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Journal of Environmental Sciences 2001年第2期13卷 180-184页

作者： J S Wang z f yang S S Li z M Wang Institute of Environmental Sciences Beijing Normal University State Key Joint Laboratory of Environmental Simulation and Pollution Control Beijing 100875 China.

The radionuclide migration from a certain Chinese repository with low-intermediate level radioactive solid waste is studied. The migration in groundwater is analyzed and computed in detail. Under presumption of normal releasing, or the bottom of the repository has been marinated for one month with precipitation reaching 600 mm once and a 6 m aerated zone exists, a prediction for 7 radionuclides is conducted. It shows that the aerated zone is the primary barrier for migration. The migration for radionuclides 60Co, 137Cs, 90Sr, 63Ni, etc. will be retarded in it within 500 years. The concentration of 239Pu will be decreased by amount of 6 order. Only 3H and 14C can migrate through the aerated zone. The radionuclides that go through the aerated zone and enter the aquifer will exist in spring, stream and sea. Based on this, the intake dose by residents in different age group resulting from drinking contaminated spring water, eating seafood is calculated. The results showed that the impact of the repository to the key resident group is lower than the limit in national repository regulation standard. This complies with the repository management target.

关键词： intermediate level radioactive waste repository Environmental impact of radionuclide migration in groundwater from a low

Precipitation of multi-type nano-quasicrystals in a Mg-zn-Y alloy

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Journal of Magnesium and Alloys 2024年第3期12卷 997-1008页

作者： W.z.Wang X.z.zhou L.f.zhang H.Q.Ye z.Q.yang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of ScienceShenyang 110016China Ji Hua Laboratory Foshan 528251China foshan University Foshan 528231China

Mg-6zn-1Y(at.%)ribbons with strengthening precipitates of multi-type nanoquasicrystals were prepared by melt-spinning followed by aging *** evolution of the rapidly solidified ribbons during isothermal aging was comprehensively studied using various electron microscopy *** new kinds of decagonal quasicrystals were formed in aged ribbons,in addition to precipitation of nanometer icosahedral ***-resolution observations reveal that both decagonal quasicrystals can be modeled by quasiperiodic tiling with decagonal clusters of 2.5 nm in diameter,but overlap of neighboring clusters in both decagonal quasicrystals is different from the Gummelt model observed in other quasicrystals.A shell composed of complex Laves Mg-zn domains was formed surrounding each decagonal quasicrystal precipitate upon prolonged *** addition,all kinds of nanoprecipitates exhibit excellent structure and size stability at 573 *** findings may have implications for not only fundamental studies about quasicrystals,but also microstructural manipulation of high-performance Mg alloys.

关键词： Quasicrystal Mg alloys Rapid solidification Scanning-transmission electron microscopy.

Microstructure evolution and shape memory behaviors of Ni_(47)Ti_(44)Nb_(9)alloy subjected to multistep thermomechanical loading with different prestrain levels

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Journal of Materials Science & Technology 2024年第4期171卷 80-93页

作者： Y.H.zhang H.Li z.W.yang X.Liu Q.f.Gu State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of High-Performance Precision forming Technology and Equipment Northwestern Polytechnical UniversityXi’an 710072China

Ni_(47)Ti_(44)Nb_(9)shape memory alloy(SMA)is a promising material in the aerospace field due to its wide transformation *** application of shape memory effect depends on multistep thermomechan-ical loading,viz.,low-temperature deformation and subsequent heating to ***-temperature deformation prestrain plays a pivotal role in shape memory properties tailoring of SMA ***,microstructure evolution and deformation mechanisms of Ni_(47)Ti_(44)Nb_(9)SMA subjected to vari-ous prestrain levels are still *** this end,microstructure evolution and shape memory behaviors of Ni_(47)Ti_(44)Nb_(9)alloy subjected to multistep thermomechanical loading with prestrain levels of 8%-16%at-28℃(M_(s)+30℃)were *** results demonstrate that the stress-strain curve of the specimen exhibits four distinct stages at a maximal prestrain of 16%.Whereas stageⅡand stageⅢend at prestrains of∼8%and∼12%,*** stageⅡ,the stress-induced martensitic transformation is accompanied by the dislocation slip of the NiTi matrix andβ-Nb *** stageⅢ,in addition to the higher density of dislocations and further growth of stress-induced martensite variants(SIMVs),(001)compound twins are introduced as a result of the(001)deformation twinning in stress-induced ***{20-1}martensite twins are gradually introduced in stageⅣ.Correspondingly,after subsequent unloading and heating,a higher density of{114}austenite twins form in the specimen with a larger prestrain of 16%.With increasing prestrain from 8%to 16%,the recoverable strainε_(re)^(T)upon heating increases first and then ***ε_(re)^(T)obtains a maximum of 7.03%at 10%prestrain and de-creases to 6.17%at 16%*** increase ofε_(re)^(T)can be attributed to the formation of new SIMVs,the further growth of existing SIMVs,and the recoverable(001)compound *** the decrease ofε_(re)^(T)is mainly associated with the irrecoverable strain by{20−1}martensite *** effe

