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Condition evaluation of a unique mining site

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International Journal of Mining Science and Technology 2015年第6期25卷 1023-1029页

作者： liu junsheng Chen Frank Y. Ma Yan Zhang Siya Civil Engineering Academy Xi’an University of Architecture & Technology Shaanxi Academy of Building Research Institute of Architecture and Civil Engineering Taiyuan University of Technology Department of Civil Engineering 777 W Harrisburg Pike The Pennsylvania State University

The primary objective of this study was to evaluate the existing conditions and the stability of a mining site in which the unique features of seismicity, mining activity, hydrological conditions, geological conditions, environmental conditions, and future development plans were considered. In particular, the potential subsidence locations near the proposed construction site, the effects of mining boundary profile,and the influence scope of the mining activity on the neighboring areas were investigated using the finite element method. The study results indicate:(1) the overlying sandstone layer to the coal layer is the key to the stability of the mining roof;(2) the broken boundary has the most effect, followed by the arc boundary and linear boundary;(3) the safe distance from the mining boundary should be at least400 m if the proposed structure is to be built near an active mining site. Other relevant engineering recommendations are also proposed. The concluded results from this study may serve as a guide to other similar sites in the world.

关键词： MiningStabilityConditionEvaluationFinite element

Unraveling atomistic and electronic origins of multiaxial magnetic anisotropy

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 175-182页

作者： Boyu liu Xueyang Li junsheng Feng Changsong Xu Hongjun Xiang Key Laboratory of Computational Physical Sciences(Ministry of Education) Institute of Computational Physical SciencesState Key Laboratory of Surface Physics and Department of PhysicsFudan UniversityShanghai200433China Shanghai Qi Zhi Institute Shanghai200030China School of Physics and Material Engineering Hefei Normal UniversityHefei230601China

Multiaxial magnetic anisotropy(MA)refers to the phenomenon that multiple axes of the magnetic crystal correspond to different energy *** with the common uniaxial magnetic anisotropy,multiaxial MA facilitates novel forms of applications in ***,by combining the first-principles-based spin Hamiltonian and tight-binding(TB)method,we reveal the microscopic origins,instead of the common phenomenological understanding,of biaxial MA and triaxial *** the example system of NiO,it is found that the multiple minima result from the fourth-order and the sixth-order single ion interactions,while the difference between[110]and[110]directions originates from a second-order bond-dependent anisotropic pair interaction(i.e.,the so-called Gamma interaction).Moreover,through the application of a newly developed general spin dependent TB approach,it is revealed that the triaxial MA arises from the special spin-orbital entangled Hund term,which is different from the orbital-independent Hund term in the usual Slater Koster TB *** work thus not only leads to a thorough understanding of the multiaxial MA in NiO,but also establishes a methodology that can be widely used to explore the microscopic origins of MA in different magnets.

关键词： multiaxial magnetic anisotropy origin of multiaxial magnetic mnisotropy effective spin Hamiltonian tight-binding model antiferromagnetism

Volatiles profiles and factors affecting absorption of key odorants in Osmanthus black tea

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Food Quality and Safety 2024年第4期8卷 879-891页

作者： Binwei Dai Weixuan Chen Weihong Huang junsheng liu Bo Li Puming He Donald Grierson Youying Tu Yuanyuan Wu Department of Tea Science Zhejiang UniversityHangzhouChina Zhejiang Provincial Department of Agriculture and Rural Affairs HangzhouChina Plant and Crop Sciences Division School of BiosciencesUniversity of NottinghamLoughboroughUK Zhejiang Provincial Key Laboratory of Horticultural Plant Integrative Biology Zhejiang UniversityHangzhouChina

Objectives:Osmanthus black tea(OBT)is produced by reprocessing black tea while it absorbs the fragrance of Osmanthus fragrans and this scenting process is crucial for forming the unique aroma of *** work intended to reveal the effects of scenting parameters,the types of base tea,and scenting technologies on the aroma quality of *** and Methods:In this study,volatile compounds of OBTs with different scenting parameters,types of base tea,and scenting technologies were analyzed by solid-phase microextraction and gas chromatography-mass *** gene co-expression network analysis and orthogonal partial least squares discriminant analysis were used to identify the key volatile compounds of ***:More than 80 volatile compounds of OBT were found,and six compounds,α-ionone,β-ionone,γ-decalactone,dihydro-β-ionone,dihydro-β-ionol,and 6-pentyl-2-pyrone,were identified as the key volatiles of *** scenting time(ST)increased,the key volatile compounds in OBT showed an upward trend or increased initially and then ***,the contents of key volatile compounds increased as the ratio of flowers to tea(RFT)*** addition,base teas with a high proportion of pekoes produced higher-quality OBT by absorbing more key volatile compounds from *** OBTs made from the fast-scenting process and the traditional scenting process(TS),showed that higher aroma quality was obtained through repeated scenting rounds of ***:Appropriate long ST and high RFT,as well as base tea with a high proportion of pekoes and TS with repeated scenting rounds are beneficial for the accumulation of odorants and the improvement of aroma quality in OBT.

