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Measuring flow velocity on frozen and non-frozen slopes of black soil through leading edge method

International Soil and Water Conservation Research 2017年第3期5卷 180-189页

作者： Chao Chen Yunyun Ban Xuefeng Wang Tingwu Lei College of Water Resources and Civil engineering China Agricultural UniversityQinghua DongluBeijing100083PR China state key {2. of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationChinese Academy of Science and Ministry of Water ResourcesYanglingShaanxi Province 712100PR China

Flow velocity is a major parameter related to hillslope hydrodynamics *** study aims to measure flow velocity over frozen and non-frozen slopes through leading edge method before being calibrated with accurate flow velocity to determine the correct coefficient for convenience of flow velocity *** experiments were conducted on frozen and non-frozen soil slopes with flumes involving four slope gradients of 5°,10°,15°,and 2.°and three flow rates of 1,2.and 4 L/min with a flume of 6 m long and 0.1 m *** measurements were made with a stopwatch to record the time duration that the water flow ran over the rill segments of 2.4 and 6 m *** flow velocity was measured with electrolyte trace method,under pulse boundary *** leading edge and accurate flow velocities were used to determine the correction coefficient to convert the former to the *** showed that the correction coefficient on frozen soil slope was 0.81 with a coefficient of determination(R2.of *** correction coefficient on non-frozen soil slope was 0.79 with R2.of 0.98.A coefficient of 0.8 was applicable to both soil surface *** accurate velocities on the four frozen black soil slopes were approximately 30%,54%,71%,and 91%higher than those on non-frozen soil *** contrast,the leading edge flow velocities on the frozen soil slopes were 2.%,54%,67%,and 84%higher than those on non-frozen soil *** flow velocities on frozen soil slopes increased with flow rate at all four slopes,but they increased from 5 to 15°before getting ***,rill flow velocity can be effectively measured with leading edge method by multiplying the leading edge velocity with a correction coefficient of *** study provides a strategy to measure rill flow velocity for studies on soil erosion mechanisms.

关键词： Flow velocity Leading edge method frozen/non-frozen soil

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气候变化下多年冻土融水对青藏高原径流影响评估（英文）

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Science Bulletin 2023年第11期 1105-1108页

作者：王泰华杨大文杨雨亭郑冠恒金会军李新姚檀栋程国栋 state key {2. of Hydroscience and engineering Department of Hydraulic Engineering Tsinghua University Institute of Cold Region Science and engineering School of Civil Engineering Northeast Forestry University state key {2. of frozen Soil engineering Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences National Tibetan Plateau Data Center Institute of Tibetan Plateau Research Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of Sciences Institute of Urban Study Shanghai Normal University

青藏高原约40%的面积分布有多年冻土,相比冰川积雪融水得到的广泛关注,冻土融水对径流的影响仍有待评估.本研究基于耦合冰冻圈过程的分布式水文模型GBEHM(Geomorphology-based Ecohydrological Model),在区域尺度量化了多年冻土融水对...

青藏高原约40%的面积分布有多年冻土,相比冰川积雪融水得到的广泛关注,冻土融水对径流的影响仍有待评估.本研究基于耦合冰冻圈过程的分布式水文模型GBEHM(Geomorphology-based Ecohydrological Model),在区域尺度量化了多年冻土融水对径流的影响.研究结果表明:(1)过去40年间,青藏高原多年冻土面积下降13.9%,地下冰储量减少约401.1 Gt,约为同期冰川储量减少量的2.;(2.多年冻土融水对全青藏高原总径流贡献相对较小(约0.5%),但在某些区域(如黄河上游、长江上游)和高程范围(如河西走廊4000m高程附近),地下冰融水对径流的贡献超过冰川融水贡献,其影响不可忽略;(3)气候变化背景下,地下冰融水径流在未来不可持续,澜沧江、怒江等区域历史阶段已经达到峰值,而对全青藏高原,融水径流拐点预计将在2.世纪2.年代(SSP1-2.6)、50年代(SSP2.4.5)或90年代(SSP5-8.5)达到.

