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c.inese Journal of Polymer Science 2013年第4期31卷 550-562页

作者： Hua-hua Huang chuan-hui Zhang Ya-wei Qin hui Niu 董金勇 cAS Key Laboratory of Engineering Plastics Institute of ChemistryChinese Academy of Sciences University of c.inese Academy of Sciences

in this paper, we review our recent progress in the synthesis and application of styryl-capped polypropylene （PP-t- St）, an excellent reac.ive polyolefin that is both convenient and efficient in synthesis and facile and versatile in application for preparing advanced polypropylene materials via macromolecular engineering. The synthesis of PP-t-St is made possible by a unique chain transfer reac.ion coordinated by a bis-styrenic molecule, such as 1,4-divinylbenzene （DVB） and 1,2-bis（4- vinylphenyl）ethane （BVPE）, and hydrogen in typical c2-symmetric metallocene （e.g. rac-Me2Si（2-Me-4-Ph-ind）2Zrc12, in association with methylaluminocene, MAO） catalyzed propylene polymerization. The regio-selec.ive 2,1- insertion of the styrenic double bond in DVB or BVPE into the overwhelmingly 1,2-fashioned Zr-PP propagating chain enables substantial dormancy of the catalyst ac.ive site, which triggers selec.ive hydrogen chain transfer that, with the formed Zr-H species ultimately saturated by the insertion of propylene monomer, results in an exclusive capping of the afforded PP chains by styryl group at the termination end. With a highly reac.ive styryl group at chain end, PP-t-St has been used as a facile building block in PP macromolecular engineering together with the employment of state-of-the-art synthetic polymer chemistry to fabricate broad types of new polypropylene arc.itectures.

关键词： Polypropylene coordination polymerization Styryl terminal group Macromolecular engineering.

NK cells in liver homeostasis and viral hepatitis

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Science c.ina(Life Sciences) 2018年第12期61卷 1477-1485页

作者： hui Peng Zhigang Tian Division of Molecular Medicine Hefei National Laboratory for Physical Sciences at Microscale the CAS Key Laboratory of Innate Immunity and Chronic Disease School of Life Sciences University of Science and Technology of China institute of immunology University of Science and Technology of China

As an important member of the innate immune system, natural killer(NK) cells are well known for their rapid and efficient immune responses against infec.ious agents and tumors. NK cells are widely distributed throughout the body and are particularly enriched within the liver, where they display unique phenotypic and func.ional properties, playing important roles in various liver diseases. Herein, we present an overview of liver NK cell properties with regard to phenotype, func.ion, and subset composition at steady state, and we also summarize the complex reciprocal interac.ions between liver NK cells and other cell types within the local environment of the liver. We also provide an overview of recent advances demonstrating the roles of NK cells in viral hepatitis, including a discussion of NK cell altered states and their beneficial versus harmful effects during hepatitis B virus and hepatitis c virus infec.ion.

关键词： NK cells liver HBV HcV

Dilation theory and analytic model theory for doubly commuting sequences of c._(0)-contrac.ions

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Science c.ina Mathematics 2023年第2期66卷 303-340页

作者： hui Dan Kunyu Guo college of Mathematics Sichuan UniversityChengdu 610065China School of Mathematical Sciences Fudan UniversityShanghai 200433China

it is known that every c·_(0)-contrac.ion has a dilation to a Hardy *** leads to an elegant analytic func.ional model for c·_(0)-contrac.ions,and has motivated lots of further works on the model theory and generalizations to commuting tuples of c·_(0)-*** this paper,we focus on doubly commuting sequences of c·_(0)-contrac.ions,and establish the dilation theory and the analytic model theory for these sequences of *** results are applied to generalize the Beurling-Lax theorem and Jordan blocks in the multivariable operator theory to the operator theory in the infinite-variable setting.

关键词： doubly commuting sequence dilation theory analytic func.ional model Beurling-Lax theorem Jordan block

An experimental determination of W,Nb,and Ta partition coefficients between P-rich peraluminous granitic melt and coexisting aqueous fluid

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c.inese Journal Of Geochemistry 2015年第2期34卷 194-200页

作者： Yong Tang hui Zhang Laboratory for High Temperature and High Pressure Study of the Earth's interior Institute of GeochemistryChinese Academy of Sciences

The partition coefficients of W,Nb,and Ta between the P-rich peraluminous granitic melt and the coexisting aqueous fluid were determined at 800-850 °c and 0.5-1.5 *** experimental results showed that the partition coefficients D_w,D_(Nb) and D_(Ta)(D_i^(v/m) = c.i^V/c.i^m,where c.i^V and c.i^m denote the concentrations of an element,i,in the aqueous fluid and the melt,respec.ively) were less than *** partition coefficients were affected by pressure,but there was no evidence for the complexation of P2O5 with these elements in the granitic melt or aqueous fluid,except for with W in the *** results showed that W,Nb,and Ta tended to partition into the granitic melt and,in the late period of crystallization of P-rich magma,they formed independent minerals.

