一种基于PVC膜电极的电位式葡萄糖传感器的研制

以三庚基十二烷基碘代季铵盐为电活性物质的PVC膜电极, 对过氧化氢和六价钼的络合物具有良好的电位响应. 将葡萄糖氧化酶固定到PVC膜电极表面, 制备成电位式葡萄糖传感器. 在优化的实验条件下, 该传感器在葡萄糖浓度为2×10^－4～5×10^－3 mol/L范围内有线性响应, 检测下限为5×10^－5 mol/L. 另外该传感器具有较高的稳定性和良好的选择性, 抗坏血酸、尿酸和一些氨基酸未对测定产生干扰.     

基于CDIO导向的微项目驱动交叉混合教学模式——以“日化用品制造技术”教学为例

分析了传统教学模式的优缺点,运用CDIO理念导向的工程教育模式构建了融合教学目标和教学内容的微项目,教师的“教”和学生的“学”与“做”交叉混合进行,形成了一种新的积极高效的教学模式,并在“日化用品制造技术”的教学中尝试开展了这种新的教学模式。实践表明在这种新的教学模式下,学生的学习积极性得以充分调动,学习效果有一定程度的提高,该教学模式有积极的现实意义。     

基于渥拉斯顿棱镜的单路实时偏振成像系统设计

针对非实时成像中动态场景偏振探测产生的虚假偏振信息问题,充分利用渥拉斯顿棱镜的分光特性,设计了一种新型实时偏振成像系统.采用像方远心望远透镜系统、准直透镜系统并设计匹配的成像镜系统,在单探测器阵列上同时获取偏振态相互垂直的两幅偏振图像.通过全系统联动设计与优化,系统的调制传递函数在截止频率处不小于0.55,全系统弥散斑均方根半径小于5.3μm,即小于探测器像元尺寸,满足成像设计要求.仿真结果证明该成像系统可有效解决传统分振幅偏振成像系统的实时性差的不足,分孔径偏振成像系统的能量利用率和分辨率低的问题以及偏振焦平面方法中光路串扰的缺陷,应用前景广阔.     

共沉淀法制备Ag/AgCl-TiO2空心复合纳米微球及其光催化性能

通过甲基丙烯酸与苯乙烯聚合制备了表面负电性的聚苯乙烯(PSt)纳米乳胶粒. 在乙醇与水的混合溶剂中, 用硅烷偶联剂乙烯基三甲氧基硅烷对其进行表面改性后加入钛酸四丁酯、 氯化钠和硝酸银, 以PSt乳胶粒为模板采用共沉淀法制备了PSt-AgCl-TiO₂复合微球. 在180 ℃对其进行液相预处理及煅烧去除PSt模板后制备了Ag/AgCl-TiO₂空心复合粒子. 对各阶段产物的形貌、 晶体结构和比表面积等进行了表征. 结果表明, 所得产物为Ag/AgCl与锐钛矿型TiO₂复合的空心粒子, 其比表面远大于商品TiO₂(P25). 考察了Ag/AgCl-TiO₂复合粒子在紫外光与可见光下对罗丹明B(RhB)降解的催化活性. 结果表明, 在紫外光下n(Ag)/n(Ti)=0.1%的Ag/AgCl-TiO₂复合粒子活性最高, 30 min时对RhB的降解率比不含Ag/AgCl的TiO₂空心微球提高了13%; 虽然Ag/AgCl-TiO₂在可见光下的催化活性远比紫外光下低, 但与纯TiO₂空心纳米微球相比其催化活性仍明显增强. n(Ag)/n(Ti)=2.0%的Ag/AgCl-TiO₂复合粒子催化活性最高, 120 min时对RhB的降解率比不含Ag/AgCl的TiO₂空心微球提高了38%.     

