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941.
The interaction potential of heavy ions4He,6Li,12C and16O is constructed in the folding model. The density distribution of nuclear matter for these nuclei is calculated in the framework of the hyperspherical function method. For the calculation of the folding potentials we have employed the Skyrme nucleon-nucleon forces. The influence of several effects on the results of calculations is studied: the role of the three-body forces of the nucleon-nucleon interaction, dependence of the folding potential on the mass numbers of the colliding nuclei and the possibility of observing the monopole resonance in the ion inelastic scattering. Using our folding potential as a real part of the optical potential we have calculated the differential cross section of elastic scattering of6Li from12C at laboratory energy of lithium ionsT L =90.0 MeV. Reasonable agreement with experiment is obtained.  相似文献   
942.
Platinum deposits of submicron thicknesses on polycrystalline gold substrates subjected to different thermal treatments and characterized by texture 200, 311, and 220 are characterized by methods of x-ray diffractometry and scanning electron microscopy. No deposits prepared in a potentiostatic mode exhibit a pronounced texture or a reliable correlation between a weak texture of a deposit and the substrate texture. Established is the difference of predominant directions of secondary nucleation–growth of deposit on neighboring grains of the substrate. The assumption that the deposit includes fragments the size of a few tens of micrometers with pronounced texture of different directions is substantiated.  相似文献   
943.
944.
A microwave plasma treatment in a down stream configuration was used to modify the natural hydrophobocity of untreated wool fibers. This property is a consequence of the presence of a Fatty acid monolayer (F-layer) on the outermost part of the fiber surface. The wool fibers treated with plasma were analyzed by means of X-ray photoelectron spectroscopy (XPS) without previous exposure to the air. Experiments have been carried out with air, water vapor, oxygen and nitrogen as plasma gas. The “in situ” analysis of the treated samples has permitted to differentiate between the plasma effects and those other linked to the exposure of the fibers to the air after their treatment. The results have evidenced the effects induced by the different active species generated by plasma from the different components of the air. In general, the intensity of CC peaks decreases and that of the CO, CO and OCO increases when using a gas containing oxygen species. Simultaneously, the intensity of the SS groups decreases and that of the sulphonate (SO3) increases. Other changes are also detected in the intensity of the N 1s level. The extent and characteristics of the oxidation and functionalisation of the hydrocarbon chains of the F-layer depend on the nature of gas. Thus, whereas treatments with plasmas of air and water vapor strongly affect the hydrocarbon chains of the F-layer, oxygen is less effective in the oxidation process. It has been also noted that the active species formed in the nitrogen plasma do not induce any significant change in the surface composition of the wool fibers.  相似文献   
945.
946.
云纹干涉系统及其在金瓷双材料中的应用   总被引:1,自引:0,他引:1  
利用云纹干涉法对金属烤瓷形成的双材料试件进行面内位移、应变测试,将测试结果与有限元计算结果进行了对比.结果表明:云纹干涉技术对研究具有小变形的复合材料力学行为可行、有效,结果直观,同时图像灰度变化连续,对比度高,为后续图像处理提供了较好的数据.  相似文献   
947.
A new method of purification of solution-phase combinatorial libraries has been developed. Development of a chemically inert polyaromatic anchor with a reactive "scavenger reagent" (PAHSR) allows unreacted reagents and impurities to be removed from a reaction by absorption of the PAHSR to charcoal and simple filtration.  相似文献   
948.
We obtain an approximate global stationary and axisymmetric solution of Einstein’s equations which can be considered as a simple star model: a self-gravitating perfect fluid ball with constant mass density rotating in rigid motion. Using the post-Minkowskian formalism (weak-field approximation) and considering rotation as a perturbation (slow-rotation approximation), we find second-order approximate interior and exterior (asymptotically flat) solutions to this problem in harmonic and quo-harmonic coordinates. In both cases, interior and exterior solutions are matched, in the sense of Lichnerowicz, on the surface of zero pressure to obtain a global solution. The resulting metric depends on three arbitrary constants: mass density, rotational velocity and the star radius at the non-rotation limit. The mass, angular momentum, quadrupole moment and other constants of the exterior metric are determined by these three parameters. It is easy to check that Kerr’s metric cannot be the exterior part of that metric.  相似文献   
949.
AB5型多元贮氢合金的化学制备及其性能研究   总被引:1,自引:0,他引:1  
LaNi5贮氢合金在传统的贮氢应用中得到利用而被充分的研究,但LaNi5用作电池的电极太贵,不稳定,对腐蚀太敏感,而且吸放氢过程中晶胞过度膨胀和收缩,吸放氢前后体积变化率大,从而导致合金严重粉化。为了克服这些缺点,人们采用添加辅助元素部分取代基本元素的方法。即用混  相似文献   
950.
(R)-α-取代苄胺的立体控制合成   总被引:2,自引:0,他引:2  
通过(+)-樟脑酮亚胺体系的不对称反应已有不少文献报道。近年来,我们曾先后用(+)-樟脑缩甘氨酸特丁酯和(+)-樟脑缩苄胺体系作手性模板,合成了多种生理活性的(R)-α-氨基酸,(R)-α-取代苄胺和β-氨基醇。但产物的光学收率除个别在90%以上外,多数都不高。因此,为寻找具有高的立体选择性的手性模板,我们对天然(+)-樟脑进行结构改造,按Bartlett's方法将樟脑氧化成10-樟脑酸(1),经酰氯化后,在二氯甲烷  相似文献   
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