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DEFORMATION OF THE EASTERN HIMALAYAN SYNTAXIS: EVIDENCES FROM STRUCTURES AND KINEMATICS OF ITS WESTERN BOUNDARY

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地学前缘 2000年第S1期7卷 18-20页

作者： Zhang j.,zhong D.,Ding L.,j. j.,He S(Institute of Geology and Geophysics, Chinese Academy of Sciences, Beij.ng 100029,China)

The western boundary of the Eastern Himalayan Syntaxis (EHS) is a deformation belt up to 30km wide (Fig.1). Trending ca. N35°E, it separates the Gangdise magmatic belt in the west from the gneiss of EHS in the east. Its rock association, mica\|schist, quartzite, marble, and amphibolite, can be traced to the south to Gangdise belt and they were probably metamorphosed from the sediments along Yarlung Zangbo. This belt consists of several intensive deformation zones, the largest one of which is along the belt’s western margin from Dongj.g to Mainling and we called this ca. 10km wide shear zone as the Dongj.g\|Mainling shear zone (DMSZ).DMSZ experienced earlier ductile shear and later ductile\|brittle normal faulting. The earlier deformation produced mylonitic rocks. Their foliation trends N30°～40°E and dips northwest with the angle ranging from 55°to 80°, steepening northeastward. The penetrative kinematic lineation in the rocks has a varying attitude along the trend of DMSZ. It dips southwest with an angle of ca.35° in the southwest near Mainling, whereas dips northeast in the northeast. Moreover, the northeast dipping lineation steepens northeastwards, e.g., its angle ranges form 30° to 45° in the segment from Serkyim La to Dongj.g but becomes 60～70° in the northeast most in another zone near Parlung. Kinematic indicators show that the motion of DMSZ had a left\|lateral slipping component, but the vertical motion components were different in the southwest from the northeast. From Serkyim La to the northeast, DMSZ had a kinematics of NW plate (Gangdise belt) thrusting over the SE plate (EHS) and its thrusting component increased toward northeast. However, the DMSZ has a vertical motion with the SE plate (EHS) as the uplifting plate.

关键词： Eastern Himalayan Syntaxis indentation uplift

CHARACTERISTICS OF THE REGIONAL TOURISM TRANSPORT NETWORK——taking the tourism region along the Yangtze River as an example

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CHARACTERISTICS OF THE REGIONAL TOURISM TRANSPORT NETWORK—...

Multi boron-doping effects in hard carbon toward enhanced sodium ion storage

第一届交通运输工程国际学术会议

作者： j. zhong and j. Zhang Department of Land Resources and Tourism Sciences, Nanj.ng University, Nanj.ng 210093, P. R. China

The aim of this paper is to explore characteristics of overland transport network of tourism cities along the Yangtze River. General characteristics and accessibility of tourism transport network are both investigated. The result shows that a good structure of transport network does not always ensure high accessibility. In order to learn the transport network comprehensively, we propose general characteristics and accessibility should be researched at the same time. Finally, we put forward some specific suggestions for development of tourism transport network in this tourism region.

关键词： tourism region transport network accessibility

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j.urnal of Energy Chemistry 2025年第1期100卷 730-738页

作者： Peng Zheng Wang Zhou Ying Mo Biao Zheng Miaomiao Han Qin zhong Wenwen Yang Peng Gao Lezhi Yang j.lei Liu College of Materials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean Energy Hunan Province Key Laboratory for Advanced Carbon Materials and Applied Technology Hunan University Greater Bay Area Institute for Innovation Hunan University Changsha Research Institute of Mining & Metallurgy Co. LTD.

Hard carbon （HC） has been considered as promising anode material for sodium-ion batteries （SIBs）.The optimization of hard carbon’s microstructure and solid electrolyte interface （SEI） property are demonstrated effective in enhancing the Na+storage capability,however,a one-step regulation strategy to achieve simultaneous multi-scale structures optimization is highly ***,we have systematically investigated the effects of boron doping on hard carbon’s microstructure and interface chemistry.A variety of structure characterizations show that appropriate amount of boron doping can increase the size of closed pores via rearrangement of carbon layers with improved graphitization degree,which provides more Na+storage ***-situ Fourier transform infrared spectroscopy/electrochemical impedance spectroscopy （FTIR/EIS） and X-ray photoelectron spectroscopy （XPS） analysis demonstrate the presence of more BC3and less B–C–O structures that result in enhanced ion diffusion kinetics and the formation of inorganic rich and robust SEI,which leads to facilitated charge transfer and excellent rate *** a result,the hard carbon anode with optimized boron doping content exhibits enhanced rate and cycling *** general,this work unravels the critical role of boron doping in optimizing the pore structure,interface chemistry and diffusion kinetics of hard carbon,which enables rational design of sodium-ion battery anode with enhanced Na+storage performance.

