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Arsenic and fluoride co-enrichment of groundwater in the loess areas and associated human health risks:A case study of Dali County in the Guanzhong Basin

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China Geology 2024年第3期7卷 445-459页

作者： Rui-ping Liu Fei Liu Hua-qing Chen Yu-ting Yang Hua Zhu you-ning xu Jian-gang Jiao Refaey M El-Wardany Xi'an Center China Geological SurveyMinistry of Natural ResourcesXi'an 710054China Observation and Research Station of Environmental Geology of Typical Mines in Shaanxi Province MNRXi'an 710054China Key Laboratory for Geo-hazards in Loess Area MNRXi'an 710054China Dalian Ocean and Fishery Comprehensive Administration Supervision Lochus Dalian 116000China Pingliang City Development and Reform Commission Pingliang 744000China School of Earth Science and Resources Chang’an UniversityXi'an 710054China Faculty of Science Al-Azhar UniversityAssiut 71524Egypt

This study aims to reveal the occurrence and origin of typical groundwater with high arsenic and fluoride concentrations in the loess area of the Guanzhong Basin—a Neogene faulted *** findings are as follows:(1)Groundwater samples with high arsenic and fluoride concentrations collected from the loess area and the terraces of the Weihe River accounted for 26%and 30%,respectively,of the total samples,with primary hydrochemical type identified as HCO_(3)-*** karst and sand areas exhibit relatively high groundwater quality,serving as preferred sources for water *** is recommended that local governments fully harness groundwater in these areas;(2)groundwater with high arsenic and fluoride concentrations in the loess area and the alluvial plain of rivers in Dali County is primarily distributed within the Guanzhong Basin,which represents the drainage zone of groundwater;(3)arsenic and fluoride in groundwater originate principally from natural and anthropogenic sources;(4)the human health risk assessments reveal that long-term intake of groundwater with high arsenic and fluoride concentrations pose cancer or non-cancer risks,which are more serious to kids compared to *** study provides a theoretical basis for the prevention and treatment of groundwater with high arsenic and fluoride concentrations in loess areas.

关键词： Arsenic Fluoride Groundwater Cancer risk Kid and adult Human health risk assessment Hydrogeological survey engineering Environmental geological survey engineering Loess areas

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Migration and speciation transformation mechanisms of mercury in undercurrent zones of the Tongguan gold mining area, Shaanxi Loess Plateau and impact on the environment

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China Geology 2021年第2期4卷 311-328页

作者： Rui-ping Liu you-ning xu Hui-chao Rui El-Wardany RM Ying Dong Xi’an Center of China Geological Survey Ministry of Natural ResourcesXi’an 710054China Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region Ministry of EducationXi’an 710054China Key Laboratory for Geo-hazards in Loess Area Ministry of Natural ResourcesXi’an 710054China Field Base of Scientific Observation of Shaanxi Tongguan Ministry of Natural ResourcesXi’an 710054China School of Earth Science and Land Resources Chang’an UniversityXi’an 710054China Al-Azhar University Assiut Branch 71524Egypt

In order to study the migration and transformation mechanism of Hg content and occurrence form in subsurface flow zone of gold mining area in Loess Plateau and its influence on water environment,the field in-situ infiltration test and laboratory test were carried out in three typical sections of river-side loess,alluvial and proluvial strata in Tongguan gold mining area of Shaanxi Province,and the following results were obtained:(1)The source of Hg in subsurface flow zone is mainly caused by mineral processing activities;(2)the subsurface flow zone in the study area is in alkaline environment,and the residual state,iron and manganese oxidation state,strong organic state and humic acid state of mercury in loess are equally divided in dry and oxidizing environment;mercury in river alluvial or diluvial strata is mainly concentrated in silt,tailings and clayey silt soil layer,and mercury has certain stability,and the form of mercury in loess is easier to transform than the other two media;(3)under the flooding condition,most of mercury is trapped in the silt layer in the undercurrent zone where the sand and silt layers alternate with each other and the river water and groundwater are disjointed,and the migration capacity of mercury is far less than that of loess layer and alluvial layer with close hydraulic connection;(4)infiltration at the flood level accelerates the migration of pollutants to the ground;(5)the soil in the undercurrent zone is overloaded and has seriously exceeded the *** the groundwater monitoring results are safe this time,relevant enterprises or departments should continue to pay attention to improving the gold extraction process,especially vigorously rectify the small workshops for illegal gold extraction and the substandard discharge of the three wastes,and intensify efforts to solve the geological environmental problems of mines left over from *** present,the occurrence form of mercury in the undercurrent zone is relatively s

