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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

Modelica allows systems to be described with reuseable components and with a high precision. To be able to use such complex models efficiently, high demands are set on tools that allow the user to extract the information needed from the models in a straight-forward manner. For this purpose, design-of-experiments techniques can be used to systematically analyze the complex models.In this paper, it

Background: High-density Lipoprotein (HDL) attenuates endothelial cell apoptosis induced by different cell-death stimuli such as oxidation or growth factor deprivation. HDL is the main plasma carrier of the bioactive lipid sphingosine 1-phosphate (S1P), which it is a signaling molecule that promotes cell survival in response to several apoptotic stimuli. In HDL, S1P is bound to Apolipoprotein M (A

Pepper spray (OC) is a policing tool aimed to prevent or stop aggressive behavior by quickly and temporarily incapacitate without injuring. To date, few studies have investigated OC’s operational usefulness and limitations. OC reduced violent behavior in 93% of the 936 incidents investigated. However, the operative range was often <2 m and it took between 3 and 5 s of spraying before obtaining eff

Control applications contain both logic, sequencing, and control algorithms. A holistic view of this is seldom presented in teaching and papers. One reason is the separation of communities -- automation groups typically come from the Programmable Logic Controller (PLC) world while control engineers primarily come from the Distributed Control System (DCS) world. Both logic, sequencing, and control

Objective: To assess the complete vascular risk factor (VRF) profile of idiopathic normal pressure hydrocephalus (INPH) using a large sample of representative patients with INPH and population-based controls to determine the extent to which vascular disease influences INPH pathophysiology. Methods: All patients with INPH who underwent shunting in Sweden in 2008-2010 were compared to age- and sex-m

Quantum mechanical weak values of projection operators have been used to answer which-way questions, e.g. to trace which arms in a multiple Mach–Zehnder setup a particle may have traversed from a given initial to a prescribed final state. I show that this procedure might lead to logical inconsistencies in the sense that different methods used to answer composite questions, like “Has the particle t