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Showing papers on "Iodide published in 1982"


Patent
10 Nov 1982
TL;DR: In this paper, a tabular grain silver halide emulsion is disclosed comprised of a dispersing medium and silver bromoiodide grains having a thickness less than 0.3 micron and a diameter of at least 0.6 micron.
Abstract: HIGH ASPECT RATIO SILVER BROMOIODIDE EMULSIONS AND PROCESSES FOR THEIR PREPARATION Abstract of the Disclosure A tabular grain silver halide emulsion is disclosed comprised of a dispersing medium and silver bromoiodide grains. Tabular silver bromoiodide grains having a thickness less than 0.3 micron and a diameter of at least 0.6 micron have an average aspect ratio of greater than 8:1 and account for at least 50 percent of the total projected area of the silver bromoiodide grains. The high aspect ratio silver bromoiodide grains are prepared by concurrently running silver, bromide, and iodide salts into a reaction vessel while controlling pBr. Prior to the concurrent addition of silver and iodide salts the reaction vessel is substantially free of iodide.

114 citations




Journal ArticleDOI
TL;DR: Aqueous sols of TiO2 (anatase, particle radius 25 A) were excited with (347.1 nm)-laser light and the reaction of valence-band holes with halide ions (X = I−, Br−, Cl−) was investigated as discussed by the authors.
Abstract: Aqueous sols of TiO2 (anatase, particle radius 25 A) were excited with (347.1 nm)-laser light and the reaction of valence-band holes with halide ions (X = I−, Br−, Cl−) was investigated. Hole transfer takes place within the duration of the (10 ns)-laser pulse and results in the formation of anion radicals according to the sequence: The quantum yield of X increases in the order Cl < Br < I, attaining 0.8 for I at pH 1. It is affected by pH, halide concentration and the presence of a protective agent for the sol. RuO2 deposited onto TiO2 enhances markedly Cl and Br -formation, but has no effect on the yield of I. Laser-photolysis investigation of halide oxidation were also carried out with colloidal Fe2O3 (particle radius 600 A). For I2−formation, the quantum yield exceeds 0.9 indicating almost quantitative hole scavenging by iodide.

97 citations


Journal ArticleDOI
TL;DR: In this paper, free radical addition of an F-alkyl iodide (RFI) to an alkenol or ester, followed by appropriate reduction is an efficient method for preparing the corresponding Falkyl-alkanols of the homologous series, RF(CH2)n−OH.

92 citations


Journal ArticleDOI
TL;DR: In this paper, a metal-polyyne polymers consisting of conjugated acetylenic systems, where PD and R represent the Pd(PBu3)2-moiety and alkyl groups, respectively, were prepared by polycondensation between palladium chlorides and α,ω-diethynyl compounds in amines using a catalytic amount of cuprous iodide.
Abstract: Metal-polyyne polymers consisting of palladium and conjugated acetylenic systems, where PD and R represent the —Pd(PBu3)2—moiety and alkyl groups, respectively, were prepared by polycondensation between palladium chlorides and α,ω-diethynyl compounds in amines using a catalytic amount of cuprous iodide. The molecular weights of the polymers formed were greatly affected by the basicity of the amines and the addition of free phosphines to the polymerization system. Under the optimum conditions, i.e., in the presence of CuI and PBu3 (in molar ratio 1/4) in piperidine at room temperature, polymer Ia (R1 = R2 = H) having Mw = 29,000 was obtained.

76 citations


Journal ArticleDOI
TL;DR: In this article, the reactions of perfluoroalkyl iodides with allyl, vinyl or aryl halides with ultrasonically dispersed zinc in the presence of palladium catalyst are described.
Abstract: The reactions of perfluoroalkyl iodides with allyl, vinyl or aryl halides with ultrasonically dispersed zinc in the presence of palladium catalyst proceeded smoothly to give the corresponding allyl...

73 citations


Journal ArticleDOI
TL;DR: In this article, a new cationic, water soluble phosphine (2-diphenylphosphinoethyl)trimethylammonium iodide, Ph 2 PCH 2 CH 2 NMe + 3 I −, (amphos iodide) has been synthesized and characterized.

69 citations


Patent
30 Sep 1982
TL;DR: In this paper, a process for preparing radiation-sensitive tabular grain silver bromoiodide emulsions is described, which is achieved by providing in a reaction vessel an emulsion comprising a dispersing medium and high iodide silver halide grains.
Abstract: A process is disclosed of preparing radiation-sensitive tabular grain silver bromoiodide emulsions. This is achieved by providing in a reaction vessel an emulsion comprising a dispersing medium and high iodide silver halide grains. The mean diameter of the silver halide grains is less than 0.1 micron, and the concentration of iodide is less than 10-2 mole per liter of the emulsion. Upon concurrently running into the reaction vessel silver and bromide, a high aspect ratio tabular grain silver bromoiodide emulsion is obtained.

