Showing papers on "Antimony published in 1973"

Molecular Basis of Flame Inhibition.

Abstract: The role played by inorganic chemical additives in fire retardancy and flame inhibition is considered. Particular attention is given to the molecular level aspects of commercially important systems containing compounds of antimony, halogens, and phosphorus. The flame inhibiting function of metal containing additives is also discussed.

Sub Microgram Determination of Arsenic, Selenium, Antimony and Bismuth By Atomic Absorption Utilizing Sodium Borohydride Reduction

Abstract: A rapid and sensitive method for the determination of arsenic, selenium, antimony and bismuth is described. These elements and their compounds are reduced to the corresponding hydride with sodium borohydride. The gaseous hydride is generated and collected by means of a generator fitted with a collapsible reservoir. The collected gases are subsequently introduced into an argon supported hydrogen flame and determined utilizing atomic absorption.

Flameless Atomic Absorption Determination of Volatile Hydrides Using Cold Trap Collection

Abstract: The hydrides of arsenic, antimony, bismuth, and selenium are collected in a liquid nitrogen cold trap and then volatilized into either an argon-entrained air-hydrogen flame or into a Perkin-Elmer HGA-2000 Graphite Furnace for atomic absorption measurement. Flameless atomization results in approximately ten-fold lower detection limits. The sensitivities and detection limits in nanograms are, respectively, 1.0 and 0.2 for arsenic, 5.6 and 1 for antimony, 2.0 and 1 for bismuth, and 40 and 10 for selenium.

Stability of dilute standard solutions of antimony, arsenic, iron and rhenium used in colorimetry

Abstract: A study has been made of the stability of dilute standard solutions of antimony (4 µg ml–1), arsenic (20 µg ml–1), iron (50 µg ml–1) and rhenium (5 µg ml–1) used in colorimetry. The standard elements in these solutions were determined over a period of 2 months by using colorimetric procedures developed in this laboratory and reported previously. Tests were carried out on standard solutions stored in soda-glass, in borosilicate glass and in rigid polyethylene containers.The dilute standard antimony solutions, prepared either by dissolving antimony potassium tartrate in water, or by dissolving elemental antimony in sulphuric acid and diluting the solution with water, were found to be stable (i.e., to deteriorate by less than 2 per cent.) over a period of 50 days. Similar dilute standard antimony solutions containing hydrochloric acid deteriorated rapidly, however.The dilute standard arsenic solutions prepared either by dissolving arsenic(III) oxide in sodium hydroxide solution and then neutralising the solution with hydrochloric acid, or by dissolving disodium hydrogen arsenate heptahydrate in water, were found to be stable. Arsenic(III) in the former standard solution was oxidised slowly by dissolved oxygen, but the total arsenic present in the solution remained unchanged and could be determined by the molybdenum-blue method.An iron(III) standard solution, 0·06 M in hydrochloric acid and prepared from ammonium iron(III) sulphate, was stable for at least 2 months, as was a standard potassium perrhenate solution in a buffer solution of pH 6.Light in the laboratory and the material of the containers did not adversely affect the solutions reported to be stable. Light accelerated the deterioration of the antimony solutions that contained hydrochloric acid, and the material of the containers had a slight effect on the rate of deterioration.

A critical study of Brilliant green as a spectrophotometric reagent: extraction of chloro-complexes of antimony, thallium, gallium and indium, and of tetrabromoindate(III), and improved procedures for the determination of antimony and thallium

Abstract: Use of cerium(IV), instead of nitrite, to oxidise antimony(III) improves the procedure for the determination of antimony with Brilliant green. Antimony(III) is oxidised in 6 M hydrochloric acid solution, the excess of oxidant being reduced with hydroxylammonium chloride. Brilliant green hexachloroantimonate(V) is extracted from 2 M hydrochloric acid solution with two 10-ml portions of toluene, the Brilliant green reagent solution being added to the aqueous solution immediately before each extraction. When a pure sample of dye is used, and the extraction is made rapidly after the addition of Brilliant green, complete recovery of antimony is effected. The recommended procedure is precise and reliable.A similar procedure based on the extraction of tetrachlorothallate(III) ions gives complete recoveries of thallium and is an improvement on existing procedures. Tetrachlorogallate(III) and tetrachloroindate(III) ions are not completely extracted by toluene, and procedures based on such extractions cannot be recommended.

