固体氧化物燃料电池的研究进展

固体氧化物燃料电池(SOFC)是先进陶瓷材料的一种重要应用,可以通过电化学反应将燃料的化学能直接转换为电能。SOFC具有效率高、性能稳定、便携、低污染等优点,可以实现能源的有效清洁利用。本文结合国内外SOFC的研究情况,分析讨论了SOFC的技术优势、地方产业优势及产业难题,并结合国家政策方面对我国SOFC产业的未来发展做了展望。     

"禁塑"时代生物塑料的应用及其发展

塑料作为高分子聚合物成为现代社会不可缺少的包装材料。生物塑料可以进行不同程度的生物降解,已经逐渐从实验研究走向市场应用。论述了生物塑料的概念与研究现状,介绍了生物塑料的种类和优势,分析了生物塑料行业的市场现状。     

几种常见低压开关柜的优缺点浅谈

阐述了市场上较常用的几种低压开关柜的结构特点和优缺点,并从安全性、经济性、可靠性等方面进行了较全面的比较,用户选择时可作为参考。     

浅谈缸内直喷发动机

简要阐述了缸内直喷技术的特点和缸内直喷发动机发展前景,重点介绍了缸内直喷发动机的綦本组成、工作原理和缸内直喷发动机的优缺点等。     

海葬优劣势的权衡分析——基于青岛市海葬发展现状与问题的调研

本篇论文主要在阐述青岛市海葬发展现状及问题的基础上，就海葬的优劣势进行比较分析，并对二者进行权衡，客观分析出海葬成为未来殡葬行业发展的主要方向之一。同时就海葬的进一步发展提出相应举措。     

Influence of group configuration on online discourse reading

Online discourse reading plays a very important role in collaborative discussions. However, not many studies have examined the influence of group configuration on online discourse note reading. The current study examined note reading workloads and participants' perceptions of the three group configurations (large whole class, small whole class, large with subgroups) in online graduate-level courses from one institute. In this mixed-methods study, we analyzed tracking logs from 25 graduate-level online courses (25 instructors and 341 students) and interviews from 10 instructors and 12 graduate students with diverse backgrounds. Findings suggest that all three configurations had their own advantages and disadvantages in fostering online discourse reading. However, our analysis suggests that the advantages of subgroup discussions in supporting note reading outweigh those of the Small and Large configurations. The overload effects in information reading due to large class sizes can be minimized by dividing students into small groups for discussion purposes. Group configuration into proper-size groups may reduce students' reading loads. Interviewees felt that the waving of small groups into large classes benefited their collaborative discussions. We conclude this paper with a list of pedagogical recommendations and new software features that may help group configuration and enhance learning in online courses. This study may have implications for both practitioners and researchers to seek optimal group configurations to achieve more fruitful online discussions through note reading.     

Ownership advantages/disadvantages of Singapore transnational construction corporations

Expanding beyond Singapore's boundaries has been a source of increased business for Singapore transnational construction corporations (STCCs). This paper analyses the significance of ownership advantage and disadvantage factors of STCCs in pursuing their international construction business, relative to other ASEAN contractors and contractors from developed countries. Moreover, this study examines if these ownership factors do vary significantly according to firm specific contextual variables in the STCCs such as size, international age, multinationality and extent of specialization/diversification. Based on responses from 22 STCCs, this study has found that the most important ownership advantage factors of STCCs were identified as coming from: (1) information, knowledge, technology and R&D capability; (2) the firm's name and reputation; and (3) management and organizational capability. Relative to established international contractors STCCs have a significant size disadvantage with reference to certain project types.     

纳米材料的进步及应用

简述国外和国内有关纳米材料的研究概况和所取得的成果 ,并分别介绍纳米磁性材料、纳米金属材料、纳米复合材料、纳米硬质合金材料及纳米航空材料等应用方面所取得的成果。     

LMDS/MMDS混合型无线宽带接入解决方案

本文着重介绍了基于无线宽带接入技术的两种主要系统，并就两种系统的优缺点进行比较，在此基础上提出了两种主要系统的混合型无线宽带接入网技术。     

湿式离合制动器在热模锻压力机上的应用现状分析

热模锻压力机上广泛应用的湿式离合制动器按离合器与制动器的布置形式可以分为分体式离合制动器和组合式离合制动器。湿式离合制动器以液压油作为工作介质,整个离合器、摩擦器腔内充满了液压油,主动轴和被动轴间的扭矩传递通过油膜间的抗剪力实现。本文着重介绍当前热模锻压力机上应用的湿式离合制动器的结构类型及相关产品,并对其关键零部件摩擦片的研究现状进行了归纳分析。