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Journal of Materials Science & Technology 2009年第6期25卷 749-752页

作者： Gang Du Jingwei Deng Desheng Yan Mingjiu zhao lijian Rong Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Effects of intermediate annealing temperature and time after hot working on recrystallization temperature （Tr） of Al-Mg-Sc-Zr alloy subjected to further cold working were investigated. It was found that Tr of cold worked alloy dropped with the rise of intermediate annealing temperature or extension of annealing time, clue to coarsening of Al3（Sc, Zr） particles during intermediate annealing. After annealed at 550℃ for 1 h or 475℃ for 50 h, Tr is nearly same as that in a Sc, Zr free 5A06 alloy. Coarsening mechanism was also discussed. After hot rolling, residual dislocations promoted diffusion of Sc and Zr atoms at the elevated temperature of the intermediate annealing. Easier diffusion sped the growth of the AI3（Sc, Zr） particles, resulting in a coherency loss and quantity reduction of the particles.

关键词： Al3(Sc, Zr) precipitates Coarsening Recrystallization Diffusion

Studies of poly-L-lysine-starch nanoparticle preparation and its application as gene carrier

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Science China Chemistry 2005年第2期48卷 162-166页

作者： XIAO Suyao LIU Xuanming TONG Chunyi LIU Jun TANG Dongying zhao lijian Institute of Life Science and Biotechnology College of Chemistry & Chemical Engineering Hunan University Changsha 410082 China Institute of Life Science and Biotechnology College of Chemistry & Chemical Engineering Hunan University Changsha 410082 China Institute of Life Science and Biotechnology College of Chemistry & Chemical Engineering Hunan University Changsha 410082 China Institute of Life Science and Biotechnology College of Chemistry & Chemical Engineering Hunan University Changsha 410082 China Institute of Life Science and Biotechnology College of Chemistry & Chemical Engineering Hunan University Changsha 410082 China Institute of Life Science and Biotechnology College of Chemistry & Chemical Engineering Hunan University Changsha 410082 China

Anion starch nanoparticle (StNP) with a diameter of 50 nm was prepared in wa- ter-in-oil microemulsion, with soluble starch as raw materials and POCl3 as crosslinking agent. PLL-StNP was prepared by linking poly-L-lysine (PLL) on the surface of StNP. At the same time, the size of PLL-StNP and its stability in aqueous solution were checked by AFM. The analysis of plasmid DNA binding, DNase I enzymatic degradation, toxicity and transfection were done. We discovered that PLL-StNP may be used as non-virus nanoparticle gene carrier. And we devel- oped the method of preparing PLL-StNP gene carrier and used it in cell transfection. As non-virus gene carrier, PLL-StNP has some advantages, such as large load of DNA, high transfection effi- ciency, low cell toxicity and biodegradability.

关键词： anion starch nanoparticle, poly-L-lysine, non-virus gene carrier, cell transfection.

An Aptamer-based Colorimetric Sensor for Streptomycin and Its Application in Food Inspection

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Chemical Research in Chinese Universities 2017年第5期33卷 714-720页

作者： LIU Zhongcheng ZHANG Yanfen XIE Yao SUN Ying BI Kewei CUI Zhe zhao lijian FAN Wufang College of Life Sciences Hebei University Baoding 071002 P. R. China Key Laboratory of Pharmaceutical Quality Control of Hebei Province Baoding 071002 P. R. China Office of Science and Technology Hebei University Baoding 071002 P. R. China

An aptamer-based colorimetric biosensor was developed, which could be used to detect residual strepto- mycin from food quickly and cost-effectively. The ssDNA aptamer target for streptomycin was obtained using sys- temic evolution of ligands by exponential enrichment through affinity chromatography. A total of 19 candidates were obtained after 10 rounds of selection and were grouped into 3 families according to their similarity of sequence and structure. Among them, aptamer A15 showed the highest affinity for streptomycin tested by fluorescence intensity analysis with a dissociation constant of 6.07 nmol/L. Aptamer A15 also exhibited a higher streptomycin specificity with the lowest detectable limit of 25 nmol/L according to the value of A620/A520 ratio with AuNP-based colorimetric assay. The method was specific and sensitive for the detection of streptomycin from simply-treated milk and honey at 100 and 125 nmol/L, respectively, and is a promising approach to monitor antibiotics or other small molecules ana- logues in food inspection.

