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Paleoenvironmental Characteristics of Paleogene Lacustrine Source Rocks in the Western Bozhong Sag,Bohai Bay Basin,China:Evidence from Biomarkers,Major and Trace Elements
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作者 WANG Xiang LIU Guangdi +6 位作者 SONG Zezhang SUN Mingliang WANG Xiaolin WANG Feilong CHEN Rongtao GENG Mingyang LI Yishu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期220-240,共21页
The organic matter(OM)enrichment mechanisms and depositional environment characteristics of lacustrine source rocks in the western Bozhong Sag,Bohai Bay Basin in Northeast China remain controversial.To address these i... The organic matter(OM)enrichment mechanisms and depositional environment characteristics of lacustrine source rocks in the western Bozhong Sag,Bohai Bay Basin in Northeast China remain controversial.To address these issues,based on Rock-Eval pyrolysis,kerogen macerals,H/C and O/C ratios,GC-MS,major and trace elements,the Dongying Formation Member(Mbr)3(E_(3)d_(3)),the Shahejie Formation mbrs 1 and 2(E_(2)s_(1+2)),and the Shahejie Mbr 3(E_(2)s_(3))source rocks in the western Bozhong Sag were studied.The above methods were used to reveal their geochemical properties,OM origins and depositional environments,all of which indicate that E_(2)s_(1+2)and E_(2)s_(3)are excellent source rocks,and that E_(3)d_(3)is of the second good quality.E_(3)d_(3)source rocks were formed under a warm and humid climate,mainly belong to fluvial/delta facies,the E_(3)d_(3)sediments formed under weakly oxidizing and freshwater conditions.Comparatively,the depositional environments of E_(2)s_(1+2)source rocks were arid and cold climate,representing saline or freshwater lacustrine facies,and the sediments of E_(2)s_(1+2)belong to anoxic or suboxic settings with large evaporation and salinity.During the period of E_(2)s_(3),the climate became warm and humid,indicating the freshwater lacustrine facies,and E_(2)s_(3)was characterized by freshwater and abundant algae.Moreover,compared with other intervals,the OM origin of E_(3)d_(3)source rocks has noticeable terrestrial input.The OM origin of the E_(2)s_(1+2)and E_(2)s_(3)are mainly plankton and bacteria.Tectonic subsidence and climate change have affected the changes of the depositional environment in the western Bozhong Sag,thus controlling the distribution of the source rocks,the geochemical characteristics in the three intervals of lacustrine source rocks have distinct differences.Overall,these factors are effective to evaluate the paleoenvironmental characteristics of source rocks by biomarkers,major and trace elements.The established models may have positive implications for research of lacustrine source rocks in offshore areas with few drillings. 展开更多
关键词 petroleum geology source rocks depositional environments biomarkers major elements trace elements Bozhong Sag
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Analysis Method and Application of Multiple Antiquities Sources in the Shahejie Formation of the Paleogene in the Southern Bohai Sea
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作者 Jianmin Zhang Honglin Yue Xijie Wang 《Open Journal of Applied Sciences》 2024年第4期1070-1079,共10页
B Oilfield is the most representative mid to deep oil field in the Bohai Sea, with the main oil bearing intervals being the upper and middle Shahejie-3 sections of the Paleogene Shahejie Formation. Through the develop... B Oilfield is the most representative mid to deep oil field in the Bohai Sea, with the main oil bearing intervals being the upper and middle Shahejie-3 sections of the Paleogene Shahejie Formation. Through the development of ancient landforms, characterization of material source channels, analysis of missing heavy mineral sources, and seismic reflection characteristics of multiple material source missing, the material sources of the middle and upper Shahejie-3 sections are analyzed. During the sedimentation period of the II oil formation in the middle section of the Shasan Formation, the study area was mainly dominated by the Kendong Uplift source rocks;During the sedimentation period of the I oil formation in the middle section of the Shasan Formation, there were three material sources in the study area, namely the Kendong Uplift, the Laibei Low Uplift, and the Weibei Uplift. The Kendong Uplift was the main material source, followed by the Laibei Low Uplift;During the sedimentation period of the Upper Shasan Formation, the study area still had three sources of material supply simultaneously. At this time, the Laibei Low Uplift was the main source area, while the Kendong Uplift and Weibei Uplift had a relatively small supply capacity for the study area. In the analysis of archaeological sources, the distribution characteristics of the sedimentary system in the third section of the Shahejie Formation have been clarified, providing a research basis for the later development and adjustment of the oilfield. 展开更多
