《河南植物志》虎耳草科补遗

报道了《河南植物志》中未记录的虎耳草科植物9种5变种(均采有标本)。     

Determination of surface topography of biological specimens at high resolution by scanning tunnelling microscopy

Although techniques are available for the determination of the three-dimensional structure of biological specimens, for example scanning electron microscopy, they all have some serious drawback, such as low resolution, the requirement for crystals or for the sample to be analysed in a high vacuum. In an attempt to develop a technique for high-resolution three-dimensional structure analysis of non-crystalline biological material, we have tested the applicability of scanning tunnelling microscopy (STM), a method that has been used successfully in the analysis of metal and semiconductor surface structures. We report here that scanning tunnelling electron microscopy can be used to determine the surface topography of biological specimens at atmospheric pressure and room temperature, giving a vertical resolution of the order of 1 A. Our results show that quantum mechanical tunnelling of electrons through biological material is possible provided that the specimen is deposited on a conducting surface.     

浅谈说课的一些感受

说课是对教师的一个较高的要求,怎样上好一门课程,怎样清楚和完整地把说课的依据、内容和重点表述出来,是一个值得研究的问题。本文就说课方面的一些体会和收获进行了一些说明。     

光学头定位系统的输入成形控制

光学头定位控制由于快速性的要求使得系统产生振荡,影响定位精度.本文应用输入成形方法抑制光头在定位时的振动.通过建立光学头机电系统的数学模型,对于无参数摄动和有参数摄动两种情形分别应用零振荡()和零振荡加微分()两种输入成形控制器进行振动抑制,计算机数值仿真结果表明,该方法对于抑制光学头定位过程中的振动具有较好的效果.     

市政工程管线综合设计概述

市政工程施工中，由于管线相碰，造成一系列经济及社会问题，遵循市政管线综合规划设计原则，进行合理的专业规划设计，能带来良好的经济及社会效益．     

大学生逃课现象调查

采用问卷调查的方法,对某大学本部除大四以外的在校本科生逃课现象进行调查研究。结果显示,大学生逃课现象较为普遍,且因年级、课程类型、上课时段以及班级人数等的不同而表现出差异性,这与学生缺乏自制力和明确的学习目标、学生对课程不感兴趣、课外活动冲击课堂教学以及社会功利风气有关。建议学校和任课教师加强学生思想政治教育、制度的建设与执行、学风建设以及课程教学改革等,解决和改善学生的逃课问题。     

Predictability of Plastic Parts Behaviour Made from Rapid Manufacturing

One of the most important issues to resolve in parts manufactured from rapid manufacturing (RM) technologies is to know their behavior working under real conditions. Total quality manufacturing (TQM) is only possible if mechanical properties are well known in the design stage depending on the processing parameters. This work is mainly focused on testing of several samples made with different selective laser sintering (SLS) parameters and technologies. This procedure is the starting point to establish a basis for designing for RM and the standardization of RM testing. The experiments and the analysis of variance (ANOVA) analyzed the effects of several factors on mechanical properties. The SLS technologies were 3DSystem and EOS. The results show which factor has a large effect on the variables and the interaction between them. The conclusions are very useful for developing rules for designing (designing for RM) and creating new standard rules (ISO, AISI, and DIN) for RM materials and parts testing. The ANOVA gives a better knowledge of the effects of these factors and eliminates unimportant parameters.     

对音乐速度差别感受阈限的研究

本实验用最小变化法测量音乐速度差别感受阈限。采用两段速度分别为=80和=120的标准音乐材料（教堂歌曲《Amazing Grace》和贝多芬《G大调小步舞曲》，Midi格式），用Finale Notepad 2008进行编辑，每一段标准音乐有10段速度渐变的对比刺激（渐变节拍分别为2和4），用Windows Media Player 11播放器播放标准音乐和对比音乐，让被试判断两者的速度有无差异。结果表明，对速度差别的感受阈限随着标准音乐材料的速度增加而提高，差异显著，验证了费希纳-韦伯定律；同时对人们生活．作曲家创作具有指导意义。     

添加剂对AN多变晶型影响研究

本文运用热分析的方法对四十余种无机、有机添加剂和几种表面活性剂及水分对硝酸铵(AN)晶型转变的影响进行了研究。结果表明这些添加剂对AN的影响应为多种因素的综合结果。     

TL生根剂促进4种观赏植物插条生根

本文报道了我们筛选的ＴＬ生根剂对含笑、绒柏、菊花和毛叶杜鹃４种观赏植物插条生根的影响．结果表明：ＴＬ生根剂能明显提高插条的生根率和每插条根数，且根长，分枝多，生根效果显著好于ＩＢＡ．