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Using ^(137)Cs Tracing Methods to Estimate Soil Redistribution Rates and to Construct a Sediment Budget for a Small Agricultural Catchment in the Three Gorges Reservoir Region,China

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Journal of mountain Science 2013年第3期10卷 428-436页

作者： JU Li WEN An-bang LONG Yi YAN Dong-chun GUO Jin Key Laboratory of mountain Surface Processes and Ecological Regulation Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences University of Chinese Academy of Sciences

Soil erosion and associated off-site sedimentation are threatening the sustainable use of the Three Gorges Dam. To initiate management intervention to reduce sediment yields, there is an increasing need for reliable information on soil erosion in the Three Gorges Reservoir Region （TGRR）. The purpose of this study is to use 137Cs tracing methods to construct a sediment budget for a small agricultural catchment in the TGRR. Cores were taken from a pond and from paddy fields, for laTCs measurements. The results show that the average sedimentation rate in the pond since 1963 is 1.50 g cm-2 yr-1 and the corresponding amount of sediment deposited is 1,553 t. The surface erosion rate for the sloping cultivated lands and the sedimentation rate in the paddy fields were estimated to be 3,770 t km-2 yr-1 and 2,600 t km-2 yr^1 respectively. Based on the estimated erosion and deposition rates, and the area of each unit, the post 197o sediment budget for the catchment has been constructed. A sediment delivery ratio of 0.5 has been estimated for the past 42 years. The data indicate that the sloping cultivated lands are the primary sediment source areas, and that the paddy fields are deposition zones. The typical land use pattern （with the upper parts characterized by sloping cultivated land and the lower parts by paddy fields） plays an important role in reducing sediment yield from agricultural catchments in the TGRR. A 137Cs profile for the sediment deposited in a pond is shownto provide an effective means of estimating the land surface erosion rate in the upstream catchment.

关键词： Pond deposition Soil erosion rate Sediment budget 137Cs Sediment delivery ratio Three Gorges Reservoir Region

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EXPERIMENTAL INVESTIGATION OF THE FAILURE OF CASCADE LANDSLIDE DAMS

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Journal of Hydrodynamics 2012年第3期24卷 430-441页

作者： NIU Zhi-pan XU Wei-lin LI Nai-wen XUE Yang CHEN Hua-yong State key Laboratory of Hydraulics and mountain River Engineering Sichuan University Chengdu 610065China Key Laboratory-of mountain Hazards and Land Surface Processes and institute of mountain Hazards andEnvironment Chinese Academy of Sciences Chengdu 610041 China

This paper presents results of model tests for the landslide dam failure of a single dam and cascade dams in a sloping channel. The dams were designed to be regular trapezoid with fine sand. A new measuring method named the labeled line locating method was used to digitalize the captured instantaneous pictures. Under two different inflow discharges, the morphological evolution and the flow patterns during one dam failure and the failure of cascade dams were investigated. The results indicate that when the inflow discharge is large, the deformation pattern of the downstream dam is similar to that of the upstream dam, and both dams are characterized with the overtopping scour throughout the dam failure process. When the inflow discharge is small, the upstream dam is scoured mainly through a sluice slot formed by the longitudinal incision, and the downstream dam is characterized with the overtopping scour. The data set presented in this paper can be used for the validation of numerical models and provide a reference for the flood risk management of cascade landslide dams.

关键词： labeled lines locating method inflow discharge cascade landslide dam failure overtopping sloping flume

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Deciphering the role of mtH2O2 in hepatic ischemia-reperfusion injury mechanisms with low-background super-resolution fluorogenic probe

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Science China Chemistry 2025年第01期 297-307页

作者： Bin Fang Limin Wang Haoqin Li Jiaxin Zhang Yang Ding Pan Pan Li Bo Peng Hua Bai Lin Li Frontiers Science Center for Flexible Electronics Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials &Engineering Northwestern Polytechnical University institute of Flexible Electronics (IFE Future Technologies) Xiamen University

Hepatic ischemia-reperfusion injury（HIRI） is characterized by mitochondrial dysfunction and oxidative stress. Monitoring mitochondrial hydrogen peroxide（mtH2O2） levels in real-time through super-resolution imaging is crucial for elucidating its distribution in live cells and its mechanism of action during HIRI. However, low-background fluorogenic probes have been overlooked in the context of super-resolution imaging. In this study, we developed a low-background fluorogenic probe（MitoWG） with the potential for super-resolution morphology-correlated mitochondrial identification to track the fluctuates of mtH2O2in HIRI. Activation of the desirable fluorescence properties of the probe by mtH2O2was confirmed using structural illumination microscopy（SIM）, enabling high-quality mitochondrial imaging with exceptional specificity and *** in mtH2O2levels were successfully observed in both cellular and rat models of HIRI. Furthermore, we associated the decline in mitochondrial redox homeostasis with accelerated mtH2O2production during HIRI, which triggered mitophagy deficiency and led to cell death. In conclusion, Mito-WG possesses excellent photophysical and low-background properties for SIM imaging, making it a promising tool for mtH2O2tracking in HIRI research and clinical diagnosis.