关键词 Paleogeomorphology Characterization of source Channels tracing of Heavy Minerals Seismic Reflection Characteristics Sedimentary Systems
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Geochemical Tracing of Ore-forming Material Sources of Carlin-type Gold Deposits in the Yunnan-Guizhou-Guangxi Triangle Area --A Case Study of the Application of the Combined Silicon Isotopes Geochemistry and Siliceous Cathodoluminescence Analysis 被引量:1
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作者 LIU Xianfan NI Shijun +2 位作者 LU Qiuxia JIN Jingfu ZHU Laimin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第1期30-39,共10页
Abstract This paper deals with characteristics of silicon isotope compositions and siliceous cathodoluminescence of host rocks, ores and hydrothermal silicified quartz of the Carlin-type ore deposits in the Yunnan-Gui... Abstract This paper deals with characteristics of silicon isotope compositions and siliceous cathodoluminescence of host rocks, ores and hydrothermal silicified quartz of the Carlin-type ore deposits in the Yunnan-Guizhou-Guangxi triangle area. The study shows that primary silicified quartz is nonluminescent but quartz in host rocks and secondary silicified quartz are luminescent by the action of cathode rays. Correspondingly, silicon isotope compositions of host rocks, ores and hydro6thermal quartz veins are clearly distinguished. In strata from the Middle Triassic to the “Dachang” host bed, δ30Si of the host rocks ranges from 0.0% ?0.3%, while that of primary ore-forming silicified fluids from ?0.1% to ?0.4%; in the Upper Permian and Lower Carboniferous strata and Indosinian diabase host beds, δ30Si of the host rocks is from ?0.1% to ?0.2% and that of the primary silicified quartz veins from 0.3 % ?0.5 %. This pattern demonstrates the following geochemical mineralization process, primary ore-forming siliceous fluids migrated upwards quickly along the main passages of deep-seated faults from mantle to crust and entered secondary faults where gold deposits were eventually formed as a result of permeation and replacement of the siliceous ore-forming fluids into different ore-bearing strata. This gives important evidence for the fact that ore-forming fluids of this type of gold deposits were mainly derived from upper mantle differentiation and shows good prospects for deep gold deposits and geochemical background for large and superlarge gold deposits. 展开更多
关键词 silicon isotope siliceous cathodoluminescence tracing of ore-forming material source Carlin-type gold deposit Yunnan-Guizhou-Guangxi triangle area
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Erratum to:Tracing environmental lead sources on the Ao mountain of China using lead isotopic composition and biomonitoring
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作者 XIANG Zhong-xiang BING Hai-jian +3 位作者 WU Yan-hong ZHOU Jun LI Rui HE Xiao-li 《Journal of Mountain Science》 SCIE CSCD 2022年第7期2137-2137,共1页
The Electronic Supplementary Material of the article entitled“Tracing environmental lead sources on the Ao mountain of China using lead isotopic composition and biomonitoring”at https://doi.org/10.1007/s11629-016-43... The Electronic Supplementary Material of the article entitled“Tracing environmental lead sources on the Ao mountain of China using lead isotopic composition and biomonitoring”at https://doi.org/10.1007/s11629-016-4327-2 are swapped with the Electronic Supplementary Material of the article entitled“Temporal changes in wetland plant communities with decades of cumulative water pollution in two plateau lakes in China's Yunnan Province”at https://doi.org/10.1007/s11629-016-4037-9. 展开更多
关键词 sourceS entitled tracing
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Pollution source identification methods and remediation technologies of groundwater: A review
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作者 Ya-ci Liu Yu-hong Fei +2 位作者 Ya-song Li Xi-lin Bao Peng-wei Zhang 《China Geology》 CAS CSCD 2024年第1期125-137,共13页
Groundwater is an important source of drinking water.Groundwater pollution severely endangers drinking water safety and sustainable social development.In the case of groundwater pollution,the top priority is to identi... Groundwater is an important source of drinking water.Groundwater pollution severely endangers drinking water safety and sustainable social development.In the case of groundwater pollution,the top priority is to identify pollution sources,and accurate information on pollution sources is the premise of efficient remediation.Then,an appropriate pollution remediation scheme should be developed according to information on pollution sources,site conditions,and economic costs.The methods for identifying pollution sources mainly include geophysical exploration,geochemistry,isotopic tracing,and numerical modeling.Among these identification methods,only the