构建网络学习资源提高民族高校有机化学课程教学质量

High-quality online course materials were reconstructed through feedback from undergraduate students and online data analysis regarding constructed learning materials on the Chao Xing Learning Platform. They were used for studying organic chemistry courses online and offline in university for nationalities. This model, based on student-centered teaching, can effectively transform students from passively accepting knowledge to actively learning and internalizing knowledge. This strategy can also enhance the students' learning initiative and the effects of learning, and hopefully be helpful to the universities in multi-ethnic areas in developing fundamental disciplined construction of organic chemistry and other courses.     

2006年国际生物-纳米-信息融合大会暨2006年国际生物芯片技术论坛

会议由清华大学、生物芯片北京国家工程研究中心、科技部、教育部、国家自然基金委等单位共同主办，由生物签片北京国家工程研究中心具体筹办。会议主要议题。     

信息拓扑指数与烷烃分子热力学性质的关系

Two topological information indices were constructed based on Randic and Wiener indices, and the values of topological information indices for 85 alkanes were calculated. The thermodynamic properties such as the standard enthalpies of formation, the standard entropies and the standard free energies of formation for these alkanes were also correlated with these topological and information indices. It is found that the thermodynamic properties calculated for both gaseous and liquid states of the 85 alkanes are in excellent agreement with the experimental values through the regression analysis.     

从月桂烯合成梨圆蚧性信息素

梨圆蚧是对果林危害较大的害虫。该虫的性信息素包括三个组分:3-亚甲基-7-甲基-7-辛烯-1-醇丙酸酯(1)、(2Z)-3,7-二甲基-2,7-辛二烯-1-醇丙酸酯(2)和(2E)-3,7-二甲基-2,7-辛二烯-1-醇丙酸酯(3)。本文介绍了通过对月桂烯进行结构改造来合成梨圆蚧性信息素,从月桂烯到1,总产率为19%。工业上从月桂烯制龋萑花醇和香叶醇,再将橙花醇和香叶醇转变为相应的氯烯醇后再还原、丙酰化即得2和3,其总产率分别为30%和28%。(以橙花醇和香叶醇计)。月桂烯可从β-蒎烯裂解而得。我国有丰富的蒎烯资源,所以开辟从月桂烯合成梨圆蚧性信息素的新途径具有重要的意义。     

尖晶石型LiMn2O4电池材料的元素掺杂

尖晶石型LiMn2O4正极材料因资源丰富、无毒、安全及制备简单、技术较成熟等优点而成为最具竞争力的新一代商用锂离子二次电池的正极材料之一.由于LiMn2O4的循环稳定性、高温(＞55℃)稳定性和大电流放电等因素限制了推广应用.本文从材料的结构组成对锂离子嵌脱过程的作用机理,论述了元素掺杂对尖晶石型LiMn2O4正极材料电化学特性的影响,指出了元素掺杂本体改性锰酸锂正极材料的方法和特点.     

这是真的吗

正变色房间你相信房间也有"感情"吗?科学家最近研发出一种会"察言观色"的房间。如果主人的心情不佳,房间就会自动把灯光调暗,播放柔和的音乐并释放清新的香味。住在这样的房间里,冷冰冰的墙壁仿佛也有了知觉。当你发出笑声时,它会变成橙色;当你发怒时,它会变成红色;当你伤心时,它也会随之渐渐转为安静的蓝色。是不是很神奇?     

告作者

为适应我国信息化建设需要,实现科技期刊编辑、出版、发行工作的电子化,推进科技信息交流网络化的进程,扩大作者学术交流渠道,本刊已加入《中国学术期刊(光盘版)》和"中国期刊网"。     

Information for Authors

Chinese Optics Letters is a short-article journal for the rapid dissemination of new, important results in all branches of optical science and technology and related fields,     

只有看透本质 才有精彩生成——对《抓住试题资源引导学生探究》的商榷与再探究

《中小学数学》(初中版)2012年第1—2期刊登了冀怀中老师的文章《抓住实体资源引导学生探究》,文章以一道中考题为素材,设计了五个问题情境,对中考题进行了系列探究,但是感觉文章翻来覆去只局限于两个正方形的旋转上,并没有探究出问题的实质,因此也就不能引领