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Group-spawning and Simultanous Polyandry of a Stream-dwelling Frog Feirana kangxianensis

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Asian Herpetological Research 2014年第4期5卷 240-244页

作者： Jie WANG Feng XIE Gang WANG Jianping JIANG Chengdu institute of biology Chinese Academy of Sciences Key Laboratory of mountain Ecological Restoration and Bioresource Utilization CAS and Ecological Restoration and Biodiversity Conservation

Here we provide an example of simultaneous polyandry based on genetic evidence in Feirana kangxianensis. This stream-dwelling species occurs only in Kangxian County, southern Gansu Province, where it is sympatric with its sibling species E quadranus. During the breeding season the sex ratio of E kangxianensis was marginally female- biased （44~：59~） and the encounter rate in a relatively pristine habitat was significantly higher than that in heavily quarried habitats （9.6 ± 4.8 indiv./km vs. 3.2 ± 2.5 indiv./km）. Three egg masses containing an average of 698 eggs were deposited on the underside of one or two adjacent flat rocks, 6.0-10.0 cm under the water surface and 1.0-3.5 cm above the streambed. Using Bayesian sibship clustering of nine polymorphic microsatellite genotypes, two females were detected as group-spawning in one oviposition site, with three males fertilizing each female＇s eggs simultaneously. We also discuss the conservation requirements of this range-restricted species and the evolutionary implication of its unusual reproductive strategy.

关键词： group-spawning oviposition site sex ratio simultaneous polyandry habitat conservation

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Livelihood Diversification as an Adaptation Approach to Change in the Pastoral Hindu-Kush Himalayan Region

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Journal of mountain Science 2014年第5期11卷 1342-1355页

作者： WU Ning Muhammad ISMAIL Srijana JOSHI YI Shao-liang Ritu Meher SHRESTHA Abdul Wahid JASRA International Centre for Integrated mountain Development G.P.O Box 3226 Kathmandu Nepal Key Laboratory of mountain Ecological Restoration and Bioresource Utilization & Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of Biology Chinese Academy of Sciences

Migratory livestock raising has been one of the most important livelihood options for people residing in high mountain areas and has made a significant contribution to the economy of the Hindu Kush Himalayan(HKH) region, both in terms of supporting households and in export earnings. However, in recent decades, changes in the socioeconomic situation and increasing climate variability have led to a need to enhance adaptation by building the resilience of local socio-ecological systems, including economic diversification and sustainable management of natural resources. Based on semistructured interviews with pastoral communities in six countries within the pastoral HKH region, this paper discusses the situation, trends and driving forces behind the diversification of pastoral livelihood. For internal diversification the study highlights the need for enhancement of pastoral livelihoods through value-adding activities in the pastoral sectors. For external diversification changes on policy changes are needed to support free out-migration, market exploitation, and multiple resource use. Finally the paper highlights the role of education in determining household adaptation strategies in the face of various socio-ecological pressures and recommends integrating innovative and indigenous knowledge to develop appropriate methods for risk management and resource management in the pastoral HKH region.

关键词： Adaptive capacity Diversification Livelihoods Pastoralism Himalaya

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Influence of inflow discharge and bed erodibility on outburst flood of landslide dam

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Journal of mountain Science 2019年第4期16卷 778-792页

作者： ZHOU Ming-jun ZHOU Gordon G.D. CUI Kahlil Fredrick E. SONG Dong-ri LU Xue-qiang Key Laboratory of mountain Hazards and Earth Surface Process/institute of mountain Hazards and Environment Chinese Academy of Sciences University of Chinese Academy of Sciences

Accurate prediction of the hydrographs of outburst floods induced by landslide dam overtopping failure is necessary for hazard prevention and mitigation. In this study, flume model tests on the breaching of landslide dams were conducted. Unconsolidated soil materials with wide grain size distributions were used to construct the dam. The effects of different upstream inflow discharges and downstream bed soil erosion on the outburst peak discharge were investigated. Experimental results reveal that the whole hydrodynamic process of landslide dam breaching can be divided into three stages as defined by clear inflection points and peak discharges. The larger the inflow discharge, the shorter the time it takes to reach the peak discharge, and the larger the outburst flood peak discharge. The scale of the outburst floods was found to be amplified by the presence of an erodible bed located downstream of the landslide dam. This amplification decreases with the increase of upstream inflow. In addition, the results show that the existence of an erodible bed increases the density of the outburst flow, increasing its probability of transforming from a sediment flow to a debris flow.

