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Shear-induced Crystallization in Phase-separated Blends of Isotactic Polypropylene with Ethylene-Propylene-Diene Terpolymer

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Chinese Journal of Polymer Science 2015年第11期33卷 1538-1549页

作者：马桂秋 Da Li jing sheng School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin University

The compatibility between isotactic polypropylene（iPP） and ethylene-propylene-diene terpolymer（EPDM） in the blends was studied. SAXS analysis indicates that iPP and EPDM phases in the binary blend are incompatible. Isothermal crystallization behaviors of iPP in phase-separated iPP/EPDM were studied by in situ POM equipped with a Linkam shear hot stage. It was found that typical spherulites of iPP were formed both in neat iPP and in iPP/EPDM blends. The radial growth rate（d R/dt） of spherulites of iPP in the blend was not influenced by EPDM phases. Further investigations on isothermal crystallization of iPP in iPP/EPDM after shear with a fixed shear time showed that the crystallization rate of iPP in the blends increased with increasing shear rates, whereas, the crystallization rate was much lower than that of neat iPP. WAXD results showed that β-crystal iPP was formed in neat iPP as well as in iPP/EPDM blends after shearing and the percentage of β-crystal bore a relationship to the applied shear rate. The presence of EPDM resulted in lower percentage of β-crystal in the blends than that in neat iPP under the same constant shear conditions. SAXS experiments revealed that shear flow could induce formation of oriented lamellae in iPP and iPP in the blends, and the presence of EPDM led to a reduced fraction of oriented lamellae.

关键词： Shear-induced crystallization Polypropylene EPDM Blends β-Crystal

Blue electroluminescence of a novel Zn^(2+)–β-diketone complex with a carbazole moiety

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Chinese Chemical Letters 2014年第1期25卷 69-72页

作者： Jian Liu jing-sheng Miao School of New Energy Science and Engineering Xinyu University Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and DevicesSouth China University of Technology

In this letter, a novel zinc complex of Zn（ECTFBD）2 was synthesized by an environment-friendly grinding technique in high yield. Its structure was confirmed by 1H NMR, MS and EA. HECTFBD is 1-（9-ethyl-9H- carbazol-3-yl）-4,4,4-trifluorobutane-l,3-dione. Zn（ECTFBD）2-based light-emitting devices were fabricated. The architecture of the devices was ITO/PEDOT （40 nm）/100 wt% PVK： 40 wt% OXD-7： x wt% Zn（ECTFBD）2 （85 nm）/CsF （1.5 nm）/Al （100 rim）, where x = 1, 5, and 10 （relative to the mass of PVK and OXD-7）. The three devices displayed blue emissions with peaks at 450, 458, and 460 nm, respectively. A maximum luminous efficiency of 0.86 cd/A and a luminance of 228 cd/m2 were achieved by the 1 wt% doped device. So, we demonstrated further that Zn2＋-β-diketone complexes can be effectively severed as a class of new electroluminescent materials. In addition, the thermal stability of Zn（ECTFBD）2 was tested and the UV-vis and photoluminescent behaviors of Zn（ECTFBD）2 in CH2CI2 were investigated.

关键词： Zinc complex Blue electroluminescence β-Diketone Carbazolemoiety

In-line Plasma-induced Graft-copolymerization of Pentaerythritol Triacrylate onto Polypropylene

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Chinese Journal of Polymer Science 2018年第8期36卷 979-983页

作者： Gui-Qiu Ma Guan-Kai Sun Zhe Ma jing-Qing Li jing sheng Department of Polymer Material Science and Engineering Institute of Advanced Polymer MaterialsSchool of Material Science and EngineeringTianjin Key Laboratory of Composite and Functional MaterialsTianjin University

Pentaerythritol triacrylate （PETA） was successfully grafted onto the plasma-treated isotactic polypropylene （iPP） via the in situ melt processing. The X-ray photoelectron spectroscopy （XPS） results showed that the hydroxyl and carbonyl groups, and peroxides could be generated via plasma treatment. The content of free radical in plasma-treated iPP （PiPP） was measured by 2,2-diphenyl-1- picrylhydrazyl （DPPH）. It was found that the resulting peroxides induced the grafting copolymerization of PETA onto iPP, and the grafted PETA promoted the formation of β-crystal in PiPP, which was evidenced by Fourier transform infrared spectroscopy （FTIR）, differential scanning calorimetry （DSC） and wide-angle X-ray diffraction （WAXD） measurements, respectively.

