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Synthesis of a New Asymmetrical Ether Diamine with Aromatic Structure and Related Polyimide

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Chinese Chemical Letters 2006年第5期17卷 635-636页

作者： Yu SHAO Yah Feng LI Xiao Long WANG shu Jiang zhan Xin zhao Tao MA State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou 730000

A new aromatic asymmetrical ether diamine, 1,4-bis（3＇,4’-diaminophenoxy）benzene 3 was synthesized in three steps, using hydroquinone as starting material. A new aromatic polyimide containing asymmetrical diaryl ether segments was prepared from the resulting diamine with 4,4＇-oxydiphthalic anhydride （ODPA） via a conventional two-step thermal or chemical imidization method. The resulting polyimide exhibits high thermal resistance, excellent solubility, film-forming capability, high mechanical strength and modulus.

关键词： Polyimide asymmetrical ether diamine aromatic polyimide.

B2-CuZr reinforced amorphous alloy matrix composites:A review

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China Foundry 2025年第1期22卷 1-11页

作者： Wei Guo Run-hua Huang Zhen zhang Mi zhao Jin-cheng Wang Yan-qiang Qiao shu-lin Lü shu-sen Wu State Key Lab of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan 430074China Research Institute of Huazhong University of Science and Technology in Shenzhen Shenzhen 518057GuangdongChina

B2-CuZr phase reinforced amorphous alloy matrix composites has become one of the research hotspots in the field of materials science due to the“transformation-induced plasticity”phenomenon,which makes the composites show better macroscopic plastic deformability and obvious work-hardening behavior compared to the conventional amorphous alloy matrix composites reinforced with ductile ***,the in-situ metastable B2-CuZr phase tends to undergo eutectoid decomposition during solidification,and the volume fraction,size,and distribution of B2-CuZr phase are difficult to control,which limits the development and application of these *** date,much efforts have been made to solve the above problems through composition optimization,casting parameter tailoring,and post-processing *** this study,a review was given based on relevant studies,focusing on the predictive approach,reinforcing mechanism,and microstructure tailoring methods of B2-CuZr phase reinforced amorphous alloy matrix *** research focus and future prospects were also given for the future development of the present composite system.

关键词： amorphous alloy matrix composite B2-CuZr phase plasticity microstructure tailoring

Digital Industry Agglomeration and Export Product Diversification:Evidence from Chinese Firms

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China & World Economy 2025年第1期33卷 64-100页

作者： Jinyong zhan Xinrui Wang Qian Li Jiazhang zhao School of Economics Capital University of Economics and BusinessChina School of Economics and Management Tsinghua UniversityChina

The rapid development of digital industries such as artificial intelligence and big data has fundamentally transformed production, providing new opportunities for the diversification of firms. Drawing on data from the China Customs Database and the Annual Survey of Industrial Firms for 2003–2013, we employed a panel fixed effects model to examine the impact of digital industry agglomeration on firms' export product diversification. The findings revealed that, holding other conditions constant, a one-unit increase in digital industry agglomeration resulted in a significant 2.34 percent rise in export scope and a significant decrease by 0.58 percent in export concentration. Firms in digitally advanced cities and capital-intensive industries were more influenced by digital industry agglomeration in export diversification. Mechanism analysis reveals that digital industry agglomeration fostered export product diversification through innovation stimulation, information dissemination, and efficiency enhancement. Innovation was evidenced by increases in urban innovation indices and the emergence of new export products. Information dissemination boosted wholesale and retail sales, helping firms to expand export destinations. Efficiency enhancement was reflected in narrowing management efficiency gaps among firms.

关键词： digital economy export diversification industry agglomeration innovation

Significant spatiotemporal pattern of nitrous oxide emission and its influencing factors from a shallow eutropic lake in Inner Mongolia,China

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Journal of Environmental Sciences 2025年第3期149卷 488-499页

作者： Guohua Li Sheng zhang Xiaohong Shi Shengnan zhao Liyang zhan Xueru Pan Fan zhang Haifeng Yu Yue Sun Lauri Arvola Jussi Huotari Water Conservancy and Civil Engineering College Inner Mongolia Agricultural UniversityHohhot 010018China Inner Mongolia Water Resource Protection and Utilization Key Laboratory Hohhot 010018China State Gauge and Research Station of Wetland Ecosystem Wuliangsuhai LakeBayan Nur 014404China Key Laboratory of Global Change and Marine-Atmospheric Chemistry Third Institute of OceanographyMinistry of Natural ResourcesXiamen 361005China Faculty of Biological and Environmental Sciences Ecosystems and Environment Research ProgrammeLammi Biological StationUniversity of HelsinkiLammi FI-16900Finland Masinotek Oy Ensimmainen Savu 2Vantaa FI-01510Finland