关键词：分配系数实验测定水流体过铝质熔体 Nb 共存钽

comparative Analyses of Vertical Structure of Deep convec.ive clouds Retrieved from Satellites and Ground-Based Radars at Naqu over the Tibetan Plateau

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Journal of Meteorological Research 2019年第3期33卷 446-462页

作者： hui Wang Xueliang Guo State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences China Meteorological Administration Beijing 100081 Key Laboratory for cloud Physics of c.ina Meteorological Administration Chinese Academy of Meteorological Sciences China Meteorological Administration Beijing 100081

in order to improve understanding of deep convec.ive clouds over the Tibetan Plateau, characteristics of vertical structure of a deep strong convec.ive cloud over Naqu station and a deep weak convec.ive cloud approximately 100 km to the west of Naqu station, which occurred over 1300-1600 Beijing Time (BT) 9 July 2014 during the Third Tibetan Plateau Atmospheric Science Experiment (TiPEX-Ⅲ), are analyzed, based on multi-source satellite data from TRMM, cloudSat, and Aqua, and radar data from ground-based vertically pointing radars (c-band frequency-modulated continuous-wave radar and KA-band millimeter wave cloud radar). The results are as follows.(1) The horizontal scales of both the deep strong and deep weak convec.ive clouds were small (10-20 km), and their tops were high[15-16 km above sea level (ASL)]. Across the level of 0℃ isotherm in the deep strong convec.ive cloud, the reflec.ivity increased rapidly, suggesting that the melting process of solid precipitation particles through the 0℃ level played an important role. A bright band located at 5.5 km ASL (i.e., 1 km above ground level) appeared during the period of convec.ion weakening.(2) The reflec.ivity values from TRMM precipitation radar below 11 km were found to be overestimated compared to those derived from the c-band frequency-modulated continuous-wave radar.(3) Deep convec.ive clouds were mainly ice clouds, and there were rich small ice particles above 10 km, while few large ice particles were found below 10 km. The microphysical processes of deep strong and deep weak convec.ive clouds mainly included mixed-phase process and glaciated process, and the mixed-phase process can be divided into two types:one was the rimming process below the level of -25℃(deep strong convec.ive cloud) or -29℃(deep weak convec.ive cloud) and the other was aggregation and deposition process above that level. The latter process was accompanied with fast increase in ice particle effec.ive radius. The above evidence from space-

关键词： deep convec.ive clouds the Tibetan Plateau vertical structure satellite retrieval radar observation

Mechanical properties and wear resistance of ultrafine bainitic steel under low austempering temperature

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international Journal of Minerals,Metallurgy and Materials 2020年第4期27卷 483-493页

作者： Wei Liu You-hui Jiang hui Guo Yue Zhang Ai-min Zhao Yao Huang collaborative innovation center of Steel Technology University of Science and Technology BeijingBeijing 100083China School of Mechanical Engineering Weifang University of Science and TechnologyShouguang 262700China c.ina Electric Power Research institute Beijing 100192China

The mechanical properties and wear resistance of the ultrafine bainitic steel austempered at various temperatures were *** electron microscopy(SEM)and X-ray diffrac.ion were used to analyze the *** worn surfaces were observed via laser scanning confocal microscopy and *** indicated that,under low austempering temperatures,the mechanical properties differed,and the wear resistance remained basically *** tensile strength of the samples was above 1800 MPa,but only one sample austempered at 230°c had an elongation of more than 10%.The weight loss of samples was approximately linear with the cycles of wear and nonlinear with the *** samples showed little difference in wear resistance at different isothermal temperatures,whereas the thickness of their deformed layers varied *** results are related to the initial hardness of the sample and the stability of the retained ***,the experimental results showed that the effect of austempering temperature on the wear resistance of ultrafine bainitic steel can be neglected under low applied loads and low austempering temperature.

关键词： bainitic steel mechanical properties wear resistance austempering temperature

EFFEcT OF DAMAGE EVOLUTiON ON POiSSON'S RATiO OF cONcRETE UNDER SULFATE ATTAcK

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Acta Mechanica Solida Sinica 2011年第3期24卷 209-215页

作者： hui Song Jiankang chen The Faculty of Mechanical Engineering and Mechanics Ningbo University Ningbo 315211 China State Key Laboratory of Turbulence and complex Systems Peking University Beijing 100871 China

Experimental results about concrete under sulfate attack are summarized, which include the variation of mass density of samples and velocity of ultrasonic wave propagating in samples. The evolution damage is analyzed in terms of the experimental results, and close attention is paid to the effect of damage evolution on Poisson＇s ratio. This study shows that Poisson＇s ratio is significantly affected by the concentration of solution and water-cement ratio. Poisson＇s ratio of concrete changes very little when the water-cement ratio is selected as 0.6 or 0.8, so that such change may be neglected. if water-cement is 0.4, however, the Poisson＇s ratio of the sample significantly changes. When the concrete sample of 0.4 water-cement ratio is immersed in sodium sulfate solution of 8% concentration for 285 days, Poisson＇s ratio increase 10.14% compared with its initial value. There exist a sensitive region and a non-sensitive region for the change rate of Poisson＇s ratio with respect to corrosion time. The change rate of Poisson＇s ratio monotonously decreases with corrosion time in the sensitive region; in the non-sensitive region, the change rate of Poisson＇s ratio is almost equal to zero.

