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Thermal,Rheological and Mechanical Properties of Biodegradable Poly(propylene carbonate)/Epoxidized Soybean Oil Blends

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Chinese Journal of Polymer Science 2021年第12期39卷 1572-1580页

作者： ling Zhao shi-ling jia Ze-Peng Wang Yun-Jing Chen Jun-jia Bian Li-Jing Han Hui-Liang Zhang Li-Song Dong Changchun UniversityofTechnology Changchun 130012China Key Laboratory of Polymer Ecomaterials Chinese Academy of SciencesChangchun Institute of Applied ChemistryChangchun 130022China Sinopec-SK(Wuhan)Petrochemical Company Limited Wuhan 430000China

Biodegradable poly(propylene carbonate)(PPC)/epoxidized soybean oil(ESO)blends with different component ratios were prepared by melt blending to improve the performance of *** phase morphology,thermal properties,rheological properties and mechanical properties of the blends were in vestigated in *** exami nation revealed good in terfacial adhesi on betwee n PPC matrix and *** to DSC and DMA,as the content of ESO increased,the glass transition temperature of the PPC component increased,indicating that there was a strong in terfacial in teracti on between the PPC matrix and *** in terfacial in teraction may be caused by rin g-opening reaction between the hydroxyl end groups of PPC and the epoxy groups of ESO,which restricted the chain movement of PPC *** disappearanee of the epoxy groups in FTIR indicated that the in terfacial in teracti on betwee n the two phases was due to the rin g-openi ng reactio n betwee n PPC and *** the addition of ESO,the thermal stabilities were *** the increasing ESO content,the modulus gradually ***,the stre ngth at yield,the strength at break and the elon gation at break were in creased for the PPC/ESO blends,suggest!ng that the enhancement of the strength and toughness of PPC was achieved by the incorporation of *** rheological measurement revealed that the complex viscosity,storage modulus and loss modulus of PPC were in creased with the increasi ng ESO content at low freque ncy,which indicated that the addition of ESO enhanced the melt strength of PPC in stead of plasticizi ng PPC.

关键词： Poly(propylene carbonate) Epoxy soybean oil Compatibility Mechanical properties

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Biodegradable Poly(butylene adipate-co-terephthalate)/Poly(glycolic acid) Films: Effect of Poly(glycolic acid) Crystal on Mechanical and Barrier Properties

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Chinese Journal of Polymer Science 2023年第7期41卷 1123-1132页

作者： Hong-Wei Pan Ye Wang shi-ling jia Yan Zhao Jun-jia Bian Hui-Li Yang Yan-Ping Hao Li-Jing Han Hui-Liang Zhang Key Laboratory of Polymer Ecomaterials Chinese Academy of SciencesChangchun Institute of Applied ChemistryChangchun130022China School of Pharmaceutical Sciences Changchun University of Chinese MedicineChangchun130117China Changchun University of Technology Changchun130012China Shandong Dawn Polymer Co. Ltd.Longkou265700China

Binary biodegradable polymers films, poly(butylene adipate-co-terephthalate)(PBAT) and poly(glycolic acid)(PGA), were prepared through batch melt mixing to obtain Film Ⅰ and Film Ⅱ under two different processing conditions. PGA crystals played a major role in enhancing the mechanical and barrier properties of the films. For Film Ⅰ, there were initial PGA crystals before the film blowing process, the PGA molecular chain further crystallized, forming the oriented crystallization of PGA. Moreover, the Xcand crystalline size in Film Ⅰ were higher than those in Film Ⅱ. Compared with the different processing methods, Film Ⅰ has excellent mechanical and oxygen barrier properties due to the crystallization and orientation. The tensile strength reached 45.0 MPa, and tear strength exceeded 138.2 kN/m, while the elongation at break was as high as 750% for PBAT/PGA 85/15 in Film Ⅰ. The WVTR, WVP coefficients, and OP coefficients of PBAT/PGA films were decreased obviously with increasing the PGA content both in Film Ⅰ and Film Ⅱ. Moreover, the barrier properties of oxygen in Film Ⅰ were better than that in Film Ⅱ. This work reveals a feasible processing technique by introducing of initial crystallization of PGA to blow PBAT/PGA films with excellent mechanical and barrier properties.

