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Discussion on pile axial load test methods and their applicability in cold regions

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Research in Cold and Arid Regions 2022年第4期14卷 239-249页

作者： jiaWei Gao ji Chen Xin Hou QiHang Mei YongHeng Liu Beiluhe Observation and Research Station on Frozen Soil Engineering and Environment in qinghai-Tibet Plateau State Key Laboratory of Frozen Soil EngineeringLanzhouGansu730000China University of Chinese Academy of Sciences Beijing100049China

The measurement of pile axial load is of great significance to determining pile foundation design parameters such as skin friction and end bearing capacity and analyzing load transfer *** by the temperature and ice content of frozen ground,the interface contact relationship between pile foundation and frozen soil is complicated,making pile axial load measurements more uncertain than that in non-frozen ***,it is necessary to gain an in-depth understanding of the current pile axial load test *** methods are systematically reviewed:vibrating wire sensors,strain gauges,sliding micrometers,and optical fiber strain *** the same time,the applicability of the four test methods in frozen soil regions is discussed in *** first two methods are mature and commonly *** sliding micrometer is only suitable for short-term *** the Fiber Bragg grating(FBG)strain gauge meets the monitoring requirements,the Brillouin optical time-domain reflectometer(BOTDR)needs further *** paper aims to provide a technical reference for selecting and applying different methods in the pile axial load test for the stability study and bearing capacity assessment of pile foundations in cold regions.

关键词： Pile axial load Test methods Pile shaft resistance Sensors Cold regions

Comparative Study on Mineral Elements in the Roots of Rheum tanguticum from qinghai-Plateau

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光谱学与光谱分析 2011年第3期31卷 812-815页

作者： LI jin-ping HAN You-ji LIU Li-kuan LI Tian-cai SUN jin CHEN Gui-chen Northwest Institute of Plateau Biology Chinese Academy of Sciences Xinjing 810008 China Key Laboratory of Environment and Resources on Tibetan Plateau Ministry of Education Qinghai Normal University Xining 810008 China Graduate University of Chinese Academy of Sciences Beijing 100049 China China Agricultural Vet-Bio Science and Technology Co. LTD. Lanzhou 730046 China

In the present paper,the authors analysed 10 mineral elements in the roots of Rheum tanguticum collected from 30 different *** mean concentration values of the 10 elements decreased as follows: Ca>Mg>K>Fe>Mn>Cr>Zn>Ni>Cu>Se. Ca,Mg,K and Fe were abundant in this *** elements varied over a wide range depending on the different *** mineral element data were evaluated by principal component analysis to reveal the distribution pattern of elements in *** principal components(K-Ca factor,Cu factor,Mg factor and Zn-Se factor) of plant elements were *** authors' study provided a new scientific foundation for further studies and general application of this Chinese herb.

关键词： Rheum tanguticum Maxim.ex Balf Mineral elements Principal component analysis(PCA) Different habitats

Analysis on phase selection and microstructure evolution in directionally solidified Zn-Al-Mg-Ce alloy

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China Foundry 2023年第4期20卷 347-355页

作者： ji-peng Li De-gao Qiao Shi-wen Dong Peng Peng Xian-tao Yan Xu-dong Zhang Gansu jiu Steel Group Hongxing Iron and Steel Co. Ltd.Jiayuguan 735199GansuChina School of Materials and Energy Lanzhou UniversityLanzhou 730000China School of Physics and Electronic Information Engineering Qinghai Normal UniversityXining 810016QinghaiChina

In the process of hot-dip Zn-Al-Mg alloy coating,the plating solution dissipates heat in the direction perpendicular to the steel plate,which is considered to be a process of directional *** understand the relationship between microstructure and cooling rate of Zn-Al-Mg alloys,both the phase constitution and microstructure characteristic length scales of Zn-9.5Al-3Mg-0.01Ce(wt.%)alloy were investigated by the directional solidification experiments at different growth velocities(V=40,80,160,250μm·s^(-1)).The experimental results show that the microstructure of directionally solidified Zn-9.5Al-3Mg-0.01Ce alloy is composed of primary Al dendrites and(Zn-Al-Mg2Zn11)ternary eutectics at the growth velocities ranging from 40 to 250μm·s^(-1).The primary Al dendrites are aligned regularly along the growth direction,accompanied with obvious secondary *** relationship between the microstructure length scale and the thermal parameters of solidification is obtained:λ1=374.66V-0.383,andλ2=167.5V-0.563(λ1is the primary dendrite arm spacing,andλ2 is the secondary dendrit arm spacing).In addition,through the interface response function(IRF)and the nucleation and constitutional undercooling(NCU),the phase selection of Zn-9.5Al-3Mg-0.01Ce is obtained:(Zn+Al+Mg2Zn11)ternary eutectics in the Zn-9.5Al-3Mg-0.01Ce alloy will be replaced by ternary eutectics(Zn+Al+MgZn2)when the growth rate is lower than 7.53μm·s^(-1).

