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distribution of oxide inclusions in H13 castings under super-gravity field with multi-stage rotation speeds

Journal of Iron and Steel Research(International) 2024年第1期31卷 121-133页

作者： Shao-ying Li Xiao-jun Xi Xing-ming Zhao Han-jie Guo Jing Guo School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing100083China Beijing Beiye Functional Materials Corporation Beijing100192China Shandong Tianwu Forming Technology Co. Ltd.Liaocheng252024ShandongChina

The 42 kg industrial H13 castings were prepared by different super-gravity fields with multi-rotation speeds,and the distribution of oxide inclusions in the castings was studied.In addition,the inward movement Reynolds number and inward movement time of oxide inclusions as well as the solidification time of molten steel at different positions in the castings were calculated to clarify the removal mechanism of oxide inclusions in super-gravity field.The results show that the large size(i.e.,greater than 10μm)oxide inclusions are mainly concentrated in the inner and outer parts of the super-gravity castings with constant rotation speed(500 r min^(-1))and five-stage rotation speeds(500,600,750,850,and 950 r min^(-1)),respectively,while there are no large oxide inclusions in the super-gravity castings with three-stage rotation speeds(500,600,and 750 r min^(-1)).Although an increase in the particle size of inclusion and the rotation speed in super-gravity field is conducive to the increase in the inward movement Reynolds number of oxide inclusions and reduction in the inward movement time of oxide inclusions,it will reduce the local solidification time of molten steel.In the range of the rotation speed studied,the super-gravity field with three-stage rotation speeds has the best effect on the removal of inclusions in H13 molten steel.

关键词： distribution Oxide inclusion H13 casting Super-gravity field Rotation speed

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distribution,risk evaluation,and source analysis of the heavy metals in the sediment deposition of the lower Shichuanhe River,Shaanxi,China

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地球化学学报(英文) 2023年第5期42卷 832-844页

作者： Chenhui Hou Caixia Feng Shen Liu Department of Geology Northwest UniversityXi’an 710069China

In this study, 30 sediment samples were collected from the lower reaches of the Shichuanhe River in Xi’an, Shaanxi Province, China, to test the distribution of heavy metal elements in this area and for an analysis of the pollution levels of this area, hope to provide guidance on agricultural production activities in this region. The results show that the heavy metal elements in this area are mainly concentrated at the Qinghe River and Shichuanhe River confluences. Furthermore, the element contents are higher than that of the background levels of the continental crust(UCC) and close to the background levels of the soil from Shaanxi Province;the two most enriched elements are Cd and As, with contents of 0.79 and 22.7 mg·kg-1, respectively, and their contents are 3.8 and 1.72 times higher than that of the background values. Herein, the heavy metal pollution assessment methods applied indicated that Cd and As are the two most abundant pollutant elements in the area’s soils. As has a peak geo-accumulation index value of 3, and the pollution level is high, while Cd exhibits high potential ecological risks due to its high toxicity(potential risk index of 143) and an active fraction of more than 64%.In addition, a principal component analysis and hierarchical cluster analysis study showed that there are two sources of the heavy metals in this area. The Zn, As, Ni, Cu, Pb,and Cr are mainly from natural sources, and the Cd likely comes from a discharge of untreated agricultural wastewater in the region. The Cd which poses a high potential risk and mainly results from human activities, needs to be further monitored.

关键词： distribution Risk evaluation Source analysis Heavy metals Sediment Ecological risk

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distribution of phytoplankton in the East China Sea and the southern Yellow Sea in spring in relation to environmental variables and dimethylsulfide compounds

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Acta Oceanologica Sinica 2022年第6期41卷 41-53页

作者： Jiawei Zhang Yanghang Chen Xueyan Ren Vishal Patil Lin Sun Xuesong Li Junrong Liang Jun Zhang Yahui Gao Changping Chen School of Life Sciences Xiamen UniversityXiamen 361102China Key Laboratory of the Coastal and Wetland Ecosystems of Ministry of Education Xiamen UniversityXiamen 361102China State Key Laboratory of Marine Environmental Science Xiamen UniversityXiamen 361102China Laboratory of Marine Biology and Ecology Third Institute of OceanographyState Oceanic AdministrationXiamen 361005China Eco-Environmental Monitoring and Research Center Pearl River Valley and South China Sea Ecology and Environment AdministrationMinistry of Ecology and EnvironmentGuangzhou 510610China

