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241.
铅锌烧结电除尘器设计与应用 总被引:1,自引:0,他引:1
针对铅锌精矿烧结机作业特点、产生烟气条件及烟尘性质,分析、论述了电除尘器的设计,并介绍设备的调试与生产运行情况。 相似文献
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I Gromova H Biersack S Jensen OF Nielsen O Westergaard AH Andersen 《Canadian Metallurgical Quarterly》1998,37(47):16645-16652
In mammalian cells, DNA topoisomerase II is the product of two distinct genes encoding the alpha and beta isoforms of the enzyme. Besides homodimeric topoisomerase IIalpha and IIbeta, we have recently shown that alpha/beta heterodimers constitute a third population of topoisomerase II in HeLa cells. We found that topoisomerase II heterodimers are not restricted to HeLa cells but exist in different mammalian cell types, and up to 25% of the total topoisomerase IIbeta population is involved in heterodimer formation. Studies of topoisomerase II phosphorylation in HeLa cells show that heterodimers are phosphorylated in vivo to a significantly lower level compared to homodimeric alpha enzymes, but in contrast to the latter neither heterodimers nor topoisomerase IIbeta homodimers coprecipitate together with a kinase activity that is able to mediate their phosphorylation. However, both enzymes can still be phosphorylated by exogenously added casein kinase II. The differential phosphorylation of topoisomerase II heterodimers suggests an alternative regulation of this topoisomerase II subclass compared to the homodimeric topoisomerase IIalpha counterparts. 相似文献
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1引言过去十年是世界光伏快速成长的十年,中国光伏产业也快速崛起。国家非常重视这一新兴战略性产业的发展,出台的"十二五"能源规划中提到要大力发展光伏应用。作为亚洲规模最大的电源生产王国, 相似文献
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Diabetes mellitus is associated with an increased risk of premature vascular disease. Vascular research is focusing on a potential role of adhesion molecules in diabetes mellitus, since classical risk factors including hyperlipidemia and hypertension do not completely account for the increased incidence of atherosclerosis in diabetes. After the expression of adhesion molecules on the cell surface, they are shed into plasma. Thus plasma concentrations of circulating adhesion molecules may be representative for endothelial activation, damage or turnover. Recently, evidence has been accumulating that increased plasma levels of adhesion molecules may predict cardiovascular disease, may be pathognomonic for diabetic microangiopathy or may even play a functional pathophysiologic role. The purpose of this article is to briefly summarise the role of (circulating) adhesion molecules in diabetes mellitus. 相似文献
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JOURNAL OF FOOD SCIENCE 《Journal of food science》1980,45(6):1811-1814
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The compaction properties of a 1:1 acetaminophen and microcrystalline cellulose (MCC) mixture have been studied using a compaction simulator to make tablets by single compression and by a combination of precompression and main compression. The tensile strengths of the tablets and the energies involved in the compressions were determined. The tensile strengths of the tablets increased with increases in single compression pressure from 80 to 400 MPa and as the total applied pressure increased from 80 MPa up to around 400 MPa when combinations of precompression and main compression pressures were used. The tablet porosity decreased with increase in main compression pressure while the tablet tensile strengths increased. At minimum tablet porosity, further increase in main compression pressure could no longer result in increase in tablet strengths. Tablets compressed with combinations of precompression and main compression were stronger (2.15 +/- 0.02 to 3.99 +/- 0.1 MPa) than those produced with single compression (0.73 +/- 0.01 to 3.09 +/- 0.05 MPa). The total gross energies of compression increased with an increase in pressure of both the precompression and main compression. The elastic energies during main compression increased with an increase in precompression pressure as the tablet exhibited greater elastic deformation and reduced plasticity on second compression. The increase in elastic energies during main compression may also be because elastic energy is recoverable and is independent of precompression. As the precompression pressure increased, the minimum tablet porosity was attained; hence, the plastic energy during main compression became smaller while the elastic energy increased. Thus, a combination of low precompression and main compression pressures of 160/80 MPa or 80/160 MPa are more advantageous in the tableting of the 1:1 acetaminophen:MCC than a high single compression pressure of 320 or 400 MPa. 相似文献