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Numerical study on the flow field characteristics of the new high-speed maglev train in open air

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2020年第5期21卷 366-381页

作者： Peng ZHOU Tian LI chun-fa zhao Ji-ye ZHANG State Key Laboratory of Traction Power Southwest Jiaotong UniversityChengdu 610031China

With the increasing demand of higher travelling speed,a new streamlined high-speed maglev train has been designed to reach a speed of 600 km/*** better capture the flow field structures around the maglev train,an improved delayed detached eddy simulation(IDDES)is adopted to model the *** show that the new maglev train has good aerodynamic load performance such as small drag coefficient contributing to energy *** main frequencies of aerodynamic forces for each car have a scattered *** are two pairs of counter-rotating large vortices in the non-streamlined part of the train that make the boundary layer *** high-intensity vortices are distributed in the narrow space between skirt plates or train floor and *** the gap between the train floor and track(except near the tail car nose),the main frequency of vortex shedding remains constant and its strength increases exponentially in the streamwise *** the wake,the counter-rotating vortices gradually expand and reproduce some small vortices that move *** vortex has quite random and complex frequencydomain distribution characteristics in the *** maximum time-averaged velocity of the slipstream occurs near the nose of the head car,based on which,the track-side safety domain is divided.

关键词： Maglev train High-speed Improved delayed detached eddy simulation(IDDES) Aerodynamic load Vortex Time-averaged slipstream

Research of the eradication of Helicobacter pylori to prevent gastric cancer

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Gastroenterology & Hepatology Research 2023年第1期5卷 1-5页

作者： zhao-chun Chi Department of Gastroenterology Qingdao Municipal HospitalQingdao 266011China

Gastric cancer(GC)is primarily caused by Helicobacter pylori(***).Approximately 50%of Chinese people have ***,and *** is responsible for 90%of stomach cancer *** far,the best method of preventing the development of stomach cancer is the inhibition of *** incidence and fatality rates of stomach cancer can be considerably reduced by population-based *** eradication.

关键词： prevention gastric cancer metachronous occurrence epigenetic chemoprevention

Relationship between Extreme Precipitation and Temperature in Two Different Regions:The Tibetan Plateau and Middle–East China

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Journal of Meteorological Research 2019年第5期33卷 870-884页

作者： Rui WANG Tao XIAN Mengxiao WANG Fengjiao CHEN Yuanjian YANG Xiangdong ZHANG Rui LI Lei ZHONG chun zhao Yunfei FU School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Anhui Meteorological Information Center Anhui Institute of Meteorological SciencesHefei230061China School of Atmospheric physics Nanjing University of Information Science&TechnologyNanjing 210044China International Arctic Research Center and Department of Atmospheric Sciences University of Alaska FairbanksAK 99775USA

The change of extreme precipitation with temperature has regional characteristics in the context of global *** this study, radiosonde data, co-located rain gauge(RG) observations, and Tropical Rainfall Measuring Mission(TRMM) precipitation radar(PR) products are used to explore the relationship between extreme precipitation intensity and near-surface temperature in Middle–East China(MEC) and the eastern Tibetan Plateau(TP) during1998–2012. The results show that extreme precipitation intensity increases with increasing temperature at an approximate Clausius–Clapeyron(C–C) rate(i.e., water vapor increases by 7% as temperature increases by 1°C based on the C–C equation) in MEC and TP, but the rate of increase is larger in TP than in MEC. This is probably because TP(MEC) is featured with deep convective(stratiform) precipitation, which releases more(less) latent heat and strengthens the convection intensity on a shorter(longer) timescale. It is also found that when temperature is higher than 25°C(15°C) in MEC(TP), the extreme precipitation intensity decreases with rise of temperature, suggesting that the precipitation intensity does not always increase with warming. In this case, the limited atmospheric humidity and precipitable water could be the primary factors for the decrease in extreme precipitation intensity at higher temperatures.