关键词： Poly(butylene adipate-co-terephthalate) Poly(glycolic acid)(PGA) Biodegradable polymers Films

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Biodegradable Foaming Material of Poly(butylene adipate-co-terephthalate)(PBAT)/Poly(propylene carbonate)(PPC)

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Chinese Journal of Polymer Science 2022年第2期40卷 208-219页

作者： Han-Lin Tian Ze-Peng Wang shi-ling jia Hong-Wei Pan Li-Jing Han Jun-jia Bian Ying Li Hui-Li Yang Hui-Liang Zhang Changchun University of Technology School of Chemical EngineeringChangchun 130012China Key Laboratory of Polymer Ecomaterials Chinese Academy of SciencesChangchun Institute of Applied ChemistryChangchun 130022China Jilin COFCO Biochemistry Packaging Co. Ltd.Liaoyuan 136300China

A biodegradable blend foaming material of poly(butylene adipate-co-terephthalate)(PBAT)/poly(propylene carbonate)(PPC)was successfully prepared by chemical foaming agent and screw extrusion ***,PBAT was modified by bis(tert-butyl dioxy isopropyl)benzene(BIBP)for chain extension,and then the extended PBAT(E-PBAT)was foamed with PPC using a twin(single)screw *** analyzing the properties of the blends,we found that Young’s modulus increased from 58.8 MPa of E-PBAT to 244.7 MPa of E-PBAT/PPC 50/*** viscosity of the polymer has a critical influence on the formation of *** with neat PBAT(N-PBAT),the viscosity of E-PBAT increased by 3396 Pa·s and E-PBAT/PPC 50/50 increased by 8836 Pa·***,the dynamic mechanical analysis(DMA)results showed that the storage modulus(E’)at room temperature increased from 538 MPa to 1650 *** various phase morphologies(“sea-island”,“quasi-co-continuous”and“cocontinuous”)and crystallinity of the blends affected the spread velocity of gas and further affected the foaming morphology in E-PBAT/PPC ***,through the analysis of phase morphology and foaming mechanism,we concluded that the E-PBAT/PPC 70/30 component has both excellent strength and the best foaming performance.

关键词： Poly(butylene adipate-co-terephthalate) Poly(propylene carbonate) Phase structure Biodegradable foam Extrusion foaming

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Mechanical Properties, Crystallization and Biodegradation Behavior of the Polylactide/Poly(3-hydroxybutyrate-co-4-hydroxybutyrate)/ Poly(butylene adipate-co-terephthalate) Blown Films

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Chinese Journal of Polymer Science 2020年第10期38卷 1072-1081,I0005页

作者： Xiang-Yu Wang Hong-Wei Pan shi-ling jia Zeng-Wen Cao Li-Jing Han Hui-Liang Zhang Li-Song Dong Key Laboratory ofPolymer Ecomaterials Chinese Acadermy of SciencesChangchun Istitute of Applied ChemistryChangchun 130022 China University of Science and Technology of China Hefei 230026 China Zhejiang Zhongke Applied Chemistry Technology Co LtdHangzhou 30000 China

Polactide(PLA),poly(3-hydroxybutyrate-co-4-hydroxybutyrate)(P(3HB-CO-4HB)),and poly(butylene adipate co-terephthalate)(PBAT)ternary blends were prepared by extrusion *** biodegradable PLA/P(3HB-co 4HB)/PBAT films were successfully obtained by using blown films *** siffness-toughness balance was achieved for 55/10/35 PLA/P(3HB-co 4HB)/PBAT *** tensile strength reached 33.0 MPa(MD)and 23.5 MPa(TD).the elongation at break exceeded 1309%,and tear strength exceeded 110 kN/*** Young's modulus as low as about 1800 MPa also met packaging *** observations revealed rough and long ligaments,indicating that the tear specimens were broken *** addition of PBAT elastomers was the main reason for the improved toughness of the *** DMA and SEM analysis,it was demonstrated that PLA P(3HB co 4HB),and PBAT were prilly *** increasing P(3HB CO-4HB)content,the melt and cold crstallization of PLA was *** enzymatic degradation experiments indicated that the films had good *** findings gave important implications for designing and manufacturing biodegradation package of high biological carbon content.

