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Chinese Journal of Polymer Science 2016年第5期34卷 594-605页

作者： Li-nan Li cheng-dong xiong 陈栋梁 chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China University of Chinese Academy of Sciences Beijing 100049 China

In order to exploit the biological functions of materials, a series of new random terpolymers were synthesized by the ring-opening polymerization of p-dioxanone, trimethylene carbonate, and L-phenylalanine N-carboxyanhydride（L-PheNCA） in the presence of stannous octoate. The terpolymers were characterized by 1H-NMR, 13C-NMR, FTIR, and gel permeation chromatography. The effects of the reactant ratio, catalyst dosage, reaction temperature and time on the copolymerization were investigated, and were found to regulate the composition of the terpolymer. Increases in the reaction temperature, polymerization time, L-Phe-NCA monomer amount, and catalyst content generated a product with a slightly decreased molecular weight. The crystallinity of the terpolymer was investigated by differential scanning calorimetry and polarized optical microscopy. A reasonable mechanism for the polymerization was proposed based on the obtained results.

关键词： polymerization crystallinity calorimetry permeation monomer phenylalanine carbonate slightly dosage biodegradable

Synthesis of novel copolymer:Poly(p-dioxanone-co-L-phenylalanine)

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Chinese Chemical Letters 2013年第5期24卷 392-396页

作者： Bing Wang Chi Ma Zuo-Chun xiong cheng-dong xiong Quan-Hua Zhou dong-Liang Chen chengdu Institute of Organic Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Sichuan Staff University of Science and Technology

In order to expand the application of poly（p-dioxanone） or PPDO in biomedical area,a series of novel copolymers were synthesized successfully by one-step,melted copolymerization of p-dioxanone（PDO） and L-phenylalanine N-carboxyanhydride（L-Phe-NCA） *** the in-feed molar ratio of L-PheNCA /PDO equal to 1/20,the conversions of the two kinds of monomers were calculated from 1H NMR. The average molecular weight and polydispersity of the copolymer increase with the increasing reaction time and catalyst ***,the conversions of the two kinds of monomers did not change with the reaction conditions.A three-step mechanism is presented and proved by high resolution 1H NMR and IR spectrums.

关键词： Copolymer p-Dioxanone L-Phenylalanine Mechanism

Synthesis of novel biodegradable poly(ethylene glycol) analogue:Water-soluble aliphatic polyester with pendant oligo(ethylene glycol) chains

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Chinese Chemical Letters 2009年第12期20卷 1502-1505页

作者： Lei Feng Jian Yuan Hao cheng dong xiong Xian Mo Deng chengdu Institute of Organic Chemistry Chinese Academy of Sciences P.O. Box 415 Chengdu 610041 China School of Microeletronics and Solid State Electronics University of Electronic Science and Technology of China Chengdu 610054 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

A novel poly（ethylene glycol）（PEG） analogue composed of aliphatic polyester backbone and pendant oligo（ethylene glycol） short chains is reported. The PEG analogue is a copolymer synthesized by ring-opening alternating copolymerization of succinic anhydride with 2-（（2-（2-metho xyethoxy）ethoxy）methyl）oxirane. The structure of the copolymer was confirmed by ^1H NMR spectrum. The effects of the monomer feed ratio on the copolymerization were studied and the polymerization mechanism was given. The PEG analogue disclosed is water-soluble and expected to have promising applications in biomedical fields as a substitute of PEG due to the existence of degradable ester bond in the backbone.

关键词： Water-soluble PEG analogue 2-((2-(2-Methoxyethoxy)ethoxy)methyl)oxirane Ring-opening alternating copolymerization Polyester

Different crystallinity of poly(d,l-lactide-co-p-dioxanone) copolymers acquired by control of chain microstructure

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Chinese Chemical Letters 2009年第12期20卷 1506-1509页

作者： Hui Zhen Zhao Jian Yuan Hao cheng dong xiong Xian Mo Deng chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China School of Microeletronics and Solid State Electronics University of Electronic Science and Technology of China Chengdu 610054 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

Poly（d,l-lactide-co-p-dioxanone）（P（LA-co-PDO）） copolymers with different chain microstructures were synthesized by onestep or two-step bulk ring-opening polymerizations of d,l-lactide （LA） and p-dioxanone （PDO） monomers using stannous octoate [Sn（Oct）2]/n-dodecanol as the initiating system. The average sequence lengths of the lactidyl （LLA） and dioxanyl （LpDo） units were calculated from the ^1H NMR spectra. It was found that both LLA and Lpoo values from the two-step syntheses were significantly longer than those from the corresponding one-step syntheses, indicating more blocky structure achieved for the twostep copolymers. Corresponding to this difference in microstructure, the two-step copolymers were semi-crystalline, while the one-step copolymers were completely amorphous. In conclusion, the crystallinity of P（LA-co-PDO） copolymers could be adjusted conveniently to meet specific applications by changing the microstructure of the copolymers via different polymerization routes.

