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Hydrological Responses and Flow Pathways in an Acrisol on a Forested Hillslope with a Monsoonal Subtropical Climate

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Pedosphere 2017年第6期27卷 1037-1048页

作者： Lars-Erik SORBOTTEN Jannes STOLTE wang yanhui Jan MULDER Norconsult AS N-1338 Sandvika(Norway) Norwegian Institute of Bioeconomy Research(NIBIO) N-1430 Aas(Norway) Research Institute of Forest Ecology Environment and ProtectionChinese Academy of ForestryBeijing 100091(China) Department of Environmental Sciences Norwegian University of Life SciencesN-1432 Aas(Norway)

The nature of subsurface flow depends largely on hydraulic conductivity of the vadoze zone, permeability of the underlying bedrock, existence of soil layers differing in hydraulic properties and macropore content, soil depth, and slope *** of flow pathways on forested hillslopes is essential to understand hydrological dynamics and solute transport ***, with their argic Bt horizons, are challenging in this *** further elucidate flow pathways of water and short-term variability of soil moisture patterns in Acrisols, a field study was conducted on a forested hillslope in a sub-catchment of the Tie Shan Ping(TSP)watershed, 25 km northeast of Chongqing City, *** catchment is covered by a mixed secondary forest dominated by Masson pine(Pinus massoniana).Soil saturated hydraulic conductivity(K sat) was significantly reduced at the interface between the AB and Bt horizons(2.6 × 10^(-5) vs.1.2 × 10^(-6) m s^(-1)), which led to that the flow volume generated in the Bt horizon was of little quantitative importance compared to that in the AB *** was a marked decrease in porosity between the OA and AB horizons, with a further decrease deeper in the mineral ***, the content of soil pores > 300 μm was higher in the AB horizon(14.3%)than in the Bt horizon(6.5%).This explained the difference in soil K sat *** study showed that Bt horizon had limited water transport capability, forcing part of the infiltrated rainwater as interflow through the OA and AB ***, the topsoil responded quickly to rainfall events, causing frequent cycles of saturation and aeration of soil pores.

关键词： dye tracer hillslope hydrology hydraulic conductivity preferential flow soil pores subsurface lateral flow

Environmental and canopy conditions regulate the forest floor evapotranspiration of larch plantations

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Forest Ecosystems 2022年第5期9卷 606-616页

作者： Zebin Liu yanhui wang Pengtao Yu Lihong Xu Songping Yu Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland Administration Ecology and Nature Conservation InstituteChinese Academy of ForestryBeijing100091China School of Soil and Water Conservation Beijing Forestry UniversityBeijing100083China

Background:Integrated forest-water management focusing on forest-water coordination is an important way to alleviate water use conflicts among forests and other sectors in vast dryland *** floor evapotranspiration(FE),which is an important component of forest evapotranspiration,accounts for a large proportion of the water consumed in arid *** how environmental and canopy conditions impact FE has important significance for guiding integrated forest-water management in a changing ***:The microlysimeter(ML)-measured evapotranspiration(FE_(ML)),reference evapotranspiration(ET_(o)),volumetric soil moisture(VSM),and canopy leaf area index(LAI)were monitored in a Larix principis-rupprechtii plantation located in the semi-humid Liupan Mountains of Northwest China in 2019(June–September)and 2021(May–September).The response functions of the FE coefficient(the ratio of daily FEML to ET_(o))to the individual factors of VSM and LAI were determined using upper boundary lines of scatter diagrams of measured *** framework of the daily FE(FE_(ML))model was established by multiplying the response functions to individual factors and then calibrated and validated using measured data to assess the FE response to environmental and canopy ***:(1)The FE coefficient increased first rapidly and then slowly with rising VSM but decreased slowly with rising LAI.(2)The simple daily FE(FE_(ML))model developed by coupling the impacts of ET_(o),LAI,and VSM in this study performed well for predicting FE.(3)The impacts of ET_(o),LAI,and VSM were quantified using the FE(FE_(ML))model,e.g.,at a given VSM,the impact of ETo on FE increased obviously with decreasing LAI;at a given ET_(o),the impact of LAI on FE increased with rising VSM.(4)In the two study years,when directly using the microlysimeter measurement,the real FE on the forest floor was overestimated when the VSM in microlysimeters was above 0.215 but underestimated below 0.215 due

关键词： Larch plantation Forest floor evapotranspiration Reference evapotranspiration Soil water content Canopy structure

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老年人生前预嘱的域外探索及对我国的启示

南京中医药大学学报(社会科学版) 2025年第1期26卷 9-15页

作者：孙珂姚峥嵘王艳翚南京中医药大学卫生经济管理学院江苏南京210023 南京中医药大学护理学院江苏南京210023 南京中医药大学养老服务与管理学院江苏南京210023

