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891.
892.
The ruthenium(II)-supported heteropolyanions [HXW7O28Ru(dmso)3]6-(X=P, 1; As, 2) are composed of a Ru(dmso)3 group attached to an unprecedented heptatungstate fragment via two Ru-O-W bonds and one Ru-O-X bond, which represents a fundamentally novel mode of Ru-coordination to a polyoxoanion framework. Multinuclear 183W, 31P, 13C, and 1H NMR studies indicate high stability of 1 and 2 in solution. 相似文献
893.
A novel catalyst for the Fenton reaction was prepared by immobilizing Fe(III) onto collagen fiber and its high activity as a catalyst for degradation of dyes under irradiation of UVC was proved. 相似文献
894.
We propose a phenomenological form of the charged lepton mass matrix which extends the idea of a ”lopsided” mass matrix found
in the literature. The features of the form are that both the 2-3 and 1-3 elements of the charged lepton mass matrix are of
order 1 and that the small elements have a new structure. This form leads to the interesting result that both large atmospheric
and solar neutrino mixing can be accounted for by the matrix. Another interesting result of this mass matrix is that it leads
to very small 1-3 mixing in the lepton sector and can suppress the branching ratio of under the present experimental limit in the supersymmetric see-saw case.
Received: 3 October 2002 / Revised version: 10 November 2002 / Published online: 24 January 2003
RID="a"
ID="a" e-mail: bixj@mail.tsinghua.edu.cn
RID="b"
ID="b" e-mail: dyb@itp.ac.cn 相似文献
895.
Long Time Propagation and Control on Scarring for Perturbed Quantized Hyperbolic Toral Automorphisms
We show that on a suitable time scale, logarithmic in
the coherent states on the two-torus, evolved under a quantized perturbed hyperbolic toral automorphism, equidistribute on
the torus. We then use this result to obtain control on the possible strong scarring of eigenstates of the perturbed automorphisms
by periodic orbits. Our main tool is an adapted Egorov theorem, valid for logarithmically long times.
Communicated by Jens Marklof
submitted 08/12/04, accepted 11/01/05 相似文献
896.
897.
898.
899.
900.
Bing ZHANG Li Juan CHEN Kai Yong GE Yah Chuan GUO Bi Xian PENG 《中国化学快报》2005,16(11):1531-1534
Multiwall carbon nanotube-supported Pt (Pt/MWNTs) catalysts with high dispersion and high loading of Pt were prepared by chemical reduction method and the loading of Pt got to 40 wt%. The average diameter of Pt nanoparticles on MWNTs was about 3.5 nm. When the hydrogen and air were used as reactant gases for PEMFC, Pt/MWNTs catalysts showed significantly higher performance than the Pt/XC-72 (carbon black) catalysts. 相似文献