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Soil Erosion and Its Basic Characteristics at Karst Rocky-desertified Land Consolidation Area: A Case Study at Muzhe Village of Xichou County in Southeast Yunnan, China

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Journal of Mountain Science 2010年第1期7卷 55-72页

作者： yang zisheng yang longfei zhang bosheng Institute of Land & Resources and Sustainable Development Yunnan University of Finance and Economics Kunming650221 China

Xichou County of Wenshan Zhuang and Miao Autonomous Prefecture in southeast Yunnan is one of the karst mountainous areas in southwest China showing typical rock desertification. During this study, we set up three soil erosion contrast test spots at Muzhe Village, Benggu Township, Xichou County, which was the birthplace of the Xichou rock-desertified land consolidation mode. The three spots included the terrace land spot （already consolidated land）, sloping land spot （unconsolidated sloping land under rock desertification）, and standard runoff spot （bare land spot）. In 2007, a whole-year complete observation was conducted during the rainy season and ＂rainfall-erosion＂ data were obtained for 32 times. Our analysis showed that during the entire observation period, the number of the rainfalls that led to soil erosion accounted for 34.04% of the number of all rainfalls and the amount of the rainfalls that led to soil erosion accounted for 84.17% of the total amount of all rainfalls. The average erosive rainfall standard in the three test spots was 11.0mm, slightly higher than the lO mm standard that has been adopted all over China, but lower than the 12.7 mm standard of the US and the 13.0 mm standard of Japan. According to single-factor analysis, the soil loss in the sloping land spot （L2） and that in the bare land spot （L3） are correlated to certain extent to manyother factors, including the single precipitation （P）, rainfall intensity during the maximum ten minutes （Lo）, rainfall intensity during the maximum 20 minutes （I2o）, rainfall intensity during the maximum 30 minutes （I30）, rainfall intensity during the maximum 40 minutes （I4o）, and rainfall intensity during the maximum 6o minutes （I60）. Among these factors, they are of the highest relativity with I6o. According to double-factor analysis, both L2 and L3 are of good relativity with P and I60. According to multi-factor analysis, L2 and L3 are also of good relativity with seven rainfall indexes, namely, P, Ia （ave

关键词： karst mountainous area rockdesertification land consolidation soil erosion testspot Xichou County

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Initiation and Kinematic Process of Debris Flow with the Existence of Terraced Fields at the Sources

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Journal of Earth Science 2024年第5期35卷 1613-1625页

作者： Liang yang yang Wang Kang Liao longfei zhang Aiyun Chen Juan Du Faculty of Engineering China University of Geosciences China Railway Siyuan Survey and Design Group Co. LTD.

A debris flow, with terraced fields as the source area, broke out on June 25th, 2018 in the Xiaotuga area of Yunnan Province, China, and this kind of debris flow is rarely recorded. Two purposes in this study:(1) the influence of flow drag force on slope stability;(2) back-analyze the movement process of debris flow. First, the geological background and movement of this debris flow were described based on a field investigation. Then, drag force, calculated by the laminar flow theory, is added to the slope stability calculation model, which elaborates the initiation process of this disaster. Moreover, dynamic simulation software(DAN3D) was used to simulate the kinematic process of the debris flow with a variety of combination models. The study shows that the terrace area can quickly produce surface runoff and create a drag force under rainfall conditions, which is the essential reason for the initiation of debris flow. In addition, the use of the FVV(Frictional-Voellmy-Voellmy) model is found to provide the best performance in simulating this type of debris flow, which reveals that it lasts approximately 200 s and that the maximum velocity is 12 m/s.

