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Impact of agricultural activities-motor vehicles and e-waste on sediment characteristics of the Serin River, Malaysia
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作者 LING Teck Yee Cornellia MUREK LEE Nyanti 《Journal of Environmental Science and Engineering》 2009年第9期13-22,共10页
Sediment is a sink for organic materials, nutrients and heavy metals and sediment condition affects the overlying water Though Serin River is a source of drinking water, agricultural and waste disposal activities in t... Sediment is a sink for organic materials, nutrients and heavy metals and sediment condition affects the overlying water Though Serin River is a source of drinking water, agricultural and waste disposal activities in the watershed may impact the sediment of the river. Therefore, the objective of this study was to investigate the organic matter, nutrients and heavy metals in the sediment of the Serin River. Five stations were selected for sediment sample collection. Results of the study show that organic matter (OM) ranged from 0.7% to 5.9%, TP was 100 -366 (mg/kg), TAN was 16-141 (mg/kg), TON was 550-3019(mg/kg), and TKN was 566-3160 (mg/kg). Sediment oxygen demand (SOD20) ranged from 5.6 to 14.2 (g O2/m^2/d). Among the five stations OM, TKN, and SOD of the sediment were second highest at the two stations downstream of animal (fish, chicken and pig) farming. TP and TAN were the second highest at the station downstream of fish farming and third highest at the station downstream of pig farming. Zn, Cu and Cd ranged from 132-357 (mg/kg), 26.7-96.7 (mg/kg) and 4.0-19.3(mg/kg). According to USEPA guideline, sediments at four stations were heavily polluted with Zn, Cu and Cd whereas the station that was farthest upstream, near a village, was slightly polluted with Zn and Cu. This study indicates that animal farming has an impact on the organic matter content, nutrients (N and P), oxygen demand and heavy metals of the sediment. Motor vehicles and discarded e-waste also contributed to the heavy metals in the sediment. Farm effluents and storm water should be treated and e-waste recycled to protect the water quality of the river for its designated use. 展开更多
关键词 sediment oxygen demand sediment characteristics heavy metals E-WASTE
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Investigation on the Sediment Characteristics of the Electrostatic Cyclonic Precipitator
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作者 李明华 马朝臣 +1 位作者 魏名山 吴千里 《Journal of Beijing Institute of Technology》 EI CAS 2006年第1期39-42,共4页
In order to find out the relationship between the sediment characteristics and collecting efficiency of the electrostatic cyclonic precipitator, an online study for the sediment characteristics of electrostatic cyclon... In order to find out the relationship between the sediment characteristics and collecting efficiency of the electrostatic cyclonic precipitator, an online study for the sediment characteristics of electrostatic cyclonic precipitator had been done with Kompton back scatter method, with the collecting efficiency tested at the same time. And the relationship between the sediment characteristics and the collecting efficiency was gotten. The sediment thickness increased with time extended and the concentration increased when the inlet velocity was fixed. The collecting efficiency increased with the inlet velocity increased, but dropped with the concentration increased. When the concentration and inlet velocity were fixed, the collecting efficiency drop a little with the increase of sediment thickness. The sediment would decrease the corona current in the collecting filed, which would make the electrostatic effect fall, then made the collecting efficiency drop a little. 展开更多
关键词 electrostatic cyclonic precipitator radial check sediment characteristic online
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Relationship between the characteristics of landforms and sediments as well as the plume front in the Hangzhou Bay
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作者 Feng Yingjun Li Yan and Li Bogen Second Institute of Oceanography, State Oceanic Administration, Hangzhou 310012, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1993年第1期133-144,共12页
Sedimentary environments in the Hangzhou Bay are introduced by a three-subregional landform pattern and a sedimentation map with six major sedimentation types. The geographic setting, sediment transportation and sedim... Sedimentary environments in the Hangzhou Bay are introduced by a three-subregional landform pattern and a sedimentation map with six major sedimentation types. The geographic setting, sediment transportation and sedimentation in different subregions are discussed with sediment grain parameters. Sedimentary basin suffering from effect of plume front can be identified by the fine sediments with median ( Mdφ ) 7φ-8φ, clay content 30% - 40% and silt 60% - 70%. Sediment transportation along the plume front seems not to be a direct effect on sedimentary formation of the shoals fringing the south coast of the Hangzhou Bay. 展开更多
