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Aza-Michael addition reactions between nitroolefins and benzotriazole catalyzed by MCM-41 immobilized heteropoly acids in water

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Chinese Chemical Letters 2013年第1期24卷 28-30页

作者： Shao-Lei xie Yong-Hai Hui Xiang-Ju Long Chang-Chun Wang zheng-feng xie Key Laboratory of Oil & Gas Fine Chemicals Ministry of Education & Xinjiang Uyghur Autonomous RegionCollege of Chemistry and Chemical EngineeringXinjiang University

MCM-41 supported heteropoly acids （HPAs） catalysts were synthesized, characterized and their catalytic activity was evaluated in an aza-Michael addition reaction between nitroolefins and benzotriazole in water at room temperature. 50 wt% PW/MCM-41 showed the highest activity （up to 96% yield）. The catalyst was used in six consecutive experiments without obvious loss of activity, confirming the success of the anchoring process and the catalyst stability.

关键词： Aza-Michael additionMCM-41Heteropoly acidsHeterogenous catalysts

Convenient synthesis of bis(indolyl)alkanes by dithiocarbohydrazone Schiff base/Zn(ClO_4 )_2 6H_2 O catalyzed Friedel–Crafts reaction of indoles with imines

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Chinese Chemical Letters 2014年第1期25卷 163-165页

作者： Yong-Hai Hui Yong-Cheng Chen Hai-Wei Gong zheng-feng xie Key Laboratory of Oil & Gas Fine Chemicals Ministry of Education & Xinjiang Uyghur Autonomous RegionCollege of Chemistry and Chemical EngineeringXinjiang University

A new, convenient and excellent yield procedure for the preparation of bis（indolyl）methanes （BIMs） by Friedel-Crafts reaction of indoles with imines in the presence of dithiocarbohydrazone Schiff base/ Zn（CIO4）2.6H2O as a highly stable, effective and readily available catalyst is described. Moderate to good yields （up to 99% yield） were obtained with both substrates for imine derivatives. This procedure is simple, practical and economic.

关键词： Friedel-Crafts reaction Indoles Imines BIMs

Friedel-Crafts alkylation of indoles with nitroalkenes catalyzed by Cu(Ⅱ)-imine complex

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Chinese Chemical Letters 2011年第10期22卷 1155-1158页

作者： Ning Ning Wan Yong Lei Yang Wen Ping Wang zheng feng xie Ji De Wang College of Chemistry and Chemical Engineering Xinjiang University Urumqi 830046 China Key Laboratory of Oil ＆ Gas Fine Chemicals of Ministry of Education Xinjiang University Urumqi 830046 China

A series of new ligands L_1-L_7 were readily prepared in one ***-Crafts alkylation of indoles with nitroalkenes catalyzed by a novel Cu（Ⅱ）-L complex has been *** remarkable advantages of this reaction are mild reac... 详细信息

关键词： Friedel-Crafts alkylation Indole Nitroalkene Copper Imine

Synthesis of bis(indolyl) methanes catalyzed by Schiff base-Cu(Ⅱ) complex

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Chinese Chemical Letters 2011年第9期22卷 1071-1074页

作者： Yong Lei Yang Ning Ning Wan Wen Ping Wang zheng feng xie Ji De Wang College of Chemistry and Chemical Engineering Xinjiang University Urumqi 830046 China Key Laboratory of Oil & Gas Fine Chemicals of Education of Ministry Xinjiang University Urumqi 830046 China

Schiff base-Cu（II） complex is found to be an effective catalyst for the condensation reaction of indole with aldehydes using ethanol as the solvent. The characterization of the catalysts was carried out using XRD an... 详细信息

关键词： Schiff base complex Bis(indolyl) methanes Indole Aldehydes

Contributors to tidal duration asymmetry with varied coastline configurations on western shelf of Yellow Sea

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Water Science and Engineering 2024年第1期17卷 1-12页

作者： Xi feng zheng Li Hui feng Jia-yan Yang Shou-peng xie Wei-bing feng College of Harbor.Coastal and Offshore Engineering Hohai UniversityNanjing 210098China China Harbour Engineering Co. LtdBeijing 100027China Key Laboratory of Port Waterway and Sedimentation Engineering of the Ministry of CommunicationsNanjing 210029China China South-to-North Water Diversion Corporation Limited Beijing 100036China

Coastal management in China is confronted with an urgent choice between natural restoration and maintenance of existing seawalls and reclaimed land for economic development.A key criterion for making this decision is the resilience to coastal flooding,which depends on the ability to predict tidal *** duration asymmetry(TDA)is a key parameter in determination of the arrival and duration of flood *** study selected the western inner shelf of the Yellow Sea(WYS)as the study area and investigated the responses of TDA to different shoreline configurations and relative sea level *** responses of TDA to shoreline reconstruction yielded spatial variability locally and *** the nearshore area,the responses of TDA to the complex ocean environment mainly originated from the combined functions of reflection,bottom friction,and advection,which controlled the energy transfer from M2 or S2 constituents to their overtides or compound *** sensitivity of TDA to coastline typologies was not limited to coastal waters but could stretch over the entire inner *** vulnerability of tidal responses was due to the displacement of the M2 amphidrome of the Kelvin wave on the WYS,which in turn changed tidal energy fluxes over the *** relative sea level rise could intensify the feedback of TDA to seawalls and land reclamation.

