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Natural and Artificial Radionuclides in River Bottom Sediments and Suspended Matter in the Czech Republic in the Period 2000-2010
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作者 Eduard Hanslik Diana Maresova Eva Juranova 《Journal of Environmental Protection》 2014年第2期114-119,共6页
The concentrations of natural radionuclides, radium-226, radium-228, and potassium-40, and the artificial radionuclide caesium-137, in river bottom sediments and suspended matter were monitored in the Czech Republic b... The concentrations of natural radionuclides, radium-226, radium-228, and potassium-40, and the artificial radionuclide caesium-137, in river bottom sediments and suspended matter were monitored in the Czech Republic by the Czech Hydrometeorological Institute during the period 2000-2010 and 2001-2010 respectively. The data were used to evaluate the natural background levels of these radionuclides and the impact of human activities on the water environment. For potassium-40 in sediments, the natural background level was estimated to be 570 Bq/kg. To evaluate the background level for radium-226, the river sites affected by human activities (mining and processing uranium ore, coal) were eliminated from the assessment. The average natural background values were 47.8 Bq/kg for radium-226 and 47.2 Bq/kg for radium-228 in sediments and 86.5 Bq/kg for radium-226 and 87.9 Bq/kg for radium-228 in suspended matter. The river sediments were identified as good indicators of radioactive contamination, especially radium-226, which recorded historic contamination due to former uranium mining and milling. The radium-226 contamination rate was assessed using the ratio of radium-226 to radium-228. This ratio was used to classify sediment according to the relative contamination from the uranium industry. The residual contamination of caesium-137 due to the Chernobyl accident in 1986 was also assessed. Average values of caesium-137 were 14.0 Bq/kg in sediments and 25.0 Bq/kg in suspended matter. 展开更多
关键词 River Bottom Sediments suspended matter Surface Water Uranium Industry Radioactive Contamination Radium-226 Radium-228 Potassium-40 Caesium-137
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Heavy metals pollution in water,suspended matter and surface sediment in typical mountainous urban river:A case study in Qingshui Stream in Chongqing,China 被引量:4
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作者 何太蓉 李百战 +1 位作者 李贤良 刘存东 《Journal of Central South University》 SCIE EI CAS 2009年第S1期286-291,共6页
Based on a detailed environmental investigation of the whole Qingshui Stream catchments,samples of water and surface sediments were collected at 15 different places from the upper to the lower reaches of Qingshui Stre... Based on a detailed environmental investigation of the whole Qingshui Stream catchments,samples of water and surface sediments were collected at 15 different places from the upper to the lower reaches of Qingshui Stream,and samples of suspended matter were obtained by filtrating the water samples. The concentrations of heavy metals (Cd,Cu and Zn) were measured in filtered water,suspended matter,and surface sediment by ICP-AES. The results show that the concentrations of the three heavy metals in filtered water are 0.18,6.6 and 17.67 μg/L,lower than that of the Fresh Water Quality Criteria (US EPA) and those of the plain urban rivers,but the contents of Cd,Cu and Zn are much higher than the mean values of rivers in the world and the background value in Jialing River basin. The heavy metals concentrations in the suspended matter from Qingshui Stream are 2.08,438.14 and 1 348.05 mg/kg,much higher than the corresponding background values of soils in Chongqing city. The heavy metals concentrations in the surface sediment from Qingshui Stream are 0.84,189.75 and 838.23 mg/kg,and the values of index of geoaccumulation Igeo of Cd,Cu and Zn show that their pollution degrees are moderate. The heavy metals exist in three transferable forms such as water,suspended matter and surface sediment in Qingshui Stream. The heavy metals concentrations in water are the lowest,and those in the suspended matter are the highest,so the ecological risk in suspended matter is the highest. The distribution tendencies of three metals in water,suspended matter and surface sediment in main riverbed are different. 展开更多
关键词 heavy metal WATER suspended matter surface sediment POLLUTION Qingshui STREAM
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RECENT SEDIMENTATION AND SUSPENDED MATTER IN ERHAI LAKE,YUNNAN PROVINCE,CHINA 被引量:2
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作者 孙顺才 张琛 宋学良 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1999年第2期170-180,共11页
