Strongly Phosphorescent Neutral Rhenium(I) Isocyanoborato Complexes: Synthesis,Characterization, and Photophysical,Electrochemical, and Computational Studies

A new series of neutral isocyanoborato rhenium(I) diimine complexes [Re(CO)₃(N^N)(CNBR₃)], where N^N=bpy, 4,4′‐Me₂bpy, phen, 4,7‐Me₂phen, 2,9‐Me₂phen, 3,4,7,8‐Me₄phen; R=C₆F₅, C₆H₅, Cl, 4‐ClC₆H₄, 3,5‐(CF₃)₂C₆H₃, with various isocyanoborate and diimine ligands of diverse electronic and steric nature have been synthesized and characterized. The X‐ray crystal structures of six complexes have also been determined. These complexes displayed intense bluish green to yellow phosphorescence at room temperature in dichloromethane solution. The photophysical and electrochemical properties of these complexes had been investigated. To elucidate the electronic structures and transitions of these complexes, DFT and TD‐DFT calculations have been performed, which revealed that the lowest‐energy electronic transition associated with these complexes originates from a mixture of MLCT [dπ(Re)→π*(N^N)] and LLCT [π(CNBR₃)→π*(N^N)] transitions.     

双金属同构金属-有机框架材料CAU-21-Al/M的合成、 氮气吸附及复合膜性能

通过掺杂金属的方式实现了双金属同构金属-有机框架材料的制备, 采用X射线粉末衍射(PXRD)确定了多种金属在双金属CAU-21材料中的最大掺杂量, 使用扫描电子显微镜(SEM)观察了掺杂金属对材料形貌的影响. 热重分析(TGA)结果表明, CAU-21系列材料均具有较好的热稳定性. 氮气气体吸附测试及以CAU-21-Al/M为填料的混合基质膜对N₂气的渗透实验结果与掺杂金属离子尺寸大小呈相反的关系, 证实了双金属可实现对孔道结构及气体吸附性能的调控.     

Chemical Kinetics of C5F10O with Reactive ·OH Radical Induced in AOP in Gaseous and Aqueous Phases

Plasma Chemistry and Plasma Processing - C5F10O-insulated environmental-friendly power equipment has great potential to be used in the near future to reduce greenhouse effect. During maintenance,...     

Improving Catalytic Stability and Coke Resistance of Ni/Al2O3 Catalysts with Ce Promoter for Relatively Low Temperature Dry Reforming of Methane Reaction

Aseries of Ni catalysts supported on alumina with different Ce contents(1.0%-6.0%, mass fraction) was prepared by the impregnation method and used for dry reforming of methane(DRM) at a relatively low temperature of 650 ^oC. The promotion effect of Ce with different loading amounts on the physicochemical properties of the catalysts was systematically characterized by transmission electron microscopy(TEM), X-ray diffraction(XRD), N₂ adsorption-desorption, thermo elemental IRIS Intrepid inductively coupled plasma atomic emission spectrometer (ICP-AES), UV-visible diffuse reflectance spectroscopy(UV-Vis DRS), Fourier transformation infrared(FTIR) spectra, H₂-temperature programmed reduction(H₂-TPR) analysis, H₂-temperature programmed desorption(H₂-TPD), and the X-ray photoelectron spectroscopy(XPS) techniques. The results indicate that all the catalysts mainly exist in the NiAl₂O₄ phase after being calcined at 750 ^oC with small Ni particle sizes due to the strong metal-support interaction derived from the reduction of the NiAl₂O₄ phase. The Ce-promoted catalysts show better catalytic performance as well as the resistance against sintering of Ni particles and deposition of carbon compared to the Ni/Al₂O₃ catalyst. The Ni-6Ce/Al₂O₃ exhibits the best catalytic stability and coke resistance among the four catalysts studied, which is due to its small Ni nanoparticles sizes, excellent reducibility as well as high amount of active oxygen species. In a 400 h stability test for DRM reaction at 650 ^oC, Ni-6Ce/Al₂O₃ exhibits less coke deposition and small growth of Ni nanoparticles. This work provides a simple way to preparing the Ni-Ce/Al₂O₃ catalyst with enhanced catalytic performance in DRM. The Ni-6Ce/Al₂O₃ catalyst has great potential for industrial application due to its anti-sintering ability and resistance to carbon deposition.     

