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Effect of CXCR4 pretreated with ultrasound-exposed microbubbles on accelerating homing of bone marrow mesenchymal stem cells to ischemic myocardium in AMI rats

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Asian Pacific Journal of Tropical Medicine 2015年第9期8卷 751-756页

作者： Jun-Yi Gu Hui-Fen Shi xiu-Li Gao qing-qing Ma Bo Zhang Department of Ultrasound in Medicine East Hospital Tongji University School of Medicine

Objective: To investigate the role and potential mechanism of CXCR4 in promoting targeted homing of bone marrow mesenchymal stem cells(BMSCs) with ultrasound-exposed microbubbles(UM) pretreatment. Methods: Third generation BMSCs were divided into four groups control group, ultrasound(US) group, UM group and ultrasound-exposed microbubbles plus catalase group. RT-PCR and western blot were performed to determine the levels of CXCR4 m RNA transcription and protein expression, respectively. Third generation BMSCs were labeled with Fluo-α/AM and divided into three groups: control group, US group and UM group, and flurorescence intensities in the cells were observed immediately, 5 min and 15 min after intervention underflurorescence microscope. The calcium iron levels in the cells were analyzed. BMSCs were divided into i ve group: group A without calcium in the medium, group B, group C, group D and group E containing calcium chloride with concentration of l mol, 2 mol, 4mol, anti-calciurn-sensing receptor antibody, respectively. RT-PCR and western blot were performed to determine the levels of CXCR4 m RNA transcription and proteins expression of the third generation BMSCs of each group, respectively. Results: The levels of CXCR4 m RNA transcription and protein expression between US group and control group had no statistically signii cant dif erence(P>0.05) shown by RT-PCR and western blot; the transcription level in the UM group was signii cantly higher than that in US group and control group(P0.05), which in the cells of UM group was signii cantly higher than that in the cells of both US group and control group(P<0.05). Compared to group A, expressions of CXCR4 of group B to D were signii cantly increased in

关键词： Ultrasound-exposed microbubbles Bone marrow mesenchymal stem cells CXCR4 Calciumion

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Synthesis and Characterization of Ion-exchange Sulfonated Poly (ether sulfone)

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Chinese Chemical Letters 2006年第4期17卷 447-448页

作者： Fan xiu MENG Chun qing ZHANG Lian LIU Yuan Yuan ZHANG Department of Polymer Materials Science School of Chemical Engineer Dalian University of Technology Dalian 116012

N,N＇-Bis（3-hydroxyphenyl）-1,8,4,5-naphthalenetetracarboxylic bisimide was prepared from the reaction of 1,8,4,5-naphthalenetetrcarboxylic acid dianhydride and 2-aminophenol in N, N-dimethylformamide. Polymerization of this bisimide with 4,4＇-difluorodiphenylsulfone and disodium 3,3＇-disulfonate4,4＇-difluorodiphenylsulfone gave ion-exchange sulfonated poly（ether sulfone）. The structure of the title compound was characterized with H-NMR and its polymer was characterized with FT-IR.

关键词： Bisimide ion-exchange polymer sulfonated poly(ether sulfone).

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Preparation of High-performance Polyimide Fibers with Wholly Rigid Structures Containing Benzobisoxazole Moieties

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Chinese Journal of Polymer Science 2022年第3期40卷 280-289,I0007页

作者： Yu-Ting Fang Feng Gan Jie Dong Xin Zhao xiu-Ting Li qing-Hua Zhang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China School of Textile Materials and Engineering Wuyi UniversityJiangmen 529020China

In this work, a fully rigid coplanar symmetric heterocyclic unit was introduced into the rigid polyimide macromolecular backbone structure to prepare high-performance polyimide fibers. The novel co-polyimide(co-PI) fibers based on 3,3',4,4'-biphenyltetracarboxylic anhydride(BPDA), p-phenylenediamine(PDA) and 2,6-(4,4'-diaminodiphenyl) benzo[1,2-d:5,4-d'] bisoxazole(PBOA) were fabricated via a twostep wet-spinning method. The effects of benzobisoxazole moiety on spinnability, aggregation structure, and mechanical properties of fibers were systematically discussed. The detailed structural analysis revealed that the well-defined aggregation structures of co-PI fibers were obtained from initial amorphous structure when post hot-drawing temperature was higher than 460 ℃ under proper drawing ratio, and the incorporation PBOA into BPDA-PDA structures produced more compact structural co-PI fiber than homo BPDA-PDA fiber. The BPDA-PDA/PBOA co-PI fibers exhibited optimum tensile strength and modulus of 2.65 and 103 GPa, which increased by 182% and 84% compared to the homo BPDA-PDA fiber, respectively.

