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Chinese Journal of Polymer Science 2015年第9期33卷 1294-1304页

作者： Qian Xing Rong-bo Li 董侠 Xiu-qin Zhang Liao-yun Zhang du-jin wang School of Chemistry and Chemical Engineering University of Chinese Academy and Sciences Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Engineering Plastics Institute of Chemistry Chinese Academy of Sciences Petrochina Petrochemical Research Institute

Polyester-based biodegradable polyurethane （PU） with different hard segment ratios was selected to modify the impact toughness of poly（L-lactide）（PLLA）. The influence of blending composition and hard segment ratio of PU on the phase morphology, crystallization behavior and mechanical properties of PLLA/PU blends has been investigated systematically. The results showed that the PU particles were uniformly dispersed in PLLA matrix at a scale from sub- microns to several microns. The glass transition temperature of PU within these blends decreased compared to that of neat PU, but rose slightly with its content and hard segment ratio. The presence of PU retarded the crystallization ability of PLLA, whereas enhanced its elongation at break and impact resistance effectively. As the PU content reaches up to 30 wt%, the phenomenon of brittle-ductile transition occurred, resulting in a rougher fracture surface with the formation of fibril-like structure. Moreover, under the same concentrations, the elongation at break and impact strength of PLLA blends decreased slightly with the increase of hard segment ratio of PU.

关键词： Poly(L-lactide) Polyurethane Phase morphology Impact modification Hard segment ratio.

Fingerprinting Analysis of Rhizoma Chuanxiong of Commercial Types using ~1H Nuclear Magnetic Resonance Spectroscopy and High Performance Liquid Chromatography Method

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Journal of Integrative Plant Biology 2009年第6期51卷 537-544页

作者： Hai-Lin Qin An-Jun Deng Guan-Hua du Peng wang jin-Lan Zhang Zhi-Hong Li Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Key Laboratory of Bioactive Substances and Resources of Chinese Herbal Medicine Ministry of Education Beijing 100050 China

The ^1 H nuclear magnetic resonance （^1 H NMR） fingerprints of fractionated non-polar extracts （control substance for a plant drug （CSPD） A） from Rhizoma chuanxiong, the rhizomes of Ligusticum chuanxiong Hort., of seven specimens from different sources were measured on Fourier Transform （FT）-NMR spectrometer and assigned by comparing them with the ^1 H NMR spectra of the isolated pure compounds. The ^1 H NMR fingerprints showed exclusively characteristic resonance signals of the major special constituents of the plant. Although the differences in the relative intensity of the ^1H NMR signals due to a discrepancy in the ratio of the major constituents among these samples could be confirmed by high performance liquid chromatography analysis, the general features of the ^1H NMR fingerprint established for an authentic sample of the rhizomes of L. chuanxiong e. hibited exclusive data from those special compounds and can be used for authenticating L. Chuanxiong species.

关键词： control substance for a plant drug A ^1 H nuclear magnetic resonance fingerprint high performance liquid chromatography Ligusticumchuanxiong phenylpropenoid phthalides.

The Crystallization Behavior Regulating Nature of Hydrogen Bonds Interaction on Polyamide 6,6 by Poly(vinyl pyrrolidone)

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Chinese Journal of Polymer Science 2023年第3期41卷 394-404,I0008页

作者： Yang Liu Li Peng Jie-Long Lin Yong Zhou du-jin wang Charles C.Han Xian-Bo Huang Xia Dong National-certified Enterprise Technology Center Kingfa Science and Technology Co.LTD.Guangzhou 510663China CAS Key Laboratory of Engineering Plastics Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBejing 100190China University of Chinese Academy of Sciences Beijing 100049China

The crystallization behavior of polyamide 6,6(PA66) under complex flow field is of great importance for its final mechanical ***(vinyl pyrrolidone)(PVP) was applied as crystallization modifying agency to improve processability of *** regulation nature on hydrogen bonds(H-bonds) interaction of PVP was studied upon cooling *** revealed by in situ FTIR,the sample with 5 wt% PVP displays decreased enthalpy change(ΔH) for both the generation of H-bonds and the transition of H-bonds from “disordered” to “ordered” state,which illustrates the molecular mechanism for the regulation of crystallzation ***,2D-WAXD is applied to reveal the evolution of microstructure for sample under external injection *** orientation factor(f_(H)) decreases obviously with the addition of PVP,because the relaxation of chain segments is promoted as well the crystallization is *** above crystallization and microstructure changes during the processing provokes the improvement of processability without the apparent sacrifice of mechanical properties.

