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Spatial Spillover and the Factors Influencing Public Service Supply in Sichuan Province, China

Journal of Mountain Science 2014年第5期11卷 1356-1371页

作者： song xue-qian DENG Wei LIU Ying Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu University of Information Technology University of Chinese Academy of Sciences

This article examines the spatial characteristics of public service supply and the factors influencing such supply in cities of Sichuan Province, China using spatial-autocorrelation and spatial econometric models with statistical data in 2012. The results demonstrate that expenditures on different types of public services present different spatial autocorrelation patterns. Although the spatial differences in basic public service expenditures are relatively small, a clear fan-shaped spillover to the east can be seen in Chengdu City. Chengdu also shows high clustering of advanced public service expenditures, being a typical core-periphery pattern. Post-earthquake reconstruction expenditures are clustered in the "5.12 Wenchuan earthquake" region and spill over toward cities to the east. The efficiency of public services in the mountainous areas in western Sichuan is low and exhibits a pattern of low-low spatial autocorrelation. The efficiency of public service supply is affected by economic, social, political and geographical factors. Based on the results of this analysis, we recommend a supply strategy that incorporates different types of public services and a specialized public service supply strategy for mountainous areas. Overall public service efficiency should be enhanced by focusing on narrowing the gap in farmers' income among regions and accelerating urbanization. Decision-makers should consider moresupportive policies with regard to providing basic public services in mountainous areas to ensure an equalized supply of basic public services. To enhance the efficiency of advanced public service supply, additional growth pole should be encouraged and incentivized; however, investments are required to drive the development of the peripheral regions through regional economic integration. Both software and hardware types of infrastructure are required to supply services efficiently during post-disaster reconstruction.

关键词： Public services Spatial Spillover Spatial Econometric Model Relief Degree of Land Surface China

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Relief Degree of Land Surface and Population Distribution of Mountainous Areas in China

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Journal of Mountain Science 2015年第2期12卷 518-532页

作者： LIU Ying DENG Wei song xue-qian Institute of Mountain Hazards and Environment Chinese Academy of Science University of Chinese Academy of Science Chengdu University of Information Technology

Evaluation on the population pressure in the mountainous areas is a necessary condition for the protection and good governance. The evaluation depends on accurate population density assessment. Traditional methods used to calculate population density often adopt the administrative region as a scale for statistical analysis. These methods did not consider the effects of the relief degree of land surface(RDLS) on the population distribution. Therefore they cannot accurately reflect the degree of population aggregation, especially in mountainous areas. To explore this issue further, we took the mountainous areas of China as the research area. China has A total area of 666 km2 can be classified as mountainous area,accounting for 69.4% of the country's total landmass. The data used in this research included the digital elevation model(DEM) of China at a scale of 1:1,000,000, National population density raster data, the DEM and the national population density raster data. First, we determined the relief degree of land surface(RDLS). Next, we conducted a correlation analysis between the population distribution and the RDLS using the Statistical Package for Social Science(SPSS). Based on the correlation analysis results and population distribution, this new method was used to revise the provincial population density of themountainous areas. The revised results were used to determine the population pressure of different mountainous areas. Overall, the following results were obtained:(1) The RDLS was low in most mountainous areas(with a value between 0 and 3.5) and exhibited a spatial pattern that followed the physiognomy of China;(2) The relationship between the RDLS and population density were logarithmic, with an R2 value up to 0.798(p<0.05), and the correlation decreased from east to west;(3) The difference between the revised population density(RPD) and the traditional population density(PD) was larger in the southeastern region of China than in the northwestern region;(

关键词： Land surface Relief degree Population density Population pressure Population distribution Mountain China

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Experimental and numerical investigation of the impacts of rotor tip-rake on excitation forces of pump-jet propulsors

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Journal of Hydrodynamics 2024年第1期36卷 142-157页

作者： xue-qin Ji Xiao-song Zhang Chen-jun Yang Xiao-qian Dong State Key Laboratory of Ocean Engineering Marine Numerical Experiment CentreSchool of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China CSSC Shanghai Marine Energy Saving Technology Co. Ltd.Shanghai200011China China Ship Scientific Research Center Shanghai Branch Shanghai200011China

