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基于三维地球模型的中国大陆重力潮汐因子研究

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地球与行星物理论评（中英文） 2025年第1期56卷 83-93页

作者：王振宇赵倩中国地震局地震预测研究所北京100036

潮汐现象是地球对日、月等星体引力的响应,重力潮汐因子对于揭示地球内部结构具有重要作用.中国地震局、中国科学院等自20世纪80年代开始布设首批重力仪,用于研究中国大陆固体潮空间分布特征,到目前为止已建成超过50个台站的重力观测网... 详细信息

潮汐现象是地球对日、月等星体引力的响应,重力潮汐因子对于揭示地球内部结构具有重要作用.中国地震局、中国科学院等自20世纪80年代开始布设首批重力仪,用于研究中国大陆固体潮空间分布特征,到目前为止已建成超过50个台站的重力观测网络.本研究利用该网络的重力潮汐因子观测结果,结合考虑了横向非均匀效应的潮汐理论和三维地球模型,构建了中国大陆及周边地区的重力M_(2)、O_(1)因子分布模型.基于微扰理论,本研究发现P波速度扰动、S波速度扰动、密度扰动及综合效应对重力M_(2)因子影响的幅值范围分别为-0.12%至0.14%、-0.19%至0.17%、-0.08%至0.06%和-0.09%至0.11%(对O1因子的影响为-0.13%至0.28%、-0.27%至0.15%、-0.12%至0.10%和-0.15%至0.05%),影响最显著的区域为喜马拉雅造山带(负值)和华夏古陆东南缘(正值),体现了这些地区的特殊构造.本研究利用最小二乘配置方法对重力潮汐因子的理论值与实测值进行了融合,发现中国大陆及周边地区的重力M_(2)因子幅值范围为1.130至1.175,总体呈现周围低、中心高的特征.重力O1因子幅值范围为1.145至1.195,总体呈现从西北向东南逐渐升高的特征.以上结果可为中国大陆及周边地区重力潮汐因子、地球模型等相关研究提供参考.

关键词：重力潮汐因子三维地球模型数据融合

A one-dimensional strain-rate based model for soft structured clays

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Science China(Technological Sciences) 2012年第1期55卷 90-100页

作者： YIN zhenyu wang JianHua Center for Marine Geotechnics Research Department of Civil Engineering Shanghai Jiao Tong University Shanghai 200240 China

The paper aims to investigate the destructuration effect on the time-dependent behaviour of soft structured *** coupled with destructuration is analysed based on experimental observations.A strain-rate based model is developed to de-scribe the mechanical behaviour for both unstructured and structured clays under one-dimensional *** advantage of the proposed model lies in the determination of model parameters in a straightforward way,which leads to an easy use of the model for practical *** with consolidation,the model is used to simulate oedometer tests at constant rate of strain and long-term creep oedometer tests on two structured *** comparisons between predicted and measured results demonstrate that the proposed model can reasonably describe the effect of destructuration on the time-dependent behaviour of soft structured clay under one-dimensional *** the model is proposed for one-dimensional analysis,it can be a good base for developing a more general 3D model.

关键词： structured clays viscoplasticity consolidation creep strain.rate destructuration

Effect of sub-acute exposure to TiO_2 nanoparticles on oxidative stress and histopathological changes in Juvenile Carp (Cyprinus carpio)

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Journal of Environmental Sciences 2009年第10期21卷 1459-1466页

作者： HAO Linhua wang zhenyu XING Baoshan College of Environmentul Science and Engineering Ocean University of China Qingdao 266100 China. First Institute of Oceanography State Oceanic Administration Qingdao 266061 China. Department of Plant Soil and Insect Sciences University of Massachusetts Amherst MA 01003 USA.

Increasing application of nanotechnology highlights the need to clarify and understand nanotoxicity. Mammalian and in vitro studies have raised concerns about the toxicity of titanium dioxide nanoparticles （TiO2-NPs）, but there are limited data on ecotoxicity to aquatic organisms. In this work, the sub-acute toxicity of TiO2-NPs to carp （Cyprinus carpio） was assessed. Superoxide dismutase （SOD）, catalase （CAT） and peroxidase （POD） activities and lipid peroxidation （LPO） levels in liver, gill and brain tissues of carps varied with concentration of TiO2-NPs suspensions and exposure time （up to 8 d）. As a result, 100 and 200 mg/L TiO2-NPs caused statistically significant decrease in SOD, CAT and POD activities and significant increase in LPO levels in tissues （P 〈 0.05）, suggesting that the fish exposed to these two concentrations of TiO2-NPs suffered from the oxidative stress. The extent of depletion of antioxidant enzymes activities and the elevation of LPO in the liver was the greatest, indicating that the liver might be the most susceptible organ to TiO2-NPs exposure. In addition, carps had gill pathologies including edema and thickening of gill lamellae as well as gill filaments, and liver pathologies including necrotic and apoptosis hepatocytes after exposed to 100 and 200 mg/L TiO2-NPs for 20 d. These results indicated a potential risk from TiO2-NPs released into the aqueous environment.

