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occurrence and vertical distribution of aluminum and rare earths in weathered crust elution-deposited rare earth ore:Effect of soil solution pH and clay minerals

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Journal of Rare Earths 2024年第7期42卷 1394-1402页

作者： Jiaxin Pan Longsheng Zhao Zheng Li Xiaowei Huang Zongyu Feng Jun Chen National Engineering Research Center for Rare Earth China GRINM Group Co.Ltd. School of Metallurgical and Ecological Engineering University of Science and Technology Beijing (USTB) GRIREM Advanced Materials Co. Ltd. GRIREM Hi-Tech Co. Ltd. GRIMAT Engineering Institute Co. Ltd.

Weathered crust elution-deposited rare earth ore is crucial source of medium and heavy rare earths,with in-situ leaching being the most common mining method.The high contents of impurity of aluminum in the leach solution are a significant challenge for the subsequent enrichment process of rare earths.A comprehensive understanding of the occurrences and vertical distribution of aluminum and rare earths within typical vertical profiles can provide valuable insights into entire design of the in-situ leaching.This paper improves a five-step sequential extraction method to analyze the occurrence and vertical distribution of rare earths and aluminum in vertical profiles from Chongzuo and Longyan.Experimental results demonstrate that soil solution pH is the main factor affecting the vertical distribution of ionexchangeable rare earths.Both samples have distinct areas of enrichment for ion-exchangeable rare earths or aluminum.Ion-exchangeable rare earths are primary concentrated in the middle and lower parts of the ore layer(4-13 m in Chongzuo,14-22 m in Longyan),while the ion-exchangeable aluminum is mainly enriched in the upper part of the ore layer(1-5 m in Chongzuo,and 2-14 m in Longyan).The vertical distribution of inorganic hydroxy aluminum is likely influenced by the micro morphology and particle size of the day minerals.The inorganic hydroxy aluminum concentration in Chongzuo samples decreases continuously from 415.65 to 120.95 mg/kg with increasing sampling depth,whereas the concentration in Longyan samples(110.55-171.27 mg/kg) is almost independence with sampling depth.These results provide direct guidance for the entire design of the injection well depth and the leaching parameters,thereby inhibiting the leaching of impurity of aluminum and lower the consumption of leaching agent.

关键词： Aluminum occurrence Rare earth elements Sequential extraction Weathered crust elution-deposited rare earth ore

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An updated inventory of marine opisthobranch(Mollusca,Gastropoda)from the territorial waters of the Republic of Mauritius

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Journal of Oceanology and Limnology 2024年第1期42卷 226-243页

作者： Lisa AH SHEE TEE Chandani APPADOO Daneshwar PUCHOOA Vishwakalyan BHOYROO Department of Agricultural&Food Science Faculty of AgricultureUniversity of MauritiusRéduit 80837Mauritius Department of Biosciences&Ocean Studies Pole of Research Excellence Sustainable Marine BiodiversityFaculty of ScienceUniversity of MauritiusRéduit 80837Mauritius

Island ecosystems support diverse aquatic invertebrate communities comprising endemic taxa.Documentation of existing species is important for conservation.In this study,a checklist of marine opisthobranch from the Republic of Mauritius is presented.A combination of benthic surveys(50 m×5 m in triplicates),rover diving techniques and photo documentation were used over two years(2018–2020)within 35 sheltered and unsheltered lagoons.Morphological and molecular analysis were used for identification.Species composition within sheltered and unsheltered areas in Mauritius was estimated using the Bray-Curtis similarity.The checklist featured 117 species belonging to 61 genera and 28families,of which 13 are new records.The findings increased the knowledge of opisthobranch diversity from the Mauritius by 15.4%.Among the listed species,the distribution range of Cyerce nigra,Actinocyclus papillatus,and Phyllidia picta extended from the Western Pacific to the South Western Indian Ocean.Molecular analysis of the undescribed Gymnodoris sp.showed it resembled Gymnodoris sp.from Hawaii and were different by a genetic distance value of 10.6%.The species richness and evenness were higher within the sheltered regions of Mauritius which harboured the food resource of opisthobranch.These areas as compared to unsheltered regions were heavily populated,suggesting the probable influence of wave actions on opisthobranch diversity and abundance.The order Nudibranchia was reported as most speciose,with 86 species.The Sacoglossa and Nudibranchia were observed only on macroalgae and sponges respectively.High abundance was also recorded on shipwrecks which are the most common form of artificial reefs.With the inclusion of observations from previous studies,201species belonging to 94 genera and 36 families are now known from the Mauritius.