Ths study on the physico-geograpical environment of Erhai Lake focused on the suspended matter and recent deposition rates, 14 C, 210 Pb and 137 Cs methods were used to determine the ageand sedimentation rate, which w... Ths study on the physico-geograpical environment of Erhai Lake focused on the suspended matter and recent deposition rates, 14 C, 210 Pb and 137 Cs methods were used to determine the ageand sedimentation rate, which was found to be 0.5 t0 2.0 mm/a, average of 0.9 mm/a. The authors calculated the budget of some elements by studying the deposition, and fuUnd that about 30% of nitrogen,and most of the phosphorous, were transported into the lake by the ediments. 展开更多
关键词 Erhai LAKE suspended matter SEDIMENTATION RATE
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TRANSPORT OF SUSPENDED MATTER FROM THE CHANGJIANG RIVER TO THE EAST CHINA SEA SHELF 被引量:2
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作者 李凡 李平 +1 位作者 张秀荣 姜秀珩 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1997年第3期264-270,共7页
Suspended matter (SM) in the East China Sea (ECS) shelf seawater was investigated during Oct. 1993, Apr. and Oct. 1994. Results showed that the high total suspended matter(TSM) region (>7200)mg/L) was limted to nea... Suspended matter (SM) in the East China Sea (ECS) shelf seawater was investigated during Oct. 1993, Apr. and Oct. 1994. Results showed that the high total suspended matter(TSM) region (>7200)mg/L) was limted to near the estuary and reduced rapidly to <10 mg/L at 122 °30’E. The high TSM contour extended mainly NE in surface water but SE in near bottom Water,i. e., SM transport from the Changjiang River was characterized by "stratification and different transport directions in different layers’. TSM distribution on sections showed that the up-climbing Kuroshio water prevents Changjiang River SM in middle and bottom water from transporting to the Okinawa Trough. Vertical distributions of the TSM showed a suspended-cline that appeared in the inner and middle shelf TSM below it was dense and formed a turbid water laper, TSM above it was less dense, so the water was reatively clear. Formation of the suspended-cline correlated with high density current and resuspension of bottom sediment. 展开更多
关键词 SEDIMENT TRANSPORT suspended matter EAST China SEA SHELF
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Temporal-Spatial Variation of Surface Suspended Matter and Controlling Factors in the Inner Shelf of the East China Sea in Winter 被引量:2
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作者 MIN Jianxiong LI Guangxue +6 位作者 DING Dong QIAO Lulu MA Yanyan YANG Gang ZHANG Yaqi ZHANG Lei LI Shuhao 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第1期9-19,共11页
Based on the observed surface suspended matter in the East China Sea in February 2007 and June 2015, an empirical model was established using L1 b's band 4 data to retrieve surface suspended matter from the Modera... Based on the observed surface suspended matter in the East China Sea in February 2007 and June 2015, an empirical model was established using L1 b's band 4 data to retrieve surface suspended matter from the Moderate Resolution Imagine Spectroradiometer Terra imagery. The squared correlation coefficient is 0.8358, and the root mean square error is 0.4285 mg L-1. The model reflects the distribution characteristics of surface suspended matter in the inner shelf of the East China Sea. In this paper, the satellite images of the study area were retrieved in January from 2001 to 2015, and the monthly distribution of surface suspended matter were obtained. The inter-annual distribution of the study area is similar, and the concentration of surface suspended matter is higher near the shore than offshore. A large amount of surface suspended matter is transported southeast under the influence of Zhejiang and Fujian coastal current and Taiwan warm current. Only a small amount of surface suspension can reach the Kuroshio area. The surface suspended matter concentration changes obviously near the estuary because of the effect of differences in the flux of the Yangtze River. Meanwhile, winter monsoon, temperature front, El Ni?o events, and other factors affect the distribution of surface suspended matter in 100 m isobath to coastal water but minimally influence the distribution in 100 m isobath to deep sea. 展开更多
关键词 inner shelf of the East China Sea Moderate Resolution IMAGINE SPECTRORADIOMETER SURFACE suspended matter MONTHLY distribution INTER-ANNUAL VARIATION
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Estimation of total suspended matter in the Zhujiang (Pearl) River estuary from Hyperion imagery 被引量:3
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作者 刘大召 付东洋 +1 位作者 徐兵 沈春燕 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第1期16-21,共6页
