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1.
Sand spots, attached to a copper ball surface by means of polyvinyl acetate adhesive and distributed over the surface with areal density that ranges between one spot per 1.18 cm2 (for low‐density spots) and one spot per 0.51 cm2 (for high‐density spots), serve as a temporary heat transfer enhancer during the quenching in liquid nitrogen. Highest heat flux densities, achieved during quenching, lie in the range 10.8 to 20.2 W/cm2, depending on the sand layer structure. Application of the temporary enhancer increases an amount of heat, evacuated by highly effective nucleate and transition boiling, by factor of 4.5 as compared with the bare sample. The process of sand layer preparation, data acquisition peculiarities, relationship between heat exchange efficiency and the spots areal density, along with sand grit size are discussed in this paper.  相似文献   
2.
Powder aluminum-phosphorus master alloys for modifying hypereutectic silumins are developed. Optimal treatment modes of powder mixtures in a high-energy planetary mill which give minimal losses of the starting material and the microstructure with the uniform and dispersed distribution of particles of excess phases in the aluminum matrix are selected. The phase composition of formed master alloys is investigated by electron probe microanalysis. The high efficiency of modifying the hypereutectic silumin Al-17 wt % Si by introducing phosphorus (0.008 wt %) using fabricated master alloys is shown.  相似文献   
3.
In atherosclerosis; blood low-density lipoproteins (LDL) are subjected to multiple enzymatic and non-enzymatic modifications that increase their atherogenicity and induce immunogenicity. Modified LDL are capable of inducing vascular inflammation through activation of innate immunity; thus, contributing to the progression of atherogenesis. The immunogenicity of modified LDL results in induction of self-antibodies specific to a certain type of modified LDL. The antibodies react with modified LDL forming circulating immune complexes. Circulating immune complexes exhibit prominent immunomodulatory properties that influence atherosclerotic inflammation. Compared to freely circulating modified LDL; modified LDL associated with the immune complexes have a more robust atherogenic and proinflammatory potential. Various lipid components of the immune complexes may serve not only as diagnostic but also as essential predictive markers of cardiovascular events in atherosclerosis. Accumulating evidence indicates that LDL-containing immune complexes can also serve as biomarker for macrovascular disease in type 1 diabetes.  相似文献   
4.
The possibility of determining the hot cracking index using the calculated value of the effective solidification range is investigated for multicomponent cast aluminium alloys based on the system Al–Si–Cu–Mg with Mn, Ni, Fe and Zn additives. The upper limit of the effective solidification range was calculated as the temperature of formation of 65 wt-% solid phase using Sheil model. The linear relationship of the hot cracking index and the effective solidification range in the industrial and experimental multicomponent alloys based on the Al–Si–Cu–Mg system is demonstrated.  相似文献   
5.
In experiences on rats is shown, that 22 daily upkeeping of animals on a diet including eritrit in a dose 1 g/weight of a body, do not cause any changes from the party intestinal microflora and morphological structure of internal bodies. However, the specified doze eritrit causes statistically authentic increase of levels conditionally-pathogenic anaerobius of the representatives microflora, first of all staphylococcus and citratessimilation enterobacteria.  相似文献   
6.
One month keeping of rats on a diet with 23% fat extracted from a polar shark liver, causes not sharply pronounced fatty infiltration of liver, a moderate hyperplasia of spleen lymphoid tissue as well as its plasmatization and an increase of megakaryocytes, the predecessors of thrombocyte cells, in it.  相似文献   
7.
This paper reviews evidence for the immune-enhancing effect of Spirulina (Sp) and Selen-Spirulina (Se-Sp) in male Wistar rats. The rats of control group fed half-synthetic diet. Rats of experimental groups consumed the half-synthetic diets with Sp (10 g/kg diet) or Se-Sp (350 microg Se/kg diet) for 2 weeks. Using rats lymphocytes in vitro after phytohemagglutinin stimulation was demonstrated that lymphocytes from Sp and Se-Sp groups secreted of interleukin-2 and interferon-gamma more control group. Induction of interleukin-4 was comparable with once of control group. We believed that Sp and Se-Sp are more effective in stimulating a Th-1--type response and hence potentiates cell-mediated immunity. The immunostimulatory effect of Sp and Se-Sp was confirmed by morphologic and morphometric investigation of rats spleen, also with by NBT-test of peritoneal macrophages.  相似文献   
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Separation of glyoxylic acid from unpurified multicomponent technological mixtures, resulting in the process of direct oxidation of glyoxal, and preparation of sodium glyoxylate are developed. The mixtures are treated with an optimal amount of CaCO3, which has to be prespecified by acidic–basic titration of the technological mixtures. Both separation of glyoxylic acid and preparation of sodium glyoxylate take place owing to ionic exchange reactions: calcium glyoxylate is easily converted into glyoxylic acid by action of oxalic acid. Reaction with Na2CO3 leads to the formation of sodium glyoxylate.  相似文献   
10.
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