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Journal of Materials Science & Technology 2013年第1期29卷 22-28页

作者： Jilin xu fu Liu Junming Luo Liancheng Zhao School of Materials Science and Engineering Nanchang Hangkong University School of Materials Science and Engineering Harbin Institute of Technology

Plasma electrolytic oxidation （PEO） coatings, formed under various anodic voltages （320-440 V） on biomedical NiTi alloy, are mainly composed of γ-AI203 crystal phase. The evolution of discharging sparks during the PEO process under different anodic voltages was observed. The surface and cross-sectional morphologies, composition, bonding strength, wear resistance and corrosion resistance of the coatings were investigated by scanning electron microscopy （SEM）, thin-film X-ray diffraction （TF-XRD）, energy dispersive X-ray spectrometry （EDS）, surface roughness, direct pull-off test, ball-on-disk friction and wear test and potentiodynamic polarization test, respectively. The results showed that the evolution of discharging sparks during the PEO process directly influenced the microstructure of the PEO coatings and further influences the properties. When the anodic voltage increased from 320 V to 400 V, the corrosion resistance and wear resistance of the coatings slowly increased, and all the bonding strength was higher than 60 MPa; further increasing the anodic voltages, especially up to 440 V, although the thickness and γ-AI203 crystallinity of the coatings further increased, the microstructure and properties of the coatings were obviously deteriorated.

关键词： Plasma electrolytic oxidation Biomedical NiTi alloy AI203 coating Anodic voltage

Simulation and prediction of multi-scenario evolution of ecological space based on FLUS model: A case study of the Yangtze River Economic Belt, China

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Journal of Geographical Sciences 2023年第2期33卷 373-391页

作者： LIU Xiaoqiong WANG xu CHEN Kunlun LI dan School of Environmental Studies China University of GeosciencesWuhan 430074China China Institute of Mountaineering and Outdoor Sports Wuhan 430074China School of Geography and Information Engineering China University of GeosciencesWuhan 430074China School of Physical Education China University of GeosciencesWuhan 430074China Institute of Geography and Tourism Guangdong University of Finance&EconomicsGuangzhou 510320China

Building the Yangtze River Economic Belt(YREB)is one of China’s three national development policies in the new *** ecological environment of the Yangtze River Economic Belt must be protected not only for regional economic development but also for regional ecological security and ecological progress in this *** paper takes the ecological space of the Yangtze River Economic Belt as the research object,based on land use data in 2010 and 2015,and uses the FLUS model to simulate and predict the ecological space of the research area in *** variation of the research area’s ecological space area and its four sub-zones has remarkable stability under diverse *** the production space priority scenarios(S1)and living space priority scenarios(S2)saw a fall in ecological space area,with the former experiencing the highest reduction(a total reduction of 25,212 km^(2)).Under the ecological space priority scenarios(S3)and comprehensive space optimization scenario(S4),the ecological space area increased,and the ecological space area expanded even more under the former scenario(a total growth of 23,648 km^(2)).In Yunnan-Guizhou,the ecological space is relatively stable,with minimal signs of *** Sichuan-Chongqing,the Sichuan Basin,Zoige Grassland,and Longmen Mountains were significant regions of area changes in ecological *** the middle reaches of the Yangtze River,the ecological space changes mainly occur in the Wuyi Mountains,Mufu Mountains,and Dabie Mountains,as well as the surrounding waters of Dongting *** Yangtze River Delta’s changes were mainly observed in the eastern Dabie Mountains and Jianghuai Hills.

关键词： ecological space multi-scenario simulation prediction FLUS model Yangtze River Economic Belt extensive protection of the Yangtze River

Effect of Berberine on Activation of TLR4-NFκB Signaling Pathway and NLRP3 Inflammasome in Patients with Gout

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Chinese Journal of Integrative Medicine 2023年第1期29卷 10-18页

作者： danG Wan-tai xu dan ZHOU Jing-guo Chengdu Medical College and the First Affiliated Hospital of Chengdu Medical College Chengdu610500China

