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41.
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Bhatt AI du Fou de Kerdaniel E Kinoshita H Livens FR May I Polovov IB Sharrad CA Volkovich VA Charnock JM Lewin RG 《Inorganic chemistry》2005,44(1):2-4
In situ EXAFS spectroscopic studies of uranium compounds in high temperature alkali chloride melts indicate the presence of oligomeric species. An investigation into UCl(3) and UCl(4) dissolved in LiCl reveals long range ordering of uranium atoms in the molten state which is not maintained on quenching. Studies of uranium dioxide dissolved in LiCl-KCl eutectic with HCl exhibit long range ordering in both molten and quenched states, and the EXAFS data can be modeled using multiple coordination shells. 相似文献
43.
Stojanovic MN Semova S Kolpashchikov D Macdonald J Morgan C Stefanovic D 《Journal of the American Chemical Society》2005,127(19):6914-6915
A complete set (YES, NOT, AND, and ANDNOT) of molecular scale logic gates based on ligase deoxyribozymes was constructed. The activity of these gates was visualized through the formation of cascades with downstream phosphodieseterase YES gates, which performed fluorogenic cleavage. 相似文献
44.
Roger W. Barnard Clint Richardson Alexander Yu. Solynin 《Proceedings of the American Mathematical Society》2005,133(7):2091-2099
For the standard class of normalized univalent functions analytic in the unit disk , we consider a problem on the minimal area of the image concentrated in any given half-plane. This question is related to a well-known problem posed by A. W. Goodman in 1949 that regards minimizing area covered by analytic univalent functions under certain geometric constraints. An interesting aspect of this problem is the unexpected behavior of the candidates for extremal functions constructed via geometric considerations.
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R. Kopp A. Argento A. C. Benvenuti D. Bollini G. Bruni T. Camporesi M. Cribier J. Cvach N. G. Fadeev J. Feltesse I. A. Golutvin M. Goossens G. Heiman D. Jamnik Y. T. Kiryushin V. S. Kisselev M. Klein V. G. Krivokhizhin V. V. Kukhtin W. Lohmann U. Meyer-Berkhout A. Milsztajn L. Monari F. L. Navarria W. D. Nowak A. Ouraou L. Piemontese P. Rich-Hennion Y. Sacquin I. A. Savin G. Smadja G. I. Smirnov A. Staude K. M. Teichert R. Tirler G. Todorova P. Todorov P. Verrecchia G. Vesztergombi M. Virchaux A. G. Volodko R. Voss J. Zacek Č. Zupančič BCDMS Collaboration 《Zeitschrift fur Physik C Particles and Fields》1985,28(2):171-174
48.
Copping R Gaunt AJ May I Sharrad CA Collison D Helliwell M Fox OD Jones CJ 《Chemical communications (Cambridge, England)》2006,(36):3788-3790
(NH4)14Na4[(Np3W4O15)(H2O)3(BiW9O33)3].62H2O (1) and (NH4)14.5Na3.5[(Np3W4O15)(H2O)3(SbW9O33)3].40.5H2O (2) each contain three neptunyl(v) moieties encapsulated within heteropolyoxotungstate frameworks in which axial {NpO2}+ oxygens form one face of a WO6 octahedron. 相似文献
49.
We describe how to use Schoenberg’s theorem for a radial kernel combined with existing bounds on the approximation error functions for Gaussian kernels to obtain a bound on the approximation error function for the radial kernel. The result is applied to the exponential kernel and Student’s kernel. To establish these results we develop a general theory regarding mixtures of kernels. We analyze the reproducing kernel Hilbert space (RKHS) of the mixture in terms of the RKHS’s of the mixture components and prove a type of Jensen inequality between the approximation error function for the mixture and the approximation error functions of the mixture components. 相似文献
50.
Dr. Mumiye A. Ogunwale Dr. Ralph J. Knipp Clint N. Evrard Prof. Lee M. Thompson Prof. Michael H. Nantz Prof. Xiao-An Fu 《Chemphyschem》2019,20(6):815-822
The click-chemistry capture of volatile aldehydes and ketones by ammonium aminooxy compounds has proven to be an efficient means of analyzing the carbonyl subset in complex mixtures, such as exhaled breath or environmental air. In this work, we examine the carbonyl condensation reaction kinetics of three aminooxy compounds with varying β-ammonium ion substitution using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). We determined the activation energies for the reactions of the aminooxy compounds ATM, ADMH and AMAH with a panel of ketones and aldehydes that included acrolein and crotonaldehyde. The measurements indicate that the activation energies for the oximation reactions are quite low, less than 75 kJ mol−1. ADMH is observed to react the fastest with the carbonyls studied. We postulate this result may be attributed to the ADMH ammonium proton effecting a Brønsted-Lowry acid-catalyzed elimination of water during the rate-determining step of oxime ether formation. A theoretical study of oxime ether formation is presented to explain the enhanced reactivity of ADMH relative to the tetraalkylammonium analog ATM. 相似文献