numerical modeling can recognize various information on pollution sources,while other methods can only identify a certain aspect of pollution sources.The remediation technologies of groundwater can be divided into in-situ and ex-situ remediation technologies according to the remediation location.The in-situ remediation technologies enjoy low costs and a wide remediation range,but their remediation performance is prone to be affected by environmental conditions and cause secondary pollution.The ex-situ remediation technologies boast high remediation efficiency,high processing capacity,and high treatment concentration but suffer high costs.Different methods for pollution source identification and remediation technologies are applicable to different conditions.To achieve the expected identification and remediation results,it is feasible to combine several methods and technologies according to the actual hydrogeological conditions of contaminated sites and the nature of pollutants.Additionally,detailed knowledge about the hydrogeological conditions and stratigraphic structure of the contaminated site is the basis of all work regardless of the adopted identification methods or remediation technologies. 展开更多
关键词 Groundwater pollution Identification of pollution sources Geophysical exploration identification Geochemistry identification Isotopic tracing Numerical modeling Remediation technology Hydrogeological conditions Hydrogeological survey engineering
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Contamination assessment,source apportionment and associated health risks of PTEs in agricultural soil under five land-use patterns in Sanya,China
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作者 Jian-zhou Yang Yan-gang Fu +6 位作者 Qiu-li Gong Sheng-ming Ma Jing-jing Gong Jian-weng Gao Zhen-liang Wang Yong-wen Cai Shi-xin Tang 《China Geology》 CAS CSCD 2024年第3期469-479,共11页
To understand the levels of potentially toxic elements(PTEs)contamination in soils and their effects on human health from different agricultural land use in Sanya,China.128 soil samples(64 topsoil samples and correspo... To understand the levels of potentially toxic elements(PTEs)contamination in soils and their effects on human health from different agricultural land use in Sanya,China.128 soil samples(64 topsoil samples and corresponding subsoil samples)were collected from the five representative land-use patterns.Inductively coupled plasma mass spectrometry(ICP-MS),Atomic fluorescence spectrometry(AFS),and Inductively coupled plasma optical emission spectrometry(ICP-OES)were used to determine the content of PTEs(As,Cd,Hg,Cu,Cr,Ni,Pb,Zn,Co,Mo,Sb,and V).Correlation analysis and factor analysis were used to determine the source of PTEs.Geo-accumulation index(I_(geo)),hazard quotient(HQ),and total carcinogenic risk index(TR)were used to measure the PTEs contamination and its relative health impacts.Results showed that the average values of 12 PTEs in topsoil were higher than the Hainan soil geochemical baseline,showing different degrees of PTEs accumulation effect.The concentration of PTEs in the topsoil was lower than those in the subsoil except for Cd and Hg.The I_(geo)revealed that the major accumulated element in soils was As followed by Mo.Source apportionment suggested that parent materials and agricultural practices were the dominant factors for PTEs accumulation in the topsoil.Noncarcinogenic risks of soil samples from five land-use patterns presented a trend of paddy field>dry field>woodland>orchard>garden plot.However,the HQ values of 12 PTEs were less than the recommended limit of HQ=1,representing that there are no non-carcinogenic risks of PTEs for children and adults in the study area.The TR values are within 6.95×10^(-6)-1.38×10^(-5),which corresponds to the low level.Therefore the PTEs in the agricultural soil of the study area show little influence on the health status of the local population. 展开更多
关键词 Potentially toxic trace elements(PTEs) SOILS Land-use Geo-accumulation index(Igeo) Hazard quotient(HQ) total carcinogenic risk index(TR) source apportionment Health risk Agricutural geological survey engineering
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Impact of external carbon source on A2/O system and its biological phosphorus and nitrogen removal efficiency before and after restoration 被引量:4
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作者 LIU Fangjing DUAN Yitong +2 位作者 ZHAO Jianhui CHENG Guoling LI Yongfeng 《环境污染与防治》 CAS CSCD 北大核心 2014年第4期I0004-I0009,10,共6页
以啤酒废水作为外加碳源,研究了不同浓度外加碳源对A2/O系统的冲击情况,并通过调节工艺参数对系统进行修复,对比了修复前后系统的脱氮除磷效果。结果表明,投加低浓度(COD为50mg/L)外加碳源没有影响系统的正常运行,且有助于提... 以啤酒废水作为外加碳源,研究了不同浓度外加碳源对A2/O系统的冲击情况,并通过调节工艺参数对系统进行修复,对比了修复前后系统的脱氮除磷效果。结果表明,投加低浓度(COD为50mg/L)外加碳源没有影响系统的正常运行,且有助于提高系统的脱氮除磷效率;用COD为150mg/L的啤酒废水对系统进行冲击时,总氮、氨氮、总磷和COD的去除率均有所下降,依次下降了31.53、16.38、7.61、10.19百分点;经过修复后,与冲击前相比较,各分析指标的去除率略有降低。用高浓度(COD为250nag/L)的啤酒废水冲击A2/O系统,冲击期间各分析指标显著下降,且产生轻微的污泥膨胀,修复后各分析指标去除率依次降低了11.75、9.56、21.20、20.79百分点。实验表明,啤酒废水可以作为外加碳源用以调节系统的C/N,且A0/o系统对浓度变化的冲击具有一定的抵抗力。 展开更多