关键词： X ray photoelectron spectroscopy

Scale Effects of Geographical Soil Datasets on Soil Carbon Estimation in Louisiana,USA:A Comparison of STATSGO and SSURGO

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Pedosphere 2011年第4期21卷 491-501页

作者： B. zhong Y. j. XU School of Renewable Natural Resources Louisiana State University Agricultural Center Baton Rouge LA 70803 (USA)

Estimation of soil organic carbon （SOC） pools and fluxes bears large uncertainties because SOC stocks vary greatly over geographical space and through time. Although development of the U.S. Soil Survey Geographic Database （SSURGO）, currently the most detailed level with a map scale ranging from 1：12 000 to 1：63 360, has involved substantial government funds and coordinated network efforts, very few studies have utilized it for soil carbon assessment at the large landscape scale. The obj.ctives of this study were to 1） compare estimates in soil organic matter among SSURGO, the State Soil Geographic Database （STATSGO）, and referenced field measurements at the soil map unit; 2） examine the influence of missing data on SOC estimation by SSURGO and STATSGO; 3） quantify spatial differences in SOC estimation between SSURGO and STATSCO, specifically for the state of Louisiana; and 4） assess scale effects on soil organic carbon density （SOCD） estimates from a soil map unit to a watershed and a river basin scale. SOC was estimated using soil attributes of SSURGO and STATSGO including soil organic matter （SOM） content, soil layer depth, and bulk density. Paired t-test, correlation, and regression analyses were performed to investigate various relations of SOC and SOM among the datasets. There were positive relations of SOC estimates between SSURGO and STATSGO at the soil map unit （R2 = 0.56, n = 86, t = 1.65, P = 0.102; depth： 30 cm）. However, the SOC estimated by STATSGO were 9%, 33% and 36~ lower for the upper 30-cm, the upper l-m, and the maximal depth （up to 2.75 m） soils, respectively, than those from SSURGO. The difference tended to increase as the spatial scale changes from the soil map unit to the watershed and river basin scales. Compared with the referenced field measurements, the estimates in SOM by SSURGO showed a closer match than those of STATSCO, indicating that the former was more accurate than the latter in SOC estimation, both in spatial and temporal resoluti

关键词： carbon accounting climate change GIS soil organic carbon soil organic matter

Regional climate model downscaling may improve the prediction of alien plant species distributions

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Frontiers of Earth Science 2014年第4期8卷 457-471页

作者： Shuyan LIU Xin-zhong LIANG Wei GAO Thomas j. STOHLGREN Earth System Science Interdisciplinary Center University of Maryland College Park MD 20740 USA Department of Atmospheric and Oceanic Sciences University of Maryland College Park MD 20740 USA Department of Ecosystem Science and Sustainability Colorado State University Fort Collins CO 80523 USA Fort Collins Science Center U.S. Geological Survey Fort Collins CO 80526 USA

Distributions of invasive species are commonly predicted with species distribution models that build upon the statistical relationships between observed species presence data and climate data. We used field observations, climate station data, and Maximum Entropy species distribution models for 13 invasive plant species in the United States, and then compared the models with inputs from a General Circulation Model （hereafter GCM-based models） and a downscaled Regional Climate Model （hereafter, RCM-based models）. We also compared species distributions based on either GCM-based or RCM-based models for the present （1990-1999） to the future （2046- 2055）. RCM-based species distribution models replicated observed distributions remarkably better than GCM- based models for all invasive species under the current climate. This was shown for the presence locations of the species, and by using four common statistical metrics to compare modeled distributions. For two widespread invasive taxa （Bromus tectorum or cheatgrass, and Tamarix spp. or tamarisk）, GCM-based models failed miserably to reproduce observed species distributions. In contrast, RCM-based species distribution models closely matched observations. Future species distributions may be significantly affected by using GCM-based inputs. Because invasive plants species often show high resilience and low rates of local extinction, RCM-based species distribution models may perform better than GCM-based species distribution models for planning containment programs for invasive species.

关键词： climate change species distribution model,Maxent downscaling

“大、小、重、慢”疾病定义与全科医生“4善”定位的探讨

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中国全科医学 2025年第1期28卷 125-128页

作者：李敏王仲清华大学附属北京清华长庚医院临床医学院全科医学系北京市102218 北京清华长庚医院全科与健康医学部北京市102218

随着我国医药卫生体制的深度改革,特别是分级诊疗制度的推进,全科医生在基层医疗保健体系中的角色日益重要。全科医生不仅是居民健康的第一道防线,更是常见疾病预防、诊断、治疗及健康教育的关键执行者。国家对全科医生提出了“小病善... 详细信息

