微波辐射下猪去氧胆酸甲酯化反应

研究了微波辐射下猪去氧胆酸的甲酯化反应 ,通过正交实验设计 ,考察了甲醇用量、加热时间以及催化剂用量对猪去氧胆酸酯化反应产率的影响。考察了催化剂的类型对产率的影响。采用高效液相色谱进行转化率监测 ,使结果更加可靠。与常规加热法相比 ,采用微波辐射加热法 ,反应时间大大缩短且产率有所提高     

Examining the impact of prior academic achievement on moral reasoning development among college students: A growth curve analysis

Moral reasoning is concerned with making decisions regarding the appropriate course of action in particular situations and has been highlighted as a critical factor that may facilitate (or impede) the effectiveness of educational programs in promoting positive outcomes. This study examined the trajectories of moral reasoning as measured by the Defining Issues Test (DIT2) for college students and to what extent there are intra-individual (within student) and inter-individual (between student) changes in moral reasoning during this developmental period. The results suggest that moral reasoning was best represented by a linear increase on the mean level and non-signi?cant variability across students. The relationship between moral reasoning and students’ prior academic attainment was also examined.     

高等专科学校英语应用能力考试问题摭析

本文通过对高等专科学校英语应用能力考虑的效度、信度、区分性、实用性和对教学的反拨作用的陈述与分析，使广大教师在大学英语教学中，处理好测试与教学的关系，重视应用能力的培养。     

The Draw-a-Scientist Test in an African context: comparing students’ (stereotypical) images of scientists across university faculties

Background: People’s perceptions of scientists have repeatedly been investigated using the Draw-a-Scientist Test (DAST). The test is used to identify people’s (stereotypical) images of scientists, which might affect attitudes towards science and science-related career choices.

Purpose: The current study has two goals. (1) Applying the DAST at a university in South Africa, the study will add to the existing research literature through its Southern African context. (2) The study will also look more closely at the link between (stereotypical) images of scientists and science-related career choices.

Sample: The DAST was applied to first-year students (n = 445) across different faculties at a South African university. If the assumption that young people’s perceptions of scientists influence their career choice is correct, one would expect differences in the drawings made by students who have opted for different fields of study.

Design and methods: The DAST was administered during orientation week of the first-year students in January 2017. Students were provided with a prepared blank sheet of paper and asked to draw a scientist and to fill in further information on the back of the paper. A content analysis applying the DAST checklist was used to analyse the images.

Results: The findings show that South African students use about four stereotypical indicators when drawing a scientist, and social science students drew stereotypical attributes more frequently when compared to students from other faculties. A typical scientist – as depicted in this study – is a man of uncertain age, who wears eyeglasses and a lab coat, and is surrounded by laboratory equipment.

Conclusions: Findings are largely in line with the international research literature. To challenge gender stereotypes, more contact between students and female role models might be essential. If (stereotypical) images really affect science-related career choices deserves further attention in future research studies.     

雅思听力对大学英语听力教学的启示

文章浅析当前大学英语听力教学中存在的一些问题,结合雅思考试中听力科的特点,阐述了雅思听力对大学英语听力教学改革的启示,提出解决英语听力教学问题的一些建议.     

CET-4听力理解基本技能的培养

通过对大学英语新四级听力理解的命题要求、题型特点做简单解释并加以分析,提出听力理解基本技能的训练方法,并就CET测试临场注意事项提出几点建议,旨在培养学生的英语听力基本技能和提高应对听力考试的能力。     

信息熵在多项选择题质量分析中的应用

多项选择题是各种测试中使用的较为广泛的题型之一,施测后对题目各选项的有效性做出判断可为评价测试质量提供重要参考依据。本文由分析多项选择问题的信息熵入手,给出多项选择题等价选法个数d的计算公式。同时,对多项选择题之间的质量比较问题,给出了使用相对熵的比较方法。     

网上考试系统的设计与实现

考试系统是网上学习环境的重要组成部分。介绍计算机化自适应考试(Computerize Adaptive Test)的基本理论依据和实施过程，构建了设计题库的数据模型并提出一个基于Web的自适应考试系统框架结构，分别阐述了检索编辑模块、成绩管理模块、组卷模块、统计分析模块、辅助模块、试卷输出处理模块等考试系统六大模块的开发，特别是手动组卷模块功能的设计和实现。     

谈语言测试的信度

信度在语言测试中非常重要，对于广大语言教师来说，重要的是从一开始就认识到不同因素对信度的影响，因为很多教师倾向于认为测试是绝对可靠的测量工具，却认识不到语言测试只能是一种间接测试，即使是最好的测试在充当测量语言能力的工具时，也有几分不准确。本文简要介绍检验测试信度的方法及提高信度要注意的主要事项。     

从普通话水平测试看高职普通话教学

普通话水平测试在一定程度上促进了现阶段普通话教学的深入。高职普通话教学应研究测试大纲,针对实际设置教学目标,循序渐进,因材施教,才能提高学生普通话水平,保证普通话水平测试的质量。