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Diverse viromes in polar regions: A retrospective study of metagenomic data from Antarctic animal feces and Arctic frozen soil in 2.12.2.14

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Virologica Sinica 2022年第6期37卷 883-893页

作者： Jun Wang Jian Xiao Zheng Zhu Siyuan Wang Lei Zhang Zhaojun Fan Yali Deng Zhihong Hu Fang Peng Shu Shen Fei Deng state key {2. of Virology and National Virus Resource Center Wuhan Institute of VirologyChinese Academy of SciencesWuhan 430071China Xinjiang key laboratory of Biological Resources and Genetic {2. College of Life Science and TechnologyXinjiang UniversityUrumqi830046China China Center for Type Culture Collection(CCTCC) College of Life SciencesWuhan UniversityWuhan430072China Natisonal Emerging Infectious Diseases Laboratories Boston UniversityBostonMA 02118United States Department of Biochemistry Boston University School of MedicineBostonMA 02118United States

Antarctica and the Arctic are the coldest places, containing a high diversity of microorganisms, including viruses,which are important components of polar ecosystems. However, owing to the difficulties in obtaining access to animal and environmental samples, the current knowledge of viromes in polar regions is still limited. To better understand polar viromes, this study performed a retrospective analysis using metagenomic sequencing data of animal feces from Antarctica and frozen soil from the Arctic collected during 2.12.2.14. The results reveal diverse communities of DNA and RNA viruses from at least 2. families from Antarctic animal feces and 16families from Arctic soils. Although the viral communities from Antarctica and the Arctic show a large diversity,they have genetic similarities with known viruses from different ecosystems and organisms with similar viral proteins. Phylogenetic analysis of Microviridae, Parvoviridae, and Larvidaviridae was further performed, and complete genomic sequences of two novel circular replication-associated protein(rep)-encoding single-stranded(CRESS) DNA viruses closely related to Circoviridae were identified. These results reveal the high diversity,complexity, and novelty of viral communities from polar regions, and suggested the genetic similarity and functional correlations of viromes between the Antarctica and Arctic. Variations in viral families in Arctic soils,Arctic freshwater, and Antarctic soils are discussed. These findings improve our understanding of polar viromes and suggest the importance of performing follow-up in-depth investigations of animal and environmental samples from Antarctica and the Arctic, which would reveal the substantial role of these viruses in the global viral community.

关键词： Arctic soil Antarctica animal feces Metagenomics Virus diversity

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Automatic Identifcation of Thaw Slumps Based on Neural Network Methods and Thaw Slumping Susceptibility

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International Journal of Disaster Risk Science 2023年第4期14卷 539-548页

作者： Huarui Zhang Huini Wang Jun Zhang Jing Luo Guoan Yin School of Civil engineering and Architecture Wuhan Institute of TechnologyWuhan 430074China state key {2. of frozen Soil engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

Thaw slumping is a periglacial process that occurs on slopes in cold environments,where the ground becomes unstable and the surface slides downhill due to saturation with water during *** this study,GaoFen-1 remote sensing and fused multi-source feature data were used to automatically map thaw slumping landforms in the Beilu River Basin of the Qinghai–Tibet *** bi-directional cascade network structure was used to extract edges at diferent scales,where an individual layer was supervised by labeled edges at its specifc scale,rather than directly applying the same supervision to all convolutional neural network ***,we conducted a 5-year multi-scale feature analysis of small baseline subset interferometric synthetic aperture radar deformation,normalized diference vegetation index,and slope,among other *** study analyzed the performance and accuracy of three methods based on edge object supervised learning and three preconfgured neural networks,ResNet101,VGG16,and *** verifcation using site surveys and multi-data fusion results,we obtained the best ResNet101 model score of intersection over union of 0.85(overall accuracy of 84.59%).The value of intersection over union of the VGG and ResNet152.are 0.569 and 0.773,*** work provides a new insight for the potential feasibility of applying the designed edge detection method to map diverse thaw slumping landforms in larger areas with high-resolution images.

关键词： Bi-directional cascade network Remote sensing SBAS-InSAR Thaw slumping

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A new valence bond based energy decomposition analysis scheme

A new valence bond based energy decomposition analysis schem...

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第十三届全国量子化学会议

作者： Yang Zhang Sifeng Chen Peifeng Su Wei Wu The state key {2. of Physical Chemistry of Solid Surfaces Fujian Provincial Key Laboratory of Theoretical and Computational Chemistryand College of Chemistry and Chemical EngineeringXiamen University

Valence bond（VB） theory,[1] which is one of the general theoretical approaches for chemical bonding, has been employed to the analysis of molecular interaction recently. [2.3] In this work, a new energy decomposition analysis（EDA） scheme is proposed with VB wave-function. The total interaction energy is decomposed into frozen,charge transfer, polarization terms with definitions of each based upon several intermediate VB reference states. Using this scheme, a new insight for cation-π interaction is explored.

