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Highly Soluble Polyimides Containing Di-tert-butylbenzene and Dimethyl Groups with Good Gas Separation Properties and Optical Transparency

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Chinese Journal of Polymer Science 2020年第7期38卷 759-768,I0007页

作者： Chen-Yi Wang Cai-Rong Jiang Bin Yu xiao-yan zhao zhao-Liang Cui Jian Li Qiang Ren Jiangsu Collaborative Innovation Center of Photovoltaic Science and Engineering Jiangsu Key Laboratory of Environmentally Friendly Polymeric MaterialsSchool of Materials Science and EngineeringChangzhou UniversityChangzhou 213164China State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 210009China

A rigid aromatic diamine monomer containing di-tert-butylbenzene and dimethyl groups,3,3'-dimethyl-4,4'-diaminophenyl-3",5"-di-tert-butyltoluene,was successfully synthesized by a simple coupling reaction using 3,5-di-tert-butylbenzaldehyde and o-toluidine as starting materials.A series of novel polyimides(PI 3a-3c)with large pendant groups were prepared with the obtained diamine monomer and three different commercial aromatic dianhydrides(3,3',4,4'-biphenyltetracarboxylic dianhydride,4,4'-oxydiphthalic anhydride,and 4,4'-(hexafluoroisopropylidene)diphthalic anhydride)by one-step high temperature *** prepared polyimides exhibited high solubility and good membrane forming ability:they could be dissolved not only in some high boiling solvents such as DMF,NMP,DMAc,and m-Cresol at room temperature,but also in some low boiling solvents such as CHCl3,CH2Cl2,and *** solubility in most solvents could exceed 10 wt%,and the flexible membranes could be obtained by casting their *** prepared membranes exhibited good gas separation *** permeability coefficients of PI 3c for CO2 and O2 were up to 124.6 and 42.8 barrer,respectively,and the selectivity coefficients for CO2/CH4 and O2/N2 were 14.7 and 3.3,*** membranes had light color and good optical *** optical transmittance at 450 nm wavelength was in the range of 67%-79%,and the cutoff wavelength was in the range of 310-348 *** also had good thermal properties with glass transition temperature(Tg)values in the range of 264-302℃.In addition,these membranes possessed good mechanical properties with tensile strength ranging between 77.8-87.4 MPa,initial modulus ranging between 1.69-1.82 GPa,and elongation at break ranging between 4.8%-6.1%.

关键词： Polyimides Di-tert-butyltoluene Gas separation performance Optical transparency

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Conformation Disturbance of CopC by α-Naphthylamine

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Chemical Research in Chinese Universities 2009年第3期25卷 269-272页

作者： LI Hui-qing ZHENG xiao-yan zhao Ya-qin yanG Bin-sheng Institute of Molecular Science Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education Shanxi University Taiyuan 030006 P. R. China

It is known that urea and guanidine hydrochloride（GuHC1） induce conformational change of proteins in a certain range of molar ratios. In our research, a-naphthylamine（NA） above 10^-4 mol/L at pH 7.0 was discovered to perturb the conformation of CopC, a copper resistant protein with a Greek fl-barrel motif; this was reflected by the greater fluorescence quenching and red-shifted emission peak of CopC. The conformation change of CopC was also verified in acrylamide collision experiment by comparing quenching levels of CopC in the presence or the abscence of NA. Comparison of emission change of CopC-Cu^2＋ with that of apo-CopC showed a consistent result with their denaturation in GuHCl. And decreasing fluorescence polarization of CopC with increasing NA concentration is consistent with a more extend conformation of CopC. Interaction mechanism was also explored.

关键词： α-Naphthylamine(NA) CopC Conformational change

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Wireless esophageal pH capsule for patients with gastroesophageal reflux disease: A multicenter clinical study

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World Journal of Gastroenterology 2014年第40期20卷 14865-14874页

作者： xiao-Jun yang Tian Gan Lei Wang Zhuan Liao xiao-Hong Tao Wei Shen xiao-yan zhao Department of Gastroenterology Xinqiao Hospital Third Military Medical University Department of Gastroenterology Changhai Hospital Second Military Medical University Departmentof Gastroenterology First Affiliated Hospital of Chongqing Medical University Department of Gastroenterology Second Affiliated Hospital of Chongqing Medical University

AIM: To investigate the feasibility and safety of pH capsule to monitor pH in patients with gastroesophageal reflux disease (GERD).