关键词： Osmanthus black tea scenting technology volatile compounds aroma quality

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FTAAP Is Expected

Beijing Review 2014年第46期57卷 18-19页

作者： Shen Minghui liu junsheng the National Institute of International Strategy of the Chinese Academy of Social Sciences

In terms of economic scale and the number of regions included, Asia-Pacific Economic Cooperation （APEC） is one of the world＇s three major regional cooperation organizations together with the EU and the North American Free Trade Agreement. The annual APEC Economic Leaders＇ Meeting holds great significance for both the region and the world. The Free Trade Area of the Asia-Pacific （FTAAP） will represent a hot topic dudng this year＇s meetin~

关键词：自由贸易区自由贸易协定亚太经合组织 APEC 经济规模合作组织亚太地区大区域

Subjective Well-Being and Its Determinant from A Study of Beijing’s Urban Elderly

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心理科学 2003年第1期 8-11页

作者： Xiao JianE-mail:Jianx@*** Hu junsheng liu Cuixia (Department of Psychology,Beijing University,Beijing,100871)

This study was designed to obtain an understanding of the subjective well-being (SWB) status among China’s urban elderly, and to find out the major factors that could influence the status in question. Our survey was conducted of 233 urban elderly individuals, and the data was statistically examined by multiple regression analysis with the results that: 1) The SWB of China’s urban elderly was relatively high as only 4.5% of all respondents considered themselves unhappy or very unhappy; 2) Major factors that had an influence on SWB included economic resource, mobility, age and social support; and 3) Five demographic variables accounted for 18.6% of the variance in SWB, which was slightly higher than that of foreign findings. It is concluded that financial security, active participation in physical and social activities, and social support are necessary for the improvement of the SWB of the elderly.

关键词： subject well being elderly people.

Effects of minor Sc on the microstructure and mechanical properties of Al-Zn-Mg-Cu-Zr based alloys

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Rare Metals 2009年第1期28卷 102-106页

作者： LI Wenbin PAN Qinglin ZOU Liang LIANG Wenjie HE Yunbin liu junsheng School of Materials Science and Engineering Central South University Changsha 410083 China Department of Civil Engineering Hunan City University Yiyang 413000 China

Five kinds of Al-Zn-Mg-Cu-Zr based alloys with different Sc additions were prepared by ingot metallurgy. The effects of minor Sc on the microstructure and mechanical properties of Al-Zn-Mg-Cu-Zr based alloys were investigated using tensile tests, optical microscopy （OM）, and transmission electron microscopy （TEM）. The results show that the ultimate tensile strength and yield strength are improved by 94 and 110 MPa, respectively, and the elongation to failure remains at a reasonable extent （11.1%） in the Al-Zn-Mg-Cu-Zr based alloy with 0.21 wt.% Sc addition after solution heat treatment at 475°C for 40 min and then aged at 120°C for 24 h. The addition of minor Sc induces the formation of Al3（Sc,Zr） particles, which are highly effective in refining the cast microstructures, retarding recrystallization, and pinning dislocations. The increment of strength is attributed mainly to fine grain strengthening, precipitation strengthening of Al3（Sc,Zr） particles, and substructure strengthening.

