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31.
Huang CY He S DeGrado WF McCafferty DG Gai F 《Journal of the American Chemical Society》2002,124(43):12674-12675
This study shows that incorporation of [Rub2m-OH]2+ at the N-terminus of the Fs peptide enhances its stability by approximately 0.15 kcal/mol through the mechanism of dipole-dipole coupling at the excited state, suggesting that photoinduced charge generation at a well-controlled and specific location provides a convenient means to trigger helix-coil transition on nanosecond or even faster time scales. 相似文献
32.
G. M. Plavnik G. N. Khrustaleva G. N. Troshkin A. P. Gai 《Russian Chemical Bulletin》1990,39(5):871-874
Small-angle x-ray scattering has been used in an investigation of the pore structure of sivol, a material prepared by thermochemical treatment of chrysotile asbestos. It has been shown that sivol has a well-developed pore structure. Pore size distribution curves have been obtained, showing a maximum with a radius of gyration R=2.5–3.0 nm. The data from small-angle scattering are in good agreement with results obtained in previous calculations based on adsorption measurements (for R 2.5 nm). It has been shown that some of the finest pores are not accessible for the molecules being adsorbed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 978–981, May, 1990. 相似文献
33.
Farnan GA Fu CL Gai Z Krcmar M Baddorf AP Zhang Z Shen J 《Physical review letters》2003,91(22):226106
We report a surprising observation that the growth of the [Fe(1 ML)/Co(1 ML)](n) superlattice of L1(0) structure on Cu(100) is stable only up to six atomic layers (n=3), which cannot be rationalized by stress arguments. Instead, first-principles calculations reveal a transition from the L1(0) to the B2 structure due to the effect of dimensionality on the stability of the electronic structure of the superlattice. Whereas the majority-spin electrons are energetically insensitive to the layer thickness, the minority-spin electrons induce the transition at n=3. 相似文献
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我国计量技术规范《JJF1001—1998通用计量术语及定义》对真值、随机误差和系统误差给予了新的定义,对过去的定义作了原则上的改变.本文对新定义的科学性和合理性进行了讨论,并建议在大学物理实验教学和教材中采用. 相似文献
37.
In this paper we analyse the vibrations of an N-stepped Rayleigh bar with sections of complex geometry, supported by end lumped masses and springs. Equations of motion and boundary conditions are derived from the Hamilton’s variational principal. The solutions for tapered and exponential sections are given. Two types of orthogonality for the eigenfunctions are obtained. The analytic solution to the N-stepped Rayleigh model is constructed in terms of Green function. 相似文献
38.
Solvothermal synthesis of CdS nanowires using L-cysteine as sulfur source and their characterization
Hongde Gai Youshi Wu Lili Wu Zhigang Wang Yuanchang Shi Min Jing Ke Zou 《Applied Physics A: Materials Science & Processing》2008,91(1):69-72
An effective solvothermal reaction route has been developed for large-scale synthesis of CdS nanowires. L-cysteine was used
as both sulfur source and capping reagent. The nanowires obtained were characterized by XRD, SEM, TEM, HRTEM, UV-Vis and PL.
On the basis of time-resolved experiments, a possible growth mechanism was proposed. FTIR analysis confirmed the formation
of Cd-cysteine complex and peptide during the reaction. The mechanism was further supported by comparative experiments with
other sulfur sources.
Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users.
PACS 81.05.Bx; 81.07.-b; 81.07.BC; 81.07.Vb; 81.10.Dn 相似文献
39.
The degradation of azobenzene (AO) by a gaseous plasma is reported. The plasma was generated in a localized zone between an electrolytic solution and a tip of an anode in contact with the surface of solution by means of contact glow discharge electrolysis. There is an optimum pH for the degradation of AO. Iron (II) had a remarkable catalytic action on it. Furthermore, the degradation followed the first‐order kinetic law. Some of the intermediate products of the degradation process were detected by HPLC. 相似文献
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