关键词： Zn-Al-Mg alloy directional solidification microstructure length scale phase selection

The status evaluation of the permafrost environment along the Chaida'er-Muli Railway in southern Qilian Mountains in northern qinghai Province,China

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Journal of Mountain Science 2016年第12期13卷 2124-2134页

作者： CAO Wei SHENG Yu CHOU Ya-ling WU ji-chun LI jing WANG Sheng-ting State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences Key Laboratory of Disaster Prevention and Mitigation in Civil Engineering of Gansu Province Lanzhou University of Technology

Engineering construction has major influence on the permafrost *** paper analyzes the interaction between engineering construction and permafrost environment along the Chaidaer-Muli Railway(simply,CMR) based on the press-state-response(PSR) *** permafrost environmental system is divided into three subsystems,consisting of permafrost thermal stability,proneness to the freeze-thawing erosion and permafrost ecological *** subsystem considers its most important influencing *** Progression Method(CPM) is applied to calculate the current environment condition along the *** result indicates that:(1) as far as the thermal stability is concerned,most sections along the CMR are mainly concentrated in rank Ⅲ(fair situation),and a few in Ⅱ(good situation) and Ⅳ(bad situation),respectively;(2) for the proneness tothe freeze-thawing erosion,the entire railway route falls largely in rank Ⅱ(good situation);(3) along the CMR,the ecological fragility of the permafrost environment is in rank Ⅱ(good situation),or slightly fragile;(4) overall,the permafrost environments along the CMR are in rank Ⅲ(fair situation) or Ⅱcondition(good situation).In general,the permafrost environment along the CMR is *** is mainly because a series of active measures of protecting permafrost were taken for stabilizing the CMR foundation *** the one hand,we should try our best to minimize the influences that engineering activities have exerted on ecology and environment,on the other hand,the positive measures have made improvements to prevent the permafrost environment from deterioration.

关键词： Permafrost environment Press-stateresponse framework Catastrophe theory Chaida'erMu Railway Environmental impact

青海易地扶贫搬迁:成效、挑战及其后续帮扶措施——基于市(州)级数据的实证分析

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青海民族大学学报（社会科学版） 2024年第1期50卷 160-170页

作者：李书锋贺雨晴秦菊芳胡继亮中央民族大学北京100081 华中师范大学湖北武汉430079

易地扶贫搬迁后续帮扶工作的有效推进对于巩固青海省脱贫攻坚成果、推动三江源地区生态保护和建设工作具有重要的意义。利用青海省8个市(州)的易地扶贫搬迁数据,采用统计描述法,针对易地扶贫搬迁的成效、挑战以及帮扶措施展开研究。通... 详细信息

易地扶贫搬迁后续帮扶工作的有效推进对于巩固青海省脱贫攻坚成果、推动三江源地区生态保护和建设工作具有重要的意义。利用青海省8个市(州)的易地扶贫搬迁数据,采用统计描述法,针对易地扶贫搬迁的成效、挑战以及帮扶措施展开研究。通过严密分析,得到如下结论:青海省通过易地扶贫搬迁,改善了人民生活水平,促进了农业生产、就业和收入实现多元化,生活就业更加便利,社会保障更加坚实,生态环境显著改善。然而,还存在如下风险和挑战:财政兜底责任大、可持续性生计难以保障、社会治理困难重重、后续难度管理大等。基于此,提出后续帮扶措施:完善生态保护补偿机制、转化低保人口、做好后续帮扶与乡村振兴有效衔接工作、提升城镇化与就业能力、建设大数据平台及强化党建引领。

关键词：易地扶贫搬迁青海后续帮扶措施实证分析

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西宁市道路扬尘排放清单及时空分布特征

环境化学 2024年第4期43卷 1167-1176页

作者：肖扬姬亚芹王淼赵静琦高玉宗杨益杨夏微王冰冰李景丛晓晓南开大学环境科学与工程学院天津300350 西宁市生态环境局西宁810008 青海洁神环境科技股份有限公司西宁810000

本研究通过实地采样与调查获取活动水平及相关数据,采用排放因子法建立2018年西宁市道路扬尘排放清单.利用ArcGIS进行3 km×3 km的空间分配,分析了其时空分布特征,利用蒙特卡洛模拟分析了道路扬尘排放清单的不确定性.结果表明,2018年西... 详细信息

本研究通过实地采样与调查获取活动水平及相关数据,采用排放因子法建立2018年西宁市道路扬尘排放清单.利用ArcGIS进行3 km×3 km的空间分配,分析了其时空分布特征,利用蒙特卡洛模拟分析了道路扬尘排放清单的不确定性.结果表明,2018年西宁市道路扬尘PM_(2.5)和PM_(10)排放量分别为1904.10 t和8563.09 t,其中国道贡献率最高,分别为41.79%和39.74%.主要排放地区为大通县,贡献率分别为36.32%和35.47%.道路扬尘排放在全年各月出现差异,其中在6月出现最高值.蒙特卡罗模拟结果表明,在95%的概率分布范围内,西宁市2018年道路扬尘PM_(2.5)和PM_(10)不确定性范围为-26.49%—51.11%和-30.14%—30.06%.

