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Rigid Biphenyl-contained Epoxy Resins with Improved Thermal Resistant Properties

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Chinese Journal of Polymer Science 2017年第11期35卷 1428-1435页

作者： xiao-yan wei Bo-xuan Zhao 尚亚卓程元荣 Key Laboratory for Advanced Materials School of Chemistry & Molecular Engineering East China University of Science and Technology Shanghai Wujing Optoelectronics Sci&Tech Co. Ltd Department of Materials Science Fudan University

Biphenyl-contained monomer of 1,4-bis[2-（3,4-epoxy cyclohexyl ethyl） dimethylsilyl] biphenyl （BP-SiH-EP） was prepared via hydrosilylation reaction of 1,4-bis（dimethylsilyl） biphenyl （BP-SiH） and 1,2-epoxy-4-vinylcyclohexane in the presence of Karstedt＇s catalyst. ^1H-NMR, 13C-NMR and FTIR were used to characterize the structure of the obtained monomer. BP-SiH-EP was then cured by methyl hexahydrophthalic anhydride （MeHHPA） with 1-cyanoethyl-2-ethyl-4- methylimidazole as an accelerator. The polymerization behavior was studied by DSC. The results of DMA measurement demonstrate that the cured BP-SiH-EP/MeHHPA can maintain high storage modulus （〉1 GPa） in a wide range of temperature up to 176 ℃. According to the damping factor curve of DMA, cured BP-SiH-EP/MeHHPA exhibits a high glass transition temperature （Tg） of 192 ℃, which is 20 ℃ higher than that of cured 1,4-bis[2-（3,4-epoxy cyclohexyl ethyl） dimethylsilyl] benzene （DEDSB）/MeHHPA. TGA results show that cured BP-SiH-EP/MeHHPA has good thermal stability （Tso/o = 339 ℃） due to the high heat-resistance of rigid biphenyl group. Moreover, the crosslinking density of cured BP-SiH-EP/MeHHPA should be lower than that of cured DEDSB/MeHHPA estimated from their chemical structures, which conflicts with the calculated results based on the rubber elasticity equation. The inconsistence indicates that the calculated crosslinking densities are not comparable, possibly owing to their differences in the rigidity of polymer chains and intermolecular interaction.

关键词： Epoxy resin Hydrosilylation Biphenyl group Thermal property Crosslinking density

Hydroxysafflor Yellow A Promotes HaCaT Cell Proliferation and Migration by Regulating HBEGF/EGFR and PI3K/AKT Pathways and Circ_0084443

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Chinese Journal of Integrative Medicine 2024年第3期30卷 213-221页

作者： ZHANG Yue xiao yan-wei MA Jing-xin WANG Ao-xue Department of Dermatology the Second Hospital of Dalian Medical UniversityDalianLiaoning Province116021China Department of Cell Biology Dalian Medical UniversityDalianLiaoning Province116044China

Objective:To investigate the effect and possible mechanism of hydroxysafflor yellow A(HSYA) on human immortalized keratinocyte cell proliferation and ***:HaCaT cells were treated with *** proliferation was detected by the cell counting kit-8 assay,and cell migration was measured using wound healing assay and Transwell migration *** mRNA and protein expression levels of heparin-binding epidermal growth factor(EGF)-like growth factor(HBEGF),EGF receptor(EGFR),phosphatidylinositol 3-kinase(PI3K),protein kinase B(AKT),mammalian target of rapamycin(mTOR),and hypoxia-inducible factor-1α(HIF-1α) were detected by quantitative real-time polymerase chain reaction(qRT-PCR) and Western blot,***_0084443-overexpressing HaCaT cells and empty plasmid HaCaT cells were constructed using the lentiviral stable transfection and treated with *** expression of circ_0084443 was detected by ***:HSYA(800 μmol/L) significantly promoted HaCaT cell proliferation and migration(P0.05).Conclusion:HSYA played an accelerative role in HaCaT cell proliferation and migration,which may be attributable to activating HBEGF/EGFR and PI3K/AKT signaling pathways,and had a particular inhibitory effect on the keratinocyte negative

关键词： hydroxysafflor yellow A circ_0084443 heparin-binding epidermal growth factor-like growth factor/epidermal growth factor receptor phosphatidylinositol 3-kinase/protein kinase B

In(OTf)_3 catalyzed allylation reaction of imines with tetraallyltin

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Chinese Chemical Letters 2009年第1期20卷 40-43页

作者： xiao Ning wei Ling yan Liu Bing Wang wei Xing Chang Jing Li The State Key Laboratory Elemento-Organic Chemistry Institute of Elemento-Organic Chemistry Nankai University Tanjin 300071 China

In the presence of catalytic amount of In（OTf）3 （10 mol%）, a series of aldimines reacted with tetraallyltin in a 2：1 molar ratio to afford the corresponding homoallylic amines in good yields. The good atom efficiency was achieved under mild reaction conditions and a new protocol （allyl）4Sn/In（OTf）3 for simple imines was developed.

