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Ytterbium triflate hydrate catalyzed Michael addition and cyclocondensation of α,β-unsaturated ketones with active methylene compounds

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Chinese Chemical Letters 2008年第9期19卷 1024-1026页

作者： zhi wei chen Yan Li Wang Ren Er chen wei Ke Su Key Laboratory of Pharmaceutical Engineering of Ministry of Education Zhejiang University of Technology PR China College of Pharmaceutical Sciences Zhejiang University of Technology Itangzhou 310014 PR China

Catalyzed by ytterbium（III） triflate hydrate [Yb（OTf）***20], the Michael addition and cyclocondensation of α,β-unsaturated ketones with active methylene compounds to afford the 1,4-adducts and benzo[b]pyran deri... 详细信息

关键词： Ytterbium(Ⅲ) triflate hydrate α,β-Unsaturated ketones Active methylene compounds Benzo[b]pyran derivatives

An efficient method for the synthesis of dialkyl chlorophosphates from trialkyl phosphites using bis(trichloromethyl)carbonate

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Chinese Chemical Letters 2008年第8期19卷 904-906页

作者： Bo Wang Chuan Ming Yu zhi wei chen wei Ke Su College of Pharmaceutical Sciences Zhejiang University of Technology Zhejiang Key Laboratory of Pharmaceutical Engineering Hangzhou 310014 China

A mild and simple method for the synthesis of dialkyl chlorophosphates is described, bis（trichloromethyl） carbonate （BTC） is used as the effective reagent for the conversion of dialkyl phosphites to their correspo... 详细信息

关键词： Bis(trichloromethyl) carbonate Dialkyl chlorophosphate Tdalkyl phosphite Synthesis

Structures of GMC W37

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Research in Astronomy and Astrophysics 2016年第4期16卷 27-36页

作者： Xiao-Liang Zhan zhi-Bo Jiang zhi-wei chen Miao-Miao Zhang Chao Song Purple Mountain Observatory & Key Laboratory for Radio Astronomy Chinese Academy of Sciences

We carried out observations toward the giant molecular cloud W 37 with the J = 1 - 0 transitions of 12CO, 13CO and C180 using the 13.7 m single-dish telescope at the Delingha station of Purple Mountain Observatory. Based on these CO lines, we calculated the column densities and cloud masses for molecular clouds with radial velocities around ＋20 km s-1. The gas mass of W 37, calculated from 13CO emission, is 1.7 × 10^5 M, above the criterion to be considered a giant molecular cloud. The dense ridge of W 37 is a dense filament, which is supercritical in terms of linear mass ratio. Dense clumps found by C180 emission are aligned along the dense ridge at regular intervals of about 2.8 pc, similar to the clump separation caused by large-scale ＇sausage instability＇. We confirm the identification of the giant molecular filament （GMF） G 18.0-16.8 and find a new giant filament, G 16.5-15.8, located ~ 0.7° to the west of G 18.0-16.8. Both GMFs are not gravitationally bound, as indicated by their low linear mass ratio （- 80 M pc-l）. We compared the gas temperature map with the dust temperature map from Herschel images, and found similar structures. The spatial distributions of class I objects and the dense clumps are reminiscent of triggered star formation occurring in the northwestern part of W 37, which is close to NGC 6611.

关键词： ISM: clouds - ISM: structure - ISM: kinematics and dynamics - ISM: individual objects(W 37 M 16)

Research on Protection Methods of Historic and Cultural Villages in Zhejiang Province

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Journal of Harbin Institute of Technology(New Series) 2014年第4期21卷 37-42页

作者： Xiu-Ping Wang Ji-Jun Ding wei-zhi chen School of Art And Design Zhejiang Sci-Tech University

By the investigation of a few historical and cultural villages in Zhejiang Province,some problems during the process of protecting these villages were found,like similar construction pattern,coarse quality of construction,etc. which caused that villages were losing their characters. For this situation,the protection method of historical cultural villages was put forward,which was that to connect excavating character of different village with maintaining spatial fabrics of historical villages,and that different classes of building should have corresponding protection approach. Some advices were proposed for repairing and promoting historic and cultural elements,natural environment,and constructing infrastructure in the village,which will provide a reference for the construction of other historical and cultural villages.

关键词： Zheiiang Province historical and cultural villages protection methods

Studies on the Interactions between Potassium oxalato-oxodiperoxovanadate and Histidine by NMR and MS

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Chinese Chemical Letters 2001年第11期12卷 987-988页

作者： Jian Liang YE Xing Wang ZHOU Zhong chen zhi wei chen Pei Qiang HUANG Department of Chemistry Xiamen UniversityXiamen 361005 Department of Biology Xiamen UniversityXiamen 361005

Multi-nuclear NMR and ESI-MS have been applied to study the interactions between oxalato-oxodiperoxovanadate and histidine in neutral solution. Coordination between the complex and histidine was monitored by V-51 NMR. A pair of new isomers produced via vanadium atom binding separately to N1 and N3 of the imidazole ring of histidine was characterized by several spectroscopic methods. Experimental results show that the structure activity relationship of peroxovanadium complexes bearing organic ligands may be related to the specific recognition between peroxovanadium and histidine residue of tyrosine phosphatase.

