哌嗪-二氧化硫电荷转移复合物引发的甲基丙烯酸甲酯光聚合

本文研究了哌嗪 (PPZ)与二氧化硫 (SO2 )电荷转移复合物 (CTC)的制备及其作为光引发剂引发甲基丙烯酸甲酯 (MMA)的聚合 ,发现PPZ/SO2 摩尔比对聚合速率影响甚大 .当PPZ/SO2 为 1∶2时 ,形成了具有潜在引发能力的复合物 (Ⅰ ) .Ⅰ引发MMA光聚合的动力学关系式为Rp =Kp [Ⅰ ] 0 .34[MMA] 1.0 6 ,表观活化能为 2 3 7kJ/mol.并对引发机理进行了探讨     

Development of MEMS-based micro capacitive tactile probe

In this paper, a micro capacitive sensor with nanometer resolution is presented for ultra-precision measurement of micro components, which is fabricated by the MEMS （micro electromechanical systems） non-silicon technique. Based on the sensor, a micro capacitive tactile probe is constructed by stylus assembly and packaging design for dimension metrology on micro/nano scale, in which a data acquiring system is developed with AD7747. Some measurements of the micro capacitive tactile probe are performed on a nano positioning and measuring machine （NMM）. The measurement results show good linearity and hysteresis with a range of 11.6 μm and resolution of better than 5 nm. Hence, the micro capacitive tactile probe can be integrated on NMM to realize measurement of micro structures with nanometer accuracy.     

典型二元单晶REB6的电子结构和发射性能

二元单晶稀土六硼化物(REB₆)具有丰富的物理性质,其中单晶LaB₆具有优异的电子发射特性,影响二元REB₆发射性能的物理机理及其他二元REB₆是否具有良好的发射特性,需要进一步研究.本文采用基于密度泛函理论的第一性原理计算对典型二元单晶REB₆(RE=La,Ce,Pr,Nd,Sm,Gd)的电子结构、功函数进行了理论分析,并对区熔法制备的高质量单晶REB₆的热发射性能进行测试.电子结构计算结果表明,二元REB₆费米能级附近具有很高的态密度,宽域分布的稀土元素的d电子决定了REB₆优异发射性能的电子态,局域分布的f轨道对发射性能不利.功函数理论计算表明具有d态价电子的二元REB₆(RE=La,Ce,Gd)具有较低功函数.热发射测试结果表明,以上单晶REB₆ (100)晶面功函数热发射测试值与理论计算值基本相符.最终理论计算结合实验结果表明, LaB₆...     

N-甲基丙烯酰-N′-嘧啶基哌嗪及其聚合物敏化的丙烯腈光聚合

我们曾报道过同一分子中含有给电子生色基团和电子受体基团的一类功能性单体,如甲基丙烯酸-4-N,N-二甲氨基苄酯(DMABMA),N-(4-N′,N′-二甲氨基苯基代丙烯酰胺,N-(4-N′、N′)-二甲氨基苯基代甲基丙烯酰胺(DMAPMA),8-丙烯酰氧喹啉(AQ),N-丙烯酰-N′-苯基哌嗪(APP)的合成、聚合以及单独或与过氧化二酰构成氧化还原体系以引发烯类单体的聚合研究。N-甲基丙烯酰-N′-嘧啶基哌嗪(MPMP)     

Transport of Ca^2＋ Ion through a Bubbling Pseudo—emulsion Liquid Membrane with Calixarenes and Calixcrowns as Carriers

