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CONTROLLED/"living" RADICAL polymerization OF STYRENE IN AN AQUEOUS DISPERSION SYSTEM

Chinese Journal of Polymer science 2002年第5期20卷 445-451页

作者： Bin Zhang Zhao-bin Zhang Xiao-long Wan Chun-pu Hu sheng-kang ying lab of living polymerization, east china university of science and technology.shanghai 200237,china E china Univ Sci & Technol Lab Living Polymerizat Shanghai 200237 Peoples R China

Atom transfer radical polymerization (ATRP) of styrene catalyzed by cuprous (CuX)/1,10-phenanthroline (Phen) and CuX/CuX2/Phen was conducted in an aqueous dispersed system. A stable latex was obtained by using ionic surfactant sodium lauryl sulfonate (SLS) or composite surfactants, such as SLS/polyoxyethylene nonyl phenyl ether (OP-10), SLS/hexadecanol and SLS/OP-10/hexadecanol, Among which SLS and SLS/OP-10/hexadecanol systems established better dispersed effect during the polymerization, It was found that Phen was a more suitable ligand than N,N,N',N',N'-pentamethyldiethylenetriamine (PMDETA) to maintain an appropriate equilibrium of the activator Cu(I) and the deactivator Cu(II) between the organic phase and the water phase, The effect of several initiators (such as EBiB, CCl4 and 1-PEBr) and the temperature on such a kind of ATRP system was also observed. The number-average molar mass (M-n) of polystyrene (PS) increased with the conversion and the molar mass distribution (M-w/M-n) remained narrow. These experimental data show that the polymerization could be controlled except for the quick increase of monomer conversion and the number-average molar mass of PS in the initial stage of polymerization. Furthermore, the initiator efficiency was found to be low (similar to57%) in CuX/Phen catalyzed system. To overcome this problem, Cu(II)X-2 (20 mol%-50 mol% based on CuX) was introduced into the polymerization system. In this case, higher initiator efficiency (60%-90%), low M-w/M-n of PS (as low as 1.08) were achieved and the molar masses of the PS fit with the theoretical ones.

关键词： controlled/'living' radical polymerization polystyrene water dispersed polymerization 1,10-Phenanthroline

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SYNTHESIS OF BLOCK COPOLYMER BY INTEGRATED living ANIONIC polymerization-ATOM TRANSFER RADICAL polymerization(ATRP)

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Chinese Journal of Polymer science 2000年第1期18卷 39-43页

作者： Bing Liu Feng Liu Ning Luo sheng-kang ying Qing Liu laboratory of living polymerization, east china university of science and technology, shanghai 200237, china Research Institute of Beijing Yanshan Petrochemical Corporation, Beijing 102549, china E china Univ Sci & Technol Lab Living Polymerizat Shanghai 200237 Peoples R China Beijing Yanshan Petrochem Corp Res Inst Beijing 102549 Peoples R China

Alpha-trichloroacetoxy terminated polystyrene oligomer (PS-CH2CH2OCOCCl3) and poly-(styrene-b-butadiene) oligomer [P(S-b-B)-CH2CH2OCOCCl3)] were synthesized by living anionic polymeri-zation using n-butyllithium as initiator. Then the PS-CH2CH2OCOCCl3 (PS-Cl-3) or P(S-b-B)-CH2CH2O-COCCl3 (PSB-Cl-3) was used as the macroinitiator in the polymerization of(meth)acrylates in the presence of CuX/bpy. AB diblock and ABC triblock copolymers were prepared by the integrated living anionic polymerization (LAP)-atom transfer radical polymerization (ATRP). The structures of the PSB-Cl-3 and the P(S-b-MMA) were identified by FTIR and H-1-NMR spectrum, respectively. A new way to design block copolymers (the combination of LAP and ATRP) was developed.