关键词： debris flow initiation process kinematic process terraced fields engineering geology

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Measurement of 2p-3d absorption in a hot molybdenum plasma

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Matter and Radiation at Extremes 2024年第4期9卷 68-79页

作者： Gang Xiong Bo Qing Zhiyu zhang longfei Jing yang Zhao Minxi Wei Yimeng yang Lifei Hou Chengwu Huang Tuo Zhu Tianming Song Min Lv Yan Zhao Yuxue zhang Guohong yang Zeqing Wu Jun Yan Yaming Zou Jiyan zhang Jiamin yang Shanghai EBIT Laboratory and Key Laboratory of Nuclear Physics and Ion-Beam Application(MOE)Institute of ModernPhysicsFudan UniversityShanghai 200433China Laser Fusion Research Center China Academy of Engineering PhysicsMianyang 621900China Institute of Applied Physics and Computational Mathematics Beijing 100088China

We present measurements of the 2p-3d transition opacity of a hot molybdenum-scandium sample with nearly half-vacant molybdenum M-shell configurations.A plastic-tamped molybdenum-scandium foil sample is radiatively heated to high temperature in a compact D-shaped gold Hohlraum driven by∼30 kJ laser energy at the SG-100 kJ laser facility.X rays transmitted through the molybdenum and scandium plasmas are diffracted by crystals and finally recorded by image *** electron temperatures in the sample in particular spatial and temporal zones are determined by the K-shell absorption of the scandium plasma.A combination of the IRAD3D view factor code and the MULTI hydrodynamic code is used to simulate the spatial distribution and temporal behavior of the sample temperature and *** inferred temperature in the molybdenum plasma reaches a average of 138±11 eV.A detailed configuration-accounting calculation of the n=2–3 transition absorption of the molybdenum plasma is compared with experimental measurements and quite good agreement is *** present measurements provide an opportunity to test opacity models for complicated M-shell configurations.

关键词： molybdenum absorption configuration

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Comparative analysis of DNA-SIP and magnetic-nanoparticle mediated isolation (MMI) on unraveling dimethoate degraders

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Frontiers of Environmental Science & Engineering 2024年第1期18卷 59-69页

作者： Luning Lian Yi Xing Dayi zhang longfei Jiang Mengke Song Bo Jiang School of Energy and Environmental Engineering University of Science&Technology BeijingBeijing 100083China Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants University of Science&Technology BeijingBeijing 100083China National Environmental and Energy Science and Technology International Cooperation Base University of Science&Technology BeijingBeijing 100083China College of New Energy and Environment Jilin UniversityChangchun 130021China Guangzhou Institute of Geochemistry Chinese Academy of SciencesGuangzhou 510640China College of Natural Resources and Environment South China Agricultural UniversityGuangzhou 510642China National Engineering Laboratory for Site Remediation Technologies Beijing 100015China

Microorganisms are crucial in the bioremediation of organophosphorus pesticides. However, most functional microorganisms (> 99%) are yet to be cultivated. This study applied two cultivation-independent approaches, DNA-SIP and magnetic-nanoparticle mediated isolation (MMI), to identify the functional microorganisms in degrading dimethoate in agricultural soils. MMI identified five dimethoate degraders: Pseudomonas, Bacillus, Ramlibacter, Arthrobacter, and Rhodococcus, whereas DNA-SIP identified three dimethoate degraders: Ramlibacter, Arthrobacter, and Rhodococcus. Also, MMI showed higher resolution than DNA-SIP in identifying functional microorganisms. Two organic phosphohydrolase (OPH) genes: ophC2 and ophB, were involved in dimethoate metabolism, as revealed by DNA-SIP and MMI. The degradation products of dimethoate include omethoate, O,O,S-trimethyl thiophosphorothioate, N-methyl-2-sulfanylacetamide, O,O-diethyl S-hydrogen phosphorodithioate, O,O,O-trimethyl thiophosphate, O,O,S-trimethyl thiophosphorodithioate, and O,O,O-trimethyl phosphoric. This study emphasizes the feasibility of using SIP and MMI to explore the functional dimethoate degraders, expanding our knowledge of microbial resources with cultivation-independent approaches.

