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江山市片石砂土综合治理与合理开发研究报告

浙江林业科技 1995年第6期15卷 42-45页

作者： Group of Schist Sand Research(jiangshan Forestry Bureau of Zhejiang jiangshan 324100) 江山市林业局片石砂土项目课题组浙江省江山市林业局

采用了竹节沟、撩壕、块状挖穴整地方式，加速母质风化，提高林地保水保土能力；采用加客土、施基肥、容器苗等造林措施；并选用湿地松、木荷、枫香、楷杷、柑桔等多树种营造混交林和经济林；全面封山育林、育草，并加强抚育管理；采取... 详细信息

采用了竹节沟、撩壕、块状挖穴整地方式，加速母质风化，提高林地保水保土能力；采用加客土、施基肥、容器苗等造林措施；并选用湿地松、木荷、枫香、楷杷、柑桔等多树种营造混交林和经济林；全面封山育林、育草，并加强抚育管理；采取多种节能措施，保护森林植被。从而形成了一套完整的行之有效的保持水土、改良土壤、调节温差、提高造林成活率和保存率的综合治理配套技术和合理开发对策。项目研究５年来，成效显著；历来认为难以造林绿化的１．３３万ｈｍ２片石破土，经省林勘院抽查验收，全部消灭了荒山；人工造林合格面积０．２１万ｈｍ２，成活率、保存率９０％以上；有林地面积增长２１．４％，活立木蓄积量增长５４．６％经３年监测，幼林地与荒山比较，水土流失量减少７０％左右；治理开发工程投入产出比１：４．８６，项目区森林资源的生态效益和社会效益估值已达２．０８亿元／ａ。

关键词：综合治理经济生态社会效益片石砂土

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A Method for Traction Ability Research of a Rover Wheel on Mixed Planet Terrain with Movable Stones

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Space(Science & Technology) 2023年第1期3卷 141-149页

作者： jiangshan Du Tieqiu Huang School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China

The mixed terrains of terramechanics research are mainly composed of static stones and loose *** movement behavior of stones is often ignored while analyzing the influence of the wheel’s traction performance caused by mixed *** a wheel is in contact with the movable stone and with the loose soil at the same time,the residual soil model,therefore,is proposed to simulate the change of the contact force between the wheel and the remaining loose soil caused by the failure of the loose soil in the area covered by *** plastic homogeneous soil mechanics model is proposed based on the soil’s mechanical *** is used for simulating the reaction force provided by soil to the moving *** mechanical models are compiled into the simulation programs,which are called by Adams to calculate the contact forces and moments of the planetary rover’s wheels in the mixed terrain with the movable stone and loose *** out soil bin tests under the same experimental conditions,the comparative analysis of the simulation and experiment for a wheel in contact with 4 types of stones shows that the comparison results are in good agreement,which can verify the effectiveness of the proposed models to an extent.

关键词： soil properties loose

Comparison of Snowfall Variations over China Identified from Different Snowfall/Rainfall Discrimination Methods

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Journal of Meteorological Research 2020年第5期34卷 1114-1128页

作者： jiangshan LUO Haishan CHEN Botao ZHOU Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research L aboratory of Climate and Environmental Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science&TechnologyNanjing 210044 School of Atmospheric Sciences Nanjing University of Information Science&TechnologyNanjing 210044

Based on the snowfall observations at 836 surface weather stations in China and the Daily Surface Climate Variables of China version 3.0 dataset for 1961–2013, capability of five methods with different objective criteria for identifying wintertime snowfall is evaluated, to provide reference for application of these methods in snowfall/rainfall discrimination. Methods Ⅰ, Ⅱ, Ⅲ, Ⅳ, and Ⅴuse the daily average surface air temperature(Ta), wet-bulb temperature(Tw), dynamic threshold Tw, 0-cm ground temperature, and 700–850-hPa thickness, respectively, to identify the snowfall. The results show that the climatological distribution of snowfall can be well produced by Methods Ⅰ, Ⅱ, and Ⅲ. Method Ⅳ underestimates the snowfall days in eastern Tibetan Plateau(ETP), and Method Ⅴ cannot yield the actual large numbers of snowfall days and amounts. Accordingly, the linear trends of snowfall days estimated from Methods Ⅰ, Ⅱ, and Ⅲ largely agree with the observations, while a discrepancy is found in the linear trend of snowfall amounts over southeastern China(SEC). For interannual and decadal variations of snowfall, Method Ⅴ shows the worst performance. It is more reasonable to use Tw to distinguish snowfall from rainfall instead of Ta, 0-cm ground temperature, and 700–850-hPa thickness;and the reference thresholds of Tw in northeastern China(NEC), northwestern China(NWC), ETP, and SEC are-1.5,-1.5,-0.4, and-0.3°C, respectively. The above results are beneficial to identifying snowfall in short-term climate prediction.