老年人生前预嘱制度体现了社会对老年人自主决定权的维护和尊重,以美国、英国和德国为代表的域外国家和地区普遍将该制度合法化,我国内地地区虽有民间组织对其进行推广,但在立法进程上却相对缓慢。介绍了美国、英国和德国对老年人生前... 详细信息

老年人生前预嘱制度体现了社会对老年人自主决定权的维护和尊重,以美国、英国和德国为代表的域外国家和地区普遍将该制度合法化,我国内地地区虽有民间组织对其进行推广,但在立法进程上却相对缓慢。介绍了美国、英国和德国对老年人生前预嘱的相关立法及实践,并分析其对我国老年人生前预嘱制度构建的借鉴价值,提出应通过明确生前预嘱适用主体条件、健全生前预嘱执行程序、建立生前预嘱监督机制、完善安宁疗护配套建设以及推广生死观教育等方式为老年人医疗决定权的实现提供支撑,以更好地维护老年人尊严。

关键词：老龄化生前预嘱自我决定权安宁疗护尊严死

Dynamic Model and Motion Characteristics of an Underwater Glider with Manta-inspired Wings

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Journal of Bionic Engineering 2022年第1期19卷 1-15页

作者： Yaqiang Zhu Yuhong Liu Lianhong Zhang yanhui wang Wendong Niu Cheng Huang Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education School of Mechanical EngineeringTianjin UniversityTianjin300350China The Joint Laboratory of Ocean Observing and Detection Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao266237China

An underwater glider with bionic wings controlled by two operating modes is proposed to perform a variety of marine exploration *** system composition of the vehicle and the structural design of wings inspired by manta ray are *** bionic wings can keep outstretched or realize oscillating motions according to the operating modes of the vehicle.A universal dynamic model of the vehicle was derived from multibody ***,sailing and steering motions were simulated based on the dynamic model to illustrate the dynamic behaviors of the vehicle under different types of propulsion *** results obtained through simulated calculation are basically consistent with the experimental data,which indicate that the developed dynamic model is applicable to describe the motion characteristics of the *** were conducted in coastal area to analyze the propulsive characteristics of the bionic wings and sea trials involving multifarious motions were carried out,the applicability of the vehicle in marine environment was verified.

关键词： Underwater glider Bionic wing Oscillatory propulsion Dynamic model

SPECT MPI参数研究进展及其临床价值

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中华核医学与分子影像杂志 2025年第1期45卷 53-56页

作者：李媛媛王若楠汪燕辉胡迎琦刁鑫李思进山西医科大学第一医院核医学科、分子影像精准诊疗省部共建协同中心太原030001

SPECT心肌灌注显像(MPI)可一站式获得心肌灌注、形态学、功能学及机械同步性等众多参数,成为各类心血管疾病(CVD)诊疗流程中必不可少的无创检查技术。随着心脏专用SPECT机、显像方案及图像重建算法技术的不断发展,其在CVD诊疗中的应用... 详细信息

SPECT心肌灌注显像(MPI)可一站式获得心肌灌注、形态学、功能学及机械同步性等众多参数,成为各类心血管疾病(CVD)诊疗流程中必不可少的无创检查技术。随着心脏专用SPECT机、显像方案及图像重建算法技术的不断发展,其在CVD诊疗中的应用不断拓展。该文回顾了近年来SPECT MPI定性、半定量及定量参数的研究进展,阐述各类参数的阈值、影响因素及应用价值。

关键词：心肌灌注显像体层摄影术,发射型计算机,单光子发展趋势

The renascence of industrial historic buildings——Taking the protective remolding and reusing of Chenguang Mechanical Factory in Nanjing as an example

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Science China(Technological Sciences) 2009年第9期52卷 2502-2509页

作者： wang yanhui Research Institute of Architecture,Southeast University,Nanjing 210096,China 1. Research Institute of Architecture Southeast University Nanjing 210096 China

The protective remolding and reusing of industrial historic buildings and sites is regarded as a great scientific matter in today's urban development. Based on discussing its significance and value,this paper,taking a specific example,makes a systematic discussion on the design strategy and method from the aspects of overall planning,remolding the old buildings,designing the new buildings,etc.

