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151.
王建国 《延安教育学院学报》2008,22(2)
如何提高《化工基础》的课堂教学质量,在教学中运用启发式教学不失为一种好的的方法,具体要做到:善于启疑导思,注重教知授法;"重点讲学、自学为主",用"关联感"、"发展感"、"新鲜感"来诱发学生的学习兴趣,这样才能真正把该课程的系统性、科学性与趣味性有机的结合起来,充分提高《化工基础》课的课堂教学质量。 相似文献
152.
各种化学分析仪器在考古学中的应用使考古学取得了很大的进展,本文主要从各种成分分析方法如扫描电子显微镜、X射线衍射、X射线荧光分析、金相显微镜等在青铜器及其陶范考古中的应用入手,分析了各种分析仪器在考古学中的重要作用。 相似文献
153.
154.
蔡礼儒 《乐山师范学院学报》2013,(12):35-37
文章分析了现行高中教材(人教版)化学反应速率测定实验存在的不足,从试剂、装置、实验方案等方面对实验进行了优化与改进,取得了良好效果。 相似文献
155.
Eetu-Pekka Heikkinen Juha Jaako Jukka Hiltunen 《European Journal of Engineering Education》2017,42(6):812-828
Separate approaches in engineering education, research and practice are not very useful when preparing students for working life; instead, integration of education, research and industrial practices is needed. A triangular approach (TA) as a method to accomplish this integration and as a method to provide students with integrated expertise is proposed. The results from the application of TA, both at the course and programme level, indicate that the approach is suitable for developing engineering education. The student pass rate for courses where TA has been used has been higher than for previous approaches, and the student feedback has been very positive. Although TA aims to take both theoretical and practical aspects of engineering as well as research and education into account, the approach concentrates mainly on activities and therefore leaves the goals of these activities as well as the values behind these goals uncovered. 相似文献
156.
针对实验室中SBR短程硝化反硝化工艺的硝化动力学进行研究分析.通过维持反应器内水温不变,合理控制溶解氧浓度和氨氮浓度等反应条件,并应用MATLAB编程,分析大量实验数据,求出其动力学参数,最后得到短程硝化动力学方程. 相似文献
157.
Nourbakhsh F 《Journal of Zhejiang University. Science. B》2007,8(10):725-730
The effect of vermicomposting on kinetic behavior of the products is not well recognized. An incubation study was conducted to investigate C mineralization kinetics of cow manure, sugarcane filter cake and their vermicomposts. Two different soils were treated with the four solid wastes at a rate of 0.5 g solid waste C per kg soil with three replications. Soils were incubated for 56 d. The CO2-C respired was monitored periodically and a first-order kinetic model was used to calculate the kinetic pa-rameters of C mineralization. Results indicated that the percentage of C mineralized during the incubation period ranged from 31.9% to 41.8% and 55.9% to 73.4% in the calcareous and acidic soils, respectively. The potentially mineralizable C (C0) of the treated soils was lower in the solid waste composts compared to their starting materials. Overall, it can be concluded that de-composable fraction of solid wastes has decreased due to vermicomposting. 相似文献
158.
Pakistani wheat varieties are grown over a wide agro-climatic range and as such are anticipated to exhibit yield and quality differences. It is therefore necessary to investigate the nutritional status of wheat varieties in terms of biochemical and physiochemical characteristics available for food and nutritional purposes in Pakistan. The result shows that wheat grains of different varieties contain a net protein level of 9.15%~10.27%, 2.15%~2.55% total fats, 1.72%~1.85% dietary fibers,77.65×10^-6~84.25×10^-6 of potassium and 7.70× 10 6~35.90× 10^-6 of sodium ions concentration, 0.24× 10^-6~0.84× 10^-6 of phosphorus, 1.44%~2.10% ash, 31.108~43.602 g of thousand grain mass (TGM) and 8.38%~9.67% moisture contents. This study is significant in providing an opportunity to explore the available wheat varieties and to further improve their nutritional excellence and also essential for setting nutritional regulations for domestic and export purposes. 相似文献
159.
Eleyinmi AF 《Journal of Zhejiang University. Science. B》2007,8(5):352-358
Chemical composition of Gongronema latifolium leaves was determined using standard methods. Aqueous and methanol G. latifolium extracts were tested against thirteen pathogenic bacterial isolates. Crude protein, lipid extract, ash, crude fibre and nitrogen flee extractives obtained are: 27.2%, 6.07%, 11.6%, 10.8% and 44.3% dry matter respectively. Potassium, sodium, calcium, phosphorus and cobalt contents are 332, 110, 115, 125 and 116 mg/kg respectively. Dominant essential amino acids are leucine, valine and phenylalanine. Aspartic acid, glutamic acid and glycine are 13.8%, 11,9% and 10.3% respectively of total amino acid. Saturated and unsaturated fatty acids are 50.2% and 39.4% of the oil respectively. Palmitic acid makes up 36% of the total fatty acid. Extracts show no activity against E. faecalis, Y. enterolytica, E. aerogenes, B. cereus and E. agglomerans. Methanol extracts were active against S, enteritidis, S. cholerasius ser typhimurium and P. aeruginosa (minimum inhibitory concentration (MIC) 1 mg; zone of growth inhibition 7, 6.5 and 7 mm respectively). Aqueous extracts show activity against E. coli (MIC 5 mg) and P. aeruginosa (MIC 1 mg) while methanol extracts are active against P. aeruginosa and L. monocytogenes. G. lafifolium has potential food and antibacterial uses. 相似文献
160.
The enzyme unit U, by its definition, is the amount of enzyme that catalyses the transformation of one micromole of substrate per minute under standard assay conditions. However, in practical use, it is identical with micromole or microgram per minute, which deviates from the essence of the definition as a measure of amount of substance. Such usage appears in many publications that involve enzyme kinetics and conveys obscure signification. In this article, we solved the confusion by regarding the unit U as a measure of amount of enzyme having a specified catalytic activity just like the basic SI unit mole (symbol mol) defined as the amount of substance of a system which contains as many elementary entities as there are atoms in 0.012 kg of carbon 12. We introduced the concept of unit rate, ru, which is defined as the rate of a reaction mediated by 1 U enzyme, in calculating the enzyme units in an amount of enzyme so as to avoid the inconsistence of the expression with the definition of enzyme unit. The method can also be applied to the case of katal, the recommended SI unit of enzyme activity. 相似文献