关键词： Polyimide fiber Benzobisoxazole Co-polymerization Microstructure Mechanical properties

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Dry-spun Polyimide Fibers with Excellent Thermal Stability,Intrinsic Flame Retardancy and Ultralow Smoke Release

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Chinese Journal of Polymer Science 2022年第11期40卷 1422-1431页

作者： Han Dong Yu-Ping Wang xiu-Ting Li Xin Zhao Jie Dong qing-Hua Zhang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai201620China Jiangsu New Vision Advanced Functional Fiber Innovation Center Co. Ltd.Suzhou215000China

Polymer fiber with an ultrahigh thermal stability,superior flame retardancy and low smoke release during combustion is urgently needed and a crucial challenge for developing advanced fireproof *** this study,a series of high-performance polyimide fibers are synthesized by copolymerizing 4,4'-diaminodiphenylmethane(MDA)into the pyromellitic dianhydride-p-phenylenediamine(PMDA-PDA)backbone for synergistically solving the technical challenge of poor fiber processing ability of these polyimides with a high inherent molecular *** glass transition temperature(Tg)of resultant fibers with the PDA molar ratio over 50 mol%reaches above 420℃ and their 10 wt%weight loss temperature(T10%)is within 543-633℃.For the typical fiber containing 80 mol%of PDA,the limiting oxygen index(LOI)reaches 39%and exhibits a rapid self-extinguishing performance after deviating from the ***,this fiber exhibits the minimum heat release rate of 14.1 kW/m^(2) in a long ignition time of 813 s during combustion,revealing its better flame retardancy than the well-known Nomex fiber with a heat release rate of 140.6 kW/m^(2) during the 120 s ***,the total smoke production of this polyimide fiber is only 1/9 of the Nomex ***,the excellent flame retardancy of polyimide fibers indicating them more attractive as the fireproof materials in the field of emergency protection.

关键词： Polyimide fiber Copolymerization Thermal stability Flame retardancy Smoke release

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Mathematical model of burden distribution in bell-less top blast furnace

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Journal of Iron and Steel Research International 2023年第2期30卷 216-226页

作者： Jian-sheng Chen Hai-bin Zuo Jing-xiu Wang qing-guo Xue Jing-song Wang State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China

The burden distribution in the shaft of blast furnace is known to affect the gas distribution,heat transfer,and chemical reactions inside the ***,the internal layer structure of burden in the shaft cannot be directly ***,a mathematical model for evaluating burden profile and layer structure was established.A sensitivity analysis based on the model was implemented to elucidate the effect of some factors on the burden distribution,including the stockline height and the mass of central *** results show that the width of funnel zone widens with the increase in stockline height,and the mass percentage of ore to coke in this zone slightly ***,the mass of central coke shows a significant influence on the width of coke channel,and 2%of batch mass of coke is recommended to implement central coke charging *** model has been indirectly verified by the gas temperature in operating blast furnace and successfully applied to online evaluate burden distribution.

关键词： Blast furnace Burden distribution Mathematical model Stockline height Central coke

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Numerical analysis of carbon saving potential in a top gas recycling oxygen blast furnace

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Journal of Iron and Steel Research International 2017年第6期24卷 608-616页

作者： Xue-feng She xiu-wei An Jing-song Wang qing-guo Xue Ling-tan Kong State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China qingdao Special Steel Company Limited Shandong Qingdao 266409 Shandong China

Aiming at the current characteristics of blast furnace （BF） process, carbon saving potential of blast furnace was investigated from the perspective of the relationship between degree of direct reduction and carbon consumption. A new relationship chart between carbon consumption and degree of direct reduction, which can reflect more real situation of blast furnace operation, was established. Further- more, the carbon saving potential of hydrogen-rich oxygen blast furnace （OBF） process was ana- lyzed. Then, the policy implications based on this relationship chart established were suggested. On this basis, the method of improving the carbon saving potential of blast furnace was recycling the top gas with removal of CO2 and H2O or increasing hydrogen in BF gas and full oxygen blast. The results show that the carbon saving potential in traditional blast furnace （TBF） is only 38 56 kg · t ^-1 while that in OBF is 138 kg · t ^-1. Theoretically, the lowest carbon consumpt!on of OBF is 261 kg · t ^-1 and the corresponding degree of direct reduction is 0.04. In addition, the theoretical lowest carbon consumption of hydrogen-rich OBF is 257 kg · t ^-1. The modeling analysis can be used to estimate the carbon savings potential in new ironmaking process and its related CO2 emissions.

关键词： Blast furnace processDirect reduction degreeCarbon consumptionDirect reductionCarbon saving potentiaOxygen blast furnace

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Soil Organic Nitrogen and Its Contribution to Crop Production

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Journal of Integrative Agriculture 2014年第10期13卷 2061-2080页

作者： LI Sheng-xiu WANG Zhao-hui MIAO Yan-fang LI Shi-qing College of Natural Resources and Environment Northwest A&F University School of Agriculture Henan University of Science and Technology State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F University

Plant growth and crop production depend to a large extent on soil N supplying capacity （SNSC）： The higher the SNSC, the higher the dependence of crops on soil and the lower the N fertilizer recovery. Of the SNSC, soil organic N （ON） played a key role in supplying N nutrient to crop production and still does in many subsistence and low-input farming systems. In this paper, soil ON contents, types, chemical components and its contribution to plant production are reviewed up to date in details, the characteristics of ON in dryland soils discussed together with its chemical components, and the mineralization and availability to plants of some important chemical components are emphasized at the last part for practical considerations.

