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Carbonyl exchange between [MX3(13CO)]–(MX = PdCl, PtCl or PtBr) and 12CO has been studied by IR and 13C NMR spectroscopies as a function of temperature. The exchange is first-order in both CO and complex concentration, and the activation entropies are negative, suggesting an associative reaction mechanism. There is a small solvent effect, but no chloride dependence. Activation parameters and rate Carbonyl exchange between [MX(3)((CO)-C-13)](-) (MX = PdCl, PtCl or PtBr) and (CO)-C-12 has been studied by IR and C-13 NMR spectroscopies as a function of temperature. The exchange is first-order in both CO and complex concentration, and the activation entropies are negative, suggesting an associative reaction mechanism. There is a small solvent effect. but no chloride dependence. Activation para

The Transfermium Working Group (TWG) was set up in 1986 under the joint auspices of the International Union of Pure and Applied Chemistry (IUPAC) and the International Union of Pure and Applied Physics (IUPAP). Its conclusions, duly endorsed by IUPAC and IUPAP, were published in the following three reports: 1. Criteria that must be satisfied for the discovery of a new chemical element to be recognThe Transfermium Working Group (TWG) was set up in 1986 under the joint auspices of the International Union of Pure and Applied Chemistry (IUPAC) and the International Union of Pure and Applied Physics (IUPAP). Its conclusions, duly endorsed by IUPAC and IUPAP, were published in the following three reports:1. Criteria that must be satisfied for the discovery of a new chemical element to be recogni

The resource-based view explains firms’ value appropriation in buyer-supplier relationships by pointing to sustained differences in economic efficiency across firms. Firms with more efficient resources create more value than competitors, which in turn provides a “protective cushion” against price-/quality competition. However, just as firms may differ in the economic efficiency of their resources

Oxidation of SO2.nH2O/HSO3-/SO32- by Pt(CN)4Cl22- has been studied at 25-degrees-C and 1.0 M ionic strength in acidic aqueous solution by use of stopped-flow spectrophotometry. The stoichiometry of the reaction is 1:1 according to Pt(CN)4Cl22- + HSO3 + H2O --> Pt(CN)42- + 2Cl- + HSO4- + 2H+. It is first-order with respect to both [Pt(IV)] and [S(IV)]. The pH-dependence in the region 0.3 < pH < 4.5

Oxidation of dissolved sulfur dioxide, SO2·nH2O, HSO3– and SO32–, by hexaaquathallium(III) has been studied in acidic aqueous solution with ionic strength 1.0 mol dm–3 at 25 °C. The stoichiometry of the reaction has been determined: [Tl(H2O)6]3++ SO2(aq)+ 2H2O →[Tl(H2O)6]++ HSO4–+ 3H+. The kinetics has been studied by use of stopped-flow spectrophotometry under pseudo-first-order conditions with eOxidation of dissolved sulfur dioxide, SO2·nH2O, HSO3– and SO32–, by hexaaquathallium(III) has been studied in acidic aqueous solution with ionic strength 1.0 mol dm–3 at 25 °C. The stoichiometry of the reaction has been determined: [Tl(H2O)6]3++ SO2(aq)+ 2H2O →[Tl(H2O)6]++ HSO4–+ 3H+. The kinetics has been studied by use of stopped-flow spectrophotometry under pseudo-first-order conditions with e

Different methods for the synthesis of anionic dimethyl sulfide platinum complexes of the type Q[PtCl3(Me2S)] (Q = triphenylbenzylphosphonium, Ph3PBzl, or tetrabutylammonium, BU4N) and [Pt(mu-Cl)Cl(Me2S)]2 are reported. The compounds Q[PtCl3(Me2S)] were prepared by interaction of [PtCl4]2- with an excess of Me2S in non-aqueous media, reduction of [PtCl5(Me2S)]- with hydrazine sulfate, bridge-split

The kinetics for manganese-catalyzed autoxidation of sulfur(IV) (SO2.nH2O, HSO3-, SO32-) in aqueous solution has been studied spectrophotometrically at 25-degrees-C, 1 < pH < 4, [S(IV)] almost-equal-to 2.3 X 10(-5) M, 1 X 10(-6) M less-than-or-equal-to [Mn(II)] less-than-or-equal-to 1.5 X 10(-3) M, [Mn(III)] less-than-or-equal-to 4 X 10(-8) M, [O2] almost 2.5 X 10(-4) M, and low ionic strength. In

Platinum(II) complexes of the type [Pt(thioether)2Cl]+(thioether = dimethyl sulfide, thioxane) are capable of abstracting a phenyl group from the BPh4 counterion with formation of trans[Pt(thioether)2ClPh] compounds. Thermal reactions proceed both in the solid phase and in nitromethane solution at elevated temperature and have preparative importance. Phenylation of the Pt(II) centre also occurs inPlatinum(II) complexes of the type [Pt(thioether)2Cl]+(thioether = dimethyl sulfide, thioxane) are capable of abstracting a phenyl group from the BPh4 counterion with formation of trans[Pt(thioether)2ClPh] compounds. Thermal reactions proceed both in the solid phase and in nitromethane solution at elevated temperature and have preparative importance. Phenylation of the Pt(II) centre also occurs in

