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In Situ Variation of Interpenetrating Polymer Network Topology using a Photolabile Connector

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Chinese Journal of Polymer Science 2022年第11期40卷 1317-1322页

作者： Xin-Hong Xiong lu-lu Xue sheng Wang Shi-Fang Zhao Xiang Guo Mei Li jia-Xi Cui Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou313001China Department of Bioengineering University of PennsylvaniaPhiladelphiaPennsylvania19104USA College of Chemistry and Molecular Engineering Peking UniversityBeijing100871China School of medicine Shaoxing UniversityShaoxing312000China School of Materials Science and Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan250353China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu610054China

A photo-controlled approach is developed to regulate the interpenetrating polymer network(IPN)topology by varying the connecting structure between the first and second *** approach is based on multifunctional inimer(Vinyl-o NB-Br)possessing three moieties,i.e.,an acrylate-based double bond for incorporation within a polymer network,a Br group for grafting polymerization to get connectIPN(c-IPN),and an o-nitrobenzyl spacer for photocleaving to convert the c-IPN to disconnected-IPN(d-IPN)with UV light *** design allows for finely controlling the connection degree between two networks.A systematic study on the mechanical property of a series of samples with different connection degrees thus can be *** results reveal that decreasing the connecting degree between two networks of IPN made a negligible contribution to materials'mechanical properties.

关键词： Interpenetrating polymer network Network topology o-Nitrobenzyl Inimer Mechanical property

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有机聚合物锂电池正极材料的制备与研究

江西化工 2019年第6期35卷 334-337页

作者：赵经纬陈嘉苗陆嘉晟王晓芳籍少敏霍延平九江天赐高新材料股份有限公司江西九江332000 广东工业大学轻工化工学院广东广州510006 中国科学院上海有机化学研究所有机氟化学中国科学院重点实验室上海200032

随着储能电源和以及电动汽车的迅速发展,开发高能量密度的锂离子电池成为现阶段研究的重点方向之一。目前,广泛使用的无机正极材料普遍存在容量提升有限,生产过程消耗能源大,存在安全隐患和成本高等缺陷。与无机正极材料相比,有机物正... 详细信息

随着储能电源和以及电动汽车的迅速发展,开发高能量密度的锂离子电池成为现阶段研究的重点方向之一。目前,广泛使用的无机正极材料普遍存在容量提升有限,生产过程消耗能源大,存在安全隐患和成本高等缺陷。与无机正极材料相比,有机物正极材料具有理论比容量高,原料丰富,柔韧性强,环境友好,结构可设计性强和体系安全等的优点,对于有机化合物来说,共轭羰基化合物非常适合用做下一代新型的绿色锂离子电池电极材料。本文通过选择3,4,9,10-苝四甲酸二酐为基础,通过合成它的聚合物材料,达到改善电化学性能的目的,取得了一定的效果,为今后的有机正极材料的发展提供了方向。

关键词：有机化合物锂离子电池正极材料电化学性能

A study on the catalytic performance of carbide slag in transesterification and the calculation of kinetic parameters

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Science China(Technological Sciences) 2015年第2期58卷 258-265页

作者： LIU Meng Qi NIU sheng Li lu Chun Mei LI Hui HUO Meng jia School of Energy and Power Engineering Shandong University

The catalytic performance of carbide slag in transesterification is investigated and the reaction kinetic parameters are calculated. After being activated at 650℃, calcium compounds of carbonate and hydroxide in the carbide slag are mainly transformed into calcium oxide. The activated carbide slag utilized as the transesterification catalyst is characterized by X-ray diffraction （XRD）, attenuated total reflectance-Fourier transform infrared spectroscopy （ATR-FTIR）, nitrogen adsorption-desorption and the Hammett indicator method. Compared with the carbide slag activated at 700 and 800℃, the largest surface area of 22.63 m2g^-1, the smallest particle size of 265.12 nm and the highest catalytic efficiency of the carbide slag activated at 650℃ guarantee its capacity in catalyzing transesterification. Then, the influences of activated temperature （Ta）, molar ratio of methanol to oil （γ）, catalyst added amount （ζ）, reaction temperature （Tr） and reaction time （τ） on the catalytic performance are investi- gated. Under the optimal transesterification condition of Ta=650℃, γ=15, ζ=3%, Tr=60℃ and τ=-110 rain, the catalytic efficiency of 92.98% can be achieved. Finally, the kinetic parameters of transesterification catalyzed by the activated carbide slag are calculated, where activation energy （E） is 68.45 kJ mol^-1 and pre-exponential factor （k0） is 1.75×10^9 min^-1. The activated carbide slag shows better reused property than calcium hydroxide.