The coastal ecosystems are highly sensitive to climate change and are usually influenced by variations in phytoplankton communities and water physiochemical factors.In the present study,the phytoplankton community,chlorophyll a(Chl a)and their relationships with environmental variables and dimethylsulfide(DMS)and dimethylsulfoniopropionate(DMSP)were investigated in spring 2017(March 24 to April 16)in the East China Sea(26.0°-33.0°N,120.0°-128.0°E)and southern Yellow Sea(31.0°-36.0°N,120.0°-125.0°E).The spatial distributions of phytoplankton species composition and cell density were investigated by qualitative and quantitative methods and were compared with historical data to study phytoplankton species succession in the survey area.The results showed that there were 275 phytoplankton species belonging to 90 genera and 6 phyla in the survey area,of which 208 species belonged to 62 genera of Bacillariophyta and 56 species belonged to 20 genera of Pyrrophyta.The dominant phytoplankton species were Skeletonema dohrnii,Chaetoceros vanheurckii and Prorocentrum donghaiense.The phytoplankton cell densities ranged from 0.06×10^(4)cells/L to 418.73×10^(4)cells/L,with an average value of 21.46×10^(4)cells/L.In spring,the average ratio of Bacillariophyta/Pyrrophyta was41.13 for the entire study area.The areas with high phytoplankton cell density were mainly distributed in the northern South Yellow Sea and offshore waters of the East China Sea.According to a canonical correspondence analysis among phytoplankton and environmental parameters,the water Chl a concentrations were notably consistent with phytoplankton cell density(P<0.001),and both showed significant negative correlations with salinity and nitrite(P<0.05)and significant positive correlations with dissolved oxygen and pH(P<0.001).There was a significant positive correlation between diatom(both in cell density and in dominant species)and DMS(P<0.05),which indicated that diatoms play a greater role in DMS production in this investigated area.

关键词： phytoplankton distribution East China Sea southern Yellow Sea dimethylsulfoniopropionate

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distribution and sources of polycyclic aromatic hydrocarbons in the water column of Kongsfjorden, Arctic

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Journal of Environmental Sciences 2020年第11期32卷 186-193页

作者： Ruijing Li Hui Gao Zhongqiang Ji Shuaichen Jin Linke Ge Humin Zong Liping Jiao Zhifeng Zhang Guangshui Na National Marine Environmental Monitoring Center Dalian 116023China Key Laboratory of Marine Ecosystems and Biogeochemistry Second Institute of OceanographyMinistry of Nature ResourcesHangzhou 310012China Key Laboratory of Ocean-Atmospheric Chemistry and Global Change Third Institute of OceanographyMinistry of Nature ResourcesXiamen 361005China Hainan Tropical Ocean University Key Laboratory of Utilization and Conservation for Tropical Marine BioresourcesMinistry of EducationChina

Kongsfjorden is known for its characteristic multi-layer water mass formed by the convergence of freshwaters from nearby glaciers and rivers and saline water from the Atlantic and Arctic.The distribution of polycyclic aromatic hydrocarbons(PAHs)in the water column of Kongsfjorden was investigated and their potential sources were analyzed.The total concentrations of 16 PAHs in the surface seawater and river water were in the range of 33.4-79.8 ng/L(mean 48.5 ng/L)and 2.3-201.4 ng/L(mean 126.1 ng/L),respectively.Horizontally,PAHs were mainly concentrated around river estuaries and the glacier front in the dissolved phase.Vertically,the PAHs in the particulate phase followed surface-enrichment and depth-depletion patterns in most stations,with the maximum concentration found at 50 m depth in the central area of Kongsfjorden.The compositions of PAHs in seawater and rivers were similar,with two-ring and tricyclic PAHs comprising the majority of the dissolved and particulate phases.PAHs found in Kongsfjorden waters appeared to be derived from multiple sources such as petroleum and coal combustion.PAHs in the bay mouth of Kongsfjorden were mainly introduced by the West Spitsbergen Current and the Arctic waters,while in the inner bay,atmospheric deposition and local sources were the major contributors.The distribution of PAHs was mainly attributed to the suspended particulate distribution.