Although remote sensing data have been used to estimate total suspended matter (TSM) in coastal waters, it has limitations when applied to estuary waters in low spatial resolution situations. The spatial resolution of... Although remote sensing data have been used to estimate total suspended matter (TSM) in coastal waters, it has limitations when applied to estuary waters in low spatial resolution situations. The spatial resolution of ocean color satellites such as SeaWiFS and MODIS is usually ~1 km, and therefore is not adequate for small, local-scale areas such as the Zhujiang (Pearl) River estuary. In contrast, 30 m-resolution EO-1 Hyperion imagery has potential for studying TSM in localized areas. We measured the surface spectral radiance reflectance of the river estuary water in the visible and near infra-red spectral range. Sensitivity analysis indicated that the ratio of remote sensing reflectance at 813 nm (Rrs(813)) to reflectance at 559 nm (Rrs(559)) could be used to estimate TSM concentration, and a linear relationship was established between the ratio and in-situ TSM concentration. We applied the linear relationship to Hyperion imagery to map TSM concentration in the estuary. The Hyperion imagery provided sufficient spatial resolution to detect spatiotemporal changes in TSM concentrations in the estuary small estuary area. This study demonstrated the usefulness of Hyperion imagery for mapping the distribution of TSM in estuary waters. 展开更多
关键词 HYPERION 珠江河口 图像映射 总悬浮颗粒物 估计 空间分辨率 悬浮物浓度 SEAWIFS
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Numerical Study of Water and Suspended Matter Exchange Between the Yellow Sea and the East China Sea 被引量:6
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作者 庞重光 白学志 胡敦欣 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2003年第3期214-221,共8页
POM was used to study the monthly mean circulation in the Yellow Sea and East China Sea. The calculated results showed almost all major characteristics of the circulation system. The calculated circulation system and ... POM was used to study the monthly mean circulation in the Yellow Sea and East China Sea. The calculated results showed almost all major characteristics of the circulation system. The calculated circulation system and observational data were used to determine the sediment concentration, volume transport, heat flux and suspended matter flux between the Yellow Sea and the East China Sea. The conclusions obtained were that the volume and heat are transported northward through the 32°N section during each season; that in winter and autumn, total suspended matter is transported southward, and is larger in winter than in autumn. The reason is that the Yellow Sea Coastal Current is strong and always contains more suspend matter in winter and autumn. The seasonal suspended matter exchange between the Yellow Sea and the East China Sea are 0.58×10 7 tons in spring, 2.81×10 7 tons in summer, -2.60×10 7 tons in autumn and -3.40×10 7 tons in winter. Net flux of suspended matter from the Yellow Sea to the East China Sea is 2.61×10 7 tons every year. 展开更多
关键词 黄海 中国东海 水变化 数值模拟 悬浮物质流动 海洋动力学
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Retrieval of Total Suspended Matters Using Field Spectral Data in Shitoukoumen Reservoir,Jilin Province,Northeast China 被引量:2
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作者 XU Jingping ZHANG Bai +4 位作者 LI Fang SONG Kaishan WANG Zongming LIU Dianwei ZHANG Guangxin 《Chinese Geographical Science》 SCIE CSCD 2009年第1期77-82,共6页
From August to October in 2006,three times of field spectral measurements with a Field Spec FR spectroradiometer(Analytical Spectral Devices,Inc.,USA) were carried out in Shitoukoumen Reservoir,Jilin Province,Northeas... From August to October in 2006,three times of field spectral measurements with a Field Spec FR spectroradiometer(Analytical Spectral Devices,Inc.,USA) were carried out in Shitoukoumen Reservoir,Jilin Province,Northeast China. Owing to the serious soil and water loss in the upstream,reflectance curves of the reservoir were characterized by high concentrations of total suspended matter(TSM) . Extending the spectral analysis to 1200nm in the near-infrared band,this research revealed an obvious reflectance peak around 1070nm which was caused by the strong backscattering of high TSM. The method of partial least squares(PLS) regression was applied to retrieving the TSM. Reflectance in two spectral bands,i.e.,675-948nm and 1029-1105nm,were used as variables to develop PLS models. Traditional linear regression,first derivative model and logarithmic model were also used for the comparison of different models. Results showed that the PLS model based on Rrs(675) -Rrs(948) gave out best results with high precision and stability. Although the PLS model based on Rrs(1029) -Rrs(1105) did not have an outstanding performance due to lots of noise,the reflectance peak in the near-infrared band was an important TSM feature and its efficient exploitation would have a considerable significance in TSM remote sensing. 展开更多
关键词 水库 土壤 水量消耗 光谱分析 遥感技术
