吡啶气相光氯化反应理论研究──加成反应机理的过渡态和IRC解析

通过PM3方法研究氯自由基与吡啶分子加成反应的结果表明,生成不同产物2－氯吡啶、3－氯吡啶、4-氯吡啶的每一个反应通道都存在两个过渡态,生成2－氯吡啶反应路径主过渡态的能量及活化能最低,分别为-110293.6和139.2kJ/mol,反应优先生成2－氯吡啶,与实验结果一致.生成2－氰吡啶反应过程(IRC)相关的键长、键级和原子净电荷变化表明,吡啶环反应部位C原子与Cl加成形成C-Cl键主要与共轭双键断裂同步,而C-H键的断裂主要与共轭双键的重新形成同步.反应进程中氯原子净电荷从增加到减少的变化是氯原子诱导效应吸引电子和p－π共轭电荷平均分布等相互作用的结果.     

Analysis of the effect of sidewall on the performance of 6H-SiC Schottky barrier source/drain NMOSFETs

Between source/drain and gate of SiC Schottky barrier source/drain MOSFET (SiC SBSD-MOSFET), there must be a sidewall as isolation. The width of sidewall strongly affects on the device performance. In this paper the effect of sidewall on the performance of 6H-SiC SBSD-NMOSFET is simulated with the 2D simulator MEDICI. The simulated results show that a sidewall with width less than 0.1μm slightly affects the device performance. However, when the width of sidewall exceeds 0.1μm, the conduction does not occur until the drain voltage is high enough and saturation current sharply decreases. The effect of the sidewall on device performance can be reduced by decreasing the doping concentration in the epitaxial layer.     

Study on Coupled Chemiluminescene Reaction of Ru(l,10-PhenanthroIine)32+-Methanol-Ce(Ⅳ)

It was reported that some hydroxyl/carbonyl carboxylic acids can enhance the chemiluminescence light emission intensity of Ru(phen)₃²⁺(Phen=1,10-phenanthroline) with Ce(Ⅳ). Further studies showed that methanol can also enhance the light emission intensity. In sulfuric acid medium, methanol was oxidized by eerie sulfate, the rate of oxidation depended directly on the concentration of cerium(Ⅳ) and methanol. The reaction rate changes inversely with sulfuric acid. The reaction occurs without the intermediate formation of a complex.     

激光诱导荧光技术测量OH自由基的建立和研究

氢氧自由基（ＯＨ）在对流层大气化学中起着重要的作用,因此,对其浓度的测量具有重要意义。本文利用气体扩张激光诱导荧光技术（ＦＡＧＥ）建立了ＯＨ测定系统,对其进行了标定,得到归一化荧光信号（Ｓ）与ＯＨ自由基浓度的较好的相关关系,并对可能存在的干扰进行了分析。     

Quasi-periodic and Non-periodic Waves in (2+1)-Dimensional Nonlinear Systems

New exact quasi-periodic and non-periodic solutions for the (2 1)-dimensional nonlinear systems are studied by means of the multi-linear variable separation approach (MLVSA) and the Jacobi elliptic functions with the space-time-dependent modulus. Though the result is valid for all the MLVSA solvable models, it is explicitly shown for the long-wave and short-wave interaction model.     

Effective Quark-Quark Interaction Created by Quark-Antiquark Pair Excitation

By means of the quark-antiquark pair creation model via one-gluon exchange,the effective interaction among quark,which is equivalent to the meson exchange intervening between two hadrons,is discussed.It is shown that this process includes interactions not only between two quark,but also among three quark.Obviously,such effective interaction is more general than one gluon exchange potential (OGEP).     

一种新型的纳米功能材料:磁性纳米镁铝水滑石

本文将磁性基质与镁铝水滑石进行组装首次合成出一种新型的纳米磁性功能材料—磁性纳米镁铝水滑石。这种新型纳米功能材料的XRD及TA结果表明,镁铝水滑石赋予磁性后并没有改变其层状结构的典型特征。样品的TEM图表明,磁性基质的加入后样品的颗粒粒径并没有明显增大,且保持在20～50nm之间。对磁性镁铝水滑石磁性能的考察结果表明,样品的比饱和磁化强度随磁性基质含量的增加而线性增加。     

基于学科理解的电功视角下“化学反应与能量”教学

基于教师对电化学反应与能量的学科理解，抽提和凝练本原性问题：系统与环境之间的能量传递形式只有“热”吗?电化学反应如何实现电功传递?通过“电功”视角下认识化学反应与能量的主题大概念教学设计与实施，帮助学生建构和完善“电功”认知模型，应用模型进行探究和迁移，形成电化学主题特质性思维方式和方法，充分落实化学学科核心素养。     

铜(Ⅱ)和镍(Ⅱ)Salamo型配合物的合成、晶体结构、Hirshfeld表面分析、热稳定和荧光性质

基于香豆素类配体H₂L合成了2个新的单核铜（Ⅱ）和三核镍（Ⅱ）配合物，[CuL]（1）和[Ni₃（L）₂（μ-OAc）₂（CH₃OH）₂]·CH₃OH（2），并通过元素分析、红外光谱、紫外-可见吸收光谱，单晶X射线衍射，荧光光谱，热稳定性（TGA）和Hirshfeld表面分析对其进行了表征。X射线晶体学证明在配合物1中，位于[N₂O₂]空腔的铜（Ⅱ）离子是四配位的，形成了一个扭曲的平面四边形构型。同时，在配合物2中所有的镍（Ⅱ）离子都是六配位的、具有扭曲的八面体几何构型。甲醇分子作为配体参与配合物2的配位作用。在配合物1和2中，氢键和C-H…π相互作用形成了强的超分子结构。此外，对配合物1和2的热稳定性和Hirshfeld表面分析进行了仔细的分析，并对配合物1和2的荧光性质也进行了研究。