Bismuth selenide iodide

BiSeI crystals obtained by a chemical‐transport reaction are orthorhombic (space group Pnma) with a = 8.6967 (17) Å, b = 4.2205 (8) Å and c = 10.574 (2) Å. It could be confimed that BiSeI crystallizes in the centrosymmetric SbSI structure type.     

On silver-thallous iodide suspensions

Summary In order to obtain general information on the colloid stability of a mixed system, silver-thallous iodide systems were preliminarily examined. In all the systems observed, the molar fractions of each metal, f_Ag and f_Tl were continuously changed by 5% so that the silver-thallous iodide systems consisted of 21 different samples. Tyndallometry was used as a simple and sufficiently accurate method for determination of colloid stability of investigated systems. For the control of the substance change in the suspensions X-ray diffraction analysis was employed. The results obtained show that at the higher percentage of silver or thallium in the systems, resulting stabilities are dependent on the stability of the main component, while in the case of equal amounts of metals two stability maxima were attained. Maxima were pointed out in discussion as the prominent points of the system.

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Zusammenfassung Um allgemeine Information über die kolloide Stabilität eines Mischsystems zu erhalten, untersuchten wir das System Silber-Thallium-Jodid. Die Molfraktionen der Metallef _Ag undf _Tl wurden kontinuierlich um 5% geändert, so daß insgesamt 21 Silber-Thallium-JodidProben untersucht wurden. Zur Bestimmung der kolloidalen Stabilität der untersuchten Systeme wurde als eine einfache und genügend genaue Methode dieTyndallometrie angewendet. Die Ag-Tl-J-Niederschläge wurden röntgenographisch untersucht. Die Ergebnisse zeigen, daß bei hohen Silberoder Thalliumgehalten die Stabilität durch die Hauptsubstanz bestimmt wird, während im Mittelbereich zwei Maxima in der Stabilität auftreten.

     

Determination of iodide with chloramine-T

A method is described for the estimation of iodide, based on its oxidation to iodate by the addition of excess of chloramine-T, destruction of the excess of chloraniine-T with dimethyl sulphoxide and determination of the iodate iodometrically. In addition, the dimethyl sulphoxide eliminates any interference from bromide or bromate.     

New route to perfluorotert-butyl iodide

Conclusions Perfluorotert-butyl iodide is formed in high yield upon pyrolysis of hexafluoropropylene with perfluoromethyl iodide. Perfluorotert-butyl iodide is also formed in low yield when perfluorotert-butyl bromide or chloroformate is treated with alkali metal iodides and also from bis(trifluoromethyl)diazirine and perfluoromethyl iodide.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 402–404, February, 1988.     

Phase transition in para-cyanoanilinium iodide

^79,81Br and ¹²⁷I NQR spectra of para-cyanoanilinium bromide, 4-CNC₆H₄NH^⊕₃ Br^?, and para-cyanoanilinium iodide, 4-CNC₆H₄NH^⊕₃I^?, respectively, have been investigated in the temperature range 77 K ? 390 K. In para-cyano-anilinium iodide a phase transition has been found to occur at 99.5 K ± 1.0 K. The transition is characterized by a sudden change in the slope ν(¹²⁷I)=f(T), and by a corresponding change in the nuclear quadrupole coupling constant. The asymmetry parameter η, which has a value of zero in the high temperature phase I, shows a small but finite increase below the transition. The nature of the phase transition in para-cyanoanilinium iodide is found to be similar to that taking place in anilinium iodide as well as in para-fluoro- and para-chloroanilinium iodide. In addition, the nuclear quadrupole coupling constant, η, and the transition temperature for para-cyanoanilinium iodide and para-chloroanilinium iodide are remarkably similar. Results for the temperature dependent studies on para-cyanoanilinium bromide are also presented.     

Very low-pressure pyrolysis. IV. The decomposition of i-propyl iodide and n-propyl iodide

The decomposition rate constant of i-PrI under conditions of very low-pressure pyrolysis (VLPP) is completely consistent with the well-known high-pressure Arrhenius parameters and the RRK(M) theory. The decomposition of n-PrI under the same conditions proceeds via two pathways, the anti-Markownikoff dehydroiodination and C? I bond scission. The data, analyzed by taking into account the mutual interaction of the two pathways, is completely consistent with the known Arrhenius parameters for the bond scission step and, when combined with a reasonable A-factor, yields an activation energy for HI elimination which is as predicted for these semi-ion pair transition states.     

Structural analysis of sulfated glycans by sequential double-permethylation using methyl iodide and deuteromethyl iodide

MALDI mass spectrometric characterization of sulfated glycans is often challenging due to their low ionization response in the positive ion mode. Here we demonstrate a new analytical approach, allowing the measurement of sulfated glycans by substituting the sulfate group with a deuteromethyl group. Sulfated glycan samples are initially permethylated before the methanolytic cleavage of their sulfate groups. Desulfated and permethylated glycans are then subjected to another permethylation step using deuteromethyl iodide to label the hydroxyl groups resulting from methanolysis. The number of attached sulfate groups is subsequently calculated from the mass-shift resulting from the chemical cleavage of these sulfate groups. The position of the sulfate substitution is then determined by collision-induced dissociation (CID) tandem mass spectrometry of permethylated and permethylated plus deuteromethylated samples. The described approach was initially optimized and validated using linear standard glycans, while its effectiveness has also been demonstrated here for the N-glycans derived from bovine thyroid-stimulating hormone (bTSH).     

Radiolysis of aqueous cesium iodide

In hypothetical accident scenarios for Light Water reactors, the extent of release of iodine upon irradiation needs to be assessed for the purpose of evaluation of the applicable source term. In this context, an understanding of the behaviour of aqueous cesium iodide solutions subjected to high gamma-ray fluxes acquires significant importance. In the present work, gamma radiolysis of a cesium iodide solution (10^–2M I^–) with and without boron additive is investigated by irradiating with⁶⁰Co source at ambient temperature. Upon irradiation of the CsI solution, iodine is liberated, and the concentration of iodide in the KOH trap present in the radiolysis vessel increases with dose. The radiolytic products I ₃ ^– , IO ₃ ^– and H₂O₂ formed in the irradiated solution are also estimated and G values obtained are reported. G(I ₃ ^– ) and G(IO ₃ ^– ) are of the order of 10^–3 and 10^–4, respectively. G(H₂O₂) decreases with increase in dose. Addition of boron up to 200 ppm, does not appear to alter significantly the release fraction of iodine.     

Clathrate hydrates of triisoamylbutylammonium iodide

The phase diagram of the (i-C₅H₁₁)₃C₄H₉NI?H₂O system is reported. Triisoamylbutylammonium iodide forms polyhydrates with hydration numbers of 36 (mp 12.5°C) and 32 (mp 13.2°C) and a dihydrate. Crystals of both polyhdrates have been isolated, and their compositions have been determined.     

Lattice dynamics of cuprous iodide

The lattice dynamics of cuprous iodide have been investigated on the basis of an ‘11-parameter’ rigid-ion model (RIM). The reported neutron scattering data of CuI are reasonably well decribed by the model, especially when an optimized procedure for the selection of parameters is used. Results are presented for the phonon dispersion curves of CuI. The critical point phonon (CPP) frequencies inferred from the model are shown to provide satisfactory assignments of the observed two-phonon features in the available Raman spectrum.