The tip-clearance flow in a pump-jet propulsor exerts great impacts on the fluctuating pressures and resultant unsteady forces,which are important sources of structural vibrations and radiated noise *** blade geometry close to the tip is an important factor determining the vortex strength in the tip-clearance *** the open-water condition,the effects of raking the rotor tips on the duct-surface fluctuating pressures and the resultant unsteady forces acting on different components of the propulsor are investigated via physical model experiments and the numerical solution of Reynolds-averaged Navier-Stokes(RANS)equations coupled with the SST k-ωturbulence *** measured and simulated results of hydrodynamic pressures are consistent to each other,and the simulated flows help better understand why the fluctuating pressures change with the tip *** strong fluctuations of duct-surface pressures are caused by intensive tip separation *** duct-surface pressure fluctuations are effectively reduced by using the rake distribution near the tip towards blade back side and,for the combination of the five-bladed rotor and the seven-bladed stator,the resultant unsteady horizontal(and vertical)forces acting on the duct and stator are also reduced;while increasing rake leads to negative effect on pressure fluctuations and unsteady horizontal(and vertical)forces acting on all the components of the propulsor.

关键词： Pump-jet tip-clearance tip-rake fluctuating pressures excitation forces

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Mechanical property of cylindrical sandwich shell with gradient core of entangled wire mesh

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Defence Technology（防务技术） 2024年第1期31卷 510-522页

作者： Xin xue Chao Zheng Fu-qiang Lai xue-qian Wu Institute of Metal-rubber&Vibration Noise School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou350116China Fujian Metallurgical Industry Design Institute Fuzhou350116China

To explore the wide-frequency damping and vibration-attenuation performances in the application of aerospace components,the cylindrical sandwich shell structure with a gradient core of entangled wire mesh was proposed in this ***,the gradient cores of entangled wire mesh in the axial and radial directions were prepared by using an in-house Numerical Control weaving machine,and the metallurgical connection between skin sheets and the gradient core was performed using vacuum ***,to investigate the mechanical properties of cylindrical sandwich shells with axial or radial gradient cores,quasi-static and dynamic mechanical experiments were carried *** primary evaluations of mechanical properties include secant stiffness,natural frequency,Specific Energy Absorption(SEA),vibration acceleration level,and so *** results suggest that the vibration-attenuation performance of the sandwich shell is remarkable when the high-density core layer is at the end of the shell or abuts the inner *** axial gradient material has almost no influence on the vibration frequencies of the shell,whereas the vibration frequencies increase dramatically when the high-density core layer approaches the ***,compared to the conventional sandwich shells,the proposed functional grading cylindrical sandwich shell exhibits more potential in mass reduction,stiffness designing,and energy dissipation.

关键词： Entangled wire mesh Gradient cylindrical sandwich shell Vacuum brazing Secant stiffness Damping

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Emerging perovskite materials for supercapacitors:Structure,synthesis,modification,advanced characterization,theoretical calculation and electrochemical performance

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Journal of Energy Chemistry 2024年第2期89卷 41-70,I0003页

作者： Yuehua qian Qingqing Ruan Mengda xue Lingyun Chen Department of Applied Chemistry School of Chemistry and Chemical EngineeringChongqing UniversityChongqing 401331China

As a new generation electrode materials for energy storage,perovskites have attracted wide attention because of their unique crystal structure,reversible active sites,rich oxygen vacancies,and good *** this review,the design and engineering progress of perovskite materials for supercapacitors(SCs)in recent years is ***,the review will focus on four types of perovskites,perovskite oxides,halide perovskites,fluoride perovskites,and multi-perovskites,within the context of their intrinsic structure and corresponding electrochemical performance.A series of experimental variables,such as synthesis,crystal structure,and electrochemical reaction mechanism,will be carefully analyzed by combining various advanced characterization techniques and theoretical *** applications of these materials as electrodes are then featured for various ***,we look forward to the prospects and challenges of perovskite-type SCs electrodes,as well as the future research direction.