关键词： marine opisthobranch inventory new record occurrence Republic of Mauritius Indian Ocean

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occurrence, partition behavior, source and ecological risk assessment of nitro-PAHs in the sediment and water of Taige Canal, China

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Journal of Environmental Sciences 2023年第2期124卷 782-793页

作者： Jijie Kong Tao Ma Xiaoyu Cao Weidi Li Fengxiao Zhu Huan He Cheng Sun Shaogui Yang Shiyin Li Qiming Xian School of Environment Nanjing Normal UniversityNanjing 210023China School of Geography Nanjing Normal UniversityNanjing 210023China The State Key Laboratory of Pollution Control and Resource Reuse School of the EnvironmentNanjing UniversityNanjing 210023China Fujian Provincial Key laboratory of Eco-Industrial Green Technology College of Ecological and Resource EngineeringWuyi UniversityWuyishan 354300China Nanjing Institute of Environmental Sciences Ministry of Ecology and EnvironmentNanjing 210042China

Nitrated polycyclic aromatic hydrocarbons(NPAHs)are widespread organic pollutants that possess carcinogenic and mutagenic properties,so they may pose a risk to the environment and human health.In this study,the concentrations of 15 NPAHs and 16 polycyclic aromatic hydrocarbons(PAHs)in 30 surface water samples and 26 sediment samples were measured in 2018 from the Taige Canal,one of the main rivers flowing into Taihu Lake,China.The total NPAH concentrations in water and sediment ranged from 14.7 to 235 ng/L and 22.9 to 96.5 ng/g dw,respectively.9-nitrophenanthrene(nd–76.3 ng/L)was the dominant compound in surface water,while 2+3-nitrofluoranthene(1.73–18.1 ng/g dw)dominated in sediment.Among PAHs,concentration ranging from 1,097 to 2,981 ng/L and 1,089 to 4,489 ng/g dw in surface water and sediment,respectively.There was a strong positive correlation between the log octanol-water partition coefficient(Kow)and log sediment-water partition coefficient due to hydrophobic interaction.The fugacity fraction value increased with the decrease of log Kow,and chrysene was transferred from water into sediment.The residual NPAHs in surface water and sediment of the Taige Canal have partial correlation.Diesel engine and coal combustion emissions were probably the principal sources of NPAHs in surface water and sediment.The results of ecological risk assessment showed that some NPAHs inwater(e.g,1-nitropyrene and 6-nitrochrysene)and sediment(e.g.,2-nitrobiphenyl,5-nitroacenaphthene,9-nitrophenanthrene and 2+3-nitrofluoranthene)had moderate ecological risks,which should be of concern.

关键词： Nitrated polycyclic aromatic hydrocarbons(NPAHs) occurrence Partition behavior Source apportionment Ecological risk assessment

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occurrence and distribution of geminiviruses in China

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Science China(Life Sciences) 2022年第8期65卷 1498-1503页

作者： Fangfang Li Rui Qiao Zhanqi Wang Xiuling Yang Xueping Zhou State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193China Key Laboratory of Vector Biology and Pathogen Control of Zhejiang Province College of Life SciencesHuzhou UniversityHuzhou 313000China State Key Laboratory of Rice Biology Institute of BiotechnologyZhejiang UniversityHangzhou 310058China

Geminiviruses are a group of plant viruses that cause severe diseases in many economically important crops worldwide, leading to devastating losses to agricultural production. Here we summarize the occurrence and distribution of geminiviruses in China,which provides valuable information for further epidemiological studies and supports the development of effective disease management strategies.

