Thermodynamic Analysis and Comparison on Low Temperature CO_2-NH_3 Cascade Refrigeration Cycle

Intheapplicationsofindustrialandcommercialrefrig erationsystem ,iftherequiredrefrigerationtemperatureisverylow ,theconventionalvaporcompressionsystemisdiffi culttomeettherequirementbecausewhenthedifferencebe tweentheevaporatingtemperatureandthecondensingtemper atureissohighthatitishardtofindarefrigeranttomeettheneedsasthecondensingpressureisnottoohighandtheevap oratingpressureisnottoolow .Whentherefrigeratingtemper atureisverylow ,thecascaderefrigerationcycleissuitabletobeused .Itcannotonlysat…     

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

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.     

2-氯乙胺盐酸盐的合成研究

研究以乙醇胺、氯化氢和二氯亚砜为原料,以氯仿做溶剂,合成2-氯乙胺盐酸盐．实验表明:在气态氯化氢的存在下,摩尔比为1:1．04的乙醇胺和二氯亚砜在71℃下反应4小时, 可获取产率98％的2-氯乙胺盐酸盐．     

In vitro study on ribozyme against hepatitis C virus

Objective: To determine the effective nucleotide sites of ribozymes against HCV, and obtain a highly effective, nontoxic and inexpensive antisense ribozyme specific for HCV. Methods: Two effective ribozymes, targeted to HCV 5’NC region and C region, were designed and synthesized. Eukaryotic expression vectors, pSV2-gpt. CD-SR (, containing either HCRZNC or HCRZC were constructued and transfected into MT-2 cells, which had been infected by HCV. Quantitative PCR and hydridization were used to determine the effect of inhibition of HCV by ribozymes. Results: HCRZNC and HCRZC suppressed the replication of HCV by 54.7% and 62.1%, respectively. Furthermore, when both ribozymes were cotransfected into cells, they suppressed replication by 78.8%. Conclusion: Two specific antisense ribozymes have strong inhibitory effects on the replication of HCV in cultured cells, and have better effect when used together.     

运动员竞赛焦虑状态的分析

以参加第六届全国农运会田径项目的150名运动员作为研究对象,采用＂运动竞赛状态焦虑量表＂（简称CSAI-2问卷）为测试工具进行调查.结果表明：（1）不同性别的运动员竞赛焦虑状态各维度上不存在显著差异,但女运动员竞赛焦虑状态各因素得分略高于男运动员;（2）不同运动年限的运动员竞赛焦虑状态各维度上存在显著差异,运动年限越长竞赛焦虑状态各因素得分越高;（3）不同专项的运动员竞赛焦虑状态各维度不存在显著差异.     

新建地方本科院校课堂教学评价体系新论——基于邯郸学院“234”课堂教学评价体系个案研究

课堂教学评价体系的建构与实施对提高教学质量起着重要的引领作用。对照目前我国高校课堂教学评价体系现存的主要问题,新建地方本科院校应该以先进的教育理论和现代质量管理理论为参照,在外适型质量观的指导下,构建富有现实针对性的评价体系。邯郸学院234课堂教学评价体系在这方面进行了初步探索和研究。     

物联网关键技术与发展

物联网被称为继计算机、互联网之后世界信息产业第三次浪潮。文章首先解析物联网的基本概念和特征、物联网体系架构,然后归纳物联网涉及的关键技术,最后总结物联网标准化发展现状、问题,并提出物联网标准化发展建议。     

P2P技术在校园网络的应用研究

Peer-to-Peer(P2P)网络被喻为第三代网络,采用的是点对点分散式网络架,它不需要服务器的中转,使用户与用户之间的连接更加方便、快捷,更大范围地实现资源共享。本文首先分析了目前校园网络的体系结构的存在的资源共享瓶颈,通过P2P技术与传统的校园网络构架的对比,在分析P2P技术的关键技术与优势的基础上提出在校园网络引入P2P技术的重要性与可行性。     

《诗品下·序》疑难问题辩说(上)

从序文形式与内容两方面 ,辨说《诗品下·序》疑难问题。其中 ,专节辨明有关诗歌创作的自然声律理论 ,贯通古今作出综合考察与探索 ,有助于古文论的现代“转化”与钟嵘诗论的深入研究。     

溴硝基丙二醇的合成和防腐活性研究

合成了防腐剂2-溴-2-硝基-1,3-丙二醇,通过IR波谱和元素分析对其进行表征,并对其防腐性能和毒性研究.