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Experimental and Data Fitting Guidelines for the Determination of Polymer Crystallization Kinetics

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Chinese Journal of Polymer Science 2022年第6期40卷 658-691页

作者： Ricardo Arpad Perez-Camargo guo-ming liu Du-Jin Wang Alejandro J.Muller Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Engineering PlasticsInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China POLYMAT and Department of Polymers and Advanced Materials:Physics Chemistry and TechnologyFaculty of ChemistryUniversity of the Basque Country UPV/EHUDonostia-San Sebastián 20018Spain IKERBASQUE Basque Foundation for ScienceBilbao 48013Spain

The crystallization kinetics of semicrystalline polymers is often studied with isothermal experiments and analyzed by fitting the data with analytical expressions of the Avrami and Lauritzen and Hoffman(LH)*** correctly carry out the analysis,precautions in both experiments and data fitting should be ***,we systematically discussed the factors that influence the validity of the crystallization kinetics *** basic concepts and fundamentals of the Avrami and LH theories were introduced at ***,experimental protocols were discussed in *** clarify the impact of various experimental parameters,selected common polymers,i.e.,polypropylene and polylactide,were studied using various experimental techniques(i.e.,differential scanning calorimetry and polarized light optical microscopy).Common mistakes were simulated under conditions when non-ideal experimental parameters were ***,from a practical point of view,we show how to fit the experimental data to the Avrami and the LH theories,using an Origin■App developed by us.

关键词： Isothermal crystallization Avrami equation Lauritzen and Hoffman theory Thermal analysis Step-crystallization

Stress-induced Solid-Solid Crystal Transition in Trans-1,4-polyisoprene

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Chinese Journal of Polymer Science 2022年第3期40卷 256-265,I0006页

作者： Chun-Bo Zhang Lei Wang Bo Yang Hui Zhao guo-ming liu Du-Jin Wang Shenzhen Key Laboratory of Polymer Science and Technology College of Materials Science and EngineeringShenzhen UniversityShenzhen 518060China CAS Key Laboratory of Engineering Plastics Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China School of Materials Science&Engineering Beijing Institute of Fashion TechnologyBeijing 100029China

The polymorphic transition of trans-1,4-polyisoprene(TPI) during stretching was investigated by in situ wide-angle X-ray diffraction and Fourier transform infrared spectroscopy. The influences of the initial structure, stretching temperature, and strain rate on the contents of different crystal modifications(α, β) were explored. The results confirm that the α-β transition occurs during stretching of TPI that only contains αcrystal(α-TPI). When the stress is relaxed, the β crystal formed during stretching remains, which indicates that the transition is irreversible. On the other hand, stretching of TPI that only contains β crystal(β-TPI) results in orientated β crystal. No β-α transition occurs during stretching. The different structures of stretched α-TPI and β-TPI exclude the previously proposed "melting-recrystallization mechanism". The α-β transition depends significantly on temperature and strain rate, indicating the transition is governed both by thermodynamics and kinetics. Our results support a solid-solid transition mechanism rather than a melting-recrystallization mechanism. The irreversible nature of the transition is attributed to the metastability of the β phase in the unstretched state. Different from the "β phases" that appear in polymers with stress-induced reversible transitions, e.g. poly(butylene terephthalate) and poly(butylene succinate), the stability of β phase in TPI is high that can be *** strain rate dependence of α-β transition hinders the determination of critical stress for the transition. It further indicates that the local stress within the sample is more heterogeneous at higher strain rates.

