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961.
B. Hannoyer A. A. M. Prince M. Jean R. S. Liu G. X. Wang 《Hyperfine Interactions》2006,167(1-3):767-772
Crystalline LiFePO4 has been synthesized using solid-state, spray pyrolysis, and wet chemical methods. The crystal parameters were obtained from Rietveld’s refinement methods of the X-ray diffraction patterns. A detailed investigation of the Fe valency carried out using Mössbauer spectroscopy at room temperature indicates that Fe is predominantly present in its bivalent state. 相似文献
962.
Alignment carbon nanotubes (ACNTs) were synthesized on silicon substrate coated with Ni catalyst film and Ta buffer layer by plasma-enhanced hot filament chemical vapor deposition using CH4, NH3, and H2 as the reaction gas, and they were investigated by scanning electron microscopy and transmission electron microscopy. It is found that the diameter of the bamboo-structured ACNTs is increased from 62 to 177 nm when the substrate temperature was changed from 626 to 756 °C. Their growth rate is enhanced by the substrate temperature in a range of 626-683 °C and it is reversely reduced with the substrate temperature after the substrate temperature is over 683 °C. Beginning with wetting phenomenon, the effects of the substrate temperature on the structure and growth rate of the ACNTs are analyzed. 相似文献
963.
An enantioselective Michael addition of malonate to nitroalkenes is efficiently catalyzed by low loading demethylquinine salts in water; the yield range from 49% to 93% and the ee up to 90%. 相似文献
964.
Least-squares finite difference (LSFD) method, one of mesh-free methods, is used to solve slider air bearings problem through discritizing the generalized Reynolds equation into nonlinear systems of algebraic equations. Two approximation schemes for the linearization of these equations are presented and compared. And, some new techniques to search supporting points for the reference node in the mesh-free method were proposed and explored. Therefore, these improvements eliminate some potential limitation of the LSFD method previously published and further facilitate its employment in complex slider models. Advanced step slider as an example of negative pressure sliders is simulated and verified using the improved LSFD mesh-free method in head disk systems. 相似文献
965.
Wensheng Wang 《Annales de l'Institut Henri Poincaré (B) Probabilités et Statistiques》2007,43(5):619-631
The almost sure sample function behavior of the vector-valued fractional Brownian sheet is investigated. In particular, the global and the local moduli of continuity of the sample functions are studied. These results give precise information about the continuity and the oscillation behavior of the sample functions. 相似文献
966.
967.
Using the Ward-Takahashi identity, on-shell condition, bound Dirac equation and off-shell expansion, a reduced version of half off-shell virtual photon nucleon vertex has been suggested. The vertex are decomposed into several different order terms: the on-shell terms, first and second off-shell terms. The off-shell behaviour of the form factors is discussed in the one meson loop model. Using the reduced vertex and parametrized off-shell form factors the quasielastic response functions are calculated for several nuclei at ¦q¦–kf and for56Fe at large ¦q¦ up to 1.14 GeV/c and at ?q2=0.9 (GeV/c)2. The Coulomb sums are evaluated and a comparison of the theoretical prediction with data is given. The off-shell electron nucleon cross section is calculated and compared with the “cc1” off-shell extrapolation. 相似文献
968.
本文利用^1HNMR,UV-Vis方法,研究了t-BuNO二聚体在有机溶剂及水溶液中的裂解反应产物,分析了其反应的动力学,提出了在非极性的有机相中t-BuNO二聚体为均裂反应,而在极性的水相中为均裂和异裂同时进行的竞争反应。 相似文献
969.
Angular momentum effect in prescission particle multiplicities for a light system by diffusion model
W. Ye W. Q. Shen Z. D. Lu J. Feng Y. G. Ma J. S. Wang K. Yuasa-Nakagawa T. Nakagawa 《Zeitschrift für Physik A Hadrons and Nuclei》1997,359(4):385-389
The effect of angular momentum on the competition between fission and particle emission during light system fission process was studied via fission diffusion model. The prescission particle multiplicities were found to increase with decreasing angular momentum. The experimental prescission proton and α particle multiplicities can be fitted for 10.6 MeV/nucleon 84Kr(27Al,binary fission) reaction with this model. Entrance channel effect found in [1] is proved to be angular momentum effect. 相似文献
970.
OntheEquationn=p+k~2inShortIntervals¥WangTianze(DepartmentofMathematics,HenanUniversity,Kaifeng475001)Abstract:DenotebyE(X,Y)?.. 相似文献