关键词： Mercury speciation Hyporheic zones Constant surface water level Flood level Surface-groundwater Hydraulic connection Tongguan gold mining areas Loess Plateau Shannxi Province

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Effects of heavy metal pollution on farmland soils and crops:A case study of the Xiaoqinling Gold Belt,China

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China Geology 2020年第3期3卷 402-410页

作者： Rui-ping Liu you-ning xu Jiang-hua Zhang Wen-ke Wang Rafaey M Elwardany Xi’an center China Geological SurveyMinistry of Natural ResourcesXi’an 710054China Key Laboratory of Subsurface Hydrology and Ecological Effect in Arid Region of Ministry of Education Xi’an 710054China Key Laboratory for Geo-azards in Loess Area Ministry of Natural ResourcesXi’an 710054China Field base of scientific observation of Shannxi Tongguan Ministry of Natural ResourcesXi’an 710054China School of Environmental Science&Engineering of Chang’an University Xi’an 710054China School of Earth Science and Land Resources of Chang’an University Xi’an 710054China Faculty of Science Al-Azhar UniversityAssiut 71524Egypt

This paper focuses on the heavy metal enrichment and heavy metal pollution degree associated with mining activities in some crops and the soils of different parent materials in the Xiaoqinling Gold *** to the geochemical analysis results of the soils observed in the gold belt,the soils are most highly enriched in Pb,followed by Cr,Cu,and ***,they are relatively poor in Hg,Cd,and *** is also shown that the heavy metals in all kinds of soils have the same geochemical characteristics in the gold *** for the crops(such as corn and wheat)in the gold belt,Zn and Cu are the most abundant elements,followed by Pb and ***,Hg,Cd,and As were found to have relatively low concentrations in the *** heavy metals in wheat and corn have the same geochemical characteristics in the gold belt in *** to the aeolian loess soils and the crops therein,heavy metals are more enriched in diluvial and alluvial soils and the crops *** shown by relevant studies,the Hg,Pb,Cd,Cu,and Zn pollution are mainly caused by mining *** and wheat in the gold belt have a high tendency of risk exposure to heavy metal pollution since they are mostly affected by mining activities and feature high background values of heavy metal ***,wheat is more liable to be enriched in heavy metals than corn is grown in all types of *** Hg pollution in soils leads to Hg accumulation,increasing the risk of Hg uptake in crops,and further affecting human *** study will provide a scientific basis for the control and management of heavy metals in farmland soils of mining areas.

关键词： Heavy metal pollution Crops Farmland Environmental investigation engineering of soil Xiaoqinling Gold Belt China

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A Tiny Example Based Procedural Model for Real-Time Glinty Appearance Rendering

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Journal of Computer Science & Technology 2024年第4期39卷 771-784页

作者： you-Xin Xing Hao-Wen Tan Yan-ning xu Lu Wang School of Software Shandong UniversityJinan 250101China NetEase(Hangzhou)Network Co. LtdHangzhou 310052China

The glinty details from complex microstructures significantly enhance rendering ***,the previous methods use high-resolution normal maps to define each micro-geometry,which requires huge memory *** paper observes that many self-similarity materials have independent structural characteristics,which we define as tiny example *** propose a procedural model to represent microstructures implicitly by performing spatial transformations and spatial distribution on tiny ***,we precompute normal distribution functions(NDFs)by 4D Gaussians for tiny examples and store them in multi-scale NDF *** with a tiny example based NDF evaluation method,complex glinty surfaces can be rendered simply by texture *** experimental results show that our tiny example based the microstructure rendering method is GPU-friendly,successfully reproducing high-frequency reflection features of different microstructures in real time with low memory and computational overhead.