关键词： Stable isotope probing(SIP) Magnetic-nanoparticle mediated isolation(MMI) Dimethoate Biodegradation Cultivation-independent approach

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A novel high-Cr CoNi-based superalloy with superior high-temperature microstructural stability, oxidation resistance and mechanical properties

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1373-1381页

作者： Xiaorui zhang Min Zou Song Lu longfei Li Xiaoli Zhuang Qiang Feng Beijing Advanced Innovation Center for Materials Genome Engineering State Key Laboratory for Advanced MetalsUniversity of Science and Technology BeijingBeijing 100083China

A novel multicomponent high-Cr CoNi-based superalloy with superior comprehensive performance was prepared,and the evaluation of its high-temperature microstructural stability,oxidation resistance,and mechanical properties was conducted mainly using its cast polycrystalline *** results disclosed that the morphology of theγ′phase remained stable,and the coarsening rate was slow during the long-term aging at 900–1000℃.The activation energy forγ′precipitate coarsening of alloy 9CoNi-Cr was(402±51)kJ/mol,which is higher compared with those of CMSX-4 and some other Ni-based and Co-based ***,there was no indica-tion of the formation of topologically close-packed phases during this *** these factors demonstrated the superior microstructural stability of the *** mass gain of alloy 9CoNi-Cr was 0.6 mg/cm^(2) after oxidation at 1000℃ for 100 h,and the oxidation resistance was comparable to advanced Ni-based superalloys CMSX-4,which can be attributed to the formation of a continuous Al_(2)O_(3) protective ***,the compressive yield strength of this cast polycrystalline alloy at high temperatures is clearly higher than that of the conventional Ni-based cast superalloy and the compressive minimum creep rate at 950℃ is comparable to that of the conventional Ni-based cast superalloy,demonstrating the alloy’s good mechanical properties at high *** is partially because high Cr is bene-ficial in improving theγandγ′phase strengths of alloy 9CoNi-Cr.

关键词： CoNi-based superalloys microstructure coarsening oxidation mechanical properties

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Alterations of soil aggregates and intra-aggregate organic carbon fractions after soil conversion from paddy soils to upland soils:Distribution,mineralization and driving mechanism

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Pedosphere 2024年第1期34卷 121-135页

作者： longfei KANG Jiamei WU Chunfeng zhang Baoguo ZHU Guixin CHU College of Life Science Shaoxing UniversityShaoxing 312000China The Key Laboratory of Oasis Eco-agriculture Xinjiang Production and Construction Group/Department of Resources and Environmental SciencesAgronomy CollegeShihezi UniversityShihezi 832000China Hunan Institute of Agricultural Environment and Ecology Changsha 410000China Jiamusi Branch Heilongjiang Academy of Agricultural SciencesJiamusi 154007China

Investigating the impacts of soil conversion on soil organic carbon(OC) content and its fractions within soil aggregates is essential for defining better strategies to improve soil structure and OC sequestration in terrestrial ecosystems. However, the consequences of soil conversion from paddy soil to upland soil for soil aggregates and intra-aggregate OC pools are poorly understood. Therefore, the objective of this study was to quantify the effects of soil conversion on soil aggregate and intra-aggregate OC pool distributions. Four typical rice-producing areas were chosen in North and South China, paired soil samples(upland soil converted from paddy soil more than ten years ago vs. adjacent paddy soil) were collected(0–20 cm) with three replicates in each area. A set of core parameters(OC preservation capacity, aggregate carbon(C) turnover, and biological activity index) were evaluated to assess the responses of intra-aggregate OC turnover to soil conversion. Results showed that soil conversion from paddy soil to upland soil significantly improved the formation of macro-aggregates and increased aggregate stability. It also notably decreased soil intra-aggregate OC pools, including easily oxidized OCa(EOCa), particulate OCa(POCa), and mineral-bound(MOCa) OC, and the sensitivity of aggregate-associated OC pools to soil conversion followed the order: EOCa(average reduction of 21.1%) > MOCa(average reduction of 15.4%) > POCa(average reduction of 14.8%). The potentially mineralizable C(C_(0)) was significantly higher in upland soil than in paddy soil, but the corresponding decay constant(k) was lower in upland soil than in paddy soil. Random forest model and partial correlation analysis showed that EOCa and pH were the important nutrient and physicochemical factors impacting k of C mineralization in paddy soil,while MOCa and C-related enzyme(β-D-cellobiohydrolase) were identified as the key factors in upland soil. In conclusion, this study evidenced that soil conversion

