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PARTIAL CARBAMOYLATION OF CELLULOSE MICROSPHERES: A NEW METHOD TO PREPARE ADSORBENTS FOR LIQUID CHROMATOGRAPHY

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Chinese Journal of Polymer Science 2013年第12期31卷 1725-1732页

作者： Wei Chen Qin Bin 柏正武周兴平 xiao-lin xie Key Lab for Large-Format Battery Materials and Systems Ministry of EducationSchool of Chemistry and Chemical EngineeringHuazhong University of Science and Technology Key Lab of Green Chemical Process Ministry of EducationHubei Key Laboratory of Novel Chemical Reactor and Green Chemical TechnologyWuhan Institute of Technology

Micron-sized cellulose microspheres were prepared through sol-gel method using NaOH/urea solution to dissolve cellulose, then cross-linked by 1,6-hexanylene diisocyanate （HDI）, toluene 2,4-diisocyanate （TDI） and 1,4-phenylene diisocyanate （PDI）, respectively. The reaction conditions for partial modification of the microspheres were studied. The degree of substitution （DS） in cellulose was controlled by adjusting the reaction conditions. HDI-crosslinked microspheres were partially modified with phenyl isocyanate to obtain chiral stationary phases （CSPs）. The CSPs of a lower degree of crosslinking （DC） showed better chiral recognition ability than those of a higher DC. Meanwhile the CSPs prepared by pre- modification exhibited better chiral recognition ability than those prepared by pre-crosslinking.

关键词： Cellulose Microspheres Functionalization Chiral stationary phase Chiral recognition.

Improving amplify-and-forward relay selection algorithm based on partial relay link

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The Journal of China Universities of Posts and Telecommunications 2010年第1期17卷 56-61页

作者： WANG Fei-fei LIU Yuan-an lin xiao-feng xie Gang Key Labomty of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

This article addresses the design problem of selecting an appropriate relay in amplify-and-forward （AF） cooperative diversity systems. In this regard, this article focuses on relay selection based on partial channel knowledge only across the source and relay links. In particular, the two fundamental questions will be answered, that is, whether to cooperate and whom to cooperate with. Through answering these two questions, an improved relay selection strategy based on partial relay link, which emphasizes that cooperation happens when necessary, is proposed to aim at maximizing the average mutual information. Then a joint optimization, in terms of power allocation and relay selection, is employed to guarantee a robust performance for relay selection based on partial relay link. Optimum power is allocated between the source and the selected relay to maximize the output signal-to-noise （SNR） at the destination. Simulation results turn out that the improved scheme can achieve better performance than previous work and the robust performance can be guaranteed by employing joint optimization.

关键词： cooperative diversity amplify-and-forward relay relay selection average mutual information

CO_(2)-based Biodegradable Supramolecular Polymers with Well-tunable Adhesive Properties

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Chinese Journal of Polymer Science 2022年第1期40卷 47-55页

作者： xiao-Jing Li Ying-Feng Wen Yong Wang Hai-Yan Peng Xing-Ping Zhou xiao-lin xie Key Laboratory for Material Chemistry of Energy Conversion and Storage Ministry of EducationSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Supramolecular adhesives that enable debonding on-demand are of significant research interest for the development of adaptive and smart materials,yet,biodegrable supramolecular adhesives have been rarely ***,telechelic,three-armed and four-armed CO_(2)-based polyols with close molecular weights and various content(or carbonate unite content)have been synthesized via a zinc-cobalt double metal cyanide complex catalyzed ring-opening copolymerization of CO_(2) and propylene oxide,and further exploited as sustainable and biodegradable building blocks for supramolecular polymers(SMPs)with 2-ureido-4[1H]-pyrimidinone(UPy)***,the orthogonal modulation of the CO_(2) content and the topology of CO_(2)-based polyols provide a unique opportunity to fine-tune the surface energy as well as the cohesive strength of the resulting CO_(2)-based ***,a three-armed SMP with 44%CO_(2)(3UPy-CO_(2)-44%)can well balance the trade-off between surface energy and cohesive strength,therefore bestowing a high adhesive strength of 7.5 and 9.7 MPa towards stainless steel and wood substrates respectively by testing the corresponding single lap ***,the light-responsive adhesion property of 3UPy-CO_(2)-44%has been demonstrated exemplarily by blending with a UV sensitizer.