关键词 Relationship between the characteristics of landforms and sediments as well as the plume front in the Hangzhou Bay well
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Characterization of the Songhua River sediments and evaluation of their adsorption behavior for nitrobenzene 被引量:15
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作者 Liu Ruiping Liu Huijuan +1 位作者 Wan Dongjin Yang Min 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第7期796-802,共7页
The explosion at a plant of the Jilin Petrochemical Corporation on 13 November,2005,and the spill of an estimated 100 t of toxic substances (nitrobenzene as the main component) into the Songhua River received worldwid... The explosion at a plant of the Jilin Petrochemical Corporation on 13 November,2005,and the spill of an estimated 100 t of toxic substances (nitrobenzene as the main component) into the Songhua River received worldwide attention.This study has focused on the adsorption behavior of nitrobenzene that spilled onto sediments along the Songhua River,which was one of the efforts to evaluate the fate of nitrobenzene after the spillage event.The organic carbon contents of these sediments along the Songhua River var... 展开更多
关键词 NITROBENZENE ADSORPTION sediment characteristics organic carbon content particle size distribution
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Sediment Movement in Periodic Alternating Current 被引量:11
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作者 CAOZude KONGLingshuang LIUDefu 《Journal of Ocean University of Qingdao》 2002年第2期201-205,共5页
The present paper summarizes the results of previous studies, including the structure and principle of the rotary ring flume for researching the fine sediment movement, the mechanism of the flume, method of eliminatin... The present paper summarizes the results of previous studies, including the structure and principle of the rotary ring flume for researching the fine sediment movement, the mechanism of the flume, method of eliminating the influence of the centrifugal force and sediment movement experiments with periodic alternating current. Also included are the experiment-based relationship among sediment concentration, bed shear stress and silt carrying capacity, a proposed erosion-deposition function and bed erosion-deposition calculation together with the results of verification. 展开更多
关键词 rotary ring flume periodic alternating current hydraulic characteristics of sediment erosion-deposition function
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Erosion and Sediment Production in Small Watershed in Purple Hilly Areas and Prevention Techniques 被引量:4
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作者 Zhang Bao-hua, He Yu-rong, Zhou Hong-yi, Zhu BoInstitute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, Sichuan, China Department of Geography, Liaocheng University, Liaocheng 252059, Shandong, China 《Wuhan University Journal of Natural Sciences》 CAS 2003年第03B期1041-1046,共6页
Purple Soil distributes extensively and mainly in China. Because of abundant easily weatherable parent rocks/ materials and unstable soil structure, and also influenced by parent materials, usage systems, and slope gr... Purple Soil distributes extensively and mainly in China. Because of abundant easily weatherable parent rocks/ materials and unstable soil structure, and also influenced by parent materials, usage systems, and slope gradients, erosion and sediment production of purple soils are very severe with main fashions of water erosion and gravitational erosion. Basing on observed data in small watersheds, rainfall erosivity, vegetation coverage, previous soil water content, flow and relating factors such as climate, topograph of small watershed, land usage, and soil kinds are all the influence factors of erosion and erodibility of purple soil as well as sediment production and transport in small watershed of purple hilly areas. The effective technological countermeasures of ecosystem restoration, agricultural tillage for water conservation and erosion prevention, agriculture project, and soil changing for fertility and anti-erosion were provided. 展开更多
关键词 purple soil characteristics of erosion and sediment production) influence factors prevention techniques
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Impacts of precipitation variation and soil and water conservation measures on runoff and sediment yield in the Loess Plateau Gully Region, China 被引量:8