关键词： transesterification catalyst carbide slag kinetic parameters

Resource allocation for the cluster-based cooperative multicast in OFDM-based cognitive radio systems

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The Journal of China Universities of Posts and Telecommunications 2013年第4期20卷 1-7,33页

作者： ZHANG Shuang-lu XU Wen-jun LI sheng-yu LIN jia-ru School of Information and Communication Engineering Beijing University of Posts and Telecommunications

This paper investigates the resource allocation problem for the cluster-based cooperative multicast in orthogonal frequency division multiplexing （OFDM）-based cognitive radio （CR） systems. Aiming at maximizing the system sum rate, an efficient clustering scheme is proposed. It begins with the clustering phase where secondary users （SUs） with good channel conditions are selected as cluster heads, while others decide to which cluster they belong. When the clusters are organized, it turns to a two-stage data transmission phase： in stage 1, the secondary＇ base station （BS） transmits data to the cluster heads; in stage 2, the cluster heads forward the received data to their cluster members. Based on this scheme, a joint subcarrier and power allocation algorithm is proposed. Simulation results show that the proposed scheme significantly outperforms the conventional multicast （CM） as well as the multiple description coding multicast 0VIDCM） in terms of the system sum rate.

关键词： cooperative multicast cognitive radio OFDM cluster

Manufacturing and testing of X-ray imaging components with high precision

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光学精密工程 2005年第5期13卷 620-625页

作者： HU jia sheng WU Xü School of Electronic and Information Engineering Dalian University of Technology Dalian 116024China College of Information Technology Dalian Maritime University Dalian 116026 China

In the latest 20 years, X ray imaging technology has developed rapidly in order to meet the needs of X-ray photo-etching, spatial exploration technology, high-energy physics, procedure diagnosis of ICF,etc. Since refractive indices of materials in the X-ray region are lower than 1, and X-ray is strongly absorbed by materials, the characteristics of X-ray increase greatly difficulty to obtain X-ray image. Conventional imaging methods are hardly suitable to X-ray range. In general, grazing reflective imaging and coding aperture imaging methods have been adopted more and more. We have designed a non coaxial grazing reflective X ray microscope which is composed of four spherical mirrors, in order to satisfy the requirement of the diagnosis of inertial confinement fusion （ICF）. The four mirrors have the same radius of curvature. The radius of each mirror is 29 000 mmand the aperture is 30 mm×15 mm. Allowable tolerance of the radius is ≤0.2% and one of surface roughness （rms） is ≤0.6 nm. Evidently it is very difficult to fabricate and test such mirrors. In order to obtain eligible mirrors, we choose 18 mirror roughcasts and array them on a round disk according to format. The combined manufacturing method can ensure high accordant quality. The fabricated mirrors are tested by both templet and double round aperture methods. Radius errors of the mirrors is about 53 mm. The surface roughness （rms） of the mirrors is inspected by the relative interferometric equipment （WYKO） and atomic force microscope. Before and after coating the measured surface roughness is averagely 0.52 nm and 0.4 nm, respectively.

关键词： X光线图像质量评价纳米精度

Technological optimization of fully mechanized caving mining face with large mining heights

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Journal of Coal Science & Engineering(China) 2013年第3期19卷 290-294页

作者： lu-jia FAN sheng-Li YANG Faculty of Resources and Safety Engineering China University of Mining and Technology (Beijing) Beijing 100083 China

Fully mechanized cave mining with large mining height is a new mining method, due to its large mining thickness and lower roadway excavation, the technology has been widely used in China＇s thick seam mining. In order to improve the top-coal recovery ratio of fully mechanized cave mining with large mining height, a study was conducted on optimizing the caving process, based on the mechanized caving face 1302N in Longgu Coal Mine. This was achieved by improving the PFC numerical calculation methods, and establishing a more accurate model system. On this basis, the recovery ratio of the top coal in different drawing intervals and technologies was investigated in order to achieve a reasonable caving process. The top-coal tracking system was used for practical surveying of the recovery ratio of top coal.

