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Geologic relationships and geochronology of the Cenozoic volcanoes and interbedded weathered mantles of Yulinshan in Qiangtang, North Tibet

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Chinese Science Bulletin 2000年第24期45卷 2214-2220页

作者： Lin Ding Yong Zhou jingjiang zhang Wanming Deng Chinese Acad Sci Inst Geol & Geophys Lab Lithosphere Tecton Evolut Beijing 100029 Peoples R China

The Yulinshan accumulations of volcanic rocks and interbedded weathered mantles provide a unique chance for studying the processes and environment of the formation of the planation surface in central Tibetan Plateau. Geochemical, 40Ar/39Ar and K/Ar geochronologic investigations of the weathered mantles and high-potassium volcanic rocks reveal that the volcano-weathered mantle accumulations formed under arid or semi-arid subtropic environment in 30-24 Ma. The sole planation surface of the Qiangtang region finally formed in about 20 Ma.

关键词： weathered mantle volcanic rock geochronology planation surface Tibetan Plateau.

Assessing the Influence of Aerosol on Radiation and Its Roles in Planetary Boundary Layer Development

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Journal of Meteorological Research 2021年第2期35卷 384-392页

作者： Zhigang CHENG Yubing PAN Ju LI Xingcan JIA Xinyu zhang Pengkun MA Qianqian WANG Junxia DOU jingjiang zhang Jiannong QUAN Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089

A comprehensive measurement of planetary boundary layer(PBL)meteorology was conducted at 140 and 280 m on a meteorological tower in Beijing,China,to quantify the effect of aerosols on radiation and its role in PBL *** measured variables included four-component radiation,temperature,sensible heat flux(SH),and turbulent kinetic energy(TKE)at 140 and 280 m,as well as PBL height(PBLH).In this work,a method was developed to quantitatively estimate the effect of aerosols on radiation based on the PBLH and radiation at the two heights(140 and 280 m).The results confirmed that the weakened downward shortwave radiation(DSR)on hazy days could be attributed predominantly to increased aerosols,while for longwave radiation,aerosols only accounted for around onethird of the enhanced downward longwave *** DSR decreased by 55.2 W m^(-2) on hazy days during noontime(1100–1400 local time).The weakened solar radiation decreased SH and TKE by enhancing atmospheric stability,and hence suppressed PBL *** with clean days,the decreasing rates of DSR,SH,TKE,and PBLH were 11.4%,33.6%,73.8%,and 53.4%,*** observations collectively suggest that aerosol radiative forcing on the PBL is exaggerated by a complex chain of interactions among thermodynamic,dynamic,and radiative *** findings shed new light on our understanding of the complex relationship between aerosol and the PBL.

关键词： planetary boundary layer(PBL) aerosol radiation sensible heat flux(SH) turbulence

Analysis of Boundary Layer Structure,Turbulence,and Flux Variations before and after the Passage of a Sea Breeze Front Using Meteorological Tower Data

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Journal of Meteorological Research 2023年第6期37卷 855-877页

作者： Ju LI Junxia DOU Donald H. LENSCHOW Mingyu ZHOU Lihong MENG Xiaobin QIU Yubing PAN jingjiang zhang Institute of Urban Meteorology(Key Laboratory of Urban Meteorology) China Meteorological AdministrationBeijing100089China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing100081China Beijing Research Center for Urban Meteorological Engineering and Technology Beijing100081China National Center for Atmospheric Research BoulderCO80307USA National Marine Environmental Prediction Center Beijing100081China Tianjin Key Laboratory for Oceanic Meteorology Tianjin300074China Tianjin Institute of Meteorological Science Tianjin300074China

A detailed analysis of a sea breeze front(SBF)that penetrated inland in the Beijing–Tianjin–Hebei urban agglomeration of China was *** focused on the boundary layer structure,turbulence intensity,and fluxes before and after the SBF passed through two meteorological towers in the urban areas of Tianjin and Beijing,*** changes in temperature,humidity,winds,CO_(2),and aerosol concentrations were observed as the SBF *** in these changes at the two towers mainly resulted from their distances from the ocean,boundary layer conditions,and background *** the SBF approached,a strong updraft appeared in the boundary layer,carrying near-surface aerosols aloft and forming the SBF *** was followed by a broad downdraft,which destroyed the near-surface inversion layer and temporarily increased the surface air temperature at *** feeder flow after the thermodynamic front was characterized by low-level jets horizontally,and downdrafts and occasional updrafts *** increased significantly during the SBF’s passage,causing an increase in the standard deviation of wind components in *** increase in turbulence was more pronounced in a stable boundary layer compared to that in a convective boundary *** passage of the SBF generated more mechanical turbulences,as indicated by increased friction velocity and turbulent kinetic energy(TKE).The shear term in the TKE budget equation increased more significantly than the buoyancy *** atmosphere shifted to a forced convective state after the SBF’s passage,with near isotropic turbulences and uniform mixing and diffusion of *** heat fluxes(latent heat and CO_(2)fluxes)showed positive(negative)peaks after the SBF’s passage,primarily caused by horizontal and vertical transport of heat(water vapor and CO_(2))during its *** study enhances understanding of boundary layer changes,turbulences,and fluxes during the passage of SBFs over u

