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SYNTHESIS OF pH-RESPONSIVE AMPHIPHILIC DIBLOCK COPOLYMERS CONTAINING POLYISOBUTYLENE via OXYANION-INITIATED POLYMERIZATION AND THEIR MULTIPLE SELF-ASSEMBLY MORPHOLOGIES

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Chinese Journal of Polymer Science 2013年第2期31卷 218-231页

作者： Huai-chao Wang Ming-zu Zhang 倪沛红 Jin-lin He Ying Hao Yi-xian Wu College of Chemistry Chemical Engineering and Materials Science Soochow University Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application Soochow University State Key Lab of Chemical Resource Engineering Beijing University of Chemical Technology

Two pH-responsive amphiphilic diblock copolymers, namely polyisobutylene-block-poly[2-（N,N- dimethylamino）ethyl methaerylate] （PIB-b-PDMAEMA） and polyisobutylene-block-poly（metharylic acid）（PIB-b-PMAA）, were synthesized via oxyanion-initiated polymerization, and their multiple self-assembly behaviors have been studied. An exo-01efin-terminated highly reactive polyisobutylene （HRPIB） was first changed to hydroxyl-terminated PIB （PIB-OH） via hydroboration-oxidation of C =C double bond in the chain end, and then reacted with KH to yield a potassium alcoholate of PIB （PIB-O-K＋）. PIB-O-K＋ was immediately used as a macroinitiator to polymerize DMAEMA monomer, resulting in a cationic diblock copolymer PIB-b-PDMAEMA. With the similar synthesis procedure, the anionic diblock copolymer PIB-b- PMAA could be prepared via a combination of oxyanion-initiated polymerization of tert-butyl methacrylate （tBMA） and subsequent hydrolysis of tert-butyl ester groups in PtBMA block. The functional PIB and block copolymers have been fully characterized by 1H-NMR, FT-IR spectroscopy, and gel permeation chromatography （GPC）. These samples allowed us to systematically investigate the effects of block composition on the pH responsivity and various self-assembled morphologies of the copolymers in THF/water mixed solvent. Transmission electron microscopy （TEM） images revealed that these diblock copolymers containing small amount of original PIB without exo-olefin-terminated group are able to self-assemble into micelles, vesicles with different particle sizes and cylindrical aggregates, depending on various factors including block copolymer composition, solvent polarity and pH value.

关键词： Oxyanion-initiated polymerization Polyisobutylene Stimuli responsivity Amphiphilic copolymer Self- assembly.

Analysis of Time-domain Electromagnetic Scattering Problem by Multiple Cavities

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Acta Mathematicae Applicatae Sinica 2020年第1期36卷 18-48页

作者： Yang LIU Yi-xian GAO Jian zu School of Mathematics and Statistics and Center for Mathematics and Interdisciplinary SciencesNortheast Normal UniversityChangchunJilin 130024China

The time-domain multiple cavity scattering problem,which arises in diverse scientific areas,has significant industrial and military *** multiple cavities,embedded in an infinite ground plane,is filled with inhomogeneous media characterized by variable dielectric permittivities and magnetic *** to the transverse electric,the scattering problem can be studied by the Helmholtz equation in frequency domain and wave equation in time-domain respectively.A novel transparent boundary condition in time-domain is developed to reformulate the cavity scattering problem into an initial-boundary value problem in a bounded *** well-posedness and stability of the reduced problem are ***,a priori energy estimates for the electric field is obtained with minimum regularity requirement for the data and an explicit dependence on the time by studying the wave equation directly.

关键词： Helmholtz equation wave equation multiple cavities stability a priori estimates

Two New Diterpenoids from Isodon rubescens

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Chinese Chemical Letters 2000年第1期11卷 43-44页

作者： Bao lin LI Shao Nong CHEN Zhi xian SHI Xuan TIAN Yao zu CHEN National Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000 Shanghai Institute of Materia Medica Academia SinicaShanghai 200031 Northwest Plateau Institute of Biology Academia SinicaXining 810001

Two new diterpenoids taibairubescensin A (1) and B (2) have been isolated from Isodon rubescens. The structures of compound 1 and 2 were elucidated as 2 beta,3 beta-diacetoxy-11 beta,13 alpha-dihydroxy-ent-kaur- 16-en-15-one (1) and 3 beta,11 beta-diacetoxy-2 beta,6 alpha-dihydroxy-ent-kaur-16-en-15-one (2) on the basis of spectroscopic analysis.