关键词： PAHs distribution Source Water mass Kongsfjorden

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distribution of Suitable Environments for Phlebotomus chinensis as the Vector for Mountain-Type Zoonotic Visceral Leishmaniasis-Six Provinces, China

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China CDC weekly 2020年第42期2卷 815-819页

作者： Xinyi Wang Jingbo Xue Shang Xia Shuai Han Xiaokang Hu Zhengbin Zhou Yi Zhang Shizhu Li National Institute of Parasitic Diseases Chinese Center for Disease Control and PreventionChinese Center for Tropical Diseases ResearchKey Laboratory of Parasite and Vector BiologyMinistry of HealthWHO Collaborating Center for Tropical DiseasesNational Center for International Research on Tropical DiseasesMinistry of Science and TechnologyShanghaiChina School of Global Health Chinese Center for Tropical Diseases ResearchShanghai Jiao Tong University School of MedicineShanghaiChina

Summary What is already known on this topic?Phlebotomus chinensis(P.chinensis)is a sandfly and the main vector of mountain-type zoonotic visceral leishmaniasis(MT-ZVL)in China.However,the distribution of suitable envi... 详细信息

关键词： China distribution chinensis

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distribution of the COVID-19 epidemic and correlation with population emigration from Wuhan,China

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Chinese Medical Journal 2020年第9期133卷 1044-1050页

作者： Ze-Liang Chen Qi Zhang Yi Lu Zhong-Min Guo Xi Zhang Wen-Jun Zhang Cheng Guo Cong-Hui Liao Qian-Lin Li Xiao-Hu Han Jia-Hai Lu One Health Center School of Public HealthSun Yat-sen UniversityGuangzhouGuangdong 510080China Key Laboratory of Livestock Infectious Diseases in Northeast China Ministry of EducationShenyang Agricultural UniversityShenyangLiaoning 110866China College of Animal Science and Veterinary Medicine Shenyang Agricultural UniversityShenyangLiaoning 110866China Department of Health Law Policy and ManagementSchool of Public HealthBoston UniversityBostonMA 02215USA Animal Experiment Center Sun Yat-sen UniversityGuangzhouGuangdong 510080China Department of Biological Science and Technology School of Life SciencesSun Yat-sen UniversityGuangzhouGuangdong 510080China Center for Infection and Immunity Mailman School of Public HealthColumbia UniversityNew YorkNY 10032USA

Background:The ongoing new coronavirus pneumonia(Corona Virus Disease 2019,COVID-19)outbreak is spreading in China,but it has not yet reached its peak.Five million people emigrated from Wuhan before lockdown,potentially representing a source of virus infection.Determining case distribution and its correlation with population emigration from Wuhan in the early stage of the epidemic is of great importance for early warning and for the prevention of future outbreaks.Methods:The official case report on the COVID-19 epidemic was collected as of January 30,2020.Time and location information on COVID-19 cases was extracted and analyzed using ArcGIS and WinBUGS software.Data on population migration from Wuhan city and Hubei province were extracted from Baidu Qianxi,and their correlation with the number of cases was analyzed.Results:The COVID-19 confirmed and death cases in Hubei province accounted for 59.91%(5806/9692)and 95.77%(204/213)of the total cases in China,respectively.Hot spot provinces included Sichuan and Yunnan,which are adjacent to Hubei.The time risk of Hubei province on the following day was 1.960 times that on the previous day.The number of cases in some cities was relatively low,but the time risk appeared to be continuously rising.The correlation coefficient between the provincial number of cases and emigration from Wuhan was up to 0.943.The lockdown of 17 cities in Hubei province and the implementation of nationwide control measures efficiently prevented an exponential growth in the number of cases.Conclusions:The population that emigrated from Wuhan was the main infection source in other cities and provinces.Some cities with a low number of cases showed a rapid increase in case load.Owing to the upcoming Spring Festival return wave,understanding the risk trends in different regions is crucial to ensure preparedness at both the individual and organization levels and to prevent new outbreaks.

