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Journal of Environmental Sciences 2022年第9期34卷 11-22页

作者： Yongjiang Zhang Tao Sun Ming Ma Xun Wang Qing Xie Cheng Zhang Yongmin Wang Dingyong Wang College of Resources and Environment Southwest UniversityChongqing 400715China Department of Environment and Quality Test Chongqing Chemical Industry Vocational CollegeChongqing 401220China School of Agricultural Sciences Zhengzhou UniversityZhengzhou 450001China

Manganese(Mn) ores contain substantial concentrations of mercury(Hg), and mining and smelting of Mn ores can bring Hg into the surrounding aquatic environment through atmospheric deposition, leaching of electrolytic Mn residue and Mn gangue dump. However, limited is known that how these processes influence the environmental behaviors of Hg in waterbody. Therefore, the seasonal distribution and existing form of Hg in water and sediment in one Mn ore area in Xiushan County, Chongqing were investigated. Our results showed that the mean Hg and methylmercury(Me Hg) concentrations in water( n = 35) were 5.8 ± 4.6 ng/L and 0.22 ± 0.14 ng/L, respectively. The mean Hg concentrations in retained riverbed and fluvial bank sediment( n = 35) were 0.74 ± 0.26 mg/kg and 0.63 ± 0.27 mg/kg, respectively(the mean Me Hg concentrations were 0.64 ± 0.40 μg/kg and 0.51 ± 0.30 μg/kg, respectively). It indicated that the mining and smelting of Mn ores were the main sources of anthropogenic Hg, and Mn may inhibit Hg methylation in rivers in Mn ore areas. Mercury in the bound to iron/Mn(Fe/Mn) oxides of low crystallinity fraction(Hg-OX) accounted for 4.01% and 5.25% of the total Hg concentrations in the retained riverbed and fluvial bank sediment, respectively. The amount of Hg bound to Fe/Mn oxides in sediment increased significantly due to the manganese mining activities in the investigated area. Therefore, it could be hypothesized that high Hg concentrations in river sediment in Mn mining areas are closely related to high Mn concentration in sediment.

关键词： Mn mining area Hg MeHg distribution characteristics Fractionation of Hg

Satellite breakup behaviors and model under the hypervelocity impact and explosion:A review

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Defence Technology(防务技术) 2023年第9期27卷 284-307页

作者： Si-yuan Ren Zi-zheng Gong Qiang Wu Guang-ming Song Qing-ming Zhang Pin-liang Zhang Chuan Chen Yan Cao Beijing Institute of Spacecraft Environment Engineering China Academy of Space TechnologyBeijing100094China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

The primary causes of satellite breakups are hypervelocity impact and explosion,the research on satellite breakup can be used not only to evaluate the influence of breakup event on the space environment,but also to trace whether the satellite has been deliberately *** is of great significance in both civil and military *** study of satellite breakup behaviors and model is reviewed to summarize the research progress and insufficiency in recent decades,including the satellite breakup experiment,measurement and characterization of fragments,distribution characteristics of breakup fragments,satellite breakup model,*** classical studies are introduced in detail,and the limitations of the current research are pointed *** to the current research results,the contemporary challenges and future directions for satellite breakup study are *** research on satellite breakup is developing in two directions:the miniaturization of satellite size and the complexity of satellite *** study on satellite breakup needs to be explored and deepened on improving the experimental launch speed,expanding the model application range and breakup revealing the results under combined effect of impact and explosion.

关键词： Satellite breakup Space environment distribution characteristics Hypervelocity impact Explosion

Seasonal distribution of Observed Colored Dissolved Organic Matter(CDOM)in the Eastern Indian Ocean

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Journal of Ocean University of China 2023年第4期22卷 886-896页

作者： CAI Xiaoqing MENG Jie YUAN Chao LIU Rongjie HOU Erhu BI Dayong LI Yaoru QIAN Chengcheng ZHONG Shan Shandong Key Laboratory of Marine Ecological Environment and Disaster Prevention and Mitigation Qingdao 266061China North China Sea Marine Forecasting Center Ministry of Natural ResourcesQingdao 266061China National Ocean Technology Center Ministry of Natural ResourcesTianjin 300112China The First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China North China Sea Environmental Monitoring Center Ministry of Natural ResourcesQingdao 266033China

Colored dissolved organic matter(CDOM)is a crucial constituent that affects the optical absorption properties of *** to the relatively limited measured data on the spatial distribution characteristics of CDOM in the tropical eastern Indian Ocean,this study analyzes the optical absorption characteristics of CDOM in the southeast Indian Ocean using the data collected during four seasons from 2013 to *** work also systematically describes the seasonal horizontal and vertical distribution characteristics of CDOM in this area and conducts a preliminary analysis of the relevant factors affecting CDOM absorption characteristics in this *** indicate that the CDOM ag(440)during summer was remarkably lower than that in the coastal waters of Europe and coastal waters of China but slightly higher than that in the western and southeast *** spatial distribution of surface CDOM shows remarkable seasonal differences,and the spatial distribution characteristics of CDOM in the 5°S,92°E region differ between spring/summer and autumn/*** values of ag(400)and ag(440)are weak/strong at a surface/subsurface level of 100 m,with differences found between summer and *** correlation of CDOM with temperature,salinity,and chlorophyll-a concentration is relatively low,indicating that CDOM is an independent driving mechanism influenced by phytoplankton degradation,photobleaching,and water mixing.

