DETECTION OF DNA-PSORALEN PHOTOADDUCTS in situ

Abstract— An immunological method, with the use of specific immune serum, has been developed for detection of 8-methoxypsoralen (8-MOP) photoadducts to DNA, formed in situ in cell nuclei, after combined treatment with 8MOP and UV-A irradiation (Zarçbska et al. , 1978). Lymphocytes fixed on slides or in suspension, and cryostat sections of different mammalian tissues, served as antigenic substrate, after treatment with 8-MOP and UV-A in vitro. Specific fluorescence in these substrates was detected in the nuclei after treatment with 30 ˜ 140 kJ/m² UV-A in the presence of 0.1-0.3 μg/cm² 8-MOP. PHA-stimulated-lymphocytes appeared to be the most sensitive substrate.
However, hairless mice treated with high doses of UV-A in vivo , 70 ˜ 360 kJ/m² did not reveal a specific fluorescence of epidermal nuclei, unless a high local concentration of 8-MOP was attained.
The apparent discrepancy in the level of photoadduct detection between the in vitro and in vivo treated specimens was explained by the low number of DNA-8-MOP-photoadducts formed in vivo under these experimental conditions. The relevance of these findings to the role of DNA-8-MOP-photoadducts formed during PUVA photochemotherapy is discussed.     

场致发射显示器驱动电路研究进展及其性能研究

场致发射显示是一种新型的平板显示技术，场致发射显示器继承了传统的阴极射线管显示器的优良特性，兼有液晶等薄型平板显示器的优点，具有广阔应用前景。介绍了几种不同阴极结构的场发射显示器工作原理及相应的驱动电路，分析并比较了二极管型和三极管型两种场致发射显示器的驱动电路，对新型场致发射平板显示器的理论研究具有参考意义。     

多功能夫琅禾费衍射演示仪的研制

针对目前国内夫琅禾费衍射演示仪存在的问题,研制了一种＂多功能夫琅禾费衍射演示仪＂,实现了26种衍射缝的夫琅禾费衍射的演示实验及相应的计算机（变参数）模拟仿真实验,具有演示与仿真一体化、演示种类多、演示效果明显,自动快速、使用方便、功能多样等特点,能够满足光学课程对夫琅禾费衍射进行演示实验的要求。     

激光熔覆硬质合金强化化纤切断刀的研究

在机械压制法预置硬质合金WC/Co粉末的条形55Si2Mn弹簧钢上,用激光熔覆方法制备了化纤切断刀.调整熔覆层粉末配方中Al、TiC的加入量,结果表明加适量的Al粉能有效地抑制气孔,加TiC粉末能提高熔覆硬度.通过优化激光熔覆工艺参数,得到了无气孔缺陷、组织性能良好、硬度达到HV0.21250的激光熔覆层,达到了化纤切断刀的性能要求.     

ON QUOTIENTS OF BRAID GROUPS

ABSTRACT.

Let G be the group ?[t, t ^?1] x ?. By studying the action of the braid group B_n on the set Gⁿ , we obtain representations of B_n into a wreath product of the symmetric group and the general linear group over ?[t, t ^?1]. This in particular recovers the Burau representation of the braid group. Furthermore, some quotients of the braid group are obtained by using the representations found.     

含双间隙连杆机构动力学仿真与实验

为考察含双间隙连杆机构的动力学行为,进行了仿真和实验研究。在仿真中,基于ADAMS软件建立了一个非线性接触力模型。同时,设计和建立了一个实验装置来对仿真结果进行验证。分别讨论了间隙尺寸、加载频率和加载力幅值对接触碰撞力的影响。结果表明,间隙的存在会影响传递力曲线,使机构产生明显的振动冲击,间隙大小和加载速度是影响机构动态响应的主要因素。实验结果证明了本文模型的正确性。     

基于波谱技术的茶树生长与茶叶品质信息快速检测研究进展

波谱技术快速获取茶树生长和茶叶品质信息对提高茶叶生产信息化、产业化水平,保障茶叶品质和安全具有重要意义。阐述了波谱技术在茶树生长和茶叶品质信息快速检测的研究进展和发展趋势。重点介绍了红外光谱,荧光光谱、拉曼光谱、质谱等在茶树生长信息获取(氮、叶绿素、病虫害信息等)、茶叶品种分类、茶叶分级、茶叶内部品质检测(茶多酚、儿茶素、咖啡碱、氨基酸、农药残留等)、茶饮料和加工品的品质检测以及相关检测设备等方面的研究进展和应用情况,简述了茶树生长信息获取方法、传感仪器和产业化应用的研究和发展趋势。选择合适的预处理和化学计量学方法能有效增加模型效果,减少冗余数据,为基于波谱技术便携式仪器的开发提供可能。基于波谱技术便携式仪器和在线检测仪器开发仍是今后实现该技术应用和推广的重点。首次介绍了波谱技术在茶叶生产加工领域的应用成果和研究进展,涵盖茶树生长、茶叶加工、茶叶和茶加工品品质安全等多方面内容,并论述波谱技术在茶叶产业应用存在问题和将来发展趋势。     

A New Algorithm of Time Stepping in Dynamic Viscoelastic Problems

ＩｎｔｒｏｄｕｃｔｉｏｎＡｎｕｍｂｅｒｏｆｍａｔｅｒｉａｌｓｉｎｅｎｇｉｎｅｅｒｉｎｇｃａｎｂｅｃｌａｓｓｉｆｉｅｄｉｎｔｈｅｃａｔａｌｏｇｏｆｖｉｓｃｏｅｌａｓｔｉｃｉｔｙ ,ｉｎｃｌｕｄｉｎｇｒｏｃｋ ,ｓｏｉｌ,ｐｏｌｙｍｅｒ,ａｎｄＥＲ ＭＲｍａｔｅｒｉａｌｓｅｔｃ .[Ｃｈｒｉｓｔｅｎｓｅｎ 1 982 [1],ＴＡＯ 1 999[2 ]] .Ｔｈｅｄｙｎａｍｉｃａｎａｌｙｓｉｓｏｆｖｉｓｃｏｅｌａｓｔｉｃｐｒｏｂｌｅｍｓｉｓｒｅｌａｔｅｄｔｏｔｈｅｔｉｍｅｄｅｐｅｎｄｅｎｔｓｏｌｕｔｉｏｎｓ.Ｅｖｅｎｔｈｏｕｇｈｄｉ…     

奶粉中唾液酸的测定方法

利用酸水解把奶粉中的唾液酸释放出来，通过聚丙烯酰胺凝胶除去奶粉中大量乳糖的干扰。利用Cu^2＋和Cr^3＋协同催化唾液酸与间苯二酚的显色，用乙酸丁酯-正丁醇萃取有色物质，在610nm处测定牛奶中唾液酸含量。方法的线性范围0～55．90mg／L，回收率为94％～96％。