67 citations



Journal ArticleDOI
TL;DR: It is reported here that the microbicidal activity of the myeloperoxidase-H2O-chloride system on Escherichia coli is associated with the loss of iron into the medium as measured by the release of 59Fe from prelabeled organisms.

Patent
30 Sep 1982
TL;DR: In this article, a double-jet precipitation process is described for photo-graphic emulsions containing tabular silver chloride grains which are substantially internally free of bromide and iodide.
Abstract: A double-jet precipitation process is disclosed for preparing radiation-sensitive photo- graphic emulsions containing tabular silver chloride grains which are substantially internally free of bromide and iodide. In forming the emulsions chloride and silver salt solutions are concurrently run into a dispersing medium while controlling both pH and pAg. Tabular grains having an average aspect ratio of greater than 8:1 are obtained.

Journal ArticleDOI
J.G. Eales1, J.P. Chang1, G. van der Kraak1, R.J. Omeljaniuk1, L. Uin1 
TL;DR: In this paper, the thyroid radioiodide uptake was increased at higher temperatures, implying elevated thyroidal secretion of T 4 into the blood and increased thyroidal status at higher temperature.

Journal ArticleDOI
TL;DR: It is proposed that Fe2+ and H2O2 (Fenton's reagent) generate OH X (or a closely related substance), which interacts with iodide to form one or more toxic species.
Abstract: A potent antimicrobial system is described which consists of ferrous sulfate (Fe2+), hydrogen peroxide (H2O2), and iodide in 0.02 M sodium acetate buffer pH 5.5. H2O2 could be replaced by the H2O2-generating system glucose + glucose oxidase. This system, unlike the myeloperoxidase-H2O2-halide system, was ineffective when iodide was replaced by bromide, chloride, or thyroxine, and was inhibited by EDTA, the hydroxyl radical scavengers mannitol and ethanol, and phosphate and lactate buffers at the same concentration and pH as the acetate buffer used. The acetate buffer, however, could be replaced by water. It is proposed that Fe2+ and H2O2 (Fenton's reagent) generate OH X (or a closely related substance), which interacts with iodide to form one or more toxic species.


Journal ArticleDOI
TL;DR: The dependence of the chloride distribution coefficient on the co-ion of solutions of different alkali fluorides up to 11M is tested on the strongly basic anion-exchange resin AG1-X10 as mentioned in this paper.
Abstract: The dependence of the chloride distribution coefficient on the co-ion of solutions of different alkali fluorides, MF, up to 11M is tested on the strongly basic anion-exchange resin AG1-X10. Under the same experimental conditions the distribution coefficient decreases in the following order for M+: Na+>K+>Rb+>Cs+. This can be explained by the different co-ion-chloride interactions. The consequence of this interaction for a chromatographic separation of chloride is shown with 5M KF and CsF solutions, used as eluants. Depending on the fluoride concentration, the distribution coefficient passes through a minimum value to increase again at higher electrolyte concentration. The non-exchange electrolyte in the resin phase is responsible for this effect. In addition, the bromide and the iodide distribution coefficients up to 10M KF solutions are determined. One results is that the selectivity coefficient between halide ions increases at higher electrolyte concentrations.

Journal ArticleDOI
TL;DR: In this paper, the reactions of these silver-phosphine-halide complexes with anhydrous stannous halides are investigated and the structures of the isolated complexes, both in the solid state and in solution, are discussed in terms of their 31 P NMR and 119m Sn Mossbauer spectra and their molar conductivities.

Journal ArticleDOI
TL;DR: In this paper, allylic phenylthioethers are converted in one step to homoally-phenylthyroides by treatment with methylene iodide or ethylidene iodides in the presence of diethylzinc but not zinc-copper or zinc-silver couples.

Patent
20 Dec 1982
TL;DR: In this article, the authors described the process for the preparation of these emulsions, photographic elements incorporating them, and the processes for the use of the photographic elements for the extraction of photographic elements.
Abstract: Silver halide emulsions of limited iodide content, processes for the preparation of these emulsions, photographic elements incorporating these emulsions, and processes for the use of the photographic elements are disclosed. In the emulsions silver halide grains predominantly bounded by {111} crystal faces and containing insufficient iodide to direct silver salt epitaxy to selected surface sites of the grains are present. Silver salt is epitaxially located on and substantially confined to selected surface sites of the silver halide grains, this being accomplished by the use of an adsorbed site director.

Journal ArticleDOI
TL;DR: Samarium di-iodide selectively cleaves the 2-chloroethyl carbamate (1), and fragments the 11α-steroidal xanthate (3), where other reducing reagents fail as mentioned in this paper.
Abstract: Samarium di-iodide selectively cleaves the 2-chloroethyl carbamate (1), and fragments the 11α-steroidal xanthate (3), where other reducing reagents fail.

