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实践教学与毕业论文同步指导模式以其特有的优势弥补传统毕业论文教学所具有的不足,扬长避短,优化教学方案,培养学生创新思维能力、调查研究能力、分析解决问题的能力,提高毕业论文质量。 相似文献
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毕业论文是培养学生运用所学知识解决实际问题,提高实践能力的重要环节,文章从毕业论文各个阶段出发,强调师生互动的作用,明确指导教师在培养学生实践创新能力所担任的重要角色。毕业论文实施过程中学生科研能力的训练,需要指导教师富于爱心、高度的责任心及言传身教的垂范。 相似文献
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本文就化学专业的本科毕业论文现状及存在问题进行了分析,并结合自己的教学经验和指导本科毕业论文的体会,有针对性地提出一些改进措施,以期提高化学专业本科毕业论文质量,为后续毕业论文的教学工作提供指导作用。 相似文献
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毕业论文(设计)是实现本科教学目标的重要环节,是本科教学教学效果的综合反映.本文分析了影响毕业论文(设计)质量的不利因素及其产生的原因,提出了提高毕业论文(设计)质量的对策和措施. 相似文献
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木脂素是由两分子苯丙素聚合而形成的一类天然化合物,广泛存在于自然界中,其中大多数木脂素为游离的状态,小部分与糖结合成苷而存在于植物的木部和树脂中,所以称之为木脂素,而最近又在动物体内发现了有别于植物木脂素的哺乳动物木脂素[1].由于大部分木脂素具有很高的抗癌、抗肝炎、杀虫等生物活性,因此被广泛的应用于在医药、农业以及日化等方面,木脂素的合成一直是有机合成中的一个热点[2],而合成木脂素的偶联条件的选择是木脂素合成中起到关键性因素,文章就几种重要木脂素的合成方法中单体的氧化偶联方式进行简单的介绍. 相似文献
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某厂焦化装置加热炉对流段结焦严重需要清焦,通过比较各种清焦技术的利弊,采用了清焦效果好、对炉管损伤小、工期短、安全环保的PIG清焦技术,清焦后加热炉运行效果良好,延长了装置的开工周期,具有很大的推广价值。 相似文献
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介绍了膜催化技术在甲烷转化反应中的应用,这些过程包括甲烷氧化偶联反应制乙烯,甲烷部分氧化制甲醇,甲烷水蒸气重整制合成气等,通过膜催化反应与传统催化反应的比较,揭示了膜催化技术的优点。 相似文献
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The effect of unsaturated groups on the crosslinking of polyethylene in the presence of chlorotrifluoroethylene (CTFE) has been studied. Butadiene- and isoprene-grafted polyethylenes with high concentrations of unsaturated groups were crosslinked more markedly than the original polyethylenes. The rate of gel formation increased with the increase in the initial concentration of unsaturated group in polyethylenes, while the rate of grafting of CTFE decreased. The concentration of unsaturated group decreased rapidly during the course of the reaction. The rate of decrease in each unsaturated group was in the order, vinylidene > vinyl >trans-vinylene. In the irradiation of polyethylene with a high concentration of unsaturated groups in CTFE, the number of grafted monomers was almost equal to the decrease in numbers of the unsaturated group. These results are discussed in relation to the reaction mechanism and the estimated activation energy of the elementary reaction 相似文献
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The influence of the parameters of curing of organosilicate coatings and the degree of completeness of interfacial chemical reactions on the total surface energy, its dispersion and polar components, and the physicochemical and protective properties of coatings is analyzed. The possibility of using organosilicate coatings as easily cleanable materials is determined by the small values of the surface energy and its polar component. 相似文献
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To determine the role of the intestinal lymphatic system in the absorption of a polycyclic aromatic hydrocarbon, 7,12-dimethylbenzanthracene,
a radiolabeled preparation of the compound was given by intraduodenal infusion to rats in doses of 10 μg, 10 mg and 20 mg
in olive oil solution. The hydrocarbon appeared to be absorbed from the intestine in a fractional manner, ca. 20% of the administered
radioactivity being recovered totally in bile and intestinal lymph in 24 hr at all three dose levels. Biliary radiolabel accounted
for 75–82% of combined recovery of radioactivity in bile and lymph with all three doses. The recovery of significant amounts
of radiolabel in bile before the appearance of isotope in lymph, together with the fact that the biliary radiolabel greatly
exceeded at all times the lymphatic recovery of isotope, suggests that an alternative pathway, presumably the portal venous
route, is of major importance in the transport of the absorbed hydrocarbon. 相似文献
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D. Schuhmann 《Electrochimica acta》1989,34(12):1889-1896
Previous recent attempts by the author for giving a more consistent physical meaning to the two-parallel-condenser model and its implications on the adsorption isotherm behaviour are reviewed. In addition, the displacement of oriented water molecules by the adsorbate is taken into account and the effects of a series capacity are discussed. This allows to consider the original expression for the charge density as a function of potential as an approximation of a model much more complex than that first treated. The new expression for the limiting capacity at maximum coverage still allows a consistent analysis from the corresponding experimental parameters. 相似文献