A Novel Ternary Composite of Polyurethane/Polyaniline/Nanosilica with Antistatic Property and Excellent Mechanical Strength: Preparation and Mechanism

Chinese Journal of Polymer Science - Antistatic and strength properties are of vital importance for polyurethane rubber used in moving parts of many industrial instruments. Herein, polyurethane was...     

Formation of Azulene-Embedded Nanographene: Naphthalene to Azulene Rearrangement During the Scholl Reaction

Incorporation of a non-hexagonal ring into a nanographene framework can lead to new electronic properties. During the attempted synthesis of naphthalene-bridged double [6]helicene and heptagon-containing nanographene by the Scholl reaction, an unexpected azulene-embedded nanographene and its triflyloxylated product were obtained, as confirmed by X-ray crystallographic analysis and 2D NMR spectroscopy. A 5/7/7/5 ring-fused substructure containing two formal azulene units is formed, but only one of them shows an azulene-like electronic structure. The formation of this unique structure is explained by arenium ion mediated 1,2-phenyl migration and a naphthalene to azulene rearrangement reaction according to an in-silico study. This report represents the first experimental example of the thermodynamically unfavorable naphthalene to azulene rearrangement and may lead to new azulene-based molecular materials.     

Lipase‐Supported Metal–Organic Framework Bioreactor Catalyzes Warfarin Synthesis

A green and sustainable strategy synthesizes clinical medicine warfarin anticoagulant by using lipase‐supported metal–organic framework (MOF) bioreactors (see scheme). These findings may be beneficial for future studies in the industrial production of chemical, pharmaceutical, and agrochemical precursors.     

Planar AIEgens with Enhanced Solid-State Luminescence and ROS Generation for Multidrug-Resistant Bacteria Treatment

Planar luminogens have encountered difficulties in overcoming intrinsic aggregation-caused emission quenching by intermolecular π-π stacking interactions. Although excited-state double-bond reorganization (ESDBR) can guide us on designing planar aggregation-induced emission (AIE) luminogens (AIEgens), its mechanism has yet been elucidated. Major challenges in the field include methods to efficiently restrict ESDBR and enhance AIE performance without using bulky substituents (e.g., tetraphenylethylene and triphenylamine). In this study, we rationally developed fluoro-substituent AIEgens with stronger intermolecular H-bonding interaction for restricted molecular motions and increased crystal density, leading to decreased nonradiative decay rate by one order of magnitude. The adjusted ESDBR properties also show a corresponding response to variation in viscosity. Furthermore, their aggregation-induced reactive oxygen species (ROS) generations have been discovered. The application of such planar AIEgen in treating multidrug-resistant bacteria has been demonstrated in a mouse model. The relationship between ROS generation and distinct E/Z-configurational stacking behaviors have been further understood, providing a design principle for synthesizing planar AIEgen-based photosensitizers.     

Fréchet空间上的一些等距逼近问题

本文主要讨论Ｆｒéｃｈｅｔ空间上ε－等距线性算子的等距逼近问题，证明了任意有限维Ｆｒéｃｈｅｔ空间之间的等距逼近问题都是肯定的；无穷维Ｆｒéｃｈｅｔ空间（ｓ）空间上的等距逼近问题也是肯定的．     

油水两液相一维非等温渗流的传递分析

在求解油水两液相非等温渗流的温度场、压力场基础上,以驱动功、驱动功率、驱动阻力、驱动速率为特征参数,对该过程进行(火用)传递分析。数值模拟的结果表明:含水通过降低油的相对渗透率、从而增大驱动阻力、减小驱动功率, 最终导致原油产量降低。     

1+1/2对转涡轮叶排轴向间距对性能影响的研究

木文对1+1/2对转涡轮中轴向间距影响进行了初步研究。对不同轴向间距叶栅流场进行了大量时间精确模拟。研究表明,1+1/2对转涡轮高低压转叶间轴向间距成为追求高效率的制约因素,轴向间距为高压转叶喉部宽度是关键点。因此有关小轴向间距下强激波/叶排干扰的研究应该加强。     

As+注入硅的紫外-可见椭圆偏振光谱

本文采用椭圆偏振光谱法研究了剂量为1×10¹⁶—3×10¹²cm^-2的As⁺注入硅,及其在700℃退火后的光学性质。得出:当As⁺注入剂量增大到某一程度后,便呈非晶特性。低于临界剂量的样品,其n-λ,ε₂-λ关系曲线随剂量的增大而往下方移动,呈有规律变化;退火后,在大于4000?波段,n-λ与ε₂-λ曲线基本恢复到单晶硅状态。但在小于4000?的紫外区却未完全恢复,注入剂量越大,偏离单晶硅就越大。并指出,紫外光区是离子注入硅的信息敏感区;用有效质量模型计算出注入剂量与损伤度的关系。计算结果与实验符合得较好。 关键词：     

光纤的能量传输特性及应用

着重分析了影响光纤传输能量以及光纤传输中造成能量损耗的因素。这些因素主要包括光纤材料、构造、光纤的折射率分布、光纤的长度和芯径、光纤的数值孔径和热效应以及耦合等。同时 ,结合激光二极管点火的实例 ,分析探讨了其背景和应用价值。结论是 :为了尽可能减少能量损耗、提高光纤输出的激光功率和激光功率密度 ,应当选取合适的激光工作波长、较小的光纤长度、较小的芯径和较小的数值孔径 ,应采用渐变折射率分布光纤 ,应减少弯曲与耦合