关键词： decay constant easily oxidized organic C macro-aggregate meso-aggregate micro-aggregate mineral-bound organic C particulate organic C potentially mineralizable C

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The mechanisms of enhanced thickness-dependent DC breakdown strength of EP/MWCNTs nanocomposites

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High Voltage 2024年第2期9卷 440-452页

作者： Zhen Li He Gao longfei zhang Shouming Wang Ji Liu Shengtao Li Key Laboratory of Engineering Dielectrics and Its Application Ministry of EducationHarbin University of Science and TechnologyHarbinChina State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong UniversityXi'anChina

Owing to advanced power electronic and electrical applications developing towards miniaturisation and integration,the thickness-dependent DC breakdown mechanism of epoxy/multiwall-carbon-nanotube nanocomposites is under *** results indicate that the breakdown strength of nanocomposites containing 0.05 wt%multiwall-carbon-nanotubes rises by~18%,and the breakdown strength falls exponentially with increasing *** clarify the microscopic mechanism,a simulation model of DC breakdown,including carriers transport and segmental dynamics,is developed,and the accordant simulation results with experimental results indicate that the thickness-dependent DC breakdown of epoxy/multiwall-carbon-nanotube nanocomposites is determined both by segment chain dynamics and charge *** to the breakdown model analysis,the effects of multiwall-carbon-nanotube on enhanced breakdown strength are caused by the increased amount of deep traps in the interfacial region,while the influence of thickness is attributed to the enlarged segment chain displacement and electric field distortion as the voltage raising time increases.

关键词： strength breakdown nanocomposites

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Haploidentical hematopoietic cell transplantation with or without an unrelated cord blood unit for adult acute myeloid leukemia:a multicenter,randomized,open-label,phase 3 trial

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Signal Transduction and Targeted Therapy 2024年第6期9卷 2669-2678页

作者： Biqi Zhou Jia Chen Tianhui Liu Yishan Ye Yanming zhang Yiyang Ding Hong Liu MingQing Zhu Xiao Ma Xiaoli Li longfei Zhao Zhihong Lin He Huang yang Xu Depei Wu National Clinical Research Center for Hematologic Diseases Jiangsu Institute of HematologyThe First Affiliated Hospital of Soochow UniversitySuzhouChina Institute of Blood and Marrow Transplantation Collaborative Innovation Center of HematologySoochow UniversitySuzhouChina Bone Marrow Transplantation Center The First Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiangChina Department of Hematology The Affiliated Huai’an Hospital of Xuzhou Medical University and The Second People’s Hospital of Huai’anHuai’anChina Soochow Hopes Hematology Hospital SuzhouChina Department of Hematology Hygeia Suzhou Yongding HospitalSuzhouChina

Coinfusion of unrelated cord blood(UCB)units in haploidentical hematopoietic cell transplantation(haplo-HCT)(haplo-cord HCT)for hematopoietic malignancies showed promising results in previous reports,but the efficiency of haplo-cord HCT in acute myeloid leukemia(AML)still lacks sufficient *** multicenter,randomized,phase 3 trial(*** NCT03719534)aimed to assess the efficacy and safety of haplo-cord HCT in AML patients.A total of 268 eligible patients aged 18-60 years,diagnosed with measurable residual disease in AML(excluding acute promyelocytic leukemia),with available haploidentical donors and suitable for allotransplantation,were randomly allocated(1:1)to receive haplo-cord HCT(n=134)or haplo-HCT(n=134).The 3-year overall survival(OS)was the primary endpoint in this *** median follow-up was 36.50 months(IQR 24.75-46.50).The 3-year OS of Haplo-cord HCT group was better than haplo-HCT group(80.5%,95%confidence interval[CI]:73.7-87.9 vs.67.8%95%CI 60.0-76.5,p=0.013).Favorable progression-free survival(70.3%,95%CI 62.6-78.8 vs.57.6%,95%CI 49.6-67.0,p=0.012)and cumulative incidence of relapse(12.1%,95%CI 12.0-12.2 vs.30.3%,95%CI 30.1-30.4,p=0.024)were observed in haplo-cord HCT *** 3-4 adverse events(AEs)within two years posttransplantation in the two groups were ***-cord HCT patients exhibited a faster cumulative incidence of neutrophil recovery(p=0.026)and increased T-cell reconstitution in the early period ***-cord HCT can improve OS in AML patients without excessive AEs,which may exert additional benefits for recipients of haplo-HCT.

