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Synthesis and Properties of Hydroxytelechelic Polyisobutylenes by End Capping with tert-Butyl-dimethyl-(4-methyl-pent-4-enyloxy)-silane

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Chinese Journal of Polymer Science 2019年第9期37卷 936-942页

作者： jing Li Kang-Da Wu Huang Shan jing-han zhang Ming Zhao Guang-Bi Gong Wen-Li Guo Yi-Bo Wu College of Materials Science & Engineering Beijing Institute of Petrochemical Technology Beijing 102617 China Lanzhou Petrochemical Research Center Petrochina Lanzhou 730060 China Beijing Key Laboratory of Specialty Elastomer Composite Materials Beijing Institute of Petrochemical Technology Beijing 102617 China

The low-activity cationic monomer tert-butyl-dimethyl-(4-methyl-pent-4-enyloxy)-silane was synthesized by Grignard reaction and hydroxyl-protection reaction. Living polyisobutylene chains were initially synthesized by controlled cationic polymerization and then capped with tert-butyl-dimethyl-(4-methyl-pent-4-enyloxy)-silane. The hydrolysis of these polyisobutylenes end capped with tert-butyl-dimethyl-(4-methyl-pent-4-enyloxy)-silane gave rise to hydroxytelechelic polyisobutylene. NMR analysis confirmed that the hydrolysis was complete. Results also showed that a low polymerization temperature favored the participation of tert-butyl-dimethyl-(4- methyl-pent-4?enyloxy)-silane in the end-capping reaction. Moreover, polyisobutylene-based polyurethane exhibited greater acid resistance than commercial polyurethane.

关键词： Carbocationic polymerization Polyisobutylene Hydrolysis Polyisobutylene-based polyurethane

Insight into the Excellent Tribological Performance of Highly Oriented Poly(phenylene sulfide)

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Chinese Journal of Polymer Science 2022年第3期40卷 290-298,I0007页

作者： Liang-Qing zhang Shu-Gui Yang jing-han zhang Ke-Peng Zhong Zhong-Guo Zhao Yan-Hui Chen Jun Lei Qiu-Yu zhang Zhong-Ming Li College of Material Science and Engineering Xi’an University of Science and TechnologyXi’an 710054China State Key Laboratory for Mechanical Behaviour of Materials Shaanxi International Research Center for Soft MaterialsXi’an Jiaotong UniversityXi’an 710049China School of Chemistry and Chemical Engineering Shaanxi Key Laboratory of Macromolecular Science and TechnologyKey Laboratory of Special Functional and Smart Polymer Materials of Ministry of Industry and Information TechnologyNorthwestern Polytechnical UniversityXi’an 710072China National and Local Engineering Laboratory for Slag Comprehensive Utilization and Environment Technology School of Materials Science and EngineeringShaanxi University of TechnologyHanzhong 723000China College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

Achieving low friction and wear of poly(phenylene sulfide)(PPS) without using fillers or blending is a challenging task, but one of considerable practical importance. Here we describe how neat PPS with high tribological performance is achieved by manipulating processing parameters(pressure, flow and temperature). The key to achieving high tribological performance is comparatively high molecular chain orientation, realized in neat PPS, at high shear rates and low pressure. The friction coefficient and wear rate are as low as ~0.3 and~10^(-6) mm^(3)·N^(-1)·m^(-1), respectively, which break the record for neat PPS. These values are even better than those for PPS-based blends and comparable to PPS composites. Further studies show, for the first time, that wear rate decreases exponentially with increasing molecular chain orientation, prompting us to revise the classical Archard's law by including the effect of molecular chain orientation. These findings open the possibility of using neat PPS in highly demanding tribological applications.

关键词： Poly(phenylene sulfide) Orientation Wear rate Frication coefficient Processing parameters

Studies on Combination of Flow Injection and Microwave Plasma Torch-Atomic Emission Spectrometry

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Chemical Research in Chinese Universities 1993年第3期9卷 246-247页

作者： YE Dong-mei, ZHAO jing-hong, zhang han-qi and JIN Qin-han (Department of Chemistry, Jilin University, Changchun, 130023)DONG De-fan (Hebei College of Geology, Shijiazhuang, 050031)

Although the flow injection(FI) as a sample introduction technique has been extensively applied to atomic spectrometry, such as ICP-AES and AAS, very little has been done so far on coupling FI to microwave plasma syst... 详细信息