Journal ArticleDOI
TL;DR: In this article, the cobalt-catalyzed hydrocarbonylation of methanol into acetaldehyde is discussed and the nature of the iodide promoter has a decisive influence on the reaction rate, the covalent CH3I being much more active than the ionic LI, KI, MePBu3I.

Journal ArticleDOI
TL;DR: Polymethyliodobenzenes react with sodium trifluoroacetate, in tine presence of copper(I) iodide, in hexamethylphosphoric triamide at 150-180°C, giving a mixture of the corresponding polymethylbenzotrifluoride, parent hydrocarbon, and bis(polymethylphenyl) ether as discussed by the authors.
Abstract: Polymethyliodobenzenes react with sodium trifluoroacetate, in tine presence of copper(I) iodide, in hexamethylphosphoric triamide at 150–180°C, giving a mixture of the corresponding polymethylbenzotrifluoride, parent hydrocarbon, and bis(polymethylphenyl) ether.


Journal ArticleDOI
TL;DR: Benzeneselenenenyl iodide (BEI) is a good reagent for the formation of carbocyclic compounds from diolefins as mentioned in this paper.
Abstract: ‘Benzeneselenenyl iodide’, prepared in situ by the reaction of diphenyl diselenide and iodine, is a good reagent for the formation of carbocyclic compounds from diolefins.

Journal ArticleDOI
TL;DR: In the case of cyclopentadienylMo(cyclooctenyl)(NO)I as discussed by the authors, the enantiomers were separated via spontaneous resolution through crystallization of the complex in the space group P 2 1 2 1 1 2 2 1.


Journal ArticleDOI
TL;DR: In this paper, it was shown that Ag + within the iodide polyhedra is not the unique current carrier and that a wide distribution of barrier heights exists in these glasses.

Journal ArticleDOI
TL;DR: In this article, thermal analysis and spectral and magnetic measurements of the Ni(H2O)2(AA)2]X2·nH 2O complexes in a solid phase were investigated.
Abstract: Thermal reactions of the [Ni(H2O)2(AA)2]X2·nH2O complexes in a solid phase were investigated, where AA is N,N′-diethylethylenediamine (NN′-deen), N,N-dimethylethylenediamine (NN-dmen), or N,N′-dimethylethylenediamine (NN′-dmen), and where X− is Cl−, Br−, I−, NO3− or ClO4−. By means of thermal analyses and spectral and magnetic measurements in a series of these complexes before and after heating, the following results were obtained. In the case of the NN′-deen complexes, only the perchlorate deaquates to change from octahedral to square-planar, but the other salts, such as the chloride, bromide, iodide, and nitrate, undergo deaquation-anation keeping their octahedral configuration. The deaquation-anation was also observed in the chloride, bromide, and nitrate of the NN-dmen complexes, but the iodide deaquated, and so was transformed from octahedral to square-planar. In the NN′-dmen complexes, only deaquation-anation was detected, irrespective of the anions (Cl−, Br−, I−, and NO3−). The effects of N-substit...

Journal ArticleDOI
TL;DR: In this paper, the reaction of perfluoroalkyl iodides with terminal alkynes and ultrasonically dispersed zinc in the presence of copper(I) iodide has been described.
Abstract: The reaction of perfluoroalkyl iodides with terminal alkynes and ultrasonically dispersed zinc in the presence of copper(I) iodide proceeded smoothly to give the corresponding vinyl perfluoroalkylides in good yields.

Journal ArticleDOI
01 Jan 1982-Analyst
TL;DR: In this paper, a method for the determination of between 0 and 5 µg l-1 of total iodine and iodate-iodine present in natural freshwaters is described. But this method is based on the catalytic effect that iodide has on the reaction between ammonium cerium(IV) sulphate and arsenic(III) oxide.
Abstract: Procedures for the determination of between 0 and 5 µg l–1 of total iodine and iodate-iodine present in natural freshwaters are described. Total iodine is determined using the catalytic effect that iodide has on the reaction between ammonium cerium(IV) sulphate and arsenic(III) oxide. An earlier method has been modified rigorously and according to Mark's (1973) recommendations. The analysis of sets of eleven replicate samples showed that the total iodine concentration could be resolved to within ±0.1 µg l–1(±2 × standard error) at the 95% confidence level. The iodate-iodine in the sample is determined by the same procedure after any iodide-iodine has been extracted into chloroform as an ion pair with the tetraphenylarsonium cation. The optimisation of the extraction procedure is described. The analysis of sets of six replicate samples encompassing the 0 to 5.0 µg l–1 range of iodate-iodine concentrations and containing also 1.0 µg l–1 of iodide-iodine returned essentially the same standard errors as for total iodine determination. The effect upon the methods of various substances that could be present in freshwaters is described together with tests conducted upon some organic iodine compounds. The latter experiments suggest that the unsuspected presence of organic iodine compounds in natural waters would be problematic. Analysis for total iodine can be conducted at the rate of approximately 50 samples per hour and that for iodate-iodine at about 20 per hour.