基于“视联网”增强现实技术的教学应用研究

增强现实(Augmented Reality,AR)是在虚拟现实技术的基础上,将计算机生成的虚拟对象叠加到用户所看到的真实场景中,以构造出虚实结合的虚拟空间技术。将虚拟对象无缝的叠加于真实场景中帮助用户加强对环境的理解与情景的感知。文章介绍了当前增强现实技术的有关概念,结合其特点探索了其在教学中的应用。     

氢键对有机物性质和结构的影响

探讨了氢键的本质、种类及其对有机物结构和性质的影响。     

Students' reasoning about chemical bonding: The lacuna of repulsion

This article concerns a lacuna in chemistry students' reasoning about chemical bonding. Although chemistry students are familiar with the charges that make up the atom––both positive and negative––they refer only to the attraction between unlike charges. Specifically, they ignore the repulsion between the positive nuclei. We named this disregard of repulsion the lacuna of repulsion. Repulsion is a crucial component in the force-based explanation of chemical bonding, presenting the bond as a dynamic equilibrium between attraction and repulsion electrical forces. We noticed this lacuna incidentally while interviewing chemistry students for a bigger project aimed at supporting students in understanding the force-based explanation of chemical bonding. This article describes our systematic qualitative study of the lacuna of repulsion and its impact on mental models of 23 high school chemistry students. Our findings show that students use six mental models, most of them built upon each other. Beginning from a simple mental model that describes the chemical bond as electrons, continuing with the including attraction forces, and completing with repulsion and a dynamic view of the bond. Only when one considers both attraction and repulsion forces and understands the dynamic balance between them is it possible to build the force-based dynamic mental model of chemical bonding.     

基于ANSYS的Au-Al引线键合热可靠性研究

采用ANSYS有限元分析软件建立Au-Al引线键合模型考察键合区在热循环加载下的应力应变情况;并采用Coffin-Manson方程计算了在热循环加载下焊点的疲劳寿命。结果表明：随着热加载循环次数的增加,模型的应力应变将增大;施加约束后,模型的应力将减小,引线键合的寿命延长。此方法可以比较各种不同情形下Au-Al引线键合热可靠性。     

New insights into family learning for refugees: bonding,bridging and building transcultural capital

For over 20 years, researchers and evaluators worldwide have criticised the traditional formula of family learning courses for their narrow vision, and have emphasised their potential to provide a bridge between home and school experiences, building on resources that parents already have, but which are unknown or unacknowledged. This article argues that research into family learning can usefully be linked to Bourdieu's theory of ‘symbolic capitals’ to acknowledge the stores of wealth that refugee families may possess, which can be activated in the new environment to create ‘transcultural capital’– a relatively new concept in the area of migration studies. Putnam's notions of bonding and bridging capital are also helpful in the design of family learning programmes to consider how best to stimulate social cohesion at the present time. An ethnographic study of a family learning course for refugee parents in two South London schools highlights the need for an understanding of the specific strengths and needs of refugee parents. However, this can only be achieved by taking time to find out about their existing networks, the experience that they bring with them, involving them in course design and delivery, and engaging in discussion about their plans for the future.     

Reductive cyclodimerization of arylmethylidenemalononitriles promoted by samarium and catalytic amount of iodine:facile synthesis of cyclopentene derivanves

Samarium and a catalytic amount of iodine were used to obtain functionalized cyclopentenes by reductive dimerization followed by intramolecular cyclization of 1,1-dicyanoalkenes under mild conditions.     

Review: Perspectives on the metallic interconnects for solid oxide fuel cells

The various stages and progress in the development of interconnect materials for solid oxide fuel cells (SOFCs) over the last two decades are reviewed. The criteria for the application of materials as interconnects are highlighted. Interconnects based on lanthanum chromite ceramics demonstrate many inherent drawbacks and therefore are only useful for SOFCs operating around 1000℃. The advance in the research of anode-supported flat SOFCs facilitates the replacement of ceramic interconnects with metallic ones due to their significantly lowered working temperature. Besides, interconnects made of metals or alloys offer many advantages as compared to their ceramic counterpart. The oxidation response and thermal expansion behaviors of various prospective metallic interconnects are examined and evaluated. The minimization of contact resistance to achieve desired and reliable stack performance during their projected lifetime still remains a highly challenging issue with metallic interconnects. Inexpensive coati     

从Cr（CO）6看金属羰基配合物的键合特点

用分子轨道理论解释了Cr（CO）6的成键情况，揭示了金属羰基配合物的键合特点及其稳定的内在原因。     

CVD金刚石厚膜及焊接刀具的连接技术

分析了适合金刚石的焊接方法，介绍了CVD金刚石厚膜刀具的性能、应用和连接技术的研究现状，提出了金刚石实用化方面还需解决的主要焊接问题。