关键词： snowfall/rainfall discrimination method wintertime snowfall wet-bulb temperature(Tw) threshold comparison

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High-efficiency stabilization of dredged sediment using nano-modified and chemical-activated binary cement

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第8期15卷 2117-2131页

作者： Lei Lang Bing Chen jiangshan Li State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China Department of Civil Engineering Shanghai Jiao Tong UniversityShanghai200240China

High-efficiency disposal of dredged sediment(DS)has become an imperative geo-environmental engineering issue due to the limited landfilling space and severe environmental *** study firstly developed a novel high-efficiency nano-modified and chemical-activated binary cement(NBC),which was composed of binary cement(BC)consisting ordinary Portland cement(OPC)and ground granulated blast-furnace slag(GGBS),chemical-activator and *** effects of chemical-activation and nano-modification on the strength development of BC-stabilized DS(BCDS),and the optimum mix of NBC were respectively achieved via a series of unconfined compressive strength and orthogonal ***,the high-efficiency and economic applicability of NBC in DS stabilization were evaluated by comparing with ***,the microstructure and mineral composition evolutions inside NBCstabilized DS(NDS)were explored by conducting X-ray diffraction(XRD)and scanning electron microscopy(SEM)*** results show that both chemical-activation and nano-modification could effectively improve the strength gain of BCDS,and compared with single chemical-activator and nanomodifier,the composite chemical-activators and nano-modifiers exhibited better *** on BC with OPC/GGBS mass ratio of 1:1,both anhydrous sodium metasilicate/anhydrous sodium sulfate(SM/SS)and nano-SiO_(2)/nano-MgO(NS/NM)with mass ratio of 1:9 were respectively determined to be optimum chemical-activator and *** optimum mass ratio of BC,SM/SS and NS/NM was 20:2:1,*** optimum mix of *** with OPC,NBC exhibited higher stabilization efficiency and better economic *** generation of calcium silicate hydrate(CSH),calcium aluminate hydrate(CAH)and ettringite contributed to the formation of dense cemented soil matrix inside NDS,and a conceptual micro-mechanism model characterizing the strength development under the coupling action of chemical-activation and nano-modification was prop

关键词： Dredged sediment(DS) Stabilization Chemical-activation Nano-modification Microstructure

Novel Partitioned Time-Stepping Algorithms for Fast Computation of Random Interface-Coupled Problems with Uncertain Parameters

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Numerical Mathematics(Theory,Methods and Applications) 2024年第1期17卷 145-180页

作者： Yizhong Sun jiangshan Wang Haibiao Zheng School of Mathematical Sciences East China Normal UniversityShanghaiChina School of Mathematical Sciences Ministry of Education Key Laboratory of Mathematics and Engineering ApplicationsShanghai Key Laboratory of PMMPEast China Normal UniversityShanghaiChina

The simulation of multi-domain,multi-physics mathematical models with uncertain parameters can be quite demanding in terms of algorithm design and com-putation *** main objective in this paper is to examine a physical interface coupling between two random dissipative systems with uncertain *** to the complexity and uncertainty inherent in such interface-coupled problems,un-certain diffusion coefﬁcients or friction parameters often arise,leading to consid-ering random *** employ Monte Carlo methods to produce independent and identically distributed deterministic heat-heat model samples to address ran-dom systems,and adroitly integrate the ensemble idea to facilitate the fast calcu-lation of these *** achieve unconditional stability,we introduce the scalar auxiliary variable(SAV)method to overcome the time constraints of the ensemble implicit-explicit ***,for a more accurate and stable scheme,the ensemble data-passing algorithm is raised,which is unconditionally stable and convergent without any auxiliary *** algorithms employ the same co-efﬁcient matrix for multiple linear systems and enable easy parallelization,which can signiﬁcantly reduce the computational ***,numerical experiments are conducted to support the theoretical results and showcase the unique features of the proposed algorithms.

关键词： Scalar auxiliary variable ensemble algorithm random interface-coupled problems implicit-explicit partitioned method data-passing partitioned method

Experimental Study and Simulation of Cavitation Shedding in Diesel Engine Nozzle using Proper Orthogonal Decomposition and Large Eddy Simulation

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Journal of Thermal Science 2023年第4期32卷 1487-1500页

作者： HE Jiajun AN Qingsong JIN jiangshan FENG Shuai ZHANG Kemu Key Laboratory of Medium-Low Temperature Thermal Energy Efficient Utilization of Ministry of Education School of Mechanical EngineeringTianjin UniversityTianjin300350China Shanghai Marine Diesel Engine Research Institute Shanghai201108China

