紫外光快速成型中树脂固化过程的研究

为了确定快速成型中树脂固化线条的理论模型，对扫描动作和固化过程进行了详细分析．由于明确了实际扫描动作是由匀速运动和非匀速运动所组成的，因此实际扫描的固化线条是非均匀一致的．根据树脂曝光理论，建立了固化线条的横向和纵向截面形状的数学模型．揭示出整个固化线条呈哑铃形，其横截面轮廓呈抛物线形．在x轴上的位移等于光斑直径时，树脂微元的曝光时间最长，固化深度最深．采用实际的固化线条对数学模型进行了对比验证，其结果表明固化线条基本与理论模型一致，这对于改善成型质量具有理论指导意义。     

浅谈初中化学教学中对学生能力的培养

文章阐述了在初中化学教学中如何来培养学生的创新思维能力、观察力、注意力和记忆力等能力。     

计算机藏文编码性能指标分析

从规范性、兼容性、一致性、完备性四个方面分析了计算机藏文国家标准编码性能指标,论述了建立藏文编码体系的必要性和可行性     

神经元网络技术和偏最小二乘法在定量分析和构效关系方面的比较

在光度计／计算机联机系统上利用人工神经网络反向传递算法和偏最小二乘法对五组分有机物混合体系的紫外光谱数据和芬太尼构效关系数据同时进行了定性定量分析，对比和研究，结果表明，反向传递模型具有良好的定性分类能力和定量预测能力；偏最小二乘算法的定性分类效果稍差，但定量预测能力优于反向传递算法。     

基于神经网络的最大似然空间信号参数估计

本文主要研究了用Hopfield神经网络实时实现最大似然多信号源空间参数估计方法。报传统最大似然信号参数估计的理论和Hopfield连续状态神经网络特性后，给出了一种实现最大似然空间参数估计模型，该神经网络模型的模拟实验结果表明，用Hopfield网络实时实现的信号参数估计方法具有与传统的最大似然参数估计法拥有同样的理论分析结果。     

氢致脆化区开裂模型应用于计算门楹值应力强度因子

依据氢进入裂纹尖端区促进局部塑性流动的认识，本建议并发展了一个氢致脆化区开裂模型。首次推导出了确定氢致裂纹扩展门楹值应力强度因子以及环境氢压与门楹值应力强度因子关系的理论公式，定性和定量的分析相符于ＡＩＳＩ４３４０超高强钢的实验结果。     

新型外燃旋流热风炉内流动与传热过程数值计算

阐明中小型高炉的风温由1000℃左右提高到1 250～1 300℃的主要措施是将煤气与空气双预热;提出应用高速烧嘴和新型外燃旋流热风炉来预热助燃空气,烧单一煤气可以实现高炉1 250～1300℃高风温.对炉内流动与传热过程进行的数值计算结果表明,在蓄热球床表面没有偏流,气流及温度分布均匀.在中试炉上测量的烟气温度分布与计算结果基本吻合.     

Obtaining the transgenic poplars with low lignin content through down-regulation of 4CL

The antisense 4CL (4-coumarate: CoA ligase)gene was transformed into triploid Chinese white poplar(Populus tomentosa) mediated by Agrobacterium tumefaciens.PCR and Southern blot analysis indicated that antisense 4CLgene had been integrated into the genome of the transgenicChinese white poplars. The antisense gene had also beenexpressed, which was indicated by RT-PCR and Westernanalysis. Klason lignin content assay showed that repressionof 4CL expression could result in remarkable reduction oflignin content in transgenic poplars, with most reduction of 41.73% compared with that of wild type in this paper. Butthere is no significant difference in holocellulose content be-tween trans- genic and wild poplars. We considered that 4CLmight not be the metabolism control point between ligninand carbohy- drate biosynthesis. The stems of transgenicpoplars displayed red-brown color with different levels afterthe bark was peeled, while those of untransformed plantswere white. No visible differences in growth and developmentwere observed between transgenic and wild plants. Wiesnerreaction analysis of the transgenic plant stems with reducedlignin content exhibited red color, while that of untrans-formed plant was typically purple-red.     

一些聚合物地中相微乳液物性的影响

研究了水解聚安、黄原胶和木质素磺酸盐对中相微乳液相体积、粘度和界面张力的影响，实验结果表明：含有聚丙烯酰胺时，中相微乳液的相态、增溶参数、中相与下相间界面张力及中相粘度均无明显变化。生物聚合物对中相微乳液的物理影响也不大，木质素磺酸盐册对微乳液的形成产生明显影响；随着木质素磺酸盐浓度的增大，微乳液由中相转变为相，相应的物理参数亦有变化 。     

Urban Railway Accessibility

Effective use of urban rapid railway systems requires that the railway systems be effectively con-nected with other transportation modes so that they are accessible. This paper uses the logit model and data to analyze the factors influencing railway access choices in a railway choice access model. The results indicate that access time, access cost, and access distance are factors significantly affecting railway access choices. The user’s income significantly affects the probability of choosing to walk rather than to take a taxi, but is not related to choosing buses or bicycles. Vehicle ownership significantly affects the probability of choosing a taxi, but is not significantly related to the other modes. The conclusions provide an analysis tool for urban railway planning and construction.