大学生英语写作中的连贯性问题及对策

英语写作一直是大学生英语学习的一个难题。学生在写作过程中经常出现错误，而这些错误又多集中在语篇层次上。针对这一现状，文章就语篇性七个标准之一的连贯性进行阐述，并对学生习作中的连贯性问题进行分析，进而提出了改进措施。     

Triadic interaction in clinical task-based interviews with mathematics teachers

A clinical task-based interview can be seen as a situation where the interviewer–interviewee interaction on a task is regulated by a system of explicit and implicit norms, values, and rules. This paper describes how documenting and mapping triadic interaction among the interviewer, the interviewee, and the knowledge negotiated can be used to increase procedural replicability of the interview and accuracy of drawn conclusions about the interviewee’s thinking process. Excerpts from interviews with 25 inservice mathematics teachers working on a task to make up a problem whose solution requires division of two fractions are discussed. The excerpts illustrate the relationship between methodological decisions taken by the interviewer during the interview and the applicability of the interview output to the research questions. A divergent analysis of the interviews with these teachers, which spanned over two years and were conducted by four interviewers, is used to offer a framework for analyzing data collected in clinical task-based interviews.     

简论邓小平发展理论的主要内容

本文以邓小平理论原著为依据，尽量援引其原话。从发展道路与发展阶段、发展战略步骤与发展目标、发展动力与发展手段、发展战略重点、发展速度与发展效益的统一、发展机遇与发展环境、发展捷径、发展检验标准与可持续发展、全面发展、发展的核心这十个方面对邓小平发展理论作了简要的概括和阐述．     

基于核密度估计多样性采集的背景建模算法

1IntroductionBackground subtraction methods are extensively ex-ploited for moving object detection in videos in manyapplications ,such as traffic monitoring[1],human mo-tion capture[2]and video surveillance[3]. The centralidea behind such methods is to segment foreground ini mage sequences taken from a fixed camera by com-paring each newframe to a model of the scene back-ground . Therefore , correctly and efficiently modelingand updating the background model is one of the mostchallenging aspec…     

社区教育:新成效·新认识·新经验

勃发于新世纪的我国社区教育,经过八年的推进,取得了明显的社会成效,升华了新形势下人们对社区教育的理性认识,产生出推进社区教育的宝贵经验。由于社区教育独具的特殊功能,它必然会对我国新世纪实现科学发展、构建和谐社会产生特殊的重要意义。     

全日制义务教育数学新课程标准与数学教育改革

目前进行的数学教育改革的理论基础基本上还是人们常议常新的杜威实用主义．新课标把数学定义为一个过程、一种技术，是为了贯彻杜威的实用主义思想．片面的数学定义对新课标的影响表现在：忽视基础，片面强调应用，不要推理论证没有了数学的灵魂，将教师角色错误定位．数学教育应该是改革而不应该是革命．     

芬兰社会转型中的中小学教育发展策略分析

应对新的社会转型,芬兰政府采取了一系列有效策略,以提高国家教育质量。本文主要分析了芬兰社会转型中的中小学教育几项重要发展策略,引发了几点启示。     

Conversion of CO<Subscript>2</Subscript> to useful substances with composite iron,nickel, and copper catalysts

Composite materials of Fe/Al₂O₃, which consist of small particles of iron supported by thermally stable alumina even at 500–700 °C, have been widely used in the water-gas shift reaction for natural gas reforming. Therefore, Fe/Al₂O₃ is one of the promising candidates for re-transformation of exhausted CO₂ into fuels such as alcohols and hydrocarbons. The development of a CO₂ reforming system using the composite materials of Fe/Al₂O₃ through CO₂ reduction to CO, dissociation of water into hydrogen, and methanol synthesis has been investigated. It was found that dry and steam (i.e. wet) reforming of CO₂ produced almost the same amount of CO. At a temperature above 500 °C, maximal and saturated yields of CO and H₂ from CO₂ and water were obtained. However, this CO₂ reforming system requires higher-pressure conditions from several tens to hundreds standard atmospheric pressure in order to achieve high yield and selectivity for methanol production. In this study we developed the modified CO₂ reforming system by the utilization of Ni and/or Cu instead of Fe in order to obtain other types of useful products such as CO, CH₄, and carbon, more efficiently and selectively under atmospheric pressure. When Ni or Cu was used, conversion of CO₂ was reduced to 76%, while 9% of methane was detected in the case of Ni. On the other hand, though the CO₂ conversion reduced half of the Fe, the selectivity of CO from CO₂ increased to 95% in the case of Cu.