具有半导体导电特性的腈纶研究

研究了由二价铜盐、还原剂和硫化剂浴液处理法制备导电性腈纶的影响因素、实施方法、导电性腈纶的结构和性能，确定了适宜的工艺条件。研究表明：一浴法和二浴法处理的反应历程和处理结果基本相同，但还原剂、硫化剂的匹配及用量不同；导电化处理后腈给大分子排列的规整性略有下降，宏观形态及物理机械性能无明显变化；当纤维中Ｃｕ９Ｓ５含量达１２．５％时，质量比电阻下降至１０－１Ω·ｇ／ｃｍ２以下。纤维具有明显的半导体导电特性。     

上海郊区居民和台湾高山族的体质比较

收集了上海郊区13个具有明显方言差异人群的头面部数据4项，和台湾高山族10个群体的参数进行聚类分析，发现上海郊区居民中的南方土著人群与台湾高山的遗传关系较近。     

改革材料力学试验教学提高学生综合素质

结合目前我院材料力学试验教学现状,提出几点试验教学改革的建议,以进一步提高学生综合素质。     

The genetic diversity of cen-tral and peripheral popula-tions of ratlike hamster(Cricetulus triton)

The impact of habitat fragmentation and isolation on the genetic diversity of populations has attracted much attention in studies of meta-population and conservation biology. In this work, using the randomly amplified polymorphic DNA (RAPD) technique, we studied the genetic diversity of central, peripheral and peninsular populations of ratlike hamster, which were collected in five locations of the North China Plain and its surrounding areas, in 1999. The study revealed that, ⅰ) the genetic diversity of central population of Raoyang County＞the sub-central populations of Gu'an County and Taikang County＞the peripheral population of Shunyi District＞the peninsular population of Mentougou District; ⅱ) the genetic diversities of the five populations were positively correlated to the nearest distances to the peripheral line of population distribution; ⅲ) there were significant differences of gene frequencies of some RAPD fragments among the five populations. More RAPD fragments disappeared in peripheral populations than in central or sub-central populations. The frequencies of two RAPD fragments were correlated to the latitude. This study clearly indicated that the variation of the genetic diversities of the five populations was caused by edge effect and frag- mentation through the enhanced inbreeding and genetic drift, and thus supported the view that habitat fragmentation and related edge effect reduce the population genetic diversity.     

用遗传算法求解课程表问题

课程表问题是NP完全类问题.近些年来人们尝试着用进化算法求此问题.本文根据大学编排课表的特点设计了一种全新的编码和适应值函数,并应用遗传算法求解.试验说明了该方法的可行性和有效性.     

浅议新旧住宅楼水表的改造

介绍了新建住宅楼和旧住宅楼水表改造的选材、具体步骤和注意事项。     

粉粒状物料透气性系数的测定

对经过分级的六种均齐粉粒状物料进行透气性系数测定。结果表明:球形小米颗粒((?)_p=1.70mm),透气性系数K=1.191×10~(-9)m~2,在整个固定床范围内都符合达西定律;石灰石粉((?)_P=0.900mm),K=5.831×10~(-10)m~2。文中还讨论了达西定律的适用依据和透气性系数的影响因素。     

应用不定量凸模型的遗传算法解决结构设计的优化问题

针对不定静载荷和由不定搜索而产生的最不利情况 ,应用遗传算法来解决桁架的优化问题。说明了在考虑不定量的结构设计优化问题中 ,应用遗传算法实现的高效性。