关键词： Ni_(47)Ti_(44)Nb_(9)shape memory alloy Wide transformation hysteresis Thermomechanical loading Microstructure evolution Shape memory behaviors Stress-induced martensitic transformation Deformation twinning

Reactive destabilization and bidirectional catalyzation for reversible hydrogen storage of LiBH_(4) by novel waxberry-like nano-additive assembled from ultrafine fe_(3)O_(4) particles

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Journal of Materials Science & Technology 2024年第6期173卷 63-71页

作者： S.Wang M.H.Wu Y.Y.zhu z.L.Li Y.X.yang Y.z.Li H.f.Liu M.X.Gao Department of Material Science Shenzhen MSU-BIT UniversityShenzhen 518172China State Key Laboratory of Silicon and Advanced Semiconductor Materials&School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China Institute of Resources Utilization and Rare Earth Development State Key Laboratory of Rare Metals Separation and Comprehensive UtilizationGuangdong Provincial Key Laboratory of Rare Earth Development and ApplicationGuangdong Academy of SciencesGuangzhou 510650China Institute of Science and Technology for New Energy Xi’an Technological UniversityXi’an 710021China National Supercomputing Center in Shenzhen Shenzhen 518055China

LiBH_(4) containing 18.5 wt.%H_(2) is an attractive high-capacity hydrogen storage material,however,it suffers from high operation temperature and poor ***,a novel and low-cost bifunctional additive,waxberry-like fe_(3)O_(4) secondary nanospheres assembled from ultrafine primary fe_(3)O_(4) nanoparticles,is synthesized,which exhibits significant destabilization and bidirectional catalyzation towards(de)hydrogenation of LiBH_(4).With an optimized addition of 30 wt.% waxberry-like fe_(3)O_(4),the system initiated dehydrogenation below 100℃ and released a total of 8.1 wt.%H_(2) to 400℃.After 10 cycles,a capacity retention of 70% was achieved,greatly superior to previously reported oxides-modified *** destabilizing and catalyzing mechanisms of waxberry-like fe_(3)O_(4) on LiBH_(4) were systematically analyzed by phase and microstructural evolutions during dehydrogenation and hydrogenation cycling as well as density functional theory(DfT)*** present work provides new insights in developing advanced nano-additives with unique structural and multifunctional designs towards LiBH4 hydrogen storage.

关键词： LiBH_(4) Hydrogen storage Waxberry-like fe_(3)O_(4) Destabilization Catalysis

Retrospect and prospect of watershed hydrological model

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Communications in Nonlinear Science and Numerical Simulation 2001年第3期6卷 172-177页

作者： B. CHEN, L. z. XIA, z. f. yang and G. Q. CHEN State Key Laboratory for Studies of Turbulence and Complex Systems / Center for Environmental Sciences, Peking University, Beijing 100871, China Institute of Environmental Sciences, Beijing Normal Universitg, State Key Lab. Studs. T./C.S. Center for Environmental Sciences Peking University Beijing 100871 China Institute of Environmental Sciences Beijing Normal University Beijing 100875 China

A brief review is presented of the development of watershed hydrological models. Conventional Hydrological Model, Grey Hydrological Model, Digital Hydrological Model and Intelligent Hydrological Model are analyzed. The frameworks of fuzzy Cognitive Hydrological Model and Integrated Digital Watershed Hydrological Model are presented.

关键词： watershed hydrological model digital watershed complex system

Scientific discovery of a unique cloud-shaped rock pillar in an ancient quarry in zhejiang Province

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Scientific discovery of a unique cloud-shaped rock pillar in...

Triggers of rockfall on a slope related to large ancient underground caves cultural heritage(China)

中国科学院地质与地球物理研究所2015年度（第15届）学术年会

作者： L.Deng L.H.Li z.f.yang Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of Sciences

In this paper,one unique cloud-shaped nock pillar is discovered in an ancient quarry in zhejiang Province,Textual research indicates that this ancient quarry was initially exploited La Liang Dynasty(502-557 BC}.Geological conditions of the ancient quarry arc elaborated in this *** investigation results indicate that this rock pillar was left during *** reconstruction through the data acquired by 3D laser scanning presents that ii has a complex ***-Dimensional finite difference stimulation using Mohr-Coulomb parameters acquired from back analysis has been conducted to analyze its stress distribution and *** results suggest a maximum stress of1,7 MPa in this pillar,the stress reduces from bottom to top,and from one side to the opposite side of the pillar,and finally the stress exhibits a similar *** displacement in B side reduces from bottom to top,then increases reversely.

关键词：

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Triggers of rockfall on a slope related to large ancient und...

