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Studies on Rheological, Thermal, and Mechanical Properties of Polylactide/Methyl Methacrylate-Butadiene-Styrene Copolymer/Poly(propylene carbonate) Polyurethane Ternary Blends

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Chinese Journal of Polymer Science 2019年第12期37卷 1273-1282,I0007页

作者： Ji-li Zhao Hong-Wei Pan hui-li yang Jun-Jia Bian hui-liang Zhang Ge Gao li-Song Dong College of Chemistry Jilin UniversityChangchun 130012China Department of Science Beihua UniversityJilin 132013China Key Laboratory of Polymer Ecomaterials Chinese Academy of SciencesChangchun Institute of Applied ChemistryChangchun 130022China Zhejiang Zhongke Applied Chemistry Technology Co. Ltd.Hangzhou 310000China

Polylactide(PLA),methyl methacrylate-butadiene-styrene copolymer(MBS),and poly(propylene carbonate)polyurethane(PPCU)were blended and subjected to blown film *** rheological,mechanical,morphological,thermal,and crystalline properties of the PLA/MBS/PPCU ternary blends and the mechanical properties of the resulting films were *** of mechanical test showed that PPCU and MBS could synergistically toughen *** impact strength of 50/10/40 PLA/MBS/PPCU blend(74.7 k J/m^2)was about 7.5 times higher than that of the neat PLA(10.8 k J/m^2),and the elongation at break of 50/10/40 PLA/MBS/PPCU blend(276.5%)was higher by about 45 times that of PLA(6.2%).The tear strength of PLA/MBS/PPCU films was 20 k N/m higher than that of PLA,and the elongation at break(MD/TD)of 50/10/40 PLA/MBS/PPCU films was 271.1%/222.3%,whereas that of PLA was only 2.7%/3.0%.POM observations displayed that the density of spherulite nucleation increased and the size of crystalline particles decreased with the addition of *** increasing PPCU content from 5%to 20%,the density of spherulite nucleation increased and the size of crystalline particles decreased continuously,but the nucleation density of spherulites was slightly lowered with increasing PPCU content from 30%to 40%.The PLA/MBS/PPCU films exhibited excellent mechanical properties,which expanded the application range of these biodegradable films.

关键词： Biodegradable Polylactide Poly(propylene carbonate)polyurethane Methyl methacrylate-butadiene-styrene copolymer Films

Entropy of Dirac Field in Non-stationary and Slowly Changing Reissner-Nordstrom Black Hole

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Communications in Theoretical Physics 2005年第5X期44卷 955-960页

作者： li hui-ling yang Shu-Zheng JIANG Qing-Quan Institute of Theoretical Physics China West Normal University Nanchong 637002 China

Using the thin film brick-wall model and WKB approximation, the entropy of the Dirac field in the non-stationary and slowly changing Reissner-Nordstrom (R-N) black hole is calculated. The result shows that the entropy... 详细信息

关键词： slowly changing thin brick-wall model Dirac field entropy of black hole

Cardioprotective effect of liposomal prostaglandin E1 on a porcine model of myocardial infarction reperfusion no-reflow

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第8期12卷 638-643页

作者： Jia-hui li Peng yang Ai-li li Yong WANG Yuan-nan KE Xian-lun li Department of Cardiology China-Japan Friendship Hospital Beijing 100029 China

Objective： To evaluate whether liposomal prostaglandin E1 （lipo-PGE1） can decrease reperfusion no-reflow in a catheter-based porcine model of acute myocardial infarction （AMI）. Methods： Twenty-two male Chinese mini-swines were randomized into three groups： six in a sham-operation group, and eight each in the control and lipo-PGE1 groups. The distal part of the left anterior descending coronary artery （LAD） in the latter two groups was completely occluded for 2 h, and then reperfused for 3 h. lipo-PGE1 （1 pg/kg） was injected 10 min before LAD occlusion until reperfusion for 1 h in the lipo-PGE1 group. Hemodynamic data and proinflammatory cytokines were examined before AMI, 2 h after occlusion, and 1, 2, and 3 h after reperfusion. Myocardial contrast echocardiography （MCE） and double staining were performed to evaluate the myocardial no-reflow area （NRA）. Results： Left ventricular systolic pressure and end-diastolic pressure significantly improved in the lipo-PGE1 group after reperfusion compared with the control group and also 2 h after AMI （P〈0.05 for both）. MCE and double staining both showed that lipo-PGE1 decreased reperfusion NRA after AMI （P〈0.05, P〈0.01）. lipo-PGE1 decreased serum interleukin-6 （IL-6） and tumor necrosis factor-a （TNF-a） after myocardial infarction reperfusion （P〈0.05 for both）. Conclusions： lipo-PGE1 is cardioprotective in our porcine model of myocardial infarction reperfusion no-reflow, decreasing NRA and attenuating the inflammatory response.