关键词： Isodon rubescens taibairubescensin A taibairubescensin B ent-kaurene diterpenoids

NUMERICAL SIMULATION FOR SHALLOW FLOW AND POLLUTANT DISPERSION BASED ON QUAD-TREE MESHES

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Journal of Hydrodynamics 2006年第2期18卷 161-169页

作者： LIU Xiao-dong HUA zu-lin State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow LakesCollege of Environmental Science and Engineering Hohai UniversityNanjing 210098 China

A 2D depth-averaged flow-pollutant coupled model based on quad-tree meshes was established to accurately simulate flows in water areas with irregular natural boundaries in this paper. The grids were generated by recursive subdivision about seeding points. A new neighbor-finding algorithm was presented. The governing equations were discrctized in collocated conservative variables by using the finite volume method, and the normal flux of mass, momentum and pollutants across the interlace between cells were computed by a Godunov-type Flux Difference Splitting （FDS） scheme. The model was applied to simulate flow fields around a groin. The computed values are in agreement with observed data. The results indicate that quad-tree meshes have fine local resolution, high efficiency and easy local refinement. It is clear that the quad-tree grid model can offer gains in efficiency when applied to complex flow domains or strong shear flows. Finally the model is applied to flow fields and concentration fields simulation in Jiangsu Haizhou Bay. The simulated polluted area is matched well with observations. Therefore, this model can be used to predict flow and concentration fields of actual water area with irregular natural land boundaries.

关键词： quad-tree grid shallow flow numerical simulation dispersion Godunov-type

Leakage Current Estimation of CMOS Circuit with Stack Effect

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Journal of Computer Science & Technology 2004年第5期19卷 708-717页

作者： Yong-JunXu zu-YingLuo Xiao-WeiLi Li-JianLi xian-LongHong InstituteofComputingTechnology TheChineseAcademyofSciencesBeijing100080P.R.China DepartmentofComputerScienceandTechnology TsinghuaUniversityBeijing100084P.R.China GraduateSchoolofChineseAcademyofSciences Beijing100039P.R.China NationalASICDesignEngineeringCenter InstituteofAutomationTheChineseAcademyofSciencesBeijin100080P.R.China

Leakage current of CMOS circuit increases dramatically with the technologyscaling down and has become a critical issue of high performance system. Subthreshold, gate andreverse biased junction band-to-band tunneling (BTBT) leakages are considered three maindeterminants of total leakage current. Up to now, how to accurately estimate leakage current oflarge-scale circuits within endurable time remains unsolved, even though accurate leakage modelshave been widely discussed. In this paper, the authors first dip into the stack effect of CMOStechnology and propose a new simple gate-level leakage current model. Then, a table-lookup basedtotal leakage current simulator is built up according to the model. To validate the simulator,accurate leakage current is simulated at circuit level using popular simulator HSPICE forcomparison. Some further studies such as maximum leakage current estimation, minimum leakage currentgeneration and a high-level average leakage current macromodel are introduced in *** on ISCAS85 and ISCAS89 benchmarks demonstrate that the two proposed leakage currentestimation methods are very accurate and efficient.

关键词： computer-aided design leakage current estimation stack effect macromodeling propagation of signal probability

Modeling and Analysis of Mesh Tree Hybrid Power／Ground Networks with Multiple Voltage Supply in Time Domain

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Journal of Computer Science & Technology 2005年第2期20卷 224-230页

作者： Yi-CiCai JinShi zu-YingLuo xian-LongHong DepartmentofComputerScienceandTechnology TsinghuaUniversityBeijing100084P.R.China

This paper proposes a novel algorithm, which can be used to model and analyzemesh tree hybrid power/ground distribution networks with multiple voltage supply in time *** only this algorithm enhances common method''s ability on analysis of power/ground network withirregular topology, but also very high accuracy it keeps. The accuracy and stability of thisalgorithm is proved using strict math method in this paper. Also, the usage of both preconditiontechnique based on Incomplete Choleskey Decomposition and fast variable elimination technique hasimproved the algorithm''s efficiency a lot. Experimental results show that it can finish the analysisof power/ground network with enormous, size within very short time. Also, this algorithm can beapplied to analyze the clock network, bus network, and signal network without buffer under highworking frequency because of the independence of the topology.

关键词： VLSI power/ground network simulation mesh tree hybrid multi-source choleskey decomposition fast variable elimination

Security Region: An Intelligent Approach to Transportation Networks

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CSEE Journal of Power and Energy Systems 2023年第4期9卷 1532-1539页

作者： Jun Xiao Menghao Long Guoqiang zu Qisi lin Key Laboratory of Smart Grid of Ministry of Education Tianjin UniversityTianjin 300072China State Grid Tianjin Chengdong Electric Power Supply Company Tianjin 300250Chin State Grid Tianjin Electric Power Research Institute Tianjin 300384China.

