Hydrogenation properties of mechanically milled Mg2Nio.8Cr0.2-CoO/Al2O3 composites     

WANG Xiu-li  TU Jiang-ping  CHEN Chang-pin  ZHANG Xiao-bin  ZHAO Xin-bing 《Journal of Zhejiang University. Science. B》2005,(3)

Mg2Ni0.8Cr0.2-x wt.% CoO/Al2O3 (x=0.5, 1, 2 and 3) composites were prepared by mechanically milling sintered Mg2Ni0.8Cr0.2 alloy and CoO/Al2O3 compound for 45 h. The addition of CoO/Al2O3 compound resulted in the good kinetics properties of hydriding/dehydriding reaction of the composites. The composite with 1.0 wt.% CoO/Al2O3 catalyst could reach the maximum hydrogen absorption capacity (2.9 wt.%) within 5 min at 393 K under H2 pressure of 4 MPa, and can desorb rapidly at 493 K. The decomposition and synthesis of hydrogen molecule on Mg2Ni0.8Cr0.2 alloy surface was promoted by addition of CoO/Al2O3 catalyst. In addition, the formation of metallic Ni particles, strain and defects during the ball milling process also resulted in the improved hydrogenation performance of Mg2Ni-based alloys.  相似文献   

结合专业特色应用现代教育技术服务于中小学教学     

苟泽志 《保山师专学报》2005,24(3):103-104

现代教育技术的应用,深刻影响高中小学各科教学.传统的教学模式必须与现代教育技术进行整合,才能适应新课程教学改革的需要.充分发挥教育技术专业人才的主导作用,担当教育技术现代化的排头兵.  相似文献   

实时多媒体数据传输的研究及实现     

董芳  吴秀  费新元 《黔南民族师范学院学报》2003,23(3):1-4

本文主要进行RTP／RTCP与TCP协议的比较，着重分析RTP／RTCP协议对分组网上视频业务Qos的保证。在IP电话的实现中编码后的数据流采用RTP／RTCP协议来打包传送。结果表明，开发出的软件实时性好。  相似文献   

8253定时/计数器方式3计数过程的实验研究     

姜华  燕凤灵 《楚雄师范学院学报》2007,22(9):26-29

对于我系选用教材和部分参考资料关于8253定时/计数器在方式3的计数过程中表述中所存在的矛盾之处,基于武汉众友电子科技有限公司的接口实验台,提出了一个探究8253计数过程的实验方案。通过分析实验结果,指出了正确的计数过程。  相似文献   

Three dimensional couette flow and heat transfer through a porous medium with variable permeability     

Chaudhary?R.?C.?Email author  Sharma?Pawan?Kumar 《浙江大学学报(A卷英文版)》2003,4(2):181-185

This paper reports research on the effects of variations in injection velocity and permeability on the heat transfer and flow through a highly porous medium between two horizontal parallel plates situated at constant distance with constant suction by the upper plate. Due to this type of variation in injection velocity and in permeability the flow becomes three dimensional. The governing equations are solved by adopting complex variable notations to obtain the expressions for the velocity and temperature field. The skin-friction along the main flow direction and rate of heat transfer are discussed with the help of graphs.  相似文献   

Consolidation behavior of cement- and lime/cement-mixed column foundations   总被引：1，自引：1，他引：1  

蔡袁强  徐长节 《浙江大学学报(A卷英文版)》2002,3(5):507-512

The consolidation behavior of mixed in place cement- and lime/cement-mixed column was studied. Consolidation of the composite foundation was modeled as a three-dimensional axi-symmetric problem. The authors used the finite difference method to obtain the pore pressure variation with time at any location below the surface. A computer program developed by the authors was used to draw some interesting conclusions about the consolidation behaviors of cement- and lime/cement-mixed pile foundation. Finally, a combined model including the permeability coefficients of cement-mixed piles and soil, was studied and its feasibility was evaluated. Project supported by National Natural Science Foundation of China (No. 59908012) and Education Ministry of China  相似文献   

CeO2载体对Au/CeO2催化剂CO氧化活性的影响     

单文娟  刘畅 《华章》2011,(3)

采用六水硝酸铈和氢氧化钠为反应物,用水熟合成法制备了纳米Ce02.并以不同合成条件下得到的CeO2为栽体,担载了相同含量的贵金属Au,制备了具有高活性的Au/CeO2催化荆.实验结果发现,以CeO1-2h为载体的催化剂在高温区易展现出较好的活性,而以CeO2-10h为载体的催化剂在低温区易展现出较好的活性.说明载体结构对催化荆的CO催化氧化活性有决定性的作用.  相似文献   

论高校思想政治教育网络平台的建设     

曾杰  周菁 《遵义师范学院学报》2011,13(1):109-110,113

随着信息技术的高速发展特别是互联网的日益普及,网络已经成为大学生求知、社交、娱乐的重要途径。高校的思想政治教育要根据这些新的变化,加强在方法、手段等方面的改革与创新,不断拓展思想政治教育的新领域,打造高校思想政治教育的网络平台,整合校内网络资源,使之形成合力,充分发挥高校思想政治教育网络平台的功能和作用,抢占思想政治教育的新阵地。  相似文献   

Analysis on Chinese/English Code-Switching in Computer-Mediated Communication Based on Meme Theory     

张淳  石娟丽 《海外英语》2011,(7):11-14

Nowadays,computer-mediated communication(CMC) becomes one of the most convenient ways for people to connect with each other in which Chinese/English code-switching has been frequently used and widely spread.The article will memeticly interpret this language phenomenon based on the authentic examples collected from various kinds of CMC,and point out that the Chinese/English code-switching in CMC is a kind of strong memeplex which includes many different strong memes,resulting in the popularity of Chinese/English code-switching in CMC.  相似文献   

An Analysis of Foreign Language Learning Styles from the Cognitive Perspective     

王欣 《海外英语》2011,(11):67-68

From the 1970s,learning styles began to enter the domain of foreign language learning researches.Foreign language learning style is often regarded as a significant factor attributing to individual differences among language learners.Nowadays,many researchers begin studying individual learners’characteristics and exploring how different learners interact with external factors from cognitive perspective.The field-independence/dependence construct became a focus.Based on previous studies,the paper is committed to analyzing the nature of FID learners.It is expected that this research can establish a well-grounded basis for following studies.  相似文献