关键词： Aptamer Streptomycin Systematic evolution of ligands by exponential enrichment(SELEX) Au nanopar- ticle Aptasensor

Preparation of folate-conjugated starch nanoparticles and its application to tumor-targeted drug delivery vector

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Chinese Science Bulletin 2006年第14期51卷 1693-1697页

作者： XlAO Suyao TONG Chunyi LIU Xuanming YU Danmi LIU Qiaoling XUE Changgang TANG Dongyin zhao lijian State Key Laboratory of Chemo/Biosensing and Chemometrics LifeScience and Technology Institute Hunan University Changsha 410082China

Anion starch nanoparticles (StNP) were prepared in water-in-oil microemulsion. Folate modi-fied with PEG was conjugated to the surface of StNP to obtain the folate-conjugated starch nanoparticles (FA-PEG/StNP). The average diameter of FA-PEG/ StNP determined by AFM and Zeta-Sizer apparatus was about 130 nm. Doxorubicin (DOX)-loaded FA- PEG/StNP was obtained via infiltrating combination. The result of UV spectrophotometer showed that the saturation concentration of DOX-loaded FA-PEG/ StNP was 28 μg/mg, which was effective for the con-trolled release of anticancer drug DOX. The cell ex-periments showed that the Lc50 of DOX-loaded FA-PEG/StNP and DOX-loaded StNP was higher than that of DOX, which indicates that FA-PEG/StNP and StNP can decrease the toxicity of DOX; while the lethal rate of DOX-loaded FA-PEG/StNP was 3 times that of DOX-loaded StNP with the same quantity of DOX, which indicates that FA in FA-PEG/StNP is ef-fective for improving the targeting function of nanoparticles, thus enhancing the inhibition effect of anticancer drug to cancer cell. This work demon-strates that the FA-PEG/StNP system is a potentially useful system for the targeted delivery of anticancer drug DOX.

关键词：叶酸受体肿瘤细胞药物输送阴离子淀粉乳酸 FA-PEG/ StNP

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网络环境下的新闻资料工作

图书馆 2007年第4期 134-135,139页

作者：赵李坚湖南日报社新闻研究部湖南长沙410005

在现代信息环境下,新闻资料的收集、存储、查询等均对传统的新闻资料工作产生巨大影响。新闻资料工作必须面对信息时代的挑战,转变观念,推陈出新,求得创新发展。

关键词：信息时代新闻资料工作创新服务

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论现代信息服务业的个性化追求

图书馆 2006年第4期 76-77,91页

作者：赵李坚湖南日报新闻研究部湖南长沙410005

现代信息服务业需要满足社会个性化的需求。实施个性化信息服务,要坚持人性化和科学化的紧密结合;要以用户的需求为中心,以用户满意为目标。

关键词：信息服务业个性化追求原则服务形式

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大型互联网平台扼杀式并购规制的完善与变革

科技和产业 2024年第1期24卷 144-150页

作者：赵力践西安财经大学法学院西安710100

互联网平台发展壮大的同时垄断问题也引起全世界反垄断执法机构的关注。尽管《反垄断法》的修订回应了公众对数字领域垄断问题的部分关切,但传统事先申报标准无法满足互联网平台反垄断执法需求,且实质性审查制度在新业态下陷入失灵,大... 详细信息

互联网平台发展壮大的同时垄断问题也引起全世界反垄断执法机构的关注。尽管《反垄断法》的修订回应了公众对数字领域垄断问题的部分关切,但传统事先申报标准无法满足互联网平台反垄断执法需求,且实质性审查制度在新业态下陷入失灵,大量大型平台企业并购初创企业案件长期逃脱反垄断审查。为此,可以通过修正申报标准、完善相关市场界定、重塑反竞争评估、优先适用行为性限制条件以及构建长效监管机制来规制扼杀式并购行为。

关键词：大型互联网平台扼杀式并购经营者集中反垄断规制