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environmental characteristics of sandstorm of Minqin Oasis in China for recent 50 years

Journal of environmental Sciences 2005年第5期17卷 857-860页

作者： ZHANG Ke-cun QU Jian-jun ZU Rui-ping FANG Hai-yan Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute. Chinese Academy ofSciences Lanzhou 730000 China

The purpose of this present study is to investigate the frequency and variation of sandstorm in Minqin Oasis. Using daily observational data of sandstorm and other meteorologic data from 1954 to 2000, we have illuminated the relationship between sandstorm, meteorological parameters and human activities. The results of the analysis show that the highest frequency of sandstorms occurrence and their duration mainly focus on March, April and May, especially in April. Most of sandstorms occur from midday to nightfall, but relative few appear from midnight to forenoon, which apparently correlates to the daily variations of atmospheric thermal stability within atmospheric boundary layer. Monthly mean and annual mean duration of sandstorms coincide well with the frequencies of sandstorm occurrence.

关键词： Minqin Oasis sandstorm environmental characteristics

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Physicochemical and environmental characteristics of alkali leaching residue of wolframite and process for valuable metals recovery

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Transactions of Nonferrous Metals Society of China 2022年第5期32卷 1638-1649页

作者： Yuan-lin CHEN Xue-yi GUO Qin-meng WANG Qing-hua TIAN Jin-xiang ZHANG Shao-bo HUANG School of Metallurgy and Environment Central South UniversityChangsha 410083China Ganzhou Nonferrous Metallurgy Research Institute Ganzhou 341000China Changsha Research Institute of Mining and Metallurgy Co. LTDChangsha 410012China

Physicochemical and mineralogical characteristics of an alkali leaching residue of wolframite were studied by XRD,SEM−EDS,chemical phase analysis,mineral liberation analyzer(MLA),and TG−DSC *** leaching tests,toxicity characteristic leaching procedure(TCLP)tests and Chinese standard leaching tests(CSLT)were conducted to determine the environmental mobility of toxic *** results show that,due to the high contents of W,Fe,Mn,Sn,and Nb,the residue is with high resource value,but the content of a toxic element,As,is also *** existing minerals of the investigated elements mainly occur as monomer particles,but it is difficult to extract these valuable metals by conventional acid leaching due to their mineral *** release of As increases over time in acidic *** leaching concentration of all investigated harmful elements through TCLP is within the limiting value,while the leaching concentration of As through CSLT exceeds the limiting value by more than 4 times,so the residue is classified as hazardous solid waste based on the Chinese standard.A process for valuable metals recovery from this residue was *** experimental results indicated that the main valuable metals could be extracted effectively.

关键词： alkali leaching residue physicochemical characteristics environmental characteristics valuable metals recovery

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Analysis and Zonation of Freeze–Thaw Action in the Chinese Plateau Region Considering Spatiotemporal Climate characteristics

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Engineering 2024年第11期42卷 308-325页

作者： Tiejun Liu Ming Zhang Dujian Zou Jiaping Liu Jinping Ou School of Civil and environmental Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China Guangdong Provincial Key Laboratory of Intelligent and Resilient Structures for Civil Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China School of Materials Science and Engineering Southeast UniversityNanjing 211189China

Concerns about the durability of transportation infrastructure due to freeze-thaw(F-T)cycles are particu-larly significant in the Chinese plateau region,where concrete aging and performance deterioration pose substantial *** current national standards for the frost resistance design of concrete struc-tures are based predominantly on the coldest monthly average temperature and do not adequately address the comprehensive effects of the spatiotemporal variance,amplitude,and frequency of F-T *** address this issue,this study introduced a spatiotemporal distribution model to analyze the long-term impact of F-T action on concrete structures by employing statistical analysis and spatial inter-polation *** analysis was applied to create a nationwide zonation of F-T action level from data on the freezing temperature,temperature difference,and the number of F-T ***,this study explored the similarity between natural environmental conditions and laboratory-accelerated tests using hydraulic pressure and cumulative damage theories.A visualization platform that incorporates tools for meteorological data queries,environmental characteristic analyses,and F-T action similarity calculations was *** research lays theoretical groundwork and provides technical guidance for assessing service life and enhancing the quantitative durability design of concrete structures in the Chinese plateau region.

