Structural Engineering and Optimization of Zwitterionic Salts for Expeditious Discovery of Thermoresponsive Materials

This work reported the discovery of N-triflimide (NTf)-based zwitter-ionic liquids (ZILs) that exhibit UCST-type phase transitions in water, and their further structural optimization in fine-tuning polarity to ultimately afford newfangled thermosensitive materials carrying attractive and biocompatible T_c values that clearly demonstrated the true value of the tunability of ZIL structure. This research established that with non-aromatic, acyclic ZILs as small-molecule thermoresponsive materials, their mixing and de-mixing with water triggered by temperatures are entirely reversible.     

广义Gr(o)tzsch环函数的近似凹凸性

In this paper, the so-called approximate convexity and concavity properties of generalized Groetzsch ring function μa （r） by studying the monotonieity,convexity or concavity of certain composites of μa（r） are obtained.     

氧化镓纳米材料的制备及其在光电探测方面的应用研究进展

近年来,半导体的纳米材料凭借其奇特的介观物理特性,成为当前研究的热点,特别是纳米金属氧化物。氧化镓纳米材料具备优异的光电、气敏、耐压且低损耗等特性,为材料学、电子学和化学等多个研究领域带来了新的机遇。本文概述了氧化镓纳米结构的制备方法,并展望了其在光电探测方面的应用。     

生晒参、全须生晒参中19种有机氯残留农药的毛细管气相色谱测定

建立了生晒参、全须生晒参中19种有机氯农药残留的毛细管气相色谱分析方法。对样品中六六六的4种异构体、滴滴涕的5种异构体、四氯苯胺、六氯苯、五氯硝基苯、七氯、五氯苯胺、艾氏剂、百菌清、环氧七氯、狄氏剂及异狄氏剂共19种有机氯农药的残留量进行了测定。以石油醚-丙酮混合物作为提取剂,样品采用索氏提取,提取液用弗罗里硅土柱层析净化。采用OV-1701石英毛细管气相色谱柱分离样品,ECD检测器进行检测。在3个水平添加时的回收率(n=5)分别为75.7%~96.1%、78.8%~111.6%和81.7%~115·2%;相对标准偏差分别为2.4%~10.6%、2.1%~9.8%和1.4~10.0%。方法用于生晒参和全须生晒参样品中农药残留的测定,结果满意。     

运用Poincaré-Miranda定理数值验证变分不等式解的存在性

本文运用Poincaré-Miranda定理数值验证变分不等式问题解的存在性.证明这一新方法相对于已有的方法更具有普遍性,并通过数值例子说明本方法的高效性.     

窄线宽光纤激光器在1030 nm波段实现3 kW近衍射极限输出

基于大模场面积掺镱光纤搭建了全光纤1030 nm高功率窄线宽光纤激光主振荡功率放大系统,实现了3004 W的最高功率输出,斜率效率69.27%,是目前报道的输出功率最高的1030 nm波段近衍射极限光纤激光器。最高输出功率时,x,y方向的光束质量因子分别为1.169,1.174,3 dB光谱宽度为0.18 nm,放大自发辐射抑制比达到37 dB。     

M2B7-(M=Mg,Zn)团簇的双重芳香性促进Mg-Mg和Zn-Zn单键的形成

本文使用密度泛函理论设计了两个无需配体的具有Mg-Mg和Zn-Zn单键的团簇Mg₂B₇^-和Zn₂B₇^-. 这两种团簇的全局能量最低构型均以M₂²⁺(B₇^3-)的形式存在,其中M-M单键处于准平面六边形形状的B₇部分的上方. 化学键分析证实了这些团簇中Mg-Mg和Zn-Zn单键的存在,这些单键是在异常稳定的B₇^3-的驱动下生成的. 该B₇^3-部分同时具有σ和π双重芳香性. 计算得到Mg₂B₇^-和Zn₂B₇^-的垂直跃迁能分别为2.79 eV和2.94 eV.     

Strong Pauli paramagnetic effect in the upper critical field of KCa2Fe4As4F2

Recently, 12442 system of Fe-based superconductors has attracted considerable attention owing to its unique double-Fe As-layer structure. A steep increase in the in-plane upper critical field with cooling has been observed near the superconducting transition temperature, Tc, in KCa2Fe4As4F2 single crystals. Herein, we report a high-field investigation on upper critical field of this material over a wide temperature range, and both out-of-plane(H∥c, Hc2c) and in-plane(H∥ab, Hc2ab ) directions have been measured.A sublinear temperature-dependent behavior is observed for the out-of-plane Hc2c , whereas strong convex curvature with cooling is observed for the in-plane Hc2ab . Such behaviors could not be described by the conventional Werthamer-Helfand-Hohenberg(WHH) model. The data analysis based on the WHH model by considering the spin aspects reveals a large Maki parameter α=9,indicating that the in-plane upper critical field is affected by a very strong Pauli paramagnetic effect.