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Transition Metal Ions in Atmospheric Waters. 4.1 Metal Ion Catalyzed Autoxidation of Dissolved Sulfur Dioxide

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

Structures of Solvated Cations of Palladium(II) and Platinum(II) in Dimethyl Sulfoxide, Acetonitrile and Aqueous Solution Studied by EXAFS and LAXS

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

cis-Influence and trans-Influence on Bond Distances. Synthesis and Crystal Structures of the Bis(trifluoromethanesulfonates) of Tetrakis(dimethylsulfide)- and Tetrakis(1,4-thioxane)-platinum(II)

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

Proton NMR Kinetic Study of Ligand Exchange on Bis(1,4-dithiane)platinum(II), Bis(1,4-dithiane)palladium(II) and Tetrakis(dimethylsulfide)platinum(II) : High Presssure NMR Kinetics 51

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

Guanine-O6 Methylation Reduces the Reactivity of D(GpG) towards Platinum Complexes

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

trans influence on bond distances. Structures of trans-diiodobis(tetrahydrothiophene)palladium(II) and trans-diiodobis(tetrahydrothiophene)platinum(II)

Crystals of trans-diiodobis(tetrahydrothiophene)-palladium(II) and trans-diiodobis(tetrahydrothiophene)platinum(II) were prepared by dissolving the appropriate metal iodide in tetrahydrothiophene at 353 K and cooling to room temperature. Crystal data at room temperature (Mo K-alpha, lambda = 0.7107-angstrom) are: [PdI2(C4H8S)2], M(r) = 536.54, triclinic, P1BAR, a = 8.4920 (8), b = 8.8248 (1), c =

Solvent Exchange and Complex Formation Reactions of Pd(II) in Aqueous Solution. Mechanistic Information from High Pressure Studies

High pressure NMR and stopped-flow techniques have been employed to study a series of water exchange and complex formation reactions of Pd(II) outlined in (1) and (2). The volumes of activation show an interesting correlation with the partial molar volume of the entering ligand and underline the operation of an associative substitution mechanism in all cases.High pressure NMR and stopped-flow techniques have been employed to study a series of water exchange and complex formation reactions of Pd(II) outlined in (1) and (2). The volumes of activation show an interesting correlation with the partial molar volume of the entering ligand and underline the operation of an associative substitution mechanism in all cases.

Rank Reduction with Convex Constraints

This thesis addresses problems which require low-rank solutions under convex constraints. In particular, the focus lies on model reduction of positive systems, as well as finite dimensional optimization problems that are convex, apart from a low-rank constraint. Traditional model reduction techniques try to minimize the error between the original and the reduced system. Typically, the resulting re

Polarity dependent strongly inhomogeneous In-incorporation in GaN nanocolumns

In this work, GaN/InGaN/GaN nanocolumns (NCs) have been grown by molecular beam epitaxy. Selective area growth (SAG) and self-organized growth (SOG) were performed simultaneously in patterned and unpatterned regions of the same substrate, respectively. The resulting structures show different tip morphologies and structural properties due to the different polarity along the growth direction, namely

Combinatorial Knowledge Bases : An Integrative and Dynamic Approach to Innovation Studies

The aims of this article are (1) to critically review the theoretical arguments and contribution of the knowledge base approach to economic geography and innovation studies, and the value added and limitations of applying it in empirical studies as reported about in the extant literatures; (2) to propose a new interpretation of the knowledge base approach by integrating it into a larger analytical

Fluorescence correlation spectroscopy in thin films at reflecting substrates as a means to study nanoscale structure and dynamics at soft-matter interfaces

Structure and dynamics at soft-matter interfaces play an important role in nature and technical applications. Optical single-molecule investigations are noninvasive and capable to reveal heterogeneities at the nanoscale. In this work we develop an autocorrelation function (ACF) approach to retrieve tracer diffusion parameters obtained from fluorescence correlation spectroscopy (FCS) experiments in

Effect of Oligomerization of Counterions on Water Activity in Aqueous Cationic Surfactant Systems

A sorption calorimetry study of cationic cetyltrimethyl ammonium surfactants with four different counterions was performed. The counterions were acetate, succinate, citrate, and butyl tetracarboxylate with formal charges ranging from 1 to 4, respectively. The counterions with 2-4 charges can be considered as oligomers. In all the cases, hydration experiments started with dry solid phases that upon

Oscillator strengths for high-excitation Ti II from laboratory measurements and calculations

This work reports new experimental radiative lifetimes of six 3d2(3F)5s levels in singly ionized titanium, with an energy around 63 000 cm-1 and four 3d2(3F)4p odd parity levels where we confirm previous investigations. Combining the new 5s lifetimes with branching fractions measured previously by Pickering et al., we report 57 experimental log gf values for transitions from the 5s levels. The lif

Nuclear magnetic relaxation by the dipolar EMOR mechanism : Three-spin systems

In aqueous systems with immobilized macromolecules, including biological tissue, the longitudinal spin relaxation of water protons is primarily induced by exchange-mediated orientational randomization (EMOR) of intra- and intermolecular magnetic dipole-dipole couplings. Starting from the stochastic Liouville equation, we have developed a non-perturbative theory that can describe relaxation by the

Ordkonst och levnadskonst : Det skrivande subjektet i John Ashberys, Yves Bonnefoys och Inger Christensens diktning

The chief aim of this thesis is to investigate the use of language called poetry during the second half of the 20th century and how the writing subject is implicated in it. Building on the theoretical perspectives enabled by Michel Foucault’s late work on the technologies of the self, I analyze the practices of writing in John Ashbery’s, Inger Christensen’s and Yves Bonnefoy’s poetry. The introduc

Perceptual and acoustic differences between authentic and acted nonverbal emotional vocalizations

Most research on nonverbal emotional vocalizations is based on actor portrayals, but how similar are they to the vocalizations produced spontaneously in everyday life? Perceptual and acoustic differences have been discovered between spontaneous and volitional laughs, but little is known about other emotions. We compared 362 acted vocalizations from seven corpora with 427 authentic vocalizations us

3.6 A 60pJ/b 300Mb/s 128×8 Massive MIMO precoder-detector in 28nm FD-SOI

Further exploitation of the spatial domain, as in Massive MIMO (MaMi) systems, is imperative to meet future communication requirements [1]. Up-scaling of conventional 4×4 small-scale MIMO implementations to MaMi is prohibitive in-terms of flexibility, as well as area and power cost. This work discloses a 1.1mm2 128×8 MaMi baseband chip, achieving up to 12dB array and 2× spatial multiplexing gains.

Design and Analysis of the Medium-β Elliptical Cavities for the European Spallation Source Accelerator

This thesis is dedicated to the design and analysis of superconductingelliptical cavities. Elliptical cavities play a central role in modern particle ac-celerators due to their high efficiency. After an introduction to the EuropeanSpallation Source project, the thesis goes through the design of the medium-βcavity. The RF design of the inner cell and end cell are presented in sequencein paper I . T

ESS Elliptical Cavities and Cryomodules

The accelerator of the European Spallation Source (ESS) is a 5 MW proton linac to be built in Lund Sweden. Its superconducting section is composed of 3 cavity families: double spoke resonators, medium beta and high beta elliptical multi-cell cavities. This paper presents the electromagnetic and mechanical design of the elliptical cavities. Both elliptical families are housed in 4-cavity cryomodule