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111.
Shan Jin Manman Zhou Xi Kang Xiaowu Li Wenjun Du Xiao Wei Shuang Chen Shuxin Wang Manzhou Zhu 《Angewandte Chemie (International ed. in English)》2020,59(10):3891-3895
The high‐dimensional (that is, three‐dimensional (3D)) assembly of nanomaterials is an effective means of improving their properties; however, achieving this assembly at the atomic level remains challenging. Herein, we obtained a novel nanocluster, [Au8Ag57(Dppp)4(C6H11S)32Cl2]Cl (Dppp=1,3‐bis(diphenylphosphino)propane) showing a 3D octameric assembly mode involving the kernel penetration of eight complete icosahedral Au@Ag10Au2 units for the first time. The atomically precise structure was determined by single‐crystal X‐ray diffraction, and further confirmed by thermogravimetric analysis, X‐ray photoelectron spectroscopy, and electrospray ionization mass spectrometry measurements. Furthermore, ligand‐induced transformation prompted the conversion of [Au8Ag57(Dppp)4(C6H11S)32Cl2]Cl, with complete octameric fusion into [Au8Ag55(Dppp)4(C6H11S)34][BPh4]2, with incomplete octameric fusion. These observations will hopefully facilitate further research on the assembly of M13 nanobuilding blocks. 相似文献
112.
The present research has demonstrated that selective C?S bond cleavages of dibenzothiophene and its derivatives are feasible by thia‐Baeyer–Villiger type oxidation, i. e. the oxygen insertion process within a sulfoxide‐carbon linkage, in the presence of porphyrin iron (III) and by ultraviolet irradiation originating from sunlight, high pressure Hg‐lamp or residentially germicidal ultraviolet lamp under very mild conditions. This reaction with tert‐butylhydroperoxide at 30.0 °C leads to dibenzo[1,2]oxathiin‐6‐oxide ( PBS ) in 83.2 % isolated yield or its hydrated products, 2‐(2‐hydroxyphenyl)‐benzenesulfinic derivatives ( HPBS ) in near 100 % yield based HPLC data. PBS and HPBS are a type of biological products detected on the C?S bond cleavage step through various oxidative biodesulfurization ( OBDS ) pathways, and are useful synthetic intermediates and fine chemicals. These observations may contribute on understanding delicately molecular aspect of OBDS in the photosynthesis system, expanding the C‐S cleavage chemistry of S‐heterocyclic compounds and approaching toward biomemic desulfurization with respect to converting sulfur contaminants to chemically beneficial blocks as needed and performing under the ambient conditions. 相似文献
113.
Ligilactobacillus equi is common in the horse intestine, alleviates the infection of Salmonella, and regulates intestinal flora. Despite this, there have been no genomic studies on this species. Here, we provide the genomic basis for adaptation to the intestinal habitat of this species. We sequenced the genome of L. equi IMAU81196, compared this with published genome information from three strains in NCBI, and analyzed genome characteristics, phylogenetic relationships, and functional genes. The mean genome size of L. equi strains was 2.08 ± 0.09 Mbp, and the mean GC content was 39.17% ± 0.19%. The genome size of L. equi IMAU81196 was 1.95 Mbp, and the GC content was 39.48%. The phylogenetic tree for L. equi based on 1454 core genes showed that the independent branch of strain IMAU81196 was far from the other three strains. In terms of genomic characteristics, single-nucleotide polymorphism (SNP) sites, rapid annotation using subsystem technology (RAST), carbohydrate activity enzymes (CAZy), and predictions of prophage, we showed that strain L. equi JCM 10991T and strain DSM 15833T are not equivalent strains.It is worth mentioning thatthestrain of L. equi has numerous enzymes related to cellulose degradation, and each L. equi strain investigated contained at least one protophage. We speculate that this is the reason why these strains are adapted to the intestinal environment of horses. These results provide new research directions for the future. 相似文献
114.