关键词： sea breeze front boundary layer structure turbulence flux meteorological tower

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浅析土壤环境污染中监测技术的应用

工程建设（维泽科技） 2024年第5期7卷 195-197页

作者：李磊张敬讲河北领萃科技有限公司河北石家庄050000

随着我国经济的快速发展,土壤环境污染问题日益严重,对土壤环境污染监测技术的需求不断提高。文章旨在分析当前土壤环境污染监测技术的应用现状,探讨各类监测技术的优缺点,以期为我国土壤环境污染监测工作提供有益的借鉴。

关键词：土壤环境污染监测技术应用分析

DEVELOPMENTAL LAW OF GEOLOGICAL NATURAL DISASTERS AND ITS PROGNOSIS IN BEIJING-TIANJIN-TANGSHAN AREA——562 COMPREHENSIVE GEOLOGICAL BRIGADE THE MINISTRY OF GEOLOGY AND MINERAL RESOURCES

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中国地质科学院562综合大队集刊

中国地质科学院562综合大队集刊 1993年 120-127页

作者： zhang Yecheng Hu jingjiang Xu Bingchuaan zhang Liang Tang Changhan

The geological natural disasters are very *** endogenic pro- tess and exogenic process have been strong in both geological history and at *** population density of Beijing-Tianjin-Tangshan area is an enormous *** are the crowded cities and towns in this area and the rapid development of industry and agriculture and the activity of the humanity is exerting a great strong influence upon reformation and destru- ction of geological natural *** burden of environment is getting heavier in Beijing,Tianjin,Tangshan,Qinhuangdao and *** this condition the various geological natural disasters have continuously hap- pened and endangered people’s lives,properties and securities,and have blocked economic development of the society.

关键词： Tianjin humanity Bohai enormous getting reformation burden lives blocked securities

Bioinspired coacervate-based bioinks for construction of multiscale tissue engineering scaffolds

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Nano Research 2024年第9期17卷 8209-8219页

作者： Zhongwei Guo Shiqiang zhang Yilin Guo Jingjing Xia Xiao Wu Hao Hu Rongcheng Hu Fangli Huang Qiulei Gao Chun Liu jingjiang Qiu Wei Sun School of Mechanics and Safety Engineering Zhengzhou UniversityZhengzhou 450001China Department of Mechanical Engineering and Mechanics Tsinghua UniversityBeijing 100084China Precision Medicine Institute Guangdong Provincial Key Laboratory of Orthopedics and TraumatologyThe First Affiliated Hospital of Sun Yat-sen UniversityGuangzhou 510080China Department of Mechanical Engineering Drexel UniversityPhiladelphiaPA 19104USA

Engineering hydrogels that resemble biological tissues of various lengths via conventional fabrication techniques remains ***-dimensional(3D)bioprinting has emerged as an advanced approach for constructing complex biomimetic 3D architectures,which are currently restricted by the limited number of available bioinks with high printability,biomimicry,biocompatibility,and proper mechanical *** by ubiquitous coacervation phenomena in biology,we present a unique mineral-biopolymer coacervation strategy that enables the hierarchical assembly of nanoclay and recombinant human collagen(RHC).This system was observed to undergo a coacervation transition(liquid‒liquid phase separation)*** formed dense phase separated from its supernatant is the coacervate of clay-RHC-rich complexes,where polymer chains are sandwiched between silicate *** dynamics simulation was first used to verify and explore the coacervation ***,the coacervates were demonstrated to be potential bioinks that exhibited excellent self-supporting and shear-thinning viscoelastic *** extrusion-based printing,the versatility of the bioink was demonstrated by reconstructing the key features of several biological tissues,including multilayered lattice,vascular,nose,and ear-like structures,without the need for precrosslinking operations or support ***,the printed scaffolds were cytocompatible,elicited minimal inflammatory responses,and promoted bone regeneration in calvarial defects.

