检索结果-南通市图书馆

Electrochemical construction of 2,5-diaryloxazoles via n–H and C(sp_(3))-H functionalization

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第4期35卷 340-345页

作者： Tong li Leping Pan Yan Zhang Jihu Su Kai li Kuiliang li Hu Chen Qi Sun Zhiyong Wang Hefei national Center for Physical Sciences at Microscale Key Laboratory of Precision and Intelligent ChemistrySchool of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China Anhui University of Science and Technology Huainan 232001China CAS Key Laboratory of Microscale Magnetic Resonance Department of Modern PhysicsUniversity of Science and Technology of ChinaHefei 230026China

An efficient n–H and C(sp~3)-H functionalization of aryl ketones with benzylamines/amino acids was developed under mild conditions by virtue of anodic oxidation. A variety of functionalized 2,5-diaryloxazoles were obtained with good to excellent yields. Moreover, some important natural products can be prepared by this method. The reaction features a broad substrate scope, scalability, metal-free and chemical oxidant-free.

关键词： Electrochemical Metal-free Oxazole Oxidant-free

Effect of Mn content on microstructure and properties of AlCrCuFeMnx high-entropy alloy

在线全文

学校读者我要写书评

暂无评论

China Foundry 2024年第2期21卷 147-158页

作者： ning Wang Kai Ma Qiu-da li Yu-dong Yuan Yan-chun Zhao li Feng School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China State Key Laboratory of Advanced Processing and Reuse of nonferrous Metals Lanzhou 730050China CnnC nuclear Power Operation and Management Co. Ltd.Haiyan 314300ZhejiangChina

AlCrCuFeMnx(x=0,0.5,1,1.5,and 2)high-entropy alloys were prepared using the vacuum arc melting *** microstructure and mechanical properties of AlCrCuFeMnxwere analyzed and tested by XRD,SEM,TEM,nanoindentation,and electronic universal *** results indicate that the AlCrCuFeMnxhigh-entropy alloy exhibits a dendritic structure,consisting of dendrites with a BCC structure,interdendrite regions with an FCC structure,and precipitates with an ordered BCC structure that form within the ***(Mn)has a strong affinity for dendritic,interdendritic,and precipitate structures,allowing it to easily enter these *** an increase in Mn content,the size of the precipitated nanoparticles in the dendritic region initially increases and then ***,the area fraction initially decreases and then ***,the alloy’s strength and wear resistance decrease,while its plasticity *** Al Cr Cu Fe Mn1.5alloy boasts excellent mechanical properties,including a hardness of 360 HV and a wear rate of 2.4×10^(-5)mm^(3)·n^(-1)·mm^(-1).It also exhibits impressive yield strength,compressive strength,and deformation rates of 960 MPa,1,700 MPa,and 27.5%,respectively.

关键词： high-entropy alloys microstructure mechanical properties wear resistance strengthening mechanisms

BaCe_(0.8)Fe_(0.1)ni_(0.1)O_(3−δ)-impregnated ni-GDC by phase-inversion as an anode of solid oxide fuel cells with on-cell dry methane reforming

在线全文

学校读者我要写书评

暂无评论

Journal of Advanced Ceramics 2024年第6期13卷 834-841页

作者： Yanya liu Jun Luo Cheng li Bo liu Dong Yan Jian li lichao Jia School of Materials Science and Engineering State Key Laboratory of Materials Processing and Die&Mould TechnologyHuazhong University of Science and TechnologyWuhan 430074China

BaCe_(0.8)Fe_(0.1)ni_(0.1)O_(3−δ)(BCFn)in a perovskite structure is impregnated consecutively by BCFn solution and BCFn suspension into a phase-inversion prepared niO–Gd_(0.1)Ce_(0.9)O_(2−δ)(GDC)scaffold as an anode for solid oxide fuel cells(SOFCs)with on-cell dry reforming of methane(DRM).The whole pore surface of the scaffold is covered by small BCFn particles formed by BCFn solution impregnation;the large pores near the scaffold surface are filled by BCFn aerogels with a high specific surface area produced by BCFn suspension impregnation,which act as a catalytic layer for on-cell *** reduction,the anode consists of a ni–GDC scaffold and BCFn particles with exsolved Feni3 *** BCFn-impregnated ni–GDC anode has higher electrical conductivity,electrochemical activity,and resistance to carbon deposition,with which the cell shows maximum power densities between 1.44 and 0.92 W·cm^(−2) when using H_(2) and between 1.09 and 0.50 W·cm^(−2) when using CO_(2)–CH_(4) at temperatures ranging from 750 to 600℃.A stable performance at 400 mA·cm^(−2) and 700℃is achieved using 45%CO_(2)–45%CH_(4)–10%n_(2) for more than 400 h without carbon deposition,benefiting from the impregnated BCFn aerogel with a high specific surface area and water adsorbability.