关键词： TiO2 nanoparticles carp sub-acute toxicity oxidative stress histopathology

A new tunable elastic metamaterial structure for manipulating band gaps/wave propagation

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Applied Mathematics and Mechanics(English Edition) 2021年第11期42卷 1543-1554页

作者： zhenyu wang Zhaoyang MA Xingming GUO Dongsheng ZHANG Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy EngineeringShanghai UniversityShanghai 200444China

A one-dimensional mechanical lattice system with local resonators is proposed as an elastic metamaterial model,which shows negative mass and negative modulus under specific frequency *** proposed representative units,consisting of accurately arranged rigid components,can generate controllable translational resonance and achieve negative mass and negative modulus by adjusting the local structural parameters.A shape memory polymer is adopted as a spring component,whose Young’s modulus is obviously affected by temperature,and the proposed metamaterials’tunable ability is achieved by adjusting *** effect of the shape memory polymer’s stiffness variation on the band gaps is investigated detailedly,and the special phenomenon of intersecting dispersion curves is discussed,which can be designed and controlled by adjusting *** dispersion relationship of the continuum metamaterial model affected by temperature is obtained,which shows great tunable ability to manipulate wave propagation.

关键词： tunable elastic metamaterial negative mass negative modulus

Effect of tannic acid on corrosion behavior of carbon steel in NaCl solution

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Journal of Materials Science & Technology 2019年第1期35卷 64-75页

作者： Wenhua Xu En-Hou Han zhenyu wang Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal Research Chinese Academy of Sciences University of Chinese Academy of Sciences

Corrosion behavior of unrusted Q235 carbon steel was investigated in 3.5% NaCl solutions with 1–5 wt%tannic acid addition, using electrochemical methods including electrochemical impedance spectra(EIS),potentiodynamic polarization and scanning vibrating electrode technique(SVET) combined with surface analysis. Results show that the corrosion rate decreases with increasing tannic acid concentration. As compared with tannic acid-free solution, 1% tannic acid does not provide inhibition effect during the whole immersion, while inhibition effect is observed for 3% tannic acid after 8 h and for 5% tannic acid after 4 h. The inhibition efficiency by weight loss measurements(áw) for 1%, 3%, and 5% tannic is around-17.2%, 40.3%, and 51.5%, respectively. Corrosion of unrusted carbon steel in the presence of tannic acid is attributed to the joint effect of tannic acid adsorption and pH decrease. Formation of ferric-tannates is verified by X-ray photoelectron spectroscopy(XPS) and Raman spectra. The reaction mechanism between tannic acid and unrusted carbon steel is proposed.

关键词： Tannic acid Unrusted carbon steel Ferric-tannates EIS Corrosion

Lithospheric Equilibrium and Anisotropy around the 2021 Yangbi Ms 6.4 Earthquake in Yunnan,China

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Journal of Earth Science 2023年第4期34卷 1165-1175页

作者： Guangyu Fu zhenyu wang Jingsong Liu Yun wang Key Laboratory of Intraplate Volcanoes and Earthquakes(China University of Geosciences Beijing)Ministry of EducationBeijing 100083China Institute of Earthquake Forecasting China Earthquake AdministrationBeijing 100036China

Using the gravity/GNSS data of 318 stations observed in 2020,this paper optimizes the Bouguer and free-air gravity anomalies around the 2021 Yangbi Ms 6.4 Earthquake,inverses the lithospheric density structure of the focal area,and obtains the distribution of isostatic additional force borne by the *** results show that the Bouguer gravity anomaly in western Yunnan varies from-120 to-360 m *** a whole the anomalies are large in the north and small in the south,and the value in the source area of the 2021 Yangbi Ms 6.4 Earthquake is about-260 m *** lateral differences indicates that the crust around the great earthquake does not belong to a solid and stable tectonic *** lithosphere in the source area is basically in equilibrium,indicating that the occurrence of the great event is not relative to the lithospheric equilibrium,but to the differential movement of the crust in the horizontal *** addition,we obtain the teleseismic SKS phases of 51 *** a whole,the polarization direction of fast wave in western Yunnan is approximately vertical to the maximum gradient change direction of regional Bouguer gravity anomaly that reflects the change of Moho.

关键词： the 2021 Yangbi Ms 6.4 Earthquake Bouguer gravity anomaly density structure litho-spheric equilibrium shear waves shear wave splitting.