关键词： colored dissolved organic matter tropical eastern Indian Ocean distribution characteristics influencing factors

Summer Extreme Precipitation in the Key Region of the Sichuan-Tibet Railway

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Advances in Atmospheric Sciences 2023年第5期40卷 843-855页

作者： Jiali MA Xiuping YAO State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China University of Chinese Academy of Sciences Beijing 100049China China Meteorological Administration Training Centre Beijing 100081China

The Sichuan-Tibet Railway,mainly located in the southeastern Qinghai-Tibet Plateau,is affected by summertime extreme precipitation(SEP).Using daily rain-gauge observations and ERA5 reanalysis data for the summers of 1979-2020,the spatiotemporal distribution characteristics of SEP in the key region of the Sichuan-Tibet Railway(28°-33°N,90°-105°E,hereafter KR)are revealed,and the mechanism for SEP amount(SEPA)variation in the KR is *** results show that SEPA in the KR contributes nearly 30%to the total summer *** differences are evident in SEP,justifying thresholds higher in the plateau-dominated central-western KR(CWKR)and lower in the basindominated eastern KR(EKR).In addition,SEP in the CWKR is less intense but more frequent than SEP in the *** 1979-2020,the SEPA in the KR increased slightly while the SEPA in the CWKR increased significantly and peaked in the last *** anticyclonic circulation(AC)anomalies dominate the 500 hPa pattern over the Bay of Bengal and Mongolia,the southerly flow and cyclonic shear over the southeastern plateau will be strengthened,favoring more SEPA in the *** an AC anomaly dominates the 500 hPa pattern over the Bohai Sea,the low-level easterly wind over the basin will be strengthened,favoring more SEPA in the *** strengthening of the ascent,water vapor convergence,and convective instability is conducive to more SEPA in the *** results deepen the understanding of the characteristics and the physical mechanisms responsible for extreme precipitation in the KR.

关键词： summertime extreme precipitation distribution characteristics variation mechanism

distribution Patterns of Synechococcus Indicated Their Environmental Constraints and Related Geochemical Processes in the Yellow Sea

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Journal of Ocean University of China 2022年第2期21卷 499-508页

作者： ZHOU Yuting WANG Ting CHEN Xi QIN Song ZHAO Zhenjun GUO Xinyi LI Jialin Yantai Institute of Coastal Zone Research Chinese Academy of SciencesYantai 264000China College of Life Sciences Yantai UniversityYantai 264000China College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China College of Marine Life Science Ocean University of ChinaQingdao 266005China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China

Synechococcus is a widely distributed photosynthetic pico-phytoplankton,which contributes mainly to carbon fixation and maintains the stability of the marine *** investigate its distribution patterns in the Yellow Sea,seawater samples were collected during September *** of flow cytometry analysis showed that the Synechococcus abundance ranged from 6.36×10^(2) to 4.51×10^(4) cells mL^(−1),which correlated with salinity(Pdistribution correlated with temperature-salinity and nitrite in the Yellow Sea,and their geochemical function showed diverse but should be further verified in the future.

关键词： Synechococcus distribution characteristics environmental constraints co-occurrence network analyses the Yellow Sea

移动互联网时代“网红空间”分布特征研究--以杭州市主城区为例

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China City Planning Review 2022年第2期31卷 40-52页

作者：项婧怡罗震东张吉玉 School of Architecture and Urban Planning Nanjing University Spatial Planning Research Center Nanjing University Institute of Scientific and Technical Information of China

As a new visual consumer space,the“Internet-famous space”provides a new perspective for the study on urban space in the mobile Internet *** on the data of the Douyin(the Chinese version of Tiktok)platform,this paper quantitatively measures the popularity and the distribution characteristics of Internet-famous spaces in the main urban area of *** is concluded that the distribution of Internet-famous spaces shows a spatial pattern of multi-core concentration,with spatial popularity decreasing from the urban center to the *** hot spot areas of Internet-famous spaces are mainly distributed in the functional nodes of the city,and the concentration characteristics of the internal spaces in these different areas show great differences.