关键词： Biodegradable polymer Adhesive CO_(2)-based polyol ROCOP Supramolecular polymer

Visible Light and Temperature Regulated Reflection Colors in Self-supporting Cholesteric Liquid Crystal Physical Gels

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Chinese Journal of Polymer Science 2021年第12期39卷 1617-1625页

作者： Dong-Xu Zhao Qian Jiang Jing Wang Yuan Qiu Yong-Gui Liao xiao-lin xie Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Engineering Research Center for Biomaterials and Medical Protective MaterialsHubei Key Laboratory of Materials Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Material Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan 430074China

Photo-responsive cholesteric liquid crystals(CLCs)have attracted much attention in recent years due to their wide applications in filters,tun able optical lasers,dyn amic display devices,***,UV light is usually used as the exter nal stimulus source,which is not envir on ment-frie ndly *** the other hand,the mecha nical properties of CLCs are not strong eno ugh for these practical ***,it still remains a challenge to endow the CLCs with visible light response and high mechanical properties at the same ***,an axially chiral tetra-fluorinated binaphthyl azobenzene gelator(S-4F-AG)is *** 550 and 450 nm light irradiations,S-4F-AG exhibits excellent photo-switchable ***,the maximum con tent of c/s-isomer and its half-life are as high as 35%and 89 h in acet on itrile,respectively.A self-supporting CLC physical gel with a storage modulus around 104 Pa can be obtained when 3wt%S-4F-AG and 12wt%binaphthyl azobenzene derivative(dopant 2)are co-doped into a nematic LC host *** CLC physical gel exhibits a temperature-driven blue,green,and red reflection colors ***,such three primary RGB colors can also be realized by adjusting the exposure time of 550 nm green *** work lays a solid foundation for the applications ranging from information storage to high-tech anticounterfeit.

关键词： Cholesteric liquid crystal Gel Visible light response Reflect!on color Self-supporting ability

Gas-based reduction of vanadium titano-magnetite concentrate:behavior and mechanisms

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International Journal of Minerals,Metallurgy and Materials 2017年第1期24卷 10-17页

作者： Yu-lei Sui Yu-feng Guo Tao Jiang xiao-lin xie Shuai Wang Fu-qiang Zheng School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China

The reduction of vanadium titano-magnetite pellets by H_2-CO at temperatures from 850 to 1050°C was investigated in this paper. The influences of pre-oxidation treatment, reduction temperature, and V_（H_2）/（V_（H_2）＋ VCO） on the metallization degree were studied. The results showed that pre-oxidation played a substantial role in the reduction of vanadium titano-magnetite pellets. During the reduction process, the metallization degree increased with increasing temperature and increasing V_（H_2） /（V_（H_2）＋ VCO）. The phase transformation of pre-oxidized vanadium titano-magnetite pellets during the reduction process under an H_2 atmosphere and a CO atmosphere was discussed, and the reduced samples were analyzed by scanning electron microscopy（SEM） in conjunction with back scatter electron（BSE） imaging. The results show that the difference in thermodynamic reducing ability between H_2 and CO is not the only factor that leads to differences in the reduction results obtained using different atmospheres. Some of Fe_（3-x）Ti_xO_4 cannot be reduced under a CO atmosphere because of the densification of particles＇ structure and because of the enrichment of Mg in unreacted cores. By contrast, a loose structure of particles was obtained when the pellets were reduced under an H_2 atmosphere and this structure decreased the resistance to gas diffusion. Moreover, the phenomenon of Mg enrichment in unreacted cores disappeared during H_2 reduction. Both the lower resistance to gas diffusion and the lack of Mg enrichment facilitated the reduction of vanadium titano-magnetite.

关键词： titano-magnetite ore reduction behavior mechanisms

Holographic Polymer Nanocomposites with High Refractive Index Modulation by Doping Liquid Crystal E6M

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Chinese Journal of Polymer Science 2024年第7期42卷 926-935,I0006页

作者： Meng-Yun Wang Yue Zhang Dan Wang Ming Yao Yi-Xuan Wang Xing-Ping Zhou Hai-Yan Peng xiao-lin xie Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074China State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan430074China National Anti-counterfeit Engineering Research Center Huazhong University of Science and TechnologyWuhan430074China

Holographic optical elements(HOEs)based on polymer composites have become a research hot spot in recent years for augmented reality(AR)due to the significant improvement of optical performance,dynamic range,ease of processing and high yield ***,it remains a formidable challenge to obtain a large field of view(FOV)and brightness due to the limited refractive index ***,we report an effective method to tackle the challenge by doping an epoxy liquid crystal termed E6M,which enables a large refractive index modulation of 0.050@633 nm and low haze of 5.0%at a doping concentration of 5 wt%.This achievement may be ascribed to the improved molecular ordering of liquid crystals within the holographic polymer *** high refractive index modulation can endow transmission-type holographic polymer composites with a high diffraction efficiency of 96.2%at a small thickness of 5μm,which would promise the design of thin and lightweight AR devices.