关键词： Chemical bond VB theory Energy decomposition analysis

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Frost heave control of fine round gravel fillings in deep seasonal frozen regions

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Research in Cold and Arid Regions 2013年第4期5卷 425-432页

作者： ZuRun Yue TianLiang Wang Chao Ma TieCheng Sun Graduate School Shijiazhuang Tiedao University School of Civil engineering Shijiazhuang Tiedao University key laboratory of Roads and Railway {2. Safety Control of Ministry of Education Shijiazhuang Tiedao University

Fine round gravel soil is widely employed in the subgrade of high and thawing. The lower the fines content in fine round gravel soil, but compaction difficulty increases. This study is to obtain the speed railways in cold regions to prevent frost heaving the smaller the quantities of frost heaving and thawing, optimum fines content and limited frost heaving and thawing. The fine round gravel soil filling （FRGSF） used in the Harbin-Qiqihaer Passenger Dedicated Line is taken as the study object. Influence of fines content on optimum water content, maximum dry density and frost heaving properties of FRGSF were studied by means of compaction and frost heaving tests. Results show that the maximum dry density of the FRGSF increases first and then decreases with an increase of fines content, namely there is an optimum fines content for easy compaction. The method of surface-vibratory instrument is fit for coarse-grained soils, and wet state of coarse-grained soil is in favor of compaction. Considering the relationship of fines content with maximum dry density and the frost heaving ratio of FRGSF, the fines content should be limited to within the range of 9%-10%, so that the frost heaving ratio is less than 1%, and the FRGSF is easily compacted. Water supply is proved to be an important factor influencing the amount of frost heaving of FRGSF. We also conclude that in the field, it is imperative to control waterproofing and drainage measures.

关键词： cold regions fine round gravel soil filling frost heaving ratio compaction properties

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Experimental study of dynamic resilient modulus of subgrade soils under coupling of freeze–thaw cycles and dynamic load

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Journal of Central South University 2020年第7期27卷 2043-2053页

作者： ZHAO Yang LU Zheng YAO Hai-lin GU Fan DUAN Ya-hui state key {2. of Geomechanics and Geotechnical engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China Hubei key laboratory of Geo-Environmental {2. Wuhan 430071China National engineering laboratory of Highway Maintenance Technology Changsha University of Science&TechnologyChangsha 410114China National Center for Asphalt Technology Auburn UniversityAuburn 36830USA School of Urban Construction Wuchang University of TechnologyWuhan 430023China

Although the dynamic properties of subgrade soils in seasonally frozen areas have already been studied, few researchers have considered the influence of shallow groundwater during the freeze–thaw(F–T) cycles. So a multifunctional F–T cycle system was developed to imitate the groundwater recharge in the subgrade during the freezing process and a large number of dynamic triaxial experiments were conducted after the F–T cycles. Some significant factors including the F–T cycle number, compaction degree, confining pressure, cyclic deviator stress, loading frequency, and water content were investigated for the resilient modulus of soils. The experimental results indicated that the dynamic resilient modulus of the subgrade was negatively correlated with the cyclic deviator stress, F–T cycle number, and initial water content, whereas the degree of compaction, confining pressure, and loading frequency could enhance the resilient modulus. Furthermore, a modified model considering the F–T cycle number and stress state was established to predict the dynamic resilient modulus. The calculated results of this modified model were very close to the experimental results. Consequently, calculation of the resilient modulus for F–T cycles considering the dynamic load was appropriate. This study provides reference for research focusing on F–T cycles with groundwater supply and the dynamic resilient moduli of subgrade soils in seasonally frozen areas.

关键词： dynamic resilient modulus freeze–thaw cycles dynamic load dynamic triaxial test prediction model

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Shear properties of thawed natural permafrost by bender elements

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Research in Cold and Arid Regions 2017年第4期9卷 343-351页

作者： Feng Zhang ZhaoHui (Joey) Yang JiaHui Wang HaiPeng Li Benjamin Still School of Transportation Science and engineering Harbin Institute of Technology Harbin Heilongjiang 150090China College of engineering University of Alaska Anchorage Anchorage Alaska 99508 USA School of Civil engineering Harbin Institute of Technology Harbin Heilongjiang 150090 China state key {2. of Geo-mechanics and Deep Underground engineering China University of Mining and Technology Xuzhou Jiangsu 21116 China

Thawed permafrost could cause a serious stability problem for foundations and oil-wells in cold regions. A non-damage testing procedure, employing the Bender Element Method, was used for permafrost samples collected from a continuous frozen core obtained from the North Slope of Alaska, USA. The wave velocity and modulus of thawed permafrost were investigated on various isotropic confining pressure from 0 kPa to 400 kPa per 100 kPa. The received shear wave propagation was recorded, and the elastic wave theory was used to calculate shear modulus. Finally, the shear modulus affected by confining pressure, water content and dry density were analyzed and discussed, and a regression formulation of shear modulus based on the Janbu Model for thawed silty and sandy permafrost were proposed and validation.