关键词： Landslide dam Inflow discharge Erodible bed Outburst flood

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Mechanism of Downcutting Erosion of Debris Flow over a Movable Bed

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Journal of mountain Science 2015年第1期12卷 243-250页

作者： Pan Hua-li Huang Jiang-cheng Ou Guo-qiang Key Laboratory of mountain Hazards and Earth Surface Process Institute of Mountain Hazards and Environment CAS Asian International Rivers Center Yunnan University

The phenomenon of debris flow is intermediate between mass movement and solid transport. Flows can be sudden, severe and destructive. Understanding debris flow erosion processes is the key to providing geomorphic explanations, but progress has been limited because the physical-mechanical properties, movement laws and erosion characteristics are different from those of sediment-laden flow. Using infinite slope theory, this research examines the process and mechanism of downcutting erosion over a moveable bed in a viscous debris flow gully. It focuses specifically on the scour depth and the critical slope for viscous debris flow,and formulas for both calculations are *** scour depth and the critical conditions of downcutting erosion are related to debris flow properties(sand volume concentration and flow depth) and gully properties(longitudinal slope,viscous and internal friction angle of gully materials,and coefficient of kinetic friction). In addition, a series of flume experiments was carried out to characterize the scouring process of debris flows with different properties. The calculated values agreed well with the experimental data. These theoretical formulas are reasonable, and using infinite slope theory to analyze down cutting erosion from viscous debris flow is feasible.

关键词： Debris flow Down cutting erosion Infinite slope theory Critical conditions Flumeexperiments

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ATPF–a dedicated proton therapy facility

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Chinese Physics C 2010年第3期34卷 383-388页

作者：方守贤关遐令唐靖宇陈沅邓昌东董海义傅世年焦毅舒航欧阳华甫邱静石才土孙虹韦杰杨梅张旌 institute of high Energy Physics CAS

A proton therapy facility based on a linac injector and a slow-cycling synchrotron is proposed. To obtain good treatments for different cancer types, both the spot scanning method and the double-scattering method are adopted in the facility, whereas the nozzles include both gantry and fixed beam types. The proton accelerator chain includes a synchrotron of 250 MeV in maximum energy, an injector of 7 MeV consisting of an RFQ and a DTL linac, with a repetition rate of 0.5 Hz. The slow extraction using the third-order resonance and together with the RFKO method is considered to be a good method to obtain a stable and more-or-less homogenous beam spill. To benefit the spot scanning 200 between 60 MeV and 230 MeV. A new method method, the extraction energy can be as many as about - the emittance balancing technique of using a solenoid or a quadrupole rotator is proposed to solve the problem of unequal emittance in the two transverse planes with a beam slowly extracted from a synchrotron. The facility has been designed to keep the potential to be upgraded to include the carbon therapy in the future.

关键词： hadron therapy irradiation method slow extraction emittance balancing gantry

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Kinematics of τ two-body decay near τ threshold at BESⅢ

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Chinese Physics C 2010年第11期34卷 1671-1679页

作者：莫晓虎 institute of high Energy Physics CAS

The kinematic properties of two-body decay near τ threshold are studied according to the special capacity of the BEPC accelerator and the BESⅢ *** presented are the transformations of energy and momentum of hadronic particles between different reference frames,and the corresponding distributions.A brand new method is proposed to obtain the energy spread of the accelerator by fitting the energy distribution of hadron from τ semi-leptonic decays.

关键词： kinematics τ threshold energy distribution energy spread

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Study of the design of CSNS MEBT

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Chinese Physics C 2009年第7期33卷 583-589页

作者：欧阳华甫刘华昌傅世年 institute of high Energy Physics CAS

The design of CSNS MEBT has two objectives：（1） to match the beam both in the transversal direction and the longitudinal direction from RFQ into DTL;（2） to further chop the beam into the required time structure asked by RCS. It is very diffcult and critical to control well the emittance growth and in the meantime to match and chop the beam. Firstly,the optical design is done and optimized,and the multi-particle simulations show that the maximum emittance growth is successfully controlled within 14%. Secondly,based on the different beam envelopes obtained by TRACE-3D and PARMELA,the least deflecting angle of the chopper is determined by TRACE-3D. At last,the field of steering magnet is determined through simulations.

关键词： MEBT chopper match beam envelope emittance growh central orbit

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