关键词： Poly(d,l-lactide-co-p-dioxanone) Copolymerization Chain microstructure Crystallinity

RING-OPENING COPOLYMERIZATION OF DL-LACTIDE AND POLY(ETHYLENE GLYCOL) INITIATED BY LANTHANUM ACETATE AND APPLICATION OF THE COPOLYMER AS MATRIX OF MICROSPHERES CONTAINING VIBRIO CHOLERA ANTIGENS

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Chinese Journal of Polymer Science 1999年第3期17卷 265-270页

作者： Xian-mo Deng Xiao-hong Li Ming-long Yuan xiong-wei Li cheng-dong xiong Zhi-tang Huang Wen-xiang Jia chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, chengdu, 610041, China Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100080, China West China University of Medical Sciences, chengdu, 610041, China Chinese Acad Sci Chengdu Inst Organ Chem Chengdu 610041 Peoples R China Chinese Acad Sci Inst Chem Beijing 100080 Peoples R China W China Univ Med Sci Chengdu 610041 Peoples R China

Poly-dl-lactide-poly(ethylene glycol) (PELA) triblock copolymers were synthesized with lanthanum acetate as the initiator. PELA microspheres with entrapped Vibrio Cholera antigen and outer membrane protein (OMP) were prepared by a double emulsion W/O/W based on solvent extraction methods. The obtained microspheres showed smooth and spherical surface and their size varied between 0.5 and 5.0 mu m, which are suitable for oral targeting delivery system. The distribution tests in rabbits and mice through scanning electronic micrography and fluorescence microscope indicated that microspheres have successfully reached the immunization-related tissues, such as the liver, spleen and intestinal peyer's patches, following oral administration. The PELA microspheres were also evaluated as an efficient antigen delivery system by enhancing a higher protective ratio against live Vibrios Cholera.

关键词： poly-dl-lactide-poly(ethylene glycol) Vibrio Cholera antigen lanthanum acetate microsphere protective ratio

MISCIBILITY AND CRYSTALLIZATION BEHAVIOR OF BIODEGRADABLE BLEND OF POLY(β—HYDROXYBUTYRATE)AND POLY(D,L—LACTIDE)—CO—POLY(ETHYLENE GLYCOL)

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Chinese Chemical Letters 1993年第3期4卷 265-268页

作者： Xian Mo DENG Lian Lai ZHANG cheng dong xiong chengdu Institute of Organic Chemistry,Academia Sinica,Chewgdu 610041

Studies on the miscibility of PHB/PELA blends showed that PHB and PELA were miscible in amorphous *** crystallization behavior of PHB in the blend was strongly de- pendent on the addition of PELA component.

关键词： PELA HYDROXYBUTYRATE)AND POLY LACTIDE MISCIBILITY AND CRYSTALLIZATION BEHAVIOR OF BIODEGRADABLE BLEND OF POLY PHB D,L CO

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基于指标多属性视角的工程项目评标模型

土木工程与管理学报 2017年第4期34卷 143-147页

作者：赵程伟董雄报洪青桂林电子科技大学商学院广西桂林541004

评标指标体系中的指标具有不同的属性,而现有评标方法忽略了其多属性的特点。为使评标决策更加科学合理,在分析指标体系中指标值数据类型的基础上,构建了指标值为精确数、区间数、三角模糊数等混合数据类型的TOPSIS法评标模型。结果表明... 详细信息

评标指标体系中的指标具有不同的属性,而现有评标方法忽略了其多属性的特点。为使评标决策更加科学合理,在分析指标体系中指标值数据类型的基础上,构建了指标值为精确数、区间数、三角模糊数等混合数据类型的TOPSIS法评标模型。结果表明:利用混合数据评标决策,兼顾了定性定量指标,其不仅有助于准确描述潜在投标人的综合实力,而且还有效的避免了不同数据类型指标值转换造成的信息损失或扭曲。最后通过示例分析及对比分析表明,该模型可行有效,易于接受和掌握,具有一定的实践和推广价值。

关键词：建设工程项目评标指标多属性混合TOPSIS法

基于Z-number折衷排序法的工程评标决策模型

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土木工程与管理学报 2017年第3期34卷 114-118页

作者：赵程伟董雄报洪青桂林电子科技大学商学院广西桂林541004

为减少评标过程中主观不确定性对评标结果的影响,提高评标的科学合理性。论文从评标实践的视角出发对评标决策方法的选取进行分析,将Z-number理论与折衷排序法引入到工程评标中,构建了基于Z-number理论的折衷排序法评标模型。Z-number... 详细信息