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VARIATIONS OF THE SUSPENDED MATTER AND THE PARTICULATE ORGANIC CARBON IN THE ENTRY OF THE GIRONDE ESTUARY, FRANCE
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作者 林荣根 EtcheberHenri 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1994年第1期54-60,共7页
The effects of using different types of glass fiber filters (GF/F, GF/C) and of sample treatments evaluated. Studies on the variation of suspended matter (SM) and particulate organic carbon (POC) showed that: 1) the t... The effects of using different types of glass fiber filters (GF/F, GF/C) and of sample treatments evaluated. Studies on the variation of suspended matter (SM) and particulate organic carbon (POC) showed that: 1) the transversal and day to night variations are important and must be taken into account in order to get a corrcet river flux; 2) no regular seasonal variations of SM and POC observed, as they are controlled essentially by the climatological, hydrologic, physiochernical, biological, and geological conditions of the drainage area. 展开更多
关键词 suspended matter PARTICULATE organic carbon Gironde ESTUARY variation filter POROSITY sample treatment
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Heavy metals in suspended matters during a tidal cycle in the turbidity maximum around the Changjiang(Yangtze) Estuary 被引量:1
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作者 ZHANG Huaijing ZHAI Shikui +2 位作者 ZHANG Aibin ZHOU Yonghua YU Zenghui 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第10期36-45,共10页
In order to discuss the content distributions and fluxes of heavy metals in suspended matters during a tidal cycle in the turbidity maximum around the Changjiang(Yangtze) Estuary,the contents of heavy metals(Zn,Pb,Cd,... In order to discuss the content distributions and fluxes of heavy metals in suspended matters during a tidal cycle in the turbidity maximum around the Changjiang(Yangtze) Estuary,the contents of heavy metals(Zn,Pb,Cd,Co and Ni) have been analyzed.During a tidal cycle,the average contents of heavy metals are in the order of Zn>Ni>Pb>Co àCd.The average contents in ebb tide are generally higher than that in flood tide.However,at the inshore Sta.11,influenced by the contamination from the nearby waste treatment plant,the average contents of Zn and Ni in flood tide are higher than those in ebb tide and at the offshore Sta.10,the content of Cd in flood tide higher than that in ebb tide due to marine-derived materials.The five heavy metals,mainly terrigenous,are transported towards east-northeast,and settle down with suspended matters in the area between Sta.11 and Sta.10.Influenced by marine-derived materials,the flux value of Cd does not alter significantly with obviously changing in flux direction towards northwest.The source of heavy metals,the salinity of water and the concentration of suspended matters are the main factors controlling the content distributions of heavy metals during a tidal cycle.There is a positive correlation between the contents of heavy metals(Zn,Pb,Co and Ni) and the salinity of water,while the opposite correlation between the contents and the concentrations of suspended matters.Because of marine-derived materials,the content of Cd is not correlated with the concentration of suspended matters and the salinity of water. 展开更多
关键词 重金属含量 悬浮物浓度 最大浑浊带 潮汐周期 长江 平均含量 垃圾处理厂 镉含量
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Observations on carbon and nitrogen content of suspended matter in a headwater stream in Hong Kong
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作者 M.R.Peart GUANDong-sheng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第4期533-538,共6页
The total carbon(C) and total nitrogen(N) content of suspended matter in a small undisturbed headwater drainage basin in the New Territories of Hong Kong has been monitored. Mean C and N contents were 12.85% and 0.99%... The total carbon(C) and total nitrogen(N) content of suspended matter in a small undisturbed headwater drainage basin in the New Territories of Hong Kong has been monitored. Mean C and N contents were 12.85% and 0.99% respectively for 132 samples. Samples collected under stableflow conditions had mean C and N contents of 12.81% and 1.06% respectively. Stormflow samples had mean C and N values of 12.86% and 0.97% respectively, which were very similar to the levels observed under stableflow conditions. The mean C∶N ratios of 12.47 and 13.39 for stableflow and stormflow also reveal little difference according to hydrologic conditions. When all the data is considered little difference is observed in C and N according to the season. However, in winter there is a significant difference in C and N content between stable and stormflow samples. When C and N are plotted against water level the scattergraphs suggested that as stage increases the percentage of C and N in the suspended matter declines. Scattergraphs of C and N against suspended sediment concentration reveal a negative association. Comparison has been made between fresh leaf C, N and C/N ratio for trees and shrubs and the suspended matter. Fresh leaves do not appear to contribute significantly to suspended matter. The C/N ratio of suspended matter would also seem to exclude woody material and algae as sources of suspended matter. 展开更多
