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排序方式: 共有254条查询结果,搜索用时 15 毫秒
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介绍了一种已实现工业应用的磨砂型材生产工艺。在前人研究的基础上 ,根据铝的性质 ,从碱液浓度、温度、络合、整平等方面进行试验 ,发展了砂面剂。介绍了砂面剂中部分物质的作用 相似文献
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利用金属氧化物与金属的还原反应制备了新型不锈钢 ,并研究了这种不锈钢在不同腐蚀介质中的耐蚀性能 .结果表明 ,采用这种特殊工艺制备的不锈钢具有比成分类似的变形不锈钢更优异的性能 相似文献
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在加入钼酸盐与硅酸盐复合缓蚀剂的碱性脱盐溶液中,对带锈铸铁进行脱盐缓蚀处理,对带锈铸铁处理前后的耐蚀性能进行了测试评价,并运用扫描电子显微镜和傅里叶变换红外光谱仪对锈层形貌结构进行了分析。结果表明,在该体系中脱盐缓蚀处理后,铸铁的腐蚀速度下降至5%以下,脱盐缓蚀改善了锈层结构,锈层主要组成由不稳定锈γ-FeOOH向稳定的α-FeOOH转变,锈层结合紧密,铸铁的耐蚀性能提高。 相似文献
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腐蚀钼阴极尖端溶液的配制 总被引:1,自引:1,他引:1
报导了一种配制腐蚀阴极尖端溶液的方法,用这种方法配制的溶液来腐蚀钼阴极尖端,得到了尖端曲率半径为0.1——0.6μm,这样的阴极尖端其发射特性能够满足我们用这种金属(钼)树料来制作阴极尖端的要求。 相似文献
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The bioactivity of the aqueous extracts of the leaf and stem bark of the medicinal plant, Alstonia boonei De Wild (Apocyanaceae), against the pink stalk borer, Sesamia calamistis Hampson (Lepidoptera: Noctuidae) was studied in a laboratory bioassay. The extracts were incorporated into artificial diet at a rate of 0.0% (control), 1.0%, 2.5%, 5.0%, and 10.0% (w/w). Both extracts significantly (P<0.01) reduced larval survival and weight in a dose dependent manner. The concentrations that killed 50% of the larvae (LC50) for the stem bark extract were 2.8% and 2.1% at 10 and 20 DAI (days after introduction), respectively, while those for the leaves extract were 5.6% and 3.5%. The weights of the larvae also varied significantly (P<0.05) between the treatments in a dose dependent manner. We conclude that both leaf and stem bark extracts of A. boonei are toxic, used as growth inhibitors to S. calamistis larvae, and hold good promise for use as alternative crop protectants against S. calamistis. 相似文献
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Novel distribution pattern of fibrinolytic components in rabbit tissues extract: a preliminary study
Lu XG Wu XG Xu XH Gong XB Zhou X Xu GB Zhu L Zhao XY 《Journal of Zhejiang University. Science. B》2007,8(8):570-574
Objective: The purpose of this work was to investigate the distribution pattern of fibrinolytic factors and their inhibitors in rabbit tissues. Methods: The components of the fibrinolytic system in extracts from a variety of rabbit tissues, including tissue plasminogen activator (tPA), plasminogen activator inhibitor-1 (PAI-1), plasminogen (Plg), plasmin (Pl) and α2 plasmin inhibitor (α2PI), were determined by colorimetric assay. Results: The tissue extracts in renal, small intestine, lung, brain and spleen demonstrated strong fibrinolytic function, in which high activity of tPA, Plg and Pl was manifested; whereas in skeletal muscle, tongue and stomach, higher activity of PAI-1 and α2PI showed obviously. Also excellent linear correlations were found between levels of tPA and PAI-1, Pl and α2PI, Plg and Pl. In related tissues, renal cortex and renal marrow showed distinctly higher activity of tPA and lower activity of PAI-1, with the levels of Plg and Pl in renal cortex being higher than those in renal marrow, where the α2PI level was higher than that in renal cortex. Similarly, the levels of tPA, Plg and Pl in small intestine were higher than those in large intestine, but with respect to PAI-1 and α2PI, the matter was reverse. In addition, the fibrinolytic activity in muscle tissue was lower, however, the levels of tPA, Plg, and Pl in cardiac muscle were obviously higher than those in skeletal muscles, and the levels of PAI-1 and α2PI were significantly lower than those in skeletal muscle. Conclusion: Our data demonstrate that a remarkable difference of the fibrinolytic patterns exists in rabbit tissues, which has probable profound significance in understanding the relationship between the function of haemostasis or thrombosis and the physiologic function in tissues. 相似文献
9.
李连军 《辽宁科技学院学报》2011,13(4):6-8
通过对本钢板材冷轧薄板厂镀锌卷白锈质量异议的跟踪分析,研究镀锌卷白锈的产生原因,并提出一些防止措施。并对改善企业产品质量提出一些有益的建议。 相似文献
10.
冯依锋 《襄樊职业技术学院学报》2011,10(5):22-24
国内外学者一直致力于研究钢筋与混凝土的粘结滑移本构关系,试图得到比较一致的结论,但由于钢筋与混凝土间传力机理复杂、影响因素多,目前尚无可以通用的公式。文章就普通钢筋混凝土和锈蚀后的钢筋混凝土两种情况下的粘结滑移本构关系的研究现状进行了阐述。 相似文献