This paper proposes a security region of transporta-tion networks,which is defined as the set of flow states(operating points)satisfying the N-1 security in transportation *** boundary of the set is closed,inside all the operating points are N-1 secure;oppositely,outside all the operating points are ***,N-1 security of the transportation networks is defined,which means that when a road is blocked,vehicles on other roads within the networks can also reach their destination through different paths without being trapped on the ***,the security region of transportation networks is *** algorithm of a boundary calculation is studied and the boundary equations of security distances are ***,the proposed security of the transportation networks is presented in different *** paper demonstrates the following:1)the security region can be accurately predicted by the simulation of N-1;2)the boundary distance can show the necessary degree of security;3)security can be improved by a preventive control *** simulation on TransCAD is used to verify the correctness of the *** Terms-Boundary distance,evolution,security region,transportation network,TransCAD.

关键词： Boundary distance evolution security region transportation network TransCAD.

Exosomes Derived from Hydroquinone-transformed Human Bronchial Epithelial Cells Inhibited Recipient Cell Apoptosis by transferring miR-221

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Biomedical and Environmental Sciences 2021年第7期34卷 520-527页

作者： xian Hong Yi CHEN Ying ZHANG Jia Ying TANG Mei lin LIAN Zhen Wei JIANG Ran HU zu Qing LI Yan Feng HU Da lin Department of Environmental Health Guangdong Provincial Key Laboratory of Tropical Disease ResearchSchool of Public HealthSouthern Medical UniversityGuangzhou 510515GuangdongChina Grade 2017 Undergraduate Student Majoring in Preventive Medicine School of Public HealthSouthern Medical UniversityGuangzhou 510515GuangdongChina Grade 2018 Undergraduate Student Majoring in Clinical Medicine Department of Clinical MedicineJiamusi UniversityJiamusi 154007HeilongjiangChina

Objective Although benzene is a confirmed environmental carcinogen,the mechanism of its carcinogenicity remains largely *** suggested oncogene,miR-221,is elevated and plays important roles in various tumors,but its role in benzene-induced carcinogenesis remains *** In the present study,we constructed hydroquinone(HQ,a representative metabolite of benzene with biological activity)-transformed malignant cell line(16 HBE-t)and analyzed the level of miR-221 in it with *** from 16 HBE-t cells incubated with or without an miR-221 inhibitor were isolated by ultracentrifugation,characterized by transmission electron microscopy and laser scanning confocal microscope,and then transfected into 16 HBE *** effects of exosomal miR-221 on apoptosis induced by HQ in recipient cells were determined using flow *** The amount of miR-221 in 16 HBE-t was significantly increased compared with *** recipient cells ingested exosomes derived from 16 HBE-t,miR-221 was increased,and apoptosis induced by HQ was *** miR-221 in 16 HBE-t using an inhibitor did not significantly alter miR-221 or apoptosis in recipient *** Exosomal miR-221 secreted by 16 HBE-t inhibits apoptosis induced by HQ in normal recipient cells.

关键词： Benzene Toxic mechanism Apoptosis Exosomes miR-221 Intercellular communications

Decadal variation of thermocline-sea surface temperature feedback in the tropical Indian Ocean and the underlying mechanisms

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Acta Oceanologica Sinica 2021年第11期40卷 31-38页

作者： Meiqi Zhang Shuangwen Sun lin Liu Yongcan zu lin Feng First Institute of Oceanography and Key Laboratory of Marine Science and Numerical ModelingMinistry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Shandong Key Laboratory of Marine Science and Numerical Modeling Qingdao 266061China

The thermocline-sea surface temperature(SST)feedback is the most important component of the Bjerknes feedback,which plays an important role in the development of the air-sea coupling modes of the Indian *** thermocline-SST feedback in the Indian Ocean has experienced significant decadal variations over the last40 *** feedback intensified in the late twentieth century and then weakened during the hiatus in global warming at the early twenty-first *** thermocline-SST feedback is most prominent in the southeastern and southwestern Indian *** the decadal variations of feedback are similar in these two regions,there are still differences in the underlying *** decadal variations of feedback in the southeastern Indian Ocean are dominated by variations in the depth of the thermocline,which are modulated by equatorial zonal wind *** the decadal variation of feedback in the southwestern Indian Ocean is mainly controlled by the intensity of upwelling and thermocline depth in winter and spring,*** upwelling and thermocline depth are both affected by wind stress curl anomalies over the southeastern Indian Ocean,which excite anomalous Ekman pumping and influence the southwestern Indian Ocean through westward propagating Rossby waves.

关键词： Indian Ocean thermocline-SST feedback decadal variation upwelling thermocline depth