关键词： aluminum alloy scandium ingot metallurgy microstructure mechanical properties

基于参数随机分布的潜流带地下水数值模拟研究

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人民黄河 2025年第2期47卷 107-112,155页

作者：王辉刘军生王荆赵寿刚孙瑞东王田野张一博兰雁杨浩明侯佼建河南省引江济淮工程有限公司河南商丘476200 黄河水利委员会黄河水利科学研究院河南郑州450003 水利部堤防安全与病害防治工程技术研究中心河南郑州450003 郑州大学水利与交通学院河南郑州450001

含水层水文地质参数的合理性是决定地下水数值模型模拟精度的关键因素之一。以淮河流域清水河典型河段为研究区,通过含水层土体野外监测和室内试验,建立了渗透系数、给水度和贮水率的概率密度分布函数,并利用参数中值和置信度为95%的置... 详细信息

含水层水文地质参数的合理性是决定地下水数值模型模拟精度的关键因素之一。以淮河流域清水河典型河段为研究区,通过含水层土体野外监测和室内试验,建立了渗透系数、给水度和贮水率的概率密度分布函数,并利用参数中值和置信度为95%的置信区间,建立了基于多参数概率密度分布的地下水数值模型。结果表明:相较于采用地质勘探建议值的传统地下水数值模型,基于多参数概率密度分布的地下水数值模型的地下水位模拟结果的精确度得到了显著提升;河流水位、河床渗透系数等直接影响河流与地下水之间的水量交换强度,以及地下水的渗流和储存特征。

关键词：地下水数值模拟参数随机分布清水河

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海上风电钢管桩石墨烯增强保护层的力学性能

建筑材料学报 2023年第4期26卷 412-418页

作者：许亮刘军升浙江华东工程咨询有限公司浙江杭州310000

为了改善海上风电浪溅区钢管桩保护层的力学性能,设计了一种石墨烯光敏复合增强纤维高性能树脂复合带作为保护层的中间层,采用损伤理论并考虑冲击荷载和温度荷载的影响,建立了数值模型以研究该保护层的力学性能,并与中间层为环氧玻璃钢... 详细信息

为了改善海上风电浪溅区钢管桩保护层的力学性能,设计了一种石墨烯光敏复合增强纤维高性能树脂复合带作为保护层的中间层,采用损伤理论并考虑冲击荷载和温度荷载的影响,建立了数值模型以研究该保护层的力学性能,并与中间层为环氧玻璃钢的保护层的力学性能进行了对比.结果表明:在相同冲击荷载作用下,石墨烯光敏复合增强纤维高性能树脂复合带发生损伤的临界荷载超过环氧玻璃钢的1.5倍;在相同温度下,石墨烯光敏复合增强纤维高性能树脂复合带中间层下表面的剪切应力不到环氧玻璃钢中间层的1/10.

关键词：海上风电石墨烯光敏复合增强纤维高性能树脂复合带环氧玻璃钢力学性能

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面向室内导航的分层认知路网优化方法

地球信息科学学报 2021年第9期23卷 1586-1597页

作者：王行风刘俊生中国矿业大学环境测绘学院徐州221116 南京市测绘勘察研究院股份有限公司南京210019

随着室内空间应用规模的增加以及室内定位技术的发展,面向大型场馆等室内空间的应急救援与导航成为室内GIS应用的研究热点,而室内路网构建是室内应急导航服务得以实现的关键技术。本文面向室内导航寻径的这一现实问题,以室内路网动态构... 详细信息

随着室内空间应用规模的增加以及室内定位技术的发展,面向大型场馆等室内空间的应急救援与导航成为室内GIS应用的研究热点,而室内路网构建是室内应急导航服务得以实现的关键技术。本文面向室内导航寻径的这一现实问题,以室内路网动态构建与优化作为研究对象,基于室内空间感知规律以及分层认知的方式,提出和构建了室内单元认知分层编码方法:①将建筑物室内路网分为街道-建筑物、建筑物-楼层、楼层-区块、区块-房间等4个层次;②为了满足语义分析的需求,在分析室内单元功能的基础上,引入“虚拟房间单元”,将室内封闭性空间和联系性空间统一剖分为房间单元;③依据室内建筑认知分层模型以及室内单元剖分结果,按照建筑物-楼层-分区-房间单元的顺序,从高级到低级的顺序进行连续分层编码。以国内某商业中心为例构建了室内分层认知路网,每一个层次都可以减少参与运算的结点和弧段数,简化了计算网络,从而提高了运算的效率,同楼层寻径时间约为55 ms,跨楼层的寻径时间约为100 ms左右。结果表明,该分层认知编码模型符合人们对室内路网的经验性层次认知,能够很好地刻画路网层次特征,能满足寻径计算的精度和效率的要求,为面向导航的室内应用奠定了基础。

关键词：室内地理信息系统空间认知分层认知拓扑关系路网模型寻径位置服务室内导航