关键词： extreme precipitation Clausius–Clapeyron(C–C) rate temperature humidity precipitable water

Synthesis and Characterization of NASICON Nanoparticles by Sol-gel Method

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Chemical Research in Chinese Universities 2009年第1期25卷 13-16页

作者： WANG Biao LIANG Xi-shuang LIU Feng-min ZHONG Tie-gang zhao chun LU Ge-yu QUAN Bao-fu State Key Laboratory on Integrated Optoelectronics College of Electronic Science and Engineering Jilin University Changchun 130012 P. R. China

Na superionic conductor（NASICON） nanoparticles were synthesized by a modified sol-gel method and sintered at a temperature range of 800--1000℃. The performance of the samples was characterized by the analysis methods of X-ray diffraction（XRD）, Fourier transform infrared spectroscopy（FTIR）, and transmission electron microscopy（TEM） as well as conductivity measurement. Compared with those sintered at other temperatures, the NASICON material sintered at 900 ℃ had the best crystalline structure and higher conductivity.

关键词： Na superionic conductor(NASICON) Nanoparticles Sol-gel method

ASSESSMENT OF WATER RESOURCES AT HONGHE NATIONAL NATURE RESERVE

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湿地科学 2004年第2期2卷 145-152页

作者： LIU Zheng-Mao LU Xian-Guo zhao chun-Hui zhao Yan-Bo QI Han-Qiang CollegeofMunicipalandEnvironmentalEngineering HarbinInstituteofTechnologyHarbinHeilongjiang150090China NortheastInstituteofGeographyandAgriculturalEcology CASChangchunJilin130012China HeilongjiangAgriculturalReclamationSurvey DesignandResearchInstituteJiamusiHeilongjiang154002China

A detailed assessment on water resources of HNNR is to find the changing rules in time and space scale of water resources of HNNR and its adjacent areas, and the generating and degrading factors of wetland and provide scientific base on restoring and managing the hydrologic regime for planning and designing at HNNR. Both the assessment area and its adjacent watershed of Bielahong River belong to the same region in the climate and surface features. Total of 46 years of serial data from 1956 2001 in the Bielahong Hydrology Station was employed. Typical analysis of the serial runoff was conducted by adopting the residual mass curve method. The calculation methods of hydrological parameters are valuable for analyzing the water balance of HNNR. The results showed that the inputs of 118.29×10 6 m 3 of the surface runoff and 1 478km 2 of the areas of natural watershed in HNNR were decreased. At the same time some measurements to control and prevent water resources decreased have been proposed.

关键词：洪河生态系统水资源生态环境环境保护

Sophaloseedlines A-G: Diverse Matrine-Based Alkaloids from Sophora alopecuroides with Potential Anti-Hepatitis B Virus Activities

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Chinese Journal of Chemistry 2021年第9期39卷 2555-2562页

作者： Ding Luo Zhong-Nan Wu Ji-Hui Zhang Qiang Lin Neng-Hua Chen Si Chen Qing Tang zhao-chun Zhan chun-Lin Fan Yao-Lan Li Guo-Cai Wang Yu-Bo Zhang Institute of Traditional Chinese Medicine&Natural Products Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs ResearchCollege of PharmacyJinan UniversityGuangzhouGuangdong 510632China Guangdong Clinical Translational Center for Targeted Drug Department of PharmacologySchool of MedicineJinan UniversityGuangzhouGuangdong 510632China

Sophaloseedlines A-G(1-7),seven new matrine-based alkaloids along with two known analogues,were isolated from the seeds of Sophora *** new structures were determined based on extensive spectroscopic data,electronic circular dichroism calculations,and X-ray ***,sophaloseedline A(1)represents a novel rearranged 6(5→17)-abeo-matrine alkaloid featuring unprecedented highly constructed 7/6/5/6 tetracyclic fused ring *** hypothetical biosynthetic pathways for sophaloseedli nes A-F were proposed based on co-existing ***,all the isolated alkaloids were screened for their antiviral activities against hepatitis B virus,and new alkaloids 1 and 2 displayed more potent activities than those of matrine(a parent alkaloid of title plant)and positive control(lamivudine).

关键词： Sophora alopecuroides Matrine-based alkaloid Structure elucidation Anti-HBV activity Biological activity

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拉康的精神分析伦理学:一种批判的姿态

外国文学研究 2021年第5期43卷 93-105页

作者：赵淳四川外国语大学

精神分析伦理学是整个伦理学知识谱系中不可或缺的一环,也是文学伦理学批评的理论支撑之一。通过对亚里士多德、边沁、康德、萨德、弗洛伊德的伦理观进行清理和质疑,拉康敏锐看到,亚里士多德那种带有强烈等级属性的"善"不可能属于多数人... 详细信息

