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71.
72.
Zusammenfassung Röntgenamorphe mechanische Gemenge oder Gemeinschaftsfällungen von Beryllium-Chrom(III)-Mischhydroxiden zeigen ein unterschiedliches Verhalten im H2O2-Zerfall, dessen Geschwindigkeit einer Reaktion I. Ordnung entspricht.
X-ray amorphous mechanical mixtures and co-precipitations of mixed beryllium-chromium(III) hydroxides show activities differing in the rate of decomposition of H2O2, which corresponds to a first order reaction.相似文献
73.
Alfons Krause 《Monatshefte für Chemie / Chemical Monthly》1965,96(4):1132-1133
Ohne Zusammenfassung 相似文献
74.
Alfons Krause Irena Plura L. Ŀomozik 《Monatshefte für Chemie / Chemical Monthly》1965,96(5):1581-1585
Zusammenfassung Basisches Magnesiumcarbonat und basisches Zinkcarbonat erlangen nach Tieftemperaturbehandlung mit flüssiger Luft eine bedeutend größere Oberfläche, die auch bei den betr. oxidischen Abkömmlingen nach ihrer thermischen Beanspruchung bei 800° bestehen bleibt. Ebenfalls tieftemperatur-empfindlich ist das dunkelbraune röntgenamorphe Eisen(III)-hydroxid (Orthohydroxid), während das topochemische röntgenamorphe und ziegelfarbige Eisen(III)-hydroxid (Iso-Orthohydroxid) sowie ein daraus gewonnenes hellgelbes -FeOOH, die schon von sich aus oberflächengroß sind, sich in dieser Hinsicht als indifferent erwiesen. Die aus den verschiedenen Eisen(III)-hydroxiden bei 800° gewonnenen -Oxide hatten eine sehr differente scheinbare Dichte bzw. Oberfläche. 相似文献
75.
Excitation functions of the analyzing power in elastic proton-proton scattering from 0.45 to 2.5 GeV
M. Altmeier F. Bauer J. Bisplinghoff K. Büßer M. Busch T. Colberg L. Demirörs H. P. Engelhardt P. D. Eversheim K. O. Eyser O. Felden R. Gebel M. Glende J. Greiff F. Hinterberger E. Jonas H. Krause T. Lindemann J. Lindlein B. Lorentz R. Maier R. Maschuw A. Meinerzhagen D. Prasuhn H. Rohdjeß D. Rosendaal P. von Rossen N. Schirm V. Schwarz W. Scobel H. -J. Trelle K. Ulbrich E. Weise A. Wellinghausen R. Ziegler 《The European Physical Journal A - Hadrons and Nuclei》2005,23(2):351-364
Excitation functions AN(plab,c.m.) of the analyzing power in elastic proton-proton scattering have been measured in an internal target experiment at the Cooler Synchrotron COSY with an unpolarized proton beam and a polarized atomic hydrogen target. Data were taken continuously during the acceleration and deceleration for proton kinetic energies Tlab (momenta plab) between 0.45 and 2.5 GeV (1.0 and 3.3 GeV/c) and scattering angles 30 ° c.m. 90°. The results provide excitation functions and angular distributions of high precision and internal consistency. The data can be used as calibration standard between 0.45 and 2.5 GeV. They have significant impact on phase shift solutions, in particular on the spin triplet phase shifts between 1.0 and 1.8 GeV. 相似文献
76.
Ortiz W Krueger BP Kleiman VD Krause JL Roitberg AE 《The journal of physical chemistry. B》2005,109(23):11512-11519
We present a theoretical investigation of energy transfer in the phenylene ethynelene dendrimer known as the nanostar. Data from extensive molecular dynamics simulations are used to model the dynamical effects caused by torsional motion of the phenyl groups. We compare rate constants for energy transfer between the two-ring chromophore and the three-ring chromophore obtained via the F?rster model, the ideal dipole approximation (IDA), and the transition density cube (TDC) method, which has as its limit an exact representation of the Coulombic coupling. We find that the rate constants obtained with the TDC are extremely sensitive to the phenyl group rotation, whereas the constants computed with the F?rster model and the IDA are not. The implications of these results for the interpretation of recent pump-probe experiments on the nanostar are discussed in detail. Finally, we predict the temperature dependence of the rate constant for energy transfer. 相似文献
77.
Heidenreich BJ Elliott OT Charney ND Virgien KA Bridges AW McKeon MA Peck SK Krause D Gordon JE Hunter LR Lamoreaux SK 《Physical review letters》2005,95(25):253004
A new method for the detection of the electron electric dipole moment (EDM) using a solid is described. The method involves the measurement of a voltage induced across the solid by the alignment of the sample's magnetic dipoles in an applied magnetic field, H. A first application of the method to GdIG has resulted in a limit on the electron EDM of 5 x 10(-24)e cm, which is a factor of 40 below the limit obtained from the only previous solid-state EDM experiment. The result is limited by the imperfect discrimination of an unexpectedly large voltage that is even upon the reversal of the sample magnetization. 相似文献
78.
Industrial methods for the production of optically active intermediates 总被引:15,自引:0,他引:15
Breuer M Ditrich K Habicher T Hauer B Kesseler M Stürmer R Zelinski T 《Angewandte Chemie (International ed. in English)》2004,43(7):788-824
Enantiomerically pure amino acids, amino alcohols, amines, alcohols, and epoxides play an increasingly important role as intermediates in the pharmaceutical industry and agrochemistry, where both a high degree of purity and large quantities of the compounds are required. The chemical industry has primarily relied upon established chemical methods for the synthesis of these intermediates, but is now turning more and more to enzymatic and biotechnological fermentation processes. For the industrial implementation of many transformations alternative methods are available. The advantages of the individual methods will be discussed herein and exemplified by syntheses of relevant compounds. 相似文献
79.
Long-duration experiments with clouds of microparticles are planned for the ICAPS facility on board the International Space Station ISS. The scientific objectives of such experiments are widespread and are ranging from the simulation of aerosol behaviour in Earths atmosphere to the formation of planets in the early solar system. It is, however, even under microgravity conditions, impossible to sustain a cloud of free-floating, microscopic particles for an extended period of time, due to thermal diffusion and due to unavoidable external accelerations. Therefore, a trap for dust clouds is required which prevents the diffusion of the particles, which provides a source of relative velocities between the dust grains and which can also concentrate the dust to higher number densities that are otherwise not achievable. We are planning to use the photophoretic effect for such a particle trap. First short-duration microgravity experiments on the photophoretic motion of microscopic particles show that such an optical particle-cloud trap is feasible. First tests of a two-dimensional trap were performed in the Bremen drop tower. 相似文献
80.
This article describes the identification of the autophosphorylation sites of the G protein-sensitive class I phosphoinositide 3-kinase isoforms beta and gamma by mass spectrometry. Since discrimination and suppression effects prevented the immediate detection and sequencing of phosphopeptides in complex mixtures, a strategy was applied that involved (32)P-radiolabeling of the phosphoproteins, cleavage of the phosphoproteins with several proteases and/or cyanogen bromide, separation of the resulting peptide mixtures by micro-reversed-phase liquid chromatography, and mass spectrometric analysis of fractions containing phosphopeptides. As a result the primary autophosphorylation sites of phosphoinositide 3-kinase p110beta and p110gamma subunits could be unambiguously assigned to the C-terminal Ser 1070 and Ser 1101, respectively. 相似文献