关键词： real-time rendering reflectance modeling glinty material photorealistic rendering microstructure

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Even-odd layer-dependent multiferroic in freestanding rare-earth orthorhombic perovskite

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 151-157页

作者： Shaowen xu Fanhao Jia ning Dai School of Physics and Optoelectronic Engineering Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China Department of Physics College of ScienceHangzhou Dianzi UniversityHangzhou 310018China State Key Laboratory of Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083China

Freestanding oxide perovskites possess strong interlayer coupling between adjacent atomic layers,thus exerting a determinative effect on the magnetism and ferroelectricity of these atomic-scale ***,we propose an effective strategy to manipulate magnetism and ferroelectricity in freestanding rare-earth orthorhombic perovskite via modulation of layer *** performing first-principles calculations,an even-odd oscillation is demonstrated in few-layer GdAlO_(3)perovskite(GAP).Specifically,odd-layer systems with charged atomic layers are ferromagnetic polar metals,while even-layer systems are antiferromagnetic ferroelectric *** thickness-dependent magnetic phase transition originates from carrier doping,as rationalized by the Stoner ***,we demonstrate the promotion of in-plane ferroelectricity via the concurrent application of two distinct antiferrodistortive displacements,each driven by formation and breaking of *** multiferroic phases may emerge in other transition metal oxide perovskites supporting multiple valence states,e.g.,few-layer Gd MO_(3)(M=V,Cr,Mn,and Ni).This work puts forward a strategy for layer thickness engineering of magnetism and ferroelectricity in 2D oxide perovskite multiferroic materials.

关键词： few-layer rare-earth perovskite multiferroicity size effect first principles calculations

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THE SYNTHESIS OF ZSM-35 WITH A NEW KIND OF TEMPLATING AGENT

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Chinese Chemical Letters 1993年第9期4卷 845-846页

作者： Tian you SONG Jia ning xu Yao Cai TONG Ru Ren xu Department of Chemistry,Jilin University,Changchun,130023

The present paper covers the synthesis of ZSM-35 molecular sieve with 1,6-hexanediamine as templating agent,the influence of the synthesis conditions, and a discussion concerning the crystal structures of the products.

关键词： THE SYNTHESIS OF ZSM-35 WITH A NEW KIND OF TEMPLATING AGENT AI OH US

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Comparison of Microwave Imaging Algorithms for Short-Range Scenarios

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Journal of Beijing Institute of Technology 2024年第3期33卷 227-236页

作者： Zhengyue Dong ning xu Kuiwen xu Engineering Research Center of Smart Microsensors and Microsystems Ministry of EducationHangzhou Dianzi UniversityHangzhou 310018China

Three dimensional(3-D)imaging algorithms with irregular planar multiple-input-multiple-output(MIMO)arrays are discussed and compared with each *** on the same MIMO array,a modified back projection algorithm(MBPA)is accordingly proposed and four imaging algorithms are used for comparison,back-projection method(BP),back-projection one in time domain(BP-TD),modified back-projection one and fast Fourier transform(FFT)-based MIMO range migration algorithm(FFT-based MIMO RMA).All of the algorithms have been implemented in practical application scenarios by use of the proposed imaging *** to the practical applications,MIMO array-based imaging system with wide-bandwidth properties provides an efficient tool to detect objects hidden behind a *** MIMO imaging radar system,composed of a vector network analyzer(VNA),a set of switches,and an array of Vivaldi antennas,have been designed,fabricated,and ***,these algorithms have been applied to measured data collected in different scenarios constituted by five metallic spheres in the absence and in the presence of a wall between the antennas and the targets in simulation and pliers in free space for experimental ***,the focusing properties and time consumption of the above algorithms are compared.

关键词： multiple-input-multiple-output(MIMO) short-range imaging back projection modi-fied back propagation range migration algorithm(RMA) through-wall imaging

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Microplastic pollution in surface water and sediments of Qinghai-Tibet Plateau: Current status and causes

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China Geology 2021年第1期4卷 178-184页

作者： Rui-ping Liu Ying Dong Guo-cang Quan Hua Zhu you-ning xua Rafaey M.Elwardany Xi’an center China Geological SurveyMinistry of Natural ResourcesXi’an 710054China Key Laboratory of Subsurface Hydrology and Ecological Effects in Arid Region Ministry of EducationXi’an 710054China Key Laboratory for Geo-hazards in Loess Area Ministry of Natural ResourcesXi’an 710054China Field Base of Scientific Observation of Shannxi Tongguan Ministry of Natural ResourcesXi’an 710054China Institute of Hydrogeology Engineering Geology and Environment Geology Survey of Qinghai ProvinceXining 810008China School of Earth Science and Land Resources of Chang’an University Xi’an 710054China Faculty of Science Al-Azhar UniversityAssiut 71524Egypt