关键词： Tidal duration asymmetry Western inner shelf of Yellow Sea Natural restoration Relative sea level rise Tidal amphidrome

Mn(OAc)_2/Schiff base as a new efficient catalyst system for the Henry reaction of nitroalkanes with aldehydes

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Chinese Chemical Letters 2012年第6期23卷 690-694页

作者： Guang Peng Zhou Yong Hai Hui Ning Ning Wan Qiu Ju Liu zheng feng xie Ji De Wang Key Laboratory of Oil and Gas Fine Chemicals Ministry of Education and Xinjiang Uyghur Autonomous RegionCollege of Chemistry and Chemical Engineering Xinfiang University Urumqi 830046 China

A series of novel Schiff bases bearing triazole structure were synthesized and characterized by LR and NMR. Mn（OAc）2/Schiff base efficiently catalyzed Henry reaction of nitroalkanes with aldehydes to produce the corresponding products of ^-nitroalcohols, under mild conditions with high yields （up to 99%）. A reaction mechanism is proposed based on the experimental results.

关键词： Schiff base Henry reaction Aldehydes Nitroalkanes

Turbulence Statistics of Thermo-Buoyancy Supercritical Fuel Flow in a Regenerative Cooling Channel

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Journal of Thermal Science 2024年第1期33卷 126-137页

作者： SUN feng xie Gongnan School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072China Department of Thermal Engineering Tsinghua UniversityBeijing 100084China

Active regenerative cooling with supercritical hydrocarbon fuel is considered as the most promising thermal protection *** existence of buoyancy force would lead to strongly anisotropic flow and thermal transport *** is closely related to the cooling performance of the *** elucidate the mechanisms of turbulent transport,the large eddy simulation(LES) was performed to assess turbulence statistics within different turbulence *** results indicated that the buoyancy and inertial force together dominated the change of turbulent ***,the spatial thermal buoyancy effect significantly suppressed the vertical velocity *** is due to the laminar motion caused by the buoyancy force,thereby weakening the thermal *** the statistics of velocity fluctuation,it was found that the buoyancy force and inertial force greatly weaken the vertical and streamwise velocity fluctuation,*** the statistics of thermal transport,the results pointed out that the near-wall heat transport characteristics need to be paid more *** thickness of the temperature mixing boundary layer led to the attenuation of vertical heat flux,which inhibited vertical temperature diffusion and predisposed to extreme conditions of heat transfer *** results can enhance the academic understanding of the heat transfer mechanism of supercritical fluids,and give guidance for further applications of thermal protection.

关键词： active regenerative cooling large eddy simulation(LES) buoyancy force turbulence statistics

Catalyst-free and Reprocessable Aromatic Polydithiourethanes

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Chinese Journal of Polymer Science 2024年第10期42卷 1435-1441,I0007页

作者： Bo Yang Hai-Jun feng Tian-Tian Ni Xiao-Rui Zhou Tao xie Ning zheng State Key Laboratory of Chemical Engineering College of Chemical and Biological EngineeringZhejiang UniversityHangzhou310058China Department of Colorectal Surgery and Oncology Key Laboratory of Cancer Prevention and InterventionMinistry of EducationThe Second Affiliated HospitalZhejiang University School of MedicineHangzhou310009China

The incorporation of dynamic covalent bonds into thermosets facilitates the reprocessing of polymer networks,thereby meeting the sustainable requirements for polymer ***,the mechanical properties of many materials often decline significantly upon reprocessing due to side reactions caused by harsh processing *** this work,we find that the aromatic dithiocarbamate bond can undergo dissociation under mild conditions without the need for a catalyst,enabling the efficient reprocessing of the corresponding *** a consequence,the mechanical properties of the polydithiourethane can be largely preserved after *** discovery of this dynamic chemistry is anticipated to broaden the potential for material design in dynamic covalent polymer networks.

关键词： Reprocessing Polydithiourethane Dynamic covalent bond

Deep Industrial Image Anomaly Detection: A Survey

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Machine Intelligence Research 2024年第1期21卷 104-135页

作者： Jiaqi Liu Guoyang xie Jinbao Wang Shangnian Li Chengjie Wang feng zheng Yaochu Jin Research Institute of Trustworthy Autonomous Systems Southern University of Science and TechnologyShenzhen 518055China NICEGroup Universityof SurreyGuildford GU27YXUK Youtu Lab TencentShanghai 200233China NICE Group Bielefeld UniversityBielefeld 33619Germany

The recent rapid development of deep learning has laid a milestone in industrial image anomaly detection(IAD).In this pa-per,we provide a comprehensive review of deep learning-based image anomaly detection techniques,from the perspectives of neural net-work architectures,levels of supervision,loss functions,metrics and *** addition,we extract the promising setting from indus-trial manufacturing and review the current IAD approaches under our proposed ***,we highlight several opening chal-lenges for image anomaly *** merits and downsides of representative network architectures under varying supervision are ***,we summarize the research findings and point out future research *** resources are available at https://***/M-3LAB/awesome-industrial-anomaly-detection.

关键词： Image anomaly detection defect detection industrial manufacturing deep learning computer vision