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991.
992.
A study of the effect of long-term alcohol consumption on the liver of well-nourished rats is described. Rats fed for 16 weeks on a semipurified diet supplemented with high levels of vitamins and lipotropic factors and alcohol corresponding to 35% of the total caloric intake developed marked fatty changes of the liver. Mild fatty changes were observed in pair-fed controls receiving as isoenergetic equivalent of sucrose instead of alcohol. Intracellular hyaline bodies, corresponding ultrastructurally to giant mitochondria were abundantly found in the hepatocytes of alcoholic rats, while in the controls they were not seen. Te findings in this investigation are postulated to provide further evidence that the long-term intake of alcohol exerts a direct causative role in the pathogenesis of liver damage.  相似文献   
993.
Using methods of mathematical statistics (cluster, dispersion, and correlation analyses), the impact strength of three types of glass containers (bottles and jars) was analyzed. Three temperature regions in which molding results in very different values of the strength of the articles are revealed. The boundaries of the molding temperature regions are critical regardless of the type of article molded and are probably only determined by the chemical composition of the glass melt. The preferred mold temperature range is 480–550°C. The results of the study are interpreted based on an analysis of the features of molding glass at different temperatures. __________ Translated from Steklo i Keramika, No. 2, pp. 3–7, February, 2007.  相似文献   
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Electroosmotic experiments have been carried out on eight different mixes of hardened cementitious matrixes including concrete, mortar and pastes, different types of binders, carbonated and non-carbonated specimens and different test conditions. From these trials, the zeta potential values have been determined and the optimum experimental parameters and devices have been established. In addition, the influence of the composition of the binder on the zeta potential has been quantified indicating that higher amounts of Al2O3 in the binder lead to higher positive values of zeta potential, while the SiO2 acts just on the opposite side. This has been explained in terms of the different i.e.p. (isoelectric point) for both oxides. Concerning the influence of carbonation, it increases the absolute value of the zeta potential toward more negative values; this behaviour has been attributed to the influence of the specifically adsorbed Ca2+ in the negative sites of the surface in the non-carbonated samples.  相似文献   
999.
Thermomechanical and chemical-ceramic properties of the PTMS basic-composition mixture for the consumable refractory lining of intermediate ladles in service at the Kombinat Magnezit Joint-Stock Co. are considered and some details of the fabrication technique are discussed. Results for the mixture tested for performance at various metallurgical plants are given. Advantages of the mixture for practical application, its microstructural characteristics in pre- and post-service conditions, and the wear behavior are discussed.  相似文献   
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