略论休克尔(4n 2)规则与有机物芳香性判别

本文就如何应用休克尔(4n 2)规则,方便、快速、准确地判别稠环、离子和富瓦烯等复杂体系的芳香性、进行了一些探讨,拓宽了休克尔(4n 2)规则的应用范围.     

杜威与施瓦布的科学本质观与科学教育观比较

文章从社会学视角比较分析了杜威与施瓦布在科学本质观上的异同及成因。以及二者为把相应科学本质观传达给学生，而提出的改革课程与教学的主张，并在此基础上探讨了他们对如何看待科学本质，以及对我国j前课程改革的启示。     

Si3N4陶瓷二次部分瞬间液相连接数值模拟

利用热弹塑性有限元方法，通过瞬态热结构直接耦合，模拟Si3N4陶瓷二次部分瞬问液相连接过程，分析了连接接头残余应力分布状态和中间层对此连接接头应力分布的影响。结果表明：陶瓷外表面靠近连接界面的附近存在最大拉伸应力；采用Ti／Cu／Ni／Cu／Ti中间过渡层的接头应力出现大幅度的降低；陶瓷与金属之间热膨胀系数的巨大差异是导致残余应力的主要原因，采用中间过渡层能缓和接头的残余应力，提高接头强度。     

基于.NET架构的J2EE技术设计与开发远程教学系统平台

提出并实现了一个基于.NET架构的J2EE标准,以WebService为基础的web服务器构建多媒体远程教学系统平台,以此教学平台框架开发的多媒体远程教学系统具有更高的跨平台性和互动性。利用基于.NET架构的J2EE标准,提出了远程教学系统平台的系统设计与实现方法。     

Comparing Student Performance and Growth in 2- and 4-Year Institutions

This study examines the organizational characteristics of 51 higher education institutions in relationship to student performance and growth. The study first finds that organizational measures of mission, size, wealth, complexity, and selectivity are statistically represented by the 2-year versus 4-year college mission. Findings indicate that 2-year and 4-year campuses indeed do exert significantly different influences on undergraduate GPA and self-reported intellectual growth. Next, the study uses both OLS regression and HLM to examine these influences. High school percentile rank and college classroom experiences are better predictors of Cum GPA at 4-year institutions, while student effort is a better predictor of GPA at 2-year institutions. Whereas the most important predictors of Cum GPA include precollege measures such as high school percentile rank and SAT score, the most influential predictors of student intellectual growth are campus experiences including classroom vitality, peer support, student effort, commitment, and involvement. Controlling for all other variables, students at 2-year institutions receive higher grades, and students at 4-year campuses experience more growth.     

创建高效J2EE Web应用研究

通过对创建J2EE Web技术的研究，提出了对控制器、业务层模型和数据库访问的改进方法.这些方法能优化Web性能，提高访问速度，对创建高效的Web应用具有一定的借鉴作用.     

Turning scientific and technological human capital into economic capital: the experience of biotech start-ups in France

This paper examines how scientific and technological (S&T) human capital is transformed into financial capital through the creation of firms by scientists. The analysis is based on a database describing the positions held by 132 founders from 62 French biotech SMEs. It shows that star scientists engage in highly risky but also valuable firms. Less famous scientists must develop their human capital rather than valorising a stock. The paper concludes by pointing to three paradoxes concerning the commitment and compensation scheme of star scientists and the managerial position of less known scientists.     

基于J2EE平台的分布式运销系统分析与设计

当前许多企业都在异地建立分支机构，它们负责其所在地的各种业务活动，这就不可避免地产生了总部和分支机构之间的信息共享和交互问题。那么如何实现分布于广阔地理范围的分支机构与总部的信息集成就成为企业信息化道路上迫切需要解决的问题之一。本文以我们自行设计和开发的准噶尔能源公司运销管理系统为例来介绍基于J2EE架构的分布式信息系统的分析与设计。     

La掺杂Co-Fe-O纳米磁性材料的制备和表征

以Fe(NO3)3·9H2O,Co(NO3)2·6H2O和La2O3为原料,首先制备出晶粒细小的盐渍化碱式碳酸盐前驱体,在400℃、500℃、600℃、700℃、800℃分别烧结1h,制备出CoFe2O4和LaCo0.4Fe0.6O3纳米磁性材料,并用XRD、SEM和IR对样品进行表征,研究了不同的烧结温度和La掺杂对物相的形成及颗粒大小的影响.     

支持手机检索的技术方案

随着手机的日益普及，人们越来越希望能利用手机从Internet获取各种信息，本文介绍了满足这一需要的两种技术方案。