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功能意念和交际能力是七十年代末英语教学的新概念。本文回顾了英语教学的发展历史及方法;探讨了功能意念的内容及作用;讨论了交际能力的内涵,揭示了现代英语教学的方向和培养的目标。 相似文献
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In order to carry out decolorization, sludge protein solution, a dark brown close to black solution from activated sludge, was subjected to 60Co γ-ray irradiation in the presence of hydrogen peroxide. UV/Vis spectrophotometric method was used to investigate the effect of H2O2 on the coloration apparent kinetics and rate constants of sludge protein solution under γ-ray irradiation. In addition, the effects of irradiation dose, initial sludge protein solution concentration, and pH value on the decolorization efficiency of sludge protein solution were studied. Results showed that the decolorization apparent kinetics of sludge protein solution was a first-order reaction. The solution decolorization percentage increased with the increase of irradiation dose or the decrease of initial sludge protein solution concentration. The examination results of pH value showed that the sludge protein solution could be more efficiently decolorized in alkaline media than in acid media. Moreover, sensory evaluation and foamability analysis indicated that irradiated samples under H2O2 oxidation showed better sensory score and foamability. 相似文献
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张卫江 《渭南师范学院学报》1995,(1)
社会文化背景知识传输需要教学者逐渐地渗入到实际中去，更需要外语学习者日积月累的功夫和敏锐的观察与思考的能力。只有这样，才能使外语学习者知其语言内涵，明其事理。 相似文献
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张卫江 《渭南师范学院学报》1992,(1)
本文首先介绍了交际语言教学的形成和发展的过程,简述了几位著名语言学家的理论对它的影响;其次探讨了交际语言教学的语言理论,即语言是交际的工具,语言教学的目的是开发学习者的交际能力;最后,讨论了交际语言教学的学习理论以及交际语言教学在我国外语教学中的重要地位和意义。 相似文献
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A large amount of residue including benzoic acid, benzyl benzoate and fluorenone can form in the production of benzoic acid
by oxidizing toluene. To recycle the resources and reduce secondary pollution, the treatment of benzoic acid residue was carried
out to obtain the three purified materials by flash-vacuum distillation combination method, and the influence of the operating
parameters, such as the top pressure, reflux ratio and top and bottom temperatures was investigated to obtain the best operating
conditions. The experimental results show that the benzoic acid purity can reach 97% through distillation under the following
conditions: the top pressure is 1 600 Pa, the bottom temperature is 190–200 °C, the top temperature is 130–135 °C, and reflux
ratio is 5:1. The best operating conditions for benzyl benzoate distillation column are: the top pressure is 400 Pa, bottom
temperature is 250–260 °C, the top temperature is 150–160 °C, and reflux ratio is 5:1. The benzyl benzoate purity can reach
95% and the fluorenone purity can reach 92%. When refined by melt crystallization, the benzoic acid purity can be improved
up to 99.6%, and the purities of benzyl benzoate and fluorenone are both above 95%. 相似文献
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Because of the superior features of boron-10 isotope in absorbing hot neutrons, boric-10 acid(H310BO3)has been used widely in nuclear industry. Boric-10 acid is obtained from boron-10 trifluoride(10BF3) by esterification and hydrolyzation. In this study, trimethyl borate-10 [(CH3O)310B] was prepared from boron-10 trifluoride(10BF3)through chemical exchange rectification. In addition, the hydrolyzation of trimethyl borate-10 was investigated with different p H values, temperatures and molar ratios of water to trimethyl borate-10. Under the optimum process conditions, high yield of boric-10 acid with nuclear industrial purity grade was realized. 相似文献
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本文作者对八十年代美国教育改革进行了独道的评述,剖析了这场改革运动的含意、影响、现实意义和历史意义。作者利用历史推进的研究方法追溯了美国五十、六十、七十以至八十年代教育改革的重点;同时探讨了各时期改革的优缺点;最后提出了八十年代教育改革所面临的问题和需要深省的改革观点。美国各时期的改革都离不开指导其改革的政治因素和政策因素。 相似文献
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序言 人类对未来的兴趣和对未来预测的严肃尝试已具有很长的历史了。但是现代“未来学研究”是由二次大战后形成的一些势力组织发起的。它们在许多工业国家同时开始研究“未来学”这门学问,这些组织是: 1.军事团体,民间团体和政府决策机构。它们认为“未来的模式”将与过去截然不同,因此,它们开始寻求各种途径。以便获取现时无望得到的东西,并且开始拟定更加有效的蓝图。 相似文献