关键词：道路扬尘排放清单时空分配不确定性分析西宁市

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Boron isotope geochemistry of Bangor Co Salt Lake(central Tibet):implications for boron origin and uneven mixing of lake water

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Acta Geochimica 2022年第5期41卷 731-740页

作者： Bin-Kai Li Mao-Yong He Hai-Zhou Ma Huai-De Cheng Lian-Min ji qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes Qinghai Institute of Salt LakesChinese Academy of Sciences810008 XiningQinghaiChina State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of Sciences710061 Xi’anChina University of the Chinese Academy of Sciences 100049 BeijingChina

Boron is an essential,widely used,micronutrient element and is abundant in salt lakes on the qinghai-Tibet *** origin and distribution of boron brine deposits on the qinghai-Tibet Plateau is an important foundation for B resource formation,evolution,and enrichment,which have long been the subject of *** boron isotope system is a sensitive geochemical tracer,making it useful for eff ectively and precisely tracking a wide range of geological processes and *** study investigates the major cations,[B],andδB values of samples(lake brine,river waters,and cold spring water)from the Bangor Co Lake which is a typical salt lake rich in boron in Tibet,*** are magnitude-scale diff erences in[B]among diff erent sample types:river samples

关键词： Tibet Bangor Co salt lake Boron isotope Origin Fractionation processes

Patterns of grassland community composition and structure along an elevational gradient on the qinghai–Tibet Plateau

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Journal of Plant Ecology 2022年第4期15卷 808-817页

作者： Xin Wang jiangling Zhu Shitao Peng Tianli Zheng Zhaoyu Qi jianbo Hu Chengjun ji State Key Laboratory of Grassland Agro-ecosystems College of Pastoral Agricultural Science and TechnologyLanzhou UniversityLanzhou 730020China Department of Ecology College of Urban and Environmental ScienceKey Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871China Environmental Science and Technology Research Center Tianjin Research Institute for Water Transport EngineeringM.O.T.Tianjin 300456China

Grasslands in the qinghai–Tibet Plateau play an important role in preserving ecological security and high biodiversity in this ***,the distribution of the composition and structure of plant community and the mechanism by which it maintains itself in this region are still poorly ***,we designed 195 grassland plots in 39 grassland sites along an approximately 1700 m elevation gradient on the Northeastern qinghai–Tibet *** found that the grassland community height decreased significantly with increasing elevation,whereas community coverage did not significantly *** increasing elevation,plant species richness(αdiversity)increased significantly,but the community variability(βdiversity)decreased *** constrained clustering analysis suggested that theα-andβ-diversity in the grasslands transformed gradually with elevation,and that three discontinuous points(based on community structure)were observed at elevation of 3640,4252 and 4333 *** equation modeling(SEM)indicated that the increase in precipitation and the decrease in temperature significantly positively influencedαdiversity,which was negatively correlated withβ*** results demonstrate a quantitative-to-qualitative change in the community composition and structure along this elevational gradient on the qinghai–Tibet Plateau.

关键词： alpha diversity beta diversity elevational gradient qinghai–Tibet Plateau discontinuous points

2021年西宁市宾馆、理发店空气中化学污染物状况及健康风险评估

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环境卫生学杂志 2024年第1期14卷 68-71,92页

作者：吉秀亮杨君胜谢晓媛郭学斌青海省疾病预防控制中心公共卫生科西宁810007

目的了解西宁市宾馆、理发店空气中苯、甲苯、二甲苯、氨及甲醛等化学污染物的污染状况及健康风险特征,识别可能存在有害物质,为西宁市公共场所卫生状况的改善与管理提供依据。方法2021年对西宁市18家宾馆、9家理发店空气中苯、甲苯、... 详细信息

目的了解西宁市宾馆、理发店空气中苯、甲苯、二甲苯、氨及甲醛等化学污染物的污染状况及健康风险特征,识别可能存在有害物质,为西宁市公共场所卫生状况的改善与管理提供依据。方法2021年对西宁市18家宾馆、9家理发店空气中苯、甲苯、二甲苯、氨及甲醛进行监测,采用健康风险评价方法评价宾馆、理发店空气中化学污染物对从业人员的非致癌和致癌风险。结果2021年西宁市宾馆、理发店空气中苯、甲苯、二甲苯、氨均未超标,慢性非致癌效应的危害系数(hazard quo-tient,HQ)均低于1。甲醛致癌风险值高于1×10^(-4),苯的致癌风险值略高于1×10^(-6)。结论西宁市宾馆、理发店空气中氨、苯、甲苯和二甲苯暴露量未超过不良反应阈值,非致癌风险较低;甲醛、苯对人群具有潜在的致癌风险。

关键词：公共场所化学污染物风险评估