This study systematically evaluated the psychological reactions of a non-clinical population to the October 1989 Bay Area earthquake. Within a week of the earthquake, a checklist of anxiety and dissociative symptoms was administered to a representative sample of approximately 100 graduate students and faculty members from two different institutions in the Bay Area. A follow-up study was conducted

The impact of torture on the distribution of psychiatric disorders among refugees is unknown.We surveyed a population-based sample of 418 tortured and 392 nontortured Bhutanese refugees living in camps in Nepal. Trained interviewers assessed International Classification of Diseases, 10th Revision (ICD-10) disorders through structured diagnostic psychiatric interviews.Except for male sex, history o

A reliable and valid measure is needed for assessing the psychological symptoms experienced in the aftermath of a traumatic event. Previous research suggests that trauma victims typically experience dissociative, anxiety and other symptoms, during or shortly after a traumatic event. Although some of these symptoms may protect the trauma victim from pain, they may also lead to acute stress, posttra

This paper focuses on the on-going doctoral research of the writer. Specifically, the topic of this article is on the methodology, the theoretical approach and the first steps of the research. The general aim is the contribution of 3D documentation and the 3D digital approach to the stylistic and typological study of archaeological collections. The study is applied to the collection of the Ayia Ir

The overall kinetics for manganese(II/III) catalyzed autoxidation of dissolved sulfur dioxide has been studied by UV-vis spectrophotometry. A free-radical mechanism has been proposed, and the rate constant for one of the key reactions between manganese(II) and peroxomonosulfate has been determined by pulse radiolysis. Previous literature on manganese catalyzed autoxidation of SO2(aq) has been thor

X-Ray absorption edge and EXAFS spectra of the solvated cations of platinum(II) in water, dimethyl sulfoxide and acetonitrile and of palladium(II) in dimethyl sulfoxide have been recorded and analyzed. The cations are four-coordinated. Pt-O in Pt(H2O)4(2+) is 2.01(1) angstrom and Pt-N in Pt(CH3CN)4(2+) is 2.00(1) angstrom. The dimethyl sulfoxide solvated cations of both platinum and palladium contX-Ray absorption edge and EXAFS spectra of the solvated cations of platinum(II) in water, dimethyl sulfoxide and acetonitrile and of palladium(II) in dimethyl sulfoxide have been recorded and analyzed. The cations are four-coordinated. Pt-O in Pt(H2O)4(2+) is 2.01(1) angstrom and Pt-N in Pt(CH3CN)4(2+) is 2.00(1) angstrom. The dimethyl sulfoxide solvated cations of both platinum and palladium cont

Crystals of [Pt{(CH3)2S}4](CF3SO3)2, M(r) = 741.76, and [Pt(C4H8OS)4](CF3SO3)2.H2O, M(r) = 927.93, were prepared by dissolution of platinum(II) hydroxide in solutions of trifluoromethanesulfonic acid in dimethyl sulfide and 1,4-thioxane, respectively. The structures were determined from X-ray intensity data (Mo K-alpha, lambda = 0.7107 angstrom) collected at room temperature with a CAD-4 diffracto

Ligand exchange on square-planar Pt(1,4-dithiane)2(2+), Pd(1,4-dithiane)2(2+), and Pt(Me2S)4(2+) has been studied as a function of temperature and pressure by H-1 NMR line-broadening, isotopic labeling, and magnetization transfer experiments with deuteriated nitromethane as solvent. Second-order rate constants and activation parameters are as follows: for 1,4-dithiane exchange on Pt(1,4-dithiane)2Ligand exchange on square-planar Pt(1,4-dithiane)2(2+), Pd(1,4-dithiane)2(2+), and Pt(Me2S)4(2+) has been studied as a function of temperature and pressure by H-1 NMR line-broadening, isotopic labeling, and magnetization transfer experiments with deuteriated nitromethane as solvent. Second-order rate constants and activation parameters are as follows: for 1,4-dithiane exchange on Pt(1,4-dithiane)2

06-methylated guanine dinucleotides were used to study the influence of hydrogen bonding on the specific binding of the antitumor drug cDDP, cis-PtCl2(NH3)2, to DNA. In this interaction, the guanine-06 site appears to be important in explaining the preference for a pGpG-N7(1),N7(2) chelate, which results from H-bridge formation with the ammine ligand of cDDP. Guanine-06 methylated dinucleotides an06-methylated guanine dinucleotides were used to study the influence of hydrogen bonding on the specific binding of the antitumor drug cDDP, cis-PtCl2(NH3)2, to DNA. In this interaction, the guanine-06 site appears to be important in explaining the preference for a pGpG-N7(1),N7(2) chelate, which results from H-bridge formation with the ammine ligand of cDDP.Guanine-06 methylated dinucleotides and