关键词： Trans-1 4-polyisoprene Crystal transition Deformation Crystallization

Chinese wheat mosaic virus: A long-term threat to wheat in China

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Journal of Integrative Agriculture 2019年第4期18卷 821-829页

作者： guo liu-ming HE Jing LI Jing CHEN Jian-ping ZHANG Heng-mu College of Chemistry and Life Science Zhejiang Normal University State Key Laboratory Breeding Base for Zhejiang Sustain Pest and Disease Control/MOA and Zhejiang Key Laboratory of Plant Protection and Biotechnology Institute of Virology and Biotechnology Zhejiang Academy of Agricultural Sciences

In China, a soil-borne virus causing a disease of winter wheat and associated with Polymyxa graminis, has been reported for many years and is now recognized as a new species, Chinese wheat mosaic virus(CWMV). Since the determination of its genomic sequence, more progress has been made in understanding its genomic structure and functions. Molecular and serological methods have been developed to help survey the distribution of the virus and to provide the basic information needed for disease forecasting and control. At present, the best countermeasure is cultivation of resistant wheat varieties. In addition, development and application of some auxiliary countermeasures, such as rotation of non-host crops, delayed seed-sowing, reasonable application of nitrogen fertilizer, and treatment of imported seeds with fungicides before sowing, may be helpful for controlling the disease. The viral distribution and damage, virion properties, genome organization and spontaneous mutation, temperature sensitivity, and disease management options are here reviewed and/or discussed to help in developing more cost-effective countermeasures to control the disease in the future.

关键词： Chinese wheat mosaic virus(CWMV) Polymyxa graminis disease control genome structure spontaneous mutation temperature sensitivity

A novel and green synthesis of indolone-N-amino acid derivatives via the Passerini three-component reactions in water

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Chinese Chemical Letters 2016年第3期27卷 345-348页

作者： Rong-Kun Li Quan-Li Yang Yi liu Dong-Wei Li Nian-Yu Huang ming-guo liu Hubei Key Laboratory of Natural Products Research and Development College of Biological and Pharmaceutical SciencesChina Three Gorges University

A green Passerini three-component reaction of 2-（4-oxo-4,5,6,7-tetrahydro-1H-indol-1-yl）acetic acid with alkyl or aryl isocyanides and aldehydes was reported under aqueous conditions at 35 ℃ for 1 h, and21 indolone-N-amino acid derivatives were prepared in high yields of 42%–99%. Their structures were characterized by IR, ESI–MS, NMR and elemental analysis, and the possible mechanisms have been also proposed. The highly efficient and eco-friendly method provides a facile access to a library of indoloneN-amino acid derivatives for future research on bioactivity screening.

关键词： Passerini three-component reaction Indolone-N-amino acid Green synthesis Heterocycles Isocyanide

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Chemical Research in Chinese Universities 2001年第2期17卷 212-218页

作者： guo ming and liu Wen-jie (Department of Basic Courses, Tarim University of Agricultural Reclamation, Alar, Xinjiang 843300, P. R. China) Tarim Univ Agr Reclamat Dept Basic Courses Alar 843300 Xinjiang Peoples R China

The molecular similarity of 139 organic compounds was calculated by the topologic index method, the flexible super-ball algorithm was used to scan similar molecules and structures. The results show that the properti... 详细信息

关键词： Molecular similarity Super-ball algorithm Calculation

Research and Practice of Production Technology for High Performance Low Alloy Steels in WISCO

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Journal of Iron and Steel Research International 2011年第S1期18卷 99-103页

作者： FU Lian-chun,guo Ai-ming,liu Ji-bin,guo Bin,CHEN Yan-tang [Wuhan Iron and Steel (Group) Corporation,Wuhan 430080,Hubei,China] Wuhan Iron & Steel Grp Corp Wuhan 430080 Hubei Peoples R China

The product system of high strength low alloy steels (HSLA) produced by Wuhan Iron and Steel (Group) Corporation (WISCO) was presented.A series of high performance structural steels have been developed for important construction projects around the world in different areas,such as bridge,pressure vessel,pipe line,shipbuilding,architecture,machinery and railway *** order to promote the development of large heat input welding steel,high grade thick pipeline steel and long span bridge steel,a lot of advanced production technologies have been achieved through intensive investigation,such as the control of high purity,high homogenization and free defects in steel slabs,the rules of high melting point particle formation and distribution in micro and nano scale during steel production,and the TMCP technology for ultra low carbon bainite steel for medium and heavy *** will carry on research and application of economic and weather-resistant steels and promote the developing and producing technologies of HSLA steel.

