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941.
R. Dymarz J. L. Molina K. V. Shitikova 《Zeitschrift für Physik A Hadrons and Nuclei》1981,299(3):245-249
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.
A. N. Gavrilov L. M. Plyasova N. A. Rudina I. Yu. Molina G. A. Tsirlina T. Ya. Safonova 《Russian Journal of Electrochemistry》2004,40(9):981-986
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.
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.
950.