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作者 XIA Lu SONG Xiao-yu +3 位作者 FU Na MENG Chun-fang LI Huai-you LI Yao-lin 《Journal of Mountain Science》 SCIE CSCD 2017年第10期2028-2041,共14页
The Loess Plateau of China has experienced a lengthy drought and severe soil erosion.Changes in precipitation and land use largely determine the dynamics of runoff and sediment yield in this region. Trend and mutation... The Loess Plateau of China has experienced a lengthy drought and severe soil erosion.Changes in precipitation and land use largely determine the dynamics of runoff and sediment yield in this region. Trend and mutation analyses were performed on hydrological data(1981–2012) from the Yanwachuan watershed in the Loess Plateau Gully Region to study the evolution characteristics of runoff and sediment yield. A time-series contrasting method also was used to evaluate the effects of precipitation and soil and water conservation(SWC) on runoff and sediment yield. Annual sediment yield declined markedly from 1981 to 2012 although there was no significant change in annual precipitation and annual runoff. Change points of annual runoff and annual sediment yield occurred in 1996 and 1997,respectively. Compared with that in the baseline period(1981–1996), annual runoff and annual sediment yield in the change period(1997–2012)decreased by 17.0% and 76.0%, respectively, but annual precipitation increased by 6.3%. Runoff decreased in the flood season and normal season, but increased in the dry season, while sediment yield significantly declined in the whole study period. The SWC measures contributed significantly to the reduction of annual runoff(137.9%) and annual sediment yield(135%) and were more important than precipitation. Biological measures(forestland and grassland) accounted for 61.04% of total runoff reduction, while engineering measures(terraces and dams) accounted for 102.84% of total sediment yield reduction. Furthermore, SWC measures had positive ecological effects. This study provides a scientific basis for soil erosion control on the Loess Plateau. 展开更多
关键词 Quantitative impact Trend analysis Evolution characteristics Runoff and sediment yield Rainfall Land use change
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Sedimentary Characteristics and Model of Gravity Flow Depositional System for the First Member of Upper Miocene Huangliu Formation in Dongfang Area, Yinggehai Basin, Northwestern South China Sea 被引量:10
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作者 Ming Sun Hua Wang +4 位作者 Jihua Liao Huajun Gan Jun Xiao Jinfeng Ren Shu'e Zhao 《Journal of Earth Science》 SCIE CAS CSCD 2014年第3期506-518,共13页
The gravity flow deposit were mainly developed in the lowstand systems tract(LST) of the first member of Upper Miocene Huangliu Formation(Ehl1) in Dongfang area, Yinggehai Basin, has become a valuable target for g... The gravity flow deposit were mainly developed in the lowstand systems tract(LST) of the first member of Upper Miocene Huangliu Formation(Ehl1) in Dongfang area, Yinggehai Basin, has become a valuable target for gas exploration and production. The gravity flow sedimentary characteristics of lithofacies associations, sedimentary texture, seismic facies and logging facies were described in detail on the basis of integrated analysis of cores, logging and seismic data. The sedimentary microfacies types composed of neritic sandbar, continental shelf mud, main channel, bifurcated or cross-cutting distributary channel, overspill, and natural levee are revealed under the constraint of high resolution sequence stratigraphic framework in the Ehl1. The gravity flow deposit system in the LST is divided into three evolution stages corresponding to periods of three parasequence sets. The gravity flow deposit was induced in the early LST, expanded rapidly in the middle LST and decreased slightly in the late LST. But its developing scale decreased sharply in the transgression systems tract(TST) and finally vanished in the highstand systems tract(HST). This spatial evolution rule is constrained by the integrated function of sediments supply of the Vietnam Blue River in the LST, the development of local gradient change in sea floor(micro-topography, i.e., flexure slope break), and the fall in relative sea level. On the basics of the deep study of the coupling relationship among the three main control factors, the sedimentary model is established as an optimal component of "source-channel-sink" for shallow marine turbidite submarine fan. 展开更多
关键词 Yinggehai Basin Dongfang area the first member of Upper Miocene Huangliu Formation(Ehl1) sedimentation characteristics gravity flow sedimentary model.