关键词： organic nitrogen in soil chemical components soil N supplying capacity mineralization contribution

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Study on the surface properties of surface modified silicone intraocular lenses

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International Journal of Ophthalmology(English edition) 2012年第1期5卷 84-87页

作者： Gui-Qin Wang Han-qing Gu and xiu-Jun Peng Department of Ophthalmology the Naval General Hospital Beijing 100048 China

AIM: To prepare a new-type soft intraocular lens (IOL) that silicone intraocular lenses (IOLs) were modified by surface modification technique to assess IOLs biocompatibility. METHODS: With the technique of ion beam combined with low temperature and low pressure plasma, the surface characteristics of the IOLs including physical and optical properties were determined by the instruments of IOLs resolution, UV/VIS scanning spectrophotometer, contact angle measurement system, electron spectroscopy for chemical analysis (ESCA) and scanning electron microscope (SEM). RESULTS: The color of titanium (Ti) modified IOLs was light yellow and that of titanium nitride (TiN) modified IOLs was light brown. The absorptive degree of ultraviolet rays and the hydrophilicity of the surfaces of modified IOLs were increased, and appeared suitable chemical compositions. The resolution of unmodified and modified IOLs reached normal standard. The surfaces of unmodified and Ti-modified IOLs appeared uniform. The surfaces of TIN-modified IOLs presented fine porcelain structure. CONCLUSION: The optical properties of all IOLs and the surface morphology of the modified IOLs were not affected by modification processes. The surface properties of the modified IOLs were improved.

关键词： silicone intraocular lenses surface modification technique surface property biocompatibility

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Hydrothermal Synthesis and Crystal Structure of a Cadmium(II) Polymer with One-dimensional Chain Structure: [Cd(bpy)(BDC)]_n·nbpy

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Chinese Journal of Structural Chemistry 2007年第5期26卷 537-540页

作者： LI xiu-Mei NIU Yan-Ling WANG qing-Wei CUI Yun-Cheng LIUBo Department of Chemistry Tonghua Teachers College Tonghua Jilin 134002 China Jilin Normal University Siping Jilin 136000 China

A metal-organic coordination polymer [Cd（bpy）（BDC）]n·nbpy （bpy = 2,2-bipyri-dine, H2BDC = terephthalic acid） has been hydrothermally synthesized and structurally characterized by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The complex crystallizes in monoclinic, space group C2/c with a = 15.723（5）, b = 21.695（5）, c = 7.576（5） A, β = 116.171（7）°, V = 2319.3（18）A^3, C28H20CdN4O4, Mr = 588.88, Dc = 1.686 g/cm^3, μ（MoKα） = 0.987 mm^-1, F（000） = 1184, Z = 4, the final R = 0.0464 and wR = 0.0831 for 1882 observed reflections （Ⅰ〉 2σ（Ⅰ））. It exhibits a three-dimensional network with channels constructed from one-dimensional coordination chains via C–H…O hydrogen bonds and significant aromatic π-π stacking interactions.

关键词： hydrothermal synthesis crystal structure coordination polymer

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Investigation on influencing factors of 5-HMF content in Schisandra

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第6期8卷 439-445页

作者： XU qing LI Ying-hua LU xiu-yang Institute of Pharmaceutical Engineering Zhejiang University Hangzhou 310027 China Department of Internal Medicine Hospital of Zhejiang University Hangzhou 310027 China

In order to investigate the influencing factors of 5-hydroxymethyl-2-furaldehyde （5-HMF） content in Schisandra, confirm the theory of 5-HMF deriving mainly from Schisandra processing course, and give some suggestions about the Schisandra processing method, the 5-HMF contents in decoctions of Schisandra under different heating temperature, decocting time, soaking time, processing methods and treatment with different solvents before decocting the Schisandra were measured by RP-HPLC method. The results showed that there is great difference of 5-HMF level in decoctions from differently processed Schisandra and unprocessed Schisandra; decocting time of 60 rain has some effects on 5-HMF level in decoctions and there is certain quantity 5-HMF in processed Schisandra itself and very little 5-HMF in unprocessed Schisandra. Heating time, heating temperature and treating solvents all have effect on 5-HMF level in decoction of Schisandra. 5-HMF in Schisandra was mainly from processing course. Both long heating time and high heating temperature can increase 5-HMF level in Schisandra. The production of 5-HMF in Schisandra may have some relationships with some polar components, which can dissolve in water, ethanol and acetone, especially in ethanol. To control processing temperature, processing time and treatment with some solvent is very important for controlling 5-HMF level in Schisandra.

关键词： Schisandra process Heating temperature Heating time 5-Hydroxymetyl-2-furaldehyde (5-HMF)

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