关键词： concrete sulfate attack porosity Poisson's ratio damage evolution

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c_(8)芳烃异构化径向床反应器数值模拟

石油炼制与化工 2025年第1期56卷 76-85页

作者：党辉鲍迪唐晓津侯栓弟康承琳中石化石油化工科学研究院有限公司北京100083 中石化(大连)石油化工研究院有限公司

为研究c_(8)芳烃异构化径向床反应器内部流场分布和反应性能,建立了c_(8)芳烃异构化径向床反应器模拟计算模型。通过引入多孔介质和反应动力学方程模型,对反应器内部流场和反应过程进行了模拟计算。结果表明,催化剂床层内,压力沿轴向由... 详细信息

为研究c_(8)芳烃异构化径向床反应器内部流场分布和反应性能,建立了c_(8)芳烃异构化径向床反应器模拟计算模型。通过引入多孔介质和反应动力学方程模型,对反应器内部流场和反应过程进行了模拟计算。结果表明,催化剂床层内,压力沿轴向由高到低呈下降趋势,速度呈现两端高、中间低的分布规律。沿径向方向,流体的流动压降较低。反应产物(对二甲苯)质量分数由扇形筒出口至中心管入口逐渐增大,且在不同轴向高度床层上变化规律相同。模拟计算得到的出口各组分质量分数与实际出口数据基本吻合,说明所建立的反应器模型能够较好地描述c_(8)芳烃异构化径向床反应器的反应性能。

关键词： c_(8)芳烃异构化径向床反应器计算流体力学(cFD) 反应动力学

A priori estimates versus arbitrarily large solutions for frac.ional semi-linear elliptic equations with c.itical Sobolev exponent

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Science c.ina Mathematics 2023年第9期66卷 1965-1992页

作者： Xusheng Du hui Yang Department of Mathematics The Hong Kong University of Science and TechnologyHong KongChina

We study positive solutions to the frac.ional semi-linear elliptic equation(−∆)σu=K(x)u n+2σn−2σin B2\c.iwith an isolated singularity at the origin,where K is a positive func.ion on B2,the punctured ball B2\c.i⊂Rn with n>2,σ∈(0,1),and(−∆)σis the frac.ional *** lower dimensions,we show that for any K∈c1(B2),a positive solution u always satisfies that u(x)6 c|x|−(n−2σ)/2 near the *** contrast,we construct positive func.ions K∈c1(B2)in higher dimensions such that a positive solution u could be arbitrarily large near the *** particular,these results also apply to the presc.ibed boundary mean curvature equations on B n+1.

关键词： frac.ional elliptic equations boundary mean curvature equations local estimates large singular solutions

comparative study on electrochemical degradation of 4-chlorophenol by different Pd/c gas diffusion electrodes

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Science c.ina chemistry 2007年第5期50卷 692-699页

作者： WANG hui WANG JianLong Laboratory of Environmental Technology INET Tsinghua University Beijing 100084 China Laboratory of Environmental Technology INET Tsinghua University Beijing 100084 China

Pd/c catalyst used for the Pd/c gas diffusion cathodes was prepared by hydrogen reduc.ion method and formaldehyde reduc.ion method, and characterized by X-ray diffrac.ion (XRD), transmission elec- trode microcopy (TEM), X-ray photoelectron spectroscopy (XPS), and cyc.ic voltammetry (cV) tech- niques. The electrochemical degradation of 4-chlorophenol was investigated in the diaphragm elec- trolysis system, aerating firstly with hydrogen gas then with air, using three different kinds of gas dif- fusion cathode. The results indicated that the self-made Pd/c gas diffusion cathode can not only re- duc.ively dechlorinate 4-chlorophenols by aerating hydrogen gas, but also accelerate the two-electron reduc.ion of O2 to hydrogen peroxide (H2O2) by aerating air. Therefore, the removal efficiency of 4-chlorophenol by using Pd/c gas diffusion cathode is better than that of the c/PTFE gas diffusion cathode (no catalyst). The catalytic ac.ivity of Pd/c catalyst prepared by hydrogen reduc.ion method is higher than that prepared by formaldehyde reduc.ion method. The stability of the Pd/c gas diffusion cathodes is good. Therefore, both the removal efficiency and the dechlorination degree of 4-chlorophenol reached about 100% after 60 min, and the removal efficiency of 4-chlorophenol in terms of chemical oxygen demand (cOD) in the cathodic compartment reached 87.4% after 120 min.

关键词： electrochemical oxidation, gas diffusion cathode, Pd/c catalyst, chlorophenol