关键词： WISCO high performance low alloy steels production technology

Special Issue:The Youth Innovation Promotion Association of the Chinese Academy of Sciences

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Chinese Journal of Polymer Science 2023年第4期41卷 475-475页

作者： guo-ming liu Du-Jin Wang 不详

We are pleased to announce the special issue of the Youth Innovation Promotion Association(YIPA)of the Chinese Academy of Sciences(CAS).Established in 2011,YIPA aims to enhance interaction,encourage interdisciplinary collaboration among members,and promote the career development of young researchers,under the age of *** date,YIPA has more than 5000 regular members and more than 600 advanced members,including many researchers actively working in the polymer field.

关键词： Youth encourage collaboration

Thromboelastography in elective total hip arthroplasty

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World Journal of Orthopedics 2021年第8期12卷 555-564页

作者： Patryck Lloyd-Donald Wen-Shen Lee guo-ming liu Rinaldo Bellomo Larry McNicol Laurence Weinberg Department of Anesthesia Austin HealthHeidelberg 3084VictoriaAustralia Department of Intensive Care Austin HospitalMelbourne 3084VictoriaAustralia Department of Surgery The University of MelbourneAustin HealthMelbourne 3084VictoriaAustralia

BACKGROUND Hypercoagulability plays an important role in predisposing patients to venous thromboembolism(VTE)after total hip arthroplasty(THA).We used thromboelastography(TEG)to examine the coagulation status of patients undergoing *** To examine coagulation as measured by TEG in patients undergoing THA who received standard VTE chemoprophylaxis with *** After ethical approval,we performed a retrospective analysis of data collected in patients undergoing primary elective *** analyzed TEG data on samples performed before skin incision,intraoperatively and for 5 d *** coagulation tests were performed preoperatively and on postoperative day *** Twenty patients undergoing general anesthesia and 32 patients undergoing spinal anesthesia(SA)were *** demonstrated a progressively hypercoagulable state postoperatively,characterized by elevated maximum *** also demonstrated transient intraoperative hypercoagulability in patients receiving *** contrast,conventional coagulation tests were normal in all patients,pre-and postoperatively,except for an increase in plasma fibrinogen day 5 *** Despite VTE prophylaxis,patients following total hip replacement remain in a hypercoagulable state as measured by both TEG and conventional *** group may benefit from more optimal anticoagulation and/or additional perioperative hemostatic monitoring,via TEG or otherwise.

关键词： Surgery Orthopedic Anesthesia Hip arthroplasty Hypercoagulability Thrombelastography

Changes of Endogenous Hormone Contents in Fruit, Seeds and Their Effects on the Fruit Development of Rosa roxburghii

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Agricultural Sciences in China 2003年第12期2卷 1376-1381页

作者： FAN Wei-guo, AN Hua-ming, liu guo-qin, HE Song-tao and liu Jin-ping (Agricultural College, Guizhou University, Guiyang 550025, P. R. China) Agricultural College Guizhou University Guiyang 550025 P. R. China

The fruit of cultivar Guinong5 (Rosa roxburghii Tratt.) was used to investigate the regularity of its growth and development, and the changes of endogenous hormone contents during the period of the growth and development. The result showed that contents of GA 1+3, IAA and ZRs in the flower receptacle of young fruit were high and then decreased, contents of GA 1+3and IAA in seeds increased with its development until maturity. The contents of ZRs and ABA in the flower receptacle of young fruits and seeds were high, and then had a tendency of descent with the development of fruits. The contents of GA 1+3, IAA, ZRs and ABA in flower receptacle of young fruit with normal fertilization were much higher than those of in non-fertilization fruits. In the flower receptacle of malformed fruits, the contents of GA 1+3, IAA and ZRs in normally developing flower receptacle were significantly higher than those in malformed fruits. The growth and development of fruits depended largely on the seeds, development because the seeds in the fruits with non-fertilization failed to be formed or even formed but irreproducible, which would lead to the decrease of GA 1+3, IAA contents and the abnormal development of fruits. Therefore the fruits deformed and dropped inevitably.

关键词： Rosa roxburghii Tratt. Fruit growth and development Endogenous hormones