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Particle size distribution and characteristics of heavy metals in road-deposited sediments from Beijing Olympic Park 被引量:16
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作者 Haiyan Li Anbang Shi Xiaoran Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第6期228-237,共10页
Due to rapid urbanization and industrialization, heavy metals in road-deposited sediments(RDSs) of parks are emitted into the terrestrial, atmospheric, and water environment, and have a severe impact on residents' ... Due to rapid urbanization and industrialization, heavy metals in road-deposited sediments(RDSs) of parks are emitted into the terrestrial, atmospheric, and water environment, and have a severe impact on residents' and tourists' health. To identify the distribution and characteristic of heavy metals in RDS and to assess the road environmental quality in Chinese parks, samples were collected from Beijing Olympic Park in the present study. The results indicated that particles with small grain size(〈150 μm) were the dominant fraction. The length of dry period was one of the main factors affecting the particle size distribution, as indicated by the variation of size fraction with the increase of dry days. The amount of heavy metal(i.e., Cu, Zn, Pb and Cd) content was the largest in particles with small size(〈150 μm) among all samples. Specifically, the percentage of Cu, Zn, Pb and Cd in these particles was 74.7%, 55.5%, 56.6% and 71.3%, respectively.Heavy metals adsorbed in sediments may mainly be contributed by road traffic emissions. The contamination levels of Pb and Cd were higher than Cu and Zn on the basis of the mean heavy metal contents. Specifically, the geoaccumulation index(I geo) decreased in the order:Cd〉Pb〉Cu〉Zn. This study analyzed the mobility of heavy metals in sediments using partial sequential extraction with the Tessier procedure. The results revealed that the apparent mobility and potential metal bioavailability of heavy metals in the sediments, based on the exchangeable and carbonate fractions, decreased in the order: Cd〉Zn≈Pb〉Cu. 展开更多
关键词 Size distribution characteristics Heavy metals Road-deposited sediments Contamination assessment Beijing Olympic Park
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THE SEISMIC PROFILER FOR DEEP SEDIMENT LAYERS AND ITS CHARACTERISTICS
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《Chinese Journal of Acoustics》 1989年第3期219-226,共8页
DDCl-1 type seismic profiler for deep sediment layers is a large scale marine survey equipment. Its penetrating strata depth may reach to 1 km. This equipment suits surveys for continental shelf,seafloor trench and ge... DDCl-1 type seismic profiler for deep sediment layers is a large scale marine survey equipment. Its penetrating strata depth may reach to 1 km. This equipment suits surveys for continental shelf,seafloor trench and geological structure under seafloor etc. It suits also geological environment surveys of seafloor resources.The working principle, block diagrams composition and echo signal processing characteristics are presented, and some typical strata profiles are shown. 展开更多
关键词 THE SEISMIC PROFILER FOR DEEP sediment LAYERS AND ITS characteristics ITS
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Insights on pretreatment of Indian hematite fines in grate-kiln pelletizing process: the choice of grinding processes 被引量:3
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作者 De-qing Zhu Zheng-qi Guo +1 位作者 Jian Pan Zhao-yuan Wang 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2018年第5期506-514,共9页
Indian hematite fines are normally characterized by high iron grade and minor impurities, which are usually used for sinter fines. With macroscale operations technology of blast furnace in Indian, pellets, as a kind o... Indian hematite fines are normally characterized by high iron grade and minor impurities, which are usually used for sinter fines. With macroscale operations technology of blast furnace in Indian, pellets, as a kind of high-quality materials, attract more and more attention. However, the hematite fines possess the coarse size. Hence, they inevitably need to be further finely ground for pelletizing before balling. The grinding behavior of Indian hematite fines was revealed by conducting the ball milling tests and determining the Bond ball mill work index (Wi). The results show that Indian hematite fines have an excellent grindability with Wi of only 7.40-7.73 kWh/t, indicating that ball milling is an economically viable way to pretreat Indian hematite fines. Nonetheless, due to poor sedimentation and filtering properties of wet ground products, the dry ball milling is more appropriate to process Indian hematite fines. In addition, the superior quality green balls can be manufactured with dry ground products under the conditions of 0.5% bentonite dosage, 7.5% moisture and balling for 12 min, which further confirmed that the recommended pellet feed preparation technique is reasonable. 展开更多
关键词 Indian hematite fine · Dry ball milling · Wet ball milling · Bond work index · sedimentation characteristic ·Filtration characteristic
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