关键词： liposomal prostaglandin E1 (lipo-PGE1) Reperfusion no-reflow Myocardial infarction

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

Experimental and theoretical analysis on the procedure for estimating geo-stresses by the Kaiser effect

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International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 514-518页

作者： Yuan-hui li Yu-jiang yang Jian-po liu Xing-dong Zhao College of Resources and Civil Engineering Northeastern University Shenyang 110004 China

Acoustic emission tests of the core specimens retrieved from boreholes at the depth over 1000 m in Hongtoushan Copper Mine were carried out under uniaxial compressive loading, and the numerical test was also done by using the rock failure process analysis （RFPA2D） code, based on the procedure for estimating geo-stresses by the Kaiser effect under uniaxial compression. According to the statistical damage mechanics theory, the Kaiser effect mechanism was analyzed. Based on these analyses, it is indicted that the traditional method of estimating geo-stresses by the Kaiser effect is not appropriate, and the result is usually smaller than the real one. Furthermore, the greater confining compression in the rock mass may result in a larger difference between the Kaiser effect stresses acquired from uniaxial loading in laboratory and the real in-situ stresses.

关键词： rock stresses Kaiser effect cyclic loading acoustic emission

Rheological, Thermal and Mechanical Properties of Biodegradable Poly(propylene carbonate)/Polylactide/Poly(1,2-propylene glycol adipate) Blown Films

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Chinese Journal of Polymer Science 2015年第12期33卷 1702-1712页

作者： Yan-ping Hao hui-li yang Gui-bao Zhang 张会良 Ge Gao li-song Dong College of Chemistry Jilin University Key Laboratory of Polymer Ecomaterials Chinese Academy of Sciences Changchun Institute of Applied Chemistry

Poly（propylene carbonate）（PPC） was blended with polylactide （PLA） and poly（1,2-propylene glycol adipate）（PPA） using a twin screw extruder. Then the PPC/PLA/PPA films were prepared using the blown film technique. DMA results showed that PPA could act as a plasticizer and improve the miscibility between PPC and PLA. Crystal morphology displayed that blending PLA with the amorphous PPC led to a decrease of the spherulite size of PLA. The results of mechanical tests indicated that PPC-rich films showed high elongation at break and PLA-rich films showed high tear strength and good optical properties. The content of PPC and PLA significantly affected the physical properties of the films. With increasing PPC content, the melt strengths of the PPC/PLA/PPA films were enhanced. These findings contributed to the biodegradable materials application for designing and manufacturing polymer packaging.

关键词： Poly(propylene carbonate) Polylactide Plasticizer Blown films.

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

Study on the Relationship between Plasma very Low Density lipoprotein Concentration and Egg Composition Traits in Layer Type Chickens

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Journal of Northeast Agricultural University(English Edition) 1997年第1期4卷 45-51页

作者： li hui, yang Shan (Northeast Agricultural University, Harbin, 150030, PRC)

The chickens used in this study were from a pure line of brown shell egg-type (YAFA) female grandparents of 17-week-old. Plasma very low density lipoprotein (VLDL) concentration was measured with turbidimetric assay. The experimental results showed that there was a close relationship between plasma VLDL concentration and egg composition traits, and a positive phenotypic correlation trend was found between 29-week plasma VLDL concentration and 44-week yolk weight, and the genetic correlation coefficient was 0.234. Both the phenotypic and genetic correlations between 29-week plasma VLDL concentration and albumen weight were negative. Significant positive phenotypie correlations were, however, observed between yolk ratio, or the yolk/albumen ratio and 29-week plasma VLDL concentration, and their genetic correlation coefficients were 0.250 and 0.223, respectively.

关键词： Egg-type chickens plasma VLDL concentration egg composition

Synthesis and nonlinear optical properties of copolymers of fluoro-containing bisphenol A and chromophores

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Chinese Chemical Letters 2011年第11期22卷 1367-1370页

作者： Jie Ping Shi hui yang li Wei Hong Wen Hu Guo Yuan Lu Department of Chemistry State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 210093 China

A series of new fluoro-containing copolymers have been synthesized by a Mitsunobu reaction with 4,4＇-（hexafluoroisopropylidene） bisphenol A（6FBPA） and the corresponding N,N-dihydroxyethylaminoaryl azo or ring-locked triene compounds, which have high thermal stability and good solubility in organic *** nonlinear optical（NLO） measurements made by Marker fringe method at 1064 nm indicate that the copolymers embedded with the ring-locked triene and azo chromophores exhibit higher macroscopic nonlinear optical coefficient（70.2 pm/V and 26.5-34.6 pm/V,respectively）.Thermal analysis and UV-visible absorption spectra show that the copolymers have good thermal stability（T_d= 264-319℃） and optical transparency （λ_（max）500 nm）.

关键词： NLO materials NLO chromophores Ring-locked triene Mitsunobu reaction