关键词： Polymer nanocomposites Holography AR/VR Refractive index modulation Liquid crystal

P - glycoprotein restricted transport of nimodipine across the blood - brain barrier

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P - glycoprotein restricted transport of nimodipine across t...

第八届全国生化药理学术讨论会暨第七届Servier奖颁奖大会会议

作者： ZHANG Li LIU xiao - dong xie lin WANG Guang - ji

P-glycoprotein (P-gP) located in brain capillary endothelial cell membranes has been thought to function as a component of the blood-brain barrier (BBB). Nimodipine (NMD) was a calcium antagonist of dihydropyridine and was successfully used to treat central nervous system disorders. Because NMD is also a substrate of P-gp, which suggested that NMD transports across BBB may be modulated by P-gp. In this study, the uptake and efflux of NMD by primary cultured rat brain capillary endothelial cells (BCEC) were investigated in order to examine whether the transport of NMD from the

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全息聚合物分散液晶的结构调控与性能

高分子学报 2017年第10期27卷 1557-1573页

作者：倪名立彭海炎解孝林华中科技大学化学与化工学院能量转换与存储材料化学教育部重点实验室武汉430074

全息聚合物分散液晶(HPDLCs)是由富聚合物相与富液晶相周期性排列而成的结构有序高分子复合材料.HPDLCs通过单体/液晶复合体系的光聚合诱导相分离而形成,如何调控并定量化描述复合体系的光聚合反应动力学、凝胶化行为和相分离程度,进而... 详细信息

全息聚合物分散液晶(HPDLCs)是由富聚合物相与富液晶相周期性排列而成的结构有序高分子复合材料.HPDLCs通过单体/液晶复合体系的光聚合诱导相分离而形成,如何调控并定量化描述复合体系的光聚合反应动力学、凝胶化行为和相分离程度,进而获得结构规整、电光性能优异的HPDLCs是关键难题.专论概述了光引发体系、单体结构、纳米无机材料掺杂对HPDLCs结构及性能的影响.光引发阻聚剂通过引发和阻聚的竞争与协同,降低了光聚合反应速率、延迟了凝胶时间,促进形成衍射效率达90%的HPDLCs.超支化单体降低了复合体系黏度和光聚合反应速率,延迟了凝胶时间,促使形成衍射效率达94%、具有一维光子晶体结构的HPDLCs.丙烯酰胺单体优化了相分离结构,将HPDLCs的衍射效率提升至98%.纳米硫化锌掺杂在保持规整结构和高衍射效率的同时,大幅降低了HPDLCs的驱动电压.研究还确定了HPDLCs的相分离程度与凝胶时间的函数关系.构建兼具高衍射效率与低驱动电压的HPDLCs,推进其在彩色3D图像存储等领域的应用仍是重要课题.

关键词：聚合物分散液晶全息光聚合相分离图像存储

Characteristics of gut microbiota dysbiosis in patients with colorectal polyps

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 13-21页

作者： Xian-Rong Wu xiao-Hong He Yong-Fang xie School of Life Health Information Science and Engineering Chongqing Post and Communications UniversityChongqing 400065China

This editorial,inspired by a recent study published in the World Journal of Gastrointestinal Oncology,covers the research findings on microbiota changes in various *** recurrent colorectal polyps,the abundances of Klebsiella,Parvimonas,and Clostridium increase,while those of Bifidobacterium and Lactoba-cillus *** dysbiosis may promote the formation and recurrence of *** microbial changes have also been observed in colorectal cancer,inflammatory bowel disease,autism spectrum disorder,and metabolic syndrome,indicating the role of increased pathogens and decreased probiotics in these *** the gut microbiota,particularly by increasing probiotic levels,may help prevent polyp recurrence and promote gut *** microbial intervention strategy holds promise as an adjunctive treatment for patients with colorectal polyps.

关键词： Recurrent colorectal polyps Gut microbiota dysbiosis Klebsiella Probiotics Intestinal inflammation Microbial intervention strategy