To study the current status and causes of the microplastic pollution in surface water of the Qinghai-Tibet Plateau,this paper compared the average microplastic abundance in sediments and surface water of the Qinghai-Tibet Plateau and the results are as ***,the average microplastic abundance in surface water of the independent rivers and the whole area is 247−2686 items/m^(3) and 856 items/m^(3),*** average microplastic abundance in sediments of independent rivers or lakes and the whole area is 0−933 items/m^(2) and 362 items/m^(2),***,the degree of microplastic pollution in river sediments is higher than that in lake sediments,and the rivers suffering from microplastic pollution mainly include the Brahmaputra River,Tongtian River,and Nujiang ***,compared with the microplastic pollution in other areas of the world,the levelof microplastic pollution in the lakes and rivers of the Qinghai-Tibet plateau is not lower than that of well-developed areas with more intensive human ***,this study suggests that relevant government departments of the Qinghai-Tibet Plateau should strengthen waste management strategies while developing tourism and that much attention should be paid to the impacts of microplastics in the water environment.

关键词： Microplastic pollution Microplastic abundance Surface water River sediment Water environment Human activities Qinghai-Tibet Plateau China

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Empirical model of concrete block fragment behavior under explosion loads

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Science China(Technological Sciences) 2024年第8期67卷 2515-2529页

作者： YANG Shuai ning JianGuo REN HuiLan xu XiangZhao State Key Laboratory of Explosion Science and Safety Protection Beijing Institute of TechnologyBeijing 100081China

Concrete structures undergo integral fragmentation under explosion loads. The fragmentation degree and particle-size distribution of concrete blocks under explosion loads must be considered during mining to ensure safety. In this study, the impulse is calculated based on the relationship between overpressure and time, and the impact energy of the explosion wave is obtained based on blast theory. Subsequently, the Mohr-Coulomb shear strength fracture criterion is introduced to determine the ultimate shear stress of the concrete materials, and an empirical model that can effectively calculate the energy consumption of concrete blocks under explosion loads is established. Furthermore, concrete fragments with different particle sizes under explosion scenarios are quantitatively predicted with the principle of energy conservation. Finally, explosion tests with different top standoff distances are conducted, and the concrete fragments after the explosion tests are recovered, sieved, weighed, and counted to obtain experimental data. The effectiveness of the fragment empirical model is verified by comparing the model calculation results with the experimental data. The proposed model can be used as a reference for civil blasting, protective engineering design, and explosion-damage assessment.

关键词： concrete structures explosion loads fragment behavior empirical model

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Effect of fore/aft-loaded rotor on compressor stability under inlet circumferential distortion

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Chinese Journal of Aeronautics 2024年第5期37卷 199-213页

作者： Dakun SUN Benhao GU Fangfei ning Dengke xu Xiaofeng SUN School of Energy and Power Engineering Beihang UniversityBeijing 102206China Research Institute of Aero-engine Beihang UniversityBeijing 102206China

A modified small perturbation stability prediction model for axial compressors with circumferential inlet distortions is established and applied to investigate the effect of fore/aft-loaded rotor on compressor stability under circumferentially distorted inlet *** inlet total pressure distribution downstream of the distortion screen is measured in experiments and employed for simulations which are implemented via time-space spectral *** stall inception prediction results via the stability model indicate that the compressor with aft-loaded rotor not only performs better in terms of stability under uniform inlet,but also maintains a larger stability margin under circumferentially distorted *** experiments for compressors with fore-loaded and aft-loaded rotor are respectively carried *** results validate the reliability of numerical simulations and the predicted conclusion that the aft-loaded rotor is beneficial for compressor ***,the ability of the developed theoretical model for compressor stability prediction under circumferential distortions is *** addition,dynamic pressure signals at rotor tip measured in experiments illustrate that the circumferential distortion has little effect on the compressor stall pattern.

关键词： Axial compressor stability Inlet distortion Blade loading Small perturbation Time-space spectral method

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