关键词： bioinks coacervation mineral-biopolymer nanoclay tissue engineering scaffold

Preliminary Research on GNSS Multipath Interpret the Process of Vegetation Growth

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Preliminary Research on GNSS Multipath Interpret the Process...

DEVELOPMENTAL LAW OF GEOLOGICAL NATURAL DISASTERS AND ITS PROGNOSIS IN BEIJING-TIANJIN-TANGSHAN AREA——562 COMPREHENSIVE GEOLOGICAL BRIGADE THE MINISTRY OF GEOLOGY AND MINERAL RESOURCES

第十一届中国卫星导航年会

作者： Jilun Peng Shuangcheng zhang jingjiang zhang Qi Liu Tao Wang College of Geology Engineering and Geomantic Chang’an University Institute of Desert Meteorology in China Meteorological Administration Institute of Urban Meteorology CMA

Vegetation is a significant link between soil, moisture, organisms and the atmosphere. Recording vegetation changes has important significance in climate change. Traditional remote sensing has the dra

关键词： GNSS Multipath NDVI Vegetation growth Phenology

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DEVELOPMENTAL LAW OF GEOLOGICAL NATURAL DISASTERS AND ITS PR...

Nano friction behaviour between magnetic materials and copper considering the inter-diffusion effect

作者： zhang Yecheng Hu jingjiang Xu Bingchuaan zhang Liang Tang Changhan

＜正＞The geological natural disasters are very *** endogenic pro- tess and exogenic process have been strong in both geological history and at *** population density of Beijing-Tianjin-Tangshan area is an enormous *** are the crowded cities and towns in this area and the rapid development of industry and agriculture and the activity of the humanity is exerting a great strong influence upon reformation and destru- ction of geological natural *** burden of environment is getting heavier in Beijing,Tianjin,Tangshan,Qinhuangdao and *** this condition the various geological natural disasters have continuously hap- pened and endangered people’s lives,properties and securities,and have blocked economic development of the society.

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Friction 2024年第7期12卷 1532-1547页

作者： Zilin LI Lisha DOU Shiyu YANG Huajiang OUYANG Qichen ZHU Xiaoyang CHEN Xin JIA Shuaiwei DOU Xiaolong CUI Yudong zhang jingjiang QIU Guochen QI Bangbang NIE Pan LIU Ronghan WEI School of Mechanics and Safety Engineering Zhengzhou UniversityZhengzhou 450001China Engineering Technology Research Center of Henan Province for MEMS Manufacturing and Application Zhengzhou UniversityZhengzhou 450001China Institute of Intelligent Sensing Zhengzhou UniversityZhengzhou 450001China School of Engineering University of LiverpoolLiverpool L693GHUK School of Cyber Science and Engineering&Hanwei Institute of Internet of Things Zhengzhou UniversityZhengzhou 450001China

Copper,permalloy,cobalt,and silicon are the materials that have been widely utilised in magnetic *** the size of interest is down to the nanoscale,the inter-diffusion between certain materials becomes *** paper studies the nanoscale friction characteristics between frictional pairs with and without inter-diffusion properties through the atomic force *** distinct evolution features of nanoscale friction force when inter-diffusion is involved are discovered experimentally,which is also confirmed through theoretical ***,through the thin film deposition method,four pairs of contact materials(Cu–Ni_(81)Fe_(19),Si–Ni_(81)Fe_(19),Cu–Co,Cu–Si)are designed for friction tests,in which diffusion occurs at the interface of Cu–Ni_(81)Fe_(19)***,the effects of sliding velocity and loading force on the nano friction of each pair are *** is found that regardless of the diffusion phenomenon:(1)the adhesion force values exhibit a notable correlation to the values of the friction force;(2)the friction force in all four material pairs consistently increases with the growth of the normal loading force,although the growth rate may *** terms of the sliding velocity effect,the friction forces of immiscible materials(Si–Ni_(81)Fe_(19),Cu–Co,and Cu–Si)are found to increase with the increasing sliding ***,the friction force of Cu–Ni_(81)Fe_(19),decreases with the increasing sliding ***,a compositive friction model considering both the velocity and the normal force effect was proposed,which shows good agreement with the experimental results and explains the nano friction behaviour of both miscible and immiscible metals.

关键词： atomic force microscope friction force normal load sliding velocity