关键词： Internet-famous space Douyin spatial popularity distribution characteristics Hangzhou City

Investigation of groundwater characteristics and its influence on Landslides in Heifangtai Plateau using comprehensive geophysical methods

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Journal of Groundwater Science and Engineering 2023年第2期11卷 171-182页

作者： Feng-dan Yu Gang Qiao Kai Wang Xu Zhang Key Laboratory for Groundwater and Ecology in Arid and Semi-arid Areas Xi’an 710054China Xi’an Center of Geological Survey China Geological SurveyXi’an 710054China

The occurrence of landslides in Heifangtai plateau is primarily caused by the rise in water levels due to irrigation. To accurately understand the distribution of groundwater and its impact on the landslide hazard, a combination of Electrical Resistivity Tomography(ERT), Induced Polarization(IP) and Surface Nuclear Magnetic Resonance(SNMR) methods were used in this study. By conducting a comprehensive analysis, the characteristics of water-bearing structure in vertical and groundwater distribution in horizontal were detected;and the influence of the groundwater on plateau and landslides was also identified. The results indicate that the groundwater occurs in the loess aquifer with a three-layer structure in ***, the aquifer has a unified water table over the plateau, with a low water level in the north and high one in the south. The high resistivity bedrock uplift belt in the middle of the plateau forms a watershed,with the north side of the uplift belt being a relatively stable slope area with stable water content and fewer geological disasters. In contrast, the south side of the uplift belt is a disaster-prone region with vertical fissures well developed in the loess aquifers. The southern landslides are characterized by the interphase distribution of high and low electrical resistivity. The infiltration and discharge of groundwater result in the formation of a collapse belt in the low resistivity water-bearing structure of landslide, which causes the entire block with high resistivity and stable bedrock to slide. There was a newly formed landslide in a larger range at the landslide' s trailing edge. This study provides a scientific basis for the study of landslides mechanisms and disaster prevention by identifying the distribution characteristics of groundwater and analyzing its influence from a geophysical perspective in Heifangtai.

关键词： ERT IP SNMR distribution characteristics Uplift belt Sliding surface

The Changing characteristics of Profile distribution of Organic Nitrogen Components in Apple-pear Orchard Soil

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Agricultural Biotechnology 2021年第4期10卷 130-133页

作者： Huan LIU Qian GAO Shiyuan LIU Jie LI Yu WANG Jicheng HAN Yong GUO Changli Institute of Pomology Hebei Academy of Agriculture and Forestry SciencesChangli 066600China

In order to evaluate the effects of soil depth on the contents of soil organic nitrogen,organic nitrogen forms in apple-pear orchard soil profile were quantified using the method proposed by Bremner in *** results indicated that in addition to the amino sugar-N,all the soil organic N components within the same soil layer in wasteland were more than those in apple-pear orchard soil;with the layer depth increasing,the contents of different organic nitrogen forms in apple-pear orchard soil and wasteland were decreased;and the proportion of each organic N component within total hydrolysable N was different,and the percentages of ammonia N and amino acid-N components within total hydrolysable N were higher,especially the percentage of ammonia N components within total hydrolysable N was the highest.

关键词： Organic nitrogen components Profile Apple-pear orchard soil distribution characteristics

Pollution characteristics of 15 gas- and particle-phase phthalates in indoor and outdoor air in Hangzhou

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Journal of Environmental Sciences 2019年第12期31卷 107-119页

作者： Xingzi Ouyang Meng Xia Xueyou Shen Yu Zhan College of Environmental&Resource Sciences Zhejiang UniversityHangzhouZhejiang 310058China Zhejiang Provincial Key Laboratory of Organic Pollution Process and Control HangzhouZhejiang 310058China Department of Environmental Science and Engineering Sichuan UniversityChengduSichuan 610065China

Phthalate esters(PAEs),typical pollutants widely used as plasticizers,are ubiquitous in various indoor and outdoor *** exist in both gas and particle phases,posing risks to human *** the present study,we chose four typical kinds of indoor and outdoor environments with the longest average human residence times to assess the human exposure in Hangzhou,including newly decorated residences,ordinary residences,offices and outdoor *** order to analyze the pollution levels and characteristics of 15 gasand particle-phase PAEs in indoor and outdoor environments,air and particulate samples were collected *** total PAEs concentrations in the four types of environments were 25,396,25,466.8,15,388.8 and 3616.2 ng/m^3,*** and DEP were the most abundant,and DMPP was at the lowest *** variations in the distributions of indoor/outdoor,gas/particle-phase and different molecular weights of PAEs were observed,showing that indoor environments were the main sources of PAEs *** most PAEs tended to exsit in indoor sites and gas-phase,the high-molecular-weight chemicals tended to exist in the particle-phase and were mainly found in *** were more likely adsorbed by small particles,especially for the indoor *** existed a good correlation between the particle matter concentrations and the PAEs *** addition,neither temperature nor humidity had obvious effects on the distributions of the PAEs concentrations.

关键词： Phthalate esters Indoor and outdoor air Gas and particle phase distribution characteristics Particles