Synthesis of Dual‐Stimuli‐Responsive Microcontainers with Two Payloads in Different Storage Spaces for Preprogrammable Release

Stimuli‐responsive microcontainers have become a major topic of interest, from fundamental aspects to applications in materials science. However, microcontainers that enable the loading of multiple species and programmable release are mostly unexplored. Herein, we describe the design and synthesis of a dual‐responsive organic/inorganic hybrid microcontainer with two payloads in separate storage spaces that is formed by the rapid UV‐initiated polymerization of Pickering emulsions. The stellate mesopore silica nanoparticles with poly(N ‐isopropylacrylamide) grafted inside the mesopores were loaded with one compound (Nile red) and used as Pickering emulsifiers to stabilize oil‐in‐water droplets. Upon UV irradiation, pH‐responsive monomers were polymerized in the presence of 5(6)‐carboxyfluorescein diacetate (CFDA) to form hybrid colloidal microcontainers. The release of Nile red and CFDA could be selectively activated by changing the temperature or pH value.     

Paternò-Büchi反应的区域选择性

Paternò-Büchi(P-B)反应,即羰基-烯的[2+2]光环化加成反应,利用其特殊的区域及立体选择性可以合成一些结构精巧的取代氧杂环丁烷。随着P-B反应在有机合成中越来越广泛的应用,人们对P-B反应的区域选择性的研究也越来越深入。在P-B反应发现之初,人们一直用“最稳定的双自由基规则”解释其区域选择性,这一规则对有些体系却不适用,近年来有人开始运用“自旋化学”理论来解释区域选择性。本论文结合作者的研究工作,评述了近年来P-B反应的区域选择性的研究进展,重点阐述了反应温度、反应物的取代基对P-B反应区域选择性的影响及其规律。     

Synthesis and characterization of <Emphasis Type=Italic>S,N</Emphasis>-heteroacenes by Bischler-Napieralski reaction

Bischler-Napieralski cyclization has been successfully employed to prepare planar S,N-heteroacenes (SNHs) with the analogue structures to 1,10-phenanthroline. The opto-/electrical properties and the packing modes of these S,Nheteroacenes were examined, which were dependent on the structure of the fused groups. SNH-based copolymers with high molecular weight and good solubility in common organic solvents or water have been synthesized by Suzuki-Miyaura- Schlüter polycondensation. The photophysical property studies revealed that the copolymers may be a promising chemosensor material.     

ON THE ERROR-SUM FUNCTION OF ALTERNATING L(U)ROTH SERIES

The error-sum function of alternating Lüroth series is introduced, which, to some extent, discerns the superior or not of an expansion comparing to other expansions. Some elementary properties of this function are studied. Also, the Hausdorff dimension of graph of such function is determined.     

利用偏振度研究散射介质浓度及杂质比的数值分析

为了研究散射介质的粒子数浓度对散射光偏振度的影响以及杂质混合比与目标偏振度的关系,求解了当激光器输出波长处于近红外波段806 nm时目标的米勒矩阵及偏振度的数值解,结果表明偏振度随散射介质粒子数浓度的变化十分显著;通过建立混合目标模型,讨论了杂质比与偏振度的数值关系,并对目标的偏振度进行了归一化,而且实现了由归一化偏振度对杂质混合比的反演。本文的研究结果为利用散射光偏振度研究大气遥感提供了新的途径。     

疏松金属材料冲击温度理论分析

以热力学原理和固态物质的三项式物态方程为基础,由密实物质的冲击绝热线和热力学状态,通过等容线法推导出了疏松金属材料的冲击温度理论计算方法。以铁为例,分析了几种物理参数对该模型计算结果的影响。计算和分析结果显示,利用新模型得到的计算结果与已有实验结果吻合较好,误差均在5%以内。疏松金属材料的冲击温度受Grneisen系数、电子Grneisen系数影响不大,而密实度、冲击压力和电子比热系数则会对疏松金属材料冲击温度产生较大影响。     

等离子体效应对碳的类氢离子能级的影响

通过在狄拉克方程中考虑德拜休克尔(Debye-Hückel)屏蔽势,研究了类氢离子C5 低能级能量1s(2S1/2),2s(2S1/2),2p(2P1/2和2P3/2)随等离子体电子温度及电子密度的变化规律,计算得到类氢离子C5 能级能量及能级电离势随等离子体环境的变化关系。同时,拟合得到了基于德拜休克尔屏蔽势下相当好的束缚态能级能量随等离子体环境变化的解析公式,利用该公式得到了类氢离子C5 相应各能级发生压致电离的临界电子密度,其结果与其它文献比有很好的可比性。结果表明:束缚态能级能量随等离子体电子温度的升高而减小,随等离子体电子密度的增大而增大。能级能量百分漂移量的对数值与等离子体电子密度的对数值以及等离子体电子温度的对数值之间均呈现出近似线性关系。对计算等离子体电离态分布及光谱模拟具有一定的意义。     

New regions including eigenvalues of Toeplitz matrices

Two new eigenvalue inclusion regions for matrices with a constant main diagonal are given. We then apply these results to Toeplitz matrices, and obtain two regions including all eigenvalues of Toeplitz matrices. Furthermore, it is proved that the new regions are tighter than those in [Melman A. Ovals of Cassini for Toeplitz matrices, Linear and Multilinear Algebra. 2012;60:189–199].     

一种基于HLLC算法的Mie-Grüneisen多介质混合模型

建立一种修正的HLLC （Harten-Lax-Van Leer-Contact）格式下稳定的Mie-Grüneisen多介质混合计算模型.Mie-Grüneisen混合模型中的通量包括守恒和非守恒两个部分,原始的HLLC格式对守恒部分适用,但是原始的HLLC格式直接用于非守恒部分,很难控制住数值振荡的产生.在原始格式中,间断面的移动速度为间断网格的左侧或右侧速度,修正后替换为网格中的平均速度,经过修正后,对HLLC格式重新进行推导,并随之扩展到二维问题.数值实验表明,利用修改后的HLLC格式,Mie-Grüneisen混合模型可以取得较好的稳定性和准确性.