关键词： Wireless pH capsule Feasibility Safety Conventional catheter Gastroesophageal reflux disease

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Hyperoside Suppresses Lipopolysaccharide-induced Inflammation and Apoptosis in Human Umbilical Vein Endothelial Cells

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Current Medical Science 2018年第2期38卷 222-228页

作者： yan-qiang ZHOU Yin-tao zhao xiao-yan zhao Cui LIANG Ya-wei XU Ling LI Yuan LIU Hai-bo yanG Department of Cardiology the First Affiliated Hospital of Zhengzhou University Henan 450052 China

Finding the novel drug from the effective components of traditional Chinese herbal medicine is a hotspot of the modem pharmacological research. Hyperoside （HYP） belongs to flavonoid glycosides, and it has various properties, such as anti-inflammation, anti-spasm, anti-diuretic, antitussive, lowering blood pressure, and lowering cholesterol effects as well as protective effects for the cardiac and cerebral blood vessels. The purpose of this study was to investigate the effects of HYP on inflammatory and apoptotic responses in vascular endothelial cells stimulated by lipopolysaccharide （LPS） and further to identify the possible mechanisms underlying these effects. In our study, human umbilical vein endothelial cells （HUVECs） were stimulated with 1 Bg/mL LPS in the presence or absence of HYP （10, 20 and 50 μmol/L）. Our results indicated that HYP alone exerted no cytotoxicity on HUVECs, while it had an upregulatory effect on the viability of HUVECs induced by LPS in a dose-dependent manner; increased mRNA expression of IL-1β, IL-6, TNFα and iNOS induced by LPS was attenuated after treatment with HYP both in a dose- and time-dependent manner; LPS-induced HUVECs apoptosis and cleaved-caspase 8, 9, 3 were all significantly reduced by HYP. Furthermore, the possible pathway involved in apoptosis and inflammation by HYP was detected, and the results showed that when treated with HYP, LPS-induced mitochondrial membrane instability was significantly inhibited through up-regulation of Bcl-2 and down-regulation of Bax. Furthermore, the expression of TLR4 and the phosphorylation of IκBα and p65 in LPS-treated cells were blocked by HYP. Our results suggested that HYP treatment prevented HUVECs from LPS- induced inflammation and apoptosis responses, which might be mediated by inhibiting TLR4/ NFκB pathway.

关键词： hyperoside lipopolysaccharide inflammation apoptosis human umbilical veinendothelial cells

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Association of changes in waist circumference with cardiovascular disease and all-cause mortality among the elderly Chinese population: a retrospective cohort study

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Journal of Geriatric Cardiology 2021年第3期18卷 185-195页

作者： Xue-Ning ZHANG Hao zhao Zhan SHI Ling YIN xiao-yan zhao Chun-Yu YIN Yong-Li yanG Song-He SHI Department of Epidemiology and Biostatistics College of Public HealthZhengzhou UniversityZhengzhouHenanChina Department of Pharmacy Zhengzhou First People's HospitalZhengzhouHenanChina Department of Neurology Chinese People's Liberation Army General HospitalBeijingChina

BACKGROUND To examine the association of baseline waist circumference(WC)and changes in WC with cardiovascular disease(CVD)and all-cause mortality among elderly *** A total of 30,041 eligible participants were included from a retrospective cohort in *** same questionnaire,anthropometric and laboratory measurements were performed at baseline(2010)and the first follow-up(2013).The percent change in WC between baseline and the first follow-up was calculated to evaluate three years change of *** collected the occurrence of CVD and all-cause death from the first follow-up to December 31,*** cubic splines and Cox proportionalhazards regression models were used to evaluate the relationship between baseline WC/changes in WC and *** The dose-response relationships between baseline WC and CVD mortality were U-or *** low WC group,compared with stable group,the fully adjusted hazard ratio(aHR)for CVD mortality was 1.60(95%CI:1.24−2.06)in WC gain group among *** normal WC group,the CVD mortality risk increased with WC gain(men:aHR=1.86,95%CI:1.36−2.56;women:aHR=1.83,95%CI:1.29−2.58).In moderate-high WC group,the CVD mortality risk increased with WC gain(men:aHR=1.76,95%CI:1.08−2.88;women:aHR=1.46,95%CI:1.04−2.05)and risk decreased with WC loss(men:aHR=0.54,95%CI:0.30−0.98;women:aHR=0.59,95%CI:0.37−0.96).CONCLUSIONS For the elderly population,WC gain may increase CVD mortality risk regardless of baseline WC,whereas WC reduction could decrease the risk only in the moderate-high WC group.