关键词： Polylactide Poly(3 hydroxybutyrate co4-hydrxybutyrate) Blown flms Mechanical properties Biodegradability

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Superior Toughened Biodegradable Poly(L-lactic acid)-based Blends with Enhanced Melt Strength and Excellent Low-temperature Toughness via In situ Reaction Compatibilization

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Chinese Journal of Polymer Science 2023年第3期41卷 373-385,I0007页

作者： shi-ling jia Xiang-Yu Wang Ye Zhang Xiang-Yu Yan Hong-Wei Pan Yan Zhao Li-Jing Han Hui-Liang Zhang Li-Song Dong Hui-Xuan Zhang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Materials Science and Engineering Changchun University of TechnologyChangchun 130012China

The toughened poly(L-lactic acid)/poly(butylene succinate-butylene terephthalate)(PLLA/PBST) blend with enhanced melt strength and excellent low temperature toughness and strength was prepared by melt compounding through in situ compatibilization reaction in presence of multifunctional epoxy compound(ADR).The PLLA/PBST blend was an immiscible system,and the compatibility of the PLLA/PBST blend was improved after adding *** and GPC curves confirmed the formation of the PLLA-g-PBST copolymer,which improved the interfacial bonding of the blend and therefore the PLLA/PBST/ADR blend showed excellent melt strength and mechanical *** the PLLA/PBST/ADR blend with 70/30 PLLA/PBST content,the complex viscosity increased significantly with increasing ADR ***,the tensile strength,elongation at break and impact strength all increased obviously with increasing the ADR *** elongation at break of the blend reached the maximum value of 392.7%,which was 93.2 times that of neat *** the impact strength of the blend reached the maximum value of 74.7 k J/m~2,which was 21.3 times that of neat ***,the PLLA/PBST/ADR blend exhibited excellent lowtemperature toughness and *** –20 ℃,the elongation at break of the PLLA/PBST/ADR blend was as high as 93.2%,and the impact strength reached 18.8 k J/m~***,the tensile strength of the blend at low temperature was also high(64.7 MPa),which was beneficial to the application of PLA in the low temperature *** addition,the PLLA/PBST/ADR blend maintaind good biodegradability,which was of great significance to the wide application of PLLA.

关键词： Poly(L-lactic acid) PBST Compatibilization Super toughness Low-temperature mechanical properties Biodegradability

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数据挖掘在数字图书馆个性化服务中的应用

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农业网络信息 2009年第4期 77-79页

作者：史嘉陵重庆图书馆重庆400037

个性化服务是整个数字图书馆服务系统中十分关键的部分。本文从数字图书馆个性化服务、数据挖掘的特点入手,描述了数据挖掘技术和方法,着重探讨了数据挖掘技术在数字图书馆个性化服务中的应用。

关键词：数字图书馆个性化服务数据挖掘 Web挖掘文本挖掘

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提高学生应用写作技能的几种教学方法

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长江工程职业技术学院学报 2001年第3期18卷 46-47页

作者：时佳玲广东电力工业学校广东广州510630

应用文写作过去常规教学方式是:定义+作用+分类+格式+要求+举例.这种方法偏重知识的传授,忽视了学生写作能力的培养.学生看看就懂,考试时填填空,解释一下名词,回答一下问题就算过关;而写作时,却眼高手低,更不要说走上社会能适应工作需要了.

关键词：应用文写作教学应用写作技能文艺语体艺术语体文种教学方法

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miRNA-21-5p is an important contributor to the promotion of injured peripheral nerve regeneration using hypoxia-pretreated bone marrow-derived neural crest cells

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Neural Regeneration Research 2025年第1期20卷 277-290页

作者： Meng Cong Jing-Jing Hu Yan Yu Xiao-Li Li Xiao-Ting Sun Li-Ting Wang Xia Wu ling-Jie Zhu Xiao-jia Yang Qian-Ru He Fei Ding Hai-Yan shi School of Medicine Nantong UniversityNantongJiangsu ProvinceChina Key Laboratory of Neuroregeneration of jiangsu and Ministry of Education and Coinnovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Department of Physiology Jiangsu Health Vocational CollegeNanjingJiangsu ProvinceChina Department of Pathology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina

Our previous study found that rat bone marrow–derived neural crest cells(acting as Schwann cell progenitors)have the potential to promote long-distance nerve ***-based therapy can enhance peripheral nerve repair and regeneration through paracrine bioactive factors and intercellular ***,the complex contributions of various types of soluble cytokines and extracellular vesicle cargos to the secretome remain *** investigate the role of the secretome and extracellular vesicles in repairing damaged peripheral nerves,we collected conditioned culture medium from hypoxia-pretreated neural crest cells,and found that it significantly promoted the repair of sensory neurons damaged by oxygen-glucose *** mRNA expression of trophic factors was highly expressed in hypoxia-pretreated neural crest *** performed RNA sequencing and bioinformatics analysis and found that miR-21-5p was enriched in hypoxia-pretreated extracellular vesicles of neural crest ***,to further clarify the role of hypoxia-pretreated neural crest cell extracellular vesicles rich in miR-21-5p in axonal growth and regeneration of sensory neurons,we used a microfluidic axonal dissociation model of sensory neurons in vitro,and found that hypoxia-pretreated neural crest cell extracellular vesicles promoted axonal growth and regeneration of sensory neurons,which was greatly dependent on loaded ***,we constructed a miR-21-5p-loaded neural conduit to repair the sciatic nerve defect in rats and found that the motor and sensory functions of injured rat hind limb,as well as muscle tissue morphology of the hind limbs,were obviously *** findings suggest that hypoxia-pretreated neural crest extracellular vesicles are natural nanoparticles rich in ***-21-5p is one of the main contributors to promoting nerve regeneration by the neural crest cell *** helps to explain the mechanism of action of the secretome and e