The unsteady cloud cavitation shedding in fuel nozzles greatly influences the flow characteristics and spray break-up of fuel,thereby causing erosion *** the application of high-pressure common rail systems in diesel engines,this phenomenon frequently occurs in the nozzle;however,cloud cavitation shedding frequency and its mechanism have yet to be studied in *** this study,a visualization experiment and proper orthogonal decomposition(POD)method were used to study the variations in the cavitation shedding frequency and analyze the cavitation flow structure in a 3 mm square *** addition,large eddy simulation(LES)was performed to explore the causes of cavitation shedding,and the relationship between cavitation and *** the increase of the inlet and outlet pressure differences,and fuel temperatures,the degree of cavitation intensified and the frequency of cavitation cloud shedding gradually *** demonstrated the relationship between the vortices,and the development,shedding,and collapse of the cavitation ***,the re-entrant jet mechanism was found to be the main reason for the shedding of cavitation *** comparative experiments,the fluctuation of the vapor volume fraction in the nozzle hole accurately predicted the regions with stable cavitation,re-entrant jet,cavitation cloud shedding,and *** frequency of cavitation shedding can then be *** study employed an instantaneous POD method based on instantaneous cavitation images,which can distinguish the evolution process and characteristics of cavitation in the nozzle hole of diesel engines.

关键词： diesel engine proper orthogonal decomposition cavitation shedding cavitation collapse large eddy simulation

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Boosting the self-trapped exciton emission in vacancy-ordered double perovskites via supramolecular assembly

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Chinese Journal of Structural Chemistry 2024年第6期43卷 1-2页

作者： Xingwen Cheng Haoran Ren jiangshan Luo Institute of Quantum and Sustainable Technology(IQST) School of Chemistry and Chemical EngineeringJiangsu UniversityZhenjiang212013China

All-inorganic 3D lead-free vacancy-ordered double perovskites(DPs)in the A_(2)MX_(6)phase have garnered significant attention in the fields of photovoltaics and light-emitting diodes(LED)due to their exceptional optoelectronic properties[1].These properties encompass a high optical absorption coefficient,tunable bandgap,and long carrier diffusion dis-tance.

关键词： optoelectronic vacancy double

Tensile strength behavior of cement-stabilized dredged sediment reinforced by polypropylene fiber

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 380-392页

作者： Lei LANG jiangshan LI Xin CHEN Lijun HAN Ping WANG State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicChinese Academy of SciencesWuhan 430071China Hubei Provincial Key Laboratory of Contaminated Sludge and Soil Science and Engineering Wuhan 430071China University of Chinese Academy of Sciences Beijing 100049China

This study evaluated the feasibility of using polypropylene fiber(PF)as reinforcement in improving tensile strength behavior of cement-stabilized dredged sediment(CDS).The effects of cement content,water content,PF content and length on the tensile strength and stress–strain behavioral evolutions were evaluated by conducting splitting tensile strength ***,the micro-mechanisms characterizing the tensile strength behavior inside PF-reinforced CDS(CPFDS)were clarified via analyzing macro failure and microstructure *** results indicate that the highest tensile strengths of 7,28,60,and 90 d CPFDS were reached at PF contents of 0.6%,1.0%,1.0%,and 1.0%,exhibiting values 5.96%,65.16%,34.10%,and 35.83%higher than those of CDS,***,3 mm,PF of showed the best reinforcement *** CPFDS exhibited obvious tensile strain-hardening characteristic,and also had better ductility than *** mix factor(C_(C)^(a)/C_(w)^(b))and time parameter(q_(t0)(t))of CDS,and the reinforcement index(k_(t-PF))of CPFDS were used to establish the tensile strength prediction models of CDS and CPFDS,considering multiple *** PF“bridge effect”and associated cementation-reinforcement coupling actions inside CPFDS were mainly responsible for tensile strength behavior *** key findings contribute to the use of CPFDS as recycled engineering soils.

关键词： dredged sediment chemical stabilization fiber reinforcement splitting tensile strength micro-mechanisms

Efficient Ring Signature Scheme Without Random Oracle from Lattices

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Chinese Journal of Electronics 2019年第2期28卷 266-272页

作者： GAO Wen HU Yupu WANG Baocang CHEN jiangshan WANG Xin College of Electrical and Information Engineering Shaanxi University of Science and Technology State Key Laboratory of Integrated Service Networks Xidian University School of Mathematics and Statistics Minnan Normal University School of Computer Science Shaanxi Normal University

Among post-quantum alternatives, latticebased cryptography is the most promising one, due to its simple operations, reduction from aver-age-case to worstcase hardness, and supporting of rich functionalities. Ring signature enables a user to sign anonymously on behalf of an adaptively chosen group, and has multiple applications in anonymous e-voting, anonymous authentication, whistle blowing etc. However, most lattice-based ring signature schemes were constructed in the random oracle model from lattice basis delegation and they suffer large verification key sizes as a common disadvantage. This work proposes an efficient ring signature scheme from lattice basis delegation without random oracle based on the extended split-SIS problem, whose security is approximately as hard as the worst-case SIVP problem. Our scheme is proved to be anonymous and existentially unforgeable under latticebased assumptions. Finally, the verification key size is significantly reduced to a small constant, instead of increasing linearly with the number of ring members.

关键词： Lattice-based cryptography Digital signature Ring signature