Will polycentric cities cause more CO2 emissions? A case study of 232 Chinese cities

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Journal of Environmental Sciences 2020年第10期32卷 33-43页

作者： Wei Sha Ying Chen Jiansheng Wu zhenyu wang Key Laboratory for Urban Habitat Environmental Science and Technology School of Urban Planning and DesignPeking UniversityShenzhen 518055China Laboratory for Earth Surface Processes Ministry of EducationCollege of Urban and Environmental SciencesPeking UniversityBeijing 100871China

From 2000 to 2010 China experienced rapid economic development and *** cities in economically developed areas have developed from a single-center status to *** this study,we used exploratory spatial data analysis (ESDA) to identify the population centers,which identified 232 cities in China as having urban *** was used to represent urban agglomeration,and POLYD (representing how far is the city’s sub-centers to the main center),POLYC (representing the number of a city’s centers),and POLYP (representing the population distributed between the main center and the sub-centers) were used to indicate urban *** light data were used to determine the CO2 emissions from various cities in China.A mixed model was used to study the impact of urban aggregation and polycentric data on the CO2 emission efficiency in 2000 and *** study found that cities with higher compactness were distributed in coastal areas,and the cities with higher multicentricity were distributed in the Yangtze River Delta and Shandong *** more compact the city was,the less conducive it was to improving CO2 emission *** development of the city was conducive to improving the CO2 emission efficiency,but the number of urban centers had no significant relationship with the CO2 emission *** research showed that the compactness and multicentricity of the city had an impact on the CO2 emission efficiency and provided some planning suggestions for the low carbon development of the city.

关键词： CO_2 emission efficiency polycentricity compactness Chinese cities

Artificial Intelligence Applications in the Development of Autonomous Vehicles:A Survey

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IEEE/CAA Journal of Automatica Sinica 2020年第2期7卷 315-329页

作者： Yifang Ma zhenyu wang Hong Yang Lin Yang Department of Information Technology and Decision Sciences Old Dominion UniversityNorfolkVA 23529 USA Department of Computational Modeling and Simulation Engineering Old Dominion UniversityNorfolkVA 23529 USA Department of Mechanical and Electrical Engineering Huazhong Agricultural UniversityWuhan 430070China

The advancement of artificial intelligence(AI)has truly stimulated the development and deployment of autonomous vehicles(AVs)in the transportation *** by big data from various sensing devices and advanced computing resources,AI has become an essential component of AVs for perceiving the surrounding environment and making appropriate decision in *** achieve goal of full automation(i.e.,self-driving),it is important to know how AI works in AV *** research have made great efforts in investigating different aspects of applying AI in AV ***,few studies have offered the research community a thorough examination of current practices in implementing AI in ***,this paper aims to shorten the gap by providing a comprehensive survey of key studies in this research ***,it intends to analyze their use of AIs in supporting the primary applications in AVs:1)perception;2)localization and mapping;and 3)decision *** investigates the current practices to understand how AI can be used and what are the challenges and issues associated with their *** on the exploration of current practices and technology advances,this paper further provides insights into potential opportunities regarding the use of AI in conjunction with other emerging technologies:1)high definition maps,big data,and high performance computing;2)augmented reality(AR)/virtual reality(VR)enhanced simulation platform;and 3)5G communication for connected *** paper is expected to offer a quick reference for researchers interested in understanding the use of AI in AV research.

关键词： Artificial intelligence(AI) autonomous vehicles(AVs) deep learning(DL) motion planning perception self-driving

Seed traits and taxonomic relationships determine the occurrence of mutualisms versus seed predation in a tropical forest rodent and seed dispersal system

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Integrative Zoology 2014年第3期9卷 309-319页

作者： zhenyu wang Lin CAO Zhibin ZHANG State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture Institute of ZoologyChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina

Although many studies have been carried out on plant-animal mutualistic assemblages,the roles of functional traits and taxonomy in determining both whether interactions involve mutualisms or predation and the structure of such assemblages are *** used semi-natural enclosures to quantitatively assess the interaction strengths between seeds of 8 sympatric tree species and 4 rodent species in a tropical forest in Xishuangbanna,Yunnan,Southwest *** found 2 clusters of species in the seed-rodent network represented by 2 genera in the Fagaceae(Castanopsis,Lithocarpus).Compared to seeds of 3 Castanopsis species,seeds with heavy weight,hard coat or caloric content(including 3 Lithocarpus species)were eaten less and more frequently hoarded by *** turn,hoarded seeds showed less predation and more mutualism with *** results suggest that seed traits significantly affected the hoarding behavior of rodents,and,consequently,the occurrence of mutualisms and predation as well as assemblage structure in the plant-animal seed dispersal ***nomically-related species with similar seed traits as functional groups belong to the same substructures in the *** results indicate that both seed traits and taxonomic relationships may simplify thinking about seed dispersal systems by helping to elucidate whether interactions are likely to be dominated by predation or mutualism.

关键词： hoarding behavior mutualism predation seed dispersal seed trait