关键词： Corona Virus Disease 2019 Temporal Spatial distribution Outbreak

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distribution of High-sensitivity C-reactive Protein Status in an Urban Population in China

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Biomedical and Environmental Sciences 2020年第6期33卷 396-402页

作者： TANG Yan Bin HUO Jun Sheng HUANG Jian LI Hong PIAO Jian Hua SUN Jing WANG Li Juan Key Laboratory of Trace Element Nutrition MOH National Institute for Nutrition and HealthChinese Center for Disease Control and PreventionBeijing 100050China Beijing Center for Disease Control and Prevention Beijing 100013China

Objectives To evaluate the distribution by age and sex of serum high-sensitivity C-reactive protein(hsCRP)in an urban Chinese population and to provide a profile prediction for the risk of bacterial infection,inflammatory diseases,or tissue damages in the body.Methods Serum hsCRP was determined using the Roche Tina-quant immuno-turbidimetric assay on a Hitachi 7600–010 automatic biochemical analyzer(Roche Diagnostics)in 1,572 males and 1,800 females,including 78 pregnant women,who were derived from the National Health and Nutrition Survey in2010–2012.Results The average hsCRP concentration in urban China was 0.68 mg/L for males and 0.65 mg/L for females.Significant differences in hsCRP were found among different age groups(Pdistribution of the hsCRP status of residents in large cities in China was influenced by age and gender,and the hsCRP levels of both sexes increased gradually with age.In addition,hsCRP concentration was higher in healthy pregnant women than in non-pregnant women.Basing on our results,we recommend that this parameter be included in future national and international screening for early detection of various illnesses.

关键词： High-sensitivity C-reactive protein Urban population Inflammation distribution

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distribution of polychlorinated naphthalenes(PCNs) in the whole blood of typical meat animals

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Journal of Environmental Sciences 2018年第10期30卷 208-212页

作者： Ying Han Wenbin Liu Haifeng Li Rongrong Lei Guorui Liu Lirong Gao Guijin Su State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesBeijing100085China University of Chinese Academy of Sciences Beijing 100049 China

The concentrations and distribution of polychlorinated naphthalenes（PCNs） in the whole blood of eight typical terrestrial meat animals（chicken, duck, rabbit, pig, cattle, sheep,horse and donkey） consumed daily in our life were investigated. The total concentrations（on a liquid volume basis） of PCNs were in a range from 305 to 987 pg/L. Donkey blood contained the highest PCN concentrations. Mono-CNs were the dominant homolog group,accounting for 38%–71% PCNs. Apart from the mono-CNs and tri-CNs homolog groups, two hepta-CNs（mean： 9.5%） contributed most, followed by tetra-CNs（mean： 6.5%）. The congeners CN1, 5/7, 24/14, 27/30, 52/60, 66/67, and 73 were the most abundant congeners or congener groups. The highest toxicity equivalencies（TEQs） were observed in cattle blood（117.4 fg TEQ/L） then chicken blood（117.1 fg TEQ/L）. CN73 contributed 65% to total TEQs,followed by CN70（20%） and CN66/67（14%）. The dietary intakes of PCNs were also estimated.Chicken meat, which forms the second largest component of meat product consumption in China, contributed most to the total TEQs（61%）, followed by beef（27%） and pork（5.9%）. The consumption of chicken might pose the highest risk from exposure to PCNs than other types of meat to populations who prefer to eat chicken meat.