关键词： fully mechanized caving face large mining height caving process optimization numerical calculation by PFC top-coal tracking system

Uniform Exponential Attractor for Nonautonomous Partly Dissipative Lattice Dynamical System

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Acta Mathematica Sinica,English Series 2014年第8期30卷 1381-1394页

作者： sheng Fan ZHOU jia jia LOU Department of Mathematics Zhejiang Normal University Zhengzhou 63 Middle School

In this paper,we consider the existence of a uniform exponential attractor for the nonautonomous partly dissipative lattice dynamical system with quasiperiodic external forces.

关键词： Nonautonomous partly dissipative lattice systems uniform exponential attractor continuous process

A Photometric Study of the W UMa-Type Contact Binary RZ Com

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Chinese Journal of Astronomy and Astrophysics 2008年第4期8卷 465-471页

作者： jia-jia He sheng-Bang Qian National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China United Laboratory of Optical Astronomy Chinese Academy of Sciences （ULOAC） Beijing 100012 China Graduate School of Chinese Academy of Sciences Beijing 100049 China

We present results of CCD photometric observations of the short-period W UMatype contact binary system, RZ Com. The light curve of the binary has changed from Wsubtype to A-subtype from 1998 to 2003, then back to W-subtype in 2004. An analysis was carried out using the 2003 version of the Wilson-Devinney code. It is confirmed that RZ Com is a low-degree, overcontact f = 20.1% （±7.4%） binary system with a high inclination of i = 81.°40 （＋0.°40）, and a mass ratio q = 2.351 （＋0.031）. Combining four newly determined times of light minimum with others in the literature, the variations in orbital period is examined. A small-amplitude oscillation （A=0.0065d）, with a period of 41.5 year, is discovered superimposed on a long-term increase at rate dP/dt = ＋3.97 × 10^-8d yr^-1. The period oscillation can be explained either by the light-time effect due to the presence of an unseen third body, or by cycles of magnetic activity on the components. Combining our photometric solution with the spectroscopic elements obtained by Mclean ＆ Hilditch, the absolute dimensions ofRZ Com are： M1 = 1.14 （±0.19）M⊙, M2 = 0.50 （±0.09）M⊙, R1 = 1.12 （±0.01）R⊙, R2 = 0.78 （＋0.01）R⊙ and A = 2.41 （±0.02）R⊙.

关键词： stars binaries close - stars binaries eclipsing - stars individual RZ Com

Chemical Recycling of Poly(ethylene furanoate)into Value-added Poly(ethylene-co-isosorbide furanoate)

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Chinese Journal of Polymer Science 2023年第10期41卷 1533-1542页

作者： Jing Li sheng Wang Huan-Jun lu Ying-jia Lan Xiao-Hong Li Ying-Feng Tu jiangsu Engineering Laboratory of Novel Functional Polymeric Materials State and Local Joint Engineering Laboratory for Novel Functional Polymeric MaterialsCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou215123China jiangsu Key Laboratory for Micro and Nano Heat Fluid Flow Technology and Energy Application School of Physical Science and TechnologySuzhou University of Science and TechnologySuzhou215009China

We present here a novel strategy for the chemical recycling of bio-based poly(ethylene furanoate)s(PEF)to value-added high-performance bio-based poly(ethylene-co-isosorbide furanoate)(PEIF)copolyesters by the combination of cyclodepolymerization method with rapid cascade polycondensation-coupling ring-opening polymerization(PROP).The solution cyclodepolymerization of commercially available PEF affords cyclic oligo(ethylene 2,5-furandicarboxylate)s(COEFs),and the effects of reaction conditions on the yield of COEFs were *** copolyesters with different isosorbide(IS)contents were synthesized via the cascade PROP of COEFs with IS,which show significant enhanced glass transition *** melt spinning,PEIF fibers with different orientation factors were prepared,with excellent thermal stability and mechanical *** obtained PEIF fibers can lift a weight∼25000 times higher than its *** PEIF fibers are stable under ambient conditions but are biodegradable following the“surface erosion”*** sustainable value-added biodegradable PEIF fibers offer a solution to the environmentally friendly fibers.

关键词： Bio-based Chemical recycling Fiber PROP Sustainable