关键词： hematopoietic acute phase

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Enhanced photoelectrochemical water splitting with a donor-acceptor polyimide

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Frontiers in Energy 2024年第4期18卷 463-473页

作者： Hongyu QU Xiaoyu XU longfei HONG Xintie WANG Yifei ZAN Huiyan zhang Xiao zhang Sheng CHU Key Laboratory of Energy Thermal Conversion and Control of the Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096China State Key Laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou 310027China

Polyimide(PI)has emerged as a promising organic photocatalyst owing to its distinct advantages of high visible-light response,facile synthesis,molecularly tunable donor-acceptor structure,and excellent physicochemical ***,the synthesis of high-quality PI photoelectrode remains a challenge,and photoelectrochemical(PEC)water splitting for PI has been less ***,the synthesis of uniform PI photoelectrode films via a simple spin-coating method was reported,and their PEC properties were investigated using melamine as donor and various anhydrides as *** influence of the conjugate size of aromatic unit(phenyl,biphenyl,naphthalene,perylene)of electron acceptor on PEC performance were studied,where naphthalene-based PI photoelectrode exhibited the highest photocurrent *** is resulted from the unification of widerange light absorption,efficient charge separation and transport,and strong photooxidation *** paper expands the material library of polymer films for PEC applications and contributes to the rational design of efficient polymer photoelectrodes.

关键词： polyimide(PI)film photoelectrochemistry band structure engineering aromatic unit

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Vibration-assisted material damage mechanism:From indentation cracks to scratch cracks

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Chinese Journal of Aeronautics 2024年第8期37卷 527-546页

作者： Bingrui LV Bin LIN Tianyi SUI Chunyan LIU Jinshuo zhang longfei WANG Xuhui CHEN Jingguo ZHOU Key Laboratory of Advanced Ceramics and Machining Technology Ministry of EducationTianjin UniversityTianjin 300072China Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin UniversityTianjin 300072China Science and Technology of Advanced Functional Composite Laboratory Aerospace Research Institute of Materials and Processing TechnologyBeijing 100076China

Vibration-assisted grinding is one of the most promising technologies for manufacturing optical components due to its efficiency and quality ***,the damage and crack propagation mechanisms of materials in vibration-assisted grinding are not well *** order to elucidate the mechanism of abrasive scratching during vibration-assisted grinding,a kinematic model of vibration scratching was *** influence of process parameters on the evolution of vibration scratches to indentation or straight scratches is revealed by displacement metrics and velocity ***,scratch and vibration scratch experiments were performed on quartz glass,and the results showed that the vibration scratch cracks are a combination of indentation cracks and scratch *** scratch cracks change from indentation cracks to scratch cracks as the indenter moves from the entrance to the exit of the workpiece or as the vibration frequency changes from high to low.A vertical vibration scratch stress field model is established for the first time,which reveals that the maximum principal stress and tensile stress distribution is the fundamental cause for inducing the transformation of the vibration scratch cracking *** model provides a theoretical basis for understanding of the mechanism of material damage and crack propagation during vibration-assisted grinding.

关键词： Vibration assisted grinding Indentation Vibration scratch Material removal mechanism Stress field model Crack propagation mechanism

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