关键词： industrial historic buildings and sites protective remolding and reusing renascence strategy

Structure and characteristics of Si-coated diamond grits

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金刚石与磨料磨具工程 2005年第6期25卷 13-15页

作者： Lu Jing wang yanhui Qi Xuehai Huang Hao Zang Jianbing Key Laboratory of Metastable Materials Science ＆ Technology Hebei Yanshan University Qinhuangdao 066004 China College of Materials Science ＆ Engineering Yanshan University Qinhuangdao 066004 China

During sintering process of diamond tools, metal bond containing graphitizing elements such as Fe, Co, Ni seriously e-rodes diamond grits, which reduces the strength of the diamond grits. In this paper, silicon films were coated on the surface of dia-mond grits by means of atomic layer deposition (ALD) from gaseous SiH4. Fourier transform infrared (FTIR) spectra, X-ray dif-fraction (XRD) and Atomic force microscopy (AFM) were utilized to analyze the structure and the morphology of Si-coated dia-mond respectively. The results suggested that the film was cubic-phase polycrystalline silicon and the surface of the film was smoothand continuous. According with the adsorption mechanism of SiH4on the surface of diamond grits, the stretching and bendingmodes of SiH2and SiH3both existed. Differential thermal analysis (DTA) was used to compare the thermal stability of coated dia-mond and uncoated diamond. Owning to the protection of silicon films the starting oxidation temperature of coated diamond reachedas high as 920℃, which was much higher than that of uncoated diamond. Bending experiment was conducted to measure the ben-ding strength of Fe-Cu-Sn-Ni based metal bond diamond blade. In comparison with uncoated diamond, the bending strength of Si-coated diamond blade increased by16.2%, scan electron microscope (SEM) observation of the blade fracture revealed that the de-posited silicon films not only protected the diamond grits from erosion during sintering process but also realized the strong bindingbetween the diamond grits and the bond.

关键词： ALD 人造金刚石结构性能

On UAV Serving Node Deployment for Temporary Coverage in Forest Environment:A Hierarchical Deep Reinforcement Learning Approach

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Chinese Journal of Electronics 2023年第4期32卷 760-772页

作者： wang Li WU Xuewei wang yanhui XIAO Zhe LI Liang FEI Aiguo School of Computer Science (National Pilot Software Engineering School) Beijing University of Posts and Telecommunications School of Electronic Engineering Beijing University of Posts and Telecommunications

Unmanned aerial vehicles(UAVs) can be effectively used as serving stations in emergency communications because of their free movements, strong flexibility, and dynamic coverage. In this paper, we propose a coordinated multiple points based UAV deployment framework to improve system average ergodic rate, by using the fuzzy C-means algorithm to cluster the ground users and considering exclusive forest channel models for the two cases, i.e., associated with a broken base station or an available base station. In addition, we derive the upper bound of the average ergodic rate to reduce computational complexity. Since deep reinforcement learning(DRL) can deal with the complex forest environment while the large action and state space of UAVs leads to slow convergence, we use a ratio cut method to divide UAVs into groups and propose a hierarchical clustering DRL(HC-DRL) approach with quick convergence to optimize the UAV deployment. Simulation results show that the proposed framework can effectively reduce the complexity, and outperforms the counterparts in accelerating the convergence speed.

关键词： Deep learning Base stations Simulation Clustering algorithms Forestry Reinforcement learning Autonomous aerial vehicles

Numerical study of atmospheric-pressure argon plasma jet propagating into ambient nitrogen

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Plasma Science and Technology 2022年第5期24卷 17-28页

作者： Yuanyuan JIANG yanhui wang Yamin HU Jiao ZHANG Dezhen wang Key Laboratory of Materials Modification by Laser Ion and Electron Beams(Ministry of Education)School of PhysicsDalian University of TechnologyDalian 116024People’s Republic of China

A 2D axial symmetry fluid model is applied to study the features of an atmospheric-pressure argon(Ar) plasma jet propagating into ambient nitrogen(N_(2)) driven by a pulsed voltage,emphasizing the influence of gas velocity on the dynamic characteristics of the jet. The results show that the Ar jet exhibits a cylindrical-shaped channel and the jet channel gradually shrinks with the increase in propagation length. The jet propagation velocity varies with time. Inside the dielectric tube, the plasma jet accelerates propagation and reaches its maximum value near the nozzle. Exiting the tube, its velocity quickly decreases and when approaching the metal plane,the decrease in jet velocity slows down. The increase in gas speed results in the variation of jet spatial distribution. The electron density presents a solid structure at lower gas flow speeds,whereas an annular structure can be observed under the higher gas flow velocity in the ionization head. The jet length increases with the flow velocity. However, when the flow velocity exceeds a critical value, the increase in the rate of the plasma jet length slows down. In addition, the gas velocity effect on the generation and transport of the reactive particles is also studied and discussed.

关键词： atmospheric-pressure argon plasma jet gas flow velocity 2D simulation propagation characteristics reactive species