关键词： PCNs Whole blood Animal distribution Dietary intake

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Accumulation, transportation, and distribution of tetracycline and cadmium in rice

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Journal of Environmental Sciences 2023年第4期126卷 58-69页

作者： Chunfeng He Jini Zhou Chen Yang Zhiyi Song Junheng He Ziqing Huang Yurong Deng Jinling Wang Yu Xiong Zhi Dang College of Environment and Energy South China University of TechnologyGuangzhou 510006China The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters Ministry of EducationGuangzhou 510006China Department of Environmental Sciences The State University of New JerseyRutgers UniversityNew BrunswickNJ 08901USA Guangdong Institute of Ecological Environment and Soil Guangzhou 510650China

Co-exposure to heavy metal and antibiotic pollution might result in complexation and synergistic interactions,affecting rice growth and further exacerbating pollutant enrichment.Therefore,our study sought to clarify the influence of different Tetracycline (TC) and Cadmium(Cd) concentration ratios (both alone and combined) on rice growth,pollutant accumulation,and transportation during the tillering stage in hydroponic system.Surprisingly,our findings indicated that the interaction between TC and Cd could alleviate the toxic effects of TC/Cd on aerial rice structures and decrease pollutant burdens during root elongation.In contrast,TC and Cd synergistically promoted the accumulation of TC/Cd in rice roots.However,their interaction increased the accumulation of TC in roots while decreasing the accumulation of Cd when the toxicant doses increased.The strong affinity of rice to Cd promoted its upward transport from the roots,whereas the toxic effects of TC reduced TC transport.Therefore,the combined toxicity of the two pollutants inhibited their upward transport.Additionally,a low concentration of TC promoted the accumulation of Cd in rice mainly in the root tip.Furthermore,a certain dose of TC promoted the upward migration of Cd from the root tip.Laser ablation-inductively coupled plasma mass spectrometry demonstrated that Cd mainly accumulated in the epidermis and stele of the root,whereas Fe mainly accumulated in the epidermis,which inhibited the absorption and accumulation of Cd by the rice roots through the generation of a Fe plaque.Our findings thus provide insights into the effects of TC and Cd co-exposure on rice growth.

关键词： Laser ablation-inductively coupled plasma mass spectrometry Tetracycline Cadmium Accumulation distribution

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Perfluoroalkyl acids(PFAAs) in urban surface water of Shijiazhuang, China: Occurrence, distribution,sources and ecological risks

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Journal of Environmental Sciences 2023年第3期125卷 185-193页

作者： Xiaotong Li Yuan Wang Chengjing Qian Zhixin Zheng Yali Shi Jiansheng Cui Yaqi Cai College of Environmental Science and Engineering Hebei University of Science and TechnologyShijiazhuang 050018China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental ScienceUniversity of Chinese Academy of SciencesBeijing 100085China Nutrition&Health Research Institute COFCO CorporationBeijing 102209China School of Environment Hangzhou Institute for Advanced StudyUCASHangzhou 310024China

It is extremely important to analyze the contaminative behaviors of Perfluoroalkyl acids(PFAAs) due to their serious threats to urban environments which are closely related to humans. Current study aimed to explore the distribution, source apportionment and ecological risk assessment of PFAAs in surface water from Shijiazhuang, China. The concentrations of ΣPFAAs ranged from 19.5 to 125.9 ng/L in the investigation area. Perfluorobutanesulfonic acid(PFBS) and perfluoropentanoic acid(PFPeA) were the predominant contaminants(mean value: 14.3 ng/L and 16.6 ng/L, respectively). The distribution of PFAAs according to geospatial analysis and hierarchical clustering analysis(HCA) showed that higher levels of ΣPFAAs were detected in the southern surface water of Shijiazhuang and there was a stepwise decrease from the wet season to the dry season. Furthermore, based on source apportionment,the dominant potential sources were found to be wastewater treatment plant(WWTP) effluents and industrial discharge. The risk quotients(RQs) revealed low ecological risks of all PFAAs for aquatic organisms in Shijiazhuang surface water. Collectively, this study provided basic data for regulatory strategies for controlling PFAA pollutions in urban surface water.

关键词： Perfluoroalkyl acids distribution Source apportionment Risk assessment Urban surface water

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