精神分析伦理学是整个伦理学知识谱系中不可或缺的一环,也是文学伦理学批评的理论支撑之一。通过对亚里士多德、边沁、康德、萨德、弗洛伊德的伦理观进行清理和质疑,拉康敏锐看到,亚里士多德那种带有强烈等级属性的"善"不可能属于多数人,人们也无法如启蒙哲学家呼吁的那样"爱邻犹爱己"。精神分析的伦理要求主体遵从自身欲望,而主体欲望来自于体现为象征秩序的大他者的欲望。虽然囿于认知局限,拉康从未从社会、历史、文化的角度对伦理的内容进行过填充,但他却撼动了此前西方几乎所有关于善的认知。貌似空洞的精神分析伦理学,实则将某种对传统伦理思想进行全面重审、修正、甚至颠覆的诉求铭刻到了自身的内在逻辑之中。这种否定的动因恰如其分地呈现了精神分析伦理学的批判姿态,批判的目标乃是权力话语之下的主人伦理和宣称为了所有人福祉的虚伪道德。

关键词：拉康精神分析伦理学批判性亚里士多德康德

Preparation of Porous ZrO_2 and Study on Its Properties

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Chemical Research in Chinese Universities 2002年第3期18卷 337-340页

作者： zhao chun YANG Shao feng SONG Li zhu XU Hui fang YANG Hua JIANG Fu ming WANG Zi chen NIU Zhong guo Department of Chemistry Jilin UniversityChangchun 130023P.R.China Department of Electronic Engineering Jilin UniversityChangchun 130023P.R.China

The porous zirconia powder with a high surface area was synthesized by means of the ion exchange method from surfactant CTMAB. The highest surface area of the resulted zirconia reached 340 m 2/g having been calcined at 500 ℃ for 2 h. The influence of preparing conditions on the surface area was investigated. The results show that the amount of the surfactant and the aging time were two main factors affecting the surface area of zirconia. The IR analysis indicated that the large surface area was related to the cations of the surfactant which incorporated into hydrous zirconia by ion exchange.

关键词： Porous zirconia CTMAB Surfactant

Self-Assembled Porous-Reinforcement Microstructure-Based Flexible Triboelectric Patch for Remote Healthcare

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Nano-Micro Letters 2023年第7期15卷 324-336页

作者： Hao Lei Haifeng Ji Xiaohan Liu Bohan Lu Linjie Xie Eng Gee Lim Xin Tu Yina Liu Peixuan Zhang chun zhao Xuhui Sun Zhen Wen Institute of Functional Nano and Soft Materials(FUNSOM) Joint International Research Laboratory of Carbon-Based Functional Materials and DevicesSoochow UniversitySuzhou 215123People’s Republic of China Department of Electrical and Electronic Engineering School of Advanced TechnologyXi’an Jiaotong-Liverpool UniversitySuzhou 215123People’s Republic of China Department of Applied Mathematics School of Mathematics and PhysicsXi’an Jiaotong-Liverpool UniversitySuzhou 215123People’s Republic of China Department of Electrical and Electronic Engineering University of LiverpoolLiverpool L693GJUK Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices Soochow UniversitySuzhou 215123JiangsuPeople’s Republic of China

Realizing real-time monitoring of physiological signals is vital for preventing and treating chronic diseases in elderly individuals. However,wearable sensors with low power consumption and high sensitivity to both weak physiological signals and large mechanical stimuli remain ***, a flexible triboelectric patch(FTEP) based on porous-reinforcement microstructures for remote health monitoring has been reported. The porousreinforcement microstructure is constructed by the self-assembly of silicone rubber adhering to the porous framework of the PU sponge. The mechanical properties of the FTEP can be regulated by the concentrations of silicone rubber dilution. For pressure sensing, its sensitivity can be effectively improved fivefold compared to the device with a solid dielectric layer, reaching 5.93 kPa^(-1) under a pressure range of 0–5 kPa. In addition, the FTEP has a wide detection range up to 50 kPa with a sensitivity of 0.21 kPa^(-1). The porous microstructure makes the FTEP ultra-sensitive to external pressure, and the reinforcements endow the device with a greater deformation limit in a wide detection range. Finally, a novel concept of the wearable Internet of Healthcare(Io H) system for real-time physiological signal monitoring has been proposed, which could provide real-time physiological information for ambulatory personalized healthcare monitoring.

关键词： Pressure sensor Triboelectric nanogenerator Porous dielectric layer Physiological signals Internet of Healthcare