关键词： Concrete durability Freeze-thaw(F-T) environmental characteristics Similarity Zonation

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Erosion environment in the sediment-rich area on the Loess Plateau

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Journal of Geographical Sciences 2002年第1期12卷 49-57页

作者： JIAO Ju-ying, LI Jing, WANG Wan-zhong (Institute of Soil and Water Conservation, CAS and Ministry of Water Resources Northwest Sci-techonology University of Agriculture and Forestry, Yangling 712100, China) Northwest Sci-techonology University of Agriculture and Forestry Institute of Soil and Water Conservation CAS and Ministry of Water Resources Yangling China (GRID:grid.458510.d) (ISNI:0000 0004 1799 307X)

Based on the investigation and analysis of characteristics of precipitation, natural environment, socio-economic factors and soil erosion, this paper indicates that the precipitation is the main driving force for the soil erosion in the sediment-rich area, its variability determines the characteristics of soil and water loss; the natural conditions such as the drainage systems, geological and topographic features, the composition of soil and land surface materials, vegetation and climate determine the seriousness of soil and water loss; irrational socio-economic activities of human beings usually accelerated soil and water loss; meanwhile, the low preservation rate and inferiority of soil and water conservation measures made it impossible to make rapid progress on soil and water loss control. Furthermore, the characteristics of erosion environment endowed this area with more sediment that is the main reason for the flooding disasters by the Yellow River. Therefore, more emphasis should be placed on the enhancement of soil and water conservation. The soil loss prediction models will provide scientific basis for the planning of soil and water conservation, the designing of soil and water conservation measures and the valuation of effects of soil and water loss control. According to the analysis of the previous studies on soil loss prediction, and the water-sediment variation features, it is thought that study on soil loss prediction under various rainfall conditions and soil-water conservation measures should be carried out.

关键词： Loess Plateau sediment-rich area soil erosion environmental characteristics

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Analysis of a Large-Scale Strong Convective Weather under a Weak Water Vapor Condition in Shanxi, China in Spring

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Journal of Geoscience and Environment Protection 2023年第7期11卷 165-180页

作者： Jingyu Hao Guixiang Zhao Jie Zhu Yang Wang Yanzhi Ma Yuanyuan Guo Shanxi Meteorological Observatory Taiyuan China Shanxi Meteorological Service Center Taiyuan China

This article uses NCEP 1° × 1° grid point reanalysis data, conventional meteorological observation data, FY2G satellite TBB data, radar combined reflectivity data, ground-encrypted automatic station observation data, etc., through the synoptic diagnostic analysis method for a comprehensive analysis of a large-scale underreporting of a strong convective weather process under weak water vapor conditions on the 13th April 2017. The results show that the severe convective weather process is affected by the short-wave disturbance in the northwesterly airflow, triggered by the uplift of the westerly trough, the mid-low shear line and the mesoscale front of the boundary layer in the dry northwest. The jet stream is also an important system for the development of this strong convective weather. In the case of weak water vapor and energy conditions, if there is strong dynamic uplift, vertical wind shear and large temperature differences, strong convection can still occur;the convection occurrence area corresponds to the high potential vorticity abnormal area. The movement speed and direction of the cloud cluster are also consistent with the movement of the high potential vorticity anomaly area;the potential vorticity anomaly will cause the cyclonic circulation to increase, and the upward movement will also increase, which is conducive to the development of strong convective weather. According to the position of the dew point front in the β mesoscale, the ground cold pool corresponds to the small value area of the convective cloud cluster TBB. The front of the cold pool is accompanied by a mesoscale ground convergence line, and the uplift is strengthened, which is conducive to the development and forward movement of thunderstorms;the outflow of the cold pool is guided by 700 hPa. When the wind direction is the same, the movement speed will increase, and the stronger the outflow, the faster the movement speed.

关键词： Strong Convection Mesoscale Boundary Layer Front Potential Vorticity environmental characteristics Maintenance and Evolution

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Analysis on characteristics of Architectural Environment of Traditional Villages in Southwest Mountainous Area:Taking Heijing Ancient Town of Chuxiong as an Example

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Asian Agricultural Research 2022年第2期14卷 36-38页

作者： Yannan LU College of City Construction Jiangxi Normal University Nanchang 330022 China

The formation of the ancient town of Heijing conforms to the natural conditions and local conditions,and makes effective use of the natural mountains,water bodies,trees and other resources of the ancient town,so that the ancient town and nature rely on each other and unify *** the analysis of the environmental characteristics of the ancient town,this paper further explores its cultural connotation.

关键词： Southwest mountainous area Heijing ancient town environmental characteristics Adaptation to local conditions

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