关键词： living anionic polymerization atom transfer radical polymerization block copolymer

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Synthesis of α-Bromine-Terminated Polystyrene Macroinitiator and Its Initiation of MMA polymerization by ATRP

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Chemical Research in Chinese Universities 2000年第1期16卷 72-77页

作者： LIU Feng LIU Bing LUO Ning and ying shengkang (The laboratoric of living polymerization, east china university of science and technology, shanghai 200237, P. R. china) LIU Qing (Research Institute of Beijing Yanshan Petrochemical Corporation, Beijing 1 E china Univ Sci & Technol Lab Living Polymerizat Shanghai 200237 Peoples R China Beijing Yanshan Petrochem Corp Res Inst Beijing 102550 Peoples R China

In the present paper the synthesis of block copolymers via the transformation from living anionic polymerization (LAP) to atom transfer radical polymerization (ATRP) was described. α-Bromine-terminated polystyrenes(PStBr) in the LAP step was prepared by using n-BuLi as initiator, tetrahydrofuran (THF) as the activator, α-methylstyrene (α-MeSt) as the capping group and liquid bromine (Br_2) as the bromating agent. The effects of reaction conditions such as the amounts of α-MeSt, THF, and Br_2 as well as molecular weight of polystyrene on the bromating efficiency (BE) and coupling extent (CE) were examined. The present results show that the yield of PStBr obtained was more than 93. 8% and the coupling reaction was substantially absent. PStBr was further used as the macroinitiator in the polymerization of methyl-methacrylate (MMA) in the presence of copper (I ) halogen and 2, 2' -bipyridine (bpy) complexes. It was found that the molecular weight of the resulted PSt-b-PMMA increased linearly with the increase of the conversion of MMA and the polydispersity was 1. 2-1.6. The structures of PStBr and P(St-b-MMA) were characterized by ~1H NMR spectra.

关键词： Atom transfer radical polymerization, living anionic polymerization, Block copolymer, Macroinitiator, Bromation, α-Methylstyrene Capping reaction

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Revealing Tissue Heterogeneity and Spatial Dark Genes from Spatially Resolved Transcriptomics by Multiview Graph Networks

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Research 2024年第2期6卷 629-645页

作者： ying Li Yuejing Lu Chen kang Peiluan Li Luonan Chen School of Mathematics and Statistics Henan University of Science and TechnologyLuoyang471023China Longmen laboratory LuoyangHenan471003China Key laboratory of Systems Biology Institute of Biochemistry and Cell BiologyCenter for Excellence in Molecular Cell ScienceChinese Academy of SciencesShanghai201100China Key laboratory of Systems Health science of Zhejang Province Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou310000China School of Life science and technology ShanghaiTech UniversityShanghai201100.China

Spatially resolved transcriptomics(SRT)is capable of comprehensively characterizing gene expression patterns and providing an unbiased image of spatial *** fully understand the organizational complexity and tumor immune escape mechanism,we propose stMGATF,a multiview graph attention fusion model that integrates gene expression,histological images,spatial location,and gene *** better extract information,stMGATF exploits SimCLRv2 for visual feature exaction and employs edge feature enhanced graph attention networks for the learning potential embedding of each view.A global attention mechanism is used to adaptively integrate 3 views to obtain low-dimensional *** to diverse SRT datasets,stMGATF is robust and outperforms other methods in detecting spatial domains and denoising data even with different resolutions and *** particular,stMGATF contributes to the elucidation of tissue heterogeneity and extraction of 3-dimensional expression ***,considering the associations between genes in tumors,stMGATF can identify the spatial dark genes ignored by traditional methods,which can be used to predict tumor-driving transcription factors and reveal tumor immune escape mechanisms,providing theoretical evidence for the development of new immunotherapeutic strategies.