关键词： Catalytic allylation Aldimine Tetraallyltin In(OTf)3

Self-diffusion coefficients of organic solvents in linear and branched high density polyethylene particles measured by PFG NMR

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Chinese Chemical Letters 2008年第1期19卷 110-114页

作者： xiao wei yan xiao Hong Ren Siegfried Stap Jing Dai Wang Yong Rong yang Department of Chemical Engineering Zhejiang University Hangzhou 310027 China FG Technische Physik ll/Polymerphysik Fakultat fiir Mathematik und Naturwissenschaften Technische Universitiit Ilmenau Postfach 100565 D-98684 Ilmenau Germany Institut fiir Technische Chemie und Makromolekulare Chemie RWTH Aachen University Worringerweg 1 D-52056 Aachen Germany

Pulsed field gradient nuclear magnetic resonance （PFG NMR） has been performed to study the diffusion of organic solvents into semicrystalline polyethylene particles. Self-diffusion coefficients in different domains of the sample can be extracted through a bi- exponential fit to the echo intensity attenuation, which allows the precise determination of the tortuosity of the polyethylene particles. Further exploration comes from the measurements with branched polyethylene particles and it was found that the diffusion in polymer phase contributed significantly to the slow component of the exponential decay curve. 2007 Jing Dai Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Self-diffusion coefficients Pulsed field gradient NMR Tortuosity Polyethylene particle

Characteristics of Titanocene Catalyst Supported on Palygorskite for Ethylene Polymerization

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Chinese Chemical Letters 2006年第5期17卷 653-656页

作者： xiao wei yan Jing Dai WANG Yi Bing SHAN Yong Rong yanG Department of Chemical Engineering Zhejiang University Hangzhou 310027

A series of heterogeneous catalysts with Cp2TiCl2 supported on palygorskite were prepared and evaluated by ethylene slurry polymerizations. The so-called direct supported catalyst, for which the pretreatment of palygorskite with MAO or Al（i-Bu）3 was not necessary, gave the highest activity among these supported catalysts and could be more robust than homogeneous Cp2TiCl2. With the direct supported catalyst, no significant activity loss was observed under low Al/Ti molar ratios （Al/Ti=300） and the decay of polymerization rate was slower when compared to the other supported catalysts. It was found that the surface Lewis acidity of palygorskite after thermal treatment played an important role in activation of metallocene compound and resulted in high catalyst activity.

关键词： Playgorskite supported catalyst ethylene polymerization Lewis acidity.

Impact of continuous care on cardiac function in patients with lung cancer complicated by coronary heart disease

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World Journal of Clinical Cases 2024年第2期12卷 314-321页

作者： Ting Gao Jin-Lan Luo Pan Guo Xi-Wen Hu xiao-yan wei yan Hu Division of Cardiovascular First Ward Department of Internal MedicineLiyuan HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430077Hubei ProvinceChina Department of Cardiovascular Medicine Wuhan Wuchang HospitalWuhan 430063Hubei ProvinceChina Cardiovascular Clinical Medical Center Liyuan HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430077Hubei ProvinceChina Department of Second Thoracic Surgery Hubei Cancer HospitalWuhan 430079Hubei ProvinceChina

BACKGROUND Despite sharing similar pathogenic factors,cancer and coronary heart disease(CHD)occur in comparable populations at similar ages and possess similar susceptibility ***,it is increasingly commonplace for patients to experience the simultaneous occurrence of cancer and CHD,a trend that is steadily *** To determine the impacts of continuing care on lung cancer patients with CHD following percutaneous coronary intervention(PCI).METHODS There were 94 lung cancer patients with CHD following PCI who were randomly assigned to the intervention group(n=38)and the control group(n=41).In the intervention group,continuing care was provided,while in the control group,routine care was *** evaluation of cardiac and pulmonary function,medication compliance,a 6-min walk test,and patient quality of life was *** Differences between the two groups were significant in left ventricular ejection fraction,6-min walk test,oxygen uptake,quality of life and medication compliance(P<0.05).In comparison with the control group,the enhancement in the intervention group was more *** intervention group had more patients with high medication compliance than the control group,with a statistically significant difference(P<0.05).CONCLUSION After undergoing PCI,lung patients with CHD could benefit from continued care in terms of cardiac and pulmonary function,medications compliance,and quality of life.