关键词 环境污染 环境防治 环境治理 环境保护 大气污染
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Effect of carbon source and nitrate concentration on denitrifying phosphorus removal by DPB sludge 被引量:6
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作者 WANGYa-yi PENGYong-zhen +1 位作者 WangShu-ying PANMian-li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第4期548-552,共5页
Effect of added carbon source and nitrate concentration on the denitrifying phosphorus removal by DPB sludge was systematically studied using batch experiments, at the same time the variation of ORP was investigated. ... Effect of added carbon source and nitrate concentration on the denitrifying phosphorus removal by DPB sludge was systematically studied using batch experiments, at the same time the variation of ORP was investigated. Results showed that the denitrifying and phosphorus uptake rate in anoxic phase increased with the high initial anaerobic carbon source addition. However once the initial COD concentration reached a certain level, which was in excess to the PHB saturation of poly-P bacteria, residual COD carried over to anoxic phase inhibited the subsequent denitrifying phosphorus uptake. Simultaneously, phosphate uptake continued until all nitrate was removed, following a slow endogenous release of phosphate. High nitrate concentration in anoxic phase increased the initial denitrifying phosphorus rate. Once the nitrate was exhausted, phosphate uptake changed to release. Moreover, the time of this turning point occurred later with the higher nitrate addition. On the other hand, through on-line monitoring the variation of the ORP with different initial COD concentration, it was found ORP could be used as a control parameter for phosphorus release, but it is impossible to utilize ORP for controlling the denitrificaion and anoxic phosphorus uptake operations. 展开更多
关键词 biological phosphorus removal carbon source NITRATE ORP denitrifying phosphorus removal bacteria (DPB) anaerobic-anoxic processes
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Waste Activated Sludge Alkaline Fermentation Liquid as Carbon Source for Biological Nutrients Removal in Anaerobic Followed by Alternating Aerobic-Anoxic Sequencing Batch Reactors 被引量:18
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作者 郑雄 陈银广 刘晨晨 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第3期478-485,共8页
Activated sludge process has been widely used to remove phosphorus and nitrogen from wastewater. However,the nitrogen and phosphorus removal is sometimes unsatisfactory due to the low influent COD.Another problem with... Activated sludge process has been widely used to remove phosphorus and nitrogen from wastewater. However,the nitrogen and phosphorus removal is sometimes unsatisfactory due to the low influent COD.Another problem with the activated sludge process is that large amount of waste activated sludge is produced,which needs further treatment.In this study,the waste activated sludge alkaline fermentation liquid was used as the main carbon source for phosphorus and nitrogen removal under anaerobic followed by alternating aerobic-anoxic conditions,and the results were compared with those using acetic acid as the carbon source.The use of alkaline fermentation liquid not only affected the transformations of phosphorus,nitrogen,intracellular polyhydroxyalkanoates and glycogen, but also led to higher removal efficiencies for phosphorus and nitrogen compared with acetic acid.It was observed that ammonium was completely removed with either alkaline fermentation liquid or acetic acid as the carbon source. However,the former resulted in higher removal efficiencies for phosphorus(95%)and nitrogen(82%),while the latter showed lower ones(87%and 74%,respectively).The presence of a large amount of propionic acid in the alkaline fermentation liquid was one possible reason for its higher phosphorus removal efficiency.Exogenous instead of endogenous denitrification was the main pathway for nitrogen removal with the alkaline fermentation liquid as the carbon source,which was responsible for its higher nitrogen removal efficiency.It seems that the alkaline fermentation liquid can replace acetic acid as the carbon source for phosphorus and nitrogen removal in anaerobic fol- lowed by alternating aerobic-anoxic sequencing batch reactor. 展开更多
关键词 nutrients removal alkaline fermentation liquid waste activated sludge endogenous denitrification carbon source
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Yield, Leaf Senescence, and Cry1Ac Expression in Response to Removal of Early Fruiting Branches in Transgenic Bt Cotton 被引量:1
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作者 DONG He-zhong TANG Wei LI Wei-jiang LI Zhen-huai NIU Yue-hua ZHANG Dong-mei 《Agricultural Sciences in China》 CAS CSCD 2008年第6期692-702,共11页