关键词： Spatial integrate driving

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Removal of Trace Olefins from Aromatics Catalyzed by[bmim]Br-AlCl_3 Ionic Liquid

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china Petroleum Processing & Petrochemical technology 2010年第2期12卷 41-44页

作者： Jiang Zhenghong Hou Minghui Weng Huixin Shi Li (State Key lab of Chemical Engineering,east china university of science & technology.shanghai 200237) E china Univ Sci & Technol State Key Lab Chem Engn Shanghai 200237 Peoples R China

1-Butyl-3-methylimidazolium bromochloroaluminate （[bmim]Br-AlCl3） ionic liquid was used as an acid catalyst for removal of trace olefins from the aromatic hydrocarbons. The influence of various reaction parameters such as reaction time, temperature, dosage and acid strength of catalyst was investigated. The experimental results demonstrated that the ionic liquid exhibited excellent activity under mild reaction conditions, with the conversion of olefins reaching 98.84% and the bromine index of the aromatics varying from 1129 to 13. On the basis of the results obtained, thereof, a possible reaction mechanism was proposed.

关键词： ionic liquid bromine index olefins removal aromatics catalyst

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Experimental Study of Energy-Saving Air-Conditioner with Hot Water

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湖南大学学报（自然科学版） 2009年第S1期36卷 75-78页

作者： CHEN Jian-bo,CHEN Dan,LU ying(university of shanghai for science and technology.shanghai,china) university of shanghai for science and technology Shanghai 200000 China

Energy-saving air-conditioner with hot water is an air source heat pump air-conditioner,which can also supply hot *** hot water is heated by a double pipe condenser connected with an air-cooled condenser in series in the *** experiment of the energy-saving air-conditioner was carried out in the enthalpy-difference air-conditioner *** hot water temperature and the compressor's discharge and suction pressure were recorded in the working condition,where the ambient temperature was at 43 ℃,35 ℃,21 ℃,7 ℃,and 2 ℃ *** results showed that the system operated stably and *** system can supply 240 L hot water at 50 ℃ in the whole year,and its coefficience of performance(COP)is much higher than the conventional air source heat pump *** energy conservation was proved by comparing the thermal efficiency with other sourece water heaters.

关键词： air-conditioning water heaters energy conservation heat pump systems thermal efficiency

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Removal of Trace Olefins from Aromatics by Catalytic Alkylation Using 1-Alkyl-3-methylimidazolium Bromochloroaluminate Catalyst

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china Petroleum Processing & Petrochemical technology 2011年第2期13卷 14-18页

作者： Sun Yu Shi Li(State Key laboratory of Chemical Engineering,east china university of science and technology.shanghai 200237) E china Univ Sci & Technol State Key Lab Chem Engn Shanghai 200237 Peoples R China

Removal of trace olefins from aromatic liquids had been investigated in the presence of various ionic liquids like 1-ethyl-3-methylimidazoliurn bromochloroaluminate （EMIMBr-AlCl3）, 1-butyl-3-methylimidazolium bromochloroaluminate （BMIMBr-AlCl3）, l-hexyl-3-methylimidazolium bromochloroaluminate （HMIMBr-AlCl3）, and 1-octyl-3-methylimidazolium bromochloroaluminate （OMIMBr-A1C13）. It was found that the longer the alkyl chain of ionic liquid cations was, the higher the olefins conversion would be. OMIMBr-AlCl3 （with 0.67 molar fraction of AlCl3） had an obvious performance on olefins removal. The influences of various reaction parameters such as the dosage of catalyst, the reaction temperature, and the reaction time on the reaction catalyzed by OMIMBr-AlCl3 were investigated. Under optimum reaction conditions, a higher than 99% conversion of olefins was achieved. The preliminary results revealed that the process could save time, consume less energy, separate products easier, and cause less pollution to the environment.

关键词： ionic liquids olefins removal 1-alkyl-3-methylimidazolium bromochloroaluminate aromatic

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INFLUENCE OF MIXING DEVICE ON SERUM-FREE CULTIVATION OF INSECT CELLS IN SPINNER FLASKS

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化工学报 2000年第S1期51卷 101-104页

作者： Zhao Jiao, Dai Hu and Tan Wensong (State Key lab of Bioreactor Engineering, east china university of science and technology.shanghai 200237,china)

A culture system was developed and successfully employed for the serum-free cultivation of Tn-5B1-4 (Tn5 ) insect cells. With our adaptation procedure, it was possible to obtain cells fully adapted to serum-free media in stationary T-flasks and then enable these adapted cells to grow well in spinner flasks immediately. The spinner "ask with special stirring design proved tO provide favorable culture environment that made it desirable for use in the serum-free cultivation of Tn5 cells even at low seeding density.