关键词： Lung cancer Continuing care Coronary heart disease Percutaneous coronary intervention

Estimation of Aqueous Solubility (-lgS_w) of All Polychlorinated Biphenyl (PCB) Congeners by Density Functional Theory and Position of Cl Substitution (NPCS) Method

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Chinese Journal of Structural Chemistry 2007年第5期26卷 519-528页

作者： wei xiao-yan GE Zhi-Gang WANG Zun-Yao XU Jiao School of Biological and Chemical Engineering Jiaxing University Jiaxing Zhejiang 314001 China

Optimization calculations of 209 polychlorinated biphenyls （PCBs） were carried out at the B3LYP/6-31G^＊ level. It was found that there is significant correlation between the Cl substitution position and some structural parameters. Consequently, Cl substitution positions were taken as theoretical descriptors to establish a novel QSPR model for predicting –lgSw of all PCB congeners. The model achieved in this work contains four variables, of which r^2 = 0.9527, q^2 = 0.9490 and SD = 0.25 with large t values. In addition, the variation inflation factors （VIFs） of variables in this model are all less than 5.0, suggesting high accuracy of the –lgSw predicting model. And the results of cross-validation test and method validation also show that the model exhibits optimum stability and better predictive capability than that from the AM1 method.

关键词： polychlorinated biphenyls (PCBs) aqueous solubility (-lgSw) quantitativestructure-property relationship (QSPR) position of Cl substitution (NPCS) method

Calculating magnetic shielding effectiveness for high-power dc comparator by magnetic circuit method

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Journal of Chongqing University 2007年第2期6卷 113-118页

作者： WANG xiao-wei REN Shi-yan School of Electrical and Electronics Engineering Huazhong University of Science ＆ Technology Wuhan 430074 P.R. China

Magnetic shielding is very important in the design of a high-power dc comparator. This paper addressed the application of magnetic circuit method to calculate the magnetic shielding effectiveness of high-power dc comparators when an external radial magnetic field is added. The mathematical relationship between the magnetic shielding effectiveness and the parameters of the magnetic shielding body were obtained. To verify the validity of the calculation method, we developped a procedure to measure the magnetic shielding effectiveness of the magnetic body by measuring the induction voltage of the detection winding instead of the magnetic intensity at a point in the magnetic shielding body, making the manipulation much easier. The result calculated with the magnetic circuit method turns out to be closer to the measured one compared with that calculated with a conventional algorithm proposed by Ren, suggesting that the magnetic circuit method is an applicable tool for estimating the toroidal cavity magnetic shielding effectiveness of a heavy current comparator when a radial magnetic field is added.

关键词： radial magnetic field magnetic shielding effectiveness magnetic circuit analysis method magnetic potential

Retrospective Examination of Q Fever Endocarditis： An Underdiagnosed Disease in the Mainland of China

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Chinese Medical Journal 2017年第1期130卷 64-70页

作者： xiao Han Jeffrey Hsu Qi Miao Bao-Tong Zhou Hong-wei Fan xiao-Lu Xiong Bo-Hai Wen Lian Wu xiao-wei yan Quan Fang wei Chen Department of Hematology Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100730 China Department of Cardiology Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100730 China Department of Cardiac Surgery Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100730 China Department of Infection Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100730 China ing 100071 China Department of Internal Medicine Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100730. China

Background： Q fever endocarditis, a chronic illness caused by Coxiella burnetii, can be fatal ifmisdiagnosed or left untreated. Despite a relatively high positive rate of Q fever serology in healthy individuals in the mainland of China, very few cases of Q fever endocarditis have been reported. This study summarized cases of Q fever endocarditis among blood culture negative endocarditis （BCNE） patients and discussed factors attributing to the low diagnostic rate. Methods： We identified confirmed cases of Q fever endocarditis among 637 consecutive patients with infective endocarditis （IE） in the Peking Union Medical College Hospital between 2006 and 2016. The clinical findings for each confirmed case were recorded. BCNE patients were also examined and each BCNE patient＇s Q fever risk factors were identified. The risk factors and presence of Q fever serologic testing between BCNE patients suspected and unsuspected of Q fever were compared using the Chi-squared or Chi-squared with Yates＇ correction for continuity. Results： Among the IE patients examined, there were 147 BCNE patients, of whom only 11 patients （7.5%） were suspected of Q fever and undergone serological testing for C. burnetii. Six out of 11 suspected cases were diagnosed as Q fever endocarditis. For the remaining 136 BCNE patients, none of them was suspected of Q fever nor underwent relevant testing. Risk factors for Q fever endocarditis were comparable between suspected and unsuspected patients, with the most common risk factors being valvulopathy in both groups. However, significantly more patients had consulted the Infectious Diseases Division and undergone comprehensive diagnostic tests in the suspected group than the unsuspected group （100% vs. 63%, P = 0.03）. Conclusions： Q fever endocarditis is a serious yet treatable condition. Lacking awareness of the disease may prevent BCNE patients from being identified, despite having Q fever risk factors. Increasing awareness and guideline adherence are cruc

关键词： Blood Culture Endocarditis Q Fever