关键词： geminiviruses occurrence distribution China

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occurrence of asymptomatic malaria infection and living conditions in the lowlands of Ethiopia: a community-based cross-sectional study

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Infectious Diseases of Poverty 2022年第5期11卷 41-49页

作者： Endale Mengesha Goshu Meseret Dessalegne Zerefa Habteyes Hailu Tola Water and Public Health Stream Ethiopian Institute of Water ResourcesAddis Ababa UniversityAddis AbabaEthiopia Tuberculosis/HIV Research Directorate Ethiopian Public Health InstituteP.O.Box 1242Addis AbabaEthiopia.

Background:A significant decline in malaria burden was documented in previously high burden African countries.Even though the global decline in malaria burden is significant,about 95%of it was typically found in 29 African countries and the decline was affected by COVID-19 in 2020.The considerable reduction in malaria incidence was noted due to effective prevention and treatment efforts,and rapid changes in living conditions.The relationship between the occurrence of asymptomatic malaria infection and household living conditions is well unstudied.This study aimed to determine the association between household living conditions and the occurrence of asymptomatic malaria in the lowlands of Ethiopia.Methods:A community-based cross-sectional study was conducted from January to March 2021 in twelve villages of Gambella,Southern Nation Nationalities and People Region and Afar in Ethiopia.A total of 1366 households were randomly selected,interviewed,and tested for malaria by rapid diagnostic test and blood film microscopic examination.Multiple logistic regression model was used to determine the independent association between living conditions and asymptomatic malaria infection.Results:The prevalence of asymptomatic malaria infection among individuals living in dwellings built with traditional floor/wall/roof ranges from 8.1%to 8.4%while it ranges from 2.0%to 4.6%among those living in modern floor/wall/roof houses.Dwellings built with traditional wall materials(P=0.050),spending nights with cattle in the same house(P<0.001),and availability of kitchen in the main house with no partition(P=0.004)were significantly associated with asymptomatic malaria infection.Conclusions:Asymptomatic malaria infection was 4.3 times higher among occupants residing in dwellings built with traditional wall materials;5.6 times higher among households spending nights with cattle in the same house,and 2.3 times higher among households with kitchen in the main house with no partition.Therefore,policies and strategies on malaria elimination nee

关键词： occurrence Asymptomatic Malaria Households Wall Prevalence Mosquito And livestock

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occurrence and Health Risk of Perfluoroalkyl Acids in Popular Shellfish from a Typical Coastal Area of the East China

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Chemical Research in Chinese Universities 2023年第3期39卷 492-501页

作者： LIU Ruolin LIU Mei ZHAO Chuxuan FU Jianjie ZHOU Wei ZHANG Qinghua Martin HANSEN DONG Yin Sino-Danish College University of Chinese Academy of SciencesBeijing100049P.R.China State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085P.R.China School of Environment and Health Jianghan UniversityWuhan430056P.R.China Environmental Metabolomics Lab Department of Environmental ScienceAarhus UniversityFrederiksborgvej 3994000RoskildeDenmark The People’s Hospital of Yuhuan Yuhuan317600P.R.China