关键词： oxalato-oxodiperoxovanadate histidine peroxovanadium NMR ESI-MS

A regioselective synthesis of pentacyclic compounds containing coumarin,pyrrole,indene without catalysts under microwave irradiation

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Chinese Chemical Letters 2016年第10期27卷 1622-1625页

作者： zhi-wei chen Jun-Bo Hou Zhao-Ran Dai Xiao-Feng Yang Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education College of Pharmaceutical SciencesZhejiang University of Technology

A concise and efficient approach was developed for the synthesis of pentacyclic compounds containing coumarin, pyrrole, indene in a regioselective manner in good yields via the reactions of N-substituted 4- aminocouma... 详细信息

关键词： 4-Aminocoumarin Catalyst-free Ninhydrin Regioselective Annulation

Preparation of n-Atom GHZ State and Implementation of Quantum-State Transfer via Cavity Decay

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Communications in Theoretical Physics 2008年第3期49卷 655-658页

作者： chen Li-Bo DU Qian-Hua LIN Gong-wei chen zhi-Hua LIN Xiu-Min School of Physics and Optoelectronics Technology Fujian Normal University Fuzhou 350007 China

We propose schemes to prepare n-atom Greenberger-Horn-Zeilinger （GHZ） state via two-sided cavities interacting with single-photon pulses, and achieve quantum state transfer （QST） from one atom to another atom. Entanglement particle pair and the control of coupling between qu bits are of no need in the QST process. Some practical quantum noises only decrease the success probabilities of the schemes but have no influence on the fidelity of prepared state. In addition, the success probabilities of our schemes are close to unity in the ideal case.

关键词： GHZ state quantum state transfer cavity

AFGL 5157 NH_3 : a new stellar cluster in the forming process

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Research in Astronomy and Astrophysics 2013年第6期13卷 695-704页

作者： zhi-Bo Jiang zhi-wei chen Yuan Wang Ji Yang Jia-Sheng Huang Qi-Zhou Zhang Giovani Fazio Purple Mountain Observatory Chinese Academy of Sciences Key Laboratory of Radio Astronomy Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences Harvard-Smithsonian Center for Astrophysics 60 Garden Street Cambridge MA 02138 USA

We present the analysis of Spitzer/IRAC and near infrared imaging obser- vation of AFGL 5157, an active star forming region. In the IRAC images, this region shows strong emissions of polycyclic aromatic hydrocarbons in channel 4 and emis- sions of H2 in channel 2. Many of the H2 features are aligned to form jet-like struc- tures. Three bipolar jets in the NHa core region and a couple of jets northwest of the core have been identified. We identify the possible driving agents of the bipolar jets and show them to be very young. An embedded cluster has been detected in the NH3 core; many members in the cluster have spectral energy distributions that increase from JHK bands toward longer wavelengths, indicative of their early evolutionary stages. Millimeter and submillimeter continuum emissions in the NH3 core and the northwest subregion are found to coincide spatially with these presumable Class0/I sources. The existence of H2 bipolar jets and very young stellar objects suggests that star formation is continuing at the present epoch in these subregions. Combining in- formation from previous studies, we propose a sequential star formation scenario in the whole AFGL 5157 region.

关键词： ISM individual (AFGL 5157) -- ISM jets and outflows -- ISM linesand bands -- stars formation

Ir(Ⅲ)-based Ratiometric Hypoxic Probe for Cell Imaging

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Chinese Journal of Polymer Science 2023年第5期41卷 794-801,I0011页

作者： Shi-Lu Ji Hua-Min Lan Sen-Sen Zhou Xiao-Ke Zhang wei-zhi chen Xi-Qun Jiang Department of Polymer Science&Engineering College of Chemistry&Chemical EngineeringNanjing UniversityNanjing 210093China College of Science Nanjing Forestry UniversityNanjing 210037China

Two new ratiometric hypoxia probes(Ir-C343 and Ir-GFP)are synthesized by covalently incorporating florescent internal standard molecules coumarin 343(C343)and green fluorescent protein(GFP)into bis[1-(9,9-dimethyl-9H-fluoren-2-yl)-isoquinoline](succinylacetone)Ir(Ⅲ)(Ir-fliq),*** connecting with internal standard molecules,the Ir-fliq moiety still exhibits high sensitivity to oxygen concentration,while the fluorescence intensity of the internal standard remains relatively constant under different oxygen *** a result,a ratiometric response is realized that is only related to oxygen *** addition,Ir-GFP shows more promising applications in the ratiometric hypoxia imaging of cells due to its long excitation wavelength,good water solubility,high biocompatibility,and low relative fluorescence intensity compared with the phosphorescent emitter Ir-fliq.

关键词： Hypoxia probe Ratiometric probe Hypoxic response Cell imaging