Two-year field experiments were conducted at Linqing, Yellow River valley of China, to study the plant response to the removal of early fruiting branches in transgenic Bt (Bacillus thuringiensis) cotton (Gossypium ... Two-year field experiments were conducted at Linqing, Yellow River valley of China, to study the plant response to the removal of early fruiting branches in transgenic Bt (Bacillus thuringiensis) cotton (Gossypium hirsutum L.) from 2003 to 2004. Plants were undamaged and treated by removing two basal fruiting branches (FB) at squaring to form the control and the removal treatment, respectively. The plant height, leaf area (LA), dry weight of fruiting forms (DWFF), the number of fruiting nodes (NFN), photosynthetic (Pn) rate, and levels of leaf chlorophyll (Chl), N, P, K, and Cry lAc protein in main- stem leaves were measured at a 10- or 20-d interval after FB removal, and the sink/source ratio as indicated by NFN/LA and DWFF/LA was determined. FB removal significantly increased the plant height, LA, and plant biomass in both years. Lint yields were increased 7.5 and 5.2% by removal compared with their controls in 2003 and 2004, respectively. Significant increases in boll size (5.7 and 5.1%) were also observed in removal than in control for both years. Either NFN/LA or DWFF/LA was significantly reduced by removal before 40 d after removal; however, both NFN/LA and DWFF/LA were significantly enhanced by FB removal at 80 d after removal compared to the untreated control. There was no significant difference in fiber quality in the first two harvests between removal and control, but fiber strength and micronarie in the third harvest were significantly improved by FB removal. In terms of leaf Chl, Pn rate, levels of total N, P, and K in late season, leaf senescence was considerably delayed by FB removal. Levels of CrylAc protein in the fully expanded young leaves were considerably higher in FB-excised plants than in control, indicating FB removal enhanced CrylAc expression. It is suggested that the yield and quality improvement with FB removal may be attributed to the increased NFN/LA or DWFF/LA in late season and delayed leaf senescence, respectively. FB removal can be a potential practice incorporated into the intensive cultivation system for enhancing transgenic Bt cotton production. 展开更多
关键词 branch removal Bt cotton Cry lAc protein leaf senescence photosynthetic rate sink/source ratio
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Spatial variations of Pb,As,and Cu in surface snow along the transect from the Zhongshan Station to Dome A,East Antarctica
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作者 XingXing Jiang ShuGui Hou +8 位作者 YuanSheng Li HongXi Pang Rong Hua Mayewski Paul Sneed Sharon ChunLei An Handley Michael Ke Liu WangBin Zhang 《Research in Cold and Arid Regions》 CSCD 2018年第3期219-231,共13页
The spatial distributions of lead, arsenic, and copper (Pb, As, and Cu, respectively) in surface snow along the transect from the Zhongshan Station to Dome A, East Antarctica, are presented. The mean concentrations ... The spatial distributions of lead, arsenic, and copper (Pb, As, and Cu, respectively) in surface snow along the transect from the Zhongshan Station to Dome A, East Antarctica, are presented. The mean concentrations of Pb, As, and Cu are 1.04±1.56 pg/g, 0.39±0.08 pg/g, and 11.2±14.4 pg/g, respectively. It is estimated that anthropogenic contributions are dominant for Pb, As, and Cu. Spatially, Pb concentrations show an exponentially decreasing trend from the coast inland, while a moderate decreasing trend is observed for Cu concentrations in the coastal area (below 2,000 m above sea level (a.s.1.)). In the intermediate area (2,000-3,000 m a.s.1.), the concentrations and enrichment factors of all these elements show high variability due to the complicated characteristics of climate and environment. On the inland plateau (above 3,000 m a.s.1.), the high concentrations of As and Pb are induced by high deposition efficiency, the existence of polar stratospheric precipitation, and the different fraction deposition to East Antarctica. The extremely high concentrations with maximum values of 9.59 pg/g and 69.9 pg/g for Pb and Cu, respectively, are suggested to result mainly from local human activities at the station. Our results suggest that source, transport pathway, and deposition pattern, rather than distance from the coast or altitude, lead to the spatial distributions of Pb, As, and Cu; and it is further confirmed by spatial variations of the three metals deposited over the whole continent of Antarctica. 展开更多
关键词 ANTARCTICA surface snow trace metals spatial variations source and transportation
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Chemical Composition and Source Characterization of Hailstones in Dhaka, Bangladesh
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作者 Rasheda Aktar Samiha Morshad Ahmed +1 位作者 Mohammad Shohel Abdus Salam 《Journal of Geoscience and Environment Protection》 2018年第9期71-82,共12页