关键词： Microwave plasma torch Flow injection Atomic emission spectrometry

游客感知价值对TCM评估游憩价值影响的介入方式比较研究——以湖南张谷英村为例

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旅游科学 2016年第5期30卷 24-36页

作者：韩静张茵南京大学地理与海洋科学学院江苏南京210023 北京林业大学园林学院北京100083

游憩价值评估是识别旅游资源经济价值的重要手段。TCM作为传统评估方法,其评估结果的准确性受多种因素影响,其中游憩需求的影响因素对评估结果的影响是尚待解决的关键问题。游客感知价值是影响游憩需求的重要因素,考察其对评估结果的影... 详细信息

游憩价值评估是识别旅游资源经济价值的重要手段。TCM作为传统评估方法,其评估结果的准确性受多种因素影响,其中游憩需求的影响因素对评估结果的影响是尚待解决的关键问题。游客感知价值是影响游憩需求的重要因素,考察其对评估结果的影响是提高评估结果精确性的一种有益尝试。本文以TCM的两种基本模型ZTCM和ITCM为基础,探索不同介入方式下感知价值对评估结果的影响机制。研究表明:感知价值作为自变量介入ZTCM模型后使人均消费者剩余下降了7.3%、游憩价值下降了4.4%,大于它作为中介变量介入ITCM模型后对评估结果的影响,说明感知价值主要通过与旅行花费共同作用对价值评估结果产生影响。这不仅揭示了游客感知价值影响的复杂性,更体现了游憩价值评估体系中考虑游憩需求影响因素的必要性。

关键词：游憩价值评估感知价值分区旅行费用法(ZTCM) 个人旅行费用法(ITCM) 中介变量自变量

Highly conductive and stable iodine doped argyrodite electrolyte for all-solid-state lithium batteries

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Journal of Energy Chemistry 2025年第1期100卷 50-58页

作者： Gaozhan Liu jing zhang jing Yang jinghui Chen Xingyue Xiao Xiayin Yao Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences

Lithium argyrodites with high ionic conductivity and low cost are considered as one of the most prospective solid electrolytes for all-solid-state lithium ***,the poor chemical stability and compatibility with lithium metal limit their ***,Li5.4PS4.4Cl1.4I0.2solid electrolyte with high ionic conductivity of 11.49 m S cm-1and improved chemical stability is synthesized by iodine *** ultra-thin Li5.4PS4.4Cl1.4I0.2membrane with thickness of 10μm can be obtained by wet coating process,exhibiting a high ionic conductivity of 2.09 mS cm-1and low areal resistance of 1.17Ω***,iodine doping could in-situ form LiI at the lithium/electrolyte interface and improve the critical current density of Li5.4PS4.4Cl1.6from 0.8 to 1.35 mA *** resultant LiCoO2/Li5.4PS4.4Cl1.4I0.2/Li battery shows excellent cycling stability at 1 C,with a reversible specific capacity of 110.1 mA h g-1and a retention of 80.5% after 1000 *** addition,the assembled LiCoO2/Li5.4PS4.4Cl1.4I0.2membrane/Li pouch cell delivers an initial discharge capacity of 110.4 mA h g-1and 80.5% capacity retention after 100 cycles.

关键词： Argyrodite electrolytes Iodine doping Ionic conductivity Stability All-solid-state lithium battery

Dielectric-ion-conductive ZnNb2O6 layer enabling rapid desolvation and diffusion for dendrite-free Zn metal batteries

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Journal of Energy Chemistry 2025年第1期100卷 693-701页

作者： Haifeng Yang Jian Wang Panpan zhang Xiaomin Cheng Qinghua Guan jing Dong Bixian Chen Lujie Jia jing zhang Yongzheng zhang Yunjian Liu Hongzhen Lin School of Materials Science and Engineering Jiangsu University i-Lab & CAS Key Laboratory of Nanophotonic Materials and Devices Suzhou Institute of Nano-Tech and Nano-Bionics Chinese Academy of Sciences Helmholtz Institute Ulm (HIU) Karlsruhe Institute of Technology (KIT) School of Materials Science and Engineering Xi'an University of Technology State Key Laboratory of Chemical Engineering East China University of Science and Technology

Rechargeable aqueous zinc-metal batteries （AZMBs） are promising candidates for large-scale energy storage systems due to their low cost and high ***,their performance and sustainability are significantly hindered by the sluggish desolvation kinetics at the electrode/electrolyte interface and the corresponding hydrogen evolution reaction where active water molecules tightly participate in the Zn（H2O）62+solvation ***,learnt from self-generated solid electrolyte interphase （SEI） in anodes,the dielectric but ion-conductive zinc niobate nanoparticles artificial layer is constructed on metallic Zn surface （ZNB@Zn）,acting as a rapid desolvation *** zincophilic and dielectric-conductive properties of ZNB layer accelerate interfacial desolvation/diffusion and suppress surface corrosion or dendrite formation,achieving uniform Zn plating/stripping behavior,as confirmed by electronic/optical microscopies and interface spectroscopical measurements together with theoretical ***,the as-prepared ZNB@Zn electrode exhibits excellent cycling stability of over 2000 h and robust reversibility （99.54%） even under high current density and depth of discharge ***,the assembled ZNB@Zn-based full cell displays high capacity-retention rate of 80.21%after 3000 cycles at 5 A g-1and outstanding rate performance up to 10 A *** large-areal pouch cell is stabilized for hundreds of cycles,highlighting the bright prospects of the dielectric but ion-conductive layer in further application of AZMBs.