ＩｎｔｒｏｄｕｃｔｉｏｎＣａｌｉｘａｒｅｎｅｓｃｏｎｓｔｉｔｕｔｅａｖｅｒｓａｔｉｌｅｃｌａｓｓｏｆｍａｃｒｏｃｙｃｌｉｃｃｏｍｐｏｕｎｄｓｔｈａｔｃａｎｂｅｅａｓｉｌｙｆｕｎｃｔｉｏｎａｌｉｚｅｄ ,ｔｈｕｓａｆｆｏｒｄ ｉｎｇａｌａｒｇｅｖａｒｉｅｔｙｏｆｎｅｗｍｕｌｔｉｆｕｎｃｔｉｏｎａｌｒｅｃｅｐｔｏｒｓ .1Ｉｎｔｈｅｐａｓｔｔｗｏｄｅｃａｄｅｓ ,ｔｈｅｙｈａｖｅｐｌａｙｅｄａｎｉｍｐｏｒｔａｎｔｒｏｌｅｉｎｓｕｐｒａｍｏｌｅｃｕｌａｒｃｈｅｍｉｓｔｒｙａｓｕｓｅｆｕｌｂｕｉｌｄｉｎｇｂｌｏ…     

光学相干层析技术在法庭科学中的新应用

光学影像技术是法庭科学物证检验分析的重要技术手段，具有无损、原位、快速等优势。近年来，随着光学影像技术的不断发展，一些新技术、新方法不断被引入法庭科学领域并付诸应用。光学相干层析技术（简称OCT技术）是一种光学断层成像技术，具有无损、高分辨、快速、断层成像的特点，特别是其可以无损地得到材料或生物组织内部的结构信息，突破了传统二维成像只能进行物质表面分析的局限，因此可成为一种很有前景的新型法庭科学光学影像技术。本文首先介绍了自主搭建的一套三维OCT成像系统，并着重介绍了基于该系统应用于法庭科学油漆物证检验、胶带指纹显现和毛囊特征分析等方面的研究。结果表明，OCT技术非常适合用于法庭科学物证检验分析，作为其他检验的先导技术手段，获取样品内部信息，提取新型光学特征参数。由于其采用光纤化技术，还有望实现便携化、小型化，在现场勘查中开展相关应用。     

固相自引发基团置换反应制备LiNi1/3Co1/3Mn1/3O2正极材料

自从2001年Ohzuku T和Makimura Y报导LiNi1/3Co1／3Mn1/3O2正极材料以来，其一直被认为是最有可能取代LiCoO2的新型锂离子二次电池正极材料之一。氢氧化物共沉淀法是最常用的一种合成LiNi1/3Co1／3Mn1/3O2材料的方法，通过混合氢氧化物共沉淀法可以获得有着均一分布且具有很高的振实密度的球形LiNi1/3Co1/3Mn1/3O2。     

N-甲基-N-(2-甲基丙烯酰氧乙基)苯胺敏化的丙烯腈光聚合

The photopolymerization of acrylonitrile sensitized by N-methyl-N-(2-methacryloyloxye-thyl)aniline (MEMA) was studied kinetically. The photopolymerization rate of AN in DMF by using MEMA as sensitizer is proportional to 0.32 th power of MEMA concentration and 1.20 th power of AN concentration. The overall activation energy for the polymerization was found to be 4.82 Kcal/Mol. From the fluorescence analysis of obtained polyacrylonitrile sensitized by MEMA, it was confirmed that MEMA not only joined the inition but also entered into the polyacrylonitrile chains. The initiation mechanism was proposed tentatively.     

N-甲基丙烯酰-N′-嘧啶基哌嗪及其聚合物敏化的丙烯腈光聚合

The photopolymerization of acrylonitrile (AN) sensitized by N-methacrylyl-N'-pyrimidi-nopiperazine (MPMP) and its polymer, P(MPMP) was studied kinetically. It was found that the photopolymerization rate of AN sensitized by monomeric MPMP is proportional to 0.35th power of MPMP concentration and 0.85th power of AN concentration, respectively. In the case sensitized by Polymeric MPMP, P(MPMP) is proportional to 0.30th power of P(MP-MP) concentration and 1.0 power of AN concentration, respectively. The overall activation energies for photopolymerization sensitized with MPMP and P(MPMP) were determined to be 4.71Kcal/mol and 4.58Kcal/mol,respectively.From the fluorescence analysis for P(AN) senstitized by either MPMP or P(MPMP),it was confirmed that MPMP and P(MPMP) not only sensitized the photopolymerization of AN but also entered into the P(AN) chains.