关键词： Perovskite Modification engineering Oxygen vacancy Theoretical calculation methodology Supercapacitor

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Rhodium-Catalyzed N-Arylation Addition of Arylboronic Acids to Ketimines

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Chinese Journal of Chemistry 2024年第18期42卷 2243-2248页

作者： xue-Wei qian Xing-Wen Sun Department of Chemistry Fudan University220 Handan RoadShanghai 200433China

Herein,we report rhodium catalyzed N-arylation via addition of arylboronic acids to electron-deficientα-iminoesters which can be prepared in high efficiency by using easily accessible B-carbonyl *** reaction is highly regiospecific to achieve the N-aryl addition efficiently with up to 99%yield under mild *** corresponding product can be further efficiently converted into indoles andaseries of other important building blocks.

关键词： Rhodium catalyzed N-Arylation addition Amines Umpolung Indole C-C coupling

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Mechanical performance of 22SiMn2TiB steel welded with lowtransformation- temperature filler wire and stainless steel filler wire

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Journal of Iron and Steel Research International 2024年第4期31卷 967-981页

作者： Zi-dong Lin Kai-jie song Zhen Sun Zi-qian Zhu xue-feng Zhao Constantinos Goulas Wei Ya Xing-hua Yu School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China Department of Design Production and Management Faculty of Engineering Technology.University of TwenteEnschede 7500 AETheNetherlands Rotterdam Additive Manufacture Fieldlab(RAMLAB) Rotterdam 3089 JWTheNetherlands

TX-80 low-transformation-temperature(LTT)welding wire was used to replace the traditional ER 307Si welding wire to realize the connection of 22SiMn2TiB armor steel in manual overlay *** previously existing issues,such as welding cracks,large welding deformation,and severe welding residual stress,were solved to ensure good strength and ductility *** particular,with the same welding conditions,TX-80 LTT wire eliminates welding *** reduces the welding deformation no matter the base pretreatment of pre-setting angle or no pre-setting *** comparison,it was found that the microstructure at the TX-80 weld is mainly composed of martensite and a small amount of retained *** contrast,the microstructure of the ER 307Si weld consists of a large amount of austenite and a small amount of skeleton-like *** variation trend of residual stress and microhardness from the weld to the base were investigated and compared with the mechanical properties of base *** TX-80 and the ER 307Si tensile samples elongation is 6.76%and 6.01%,while the ultimate tensile strengths are 877 and 667 MPa,*** average impact toughness at room temperature of the ER 307Si weld is 143.9 J/cm^(2),much higher than that of the TX-80 weld,which is only 36.7 J/cm^(2).The relationship between impact and tensile properties with microstructure species and distribution was *** addition,the fracture surface of the tensile and the impact samples was observed and *** dimples,fewer pores,larger radiation zone,and shear lips of TX-80 samples indicate better tensile ductility and worse impact toughness than those of ER 307Si weld.

关键词： Low-transformation-temperature material 22SiMn2TiB steel Welding deformation Residual stress Martensitic transformation Mechanical property

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Perspective for OER electrocatalysts:Lattice engineering of clay-like frameworks with near-surface cluster active sites

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Science China(Technological Sciences) 2024年第1期67卷 330-334页

作者： ZHANG DanTong qian BinBin xue DongFeng Multiscale Crystal Materials Research Center Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Near-surface cluster active centers(NSCAC)are pivotal functional units in the catalysis of oxygen evolution reaction(OER),which exceeds the limitations imposed by the diverse coordination environments experienced in atomic and molecular active centers,thereby serving as an exceptional medium for exploring the dynamic catalytic processes of metal active sites[1,2].In the OER,the NSCAC primarily consist of the catalytic site and the first neighboring coordinating *** investigation of NSCAC surpasses the exclusive reliance on the electron state regulation mechanism at the atomic level.