关键词： aerogel solid oxide fuel cells(SOFCs) phase-inversion dry reforming of methane(DRM) carbon resistance

Tongqiao Yizhi granule(通窍益智颗粒) repress the nuclear factor kappa-b/nucleotide oligomerization domain-like receptors 3/caspase-1 pyroptosis pathway in the hippocampus to counter vascular dementia in rats

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Traditional Chinese Medicine 2024年第4期44卷 680-687页

作者： li Yanjiao HAO linyao li Shuangyang LUO Yanqi WAnG Juan WAnG Raoqiong BAI Xue College of Integrative Medicine Southwest Medical University Department of neurology and national Traditional Chinese Medicine Clinical Research Base the Affiliated Traditional Chinese Medicine Hospital of Southwest Medical University Institute of Integrated Chinese and Western Medicine Southwest Medical University

OBJECTIVE: To explore the mechanism by which Tongqiao Yizhi granule（通窍益智颗粒, TQYZKL） intervenes pyroptosis to treat vascular dementia（VaD） in a rat model. METHODS: The rat model of VaD was established by two-vessel occlusion（2VO）. The rats were randomly divided into Sham group, Model group, nimodipine group, TQYZKL（6.2 g·kg-1·d-1）, TQYZKL(12.4 g·kg-1·d-1), TQYZKL(24.8 g·kg-1·d-1). The Morris water maze（MWM） test was carried out to test the learning and memory function; Hematoxylin-eosin staining and transmission electron microscopy（TEM） to observe the pathological damage in the hippocampus; Tunel fluorescence staining to detect neuronal pyroptosis in the hippocampus. The expression levels of pyroptosis-related proteins, namely Golgi peripheral membrane protein p65（P65）, nucleotide oligomerization domain-like receptors 3（nLRP3）, caspase-1 and Gasdermin D（GSDMD）, were detected using Western blotting and reverse transcription polymerase chain reaction. Moreover, the serum levels of interleukin-1β（IL-1β） and interleukin-18（IL-18） were determined through the enzyme-linked immunosorbent assay. RESULTS: The study revealed that TQYZKL effectively improved the ability of VaD ratsto learn and memorize, relieved the pathological damage in the hippocampus, restored neuronal morphology, and reduced the expression of pyroptosis-related proteins P65, nLRP3, caspase-1, GSDMD-n, IL-18 and IL-1β（P nCLUSIOn: TQYZKL inhibits neuronal pyroptosis in the hippocampus of VaD rats by regulating nuclear factor kappa-B/nLRP3/caspase-1 signaling pathway, thus exerting a therapeutic effect on VaD in the rats.

关键词： nF-kappa B nLR family, pyrin domain-containing 3 protein Tongqiao Yizhi granule caspase 1 dementia, vascular pyroptosis

同方期刊数据库

Synthesis of crystalline g-C_(3)n_(4) with rock/molten salts for efficient photocatalysis and piezocatalysis

在线全文

学校读者我要写书评

暂无评论

Green Energy & Environment 2024年第5期9卷 890-898页

作者： Tingting Xu Jung Hur Ping niu Shulan Wang Sangwook Lee Sang-Eun Chun li li Department of Chemistry College of ScienceNortheastern UniversityShenyang110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819China School of Metallurgy Northeastern UniversityShenyang110819China School of Materials Science and Engineering Kyungpook National UniversityDaegu41566Republic of Korea School of Industrial Technology Advances Kyungpook National UniversityDaegu41566Republic of Korea

Graphitic carbon nitride(g-C_(3)n_(4))is emerging as a promising visible-light photocatalyst while the low crystallinity with sluggish charge separation/migration dynamics signiﬁcantly restricts its practical ***,synthesizing highly crystalline g-C_(3)n_(4) with sufﬁcient surface activities still remains ***,different from using alkali molten salts which is commonly reported,we propose an approach for synthesis of highly crystalline g-C_(3)n_(4) with FeCl3/KCl rock/molten mixed *** rock salt can serve as the structure-directing template while molten salt provides the required liquid medium for ***,the synthesized photocatalyst showed further enhanced crystallinity and improved surface area along with high p/p*excitation compared with crystalline C_(3)n_(4) prepared from conventional molten-salt *** catalytically advantageous features lead to its superior photocatalytic and piezocatalytic activities with a high reactivity for overall water splitting that is not commonly reported for C_(3)n_(4).This work provides an effective strategy for structural optimization of organic semiconductor based materials and may inspire new ideas for the design of advanced photocatalysts.