Objective:To determine the effects of berberine(BBR) on the activation of toll-like receptor 4(TLR4),nuclear factor(NF) κB(NF-κB) signaling and NLRP3 inflammasome in patients with ***:Peripheral blood mononuclear cells(PBMCs) were obtained from 24 acute(AP) and 41 non-acute(NAP) phases of primary gout patients,respectively,as well as 30 healthy controls(HC).TLR4,NF-κB(p65),NLRP3,apoptosis-associated specklike protein containing a CARD(PYCARD),cysteinyl aspartate specific proteinase-1(CASP1),and interleukin-1 β(IL-1 β) mRNA expression levels in PBMCs were measured by quantitative reverse transcriptase polymerase chain *** protein levels of TLR4,myeloid differentiation factor 88(MyD88),NF-κB(p50/65),inhibitor of kappa B kinase α/β(IKKα/β),NF-κB inhibitor α(IKB α),phospho-IKKα/β(p-IKKα/β),NLRP3,PYCARD,and CASP1were monitored by Western *** IL-1 β protein level was measured using enzyme-linked immunosorbent assay(ELISA).In addition,PBMCs from HC and macrophages derived from a spontaneously immortalized monocyte-like cell line(THP-1) were stimulated using monosodium urate(MSU,100 μ g/mL),0.1% dimethyl sulfoxide,25 μmol/L BBR,and 10,25,and 50 μmol/L BBR+100 μg/mL MSU for different time *** protein levels of IL-1β and IL-18 in cell culture supernatants was measured by ELISA,and the protein expressions of TLR4,MyD88,NF-κB(p50/p65),IKK α/β,IκBα,p-IKKα/β,NLRP3, PYCARD,and CASP1 in macrophages were analyzed by Western ***:(1) TLR4,NF-κB(p65),PYCARD,CASP1,and IL-1β mRNA levels in PBMCs were significantly higher in the AP group than in the HC group(P<0.05).The NLRP3 mRNA expression levels in PBMCs were found to be significantly lower in the AP and NAP groups than in the HC group(P<0.05,P<0.01).(2) The protein levels of TLR4,IKKβ,MyD88,NF-κB,p-IKKα/β,PYCARD,and CASP1 in PBMCs were significantly higher,and those of IκBα,IKKα,and NLRP3 were found to be significantly lower in the AP group than in the HC group(P<0.05 or P<0.01).(3) Th

关键词： berberine gout TLR4-NF-κB NLRP3 inflammasome monosodium urate

Enhanced Wear Resistance of Ni/h-BN Composites with Graphene Addition Produced by Spark Plasma Sintering

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Acta Metallurgica Sinica(English Letters) 2019年第7期32卷 876-886页

作者： Jiao xu dan-Qing Yi Qiang Cui Bin Wang School of Material Science and Engineering Central South University Changsha 410083 China Light Alloy Research Institute Central South University Changsha 410083 China

Ni-based self-lubricating composites containing a fixed amount of hexagonal boron nitride (h-BN)(5 wt%) and different amounts of graphene (0-1.5 wt%) were prepared by ultrasonic dispersion, high-energy ball milling, and spark plasma sintering. The effects of the graphene content on the physical, mechanical, and wear properties of the Ni/h-BN composites were evaluated. These properties were first enhanced with increasing graphene content, reaching optimal behavior for a graphene content of 1 wt%, and then degraded with further graphene addition. Compared to the pure Ni/h-BN composite, the relative density, hardness, and bending strength of the composite with 1 wt% graphene increased by 2.7%, 7.4%, and 6.3%, respectively, while the friction coefficient decreased by 56% to 0.31, and a reduction in wear rate by a factor of 5-15 was observed. The mechanism for improving the wear properties of the composite with added graphene was due to the formation of a graphene lubricating film on the worn surface, which increased the load bearing capacity of the surface and enhanced lubrication during wear.

关键词： Graphene h-BN Wear Ni matrix composites

EPIDEMIC SPREAD ON ONE-WAY CIRCULAR-COUPLED NETWORKS

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Acta Mathematica Scientia 2019年第6期39卷 1713-1732页

作者： Zhongpu xu Xinchu fu Department of Mathematics Shanghai UniversityShanghai 200444China

Real epidemic spreading networks are often composed of several kinds of complex networks interconnected with each other, such as Lyme disease, and the interrelated networks may have different topologies and epidemic dynamics. Moreover, most human infectious diseases are derived from animals, and zoonotic infections always spread on directed interconnected networks. So, in this article, we consider the epidemic dynamics of zoonotic infections on a unidirectional circular-coupled network. Here, we construct two unidirectional three-layer circular interactive networks, one model has direct contact between interactive networks, the other model describes diseases transmitted through vectors between interactive networks, which are established by introducing the heterogeneous mean-field approach method. Then we obtain the basic reproduction numbers and stability of equilibria of the two models. Through mathematical analysis and numerical simulations, it is found that basic reproduction numbers of the models depend on the infection rates, infection periods, average degrees, and degree ratios. Numerical simulations illustrate and expand these theoretical results very well.