Eutrophic shallow lakes are generally considered as a contributor to the emission of nitrous oxide(N_(2)O),while regional and global estimates have remained *** due to a lack of data and insufficient understanding of the multiple contributing *** study characterized the spatiotemporal variability in N_(2)O concentrations and N_(2)O diffusive fluxes and the contributing factors in LakeWuliangsuhai,a typical shallow eutrophic and seasonally frozen lake in Inner Mongolia with cold and arid *** N_(2)O concentrations of the lake exhibited a range of 4.5 to 101.2 nmol/L,displaying significant spatiotemporal *** lowest and highest concentrations were measured in summer and winter,*** spatial distribution of N_(2)Ofluxwas consistent with that of N_(2)O ***,the hotspots of N_(2)O emissions were detected within close to the main inflow of *** wide spatial and temporal variation in N_(2)O emissions indicate the complexity and its relative importance of factors influencing emissions.N_(2)O emissions in different lake zones and seasons were regulated by diverse *** influencing the spatial and temporal distribution of N_(2)O concentrations and fluxes were identified as WT,WD,DO,Chl-a,SD and ***,the same factor demonstrated opposing effects on N_(2)O emission in various seasons or *** research improves our understanding of N_(2)O emissions in shallow eutrophic lakes in cold and arid areas.

关键词： Nitrous oxide Spatial and temporal variation Controlling factors Shallow lakes

Influence Factors on the Radiation Temperature Measurement Accuracy of Turbine Blades

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Journal of Thermal Science 2025年第02期 510-523页

作者： LI Xunfeng YAN Hao zhao shu'nan CHENG Keyong CHEN Junlin HUAI Xiulan Institute of Engineering Thermophysics Chinese Academy of Sciences School of Engineering Science University of the Chinese Academy of Sciences Nanjing Institute of Future Energy System

Backward Monte Carlo method of the complicated and exact three-dimensional turbine with the spectral emission and reflection characteristics of the turbine blades materials and the spectral absorption and emission characteristics of combustion gas is *** factors affecting the accuracy of the radiation temperature measurement are *** results show that reducing the distance from the probe to the target surface can reduce the effect of the environment on the measurement *** the temperature and emissivity of the target surface can improve the measurement *** reflection characteristics of the surfaces have little influence on the radiation temperature measurement,so the blades can be considered as diffuse reflectors in order to improve the calculation *** temperature measurement accuracy decreases rapidly as the temperature of the combustion gas *** temperature measurement accuracy decreases with the increase of total gas pressure and H2O *** measuring the temperature of rotating blades,the apparent emissivity of the target surface is inversely proportional to the measurement accuracy.

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Swelling and erosion assisted sustained release of tea polyphenol from antibacterial ultrahigh molecular weight polyethylene for joint replacement

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Chinese Chemical Letters 2025年第2期36卷 344-348页

作者： Yue Ren Kang Li Yi-Zi Wang Shao-Peng zhao shu-Min Pan Haojie Fu Mengfan Jing Yaming Wang Fengyuan Yang Chuntai Liu State Key Laboratory of Structural Analysis Optimization and CAE Software for Industrial EquipmentNational Engineering Research Center for Advanced Polymer Processing TechnologyZhengzhou University Department of Stomatology The First Affiliated Hospital of Zhengzhou University Tianjian Laboratory of Advanced Biomedical Sciences Academy of Medical SciencesZhengzhou University

The considerable hazard posed by periprosthetic joint infections underlines the urgent need for the rapid advancement of in-situ drug delivery systems within joint materials. However, the pursuit of sustained antibacterial efficacy remains a formidable challenge. In this context, we proposed a novel strategy that leverages swelling and erosion mechanisms to facilitate drug release of drug-loaded ultrahigh molecular weight polyethylene(UHMWPE), thereby ensuring its long-lasting antibacterial *** oxide(PEO), a hydrophilic polymer with fast hydrating ability and high swelling capacity, was incorporated in UHMWPE alongside the antibacterial tea polyphenol(epigallocatechin gallate,EGCG as representative). The swelling of PEO enhanced water infiltration into the matrix, while the erosion of PEO balanced the release of the encapsulated EGCG, resulting in a steady release. The behavior was supported by the EGCG release profiles and the corresponding fitted release kinetic *** demonstrated by segmented antibacterial assessments, the antibacterial efficiency was enhanced 2to 3 times in the PEO/EGCG/UHMWPE composite compared to that of EGCG/UHMWPE. Additionally, the PEO/EGCG/UHMWPE composite exhibited favorable biocompatibility and mechanical performance, making it a potential candidate for the development of drug-releasing joint implants to combat prosthetic bacterial infections.