为减少评标过程中主观不确定性对评标结果的影响,提高评标的科学合理性。论文从评标实践的视角出发对评标决策方法的选取进行分析,将Z-number理论与折衷排序法引入到工程评标中,构建了基于Z-number理论的折衷排序法评标模型。Z-number模糊数综合考虑了评标过程中主观不确定性,能较好地解决定性指标量化问题,并减少主观不确定性对评标结果的影响。而折衷排序法以群体效应最大化和负面影响最小化的思想对投标人进行排序,所以其最佳折衷解更易于被决策者采纳。最后通过示例与对比分析结果表明,该模型简单可行,符合现行招标模式和评标专家的行为习惯,便于人们接受和掌握,因而具有较强的可操作性和实用价值。

关键词：建筑工程项目评标决策 Z-number理论折衷排序

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引流式双扣漏斗加速排盐并抑制返盐试验研究

干旱地区农业研究 2017年第1期35卷 283-288页

作者：校亮徐青衣华鹏董志成熊东红中国科学院山地灾害与地表过程重点实验室四川成都610041 中国科学院水利部成都山地灾害与环境研究所四川成都610041 中国科学院大学资源与环境学院北京100049 鲁东大学地理与规划学院山东烟台264000

为有效解决盐碱地植物根系因返盐受到胁迫以及重度退化盐碱地修复难题,利用盐碱土地"盐随水动"典型特点,从淋盐和抑盐角度开展盐碱化土壤的微域改良研究,设计了可快速淋盐的引流式双扣漏斗型防盐害保水的植物栽培系统。对不同处理措施(... 详细信息

为有效解决盐碱地植物根系因返盐受到胁迫以及重度退化盐碱地修复难题,利用盐碱土地"盐随水动"典型特点,从淋盐和抑盐角度开展盐碱化土壤的微域改良研究,设计了可快速淋盐的引流式双扣漏斗型防盐害保水的植物栽培系统。对不同处理措施(单形漏斗试验、双扣漏斗试验、引流式双扣漏斗试验、引流式双扣漏斗加壤内隔层试验)效果进行试验研究。结果表明:(1)采用引流式双扣漏斗加壤内隔层(处理4)降盐效果最为显著。0~20 cm土层处理4较对照组土壤含盐量自3.64%下降至0.66%,降低达5.53倍。(2)采用处理4,棉花发芽、成苗率显著提升,发芽率由对照组40.0%提升至86.0%;成苗率较对照组0%提升至82.0%。(3)不同处理措施下土壤含盐量及棉花种子发芽、成苗率对比发现,采用引流式双扣漏斗加壤内隔层可快速降低引流式双扣漏斗境内土壤盐分,显著提高棉花成苗率。研究表明,该系统可高效淋洗引流式双扣漏斗区土壤盐分,降低区内水分蒸发,阻隔区外水盐上行,防止区内土壤盐化,创造出保护根系、适宜植物生长的"小生境"。

关键词：引流式双扣漏斗壤内隔层盐分发芽率成苗率

聚(对氧环己酮-三亚甲基碳酸酯)静电纺膜的制备及其生物学与降解性能研究

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高分子学报 2017年第4期27卷 651-660页

作者：李丽楠刘永江刘书慧杨欢熊成东陈栋梁中国科学院成都有机化学研究所成都610041 中国科学院大学北京100049 青岛出入境检验检疫局青岛266001

通过静电纺丝技术,将二元共聚物聚(对氧环己酮-三亚甲基碳酸酯)(PDT)制成了膜材料,采用扫描电镜(SEM)观察了静电纺膜的形貌,当共聚物中TMC组分含量越高时,纤维丝之间黏结越严重.采用静态接触角仪测定了静电纺膜的接触角,表征了共聚物的... 详细信息

通过静电纺丝技术,将二元共聚物聚(对氧环己酮-三亚甲基碳酸酯)(PDT)制成了膜材料,采用扫描电镜(SEM)观察了静电纺膜的形貌,当共聚物中TMC组分含量越高时,纤维丝之间黏结越严重.采用静态接触角仪测定了静电纺膜的接触角,表征了共聚物的亲疏水性,PDT的亲水性介于PPDO与PTMC均聚物静电纺膜之间.对PDT共聚物静电纺膜进行了L929大鼠成纤维细胞培养实验,MTT和荧光染色结果说明PDT膜的细胞相容性良好.通过水解及酶解实验考察了材料的降解过程,PDT静电纺膜在脂肪酶存在下降解速率加快,材料的失重率、分子量损失、材料形貌破坏程度等均高于水解样品,这说明脂肪酶对含有TMC组分的聚合物的降解有促进作用.同时,降解过程中PBS溶液的p H值变化说明TMC组分的加入,减缓了降解过程中酸性物质的产生.

关键词：对氧环己酮三亚甲基碳酸酯静电纺膜降解