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1.
Optofluidics may hold the key to greater success of photocatalytic water treatment. This is evidenced by our findings in this paper that the planar microfluidic reactor can overcome the limitations of mass transfer and photon transfer in the previous photocatalytic reactors and improve the photoreaction efficiency by more than 100 times. The microreactor has a planar chamber (5 cm×1.8 cm×100 μm) enclosed by two TiO(2)-coated glass slides as the top cover and bottom substrate and a microstructured UV-cured NOA81 layer as the sealant and flow input∕output. In experiment, the microreactor achieves 30% degradation of 3 ml 3×10(-5)M methylene blue within 5 min and shows a reaction rate constant two orders higher than the bulk reactor. Under optimized conditions, a reaction rate of 8% s(-1) is achieved under solar irradiation. The average apparent quantum efficiency is found to be only 0.25%, but the effective apparent quantum efficiency reaches as high as 25%. Optofluidic reactors inherit the merits of microfluidics, such as large surface∕volume ratio, easy flow control, and rapid fabrication and offer a promising prospect for large-volume photocatalytic water treatment. 相似文献
2.
对第18、19届世界杯足球赛进球特征对比研究 总被引：1，自引：0，他引：1
运用录像、数理统计、文献资料、比较分析方法,对第18、19届世界杯足球赛64场比赛的进球时段、进球区域、配合方式、球员位置等进行统计、比较、分析。认为现代足球进攻战术有明显的发展趋势,这对中国足球训练以及竞赛实践有很强的指导意义。 相似文献
3.
本文提出了一种全新创建虚拟现实系统的方式,构建基于Virtools技术的虚拟实验教学,其中包含设备虚拟展示和虚拟装配系统。依托于Virtools平台的BB模块和Virtools脚本语言在计算机平台上来实现对教学设备的模拟展示以及虚拟装配的人机交互,并且利用多媒体技术如音频、视频以及虚拟环境来增强真实感。这个方法不仅适用于各高校实验教学,也适用于各种实训,以此来获取设备基本知识和相关装配技巧,也可以避免真实情景中的潜在危险或资源损耗。 相似文献
4.
The practical work of the Hong Kong A-level biology course has been dominated by recipe-type activities. This can be related to the inadequate knowledge and skills of the teachers in teaching investigative work. Based on the responses to a written test, the present study indicates that most of the biology teachers attending a post-graduate teacher education course demonstrated a poor understanding of the notion of assumptions and could not evaluate experimental evidence with reference to the assumptions made. By using small-group and whole-class discussions with guiding questions, the teachers were able to construct successfully the concept of assumptions and develop a better appreciation of the nature and limitations of the process of scientific inquiry. 相似文献
5.
Norzaini Azman Morshidi Sirat Vincent Pang Yew Meng Lai Anantha Raman Govindasamy Wardatul Akmam Din 《Journal of Higher Education Policy & Management》2019,41(1):86-103
University–Industry Collaboration (UIC) has been identified as an essential item on Malaysia’s agenda for transforming itself into knowledge and innovation-based economy. However, despite the efforts, most initiatives have had limited results. This paper reports on an explorative study that sought to understand the contemporary realities of UIC in the Malaysian context. In particular, the study identified the expectations and impediments to UIC, from the perspectives of three groups of stakeholders – the academics, the industry players and policymakers. The findings reveal a number of barriers, including cultural differences, perceived lack of academic expertise and reputation, an inadequacy of institutional policies and regulations, lack of trust, issues of intellectual property rights, and the lack of an appropriate reward system. This paper concludes by proposing policy recommendations and strategies that could be used by the government, university, and the industry to promote further and foster university-industry collaborative opportunities and initiatives. 相似文献
6.
Din Yan Yip 《International Journal of Science Education》2013,35(7):755-770
This paper reports a study of the impact of an initial teacher education programme on the development of a conceptual change model of instruction in prospective biology teachers. Analysis of the performance in teaching practice indicates that the subjects achieved significant improvement in the various skills related to this instruction model. However, mastery of these skills was not evident, especially in the response to pupils' alternative conceptions, the presentation of chalkboard layout, the use of high order questions to probe understanding and facilitate concept development, and the conduct of interactive learning activities. This can be related to the subjects' lack of teaching experience and inadequate subject knowledge, the passive learning attitude of pupils, constraints in time and resources, and the non-supportive conditions in schools. 相似文献
7.
In this article, we introduce an out-of-the-box automatic term weighting method for information retrieval. The method is based on measuring the degree of divergence from independence of terms from documents in terms of their frequency of occurrence. Divergence from independence has a well-establish underling statistical theory. It provides a plain, mathematically tractable, and nonparametric way of term weighting, and even more it requires no term frequency normalization. Besides its sound theoretical background, the results of the experiments performed on TREC test collections show that its performance is comparable to that of the state-of-the-art term weighting methods in general. It is a simple but powerful baseline alternative to the state-of-the-art methods with its theoretical and practical aspects. 相似文献
8.
Performance on a multiple-choice item in a public examination indicates that most students do not understand the principle of the bubble potometer and its limitations in measuring transpiration rate. Teaching strategies are suggested to overcome these problems by helping students to compare the bubble potometer with the weighing method, develop the concept of assumptions, and resolve cognitive conflicts. To rectify the alternative conception on the role of transpiration, an interactive activity is designed to guide students to expose their preconceptions, design investigations to test them and evaluate the validity of the original ideas. 相似文献
9.
This article discusses the role of Selim S?rr? Tarcan in the emergence of physical education in Turkey, which was an important component of the modernisation project of the Republic. Selim S?rr? Tarcan was a devoted moderniser who contributed to this process with his works and ideas in the field of physical education, a political project for the creation of strong and healthy citizens of the newly established nation-state. To analyse his contribution, we first establish the longer historical context that allows us to understand the development of modern education as a tool for shaping young generations. Second, we will focus on portions of Selim S?rr? Tarcan's biography for understanding the emergence of modern physical education and conclude by analysing his contributions to develop the archetype of healthy young citizens through modern physical education. 相似文献
10.
全民健身工程研究的新视野——对GIS应用于全民健身工程实施过程的评述 总被引：1，自引：0，他引：1
本文基于GIS应用软件技术，在分析全民健身工程实施现状的基础上，通过地理信息分析技术（如地图浏览、信息查询、图表统计等）总结与评估了全民健身工程的阶段性实施效果。通过分析本文认为在发展战略理论上，应为政府决策部门提供精准信息；在普及应用策略上，应注意完善为居民提供健身设施信息的公共服务系统；在推广层面上，应加大投入，充分发挥其实用效能。 相似文献