关键词 香港 水体 环境监测 环境保护
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Mineralogical properties of the suspended matter in the Yangtze River: Correlations with seasonality
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作者 Changping MAO Junfeng JI Jun CHEN Liang ZHAO 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期275-275,共1页
关键词 矿物 长江 矿化作用 悬浮物质
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A study on suspended matters in the South Huanghai Seain summer time
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作者 J. D. Milliman 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第1期83-95,共13页
A joint investigation of marine geoloy in the South Huanshai Sea was carried out by the Institute of Oceanology, Academia Sinica, and the Woods Hole Oceanographic Institution, USA during 1983~1984. This paper reports... A joint investigation of marine geoloy in the South Huanshai Sea was carried out by the Institute of Oceanology, Academia Sinica, and the Woods Hole Oceanographic Institution, USA during 1983~1984. This paper reports the investigation results of the suspended matters in the water column at 55 stations in July, 1984 (summer time). The highest concentration region where the value is less than 0.5 mg/L, is found in the central part of the study area and the southern part of Shandong Peninsula. The Taiwan Warm Current which might obstruct the discharge of the Changjiang River to the east of the sea, appears in the distribution of the suspended matters outside the Changjiang River Estuary. Although lots of materials are brought into the sea during the high flow period of the Huanghe and the Chansjiang Rivers in July, this does not form the main scarce of the suspended matters. The main source is the resuspension of depesits. The materials brought by rivers come the second, and biogeneons components in the sea 展开更多
关键词 suspended RIVERS brought Shandong INSTITUTION discharged scarce Jiangsu OUTSIDE GRANULES
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Evaluation of the retrieval of total suspended matter concentration in Taihu Lake,China from CBERS-02B CCD
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作者 张民伟 董庆 +1 位作者 唐军武 宋庆君 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第6期1316-1322,共7页
Remote sensing techniques is used to quantify the total suspended matter concentration(CTSM).In this study,we used remotely sensed data to retrieve the CTSM for the Taihu Lake,China,and developed an atmospheric correc... Remote sensing techniques is used to quantify the total suspended matter concentration(CTSM).In this study,we used remotely sensed data to retrieve the CTSM for the Taihu Lake,China,and developed an atmospheric correction algorithm especially for CBERS-02B CCD data.We simulated the remote sensing reflectance(Rrs) of CCD bands using in-situ observations made in a cruise over the Taihu Lake in autumn 2004,from which a retrieval model is established with simulated Rrs(830) and measured CTSM.In addition,we applied the atmospheric correction algorithm and retrieval model to process the CCD data over the lake in 2008 and to retrieve the CTSM.The RMS relative error between the CTSM retrieved from MODIS and from the CCD images is about 42.9%,indicating that algorithms described in this paper can be used for the application of CCD data in monitoring the CTSM distribution in the Taihu Lake. 展开更多
关键词 中巴地球资源卫星 CCD数据 悬浮物浓度 太湖 中国 检索模型 评价 校正算法
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Fronts and transport of suspended matter in the Hangzhou Bay
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作者 Su Jilan Wang Kangshan and Li Yan Second Institute of Oceanography, State Oceanic Administration, Hangzhou 310012, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1993年第1期1-15,共15页
A persistent, year-round NE-SW front is found to exist inside the Hangzhou Bay. This front is actually the merging of the secondary Changjiang plume front from the bay mouth and the Qiantang plume front from the upstr... A persistent, year-round NE-SW front is found to exist inside the Hangzhou Bay. This front is actually the merging of the secondary Changjiang plume front from the bay mouth and the Qiantang plume front from the upstream side of the bay. During neap tides low runoff periods these two plumes can readily be identified. Our findings suggest that suspended matter is transported into the bay through the north end by the secondary Changjiang plume. The front inside the bay acts the part of concentrating suspended matter, and also plays an important role in both the fine-grained sediment and heavy metal distributions in this sedimentary basin. 展开更多