Ag掺杂型空心TiO2纳米微球的制备与表征及其光催化性能

通过甲基丙烯酸与苯乙烯的乳液聚合制备了表面载有阴离子的聚苯乙烯(PSt)纳米乳胶粒. 在乙醇与水的混合溶剂中, 用硅烷偶联剂乙烯基三甲氧基硅烷对其进行表面改性. 以此乳胶粒为模板, 加入钛酸四丁酯和硝酸银制备了Ag₂O掺杂型聚苯乙烯/二氧化钛(PSt/TiO₂)复合微球. 对该微球在180 °C进行液相预处理、干燥、500 °C煅烧等步骤制备了Ag 掺杂型Ag-TiO₂复合粒子. 通过扫描电镜(SEM)、透射电镜(TEM)和X射线衍射(XRD)等手段对PSt/TiO₂复合粒子及Ag-TiO₂空心粒子的形貌及晶体结构等进行了表征. 考察了Ag-TiO₂复合粒子在紫外光(365 nm)与紫外-可见光(370-760 nm)下对罗丹明B (RhB)降解的催化活性. 结果表明, 与不含银的TiO₂空心微球相比, 在紫外光照射下, 银含量(n_Ag/n_Ti)为0.1%的Ag-TiO₂复合粒子对RhB的降解率提高了11%左右; 在紫外-可见光照射下, n_Ag/n_Ti为1.0%和2.0% 的Ag-TiO₂复合粒子对RhB的降解率提高了30%左右.     

Theoretical investigation on the chiral diamine-catalyzed epoxidation of cyclic enones: mechanism and effects of cocatalyst

The asymmetric epoxidation of 2-cyclohexen-1-one with aqueous H(2)O(2) as oxidant, 1,2-diaminocyclohexane as catalyst, and a Br?nsted acid trifluoroacetic acid (TFA) as cocatalyst has been studied by performing density functional theory calculations. It is confirmed that the catalyzed epoxidation proceeds via sequential nucleophilic addition and ring-closure processes involving a ketiminium intermediate. Four possible pathways associated with two Z isomers and two E isomers of ketiminium have been explored in detail. Our calculation indicates that these four pathways have high barriers and a small energy gap between two more favorable R and S pathways. We have analyzed the effects of the TFA anion and H(2)O on the activity and enantioselectivity of catalytic epoxidation. It is found that the TFA anion acts as a counterion to stabilize the transition states of the catalytic epoxidation by hydrogen-bond acceptance, leading to decreases in the barriers of the nucleophilic addition and ring-closure processes. The most significant decrease occurred in the ring-closure step of the Z-R-pathway, resulting in H-bond-induced enantioselectivity. Our calculations also show that water cooperates with TFA to further increase the reaction rate significantly.     

Charged Quasinormal Modes and Dynamical Property of Black Hole with Global Monopole in de Sitter Spacetime

According to the basic rules of finite difference method,we calculate massive charged scalar field quasinormal modes of Reissner-Nordström-de Sitter Black Hole with a global monopole, which shows that when electronic quantity of scalar field e is comparatively small, all the factors including angular quantum number, the mass of scalar field, the size of horizon and the breaking scale will influence the frequency spectrum of quasinormal modes. When e is more than some definite critical value, second-order transition will appear and after that the curve of frequency spectrum rises, the black hole is no longer steady, which means when e is greater than some definite critical value, the structure of black hole can be changed. While the size of angular quantum number and breaking scale will influence the happening time of second-order transition. When breaking scale is less than some definite critical value, the second-order transition can be vanished.     

凝汽器三维汽相流场与传热特性的数值预测及改善

在采用准三维数值计算方法计算与分析一台双流程凝汽器的三维汽相流动与传热特性的基础上,针对由于冷却 水温度沿流向上升引起的汽流偏斜对传热特性的不利影响,提出一种利用导流板改善流动与传热特性的措施,通过计算证 实了措施的有效性。     

基于共心球透镜的多尺度广域高分辨率计算成像系统设计

针对实时广域高分辨率成像需求,充分利用具有对称结构的多层共心球透镜视场大且各轴外视场成像效果一致性好的特点,设计基于共心球透镜的多尺度广域高分辨率计算成像系统.该系统基于计算成像原理,通过构建像差优化函数获得光学系统设计参数,结合球形分布的次级相机阵列进行全局性优化,提高系统性能的同时有效简化光学设计过程、降低系统设计难度.系统稳定性测试结果表明,该成像系统的MTF(modulation transmission function)值在截止频率处接近衍射极限,弥散斑均方根恒小于探测器像元尺寸,整机实景实时成像效果良好,无视觉可见畸变.该系统不仅有效解决了传统成像中广域和高分辨率成像矛盾的问题,而且为计算光学成像系统设计奠定了一定研究基础.