关键词： Zn metal battery Dielectric artificial layer Rapid ion diffusion Zincophilic diffusion Active water inhibition

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基于分数傅里叶变换的二维工程图水印算法

计算机工程与应用 2010年第11期46卷 95-97页

作者：康菁菁张汗灵湖南大学计算机与通信学院长沙410082

提出一种基于离散分数傅里叶变换(DFRFT)的二维工程图数字水印算法。该算法分块提取工程图中线段的相对坐标线构造复值信号量,将水印嵌入复值信号量的分数傅里叶变换频谱(FRT)中。实验表明,该算法对平移、旋转、缩放、部分实体删除或添... 详细信息

提出一种基于离散分数傅里叶变换(DFRFT)的二维工程图数字水印算法。该算法分块提取工程图中线段的相对坐标线构造复值信号量,将水印嵌入复值信号量的分数傅里叶变换频谱(FRT)中。实验表明,该算法对平移、旋转、缩放、部分实体删除或添加等攻击具有良好的鲁棒性,同时具有良好的安全性。

关键词：数字水印离散分数傅里叶变换二维工程图

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芬兰职业教育发展：历史、现状与趋势

职业技术教育 2016年第21期37卷 64-68页

作者：韩静张力跃浙江师范大学金华321004 浙江师范大学职业教育研究中心

芬兰教育以拥有广泛的受教育人群而闻名于世,其职业教育经历了缘起、初步发展以及勃兴等阶段,在形成自身特色的同时,也面临着职业教育辍学率高,生源数量难以保证,职业教育向劳动力市场过渡过程中对劳动者要求不断提高等时代挑战,芬兰政... 详细信息

芬兰教育以拥有广泛的受教育人群而闻名于世,其职业教育经历了缘起、初步发展以及勃兴等阶段,在形成自身特色的同时,也面临着职业教育辍学率高,生源数量难以保证,职业教育向劳动力市场过渡过程中对劳动者要求不断提高等时代挑战,芬兰政府在普职融通、职业教育培养目标、职业教育资金支持以及职业教育地位方面采取措施积极应对挑战,使芬兰职业教育朝着制度化的轨道迈进。

关键词：职业教育芬兰历史挑战趋势

Unraveling brain aging through the lens of oral microbiota

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Neural Regeneration Research 2025年第7期20卷 1930-1943页

作者： Qinchao Hu Si Wang Weiqi zhang jing Qu Guang-Hui Liu State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijingChina Hospital of Stomatology Guanghua School of StomatologyGuangdong Provincial Key Laboratory of StomatologySun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Advanced Innovation Center for Human Brain Protection and National Clinical Research Center for Geriatric Disorders Xuanwu HospitalCapital Medical UniversityBeijingChina Aging Translational Medicine Center International Center for Aging and CancerBeijing Municipal Geriatric Medical Research CenterXuanwu HospitalCapital Medical UniversityBeijingChina CAS Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of Sciences and China National Center for BioinformationBeijingChina University of Chinese Academy of Sciences BeijingChina Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijingChina Aging Biomarker Consortium BeijingChina State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijingChina Beijing Institute for Stem Cell and Regenerative Medicine BeijingChina

The oral cavity is a complex physiological community encompassing a wide range of *** of oral microbiota can lead to various oral infectious diseases,such as periodontitis and tooth decay,and even affect systemic health,including brain aging and neurodegenerative *** studies have highlighted how oral microbes might be involved in brain aging and neurodegeneration,indicating potential avenues for intervention *** this review,we summarize clinical evidence demonstrating a link between oral microbes/oral infectious diseases and brain aging/neurodegenerative diseases,and dissect potential mechanisms by which oral microbes contribute to brain aging and *** also highlight advances in therapeutic development grounded in the realm of oral microbes,with the goal of advancing brain health and promoting healthy aging.

关键词： Alzheimer's disease brain aging multiple sclerosis neurodegeneration neurodegenerative diseases oral microbiota Parkinson's disease periodontitis bacteria Porphyromonas gingivalis