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Dilute solutions of the square-planar tetra-aqua complex pt(H2O)42+ have been prepared in a 1.00 M perchloric acid medium by addition of excess silver(I) perchlorate to potassium tetrachloroplatinate(II), equilibration at 70°C, filtration of the silver chloride precipitate, and subsequent separation of the excess silver from the solution by electrolysis. The complex has also been prepared by additDilute solutions of the square-planar tetra-aqua complex pt(H2O)42+ have been prepared in a 1.00 M perchloric acid medium by addition of excess silver(I) perchlorate to potassium tetrachloroplatinate(II), equilibration at 70°C, filtration of the silver chloride precipitate, and subsequent separation of the excess silver from the solution by electrolysis. The complex has also been prepared by addit

The oxidative addition of iodine to Pt(CN)42− is first-order with respect to iodide, iodine and complex. The reverse reductive elimination of iodide from trans-Pt(CN)4I22- is first-order with respect to iodide and Pt(CN)4I22−. The kinetics for the reaction between bromide and trans-Pt(CN)4ClH2O2− involves a rate-determining reductive elimination of chloride, followed by a rapid oxidative addition The oxidative addition of iodine to Pt(CN)42− is first-order with respect to iodide, iodine and complex. The reverse reductive elimination of iodide from trans-Pt(CN)4I22- is first-order with respect to iodide and Pt(CN)4I22−. The kinetics for the reaction between bromide and trans-Pt(CN)4ClH2O2− involves a rate-determining reductive elimination of chloride, followed by a rapid oxidative addition

Chloride anations of PtCl5H2O−, trans-PtCl4(H2O)2 and trans-Pt(CN)4ClH2O− in the presence of PtCl42− have been studied at 50°C in 1.00M perchloric acid medium. It is shown that PtCl5H2O− is formed as the primary reaction product in the two last-mentioned anations. This is not compatible with the generally used mechanism for platinum(II)-catalyzed platinum (IV) substitutions, which gives PtCl62− asChloride anations of PtCl5H2O−, trans-PtCl4(H2O)2 and trans-Pt(CN)4ClH2O− in the presence of PtCl42− have been studied at 50°C in 1.00M perchloric acid medium. It is shown that PtCl5H2O− is formed as the primary reaction product in the two last-mentioned anations. This is not compatible with the generally used mechanism for platinum(II)-catalyzed platinum (IV) substitutions, which gives PtCl62− as

Chloride and bromide anations of PdX(H2O)3+, cis-PdX2(H2O)2 and trans-PdX2(H2O)2, acid hydrolyses of PdX3H2O−, cis-PdX2(H2O)2 and trans-PcX2(H2O)2, X = Cl, Br, have been studied at different temperatures by means of a stopped-flow technique. Rate constants and activation parameters are given. The palladium complexes react about 5×104 to 5×105 times faster than the analogous platinum(II) complexes.Chloride and bromide anations of PdX(H2O)3+, cis-PdX2(H2O)2 and trans-PdX2(H2O)2, acid hydrolyses of PdX3H2O−, cis-PdX2(H2O)2 and trans-PcX2(H2O)2, X = Cl, Br, have been studied at different temperatures by means of a stopped-flow technique. Rate constants and activation parameters are given. The palladium complexes react about 5×104 to 5×105 times faster than the analogous platinum(II) complexes.

The rate constants for the chloride and bromide anations of Pd(H2O)42+, the chloride anations of PdCl3H2O−, the bromide anation of PdBr3H2O− and the acid hydrolysis of PdCl(H2O)3+, PdBr(H2O)3+, PdCl42−, and PdBr42− have been determined at 15, 25 and 35 °C using a stopped-flow technique. The ionic strength was 1.00 M and the supporting electrolyte perchloric acid. The obtained rate constants and thThe rate constants for the chloride and bromide anations of Pd(H2O)42+, the chloride anations of PdCl3H2O−, the bromide anation of PdBr3H2O− and the acid hydrolysis of PdCl(H2O)3+, PdBr(H2O)3+, PdCl42−, and PdBr42− have been determined at 15, 25 and 35 °C using a stopped-flow technique. The ionic strength was 1.00 M and the supporting electrolyte perchloric acid. The obtained rate constants and th

Stability constants, βn, n = 1, 2, 3, 4, for the chloro and bromo complexes of palladium(II) have been calculated, using a least squares programme, from spectrophotometric measurements at 222, 234.5 and 279 nm (chloride) and at 247, 265, and 332 nm (bromide). The following values of lg(βn/M−n) were obtained: 4.47±0.01, 7.76±0.04, 10.17±0.07, and 11.54±0.09 (chloride) and 5.17±0.02, 9.42±0.04, 12.7Stability constants, βn, n = 1, 2, 3, 4, for the chloro and bromo complexes of palladium(II) have been calculated, using a least squares programme, from spectrophotometric measurements at 222, 234.5 and 279 nm (chloride) and at 247, 265, and 332 nm (bromide). The following values of lg(βn/M−n) were obtained: 4.47±0.01, 7.76±0.04, 10.17±0.07, and 11.54±0.09 (chloride) and 5.17±0.02, 9.42±0.04, 12.7