A comprehensive analysis on the chemical composition and source apportionment of hailstone samples were conducted in Dhaka, Bangladesh. pH, electrical conductivity (EC), total dissolved solids (TDS), water soluble ion... A comprehensive analysis on the chemical composition and source apportionment of hailstone samples were conducted in Dhaka, Bangladesh. pH, electrical conductivity (EC), total dissolved solids (TDS), water soluble ions (Na+, K+, Ca2+, Mg2+, Cl-, SO42-, NO3-, HCO3-) and trace metals (Zn, Fe, Cu, Mn) of hailstone were determined. The result revealed that the average pH, EC, TDS were 6.95 ± 0.54, 356.3 ± 150.6 μS·cm-1 and 17.5 ± 2.89 mg·L-1, respectively. The water soluble ions followed the order: Ca2+ > Cl-1 > SO42- > HCO3- > Na+ > Mg2+ > K+ > NO3-. The concentrations of trace metals ranged in order with Zn > Fe > Cu, while the concentration of Mn was below detection limit. Sodium adsorption ratio (SAR) was 0.20 ± 0.09 meqL-1 which indicates it is benign to plants and safe for irrigation. The order of neutralization factor (calculated with average concentrations) found in hailstone was NFCa(1.16) > NFMg (0.36) > NFK(0.32) which were originated from earth crust. Notable correlation was found in between soil tracers Ca2+ and Mg2+ (r = 0.87), indicating their common source dust. Enrichment factor analysis revealed that Ca2+, Mg2+ and K+ are mainly from crust, whereas NO3- and SO42- are mainly attributable to anthropogenic origins. Further source contribution analysis revealed that anthropogenic actions accounted for 99.2% of total NO3- and 89.6% of total SO42-, while 99.2% of total Ca2+ and 95% Mg2+ were from crustal source. 展开更多
关键词 Hailstone Water SOLUBLE ION TRACE Metal source APPORTIONMENT
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Adsorption experiment of water-soluble rare earth elements in atmospheric depositions and implications for source tracing in South China
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作者 Xiaojian Mi Yuan Li +4 位作者 Yuefeng Liu Yu Xie Hanjie Li Xiaotao Peng Houyun Zhou 《Acta Geochimica》 EI CAS CSCD 2021年第2期225-233,共9页
The distribution patterns of rare earth elements(REEs)in fine-grained materials in various depositions were often found to be similar to those of the aeolian sediments deposited in the Loess Plateau in North China and... The distribution patterns of rare earth elements(REEs)in fine-grained materials in various depositions were often found to be similar to those of the aeolian sediments deposited in the Loess Plateau in North China and the fine-grained materials were suggested to be derived from wind-blown dust.However,increasing evidence indicated that the REEs in the water-soluble portion of atmospheric depositions also displayed similar patterns to those of aeolian sediments.In this study,water-soluble REEs in three atmospheric depositions collected from different climatic zones in China were adsorbed with two adsorbents with distinct adsorption capacity,glass powder,and co-precipitated iron hydroxide.The results showed that the REEs adsorbed by the two adsorbents displayed patterns similar to those of the original atmospheric depositions.The typical characteristics of the REE patterns of atmospheric deposition can be well reproduced in the adsorbed REEs.The higher the REE concentrations in the atmospheric depositions,or the higher adsorption efficiency of the adsorbents,the better reproducibility of the REEs patterns.The results suggest that the REEs of the fine-grained materials in various sediments,which have a high adsorption capacity,especially those deposited in South China,may come from the water-soluble REEs in atmospheric deposition,and may not be appropriate tracers of wind-blown dust from North China. 展开更多
关键词 Atmospheric deposition Rare earth element Adsorption experiment source tracing Fine-grained material
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Mineralogy and geochemistry of sands of the lower course of the Sanaga River, Cameroon: implications for weathering,provenance, and tectonic setting
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作者 Marie Therese Nanga Bineli Vincent Laurent Onana +2 位作者 Sylvie Desiree Noa Tang Yves Robert Bikoy Georges Emmanuel Ekodeck 《Acta Geochimica》 EI CAS CSCD 2021年第3期348-365,共18页