In situ digital testing method for quality assessment of soft soil improvement with polyurethane

中国科学院地质与地球物理研究所2015年度（第15届）学术年会

作者： X.L.Wang L.Q.zhang z.f.yang Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of Sciences

The large underground ancient caves of feifeng Mountain(30,000 m2 China),located at zhejiang Province,eastern of China,were formed by excavating the tuffaceous rocks for building stones in the ancient *** study area lies at the contact between Upper Jurassic and Upper Cretaceous sedimentary *** considering the southern slope of the feifeng Mountain where the ancient caves are located,we observe the presence of a soft muddy-siltstone layer separating different tuffaceous *** thickness of the soft layer is about 15 in,and it plays an important role in the stability of the *** main faults control the structural setting of feifeng Mountain:a thrust-compressional fault,with dip of 70°to 80°and dip direction of 300°;a NW fault,with dip of 75°to 85°and dip direction of 210°;and a EW fault nearest to feifeng *** tectonic structures including tectonic faults and tectonic joints have the similar geometric characteristics at the local and regional ***,the location of rockfall has a strong relationship with the geometric characteristics of tectonic joints at the local *** triggers of the rockfall in the study area include the tectonic structures,special stratum(stuff and thick soft layer),and finally the excavation in ancient time was defined.

关键词： ancient underground caves cultural heritage tectonic structures rockfall

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1732-1748页

作者： X.f.Wang C.J.Wang W.V.Yue z.J.zhang z.Q.Yue Department of Civil Engineering China University of Geosciences (Beijing)BeijingChina Department of Water Science and Engineering Zhengzhou UniversityZhengzhouChina Department of Geotechnical Engineering Tongji UniversityShanghaiChina Department of Civil Engineering The University of Hong KongChina

This study purposes an in situ testing method on quality assessment of soil *** drilling data includes the spatial distribution and in situ strength of untreated and treated soil along three different drillholes measured by on-site drilling monitoring *** factual drilling data can characterize the degree of soil improvement by penetration injection with permeable *** from on-site drilling monitoring shows that the linear zones represent constant drilling speeds shown in the plot of drill bit advancement *** drilling time,which indicates the spatial distributions of soil *** soil profile at the study site is composed of four layers,which includes fill,untreated silty clay,treated silty clay,and mucky *** results of soil profile are verified by the parallel site *** constant drilling speeds profile the coring-resistant strength of drilled *** comparing with the untreated silty clay,the constant drilling speeds of the treated silty clay have been decreased by 13.0-62.8%.Two drilling-speed-based indices of 61.2%and 65.6%are proposed to assess the decreased average drilling speed and the increased in situ strength of treated silty *** tests,*** compressive strength(UCS)test,have been performed with core sample to investigate and characterize in situ strength by comparing that with drilling *** show that the average predicted strengths of treated silty clay are 2.4-6.9 times higher than the average measured strength of untreated silty *** UCS-based indices of 374.5%and 344.2%verified the quality assessment(QA)results by this new in situ *** method provides a cost-effective tool for quality assessment of soil improvement by utilizing the digital drilling data.

关键词： Drilling process monitoring system Hydraulic rotary drilling process Constant drilling speed Soil improvement Quality assessment

Investigation on the gutters in caverns Nos.1-5 of Longyou Caverns

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Investigation on the gutters in caverns Nos.1-5 of Longyou C...

Research on fine-Grained RecognitionMethod for Sensitive Information in Social Networks Based on CLIP

中国科学院地质与地球物理研究所2015年度（第15届）学术年会

作者： Y.f.Tan L.H.Li W.T.He z.f.yang Y.fu Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of Science Longyou Grottoes Research Institute

Work on groundwater hydraulics is one of the most complicated issues in underground *** an ancient engineering,Longyou rock caverns are famous for the scale,the building technique and the impressive drainage *** to the field study,52 gutters and 6 water traps exist in caverns ***,only one drainage ditch was found in cavern No.2 due to later exploitation in *** paper mainly presents the intention,layout and types of the gutters,whereby the scientific,historical and aesthetic values are acknowledged based on the above *** knowledge achieved from this research could be useful for the design of the modern drainage system in cavern Nos.1-5.

关键词： water proof gutter underground engineering Longyou Caverns

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Computers, Materials and Continua 2024年第1期81卷 1565-1580页

作者： zhang M. Shan f. Liu M. Wang z. School of Computer Science Zhongyuan University of Technology Zhengzhou 450007 China Henan Key Laboratory of Cyberspace Situation Awareness Zhengzhou 450001 China

With the emergence and development of social networks, people can stay in touch with friends, family, and colleaguesmore quickly and conveniently, regardless of their location. This ubiquitous digital internet environment has also ledtolarge-scaledisclosureof personal *** tothe complexity andsubtletyof sensitive information, traditional sensitive information identification technologies cannot thoroughly address the characteristics of each piece of data, thus weakening the deep connections between text and images. In this context, this paper adopts the CLIP model as a modality discriminator. By using comparative learning between sensitive image descriptions and images, the similarity between the images and the sensitive descriptions is obtained to determine whether the images contain sensitive information. This provides the basis for identifying sensitive information using different modalities. Specifically, if the original data does not contain sensitive information, only single-modality text-sensitive information identification is performed; if the original data contains sensitive information, multimodality sensitive information identification is conducted. This approach allows for differentiated processing of each piece of data, thereby achieving more accurate sensitive information identification. The aforementioned modality discriminator can address the limitations of existing sensitive information identification technologies, making the identification of sensitive information from the original data more appropriate and precise. © 2024 The Authors. Published by Tech Science Press.

关键词： Deep learning multi-modal fusion sensitive information recognition social networks