共查询到20条相似文献，搜索用时 0 毫秒
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近年来,国内学者对翻转课堂的相关研究主要集中在翻转课堂的阐述介绍和教学模式探究等方面,很少从实践的角度进行探究。笔者对北京石油化工学院的大学英语课程进行了翻转课堂教学实践,并针对出现的问题进行了反思和再实践;根据学生的英语水平和学习能力调整翻转课堂的实践模式,重新定位师生角色,有针对性地完善课前视频材料,摸索出了切实可行的翻转课堂实施步骤和学习模式。\"翻转课堂\"给大学英语教学带来了实效,提高了学生的英语综合应用能力。 相似文献
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An innovative hydrocyclone was designed, in which a conical filtering wall replaces the conical section, producing another liquid stream leaving the equipment, besides underflow and overflow streams. The influence of the inlet diameter of a filtering hydrocyclone was analyzed by an experimental and computational fluid dynamics study. Data from conventional hydrocyclones of the same configurations were also obtained. Under identical operating conditions and geometry, the filtering hydrocyclone presented a better performance than the conventional device. Under the experimental conditions evaluated, an about twofold increase in inlet diameter reduces the Euler number significantly. 相似文献
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诸多的化工单元操作过程中,普遍存在着"边界层"现象。"边界层"的存在对化工单元的操作过程会产生明显的影响。本文描述和类比了多种"边界层"的特征,并在物理化学的知识层面上对其产生机理进行了阐述,最后指出通过削弱边界层可以提高动量传递、质量传递和热量传递的速率和效率。 相似文献
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Chemical Engineering students are usually exposed to stress and anxiety situations during university period. Authors consider that a reduction in students’ stress levels can improve their academic results. A new experience based on the introduction of gamification strategies by incorporating a new methodology for solving engineering problems called PWD (problems without data) was proposed. This was related with a specific app design. Two students’ groups were randomly done and, despite having the same academic content and teacher, only one group used this methodology. Results showed that using these new elements for a subject called Basic Operations, belonging to the area of Chemical Engineering area of the University of León, the comfort and stress level of the students improved significantly. Thus, the average value of the stress perceived by the students, which initially was above a value of 5 out of 10, was reduced for those students who have followed the proposed methodology to levels below 3.5. Additionally, an related to the academic degree, a difference of 1.5 points (out of 7) was found for the students who had used the PWD methodology with respect to the control students. 相似文献
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Volodymyr V Tarabara 《Chemical engineering science》2003,58(1):239-246
Scaled-down models of industrial filtration units are often used in laboratory studies of membrane processes. Knowledge of the flow field and shear stresses at the membrane surface is vital for the accurate interpretation of bench scale experiments. In this paper, we present results of computational fluid dynamics modeling of the flow within the SEPA CF flat sheet membrane filtration cell operated at low recoveries. The problem was formulated as the steady-state isothermal laminar flow of incompressible Newtonian fluid. Pressure, velocity, and shear stress distributions were computed with resolution for different average inlet velocities. Flow was found to be unidirectional over most of the channel area with exception of the corners of the channel. Stagnation areas in dead ends of inlet and outlet tubes and in the channel areas behind duct entries as well as local regions of high shear in duct-channel transition areas were observed. The relation between the highest shear rate created in this geometry and the average inlet velocity is given. 相似文献
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Frederick Bloom 《Chemical engineering science》2003,58(2):353-365
A model for a semi-batch flotation separation process has been developed, based on available microprocess probabilities, and compared to experimental data obtained using a WEMCO laboratory flotation cell. In general, the model predicts the correct experimental trends. In many cases, the model also predicts removal efficiency very well. Parametric studies reveal that the model predictions are sensitive to a stability parameter, the turbulent energy density in the flotation cell, the contact angle between the solid particle and fluid, and the ratio of initial-to-critical film thickness. 相似文献
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Branislav M. Ja?imovi?Srbislav B. Geni? Dimitrije R. Djordjevi?Nikola J. Budimir Marko S. Jari? 《Chemical Engineering Research and Design》2011,89(6):561-572
The paper deals with the tray-to-tray method for determining the required number of trays in columns with intensive entrainment of liquid when the operating line of the “dry working regime” is not straight and with a small concentration of diffusing component in gas. Presented calculations show that the number of transfer units for gas and liquid should be calculated using the AIChE method accompanied with longitudinal mixing according to Gilbert properly transformed for case of diffusion through stagnant film. The suggested method can be applied for TEG dehydration absorbers-columns for dehydration of natural gas using triethylene glycol with system factor SF = 0.5. 相似文献