An Automated Method for the Determination of Arsenic and Antimony

Abstract: An automated method for determining arsenic and antimony by atomic absorption spectrophotometry based on the evolution of the corresponding hydride by sodium borohydride is reported. This method is rapid and sensitive, and is most suitable for the routine monitoring of the arsenic and antimony levels in surface and ground water, as well as in polluted water.

The Preparation and Properties of Complexes of Antimony and Bismuth Trifluorides with Strong Fluoride Acceptors

Abstract: The reactions of antimony and bismuth trifluorides with the pentafluorides of antimony and arsenic in liquid sulfur dioxide yield the adducts SbF3•SbF5 (type A), SbF3•AsF5, BiF3•3SbF5, and BiF3•AsF...

Mössbauer spectroscopy of 121Sb in adduct complexes of antimony pentachloride

Abstract: The Mossbauer spectra of Sb121 in a variety of oxygen and nitrogen adduct complexes of antimony pentachloride (SbCl5L where L = NCCH3, NCC(CH3)3, NCCl, NCCCl3, OPCl3, OP(Ph)3, DMF, DMSO, NO2CH3, ON(CH3)3, Cl−, Br−) are reported. The experimental data are analyzed using the transmission integral. This technique is shown to be essential in order to get reliable hyperfine interaction parameters. Under these conditions the quadrupole interactions deduced from the Mossbauer spectra are in perfect agreement with those measured by NQR spectroscopy. The dependence of the quadrupole interaction and isomer shift on the donor power of the adduct ligand is explained in terms of the variation of the number of electrons transferred between the antimony atom and the six surrounding ligands and is supported by the NQR data available on the chlorine ions.

Oxidation/ammoxidation catalyst

Abstract: An oxidation/ammoxidation catalyst contains the elements antimony, uranium, iron, bismuth, and molybdenum, and optionally, nickel and/or cobalt, in a catalytic active oxidized state.

Antimony in the Lead‐Acid Battery

Abstract: It is well known that antimony, which is alloyed in the grids of the lead-acid battery to improve their castability, corrosion resistance, and strength, affects the properties of the battery in various ways. Of particular interest is its apparent beneficial effect on the cycle life of the positive plate. It has been suggested that antimony is responsible for maintaining a minimum concentration of ..cap alpha..PbO/sub 2/ during cycling, which in turn stabilizes the plate structure. If this is so, the function of antimony may be to nucleate new ..cap alpha..PbO/sub 2/ crystals during charge or to passivate already existing ..cap alpha..PbO/sub 2/ during discharge. In an effort to shed further light on this proposed mechanism the author studied the crystal structures of ..cap alpha.. and ..beta.. PbO/sub 2/ and certain Ab/sub 2/O/sub 6/ compounds to which they are related. More specifically, he determined if the compound PbSb/sub 2/O/sub 6/ could reasonably be expected to grow expitaxially onto ..cap alpha..PbO/sub 2/ (or vice versa) and passivate (or nucleate) it. 4 references.

Vinyl halide stabilizer compositions of antimony organic sulfur-containing compounds and metal carboxylates

Abstract: A vinyl halide resin stabilizer composition which essentially contains: A. AN ANTIMONY ORGANIC SULFUR-CONTAINING COMPOUND, FOR EXAMPLE, ANTIMONY ALKYL MERCAPTIDES, ANTIMONY MERCAPTOACID ESTERS AND THE LIKE, AND B. AN ALKALI OR ALKALINE EARTH METAL SALT OF AN ORGANIC ACID, SUCH AS Group I or Group II-a Periodic Table metal salts of carboxylic acids. These compositions synergistically contribute to the long term heat stability of vinyl halide resin compositions and offer significant heat stabilization economies. Efficiencies of the antimony organic compounds are improved in the compositions disclosed thereby permitting the reduction in amounts of such compounds needed for stabilization, and the inhibition of stabilizer exudate from the stabilized resin.

Localized Impurity States in Liquid Metals; Electrical Resistivity of Dilute 3d-Transition Metals in Liquid Antimony

Abstract: The electrical resistivities of dilute 3 d -transition metals in liquid antimony are measured. The resistivity changes by 1 at % of 3 d -transition metals, Δ ρ, are small magnitude within \(\pm 2{\mu}\varOmega\) cm. These small changes are mainly attributed to the d -resonant scattering. The t -matrix formulation based on Ziman theory is used for the estimation of Δ ρ in which we ignored the all η's contribution other than η 2 since the d -resonance seems to be dominant compared with other scatterings. Some discrepancies between experimental results and calculated values are found, while both changes have a same tendency.