关键词 suspended Hangzhou TIDAL sedimentary TIDES winter MERGING salinity UPSTREAM runoff
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Using Natural Radionuclides to Trace Sources of Suspended Particles in the Lower Reaches of the Yellow River
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作者 ZHANG Han BURNETT CWilliam +5 位作者 ZHANG Xiaojie ZHAO Shibin YANG Disong NAN Haiming YU Zhigang XU Bochao 《Journal of Ocean University of China》 CAS CSCD 2024年第1期99-108,共10页
Natural radionuclides are powerful tools for understanding the sources and fate of suspended particulate matter(SPM).Particulate matter with different particle sizes behaves differently with respect to adsorption and ... Natural radionuclides are powerful tools for understanding the sources and fate of suspended particulate matter(SPM).Particulate matter with different particle sizes behaves differently with respect to adsorption and desorption.We analyzed the activi-ties and distribution characteristics of multiple natural radionuclides(238U,226Ra,40K,228Ra,7Be and 210Pbex)on size-fractionated SPM at the Lijin Hydrographic Station(Huanghe or Yellow River)every month over a one-year period.Results showed that medium silt(16–32µm)was the main component.As expected,the activity of each radionuclide decreased with an increase of particle size.We examined the sources of SPM with different particle sizes using activity ratios of 226Ra/238U,228Ra/226Ra,40K/238U and 7Be/210Pbex,and concluded that SPM with different particle sizes originated from different sources.Our results indicate that fine SPM(<32µm)was mainly from the erosion of soil along the lower reaches of the Yellow River,while coarse SPM(>32µm)was mainly derived from resuspension of riverbed sediment.During high runoff periods,the concentration of SPM increased significantly,and the pro-portion of fine particles originating upstream increased.Naturally occurring radioactive isotopes,especially on size-fractionated par-ticles,are therefore seen as useful tracers to understand the sources and behaviors of riverine particles transported from land to sea. 展开更多
关键词 the Yellow River suspended particulate matter size-fractions radionuclides sediment sources water elutriator
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Human Health Risks from Exposure to Heavy Metals of Suspended Particulate Matter around the Tongon Gold Mine, Côte d’Ivoire
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作者 Kagbagnan Kone Adjoumani Rodrigue Kouakou +4 位作者 Julien Bahino Horo Kone Kouakou Eric Adou Ehouman Ahissan Donatien Kopoin Adouby 《Journal of Agricultural Chemistry and Environment》 CAS 2023年第2期171-187,共17页
The Tongon mine, the largest gold mine in C?te d’Ivoire, has been in operation since April 2010. However, to our knowledge to date, no study has been conducted on metallic contamination in suspended particulate matte... The Tongon mine, the largest gold mine in C?te d’Ivoire, has been in operation since April 2010. However, to our knowledge to date, no study has been conducted on metallic contamination in suspended particulate matter (PM<sub>10</sub> and PM<sub>2.5</sub>) where there is a lack of information on the carcinogenic and non-carcinogenic risk to human health associated with the exposure of populations in the Tongon area to these pollutants. The general objective of this study is to evaluate the level of contamination of PM<sub>10</sub>;PM<sub>2.5</sub> by heavy metals and their impact on the health of populations exposed to these pollutants in the Tongon gold mine area. The sampling and measurement of suspended particulate matter (PM<sub>10</sub> and PM<sub>2.5</sub>) were done using a MiniVol TAS passive air sampler. Heavy metal concentrations were determined by inductively coupled plasma mass spectroscopy (Nex ION 2000 ICP-MS, USA). The results indicate that the average concentrations of suspended particles (PM<sub>2.5</sub> and PM<sub>10</sub>) obtained are all above the recommended exposure limits. In addition, among the heavy metals contained in the suspended particles, the concentrations of arsenic and nickel are high and all above the standard limit values. The assessment of the health risks related to the inhalation of PM<sub>10</sub> particles reveals that their inhalation over a long period could cause a carcinogenic risk. 展开更多
关键词 Particulate matters (PM10 and PM2.5) West Africa Tongon Heavy Metals INHALATION Carcinogenic Risk Metallic Contamination
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The Structure of Gravity Funnels and Stability Considerations of Matter in SI Units
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作者 Tobias Bartusch 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期71-81,共11页