This study focuses on the mineralogy and bulk chemical composition of 19 sediment samples,collected from the Sanaga River bed,between Nanga-Eboko and the Atlantic Ocean in Cameroon,to infer provenance,weathering,and t... This study focuses on the mineralogy and bulk chemical composition of 19 sediment samples,collected from the Sanaga River bed,between Nanga-Eboko and the Atlantic Ocean in Cameroon,to infer provenance,weathering,and tectonic setting.The textural analysis revealed that these sediments are mainly coarse-grained sands.X-ray diffraction and heavy mineral analyses show that these sands are made of quartz,microcline,plagioclase,muscovite,ilmenite,anatase,magnetite,opaques,and epidote.The Index of Chemical Variability values(1.07–2.68)indicates that the sands are immature.The Chemical Index of Alteration(53–66%),Plagioclase Index of Alteration(PIA;57–75%),and Mafic Index of Alteration(54–67%)values revealed a moderate intensity of weathering for these sediments.According to the compositional maturity diagram,the sands are mainly litharenites.The studied sands show enrichment in light rare earth elements relative to heavy rare earth elements and a negative anomaly in Eu(Eu/Eu*=0.32–0.83).These sands were derived from felsic metamorphic rocks dated Meso to Neoproterozoic from the Pan-African(700–1000 Ma)domain of south Cameroon.Th/U ratios(mean=5.40;n=19)reveal that these sands originating from felsic source rocks and are low to moderately recycled.On the tectonic discrimination diagrams,all the samples are plotted in the rift and passive margin domains,which is consistent with the tectonic history of Pan African in southern Cameroon. 展开更多
关键词 Central Africa Sanaga River sediments Heavy minerals Major and trace elements source rocks Rift and passive setting
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Isotopic tracing of ore-forming source materials for Dexing porphyry copper deposit of Jiangxi, China
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作者 Peng QIAN Jianjun LU 《Global Geology》 2008年第1期25-31,共7页
Dexing copper deposit is the biggest porphyry copper deposit in China. By researching isotopes of C,Si and Cu from the samples of Tongchang and Fujiawu ore-field, the authors found that δ13CPDB values of siderite wer... Dexing copper deposit is the biggest porphyry copper deposit in China. By researching isotopes of C,Si and Cu from the samples of Tongchang and Fujiawu ore-field, the authors found that δ13CPDB values of siderite were close to the δ13CPDB value of original magma; δ30Si values of the samples at the ore-forming stage were close to the δ30Si value range of magma, δ30Si values of partial samples were far away from it; Cu isotopic compositions of massive chalcopyrite formed at the early ore-forming stage are higher than that of veinal chalcopyrite formed at the later ore-forming stage. The results show that ore-forming materials were mainly derived from the porphyry body, and part of them were from wall rock materials. 展开更多
关键词 Dexing copper deposit source material isotope tracing
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Cross-and counter-current treatment systems for the removal of equilibrium constrained metals on unconventional sorbants [Bauxsol (TM)]
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作者 Malcolm W. Clark Jim Jonas +2 位作者 David M. McConchie Jim Rouse Christa Whitmore 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期127-127,共1页
关键词 微量金属 去除方法 清洁生产 地下水 水文化学
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Source Strata of Gold in Western Guangdong— Their Identification and Significance in Gold Mineralization
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作者 陆建军 吴劲薇 翟建平 《Chinese Journal Of Geochemistry》 EI CAS 1995年第4期336-345,共10页
Strata of different geological periods extensively outcrop in western Guang-dong Province, but most gold deposits are restricted to the Middle-Late Proterozoic Yunkai Group and the Cambrian Bacun Group,showing obvious... Strata of different geological periods extensively outcrop in western Guang-dong Province, but most gold deposits are restricted to the Middle-Late Proterozoic Yunkai Group and the Cambrian Bacun Group,showing obvious strata-boun character-istics .Gold abundance and trace element geochemistry of the Yunkai and Bacun Groups are compared with those of the Ordovician and Silurian strta.The Yunkai Group is considered to be the source strata for gold mineralization in the region. 展开更多
关键词 地层 云开组 广东 示踪元素 寒武纪 志留纪 成矿作用 富集
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Approach to estimating non-point pollutant load removal rates based on water environmental capacity: a case study in Shenzhen 被引量:1
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作者 刘梁 刘安 管运涛 《Journal of Southeast University(English Edition)》 EI CAS 2014年第2期143-149,共7页
An innovative approach based on water environmental capacity for non-point source NPS pollution removal rate estimation was discussed by using both univariate and multivariate data analysis.Taking Shenzhen city as the... An innovative approach based on water environmental capacity for non-point source NPS pollution removal rate estimation was discussed by using both univariate and multivariate data analysis.Taking Shenzhen city as the study case a 67% to 74% NPS pollutant load removal rate can lead to meeting the chemical oxygen demand COD pollution control target for most watersheds.In contrast it is hardly to achieve the ammonia nitrogen NH4-N total phosphorus TP and biological oxygen demand BOD5 pollution control target by simply removing NPS pollutants. This highlights that the pollution control strategies should be taken according to different pollutant species and sources in different watersheds rather than one-size-fits-all . 展开更多