关键词： Plasma treatment Melt processing Graft copolymerization Pentaerythritol triacrylate

Clustering properties of partly charged superfine particles in a light medium

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Chinese Chemical Letters 2007年第11期18卷 1419-1422页

作者： jing sheng Li Juan Wang Qin Shen School of Chemistry and Chemical Engineering Jiangsu University 301 Xue Fu Road Zhenjiang 212013 China

This paper investigated average cluster sizes （ACS） and cluster size distributions （CSD） at different shear rates by Brownian dynamics in non-, bi-, and uni-polar systems with partly charged superfine particles, The investigation indicates that clusters in non- polar systems are the weakest and easiest to be damaged by increasing shear stresses; charged particles play important and different roles： in bi-polar system, it intends to strengthen clusters to some extent provided that the sign-like ions homogeneously arranged; in uni-polar system charged particles cracked the clusters into smaller ones, but the small clusters are strong to stand with larger shear stress. The relationship between ACS and shear rates follows power law with exponents in a range 0.18-0.28, these values are in a good agreement with experiment range but at the lower limit compared with other systems of non-metallic cluster particles.

关键词： Partly charged particles Average cluster sizes Cluster size distributions

Chemical-physical aspects of formation and evolution of phase structure in multi-polymers: Intensity fluctuation, phase structure and its fractal characteristics in blends of isotactic polypropylene with poly(cis-1,4-butadiene) rubber

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Science China Chemistry 2012年第5期55卷 854-864页

作者： MA GuiQiu YANG YuPing HUANG DingHai sheng jing School of Materials Science and Engineering Tianjin University Tianjin 300072 China Tianjin Key Laboratory of Composite and Functional Materials Tianjin 300072 China

This paper studies the formation and evolution of phase structure of isotactic polypropylene/poly（cis-1,4-butadiene）（iPP/PCBR） blends during molten and mixing in a visual mixer by on-line analysis of the small angle light back scattering. The density fluctuation of iPP/PcBR blends during molten and mixing is discussed using the integral-intensity Js, of the scattering intensity of the blends. The ＂invariant＂ Q, which shows fluctuation of the system, is calculated by data of the small angle light back scattering, and the variation of Q with the blending time, temperature and shear rate during molten and mixing in iPP/PcBR blends is discussed. The structure parameters which characterize dimensions of phase in the blends, as the correlation distance ac, and the average chord lengths of two-phase, as lipp and lPcBR, are calculated by data of scattering intensity. The average diameters dp of dispersed phases are calculated from SEM images. The variation of ac, dp, lipp and lPcBR with the blending time and compositions in the blends during molten and mixing is discussed. The scale law is analyzed to find multi-scale char- acteristics in this system. The generalized fractal dimension Dp is calculated and the relation of Dp with generalized entropy function is discussed to determine that Dp is state function and the physical significance of Dp is the same as that of the generalized entropy function. polymer blends, on-line analysis, fractal, polypropylene

关键词： polymer blends on-line analysis fractal polypropylene

Effects of post-heading high temperature on some quality traits of malt barley

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Journal of Integrative Agriculture 2020年第11期19卷 2674-2679页

作者： NI sheng-jing ZHAO Hui-fang ZHANG Guo-ping Department of Agronomy College of Agriculture and BiotechnologyZhejiang UniversityHangzhou 310029P.R.China

Global change is bringing barley with more frequency of suffering from high ***,little has been known about the influence of high temperature on malt quality *** this study,we investigated the impact of 1-wk heat stress(32°C/26°C,day/night,12 h/12 h)initiating from the 7th(HT7)and 14th(HT14)days after heading on some grain and malt quality traits of two barley *** comparison with normal temperature(24°C/18°C,day/night,12 h/12 h),heat stress significantly reduced kernel weight,seed setting rate and grains per spike:HT7 having a larger effect than ***,total protein andβ-glucan contents,andβ-amylase and limit dextrinase activities were significantly increased under high temperature,with HT7-treated plants showing larger ***,the different changes of four protein fractions under heat stress were found in the two barley cultivars,indicating the possibility of breaking positive association between protein content and enzyme activity.