随着我国医药卫生体制的深度改革,特别是分级诊疗制度的推进,全科医生在基层医疗保健体系中的角色日益重要。全科医生不仅是居民健康的第一道防线,更是常见疾病预防、诊断、治疗及健康教育的关键执行者。国家对全科医生提出了“小病善治、大病善识、重病善转、慢病善管”的临床定位。本文通过问答形式,分析“小、大、重、慢”疾病的分类与全科医生的“4善”定位,探讨全科医生在新医改时代下的重要职能及挑战。访谈者认为虽然分级诊疗制度旨在优化医疗资源配置,但在实践中仍面临“大、小、重、慢”疾病分类的模糊性和基层医疗资源的不均衡分配等问题。全科医生在这个体系中扮演着至关重要的角色,其需要具备综合的临床诊疗能力,并与专科医生共同制定临床判断标准和诊疗标准。为了应对这些挑战并充分发挥全科医生在现代医疗体系中的作用,迫切需要对全科医学教育和实践进行进一步改革与优化,同时强化全科医生的角色定位,以确保在提升医疗服务质量和效率的同时,实现公平和可持续的健康保障体系。

关键词：全科医学全科医生分级诊疗医疗体系改革疾病分类医疗资源优化

学生干部经历对大学生连续创业行为的影响——信息资本的中介作用

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高校教育管理 2025年第1期19卷 99-112页

作者：钟云华杨洋湖南师范大学乡村教育研究中心湖南长沙410081 厦门大学教育研究院福建厦门361005

学生干部经历对提升大学生创业能力具有重要作用。深入评估学生干部经历对大学生连续创业行为的促进效应,不仅有助于全面衡量学生干部的育人成效,而且能为我国高校创新创业人才培养机制的深化改革提供关键依据。本研究以925位大学生创... 详细信息

学生干部经历对提升大学生创业能力具有重要作用。深入评估学生干部经历对大学生连续创业行为的促进效应,不仅有助于全面衡量学生干部的育人成效,而且能为我国高校创新创业人才培养机制的深化改革提供关键依据。本研究以925位大学生创业者为研究对象,综合采用Logit模型、倾向得分匹配、中介效应检验和分样本检验等方法,分析学生干部经历对大学生连续创业行为的影响及其作用机制。研究发现:学生干部经历能显著促进大学生连续创业行为的发生;信息资本的中介效应存在,即学生干部经历通过促进大学生信息资本积累,进而对其连续创业行为产生积极作用;学生干部经历的连续创业行为促进效应具有延时性,对毕业生的影响较在校生更大。为此,高校既需要从学生干部岗位数量和内容两方面入手丰富大学生的学生干部经历,又需要加强创业政策宣传增加大学生创业信息资本的积累。

关键词：大学生创业者学生干部经历连续创业行为创新创业信息资本人力资本

集成深度强化学习在股票指数投资组合优化中的应用分析

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计算机科学与探索 2025年第01期19卷 237-244页

作者：冀中张文嘉天津大学电气自动化与信息工程学院天津大学佐治亚理工深圳学院

基于集成深度强化学习的投资组合选择是当前量化金融领域的关键技术之一。然而，目前采用上一窗口阶段最优指标决定下一阶段代理的集成滚动窗口方法存在一定的滞后性。为了有效应对这一不足，提出了双层嵌套集成深度强化学习方法。该方... 详细信息

基于集成深度强化学习的投资组合选择是当前量化金融领域的关键技术之一。然而，目前采用上一窗口阶段最优指标决定下一阶段代理的集成滚动窗口方法存在一定的滞后性。为了有效应对这一不足，提出了双层嵌套集成深度强化学习方法。该方法对三种代理（优势演员-评论员、深度确定性策略梯度和近端策略优化）进行两层嵌套模式，第一层集成通过最优化夏普比率进行阶段模型选择，第二层通过加权投票的方法集成三种深度强化学习算法，从单次训练中收集多个模型快照，在训练期间利用这些模型进行集成预测。分别对上证50投资指数和道琼斯指数及其包含的股票进行了投资组合研究，将持有指数被动策略和均值方差投资组合策略作为基线策略。实验采用了投资组合价值、年化回报率、年化波动率、最大回撤和夏普比率等指标作为对比指标。结果表明，所提出的集成方法在实用性和有效性上表现出较好的性能。

关键词：股票投资组合交易策略深度强化学习双层嵌套集成深度强化学习方法集成学习

INTERMETALLICS AS SUBSTITUTES FOR SUPERALLOYS

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 463-467页

作者： j. Zhang D. Feng Z. Y. zhong High Temperature Materials Division Central Iron and Steel Research Institute Beijing 100081China

The application advances of TiAl, Ti3Al and Ni3Al base aUoys were denumstrated by Central Iron and Steel Research Institute, China. The recent research progresses on improving the reliability of cast TiAI were mainly presented and discussed. The characteristics of the self-oriented lamellar microstructure in cast TiAI were investigated in both as cast and as HlPed states. Based on the mechanical anisotropy of the cast lamellar microstructure, the component specific microstrueture design was proposed for a better performance and reliability of cast TiAl.

关键词： intermetallic application TiAl alloy microstructure design