossible In the absence of interfering elements, the efficiency of the formation of hydrides of As, Sb, Se and Sn was close to 100% However, a reduction of Sb(V) to Sb(III) prior to the hydride-generation is necessary for which an improved procedure was developed

36 citations


Journal ArticleDOI
TL;DR: In this paper, the binding energy of pure and antimony-doped SnO2 films has been investigated using X-ray and UV photoelectron spectroscopic studies.
Abstract: Pure and antimony-doped SnO2 films have been deposited by two different techniques: metal-organic chemical vapour deposition (MO-CVD) and spray pyrolysis of SnCl4 in the presence of air with different concentrations of antimony. X-ray and UV photoelectron spectroscopic studies have been carried out on these films and the combined data from these studies provided information about the electronic properties of antimony-doped SnO2 films and their compositions. That the binding energy of SnO is higher than that of SnO2, contrary to expectations, is because of the fact that SnO2 is more covalent than SnO. XPS has been used successfully to confirm the presence of Sb3+ and Sb5+ beyond a certain concentration of antimony (0.5 mol%) in the film, which is responsible for the decrease in conductivity and IR reflectivity. UV photoelectron spectroscopy of transparent, conducting SnO2 films has been reported for the first time. The onset of photoemission in the valence band around 2.6 eV has been explained by invoking the idea of surface states near the valence band below the Fermi level.

Journal ArticleDOI
TL;DR: In this paper, the authors proposed to determine subnanomolar levels of antimony in freshwater and seawater by cathodic stripping voltammetry preceded by adsorptive deposition of complexes with catechol.

Journal ArticleDOI
TL;DR: In this paper, the structure of rutile-related iron antimonate, FeSbO4, has been determined by electron diffraction and it is shown, in agreement with earlier studies by X-ray diffraction, that the space group is P42/mnm.
Abstract: The structure of rutile-related iron antimonate, FeSbO4, has been determined by electron diffraction. It is shown, in agreement with earlier studies by X-ray diffraction, that the space group is P42/mnm. However, and in distinct contrast to the conclusions drawn from the X-ray diffraction data and more recent neutron diffraction studies which have described the structure of the compound in terms of the random distribution of iron and antimony over the cationic sites in the oxygen octahedra, it is shown here that the iron and antimony ions are ordered such that c≈ 9.23 A as opposed to 3.07 A determined by X-ray diffraction. The extent of cationic ordering appears to be influenced by the nature of the cationic oxidation states. The means by which the structure of small,ca. 200 A diameter, particles of iron antimonate have been determined by electron-diffraction techniques is presented in detail to demonstrate the value of such methods for the structural examination of inorganic solids.


Journal ArticleDOI
TL;DR: In this paper, a gold-coated gold fiber electrode was used to determine antimony(III) and antimony (V) concentrations in the river water reference sample SLRS-1 and the seawater reference sample NASS-1 with standard deviations of 0.046 and 0.051 μg l−1, respectively.


Journal ArticleDOI
TL;DR: In this article, the antimony dithiocarbamate complexes were introduced in the Sb-S2CN moieties by hydrogen bonding from β-hydroxyl groups which was confirmed by IR, and 1H and 13C NMR spectroscopy.

Journal ArticleDOI
TL;DR: In this article, the nucleation and initial crystal growth kinetics by electrodeposition from acidic zinc solutions were studied in the absence and presence of antimony and glue on a glassy carbon electrode.
Abstract: The nucleation and initial crystal growth kinetics by electrodeposition from acidic zinc solutions was studied in the absence and presence of antimony and glue on a glassy carbon electrode. Zinc exhibits instantaneous nucleation under the experimental conditions employed in the potential region from −1600 to −2000 mV (mercurous sulphate reference). At low overpotentials antimony and glue increase the number of nuclei.


Journal ArticleDOI
TL;DR: The Geysers Geothermal field in California has been shown to be enriched with arsenic, antimony, and boron in coexisting steam as discussed by the authors, with concentrations of antimony as high as 200 μg/L. The geysers geothermal field has shown that under some circumstances elements that are transported in the vapor phase can become enriched in the liquid phase.

Journal ArticleDOI
TL;DR: The oxide of trivalent antimony is used in the glass-producing industry as a refining agent and as a glass colouring and due to the fast renal excretion of antimony, the determination of SbU is useful for biological monitoring.
Abstract: The oxide of trivalent antimony is used in the glass-producing industry as a refining agent and as a glass colouring. The batch contains up to 2% Sb2O3, a substance which has shown carcinogenic properties in animal experiments. The internal levels of antimony and lead in blood (SbB and PbB) as well as the excretion with the urine (SbU and PbU) were determined by hydrid and electrothermal atomic absorption (HY-AAS and ET-AAS), respectively. In addition, measurements of airborne Sb2O3-concentrations were performed. The 109 volunteers were employed in four different fields: melting area, batch bunker, glass-washing area, and transport/maintenance. Differences between the concentrations of antimony and lead in blood and urine with respect to the fields of activity were evaluated statistically. The highest values of airborne Sb2O3, with up to 840 micrograms/m3 (TWA), were detected in the batch bunker. Correspondingly, significantly enhanced SbU-values from 1.5 to 15.7 micrograms/l (median: 5.0 micrograms/l) were found in specimens collected from the batch mixers. In the same group, the lead excretion (PbU) with values from 9 to 110 micrograms/l (median: 43 micrograms/l) was also found to be the highest. Due to the fast renal excretion of antimony, the determination of SbU is useful for biological monitoring.

