CH_3O与CIO双自由基反应机理的量子化学研究

在QCISD(T)/6-311+G(d,p)//B3LYP/6-311+G(3df,3pd)水平上,对CH3O与ClO双自由基反应进行了理论研究.结果表明,该反应共有三个反应通道,产物分别为HOCI+CH2O,CH2O2+HCl和CH3Cl+O2(1△).不论从动力学角度,还是从热力学角度看,形成产物HOCl+CH2O的通道均是最有利的,因此为主要反应通道,这与实验观察到的结果是一致的.     

Surface Modification of a Magnetic SiO2 Support and Immobilization of a Nano-TiO2 Photocatalyst on It

This study presented an effective method to modify the surface chemical reactivity of a SiO₂/Fe₃O₄ support. The unmodified SiO₂/Fe₃O₄ support was prepared by the hydrolysis and condensation of tetraethoxysilane on the surface of hydrophilic Fe₃O₄ nanoparticles. These were then modified by a heat treatment in an ethanol/water solution under reflux. The resulting samples were characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and transmission/scanning electron microscopy. The immobilization of a TiO₂ nanocatalyst on both unmodified and modified supports was performed to investigate the effects of the modification of the magnetic silica support on the loading of a TiO₂ nanocatalyst and the photocatalytic activity. The loading of TiO₂ and the photocatalytic activity were both improved.     

Cartesian Closed Categories of F Z-domains

A subset systemZassigns to each partially ordered setPa certain collectionZ(P) of subsets. In this paper, a new kind of subset systems called directable subset systems is introduced. For a directable subset system Z, the concepts of F Z-way-below relation and F Z-domain are introduced. The well-known Scott topology is naturally generalized to the Z-level and the resulting topology is calledF Z-Scott topology, and the continuous functions with respect to this topology are characterized by preserving the suprema of directed Z-sets. Then, we mainly consider a generalization of the cartesian closedness of the categories DCPO of directed complete posets, BF of bifinite domains and FS ofF Sdomains to the Z-level. Corresponding to them, it is proved that, for a suitable subset system Z, the categories FZCPO ofZ-complete posets,FSFZ of finitely separated FZ-domains andBFFZ of bifiniteF Z-domains are all cartesian closed. Some examples of these categories are given.     

基于“营养化学”通识课程综合互动性考评体系的建立与实施

以学生为中心,以学生能力培养为导向,设计"课堂辩论""社会调查""养生文化推广"三种考试形式,以实践形式从不同侧面考核学生综合运用所学知识的能力。学生自选考试形式,参与评分过程。对学生考试成绩的分析结果显示,各种考试形式及其评分标准合理、有效,能对学生综合素质给予全面系统的评估。     

基于四丹磺酰胺杯[4]芳烃的汞离子荧光化学传感器

我们方便地合成了上沿修饰四丹磺酰胺基团的杯[4]芳烃衍生物1，发现该化合物在含50％水的乙腈中显示出对汞离子高选择性和灵敏性的识别作用，竞争实验表明多数金属离子对其检测干扰较小。机理研究结果表明荧光萃灭源于由丹磺酰胺基团到汞离子的光致电子转移过程。另外，通过研究1和1-Hg2+的荧光衰减实验，以及对比双丹磺酰胺杯[4]芳烃2和单丹磺酰胺杯[4]芳烃3对汞离子的识别作用，发现化合物1的四丹磺酰胺基团具有很好的预组织和协同作用。化合物1对汞离子的检测限为3.41×10-6 mol·L-1，这可以使1成为一个潜在的汞离子荧光化学传感器。     

VERTEX-FAULT-TOLERANT CYCLES EMBEDDING ON ENHANCED HYPERCUBE NETWORKS

In this paper, we study the enhanced hypercube, an attractive variant of the hypercube and obtained by adding some complementary edges from a hypercube, and focus on cycles embedding on the enhanced hypercube with faulty vertices. Let Fu be the set of faulty vertices in the n-dimensional enhanced hypercube Qn,k （n ≥ 3, 1 ≤ k 〈≤n - 1）. When IFvl = 2, we showed that Qn,k - Fv contains a fault-free cycle of every even length from 4 to 2n - 4 where n （n ≥ 3） and k have the same parity; and contains a fault-free cycle of every even length from 4 to 2n - 4, simultaneously, contains a cycle of every odd length from n-k ＋ 2 to 2^n-3 where n （≥ 3） and k have the different parity. Furthermore, when ｜Fv｜ = fv ≤ n - 2, we prove that there exists the longest fault-free cycle, which is of even length 2^n - 2fv whether n （n ≥ 3） and k have the same parity or not; and there exists the longest fault-free cycle, which is of odd length 2^n - 2fv ＋ 1 in Qn,k - Fv where n （≥ 3） and k have the different parity.     

Density Functional Study on the Mechanism of Collision Reaction among Protons, N2 and Water Vapor

The mechanism of collision reaction among protons, N2 and water vapor was theoretically studied using Density Functional Theory. The geometries of reactants, transition states, intermediates and products were optimized at the B3LYP/6-311 G^** level by the BERNY gradient analysis method. Transition states and intermediates have been identified by vibrational frequency analysis. The relationship among reactants, intermediates, transition states and products was affirmed by IRC calculation. The variations of energy and geometry along the IRC-determined reaction paths were described. The possible reaction pathways were represented and the optimal one was decided from the viewpoint of energy.     

营养化学课程翻转课堂的探索与实践

With its tailored learning content, flexible learning environment and directed teacher guidance, the flipped classroom in "nutrition chemistry" has effectively solved the problems of students' specialty, large number and limited time in the course of elective course. The teaching mode based on the cultivation of students' ability and the core of improving scientific literacy was constructed.     

基于核心素养培养的医学基础化学实验混合式教学模式研究

以核心素养培养为目标,改革医学基础化学实验课程,设计并实施医学基础化学实验混合式教学模式,实现在知识技能培养过程中全程育人的目的。     

PAN/PMMA凝胶聚合物电解质膜导电动力学分析

采用静电纺丝法制备PAN/PMMA(聚丙烯腈/聚甲基丙烯酸甲酯)凝胶聚合物电解质膜,用交流阻抗法测试其在不同温度下的电导率,研究温度对凝胶聚合物电解质膜离子传输性能的影响规律;并与溶液浇铸法制得的平滑膜进行对比,分析两种不同形式凝胶聚合物电解质膜的导电动力学规律,探索其导电机理与微观形貌的关系.结果发现,两种薄膜的导电机理符合Arrhenius公式,其中纺丝薄膜的离子导电活化能较低.