This article describes an extension of the theory of vortices to electromagnetic types with a start point from known fluid systems. From this, properties of gravity-generating objects (particles and black holes) can b... This article describes an extension of the theory of vortices to electromagnetic types with a start point from known fluid systems. From this, properties of gravity-generating objects (particles and black holes) can be derived, which can also describe their possible interior. This also leads to questions about stability, which are then addressed and ultimately lead to considerations of black holes and their possible internal structure. The results fit into the observable areas and can also be directly verified because they were analytically calculated in SI units. 展开更多
关键词 Black Hole Dark matter Electromagnetic GRAVITY SINGULARITY VORTEX
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Differences in and factors controlling organic matter enrichment in the Ziliujing Formation shale in the Sichuan Basin
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作者 Peng Li Zhong-Bao Liu +4 位作者 He Bi Tao Jiang Rui-Kang Bian Peng-Wei Wang Xiao-Yu Shang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期77-86,共10页
Lacustrine shale oil and gas are important fields for unconventional exploration and development in China,and organic-rich shale deposition lays down the critical foundation for hydrocarbon generation.There are two se... Lacustrine shale oil and gas are important fields for unconventional exploration and development in China,and organic-rich shale deposition lays down the critical foundation for hydrocarbon generation.There are two sets of shale,the Dongyuemiao and Da’anzhai Members,in the Ziliujing Formation in the Sichuan Basin.To identify the differential enrichment characteristics of organic matter and clarify its controlling factors,geochemical analyses of organic and inorganic geochemical analyses were performed.The results showed that the total organic carbon content of the Dongyuemiao shale(1.36%)is slightly higher than that of the Da’anzhai shale(0.95%).The enrichment of organic matter in the two shales resulted from the comprehensive controls of paleoproductivity,paleoenvironment,and terrigenous input,but different factors have different effects.In addition,driven by climate,the change in the sulfate concentration in the bottom water further led to the different intensities of bacterial sulfate reduction in early diagenesis.This made a great difference regarding organic matter accumulation in the two members.In general,climate may have played a dominant role in organic matter enrichment in the two sets of shale. 展开更多
关键词 Lacustrine shale Ziliujing Formation Sichuan Basin Enrichment mechanism of organic matter
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New Approach to Synchronize General Relativity and Quantum Mechanics with Constant “K”-Resulting Dark Matter as a New Fundamental Force Particle
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作者 Siva Prasad Kodukula 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第1期292-302,共11页
Planck scale plays a vital role in describing fundamental forces. Space time describes strength of fundamental force. In this paper, Einstein’s general relativity equation has been described in terms of contraction a... Planck scale plays a vital role in describing fundamental forces. Space time describes strength of fundamental force. In this paper, Einstein’s general relativity equation has been described in terms of contraction and expansion forces of space time. According to this, the space time with Planck diameter is a flat space time. This is the only diameter of space time that can be used as signal transformation in special relativity. This space time diameter defines the fundamental force which belongs to that space time. In quantum mechanics, this space time diameter is only the quantum of space which belongs to that particular fundamental force. Einstein’s general relativity equation and Planck parameters of quantum mechanics have been written in terms of equations containing a constant “K”, thus found a new equation for transformation of general relativity space time in to quantum space time. In this process of synchronization, there is a possibility of a new fundamental force between electromagnetic and gravitational forces with Planck length as its space time diameter. It is proposed that dark matter is that fundamental force carrying particle. By grand unification equation with space-time diameter, we found a coupling constant as per standard model “α<sub>s</sub>” for that fundamental force is 1.08 × 10<sup>-23</sup>. Its energy calculated as 113 MeV. A group of experimental scientists reported the energy of dark matter particle as 17 MeV. Thorough review may advance science further. 展开更多
关键词 General Relativity Quantum Mechanics Space Time Dark matter A New Fundamental Constant “K”
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