A strategy for the enrichment and characterization of disulfide bond-contained proteins from Chinese cobra (Naja atra) venom

A new strategy combined gold-coated magnetic nanocomposites assisted enrichment with mass spectrometry was developed for the characterization of disulfide bond-contained proteins from Chinese cobra (Naja atra) venom. In this work, core-shell nanocomposites were synthesized by the seed-mediated growth method and used for the enrichment of snake venom proteins containing disulfide bonds. A total of 3545 tryptic digested peptides derived from 96 venom proteins in Naja atra venom were identified. The venom proteins comprised 14 toxin families including three-finger toxins, phospholipase A₂, snake venom metalloproteinase, cobra venom factor, and so forth. Extra 16 venom proteins were detected exclusively in the nanocomposites set, among which 11 venom proteins were from the three-finger toxins family. In the present study, the proposed simple and efficient protocol replaced the tedious and laborious technologies commonly used for pre-separating crude snake venom, suggesting widely implementation in low-abundance or trace disulfide bond-contained proteins or peptides characterization.     

An enhanced analytical strategy integrating offline two-dimensional liquid chromatography with high-resolution accurate mass spectrometry and molecular networking: Comprehensive characterization of HuangLian JieDu Decoction as a case study

Comprehensive ingredient research is of great significance for understanding the effective material basis of herbal medicines, but due to the diversity and complexity of their phytochemicals, such research is challenging. Here, a multifaceted strategy was proposed to analyze and identify the composition of HuangLian JieDu Decoction based on offline two-dimensional liquid chromatography combined with ultraviolet detection and high-resolution mass spectrometry. Multiple components were separated by two-dimensional liquid chromatography, which consisted of hydrophilic interaction chromatography and reversed-phase liquid chromatography, and then further characterized by high-resolution mass spectrometry with a full mass spectrometry/precursor ion list/data-dependent secondary scan data acquisition method. For data processing, database screening and molecular networking were used to identify the components in HuangLian JieDu Decoction. The offline two-dimensional liquid chromatography combined with ultraviolet detection and a high-resolution mass spectrometry system showed good orthogonality of 76.35% and a high peak capacity of 5175, effectively separating multiple components. Finally, 527 compounds, including 164 alkaloids, 133 terpenoids, 88 flavonoids, 60 phenylpropanoids, 38 organic acids, and 44 other compounds, were characterized. This integrated approach is suitable for the comprehensive characterization of herbal medicines and other complex chemical systems.     

钙钛矿太阳电池综述

基于有机-无机杂化钙钛矿材料(CH₃NH₃PbX₃)制备的太阳电池效率自2009年从3.8%增长到19.6%, 因其较高的光吸收系数, 较低的成本及易于制备等优势获得了广泛关注. 钙钛矿材料不仅可以作为光吸收层, 还可用作电子和空穴传输层, 以此制备出不同结构的钙钛矿太阳电池: 介孔结构、介观超结构、平面结构、无HTM层结构和有机结构. 除此之外, 钙钛矿材料制备方法的多样性使其更具吸引力, 目前已有一步溶液法、两步连续沉积法、双源共蒸发法和溶液-气相沉积法. 本文主要介绍了钙钛矿太阳电池的发展历程、工作原理及钙钛矿薄膜的制备方法等. 详细阐述了电池每一层的具体作用和针对现有的钙钛矿结构各层材料的优化, 最后介绍了钙钛矿太阳电池所面临的问题和发展前景, 以期对钙钛矿太阳电池有进一步的了解, 为制备新型高效的钙钛矿太阳电池打下坚实的基础.     

双小凹光学成像系统设计

随着科技发展, 如何解决大视场和高分辨率之间的矛盾成为了众多科技人员的研究重心之一, 本文提出了双小凹成像系统的概念, 在传统仿真人眼的单小凹成像系统的基础上, 通过引入反射式液晶空间光调制器对光学系统进行两个视场内波像差的调制, 改善对应的像差, 从而实现了大视场内低分辨率成像的条件下, 在两个特定的视场内满足高分辨率成像, 因此可解决大视场和高分辨率的矛盾.本文通过设计一个参考波长为587 nm, 视场为60° (即± 30°),F数为F/8, 焦距为60 mm的双小凹光学成像系统, 并利用CODE V软件模拟仿真实现了5°和17°双视场高分辨率成像, 其余视场低分辨率成像, 并以32×32的采样分辨率计算了该系统的衍射效率, 验证了设计方法的科学性和准确性.     

基于电磁感应的脉冲功率发生器试验研究

为了验证基于电磁感应原理的脉冲发生器的可行性,设计了一种小型脉冲发生器试验模型。对发生器的初始磁场与磁芯转变过程进行了分析与计算,建立了发生器的等效电路模型,并结合试验测量的负载电阻电压得出发生器的感应电压。设计的发生器整体直径约70mm,长度约85mm,其中磁芯直径为25mm,长度为25mm,提供初始磁场的永磁体厚度为10mm,试验得出发生器感应电压峰值为784.5V,与理论计算结果基本吻合,验证了发生器的可行性。