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1.
Hitoshi Kurokawa Taku Nakayama Yasunori Kobayashi Ken Suzuki Mutsumi Takahashi Seiichi Takami Momoji Kubo Naotsugu Itoh Parasuraman Selvam Akira Miyamoto 《Catalysis Today》2003,82(1-4):233-240
A modified Monte Carlo (MC) simulation was performed to investigate the hydrogen absorption behavior in Pd and Pd–Ag alloys of the composition PdxAg1−x (x=0.7–0.8) under H2 pressure (0.1 MPa) at different temperatures. The present method employed can consider the dissociative adsorption of hydrogen molecule and the subsequent absorption of hydrogen atom by formalizing the relationship between the pressure of hydrogen molecule and hydrogen atom. The potential parameters were determined to reproduce the solution enthalpy of hydrogen in pure metals. The results are in good agreement with experimental findings as well as previous theoretical studies. We confirmed that our method is useful to simulate the absorption of hydrogen in metals and alloys. 相似文献
2.
Jos A. Grimbergen Koen Visscher Daniel S. Gomes De Mesquita G. J. Brakenhoff 《Yeast (Chichester, England)》1993,9(7):723-732
Individual yeast cells can be successfully isolated and recultured on plates with a new isolation method making use of optical trapping with infrared laser light. The cells can be selected on morphological criteria by high resolution microscopy. The isolation device is constructed from two coverslips separated by spacers, in which selected cells are transferred to a plastic capillary, using the optical trap. To test the procedure, selection experiments were done with a mixture of two Saccharomyces cerevisiae strains, distinguishable both in fluorescence microscopy and on agar plates. These experiments showed that only selected cells were isolated, and close to 100% of the isolated stationary-phase cells formed colonies on agar plates, indicating a high recovery. A lower recovery was obtained with exponential-phase cells, possibly because of a higher sensitivity to laser irradiation. Applications for this method may include the isolation of mutants with altered morphology and the isolation of subpopulations of yeast cultures, for their separate investigation or for the initiation of pure cultures. 相似文献
4.
席小平 《可编程控制器与工厂自动化(PLC FA)》2005,(6):132-134
本文主要介绍贺力氏Multi-Lab Hvdris定氢系统使用探讨及影响因素。 相似文献
5.
Havelock’s type of expansion theorems, for an integrable function having a single discontinuity point in the domain where it is defined, are utilized to derive analytical solutions for the radiation or scattering of oblique water waves by a fully extended porous barrier in both the cases of finite and infinite depths of water in two-layer fluid with constant densities. Also, complete analytical solutions are obtained for the boundary-value problems dealing with the generation or scattering of axi-symmetric water waves by a system of permeable and impermeable co-axial cylinders. Various results concerning the generation and reflection of the axisymmetric surface or interfacial waves are derived in terms of Bessel functions. The resonance conditions within the trapped region are obtained in various cases. Further, expansions for multipole-line-source oblique-wave potentials are derived for both the cases of finite and infinite depth depending on the existence of the source point in a two-layered fluid. 相似文献
6.
Previously unexplored resonance conditions are shown to exist for the classical hydrogen atomic system, where the electron
is treated as a classical charged point particle following the nonrelativistic Lorentz-Dirac equation of motion about a stationary
nucleus of opposite charge. For circularly polarized (CP) light directed normal to the orbit, very pronounced subharmonic
resonance behavior is shown to occur with a variety of interesting properties. In particular, only if the amplitude of the
CP light exceeds a critical value, will the resonance continue without radius and energy decay. A perturbation analysis is
carried out to illustrate the main features of the behavior. The present phenomena adds to a growing list of other nonlinear
dynamical behaviors of this simple system, that may well be important for more deeply understanding classical and quantum
connections. 相似文献
7.
8.
《Canadian Metallurgical Quarterly》2013,52(4):429-436
AbstractThis paper investigates the effects of various heat treatments on the microstructure and mechanical properties of a 1% V, 0.2 % C steel. This precipitation hardening steel was submitted to selective heat treatments, in order to produce a range of austenitic and ferritic grain sizes and structures.The limitations of high austenitizing temperatures are examined, and the heat treatment which led to good mechanical properties are discussed in relation to microstructural features. Résumé Cet article traite des effets de divers traitements thermiques sur la microstructure et les propriétés mecaniques d'un acier 1% V, 0.2 % C. Cet acier, durci par précipitation, a été soumis à divers traitements thermiques sélectifs, de manière à produire des grains de dimensions et de structures austenitique et ferrique variées.Les limitations dues à des températures élevées d'austénitisation ont été examinées, et le traitement thermique conduisant à de bonnes propriétés mécaniques sont discutés en relation avec les caractéristiques microstructurales. 相似文献
9.
李武荣 《石油化工设备技术》2011,32(6):19-21
通过对油气分离器失效部位进行宏观检查、化学成分分析、金相分析、力学性能测试、断口形貌观察及能谱分析,认为工艺介质中硫化氢浓度的上升和材料纯净度不高是导致设备失效的根本原因,并提出了相应的建议。 相似文献
10.
The electrons and holes were injected into the blend electrets of polystyrene and C60 (PS/C60) by adjusting the biases of conductive atomic force microscopy probe. We visualized the charges trapping, release, diffusion, and retention processes of the PS/C60 electrets by utilizing the Kelvin Probe Force Microscopy (KPFM), and found that the localization and retention abilities of the ambipolar charges are enhanced with the increase of C60 content, indicating that blending C60 in PS matrix is a promising method for the charge trapping layer in transistor memory devices. Furthermore, we discussed the storage and diffusion mechanisms, and speculated that the interface of C60 and PS in the blend electrets and repulsive force between charge clusters around C60 are the important factors for the novel storage effect of the blend electret. 相似文献