关键词： shear velocity shear modulus thawed natural permafrost bender element

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The role of bone marrow-derived cells in the origin of liver cancer revealed by single-cell sequencing

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Cancer Biology & Medicine 2020年第1期17卷 142-153页

作者： Lu Chen Xianfu Yi Piao Guo Hua Guo Ziye Chen Chunyu Hou Lisha Qi Yongrong Wang Chengwen Li Peng Liu Yucun Liu Yuanfu Xu Ning Zhang The concrete information of affiliations should be presented for instanceDepartment of Tianjin Medical University Cancer Institute and HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjin's Clinical Research Center for CancerTianjin 300070China School of Biomedical engineering and Technology Tianjin Medical UniversityTianjin 300070China The Center for Translational Cancer Research Peking University First HospitalBeijing 100034China state key {2. of Experimental Hematology National Clinical Research Center for Blood DiseasesInstitute of Hematology&Blood Diseases HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeTianjin 300020China CAMS key laboratory for Prevention and Control of Hematological Disease Treatment Related Infection Tianjin 300020China Cytogenetics laboratory Institute of Hematology and Blood Diseases HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeTianjin 300020China

Objective:Epithelial cancers often originate from progenitor cells,while the origin of hepatocellular carcinoma(HCC)is still ***,one of the deadliest cancers,is closely linked with liver injuries and chronic inflammation,which trigger massive infiltration of bone marrow-derived cells(BMDCs)during liver ***:To address the possible roles of BMDCs in HCC origination,we established a diethylnitrosamine(DEN)-induced HCC model in bone marrow transplanted *** and frozen tissue immunofluorescence were used to verify DENinduced HCC in the pathology of the *** cellular origin of DEN-induced HCC was further studied by single cell sequencing,single-cell nested PCR,and immunofluorescence-fluorescence in situ ***:Studies by using single cell sequencing and biochemical analysis revealed that HCC cells in these mice were coming from donor mice BMDCs,and not from recipient ***,the copy numbers of mouse orthologs of several HCC-related genes previously reported in human HCC were also altered in our mouse ***-induced HCCs exhibited a similar histological phenotype and genomic profile as human ***:These results suggested that BMDCs are an important origin of HCC,which provide important clues to HCC prevention,detection,and treatments.

关键词： Hepatocellular carcinoma bone marrow-derived cells(BMDCs) origination genome sequencing copy number alteration

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Freeze–thaw effects on erosion process in loess slope under simulated rainfall

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Journal of Arid Land 2020年第6期12卷 937-949页

作者： SU Yuanyi LI Peng REN Zongping XIAO Lie ZHANG Hui state key {2. of Eco-hydraulics in Northwest Arid Region of China Xi'an University of TechnologyXi'an 710048China key laboratory of National Forestry Administration on Ecological Hydrology and Disaster Prevention in Arid Regions Xi'an 710048China China JIKAN Research Institute of engineering Investigations and Design Co.Ltd. Xi'an 710048China

Seasonal freeze–thaw processes have led to severe soil erosion in the middle and high *** area affected by freeze–thaw erosion in China exceeds 13%of the national *** understanding the effect of freeze–thaw on erosion process is of great significance for soil and water conservation as well as for ecological *** this study,we designed simulated rainfall experiments to investigate soil erosion processes under two soil conditions,unfrozen slope(UFS)and frozen slope(FS),and three rainfall intensities of 0.6,0.9 and 1.2.mm/*** results showed that the initial runoff time of FS occurred much earlier than that of the *** the same rainfall intensity,the runoff of FS is 1.17–1.2. times that of UFS;and the sediment yield of FS is 6.48–10.49 times that of *** increasing rainfall time,rills were produced on the *** the appearance of the rills,the sediment yield on the FS accounts for 74%–86%of the total sediment *** erosion was the main reason for the increase in soil erosion rate on FS,and the reduction in water percolation resulting from frozen layers was one of the important factors leading to the advancement of rills on slope.A linear relationship existed between the cumulative runoff and the sediment yield of UFS and FS(R2.0.97,PFS0.6(72.30μm)>UFS1.2.72.2.μm)>substrate(71.2.μm)>FS1.2.71.06μm)>FS0.9(70.72.m).During the early stage of the rainfall,the MWD of the FS was relatively ***,during the middle to late rainfall,the particle composition gradually approached that of the soil *** different rainfall intensities,the mean soil erodibility(MK)of the FS was 7.2. times that of the *** ratio of the mean regression coefficient C2.MC2.between FS and UFS was roughly correspondent with ***,the parameter C2.can be used to evaluate soil erodibility after the appearance of the ***

关键词： unfrozen slope(UFS) frozen slope(FS) simulated rainfall soil size selectivity soil erodibility loess hilly region

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