关键词： cluster centers exceptional

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Emerging two-dimensional Mo-based materials for rechargeable metal-ion batteries:Advances and perspectives

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Journal of Energy Chemistry 2024年第2期89卷 487-518,I0012页

作者： Qingqing Ruan Yuehua qian Mengda xue Lingyun Chen Qichun Zhang Department of Applied Chemistry School of Chemistry and Chemical EngineeringChongqing UniversityChongqing 401331China Department of Materials Science and Engineering City University of Hong Kong999077Hong KongChina

With the rapid development of rechargeable metal-ion batteries(MIBs)with safety,stability and high energy density,significant efforts have been devoted to exploring high-performance electrode *** recent years,two-dimensional(2D)molybdenum-based(Mo-based)materials have drawn considerable attention due to their exceptional characteristics,including low cost,unique crystal structure,high theoretical capacity and controllable chemical ***,like other transition metal compounds,Mo-based materials are facing thorny challenges to overcome,such as slow electron/ion transfer kinetics and substantial volume changes during the charge and discharge *** this review,we summarize the recent progress in developing emerging 2D Mo-based electrode materials for MIBs,encompassing oxides,sulfides,selenides,*** introducing the crystal structure and common synthesis methods,this review sheds light on the charge storage mechanism of several 2D Mo-based materials by various advanced characterization *** latest achievements in utilizing 2D Mo-based materials as electrode materials for various MIBs(including lithium-ion batteries(LIBs),sodium-ion batteries(SIBs)and zinc-ion batteries(ZIBs))are discussed in ***,the modulation strategies for enhancing the electrochemical performance of 2D Mo-based materials are highlighted,focusing on heteroatom doping,vacancies creation,composite coupling engineering and nanostructure ***,we present the existing challenges and future research directions for 2D Mo-based materials to realize high-performance energy storage systems.

关键词： Molybdenum-based materials Two-dimensional materials Lithium-ion batteries Sodium-ion batteries Zinc-ion batteries

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Electroacupuncture Promotes Angiogenesis in Mice with Cerebral Ischemia by Inhibiting miR-7

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Chinese Journal of Integrative Medicine 2024年第6期30卷 543-550页

作者： YU qian SHU Shi JU Xin-yao PENG Wei REN xue-qi SI Shu-han song Shi-zhen XIE xue-yun FANG Bang-jiang ZHOU Shuang School of Acupuncture-Moxibustion and Tuina Shanghai University of Traditional Chinese MedicineShanghai201203China College of Basic Medicine Shanghai University of Traditional Chinese MedicineShanghai201203China Department of Emergency Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai200032China

Objective To observe the angiogenesis effect of electroacupuncture(EA)at Shuigou acupoint(GV 26)in the treatment of cerebral ischemia,and explore the value of miRNA-7(miR-7)in *** First,48 mice were randomly divided into sham operation,middle cerebral artery occlusion(MCAO)model,and EA treatment *** 9 mice were divided into carrier control group,miR-7 knockout group and miR-7 overexpression group(n=3 each group).Finally,20 mice were divided into model and carrier control group,model and miR-7 knockout group,EA treatment and carrier control group and EA treatment and miR-7 overexpression group,with 3–6 mice in each *** MCAO model was established in the MCAO and EA *** deficit score and 2,3,5-triphenyltetrazolium chloride(TTC)staining were used to evaluate the severity of cerebral ***-eosin staining was used to describe basic pathological *** was used to quantify cerebral microvessel ***-time PCR and Western blot were used to detect the expression of miR-7 and its downstream target genes Krüppel-like factor 4/vascular endothelial growth factor(KLF4/VEGF)and angiopoietin-2(ANG-2)in the ischemic cerebral *** After EA,neurological deficit scores and infarction volumes decreased,and the density of cerebral microvessels *** the MCAO group,miR-7 expression was higher than that in the sham group(P<0.01).After EA at GV 26,miR-7 expression decreased(P<0.01)and the expression of downstream target genes KLF4/VEGF and ANG-2 increased as compared with the MCAO group(P<0.01).After EA combined with overexpression of miR-7,the expression of downstream target genes KLF4/VEGF and ANG-2 decreased compared to the control EA group(P<0.01).After miR-7 knockdown,the expression of KLF4/VEGF and ANG-2 increased(P<0.05 or P<0.01).Conclusions EA could promote angiogenesis in MCAO mice likely by inhibiting the expression of miR-7 and relieving inhibition of downstream target genes KLF4/VEG

关键词： electroacupuncture cerebral ischemia miRNA-7 angiogenesis Shuigou(GV 26) acupuncture points

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