关键词： axotomy cell-free therapy conditioned medium extracellular vesicles hypoxic preconditioning microRNA oxygen-glucose deprivation peripheral nerve injury Schwann cell precursors

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Understanding the local structure and thermophysical behavior of Mg-La liquid alloys via machine learning potential

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 439-449页

作者： jia Zhao Taixi Feng Guimin Lu National Engineering Research Center for Integrated Utilization of Salt Lake Resource East China University of Science and TechnologyShanghai 200237China Joint International Laboratory for Potassium and Lithium Strategic Resources East China University of Science and TechnologyShanghai 200237China

The local structure and thermophysical behavior of Mg-La liquid alloys were in-depth understood using deep potential molecular dynamic(DPMD) simulation driven via machine learning to promote the development of Mg-La alloys. The robustness of the trained deep potential(DP) model was thoroughly evaluated through several aspects, including root-mean-square errors(RMSEs), energy and force data, and structural information comparison results;the results indicate the carefully trained DP model is reliable. The component and temperature dependence of the local structure in the Mg-La liquid alloy was analyzed. The effect of Mg content in the system on the first coordination shell of the atomic pairs is the same as that of temperature. The pre-peak demonstrated in the structure factor indicates the presence of a medium-range ordered structure in the Mg-La liquid alloy, which is particularly pronounced in the 80at% Mg system and disappears at elevated temperatures. The density, self-diffusion coefficient, and shear viscosity for the Mg-La liquid alloy were predicted via DPMD simulation, the evolution patterns with Mg content and temperature were subsequently discussed, and a database was established accordingly. Finally, the mixing enthalpy and elemental activity of the Mg-La liquid alloy at 1200 K were reliably evaluated,which provides new guidance for related studies.

关键词： magnesium-lanthanum liquid alloys local structure macroscopic properties thermodynamic behavior deep potential mo-lecular dynamic simulation

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百笑灸治疗原发性痛经疗效观察

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上海针灸杂志 2019年第11期38卷 1243-1247页

作者：施凌佳张健铖绍兴市柯桥区中医医院绍兴312030 江苏省涟水县人民医院淮安223400

目的观察百笑灸治疗原发性痛经的临床疗效。方法 202例原发性痛经患者随机分为A组67例、B组70例和C组65例。A组患者用百笑灸治疗,灸治时间30 min;B组患者用百笑灸治疗,灸治时间15 min;C组采用布洛芬缓释胶囊治疗。观察3组不同时间视觉... 详细信息

目的观察百笑灸治疗原发性痛经的临床疗效。方法 202例原发性痛经患者随机分为A组67例、B组70例和C组65例。A组患者用百笑灸治疗,灸治时间30 min;B组患者用百笑灸治疗,灸治时间15 min;C组采用布洛芬缓释胶囊治疗。观察3组不同时间视觉模拟量表(VAS)评分、治疗前后子宫动脉血流动力学指标和前列腺素F2α(PGF2α)水平,并比较3组即时疗效、近期疗效及远期疗效。结果 A组、B组及C组即时疗效总有效率分别为94.0%、82.9%、67.7%,差异有统计学意义(P<0.05);A组、B组及C组近期疗效总有效率分别为97.0%、87.1%、72.3%,差异有统计学意义(P<0.05);A组、B组及C组远期疗效总有效率分别为95.5%、84.3%、66.2%,差异有统计学意义(P<0.05)。3组治疗后VAS评分、动脉阻力指数(RI)、搏动指数(PI)、PGF2α水平均降低(P<0.05),A组低于B组及C组(P<0.05)。3组治疗后收缩期峰值流速(PSV)、舒张末期流速(EDV)均升高,A组高于B组及C组(P<0.05)。结论百笑灸治疗原发性痛经疗效显著,明显减轻患者疼痛及子宫血液循环,且灸治时间30 min效果优于灸治15 min。

关键词：灸法百笑灸痛经视觉模拟量表前列腺素F2α

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