The stepwise stabililty constants, Kn for the bromo aqua complexes PtBrn−1(H2O)7−n5−n; n=4, 5, 6, formed in the successive acid hydrolyses of PtBr62−, have been determined to be K6=(.19±0.1) x 103 M−1, K5= (1.0±0.2) x 104 M−1 and K4=(1.1±0.2) x 105 M−1. A bromide assisted mechanism is proposed for the bromide anations of PtBr4(H2O)2 and PtBr5H2O-. Both these reactions are found to be first order wThe stepwise stabililty constants, Kn for the bromo aqua complexes PtBrn−1(H2O)7−n5−n; n=4, 5, 6, formed in the successive acid hydrolyses of PtBr62−, have been determined to be K6=(.19±0.1) x 103 M−1, K5= (1.0±0.2) x 104 M−1 and K4=(1.1±0.2) x 105 M−1. A bromide assisted mechanism is proposed for the bromide anations of PtBr4(H2O)2 and PtBr5H2O-. Both these reactions are found to be first order w

The Cambrian Alum Shale Formation in the Andrarum-3 core from Scania,southern Sweden, consists of black siliciclastic mudstone with minor carbonate intercalations. Four facies comprise three siliciclastic mudstones and one fine-grained carbonate. The facies reflect deposition along a transect from deep ramp to basin on a Cambrian shelf. The three mudstone facies contain abundant clay clasts and la

The ignition delay is an important quantity in low temperature combustion concepts where a prolonged ignition delay gives an enhanced fuel-air mixing process, favorable for decreased particulate and NOx emission levels. This article investigates three different low-order physics-based correlation models and their ability to predict the ignition delay for the purpose of model-based controller desig

Ever since the invention of the internal combustion engine, there has been an interest in optimizing the in-cylinder pressure to achieve reliable and efficient work output. With the use of in-cylinder pressure sensors, piezoelectric injector actuation, the possibility of multiple injection events and the increased availability of computation power, cycle-to-cycle, in-cylinder pressure optimization

The implementation of an enhanced modelling approach for fibre-reinforced composites is presented which may, in addition to the directional dependency induced by the fibres, allow the capturing of the fibre-bending stiffness. The theoretical framework is based on the introduction of higher-order gradients of the motion function as additional arguments of the energy function such that size effects

Two sets of ribosome structures have recently led to two different interpretations of what limits the accuracy of codon translation by transfer RNAs. In this review, inspired by this intermezzo at the Ribosome Club, we briefly discuss accuracy amplification by energy driven proofreading and its implementation in genetic code translation. We further discuss general ways by which the monitoring base

The Precambrian inliers of the Anti-Atlas belt across the southern part of Morocco contain numerous mafic dyke and sill swarms, which are thought to represent the erosional remnants of Proterozoic Large Igneous Provinces (LIPs). As part of an extended research campaign to date and characterize these LIPs, two amphiboles from one dyke within the Bas-Drâa inlier (western Anti-Atlas) yielded consiste

The Taghdout Group is a passive margin sequence deposited during rifting and break-up of the northern margin of the West African craton (WAC), culminating with the creation of an oceanic basin between the northern edge of the WAC and an unknown terrane. However, the age of this passive margin has been poorly constrained. It was previously thought to be c. 800–1000 Ma on the basis of age of the con

Genome-wide association studies (GWAS) have generated considerable interest in glucokinase regulatory protein (GKRP; gene name GCKR) which is an inhibitor of hepatic glucokinase (GCK), an enzyme that plays a critical role in glucose update and disposal in liver. From the initial discovery of GCKR variants associated with triglyceride and glucose levels through the identification of pleiotropic ass

Increased expression and signalling of WNT5A and interleukin-6 (IL-6) have both been shown to promote melanoma progression. Here, we investigated the proposed existence of a WNT5A-IL-6 positive feedback loop that drives melanoma migration and invasion. First, the HOPP algorithm revealed that the invasive phenotype of cultured melanoma cells was significantly correlated with increased expression of

Background and purpose — The outcome of surgical treatment of lumbar disc herniation (LDH) has been thoroughly evaluated in middle-aged patients, but less so in elderly patients. Patients and methods — With validated patient-reported outcome measures (PROMs) and using SweSpine (the national Swedish Spine Surgery Register), we analyzed the preoperative clinical status of LDH patients and the 1-year