关键词： Antibacterial Joint replacement PEO Tea polyphenol UHMWPE

Repetitive traumatic brain injury–induced complement C1–related inflammation impairs long-term hippocampal neurogenesis

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Neural Regeneration Research 2025年第3期20卷 821-835页

作者： Jing Wang Bing zhang Lanfang Li Xiaomei Tang Jinyu Zeng Yige Song Chao Xu Kai zhao Guoqiang Liu Youming Lu Xinyan Li Kai shu Department of Neurosurgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Neurosurgery Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Pathophysiology School of Basic Medicine and Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Institute for Brain Research Wuhan Center of Brain ScienceHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Graduate Student Chongqing Medical UniversityChongqingChina Department of Basic Medicine School of Medical ScienceHubei University for NationalitiesEnshiHubei ProvinceChina Department of Anatomy School of Basic Medicine and Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Repetitive traumatic brain injury impacts adult neurogenesis in the hippocampal dentate gyrus,leading to long-term cognitive ***,the mechanism underlying this neurogenesis impairment remains *** this study,we established a male mouse model of repetitive traumatic brain injury and performed long-term evaluation of neurogenesis of the hippocampal dentate gyrus after repetitive traumatic brain *** results showed that repetitive traumatic brain injury inhibited neural stem cell proliferation and development,delayed neuronal maturation,and reduced the complexity of neuronal dendrites and *** with repetitive traumatic brain injuryalso showed deficits in spatial memory ***,following repetitive traumatic brain injury,neuroinflammation was enhanced in the neurogenesis microenvironment where C1q levels were increased,C1q binding protein levels were decreased,and canonical Wnt/β-catenin signaling was *** inhibitor of C1 reversed the long-term impairment of neurogenesis induced by repetitive traumatic brain injury and improved neurological *** findings suggest that repetitive traumatic brain injury–induced C1-related inflammation impairs long-term neurogenesis in the dentate gyrus and contributes to spatial memory retrieval dysfunction.

关键词： complement C1 dendrite dentate gyrus hippocampus neural stem cell neurogenesis neuroinflammation neurological function neuron traumatic brain injury

Regulation of Yield and Eating and Cooking Quality in Rice Through Seed Albumin OsRAL5

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Rice science 2025年第1期32卷 6-10,I0010-I0016页

作者： zhao Chunfang HE Lei GUAN Ju LUO Lei zhao Ling ZHOU Lihui YAO shu CHEN Tao ZHU Zhen zhao Qingyong WANG Cailin zhanG Yadong Key Laboratory of Jiangsu Province for Agrobiology/East China Branch of National Center of Technology Innovation for Saline-Alkali Tolerant Rice/Institute of Food Crops Jiangsu Academy of Agricultural ScienceNanjing 210014China

Seed storage proteins and their abundance are closely related to the formation of rice quality and grain size.A better understanding of the molecular basis of seed storage proteins will provide important information for developing new rice breeding *** this study,we report that a seed storage protein albumin,named OsRAL5,positively regulates rice quality and grain ***5 is specifically expressed during the grain-filling stage,suggesting its key role in regulating seed *** editing of OsRAL5 using the CRISPR/Cas9 system diminished grain size and weight,resulting in the development of white-core endosperm and a reduction in eating and cooking quality(ECQ).Conversely,the endosperm appearance became transparent,and both grain weight and ECQ improved in the OsRAL5 over-expressed *** major seed storage components differed significantly between the OsRAL5-edited(dOsRAL5-TS)and OsRAL5-overexpressed(OsRAL5-OE)lines compared with the wild *** protein and total lipid contents both decreased in the dOsRAL5-TS lines and increased in the OsRAL5-OE ***,the over-expression of OsRAL5 significantly increased nutritional content and simultaneously improved yield and *** results imply that OsRAL5 might be a promising candidate gene for breeding super rice varieties with increased yield potential and superior quality.

关键词： CRISPR/Cas9 breeding Albumin

Cooperative maximum adhesion tracking control for multi-motor electric locomotives

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Railway Sciences 2025年第1期4卷 22-36页

作者： Leiting zhao Yongxiang Wang Kan Liu Liran Li Jingyuan zhan Qingliang Liu AC Transmission Department China Academy of Railway Sciences Corporation LimitedBeijingChina School of Information Science and Technology Beijing University of TechnologyBeijingChina

Purpose–This study aims to propose a cooperative adhesion control method for trains with multiple motors electric *** method is intended to optimize the output torque of each motor,maximize the utilization of train adhesion within the total torque command,reduce the train skidding/sliding phenomenon and achieve optimal adhesion utilization for each axle,thus realizing the optimal allocation of the multi-motor electric ***/methodology/approach–In this study,a model predictive control(MPC)-based cooperative maximum adhesion tracking control method for multi-motor electric locomotives is ***,train traction system with multiple motors is constructed in accordance with Newton’s second *** equations include the train dynamics equations,the axle dynamics equations,and the wheel-rail adhesion coefficient ***,a new MPC-based multi-axle adhesion co-optimization method is put *** method calculates the optimal output torque through real-time iteration based on the known reference slip speed to achieve multi-axle co-optimization under different ***–This paper presents a MPC system designed for the cooperative control of multi-axle *** results indicate that the proposed control system is able to optimize the adhesion of multiple axles under numerous different conditions and achieve the optimal power distribution based on the reduction of train skidding/***/value–This study presents a novel cooperative adhesion tracking control *** is designed for multi-motor electric locomotives,which has rarely been studied *** simulations are carried out in different conditions,including variable surfaces and motor failing.

关键词： Cooperative control Adhesion control Model predictive control Slip prevent Paper type Research paper