关键词： serum-free insect cells adaptation spinner flasks culture environment

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A Weakly-Supervised Crowd Density Estimation Method Based on Two-Stage Linear Feature Calibration

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 965-981页

作者： Yong-Chao Li Rui-sheng Jia ying-Xiang Hu Hong-Mei Sun the College of Computer science and Engineering Shandong University of Science and TechnologyQingdao 266590 the Faculty of Information science and Engineering Ocean University of ChinaQingdao 266000China the College of Computer science and Engineering Shandong University of Science and TechnologyQingdao 266590China the College of Computer science and Engineering Nanjing University of Science and TechnologyNanjing 210000China

In a crowd density estimation dataset,the annotation of crowd locations is an extremely laborious task,and they are not taken into the evaluation *** this paper,we aim to reduce the annotation cost of crowd datasets,and propose a crowd density estimation method based on weakly-supervised learning,in the absence of crowd position supervision information,which directly reduces the number of crowds by using the number of pedestrians in the image as the supervised *** this purpose,we design a new training method,which exploits the correlation between global and local image features by incremental learning to train the ***,we design a parent-child network(PC-Net)focusing on the global and local image respectively,and propose a linear feature calibration structure to train the PC-Net simultaneously,and the child network learns feature transfer factors and feature bias weights,and uses the transfer factors and bias weights to linearly feature calibrate the features extracted from the Parent network,to improve the convergence of the network by using local features hidden in the crowd *** addition,we use the pyramid vision transformer as the backbone of the PC-Net to extract crowd features at different levels,and design a global-local feature loss function(L2).We combine it with a crowd counting loss(LC)to enhance the sensitivity of the network to crowd features during the training process,which effectively improves the accuracy of crowd density *** experimental results show that the PC-Net significantly reduces the gap between fullysupervised and weakly-supervised crowd density estimation,and outperforms the comparison methods on five datasets of shanghai Tech Part A,shanghaiTech Part B,UCF_CC_50,UCF_QNRF and JHU-CROWD++.

关键词： Crowd density estimation linear feature calibration vision transformer weakly-supervision learning

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Ni-loaded Catalyst Containing Activated Clay for Maleic Anhydride Hydrogenation to Succinic Anhydride

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china Petroleum Processing & Petrochemical technology 2011年第4期13卷 35-40页

作者： Tian Weiping Guo Shaofei Shi Li (The State Key laboratory of Chemical Engineering, east china university of science and technology, shanghai 200237) E china Univ Sci & Technol State Key Lab Chem Engn Shanghai 200237 Peoples R China

In this work, the hydrogenation of maleic anhydride to succinic anhydride in the presence of 5 m%Ni/clay catalysts was investigated. These catalysts were characterized by X-ray diffraction （XRD）, H2 temperature programmed reduction （TPR） and thermogravimetric analysis （TGA） techniques. The XRD and TPR studies showed that Ni was present as Ni2＋ on the support, which indicated that there were no elemental nickel （Ni^0） and Ni203 species in the unreduced samples. Increasing of calcination temperature to 650 ℃ leads to destruction of the support structure observed in TGA, while the catalyst sample calcined at 550 ℃ exhibits better performances than other samples. The ideal conversion of maleic anhydride （97.14%） and selectivity of succinic anhydride （99.55%） were realized at a reaction temperature of 180 ℃ and a weight hourly space velocity of 4 h^-1 under a reaction pressure of 1 MPa.

关键词： maleic anhydride hydrogenation succinic anhydride nickel

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