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41.
Protection of Metals and Physical Chemistry of Surfaces - The distribution of the density of the adsorbate inside the transition region of the liquid–vapor interface in a slit pore, in which...  相似文献   
42.
Protection of Metals and Physical Chemistry of Surfaces - The effect of adsorption on the characteristics of equilibrium rough surfaces of vapor–liquid and vapor–solid interfaces at a...  相似文献   
43.
The effect of technological parameters on the properties of 2-and 42-day film-forming solutions of the system CuO-TiO2 is analyzed. It is found that the initial components have a strong effect on the maturing of film-forming colloidal solutions (FCS) and the properties of coatings. The properties of coatings obtained from solutions of different age are associated with changes in their microstructure. The index of refraction and the thickness of the films from 42-day FCS are essentially independent of the calcination regime; the variation of the refractive coefficient and chemical stability is inconsistent.  相似文献   
44.
Thymocyte infection with HIV-1 is associated with thymic involution and impaired thymopoiesis, particularly in pediatric patients. To define mechanisms of thymocyte infection, we examined human thymocytes for expression and function of CXCR4 and CCR5, the major cell entry coreceptors for T cell line-tropic (T-tropic) and macrophage-tropic (M-tropic) strains of HIV-1, respectively. CXCR4 was detected on the surface of all thymocytes. CXCR4 expression on mature, high level TCR thymocytes was similar to that on peripheral blood T cells, but was much lower than that on immature thymocytes, including CD34+ thymic progenitors. Consistent with this, stroma-derived factor-1 (SDF-1) induced calcium flux primarily in immature thymocytes, with CD34+ progenitors giving the strongest response. In addition, SDF-1 mRNA was detected in thymic-derived stromal cells, and SDF-1 induced chemotaxis of thymocytes, suggesting that CXCR4 may play a role in thymocyte migration. Infection of immature thymocytes by the T-tropic HIV-1 strain LAI was 10-fold more efficient than that in mature thymocytes, consistent with their relative CXCR4 surface expression. Anti-CXCR4 antiserum or SDF-1 blocked fusion of thymocytes with cells expressing the LAI envelope. In contrast to CXCR4, CCR5 was detected at low levels on thymocytes, and CCR5 agonists did not induce calcium flux or chemotaxis in thymocytes. However, CD4+ mature thymocytes were productively infected with the CCR5-tropic strain Ba-L, and this infection was specifically inhibited with the CCR5 agonist, macrophage inflammatory protein-1beta. Our data provide strong evidence that CXCR4 and CCR5 function as coreceptors for HIV-1 infection of human thymocytes.  相似文献   
45.
Ninefold drawing of pearlitic steel wire is investigated. On the basis of multiscale computer models, the behavior of pearlite colonies at the surface of the wire and in its central layer is analyzed. The key factors are the orientation of the cementite lamellae relative to the drawing axis, the interlamellae distance, and the shape of the cementite inclusions. On the basis of finite-element models, the laws governing the reorientation of the pearlite colonies, change in shape and size of the cementite lamellae, and localization of the deformation in the ferrite are determined. The model results are verified by means of metallographic results and industrial experiments.  相似文献   
46.
Experimental values of oxygen thermal conductivity are presented for the temperature interval 300–1000°K at a pressure of 105 Pa.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 49, No. 1, pp. 94–97, July, 1985.  相似文献   
47.
The results of the studies of the effect of the ASUD99 grade nanodiamonds additions on physico-mechanical properties of the drilling tool metal matrix have been discussed. The optimal concentration of nanodiamond powder additives in the composition of a hard alloy mixture has been defined. The addition of 1–2 wt % nanodispersed diamonds has been shown to contribute to binding oxygen in the thermooxidation of diamond in the course of the tool manufacture, which makes it possible to reduce the amount of pores in the matrix material structure and to increase its density by 1.7% and hardness by 24.3%.  相似文献   
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