关键词： epidemic dynamics coupled network Lyme disease infective medium basic reproduction number

SIMULATIONS OF THE THREE-DIMENSIONAL TOTAL DISSOLVED GAS SATURATION DOWNSTREAM OF SPILLWAYS UNDER UNSTEADY CONDITIONS

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Journal of Hydrodynamics 2010年第4期22卷 598-604页

作者： fu Xiao-li LI dan ZHANG Xiao-feng State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China

Dams are often operated in a way to discharge over the spillways,which would cause a high dissolved concentration of air and be harmful to *** bubble transfer and the water surface transfer play an important role in affecting the concentration of the Total Dissolved Gas（TDG）.Based on recent numerical simulations of the total dissolved gas saturation,in this article,a two-phase TDG transport equation is adopted to develop an unsteady three-dimensional（3-D） two-phase flow Computational Fluid Dynamics（CFD） model,including a number of parameters such as water depth,pressure and air volume *** model is used to predict the hydrodynamics and the TDG distribution under unsteady discharge *** agreement between measured and numerical results is obtained for a case study.

关键词： gas supersaturation anisotropic two-phase flow

Effect of an Airbag-selective Portal Vein Blood Arrester on the Liver after Hepatectomy:A New Technique for Selective Clamping of the Portal Vein

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Current Medical Science 2024年第2期44卷 380-390页

作者： Ce-xiong fu Xiao-ri QIN Jin-song CHEN Jie ZHONG Yu-xu XIE Bi-dan LI Qing-qing fu Fang LI Jin-fang ZHENG Department of Hepatobiliary and Pancreatic Surgery Hainan General HospitalHainan Affiliated Hospital of Hainan Medical UniversityHaikou 570311China University of South China Hengyang 421001China Department of Gastroenterology Gastroenterology Endoscopy CenterHainan General HospitalHainan Affiliated Hospital of Hainan Medical UniversityHaikou 57031lChina Center of Clinical Laboratory Hainan General HospitalHainan Affiliated Hospital of Hainan Medical UniversityHaikou 570311China Department of Radiology Hainan General HospitalHainan Affiliated Hospital of Hainan Medical UniversityHaikou 570311China

Objective:A novel technique was explored using an airbag-selective portal vein blood arrester that circumvents the need for an intraoperative assessment of anatomical variations in patients with complex intrahepatic space-occupying ***:Rabbits undergoing hepatectomy were randomly assigned to 4 groups:intermittent portal triad clamping(PTC),intermittent portal vein clamping(PVC),intermittent portal vein blocker with an airbag-selective portal vein blood arrester(APC),and without portal blood occlusion(control).Hepatic ischemia and reperfusion injury were assessed by measuring the 7-day survival rate,blood loss,liver function,hepatic pathology,hepatic inflammatory cytokine infiltration,hepatic malondialdehyde levels,and proliferating cell nuclear antigen ***:Liver damage was substantially reduced in the APC and PVC *** APC animals exhibited transaminase levels similar to or less oxidative stress damage and inflammatory hepatocellular injury compared to those exhibited by the PVC *** was significantly higher in the control group than in the other *** APC group had less bleeding than the PVC group because of the avoidance of portal vein skeletonization during ***,more operative time was saved in the APC group than in the PVC ***,the total 7-day survival rate in the APC group was higher than that in the PTC ***:Airbag-selective portal vein blood arresters may help protect against hepatic ischemia and reperfusion injury in rabbits undergoing partial *** technique may also help prevent liver damage in patients requiring hepatectomy.