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The Chemical Engineering curriculum at Polytechnique Montreal is structured to gradually provide more and more autonomy to the students. The third-year Unit Operations is taught using an outcomes-based approach and represents a turning point in the undergraduate curriculum where rubrics-based assessments overtake normative assessments. This begs the question: is it really necessary to divulge the average to students following assessments? Those from a more industrial background see the average as an unnecessary crutch for students, while the more academically inclined see it as a useful pedagogical tool to provide feedback and help students determine if they have attained their learning objectives. To settle this debate, we set into motion a yearlong study during which the average results to tests were withheld. Students were asked to predict their grade and the class average, and provide feedback on the assessment process. Results show that students are able to predict the average, but have difficulty predicting their individual performance (especially before a test, where more than 50% of students are off by a factor of more than 10%). Students award more importance to their personal sense of learning satisfaction than their position with respect to the average, and do not systematically use the average to plan study time (despite preferring to know it). Thus, it may be possible to substitute alternate frames of reference to the class average in an outcomes-based course, but this is not necessarily desirable and should at the very least be the subject of a more open discussion. 相似文献
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Mieczys?aw Trypu? Katarzyna Bia?owicz Krzysztof Mazurek 《Chemical engineering science》2004,59(6):1241-1246
Investigation was carried out on the optimal conditions of the synthesis of KVO3 and Cl2 from KCl and V2O5 in the presence of atmospheric oxygen. The research was performed for the temperature range 673- for 1-. The influence of the air flux rate on the reaction yield was investigated. 相似文献
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Katarzyna Białowicz Krzysztof Mazurek Urszula Kiełkowska Mieczysław Trypuć 《Chemical Engineering Communications》2013,200(12):1467-1475
Investigation was carried out on the optimal conditions of the synthesis of KVO3 and Cl2 from KCl and V2O5 in the presence of atmospheric oxygen. The influence of the excess of KCl relative to V2O5 was investigated. Also, the effect of quartz sand introduced into the reaction mixture on the yield of KVO3 synthesis was determined. The obtained product of synthesis was isolated from the post-reaction mixture. 相似文献
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Alexandru Woinaroschy 《中国化学工程学报》2016,24(5):553-557
A short presentation of chemical engineering evolution,as guided by its paradigms,is exposed.The first paradigm–unit operations–has emerged as a necessity of systematization due to the explosion of chemical industrial applications at the end of 19th century.The birth in the late 1950s of the second paradigm–transport phenomena–was the consequence of the need for a deep,scienti fic knowledge of the phenomena that explain what happens inside of unit operations.In the second part of 20th century,the importance of chemical product properties and qualities has become essentially in the market fights.Accordingly,it was required with additional and even new fundamental approaches,and product engineering was recognized as the third paradigm.Nowadays chemical industry,as a huge materials and energy consumer,and with a strong ecological impact,couldn't remain outside of sustainability requirements.The basics of the fourth paradigm–sustainable chemical engineering–are now formulated. 相似文献
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As part of an effort to enhance students' first year experience, all Chemical Engineering students in Universiti Teknologi Malaysia are required to take the Introduction to Engineering course. This course is designed to stimulate students’ passion and strengthen motivation for further engineering studies, as well as to enhance their technical knowledge and relevant professional skills. To investigate the impact of the course on students’ knowledge of engineering, an exploratory study is conducted through an open-ended survey, given at the beginning and end of the semester. The analysis shows that the ITE course successfully served the purpose of raising awareness about engineering profession among students, while motivating them through student-centred learning approaches. A qualitative study is also conducted by analysing reflection journals submitted by students to identify the improvement on professional skills that students have developed as they go through the course. This study concludes to show that first year engineering students who have gone through the activities in the course have understood the role of engineers and their job functions. They have also managed to develop professional skills as part of their initial journey to become good engineers. 相似文献
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Clifford Y. Tai Meng-Chun Chang Chi-Kao Wu Yen-Chih Lin 《Chemical engineering science》2006,61(16):5346-5354
The crystal growth rates of calcite were evaluated in a dense fluidized-bed crystallizer using a constant-composition method. Several operation variables related to solution properties that affected growth rate, including supersaturation, pH, ionic strength and activity ratio, were systematically investigated. Then the crystal growth-rate data were analyzed by the two-step crystal growth model and thus the mass-transfer and surface-reaction coefficients were obtained. The effects of the solution properties on the two individual coefficients were observed. Good explanations on these effects are needed. 相似文献