With the development of modern industry,global warming is becoming a challenging issue due to the emissions of large quantities of greenhouse gases,mainly carbon dioxide(CO2).The conversion of CO2to useful compounds is considered as an effective and economic way to solve such a climate problem.Metal-organic frameworks(MOFs)are an emerging class of porous crystalline materials that have shown great potential in the conversion of CO2.The advantages of MOFs in CO 2 conversion lie in their high surface areas,adjustable pore size,and high porosity.More importantly,desirable functional sites can be easily designed and precisely installed to the pore wall of target MOFs by pre-assembly and/or post-synthetic modification(PSM)ways.This review summarizes the recent advances in constructing MOF catalysts for the application in CO2conversion.We believe that the design and synthesis of MOF catalysts for CO2conversion can be a promising way to solve the“greenhouse effect”. 相似文献
115.
为了给光锥与时间延迟积分电荷耦合器件耦合监控装置提供有效的被测运动条纹,分析了传统推扫成像实验装置的不足之处,设计了电子显示目标滚屏运动装置.采用光学相机对印刷条纹静止成像,并用TDI-CCD数字相机对监视器屏幕上的运动条纹动态成像.实验结果表明,该方案解决了高分辨率的鉴别率图样无法在监视器或投影仪上精确显示的困难.与传统的实验室模拟装置相比,该方案提高了鉴别率条纹的运动稳定性,减小了条纹运动速率与TDI-CCD扫描行频间的失配误差,不仅能够对耦合过程实施监控,而且还能用于耦合系统的像质评价. 相似文献
116.
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118.
Yongjin Fang Bu Yuan Guan Deyan Luan Xiong Wen Lou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(23):7821-7825
Metal sulfides have received considerable attention for efficient sodium storage owing to their high capacity and decent redox reversibility. However, the poor rate capability and fast capacity decay greatly hinder their practical application in sodium‐ion batteries. Herein, an elegant multi‐step templating strategy has been developed to rationally synthesize hierarchical double‐shelled nanoboxes with the CoS2 nanosheet‐constructed outer shell supported on the CuS inner shell. Their structure and composition enable these hierarchical CuS@CoS2 nanoboxes to show boosted electrochemical properties with high capacity, outstanding rate capability, and long cycle life. 相似文献
119.
Ya‐Pan Wu Jun‐Wu Tian Shan Liu Bo Li Jun Zhao Lu‐Fang Ma Dong‐Sheng Li Ya‐Qian Lan Xianhui Bu 《Angewandte Chemie (International ed. in English)》2019,58(35):12185-12189
Embedding cubane [M4(OH)4] (M=Ni, Co) clusters within the matrix of metal–organic frameworks (MOFs) is a strategy to develop materials with unprecedented synergistic properties. Herein, a new material type based on the pore‐space partition of the cubic primitive minimal‐surface net (MOF‐14‐type) has been realized. CTGU‐15 made from the [Ni4(OH)4] cluster not only has very high BET surface area (3537 m2 g?1), but also exhibits bi‐microporous features with well‐defined micropores at 0.86 nm and 1.51 nm. Furthermore, CTGU‐15 is stable even under high pH (0.1 m KOH), making it well suited for methanol oxidation in basic medium. The optimal hybrid catalyst KB&CTGU‐15 (1:2) made from ketjen black (KB) and CTGU‐15 exhibits an outstanding performance with a high mass specific peak current of 527 mA mg?1 and excellent peak current density (29.8 mA cm?2) at low potential (0.6 V). The isostructural cobalt structure (CTGU‐16) has also been synthesized, further expanding the application potential of this material type. 相似文献
120.
MXenes是一类新型的二维(2D)过渡金属碳化物、氮化物或碳氮化物的总称,在物理、化学、材料科学和纳米技术领域产生了巨大的影响。MXenes材料在制备过程中,表面会生成羟基、氟等基团,表面具有亲水性和良好的可见光响应,加上其自身具有比表面积大、活性位点丰富等优点,使其成为一种新兴的光催化材料。本文主要对MXenes及其复合材料在光催化领域的最新研究进展进行总结,简要介绍了MXenes材料的合成方法及理化性质,着重介绍了MXenes及其复合材料作为光催化剂的复合方式,光催化机理等方面的内容,并逐一列举其在光催化氧化与还原反应中的重要作用,最后对MXenes及其复合物的进一步研究提出建议和展望。 相似文献