As crucial homologous members of per-and polyfluoroalkyl substances(PFASs),perfluoroalkyl acids(PFAAs)have aroused wide public concern because of their unique properties(persistence,bioaccumulation,long-distance migration and toxicity).Studies have shown their potential hazard to wildlife and humans,with food consumption as one of the primary routes of PFAA exposure for general population,especially seafood intake.In this study,17 PFAAs were quantified in 9 shellfish species from Yuhuan City,a typical coastal area of the East China.The total mean concentrations of PFAAs were in the range of 5.03–381 ng/g dry weight(dw),with the highest concentration found in Neverita didyma and the lowest in Babylonia lutosa.Concentrations and composition profiles of PFAAs varied significantly among different species,indicating differences in the bioaccumulation potential of PFAAs among species.Perfluorooctanoic acid(PFOA)was presented as the most abundant PFAA in this study,followed by perfluorobutanoic acid(PFBA).Significant positive correlations were observed among some individual PFAAs(p<0.05),indicating that they may share similar pollution sources or undergo similar compound behaviors.Health risk assessment indicated a relatively high threat for local residents exposed to PFAAs through shellfish consumption.

关键词： Perfluoroalkyl acid Shellfish East China Sea occurrence Health risk assessment

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Plastic occurrence,sources,and impacts in Antarctic environment and biota

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Water Biology and Security 2022年第2期1卷 60-71页

作者： Gabriella Caruso Elisa Bergami Neelu Singh Ilaria Corsi Institute of Polar Sciences National Research CouncilMessinaItaly British Antarctic Survey Natural Environment Research CouncilHigh CrossMadingley RoadCambridgeCB30ETUK Department of Life Sciences University of Modena and Reggio EmiliaModenaItaly Norwegian Polar Institute LongyearbyenNorway Department of Physical Earth and Environmental Sciences University of Siena53100SienaItaly

Several studies have documented that plastic pollution is affecting one of the most remote and pristine regions of our planet,Antarctica.Plastics of different size and polymeric composition have been retrieved in Antarctic sea ice,surface waters and sediments,with microplastics(mostly fibers)found both in terrestrial and marine organisms.Such evidence raises concerns about potential detrimental effects on biodiversity and ecosystem functions.The present review aims to report the most up-to-date knowledge on occurrence and distribution of plastic pollution in the Antarctic environment and biota including interaction with microorganisms,potential sources,and its impact on Antarctic biota.Our understanding of plastic pollution in this polar region will help us define the human footprint in Antarctica and predict future ecological risks.

关键词： Anthropogenic impact Contamination Microplastics Southern ocean Antarctica occurrence Sources Ecotoxicity Colonization Biosecurity

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occurrence and volatility of several trace elements in pulverized coal boiler

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Journal of Environmental Sciences 2004年第2期16卷 242-246页

作者： HUANGYa-ji JINBao-sheng ZHONGZhao-ping XIAORui TANGZhi-yong RENHui-feng EducationMinistryKeyLaboratoryonCleanCoalPowerGenerationandConll）ustionTechnology SoutheastUniversityNanjing210096China. ThermoelectricPowerPlantofYangziPetrochemicalCo. Nanjing210002China.

The contents of eight trace elements(Mn, Cr, Pb, As, Se, Zn, Cd, Hg) in raw coal, bottom ash and fly ash were measured in a 220 t/h pulverized coal boiler. Factors affecting distribution of trace elements were investigated, including fly ash diameter, furnace temperature, oxygen content and trace elements' characters. One coefficient of Meij was also improved to more directly show element enrichment in combustion products. These elements may be classified into three groups according to their distribution: Group 1: Hg, which is very volatile. Group 2: Pb, Zn, Cd, which are partially volatile. Group 3: Mn, which is hardly volatile. Se may be located between groups 1 and 2 Cr has properties of both group 1 and 3 In addition, the smaller diameter of fly ash, the more relative enrichment of trace elements(except Mn). The fly ash showed different adsorption mechanisms of trace elements and the volatilization of trace elements rises with furnace temperature. Relative enrichments of trace elements(except Mn and Cr) in fly ash are larger than that in bottom ash. Low oxygen content can not always improve the volatilization of trace elements. Pb is easier to form chloride than Cd during coal combustion. Trace elements should be classified in accordance with factors.