关键词： mortality among elderly

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Formation of Ultrafine Apatite Fibers by Sol-gel/Electrospinning

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Chemical Research in Chinese Universities 2007年第3期23卷 366-369页

作者： DING Ya-mei YUAN xiao-yan zhao Jin GUO Wan-chun WANG Xiu-kui School of Materials Science and Engineering Tianjin University Tianjin 300072 P. R. China

Ultrafine apatite fibers were prepared by electrospinning of sol-gel precursor/poly（ vinyl pyrrolidone）（PVP） solutions followed by subsequent calcination. The as-electrospun and calcinated fibers were observed under a scanning electron microscope and an optical polarizing microscope. Results show that the morphology and the diameter of as-electrospun fibers strongly depend on the viscosity and the surface tension of sol-gel precursor/PVP solutions. After calcination, the smooth as-electrospun fibers shrink and the fiber diameter decreases because of the removal of the polymer. The chemical evolution upon the transformation of the precursor from a gel to the final apatite fibers was investigated by thermogravimetric-differenfial thermal analysis, X-ray diffraction, and Fourier transform infrared spectroscopy. It is thus suggested that the crystalline structure of the calcined fibers is largely influenced by the calcination temperature. After being calcined at 600 ℃, the apatite fibers with a diameter of about 280 nm containing β-tricalcium phosphate were obtained.

关键词： Apatite Ultrafine fiber Sol-gel Electrospinning

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Fabrication of GO-TiO_(2)/(Ca,Y)F_(2):Tm,Yb composites with highefficiency optical driving photocatalytic activity for degradation of organic dyes and bacteriostasis

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Rare Metals 2022年第2期41卷 650-662页

作者： Hua Guo Jun Li Xian-Rui Zou Hong-Shui Wang An Kang Huan Zhou Ming-Jun Li xiao-yan zhao School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300401China Tianjin Juncheng Dentistry Clinic Co.LTD Tianjin 300090China School of Materials Science and Engineering Hebei University of TechnologyTianjin 300000China Institute of Biophysics Hebei University of TechnologyTianjin 300401China

Development of photocatalytic materials able to profit from the whole spectrum of sun for efficient organic pollution removal and bacterial elimination is a fascinating strategy in environmental *** current work,GO-TiO_(2)/(Ca,Y)F_(2):Tm,Yb,a full-spectrum composite photocatalyst,was prepared via hydrothermal processing with TiO_(2)/(Ca,Y)F_(2):Tm,Yb particles deposited on the surface of graphene oxide(GO).The surface properties of GO-TiO_(2)/(Ca,Y)F_(2):Tm,Yb were characterized using various characterization techniques including X-ray diffraction(XRD),scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS)and Brunauer–Emmett–Teller(BET)surface area ***,ultraviolet–visible(UV–Vis)diffuse reflectance spectroscopy,electron spin resonance(ESR)and other methods were used to systematically explore the photocatalytic mechanism of GO enhancement of TiO_(2)/(Ca,Y)F_(2):Tm,*** photocatalytic degradation study,the degradation rate of methyl orange(MO)was improved by 40%when GO was added into the TiO_(2)/(Ca,Y)F_(2):Tm,Yb *** addition,the presence of GO also improves the antibacterial ability of TiO_(2)/(Ca,Y)F_(2):Tm,Yb against Escherichia coli and Staphylococcus *** results reveal high efficacy of GOTiO_(2)/(Ca,Y)F_(2):Tm,Yb under full spectrum light irradiation,in which(Ca,Y)F2:Tm,Yb and TiO2 can improve its utilization of full spectrum sunlight,and GO can enhance adsorption ability of dye and electron–hole pair differentiation ability of TiO_(2)/(Ca,Y)F_(2):Tm,Yb.