关键词： barley β-glucan β-amylase heat stress limited dextrinase protein

A New Type of Seiberg-Witten Map and Its Application

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Communications in Theoretical Physics 2008年第11期50卷 1077-1080页

作者： GUAN Yong LIN Bing-sheng jing Si-Cong Department of Modern Physics University of Science and Technology of China Hefei 230026 China

Deformation quantization is a powerful tool to deal with systems in noncommutative space to get their energy spectra and corresponding Wigner functions, especially for the ease of both coordinates and momenta being noneommutative. In order to simplify solutions of the relevant .-genvalue equation, we introduce a new kind of Seiberg Witten-like map to change the variables of the noncommutative phase space into ones of a commutative phase space, and demonstrate its role via an example of two-dimensional oscillator with both kinetic and elastic couplings in the noneommutative phase space.

关键词： deformation quantization noncommutative phase space coupled oscillator

Zn-air batteries for electric vehicles

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Tungsten 2024年第1期6卷 164-173页

作者： Nai-Qi Meng Yu-Xin Fan jing-sheng Cai State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China College of Energy Soochow Institute for Energy and Materials InnovationS(SIEMIS)Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu Province Soochow UniversitySuzhou 215006China Institute of New Energy for Vehicles School of Materials Science and EngineeringTongji UniversityShanghai 201804China

The increasingly serious environmental challenges have gradually aroused people's interest in electric *** the last decade,governments and automakers have collaborated on the manufacturing of electric vehicles with high ***-edge battery technologies are pivotal for the performance of electric ***-air batteries are considered as potential power batteries for electric vehicles due to their high ***-air battery researches can be classified into three categories:primary batteries,mechanically rechargeable batteries,and chemically rechargeable *** majority of current studies aim at developing and improving chemically rechargeable and mechanically rechargeable Zn-air *** have tried to use catalytic materials design and device design for Zn-air batteries to make it possible for their applications in electric *** review will highlight the state-of-the-art in primary batteries,mechanically rechargeable batteries,and chemically rechargeable batteries,revealing the prospects of Zn-air batteries for electric vehicles.

关键词： Energy storage Electric vehicles Bifunctional oxygen catalysts Mechanically rechargeable Zn-air batteries Chemically rechargeable Zn-air batteries

Air Plasma-Activated Crosslinking of Low-Density Polyethylene During Melt Mixing

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Transactions of Tianjin University 2020年第1期26卷 33-39页

作者： Yangfeng Cui Zhe Ma Guiqiu Ma jing sheng School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional Materials Tianjin University

In this work,air plasma surface treatment followed by oxidation in an atmospheric environment was used to generate activated low-density polyethylene(LDPE)with oxygen-containing functional groups and peroxide *** resulting samples were then studied by using attenuated total internal reflectance-Fourier-transform infrared spectroscopy,X-ray photoelectron spectroscopy,and the 2,2-diphenyl-1-picrylhydrazyl *** radicals are generally considered active substances which can initiate the crosslinking *** mixing of the surface-treated LDPE allowed activated polymer chains with peroxide radicals to initiate the crosslinking reaction,and the maximum gel fraction obtained was 4.1%.The rheological behaviors,including viscosity,storage and loss moduli,loss tangent,and Cole-Cole plots,of the slightly crosslinked LDPE were studied,and the results of tensile experiments revealed that the formation of slightly crosslinked structures can improve yield and fracture stresses without sacrificing the breakage strain.

关键词： Air plasma Slight crosslinking Rheological behaviors Mechanical properties