碘叶立德化学的最新进展

本文对近十年来碘叶立德化学包括碘叶立德的合成和反应的最新进展进行综述, 并展望前景。     

单个汽泡周围的电场数值研究

为明晰电场对汽—液两相系统的效应,本文针对均匀电场作用下的汽液两相流中附着于壁面的单个汽泡,建立了数学模型,考虑了汽泡的存在对电场分布的影响。通过求解电场控制方程,得到了均匀电场作用下汽泡周围及其内部的电势及电场分布的数值解。这为进一步研究 EHD 作用下的两相系统中汽泡的行为,揭示 EHD强化沸腾换热机理奠定了基础。     

N缺陷g-C3N5修饰S掺杂苝酰亚胺增强可见光自芬顿苯酚氧化耦合Cr(Ⅵ)还原

通过静电自组装制备有机复合半导体N缺陷g-C₃N₅(NVs)修饰S掺杂苝酰亚胺(S-PDI)。NVs具有丰富的活性位点,而具有氨基基团的酰胺增强了S-PDI与NVs的分子间作用力。NVs质量分数30%的30%NVs/S-PDI对Cr(Ⅵ)的还原率为79.96%,对苯酚的降解率为74.40%;30%NVs/S-PDI协同氧化苯酚与还原Cr(Ⅵ)过程中,Cr(Ⅵ)的还原率为92.83%,苯酚的降解率为93.89%,即苯酚的氧化降解促进了Cr(Ⅵ)的还原,Cr(Ⅵ)的还原增强了苯酚的氧化降解。NVs/S-PDI充分利用导带的还原性能和价带的氧化性能,实现电子空穴的空间分离,协同强化光催化过程中的氧化半反应和还原半反应,同步提升光催化氧化还原性能。同时,光照产生的电子、H₂O₂与Cr(Ⅵ)形成一个光自芬顿反应过程,进一步促进了苯酚的氧化降解与Cr(Ⅵ)的还原去除。     

不同工质中汽泡周围电场特性研究

为探明外加电场作用下,不同工质对强化沸腾换热的影响,本文采用了FC-72、R11、R113和R123四种工质,定量研究了两相系统中汽泡周围电场分布特性,探讨了工质介电常数对汽泡的作用规律．结果表明:随着工质介电常数的增加,电场非均匀性增强,电场对汽泡的作用加剧．这为不同工质对EHD沸腾强化效果不同提供了理论依据．     

A problem-solving approach to product design using decision tree induction based on intuitionistic fuzzy

Customer complaint problem is a product design used to understand customer requirements. Furthermore, product design corresponding to customer requirement does not feel adequately solved for a cause of problem. The cause of the problem affecting product design is solved to prevent customer complaint from reoccurring. However, the problems by customer may have observation uncertainty and fuzzy. Fuzzy concept considers not only the degree of membership to an accept set, but also the degree of non-membership to a rejection set. Therefore, we present a new approach for problem solving using decision tree induction based on intuitionistic fuzzy sets in this paper. Under this approach, we first develop the problem formulation for the symptoms and causes of the problem based on intuitionistic fuzzy sets. Next, we identify the cause of the problem using intuitionistic fuzzy decision tree by the problem formulation. We then provide the approach to find the optimal cause of the problem for the consideration of product design. A numerical example is used to illustrate the approach applied for product design.     

半导体超晶格系统中的磁电调控电子自旋输运研究

通过采用转移矩阵方法求解自旋电子隧穿过程,理论研究了半导体超晶格系统中电子自旋输运的磁电调控行为.结果表明：仅对超晶格系统施以磁调制,隧穿系数将出现自旋分裂,随磁场增强,电导自旋极化率变大且展宽于费米能区;若选取不变磁场情况,同时施以间隔周期电场调制,超晶格的电子极化率将有更为显著地提高.进一步发现,随电场强度的改变,电子自旋输运行为显然存在两个明显不同区域,下自旋电子将在不同调制区域表现为不同的变化趋势.然而,若对周期磁超晶格施加间隔两周期的电调制,自旋电导输运的临界行为消失,电导极化率在高能区的共振峰 关键词： 半导体超晶格 自旋输运 磁电调控     

Azobenzene Based Photo-responsive Mechanical Actuator Fabricated by Intermolecular H-bond Interaction

Photo-responsive mechanical actuator is a class of stimuli-responsive materials transferring light to mechanical energy through macroscopic transformation. To fabricate photo-responsive mechanical actuator, soft polymeric materials crosslinked with functional bridging structures are desired. Supramolecular interaction is a relatively common way to fabricate crosslinked materials due to its excellent self-assembly performance. And azobenzene and derivatives are ideal candidates of photo-responsive materials because of the unique photo-induced trans-cis isomerization. Here, a new kind of crosslinked materials based on supramolecular interaction between 4,4'-dihydroxyazobenzene and chitosan is reported. Under 355 nm irradiation, the macroscopic bending of polymeric materials occurs rapidly due to the photo-isomerization of 4,4'-dihydroxyazobenzene. Meanwhile, the photo-responsive mechanical actuator can also lift weight which is up to 200 times that of the actuator itself, and convert energy from light to mechanical work efficiently. This report suggests a new kind of photo-responsive actuator based on supramolecular interaction and may be helpful to contribute a theoretical basis to the design and synthesis of photo-responsive mechanical actuator suitable for large-scale manufacturing industrialization in future.     

N缺陷g-C3N5修饰S掺杂苝酰亚胺增强可见光自芬顿苯酚氧化耦合Cr(Ⅵ)还原

通过静电自组装制备有机复合半导体N缺陷g-C₃N₅(NVs)修饰S掺杂苝酰亚胺(S-PDI)。NVs具有丰富的活性位点,而具有氨基基团的酰胺增强了S-PDI与NVs的分子间作用力。NVs质量分数30%的30% NVs/S-PDI对Cr(Ⅵ)的还原率为79.96%,对苯酚的降解率为74.40%;30% NVs/S-PDI协同氧化苯酚与还原Cr(Ⅵ)过程中,Cr(Ⅵ)的还原率为92.83%,苯酚的降解率为93.89%,即苯酚的氧化降解促进了Cr(Ⅵ)的还原,Cr(Ⅵ)的还原增强了苯酚的氧化降解。NVs/S-PDI充分利用导带的还原性能和价带的氧化性能,实现电子空穴的空间分离,协同强化光催化过程中的氧化半反应和还原半反应,同步提升光催化氧化还原性能。同时,光照产生的电子、H₂O₂与Cr(Ⅵ)形成一个光自芬顿反应过程,进一步促进了苯酚的氧化降解与Cr(Ⅵ)的还原去除。     

非均匀高压电场强化R11池沸腾传热实验研究

利用EHD技术进行了工质R11的池内平板沸腾强化传热实验研究。在该实验中,换热面为一平板并接地作为0电极,高压电极为平行于换热面的线状电极。实验的热流密度为1~25 kw/m2,电压为0~±25 kV,得出了正、负电压下换热系数、壁面过热度、EHD强化系数和热流密度之间的变化关系,为进一步揭示EHD强化传热的机理提供了依据。     

铀材料中杂质钍的230Th/232Th比值指纹分析研究

研究了铀材料中杂质钍的230Th/232Th比值的核取证学属性,采用基于磷酸三丁酯(TBP)的铀钍分离流程制备低本底钍纯化液,通过铀外标校正钍的分馏效应,采用多接收电感耦合等离子体质谱(MC-ICP-MS)测定230 Th/232 Th比值.结果表明,230 Th/232 Th比值是具有时效性的铀材料特征指纹信息,流程...