关键词： Photocatalysis Graphene oxide Upconversion Adsorption

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Association of level of leisure-time physical activity with risks of all-cause mortality and cardiovascular disease in an elderly Chinese population: a prospective cohort study

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Journal of Geriatric Cardiology 2020年第10期17卷 628-637页

作者： Hao zhao Xue-Ning ZHANG Zhan SHI Ling YIN Wen-Li ZHANG Kun HE Xue-Qi HU xiao-yan zhao Song-He SHI Department of Epidemiology and Biostatistics College of Public HealthZhengzhou UniversityHenanChina Department of Pharmacy Zhengzhou First People’s HospitalZhengzhouHenanChina Department of Neurology Chinese PLA General HospitalBeijingChina

Background Implementing the current guidelines for leisure-time physical activity(LTPA)provides significant health benefits,especially for middle-aged adults,but it is unclear whether LTPA also translates into cardiovascular health benefits among elderly ***,we aimed to assess the association of LTPA with the risks of cardiovascular disease(CVD),including coronary heart disease(CHD)and stroke,and all-cause mortality in an elderly *** In this prospective cohort study,32,942 participants aged 60 years or older who participated in a health check-up programme in China between 2010 and 2018 were *** evaluated the morbidity and mortality risks through the Cox regression model,competing risk model and restricted cubic spline *** During a median of 6.84 years of follow-up,there were 6,857 elderly people with incident CVD;a total of 6,324 deaths occurred due to all causes and 2,060 deaths occurred due to *** with the inactive group,reductions in CVD morbidity and mortality were observed,with hazard ratios(HRs)of 0.89(95%CI:0.83–0.96)and 0.81(95%CI:0.71–0.92)in the insufficiently active group,0.86(95%CI:0.80–0.92)and 0.79(95%CI:0.69–0.90)in the sufficiently active group,and 0.79(95%CI:0.70–0.89)and 0.58(95%CI:0.45–0.76)in the highly active group,respectively;but no significant reductions were observed in the very highly active group,with HRs of 0.87(95%CI:0.71–1.06)and 0.99(95%CI:0.70–1.40),*** with the inactive group,reductions in all-cause mortality were also observed,with a HR of 0.90(95%CI:0.84–0.97)in the insufficiently active group,0.82(95%CI:0.77–0.89)in the sufficiently active group,0.77(95%CI:0.67–0.87)in the highly active group,and 0.80(95%CI:0.64–0.98)in the very highly active group.A restricted cubic spline diagram showed that there was an L-shaped association between LTPA and the risk of all-cause mortality but a U-shaped or reverse J-shaped relationship between LTPA and the risk of CVD morb

关键词： Cardiovascular disease Chronic coronary disease Leisure-time physical activity Stroke

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Six million Q factor micro fused silica shell resonator with teeth-like tines released by femtosecond laser-assisted chemical etching

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Science China(Technological Sciences) 2024年第6期67卷 1923-1932页

作者： zhao Tao SHI yan LU Kun XI Xiang WU XueZhong xiao DingBang College of Intelligence Science and Engineering National University of Defense TechnologyChangsha410073China

The quality factor(Q factor)is a crucial performance parameter for *** this paper,a novel release method for highquality micro fused silica shell resonators with teeth-like tines with good surface morphology is *** method is based on femtosecond laser-assisted chemical ***,the optimal energy range of femtosecond laser modification is obtained through mechanism ***,the optimal parameters for a straight line and arc pattern are determined by optimizing the average output power,processing speed,and processing *** results demonstrate why edge breakage in rounded corners is easy under different ***,according to these conclusions,the processing is performed on a micro fused silica shell resonator with a Q factor exceeding 6 *** addition,subsurface damage is rare throughout the fabrication process,and the surface roughness of the released cross section reaches the nanometer *** improved Q factor helps suppress mechanical thermal noise and reduce zero bias and zero bias drift,constituting the primary method for enhancing the performance of the resonant gyroscope.

关键词： micro hemispherical resonator fused silica laser-assisted chemical etching quality factor

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Elastoplastical analysis on cylinder of different moduli in tension and compression

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Journal of Coal Science & Engineering(China) 2009年第1期15卷 66-71页

作者： WANG Wei-ming ZHANG xiao-yan yanG zhao WANG Qing-biao College of Civil Engineering and Architecture Shangdong University of Science and Technology Qingdao 266510 China

The constitutive equation was deduced. The results were obtained from theelastic and elastoplastical analysis of the cylinder sample applied with different ratios ofload on both the inner and outer sides and different moduli ratio. The factors affecting thedevelopment of the plastic field of the cylinder with finite radius were shown. The resultsshow that the different moduli ratio is the most important factor in the development of theplastic zone. The slight fluctuation of the ratio will bring multiplied increment of the displacement, which may result in the final destruction of the engineering material.

关键词： cylinder different moduli plastic zone elastoplastical analysis

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