关键词： High crystallinity Carbon nitride Photocatalysis Piezocatalysis Overall water splitting

Efficient guiding and focusing of intense laser pulse using periodic thin slits

在线全文

学校读者我要写书评

暂无评论

Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu T.W.Huang K.Jiang C.n.Wu H.Peng P.C.hen R.li H.B.Zhuo C.T.Zhou Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material Technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction with thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse with periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared with conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

Constrained docking control for shipborne UAV SideArm recovery

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第5期37卷 39-59页

作者： Zikang SU Zhuolin XInG Xuebing li Chuntao li Xinwei WAnG Honglun WAnG College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Engineering and Materials Science Queen Mary University of LondonLondon E14NSUK School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

In this work,we sought to investigate constrained docking control during shipborne SideArm recovery of an Unmanned Aerial Vehicle(UAV)under preassigned safe docking constraints,rough ocean environments,and different initial *** aim was to solve the UAV tracking-lag problem that manifests when attempting to dock with a rapidly moving SideArm and to improve the accuracy and rapidity of ***,together with the formulations of the shipborne SideArm system and environmental airflows,the affine nonlinear dynamics of the hook was established to reduce tracking ***,echo state network approximators with good approximation capacity and low computational consumption were designed to accurately approximate the UAV’s unknown nonlinear *** feedforward compensation provided by these approximators,a nonlinear-mapping-based constrained docking control law was developed for shipborne SideArm recovery of *** approach to controlling the docking trajectory and the forward docking speed of the UAV can achieve rapid and exact docking with a moving SideArm,without violating the preassigned safe docking-constraint *** under different docking scenarios were used to validate the effectiveness and advantages of the proposed docking-control algorithm.

关键词： SideArm recovery Unmanned aerial vehicle Docking control nonlinear mapping Echo state network

Single-atom catalysis:a promising avenue for precisely controlling reaction pathways

在线全文

学校读者我要写书评

暂无评论

Frontiers of Chemical Science and Engineering 2024年第7期18卷 97-120页

作者： Xiaobo Yang Xuning li Yanqiang Huang State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Single-atom catalysts (SACs), characterized by exceptionally high atom efficiency, have garnered significant attention across various catalytic reactions. Recent studies have showcased SACs with robust capabilities for precise catalysis, specifically targeting reactions along designated pathways. This review focuses on the advances in the precise activation and reconstruction of chemical bonds on SACs, including precise activation of C–O and C–H bonds and selective couplings involving C–C and C–n bonds. Our discussion begins with a thorough exploration of the factors that render SACs skilled in precise catalytic processes, encompassing the narrow d-band electronic state of single atom site resulting in the adsorption tendency, isolate site resulting in unique adsorption structure, and synergy effect of a single atom site with its neighbors. Subsequently, we elaborate on the applications of SACs in electrocatalysis and thermocatalysis including four prominent reactions, namely, electrochemical CO_(2) reduction, urea electrochemical synthesis, CO_(2) hydrogenation, and CH4 activation. Then the concept of rational design of SACs for precisely controlling reaction pathways is discussed from the aspects of pore structure design, support-metal strong interaction, and support hydrophilic/hydrophobic. Finally, we summarize the challenges encountered by SACs in the field of precise catalytic processes and outline prospects for their further development in this domain.

关键词： single atom catalysts selective oxidation CO2RR bond coupling

Rapid and chemoselective imidation of sulfides in aqueous buffer enabled by a novel guanidine-derived n-O reagent

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第6期67卷 1929-1934页

作者： Hanzheng li Long Xu Jiajia Dong Key Laboratory of Organofluorine Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai200032China Institute of Translational Medicine National Facility for Translational Medicine(Shanghai)Shanghai Jiao Tong UniversityShanghai200240China School of Chemistry and Chemical Engineering Zhangjiang Institute for Advanced StudyShanghai Jiao Tong UniversityShanghai200240China Shanghai Artificial Intelligence Laboratory Shanghai200232China

Herein we report the facile synthesis of a series of novel n-O reagents and identify n′-di-Boc-n′′-[(mesitylsulfonyl)oxy]-guanidine as an efficient imidating *** reagent is synthetically scalable and bench-stable,yet it shows unprecedented reactivity and chemoselectivity towards S(II)in buffer/hexafluoroisopropanol(HFIP)system,to generate a new class of nguanyl *** transformation of n-guanyl sulfilimines to n-guanyl sulfoximines provides us a chance to investigate these rarely reached compounds,which are shown to be versatile precursors to a variety of n-heterocyclic and *** work provides an addition to the tool box of both sulfur imidation and guanidine synthesis,especially for the need of rapid and selective modifications of sulfur(II)center under biocompatible conditions.

关键词： sulfur imidation n-O reagent

同方期刊数据库