关键词： Polyamide 66 Poly(vinyl pyrrolidone) Hydrogen bonds interaction

Investigation on structural changes of isotactic polypropylene mesophase in the heating process by using two-dimensional infrared correlation spectroscopy

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Chinese Chemical Letters 2015年第2期26卷 197-199页

作者： Qian-Hong Jiang Chun-Bo Zhang Jian Yang Ying Zhao Yi-Zhuang Xu du-jin wang Beijing National Laboratory for Molecular Sciences Key Laboratory of Engineering PlasticsInstitute of ChemistryChinese Academy of Sciences College of Chemistry and Molecular Engineering Peking University

Two-dimensional FT-IR correlation spectroscopy was used to reveal the structural changes of isotactic polypropylene（iPP） mesophase during the heating *** co-relationship among the regular helical bands of iPP was discussed according to synchronous *** results show that the segments with different length-helixes were found to undergo a disordered process in the temperature range of 25-60 ℃.

关键词： 2D-IR Isotactic polypropylene Mesophase

Effect of ginsenoside Rg1 on hematopoietic stem cells in treating aplastic anemia in mice via MAPK pathway

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World Journal of Stem Cells 2024年第5期16卷 591-603页

作者： jin-Bo wang Ming-Wei du Yan Zheng Internal Medicine of Traditional Chinese Medicine Tongde Hospital of Zhejiang ProvinceHangzhou 310012Zhejiang ProvinceChina Institute of Cardiovascular Disease Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China Shanghai Key Laboratory of Molecular Medical Mycology Second Affiliated Hospital of Naval Medical UniversityShanghai 200003China Shanghai Key Laboratory of Traditional Chinese Clinical Medicine Shanghai 201203China Department of Hepatic The Xixi Hospital of Hangzhou Affiliated to Zhejiang University of Traditional Chinese MedicineHangzhou 310023Zhejiang ProvinceChina

BACKGROUND Aplastic anemia(AA)presents a significant clinical challenge as a life-threatening condition due to failure to produce essential blood cells,with the current the-rapeutic options being notably *** To assess the therapeutic potential of ginsenoside Rg1 on AA,specifically its protective effects,while elucidating the mechanism at *** We employed a model of myelosuppression induced by cyclophosphamide(CTX)in C57 mice,followed by administration of ginsenoside Rg1 over 13 *** invest-igation included examining the bone marrow,thymus and spleen for pathological changes via hematoxylin-eosin ***,orbital blood of mice was collected for blood routine *** cytometry was employed to identify the impact of ginsenoside Rg1 on cell apoptosis and cycle in the bone marrow of AA ***,the study further evaluated cytokine levels with enzyme-linked immunosorbent assay and analyzed the expression of key proteins in the MAPK signaling pathway via western *** Administration of CTX led to significant damage to the bone marrow’s structural integrity and a reduction in hematopoietic cells,establishing a model of *** Rg1 successfully reversed hematopoietic dysfunction in AA *** comparison to the AA group,ginsenoside Rg1 provided relief by reducing the induction of cell apoptosis and inflammation factors caused by ***,it helped alleviate the blockade in the cell *** with ginsenoside Rg1 significantly alleviated myelosuppression in mice by inhibiting the MAPK signaling *** This study suggested that ginsenoside Rg1 addresses AA by alleviating myelosuppression,primarily through modulating the MAPK signaling pathway,which paves the way for a novel therapeutic strategy in treating AA,highlighting the potential of ginsenoside Rg1 as a beneficial intervention.

关键词： Aplastic anemia Ginsenoside Rg1 Myelosuppression MAPK signaling pathway Bone marrow Hematopoietic stem cells

Crosslinking Kinetics of Polyethylene with Small Amount of Peroxide and Its Influence on the Subsequent Crystallization Behaviors

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Chinese Journal of Polymer Science 2016年第9期34卷 1117-1128页

作者：牛艳华 Wen-bin Liang Yin-ling Zhang Xue-lian Chen Shih-yaw Lai Guang-xian Li du-jin wang College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering of ChinaSichuan UniversityChengdu 610065China Performance Material Center National Institute of Clean-and-low-carbon Energy(NICE)Beijing 102209China CAS Key Laboratory of Engineering Plastics Beijing National Laboratory for Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

Crosslinking reactions of high density polyethylene with low peroxide concentrations ranging from 0.1 wt% to 1.0 wt% at temperatures of 170, 180 and 190 ℃ were monitored by rheological measurements. A critical gel forms at the peroxide concentration of 0.2 wt%, where the transition from long chain branching generation to crosslinking network formation could occur. Rheokinetics of crosslinking can be fitted well by Ding-Leonov＇s model. The curing rate k2 at the earlier stage exhibits about 3 times acceleration per 10 ~C with increasing temperature, while the equilibrium modulus G＇ at the fully cured stage is almost independent of temperature. Influences of crosslinking on the subsequent crystallization behaviors were detected by DSC measurements. Above the critical gel concentration, crystallization is largely retarded as evidenced by the lower crystallization temperature Tc and crystallinity Xc due to the network formation. The secondary crystallization valley located at the temperature near 80 ℃ can be observed above the critical concentration, which becomes more evident with the increasing peroxide concentration and curing temperature. This phenomenon provides another evidence of crystallization retardation by the crosslinking network.

关键词： Polyethylene Rheology Crosslinking kinetics Crystallization.