关键词 environmental capacity estimation non-point source (NPS) pollution removal rate control strategy
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Sources appointment and health risks of PM_(2.5)-bound trace elements in a coastal city of southeastern China 被引量:1
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作者 Ziyi Lin Xiaolong Fan +8 位作者 Gaojie Chen Youwei Hong Mengren Li Lingling Xu Baoye Hu Chen Yang Yanting Chen Zhiqian Shao Jinsheng Chen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第4期561-571,共11页
To gain a comprehensive understanding of sources and health risks of trace elements in an area of China with high population densities and low PM_(2.5)concentrations,15 trace elements(Al,K,Ca,Ti,V,Cr,Mn,Fe,Ni,Cu,Zn,As... To gain a comprehensive understanding of sources and health risks of trace elements in an area of China with high population densities and low PM_(2.5)concentrations,15 trace elements(Al,K,Ca,Ti,V,Cr,Mn,Fe,Ni,Cu,Zn,As,Sn,Ba,Pb)in PM_(2.5)were monitored from December 2020 to November 2021 in a representative city,Xiamen.The concentrations of trace elements in Xiamen displayed an obvious seasonal variation and were dominated by K,Fe,Al,Ca and Zn.Based on Positive Matrix Factorization analysis,source appointment revealed that the major sources of trace elements in Xiamen were traffic,dust,biomass and firework combustion,industrial manufacture and shipping emission.According to health risk assessment combined with the source appointment results,it indicated that the average noncarcinogenic risk was below the threshold and cancer risk of four hazardous metals(Cr,Ni,As,Pb)exceeded the threshold(10^(-6)).Traffic-related source had almost half amount of contribution to the health risk induced by PM_(2.5)-bound trace elements.During the dust transport period or Spring Festival period,the health risks exceeded an acceptable threshold even an order of magnitude higher,suggesting that the serious health risks still existed in low PM_(2.5)environment at certain times.Health risk assessment reminded that the health risk reduction in PM_(2.5)at southeastern China should prioritize traffic-related hazardous trace elements and highlighted the importance of controlling vehicles emissions in the future. 展开更多
关键词 PM_(2.5)-bound trace elements Seasonal variations source appointment Health risks Traffic-related source
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Fine particle trace elements at a mountain site in southern China:Source identification,transport,and health risks
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作者 Jiaoping Xing Runping Ding +5 位作者 Feifeng Chen Linyu Peng Wenhua Wang Xiaoyan Song Qing Ye Yuanqiu Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第7期166-181,共16页
Trace elements in atmospheric particulate matter play a significant role in air quality,human health,and biogeochemical cycles.In this study,the trace elements(Ca,Al,K,Fe,Na,Mg,Zn,Pb,Mn,Ti,Cu,Cr,Sr,Ni)in PM2.5samples ... Trace elements in atmospheric particulate matter play a significant role in air quality,human health,and biogeochemical cycles.In this study,the trace elements(Ca,Al,K,Fe,Na,Mg,Zn,Pb,Mn,Ti,Cu,Cr,Sr,Ni)in PM2.5samples collected at the summit of Mt.Lushan were analyzed to quantify their abundance,source,transport,and health risks.During the whole sampling period,the major trace elements was Ca,Al,and K.While the trace metals with the lowest concentrations were Sr,Ni,Rb,and Cd.The trace elements were influenced by air mass transport routes,exhibiting an increasing trend of crustal elements in the northwesterly airmass and anthropogenic elements(Zn,Mn,Cu,and Ni)in the easterly air masses.Construction dust,coal+biomass burning,vehicle emission,urban nitrate-rich+urban waste incineration emissions,and soil dust+industry emissions were common sources of PM2.5on Mt.Lushan.Different air mass transport routes had various source contribution patterns.These results indicate that trace elements at Mt.Lushan are influenced by regional anthropogenic emissions and monsoon-dominated trace element transport.The total resulting cancer risk value that these elements posed were below the acceptable risk value of 1×10^(-6),while the non-carcinogenic risk value(1.72)was higher than the safety level,suggesting that non-carcinogenic effects due to these trace elements inhalation were likely to occur.Vehicle emission and coal+biomass burning were the common dominant sources of non-cancer risks posed by trace elements at Mt.Lushan. 展开更多
关键词 Trace elements Risk assessment Cluster analysis source apportionment
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