Journal ArticleDOI
TL;DR: In this article, nonstoichiometric BaTiO3 PTCR type materials are investigated with various amounts of MnO2, Sb2O3 and MgO dopants.
Abstract: Nonstoichiometric BaTiO3 PTCR type materials are investigated with various amounts of MnO2, Sb2O3 and MgO dopants. Specimens fired with a nonisothermal rate-controlled sintering profile exhibit a rather fine and uniform microstructure as compared to those processed by conventional sintering techniques. The temperature at which the resistivity anomaly begins is observed to decrease with Sb2O3 and MgO contents. The Curie point of BaTiO3-based ceramics can be altered by addition of Sb2O3, and the dielectric peak is maintained by the presence of MgO additive. Magnesium ions act as acceptors in the BaTiO2 lattice, while antimony ions as donors. The presence of magnesium compensates some of the antimony, hence the doped-BaTiO3 seminonductive region is pushed to higher contents.

Patent
09 Mar 1987
TL;DR: In this article, an aqueous sol of a crystalline tin oxide solid solution containing antimony and having a particle size not larger than 300Å is prepared by adding an alkali metal bicarbonate or ammonium biccarbonate to an acidified mixture of a compound of tin and antimony.
Abstract: An aqueous sol of a crystalline tin oxide solid solution containing antimony and having a particle size not larger than 300Å is prepared by adding an alkali metal bicarbonate or ammonium bicarbonate to an acidic aqueous solution containing a compound of tin and a compound of antimony to form a gel; purifying the gel; adding aqueous ammonia to the purified gel to form a slurry; and heating the slurry until a sol is formed.

Journal ArticleDOI
TL;DR: In this article, the authors used rotating lead-disc electrodes in sulfuric acid electrolyte containing antimony and found that antimony deposition on lead electrodes is time dependent only; at more negative potentials the deposition rate decreases with overvoltage.

Patent
27 Feb 1987
TL;DR: In this paper, a polyester resin with glass fiber, a crystallization accelerator, a flame retarder and a flame-retardant aid composed of an antimony compd and a borate was used to improve the flame retardance.
Abstract: PURPOSE:To provide the titled compsn having excellent flame retardance, strength, heat resistance, etc, and suitable for use in the production of automobile parts, by blending a polyester resin with glass fiber, a crystallization accelerator, a flame retarder and a flame-retardant aid composed of an antimony compd and a borate CONSTITUTION:100ptswt polyester resin (A) is blended with 10-80ptswt glass fiber (B), not more than 10ptswt crystallization accelerator (C) (eg, talc), 5-30ptswt flame retarder (D) (eg, tetrabromobisphenol A) and 3-15ptswt flame-retardant aid (E) composed of 1-10ptswt antimony compd (eg, antimony trioxide) and 2-12 ptswt borate (eg, zinc borate) to obtain the desired polyester resin compsn By using the antimony compd and the borate in combination as the flame-retardant aids, flame retardance can be improved without lowering the mechanical properties, etc, of the glass fiber-reinforced polyester resin

Journal ArticleDOI
TL;DR: In this paper, equilibrium segregation of antimony was measured by x-ray microanalysis in an AEM and related to boundary character and structure, and the measured apparent compositions were corrected for the relative spatial extents of the segregant layer and the excited volume.



Journal ArticleDOI
TL;DR: In this paper, the electrical conductivity of high purity tin dioxide doped with antimony was studied at temperatures of 900 to 1200°C and partial pressures of oxygen between 10−8 and 1 atm.
Abstract: The electrical conductivity of high purity tin dioxide doped with antimony was studied at temperatures of 900 to 1200° C and partial pressures of oxygen between 10−8 and 1 atm. For specimens having a dopant concentration over 1 × 1019Sb cm−3, the electrical conductivity decreased slightly with temperature and independent of oxygen partial pressure. The electrical conductivity of specimens having a dopant concentration under 1 × 10−8Sb cm−3 increased with temperature and with decreasing partial pressure of oxygen. The significance of the dopant and the thermally created defects is discussed.

Journal ArticleDOI
TL;DR: In this paper, a triclinic space group structure for the antimony compound M(S2PPh2)3 (M = Sb or Bi) was determined, and the structure was solved by Patterson and Fourier methods and refined to R 0.033 for 5 837 observed reflections.
Abstract: Crystal structures have been determined for M(S2PPh2)3(M = Sb or Bi). The antimony compound crystallises in the triclinic space group P with a= 11.321(5), b= 9.413(4), c= 17.933(6)A, α= 100.41(2), β= 97.60(2), γ= 95.80(2)°, and Z= 2; the structure has been solved by Patterson and Fourier methods and refined to R 0.033 for 5 837 observed reflections. The structure consists of isolated molecules in which the central antimony is surrounded by six sulphur atoms at the corners of a distorted pentagonal pyramid. The distance to the apical atom (2.456 A) is the shortest; the basal Sb–S distances divide into sets of two short (mean 2.595 A) and three longer (2.923–3.187 A) bonds in keeping with anisobidentate co-ordination by the dithiophosphinate groups. The bismuth analogue, Bi(S2PPh2)3, is also triclinic (P), with a= 11.909(5), b= 24.174(6), c= 15.652(5)A, α= 107.80(2), β= 92.89(2), γ= 93.11(2)°, and Z= 4; there are two independent molecules in the asymmetric unit. The structure has been solved and refined to R 0.063 for 8 779 observed reflections. Co-ordination about each independent bismuth atom is similar to that in the antimony analogue with short axial distances (2.629 A) and two short (mean 2.715 A) and three longer basal Bi–S distances (mean 2.980 A). However, the molecules dimerise through intermolecular Bi ⋯ S contacts of 3.173 and 3.301 A which are trans to the apical atoms and complete pentagonal bipyramidal co-ordination about each bismuth atom. In this case, lone-pair activity at bismuth is considered unlikely and, because of the strong structural similarities between the bismuth and antimony compounds, the antimony lone pair is also not considered to be stereochemically active.