关键词： occurrence volatility relative enrichment trace element group of elements

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occurrence characteristics of mercury in high-mercury coal and distribution rule of mercury in products of an air dense medium fluidized bed

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International Journal of Mining Science and Technology 2018年第6期28卷 1015-1020页

作者： Guilin Zhang Shulei Song Weiqiao Yang Bo Zhang Jianqing Wang Key Laboratory of Coal Processing & Efficient Utilization Ministry of EducationChina University of Mining and Technology

Mercury emitted from direct combustion of high-mercury coal does great harm to the environment. To make good use of high-mercury coal, it is necessary to study the occurrence characteristics of mercury in coal and high-efficient methods of mercury removal. In this paper, high-mercury coal of Guizhou Province of China was taken as an object to study the nature of mercury in coal and the rule of mercury removal by dry preparation method. Mercury mainly distributes in the medium and high density fractions, and has a good affinity with silicon, aluminum, iron, titanium, potassium, calcium, zinc, sodium and magnesium. It exists in minerals formed by these elements and presents significant correlation with ash in coal. After the high-mercury coal is separated by air dense medium fluidized bed, mercury content of clean coal is reduced to 1/10 of raw coal, while mercury content of gangue is increased to 3 times that of raw coal. This indicates that mercury in raw coal is rejected greatly by ADMFB and enriched in highdensity fractions. The rates of ash removal and mercury removal decrease with the density and present a very high correlation.

关键词： occurrence of mercury Affinity Air dense medium fluidized bed Correlation of mercury and ash removal Distribution rule of mercury

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occurrence,spatial and seasonal variation,and environmental risk of pharmaceutically active compounds in the Pearl River basin,South China

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Frontiers of Environmental Science & Engineering 2023年第4期17卷 83-95页

作者： Haojun Lei Kaisheng Yao Bin Yang Lingtian Xie Guangguo Ying SCNU Environmental Research Institute Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety&MOE Key Laboratory of Theoretical Chemistry of EnvironmentSouth China Normal UniversityGuangzhou 510006China School of Environment South China Normal UniversityGuangzhou 510006China Aquatic Ecology and Water Quality Management Group Wageningen University6700 AA WageningenNetherlands

The occurrence,fate,and environmental risk of 40 pharmaceutically active compounds(PhACs)from surface waters and sediments were comprehensively investigated in the Beijiang River,Xijiang River,and Maozhou River of the Pearl River basin,South China.Salicylic acid and diclofenac(antiinflammatory drugs),gemfibrozil(a lipid regulator),carbamazepine(an antiepileptic drug),diazepam(a psychoactive drug),and 2-methyl-4-chloro-phenoxyacetic acid(MCPA,a pesticide)were the most ubiquitous compounds in the studied region.The average concentrations of detected PhACs in surface waters and sediments ranged from 0.17 to 19.1 ng/L and 0.10 to 10.4 ng/g,respectively.Meanwhile,PhACs concentration in surface waters and sediments varied greatly among and within the Beijiang River,Xijiang River,and Maozhou River.The largest annual flux of PhACs of the Xijiang River and Beijiang River was more than 11000 kg per annum,whereas only 25.7 kg/a in the Maozhou River.In addition,the estimated emissions of PhACs in the Beijiang River,Xijiang River,and Maozhou River ranged respectively from 0.28 to 4.22 kg/a,0.12 to 6.72 kg/a,and 6.66 to 91.0 kg/a,and the backestimated usage varied with a range from 12.0 to 293 kg/a,6.79 to 944 kg/a,368 to 17459 kg/a.Moreover,the emissions of PhACs showed a close relationship with the gross domestic product(GDP)of each city along the Pearl River.The environmental risk assessment suggested that diazepam and ibuprofen had a moderate risk in this region.

关键词： Pharmaceutically active compounds occurrence Spatiotemporal variations Pearl River Environmental risk assessment

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