关键词： hepatectomy portal vein hepatic damage selective clamping

Mechanical and corrosion fatigue behaviors of gradient structured 7B50-T7751 aluminum alloy processed via ultrasonic surface rolling

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Journal of Materials Science & Technology 2020年第5期40卷 88-98页

作者： Xingchen xu Daoxin Liu Xiaohua Zhang Chengsong Liu dan Liu Corrosion and Protection Research Laboratory Northwestern Polytechnical UniversityXi’an 710072China

In this work,ultrasonic surface rolling process(USRP)was utilized to produce a gradient structured layer on 7 B50-T7751 aluminum alloy,and the mechanical properties and corrosion fatigue behavior of treated samples were *** results reveal that underwent USRP,a 425~m thick gradient structure and a 700~m deep compressive residual stress field are created,aluminum grain size become fine(~67 nm),and the corrosion rate of treated surface reduces by 60.08%owing to the combined effect of compressive residual stress and surface *** corrosion fatigue strength is enhanced to 117%of that of 7 B50 Al alloys by means of USRP due to the introduced compressive residual stress,which is considered as the major favorable factor in suppressing the initiation and early propagation of corrosion fatigue ***,the gradient structure is an important factor in providing a significant synergistic contribution to the improvement of corrosion fatigue performance.

关键词： Aluminum alloy Mechanical properties Corrosion fatigue behavior Gradient structure Compressive residual stress Ultrasonic surface rolling process

Numerical simulation and cause analysis of persistent summer drought during the 1920s in eastern China

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Science China Earth Sciences 2022年第5期65卷 966-982页

作者： Meng LUO Jinming FENG Zhongfeng xu Jun WANG Li dan Yunnan Climate Center Kunming 650034China Key Lab of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

In the late 1920’s,a mega-drought in China resulted in widespread crop failure and *** evidence suggests that this drought belonged to a dry period ranging from approximately 1922 to *** understand the characteristics and the cause of this persistent drought period,we combined various data,including observations,tree ring proxy data,reanalysis data,simulation results of the Fifth Phase of the Coupled Model Intercomparison Project and numerical downscaling *** results show that during 1922-1932,most regions in eastern China suffered from a persistent drought that lasted for six years,and the maximum negative precipitation anomaly reached−1.5 times the standard *** its spatial coverage,duration,and strength,the 1920s drought was unique for the 20th *** 1920s drought was primarily caused by internal *** easterlies in lower latitudes,strong monsoon circulation,and abnormally high geopotential heights at middle and upper levels were responsible for the 1920s drought conditions in eastern China;these drought conditions could be further attributed to the joint impact of the Atlantic Multidecadal Oscillation,Pacific Decadal Oscillation and Indian Ocean Basin Mode.

关键词： Drought 1920s Eastern China East Asia Summer Monsoon Regional Climate Model Atlantic Multidecadal Oscillation Pacific Decadal Oscillation Indian Ocean Basin Mode

Tetrabenzotriazacorrole and its derivatives as undopea hole transporting materials for perovskite solar cells:Synthesis,device fabrication,and device performance

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Journal of Energy Chemistry 2020年第4期29卷 139-147页

作者： Xian-fu Zhang Chang Liu Jianchang Wu Baomin xu Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055GuangdongChina Institute of Applied Photochemistry Hebei Normal University of Science and TechnologyQinhuangdao 066004HebeiChina Shenzhen Engineering Research and Development Center for Flexible Solar Cells Southern University of Science and TechnologyShenzhen 518055GuangdongChina

Phosphorous tetrabenzotriazacorrole(TBC)and its two soluble derivatives(TBC-1 and TBC-2)were synthesized and used for the first time as undoped hole transporting materials(HTMs)in MAPbI3 perovskite solar cells(PSCs).Their performance in PSCs was measured and compared with that of SpiroOMeTAD and phthalocyanine *** fundamental properties related to HTMs are also *** novel HTMs are easily prepared,cost-effective,and solution *** materials exhibited much higher hole transport mobility and broader light absorption than pristine Spiro-OMeTAD and phthalocyanine *** can work efficiently in the absence of any dopant for devices composed of FTO/cp-TiO2/mp-TiO2/MAPbI3/HTM/*** undoped mesoscopic solar cell devices based on TBC exhibited a promising power conversion efficiency(PCE)of up to 16.2%(measured at 100 mWcm2 illumination,AM 1.5 G),together with good long-term stability under ambient *** PCE of 16.2%observed using TBC is remarkably higher than the 11.2%observed using undoped Spiro-OMeTAD and also much better than the 8.70%observed using its phthalocyanine *** to substitution effects,α-substituted TBC-1 was found to be a better HTM thanβ-substituted TBC-2(PCE 11.4%)and unsubstituted TBC-3(PCE 6.81%)under the same *** results provide the basis for further exploiting TBC compounds as a new type of low-cost and effective HTM for PSCs.

关键词： Perovskite solar cell Hole transporting material Tetrabenzotriazacorrole Phthalocyanine