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

Possibility and stabilizing effect of Mo clusters in the Ni-based single-crystal superalloy

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Communications in Theoretical Physics 2024年第8期76卷 187-192页

作者： Yiqun du Huixin jin Rongkai Kang Boya Zhang Han wang Jianxin Zhang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJinan 250061China Department of Materials Science and Technology Tokyo University of ScienceTokyo 1258585Japan

Nickel-based single-crystal superalloys are crucial materials for the preparation of aero-engine turbine blades. Many solute elements are added to superalloys for strengthening. However, the relationship between the clustering behavior of solute atoms and the properties of nickel-based single-crystal superalloys is still unclear. Herein, we conduct first-principles calculations onγ phases with Mo-Mo and Mo-Mo-Ru clusters to reveal the possibility and stabilizing mechanism of solute clusters. Introducing Mo lowers the total energy, binding energy, and formation energy of the γ phase due to the replacement of weak Ni-Ni interaction with strong Mo-Ni bonding. Note that the γ phase containing the Mo-Mo cluster is more stable than that containing a Mo single atom, possibly owing to a wide affecting range. The Ru atom added to the γ phase can further boost system stability, and it tends to form a Mo-Mo-Ru cluster. The stabilizing impact of the Mo-Mo-Ru cluster is demonstrated to be the replacement of weak Ni-Mo interaction by the strong Ru-Mo interaction, which may be derived from the enhanced d-orbital hybridization.

关键词： density functional theory superalloys solute cluster

PRELIMINARY INVESTIGATION ON THE MISCIBILITY OF ISOTACTIC POLYPROPYLENE (iPP) AND SYNDIOTACTIC POLYPROPYLENE (sPP) BLENDS

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Chinese Journal of Polymer Science 2006年第6期24卷 569-573页

作者： Chun-xiao Zheng Xiu-qin Zhang Joerg Rottstegge Xia Dong Ying Zhao du-jin wang Shan-nong Zhu Zhi-gang wang Charles C. Han duan-fu Xu Key Laboratory of Engineering Plastics Joint Laboratory of Polymer Science and Materials Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China State Key Laboratory of Polymer Physics and Chemistry Joint Laboratory of Polymer Science and Materials Institute of Chemistry Chinese Academy of Sciences Beo＇ing 100080 China Graduate School of Chinese Academy of Sciences Beijing 100080 China

Experimental miscibility studies were performed on different compositions of iPP/sPP blends, where sPP has a low syndiotacticity （[rrrr] = 81%）. Combining optical microscopy, rheology, and solid state NMR spectroscopy, the miscibility of the blends was investigated at different scales in the traditionally thought to be ＂immiscible＂ iPP/sPP blends. For the composition of iPP/sPP （90/10） blend, it shows to be miscible in the melt, and furthermore, the existence of intermolecular chain interactions between sPP and iPP components was detected in the solid state.

关键词： iPP/sPP blends Miscibility Optical microscopy Rheology Solid state NMR spectroscopy.

Simulation of gas-solid flow characteristics of the circulating fluidized bed boiler under pure-oxygen combustion conditions

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Chinese Journal of Chemical Engineering 2024年第6期70卷 9-19页

作者： Kaixuan Gao Xiwei Ke Bingjun du Zhenchuan wang Yan jin Zhong Huang Yanhong Li Xuemin Liu Key Laboratory of Special Equipment Safety and Energy-Saving for State Market Regulation China Special Equipment Inspection&Research InstituteBeijing 100029China Department of Energy and Power Engineering Tsinghua UniversityBeijing 100084China School of Electrical and Power Engineering Taiyuan University of TechnologyTaiyuan 030024China

Under the pressure of carbon neutrality,many carbon capture,utilization and storage technologies have witnessed rapid development in the recent years,including oxy-fuel combustion(OFC)***,the conventional OFC technology usually depends on the flue gas recirculation system,which faces significant investment,high energy consumption,and potential low-temperature corrosion *** these deficiencies,the direct utilization of pure oxygen to achieve particle fluidization and fuel combustion may reduce the overall energy consumption and CO_(2)-capture *** this paper,the fundamental structure of a self-designed 130 t·h^(-1) pure-oxygen combustion circulating fluidized bed(CFB)boiler was provided,and the computational particle fluid dynamics method was used to analyze the gas-solid flow characteristics of this new-concept boiler under different working *** results indicate that through the careful selection of design or operational parameters,such as average bed-material size and fluidization velocity,the pure-oxygen combustion CFB system can maintain the ideal fluidization state,namely significant internal and external particle ***,the contraction section of the boiler leads to the particle backflow in the lower furnace,resulting in the particle suspension concentration near the wall region being higher than that in the center ***,the upper furnace still retains the classic core-annulus flow *** addition to increasing solid circulation rate by reducing the average bed-material size,altering primary gas ratio and bed inventory can also exert varying degrees of influence on the gas-solid flow characteristics of the pure-oxygen combustion CFB boiler.

关键词： Circulating fluidized bed Pure-oxygen combustion Gas-solid flow characteristics Simulation CO_(2)capture